cssi/SciSciGPT-SciSciNet huggingface dataset:
On the prediction of ENSO: a study with a low-order Markov model

A linear model best fit to the Zebiak and Cane (1987) ENSO forecast model (ZC) is used to study the model's prediction skill. Multivariate empirical orthogonal functions (MEOFs) obtained from the sea surface temperature anomaly, sea level and wind stress anomaly fields in a suite of 3-year forecast runs of ZC starting from the monthly initial conditions in the period January 1970 to December 1991, are used to construct a series of seasonally varying linear Markov models. It is found that the model with 18 MEOFs fits the original nonlinear model reasonably well and has comparable or better forecast skill. Assimilating the observed SST into the initial conditions further improves forecast skill at short lead times (< 9 months). The transient initial error growth in the model's prediction is attributed to the non-self-adjoint property as in Farrell and Blumenthal. Initial error grows fastest starting from spring and slowest starting from late summer and is sensitive to the initial error structures. Two singular vectors (SVs) of the linear evolution operator have significant transient growth dominating the total error growth. Since the optimal perturbation (fastest SV) has mostly high MEOF components, the error growth tends to be larger when there are more high mode components in the initial error fields. This result suggests a way to filter the initial condition fields: the MEOFs higher than the 18th in the initial fields are mostly noise and removing them improves prediction skill. The forecasts starting from late summer have the best predictability because the fastest growth season (summer) is just avoided. The well known, very rapid decline in forecast skill in the boreal spring (the “spring barrier”) is here attributed to the smallness of the signal to be forecast: the standard deviation of the NIN03 SST anomaly is smallest in spring. DOI: 10.1034/j.1600-0870.1994.00013.x
40-Gb/s DPSK Data Transmission Through a Silicon Microring Switch

We experimentally demonstrate switching of a 40-Gb/s differential-phase-shift-keyed (DPSK) signal through a coupled silicon photonic microring switch. By simultaneously electro-optically biasing both microring cavities, we achieve 14-dB extinction ratio for signals egressing from both output ports of the switch. Packetized transmission of the 40-Gb/s DPSK signal is achieved with power penalties of 0.6 and 2.4 dB for through port and drop port signals, respectively. The effects of a coupled silicon microring are investigated, showing a broad bandwidth and a linear phase response for the drop port are necessary characteristics for routing 40-Gb/s data through the switch for photonic interconnection networks.
The Effect of Static, Dynamic, and Perceptual Measures of Minority Threat on Fear of Crime

Research on the fear of crime has focused on a variety of possible causes, including prior victimization, media consumption, and racial threat. However, little research has examined the sources of crime fear for separate racial/ethnic groups. The present study addresses this limitation by assessing fear of crime among diverse racial/ethnic groups utilizing multiple indicators of minority threat. Using data from the Houston Area Survey, this study assesses the effect of static measures of threat (the size of a minority population at 1 point in time), dynamic measures of threat (the change in the size of a minority population), and perceptual measures of the size of a minority population. Results indicate that, overall, the relationship between threat and fear of crime varies based on the sample used and the type of threat assessed (racial or ethnic). Theoretical implications and prospects for future research on fear of crime and the minority threat perspective are also discussed.
Marrow Chimerism in Marmosets

In the femoral marrow of three adult marmosets, two male Callithrix jacchus and one female Leontocebus rosalia, a number of opposite-sexed metaphases were found. It is inferred that this chimeric state resulted from intrauterine placental anastomoses between heterosexual twins. The lack of the freemartin effect in connection with this chimerism is discussed, and the structural nature of the Y chromosome in the Callithricidae is described.
The Impact of an Engineering Design Curriculum on Science Reasoning in an Urban Setting

This study examines the use of engineering design to facilitate science reasoning in high-needs, urban classrooms. The Design for Science unit utilizes scaffolds consistent with reform science instruction to assist students in constructing a design solution to satisfy a need from their everyday lives. This provides a meaningful context in which students could reason scientifically. Eighth grade students from two urban schools participated in the unit. Both schools contained large percentages of racial/ethnic minority and economically disadvantaged students. Students demonstrated statistically significant improvement on a paper-and-pencil, multiple-choice pre and post assessment. The results compare favorably with both a high-quality inquiry science unit and a traditional textbook curriculum. Implications for the use of design-based curricula as a viable alternative for teaching science reasoning in high-needs, urban settings are discussed.
The 65,000-Kv-a. Generator of the Niagara Falls Power Company

The initial hydroelectric development of the Niagara Falls Power Company is referred to and comparisons are made with the latest development, which involves three units, each with a 65,000-kv-a. generator. The amount of material in a generator as affected by speed, periodicity and efficiency aimed at, is discussed. The electrical characteristics of the first of the 65,000-kv-a. generators are outlined. The mechanical construction is described in considerable detail with the aid of cross-sectional views of certain parts and of the generator as a whole. A special feature of this unit is a direct-connected 650-kv-a., 25-cycle generator for furnishing excitation through a motor-generator set and for driving auxiliaries, such as pumps. Some weight data are added, showing this generator to contain over one and one-half million pounds of material?undoubtedly the heaviest electrical machine ever built.
Innovation and entrepreneurial behaviour in the Popular Music industry

