cssi/SciSciGPT-SciSciNet huggingface dataset:
EFFECT OF EARLY THYMECTOMY ON DEVELOPMENT OF RENAL TUMORS IN LUCKÉ TUMOR HERPESVIRUS-INFECTED LEOPARD FROGS

ABSTRACT The Lucke tumor of northern leopard frogs, Rana pipiens , provides an interesting model system to study development of tumors. It is relatively easy to induce renal tumors in metamorphosing frogs by injection of Lucke tumor herpesvirus (LTHV) into embryos, but it is difficult to induce tumors by injection of viruses into immunocompetent larvae or adults. We have begun to study whether debilitation of the thymus-dependent immune system during the larval period may affect tumor incidence in virus-infected frogs. Thymectomy (tx) at 2–3 weeks post-fertilization (Taylor-Kollros Stages II-III) reduced the number of splenic and blood lymphocytes, reduced in vitro lymphocyte responses to the mitogen, PHA, and prolonged survival of Lucke tumor implants. Thymectomy did not diminish in vitro responses to LPS, a T-independent mitogen (Rollins and Cohen, 1980). In spite of these significant reductions in T-cell responses measured in tadpoles 1–2 months post-thymectomy, tumor incidence in premetamorphic or metamorphosing frogs, injected as embryos with LTHV, was the same in thymectomized and normal immunocompetent animals. This suggests that: a) T-cell dependent immunity does not play a major role in the prevention of tumor development in immunocompetent larvae, and b) if tumor-specific transplantation antigens appear, they may induce tolerance rather than immunity in LTHV-injected frogs.
Calculations of low-frequency wind noise along a low two-dimensional hill surface

Measurement of outdoor sound propagation is often limited by wind noise, i.e. pressure fluctuations from atmospheric turbulence, especially for infrasound and low audible frequencies. Over a flat ground surface, the spectral density of wind noise can be predicted by the shear-turbulence mechanism for static pressure fluctuations using a mirror flow atmospheric turbulence model for the inhomogeneous surface-blocking effect. This study moves beyond a flat ground model to consider the effects of flow distortion by weak topography on surface wind noise, specifically, flow over a low two-dimensional hill, free from separation, at large Froude number. The integral solution for the pressure Poisson equation is used as a starting point, with turbulence modeled by the mirror flow in surface-following coordinates. The perturbation analysis of Hunt et al. [Q. J. R. Meteorol. Soc. 114(484), 1435–1470 (1988)] is used to model the mean shear rate as a function of elevation and distance over the hill. For upwind, downwi...
UNIT 6.2 Preparation of Soluble Proteins from Escherichia coli

Purification of human IL-1β is used in this unit as an example of the preparation of soluble proteins from E. coli. Bacteria containing IL-1β are lysed, and IL-1 β in the resulting supernatant is purified by anion-exchange chromatography, salt precipitation and cation-exchange chromatography, and then concentrated. Finally, the IL-1 β protein is applied to a gel-filtration column to separate it from remaining higher- and lower-molecular-weight contaminants, the purified protein is stored frozen or is lyophilized. The purification protocol described is typical for a protein that is expressed in fairly high abundance (i.e., >5% total protein) and accumulates in a soluble state.
Cytokine Circuits in Cardiovascular Disease

Arterial inflammation is a hallmark of atherosclerosis, and appropriate management of this inflammation represents a major unmet therapeutic need for cardiovascular disease patients. Here, we review the diverse contributions of immune cells to atherosclerosis, the mechanisms of immune cell activation in this context, and the cytokine circuits that underlie disease progression. We discuss the recent application of these insights in the form of immunotherapy to treat cardiovascular disease and highlight how studies on the cardiovascular co-morbidity that arises in autoimmunity might reveal additional roles for cytokines in atherosclerosis. Currently, data point to interleukin-1β (IL-1β), tumor necrosis factor (TNF), and IL-17 as cytokines that, at least in some settings, are effective targets to reduce cardiovascular disease progression.
Structural change in Asia, the real effective exchange rate, and agricultural productivity

It is argued in this paper that agriculture plays a here-to-for unrecognized role in the process of structural change. In very poor countries agriculture is the key sector in the economy and agricultural prices greatly influence the overall price level in such an economy. It is hypothesized that if agricultural productivity grows faster than manufacturing productivity this will, under certain conditions, cause the price of the former to fall relative to the latter which in turn implies that the overall price level in the economy should fall, ceteris paribus. This results in a fall in the real effective exchange rate, ceteris paribus. This decline increases the competitiveness of producing tradable goods, in particular manufactured goods. Thus the process of structural change (shifting employment and resources out of agriculture) becomes easier. These hypotheses are empirically analyzed utilizing a data set for twelve Asian countries for an extended time period.
A 0.36pJ/bit Analog PUF Based on Current Steering DAC and VCO

