cssi/SciSciGPT-SciSciNet huggingface dataset:
The adsorption of CO on the (100) plane of tungsten; thermal and work function measurements

Abstract Thermal desorption and work function measurements indicate that a largely molecular layer, with some dissociation, is formed at 80–100 K, with an increase in work function of 0.55 eV. The coverage in this layer is 11.5 × 1014 molecules/cm2, or CO/W = 1.15. On heating, equal amounts of a β precursor, possibly dissociated, and a molecular α species are formed at ≈300 K, with abundances of 5 × 1014 molecules/cm2 each. The α desorption is complete at 360 K. The β precursor evolves on heating without desorption in the range 400–700 K as indicated by work function decreases, to β-CO, which is almost certainly dissociated. This change occurs at lower temperatures for low coverages. Thermal desorption shows 3 peaks, which have been traditionally labelled β1, β2, and β3 at 930, 1070, and 1375 K. Of these only β3 corresponds to a well defined state. Readsorption after heating to 950 or 1150 K results in a doubly peaked spectrum at 1070 and 1375 K. The β1 and β2 peaks obey complex desorption kinetics, probably corresponding to desorption and rearrangement. The coverage of β3 is 2.5 × 1014 molecules/cm2, suggesting that the c(2 × 2) LEED pattern corresponds to occupany of every other unit cell by a C or an O atom. For coverages ⩽ 1.5 × 1014 molecules/cm2 β3 desorption obeys second order kinetics with an activation energy of 83 ± 3 kcal/mole. For β3 the work function decreases from the clean W value by 0.1 eV, suggesting adsorption of C and O in the center of the W unit mesh, below the surface layer of W atoms. Readsorption on β and β precursor layers leads to formation of electropositive α-CO, with a multiply peaked thermal desorption spectrum, indicating the existence of different binding sites. Adsorption-heatingreadsorption, -heating-readsorption sequences indicate that additional changes in the α desorption spectrum occur, suggesting reconstruction in the β layer.
Artificial intersymbol interference (ISI) to exploit receiver imperfections for secrecy

Secure communication over a wireless channel in the presence of a passive eavesdropper is considered. We present a method to exploit the eavesdropper's inherent receiver vulnerabilities to obtain everlasting secrecy. An ephemeral cryptographic key is pre-shared between the transmitter and the legitimate receiver and is utilized to induce intentional intersymbol interference (ISI). The legitimate receiver uses the key to cancel the ISI while the eavesdropper, since it does not have the key, cannot do such. It is shown that although ISI reduces the capacity of the main channel, it can lead to a net gain in secrecy rate. The achievable secrecy rates for different ISI filter settings are evaluated and the proposed method is compared with other information-theoretic security schemes.
Concepts of nerve fiber development, 1839-1930.

It was thus the combination of observational and experimental approaches that ultimately led to confirmation of the outgrowth theory. The observational method was essential for defining various possible methods of nerve fiber development. The multicellular, protoplasmic bridge and outgrowth theories were each postulated to explain purely observational evidence. However, the lack of truly suitable equipment and techniques to study the developing nervous system made it impossible to agree on a single theory on this basis alone. The experimental method provided a means of choosing between these theories. Without the preceding observations that had led to the formulation of various hypotheses, however, the experimental approach might not have been so successful, for the power of this method is more of selection than of generation.
Correlation of β‐bend conformations of tetrapeptides with their activities in CD4‐receptor binding assays

Conformational analysis, based on ECEPP (Empirical Conformational Energy Program for Peptides) using the chain build-up procedure, was applied to determine the low-energy conformations for a series of tetrapeptides. The tetrapeptides are components of larger peptides which have been found to bind to the CD4 receptor of monocytes. Several previous studies have implicated the tetrapeptide units investigated here as being critical to the biological activities of the full peptides. Five such tetrapeptides were studied: Ser-Ser-Asn-Tyr (from ribonuclease A), Thr-Thr-Asn-Tyr (from peptide T, known to block human immunodeficiency virus from attaching to CD4+ T cells), Thr-Ile-Asn-Tyr (from polio virus coat protein, which is less active than the other peptides in binding to CD4 receptors), Ser-Ser-Ala-Tyr (from the gp 120 coat protein of human immunodeficiency virus, a variant of the peptide T sequence, active in blocking viral attachment to CD4+ cells), and the tetrapeptide from an active synthetic pentapeptide, Asn-Thr-Lys-Tyr (from Asn-Thr-Lys-Tyr-Thr). Using a 7 kcal/mol cutoff, the low-energy conformations for each peptide were computed. Approximately 20,000 conformations were computed for each tetrapeptide. Residue probability profiles were determined for each tetrapeptide. All tetrapeptides except for the polio sequence showed flexibility in the sense that many low-energy conformations were possible. In previous studies, it was postulated that the critical tetrapeptide units would adopt conformations similar to the one observed in a segment of ribonuclease A, residues 22-25, a beta-bend, which is part of an octapeptide segment (residues 19-26) that is homologous to the sequence of peptide T.(ABSTRACT TRUNCATED AT 250 WORDS)
Electron spin echo modulation and relaxation in polythiophene

