cssi/SciSciGPT-SciSciNet huggingface dataset:
Electrocardiogram Signals to Assess Zebrafih Heart Regeneration: Implication of Long QT Intervals

Zebrafish is an emerging model system for cardiac conduction and regeneration. Zebrafish heart regenerates after 20% ventricular resection within 60 days. Whether cardiac conduction phenotype correlated with cardiomyocyte regeneration remained undefined. Longitudinal monitoring of the adult zebrafish heart (n = 12) was performed in terms of atrial contraction (PR intervals), ventricular depolarization (QRS complex) and repolarization (heart rated corrected QTc interval). Baseline electrocardiogram (ECG) signals were recorded one day prior to resection and twice per week over 59 days. Immunostaining for gap junctions with anti-Connexin-43 antibody was compared between the sham (n = 5) and ventricular resection at 60 days post-resection (dpr) (n = 7). Heart rate variability, QTc prolongation and J-point depression developed in the resected group but not in the sham. Despite a trend toward heart rate variability in response to ventricular resection, the differences between the resected and sham fish were, by and large, statistically insignificant. At 10 dpr, J-point depression was statistically significant (sham: −0.179 ± 0.061 mV vs. ventricular resection: −0.353 ± 0.105 mV, p 0.05, n = 3; regeneration: −0.209 ± 0.119 mV, p > 0.05, n = 4). Despite positive Connexin-43 staining in the regeneration group, QTc intervals remained prolonged (sham: 325 ± 42 ms, n = 5; scar tissues: 534 ± 51 ms, p < 0.01, n = 3; regeneration: 496 ± 31 ms, p < 0.01, n = 4). Thus, we observed delayed electric repolarization in either the regenerated hearts or scar tissues. Moreover, early regenerated cardiomyocytes lacked the conduction phenotypes of the sham fish.
Sirtuins: Longevity focuses on NAD+

NAD+-dependent deacetylases of the sirtuin family have long been implicated in lifespan regulation, and the significance and molecular mechanism (or mechanisms) of this effect have engendered spirited debate. Two articles now spotlight the catabolism of NAD+ itself as a mediator of lifespan regulation.
A truncated Tn916-like element in a clinical isolate of Enterococcus faecium

Abstract A 58.7-Kb nonconjugative plasmid (pKQ1) previously reported in a clinical isolate or Enterococcus faecium was found to contain both a tetM and an erythromycin resistance (erm) determinant. The plasmid contained a region homologous to the A, F, H, and G Hinc II fragments of Tn916. However, the 4.8-kb B fragment of Tn916 which contained the tetM determinant was replaced by a 7.3-kb fragment, and the 3.6-kb HincII C fragment of Tn916 was missing. An element homologous to Tn917 was juxtaposed to the truncated Tn916-like element. The Tn917-like element was similar in size to the erm transposon Tn917 as determined by a ClaI restriction digest which spanned approximately 99% of the transposon. When Bacillus subtilis or Streptococcus sanguis were transformed with pKQ1, no zygotically induced transposition of the tetM element was detected. Similarly no transposition of the Tn917-like element was detected.
Chronic exposure of killifish to a highly polluted environment desensitizes estrogen-responsive reproductive and biomarker genes.

Abstract Reproductive and endocrine disruption is commonly reported in aquatic species exposed to complex contaminant mixtures. We previously reported that Atlantic killifish ( Fundulus heteroclitus ) from the chronically contaminated Newark Bay, NJ, exhibit multiple endocrine disrupting effects, including inhibition of vitellogenesis (yolk protein synthesis) in females and false negative vitellogenin biomarker responses in males. Here, we characterized the effects on estrogen signaling and the transcriptional regulation of estrogen-responsive genes in this model population. First, a dose–response study tested the hypothesis that reproductive biomarkers ( vtg1 , vtg2 , chg H , chg Hm , chg L ) in Newark Bay killifish are relatively less sensitive to 17β-estradiol at the transcriptional level, relative to a reference (Tuckerton, NJ) population. The second study assessed expression for various metabolism ( cyp1a , cyp3a30 , mdr ) and estrogen receptor ( ER α , ER βa , ER βb ) genes under basal and estrogen treatment conditions in both populations. Hepatic metabolism of 17β-estradiol was also evaluated in vitro as an integrated endpoint for adverse effects on metabolism. In the third study, gene methylation was evaluated for promoters of vtg1 (8 CpGs) and vtg2 (10 CpGs) in both populations, and vtg1 promoter sequences were examined for single nucleotide polymorphism (SNPs). Overall, these studies show that multi-chemical exposures at Newark Bay have desensitized all reproductive biomarkers tested to estrogen. For example, at 10 ng/g 17β-estradiol, inhibition of gene induction ranged from 62% to 97% for all genes tested in the Newark Bay population, relative to induction levels in the reference population. The basis for this recalcitrant phenotype could not be explained by a change in 17β-estradiol metabolism, nuclear estrogen receptor expression, promoter methylation (gene silencing) or SNPs, all of which were unaltered and normal in the Newark Bay population. The decreased transcriptional sensitivity of estrogen-responsive genes is suggestive of a broad effect on estrogen receptor pathway signaling, and provides insight into the mechanisms of the endocrine disrupting effects in the Newark Bay population.
Stress distributions at the abrasive-matrix interface during tool wear in bound abrasive grinding : A finite element analysis

