cssi/SciSciGPT-SciSciNet huggingface dataset:
Regulation of polysome aggregation in a cell-free system through ammo acid supply☆☆☆

Rat-liver polysemes were incubated with an energy-generating system and with activating and transfer enzyme preparations depleted of free amino acids. When no amino acids were added to the reaction mixture, this system incorporated [14C]leucine to a limited extent, and attained a plateau within 20 minutes. In the presence of a complete mixture of amino acids, incorporation was more extensive, and continued at a diminishing rate up to 60 minutes. Under both conditions of amino acid supply, extensive and rapid breakdown of polysomes to monosomes and other oligosomes occurred. However, in the presence of added amino acids there was a greater accumulation of free ribosomes, as shown by reaction with polyuridylic acid. It is concluded that the system finally ceases to incorporate in the presence of an adequate supply of amino acids due to the lack of some chain-initiating factor required for the interaction of free ribosomes with messenger RNA. When the system without added amino acids ceased to incorporate the [14C]amino acid, it could be restarted by adding a complete mixture of amino acids, but not by adding a mixture lacking any one of the following: arginine, histidine, cysteine, lysine, methionine, phenylalanine, threonine, tryptophan or valine. Polysome aggregates were restored simultaneoulsy with amino acid incorporation; this was accompanied by a reduction in monosomes and other oligosomes with preferential removal of free ribosomes. The resynthesis of polysomes did not occur when mixtures lacking any one of the above named amino acids were added to the incubation. Resynthesis of polysomes could also be prevented by adding ribonuclease (2 μg/ml.), cycloheximide (1 mg/ml.), or puromycin (200 μg/ml.) to the incubation mixture simultaneously with the addition of the amino acids. It is concluded that amino acid supply is one factor regulating attachment of free ribosomes to messenger RMA, and that conditions compatible with peptide synthesis must be provided in order to obtain polysomes.
The mechanism for increased protein synthesis during Xenopus oocyte maturation.

Abstract The translational efficiency of Xenopus oocytes before and after the induction of maturation was determined. Polysomes from control and mature oocytes sedimented in a sucrose gradient with a peak value of 300 S, which corresponds to a weight-average packing density of 10 ribosomes per mRNA. The level of radioactivity associated with nascent chains approximately doubled in mature oocytes relative to controls. While, in certain instances, the ribosome transit times of injected heterologous mRNAs did decrease during maturation, the transit times of endogenous mRNAs did not change. Taken together, the data indicate that the twofold increase in protein synthesis which occurs during Xenopus oocyte maturation ( W. J. Wasserman, J. D. Richter, and L. D. Smith, 1982 , Develop. Biol. 89, 152–158) is due primarily to a recruitment of mRNA rather than a change in translational efficiency.
Design and Use of Microphone Directional Arrays for Aeroacoustic Measurements

An overview of the development of two microphone directional arrays for aeroacoustic testing is presented. These arrays were specifically developed to measure airframe noise in the NASA Langley Quiet Flow Facility. A large aperture directional array using 35 flush-mounted microphones was constructed to obtain high resolution noise localization maps around airframe models. Complementing the large array is a small aperture directional array, constructed to obtain spectra and directivity information from regions on the model. Both arrays are employed in acoustic measurements of a 6 percent of full scale airframe model consisting of a main element NACA wing section with a 30 percent chord half-span flap. Representative data obtained from these measurements are presented, along with details of the array calibration and data post- processing procedures.
The role of frontier molecular orbital ordering on electronic communication in porphyrin arrays

Abstract Electronic donor–acceptor communication in porphyrin-based molecular electronics is addressed theoretically. The order of the a 1u and a 2u frontier occupied orbitals has been proposed by others to affect excited energy transfer. We examined the effects of the nature and pattern of substituents upon analog monomer porphyrin orbitals using DFT (B3LYP/6-31G(d,p)) and the four-orbital model of porphyrin electronic structure. The excited state energy transfer rate was found to be very sensitive to these orbitals' contributions to porphyrin uv/visible absorptions (B- and Q-band). Ground state homodimer calculations validated the monomer results.
Photorefractive damage in whispering gallery resonators

We report on a study of optical properties of whispering gallery mode resonators made out of as-grown nominally pure lithium niobate crystals. We have observed a surprising dynamic modification of the spectrum of the resonators illuminated with the near infrared light. We attribute this effect to the photorefractive damage of the resonator host material.
Crossing the Hopf Bifurcation in a Live Predator-Prey System

Population biologists have long been interested in the oscillations in population size displayed by many organisms in the field and laboratory. A wide range of deterministic mathematical models predict that these fluctuations can be generated internally by nonlinear interactions among species and, if correct, would provide important insights for understanding and predicting the dynamics of interacting populations. We studied the dynamical behavior of a two-species aquatic laboratory community encompassing the interactions between a demographically structured herbivore population, a primary producer, and a mineral resource, yet still amenable to description and parameterization using a mathematical model. The qualitative dynamical behavior of our experimental system, that is, cycles, equilibria, and extinction, is highly predictable by a simple nonlinear model.
Diversity, law and justice: a Deleuzian semiotic view of ‘criminal justice’

