cssi/SciSciGPT-SciSciNet huggingface dataset:
A Phylogenetic Rate Parameter Indicates Different Sequence Divergence Patterns in Orthologs and Paralogs

Heterotachy-the change in sequence evolutionary rate over time-is a common feature of protein molecular evolution. Decades of studies have shed light on the conditions under which heterotachy occurs, and there is evidence that site-specific evolutionary rate shifts are correlated with changes in protein function. Here, we present a large-scale, computational analysis using thousands of protein sequence alignments from animal and plant proteomes, representing genes related either by orthology (speciation events) or paralogy (gene duplication), to compare sequence divergence patterns in orthologous vs. paralogous sequence alignments. We use sequence-based phylogenetic analyses to infer overall sequence divergence (tree length/number of sequences) and to fit site-specific rates to a discrete gamma distribution with a shape parameter α. This inference method is applied to real protein sequence alignments, as well as alignments simulated under various models of protein sequence evolution. Our simulations indicate that sequence divergence and the α parameter are positively correlated when sequences evolve with heterotachy, meaning that inferred site rate distributions appear more uniform as sequences diverge. Divergence and α are also positively correlated in both orthologous and paralogous genes, but the average increase in α (as a function of divergence) is significantly higher in paralogous protein alignments than in orthologous alignments. This result is consistent with the widely held view that recently duplicated proteins initially evolve under relaxed selective pressure, promoting functional divergence by accumulation of amino acid replacements, and hence experience more evolutionary rate fluctuations than orthologous proteins. We discuss these findings in the context of the ortholog conjecture, a long-standing assumption in molecular evolution, which posits that protein sequences related by orthology tend to be more functionally conserved than paralogous proteins.
THE ROLE OF THE INTERNET IN CHANGING KNOWLEDGE ECOLOGIES

To a greater extent than is often acknowledged, the modern scientific and university-based knowledge system is a creature of the society of the printing press. Until the turn of the twentyfirst century, print was the medium of scholarly communication. Then, quite suddenly at the turn of the twenty-first century, digital text begins to displace print as the primary means of access to the knowledge of academicians. This article explores some of the consequences of this change. To what extent do digital technologies of representation and communication reproduce the knowledge systems of the half-millennium long history of the modern university or do they disrupt and transform them? To answer this question, this article will explore key aspects of contemporary transformations, not just in the textual forms of digital representation, but the emerging social forms that digitisation reflects, affords and supports. This we call the “social web”, a term we use to describe the kinds of relationships to knowledge and culture that are emerging in the era of pervasively interconnected computing. What, then, are the impacts and potentials of these changes on the processes of formation of new knowledge?
Introduction to the MTO Nancarrow Symposium

[1] This MTO Symposium on the Music of Conlon Nancarrow grew out of an online symposium held September 27-October 27, 2012 in honor of Nancarrow's centennial. From the start of the planning for the event, Daphne Leong (Program Committee Chair) and I hoped MTO would be a partner. We are very pleased now to present this collection of articles to the readers of MTO.(1) They represent the four main branches of current work on Nancarrow: arranging his music for performers, adapting it to contemporary technology, analyzing the scores, and researching his life history.[2] Half of the presenters in the symposium participated in two major international events honoring Nancarrow in 2012, first at the The Music of Conlon Nancarrow: Impossible Brilliance conference held in April at London's Southbank Centre. Dominic Murcott brought together an international group of Nancarrow experts including Charles Amirkhanian, Felix Meyer, Kyle Gann, Trimpin, Rex Lawson, Wolgang Heisig, and Yoko Sugiura-Nancarrow to discuss and perform Nancarrow's music. The complete Studies for player piano were played on an authentic instrument along with performances by the London Sinfonieta. In November most of the same group gathered for the Nancarrow at 100: A Centennial Celebration organized by Charles Amirkhanian in Berkeley, California along with Peter Garland, David "Mako" Nancarrow (son), and the Bugallo-Williams piano duo. This event will likely go down in history as the greatest gathering of Nancarrow cognoscenti. Audience members included Bob Shumaker (the engineer for Nancarrow's recordings), Mary Oppen (a longtime friend), Eva Soltes (Nancarrow's manager), and Luis Stephens (Nancarrow's stepson). Recordings of most of the events are available online due to the generosity of radiom.org.[3] Helena Bugallo and Amy Williams have achieved acclaim for their performances and two CDs of arrangements of works by Nancarrow. Bugallo's contributions as a Nancarrow scholar are represented in this issue in "Harmonic and Non-Harmonic Temporal Structures in Nancarrow's Study No. 47 for Player Piano," which includes a critical score and rhythmic analysis for a piece that has only previously been available on recordings.[4] Clifton Callender's "Performing the Irrational: Paul Usher's Arrangement of Nancarrow's Study No. 33" explores compositional, mathematical, and performance issues involved in the approximation of irrational rhythms. Callender concludes with a close study of the Arditti Quartet's remarkable performance of Study No. 33, in Usher's arrangement.[5] Dominic Murcott's "Tomorrow's Music on Yesterday's Machines" surveys the many ways the Studies have been presented in recordings, and explores the artistic and practical questions that arose while preparing the comprehensive series of concerts for the "Impossible Brilliance" festival. …
Distinguishing features of natural and forced oscillations

