cssi/SciSciGPT-SciSciNet huggingface dataset:
STATISTICAL METHODOLOGY : VI. MATHEMATICAL MODELING OF THE ELECTROCARDIOGRAM USING FACTOR ANALYSIS

The ECG is a 12-lead-vector system and is known to contain redundant information. Factor analysis (FA) is a statistical technique that improves measured data and eliminates redundancy by identifying a minimum number of factors accounting for variance in the data set. Objective To identify the minimum number of lead-vectors required to predict the 12-lead ECG. Methods A total of 104 ECGs were obtained from 24 normal men, 22 normal women, and 28 men and 30 women with variable pathologies. Each ECG lead was simultaneously acquired and digitized, resulting in a voltage-time data array stored for mathematical analysis. Each array was factor-analyzed to identify the minimum number of lead-vectors spanning the ECG data space. The 12-lead ECG was then predicted from this minimum lead-vector set. ANOVA was used to test for statistical significance between normal and pathologic data groups. Results FA revealed that 3 lead-vectors accounted for 99.12%+/-0.92% (95% CI+/-0.18%) of the variance contained in the 12-lead ECG voltage-time data for all 104 cases. There were no statistically significant differences between men and women (99.25%+/-0.66% vs 98.98+/-1.11%; p=0.139). Statistically significant differences were noted between normal and acute myocardial infarction ECGs (99.5%+/-0.27% vs 98.66+/-1.25%; p=0.00003). The measured and predicted leads were almost identical. A 3-dimensional spatial ECG derived from the 3-lead-vector set resulted in variable curved surfaces that differed by pathology. Conclusions The 12-lead ECG can be derived from only 3 measured leads and graphed as a 3-D spatial ECG. This type of data processing may lead to instantaneous acquisition and may enhance the diagnostic capability of the ECG from routine bedside telemetry equipment.
Guest Editorial for the Special Issue on Large and Multiscale Computational Electromagnetics

The 28 papers in this special issue focus on large and multiscale computational electromagnetics. The issue starts with five papers on the finite-difference time-domain (FDTD) method, then proceeds with five on the finite-element method (FEM) and eighteen on integral equation (IE) solvers. The papers are briefly summarized here.
Reduction of symptoms in binocular anomalies using computerized home therapy-HTS.

Abstract Background Asthenopic symptoms often are associated with various accommodative/vergence disorders. Recent studies have found that symptoms associated with convergence insufficiency are reduced by in-office vision therapy with supplemental home therapy. No studies have used standardized symptom questionnaires to evaluate the effectiveness of either in-office or home-based vision therapy in binocular anomalies other than convergence insufficiency. This retrospective study was designed to evaluate the changes in symptoms using an automated, home computer vision therapy program (HTS™) in accommodative/vergence disorders. Methods A retrospective study of 43 prepresbyopic patients who completed the HTS was performed. Before and immediately after treatment all patients in this study completed a 15-question symptom questionnaire (Convergence Insufficiency Symptom Survey). Treatment consisted of various accommodative and vergence activities. Results Initial symptoms scores on the scaled questionnaire were 32.8 (SD = 8.1); after therapy they were 20.6 (SD = 11.5). These changes were both clinically and statistically significant. Forty percent were “normalized” and 55% improved. Convergence amplitude improved from 22Δ to 53Δ after treatment, and divergence amplitudes improved from 15Δ to 25Δ. These findings were clinically significant. Lastly, more than 75% of the patients finished the program by 40 sessions (equivalent to 8 weeks). Conclusion Automated vision therapy delivered by the HTS system improved convergence and divergence amplitudes with a concomitant reduction in symptoms. The HTS system should be used on those patients with symptoms associated with an accommodative/vergence anomaly when in-office vision therapy supplemented with home therapy is not practical.
Purification of the resin amberlite IR-100 for blood coagulation studies.

Summary1. A method of purification of resin Amberlite IR-lOO was devised. When blood was treated with the purified resin a decreased sedimentation rate was found, with morphological, chemical, and physical properties otherwise practically unmodified.2. Of the factors involved in blood coagulation, prothrombin, fibrinogen and the labile factor described by Quick apparently were not appreciably altered by the decalcification with Amberlite, With optimal recalcification, the clotting time of the treated blood was much shorter than that of native blood, but this is also true for oxalated and citrated blood.3. A reduced antithrombin activity was observed in Amberlite plasma upon incubation with “full strength” thrombin. Since citrated plasma responded similarly, the be- of decalcification of the 3 agents. haviour may be linked with the mechanism
Correlation based swarm trackers for 3-dimensional manifold mesh formation

Our group has developed several methods for acquiring 3-dimensional objects in motion which include facial expressions. For this to be practical we need to identify and track various features contained in facial expressions. To accomplish this we introduce a set of feature based trackers and propose strategies for combining them together to form meshes. We present our strategy in the context of swarm theory where the elements of the swarm are the feature trackers and the communication structure of the swarm is essentially a spatial mesh. We demonstrate the concepts with examples of facial feature tracking.
A dispensable Plasmodium locus for stable transgene expression