This paper proposes an analog weak physical unclonable function (PUF). The proposed PUF derives its unique key from random mismatch in a cascode current steering thermometer digital-to-analog converter (DAC). The DAC drives a voltage-controlled 7-stage ring oscillator (RO). MSB of the difference in phase outputs of two ROs generate the PUF response. An N-bit PUF key can be produced from a single proposed PUF cell by running the VCOs for N sampling periods which results in the proposed PUF having the lowest area/bit among weak PUFs. A prototype fabricated in 65nm has an intra-HD of 0.0906 and inter-HD of 0.4859 for 2048-bit PUF key.
Seeking Acceptance: LGBTQ and Membership in Alcoholics Anonymous (AA)

This is a qualitative account of LGBTQ experiences seeking recovery in Alcoholics Anonymous. Tracing back over the past four decades, personal stories of recovery reflect the struggles with getting...
An Active Learning Method for the Comparison of Agent-based Models

We develop a methodology for comparing two or more agent-based models that are developed for the same domain, but may differ in the particular data sets (e.g., geographical regions) to which they are applied, and in the structure of the model. Our approach is to learn a response surface in the common parameter space of the models and compare the regions corresponding to qualitatively different behaviors in the models. As an example, we develop an active learning algorithm to learn phase transition boundaries in contagion processes in order to compare two agent-based models of rooftop solar panel adoption.
Teaching NeuroImage: Human Polymerase Gamma Gene (POLG) Disorder Presenting as Refractory Status Epilepticus.

A 31-year-old woman with severe childhood-onset dysmotility syndrome was admitted for encephalopathy and seizures. Video EEG demonstrated electrographic seizures of multifocal onset refractory to multiple antiseizure medications (figure 1, A and C). MRI of the brain revealed multiple hyperintensities (figure 1B) that progressed (figure 1D). Infectious, immunologic, and neoplastic workup was unremarkable. A comprehensive epilepsy panel demonstrated a human polymerase gamma gene (POLG) likely pathogenic variant, c.3401 (c.3401A>G), previously reported as recessive, and a novel variant of unknown significance, c.2725 (c.2725 G>A). We hypothesize both variants are predicted to act in a compound heterozygous fashion. POLG disorders present with a discrete phenotype in adults; diagnosis is critical as valproate can precipitate liver failure1,2 (figure 2).
Examining the Statistical Relationships between Volcanic Seismic, Infrasound, and Electrical Signals: A Case Study of Sakurajima Volcano, 2015

Abstract Sakurajima volcano in Japan is known for frequent eruptions containing prolific volcanic lightning. Previous studies from eruptions at Redoubt have shown preliminary correlations between seismic, infrasound, and radio frequency signals. This study uses field data collected at Sakurajima from 28 May–7 June 2015 and multivariable statistical modeling to quantify these relationships. We build regression equations to examine each of the following parameters of electrical activity: (1) the presence of electrical activity, (2) the presence of the radio frequency signal called continual radio frequency impulses (CRF), (3) the presence of lightning, (4) the overall duration of electrical activity, and (5) the total number of radio frequency sources located by a lightning mapping array. We model these response variables against: (1) seismic energy, (2) infrasound energy, (3) seismic duration, (4) infrasound duration, and (5) the volcano acoustic seismic ratio. Our final regression equations show that each parameter of electrical activity is best defined by a separate set of response parameters, but overall events with greater explosivity correlate with higher amounts of electrical activity. Specifically, (1) the probability of CRF occurring, and the overall number of located radio frequency sources are likely related to deeper fragmentation depths; (2) the probability of electrical activity occurring at all, and specifically the probability of lightning being generated are correlated with high infrasound energies indicating that the gas thrust phase of plume formation plays an important role in charge generation; and (3) the longer an eruption (as determined by the duration of the infrasound signal) the longer we can expect to see radio frequency signals generated.
The Impact of Biological Sex on the Outcomes of Spinal Cord Stimulation in Patients with Chronic Pain.

Background Spinal cord stimulation continues to gain increasing popularity in the pain management field for the treatment of different painful conditions, however to-date, the correlation between the spinal cord stimulator effectiveness and biological sex has not been fully established. We aim to investigate the correlation between the biological sex and spinal cord stimulation (SCS) outcomes. Methods Following Institutional Review Board approval, a retrospective cohort study was performed by collecting data for patients treated with SCS at a tertiary academic center between the years 2002 and 2019. We used multivariable linear regression model to assess the association between biological sex and pain scores at baseline, 6 and 12-months following SCS implantation. Propensity score matching (PSM) was performed based on a set of covariates including: age, duration of pain, time since implant, BMI, opioid medications use, smoking, depression and history of alcohol or substance abuse. Results Of the patients treated with SCS implants, 418 patients fit the inclusion and exclusion criteria, out of which the majority were females (272, 65 %). The pre-matching data reported a significant difference in history of diabetes and depression and was also significant for more opioid use in male patients at baseline and 6-months and 12-months post-SCS implant. Propensity score matching (PSM) was performed based on the above mentioned covariant. After matching, no statistical difference was found among the variables, in both groups. Furthermore, there were no significant differences in outcome measures, i.e., pain scores at baseline and 6- and 12-months post-implant, in both groups after matching. Conclusion No sex-based differences in the analgesic response to SCS therapy was detected at 6 and 12 months post-implant between groups with similar demographics, biomedical and psychological values.
On a Complementary Energy Principle in Linear Thermoelasticity

