cssi/SciSciGPT-SciSciNet huggingface dataset:
Evidence of Variation by Race in the Timing of Surgery for Correction of Pediatric Ureteropelvic Junction Obstruction

Purpose: We used a national pediatric database to investigate the association of patient race with timing of surgery for ureteropelvic junction obstruction.Materials and Methods: The Kids’ Inpatient Database is a national database containing 5.5 million pediatric hospitalizations (patients younger than 21 years) during the years 2000 to 2003. We used International Classification of Disease-9 codes to identify patients undergoing pyeloplasty, and investigated patient and hospital factors associated with timing of surgery using multivariable linear and mixed models.Results: A total of 2,989 patients underwent pyeloplasty. Mean patient age was 72.3 months (median 36). Of the patients 69.3% were male and 66.0% were white. White patients were significantly older than nonwhite patients (82.3 vs 52.8 months, p <0.0001). The proportion of patients undergoing surgery during the first 12 months of life also varied by race (31.3% among white vs 46.9% among nonwhite patients, p <0.0001). Other factors associated with...
Epistemological considerations in teaching introductory physics

Epistemological beliefs are beliefs about knowledge and learning. In a physics class, for example, some students might believe learning consists of memorizing facts and formulas provided by the teacher, whereas others might believe it entails applying and modifying their conceptualizations of phenomena. This article explores, in the context of a debate about velocity from the author's high school physics class, how a perspective of students as having epistemological beliefs might influence a teacher's perceptions of students and intentions for instruction. © 1995 John Wiley & Sons, Inc.
Phenotypic Spectrum of Glucose Transporter Type 1 Deficiency Syndrome (Glut1 DS)

Glut1 deficiency syndrome (Glut1 DS) was originally described in 1991 as a developmental encephalopathy characterized by infantile onset refractory epilepsy, cognitive impairment, and mixed motor abnormalities including spasticity, ataxia, and dystonia. The clinical condition is caused by impaired glucose transport across the blood brain barrier. The past 5 years have seen a dramatic expansion in the range of clinical syndromes that are recognized to occur with Glut1 DS. In particular, there has been greater recognition of milder phenotypes. Absence epilepsy and other idiopathic generalized epilepsy syndromes may occur with seizure onset in childhood or adulthood. A number of patients present predominantly with movement disorders, sometimes without any accompanying seizures. In particular, paroxysmal exertional dyskinesia is now a well-documented clinical feature that occurs in individuals with Glut1 DS. A clue to the diagnosis in patients with paroxysmal symptoms may be the triggering of episodes during fasting or exercise. Intellectual impairment may range from severe to very mild. Awareness of the broad range of potential clinical phenotypes associated with Glut1 DS will facilitate earlier diagnosis of this treatable neurologic condition. The ketogenic diet is the mainstay of treatment and nourishes the starving symptomatic brain during development.
Septin-Containing Barriers Control the Differential Inheritance of Cytoplasmic Elements

Summary Fusion of haploid cells of Saccharomyces cerevisiae generates zygotes. We observe that the zygote midzone includes a septin annulus and differentially affects redistribution of supramolecular complexes and organelles. Redistribution across the midzone of supramolecular complexes (polysomes and Sup35p-GFP [PSI+]) is unexpectedly delayed relative to soluble proteins; however, in [ psi- ] × [ PSI+ ] crosses, all buds eventually receive Sup35p-GFP [ PSI+ ]. Encounter between parental mitochondria is further delayed until septins relocate to the bud site, where they are required for repolarization of the actin cytoskeleton. This delay allows rationalization of the longstanding observation that terminal zygotic buds preferentially inherit a single mitochondrial genotype. The rate of redistribution of complexes and organelles determines whether their inheritance will be uniform.
Development and characterization of salivary adenoid cystic carcinoma cell line.

Summary Objective To develop in vitro adenoid cystic carcinoma cell line as a surrogate for functional studies. Materials and methods Cells obtained from a primary ACC of the base of tongue were cultivated in vitro and immortalized with h-TERT. Morphologic, cytogenetic and functional studies were performed. Results Tumor cells were verified by positive reactions to keratin and smooth muscle actin and phenotypic cellular and nuclear features. In-vitro cell growth and colony formation assay supported their tumor nature. Conclusion We authenticated an ACC cell line with hybrid epithelial–myoepithelial feature as a resource for functional experimentation.
Programmed cell death in plants : a pathogen-triggered response activated coordinately with multiple defense functions

In plants, the hypersensitive response (HR) to pathogens involves rapid cell death, which is hypothesized to arise from the activation of a cell death program. We describe mutant A. thaliana plants that contain lesions in a single accelerated cell death (ACD) gene called ACD2 and that bypass the need for pathogen exposure to induce the HR. acd2 plants that develop spontaneous lesions show typical HR characteristics both within the necrotic tissue and within the healthy part of the plant, including: modification of plant cell walls, resistance to bacterial pathogens, and accumulation of defense-related gene transcripts, the signal molecule salicylic acid and an antimicrobial compound. We propose that the ACD2 gene is involved in a pathway(s) that negatively regulates a genetically programmed HR.
Atrial rhythms in response to an early atrial premature depolarization in man