Abstract The ribosomal small subunit locus has been used for transgene expression in the rodent malaria parasites, Plasmodium berghei and Plasmodium yoelii , but this strategy utilizes single crossover integration and is thus prone to reversion by plasmid excision. Targeting of the ribosomal subunit locus may also have a negative effect on oocyst development in the mosquito. In P. berghei , the p230 paralog locus has been used for transgene expression. Here, we show that the P. yoelii S1 locus (sporozoite expressed gene 1) (PY05712) is dispensable and can be used for stable transgene expression throughout the parasite life cycle. P. yoelii s1 − parasites show no defect in blood stage replication, oocyst formation, sporozoite production, or liver stage development when compared to P. yoelii wildtype parasites. Further, we show that a fluorescent transgene can be stably expressed from this site. This demonstrates that the S1 locus can be utilized for stable expression of heterologous genes in rodent malaria parasites.
Repression of mutagenesis by Rad51D-mediated homologous recombination

Homologous recombinational repair (HRR) restores chromatid breaks arising during DNA replication and prevents chromosomal rearrangements that can occur from the misrepair of such breaks. In vertebrates, five Rad51 paralogs are identified that contribute in a nonessential but critical manner to HRR efficiency. We constructed and characterized a Rad51D knockout cell line in widely studied CHO cells. The rad51d mutant (51D1) displays sensitivity to a wide spectrum of induced DNA damage, indicating the broad relevance of HRR to genotoxicity. Untreated 51D1 cells exhibit {approx}5-fold elevated chromosomal breaks, a 12-fold increased rate of hprt mutation, and 4- to 10-fold increased rates of gene amplification at the dhfr and CAD loci, respectively. These results explicitly show the quantitative importance of HHR in preventing these types genetic alterations, which are associated with carcinogenesis. Thus, HRR copes in an error-free manner with spontaneous DNA damage encountered during DNA replication, and Rad51D is essential for this fidelity.
High-speed n-i-p-i Photodetector with internal gain

A new type of infrared detector made from n-i-p-i doping superlattice crystals with laterally graded doping is proposed. Photogenerated electrons are rapidly and efficiently swept by a built-in drift field into a small area for detection with high pholoconductive gain. The operation at voltages much below 1 volt implies very low noise. Inspite of the low voltage the capacitance is also much smaller than in conventional p-i-n detectors. The sensitivity of optical receivers using this detector may become photon-noise limited in the low Gbit/s range. Practical advantages of the device include modest requirements on crystal purity and on control of doping level and its suitability for monolithic integration.
Use of medical students in a flipped classroom programme in nutrition education for fourth-grade school students:

Objective:The purpose of this study was to evaluate the feasibility of a flipped classroom progamme, designed and implemented by medical students, in communicating nutrition education to fourth-gra...
Reflection-based imaging of macular pigment distributions in infants and children

We have developed a reflection-based capability of the RetCam® platform, an FDA-cleared pediatric retinal-imaging instrument, for the purpose of measuring macular pigment levels as well as their spatial distributions in infants and children. Our modifications include narrow-band blue-wavelength excitation of the macular pigment absorption in combination with spectrally selective blue-wavelength readout of the reflection signals received by the instrument’s CCD detector array. Furthermore, an algorithm is developed that allows the computation of optical density maps for the macular pigment relative to peripheral retinal areas. This made it possible for the first time to directly measure macular pigment levels and their spatial features in the developing human retina. In contrast to adults, infants with measurable pigment levels had almost exclusively a narrow, circularly symmetric, pigment distribution. The described methodology holds promise for future investigations into the role of macular pigment in the developing human retina and the effect of dietary interventions in diseases resulting from a lack of normal carotenoid levels.
My Approach to the Treatment of Scleroderma

Systemic sclerosis (scleroderma) is unique among the rheumatic diseases because it presents the challenge of managing a chronic multisystem autoimmune disease with a widespread obliterative vasculopathy of small arteries that is associated with varying degrees of tissue fibrosis. The hallmark of scleroderma is clinical heterogeneity with subsets that vary in the degree of disease expression, organ involvement, and ultimate prognosis. Thus, the term scleroderma is used to describe patients who have common manifestations that link them together, whereas a highly variable clinical course exists that spans from mild and subtle findings to aggressive, life-threatening multisystem disease. The physician needs to carefully characterize each patient to understand the specific manifestations and level of disease activity to decide appropriate treatment. This is particularly important in treating a patient with scleroderma because there is no treatment that has been proven to modify the overall disease course, although therapy that targets specific organ involvement early before irreversible damage occurs improves both quality of life and survival. This review describes our approach as defined by evidence, expert opinion, and our experience treating patients. Scleroderma is a multisystem disease with variable expression; thus, any treatment plan must be holistic, yet at the same time focus on the dominant organ disease. The goal of therapy is to improve quality of life by minimizing specific organ involvement and subsequent life-threatening disease. At the same time the many factors that alter daily function need to be addressed, including nutrition, pain, deconditioning, musculoskeletal disuse, comorbid conditions, and the emotional aspects of the disease, such as fear, depression, and the social withdrawal caused by disfigurement.
Do pessaries prevent the progression of pelvic organ prolapse