Abstract Electron spin echo measurements on neutral poly (thiophene) show a clear modulation of the spin-echo decay. Analysis of the modulation and its Fourier transformed (ω) power spectrum indicates that the wave function of the spin defect is extended over ∼ 25 proton nuclei. The functional behavior of the longitudinal relaxation, T 1 , versus temperature is very similar to that observed previously for (CH) x , although T 1 values for poly (thiophene) are significantly longer.
Information transfer in city government

Abstract Innovative research addressing information use patterns is needed to test theory which can serve as a conceptual framework for planning and evaluating information delivery systems. The research project reported here uses structured observation to examine information transfer patterns in city government. Results and implications for public libraries are reported.
Efficient approximation algorithms for floorplan area minimization

Approximation has been shown to be an effective method for reducing the time and space costs of solving various floorplan area minimization problems. In this paper, we present several approximation techniques for solving floorplan area minimization problems. These new techniques enable us to reduce both the time and space complexities of the previously best known approximation algorithms by more than a factor of n and n/sup 2/ for rectangular and L-shaped sub-floorplans, respectively (where n is the number of given implementations). The efficiency in the time and space complexities is critical to the applicability of such approximation techniques in floorplan area minimization algorithms. We also give a technique for enhancing the quality of approximation results.
Programmed cell death in development and defense.

Around the time of this journal's first volume, the concept of PCD, i.e. the cell's active participation in its own demise, was introduced using the example of a plant cell infected by a fungus (1). This was 7 decades before the flurry of apoptosis research in animals. Death during an incompatible
Geographic Memory Bubbles: Recall of the Fifty United States

The participants (N = 180) in this study resided in two different states (i.e., North Dakota (ND) and Georgia (GA)). Each participant completed two tasks in a counterbalanced order: 1) free recall of the fifty United States and 2) recall of the fifty United States using a numbered map of the United States where they matched the state name to the actual state on the map. There were significant differences in recall by task. Also, there were significant chi-square values and a significant interaction for the states recalled by ND participants and GA participants. Participants demonstrated high recall (70 % or higher) for the 5–7 states surrounding their state of residence (e.g., primary geographic memory bubble). All participants had high recall for the states of WA, CA, NV, TX, FL, ME, AK and HI (e.g., secondary geographic memory bubble). The implications of these results relating to geographic illiteracy, instruction, and memory are discussed.
Analysis of systems with known transmission-frequency characteristics by Fourier integrals

LINEAR SYSTEMS in the general transient state may be analyzed effectively by means of the operational calculus, the Laplace transforms, or the Fourier transforms. Preceding articles in this series have introduced the operational calculus,1 the Laplace transforms,3 and certain essential mathematical ideas and processes pertaining to the manipulation of functions of a complex variable.2 The emphasis thus far has been on the analysis of systems involving known configurations of concentrated elements (resistance, inductance, and capacitance).
Functional impairment in Mexican Americans and non-hispanic whites with diabetes

Abstract There are virtually no data available describing the functional status of diabetic individuals. We therefore measured functional status using the Sickness Impact Profile (SIP) in 393 diabetic subjects and 486 nondiabetic control subjects identified from the San Antonio Heart Study, a population-based study of diabetes among Mexican Americans and non Hispanic whites. The SIP is a validated instrument that assesses the presence of health-related behavior changes and activity restrictions in 12 different categories. Functional impairment, defined as a SIP score of 2.0% or greater, was present among 36.6% of diabetic subjects. Following adjustments for age, Mexican Americans were 1.63 times more likely to experience functional impairment that non-Hispanic whites, although this difference was not statistically significant (95% confidence interval: 0.92–2.89). The categories in which subjects experienced impairment varied widely, but the category with the highest prevalence of impairment was “eating” (>40%). The prevalence of functional impairment was 45.9% among diabetic subjects with vascular complications, 31.8% among diabetic subjects without complications, and 16.7% among nondiabetic control subjects. Among all diabetic subjects impairment increased with age, duration of diabetes, fasting glucose, and BMI, and with insulin use and the presence of hypertension. In a multiple logistic regression model these factors (with the exception of insulin use) remained associated with the presence of functional impairment even after adjustment for the presence of vascular complications. If the factors responsible for this excess of functional impairment can be identified, an intervention might be designed which can lead to improvement in the quality of life for diabetic individuals.
Indentation modulus and yield point of Au(111), (001), and (110)