Synchronous power systems often experience two types of oscillatory responses: natural and forced. Natural oscillations are a transient response characterized by the electromechanical oscillation modes. If one or more of these modes are undamped, a sustained oscillation occurs with the system in a near unstable condition. Alternatively, forced oscillations are typically caused by some rouge input driving the system into a sustained oscillation. An example is an ill-operating power-plant steam valve oscillating in a limit-cycle. This paper examines the unique features that may allow one to distinguish between a very lightly-damped (or undamped) natural oscillation and a forced oscillation. We first provide a unique mathematical representation for forced versus natural oscillations. The model is then used to show that the noise response of the system under the undamped natural case is considerably different than under the forced case. We show a spectral approach for using this difference to distinguish between the oscillation types.
Sonographic detection and fine-needle aspiration biopsy of nonpalpable recurrent or metastatic melanoma in subcutaneous tissues

Subcutaneous or lymph node metastases from melanoma may not be palpable because of their small size, their distance from the skin surface, or their location in an area of fibrosis due to previous surgery or irradiation. High-resolution sonography has been used to detect clinically occult foci of recurrent or metastatic melanoma, whereas real-time, ultrasound-guided, fine-needle aspiration biopsy provided cytologic confirmation. Following excision of cutaneous melanoma, sonographic follow-up of the areas of the surgical scar and lymphatic drainage is recommended whenever residual disease is suspected or when clinical evaluation is limited by postoperative or postradiation changes. Any nonpalpable hypoechoic mass detected in those areas should have a biopsy under real-time sonographic guidance.
Rv2131c from Mycobacterium tuberculosis is a CysQ 3'-phosphoadenosine-5'-phosphatase.

Mycobacterium tuberculosis (Mtb) produces a number of sulfur-containing metabolites that contribute to its pathogenesis and ability to survive in the host. These metabolites are products of the sulfate assimilation pathway. CysQ, a 3′-phosphoadenosine-5′-phosphatase, is considered an important regulator of this pathway in plants, yeast, and other bacteria. By controlling the pools of 3′-phosphoadenosine 5′-phosphate (PAP) and 3′-phosphoadenosine 5′-phosphosulfate (PAPS), CysQ has the potential to modulate flux in the biosynthesis of essential sulfur-containing metabolites. Bioinformatic analysis of the Mtb genome suggests the presence of a CysQ homologue encoded by the gene Rv2131c. However, a recent biochemical study assigned the protein’s function as a class IV fructose-1,6-bisphosphatase. In the present study, we expressed Rv2131c heterologously and found that the protein dephosphorylates PAP in a magnesium-dependent manner, with optimal activity observed between pH 8.5 and pH 9.5 using 0.5 mM MgCl2. A...
Composites with Inclusions of Negative Bulk Modulus: Extreme Damping and Negative Poisson’s Ratio

The effect of a negative bulk modulus phase in elastic composites is studied. Negative bulk modulus K<0 is shown to be possible in selected unit cells. In isotropic solids, K<0 can be attained when negative Poisson’s ratio is sufficiently small, below the stability limit (for stress control) 1/4 1. Such materials, if used as inclusions, are predicted to be stable with respect to the band formation, even if they are large. Composites with spherical inclusions of negative bulk moduli are shown to exhibit negative Poisson’s ratio and anomalies in composite bulk modulus and Young’s modulus (and in the corresponding mechanical damping) but not in the shear modulus.
In Depth Analysis of AVCOAT TPS Response to a Reentry Flow

Modeling of the high altitude portion of reentry vehicle trajectories with DSMC or statistical BGK solvers requires accurate evaluation of the boundary conditions at the ablating TPS surface. Presented in this article is a model which takes into account the complex ablation physics including the production of pyrolysis gases, and chemistry at the TPS surface. Since the ablation process is time dependent the modeling of the material response to the high energy reentry flow starts with the solution of the rarefied flow over the vehicle and then loosely couples with the material response. The objective of the present work is to carry out conjugate thermal analysis by weakly coupling a flow solver to a material thermal response model. The latter model solves the one dimensional heat conduction equation accounting for the pyrolysis process that takes place in the reaction zone of an ablative thermal protection system (TPS) material. An estimate of the temperature range within which the pyrolysis reaction (decomposition and volatilization) takes place is obtained from Ref. [1]. The pyrolysis reaction results in the formation of char and the release of gases through the porous charred material. These gases remove additional amount of heat as they pass through the material, thus cooling the material (the process known as transpiration cooling). In the present work, we incorporate the transpiration cooling model in the material thermal response code in addition to the pyrolysis model. The flow in the boundary layer and in the vicinity of the TPS material is in the transitional flow regime. Therefore, we use a previously validated statistical BGK method [2] to model the flow physics in the vicinity of the micro‐cracks, since the BGK method allows simulations of flow at pressures higher than can be computed using DSMC.
The TWEAK–Fn14 dyad is involved in age-associated pathological changes in skeletal muscle