This article takes a Deleuzian view toward diversity, law and justice. It makes use of the insights developed in his two books on cinema comparing an “organic regime” to a “crystalline regime.” The former will be seen as the image of thought and regime of signs of traditional criminal justice practices (due process model, crime control model, family model, actuarial justice, restorative justice); the latter, the basis of a transformative justice (social justice) and the regime of signs that are its constitutive elements. Deleuze’s views on semiotics can be fruitfully contrasted with Lacan’s. I want to indicate how Jacques Lacan’s psychoanalytic semiotics, on the descriptive level, quite accurately describes the connection of desire based on lack with capital logic, whereas, Deleuze provides an alternative ontology (desire based on production) and develops suggestions for privileging a becoming rather than a being. His is a call for ongoing transformations. I want to indicate how diversity, transformation and tolerance can have better developments in a Deleuzian model of the crystalline regime. This entails alternative discursive subject positions and regimes of signs within which constructions of reality by diverse peoples find wider expression. Accordingly, this is about better approximations to social justice.
Central neuroendocrine regulation of renin secretion rate: a hypothesis

A literature survey is presented from which is proposed a kidney-anterior hypothalamic endocrine feedback loop may be involved in regulation of renin secretion.
COMPARISON OF GEOMAGNETIC STORMS AND TROUGH DEVELOPMENT AT SOLAR-ACTIVITY MAXIMUM AND MINIMUM.

Abstract Geomagnetic storms have long been found to be related to solar storms. However, the effects of solar activity within the lower atmosphere have been postulated but not as yet confirmed. A positive correlation was found between trough development at 300 mb and geomagnetic storms during the 1956–1957 solar activity maxima in a study performed at the High Altitude Observatory of the University of Colorado. Similar studies performed at the Army Ballistic Missile Agency and at Florida Institute of Technology have also shown positive correlations between geomagnetic storms and subsequent trough development. A comparison of the results of these investigations into a possible solar weather effect are presented.
Reinforcement Analysis of a Slab Tank

The objective of this paper is to reduce the stresses and deflection of an existing slab tank [2]. The slab tank is to store various criticality liquids used in today’s industry. The preliminary overall dimensions of the slab tank are determined from the capacity of the stored liquids. The slab tank design is broken up into (a) two long side members, (b) two short side members, (c) top head, and (d) bottom head. The slab tank is supported from the bottom at a height by a rectangular plate enclosure. The deflection of the linear space is a critical requirement. The deflection is controlled by providing external supports from the bottom at a height by adjustable bolts. The analysis of the slab tank showed excessive stresses at the concentrated supports. The slab tank was modified by providing reinforcement on the long side members. Several reinforcement arrangements were considered. The slab tank is subjected to two conditions. First, vacuum condition, the long side plates will deflect inwards. Second, internal pressure condition the design pressure consists of working internal pressure plus static head pressure. For this the long side plates will deflect outwards. The heads are designed for internal pressure at the bottom where the pressure is the maximum. The vacuum pressure is not critical. The dimensioned slab tank is modeled using STAAD III finite element software. The slab tank showed excessive stresses. The concentrated supports were removed. The long side member was reinforced by a Channel section. The slab tank analysis was simplified by modeling a single long side member and three cases of Channel section reinforcement were considered. The reinforced arrangement was analyzed by STAAD III finite element software. Further analysis by changing the Channel section by plate reinforcement was found to be better.Copyright © 2005 by ASME
An analogue of Hilbert's tenth problem for p-adic entire functions

Let p be a fixed prime integer, other than 2, Q p the field of p -adic numbers, and Ω p the completion of the algebraic closure of Q p . Let R p be the ring of entire functions in one variable t over Ω p ; that is, R p is the ring of functions f : Ω p → Q p such that f(t) is given by a power series around 0, of infinite radius of convergence: and where ∣ a ∣ p is the p -adic norm of a in Ω p . We prove: Theorem A. The positive existential theory of R p in the language L = {0, 1, t, +, ·} is undecidable . Theorem A gives a negative answer to the analogue of Hilbert's tenth problem for R p in the language L . Related results include those of [2] where it is shown that the first-order theory of entire functions on the complex plane is undecidable and the similar result for analytic functions on the open unit disk (this is due to Denef and Gromov, communicated to us by Cherlin and is as of now unpublished). It would be desirable to have a similar result in the language which, instead of the variable t , has a predicate for the transcendental (that is, nonconstant) elements of R p . A related problem is the similar problem for meromorphic functions on the real or p -adic plane or on the unit open or closed disk. These problems seem for the moment rather hard in view of the fact that the analogue of Hilbert's Tenth Problem for the field of rational functions over the complex numbers (or any algebraically closed field of characteristic zero) is an open problem.
Relationship between damage evolution and Si–H complexes formation in hydrogen implanted Si