ABSTRACTIn a creative industry, what pattern of artistic influences increases the likelihood that an artist will produce innovative products? This research examines all major artists in popular music between 1950 and 2008, their unique historic network of artistic influences, and their innovation achievements in the Popular Music Industry. The research applies network analysis to the social structure of the industry to see: do artists who create innovative products occupy unique structural positions in the complete network of artistic influences (1950–2008)? We posit and find evidence that artists with structural holes in their influence networks have access to unique resources from which to fashion new innovative products.
Unsteady flow in a supersonic cascade with strong in-passage shocks

A model for a supersonic blade row with two in-passage shock waves is developed. It accounts for three-dimensional effects in real flows by using an altered blade shape in a two-dimensional cascade. There is enough flexibility in the choice of blade shape to accommodate a desired entrance angle, exit angle, boundary-layer thickness and stage pressure ratio at a given entrance Mach number. The model divides the mean flow into regions of uniform or one-dimensional flow in which the solutions for the unsteady flow may be formed successively. The analysis makes use of previous solutions for unsteady flow in cascades and over an oscillation wedge. Six flow conditions are chosen in the range of parameters for which the two-shock model is valid for studies of flutter in torsion and bending. It is found, in keeping with previous results from a single-shock model, that in each case there is increasing instability with decreasing frequency.
ATOMISTIC SIMULATIONS OF DIFFUSIONAL CREEP IN A NANOCRYSTALLINE BODY-CENTERED CUBIC MATERIAL

Molecular dynamics (MD) simulations are used to study diffusion-accommodated creep deformation in nanocrystalline molybdenum, a body-centered cubic metal. In our simulations, the microstructures are subjected to constant-stress loading at levels below the dislocation nucleation threshold and at high temperatures (i.e., T > 0.75Tmelt), thereby ensuring that the overall deformation is indeed attributable to atomic self-diffusion. The initial microstructures were designed to consist of hexagonally shaped columnar grains bounded by high-energy asymmetric tilt grain boundaries (GBs). Remarkably the creep rates, which exhibit a double-exponential dependence on temperature and a double power-law dependence on grain size, indicate that both GB diffusion in the form of Coble creep and lattice diffusion in the form of Nabarro–Herring creep contribute to the overall deformation. For the first time in an MD simulation, we observe the formation and emission of vacancies from high-angle GBs into the grain interiors, thus enabling bulk diffusion.
The reversal of amphetamine-induced locomotor activation by a selective neurotensin-1 receptor agonist does not exhibit tolerance

Neurotensin-1 (NT1) receptor agonists have been proposed as putative antipsychotic drugs. Recently, brain-penetrating NT analogs produced by stability-enhancing modification of the smallest NT fragment, NT(8–13), have demonstrated antipsychotic-like efficacy after acute systemic injection in several preclinical animal tests predictive for antipsychotic efficacy. However, the evidence regarding the persistence versus tolerance of these effects after repeated administration is ambiguous. Previous studies have used compounds that nonselectively activated both NT1 and NT2 receptors or used continuous slow, central infusion of doses rather than daily acute administration, both factors which may have contributed to the ambiguity in the literature regarding the emergence of tolerance. To determine if tolerance develops to the antipsychotic-like effects of NT1 receptor agonists, we investigated the effects of subchronic daily systemic administration of PD149163, a brain-penetrating NT analog with selectivity for the NT1 receptor, on amphetamine-induced locomotor activation, a classic preclinical test of antipsychotic efficacy. Sprague–Dawley rats were pretreated with eight consecutive daily subcutaneous (SC) injections of PD149163 or saline. On the ninth day, rats received a pair of SC injections consisting of PD149163 or saline, followed by amphetamine (0.5 mg/kg) or saline. Locomotor activity was then measured in photobeam-equipped cages. The results indicated that repeated daily administration of PD149163 was able to antagonize amphetamine’s locomotor-activating effect comparable to that of the first dose, despite that repeated administration of PD149163 produced an increase in baseline locomotor activity not seen after the first dose. The results do not support the development of tolerance for the acute antipsychotic-like effect of NT1 agonists and thus lend support to the contention that NT1 agonists are viable candidates as putative novel antipsychotic drugs.
Modulation of glucocorticoid receptors by mitogenic stimuli, glucocorticoids and retinoids in normal human cultured T cells

