cssi/SciSciGPT-SciSciNet huggingface dataset:
On the Asymptotics of Quantizers in Two Dimensions

When the mean square distortion measure is used, asymptotically optimal quantizers of uniform bivariate random vectors correspond to the centers of regular hexagons (Newman, 1982), and if the random vector is non-uniform, asymptotically optimal quantizers are the centers of piecewise regular hexagons where the sizes of the hexagons are determined by a properly chosen density function (Su and Cambanis, 1996). This paper considers bivariate random vectors with finite?th (?>0) moment. If the?th mean distortion measure is used, a complete characterization of the asymptotically optimal quantizers is given. Furthermore, it is shown that the procedure introduced by Su and Cambanis (1996) is also asymptotically optimal for every?>0. Examples with a normal distribution and a Pearson type VII distribution are considered.
The use of microworlds to study dynamic decision making

Abstract Dynamic decision-making (DDM) research grew out of a perceived need for understanding how people control dynamic, complex, real-world systems. DDM has describable characteristics and, with some unavoidable sacrifice of realism, is suitable for study in a laboratory setting through the use of complex computer simulations commonly called `microworlds'. This paper presents a taxonomic definition of DDM, an updated review of existing microworlds and their characteristics, and a set of cognitive demands imposed by DDM tasks. Although the study of DDM has garnered little attention to date, we believe that both technological advancement and the relationships between DDM and naturalistic decision making, complex problem solving, and general systems theory have made DDM a viable process by which to study how people make decisions in dynamic, real-world environments.
Life in the calcium chloride environment of Don Juan Pond, Antarctica

DON JUAN POND, which contains saturated calcium chloride brine, is in the south fork of the dry Wright Valley of Antarctica at latitude 77°33′S and longitude 167°10′E, and has been controversial almost since its discovery in 1961. Meyer et al.1,2 reported a sparse microflora of four species of heterotrophic bacteria and a yeast. Cameron, Horowitz and colleagues3,4, using the Antarctic dry valleys as the best available natural simulation of Mars, reported that many areas were virtually sterile and, at most, limited to sparse bacterial populations. Field work5–10 has revealed a more abundant and varied microflora of yeasts, blue-green algae, fungi and bacteria, especially in the bottoms of frozen freshwater lakes. However, reports point to an extreme dry valley–exposed rock South-Polar biome consisting predominantly of heterotrophic forms, mainly prokaryotic with occasional fungal associates. If this is correct Don Juan Pond must, like the dry valleys generally, consist only of converter–consumer populations lacking extensive capability for continuous carbon reduction. Cameron has emphasised the ecological restrictions on the activity and distribution of algae in the dry valleys and mentions no algal or other autotrophic forms in his discussion of Don Juan Pond, even though thin organic layers were found 2 m below the 15–20 cm of standing water11. However, in the course of a mercury sampling programme during the austral summer of 1978–79 we observed an extensive, irregular pellicle or mat-like structure 2–5 mm thick but extending 500–600 m2 over much of the western part of the Don Juan Pond salt flats.
Preferential association of nucleolar organizing human chromosomes as revealed by silver staining technique at mitosis.

The frequency of different types of satellite associations of nucleolar organizing human chromosomes (i.e. acrocentric chromosomes; 13, 14, 15, 21, and 22) is reported using 10 normal individuals by Ag-staining technique. The preferential involvement of acrocentric chromosomes in satellite association is suggested. Only acrocentric chromosomes with active NORs (i.e. Ag-stained) were found in association while unstained (inactive NORs) chromosomes were never seen in satellite association. In general as number of NORs expression increase, the frequency of association per cell was also increased. A possible mechanism and the clinical consequences of such an unusual phenophenon is described.
Scenes From Polish Working‐Class Life in Milwaukee, 1900s–1940s

(1994). Scenes From Polish Working‐Class Life in Milwaukee, 1900s–1940s. The Historian: Vol. 57, No. 1, pp. 89-96.
Purification and Characterization Of a Thyroglobulin Reactive Phytoprecipitin From Pisum sativum