Abstract The effect of an early atrial premature depolarization (APD) on spontaneous atrial rate was assessed in 16 patients in sinus rhythm. At close coupling intervals (range 27 to 48 per cent of the preceding sinus cycle), atrial acceleration was observed for several beats following the APD in 13 patients. On the basis of P wave configuration and the intra-atrial activation sequence, the accelerated beats appeared to originate from the sinus node. Furthermore, this “sinus” acceleration appeared regardless of the site at which the APD was introduced and was unrelated to latency or current strength. The findings are consistent with APD-induced sinus node re-entry, although sinus node pacemaker acceleration and shift is an alternative mechanism. Sinus node re-entry may explain certain instances of “interpolated” APD's and atrial tachyarrhythmias seen clinically.
Effect of gibberellic acid (GA3) on elongation and rooting of ‘St. Julien A’ rootstock in vitro☆

Abstract ‘St. Julien A’ ( Prunus instititia L.) rootstock was induced to proliferate shoots on a modified half-strength Murashige and Skoog (MS) medium. Cultures treated with 12.5 mg l −1 gibberellic acid (GA 3 ) produced elongated shoots suitable for rooting. Elongated shoots were placed in media with indolebutyric acid (IBA) or indole-3-acetic acid (IAA) with or without a 16-day dark incubation. Light (16-h photoperiod) inhibited rooting. IAA (4 mg l −1 ) was ineffective in promoting rooting. Rooting was best when shoots were incubated in the dark with IBA (4 mg l −1 ). GA 3 was deleterious to shoots, causing chlorosis and apical die-back. Light regime interacted with auxin treatments in affecting shoot condition. Shoot condition was better on shoots treated with IBA and dark-incubated; while those treated with IAA were better when light-incubated.
Science Network Focuses on Deep Carbon in the Earth

With carbon playing a critical role related to energy, climate, resources, and life on the planet; with vast stores of it underground; and with many basic questions unanswered about the element, the 10-year international Deep Carbon Observatory (DCO) program, which began in 2009, has ambitious goals to fill in some of those knowledge gaps. To help assess current knowledge and questions about carbon, DCO held a scientific meeting in early March at the U.S. National Academy of Sciences in Washington, D. C., and released a nearly 700-page open access book, Carbon in Earth, which outlines many key issues related to carbon.
Minimally invasive esophagectomy for caustic esophageal stricture in children

Esophageal stricture after lye ingestion in children is the most frequent indication for esophagectomy in children, but this operation entails significant risks for complications. With continuing advances in minimally invasive technology, complex procedures such as esophagectomy can be performed using small incisions, with the aim of reducing morbidity and mortality. Experience with minimally invasive esophagectomy is limited and has involved thoracoscopic dissection with the addition of laparotomy for gastric mobilization. The authors report a case of intractable caustic esophageal stricture in a child treated by a totally minimally invasive esophagectomy through a combined thoracoscopic and laparoscopic approach. In adult patients, this procedure has been associated with decreased hospital stay and more rapid return to normal activities, and we believe similar benefits will be obtained in children. Until further studies are done to show the advantage over the standard open technique, this procedure should be performed only in centers with experience in open esophageal surgery in children as well as by surgeons with advanced thoracoscopic and laparoscopic skills.
Limits to the 1/4 keV Extragalactic X-ray Background

We observed several nearby face-on spiral galaxies with the ROSAT PSPC. The apparent deficiency in soft X-ray surface brightness observed at the outer portion of their disks is consistent with the absorption of the extragalactic soft X-ray background by material associated with these galaxies, and allows us to place a lower limit on the intensity of this cosmologically important background. From the depth of the soft X-ray shadow observed in NGC 3184, a 95% confidence lower limit was derived to be $32 keV cm^{-2} s^{-1} keV^{-1}$ at 1/4 keV. This was obtained by assuming that there is no unresolved 1/4 keV X-ray emission from the outer region of the galaxy which may otherwise partially fill in the shadow: any such emission, or any unresolved structure in the absorbing gas, would imply a larger value. In the deepest exposure to date in this energy range, Hasinger et al. (1993) resolved about $30 keV cm^{-2} s^{-1} keV^{-1}$ at 1/4 keV into discrete sources; our current limit is therefore consistent with an extragalactic origin for all of these sources. Our results can also be directly compared with the corresponding upper limit derived from the ROSAT PSPC detection of soft X-ray shadows cast by high-latitude clouds in Ursa Major, $\simeq 65 keV cm^{-2} s^{-1} keV^{-1}$ at 1/4 keV. The lower and upper limits are only a factor of 2 apart, and begin to provide a reasonable measurement of the intensity of the 1/4 keV extragalactic X-ray background.
Screening of turfgrass species and cultivars for NaCl tolerance

Information regarding the relative levels of salt tolerance between cultivars of Kentucky bluegrass (Poa pratensis L.) is lacking. The objectives of this study were to 1) develop a simple, quick and sensitive method of screening turfgrass species for NaCl tolerance and 2) to compare the relative salt tolerance of five cultivars of Kentucky bluegrass (‘Ram I’, ‘Adelphi’, ‘Baron’, ‘Bensun’, and ‘Nassau’) to other known salt tolerant turfgrass species such as alkalaigrass (Puccinellia distans (L.) Parl. cv. Fults) and two cultivars of red fescue (Festuca rubra L. ‘Dawson’, and ‘Checker’). Alkalaigrass and both cultivars of red fescue retained a high level of salt tolerance compared to the Kentucky bluegrass cultivars. Significant variability in salt tolerance was apparent among the Kentucky bluegrass cultivars with ‘Adelphi’ and ‘Ram I’ exhibiting the best overall tolerance.
Decomposition Pathways of Glycerol via C–H, O–H, and C–C Bond Scission on Pt(111): A Density Functional Theory Study