Abstract Human T lymphocytes can be maintained in cell culture by the addition of conditioned medium (CM) containing a T cell growth factor (TCGF). This system provides an opportunity to study the presence and modulation of glucocorticoid receptors (GR) by various factors in these cells. GR were present in T cells grown from each of 22 normal individuals; the binding capacity ( X = 3851 ± 2880 sites/cell) and affinity ( K d = 7.4 × 10 −9 ) were similar in rested cultured T cells (CTC) to those reported in peripheral blood T lymphocytes. Treatment of rested CTC with stimuli such as phytohemagglutinin (PHA), CM, or 12- O -tetradecanoylphorbol-13-acetate (TPA) results in a mean increase in GR binding capacity of 3.1-, 3.2- or 2.4-fold respectively without modification of binding affinity. Using an exchange assay to measure occupied and unoccupied GR, we examined the effects of Cortisol on its own receptor. Treatment of rested CTC with 10 −7 M cortisol for 24 h decreased GR by more than 50%. Cortisol treatment also blocked the induction of GR by PHA and CM. Since retinoids have been shown to modulate the immune response and to alter the effects of PHA and phorbol esters on lymphocytes, we examined their effects on GR. Retinol decreased GR activity in CTC but only at concentrations which inhibit cell growth. It is concluded that GR activity in human T cells can be modulated by several important factors involved in lymphocyte function.
Tuning into others’ voices: radical listening, learning from difference, and escaping oppression

Over my 35 years of being a teacher, professor, speaker, cultural worker, and researcher, I’ve been asked many times: ‘‘where did you come up with the perspective on schools or media that you used in your article or speech—I’ve never heard such a point of view before?’’ Oftentimes my answer involves telling the inquisitor that I simply listened to people who had been deemed failures by the larger society or by the schools they attended. Such individuals, I have learned over the years, often possess some of the most compelling insights into what is actually happening, into how people are seriously harmed by institutions ostensibly constructed to help them improve their lives. Such an emphasis on the power of difference, on gaining new perspectives from individuals who come from a different locale in the social web of reality is central to my purpose here. This power of difference—or as Paulo Freire (1997) articulated it, ‘‘a viable novelty’’—is key to an ever-expanding sense of criticality. This evolving criticality is dedicated to a neverending search for new ways of seeing, for new social and cultural experiences that provide novel concepts that we can use to better understand the world in a progressive way. (Kincheloe 2008, p. viii)
Low-temperature 9Be spin relaxation in superconducting UBe13

Abstract The dependence of the 9 Be spin-lattice relaxation rate 1/ T 1 on magnetic field has been measured in the heavy-fermion superconductor UBe 13 at temperatures well below T c . A crossover between relaxation via spin diffusion to mixed-state vortex cores ( H > 6 kOe) and to paramagnetic impurities ( H
Hydrocarbon composition of the integument, fat body, hemolymph and diet of the tobacco hornworm.

Abstract Gas-liquid chromatographic analysis of the hydrocarbon fraction of the integument, fat body, and hemolymph of the tobacco hornworm, Manduca sexta (Johannson), showed that the major hydrocarbons were both straight and branched alkanes. Heptacosane (9.8%) was the major n -alkane in the integument, and pentacosane was the major n -alkane in the fat body and hemolymph, 9.7 and 4.2%, respectively. The major n -alkane in the diet was nonacosane (17.5%). Branched alkanes, mono-, di-, and trimethylpentatriacontanes, with equivalent chain lengths between 35 and 36 made up 7.6% of the integument, 17.9% of the fat body, and 34.2% of the hemolymph hydrocarbons; branched alkanes, probably mono-, di-, and trimethylheptatriacontanes, with equivalent chain lengths between 37 and 38 made up 7.4% of the integument, 18.2% of the fat body, and 25.4% of the hemolymph hydrocarbons. The absence of these branched alkanes from the diet indicated that the tobacco hornworm must be capable of the biosynthesis of these branched hydrocarbons.
Models and techniques for the visualization of labeled discrete objects

The objective of visualization is to extract useful and relevant information from raw data and present it so that it can be easily understood and assimilated by humans. We propose a general model for the visualization of labeled discrete objects. (Examples of labeled discrete objects are strings, circular strings, trees, graphs, etc.) Our model is based on identifying similar subobjects in an object and coding them visually. This is demonstrated by applying the model to linear and circular strings, binary trees, and series-parallel graphs. We also describe and classify the problem of display conflicts that is associated with this visualization model and suggest methods to overcome it. We extend the csdawg data structure for linear strings to circular strings. Efficient, often optimal, algorithms to implement the visualization model for linear and circular strings, binary trees, and series-parallel graphs are also developed. These algorithms are specifically designed to utilize the inheritance and data abstraction features of the object-oriented paradigm. Several of these algorithms were implemented in C++ to evaluate their performance. We also propose a blueprint for a visualization system based on our visualization model. Applications of this visualization technique arise in areas such as molecular biology, computer vision, computer graphics, CAD VLSI, data compression, algorithm animation, and debuggers.
Life Goals and General Well-Being

Meaning, purpose and major goals in people's lives have been purported to relate to well-being and health. To begin study of the relations among these variables, a group of 115 college students was divided into subgroups scoring high and low on general well-being, and differences in their life-goal orientation were estimated using the Life Esteem Survey questionnaire. Three life-goal components were significantly different for the subgroups: recognition of a framework of purpose, perspective of progress, and commitment to a framework. A fourth component, quality of life goals, was not significantly different. A comprehensive set of 22 possible life goals significantly discriminated among the subgroups; however, on only one, excitement, were differences significant. The only significant interaction between sex and well-being also held for the value placed on the goal of excitement. A tendency was shown for the value placed on more hedonistically oriented goals to differentiate the subgroups with the group ...
The Transatlantic Climate Change Challenge

Europe and the United States are addressing climate change at different speeds and in different ways, but the transatlantic landscape on this issue is changing. Can they come together quickly enough to help forge a framework to replace the Kyoto Protocol before it expires in 2012?
CALCIUM AND INORGANIC PHOSPHORUS IN THE BLOOD OF RABBITS : III. PERIODIC AND PROGRESSIVE VARIATIONS IN NORMAL RABBITS.