Abstract By means of paper curtain electrophoresis and polyacrylaaide gel filtration, it has been possible to isolate the thyroglobulin-reactive phytoprecipitin from pea (Pisum sativum; American pea; Russian pea) extract. An of 4.0 Svedbergs and a of 5.7×10−7 cm2/sec were found from analytical ultracentrifuge experiments and a specific volume of 0.61 was determined by pycnometry. These data yield a molecular weight of 43,000 for the phytoprecipitin and, postulating an oblong ellipsoid shape, an asymmetry factor of 12. Its electro-phoretic mobility corresponds with that of globulin. It could be shown that the phytoprecipitin attaches to the carbohydrate part of the thyroglobulin.
Media depth influences Sedum green roof establishment

Species selection and initial establishment of plants is critical for long term survival and health of green roofs. Plants that can withstand harsh environmental conditions and provide rapid coverage on extensive green roofs can reduce erosion, limit weed invasion, and provide a more aesthetically pleasing roof to satisfy customers. This study evaluated the effect of green roof substrate depth on initial establishment of 12 Sedum species in a Midwestern US climate. Plugs of 12 Sedum species were planted on 8 June 2005 and evaluated bi-weekly until first frost for absolute cover (AC) using a stainless steel point-frame transect. Most species exhibited greater growth and coverage at a depth of 7.0 and 10.0 cm relative to 4.0 cm. AC was highest for Sedum sarmentosum at all depths, but this species may be too aggressive. Other suitable species include Sedum floriferum, Sedum stefco, and Sedum spurium ‘John Creech’. In general, species that are less suitable are Sedum ‘Angelina’, Sedum cauticola ‘Lidakense’, Sedum ewersii, Sedum ochroleucum, and Sedum reflexum ‘Blue Spruce’. For the species tested, a minimum of 7.0 cm is highly recommended. With shallower substrates, S. sarmentosum and S. stefco will provide the fastest coverage.
Influences of Subject Self-Selection on the EEG Alpha-Hypnotizability Correlation

To determine the effect of subject self-selection on the alpha-hypnotizability correlation, the correlations between volunteer and invited subject groups were compared. For 8 volunteers the correlation between baseline eyes-closed occipital alpha and the Harvard Group Scale of Hypnotic Susceptibility score was r=.72; for 12 invited subjects, that correlation was r=-.02. The significant difference in these correlations gives support to a previously published paper which hypothesized, on the basis of a literature review, that sampling modifications generated by subject self-selection were responsible for the occurrence of significant alpha-hypnotizability correlations.
Dissecting Cyclops: a detailed analysis of a multithreaded architecture

Multiprocessor systems-on-a-chip offer a structured approach to managing complexity in chip design. Cyclops is a new family of multithreaded architectures which integrates processing logic, main memory and communications hardware on a single chip. Its simple, hierarchical design allows the hardware architect to manage a large number of components to meet the design constraints in terms of performance, power or application domain.This paper evaluates several alternative Cyclops designs with different relative costs and trade-offs. We compare the performance of several scientific kernels running on different configurations of this architecture. We show that by increasing the number of threads sharing a floating point unit we can hide fairly high cache and memory latencies. We prove that we can reach the theoretical peak performance of the chip and we identify the optimal balance of components for each application. We demonstrate that the design is well adapted to solve problems that are difficult to optimize. For example, we show that sparse matrix vector multiplication obtains 16 GFlops out of 32 GFlops of peak performance.
Sex differences in reporting sensitive behavior: A comparison of interview methods

While telephone surveys generally are considered to be comparable to in-person interviews for the collection of survey data, their utility for the acquisition of sensitive information from respondents remains in question. This paper examines the effect of interview method upon self-reports of a threatening topic—substance use—for male and female college students. It is hypothesized that males may be less likely to admit sensitive behaviors in telephone interviews, compared to face-to-face encounters, due to an interaction of a characteristic of the telephone medium (i.e., the lack of balanced exchange of identifying information between the interviewer and respondent) and aspects of the male sex role, which discourages self-revelation. Findings indicate that differences in reported use of both legal and illegal substances by interview method were greater among males than females. These gender differences in reporting behavior by survey method remained after statistical controls were applied.
Drosophila development pulls the strings of the cell cycle

The three cycles of cell division immediately following the formation of the cellular blastoderm during Drosophila embryogenesis display an invariant pattern. Bursts of transcription of a gene called string are required and sufficient to trigger mitosis at this time during development. The activator of mitosis encoded by the string gene is a positive regulator of cdc2 kinase and a Drosophila homologue of the Saccharomyces pombe cdc25 tyrosine phosphatase. Evidence presented in a recent paper demonstrates that transcription of string, and hence the timing and pattern of mitosis in the postblastoderm embryo, is under complex developmental control. Several lines of evidence support this interpretation, including the analysis of string transcription in pattern formation mutants, cell cycle arrest mutants, and the preliminary characterization of an extensive cis-acting regulatory region.
The physical interaction of nitrogen with Pyrex, stainless steel, and nickel at very low pressure