Glycerol decomposition on Pt(111) via dehydrogenation or C–C bond scission is examined with periodic density functional theory (DFT) calculations. The thermochemistry of dehydrogenation intermediates is first estimated using an empirical correlation scheme with parameters fit to selected DFT calculations; the resulting estimates for the more stable intermediates are refined with full DFT calculations. Bronsted–Evans–Polanyi (BEP) relationships for dehydrogenation and C–C bond scission reactions are developed and used to estimate the kinetics of elementary dehydrogenation and C–C bond scission steps in the reaction network. The combined thermochemical and kinetic analysis implies that glycerol dehydrogenation products at intermediate levels of dehydrogenation are the most thermochemically stable. Additionally, although C–C bond scission transition state energies are high for glycerol and for intermediates at early stages of dehydrogenation, these energies decrease as the intermediates are successively dehy...
On the mechanism of enzyme action. LXV. A cellulolytic enzyme from the mold Poria vaillantii.

Abstract A cellulolytic enzyme was isolated from the culture filtrate of the mold Poria vaillantii . The purified preparation consists of two electrophoretically separable components; the faster migrating component was identified as a cellulase, and the slower-moving as the β-glucosidase, cellobiase. The cellolytic enzyme is stable over the pH range of 4.0–6.0, and has a pH optimum of 3.2. The effects of certain metal ions and of oxidizing and reducing agents were studied. It was found that the presence of thiol groups are essential for the cellulolytic enzyme.
Human cord blood stem cell paracrine factors activate the survival protein kinase Akt and inhibit death protein kinases JNK and p38 in injured cardiomyocytes

Abstract Background aims We hypothesized that paracrine factors from human umbilical cord blood mononuclear cells (hUCBC) activate in injured cardiomyocytes the survival protein kinase Akt and limit activation of death protein kinases JNK and p38. Methods We treated hUCBC with H 2 O 2 and measured growth factors and cytokines secreted by hUCBC. We then treated cardiomyocytes with H 2 O 2 for 24 h and measured Akt, JNK and p38 activation by means of Western blots. We also measured myocyte viability and apoptosis with the use of fluorescence-activated cell-sorting cytometry. We then investigated myocytes treated for 24 h with H 2 O 2 plus hUCBC and myocytes without hUCBC or H 2 O 2 . Four million hUCBC were placed in transwells permeable only to hUCBC paracrine factors, and the transwells were placed in flasks with H 2 O 2 +Dulbecco's modified Eagle's medium or in flasks with myocytes plus H 2 O 2 +Dulbecco's modified Eagle's medium. Results hUCBC increased secretion during H 2 O 2 of hepatocyte growth factor by 338%, insulin-like growth factor by 200%, interleukin-4 by 200%, vascular endothelial cell growth factor by 192%, placental growth factor by 150%, interleukin-10 by 150% and angiogenin by 121%. H 2 O 2 increased myocyte JNK activation by 237% and p38 activation by 60%, decreased myocyte viability by 38% and increased necrosis by 34% (all P 2 O 2 Akt activation by ≥25%, decreased JNK and p38 activation by >35%, increased viability by >22% and decreased apoptosis by >33% (all P 2 O 2 decrease of myocyte viability. Addition of JNK inhibitor SP600125 or p38 inhibitor SB203580 to myocytes plus H 2 O 2 prevented H 2 O 2 decrease in viability and increased hUCBC beneficial effects. Conclusions During free radical stress, hUCBC paracrine factors activate myocyte Akt, which increases myocyte viability by decreasing activation of death-promoting protein kinases JNK and p38.
Clay Minerals at a Pennsylvanian Disconformity1

At the Desmoinesian-Missourian disconformity in southeastern Kansas a fossil soil zone is recognized by variations in clay mineralogy in the uppermost Desmoinesian Holdenville shale, which underlies basal Missourian Hepler sandstone. The clay fraction of the overlying basal Missourian Hepler sandstone contains kaolinite, slightly hydrated illite, quartz, and vermiculite. Chlorite (rather than vermiculite) is present in shaly portions of the basal Hepler sandstone. Clay-size minerals of the typical Holdenville shale (marine) are predominantly illite, chlorite, quartz, feldspar, and a very small quantity of kaolinite. The clay-mineral assemblages in samples from the upper part of the Holdenville shale indicate hydration of illite, sporadic increase in kaolinite, possible decrease in feldspar, and progressive modification and destruction of chlorite resulting in production of mixed-layer minerals.
Using Self-Regulated Learning Methods to Increase Native American College Retention:

A big challenge facing colleges and university programs across the United States is retaining students to graduation. This is especially the case for Native American students, who have had one of t...
Band Structures and Pseudopotential Form Factors for Fourteen Semiconductors of the Diamond and Zinc-blende Structures

Pseudopotential form factors and band structures are determined for 14 semiconductors of the diamond and zincblende structures: AlSb, CdTe, GaAs, GaP, GaSb, Ge, InAs, InP, InSb, Si, Sn, ZnS, ZnSe, and ZnTe. Experimental values of the splitting of energy levels in the crystal are used. The form factors appear to be accurate to 0.01 Ry and yield energy bands which agree with experiment to within \ensuremath{\sim}0.01 Ry near the band gap and \ensuremath{\sim}0.04 Ry over a range of 1 Ry. For some of these substances these are the first band structures to be calculated.
Switching points of view in spatial mental models.