Abstract In bound-abrasive grinding, the abrasive particles are subjected to normal and frictional forces due to their interactions with the workpiece. These forces generate stresses at the abrasive particle-matrix interface (also referred to as “the interface” in the following text). Debonding, or fallout of abrasive particles, will be affected by the stress state at the interface, which is determined by the load on the particle, the wear of matrix material around each individual particle, and the wear of the particle itself. A two-dimensional finite element model is established to calculate the stress distributions at the interface. Given the particle geometry and the load distributed around the abrasive tip, the calculations show that a high stress state occurs at the interface close to the surface of the matrix, i.e. the junction of the matrix surface and the interface. The magnitude of stress at the tension side of the particle increases drastically when the matrix is worn away evenly on both sides of the particle. However, wear of the bond along only the leading or tension side of the interface does not affect the stress distribution significantly. Wear of the abrasive particle itself has only limited influence on the stress distribution.
Understanding physical factors associated with participation in community ambulation following stroke

Purpose. This study examined the association between impaired physical function and participation in community ambulation following stroke. We hypothesised that participation would be significantly less following stroke, and that physical impairments would be associated with participation.Method. Using a case–control design 30 survivors of stroke aged 45 and older and 30 controls provided health status information and a self-report of participation in community ambulation (number of trips and walking-related activities (WRA) reported prospectively over a 12-day period). The association of physical impairments (strength, range of motion, sensation, muscle tone, vision, and activity limitations (gait speed and performance on complex walking tasks)) with level of participation was analysed using negative binomial regression and goodness of fit.Results. Participants included 30 individuals with and 30 without stroke, average age 68 years, majority were Caucasian women. Average time since stroke was 40 months....
THE TWISTS AND TURNS OF SPHINGOLIPID PATHWAY IN GLUCOSE REGULATION

Palmitic acid is a saturated fat found in foods that lead to obesity, cardiovascular disease, and Type II diabetes. It is linked to the development of resistance to insulin stimulation in muscle, liver and other organs involved in glucose metabolism, which, in turn, underlines the onset of Type II diabetes. The cellular and molecular mechanisms of this insulin resistance are complex and not completely understood. This article is focused on the role of palmitic acid as a precursor in the synthesis of sphingolipids, a class of lipid molecules that participate in cellular stress response. Recent evidence had indicated that increased dietary supply of palmitate can stimulate the rate of sphingolipid synthesis in “lean” tissues and generate excessive amounts of sphingolipid metabolites that have a negative effect on the insulin signaling cascade. Many experimental results point to the existence of a causative link between sphingolipid synthesis, insulin response, and hyperglycemia. It is not yet clear, however whether ceramides or glycosphingolipids are involved as both have been implicated to be inhibitors of the insulin signaling cascade. Evidence for a coordinated regulation of sphingolipid and tri/diacylglycerol metabolism complicates further the delineation of a single mechanism of sphingolipid effect on glucose homeostasis.
Effects of contrast media on endothelial cell monolayers under controlled flow conditions.

Abstract To compare the biocompatibility of nonionic and ionic intravascular contrast media in a more physiologic in vitro system, key aspects of blood flow through a microvessel were simulated. Toward this end, monolayers of endothelial cells placed in a specially designed flow chamber, real-time imaging of the monolayers by brightfield and phase videomicroscopy, and real-time imaging and computer-aided quantitation at normal hematocrit levels of platelet adhesion/aggregation to sites of monolayer injury by means of epifluorescence videomicroscopy were used. At a concentration in culture medium of 20% by volume, it was found that monolayer morphology was least altered by iohexol when compared with diatrizoate and ioxaglate; monolayer production of prostacyclin was enhanced (p ioxaglate > iohexol.
The microwave spectrum and nature of the subsurface of Mars

Expected microwave spectra of Mars are computed using an improved thermal model and accurate aspect geometry. It is found that when seasonal polar cap effects are included in the calculations, the observable spectrum of Mars is flat from 0.1-21 cm to within the accuracy of present data. The spectra obtained from this model are consistent with all the data and are obtainable from a relatively simple model (homogeneous, dry, smooth dielectric sphere). This result differs from that predicted by the analytical theory in common use which is in apparent conflict with the observed spectra. A range of electrical loss tangents, covering the extreme limits for likely dry particulate geological materials, is employed. The case of a lunar-like subsurface is completely consistent with all present data.
Technical notes on a theory of simplicity

Recently Samuel Richmond, generalizing Nelson Goodman, has proposed a measure of the simplicity of a theory that takes into account not only the polymorphicity of its models but also their internal homogeneity. By this measure a theory is simple if small subsets of its models exhibit only a few distinct (i.e., non-isomorphic) structures. Richmond shows that his measure, unlike that given by Goodman's theory of simplicity of predicates, orders the order relations in an intuitively satisfactory manner. In this note I formalize his presentation and suggest an improvement designed to overcome certain technical difficulties.
Bassogigas profundissimus (Roule) 1913 (Pisces: Brotulidae) from the North Pacific Ocean