The physical adsorption of nitrogen on the surfaces of Pyrex, 347 stainless steel, and polycrystalline nickel was investigated over the pressure range 1×10−12–3×10−7 Torr and for the temperatures 77.4 and 87.4 °K. The metal surfaces were prepared by vacuum firing, by chemical cleaning, and, following bakeout, by electron impact desorption (EID). Work function measurements were used to indicate changes in the surface condition following electron bombardment, and a mass spectrometer was used to monitor gas composition. The isotherms revealed that the stainless surface was very heterogeneous and that the Pyrex surface area had a roughness factor of 1.7. Nitrogen isotherms were also taken on the metal surfaces after they had been exposed to oxygen. Very little change in physical adsorption on the nickel was detected, presumably because the chemisorbed oxygen was incorporated into the bulk. The chemical adsorption of N2 on nickel at room temperature and below was not observed.
Effects of environmental manipulation on the locomotor activity and agonistic behavior of cultured juvenile American lobsters, Homarus americanus

The locomotor activity patterns and agonistic encounters of cultured juvenile (IX–XIII stage) American lobsters, Homarus americanus (Milne-Edwards) held in 8 experimental environments were investigated to examine their relative contribution to aggressive level. Three variables: (1) lobsters individually or communally maintained, (2) shelters present or absent, and (3) open or closed seawater system were tested in a set of factorial experiments. Locomotor activity of lobsters held in a 12 h: 12 h light: dark regime was recorded for individually separated lobsters for the first 5 days and for communally held lobsters for the next 5 days of a 10-day experimental period. All lobsters maintained individually had similar levels of activity. When the same individuals were communally maintained, there appeared to be social inhibition of activity. In addition, communally held lobsters without shelter were twice as active as those provided with shelter. The activity levels of groups of communally held lobsters with shelter progressively decreased over the experimental period. All lobsters became somewhat entrained to the light: dark cycle and were nocturnally active. However, the degree of entrainment was strongly influenced (P<0.001) by the presence or absence of shelter and other lobsters. Individually maintained lobsters all showed good entrainment, although those provided with shelter were slightly better entrained. The presence of conspecifics desynchronized activity patterns when shelter was not provided. Aggressive level, as measured by the frequency of agonistic encounters per 15-min observation period and the number and types of displays per encounter, decreased over an 8-day period for groups of 3 lobsters in all experimental environments. Lobsters maintained in a closed system initially showed higher frequencies of agonistic encounters than those held in an open system. The observed decrease in aggressive level with time primarily resulted from decreased activity levels. When two lobsters met, the probability of an agonistic encounter was about 0.8 throughout the experimental period, but decreasing activity levels resulted in progressively fewer encounters. The results suggest several approaches for limiting aggression among communally maintained lobsters in culture systems by environmental manipulation.
CaMKII does it again: even the mitochondria cannot escape its influence.

Although the recent identification of the mitochondrial Ca2+ uniporter (MCU) has resolved a long-standing mystery as to how Ca2+ freely enters the mitochondria, it has also evoked additional questions such as its mode of regulation and the identity of other associated factors. In an article recently published in Nature , Joiner et al1 provide data demonstrating that in the heart, matrix-localized Ca2+/calmodulin-dependent protein kinase II (CaMKII) can upregulate MCU activity in a manner requiring phosphorylation of the channel N terminus. They showed that inhibition of CaMKII-dependent MCU activity protected the heart from ischemic injury by presumably reducing Ca2+ influx and desensitizing the mitochondrial permeability transition pore (MPTP) to opening. Although these results demonstrate convincingly that CaMKII plays an important role in MCU regulation and subsequent response to cardiac injury, several questions remain unanswered. The ability of mitochondria to take up and sequester Ca2+ plays an important role in the buffering of cytosolic Ca2+, regulation of ATP production via the citric acid cycle, and regulation of apoptotic and necrotic cell death pathways.2 Although mitochondrial Ca2+ uptake was first described in the 1960s3 and the electrophysiological properties of the MCU were reported in 2004,4 it was not until 2011 that 2 articles were published revealing the genetic identity of the MCU.5,6 This pioneering work has initiated a search for additional members of the MCU complex (such as MICU17 and the recently discovered MCUR1),8 as well as an attempt to understand how MCU-mediated Ca2+ influx participates in the regulation of whole-cell Ca2+ signaling and whether well-described pathways that regulate other Ca2+ handling processes can similarly modulate MCU-dependent Ca2+ uptake. In the featured article, Joiner et al1 show that CaMKII serves …
Commentary on "Lowering the risk of Alzheimer's disease: evidence-based practices emerge from new research." Prevention of Alzheimer disease.