In six experiments, subjects read narratives describing varying spatial scenes with more than one point of view. They were probed with questions about objects located in six directions from each character’s point of view. Subjects’ response times were consistent with a one place-one perspective rule. They seemed to form separate mental models for separate places and to take a character’s perspective when there was only one relevant character in a scene, but they seemed to take a neutral perspective when there was more than one probed point of view, rather than switch perspectives.
A novel system to identify Myb target promoters in friend murine erythroleukemia cells.

Abstract ABSTRACT Friend murine erythroleukemia (MEL) cells provide an early erythroid precursor model that can be induced to terminally differentiate in cell culture and has been used to study erythroid differentiation as well as multistage tumorigenesis. During the chemically induced differentiation of MEL cells, expression of the c- myb protooncogene is downregulated in a biphasic fashion and forced expression of c- myb is able to block the differentiation process, suggesting that c- myb activity may be limiting for differentiation in MEL cells. We have recently produced stable transfectants in the C19 MEL cell line that carry a dominant interfering myb allele (MEnT) under the control of an inducible mouse metallothionein I (MTH) promoter. Upon inducing expression of MEnT, transfected cells enter a differentiation program and begin to produce α-globin mRNA, assemble hemoglobin, and stop proliferating. Differential display was used to compare mRNA expression between parental C19 MEL cells induced to differentiate with hexamethylene bisacetamide (HMBA) and stable transfectants induced to differentiate via expression of MEnT to identify potential Myb target promoters. We identified six candidate cDNAs in this fashion and present evidence that two of these represent genes that are dependent on c-Myb activity for maximal expression in MEL cells.
Degradation and Disposal of Scepter Herbicide by Hydrogen Peroxide-Catalyzed Ozonation

Studies were conducted to determine the ability of ozonation catalyzed by hydrogen peroxide (H2O2) to degrade solutions of Scepter herbicide (imazaquin). Scepter herbicide solutions were rapidly degraded using a range of solution temperatures (1−35 °C) and H2O2 concentrations (0−69 mM). The most rapid degradation occurred when the [H2O2] was 0.2 mM; imazaquin was also rapidly degraded in the absence of H2O2. The ozonation times required for 90% removal of the herbicide were typically < 15 min. Approximately 10.5 ± 4.4% (quinoline ring) to 17.1 ± 7.8% (carboxylic acid) of [14C]imazaquin was oxidized to 14CO2 when solutions with pH values ranging from 5.5 to 8.5 were ozonated for 0.5 h at 20 °C. Resulting ozonation products, which included nitrate, exhibited rapid biomineralization when added to two soils. The ozonation products of Scepter herbicide were not phytotoxic when applied to cotton, corn, and soybean seedlings at application rates equivalent to 34 g a.i./ha. Keywords: Imazaquin; ozonation; pestici...
Rheological properties of poly(dimethylsiloxane) filled with fumed silica: I. Hysteresis behaviour

Abstract The apparent viscosity and primary normal stress difference were measured for dispersions of fumed silica in poly(dimethylsiloxane). Dispersions with less than 4.75% by weight of filler exhibit hysteresis in both the viscosity and normal stress, when the shear rate was increased and then decreased in discrete steps. The shape of the hysteresis loops were sensitive to the details of the deformation history. By using the appropriate deformation history, the material properties determined during the increasing shear rate part of the hysteresis experiment compare favourably with the steady-state rheological properties. The rheological properties of the dispersion were quite sensitive to the age of the fluid with no hysteresis behaviou exhibited by dispersions less than three days old. For dispersions with at least 4.75% by weight of fumed silica, neither the apparent viscosity nor the primary normal stress coefficient exhibited significant hysteresis behaviour. The relationship between the observed rheological behaviour and the dispersion's microstructure is discussed.
Dissociation in posthypnotic amnesia: knowing without knowing.

Abstract Research on the relationship of dissociation to hypnosis has, for the most part, been limited to the use of the “hidden observer” paradigm. The generality of this relationship was tested by using a posthypnotic amnesia task in which subjects were asked to guess a pattern of color squares after having reported posthypnotic amnesia for this pattern. Guesses were significantly more accurate than chance level and than the number of guesses reported by non-hypnotized subjects who were asked to predict the responses of the hypnotized subjects. The results are consistent with a dissociation interpretation of hypnosis.
Is Behaviorism Becoming a Pseudo-Science?: Power Versus Scientific Rationality in the Eclipse of Token Economies by Biological Psychiatry in the Treatment of Schizophrenia

Wyatt and Wong argue that biological psychiatry's power, not its scientific merits, explain token economies' eclipse by biological treatments of schizophrenia. However, Wyatt and Wong's critiques of biological psychiatry, while partly true, ignore offsetting strengths and achievements as well as plausibility arguments that schizophrenia is partly biological; behavioral theory offers no cogent alternative account of etiology. Moreover, token-economy research fails to establish generalizability of changes to post-ward environments. Even Paul and Lentz's (1977) definitive research on token-economy treatment of schizophrenia failed to show generalization of changes to community life, and in fact, due to an inadvertent "natural experiment," reveals the instability of behavioral changes even after years of treatment. To preserve their belief system, behaviorists seem in danger of turning behaviorism into a pseudoscience defended by ad hoc hypotheses.
Secondary Structure and Stability of Marsh Grapefruit Thermolabile Pectinesterase