Abstract Two specimens of Bassogigas profundissimus (Pisces: Brotulidae) are reported from Tufts Abyssal Plain in the North Pacific Ocean. These specimens are the first from the Pacific Ocean, the largest known (one 302 mm SL, the other ca. 230 mm SL), and the shallowest (5180 m) captured. Allometric growth in head length, horizontal eye diameter, and dorsal, anal, and pectoral fin lengths is evident. The swimbladder of each fish is contained in a tough, inelastic capsule.
The effects of the neodymium laser on meniscal repair in the avascular zone of the meniscus

Summary Thirty mature New Zealand white rabbits were divided into four surgical groups, and a 3- to 4-mm incision was made in the inner avascular zone of the central third of the medial meniscus. In group I, the tear was not treated by lasering or suturing. In group II, the tear was sutured. Group III was given four different doses of the neodymium: yttrium-aluminum-garnet (Nd:YAG) laser irradiation with no suturing. Group IV underwent meniscal suturing followed by the same four different laser irradiation doses. The animals were killed at 2, 4, and 6 weeks, with gross and histologic evaluation of the healing responses by group and time. The overall results showed no healing of this meniscal tear in the avascular zone. Suturing generally showed increased cellular infiltration. The varying doses of the Nd:YAG lasing demonstrated no gradient effect, and no "welding" of menisci was noted. The maximum cellular inflammatory response was noted in the sutured and lased menisci, reinforcing the importance of a stable meniscal environment for healing meniscal tears.
Quantum Size Effects in the Growth, Coarsening, and Properties of Ultra-thin Metal Films and Related Nanostructures

This review addresses the quantum mechanical nature of the formation and stability of ultrathin metal films. The competition between quantum confinement, charge spilling effects, and Friedel oscillations determines whether an atomically smooth metal film will be marginally, critically, or magically stable or totally unstable against roughening. Pb(111) films represent a special case, not only because of strong quantum oscillations in the stability of two-dimensional thin films but also because of the exceptionally fast coarsening of Pb nanoclusters. The latter appears to be due to the combined effects of size quantization and the existence of a unique mass exchange medium in the form of an unusually dense and highly dynamic wetting layer. The consequences of size quantization on the physical and chemical properties of the films are profound, some of which will be highlighted in this review.
Gibberellin Content of Immature Apple Seeds from Paclobutrazol-Treated Trees over Three Seasons

Seeds from heavily fruiting (“on-year”), mature untreated, and paclobutrazol-treated apple trees (Malus domestica Borkh. cv. Spartan) were sampled in mid-June 1987, mid-July 1987, and mid-July 1990. After seeds were freeze-dried, gibberellins (GAs) were extracted, purified, and fractionated via C18 reversed-phase high-performance liquid chromatography (HPLC). Nine GAs (GA1, GA3, GA4, GA7, GA8, GA9, GA19, GA20, and GA53) were quantified by the use of deuterated GA internal standards. Paclobutrazol trunk drench treatments reduced vegetative shoot elongation in the seasons that seeds were sampled by 55% or more. Between June 17, 1987 and July 15, 1987, the dry weight of seeds from both untreated and treated trees increased about 2.5 times and there were reductions, on a per seed basis, of GA4 in seeds from both untreated and treated trees, of GA7 in seeds from treated trees, and of GA9 in seeds from untreated trees. However, GA9 increased in seeds from treated trees. Changes in levels of some of the early-13-hydroxylation pathway GAs (GA15 GA3, GA8, GA19, GA20, and GA53) also occurred during the month. For mid-July harvested seeds, the pattern, with some exceptions, was that 2 years after paclobutrazol treatment (1987), levels of early-13-hydroxylation pathway GAs in seeds from treated trees were lower compared to controls but after 5 years (1990) their levels tended to increase. For the non-13-hydroxylated GAs (GA4, GA7, and GA9), 2 years after paclobutrazol treatment, GA4 levels were equal in seeds from untreated and treated trees, GA7 decreased in seeds from treated trees compared with controls, but GA9 levels increased. Levels of these three GAs were higher in seeds from treated trees 5 years after treatment (1990) but levels of GA4, GA7, and GA9 dramatically increased in seeds from treated trees 4 years after treatment (1989), as we previously reported.
"Cold bone scans" as a sign of hemorrhagic infarcts of the spine in Gaucher's disease.

The most common form of Gaucher's disease, type 1 (chronic non-neuronopathic), results in accumulation of glucocerebroside in reticuloendothelial cells of the spleen, liver and bone marrow, with frequent occurrence of bone pain due to vaso-occlusive crisis. We report the finding of a “cold” vertebral body on bone scan in two patients with Gaucher's disease and bone crisis. Photopenia was so striking as to give the appearance of a “missing” vertebra. Concurrent plain films appeared normal. In one patient Gaucher's disease had not previously been diagnosed.
Understanding SDO/AIA Observations of the 2010 June 13 EUV Wave Event: Direct Insight from a Global Thermodynamic MHD Simulation