Progressive loss of skeletal muscle mass and strength (sarcopenia) is a major clinical problem in the elderly. Recently, proinflammatory cytokine TWEAK and its receptor Fn14 were identified as key mediators of muscle wasting in various catabolic states. However, the role of the TWEAK-Fn14 pathway in pathological changes in skeletal muscle during aging remains unknown. In this study, we demonstrate that the levels of Fn14 are increased in skeletal muscle of 18-month old (aged) mice compared with adult mice. Genetic ablation of Fn14 significantly increased the levels of specific muscle proteins and blunted the age-associated fiber atrophy in mice. While gene expression of two prominent muscle-specific E3 ubiquitin ligases MAFBx and MuRF1 remained comparable, levels of ubiquitinated proteins and the expression of autophagy-related molecule Atg12 were significantly reduced in Fn14-knockout (KO) mice compared with wild-type mice during aging. Ablation of Fn14 significantly diminished the DNA-binding activity of transcription factor nuclear factor-kappa B (NF-κB), gene expression of various inflammatory molecules, and interstitial fibrosis in skeletal muscle of aged mice. Collectively, our study suggests that the TWEAK-Fn14 signaling axis contributes to age-associated muscle atrophy and fibrosis potentially through its local activation of proteolytic systems and inflammatory pathways.
Surviving an Identity Crisis: A Revised View of Chromatin Insulators in the Genomics Era

The control of complex, developmentally regulated loci and partitioning of the genome into active and silent domains is in part accomplished through the activity of DNA-protein complexes termed chromatin insulators. Together, the multiple, well-studied classes of insulators in Drosophila melanogaster appear to be generally functionally conserved. In this review, we discuss recent genomic-scale experiments and attempt to reconcile these newer findings in the context of previously defined insulator characteristics based on classical genetic analyses and transgenic approaches. Finally, we discuss the emerging understanding of mechanisms of chromatin insulator regulation. This article is part of a Special Issue entitled: Chromatin and epigenetic regulation of animal development.
Physician Preference is a Major Factor in Management of Vesicoureteral Reflux

Background Known factors affecting the management of vesicoureteral reflux (VUR) include reflux grade, infection frequency, age and gender. We hypothesized that provider preference is highly associated with management.
Effect of viscosity ratio on structure evolution in miscible polymer blends

Structure development through the softening/melting compounding regime is investigated for very-low-viscosity-ratio model miscible blends consisting of poly(styrene-co-acrylonitrile) (SAN)/poly(methyl methacrylate) (PMMA) and polyethylene (PE)/polyethylene. Blends with viscosity ratios of 1.12, 0.11, 0.03, 0.003, and 0.00015 are pigmented, compounded, and visually interrogated. These experiments reemphasize both the importance of the softening/melting regime to the development of morphology in low-viscosity-ratio, miscible blends, and the dynamic similarity between the behavior of these miscible blends and their immiscible counterparts at short mixing times. Additionally, these experiments reveal the presence of a phase-inversion-like process in the lowest viscosity-ratio blends, as evidenced by both local and global maxima in the mixer torque traces. This is the first such observation in a miscible polymer blend. We postulate a mechanism of morphology development that incorporates the Scott/Macosko lacing/sheeting mechanism, as well as the observed phase-inversion-like process. Finally, we confirm that the presence of a low-viscosity additive significantly delays the onset of mixing, even when thermodynamically miscible with the major component.
Nd and Sr isotopic study of a mafic layer from Ronda ultramafic complex

Detailed isotopic and trace element analyses of a garnet clinopyroxenite layer from the Ronda ultramafic complex demonstrate the difficulty in obtaining primary mantle information from orogenic lherzolites. However, isotope systematics suggest that mafic layers at Ronda were formed 22±2 Myr ago from a reservoir with initial Nd and Sr isotope ratios of 0.51317 and 0.7025, respectively, and represent the products of interaction between normal mid-oceanic ridge tholeiite and depleted mantle peridotite.
A Simple Model for Inelastic Scattering.

A simple model for inelastic scattering may be obtained by suitably generalizing scattering from a square well. The generalization introduces matrices into the quantum‐mechanical scattering equations. These equations may be solved exactly to give an explicit expression for the scattering matrix. In this paper we first describe and solve the model, and then discuss the results it predicts for a simple example. We will see that even a simple inelastic system can exhibit rich scattering behavior.
Alternative Technology for Double Patterning Process Simplification

In this paper, we will present experimental results on sub-40nm node patterning of DRAM and some technical issues for capping freezing in simplified double patterning lithography. Lithography resolution limit of single pattern is 40nm in ArF immersion process. For sub-40nm patterning, we have to use double patterning lithography or EUV process. But, double patterning lithography process is very complicated and expensive solution. And EUV volume production technology will be not ready until 2012. Therefore, we have tried a simplified double patterning lithography.
New allyl selenide and trialkylphosphine selenide precursors for metalorganic vapor phase epitaxy of ZnSe