Thermolabile pectinesterase (TL-PE) was inactivated completely after 8 h of dialysis at pH 3.3 but retained activity at pH 4.1 and pH 7.0. Circular dichroism (CD) spectra and secondary structural analysis showed similar secondary structure between pH 7.0, pH 4.1, and pH 3.3. The CD spectra of TL-PE were compared at pH 7.0 and 4.1 and between 25 and 70 °C. Heating TL-PE at pH 7.0 and 4.1 resulted in irreversible protein precipitation. The thermal transition temperature for destabilization of TL-PE structure occurs at a lower temperature at pH 4.1 than at pH 7.0, suggesting some change in the secondary structure of TL-PE. Keywords: Pectinesterase; stability; activity; thermal transition; denaturation
Heat transfer enhancement by delta-wing vortex generators on a flat plate: Vortex interactions with the boundary layer

New data are presented that demonstrate a 50% to 60% enhancement of average heat and mass transfer for flow over a flat plate at low Reynolds numbers, using delta-wing vortex generators. The mechanisms responsible for the enhancement are determined, and a single parameter for estimating their effect is established. Using a straightforward method for evaluating this parameter from flow visualization data, optimal delta-wing geometries were found for Reynolds numbers of 600, 800, and 1000 based on wing-chord length. The results were also used to develop a clearer understanding of the interactions between the vortex and boundary layer. When a high-circulation vortex is placed near the edge of the boundary layer, it effectively thins the boundary layer; the vortex advects free-stream fluid into the temperature or species boundary layer. Vortices should be generated in a common inflow arrangement so that induced velocities keep the vortices near the boundary layer.
Synthesis and Molecular Modeling Provide Insight into a Pseudomonas aeruginosa Quorum Sensing Conundrum

The triphenyl amide/ester 12 was originally reported to be a potent mimic of the natural 3-oxo-dodecanoyl homoserine lactone quorum sensing molecule in Pseudomonas aeruginosa. However, explicit synthesis/chemical characterization was lacking, and a later report providing protein crystallographic data inferred 12 to be incorrect, with 9 now being the surmised structure. Because of these inconsistencies and our interest in quorum sensing molecules utilized by Gram-negative bacteria, we found it necessary to synthesize 9 and 12 to test for agonistic activity in a P. aeruginosa reporter assay. Despite distinct regiochemical differences, both 9 and 12 were found to have comparable EC50 values. To reconcile these unanticipated findings, modeling studies were conducted, and both compounds were revealed to have comparable properties for binding to the LasR receptor.
A Comparison of the Response of Cotton and Milkweed to Selected Swelling and Crosslinking Treatments

Research on experimental fabrics knitted from yams containing cotton and common milkweed fibers has been extended to selected swelling treatments. Results are presented on the response of cotton / milkweed blends to caustic and ammonia mercerization, and to subsequent crosslinking. The physical properties of the mercerized fabrics are described before and after crosslinking with dimethyloldihydroxyethyleneurea. Dif ferences are noted on the morphology and chemical properties of the cotton and milkweed fibers after the chemical treatments.
Inferring climate change from stable isotope compositions of ancient speleothems on Earth: possible implications for climatic reconstructions elsewhere in the solar system

The stable isotopic compositions of Late Pleistocene and Holocene cave deposits (speleothems) are valuable proxies for high-resolution climate reconstructions on Earth, in particular with respect to changes in vegetation, temperature, atmospheric composition, and monsoonal precipitation. On the basis of U-Th dating and annual growth bands, researchers have shown that many speleothems can grow continuously for thousands to hundreds of thousands of years. Depending on the growth rate of a given speleothem, and its sensitivity to environmental changes on the surface, it may record climatic shifts on timescales ranging from weeks to years. This has made modern speleothems particularly useful for applications ranging from paleotempestology to studies of glacial-interglacial transitions. It stands to reason, then, that ancient speleothems might hold valuable information about climatic change in the deep geologic past - at resolutions that have been previously unattainable using other materials (e.g. paleosols). Here we report carbon and oxygen isotopic signatures obtained from an Early Permian flowstone that was extracted from a shallow paleocave in Oklahoma. We interpret the stable isotope data to reflect progressive aridification and devegetation, possibly as a result of CO2 forcing. This interpretation is consistent with independent paleoclimatic data from coeval sediments in the region, and is also broadly consistent with similar records from modern, low-latitude speleothems. The fact that isotopic signatures are preserved in speleothems up to a few hundred million years old indicates that it might be possible to retrieve similar climatic data from ancient carbonate deposits elsewhere in the solar system.
Analyticity and unitarity of general transition amplitudes

The analyticity and unitarity hypotheses for a general transition amplitude are formulated carefully for a world containing only one type of particle. From these hypotheses follows the conclusion that the general transition amplitude has no singularities on the positive real energy axis other than isolated singularities at physical thresholds. The analytic behavior near each such singularity is exhibited. At thresholds for processes involving an odd number of particles, the behavior is logarithmic.
Fixed-Dose Combination Therapy With Trandolapril and Verapamil SR Is Effective in Primary Hypertension