Abstract The lattice damage and the chemical bonding in H implanted Si substrates with different doping levels were analyzed with Rutherford backscattering spectroscopy (RBS) in channeling mode and Infrared Spectroscopy (IR), respectively. We observed that the damage of room temperature implanted Si consisted of Si–H complexes and irradiation induced interstitial/vacancy pairs, and that the lattice damage decreased in the presence of pre-implanted boron. This reduction in lattice damage was most pronounced when B was not activated, regardless of Si substrate type.
Endovascular stenting for descending aneurysms: wave of the future or the emperor's new clothes?

for spearheading these exciting clinical investigations into novel endovascular therapies for aneurysm disease from within the specialty of cardiohoracic surgery. This provides the opportunity for these investigations to be imbued ith decades of collective wisdom from the perspective of cardiothoracic surg his also provides the opportunity for our specialty to continue leadership in the reatment of these diseases as technology advances. The article by Bavaria and colleagues 1 represents a large, multicenter compar ive trial between traditional aortic surgery and endografting for descending thoracic ortic aneurysms. The study is well conceived and well presented and demonstrates atisfactory early performance of the endografts. This is very important work, vital o the advancement of the field, for which the investigators are to be congratulated. It is extremely important to evaluate endograft therapy of aneurysms in organized linical trials. Ultimately, randomized trials of thoracic endografts versus open urgical repair will be required for strongly based conclusions to be drawn. It is important for medical science to evaluate endografting of aneurysms with nthusiasm for this new modality but, at the same time, with a grain of skepticism r at least realism. Multiple reasons to be cautious can be cited.
Research on Hydraulic Pitch-Control System of Wind Turbine

It is usually difficult to establish an accurate mathematical model for hydraulic servo system because of its complicated and non-linear properties. However, bond-graph method has its unique advantages in modeling such as processing multiple energy conversions. Furthermore, good results could be achieved by combining fuzzy control with normal PID control. As a result of air current load interfering with the system in changeable and complicated environment, process control is obviously important. Taking 1MW wind turbine pitch-control system as an example, a simulation research based on the above method is conducted.
Nuclear Structure of Na 22 . II. Some Gamma-Ray Doppler-Shift and Correlation Measurements

Levels of ${\mathrm{Na}}^{22}$ below an excitation energy of 4.4 MeV have been investigated through the ${\mathrm{F}}^{19}(\ensuremath{\alpha}, n\ensuremath{\gamma}){\mathrm{Na}}^{22}$ and ${\mathrm{Ne}}^{20}({\mathrm{He}}^{3}, p\ensuremath{\gamma}){\mathrm{Na}}^{22}$ reactions. Using the first reaction, initiated in a C${\mathrm{Cl}}_{2}$${\mathrm{F}}_{2}$ gas target, the Doppler shifts of $\ensuremath{\gamma}$-ray transitions from the 0.891-, 2.221-, and 2.572-MeV levels were measured using $\ensuremath{\alpha}$ energies between 4 and 7 MeV. From these results upper limits were placed on the lifetimes of the three initial states. Combining these upper limits with previously obtained lower limits yields the following restrictions on the mean lifetimes (in psec) for these three levels: $8l\ensuremath{\tau}l52$, $11l\ensuremath{\tau}l42$, and $10l\ensuremath{\tau}l42$, respectively. Proton-$\ensuremath{\gamma}$ angular correlations were measured at ${E}_{{\mathrm{He}}^{3}}=6.56$ MeV using the ${\mathrm{Ne}}^{20}({\mathrm{He}}^{3}, p\ensuremath{\gamma}){\mathrm{Na}}^{22}$ reaction. These results gave information on $\ensuremath{\gamma}$-ray branching and multipole-mixing ratios and served to limit the possible spin-parity assignments of some of the levels.
The Myofibrillar Complex and Fatigue: A Review

The basis for all biological movement is the conversion of chemical energy to mechanical energy by different classes of motor proteins. In skeletal muscle this motor protein is myosin II, a thick f...
Modelling Risers With Partial Strake Coverage

This paper compares model test data for risers with partial strake coverage to predictions made with the Vortex-Induced Vibration (VIV) prediction program SHEAR7 Versions 4.5 and 4.6. It is shown that new features in Version 4.6 substantially enhance the capability for predicting the VIV response of risers with partial coverage. Experimental data is taken from two large L/D tests: the NDP 38 m long riser tests and the Deepstar-Miami, 500 foot long riser. New methods are described for modeling risers partially covered with helical strakes. Key SHEAR7 parameters are recommended, based on parametric investigations to calibrate the model against the available experimental data. Recommended modeling procedures are described so as to facilitate implementation by SHEAR7 users in their VIV modeling tasks.Copyright © 2011 by ASME
Short-Term High Fat Feeding Increases Organ Injury and Mortality After Polymicrobial Sepsis