Use is made of the summation convention. A comma preceding a subscript indicates differentiation with respect to that variable, except that i (or j) after a comma stands for differentiation with respect to the Cartesian coordinate x% (or Xj). In the above equations, m = rji denotes the components of stress if the temperature increment 6 above a reference absolute temperature T vanishes. The total stress, in general, is thus Tij — (308ij (8ij is the Kronecker delta). Further, u* and s% indi­ cate the components of solid and entropy displacement, respec­ tively, k is the coefficient of heat conduction, and p = d/dt is a time operator. W is Biot's thermoelastic potential, which con­ sists of the sum of the isothermic mechanical energy (expressed here as a quadratic function of the stresses T»,-) and the term cd2/2T, where c is the specific heat of the unit volume in the absence of elastic deformation. It is recalled that the entropy displacement Si is related to entropy s by the equation s = — 5»,». Eq. (1) represents the stress equation of equilibrium, in which the body force was omitted for simplicity. Eq. (2) is a particular form of the heat conduction equation. Eq. (3) is the (isothermal) stress-displacement relation (Hooke's law), and Eq. (4) may be called the "thermal" stress-displacement relation. Biot has shown in reference 1 that Eqs. (1) and (2) may be derived by a variational procedure if the validity of Eqs. (3) and (4) is assumed. Since Biot applied the variation to the displace­ ments Ut and Si, his procedure appears to correspond to Green's method. Thus, the question may be asked whether it might not be feasible to establish, for thermoelasticity, an associated principle of complementary energy which would then correspond to Castigliano's method in elasticity. The availability of such an extremum principle could be of considerable significance in the development of approximate methods of thermoelastic structural analysis. In what follows, it is shown that it is, in fact, possible to formu­ late such a principle complementary to Biot's procedure. For the sake of brevity, the principle will not be presented here in its most general form. This applies in particular to the restriction in the type of boundary conditions. We consider the functional
SU-E-T-556: Monte Carlo Generated Dose Distributions for Orbital Irradiation Using a Single Anterior-Posterior Electron Beam and a Hanging Lens Shield

Purpose: Various cancers of the eye are successfully treated with radiotherapy utilizing one anterior-posterior (A/P) beam that encompasses the entire content of the orbit. In such cases, a hanging lens shield can be used to spare dose to the radiosensitive lens of the eye to prevent cataracts. Methods: This research focused on Monte Carlo characterization of dose distributions resulting from a single A-P field to the orbit with a hanging shield in place. Monte Carlo codes were developed which calculated dose distributions for various electron radiation energies, hanging lens shield radii, shield heights above the eye, and beam spoiler configurations. Film dosimetry was used to benchmark the coding to ensure it was calculating relative dose accurately. Results: The Monte Carlo dose calculations indicated that lateral and depth dose profiles are insensitive to changes in shield height and electron beam energy. Dose deposition was sensitive to shield radius and beam spoiler composition and height above the eye. Conclusion: The use of a single A/P electron beam to treat cancers of the eye while maintaining adequate lens sparing is feasible. Shield radius should be customized to have the same radius as the patient’s lens. A beam spoiler should be used if itmore » is desired to substantially dose the eye tissues lying posterior to the lens in the shadow of the lens shield. The compromise between lens sparing and dose to diseased tissues surrounding the lens can be modulated by varying the beam spoiler thickness, spoiler material composition, and spoiler height above the eye. The sparing ratio is a metric that can be used to evaluate the compromise between lens sparing and dose to surrounding tissues. The higher the ratio, the more dose received by the tissues immediately posterior to the lens relative to the dose received by the lens.« less
HIV-Related Cognitive Impairment of Orphans in Myanmar With Vertically Transmitted HIV Taking Antiretroviral Therapy.

Abstract Objective We determined the effect of perinatally acquired HIV on neurocognition in Myanmar children treated with antiretroviral therapy by comparison to demographically matched seronegative children. Background Myanmar has one of the highest HIV-1 prevalence rates in Southeast Asia. Studies from other resource-poor countries have shown that HIV-infected children differ in socioeconomic, nutritional and caregiver status compared to normal controls. Some vertically infected orphans in Myanmar reside separately from HIV-uninfected children in separate orphanages, thus the demographic variables of interest are naturally controlled. This study provides a unique evaluation of the neurocognitive effects of HIV in children, with control over key demographic variables. We hypothesized that HIV-infected orphans would perform significantly worse on cognitive indices compared with HIV-negative orphans. Design/Methods A battery of cognitive tests sensitive to HIV-associated impairments in children was administered to 28 perinatally acquired HIV-positive children and 31 HIV-negative children from two orphanages in Myanmar; 21 children from each cohort underwent testing at baseline and again after 12 months. Results Baseline comparison of the two groups indicated that the HIV-infected children performed poorly across all tests, with significant group differences in executive function, visuospatial reasoning, fine motor dexterity, and visual motor integration. On subsequent testing, both cohorts of children showed improvements across multiple domains, with no significant effect of age at treatment initiation. Conclusions Our results demonstrate a strong effect of HIV infection on specific neurocognitive deficits in vertically infected children. Understanding viral and host determinants and timing and choice of antiretroviral therapy on cognition will be critical to preventing cognitive impairment of children with HIV.
Librarians, Libraries, and the Scholarship of Teaching and Learning