Determinations of calcium and inorganic phosphorus were made on the blood of 5 groups of normal animals over periods of 4 to 8 months. The material included animals from recently acquired stocks as well as animals that had been living under laboratory conditions for long periods of time. The results were analyzed with especial reference to the occurrence of periodic and progressive variations in the absolute amounts of calcium and inorganic phosphorus and the relations between the two substances. It was found that, among animals living in the laboratory, both calcium and inorganic phosphorus, as well as all expressions of the equilibrium between the two substances, exhibited a definite tendency to a progressive increase or decrease) as the case might be, and that clearly defined periodic variations occurred in all classes of animals. The progressive change was most marked in the case of inorganic phosphorus, the periodic change in the case of calcium, while both conditions were dearly shown by various expressions of the relation between calcium and inorganic phosphorus.
Ratio of Cesium-137 and Strontium-90 Radioactivity in Soil

The similarity in genesis and the more pertinent physical characteristics of fission-produced Cs137 and Sr90 suggests the use of the first as a convenient monitor for the other prior to uptake in the biosphere. Results are presented which indicate the feasibility of this approach in the case of soils.
Gear oil formulation designed to meet bio-preferred criteria as well as give high performance

A bio-based gear oil was developed from soybean oil (SBO). The SBO was first thermally polymerised and then mixed with additives and diluents. The effect of pour point depressants, co-base oils, antioxidants and anti-wear additives is reported. Lubricity, viscosity index and oxidation stability of the final formulation of the bio-based gear oil are compared with commercially available gear oils. The final formulation of bio-based gear oil gives test results: viscosity index 165, four-ball wear scar 0.375 mm. These numbers are comparable to or better than the commercially available gear oils tested for comparison. The oxidation onset temperature of the bio-based gear oil, 220°C, is lower than the evaluated commercial products, but still at an acceptable range for gear oil.
Neuromuscular responses to pyridostigmine bromide in organotypic spinal cord-muscle culture

Pyridostigmine bromide (PB) promotes and then silences cholinergic muscle activity, and disrupts the junctional regions of muscle fibers and associated nerve terminals, in organotypic mouse spinal cord-muscle cultures continuously treated with low concentrations of the drug for up to 14 days. Spontaneous muscle activity is restored within 1 week of drug removal.
Determination of formal potentials and anion radical lifetimes for hexaarylbiimidazole derivatives

Abstract The reduction of three hexaarylbiimidazole (HABl or L2) derivatives has been studied in acetonitrile by means of cyclic voltammetry. The reduction of o-Cl-HABl has previously been shown to occur by an ECE process. The radical anion initially formed in the first electron transfer (L2−) undergoes a fast cleavage reaction to produce the triarylimidazole anion (L−) and the radical (L−, the latter of which is reduced at the electrode to produce a second anion. The two other HABI derivatives investigated in this study show similar behavior. Homogeneous redox catalysis was used to determine the formal potential (E10) for the L2/L2− couple for each of the three HABIs and the rate constant of the cleavage reaction for o-Cl-HABI (kf = (5.6 ± 1.0) × 106s−1). The values of E10 were found to be −1.85 ± 0.01 V vs. the ferrocene/ferrocenium formal potential for o-Cl-HABI and TCTM-HABI, and −2.01 V for o-EtO-HABI. Cyclic voltammetry was also used to determine the formal potential for the L/L− couple, E20, and the rate constant, kdim, for dimerization of the imidazolyl radicals. The results for E20are −0.15, −0.27 and −0.15 V vs. ferrocene and kdimis 1.1 × 104, 4.5 × 103and 4.2 × 103M−1s−1for o-Cl-HABI, o-EtO-HABI and TCTM-HABI, respectively.
Physiological Nystagmus in the Cat

Cats were prepared by the encephale isole technique. A small plane-mirror mount was sutured to each cornea without obstructing vision, and eye movements were recorded using the optical-lever method. The records showed physiological nystagmus similar to that in man, although the cats had fewer and smaller saccades. Some saccades were binocular, but usually they were uniocular. The fine tremor varied in frequency from 35–65 cps, averaging 50 cps, and in amplitude from 4–52 sec of arc, averaging 22 sec. Curare decreased and ultimately abolished eye movements and physiological nystagmus, whereas neostigmine increased them. Physiological nystagmus is therefore mediated by efferent neural stimulation of the eye muscles. Tremor was also recorded from the detached inferior oblique muscle, as well as from the eyeball with most of the extraocular muscles detached. Fine tremor was also found in finger pointing in man. The significance of physiological nystagmus to vision is briefly discussed.
Lattice QCD, the quark model, and heavy-light wavefunctions