The purpose of this study was to examine the effect of short-term high fat feeding on the inflammatory response in polymicrobial sepsis. Male C57BL/6 mice at 6 weeks of age were randomized to a high-fat diet (HFD) (60% kcal fat) or control diet (CD) (16% kcal fat) for 3 weeks. After 3 weeks of feeding, sepsis was induced by cecal ligation and puncture (CLP) and animals were monitored for survival. In a separate experiment, after 3 weeks of feeding mice underwent CLP and were sacrificed at various time points thereafter. Tissue was collected for biochemical studies. Mice fed a HFD gained more weight and had a greater fat mass compared to CD-fed mice. Mice on a HFD had a lower probability of survival and more severe lung injury compared with CD-fed mice following sepsis. Myeloperoxidase (MPO) activity, an indicator of neutrophil infiltration, was increased in the lung and liver after CLP in HFD-fed mice compared with CD (P < 0.05). The plasma cytokines tumor necrosis factor-α (TNF-α) and interleukin (IL)-6 were increased in both groups after CLP, however, TNF-α and IL-6 levels were lower in HFD mice at 3 h after CLP compared with CD and consistent with lung, but not liver, messenger RNA (mRNA) expression. Leptin levels were higher in HFD-fed mice at 18 h after sepsis compared to baseline levels (P < 0.05). Polymicrobial sepsis increased hepatic nuclear factor-κB (NF-κB) activation in HFD-fed mice after CLP vs. CD-fed mice. Short duration high fat feeding increases mortality and organ injury following polymicrobial sepsis. These effects correspond to changes in NF-κB.
Associations between stress reactivity and sexual and nonsexual risk taking in young adult human males.

Abstract Release of the hormone cortisol represents a distress response to novel or stressful situations. Individual differences in such reactivity have been conceptualized as representing a relatively enduring, generalizable trait. In this study, cortisol responses to two experimentally manipulated “sexual” and “nonsexual” stressors were used to examine whether stress reactivity is related to sexual and nonsexual risk behavior in young adult males. Analyses were based on 150 males 18 to 25 years old; risk behavior was assessed in confidential, self-administered questionnaires. Analyses indicated that both stressors effectively elicited cortisol increases. Generalized reactivity, defined as a cortisol response to both stressors, was inversely associated with deviance (e.g., theft, substance use) and with two indicators of sexual risk taking (lifetime number of intercourse partners and frequency of condom use). Findings are discussed in terms of cross-situational consistency of stress responses, the utility of stress reactivity for understanding individual differences in risk taking, and the interpretive limitations imposed by study design.
Mechanisms influencing stimulus-response properties of the human corticospinal system

Abstract Background : Stimulus-response (S-R) properties of the corticospinal system in humans depend on the interactions that take place at different sites along the corticospinal pathway. The mechanisms influencing stimulus-response curves elicited by transcranial magnetic stimulation (TMS) and their operation site along the human neuraxis are poorly understood. In this study, we investigated the effects of CNS-active drugs with distinct mechanisms of action on S-R curves. Effects of each of these drugs on S-R curves would point to the involvement of specific mechanisms. Additionally, relative sensitivity of S-R curves compared with other measures of corticospinal excitability was studied. Methods : We studied the effects of lorazepam, which is a positive allosteric modulator of GABA A receptors; lamotrigine, an inhibitor of voltage-gated Na + and Ca 2+ channels; and d-amphetamine, an indirect agonist of the dopaminergic-adrenergic system on S-R curves, motor thresholds (MT), and intracortical inhibition (ICI) and facilitation (ICF) with a double-pulse technique. Maximum peripheral M responses and F waves were investigated as measures of the total α -motoneuron pool and its excitability. Results : F and M waves were unaffected by either the drugs or placebo. S-R curves were significantly depressed by lorazepam and lamotrigine without changes in ICI and ICF. Both S-R curves and ICF were enhanced by d-amphetamine. MT increased only with lamotrigine. Conclusions : S-R curves were influenced by changes in the GABAergic and monoaminergic system and Na + and Ca 2+ channel properties. Our results indicate that, out of different parameters of motor system excitability, S-R curves were the most sensitive.
Cost optimization in an FTTP environment

Verizon has developed several optimization methodologies for the design and operation of the FTTP network. Two of these methodologies, one design and one operations, will be presented and the benefits of advanced analytics discussed.
Effective-gluon model description of inclusive meson production in π +/- p and p p collisions

The recently introduced effective-gluon (EG) model is applied to inclusive meson production at large transverse momentum (p/sub t)/from ..pi../sup + -/p and pp interactions. In the EG model the dependence of the inclusive differential cross section on p/ sub t/ and center-of-momentum energy ..sqrt..s is characterized by a single universal constant B = 18 GeV/sup 2/; this constant is obtained by fitting to the inclusive data for pp ..-->.. cX with c = ..pi../sup + -/..pi../sup 0/, K/sup + -/p, and p-bar. Since the EG model requires that the inclusive differential cross sections for ..pi../sup + -/p ..-->.. X/should be characterized by the same constant B, the dependence of these cross sections on p/sub t/and ..sqrt..s should follow from the previous analysis of pp ..-->.. cX without the introduction of any additional parameters. The only new information required is the form of the momentum distribution function for partons in the incident pion. Several models for this function are considered and it it shown that all of the alternatives lead to approximately the same predictions. Comparison of theory and experiment indicates that the EG model description of the recent Fermilab data of Donaldson et al. is good to approximately 15--20 %more » per data point over a range of more than 10/sup 5/ in the magnitude of the inclusive cross section.« less
The inverse molecular transform index: A descriptor for molecular similarity analysis