Librarians are continually teaching students and faculty how to identify and access learning resources. They teach during individual reference consultations, through presentations to classes, and through library website content they create. Are librarians well prepared to design and deliver well-crafted instruction? Academic librarians have plentiful resources for developing their pedagogical knowledge through the activities of the Association of College and Research Libraries (ACRL), whose extensive professional development initiatives to advance effective pedagogy are described. The ACRL's definitions of the components of information literacy skills and instructional competencies, described in the chapter, are relevant and important to all teaching faculty. The chapter discusses some of the benefits and outcomes that can arise from librarians’ efforts to build and sustain active collaborations with discipline-specific teaching faculty. Because the library can be at the center of connections among all of the university's academic units, it is well placed to create and support initiatives that develop cross-disciplinary pedagogical excellence. Beyond their intentional efforts to make teaching and learning resources available for faculty, academic libraries can participate in campus-wide programs such as an Institutional Repository or a Center for Teaching and Learning that will promote steady growth in the excellence of the university's teaching and learning.
Engraftment and Retroviral Marking of CD34+ and CD34+CD38− Human Hematopoietic Progenitors Assessed in Immune-Deficient Mice

Retroviral-mediated transduction of human hematopoietic stem cells to provide a lifelong supply of corrected progeny remains the most daunting challenge to the success of human gene therapy. The paucity of assays to examine transduction of pluripotent human stem cells hampers progress toward this goal. By using the beige/nude/xid ( bnx )/hu immune-deficient mouse xenograft system, we compared the transduction and engraftment of human CD34 + progenitors with that of a more primitive and quiescent subpopulation, the CD34 + CD38 − cells. Comparable extents of human engraftment and lineage development were obtained from 5 × 10 5 CD34 + cells and 2,000 CD34 + CD38 − cells. Retroviral marking of long-lived progenitors from the CD34 + populations was readily accomplished, but CD34 + CD38 − cells capable of reconstituting bnx mice were resistant to transduction. Extending the duration of transduction from 3 to 7 days resulted in low levels of transduction of CD34 + CD38 − cells. Flt3 ligand was required during the 7-day ex vivo culture to maintain the ability of the cells to sustain long-term engraftment and hematopoiesis in the mice.
Early recognition of rheumatoid disease with comments on treatment.

WITHIN the past 10 years, increasing attention has been focused on children with chronic deforming arthritis. With few exceptions, such children have claimed interest of those concerned primarily with rheumatoid arthritis in adults, orthopedic surgeons and workers in the field of physical medicine, to whom these patients have presumably been referred for care by pediatricians and general practitioners. Lack of general pediatric interest in this disease is suggested by the small number of pertinent papers in the pediatric literature. Furthermore, the relative lack of importance of these children in the general thinking of students of arthritis is suggested by the fact that a current statistical study of the incidence and prevalence of rheumatoid arthritis in a large American metropolitan area has been arbitrarily limited to patients 15 years of age or older. Is rheumatoid arthritis sufficiently common within the pediatric group to deserve pediatric attention? Although there have been only a few statistical studies, the available evidence suggests that the incidence of new cases in the general population, under 15 years of age, is roughly the same for rheumatoid arthritis, diabetes mellitus and nephrosis, approximately 3 new cases per 100,000 persons under 15 years of age each year. In round numbers, 1200 new cases of rheumatoid arthritis, of diabetes and of nephrosis occur annually within the childhood population of this country. Parallel comparison of the amounts of attention paid to these three groups of patients by pediatricians would belabor the point. These juvenile victims of rheumatoid arthritis certainly deserve increasing pediatric attention, and we suggest that they also present many stimulating challenges.
Effects of gendered behavior on testosterone in women and men

Testosterone is typically understood to contribute to maleness and masculinity, although it also responds to behaviors such as competition. Competition is crucial to evolution and may increase testosterone but also is selectively discouraged for women and encouraged for men via gender norms. We conducted an experiment to test how gender norms might modulate testosterone as mediated by two possible gender→testosterone pathways. Using a novel experimental design, participants (trained actors) performed a specific type of competition (wielding power) in stereotypically masculine vs. feminine ways. We hypothesized in H1 (stereotyped behavior) that wielding power increases testosterone regardless of how it is performed, vs. H2 (stereotyped performance), that wielding power performed in masculine but not feminine ways increases testosterone. We found that wielding power increased testosterone in women compared with a control, regardless of whether it was performed in gender-stereotyped masculine or feminine ways. Results supported H1 over H2: stereotyped behavior but not performance modulated testosterone. These results also supported theory that competition modulates testosterone over masculinity. Our findings thus support a gender→testosterone pathway mediated by competitive behavior. Accordingly, cultural pushes for men to wield power and women to avoid doing so may partially explain, in addition to heritable factors, why testosterone levels tend to be higher in men than in women: A lifetime of gender socialization could contribute to “sex differences” in testosterone. Our experiment opens up new questions of gender→testosterone pathways, highlighting the potential of examining nature/nurture interactions and effects of socialization on human biology.
Artillery of Heaven: American Missionaries and the Failed Conversion of the Middle East by Makdisi, U