Nanoscale indentation experiments were performed on Au using the Interfacial Force Microscope (IFM) in an indentation mode. The indentation modulus and yield point were measured for three orientations of the Au surface: (111), (110), and (001). The indentation modulus for the (111) surface was found to be 36% greater than for the (001) surface and only 3% higher than the (110) surface. Additionally, the yield point was found to vary between orientations, but the shear stress resolved on {l_brace}111{r_brace} slip planes beneath the indenter on the axis of symmetry was found to be approximately 1.8 GPa for yield points of all three orientations.
Contribution of Women to U.S. Marketing Thought: The Consumers' Perspective, 1900-1940

This paper examines the early contributions of women to marketing thought with particular emphasis on marketing's evolving interest in the consumer. The emergence of marketing and home economics in the beginning of the present century provides a background for development of consumer theory and the relationships between these two disciplines. In addition, the contributions of women more closely aligned with mainstream marketing thought in the first half of the century are described and the significance of the “feminine perspective” and unique understanding of the consumer is demonstrated.
Modern perspectives on statistics for spatio-temporal data

Spatio-temporal statistical models are increasingly being used across a wide variety of scientific disciplines to describe and predict spatially explicit processes that evolve over time. Although descriptive models that approach this problem from the second-order covariance perspective are important, many real-world processes are dynamic, and it can be more efficient in such cases to characterize the associated spatio-temporal dependence by the use of dynamical models. The challenge with the specification of such dynamical models has been related to the curse of dimensionality and the specification of realistic dependence structures. Even in fairly simple linear/Gaussian settings, spatio-temporal statistical models are often over parameterized. This problem is compounded when the spatio-temporal dynamical processes are nonlinear or multivariate. Hierarchical models have proven invaluable in their ability to deal to some extent with this issue by allowing dependency among groups of parameters and science-based parameterizations. Such models are best considered from a Bayesian perspective, with associated computational challenges. Spatio-temporal statistics remains an active and vibrant area of research. WIREs Comput Stat 2015, 7:86-98. doi: 10.1002/wics.1341
The Role of Sexual Victimization in Women’s Perceptions of Others’ Sexual Interest

This study investigated the relationship between women’s sexual victimization experiences and their perceptions of sexual interest for an actor’s mundane, romantic, and sexual behaviors. Three hundred twenty-nine undergraduate women were divided into four mutually exclusive categories: women sexually victimized through verbal coercion, through intoxication, through force or threat of force, and women who reported only consensual sexual experiences. The women rated the sexual connotativeness of a list of dating behaviors, rating either a male or a female actor. Overall, women perceived more sexual interest in men’s behavior than in women’s comparable behavior. Moreover, women who had been victimized through force or threat of force perceived more sexual interest than nonvictimized women in a man’s target behaviors. There was no difference among women for a woman’s target behaviors. Women who have been sexually victimized may become more vigilant of men’s behaviors after experiencing sexual aggression.
Quaternary climate change as revealed by calcium carbonate fluctuations in western Equatorial Atlantic sediments

Abstract Fluctuations of total calcium carbonate content in eight western Equatorial Atlantic cores are used to evaluate Quaternary climate change. Both pelagic Mid-Atlantic Ridge and terrigenous-rich continental-rise cores that span the last 130,000 years show identical carbonate fluctuations which accurately reflect climatic oscillations during the Holocene, Wisconsin Glacial, and Last Interglacial. The carbonate fluctuations reveal a 20,000-year periodicity for warm-cold (interstadial-stadial) cycles with carbonate maxima reflecting interstadials and minima reflecting stadials. The carbonate fluctuations correlate in detail with other time scales for climatic oscillations deduced previously from radiometrically-dated sea-level maxima, solar insolation fluctuations, and North American ice-margin fluctuations. Pelagic cores spanning the last 500,000 years do not clearly reflect the 20,000-year cold-warm cycles but do show the 100,000-year glacial-interglacial cycles previously revealed by oxygen-isotope variations. The carbonate fluctuations in another core, which contains a continuous record of the last 1,800,000 years, indicates that 15 to 20 of these 100,000-year cycles have occurred during this period. The carbonate fluctuations of two cores suggest that the Atlantic circulated faster during glacials than during interglacials. A core from the Demerara Plateau (2000-m depth) has anomalous carbonate fluctuations plus expanded interglacial and shortened glacial sections that suggest faster circulation of surface water masses during glacials. The sediments of a pelagic core, which were deposited beneath the Antarctic Bottom Water, have undergone severe carbonate dissolution during glacials. These cycles apparently indicate an increase in production and faster circulation of the Antarctic Bottom Water during glacials.
Theory of geometric generating functionals

A geometrical and background field-dependent definition of the off-shelf effective action is considered, in the context of a theory of geometric generating functionals, which is based on a linear coupling with an external source J. The only requirements are geometry and a set of minimal properties related to the usefulness of the effective action. It is shown that the equivalence between the effective action and source formalisms in this geometrical framework is achieved by means of a multitensor coupling functional. Its form, as well as some identities for its expectation values, which arise as a consequence of this form, are explicitly displayed. It is finally argued that the one-particle irreducibility requirement for the effective action leads to its uniqueness.
Proteome profiling—pitfalls and progress