The fast Fourier transform of a free-induction decay curve generated by a Fourier operation on a bond distance matrix representation of a molecule gives a frequency domain spectrum that, when plotted as a line of points, is similar to a chromatogram and is called the inverse molecular transform. Within a series of compounds including lower alkanes, alkenes, cyclics, heteroalipathics, and aromatics, the amplitude of the transform ordinates increased directly with the size of the molecule and with going from straight chain to cyclic structures with the same number of carbon atoms. A derived transform index gave a unitary numerical structure descriptor that was used in a topological comparison of structures and is called the transform similarity ratio. With further investigation, this methodology appears to have the potential to generate correlation descriptors, other molecular similarity measures, or an index of protein globularity. © 1993 John Wiley & Sons, Inc.
Powerful immunosuppression mediated by interleukin 2-activated, nonantigen-specific, or H-2-restricted THY-1+ CD8+ cells.

Abstract Normal spleen cells cultured in high or low concentrations of interleukin (IL) 2 for 3 days contain Thy-1 + CD4 − CD8 + cells that powerfully suppress primary but not ongoing or active lymphocyte responses. The precursors of these cells are Thy-1 + AGM-1 − and are absent or present in greatly diminished numbers in athymic and scid mice. Suppression is neither antigen nor H-2 restricted and apparently results from reversible inactivation of resting lymphocytes. Comparable Thy-1 + CD8 + suppressor cells were also recovered from normal spleen cells cultured for 3 days with anti-CD3 antibody without added IL-2, indicating that these cells can be activated during the course of immune responses. Such cells may prevent local recruitment/activation of lymphocytes specific for new epitopes that may be expressed sequentially by proliferating tumor cells or infectious organisms.
Some aspects of mutation

Abstract The existence of an independent metabolism makes the response of freeliving organisms to mutagens more varied than the response of viruses. Materials which inactivate virus can be mutagenic for free-living organisms. Metabolic systems permit organisms to bypass the phenotypic effect of some mutations and may themselves create conditions favoring mutation. The evidence indicates that mutation can take place in the absence of DNA synthesis. A process of base exchange in DNA must account for this class of mutations. However, the lack of segregation following treatment with certain mutagens is not a sufficient argument for mutation in the absence of DNA synthesis and an attempt to develop alternate explanations for the lack of segregation is made. A hypothesis is developed to account for the importance of protein synthesis in the mutation process. The hypothesis assumes that conditions favoring protein synthesis cause the DNA to become “available” for replication and that this “available” stage is a necessary intermediate in DNA synthesis. The period leading to the production of this intermediate is critical for the mutation process as induced by ultraviolet light and by alkylating agents.
Estimation of crop gross primary production (GPP): fAPARchl versus MOD15A2 FPAR

Photosynthesis (PSN) is a pigment level process in which antenna pigments (predominately chlorophylls) in chloroplasts absorb photosynthetically active radiation (PAR) for the photochemical process. PAR absorbed by foliar non-photosynthetic components is not used for PSN. The fraction of PAR absorbed (fAPAR) by a canopy/vegetation (i.e., fAPAR(sub canopy)) derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) images, referred to as MOD15A2 FPAR, has been used to compute absorbed PAR (APAR) for PSN (APARPSN) which is utilized to produce the standard MODIS gross primary production (GPP) product, referred to as MOD17A2 GPP. In this study, the fraction of PAR absorbed by chlorophyll throughout the canopy (fAPAR(sub chl)) was retrieved from MODIS images for three AmeriFlux crop fields in Nebraska. There are few studies in the literature that compare the performance of MOD15A2 FPAR versus fAPAR(sub chl) in GPP estimation. In our study MOD15A2 FPAR and the retrieved fAPAR(sub chl) were compared with field fAPAR(sub canopy) and the fraction of PAR absorbed by green leaves of the vegetation (fAPAR(sub green)). MOD15A2 FPAR overestimated field fAPAR(sub canopy) in spring and in fall, and underestimated field fAPAR(sub canopy) in midsummer whereas fAPAR(sub chl) correctly captured the seasonal phenology. The retrieved fAPAR(sub chl) agreed well with field fAPAR(sub green) at early crop growth stage in June, and was less than field fAPAR(sub green) in late July, August and September. GPP estimates with fAPAR(sub chl) and with MOD15A2 FPAR were compared to tower flux GPP. GPP simulated with fAPAR(sub chl) was corroborated with tower flux GPP. Improvements in crop GPP estimation were achieved by replacing MOD15A2 FPAR with fAPAR(sub chl) which also reduced uncertainties of crop GPP estimates by 1.12-2.37 g C m(sup −2) d(sup −1).
First-order shell-model renormalization in the 1s-0d shell