Abstract New allyl selenide and trialkylphosphine selenide reagents; specifically, t-butylallyl selenide (tBASe) and tripropylphosphine selenide, are described for the metalorganic vapor phase epitaxy (MOVPE) of ZnSe. The gas-phase chemistry of allyl selenide precursors is discussed, with emphasis on reactions leading to carbon incorporation. Secondary ion mass spectrometry shows a negligible carbon incorporation in ZnSe films grown from tBASe even at high [VI]/[II] ratios, in contrast to a carbon concentration of 10 21 cm −3 in ZnSe films grown from diallyl selenide and methyl allyl selenide. The low carbon concentration is attributed to the t-butyl group precluding internal rearrangement reactions responsible for carbon incorporation. Low temperature growth and short residence times are critical to minimizing alkyl group redistribution reactions that lead to formation of potential carbon precursors; specifically, diallyl selenide. Good surface morphology on (001) GaAs and photoluminescence spectra with sharp near-band-edge excitonic emission is reported. The need to reduce hydrogen incorporation to improve nitrogen doping characteristics motivates the development of alternative Se precursors circumventing formation of Se-H moieties. Phosphine selenides are proposed as a promising family of reagents and results are presented for growth of ZnSe with tripropylphosphine selenide and dimethylzinc.
Soil nitrogen and carbon dynamics in a fragmented landscape experiencing forest succession

Forest fragmentation is an increasingly common feature across the globe, but few studies examine its influence on biogeochemical fluxes. We assessed the influence of differences in successional trajectory and stem density with forest patch size on biomass quantity and quality and N transformations in the soil at an experimentally fragmented landscape in Kansas, USA. We measured N-related fluxes in the laboratory, not the field, to separate effects of microclimate and fragment edges from the effects of inherent biomass differences with patch size. We measured net N mineralization and N2O fluxes in soil incubations, gross rates of ammonification and nitrification, and microbial biomass in soils. We also measured root and litterfall biomass, C:N ratios, and δ13C and δ15N signatures; litterfall [cellulose] and [lignin]; and [C], [N], and δ13C and δ15N of soil organic matter. Rates of net N mineralization and N2O fluxes were greater (by 113% and 156%, respectively) in small patches than in large, as were gross rates of nitrification. These differences were associated with greater quantities of root biomass in small patch soil profiles (664.2 ± 233.3 vs 192.4 ± 66.2 g m−2 for the top 15 cm). These roots had greater N concentration than in large patches, likely generating greater root derived organic N pools in small patches. These data suggest greater rates of N cycling in small forested patches compared to large patches, and that gaseous N loss from the ecosystem may be related to forest patch size. The study indicates that the differences in successional trajectory with forest patch size can impart significant influence on soil N transformations in fragmented, aggrading woodlands.
Effects of transforming growth factor-β and platelet-derived growth factor on oligodendrocyte precursors: Insights gained from a neuronal cell line

Conditioned medium derived from a rat central nervous system neuronal cell line B104 (B104 CM) was shown previously to contain uncharacterized potent mitogen(s) for oligodendrocyte/type-2 astrocyte (O-2A) progenitor cells. In this study, we demonstrated that B104 cells produce and secrete platelet-derived growth factor (PDGF)-AA homodimer, but not PDGF-B chain. B104 cells did not express other known potent mitogens for O-2A progenitor cells, including fibroblast growth factor-2 and neurotrophin-3. Unexpectedly, B104 cells also expressed transcripts of transforming growth factor-beta1 (TGF-beta1) and -beta2 (TGF-beta2), which are known to regulate O-2A progenitor cell differentiation and proliferation, and secreted exclusively the 25-kDa active forms of TGF-beta1 and TGF-beta2. Neutralization of B104 CM with anti-PDGF-AA antibody decreased proliferation of O-2A progenitor cells, whereas neutralization with anti-TGF-beta antibodies had no effect. The combination of PDGF and TGF-beta on proliferation was not equivalent to the effect of B104 CM, indicating the possibility of an unidentified growth factor. B104 CM maintained a high expression of PDGF-alpha receptor in oligodendrocytes. The observation that both a stimulatory factor (PDGF-AA) and a regulatory factor (TGF-beta) for O-2A progenitor cell proliferation and differentiation are produced from a single neuronal cell line emphasizes the potential critical interaction between neurons and O-2A progenitor cells in myelination and possibly in remyelination.
PTPATH: a FORTRAN program to calculate pressure:80temperature paths from zoned metamorphic garnets

Abstract Program PTPATH generates and solves systems of simultaneous linear differential equations that relate intensive thermodynamic variables in a heterogeneous chemical system. The program can be used to infer changes in pressure and temperature from changes in the chemical composition of zoned minerals such as garnet where the zoning profiles are generated by reaction mechanisms. The only required input data are the “equilibrium” (i.e. peak metamorphic) compositions of the minerals in the matrix of the rock and the changes in mineral composition along the zoning profile.
Antimicrosomal antibodies: what are they telling us?