Pessaries are used for the management of pelvic organ prolapse, but it is unknown whether a pessary will prevent progression of this condition. The purpose of this study was to describe the course of pelvic organ prolapse among women using a pessary for at least 1 year. Among 56 consecutive women fitted with a pessary, 19 (33.9%) continued its use under our care for at least 1 year. We compared baseline and follow-up examinations, using the Pelvic Organ Prolapse Quantitation examination system. At baseline, 16 (84.2%) had stage 3 or 4 prolapse. After 1 year we observed a significant improvement in the stage of disease (P = 0.045, Wilcoxon signed rank test). Four women (21.1%, 95% confidence interval −0.2, 43.7%) had an improvement in stage. No women had worsening in stage of prolapse. These data suggest that there may be a therapeutic effect associated with the use of a supportive pessary.
Critical review of SPECT imaging in pulmonary embolism

Outcome studies have shown that pulmonary embolism can be safely excluded in patients with negative ventilation/perfusion (V/Q) single-photon emission computed tomography (SPECT). The effective radiation dose of V/Q SPECT is much less than with computed tomographic (CT) pulmonary angiography, which would make it preferable to CT angiography in many young female patients. The accuracy of V/Q SPECT, however, is difficult to assess, because most published investigations are limited by incorporation bias or partial verification bias, as well as other limitations in study design and reporting. Consequently, the accuracy of V/Q SPECT relative to planar V/Q scintigraphy or CT angiography has not been definitively determined. There is need for a prospective investigation of the accuracy of V/Q SPECT with consecutive patients, blinded interpretations, and an independent reference standard, or independent composite reference standard.
Further evaluation and development of charge similarity indices for choosing molecular analogues

Two molecular charge similarity index (CSI) methods are further evaluated for practical application: one method based on a simple CNDO-type approximation to the electron density function and the other based on an ab initio pseudo total charge density function. The test system consists of isosteric analogues of dimethyl ether and methoxy acetic acid. The effects of differences in skeletal structure on the CSI measure of electron density similarity about corresponding atoms is estimated, and two new developments are presented for application of the ab initio-based method: (1) an INDO-type approximation which improves the efficiency of the CSI calculation; and (2) a FOCUS feature which enables comparisons of local molecule regions.
Can shape be perceived by dynamic touch

The possibility that some aspects of the shapes of solid objects can be perceived through dynamic touch, even when the objects are not touched, but simply wielded with a handle, was investigated in four experiments. Wooden solids were constructed of three sizes and five shapes: hemisphere, cylinder, parallelepiped, cone, and pyramid. Experiments 1 and 2 involved comparisons (judgments of same or different) between and among wielded objects of the same mass. In Experiments 3 and 4, subjects were required to wield an object and to select a match from a visible arrangement of objects of the five shapes; the wielded objects were of two sizes, each different from that of the visible objects. The success of subjects at these tasks, and the patternings of errors, are seen to involve the characteristic moment of inertia profiles of each shape, and a ratio of the object’s resistances to rotation around orthogonal axes is shown to be a strong predictor of performance in the identification experiments. The results are discussed with reference to dynamic touch and to the notion of shape invariants that do not reduce to aspects of object surface.
Mechanisms of Photochemical Reactions in Solution. LXXIV. The Photochemistry of 3‐Methyl‐1‐Phenoxybut‐2‐Ene.,

The photochemical reactions of 3-methyl-1-phenoxybut-2-ene (γ,γ-dimethylallyl phenyl ether), I, were investigated in solution and in the gas phase. Irradiation of I resulted in the formation of phenol, II, 3-methyl-3-phenoxybutene, III, 1-(2-hydroxyphenyl)-3-methylbut-2-ene, IV, 1-(4-hydroxyphenyl)-3-methylbut-2-ene, V, 3-(2-hydroxyphenyl)-3-methylbutene, VI, and 3-(4-hydroxyphenyl)-3-methylbutene, VII. Formation of III - VII in the gas phase was efficiently quenched by nitric oxide. The results suggest that all products were formed by a dissociation - radical recombination mechanism and that none were formed by concerted processes. The absorption spectrum of I and its quantum yields for fluorescence and photochemical reaction were used to estimate the rates of the processes which deactivate its lowest-lying excited singlet state. The results suggest that OC bond homolysis need not occur via intersystem crossing from an S1 (π, π*) to a 3σ (CO) state. Fragmentation to radicals, and perhaps rapid non-radiative decay without chemical reaction, probably involve internal conversion with population of high vibrational levels of the CO bond. Weak electronic interaction between the aromatic nucleus and the olefinic chromophore may also be important.
Association and linkage analysis of candidate genes GRP, GRPR, CRHR1, and TACR1 in panic disorder†