Abstract It is shown that in the first-order renormalization of the two-body matrix elements in the 1s-0d shell, one must take care in the treatment of the 16O core. Explicitly, when the 16O core is treated as being unperturbed or perturbed in the complete 2hω shell-model space, the results of the renormalization are essentially the same. However, if one treats the 16O core in the Tamm-Dancoff (TDA) subspace of the 2hω model space, the results of the calculation are quite different. The origins of these effects are discussed. The renormalization of the E2 operator is also discussed.
Rapid assessment of antigen induced cytokine expression in memory T cells by flow cytometry

Methods for analysis of T cell responses to specific antigen have traditionally relied on measurements of proliferation or cytokine expression in bulk cultures of PBMC in long term incubations with putative antigen. These techniques suffer from the drawback that they do not enable analysis of single cell responses in the context of unselected cellular backgrounds. It is increasingly important to not only identify cells on the basis of expression of unique surface antigens but also to determine functional and molecular parameters of individual cells in response to a variety of stimuli. We have recently developed methodologies to rapidly assess T-cell subset responses to polyclonal activators and specific antigen in whole blood. These procedures determine the percentages of activated cells and the identification of leucocyte subsets capable of expressing various cytokines and cell surface antigens. Multiparameter analysis of CD69+ /cytokine + expression in T cells in response to specific antigen (e.g. CMV, mumps) demonstrated a range of frequencies from 0.05% to 5.0% within 6 h. Frequencies of responding T cells were consistent but varied depending upon the antigen. Antigen specific T cell responses were host specific and both positively and negatively regulated by antibodies to co-receptors involved in APC-T cell interactions. These technologies will be discussed in terms of application to problems of measuring immune function parameters in disease. The modified technique described in this report is compatible with simple and rapid analysis of clinical samples and provides a means to directly examine the effects of in vivo drug concentrations on T cell immunity. Studies are in progress to examine the sensitivity of this cellular assay to drugs and other therapeutic modalities in clinical samples.
Variation in winter microclimate and its potential influence on Virginia opossum (Didelphis virginiana) survival in Amherst, Massachusetts

If climate limits the geographical distribution of a species, local variation in microclimate may affect the species' local distribution at the edge of its range. We hypothesized that warm urban microclimates may explain the distribution of the Virginia opossum (Didelphis virginiana )i ncentral Massachusetts. We recorded winter temperatures with data-logging sensors in urban, coniferous, deciduous, and open habitats in the human- dominated landscape of the Connecticut River Valley of Massachusetts. Overall, temperatures decreased with elevation. Daily maximum temperatures, a variable used in models of opossum biophysical constraints, were lowest at forested sites, intermediate at urban sites, and highest at open sites; however these were a poor indicator of evening temperatures, which are important to the nocturnal opossum. Open sites had the highest daily temperature fluctuations, and were the coldest at night. Urban and coniferous sites had the least pronounced daily fluctuations in temperature, and urban sites had the warmest nights. Habitat-specific winter temperatures in the Connecticut River Valley indicated that urban sites were most conducive to opossum persistence, but even they were unlikely to sustain populations. Other factors likely help mitigate the influence of harsh climatic conditions on persistence of opossum populations in western Massachusetts.
On the bias and mean-square error of order-restricted maximum likelihood estimators

Abstract An order-restricted (OR) statistical model can be expressed in the general form { P θ | θ ∈ C } , where C is a convex cone in R p . In general, no unbiased estimator exists for θ . In particular, the OR maximum likelihood estimator (ORMLE) is biased, although its aggregate mean square error is usually less than that of the unrestricted MLE (URMLE). Nonetheless, the bias and mean-square error (MSE) of a single component or single linear contrast of the ORMLE can exceed those of the corresponding component or contrast of the URMLE by amounts that approach infinity as the dimension increases. This phenomenon is examined in detail for three examples: the orthant cone, the tree-order cone, and the simple-order cone. The geometric features of the cone that determine the growth rate of the bias and MSE are studied, and bias-reducing adjustments for certain components or contrasts of the ORMLE are suggested for the orthant and tree-order models.
Unthought Thoughts: The Influence of Changing Sensibilities on Penal Policies

Fashions in punishment policies and forms vary with changes in sensibilities (as do fashions in the arts, attitudes towards homosexuality, drug use and religious tolerance). Propositions and polici...
Effect of scavengers in acidolytic cleavage of Cys(Acm)-containing peptides from solid support: Isolation of an ethanedithiol disulfide adduct

Abstract Acidolytic cleavage of C-terminal Cys(Acm)-containing tripeptides from the Wang (HMP) resin can lead to partial deprotection of the Acm group and subsequent disulfide formation. The presence of water and the type of scavenger used in the cocktail mixture were found to play a role in the extent of these impurities formed.
Anticoagulant Treatment in Acute Coronary Occlusion with “So-Called” Ischemic Pattern