In this review we examine the current state of analytical methods in proteomics. The conventional methodology using two-dimensional electrophoresis gels and mass spectrometry is discussed, with particular reference to the advantages and shortcomings thereof. Two recently published methods which offer an alternative approach are presented and discussed, with emphasis on how they can provide information not available via two-dimensional gel electrophoresis. These two methods are the isotope-coded affinity tags approach of Gygi et al. and the two-dimensional liquid chromatography–tandem mass spectrometry approach as presented by Link et al. We conclude that both of these new techniques represent significant advances in analytical methodology for proteome analysis. Furthermore, we believe that in the future biological research will continue to be enhanced by the continuation of such developments in proteomic analytical technology.
Scribal Wisdom and a Biblical Proverb At Qumran

Many texts from Qumran are riddled with wisdom-not only the sapiential texts recently published, but also the foundational sectarian documents which have been known for decades.' Certain aspects of wisdom in the sectarian texts, however, merit further study, though features of this topic have been explored by scholars from Bardtke and Hengel to Tanzer, Newsom, and Lange.2 This paper examines an important feature of wisdom in key sectarian writings. This feature is its learned, literary character, in which a cluster of biblical texts are repeatedly employed, without citation
Polarity of isolated blastomeres from mouse morulae: detection of transcellular ion currents.

Eight- to sixteen-cell stage mouse morulae were dissociated with Ca2+-free medium into blastomeres that were labeled with fluoresceinated-succinylated Con A (FS-Con A) to mark their apical-basal axes. The vibrating probe was then used to map their extracellular current patterns. The average current density around normal blastomeres approached the resolution of the probe system (0.2 μA/cm2) and was undetectable in the majority of blastomeres. Since the current density at the measuring point outside the cell is known to increase with cell size in other systems, enlarged blastomeres were created by fusing together blastomeres of 4-cell stage embryos in 45% polyethylene glycol. Enlarged blastomeres were then aggregated with normal blastomeres using phytohemagglutinin and cultured to the 8- to 16-cell stage to allow them to become polarized. Such aggregates were then dissociated with Ca2+-free medium to recover polarized, enlarged blastomeres. The enlarged blastomeres were 30–65 μm in diameter and 70% of them generated a detectable current; currents were detected around 83% of those blastomeres larger than 40 μm in diameter. The current pattern in these most reliable cases was predominantly inward apical (1116 or 69%) and outward basal (1516 or 94%), with lateral currents about three-fold smaller in amplitude than these apical-basal currents. Lateral currents were undetectable in 53% of the cases. Preliminary data suggest that the inward current is carried in part by Na+ influx and is independent of the Na+,K+-ATPase over the short term. Transcellular ion currents were detectable as long as 4 hr after dissociation, and the apical-basal current pattern was usually stable during that time. In contrast, the fluorescent cap of FS-Con A faded within 7–30 min at 35°C but remained stable in 0.1% azide or 1.5 μg/ml cytochalasin D. The electrical polarity therefore persisted after the apical cap of Con A fluorescence was no longer visible. We propose that these transcellular ion currents may be involved in the establishment of blastomere polarity and describe a mechanism of action in an “ion current polarization” hypothesis.
The cytoplast: A unit structure in chromatophores

We followed the translocation of identifiable pigment granules in living erythrophores through normal aggregation and dispersion and observed that they always return in dispersion to the same location relative to the whole pigment complex. This is interpreted to mean that each granule occupies a fixed position within a unit structure, the cytoplast. This position is retained even though the cytoplast undergoes dramatic reversals in form from ellipsoid to spheroid and back again with each aggregation and dispersion. The major structural components of the cytoplast, besides pigment granules, are microtubules and microtrabeculae. The latter constitute an irregular lattice that is confluent with microtubules and contains the pigment granules. In aggregation, the microtrabeculae shorten and seemingly contribute to the contraction of the entire cytoplast plus pigment. In dispersion, the microtrabeculae elongate in an apparent restructuring of the ellipsoidal cytoplast. The microtubules, however, persist in the cell cortex and appear to give radial direction to the pigment motion.
The “Lessons” of Vietnam and Soviet Foreign Policy

This study systematically identifies the Soviet lessons of Vietnam as presented in eleven Soviet newspapers (specialized and regional as well as the central papers) and eight journals. Altogether, 1,585 citations were coded, representing more than 70 different lessons. A predominant finding is that the most common lessons the Soviet Union learned from Vietnam differed from their American counterparts: the Soviet lessons would not have warned the leadership about the dangers of military intervention in Afghanistan. A left/right scale was constructed, based on such issue clusters as why the communists won in Vietnam, the nature of imperialism, and the implications of Soviet policy in the Third World. Substantial variation was found among the media examined, many of which are linked to specific Soviet institutions. The implication is that Soviet foreign policy is contingent upon individual choices, institutional interplay, and changing contexts. This, in turn, suggests that Western policy makers should not lose sight of their capacity to influence the Soviet policy dialogue, and hence Soviet policy choices.
Plasmid DNA in colorless filamentous gliding bacteria.