s P s I s p g c t b a i r r o s i It has been an extraordinarily productive decade for lzheimer Disease (AD) research in many fields ranging rom molecular genetics, neurophysiology and brain imagng, to clinical and epidemiologic studies. In 1997, a review of the current state of the art concluded hat only age and family history could be considered as risk actors for AD with any degree of certainty [1]. Now, as the eview by Jedrziewski et al shows [2], many potential risk actors for AD have been identified, and at least some of hese could be the target for prevention strategies. Two articularly interesting areas not completely addressed in his survey are the rather remarkable and apparent associaion between well-known cardiovascular risk factors, hyperension, diabetes, the metabolic syndrome, and AD risk [3] nd newer studies suggesting a link between stress and AD 4]. Given the enormous and growing burden to society that D represents, both within United States as well as gloally, the idea that there may be available prevention stratgies is a very exciting one. The authors of this survey are, however, suitably cauious in their conclusions emphasizing the need for more esearch before identifying definitive prevention practices nd raise a number of methodologic issues. Some of the problems in interpretation and analysis are xemplified in the survey. For example, the review of indiidual risk factors includes results using different outcomes, e, AD, dementia, and cognitive decline. Although AD pahology is a major cause of dementia and cognitive decline, t is not the only one, particularly in the case of cognitive ecline. So grouping results using these outcomes may lead o somewhat erroneous conclusions regarding the strength f the association specifically with AD. The survey also
The Plastidic Phosphoglucomutase from Arabidopsis. A Reversible Enzyme Reaction with an Important Role in Metabolic Control

An Arabidopsis cDNA (AtPGMp) encoding the plastidic phosphoglucomutase (PGM) predicted a 623-amino acid protein with an N-terminal sequence typical of a plastid signal peptide. Expression of a recombinant protein in Escherichia coli confirmed its enzyme activity. The recombinant enzyme had an apparent K(m) value of 98.5 microM and a V(max) of 4.48 micromol min(-1) (mg protein)(-1). The Calvin cycle intermediates fructose-1,6-bisphosphate and ribulose-1, 5-bisphosphate exerted an inhibitory effect on PGM activity, supporting its proposed involvement in controlling photosynthetic carbon flow. A point mutation was identified in the AtPGMp gene of the Arabidopsis pgm-1 mutant. The mutation in the mutant transcript generated a stop codon at about one third of the wild-type open reading frame, and thus rendered the polypeptide nonfunctional. Storage lipid analysis of the pgm-1 mutant seeds showed a 40% reduction in oil content compared with that of wild type. Our results indicate that plastidic PGM is an important factor affecting carbon flux in triacylglycerol accumulation in oilseed plants, most likely through its essential role in starch synthesis.
Intercultural health and ethnobotany: How to improve healthcare for underserved and minority communities? ☆

Abstract Ethnopharmacological relevance The present conceptual review explores intercultural healthcare—defined as the integration of traditional medicine and biomedicine as complementary healthcare systems—in minority and underserved communities. This integration can take place at different levels: individuals (patients, healers, biomedical healthcare providers), institutions (health centers, hospitals) or society (government policy). Background Contemporary ethnobotany research of traditional medicine has primarily dealt with the botanical identification of plants commonly used by local communities, and the identification of health conditions treated with these plants, whereas ethnopharmacology has focused on the bioactivity of traditional remedies. On the other hand, medical anthropology seems to be the scholarship more involved with research into patients' healthcare-seeking itineraries and their interaction with traditional versus biomedical healthcare systems. The direct impact of these studies on public health of local communities can be contested. Aim of the review To compare and discuss the body of scholarly work that deals with different aspects of traditional medicine in underserved and minority communities, and to reflect on how gaps identified in research can be bridged to help improve healthcare in these communities. Key findings The literature covers a broad range of information of relevance to intercultural healthcare. This information is fragmented across different scientific and clinical disciplines. A conceptual review of these studies identifies a clear need to devote more attention to ways in which research on traditional medicine can be more effectively applied to improve local public health in biomedical resource-poor settings, or in geographic areas that have disparities in access to healthcare. Conclusions Scholars studying traditional medicine should prioritize a more interdisciplinary and applied perspective to their work in order to forge a more direct social impact on public health in local communities most in need of healthcare.
Analyzing performance of large scale parallel systems