We assessed the efficacy of monotherapy with trandolapril, an angiotensin converting enzyme (ACE) inhibitor, and of verapamil slow-release (SR), a calcium antagonist, each in a range of three doses as monotherapy, and in the nine possible combinations of therapy in patients with stage I to III diastolic hypertension. After 4 weeks of single-blind placebo, 746 patients in 39 study centers were randomized to one of the 16 double-blind treatments for 6 weeks (placebo; verapamil SR monotherapy 120, 180, or 240 mg; trandolapril monotherapy 0.5, 2, or 8 mg; and trandolapril/verapamil SR combinations 0.5/120, 0.5/180, 0.5/240, 2/120, 2/180, 2/240, 8/120, 8/180, or 8/240 mg. Both mono- and combination therapies achieved the primary efficacy parameters: lowered supine diastolic blood pressure (at trough) more than placebo, P 0.52 and had higher percentages of responders as compared with placebo (P < .01, < .05). Supine systolic blood pressures were lowered more by combination therapy than the respective monotherapies, P < .05, P < .01, except the 8/120 combination. Combination therapy was more effective than monotherapy for sitting diastolic blood pressure, P < .05. The percentage of patients with adverse reactions were similar for mono- and combination therapy. Trandolapril had a greater "apparent" incremental effect on the systolic blood pressure reductions than verapamil SR.
A technique for the growth of Cu and Cu-Al bicrystals

Abstract A solidification method using a specially designed graphite split mold is described by which bicrystals of pure copper and copper-aluminium alloys can be grown.
Prevalence and Characteristics of Left Ventricular Noncompaction in a Community Hospital Cohort of Patients with Systolic Dysfunction

BACKGROUND Left ventricular noncompaction (LVNC) is felt to be a rare form of cardiomyopathy, although its prevalence in a nonreferred population is unknown. We examined the prevalence and clinical characteristics of LVNC in a community hospital cohort of adult patients with echocardiographic evidence of left ventricular (LV) systolic dysfunction. METHODS All adult echocardiograms with global LV dysfunction and an LVEF < or = 45% over a 1-year period were reviewed for signs of LV noncompaction. Its presence was confirmed by the consensus of at least 2/3 readers specifically searching for this using standard criteria for noncompaction. RESULTS A 3.7% prevalence of definite or probable LVNC was found in those with LVEF < or = 45% and a 0.26% prevalence for all patients referred for echocardiography during this period. This is appreciably higher than prior reports from tertiary centers. CONCLUSION Noncompaction may not be a rare phenomenon and is comparable to other more widely recognized but less common causes of heart failure such as peripartum myopathy, connective tissue diseases, chronic substance abuse and HIV disease.
Atypical Chronic Headache and Recurrent Facial Ecchymosis: A Case Report

We present the case of a 57-year-old woman with chronic paroxysmal headache and recurrent facial ecchymosis. The headaches are chronic, unilateral, sharp, electric shock-like, of short duration, without nausea nor vomiting, ptosis, miosis, conjunctival injection nor tearing. The facial ecchymoses have been mainly located in the periorbital and epicanthal areas. General, neurological and ophthalmological examinations were unremarkable. Work-up was unremarkable, including negative skin biopsy. The headache was difficult to include in any particular category given the atypical features, but the characteristics were suggestive of a variant of trigeminal autonomic cephalalgia with lack of responsiveness to indomethacin. We discuss the possible pathogenetic mechanism of the occurrence of facial ecchymosis in primary headache disorders.
Acute myelomonocytic leukemia with double minute chromosomes and a normal karyotype

A case of acute myelomonocytic leukemia in a 74-year-old male patient is described whose bone marrow cells had a normal male karyotype but with double minutes chromosomes (DM). The patient had no history of exposure to mutagenic or carcinogenic agents, or a history of other malignancies. The clinical and etiologic implications of DM as a sole karyotypic anomaly in the leukemic cells are discussed.
48 The effects of environmental factors on the resumption of photosynthetic activity of cyanobacterial mats following rehydration

Extensive cyanobacterial mats cover the intertidal zone near Guerrero Negro, Baja California Sur. These mats are exposed to extreme desiccation and osmotic stress between tidal flows and rains, and spend most of the time dry and metabolically inactive. Therefore, periods of hydration are extremely important for growth as well as for repair of cellular damage from desiccation and ultraviolet radiation (UVR) accrued when the mat is dry. PAM fluorometry in conjunction with carbon incorporation assays were used to determine the effects of salinity, irradiance and UVR on the recovery of photosynthetic activity in these mats after an extended period of desiccation. The mat used in our study was primary composed of Lyngbya sp. Photosynthetic activity recovery rates (using PAM fluorometry) decreased with increasing salinity. This trend was similar under high and low light intensities, but rates were significantly lower under low light. Alternatively, the carbon incorporation method showed rates increased faster in salinities of 27 and 55 ppt than in salinities of 0 or 75 ppt. The Lyngbya mat also failed to recover photosynthetic potential in the dark. Although these mats recovered faster under high intensity light, the effect of salinity on photosynthesis is more complex. UVR did not affect the recovery of photosynthetic activity, no matter which method was used. This lack of effect is most likely due to the high content of the UVR screening pigment, scytonemin, in the upper layer of the mat.
Locus of distributed lag effect in free recall