In this work, we present a comprehensive observation and modeling analysis of the 2010 June 13 extreme-ultraviolet (EUV) wave observed by the Atmospheric Imaging Assembly (AIA) aboard the Solar Dynamics Observatory (SDO). Due to extreme advances in cadence, resolution, and bandpass coverage in the EUV regime, the AIA instrument offers an unprecedented ability to observe the dynamics of large-scale coronal wave-like transients known as EUV waves. To provide a physical analysis and further complement observational insight, we conduct a three-dimensional, time-dependent thermodynamic MHD simulation of the eruption and associated EUV wave, and employ forward modeling of EUV observables to compare the results directly observations. We focus on two main aspects: (1) the interpretation of the stark thermodynamic signatures in the multi-filter AIA data within the propagating EUV wave front, and (2) an in-depth analysis of the simulation results and their implication with respect to EUV wave theories. Multiple aspects, including the relative phases of perturbed variables, suggest that the outer, propagating component of the EUV transient exhibits the behavior of a fast-mode wave. We also find that this component becomes decoupled from the evolving structures associated with the coronal mass ejection that are also visible, providing a clear distinction between wave and non-wave mechanisms at play.
Guidelines for implementing a guidance/counseling program for gifted and talented students

The purpose of this article is to delineate the components of a comprehensive guidance/counseling plan that should develop from the regular school program at all grade levels. These suggestions apply to all staff, family, and community members involved in the guidance process. In particular, this plan emphasizes the importance of the program reflecting the specific needs most prevalent among the gifted and the specific problems that may result from neglected needs.
Differential Effects of HIF-1 Inhibition by YC-1 on the Overall Outcome and Blood-Brain Barrier Damage in a Rat Model of Ischemic Stroke

Hypoxia-inducible factor 1 (HIF-1) is a master regulator of cellular adaptation to hypoxia and has been suggested as a potent therapeutic target in cerebral ischemia. Here we show in an ischemic stroke model of rats that inhibiting HIF-1 and its downstream genes by 3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole (YC-1) significantly increases mortality and enlarges infarct volume evaluated by MRI and histological staining. Interestingly, the HIF-1 inhibition remarkably ameliorates ischemia-induced blood-brain barrier (BBB) disruption determined by Evans blue leakage although it does not affect brain edema. The result demonstrates that HIF-1 inhibition has differential effects on ischemic outcomes and BBB permeability. It indicates that HIF-1 may have different functions in different brain cells. Further analyses show that ischemia upregulates HIF-1 and its downstream genes erythropoietin (EPO), vascular endothelial growth factor (VEGF), and glucose transporter (Glut) in neurons and brain endothelial cells and that YC-1 inhibits their expression. We postulate that HIF-1-induced VEGF increases BBB permeability while certain other proteins coded by HIF-1's downstream genes such as epo and glut provide neuroprotection in an ischemic brain. The results indicate that YC-1 lacks the potential as a cerebral ischemic treatment although it confers certain protection to the cerebral vascular system.
The Characterization of Ice Hydrometeor Gamma Size Distributions as Volumes in N0–λ–μ Phase Space: Implications for Microphysical Process Modeling

AbstractGamma distributions represent particle size distributions (SDs) in mesoscale and cloud-resolving models that predict one, two, or three moments of hydrometeor species. They are characterized by intercept (N0), slope (λ), and shape (μ) parameters prognosed by such schemes or diagnosed based on fits to SDs measured in situ in clouds. Here, ice crystal SDs acquired in arctic cirrus during the Indirect and Semi-Direct Aerosol Campaign (ISDAC) and in hurricanes during the National Aeronautic and Space Administration (NASA) African Monsoon Multidisciplinary Analyses (NAMMA) are fit to gamma distributions using multiple algorithms. It is shown that N0, λ, and μ are not independent parameters but rather exhibit mutual dependence. Although N0, λ, and μ are not highly dependent on choice of fitting routine, they are sensitive to the tolerance permitted by fitting algorithms, meaning a three-dimensional volume in N0–λ–μ phase space is required to represent a single SD. Depending on the uncertainty in the mea...
Cytomegalovirus induces T-cell independent apoptosis in brain during immunodeficiency

Abstract Background: Cytomegalovirus (CMV) is the most common opportunistic viral pathogen associated with HIV/AIDS or immunosuppressive therapy. Systemic pathology may be caused either through direct virus-mediated infection or by indirect mechanisms such as ‘by-stander’ apoptosis. CMV infection of the central nervous system (CNS) occurs late in disease progression and understanding of pathology in the brain is fundamental for selection of appropriate therapies. Objectives: Using a model of disseminated neurotropic CMV disease, these experiments are designed to identify cellular predilection of murine CMV (MCMV) within mature brain and to determine, if CMV induces apoptosis within CNS cells. Study design: Adult immunodeficient (SCID) and normal BALB/c mice were infected via the tail vein with 4.5 × 105 pfu recombinant MCMV expressing a green fluorescent protein reporter. Animals were perfused at various time periods from 3 to 35 days post inoculation and tissues were stained for MCMV, GFAP, NEU-N, MBP, TUNEL, and caspase-3. Results: CMV infection within brain was observed in multiple, independent foci affecting several different cell types, including neurons, glial cells, meninges, ependymal cells, and cerebral vessels. Cellular changes included nuclear karyopyknosis and karyorrhexis, and associated meningitis, choroiditis, encephalitis, vasculitis, and necrosis. TUNEL and caspase-3 staining of brain-demonstrated apoptosis of nearby ‘by-stander’ meningial, glial, and neuronal cells, but only in immunodeficient mice lacking T- and B-lymphocytes. Generally, only large CMV infection foci were associated with apoptosis of non-infected adjacent cells. Conclusions: These results indicate that MCMV may cause both direct and indirect pathology to brain and that T-cell independent apoptosis of surrounding cells of the CNS may be an important mechanism of disease in the pathogenesis of neurotropic CMV.
Relationship of sensitization-repression dimension to daydream behavior types.