At the center of Ussama Makdisi's new book is a small, tragic, and deceptively simple story. It involves on the one side a tiny handful of missionaries from the United States, brimming with faith, ...
Understanding emergent dynamics: Using a collective activity coordinate of a neural network to recognize time-varying patterns

In higher animals, complex and robust behaviors are produced by the microscopic details of large structured ensembles of neurons. I describe how the emergent computational dynamics of a biologically based neural network generates a robust natural solution to the problem of categorizing time-varying stimulus patterns such as spoken words or animal stereotypical behaviors. The recognition of these patterns is made difficult by their substantial variation in cadence and duration. The neural circuit behaviors used are similar to those associated with brain neural integrators. In the larger context described here, this kind of circuit becomes a building block of an entirely different computational algorithm for solving complex problems. While the network behavior is simulated in detail, a collective view is essential to understanding the results. A closed equation of motion for the collective variable describes an algorithm that quantitatively accounts for many aspects of the emergent network computation. The feedback connections and ongoing activity in the network shape the collective dynamics onto a reduced dimensionality manifold of activity space, which defines the algorithm and computation actually performed. The external inputs are weak and are not the dominant drivers of network activity.
Specific and non-specific natural killer cell responses to viral infection.

Initially identified by their ability to kill tumor cells without prior sensitization of the host, natural killer (NK) cells are now known to provide a crucial initial defense against pathological organisms. In particular, they play a critical role during the early phases of infection (days 0 to 5) while specific immunity develops (reviewed in [1]). Recent advances, however, indicate that NK cells specifically recognize virus-infected cells in a manner akin to their recognition of tumor cells, and also respond non-specifically to viral infections.
Chronic treatment with meta-chlorophenylpiperazine (m-CPP) alters behavioral and cerebral metabolic responses to the serotonin agonists m-CPP and quipazine but not 8-hydroxy-2(di-N-propylamino)tetralin

The effects of the serotonin (5-HT) agonists meta-chlorophenylpiperazine (m-CPP), quipazine and 8-hydroxy-2(di-n-propylamino)tetralin (DPAT) on behavior and on regional cerebral metabolic rates for glucose (rCMRglc) were measured in control rats or in rats pretreated for 2 weeks with continuous infusion of saline or m-CPP (2.5 mg/kg/day, subcutaneously). rCMRglc was measured in 71 brain regions, using the quantitative autoradiographic [14C]2-deoxy-D-glucose technique, at 15 min after acute administration of m-CPP 2.5 mg/kg, 60 min after quipazine 20 mg/kg, or 10 min after DPAT 1 mg/kg. Behavioral effects were assessed for m-CPP with an activity monitor, for quipazine by counting head shakes and for DPAT by scoring the serotonin syndrome. Chronic m-CPP pretreatment produced tolerance to hypolocomotion induced by acute m-CPP and to head shakes caused by acute quipazine, but did not alter the serotonin syndrome produced by DPAT. m-CPP 2.5 mg/kg IP produced widespread rCMRglc reductions in control rats but failed to modify rCMRglc in any region after chronic m-CPP pretreatment. Quipazine increased rCMRglc in 4 regions in control rats, but reduced rCMRglc in 14 brain areas of chronically m-CPP-pretreated animals. DPAT altered rCMRglc to the same degree in control (25 regions affected) and in chronically m-CPP-pretreated rats (28 regions affected). Reduced behavioral and metabolic effects of acute m-CPP in chronically m-CPP-pretreated rats were not due to pharmacokinetic alterations. These results demonstrate that chronic administration of m-CPP produces behavioral and metabolic tolerance to acute administration of m-CPP, but not of DPAT. They suggest that hypolocomotion and the serotonin syndrome are mediated by different 5-HT receptor subtypes, and that chronic m-CPP administration produces functional down-regulation of 5-HT1B/1C but not of 5-HT1A-coupled mechanisms.
Structure and torsional flexibility of the linkage between guanine and fluorene residues in the deoxyguanosine–aminofluorene and deoxyguanosine–acetylaminofluorene carcinogenic adducts