In two experiments subjects free recalled object phrases of sentences that were repeated twice at lags of 3, 8, and 16 intervening events. In Experiment I an image task was used to restrict the time available to actively rehearse and organize either the first, the second, or both occurrences at all lag conditions. Lag effects were eliminated whenever time available for rehearsal and organization was restricted for the second occurrence. In Experiment II a completion task was used and actual presentation time was manipulated on the first and second occurrence. Under the 3–9 condition the first occurrence was presented for 3 sec and the second for 9 sec. The reverse was true for the 9-3 condition. As expected, lag effects were obtained only under the 3–9 condition. Results of both studies support the differential-organization hypothesis.
Ionic conductivity of a poly(vinylpyridinium)/silver iodide solid polymer electrolyte system

Abstract A series of quaternized poly(2-vinylpyridine) (PVP) polymers has been synthesized with the general formula [(PVP) R ]I, where R =H, Me, Bu. Addition of AgI to the polymers results in new silver ion conducting solid polymer materials. Conductivities as high as 6×10 −3 S/cm have been observed for the 3:1 AgI/[(PVP)Me]I composition. Analogous materials with a 3:1 composition for the protonated and butyl-substituted polymers display lower conductivities near 2×10 −4 S/cm. Conductivity studies, as a function of temperature, show these materials to be thermodynamically stable with a low activation energy for ion conduction. Differential scanning calorimetry experiments suggest that a new phase with the general formula (PVP) R Ag 3 I 4 forms with silver ions in a new amorphous state.
Lithospheric thickness in the western Pacific

Abstract Rayleigh wave phase velocities were determined by the single-station method for ten paths in the western Pacific. The data show that even 100 m.y. after formation, the phase velocity and upper-mantle structure are still dependent upon age. Inversion of the data gave a model with a lithospheric thickness of 76 km at 100 m.y., increasing to 104 km at 150 m.y., measured from the base of the crust.
Imaging of biomedical turbid tissue using catheter swept-source optical coherence tomography

We present an optical fiber catheter-based complex swept-source optical coherence tomography (OCT) system for imaging of biomedical turbid tissue. A quadrature Mach-Zehnder interferometer based on multi-port fiber couplers was employed in our complex swept-source OCT system. A variety of fiber probes were developed for the different types of biomedical application. We demonstrate OCT images of human skin and deeper tissues by using the fiber probes and our OCT engine. The results show that catheter-based swept source OCT is an effective imaging modality for real-time diagnosis and in vivo applications on human turbid tissue.
Cyberpunk Cities Science Fiction Meets Urban Theory

The science fiction subgenre of cyberpunk developed in the 1980s and 1990s with a strong interest in urban settings. A reading of important cyberpunk novels shows the way in which the ideas of form...
Atrial fibrillation increases production of superoxide by the left atrium and left atrial appendage: role of the NADPH and xanthine oxidases

Background— Atrial fibrillation (AF) is associated with an increased risk of stroke due almost exclusively to emboli from left atrial appendage (LAA) thrombi. Recently, we reported that AF was associated with endocardial dysfunction, limited to the left atrium (LA) and LAA and manifest as reduced nitric oxide (NO·) production and increased expression of plasminogen activator inhibitor-1. We hypothesized that reduced LAA NO· levels observed in AF may be associated with increased superoxide (O2·−) production. Methods and Results— After a week of AF induced by rapid atrial pacing in pigs, O2·− production from acutely isolated heart tissue was measured by 2 independent techniques, electron spin resonance and superoxide dismutase–inhibitable cytochrome C reduction assays. Compared with control animals with equivalent ventricular heart rates, basal O2·− production was increased 2.7-fold (P<0.01) and 3.0-fold (P<0.02) in the LA and LAA, respectively. A similar 3.0-fold (P<0.01) increase in LAA O2·− production wa...
The association of personality disorders with the prospective 7-year course of anxiety disorders

Background. This study prospectively examined the natural clinical course of six anxiety disorders over 7 years of follow-up in individuals with personality disorders (PDs) and/or major depressive disorder. Rates of remission, relapse, new episode onset and chronicity of anxiety disorders were examined for specific associations with PDs. Method. Participants were 499 patients with anxiety disorders in the Collaborative Longitudinal Personality Disorders Study, who were assessed with structured interviews for psychiatric disorders at yearly intervals throughout 7 years of follow-up. These data were used to determine probabilities of changes in disorder status for social phobia (SP), generalized anxiety disorder (GAD), obsessive-compulsive disorder (OCD), post-traumatic stress disorder (PTSD), panic disorder and panic disorder with agoraphobia. Results. Estimated remission rates for anxiety disorders in this study group ranged from 73 % to 94 %. For those patients who remitted from an anxiety disorder, relapse rates ranged from 34 % to 67 %. Rates for new episode onsets of anxiety disorders ranged from 3 % to 17 %. Specific PDs demonstrated associations with remission, relapse, new episode onsets and chronicity of anxiety disorders. Associations were identified between schizotypal PD with course of SP, PTSD and GAD ; avoidant PD with course of SP and OCD ; obsessive-compulsive PD with course of GAD, OCD, and agoraphobia ; and borderline PD with course of OCD, GAD and panic with agoraphobia. Conclusions. Findings suggest that specific PD diagnoses have negative prognostic significance for the course of anxiety disorders underscoring the importance of assessing and considering PD diagnoses in patients with anxiety disorders.
Thermal entrance effects in stratified gas—liquid flow: experimental investigation