To test the hypothesis of a positive association between sensitization-repression scale score and frequency types of daydream behavior, 101 women and 105 men were administered a daydream-frequency ...
Responding to surrogate requests that seem inconsistent with a patient's living will.

Abstract Clinicians may feel conflicted when a patient's legal decision maker is making decisions that seem inconsistent with a patient's living will. We provide evidence-based information to help clinicians consider whether a surrogate's inconsistent decisions are ethically appropriate. Surrogates are not flawless translators of their loved one's preferences; they are influenced by their own hopes and the current clinical context. Patients may be aware of this, are often concerned about burdening their loved ones, and often grant their surrogates leeway in interpreting their wishes. When appropriate, clinicians should respect surrogates' interpretations of patient values and take steps to decrease surrogate stress during the decision-making process. Finally, if clinicians are cognizant of their own values and preferences, they may recognize how these may affect their responses to certain clinical cases.
A technique for measuring the perception of added resistive loads during nasal breathing

Abstract The perception of resistive loads added to nasal breathing was assessed in ten healthy adults using established psychophysical methods previously described for oral breathing. Detection threshold, that is, the smallest incremental resistance that the subject could detect 50% of the time, was determined at three different time periods (0, 30, and 60 min) on two separate days to determine the reproducibility of values over time. Nasal airway resistance measurements were made before and after threshold determinations to determine the influence of baseline resistance on the ability to detect added loads as well as to assess any effects of the procedure itself on resting nasal airway resistance. Analyses of the data revealed that subject-to-subject differences were the largest source of variability in threshold values followed by time period-to-time period differences and day-to-day variability. Although it was the smallest variability source, day-to-day variability still was significantly greater than zero. In contrast to previously published resports on resistive load detection during mouth breathing, the degree of baseline resistance did not appear to influence the subject's ability to detect added resistive loads during nasal breathing. These techniques may provide a methodological basis for objectively evaluating the effects of pharmacologie agents on perceived nasal patency.
Parasitic-aware design and optimisation of RF power amplifiers

Design considerations using parasitic-aware synthesis and optimisation techniques are presented for a three-stage 30 dBm 900 MHz class-E power amplifier implemented in a 0.35 μm standard digital CMOS process. Using both bond wire and on-chip square spiral inductors, the PA achieves 49% drain efficiency η and 25 dB power gain using a single 3.3 V power supply. Experience shows that the class-E PA design space is complex with many local minima. Thus, simulated annealing optimisation is chosen because of its inherent hill climbing ability that allows it to avoid being trapped in sub-optimum local minima. The paper first demonstrates the severe effects of parasitics by comparing results of switching power amplifier designs with both parasitic-free and parasitic-laden on-chip inductors. The results of parasitic-aware synthesis are then presented, including an illustration of its potential for power amplifier topology selection.
Three-dimensional estimates of the coronal electron density at times of extreme solar activity

[1] This paper presents quantitative three-dimensional (3-D) reconstructions of the electron density (Ne) in the solar corona between 1.14 and 2.7 solar radii (R⊙) formed from polarized brightness (pB) measurements made by the Mauna Loa Solar Observatory Mark-IV (Mk4) K-coronameter at the time of the extreme solar events of October and November 2003. The 3-D reconstructions are made by a process called solar rotational tomography that exploits the view angles provided by solar rotation during a 2-week period. Although this method is incapable of resolving dynamic evolution on timescales of less than about 2 weeks, a qualitative comparison of the reconstructions to instantaneous Extreme ultraviolet Imaging Telescope images (EIT) shows good agreement between coronal holes, active regions, and “quiet Sun” structures on the disk and their counterparts in the corona at 1.2 R⊙.
The fine structure of developing unit collagenous fibrils in the chick.

Perivertebral cervical connective tissue was taken from chick embryos of incubation ages from 72 hours through hatching and from 4, 8, 12, and 16 week old chicks. Preparations for electron microscopy were routine except for en bloc staining with 5% aqueous uranyl acetate. Collagenase digestions of thin sections confirmed the presence of tropocollagen in banded extracellular fibrils. Banding becomes demonstrable in fibrils at about seven days but repeating units cannot be measured. Close to connective tissue cells the banded material is present in wide sheets. Partially banded fibrils (250 A wide) physically related to microfibrils are present in acellular regions. Growth in fibril diameter is slow through the second week (up to 300 A) but increases nearly 200 A on days 14 and 15. Fibrils larger than 500 A resist uranium and lead staining following the period of accelerated growth. Smaller fibrils (< 500 A) continue to stain well. A basic banding pattern of measurable periodicity is established by the eighth day. This consists of a major doublet, two minor doublets, and two singlets. The intraperiod distance does not change significantly with growth (510 A average). Additional bands near the first minor doublet and singlets of the basic pattern are first clearly demonstrable at 14 and 15 days. Ambiguities in banding and period length are believed to be due to plane of section, interference with detail by other fibrils and flaky amorphous material or possibly to differential shrinkage along the length of a single fibril.
The genomic synteny at DNA level between human and chimpanzee chromosomes