Thirteen strains of colorless, filamentous, gliding bacteria, at least five of which are sulfide oxidizers, were screened for the presence of plasmid DNA. Agarose gel electrophoresis revealed that the sulfide oxidizing Beggiatoa alba strains B15LD (ATCC 33554), B18LD (ATCC 33555), and B25RD (ATCC 33556) each contained plasmids having molecular masses of ca. 12.8x106. Analysis of the EcoRI restriction endonuclease fragment patterns showed that the 12.8x106 plasmids in these three strains were similar. A single 8.1x106 plasmid was detected in cleared lysates of the mixotrophic sulfide oxidizer, Thiothrix nivea JP3. Two plasmid DNA bands were detected in cleared lysates of Beggiatoa spp. L-1401-2. Four plasmid DNA bands were detected in Vitreoscilla stercoraria strains ATCC 15218 and VT1. Plasmid DNA was not detected in the Beggiatoa strains ATCC 15551 and PD1, or in Vitreoscilla spp. 389 and V. beggiatoides B23SS. No apparent correlation was observed between the presence of certain plasmids and sulfide oxidation.
A unified approach to interpret unusual observations in heterogeneous ion exchange

Abstract Very high selectivity of uranium(VI) for anion-exchange resins at near neutral pH, gradual breakthrough of chromium(VI) in ion-exchange columns, increased mobility of heavy metals in soils, possible polymerization of molybdenum inside the ion exchanger, drastic reduction of heavy metal selectivity in the presence of ligands, etc., are examples of unusual observations in heterogeneous ion exchange and are apparently unrelated to each other. However, in all such diverse observations, the central atoms of interest have the ability to exist in different ionic forms, with different affinities toward the solid exchangers. As a result, the relative distributions of these ionic forms on the two sides of the solid—liquid interface are different and often associated with reactions including ionic dissociation, complexation, and polymerization, which cause such unusual behavior.
Results of Low Power Deicer tests on a swept inlet component in the NASA Lewis Icing Research Tunnel

Tests were conducted under a USAF/NASA Low Power Deicer program on two expulsive technologies to examine system performance on hardware representative of a modern aircraft part. The BF Goodrich Electro-Expulsive Deicing System and Pneumatic Impulse Ice Protection system were installed on a swept, compound curve, engine inlet component with varying leading edge radius, and tested through a range of icing and system operating conditions in the NASA Lewis Icing Research Tunnel. A description of the experimental procedure and results, including residual ice thickness, shed ice particle size, and changes in system energy/pressure characteristics are presented.
The frequency and fine specificity of B cells responsive to (4-hydroxy-3-nitrophenyl)acetyl in aged mice.

Abstract The B-cell response to NP-Hy of two murine strains has been analyzed in order to evaluate the affects of aging on B-cell repertoire expression. The results indicate that for both BALB/c mice (Igh a ) and B10.D2 mice (Igh b ) the frequency of (4-hydroxy-3-nitrophenyl)acetyl (NP)-responsive splenic B cells is approximately twofold lower, on a per B cell basis, in aged mice as compared to young adults. However, as with previous assessments of the response to DNP-Hy in aged mice, the frequency of newly generated surface immunoglobulin negative bone marrow precursor cells specific for NP in aged BALB/c mice is the same as in young mice. The decrease in frequency of responsive splenic B cells is not accompanied by a measurable decrease in repertoire diversity or changes in clonotype distribution as assessed by (a) representation of κ vs λ light chain-bearing antibodies, (b) binding of monoclonal antibodies to a panel of analogues of NP, and (c) the proportionate representation of B10.D2 monoclonal antibodies that bear NP d idiotypic determinants. By these criteria it appears that down-regulation of B cells as they mature and emerge from the bone marrow of aged mice is pan-specific and does not disproportionately affect B cells of a predominant clonotype family. Consistent with other investigations which have demonstrated differences in secreted antibodies of immunized aged vs young mice, we have observed that 4 weeks after immunization of B10.D2 mice with NP-BSA, the frequency of newly generated secondary B cells is lower in aged than in young mice and the generation of λ-bearing secondary precursor cells is particularly low. Thus, clonotype-specific down-regulation may play a role in shaping the B-cell repertoire subsequent to immunization of aged mice.
Correlation of ectodesmata number with nonspecific resistance to initial virus infection.