Abstract A multistate smearing method previously introduced allows a detailed study of the properties of heavy-light mesons in lattice QCD. The Coulomb gauge wave functions for the ground state, the first radially excited S-wave state, and the lowest P-wave states of a heavy-light meson are calculated in quenched approximation. The results are found to be in remarkably good agreement with the predictions of a simple relativistic quark model.
Postmenopausal estrogen and estrogen-progestin use and 2-year rate of cognitive change in a cohort of older Japanese American women: The Kame Project.

Background The relation between estrogen and cognition among postmenopausal women remains controversial. Also uncertain is whether the proposed association varies between women taking unopposed estrogen and those taking estrogen combined with progestin. Objective To determine whether unopposed estrogen and combined estrogen-progestin use were associated with the rate of cognitive change in a cohort of older, Japanese American, postmenopausal women. Methods A prospective observational study in a population-based cohort of older Japanese Americans (aged > or =65 years) living in King County, Washington. Cognitive performance was measured in 837 women at baseline (1992-1994) and 2-year follow-up (1994-1997) examinations using the 100-point Cognitive Abilities Screening Instrument (CASI). Least squares means general linear models were used to estimate the 2-year rate of cognitive change according to categories of postmenopausal estrogen use. Results Approximately half of this cohort (n=455) had never used estrogen at any time since menopause, 186 were past users, 132 were current unopposed estrogen users, and 64 were current estrogen-progestin users. The majority of current estrogen users were taking conjugated estrogens, and all women receiving combined therapy were taking medroxyprogesterone acetate. After adjusting for age, education, language spoken at the interview, surgical menopause, and baseline CASI score, women who had never used postmenopausal estrogen improved slightly on the CASI scale (mean adjusted change, 0.79; SEM, 0.19). This change was significantly greater for current unopposed estrogen users (mean adjusted change, 1.68; SEM, 0.36; P=.04) and significantly worse for current estrogen-progestin users (mean adjusted change, -0.41; SEM, 0.50; P =.02) compared with never users. The improvement observed in past users (mean adjusted change, 1.12; SEM, 0.29) was intermediate between the changes for never users and current unopposed estrogen users and not significantly greater than that for never users (P=.35). Conclusions Our findings support a modest beneficial association between current unopposed estrogen use and the rate of cognitive change. We also observed a modest detrimental association between current estrogen-progestin use and the rate of cognitive change. The clinical significance of these modest differences, however, is uncertain. Data from large, long-term randomized trials are required before applying this information to the clinical setting.
A density functional study of carbon monoxide adsorption on (1 0 0) surface of γ-uranium

Abstract Adsorption of carbon monoxide on γ-U(1 0 0) surface has been studied at both non-spin-polarized and spin-polarized levels using the generalized gradient approximation of density functional theory (GGA-DFT) with Perdew and Wang (PW) functionals. For CO adsorption, the bridge position of (1 0 0) surface with Vert2 approach is found to be the most favorable site with a chemisorption energy of 2.9315 eV for the non-spin-polarized case, and 3.1875 eV for the spin-polarized case. The distances of the lower carbon atom from the uranium surface are found to be 1.589 A and 1.716 A for non-spin-polarized and spin-polarized cases, respectively. The distances between the carbon and oxygen atoms for this most favorable position are found to be 1.134 A and 1.208 A for the non-spin-polarized and spin-polarized cases, respectively. The magnetic moment for the most favorable site is found to be 0.042μB per atom. A significant charge transfer from the first layer of the uranium surface to the carbon and oxygen atoms is found to occur, implying that the bonding is partly ionic. CO 2p orbitals are found to hybridize with U 5f bands resulting in more localization of the U 5f electrons. Spin polarization does increase the chemisorption energies by a small factor but does not play a significant role in the overall chemisorption process. Overall pattern of the density of states does not change significantly after the adsorption of CO on uranium layers. Also, in none of the cases studied, dissociation of CO molecule was possible for any of the approaches in any of the sites at the non-spin-polarized and spin-polarized levels of theory. This appears to contradict experimental results where CO adsorbed dissociatively on U surface. However, experimental data is for polycrystalline α-U at finite temperatures, whereas our present ab initio study refers to γ-U at 0 K.
Statistical mechanics of noncovalent bonds in polyamino acids. VIII. Covalent loops in proteins