The evolutionary relationship between human (Homo sapiens) and chimpanzee (Pan troglodytes) has been the subject of debate and scrutiny for over two decades. The close relationship established by numerous parameters may or may not reflect homology at the DNA level. The recent advent of a molecular method termed the chromosomein situ suppression hybridization (CISS)-technique has prompted us to explore the phylogenetic relationship at the DNA sequence level. Cross-hybridization data using human-derived whole chromosome paints (WCPs) suggests an apparent genomic synteny with chimpanzee chromosomes at the DNA level, thus providing a better understanding of an evolutionary relationship between humans and chimpanzees.
Towards a unified framework for interval based qualitative computational matrix structural analysis

Abstract Qualitative reasoning about physical system behavior is one of the things engineers do to assess the “reasonableness” of the outputs from their numerical simulations, but such reasoning is typically assumed to be an exclusively human activity under the rubric of “engineering judgement”. It is the authors' contention that such reasoning can be rendered in a computational manner and that Interval Analysis (IA) provides the mathematical foundations to do so. Using Interval Analysis, the notion of operations with numbers is replaced with operations on sets of numbers. Representation of structural parameters with sets of known values permits a simultaneous parametric study. Using concepts from Qualitative and Order of Magnitude Reasoning, interval methods are augmented to perform levels of both qualitative and quantitative mechanical reasoning. Whereby interval techniques employ tight numerical intervals, it is possible to use large or even infinite intervals in order to apply qualitative computational techniques. A logic based implementation facilitated prototyping as well as approaching the unification of the various forms of analysis. Examples discussed in this paper will demonstrate that such a link between qualitative and quantitative techniques exists within a framework of interval analysis.
Evidence for the presence of precursor B cells in normal and in hormonally bursectomized chick embryos.

Abstract Embryonic bone marrow of normal and hormonally bursectomized chicks was examined for the presence of hematopoietic precursor cells capable of migrating to the thymus and bursa and of differentiating into functional T and B cells, respectively. Following transfer of chromosomally marked bone marrow of normal and in ovo bursectomized 14-day-old embryos to 14-day-old γ-irradiated embryonic recipients, donor cells proliferated in the marrow, thymus, and bursa of recipients, and differentiated to PHA- and Con A-responsive T cells as well as to dextran sulfate- and anti-immunoglobulin-responsive B cells. In contrast, when marrow of 2-day-old hatched normal and in ovo-bursectomized donors was transferred to 14-day-old embryonic recipients, donor cells repopulated only the marrow and thymus of recipients which was followed by differentiation to Con A- or PHA-responsive T cells, but the same donor cells failed to proliferate in the bursa and there was no differentiation to functional B cells of donor type. The data were fitted to a model of T- and B-cell differentiation from the stem cell level and they suggest the presence of separate populations of committed precursor T (PT) and precursor B (PB) cells in the marrow of normal and in ovo bursectomized embryos with a bursa-independent selective disappearance of PB cells from the marrow during the late embryonic period.
Studies on fermentation aeration: II. Catalyst effects on sulphite oxidation rates

Sulphite oxidation rates using several metal ions as catalyst in four types of contacting equipment have been measured over a considerable range of agitation levels. The data show no simple relation between the various sulphite oxidation rates and the transfer coefficient for oxygen from air to fermentation media. On a mesure les taux d'oxydation de sulfites a des niveaux d'agitation tres varies, en utilisant plusieurs ions metalliques comme catalyseurs, dans quatre types de contacteurs. Les resultats ne permettent pas d'etablir une relation simple entre les differents taux d'oxydation des sulfites et le coefficient de transfert pour l'oxygene, de l'air au milieu de fermentation.
Nickel-Based Superalloys for Advanced Turbine Engines: Chemistry, Microstructure and Properties

The chemical, physical, and mechanical characteristics of nickel-based superalloys are reviewed with emphasis on the use of this class of materials within turbine engines. The role of major and minor alloying additions in multicomponent commercial cast and wrought superalloys is discussed. Microstructural stability and phases observed during processing and in subsequent elevated-temperature service are summarized. Processing paths and recent advances in processing are addressed. Mechanical properties and deformation mechanisms are reviewed, including tensile properties, creep, fatigue, and cyclic crack growth. I. Introduction N ICKEL-BASED superalloys are an unusual class of metallic materials with an exceptional combination of hightemperature strength, toughness, and resistance to degradation in corrosive or oxidizing environments. These materials are widely used in aircraft and power-generation turbines, rocket engines, and other challenging environments, including nuclear power and chemical processing plants. Intensive alloy and process development activities during the past few decades have resulted in alloys that can tolerate average temperatures of 1050 ◦ C with occasional excursions (or local hot spots near airfoil tips) to temperatures as high as 1200 ◦ C, 1 which is approximately 90% of the melting point of the material. The underlying aspects of microstructure and composition that result in these exceptional properties are briefly reviewed here. Major classes of superalloys that are utilized in gas-turbine engines and the corresponding processes for their production are outlined along with characteristic mechanical and physical properties.
EXERCISE, DEPRESSION, AND SELF-ESTEEM