Abstract The resistance of T.I. 245 tobacco to initial infection by necrotic strains of cucumber mosaic or tobacco mosaic viruses was markedly decreased by darkening plants before inoculation, by immersing leaves in water at 45° for 2 minutes, or by keeping plants at 16° for 3 days before inoculation. There was more chlorogenic acid oxidase and peroxidase in the resistant T.I. 245 tobacco than in the susceptible T.I. 787 tobacco. Treatments decreasing resistance, however, did not significantly alter the content of these two enzymes. In each variety virus became resistant at about the same rate, after inoculation, to external application of infection-inhibiting Phytolacca extract. Bentonite stimulated infectivity of TMV-RNA to about the same extent on each variety, indicating that resistance was not due to destruction of virus by leaf ribonuclease. Varietal differences in susceptibility and alterations in susceptibility due to age were correlated with numbers of ectodesmata demonstrable in the outer walls of epidermal cells. Similarly, darkening and temperature treatments that increased susceptibility of T.I. 245 tobacco also increased numbers of ectodesmata. These treatments had little effect on ectodesmata numbers or susceptibility of T.I. 787 tobacco. It was concluded that ectodesmata function as infection sites, and their number or condition determine relative susceptibility.
Fertility therapy and the risk of very low birth weight.

Objective To test the hypothesis of an association between maternal infertility therapy and the risk of very low birth weight (VLBW), defined as birth weight less than 1500 g, independent of the risk of multiple births, and to estimate the contribution of infertility therapy to the national incidence of VLBW. Methods The National Maternal and Infant Health Survey conducted in 1988 was used to develop statistics describing outcomes among this birth cohort and to construct logistic regression models evaluating fertility therapy as an independent risk factor for VLBW. Results An estimated 10.1% of live births and 18.2% of VLBW births nationally were associated with either maternal subfertility or infertility therapy (6.8% and 11.4%, respectively) The risk of VLBW among women concerned with subfertility (ie, receiving diagnostic testing or advice on timing intercourse) was 1.4 (95% confidence interval [CI] 1.1, 1.9), whereas that for women undergoing therapeutic interventions (ie, ovarian stimulation, surgery, in vitro fertilization or artificial insemination) was 2.6 (95% CI 2.1, 3.2). Accounting for effects of multiple gestation, maternal age, and a history of miscarriage, the odds ratios for the concerned and therapy groups were 1.5 (95% CI 1.1,1.9) and 2.0 (95% CI 1.5, 2.5), respectively. Black women were less likely to use fertility therapy but more likely to experience a therapy-related VLBW. Conclusion Fertility therapy is associated with an important portion of all VLBW and with an elevated risk of VLBW, related only in part to an increased risk of multiple gestations. Women expressing concern about subfertility but not receiving therapy are also at increased risk of VLBW, suggesting that a history of infertility may mediate part of the risk associated with fertility therapy.
Resituating the Community College in a Global Context.

From locally focused institutions intent on access and affordability to higher education, workforce preparation, and community engagement, the contemporary community college is poised as a global partner for the democratization and development of a global workforce.
Who Is Lost to Followup?: A Study of Patients with Distal Radius Fractures

Distal radius fractures are the most common upper extremity fracture, representing one-sixth of all fractures treated in emergency departments nationwide. Beyond the initial reduction and immobilization of these fractures, providing proper followup to ensure maintenance of the reduction and identify complications is necessary for optimal recovery of forearm and wrist functions. We sought to identify the clinical and demographic factors that characterize patients with distal radius fractures who do not return for followup and to assess the underlying causes for their poor followup rates. Compared with patients who were compliant with followup, those lost to followup had lower Physical and Mental Health scores on the SF-36 forms, more often were treated nonoperatively, and more likely had not surpassed secondary education. However, we found no difference between these two groups based on age, gender, mechanism of injury, marital status, or hand dominance. Early identification of patients who potentially are noncompliant can result in additional measures being taken to ensure the patient’s return to the treating hospital and physicians. This in turn will prevent complications attributable to lack of followup and allow more accurate assessment of results, thereby improving patient outcomes.
Parallel algorithms for solving systems of nonlinear equations

Abstract In this paper, parallel algorithms are proposed for solving both systems of nonlinear algebraic equations and unconstrained optimization problems. Theoretical results for their convergence and orders of convergence are also presented. The proposed algorithms are analytically compared in terms of their time efficiencies and speed-up ratios.
The eponymous, anonymous Joseph Stefan

Abstract A brief biography of the Austrian/Slovenian physicist Joseph Stefan is given, along with an outline of some of the most notable work he did at the University of Vienna including radiation heat transfer and solid–liquid phase change.
Modeling the solid-like behavior of entangled polymer nanocomposites at low frequency regimes

Abstract A theory for the linear viscoelastic behavior of entangled polymeric liquids reinforced with non-aggregated colloidal nanoparticles is presented. Composites with low filler concentration and strong polymer–particle interaction are considered. A fraction of entangled chains is assumed to be reversibly adsorbed on the surface of fillers, due to the affinity between the polymer molecules in the matrix and dispersed filler particles. The relaxation of the system is analyzed by the combination of stress relaxation functions for free and adsorbed polymer chains. It is demonstrated that the emergence of solid-like behavior at low frequency regimes, is due to the significant slow down in relaxation of adsorbed chains. Fitting the model predictions with relevant experimental data indicates that while the effect of constraint release should be considered to obtain a reasonable estimation of neat polymer behavior, the linear combination of stress relaxation functions of free and adsorbed chains (i.e., no thermal constraint release) leads to a better agreement with experimental data of filled systems.
Transmission of STIs/HIV at the partnership level: Beyond individual-level analyses