The effect of covalently crosslinked loops on the entropy of polypeptide chains is discussed. Since the available theory applies to single, independent loops, this theory has been extended to cases where the chains are multiply crosslinked and, therefore, dependent. Multiply crosslinked loops are present in many proteins, e.g., ribonuclease. It is shown that, whereas in general there is a significant difference between the entropy computed with the present treatment of dependent chains and that incorrectly computed by applying the theory of independent chains to multiply crosslinked loops, the difference in the two procedures is not very great for ribonuclease (and well within the uncertainty of our knowledge of the residue conformational entropy) because the chains of ribonuclease are only slightly dependent even though they are multiply crosslinked. Specifically, estimates of the entropy losses per residue are: −0.45 e.u. for chains in a single, independent loop, −0.58 to −0.66 e.u. for dependent chains in multiply crosslinked loops, and −0.51 e.u. for a simplified model of ribonuclease. With this information, a treatment is given of a helix–coil transition in two chains, assumed to be polyglycine, connected at each end by disulfide bonds. The results of a previous theory for short chains are combined here with the results for the entropy loss on loop formation. It is seen that the presence of the loop stabilizes the helical forms (because of the lowering of the entropy of the random state) and broadens the transition (because of the increased importance of intermediate states).
Cyclic hemiacetal and acyclic chain ― the two forms of serricornin

Abstract The actual structures of the four stereoisomers of serricornin were examined by the X-ray analysis and high-field pmr spectroscopy. Each of the stereoisomers assumes either or both of two forms, cyclic hemiacetal and acyclic chain, in solution.
Blastocyst oestrogen: an essential factor for the control of implantation.

Abstract A new hypothesis is proposed concerning the hormonal control of blastocyst implantation. In preparation for implantation, the uterus has first to come under the dominance of progesterone, derived from the ovaries. As the time of implantation approaches, a distinction is made between the conditioning of the prospective implantation sites and the remainder of the uterus. While progesterone-dominance has to be maintained in the interimplantation areas, the implantation sites have to be relieved temporarily from the dominance of this hormone (an anti-inflammatory agent), in order to permit a local inflammatory-like reaction which is a prerequisite for implantation. The local relief from progesteronedominance is accomplished through the action of oestrogen released by the blastocyst. In some species, like rat and mouse, blastocyst oestrogen by itself is inadequate to overcome the progesteronedominance. Therefore, the action of systemic oestrogen (the “oestrogen surge”) has to precede the action of blastocyst oestrogen.
Simulations of chaperone-assisted folding.

We investigated a chaperone mechanism of protein folding using a 36-mer model on a cubic lattice. The mechanism simulates folding, which proceeds with repetitive cycles of binding, unfolding, and releasing of misfolded metastable states. We measured the yield enhancement due to this mechanism for sequences selected by evolutionary design and showed that the binding and releasing mechanism is efficient for the yield enhancement of folding for sequences that are poorly designed, i.e., where selection is not adequately strong. From this it follows that the chaperone mechanism can be considered as the evolutionary alternative to compensate for poor sequence design. On the other hand, random sequences show a decrease in yield and no effect on the total mean first passage time when the proposed chaperone mechanism is implemented, thus implying that sequence optimization is a necessary condition for the efficiency of the proposed mechanism. We qualitatively reproduced experimental results for folding in the pres...
Optimum cyclic redundancy codes for noisy channels (Corresp.)

Binary cyclic redundancy codes for feedback communication over noisy digital links are considered. The standard 16-bit ADCCPt polynomial is designed for digital links that already have a low input bit error probability. For file transfer between personal computers over telephone circuits, the quality of the resulting digital circuit may be much lower. This leads to the consideration of 3-byte (24-bit) and 4-byte (32-bit) polynomials. Generator polynomials of a certain class are found that have minimum weight and yet achieve the bound on minimum distance for arbitrary codes. Particular polynomials for 24-bit and 32-bit redundancies are exhibited, of weight and distance 6 in the 24-bit case and weight 10 and distance 8 in the 32-bit case.
Negative-Pressure Wound Therapy and Diabetic Foot Amputations A Retrospective Study of Payer Claims Data

Background: This study was undertaken to assess the benefits of negative-pressure wound therapy (NPWT) versus traditional wound therapies in reducing the incidence of lower-extremity amputations in patients with diabetic foot ulcers. Methods: Administrative claims data for patients with diabetic foot ulcers from commercial payers (n = 3,524) and Medicare (n = 12,795) were retrospectively analyzed. Patients were divided into NPWT and control/traditional therapy groups on the basis of administrative codes. Risk-adjustment procedures were then performed to match patient risk categories (through total treatment costs) and wound severities (through debridement depth). Results: The incidence of amputations in the NPWT groups was lower than that in the control groups. For the cost-based risk-adjustment analysis, amputation incidences with NPWT versus traditional therapy were 35% lower in the Medicare sample (10.8% versus 16.6%; P = .0077) and 34% lower in the commercial payer sample (14.1% versus 21.4%; P = .095...
Evaluation of responses to chemoembolization in patients with unresectable hepatocellular carcinoma