In a sample of 90 college students, engaging in exercise was not associated with sadness/happiness or self-esteem.
Stress responses and disease in three wintering house finch (Carpodacus mexicanus) populations along a latitudinal gradient

In laboratory studies, stress hormones have been shown to impair immune functions, and increase susceptibility to diseases. However, the interactions between stress hormones and disease have rarely been studied in free-ranging populations. In this study, we measured concentrations of the avian stress hormone corticosterone across four winter months (December-March) over two years in three eastern North American house finch populations (Carpodacus mexicanus) along a latitudinal gradient. Because Mycoplasma gallisepticum infections appear in these populations in late winter, we hypothesized that the timing of the disease outbreaks could be mediated by changes in corticosterone concentrations. We found a significant increase in baseline and stress-induced plasma corticosterone concentrations in house finches without Mycoplasma symptoms in late winter; when the prevalence of Mycoplasma infection peaks. We also found that house finches with Mycoplasma symptoms had elevated stress-induced corticosterone concentrations. High baseline concentrations were associated with a low body condition and a high fat load. We found that the relationship between corticosterone concentrations and the latitude of the study population changed between years. The first year, corticosterone concentrations were lowest in the southern latitude, but became higher in the second year when average winter temperatures were low. A causal understanding of the implications for this variation in corticosterone concentrations for Mycoplasma disease dynamics awaits further studies.
Organic diets and children's health.

In their article “Organic Diets Significantly Lower Children’s Dietary Exposure to Organophosphorus Pesticides,” Lu et al. (2006) used language that is likely to be misused by organic food marketers to promote high-priced foods and could discourage lower-income parents from providing their children with a diet rich in fruits and vegetables.
DUAL COLUMN-DIFFERENTIAL FLAME IONIZATION DETECTOR SYSTEM AND ITS APPLICATION WITH PACKED AND GOLAY TYPE COLUMNS.

Abstract The influence of liquid phase bleeding on the analytical results and the possibilities for its compensation in programmed temperature for chromatography were discussed. A new differential FID was described; the dual columnn system incorporating this detector allows the use of both packed and open tubular (Golay) columns. The application of the system to a few problems was shown and its quantitative accuracy was demonstrated.
Some properties and crystal growth of Zn-substituted LiNbO3 solid solutions

A nonstoichiometric phase has been identified with the formula (Li1−xZnx/2)NbO3 (0 < x ≤ 0.25) and a LiNbO3 type structure. Cation vacancies occur at the Li-site, and the defect structure was still stable at high temperatures. The ferroelectric Curie temperature of LiNbO3 decreases linearly with the increase of x. The sigle crystals were grown by a floating zone method, and it was found that the c-axis grown crystals were poled without applying any external electric field.
Naphthyridine chemistry. XVI. A literature correction —The preparation of 2,4-Dimethyl-7-ethoxy-1,8-naphthyridine 1-Oxides

The N-oxidation of 2,4-dimethyl-7-ethoxy-1,8-naphthyridine has been shown to afford the 1-oxide rather than the 1,8-dioxide as reported by others.
Temperature-Mediated Stability of the Interaction Between Spider Mites and Predatory Mites in Orchards

The nonlinear behavior of the Holling-Tanner predatory-prey differential equation system, employed by R.M. May to illustrate the apparent robustness of Kolmogorov’s Theorem when applied to such exploitation systems, is re-examined by means of the numerical bifurcation code AUTO 86 with model parameters chosen appropriately for a temperature-dependent mite interaction on fruit trees. The most significant result of this analysis is that there exists a temperature range wherein multiple stable states can occur, in direct violation of May’s interpretation of this system’s satisfaction of Kolmogorov’s Theorem: namely, that linear stability predictions have global consequences. In particular these stable states consist of a focus (spiral point) and a limit cycle separated from each other in the phase plane by an unstable limit cycle, all of which are associated with the single community equilibrium point of the system. The ecological implications of such metastability, hysteresis, and threshold behavior for the occurrence of outbreaks, the persistence of oscillations, the resiliency of the system, and the biological control of mite populations are discussed.
A Communication Library Using Active Messages to Improve Performance of PVM

We present a communication library to improve performance of PVM. The new library introduces communication primitives based on Active Messages. We propose a hybrid scheme that includes a signal driven message notification scheme plus controlled polling. The new communication library is tested along with the normal PVM library to assess the improvement in performance.
Patient radiation doses in interventional cardiology in the U.S.: Advisory data sets and possible initial values for U.S. reference levels