Potential energy surfaces for rotations around two central CN bonds in N-(deoxyguanosin-8-yl)-2-acetylaminofluorene (AAF–dG) and its deacetylated derivative (AF–dG) were studied using Amber 95 molecular mechanics. Both of these adducts are known to be strong mutagens and carcinogens. New Amber 95 force field parameters were derived for the linkage connecting guanine and fluorene moieties in AAF–dG and AF–dG. For this purpose, we determined ab initio MP2/cc-pVDZ//B3-LYP/6-31G* and polarized continuum model Hartree–Fock/6-31G* potential energy surfaces of smaller model systems that included the N-methylimidazole–acetylaniline and N-methylimidazole–aniline adducts. The molecular mechanics parameters were adjusted to minimize differences between the gas-phase ab initio and molecular mechanics surfaces of these model systems. The resulting parameters were transferred to AF–dG and AAF–dG. The barrier for the rotation of the fluorene residue in AF–dG was found to be less than 2 kcal/mol. Such a small barrier renders the fluorene moiety freely rotatable at room temperature. In contrast, the fluorene rotation in AAF–dG is hindered by a significantly larger barrier of 10 kcal/mol. This barrier corresponds to conformations in which the fluorene and acetyl groups lie in the same plane, and is largely due to steric repulsion. Similarly, the coplanar arrangement of guanine and the bridging amino or acetyl groups is disfavored by 5–10 kcal/mol, with AAF–dG again being the more rigid of the two molecules. Energy minima for a rotation around a bond between guanine and the bridging nitrogen are found at ±80° in AAF–dG, and at 120° and −90° for AF–dG. Overall, the fluorene–dG linkages in AF–dG and AAF–dG adducts have significantly different equilibrium structures and torsional flexibilities. These differences may be contributing factors for the observed disparity in mutagenic effects of these adducts.
Wavelet-based recognition using model theory for feature selection

An increase in accuracy and reduction in computational complexity of the common wavelet- based target recognition techniques can be achieved by using interpretable features for recognition. In this work, the Best Discrimination Basis Algorithm (BDBA) is applied to select the most discriminant complete orthonormal wavelet basis for recognition purposes. The BDBA uses a relative entropy criterion as a discriminant measure. Then, interpretable features are selected from the most discriminant basis by utilizing symbolic knowledge about the domain. The domain theory that contains this symbolic knowledge is implemented in a backpropagation neural network. The output of the backpropagation neural network gives a final recognition decision. The results of our simulations show that the recognition accuracy of the proposed Automatic Feature Based Recognition System (AFBRS) is better than the recognition accuracy of a system that performs recognition using the Most Discriminant Wavelet Coefficients (MDWC).
11β-Hydroxylation and carnitine-dependent fatty acid oxidation in adrenal mitochondria☆

Abstract 14 C-palmitate can be oxidized to 14 C-CO 2 in rat adrenal homogenates. Carnitine stimulates this conversion threefold. In the presence of carnitine, ketone bodies are also formed, whereas in its absence, none are detected. Carnitine-palmityl transferase activity can be demonstrated in intact as well as detergent-treated mitochondria. 11β-hydroxylation in isolated rat adrenal mitochondria can be supported by palmitate, ATP and coenzyme A, or palmityl coenzyme A if carnitine is present. The activity supported by palmityl CoA + carnitine or palmitylcarnitine alone is 5–30% of the activity with 10 m m 2-oxoglutarate or 5 m m isocitrate, substrates which produce maximal rates of 11β-hydroxylation. The addition of catalytic amounts of malate (0.2 m m , a level which does not support 11β-hydroxylation) increases the activity with palmitylcarnitine or palmityl CoA + carnitine to levels comparable to those obtained with 2-oxoglutarate and isocitrate. Although fluorocitrate inhibits citrate-supported 11β-hydroxylation, it has no effect on 11β-hydroxylation supported by palmitylcarnitine or palmityl CoA + carnitine in the presence of malate. In contrast, amytal and dinitrophenol (DNP) are markedly inhibitory. Oxidation of long-chain fatty acids in rat adrenal mitochondria occurs predominately via a carnitine-stimulated pathway. This activity is capable of supporting 11β-hydroxylation via a pathway in which the NADH formed during β-oxidation is coupled to the energy-dependent transhydrogenase for the generation of NADPH. Maximal rate of 11β-hydroxylation in isolated mitochondria can be obtained with physiological levels of intermediates in fatty acid oxidation in contrast to the high concentration of citric acid cycle intermediates required.
TEMPERATURE DEPENDENCE OF GROWTH AND PHOSPHORUS UPTAKE IN TWO SPECIES OF VOLVOX (VOLVOCALES, CHLOROPHYTA)1

The growth of Volvox globator L. and Volvox aureus Ehr. was measured at five temperatures and nine phosphorus concentrations. Growth rates were hyperbolically related to phosphorus concentrations for all temperatures using a Monod growth model. Optimal growth rates of 1.17 and 1.00 doublings d−1 were obtained at 20°C for V. globator and V. aureus, respectively. Neither species grew at 5°C. The half-saturation constants for growth, Ks, were lower for V. aureus. Phosphorus uptake by both species was also dependent upon external phosphorus concentrations and temperature. At all temperatures, maximum phosphorus uptake (μmol P colony−1 min−1) was similar for both species; however, the half-saturation constants for uptake showed significant differences between the species. Comparisons of the kinetic constants for growth and phosphorus uptake suggest that V. aureus will outcompete V. globator under phosphorus limited, conditions.
A Meta-Analysis of the Relative and Interactive Effects of Ability and Motivation on Performance