Patients with dihydralazine hepatotoxicity have been found to have circulating autoantibodies that react with liver microsomes (anti-liver microsome antibodies) and that are clearly distinct from anti-liver and kidney microsomal antibodies observed in patients with tienilic acid-induced hepatitis and in some patients with autoimmune hepatitis. The authors show that anti-liver microsome antibodies present in the sera of five patients with dihydralazine-induced hepatitis specifically react on immunoblots with a 53 kD protein. They further conclude that this target antigen is the phase I drug metabolizing enzyme termed P-450IA2 based on the following observations: (a) immunoblots of a battery of human liver microsomes produced the identical pattern of relative staining whether the blots were developed with anti-rat P-450IA2 IgG, anti-human P-450IA2 IgG or each of the five patients' sera; (b) P-450IA2 catalytic activity was selectively inhibited when human liver microsomes were preincubated with anti-liver microsome-positive sera; (c) anti-liver microsome-positive sera identified purified human P-450IA2 on immunoblots. Anti-liver microsome antibodies appeared to be specific for dihydralazine hepatitis because they were not present in sera obtained from 28 other patients including patients receiving dihydralazine without a toxic response and patients with other significant liver diseases. Finally, the authors demonstrated that dihydralazine could competitively inhibit catalytic activity characteristic of P-450IA2 in human liver microsomes, suggesting that P-450IA2 may be involved in the metabolism of dihydralazine.
Catecholamine-thyroid hormone interactions in liver and adipose tissue

Abstract The beta effects of catecholamines are potentiated by thyroid hormones in adipose tissue. In the liver of hypothyroid rats there is an elevation in the number of beta-adrenergic receptors and the ability of catecholamines to increase cyclic AMP accumulation. Just the opposite effect is noted in adipose tissue of hypothyroid rats where there is a marked reduction in the ability of beta catecholamines to elevate cyclic AMP. Thyroid hormones do not appear to regulate the number of binding sites for beta adrenergic antagonists in adipose tissue but do affect agonist displacement of antagonist binding. The major influence of thyroid status on cyclic AMP metabolism in rat adipocytes is mediated through regulation of the ability of lipolytic hormones and even guanine nucleotides to activate adenylate cyclase. In neither liver or adipose tissue is there any evidence that thyroid hormones affect adrenoceptor interconversion. Thyroid status did not affect the alpha-I adrenergic stimulation of glycogenolysis in rat hepatocytes or the alpha-I adrenergic inactivation of glycogen synthase and stimulation of phosphatidylinositol turnover in rat adipocytes. There was also no effect of thyroid hormones on alpha-2 adrenergic inactivation of adenylate cyclase in hamster adipocytes. In these tissues thyroid hormones affect beta adrenergic responses without affecting either alpha-I or alpha-2 responses.
The Importance of Calcium in the Control of Salt Intake

There is no doubt that the renin-angiotensin-aldosterone system (RAAS) can have a major influence on salt intake but the conditions used to demonstrate this are rare outside the laboratory. Changes in RAAS activity do not explain the voluntary intake of NaCl solution shown by non-deprived rats or the preference for salty foods shown by humans. As a first attempt to investigate an alternative mechanism, my colleagues and I are studying the effects of dietary calcium on salt appetite. Even though calcium-deprived rats have normal RAAS activity, they show a striking increase in NaCl intake, which can surpass the effects of the most severe manipulations of the RAAS. The physiological mechanism underlying this behavior is unknown but it probably involves an adrenal factor, perhaps corticosterone. Whatever the mechanism, the calcium-deprived rat and other low-renin models of salt intake provide a promising approach to help understand the physiological basis of excess salt consumption by humans.
Eurypterus remipes and E. lacustris (Chelicerata: Eurypterida) from the Silurian of North America

Abstract Although sometimes treated as synonyms, Eurypterus remipes (Fiddlers Green Formation) and Eurypterus lacustris (Williamsville Formation) have usually been considered separate species. Conclusions have often been based on statistical methods used to examine sets of carapace measurements. Here, morphological evidence of the cuticular sculpture of the telson margin and the prominent embayment on the lateral carapace margin supports their status as separate species. These differences are consistent throughout ontogeny and between sexual dimorphs. In the interest of establishing taxonomic stability and of providing standards for comparison of morphology, neotypes have been selected for both E. remipes and E. lacustris. Two new morphological characters from the type A genital appendage and the operculum support a close relationship between E. remipes and E. lacustris. New and earlier evidence suggest that the population representing E. remipes developed into the slightly younger E. lacustris population...
Contrasts in Community Action and Opinion

. Opinion or attitude surveys and observations of people's actions are complementary research tools, but they often provide different results. This was the case where two communities, one rural, one suburban, made waste water management decisions which would promote population growth while survey data indicated that community attitudes were neutral or slightly opposed to population growth. Observation of action, and expanding the range of survey response variation revealed that the structure of both community opinion and action was primarily influenced by small groups of people with very strong feelings favoring and disfavoring population growth. Those with very strong feelings were the ones observed to be acting to promote or retard growth.
Perceived health needs of elderly Mexicans living on the U.S.--Mexico border.