Purpose: To determine patient radiation doses from interventional cardiology procedures in the U.S and to suggest possible initial values for U.S. benchmarks for patient radiation dose from selected interventional cardiology procedures [fluoroscopically guided diagnostic cardiac catheterization and percutaneous coronary intervention (PCI)]. Methods: Patient radiation dose metrics were derived from analysis of data from the 2008 to 2009 Nationwide Evaluation of X-ray Trends (NEXT) survey of cardiac catheterization. This analysis used deidentified data and did not require review by an IRB. Data from 171 facilities in 30 states were analyzed. The distributions (percentiles) of radiation dose metrics were determined for diagnostic cardiac catheterizations, PCI, and combined diagnostic and PCI procedures. Confidence intervals for these dose distributions were determined using bootstrap resampling. Results: Percentile distributions (advisory data sets) and possible preliminary U.S. reference levels (based on the 75th percentile of the dose distributions) are provided for cumulative air kerma at the reference point (Ka,r), cumulative air kerma-area product (PKA), fluoroscopy time, and number of cine runs. Dose distributions are sufficiently detailed to permit dose audits as described in National Council on Radiation Protection and Measurements Report No. 168. Fluoroscopy times are consistent with those observed in European studies, but PKA is higher in the U.S. Conclusions: Sufficient data exist to suggest possible initial benchmarks for patient radiation dose for certain interventional cardiology procedures in the U.S. Our data suggest that patient radiation dose in these procedures is not optimized in U.S. practice.
Average boundary conditions in Cauchy problems

We consider the general Cauchy problem with initial data in a Hilbert space and with a formal dissipative linear generator. A complete parametrization is known of the (abstract) boundary conditions which make this problem well set. We exhibit a distinguished subset BE of the set B of boundary conditions and demonstrate explicitly that the evolution associated with each B in B can be represented as a (time independent) average over the evolutions associated with B′ in BE. Applications are discussed to Schrodinger equations in bounded regions or with singular potentials.
ErbB-4 s80 intracellular domain abrogates ETO2-dependent transcriptional repression.

ErbB-4 is cleaved by α- and γ-secretases to release a soluble 80-kDa intracellular domain, termed s80, which translocates to the nucleus. s80 is present in the nucleus of normal and cancerous mammary cells and is predicted to have a role in cell differentiation. To further investigate the mechanism by which s80 may mediate differentiation, we tested whether s80 regulates Eto2, a transcriptional corepressor that is involved in erythrocyte differentiation and is also implicated in human breast cancer. Here we show that ligand binding to ErbB-4 causes s80 translocation to the nucleus, where it colocalizes and interacts with Eto2. Expression of s80 blocks Eto2-mediated transcriptional repression of a heterologous promoter. This effect on Eto2 does not require s80 kinase activity and is mediated by the carboxyl-terminal region of s80. Although other cell surface receptors regulate transcription by activating signal transduction cascades, these data present a novel mechanism of corepressor regulation and suggest a role for Eto2 in ErbB-4-dependent differentiation.
Quasi‐rational expectations: Experimental evidence

The theory of quasi-rational expectations was tested under the controlled conditions of the economics laboratory. Five experiments were conducted with a variety of stochastic processes. In each experiment, subjects produced one-step-ahead forecasts of the variable generated by a Monte Carlo process. Comparisons of the performance of an aggregate of subjects' forecasts versus an ARIMA model showed that for relatively simple series (such as those generated by autoregressive processes of first or second order) the aggregate forecast was indistinguishable from that of the model. These results lend support to the theory that forecasts from an ARIMA model can serve as substitutes for aggregate expectations in macroeconomic policy models under some conditions.
Unenhanced helical computed tomography for suspected urinary tract stones: Current state of the art

In an increasing number of hospitals, unenhanced helical computed tomography (CT) has replaced intravenous urography in the evaluation of patients with suspected ureterolithiasis. CT is safe and efficient, and it provides a wealth of diagnostic information including the size, number, and location of stones, the effects of stones on the urinary tract, and alternative diagnoses in patients without stone disease. CT is significantly faster than urography and does not generally require placement of an intravenous line or injection of contrast agent, and consequently there is no risk of contrast reaction. The use of unenhanced helical CT for suspected ureterolithiasis requires careful attention to detail and familiarity with urinary tract anatomy and signs of urinary tract obstruction.
Biochemical characterization of ethanol actions on dihydropyridine-sensitive calcium channels in brain synaptosomes

Abstract This study was undertaken to investigate the biochemical events underlying the inhibitory action of ethanol on dihydropyridine-sensitive voltage-dependent Ca 2+ channels in brain synaptosomes. The binding of radiolabeled dihydropyridine was used to determine functional Ca 2+ channels in synaptosomes following exposure to ethanol. No effect on [ 3 H]PN 200-110 binding was found when disrupted synaptosomal membranes were incubated with ethanol concentrations as high as 300 mM, suggesting that ethanol did not interact directly with sites on or near the Ca 2+ channels. However, when intact synaptosomes were first incubated with ethanol (100 mM) at 37 ° and then disrupted, a significant reduction in membrane binding of [ 3 H]PN 200-110 was found. Ethanol incubation of synaptosomes at 0 ° was ineffective. It appears that metabolic processes involving intracellular factors were required in the ethanol action. In examining this possibility, [ 3 H]PN 200-110 binding was activated by incubation of disrupted membranes with MgATP and Ca 2+ -calmodulin, and ethanol was found to inhibit the activation in a concentration-dependent manner (50–200 mM). [ 3 H]PN 200-110 binding to membranes was also activated by incubation with MgATP and cyclic AMP-dependent protein kinase, but this activation was not inhibited by ethanol. These findings are consistent with the interpretation that ethanol acts on Ca 2+ channels by inhibiting calmodulin-dependent activation of the channels.