1. During the past five years, approximately 200 cases were observed whose clinical history strongly suggested myocardial infarction, but the electrocardiogram showed T wave changes only and, in a few instances T wave changes and minor RS-T segment deviation. In 22 of these patients, after an interval of a day to several weeks, the initial bout of pain was followed by a second, with the development of the typical infarction pattern in the electrocardiogram. 2. Ten of the cases received no anticoagulant treatment—seven because hospitalization was refused, two because their condition was not considered serious enough, and one because of a history of duodenal ulcer. Eight other cases developed the infarction pattern in the electrocardiogram before anticoagulants could be started or given in sufficient amounts. There were five (28 per cent) deaths in this group. 3. The majority of the approximately 200 cases were hospitalized and given anticoagulant treatment. Four of them developed the pattern of myocardial infarction in the electrocardiogram. Two (50 per cent) of these four died. 4. An extension of the myocardial lesion may occur in spite of anticoagulants; but it is our impression that this took place in our subjects most often when anticoagulants were withheld or not given in sufficient amounts. 5. It is not possible to predict accurately the future course of patients who have suffered an acute coronary occlusion and in whom the electrocardiogram may or may not show the typical infarction pattern.
Effectiveness of Al, Ca, and Fe salts for control of internal phosphorus loading in shallow and deep lakes

Internal P loading can maintain high P concentrations and delay eutrophic lake recovery following abatement of external loading. Sediment P inactivation with Al salts has been shown to provide longterm (5–14 years) control of sediment P release; long-term effectiveness of Fe and Ca salts has not been reported. Al toxicity problems are possible unless pH is maintained in the 6-8 range. Vertical transport of hypolimnetic P is unlikely in small, deep, dimictic lakes \((\bar{Z}\sqrt {{{{A}_{0}}}} > 8)\), and effectiveness of P inactivation in lowering their mid-summer epilimnetic P has not been demonstrated. To date, P inactivation has been found to be most effective in improving trophic state in shallow, softwater, polymictic lakes where control of sediment P release affects the entire water column. Abatement of external loading, where necessary, is essential for a successful P inactivation treatment.
MMTV-Wnt1 and -ΔN89β-Catenin Induce Canonical Signaling in Distinct Progenitors and Differentially Activate Hedgehog Signaling within Mammary Tumors

Canonical Wnt/β-catenin signaling regulates stem/progenitor cells and, when perturbed, induces many human cancers. A significant proportion of human breast cancer is associated with loss of secreted Wnt antagonists and mice expressing MMTV-Wnt1 and MMTV-ΔN89β-catenin develop mammary adenocarcinomas. Many studies have assumed these mouse models of breast cancer to be equivalent. Here we show that MMTV-Wnt1 and MMTV-ΔN89β-catenin transgenes induce tumors with different phenotypes. Using axin2/conductin reporter genes we show that MMTV-Wnt1 and MMTV-ΔN89β-catenin activate canonical Wnt signaling within distinct cell-types. ΔN89β-catenin activated signaling within a luminal subpopulation scattered along ducts that exhibited a K18+ER−PR−CD24highCD49flow profile and progenitor properties. In contrast, MMTV-Wnt1 induced canonical signaling in K14+ basal cells with CD24/CD49f profiles characteristic of two distinct stem/progenitor cell-types. MMTV-Wnt1 produced additional profound effects on multiple cell-types that correlated with focal activation of the Hedgehog pathway. We document that large melanocytic nevi are a hitherto unreported hallmark of early hyperplastic Wnt1 glands. These nevi formed along the primary mammary ducts and were associated with Hedgehog pathway activity within a subset of melanocytes and surrounding stroma. Hh pathway activity also occurred within tumor-associated stromal and K14+/p63+ subpopulations in a manner correlated with Wnt1 tumor onset. These data show MMTV-Wnt1 and MMTV-ΔN89β-catenin induce canonical signaling in distinct progenitors and that Hedgehog pathway activation is linked to melanocytic nevi and mammary tumor onset arising from excess Wnt1 ligand. They further suggest that Hedgehog pathway activation maybe a critical component and useful indicator of breast tumors arising from unopposed Wnt1 ligand.
Delineating (and delimiting) the boundary spanning role of the medical public information officer

Abstract Medical public information officers serve as boundary spanners between medical experts and journalists. Editors at every daily newspaper in Pennsylvania and cardiac surgeons in Pennsylvania were surveyed about the role of medical PIOs. While the two groups expressed many similar opinions, editors generally were more open to medical PIOs as boundary spanners, whereas surgeons preferred to handle their own media relations.
Compensation of Time Delay in a Network-based Gait Rehabilitation System with a Discrete-time Communication Disturbance Observer*

Abstract In this paper, a network-based gait rehabilitation system is proposed for enhanced mobility and tele-rehabilitation. In the proposed rehabilitation system, a compact rotary elastic actuator (cRSEA) is employed to provide assistive torque to the patients and it is controlled over a local wireless network. However, time delay exists in both sensor-controller and controller-actuator channels, which leads to performance degradation and even destabilization. Moreover, the amount of time delay is time-varying and it is difficult to measure accurately. In order to compensate the time delay and guarantee stability of the system, a communication disturbance observer (CDOB) is designed in the discrete-time domain. Parameters are tuned based on the linear quadratic regulator (LQR) design technique and compared to other parameter choices in the frequency domain in terms of closed-loop stability, tracking performance, disturbance attenuation, and noise cancellation. Simulation and experimental results are shown to validate the performance of the proposed controller.
Stable Isotope (N, C, Hg) Study of Methylmercury Sources and Trophic Transfer in the Northern Gulf of Mexico