The authors study the impact of parallel processing overhead and the degree of concurrency of a parallel algorithm on the optimal number of processors to be used when the criterion for optimality is minimizing the parallel execution time. They evaluate a more general criterion of optimality and show how operating at the optimal point is equivalent to operating at a unique value of efficiency, which is a characteristic of the criterion of optimality and the properties of the parallel system under study. The technical results derived are put in perspective with similar results that have appeared in the literature. It is shown that this study generalizes and/or extends these earlier results. >
COMMUNITY STRUCTURE OF SHORTGRASS-PRAIRIE RODENTS: COMPETITION OR RISK OF INTRAGUILD PREDATION?

Local assemblages of rodents in northern shortgrass prairie may reflect either predatory or competitive effects of northern grasshopper mice (Onychomys leucogaster) on other species such as deer mice (Peromyscus maniculatus). In an effort to distinguish these two types of effects, during the summer of 1994 I compared abundances, patterns of microhabitat use, and diets of P. maniculatus on four areas of shrub-dominated prairie in north-central Colorado to these characteristics on four similar sites where 0. leucogaster was removed. The abundance of P. maniculatus decreased during the study on both control and removal sites, but the decline was greater on controls, where numbers of 0. leucogaster increased. Declines in the abundance of P. maniculatus on individual study plots were correlated with abundances and recolonization rates of 0. leucogaster. Only 6% of P. maniculatus present on controls during pre-removal trapping were captured 7 wk later, compared to 32% of those initially present on removal sites. Furthermore, changes in the number of P. maniculatus were inversely related to the amount of shrub cover on sites, suggesting that shrubs may have provided refuge from 0. leucogaster, which rarely uses these microhabitats. Analyses of microhabitat use support this assertion; individual P. maniculatus increased their use of shrubs on control sites when 0. leucogaster was abundant, but there were no shifts in microhabitat use on removal sites. The proportions of arthropods in the diets of the two species were similar prior to Onychomys removals, and although P. maniculatus consumed fewer arthropods as the experiment progressed, diets did not differ between control and removal sites. In addition, Ord's kangaroo rats (Dipodomys ordii) increased slightly in number following removals, and western harvest mice (Reithrodon- tomys megalotis) colonized two removal sites. These results suggest that predatory or aggressive interference by 0. leucogaster, rather than exploitative competition, was re- sponsible for the observed changes in abundance and microhabitat use. Risk of aggression or predatory interference therefore may influence the local abundance and distribution of P. maniculatus and other small rodents on areas of shortgrass prairie where habitat char- acteristics permit coexistence.
Telomere Length Varies by DNA Extraction Method: Implications for Epidemiologic Research—Letter

In their recent article, Cunningham and colleagues ([1][1]) reported differences in leukocyte telomere length (TL) related to the method of DNA extraction, with shorter TL measurements among samples extracted using QIAamp (Qiagen) compared with those extracted using PureGene or phenol/chloroform
Tissue and Gene Specificity of Mouse Renin Expression

The Ren-1 locus of mice encodes the protease renin, which with converting enzyme processes angiotensinogen to the potent vasopressor angiotensin II. Some strains of mice appear to carry a duplication of the renin structural gene (Ren-2) near the Ren-1 locus. Strains with the gene duplication can exhibit as much as 100-fold higher levels of submaxillary gland renin compared to strains with a single gene copy. In contrast, kidney renin levels appear to be unaffected by the gene duplication. Sequence analysis of a 319 bp renin cDNA recombinant isolated from a kidney library from the two-gene strain DBA/2Ha corresponds to a transcript of the Ren-1 gene. Moreover, a single base substitution of A for G at residue #996 in the kidney renin mRNA creates a potential glycosylation recognition site that may, in part, account for the differential glycosylation of kidney and submaxillary gland renins. In addition, our tissue surveys indicate that mature mRNAs from the Ren loci are detectable in adrenal gland and testes, as well as sublingual and parotid salivary glands, and reveal length variation for the renin transcripts in at least the submaxillary gland.
Neurocognitive development in 22q11.2 deletion syndrome: comparison with youth having developmental delay and medical comorbidities