Mathematical modeling of transmission dynamics of sexually transmitted infections (STIs) and HIV has considerably advanced HIV research by highlighting the importance of certain types of partnerships in epidemic spread. Notably, concurrent partnerships, defined as a sexual partnership in which one or more of the partnership members have other sexual partners while continuing sexual activity with the original partner, have been shown to play a fundamental role in potentiating the spread of STIs and HIV. Risk behaviors such as concurrency and sex without condoms as well as STI/HIV prevalence vary with physical, social, and emotional factors within partnerships. The efficiency of STI/HIV transmission appears to vary across types of concurrent partnerships according to the differing dynamics within them. Previous research on partnership dynamics has improved our understanding of the multidimensional aspects of sexual partnering, but little is understood of how these aspects of sexual partnering interact and increase risks for HIV, nor how types of partnerships, partnership dynamics, and concurrency work together to affect both the behavior of condom use and the biological transmission of disease. In this article, we discuss the need to extend our understanding of concurrency to include partnerships among men who have sex with men (MSM) and to differentiate between types of partnerships and to develop interventions to modify risk within partnerships. We also introduce a conceptual framework that reflects how individual and partner characteristics influence partnership dynamics that in turn influence risk behaviors, such as concurrency and not using condoms, and associated risks for STIs and HIV.
Seasonal change in neuron size and spacing but not neuronal recruitment in a basal ganglia nucleus in the avian song control system

Neural plasticity in the song control system of seasonally breeding songbirds accompanies seasonal changes in singing behavior. The volume of Area X, a song control nucleus that forms a portion of the avian basal ganglia, is 75% larger in the spring than it is in the fall. The neuronal basis of the seasonal plasticity in Area X is largely unknown, however. We examined neuronal attributes of Area X in wild adult male song sparrows (Melospiza melodia) captured during the spring and the fall after being implanted for 30 days with osmotic pumps containing [3H]thymidine. We measured the volume of Area X from thionin-stained sections, and neuronal density and number, and average area of the soma from sections labeled with an antibody against Hu, a neuron-specific protein. We sampled two neuron classes: “small” neurons that were most likely striatal-like spiny neurons and “large” neurons, which most likely included pallidal-like projection neurons. We also analyzed seasonal patterns of neuronal recruitment to Area X. The average area of the soma and neuronal spacing for both neuronal classes were greater in breeding birds. There was no difference in total neuron number for both neuronal classes between seasons. The average area of the soma and density and number of newly recruited neurons did not vary across seasons. These results demonstrate that seasonal plasticity in Area X includes changes in neuron size and neuronal density, but not changes in the rate at which new neurons are recruited. J. Comp. Neurol. 481:276–283, 2005. © 2004 Wiley-Liss, Inc.
Nontypeable Haemophilus influenzae: understanding virulence and commensal behavior

Haemophilus influenzae is genetically diverse and exists as a near-ubiquitous human commensal or as a pathogen. Invasive type b disease has been almost eliminated in developed countries; however, unencapsulated strains – nontypeable H. influenzae (NTHi) – remain important as causes of respiratory infections. Respiratory tract disease occurs when NTHi adhere to or invade respiratory epithelial cells, initiating one or more of several proinflammatory pathways. Biofilm formation explains many of the observations seen in chronic otitis media and chronic bronchitis. However, NTHi biofilms seem to lack a biofilm-specific polysaccharide in the extracellular matrix, a source of controversy regarding their relevance. Successful commensalism requires dampening of the inflammatory response and evasion of host defenses, accomplished in part through phase variation.
What defines a view

Abstract At a given instant we see only visible surfaces, not an object's complete 3D appearance. Thus, objects may be represented as discrete ‘views’ showing only those features visible from a limited range of viewpoints. We address how to define a view using Koenderink's (Koenderink & Van Doorn, Biol. Cybernet. 32 (1979) 211.) geometric method for enumerating complete sets of stable views as aspect graphs. Using objects with known aspect graphs, five experiments examined whether the perception of orientation is sensitive to the qualitative features that define aspect graphs. Highest sensitivity to viewpoint changes was observed at locations where the theory predicts qualitative transitions, although some transitions did not affect performance. Hypotheses about why humans ignore some transitions offer insights into mechanisms for object representation.
Task scheduling in heterogeneous distributed systems with security and QoS requirements