There is a longstanding belief that performance is a function of the interaction between ability and motivation. However, empirical tests of this interaction have produced inconsistent results. The...
Tricinonoic acid and tricindiol, two new irregular sesquiterpenes from an endophytic strain of Fusarium tricinctum

Two new rare irregular sesquiterpenes, tricinonoic acid (1) and tricindiol (2), and the known furanopyrrolidones, NG-391 (3) and NG-393 (4), have been isolated from an EtOAc extract of Fusarium tricinctum, a fungus endophytic in the root tissue of the Sonoran desert plant, Rumex hymenosepalus. The structures of 1 and 2 were elucidated on the basis of their high-resolution mass, 1D and 2D NMR spectroscopic data. A possible biosynthetic route to 1 and 2 from farnesyl diphosphate is proposed.
Compensation for the soliton self-frequency shift and the third-order dispersion using bandwidth-limited optical gain

Abstract Soliton self-frequency shift and third-order dispersion are the forces destructive of pulse propagation in ultrahigh-bit-rate (>100 Gbits/s) optical transmission systems. These effects can be compensated for by the proper choice of finite optical gain and the dispersion parameters of the optical fiber. Numerical simulation of the conditions under which these effects can be compensated for leading to stable soliton propagation are given.
Experimental approaches for assessing interfacial behavior of polymer films during dissolution in aqueous base

We describe here experiments aimed at probing the interfacial behavior of thin polymer films during dissolution. We have constructed and characterized a unique quartz-crystal microbalance dissolution rate monitor that allows changes in both oscillation frequency and resistance to be accurately recorded at high data rates during film dissolution. Depending on polymer structure and properties, the resistance to be accurately recorded at high data rates during film dissolution. Depending on polymer structure and properties, the resistance can remain nearly constant, or can undergo enormous fluctuations that are indicative of transient changes in mechanical properties of the polymer layer during the dissolution process. A theoretical description allows the measured resistance to be related to the structure and properties of the dissolving film. This QCM apparatus has been coupled with a custom high-speed visible reflectance spectrometer, and with an infrared spectrometer, to provide information on the structure of the dissolving film and its chemical composition. The dissolution and swelling of well-defined acrylic and alicyclic copolymers in aqueous base has been examined using these techniques.
The contributions of BMP4, positive guidance cues, and repulsive molecules to cutaneous nerve formation in the chick hindlimb.

Our previous surgical manipulations have shown that the target ectoderm is necessary for the initial formation of one of the major cutaneous nerves in the embryonic chick limb (Honig, M.G., Camilli, S.J., Xue, Q.S., 2004. Ectoderm removal prevents cutaneous nerve formation and perturbs sensory axon growth in the chick hindlimb. Dev. Biol. 266, 27–42.). Moreover, the target ectoderm is required during a critical time period, at ∼St. 24, when those axons are about to diverge from the hindlimb plexus. To elucidate the underlying mechanisms, here we examined the effects of removing the ectoderm at St. 24 on a variety of molecules expressed within the limb. We find that, while ectoderm removal is accompanied by changes in the expression of Lmx1, fibronectin, EphA7, cDermo-1, and in the complement of muscle cells, these changes do not account for the cutaneous nerve deficit. In contrast, an upregulation of PNA-binding sites and a downregulation of Bmp4 appear to be associated with this nerve deficit. Exogenous BMP4 reversed the effect of ectoderm removal on cutaneous nerve formation, but did not act as a chemoattractant. Our results suggest that BMP4, together with permissive and repulsive molecules that growing cutaneous axons encounter in the local environment and with signaling molecules, originating from and/or dependent on the ectoderm, work in concert to ensure proper cutaneous nerve formation.
Ab initio study of the composition dependence of the pressure-induced spin crossover in perovskite (Mg1 − x,Fex)SiO3

Abstract We present ab initio calculations of the zero-temperature iron high- to low-spin crossover in (Mg 1 − x Fe x )SiO 3 perovskite at pressures relevant to Earth's lower mantle. Equations of state are fit for a range of compositions and used to predict the Fe spin transition pressure and associated changes in volume and bulk modulus. We predict a dramatic decrease in transition pressure as Fe concentration increases. This trend is contrary to that seen in ferropericlase, and suggests the energetics for spin crossover is highly dependent on the structural environment of Fe. Both Local Density Approximation (LDA) and Generalized Gradient Approximation (GGA) exchange-correlation methods are used, and both methods reproduce the same compositional trends. However, GGA gives a significantly higher transition pressure than LDA. The spin transition is made easier by the decreasing spin-flip energy with pressure but is also driven by the change in volume from high to low spin. Volume trends show that high-spin Fe 2+ is larger than Mg 2+ even under pressure, but low-spin Fe 2+ is smaller at ambient conditions and approximately the same size as Mg 2+ under high pressure, indicating that low-spin Fe 2+ is less compressible than high-spin Fe 2+ . We find large changes between high- and low-spin in the slope of volume with Fe concentration. Although these changes are small in absolute magnitude for small Fe content, they are still important when measured per Fe and could be relevant for calculating partitioning coefficients in the lower mantle.
Perception by monkeys II. Use of cues at a distance by yourg and old monkeys