Abstract A study of heat transfer in the thermal entrance region for horizontal concurrent airwater flow over a flat plate has been carried out to complement theoretical studies of the phenomenon. Measurements of the heat transfer characteristics and fluid mechanics parameters have been made for constant wall temperature and constant wall heat flux boundary conditions. The results for smooth surfaces and for hydrodynamically unstable liquid films are compared with the theory for non-rippling films. Theory and experiment are compared in terms of dimensionless parameters that characterize the system, in terms of wall temperature and wall heat flux profiles and as local Nusselt numbers vs. position.
Throughput and delay analysis of two-tier slotted Aloha

Convergecast is a communication structure for wireless sensor networks (WSN) in which data flow from multiple nodes into one node. We use a two-tier slotted Aloha model to analyze the throughput and average packet delay of a convergecast mode based on slotted Aloha. In our model each node has a buffer and we use Equilibrium Point Analysis (EPA) approach to study the model. Rayleigh fading is assumed in the analysis.
When bivalves took over the world

The end-Permian mass extinction is commonly portrayed not only as a massive biodiversity crisis but also as the time when marine benthic faunas changed from the Paleozoic Fauna, dominated by rhynchonelliform brachiopod taxa, to the Modern Fauna, dominated by gastropod and bivalve taxa. After the end-Permian mass extinction, scenarios involving the Mesozoic Marine Revolution portray a steady increase in numerical dominance by these benthic molluscs as largely due to the evolutionary effects of an “arms race.” We report here a new global paleoecological database from study of shell beds that shows a dramatic geologically sudden earliest Triassic takeover by bivalves as numerical dominants in level-bottom benthic marine communities, which continued through the Early Triassic. Three bivalve genera were responsible for this switch, none of which has any particular morphological features to distinguish it from many typical Paleozoic bivalve genera. The numerical success of these Early Triassic bivalves cannot be attributed to any of the well-known morphological evolutionary innovations of post-Paleozoic bivalves that characterize the Mesozoic Marine Revolution. Rather, their ability to mount this takeover most likely was due to the large extinction of rhynchonelliform brachiopods during the end-Permian mass extinction and aided by their environmental distribution and physiological characteristics that enabled them to thrive during periods of oceanic and atmospheric stress during the Permian/Triassic transition.
Infection Courts and Timing of Infection of Apple Fruit by Phacidiopycnis washingtonensis in the Orchard in Relation to Speck Rot During Storage

Abstract Phacidiopycnis washingtonensis is the cause of speck rot, a recently reported postharvest fruit rot disease of apple. The pathogen is believed to incite infections in the field, and disease symptoms become evident only during storage. To determine the timing of apple fruit infection in relation to development of speck rot in storage, ‘Red Delicious’ and ‘Fuji’ apple fruit were inoculated in the orchard with P. washingtonensis at different times during the growing season, harvested, and monitored for decay development during storage at 0°C. Fruit inoculated in both field and laboratory also were used to identify the infection courts and mode of apple fruit penetration by P. washingtonensis. In all 3 years, stem-end speck rot and calyx-end speck rot developed during cold storage on fruit inoculated during the growing season, regardless of inoculation time; and the incidence of total speck rot in storage increased as the fruit inoculation time approached harvest. On fruit floral parts, the pathogen ...
Novel surrogate markers for acute brain damage: cerebrospinal fluid levels corrrelate with severity of ischemic neurodegeneration in the rat.

Previously, we identified proteins released from degenerating cultured cortical neurons as novel cerebrospinal fluid (CSF) markers for acute brain injury in the rat. Here, we investigate relationships between CSF changes in these novel markers and the severity of acute ischemic brain injury. Rats underwent sham surgery or 3,6,8, or 10 mins of transient global forebrain ischemia. At 48 h after insult, CSF levels of 14-3-3b, 14-3-3f, and calpain cleavage products of a-spectrin and tau were quantified. Regional acute neurodegeneration was assessed by Fluoro-Jade and silver impregnation staining, and confirmed by immunohistochemical detection of the activation of calpain and caspase, cysteine proteases involved in neurodegenerative signaling. Ischemic neurodegeneration and activation of at least one cysteine protease were observed in the hippocampal CA1 sector, dentate hilus, caudate nucleus, parietal cortex, thalamus, and inferior colliculus. As expected, the total number of degenerating cells increased as a function of ischemia duration. Cerebrospinal fluid levels of the four marker proteins increased markedly after ischemia, and rose in proportion with its duration. Irrespective of the length of ischemia, CSF levels of the neuron-enriched proteins 14-3-3b and calpain-cleaved tau correlated significantly with the magnitude of acute ischemic neurodegeneration. Additionally, CSF levels of the two proteins correlated with one another. These results show that certain proteins released from degenerating neurons are CSF markers for brain injury in the rat whose levels reflect the severity of acute ischemic neurodegeneration. Measurement of 14-3-3b and calpain-cleaved tau may be useful for the minimally invasive diagnosis, prognosis, and therapeutic evaluation of acute brain damage. Journal of Cerebral Blood Flow & Metabolism advance online publication, 18 May 2005; doi:10.1038/sj.jcbfm.9600138