We combined N, C, and Hg stable isotope measurements to identify the most important factors that influence MeHg accumulation in fish from the northern Gulf of Mexico (nGOM), and to determine if coa...
A Comparison of the Minimum Current Corona to a Magnetohydrodynamic Simulation of Quasi-Static Coronal Evolution

We use two different models to study the evolution of the coronal magnetic field that results from a simple photospheric field evolution. The first, the minimum current corona (MCC), is a self-consistent model for quasi-static evolution that yields an analytic expression approximating the net coronal currents and the free magnetic energy stored by them. For the second model calculation, the nonlinear, time-dependent equations of ideal magnetohydrodynamics are solved numerically subject to line-tied photospheric boundary conditions. In both models high current density concentrations form vertical sheets along the magnetic separator. The time history of the net current carried by these concentrations is quantitatively similar in each of the models. The magnetic energy of the line-tied simulation is significantly greater than that of the MCC, in accordance with the fact that the MCC is a lower bound on energies of all ideal models. The difference in energies can be partially explained from the different magnetic helicity injection in the two models. This study demonstrates that the analytic MCC model accurately predicts the locations of significant equilibrium current accumulations. The study also provides one example in which the energetic contributions of two different MHD constraints, line-tying constraints and flux constraints, may be quantitatively compared. In this example line-tying constraints store at least an order of magnitude more energy than do flux constraints.
Strength and ductility of compact-flange I-girders in negative bending

Abstract This paper reviews available experimental and finite element test data pertaining to the negative moment-plastic rotation behavior of continuous-span steel I-girders with compact or ultra-compact flanges. Current American specification formulas for the pier-section strength of these types of members and a moment-plastic rotation model recently developed by the authors are examined against the experimental and finite element test results. Several weaknesses in current specification provisions are observed. The new M-θp model avoids these weaknesses and provides a lower-bound approximation of the complete moment-plastic rotation response at the pier section.
Fifth Pivotal Research in Cardiology in the Elderly (PRICE-V) symposium: preventive cardiology in the elderly-executive summary. Part I: morning session.

The Pivotal Research in Cardiology in the Elderly (PRICE) conference series was established in 1999 as a mechanism for bringing together leading investigators and clinicians to review recent major advances in cardiovascular aging research and to identify specific research priorities for the years ahead. The first symposium addressed a broad range of topics relevant to cardiovascular disease in the elderly, while subsequent conferences focused on acute coronary syndromes, heart failure, and heart rhythm disturbances in older people.1–4 PRICE-V, “Preventive Cardiology in the Elderly”, was held on November 8, 2008 in New Orleans, LA. The conference began with a plenary lecture that provided an overview of the societal burden of cardiovascular disease in the elderly which set the stage for the remainder of the meeting. This was followed by a series of six 1-hour sessions that addressed specific aspects of preventive cardiology in the elderly. Each session comprised 3 presentations by leading investigators followed by a discussion period chaired by a prominent authority in the field. The program concluded with a second plenary lecture summarizing the conference proceedings, outlining future research directions, and providing a framework for action. PRICE-V was sponsored by the Society of Geriatric Cardiology in collaboration with the American Society for Preventive Cardiology. The meeting was coordinated by the Continuing Medical Education (CME) office of the Washington University School of Medicine in St. Louis, MO. The conference was supported by a grant from the National Institute on Aging. Attendees included, among others, four recipients of Young Investigator Travel Awards. The remainder of this document summarizes the PRICE-V proceedings.
Undocumented Latina immigrants in Orange County, California: a comparative analysis.

"This article examines a unique data set randomly collected from Latinas (including 160 undocumented immigrants) and non-Hispanic white women in Orange County, California, including undocumented and documented Latina immigrants, Latina citizens, and non-Hispanic white women. Our survey suggests that undocumented Latinas are younger than documented Latinas, and immigrant Latinas are generally younger than U.S.-citizen Latinas and Anglo women. Undocumented and documented Latinas work in menial service sector jobs, often in domestic services. Most do not have job-related benefits such as medical insurance.... Despite their immigration status, undocumented Latina immigrants often viewed themselves as part of a community in the United States, which significantly influenced their intentions to stay in the United States. Contrary to much of the recent public policy debate over immigration, we did not find that social services influenced Latina immigrants' intentions to stay in the United States."
Efficient cryo-cooled 2.7-µm Er 3+ -doped Y 2 O 3 ceramic laser diode-pumped at 974 nm

Reported here is the first cryogenically-cooled diode-pumped performance of Er3+:Y 2 O 3 laser based on 4 I 11/2 ⇒ 4 I 13/2 transitions. Pump-limited CW power of over 1.6 W at ∼2.7 µm was achieved with the 27.5% slope efficiency.