This descriptive study explores the health beliefs of an underserved elderly group to gain insight regarding their self-perceived health needs. Focus groups were conducted with 112 elderly Mexicans living on the U.S.-Mexico border. Participants were asked questions regarding positive aspects of aging, self-perception of health status, and health care service needs. Discussions were tape recorded, transcribed, and translated from Spanish into English. Several themes were identified: Many felt having knowledge gained from life experience and raising a family was positive; participants indicated their overall health status was poor; and they believed it was difficult to access quality health care services. Many participants self-reported that health status depended on socioeconomic status, family support, chronic diseases, and previous lifestyle. These findings can help develop culturally appropriate interventions designed to improve the overall health of the elderly living on the U.S.-Mexico border.
Participatory Learning of Propositional Knowledge

Our objective here is to extend the participatory learning paradigm (PLP) to environments in which we are interested in learning information and knowledge expressed in terms of declarative statements. We first recall the basic idea of participatory learning, which stresses the important role of what is already believed in all aspects of the learning process. We then discuss the representation of declarative-type binary knowledge within Zadeh's framework of approximate reasoning. We look at the approximate reasoning inference mechanism and its capability for weighted propositions. We introduce ideas such as consistency, compatibility, and commitment that are needed for our objective. We then provide a version of the PLP that is appropriate for the task of learning declarative knowledge. Central to this is the new updation algorithm that is introduced. We finally look at the dynamic performance of this framework. A particularly notable feature is the unlearning and then learning that takes place when the external environment changes.
Unraveling the Mechanism of Photoinduced Charge Transfer in Carotenoid-Porphyrin-C60 Molecular Triad.

Photoinduced charge transfer (CT) plays a central role in biologically significant systems and in applications that harvest solar energy. We investigate the relationship of CT kinetics and conformation in a molecular triad. The triad, consisting of carotenoid, porphyrin, and fullerene is structurally flexible and able to acquire significantly varied conformations under ambient conditions. With an integrated approach of quantum calculations and molecular dynamics simulations, we compute the rate of CT at two distinctive conformations. The linearly extended conformation, in which the donor (carotenoid) and the acceptor (fullerene) are separated by nearly 50 A, enables charge separation through a sequential CT process. A representative bent conformation that is entropically dominant, however, attenuates the CT, although the donor and the acceptor are spatially closer. Our computed rate of CT at the linear conformation is in good agreement with measured values. Our work provides unique fundamental understanding of the photoinduced CT process in the molecular triad.
Shopping patterns of the rural consumer: Exploring the relationship between shopping orientations and outshopping

Much attention has been devoted to the taxonomic analysis of the shopping orientations, behavior, and other characteristics of urban and suburban consumers. To a great extent, however, rural consumers have escaped the attention of researchers. Research focusing on this sector is needed because recent studies of outshopping suggest that rural consumers represent a significant force in some retail markets. This article examines rural consumers by developing a taxonomy of shopping-orientation groups. Differences among these groups are analyzed with respect to outshopping behavior, and the strategic implications of the research are discussed.
Coccidial Immunity Studies in Chickens 2. The Dosage of Eimeria Tenella and Time Required for Immunity to Develop in Chickens

Abstract SINCE Johnson (1927) first reported on studies concerning immunity to Eimeria tenella many workers have reported on studies in this field. Tyzzer (1929) and Tyzzer et al. (1932) reported that immunity produced was species specific with no indication of cross-immunity between coccidial species. Most workers have used cultures of E. tenella for immunity studies without trying to alter or attenuate the organisms. Jankiewicz and Scofield (1934) used heat while Waxler (1941) used x-ray to attenuate oocysts of E. tenella for immunization studies. Whether or not attenuation occurred is doubtful since the results obtained might have been due to the death of some of the oocysts; thus reducing the viable dosage of oocysts administered. This report is on work designed to provide information on the dosage, the number of inoculations, and the time required to develop immunity against E. tenella. The criterion used to determine the degree of protection from the …
Health Literacy A Nonissue in the 2000 Presidential Election

Both candidates in the 2000 presidential campaign focused on issues related to health and education as key components of their platforms. Yet the campaign failed to address an emerging problem with...
Reliability of blood pressure measurements: Implications for designing and evaluating programs to control hypertension

Abstract Random fluctuations in blood pressure complicate the design and evaluation of screening and treatment programs. The coefficient of reliability (G) indicates the severity of such fluctuations and is used to correct for their effects. This coefficient is defined as the ratio of variance of individuals' true pressures to the variance of their measured pressures under some specified procedure. To estimate G, a statistical model was developed in which true blood pressure drifts according to a type of diffusion process. Correlations between blood pressure measurements at different examinations up to 18 yr apart in the Framingham Study showed a pattern consistent with the model. For diastolic pressure in males, for example, the two-parameter model explained 94% of the variance among 45 correlations and estimated G for a single reading as 0.67. The model implies that elevations in true blood pressure may decline spontaneously over several years in some hypertensives. The model also shows how the reliability of an average of several readings increases (and random error decreases) with the number and type of replications. For example, 2 measurements at separate visits generate the same reliability (0.80 for diastolic BP inmales) as 6 readings at the same visit. This coefficient can be used to decide how many measurements of blood pressure should be obtained in screening, treatment, and compliance programs, and to refine before-and-after evaluations of such programs by correcting the statistical artifact of regression to the mean.
Unusual Influenza A Viruses in Bats