Fourteen rhesus monkeys and two human Os were trained to discriminate between identical blocks of wood placed 13 in apart, using cues that were provided by a pointer that was placed at random in positions spaced 1.0 in apart between the manipulanda. Monkeys made increasingly more errors as a function of increasing distance between the manipulandum and discriminandum, and extensive practice did not alter this relationship. The human Os, however, made no errors at positions of the pointer other than the center.
Analysis of quantum-wire MODFETs employing coupled well channels

Abstract A novel coupled well structure for implementing a quantum wire MODFET is proposedand analyzed. A thin barrier layer is placed adjacent to the standard modulation doped heterointerface, resulting in a coupled quantum well region. Varying the distance between the barrier and the interface provides a means of controlling the location anddistribution of the two-dimensional electron gas. Further confinement of the carriers toone- dimension is obtained by methods known in the literature, such as mesa etching and regrowth. It has been found that the peak of the electron distribution for the first confined state, as measured from the modulation doped interface, changes dramaticallydepending on the location of the thin barrier. The peak can be shifted as much as 45 A for a change in the barrier location of only 20 A. Implications of this are included in the charge control model, from which the current-voltage (Id-Vd, Id-Vg) and transconductance (gm-Vg) characteristics are obtained. Additionally, the frequency responses (fTVg) ofseveral variations of this device are presented.
Translating standards into practice

The value of standards for the representation, integration, and exchange of data, information, and knowledge across the spectrum of biomedicine and health care has been widely recognized for years. Recent initiatives further underscore the importance of standards (e.g., for certification and meaningful use of electronic health records) and establishment of systematic approaches for achieving semantic interoperability. There is accordingly a need for detailed, experience-based discussions pertaining to the adoption and implementation of the breadth of standards in biomedicine and health care. The goal of this special issue has been to provide a forum for describing advanced research and development in translating standards into practice. Each paper in this issue provides a comprehensive description of methodologies employed and challenges encountered during the process of implementing a specific standard or set of standards in a practical setting. The twenty-two papers (including one methodological review) represent a broad array of experiences with standards and are categorized into the following sections: (1) Terminology Standards, (2) Document Standards, (3) Decision Support Standards, (4) Standards-Based Infrastructure, and (5) Standards Adoption Processes.
Optical Design Considerations For Laser Fusion Reactors

The plan for the development of commercial inertial confinement fusion (ICE) power plants is discussed, emphasizing the utilization of the unique features of laser fusion to arrive at conceptual designs for reactors and optical systems which minimize the need for advanced materials and techniques requiring expensive test facilities. A conceptual design for a liquid lithium fall reactor is described which successfully deals with the hostile x-ray and neutron environment and promises to last the 30 year plant lifetime. Schemes for protecting the final focusing optics are described which are both compatible with this reactor system, and show promise of surviving a full year in order to minimize costly downtime. Damage mechanisms and protection techniques are discussed, and a recommendation is made for a high f-number metal mirror final focusing system.
The Worst Are Always the Worst: Why Congestion Threshold Speeds Do Not Matter as Decision-Making Input

The concept of a congestion threshold is embedded in the definition of "congestion." Two basic approaches exist in current practice for setting the congestion threshold. One common approach uses the free-flow or unimpeded conditions. Another approach uses a variety of targets or acceptable conditions. The limited research conducted on the congestion threshold issue has focused on operational problems or policy debates, but there has been relatively little investigation of the effect of the congestion threshold on decision making for transportation investment and resource allocation. This research investigated the differences that might be seen in the worst freeway rankings for several threshold choices by using detailed freeway data from seven metropolitan areas. Specifically, this research examined the ranking values of two congestion measures under a variety of real-world travel time distributions. The congestion performance measures of delay per mile and travel time index were evaluated; these measures...
Sexual Assault History and Health-Related Outcomes in a National Sample of Women

This study examined correlates of past-year chronic medical conditions and lifetime contact with health care professionals for mental health and substance abuse problems in women with differing his...
A rating procedure for solar domestic hot water systems based on ASHRAE-95 test results

A rating method for solar domestic hot water (SDHW) systems is presented that provides site-specific annual performance estimates based on ASHRAE-95 test results. An overall loss and overall gain coefficient are estimated by lumping the entire thermal behavior of the actual system exhibited during the ASHRAE-95 test into the collector parameters of a simplified system model. The performance of the simplified model can then be predicted using either the F-chart or TRNSYS and presented as an estimate of the annual performance of the actual system. Experimental performance measurements taken from relevant literature as well as extensive simulations, indicate that this method is capable of predicting the annual performance of a wide range of SDHW system types to within 5%, independent of location.