Panic disorder (PD) is a debilitating anxiety disorder, characterized by recurrent episodes of intense fear that are accompanied by autonomic and psychological symptoms leading to behavioral impairment. Basic research implicates neuropeptide-signaling genes in the modulation of anxiety and stress. The genes encoding corticotropin releasing hormone receptor 1 (CRHR1), tachykinin receptor 1 (TACR1), gastrin releasing peptide (GRP), and gastrin releasing peptide receptor (GRPR) were selected as candidates for PD based on their biology. Linkage and association analysis in 120 multiplex U.S. PD pedigrees was performed using 21 single nucleotide polymorphisms (SNPs). Parametric and non-parametric linkage tests in pedigrees, for single point and multipoint analysis, revealed limited support for genetic linkage to TACR1 (parametric and non-parametric lod scores ∼1). The family-based association test (FBAT) generated nominal support for allelic association in TACR1 (P = 0.02), and GRP (P = 0.02), findings which must be considered in the light of multiple comparisons. Further exploration of the GRP and TACR1 findings in large case-control PD samples may provide more definitive evidence implicating these loci in the genetic etiology of PD. © 2008 Wiley-Liss, Inc.
Racial and ethnic differences in patients' preferences for initial care by specialists ☆

Abstract Purpose To examine racial and ethnic differences in patients' preferences for initial care by specialists, and to determine whether trust in the physician and health beliefs account for these differences. Methods We conducted a cross-sectional study of 646 patients in the waiting room of three academic-based internal medicine outpatient practices. We asked subjects about their preference to see their primary care provider or a specialist first regarding the actual health problem that had brought them to see their physician as well as regarding three hypothetical scenarios (2 weeks of new-onset exertional chest pain, 2 months of knee pain, and rash for 4 weeks). We examined the relation among patients' preference for initial care by a specialist and their demographic characteristics, global ratings of their primary care physician and health plan, trust in their primary care physician, and other health beliefs and attitudes. Results Averaged for the three scenarios and actual health problem, 13% of patients preferred to see a specialist first. Adjusting for all other covariates, blacks (risk ratio [RR] = 0.55; 95% confidence interval [CI]: 0.20 to 0.92) and Asians (RR = 0.46; 95% CI: 0.19 to 0.75) were much less likely to prefer a specialist than were whites. Patients with less confidence in their primary care physician and greater certainty about needed tests and treatments were more likely to prefer a specialist. These variables, however, did not explain the difference in preference for specialist care among blacks, Asians, and whites. Conclusion Blacks and Asians are less likely than whites to prefer initial care by a specialist. Future studies should examine whether differences in preference for care lead minorities to underutilize appropriate specialty care or lead whites to overuse specialty care.
Photosynthetic Electron Transport in Spheroplasts and Thylakoid Membranes from the Thermophilic Blue-Green Alga, Synechococcus lividus.

Summary Photosynthetic electron transport measurements and related analyses were carried out on spheroplasts and membrane fragments from the thermophilic blue-green alga, Synechococcus lividus . Intact spheroplasts that contained all of their phycobilin content required the presence of a lipophilic electron transport acceptor in the reaction medium for electron transport to proceed through Photosystem II. After gentle hypotonic shock, the resulting membrane fragments exhibited photosynthetic control through Photosystem II, with maximum electron transport activity occurring at 45 °C. Photosystem II electron transport was inhibited by DCMU. Analysis of membrane-bound cytochromes indicated the presence of the low potential cytochrome c549 , in addition to high and low potential cytochrome bs59, cytochrome f, and cytochrome b563. Membrane fragments exhibited cyclic photophosphorylation around Photosystem I and very slow rates of phosphorylation through Photosystem II. These results suggest that this organism is a promising system for the study of photosynthetic electron transport in cyano- phytes.
Effects of Enantiomeric Blend of Verbenone on Response ofIps paraconfusus to Naturally Produced Aggregation Pheromone in the Laboratory

The aggregation pheromone produced by maleIps paraconfusus (Coleoptera: Scolytidae) tunneling in Monterey pine,Pinus radiata, logs was trapped on Porapak Q. A concentration of an extract of trapped volatiles that attracted beetles was determined in the laboratory through a concentration–response analysis of walking behavior of males and females. The interruptant effects of four concentrations of verbenone on response to a constant concentration of this naturally produced aggregation pheromone were tested with males and females. Independent of its enantiomeric composition [99.5% (S)-(−), 93.1 % (S)-(−), and 98.3% (R)-(+)], verbenone significantly reduced the percentage of females (but not males) reaching the attractant source. However, when the time required for beetles of both sexes taken together to reach the attractant source was considered, verbenone of higher enantiomeric purity had a greater effect on beetle behavior. Solutions of 99.5% (S)-(−)- and 98.3% (R)-(+)-verbenone increased the time required for beetles to reach the attractive source when compared to 93.1% (S)-(−)-verbenone. When pooled across enantiomeric blends, increasing concentrations of verbenone resulted in slower responses in beetles that reached the attractant source within 2 min. Males and females did not respond to verbenone alone.
Effects of sildenafil citrate (Viagra) on choroidal congestion.