BACKGROUND The authors used computed tomography (CT) scans to correlate the changes in tumor vascularity, necrosis, and size with response and survival after transcatheter arterial chemoembolization (TACE) in patients with advanced, unresectable, hepatocellular carcinoma (HCC). METHODS The authors studied 72 patients with biopsy-proven, unresectable HCC and focused on 186 individual tumor masses. A baseline, multiphase, helical CT was performed and at least three follow-up CT scans were performed after treatment by TACE. Tumors were classified as hypervascular or hypovascular and patients were classified as responders or nonresponders based on CT evidence of altered tumor size, tumor necrosis, and the appearance of new tumors. A new scoring system was used to monitor patient response to TACE. RESULTS Thirty-eight patients were responders and 34 were nonresponders. Patient survival was significantly increased (P = 0.009) in patients who were hypervascular responders. Survival also was increased in hypervascular nonresponders compared with hypovascular nonresponders (P = 0.008) and in hypovascular responders compared with hypovascular nonresponders (P = 0.002). Response to chemoembolization was found to be significantly (P = 0.02) and inversely proportional to tumor size, but the number of tumor foci in an individual patient was not predictive. CONCLUSIONS TACE appears to result in improved survival among HCC patients with hypervascular tumors who responded to therapy. However, even patients classified by CT as hypervascular nonresponders and hypovascular responders have improved survival. Cancer 2003;97:1042–50. © 2003 American Cancer Society. DOI 10.1002/cncr.11111
Principles for robotic mobility on minor solar system bodies

Abstract For the coming years, a number of planetary missions to small solar system bodies such as asteroids and comets are being planned or already under development. Most of these projects aim at a fly-by or a rendezvous with the target object. Inevitably, landing missions to small bodies will follow the first one being MUSES-C of ISAS which is to return a sample from the Near Earth Asteroid 4660 Nereus . Within Europe, ESA has selected the comet nucleus rendezvous mission ROSETTA, including a small lander, as Cornerstone 3 of its scientific program Horizon 2000. Eventually, missions will evolve which feature mobile robotic vehicles being able to traverse across the surface of an asteroid or comet nucleus, enabling scientific and technological investigations at a number of sites on the surface. This paper outlines the significant differences of mobility on small bodies as compared to larger planetary objects such as the Moon, Mars, or Mercury and presents approaches for mobility on small bodies, based on the principle of ballistic flight in the weak gravitational field. Finally, critical technology issues related to such free-flying mobile vehicles are discussed.
Dental variation in the molars of Mammuthus columbi var. M. imperator (Proboscidea, Elephantidae) from a Mathis gravel quarry, southern Texas

Abstract A large sample ( N = 149 ) of Mammuthus columbi molars was excavated from a gravel quarry of Rancholabrean North American Land Mammal Age (NALMA) near Mathis, San Patricio County in southern Texas. This attritional assemblage, which also includes Xenarthra, Equidae, Camelidae, Cervidae, and Bovidae, was recovered from fluvial point-bar deposits. Standard mammoth dental measurements and metrics (enamel thickness, plate width, plate number, and lamellar frequency) from a minimum of 25 individuals vary widely. The number of plates in the tooth (PN) is the most reliable measurement in the identification of the molar to the species level. Enamel thickness and lamellar frequency suggest that the Mathis sample represents a local population of Mammuthus columbi that approaches molar morphologies found in Irvingtonian NALMA populations usually placed in M. imperator.
Control Systems Take-Home Experiments [Focus on Education]

Most electrical and mechanical engineering curricula include courses in controls and mechatronics, with mechanical engineering curricula also including system dynamics and vibrations courses. The laboratory component for these courses is often limited and involves using a limited number of experimental setups. At many institutions, the laboratories associated with these courses are not taken in the same semester, preventing students from practicing the concepts learned in the lecture in a timely manner. Even in laboratory courses that are offered in the same semester as the lecture courses, in many cases it is not possible to synchronize the concepts covered in the lecture with the laboratory exercises since there are usually only a few lab setups for each experiment.
Simultaneous triggering of protein activity and fluorescence.

Many areas of biology can benefit greatly from methods to spatially and temporally control protein activity. Here, we describe an approach that allows the simultaneous photo-triggering of the activity and the fluorescence of a protein. Smad2, a protein central to the transforming growth factor-β (TGF-β) signal transduction pathway, was modified with a fluorophore and a photocleavable moiety that acted as both a caging and a fluorescence quenching group. In its caged state, the protein formed a non-fluorescent heterodimer with the protein SARA. Irradiation with UV light and photocleavage of the caging group produced a fluorescent homotrimer. These in vitro experiments demonstrated that a photochemical trigger mimicking the critical biochemical event of serine phosphorylation involved in the TGF-β signaling pathway could be obtained and that fluorescence could be used as a read-out of protein activity. This approach should prove particularly useful for the monitoring of a protein's activity and location ins...
High Water Vapor Flux Membranes Based on Novel Diol−Imidazolium Polymers

A breathable membrane that demonstrates high water vapor flux was prepared using a diol-functionalized polymerizable room temperature ionic liquid. A novel monomer material was synthesized and used to fabricate thin films which were tested for their ability to transport water vapor. These materials were tested beside commercial breathable polymers for comparison.
Reactivity of heat-treated coals in hydrogen