Influenza A viruses infect a remarkably diverse number of hosts. Two completely new influenza A virus subtypes were recently discovered in bats, dramatically expanding the host range of the virus. These bat viruses are extremely divergent from all other known strains and likely have unique replication cycles. Phylogenetic analysis indicates long-term, isolated evolution in bats. This is supported by a high seroprevalence in sampled bat populations. As bats represent ~20% of all classified mammals, these findings suggests the presence of a massive cryptic reservoir of poorly characterized influenza A viruses. Here, we review the exciting progress made on understanding these newly discovered viruses, and discuss their zoonotic potential.
Rib-sparing internal mammary vessel harvest for microvascular breast reconstruction in 100 consecutive cases.

Background:Using the internal mammary vessels as recipient vessels in free-flap autologous breast reconstruction has become a common practice. However, these vessels are typically accessed by removing a costochondral segment. The purpose of this study was to describe the authors’ rib-sparing techniq
A dynamic view of sex chromosome evolution

Sex chromosomes are derived from ordinary autosomes. The X chromosome is thought to maintain most of its ancestral genes over evolutionary time, whereas its Y counterpart degenerates, owing to its lack of recombination. Genomic analyses of young sex chromosome pairs support this view and have shed light on the evolutionary processes underlying loss of gene function on the Y. Studies of ancestral sex chromosomes, however, have also revealed that the process of sex chromosome evolution can be more dynamic than traditionally appreciated. In particular, ancient Y-chromosomes are characterized not only by a loss of genes relative to the X but also by recurrent gains of individual genes or genomic regions, and they often accumulate genes beneficial to males. Furthermore, X chromosomes are not passive players in this evolutionary process but respond both to their sex-biased transmission and to Y-chromosome degeneration, through feminization and the evolution of dosage compensation.
Preference to home landscape: wildness or neatness?

Abstract This study explores students’ preferences toward natural and wild versus clean and neat residential landscapes using preference survey data. Based on the rating scores of four housing landscape designs, multinomial logit models were used to explore the potential influential factors on people's preferences, especially the wildness or neatness of the home landscape. The results suggest that students in agricultural economics, horticulture, and social sciences are more inclined to choose a neat, well-kept environment around their homes. In contrast, wildlife science students prefer more natural landscapes. This study also found that senior students and students from large cities also prefer well-maintained and artificial landscapes. Also, students who are members of an environmental group, and those whose parents have a better education, are more likely to choose a more natural landscape. The results would provide additional information for planners, developers, engineers, architects and foresters in building more livable communities which are aesthetically appealing but also ecologically sound.
Low Circulating Levels of Insulin-Like Growth Factors and Testosterone in Chronically Institutionalized Elderly Men

Objective: To determine the prevalences of and the associations between hyposomatomedinemia and hypogonadism in healthy young men, healthy old men, and chronically institutionalized old men. Design: Survey with serial blood tests. Setting: Veterans Affairs nursing home and young and old men living in the community. Subjects: Three groups were studied: healthy young men (20–29 years old, n = 32), healthy old men (59–98 years old, n = 30), and chronically institutionalized old men (59–95 years old, n = 112). Measurements: Plasma insulin-like growth factor-I (IGF-I), total testosterone (TT), free testosterone (FT), and plasma insulin-like growth factor-II (IGF-II) were measured. In subjects with low testosterone level, serum luteinizing hormone (LH) was also determined. In a subset of chronically institutionalized old men with low IGF-I, the serum growth hormone (GH) level was analyzed during the first 4 hours of sleep. Results: A low IGF-I level (defined as a value below the lower 2.5 percentile of the comparison group) occurred in 85% of the healthy old men when compared with healthy young men (P < 0.001), in 90% of the chronically institutionalized old men when compared with healthy young men (P < 0.001), and in 26% of the chronically institutionalized old men when compared with healthy old men (P < 0.001). In chronically institutionalized old men with low IGF-I compared with healthy young men, nocturnal peaks of serum GH were <2 ng/mL in most cases. Low TT (defined as a value below the lower 2.5 percentile of the comparison group) occurred in 86% of the healthy old men when compared with healthy young men (P < 0.001), in 88% of the chronically institutionalized old men when compared with healthy young men (P < 0.001), and in 28% of the chronically institutionalized old men when compared with healthy old men (P < 0.001). The results of FT were similar. In 80% of the institutionalized old men with low TT and FT, the serum LH level was low (<20 mU/mL). In 53% of the institutionalized old men, the IGF-II level was below the lower 2.5 percentile of the healthy old men (P < 0.001). In both healthy and institutionalized old men, IGF-I and IGF-II levels were significantly correlated to each other (r = 0.6), but neither was significantly correlated to TT or FT. In the institutionalized old men, IGF-I was inversely correlated with age and with a diagnosis of dementia; TT and FT were inversely correlated with age and with the degree of dependency in ADL's. Conclusions: Compared with healthy young men, most healthy old men have low serum IGF-I, TT, and FT levels. The geriatric hyposomatomedinemia and hypogonadism are more severe in institutionalized old men. In the latter group, both endocrine deficiencies are usually of central origin, but their occurrences are not significantly associated. Healthy old men usually have a low level of IGF-I compared with healthy young men, but a similar level of IGF-II; institutionalized old men are usually low in both values.
Optical beam steering using a liquid-crystal television panel