This study evaluates the effect of sildenafil on choroidal vascular congestion and its correlation with visual effects. Thirteen healthy subjects were randomized to a sildenafil group (n = 7, 3 M, 4 F), who received 200 mg of sildenafil, and a control (n = 6, 5 F, 1 M) group, who received no drug. Measurements of choroidal thickness with ultrasonography, color vision with Desaturated Panel D-15 Test, and contrast sensitivity with CSV-1000e charts (Vector Vision) were performed at baseline and at 90 and 180 min. Mean choroidal thickness and contrast sensitivity did not change significantly relative to baseline in either group. However, the variance in differences between repeat and baseline measurements of choroidal thickness was significantly higher at 90 min (p = 0.003) in the sildenafil subjects. Color discrimination error scores increased after sildenafil but did not correlate with changes in choroidal thickness. An oral dose of 200 mg of sildenafil caused small inconsistent changes in choroidal thickness, which did not correlate with visual effects.
A flash photolysis study of the photo-oxidation of acetaldehyde at room temperature

Abstract Acetaldehyde was flash photolyzed in the presence or air of O2 at 25°C. The transient absorption spectrum of CH3O2 was monitored and quantum yields were obtained with 310.5, 302.0 and 294.0 nm incident radiation. The CH3O2 signal reached full intensity in less than 7 μs, the time resolution of our equipment, at 310.5 nm for a mixture of CH3CHO at 25.0 Torr and O2 at 20.0 Torr. The quantum yields decreased with increasing air pressure, the half-quenching pressures being 187 ± 28 Torr, 578 ± 109 Torr and 941 ± 237 Torr respectively for 310.5 nm, 302.0 nm and 294.0 nm incident radiation. These quenching results are in good agreement with values in the literature.
A synthetic and MO-SCF study of the trifluoroethoxylation of trifluoromethylchloropyridine derivatives

Abstract The trifluoroethoxylation of a series of trifluoromethylchloropyridines was studied. The reactivity, selectivity and leaving ability of the chloro- and trifluoromethyl- group were discussed. The influence of different substituents on the reactivity of the pyridine ring was also studied using the molecular orbital method.
A Class of Multivariate Distributions

Summary In this paper we introduce a class of multivariate distributions, known as the generalized Liouville distribution and defined by the functional form (0 ≤xi 0, βi > 0, qi > 0). It is shown that such distributions can be used to derive both the Dirichlet distribution and the beta distribution of the second kind.
Environment, health & safety management systems for upstream oil & gas projects in developing countries

The international oil and gas exploration and production industry faces a vast array of environmental issues that are global in nature but play an increasingly prominent role in individual project decision making. When placed against a backdrop of socio-political and cultural challenges presented in developing countries, project planners require an enlightened approach to ensure the environmental, economic and social components are appropriately balanced to ensure sustainable business success. Although a relatively new player in the international E & P industry, Canadian Occidental Petroleum Ltd. has developed such an approach to EMS management for projects in developing countries. Drawing from recent experience with a major project in Yemen, and others in the planning stages in several other developing countries, this paper presents a number of positive strategies and actions which are being applied in the many countries in which the company is active. Lessons learned and opportunities for improvement are presented for consideration by responsible operators working internationally toward the goal of environmentally sustainable energy development.
Role of Iron in Human Serum Resistance of the Clinical and Environmental Vibrio vulnificus Genotypes

We recently reported a simple PCR procedure that targets a sequence variation of the virulence-correlated gene locus vcg. It was found that 90% of all clinical isolates possessed the vcgC sequence variant, while 93% of all environmental isolates possessed the vcgE sequence variant. Here we report that the clinical genotype of Vibrio vulnificus is significantly better able to survive in human serum than is the environmental genotype. The presence of a siderophore-encoding gene, viuB, influenced serum survivability among all isolates of V. vulnificus tested. Those strains positive for viuB (all C-type strains but very few E-type strains) showed greater serum survivability than those lacking viuB (most E-type strains). The addition of iron (in the form of ferric ammonium citrate) to human serum restored the survival of E-type strains lacking viuB to levels not significantly different from those of C-type and E-type strains that possess viuB. These findings suggest that viuB may dictate serum survival in both C- and E-type strains of V. vulnificus and may explain why some strains (C- and E-type strains) are pathogenic and others (predominately E-type strains) are not. Additionally, C-type strains exhibited a cross-protective response against human serum, not exhibited by E-type strains, after incubation under nutrient and osmotic downshift conditions that mimicked estuarine waters. This suggests that the nutrient/osmotic environment may influence the survival of V. vulnificus following entry into the human body, leading to selection of the C genotype over the E genotype.
Bandgap voltage reference sources in CMOS technology

Two configurations are proposed for the implementation of bandgap reference sources in CMOS technology. The circuits presented are capable of high temperature operation, and allow a choice of the positive supply rail, the negative supply rail, or ground as the reference point.
A method for measuring mean wind velocities in a canyon with tracer balloons

A method using balloons as tracers for measuring mean wind velocity in street canyons or mountain valleys has been developed. Tests of the method with numerical experiments showed that the method reproduced an assumed wind field quite well provided that the buoyancy component of the balloon velocity was larger than the downward velocity component of the wind. Tests of the method with measurements of wind velocity in a street canyon of downtown Chicago showed that the method yielded flow patterns quite similar to photographic results of flow visualization of phisical simulations by other investigators. However, no direct measurements of wind velocity were available for quantitative comparison.
Citrus Canker: The Pathogen and Its Impact