The 22q11.2 deletion syndrome (22q11DS) presents with medical and neuropsychiatric manifestations including neurocognitive deficits. Quantitative neurobehavioral measures linked to brain circuitry can help elucidate genetic mechanisms contributing to deficits. To establish the neurocognitive profile and neurocognitive 'growth charts', we compared cross-sectionally 137 individuals with 22q11DS ages 8-21 to 439 demographically matched non-deleted individuals with developmental delay (DD) and medical comorbidities and 443 typically developing (TD) participants. We administered a computerized neurocognitive battery that measures performance accuracy and speed in executive, episodic memory, complex cognition, social cognition and sensorimotor domains. The accuracy performance profile of 22q11DS showed greater impairment than DD, who were impaired relative to TD. Deficits in 22q11DS were most pronounced for face memory and social cognition, followed by complex cognition. Performance speed was similar for 22q11DS and DD, but 22q11DS individuals were differentially slower in face memory and emotion identification. The growth chart, comparing neurocognitive age based on performance relative to chronological age, indicated that 22q11DS participants lagged behind both groups from the earliest age assessed. The lag ranged from less than 1 year to over 3 years depending on chronological age and neurocognitive domain. The greatest developmental lag across the age range was for social cognition and complex cognition, with the smallest for episodic memory and sensorimotor speed, where lags were similar to DD. The results suggest that 22q11.2 microdeletion confers specific vulnerability that may underlie brain circuitry associated with deficits in several neuropsychiatric disorders, and therefore help identify potential targets and developmental epochs optimal for intervention.
Private Provision of Infrastructure in Emerging Markets: Do Institutions Matter?

Governments in developing countries have encouraged private sector investment to meet the growing demand for infrastructure. According to institutional theory, the role of institutions is paramount in private sector development. A longitudinal dataset of 40 developing economies between 1990 and 2000 is used to test empirically how different institutional structures affect private investment in infrastructure, in particular its volume and frequency. The results indicate that property rights and bureaucratic quality play a significant role in promoting private infrastructure investment. Interestingly, they also suggest that countries with higher levels of corruption attract greater private participation in infrastructure.
The source, origin and propagation of quenches measured in superconducting dipole magnets

Transitions from the superconducting to normal state at 4.4 and 1.8 K in several model accelerator dipoles were recorded by a fast data acquisition system. The resistive voltage rise in the conductor during the transitions is used to determine accurately the location of the quench source in the magnets and to estimate the axial and turn-to-turn quench velocities. The quench velocity, temperature evolution and energy deposition in the coil were calculated using the program QUENCH and are in reasonable agreement with the data. In the two dipole magnets studied, the transitions almost always occurred in the regions of highest field. In one coil the high field region is in the straight section because the field in this region is enhanced by iron support rings. In the other magnet the high field region is at the end, in the innermost turn of the first layer. Some quenches were preceded by large voltage spikes that can be ascribed to conductor motion. Other quenches do not appear to be associated with any large energy release. Acoustic emission (AE) was monitored during the tests and AE bursts were observed simultaneous with the initial voltage spike. An increased AE signal continued as the quench progressed.
High-Resolution Electron Microscopy of Magnetic Dielectric Oxides in the Bao:TiO2Fe2O3 System

In a recent work on phase equilibria relations in the BaO:Fe2O3:TiO2 system the existence of sixteen ternary compounds was confirmed. Most of the new found compounds apparently have a new structural type. In this work we employed electron diffraction and high-resolution microscopy in attempt to understand the structures of the new compounds. Since the present work was done on the compounds prepared by solid-state reaction, it also provides a correlation with a single-crystal x-ray work on some of the similar compounds prepared by crystallization from a melt.
Minimum Heating Re-Entry Trajectories for Advanced Hypersonic Launch Vehicles