Abstract Reactivities of eighteen 40 × 100 mesh U.S. coals charred to 1000 °C have been measured in H2 at 2.7 MPa and 980 °C. The char-hydrogen reaction usually occurs in two stages: a slow induction period followed by a constant-rate region. Reactivities of various chars in the initial stage (Ri) decrease, in general, with increasing carbon content of the parent coals, whereas reactivities in the constant-rate region (Rc) are essentially independent of the rank of the parent coals. Reactivities of chars in H2 differ markedly from those in air and CO2. Results of surface-area measurements of chars and activation energies for the hydrogasification reaction suggest that during the induction period the reaction is diffusion-controlled whereas in the constant-rate region it is chemically controlled. Upon removal of mineral matter, Ri values generally decrease but Rc values show a random variation. Removal of mineral matter from coals prior to their carbonization brings about profound changes in surface area and porosity of chars. The effect of char particle size on reactivity is considered.
Neighborhood and Politics: Irish Ethnicity in Nineteenth Century Lowell, Massachusetts

In recent years social theorists have begun to assert the important influence of space on social ideas and practices. This paper examines some of these assertions about space and society through a case study. In addressing the theoretical importance of space to American political practices, this study draws attention to how spatial form and content contributed to the development of political consciousness among nineteenth century Irish in Lowell, Massachusetts. After establishng the existence of spatially discrete Irish neighborhoods, I examine the importance of Irish voluntary associations to ethnic solidarity and the ethnic negotiation of the wider, non-Irish society in Lowell. The case study shows that the institutions of Irish ethnicity as fostered and maintained in the Irish neighborhoods were a significant influence on the actual strategies the Irish developed to wage their political struggles. Finally, I argue that political behavior is geographically rooted and the social context of the ethnic neighborhood was crucial in defining the approach used by the Irish to challenge the contradictions of industrial capitalism as they occurred in Lowell.
A review of opioid overdose prevention and naloxone prescribing: implications for translating community programming into clinical practice

ABSTRACT. Background: As physicians have increased opioid prescribing, overdose deaths from pharmaceutical opioids have substantially increased in the United States. Naloxone hydrochloride (naloxone), an opioid antagonist, is the standard of care for treatment of opioid induced respiratory depression. Since 1996, community-based programs have offered overdose prevention education and distributed naloxone for bystander administration to people who use opioids, particularly heroin. There is growing interest in translating overdose education and naloxone distribution (OEND) into conventional medical settings for patients who are prescribed pharmaceutical opioids. For this review, we summarized and classified existing publications on overdose education and naloxone distribution to identify evidence of effectiveness and opportunities for translation into conventional medical settings. Methods: For this review, we searched English language PubMed for articles on naloxone based on primary data collection from hu...
Institutional affiliation of contributors to the American Economic Review, 1981–1990

In this article the author examines the institutional origin of authors in theAmerican Economic Review between 1981–90. Institutions are categorized into four broad groups, and rankings of institutions based on the number of pages/articles in theAER are developed. A high correlation is noted between the rankings in this paper and previous similar attempts. The main contribution of this study lies in its updating of earlier work.
Selective Versus Unselective Romantic Desire: Not All Reciprocity Is Created Equal

It is well established in nonromantic contexts that people tend to like individuals who like them (Kenny, 1994); in fact, such reciprocity of liking emerges even when individuals first meet for only a few minutes (Chapdelaine, Kenny, & LaFontana, 1994). Textbooks and common psychological lore frequently extend these findings to romantic liking, but the validity of this extension is unclear. When asked to recall a falling-in-love experience, individuals often report learning of another person's affection shortly before developing passionate feelings in return (Aron, Dutton, Aron, & Iverson, 1989). Nevertheless, such retrospections can be misleading. Moreover, the opposite hypothesis that potential romantic partners who play "hard to get" are desirable and individuals who demonstrate unconcealed romantic interest seem desperate and unappealing is also plausible (for discussion, see Walster, Walster, Piliavin, & Schmidt, 1973). One useful perspective on reciprocal liking derives from Kenny's social relations model (Kenny, 1994; Kenny & Nasby, 1980). This model distinguishes between two statistically independent correlational indicators of reciprocity: dyadic, which refers to liking that is shared uniquely between two individuals, and generalized, which refers to the tendency for people who generally like others to be liked themselves. Although correlations of nonromantic liking ratings demonstrate both positive dyadic and positive generalized reciprocity (Kenny, 1994), we hypothesized that romantic reciprocity would prove more nuanced. In a romantic setting, the dyadic-reciprocity correlation should remain positive, but the generalized-reciprocity correlation is likely to be negative. Although someone might indeed be likeable if he or she were to demonstrate platonic liking for many other people (Folkes & Sears, 1977), demonstrating romantic liking for many others could convey unselectivity and even desperation. Therefore, if expressing romantic desire emerges as a generalized tendency rather than a unique response to a particular individual, it may be antieffective at inducing ano her person's desire.