The U.S. has seen an increase in introductions of invasive plant pests into agricultural crops. In Florida, one such invasive species is a bacterial plant pathogen that causes Asiatic citrus canker...
Identification and Characterization of Novel Small-Molecule Protease-Activated Receptor 2 Agonists

We report the first small-molecule protease-activated receptor (PAR) 2 agonists, AC-55541 [ N -[[1-(3-bromo-phenyl)-eth-( E )-ylidene-hydrazinocarbonyl]-(4-oxo-3,4-dihydro-phthalazin-1-yl)-methyl]-benzamide] and AC-264613 [2-oxo-4-phenylpyrrolidine-3-carboxylic acid [1-(3-bromo-phenyl)-( E / Z )-ethylidene]-hydrazide], each representing a distinct chemical series. AC-55541 and AC-264613 each activated PAR2 signaling in cellular proliferation assays, phosphatidylinositol hydrolysis assays, and Ca 2+ mobilization assays, with potencies ranging from 200 to 1000 nM for AC-55541 and 30 to 100 nM for AC-264613. In comparison, the PAR2-activating peptide 2-furoyl-LIGRLO-NH 2 had similar potency, whereas SLIGRL-NH 2 was 30 to 300 times less potent. Neither AC-55541 nor AC-264613 had activity at any of the other PAR receptor subtypes, nor did they have any significant affinity for over 30 other molecular targets involved in nociception. Visualization of EYFP-tagged PAR2 receptors showed that each compound stimulated internalization of PAR2 receptors. AC-55541 and AC-264613 were well absorbed when administered intraperitoneally to rats, each reaching micromolar peak plasma concentrations. AC-55541 and AC-264613 were each stable to metabolism by liver microsomes and maintained sustained exposure in rats, with elimination half-lives of 6.1 and 2.5 h, respectively. Intrapaw administration of AC-55541 or AC-264613 elicited robust and persistent thermal hyperalgesia and edema. Coadministration of either a tachykinin 1 (neurokinin 1) receptor antagonist or a transient receptor potential vanilloid (TRPV) 1 antagonist completely blocked these effects. Systemic administration of either AC-55541 or AC-264613 produced a similar degree of hyperalgesia as was observed when the compounds were administered locally. These compounds represent novel small-molecule PAR2 agonists that will be useful in probing the physiological functions of PAR2 receptors.
Electrohydraulic shock wave decalcification of stenotic aortic valves: postmortem and intraoperative studies.

Abstract Decalcification of stenotic aortic valves is limited by the difficulty in removing sufficient calcium to restore valve function without cusp perforation. The present study demonstrates that electrohydraulic shock waves generated by a hand-held lithotriptor fragmented the calcifications contained within the cusps of four necropsy specimens of stenotic aortic valves. The electrohydraulic shock waves appeared to create a cleavage plane between the valve tissue and the fragmented calcific deposits, allowing the fragmented calcined masses to be removed without cusp perforation. Five patients with severe aortic stenosis also underwent successful aortic valve decalcification augmented by electrohydraulic shock waves generated with the hand-held lithotriptor, without significant complication. The shock waves permitted removal, from the aortic valve, of calcium that had not been removed by mechanical means. These results indicate that the addition of electrohydraulic shock waves to mechanical aortic valve decalcification may facilitate successful decalcification in patients undergoing operative treatment for aortic stenosis and may allow patients to avoid the need for aortic valve replacement.
STABILITY OF PHYTOLACCANIN, BETANIN AND FD&C RED #2 IN DESSERT GELS

Color stability of phytolaccanin (from Phytolucca americana), betanin (from Beta vulgaris) and FD&C Red #2 was studied in pectin and gelatin gels at -28, 4.4, 21 and 38°C. Phytolaccanin and beta-nin, which are identical chemically, were purified by a solvent extraction process. Both are feasible as colorants for soft (pectin) gels and firm (gelatin) gels but are not as stable as Red #2. Both are slightly more stable in gelatin gels containing pectin, or added citric acid, or ascorbic/citric acid mixtures, at temperatures of 21°C or lower. All three pigments in gelatin gels with added ascorbic/citric acid were unstable at 38°C.
Special issue on information retrieval for program comprehension

Welcome to the special issue on information retrieval for program comprehension (IR4PC). IR4PC employs various interdisciplinary information search techniques to examine the properties of both existing (legacy) and newly created software. IR4PC is important for software reuse, software maintenance and evolution, and reverse engineering, just to mention a few areas. Back in the 1980s and early 1990s, much program comprehension involved representing program code as control and data flow graphs. Recognizing program constructs was performed by comparing flow graphs to a plan library of known constructs (e.g. Rich and Waters 1989). However, formal non-heuristic approaches to program comprehension have been shown to be NP-hard and their success was often illustrated only in toy domains (Woods and Yang 1996). For this reason, heuristic approaches acquired new importance. In the 21st century, much program comprehension research has focused on applying various information retrieval techniques (e.g. text mining, LSI, knowledge-based NL understanding) to software. These new IR4PC semantic measures examine informal information in the tokens within the software itself (e.g. identifier names, function names and variable names, code comments) as well as the natural language content in external documentation such as software requirements documents or software design documents. In the past, IR4PC techniques have been successfully applied to (among other areas) static concept location (using information derived from informal tokens together with structural information such as call graphs to locate code sections that are related to given concepts), to determining whether a particular software component is reusable, to dynamic search or software reconnaissance (examining informal tokens along execution traces of program executed with and without a particular feature), to developer identification (determining which developer is the best one to perform a particular task), to bug location Empir Software Eng DOI 10.1007/s10664-008-9097-1
Indexing techniques for historical databases