Heterogeneous distributed systems are continuously being deployed, e.g., P2P and military command, control, communications, computers, and intelligence (C4I). Many of these applications trade-off quality of service (QoS) and security. In this paper, we study the problem of allocating and scheduling a set of dependent tasks with security and QoS requirements on a set of heterogeneous sites. This problem is at least as hard as the basic NP-hard problem of scheduling a directed acyclic graph (DAG) on multiple processors. In particular, we make the following contributions: 1) we formulate the problem as an optimisation problem; 2) we use a branch and bound (BB 3) we propose a heuristic algorithm to provide a near optimal solution for the scheduling of the assigned tasks on a site to maximise the QoS provided by this site in a polynomial time; 4) we evaluate the heuristic algorithm and compare it with some baseline algorithms using variations of synthetic workloads.
Structural instability of the theory of simple competition

“It is well known that two microbial populations competing for a single nutrient in a homogeneous environment with time-invariant inputs cannot coexist in a steady-state” ( Baltzis & Fredrickson, 1983 ). It is perhaps less well known that an arbitrarily small deviation from the single nutrient dependence, homogeneity or time-invariance renders this statement invalid. This paper establishes that the theory of simple competition of two species for a single growth-limiting substrate is structurally unstable. Conclusions based on such a theory therefore cannot be expected, a priori , to apply to systems for which there exist even small deviations from simple competition. It then becomes necessary to establish how the conclusions are modified under the introduction of such perturbations. The presence of an additional substrate, for which both species exhibit a weak affinity of O ( ɛ ), gives rise to new phenomena, but only within an interval of dilution rates whose extent decreases with ɛ . However, within this interval either stable coexistence or conditional exclusion occurs, depending on the relative affinities for the additional substrate. Such states persist for arbitrarily small ɛ , though their observability and significance decreases with ɛ . These conclusions are independent of the particular functional forms used to model the substrate dependence, and characterize an entire class of competitive systems in which specific models based on Michaelis-Menten, Monod, Holling or sigmoidal type kinetics arise as particular instances. Despite the impossibility of ever establishing with limitless accuracy whether an observed system is purely one of simple competition for a single growth-limiting substrate, conclusions based on the theory of simple competition, such as the principle of competitive exclusion, have been universally applied to understand species diversity and community structure. This paper formulates those predictions of the theory of simple competition which survive small perturbations in the structure of the system, enabling conclusions such as the principle of competitive exclusion to be applied in a consistent manner.
Reproductive consequences of exposure to waterborne phytoestrogens in male fighting fish Betta splendens.

Phytoestrogens are plant compounds that can act as endocrine disruptors in vertebrates. Biologically active levels of phytoestrogens have been found in aquatic habitats near wood pulp and paper mills, biofuel manufacturing plants, sewage-treatment plants, and agricultural fields. Phytoestrogens are known to cause hormonal and gonadal changes in male fish, but few studies have connected these effects to outcomes relevant to reproductive success. In one experiment, we exposed sexually mature male fighting fish Betta splendens to environmentally relevant (1 μg L−1) and pharmacological concentrations (1000 μg L−1) of the phytoestrogen genistein as well as to a positive control of waterborne 17β-estradiol (E2; 1 μg L−1), and a negative control of untreated water. In a second experiment, we exposed male B. splendens to environmentally relevant concentrations (1 μg L−1) of genistein and β-sitosterol singly and in combination as well as to the positive and negative controls. All exposures were 21 days in duration. We measured sex-steroid hormone levels, gonadosomatic index (GSI), sperm concentration and motility, and fertilization success in these fish. We found that exposure to genistein did not affect circulating levels of the androgen 11-ketotestosterone or the estrogen E2 relative to negative-control fish. We also found that neither of the compounds nor their mixture affected GSI, sperm concentration or motility, or fertilization success in exposed fish relative to negative-control fish. However, fish exposed to phytoestrogens showed some evidence of fewer but more motile sperm than fish exposed to the positive control E2. We conclude that sexually mature male B. splendens are relatively immune to reproductive impairments from short-term exposure to waterborne phytoestrogens.
Social anxiety symptoms uniquely predict fear responding to 35% CO2 challenge

Abstract The vast majority of biological challenge studies have focused on panic disorder though there is a small literature suggesting that patients with social anxiety disorder (SAD) show comparable responding. The SAD literature is potentially confounded, however, by the fact that many patients with SAD experience panic attacks. These patients also show elevated negative affect and anxiety sensitivity, factors that are also associated with increased fear responding to challenge. By controlling for these factors, the present report was able to evaluate whether social anxiety symptoms were uniquely associated with fearful responding to a 35% CO 2 challenge. A large nonclinical sample of young adults ( N = 120) screened for a history of panic attacks completed a 35% CO 2 challenge. Those high (versus low) in social anxiety showed approximately 2.5 times greater risk for experiencing substantial increases in anxiety in response to the challenge. This significant association was maintained after controlling for anxiety sensitivity and general negative affect. These data provide novel evidence suggesting that social anxiety symptoms are uniquely associated with anxious responding to 35% CO 2 challenge and this sensitivity appears to precede the development of panic attacks.