A blazed grating can be generated using a programmable liquid-crystal television (LCTV) panel. Despite the effects of phase mismatch, phase quantization, and pixel addressing of the panel, optical beam steering is possible, particularly for small angle deflection applications. © 1994 John Wiley & Sons, Inc.
Complete distributional problems, hard languages, and resource-bounded measure

We say that a distribution μ is reasonable if there exists a constant s⩾0 such that μ({x||x|⩾n})=Ω(1/ns). We prove the following result, which suggests that all DistNP-complete problems have reasonable distributions. If NP contains a DTIME(2n)-bi-immune set, then every DistNP-complete set has a reasonable distribution. It follows from work of Mayordomo [19] that the consequent holds if the p-measure of NP is not zero. Cai and Selman [6] defined a modification and extension of Levin's notion of average polynomial time to arbitrary time-bounds and proved that if L is P-bi-immune, then L is distributionally hard, meaning that, for every polynomial-time computable distribution μ, the distributional problem (L,μ) is not polynomial on the μ-average. We prove the following results, which suggest that distributional hardness is closely related to more traditional notions of hardness. 1. If NP contains a distributionally hard set, then NP contains a P-immune set. 2. There exists a language L that is distributionally hard but not P-bi-immune if and only if P contains a set that is immune to all P-printable sets. The following corollaries follow readily 1. If the p-measure of NP is not zero, then there exists a language L that is distributionally hard but not P-bi-immune. 2. If the p2-measure of NP is not zero, then there exists a language L in NP that is distributionally hard but not P-bi-immune.
The role of G protein in muscarinic depolarization near resting potential in cultured hippocampal neurons

Abstract Cultured neurons from the CA1 and CA3 regions of the rat hippocampus were studied by using the whole-cell version of patch clamp. Application of acetylcholine (5–10 μM) or muscarine (20 μM) to a neuron with a holding potential of≈−70mV produced a slow inward current. This inward current was inhibited by atropine (1–2 μM). Loading the cell with GTPγS caused a change in the muscarinic response. In the control cells the muscarine-induced inward current recovered by 89%. On the other hand, in the GTPγS-loaded cells the inward current recovered by only 30%, indicating some irreversibility. Pertussis toxin treatment did not change the muscarine-induced slow inward current. Loading the cells with cyclic AMP (100 μM) plus IBMX (1 mM) (an inhibitor of phosphodiesterase) did not occlude the effect of muscarine. We conclude that the slow inward current is mediated through a pertussis toxin-insensitive G protein, and that cyclic AMP is not a part of the signal transduction cascade. The finding that the GTPγS-loaded cells did not show complete irreversibility was discussed in relation to the results of Benson et al. (J. Physiol., 404 (1988) 479–496), which showed that there are two ionic mechanisms responsible for the muscarine-induced depolarization. Occasionally cells were encountered, in which muscarine (or acetylcholine) evoked a large and rapid inward current, followed by the usual slow inward current. The time course of this rapid response was not affected by GTPγS.
Unexpectedly high radioactivity burdens in ice-rafted sediments from the Canadian Arctic Archipelago.

Abstract Unexpectedly high specific activities of 137 Cs (1800–2000 Bq kg − 1 dry weight) have been detected in fine-grained sediments entrained in multi-year sea ice floes grounded in Resolute Bay near the center of the Northwest Passage through the Canadian Arctic Archipelago. These results are remarkable because: (1) the specific activities are about two orders of magnitude higher than average specific activities detected in previous studies of sea ice rafted sediments from the Arctic Ocean, (2) two independent observations of these unexpectedly high specific activities were made several years apart, (3) the sampling site is on the opposite side of the Arctic basin from potential radioactive sources such as disposal and weapons testing sites of the former Soviet Union and nuclear fuel reprocessing sites in western Europe, and (4) the closest compositional match to known geologic source regions is Banks Island, on the western edge of the Arctic Archipelago, although a smaller number of grains from one of the two samples were mineralogically matched to sediments in the Laptev Sea. Consequently, the sediments are probably not from a single distinct source and were likely mixed during sea ice transport. Coupled with previous observations of higher radionuclide specific activities in some sea ice rafted sediments relative to bottom sediments, these new observations indicate that comparatively high as well as variable radioactive contaminant burdens in ice rafted sediments must be common and geographically independent of proximity to known contaminant sources. The mechanisms that would facilitate these unexpected high radionuclide burdens in sea ice are not known and require additional study, as well as investigations of the implications for the transport and fate of contaminants in Arctic sea ice.