Two indexing structures based on R-trees are proposed for historical data, which can span magnetic disk and optical disk media. The performance of these indexes is compared to that of two other indexing candidates that are each contained entirely on one medium. Test results indicate that the proposed indexes perform well when compared to an index that is contained entirely on optical disk. >
Molecular Dynamics Simulation of the Glass Transition of Ortho-Terphenyl in Bulk and Thin Films

The glass transition temperature in thin film depends strongly on film thickness and interaction with the substrate and it is normally a priori not clear which way it deviates from the bulk value. This causes new challenge in the technological advancement of smaller and smaller electronic devices. In this study molecular dynamics simulations of a low-molecular weight organic glass former, ortho-terphenyl (OTP), are carried out in bulk and freestanding films. The main motivation is to provide insight into the confinement effect without interface interactions. Based on earlier models of ortho-terphenyl we developed an atomistic model for bulk simulations. The model reproduces the literature data from simulations as well as experiments. After characterizing the bulk model using 800 OTP molecules, we form a freestanding film. This film gives us the opportunity to study the dynamical heterogeneity near the glass transition by inplane mobility and reorientation dynamics. We also develop a structurally coarse-grained model for this glass former based on our atomistic model to study bigger systems for longer times in the future. At present we are using 800 molecules for the mesoscale system as well.
The effect of a poverty reduction policy and service quality standards on commune-level primary health care utilization in Thai Nguyen Province, Vietnam

Although universal access to quality health services is a primary policy goal of the Government of Vietnam (GOVN), economic restructuring and privatization of health services have been associated with emerging inequities in access to care. A GOVN programme for socio-economic development known as Program 135 (P135) designates communes known to be relatively poor as priority localities for development resources. Under this programme, basic curative and preventive health services, including some prescription drugs, are provided free of charge at commune health centres (CHCs). In an effort to improve the quality of care provided at CHCs, the national Ministry of Health (MOH) has implemented a set of national benchmarks for commune health care, which defines a minimum configuration of equipment, staff, training and other elements of service provision. This research examines the impact of P135 poverty reduction policy, achievement of MOH benchmark indicators and commune socio-economic characteristics on CHC utilization rates in Thai Nguyen Province, Vietnam. The analysis uses administrative data reported from 178 CHCs in Thai Nguyen Province for nine quarters, including 2004, 2005 and the first quarter of 2006. Mixed linear regression models are used to estimate the main and interaction effects on utilization rates of exposure to the P135 policies, achievement of MOH benchmarks, poverty, distance to the district hospital and ethnic composition. Communes that are poor and remote have comparatively high CHC utilization rates. Multivariate regression results suggest that communes exposed to the P135 policy have higher utilization rates, but these effects are conditional upon achievement of benchmark standards, thus perceived quality care enhances CHC utilization. Combining Program P135 with benchmark investment reduced the gap between primary health care utilization in poor communes versus those that are less poor. These commune-level findings suggest that CHC policies differentially benefit poor communities and reduce inequality in use of health care services.
The challenges of generating evidence to guide mechanical circulatory support-based management of advanced heart failure.

This editorial refers to ‘Advanced heart failure: feasibility study of long-term continuous axial flow pump support’† by M.P. Siegenthaler et al. , on page 1031 The heart failure epidemic is increasing globally. The epidemiological transition will, because of (i) a reduction of mortality from infectious diseases and (ii) increased life expectancy, go with an increased mortality risk secondary to cardiovascular diseases including heart failure. Within this background scenario, in the USA and Europe alone, with more than 600 million inhabitants and more than 6 million patients with heart failure, the prevalence of advanced heart failure, constituting 1–10% of the heart failure population, is estimated to total between 60 000 and 600 000 patients. Correspondingly, the evolution of treatment options for advanced heart failure patients over the last decades has been impressive. It includes medical treatment (angiotensin-converting enzyme inhibitors, beta-blockade), defibrillator therapy, heart transplantation, and most recently mechanical circulatory support devices (MCSDs). The comparison of outcomes between different therapies for advanced heart failure has been challenging. For example, heart transplantation has never been tested in a randomized clinical trial because of the obvious survival advantage in the 1970s when compared with medical therapy1 which has been questioned during the last decade.2 Therefore, the clinical decision making algorithm is subject to continuing debate3 and consensus processes, as exemplified by the recent guideline development initiative of the International Society for Heart and Lung Transplantation. In 2001, in the first randomized clinical trial testing the survival benefit of MCSDs in a patient population ineligible for heart transplantation secondary to noncardiac reasons including age and comorbidities, the HeartMate I pulsatile MCSD has been shown to improve survival as well as quality of life.4 Within the evolving family … *Corresponding author. Tel: +1 212 305 0200; fax: +1 212 305 7439. E-mail address : md785{at}columbia.edu
Role of Hpn and NixA of Helicobacter pylori in susceptibility and resistance to bismuth and other metal ions.

Background.Helicobacter pylori produces Hpn, a 60-amino acid, histidine-rich protein that avidly binds nickel and zinc ions, and NixA, a high-affinity nickel transporter in the cytoplasmic membrane. We tested the hypothesis that Hpn and NixA govern susceptibility to metal ions in H. pylori. Materials and Methods. Hpn-negative mutants of four H. pylori strains were constructed by standard allelic exchange techniques to yield isogenic Hpn+/Hpn-deficient pairs. A metal concentration that inhibited growth by 50% (IC50) was calculated for Ni2+, Zn2+, Cu2+, and Co2+ by comparing OD600 of cultures in metal-supplemented and control media. Results. Among all four pairs of isogenic strains, the tolerance for Ni2+ was reduced significantly (p < .001) in the Hpn mutants; the mean IC50 value for wild-type strains was 1.9 mM; for the mutant, it was 0.8 mM. In contrast, growth inhibition by Zn2+ was identical within the fours pairs, as was Cu2+ and Co2+ tolerance in one pair tested. We also found that deletion of the hpn gene increases susceptibility to therapeutic forms of bismuth by testing a mutant and wild-type pair with ranitidine bismuth citrate, bismuth citrate, and four antibiotics. Minimal inhibitory concentrations of ranitidine bismuth citrate dropped from 9.2 to 2.3 μg/ml, and those of bismuth citrate dropped from 7.4 to 3.2 μg/ml (p < .05 for both comparisons), while susceptibility to the antibiotics was unaffected. Disruption of the nixA gene encoding the specific Ni2+ transport protein of H. pylori did not change susceptibility to bismuth. Conclusion. We concluded that bacteria lacking Hpn, cultured in vitro, are more susceptible than is the wild type to bismuth and Ni2+.
Coprocessor design space exploration using high level synthesis

Hardware/software co-design has been an area of research for a few decades. Currently co-design is utilized to create hardware coprocessors for compute intensive tasks of a system (which otherwise, performed in software, will not meet the performance goals). Design of correct hardware coprocessors with area, timing and power constraints is a time consuming task. In this paper, we present a methodology to alleviate this problem up to a certain extent. First, we show how to adopt a high-level synthesis tool in design space exploration to converge towards efficient hardware coprocessors. Second, we show, through a series of case studies that, a system-level approach, keeping platform specific optimizations in mind, can help in doing such an exploration efficiently.
Fun with bananas: novel inputs on enjoyment and task performance

Educators are often finding ways to increase intrinsic motivation for students, one of which is making a task more enjoyable. We hypothesized that using a novel input device would increase enjoyment and performance for a task. In order to test our hypothesis, participants played a game with a keyboard, large pads (created from aluminum foil and cardboard), and bananas as input devices by using a Makey Makey. Our results indicate that enjoyment, interest, excitement, and enthusiasm with bananas was higher than with a standard keyboard input despite a worse performance and lower preference ranking. We discuss potential implications and future work around the implementation of novel input devices.
An efficient built-in self testing for random-access memory

The authors propose a test algorithm for pattern-sensitive faults in large-size RAM with high circuit density. The algorithm tests an n-bit RAM in 195 square root n time to detect both static and dynamic pattern-sensitive faults over the 9-neighbourhood of every memory cell. A 4 Mb RAM can be tested by the proposed algorithm several thousand times faster than the conventional sequential algorithms for detecting pattern-sensitive faults. The test speedup has been achieved by writing a test data simultaneously over many cells, and the stored data are tested simultaneously by a parallel comparator and error detector in a read operation. The existing RAM architecture has been modified very little so that the proposed technique can be implemented very easily even in switched-capacitor DRAM (dynamic random-access memory) with low intercell pitch width. The test procedure has also been applied to built-in self-testing (BIST) and is compared with other BIST implementations. >
Capacitive micromachined ultrasonic transducers for robotic sensing applications

Ultrasonic ranging is the most common method used in robotic systems for distance or proximity sensing. The heart of the method is an ultrasonic transducer that emits and detects ultrasound. There are mainly two types of transducers existing in the market today; piezoelectric and electrostatic. In this paper, we propose the use of a new type of transducer, which is capacitive micromachined ultrasonic transducer (CMUT). CMUTs were introduced about a decade ago, and were shown to be a good alternative for conventional transducers in various aspects, such as sensitivity, efficiency and bandwidth. CMUTs are basically the micromachined versions of the electrostatic transducers. Many enhanced features of the transducer are enabled with the micromachining technology. Micromachining allows miniaturization of the device dimensions and produces capacitive transducers that outperform their piezoelectric and electrostatic counterparts. This paper describes the fabrication process briefly, and the performance of the CMUT transducers is evaluated by demonstrating characterization results. It is also shown that CMUTs can be used for pulse-echo measurements in air up to MHz frequencies.