Optimal re-entry trajectories are generated for reusable launch vehicles which minimize: (i) the heat absorbed at the vehicle surface, (ii) the lower surface temperature, and (iii) the heat absorbed by the internal structure. The approach uses the energy state approximation technique and a finite control volume heat transfer code coupled to a flight path integration code. These trajectories are compared to the optimal re-entry trajectory minimizing the integrated convective heat rate to determine which trajectory produces the minimum internal structural temperatures for a given thermal protection system. Three different thermal protection systems are considered: tile, blanket, and metallic.
A numerical modeling study of low-frequency circulation on the West Florida shelf

Abstract A numerical model using the linearized, diagnostic, primitive equations was applied to the West Florida shelf to provide estimates of low-frequency ( The model results coupled with the available data suggest: (1) the inner shelf region shoreward of the 50-m isobath is primarily wind driven; (2) the deeper, southern section of the shelf is strongly influenced by shelf edge processes and intrusions from the Loop Current; (3) the deeper, northern section of the shelf is primarily wind driven; and (4) modeling of shelf edge processes must include the baroclinic component.
On predictive least squares filtering

In this paper, a class of filters based on the Predictive Least Squares principle recently suggested by Rissanen are proposed and studied. The proposed filtering technique provides a consistent estimate of the number of parameters for a Gaussian regression model while still minimizing the accumulated least squares error. Thus, the proposed filters combine model estimation and parameter estimation to provide optimal prediction and estimation. The proposed Predictive Least Squares filtering has potential application for adaptive coding, spectrum estimation, harmonic retrieval and many other digital signal processing areas.
Aging and HIV infection: a comparison between older HIV-infected persons and the general population.

AbstractBackground: As HIV-infected persons age, the relative contribution of HIV infection, combination antiretroviral therapy (cART), and the normal aging process to the frequent comorbidities is unknown.Methods: We prospectively evaluated comorbidities, cardiovascular risk, cognitive function, and anthropomorphic and laboratory parameters of HIV-infected persons aged 50 years and over in two US urban clinics. Results were compared to controls from the National Health and Nutrition Examination Survey (NHANES) matched 1:1 by age, race, gender, smoking status, and body mass index (BMI).Results: We enrolled 122 HIV-infected persons; median age 55 years, 83% male, 57% Caucasian, 39% current smokers, mean BMI 26 kg/m2, and 92% on cART. Compared to controls, HIV-infected persons had a higher prevalence of hypertension (54% vs 38%), hypertriglyceridemia (51% vs 33%), low bone mineral density (BMD) (39% vs 0%), and lipodystrophy and greater receipt of antihypertensive and lipid-lowering medications (all Ps < .0...
2009 Special Issue: Language and cognition

What is the role of language in cognition? Do we think with words, or do we use words to communicate made-up decisions? The paper briefly reviews ideas in this area since 1950s. Then we discuss mechanisms of cognition, recent neuroscience experiments, and corresponding mathematical models. These models are interpreted in terms of a biological drive for cognition. Based on the Grossberg-Levine theory of drives and emotions, we identify specific emotions associated with the need for cognition. We demonstrate an engineering application of the developed technique, which significantly improves detection of patterns in noise over the previous state-of-the-art. The developed mathematical models are extended toward language. Then we consider possible brain-mind mechanisms of interaction between language and cognition. A mathematical analysis imposes restrictions on possible mechanisms. The proposed model resolves some long-standing language-cognition issues: how the mind learns correct associations between words and objects among an astronomical number of possible associations; why kids can talk about almost everything, but cannot act like adults, what exactly are the brain-mind differences; why animals do not talk and think like people. Recent brain imaging experiments indicate support for the proposed model. We discuss future theoretical and experimental research.
Tempo and mode of flower color evolution

UNLABELLED • PREMISE OF THE STUDY Flower color is one of the best-studied floral traits in terms of its genetic basis and ecological significance, yet few studies have examined the processes that shape its evolution across deep timescales. Advances in comparative methods along with larger phylogenies for floral radiations offer new opportunities for investigating the macroevolution of flower color.• METHODS We examined the tempo and mode of flower color evolution in four clades (Antirrhineae, Iochrominae, Loeselieae, Quamoclit) using models that incorporate trait transitions and lineage diversification. Focusing on floral anthocyanin pigmentation, we estimated rates of gain and loss of pigmentation and tested whether these changes occur predominantly through anagenesis or cladogenesis.• KEY RESULTS We found that the tempo of pigment gains and losses varied significantly across the clades and that the rates of change were often asymmetrical, favoring gains over losses. The mode of color shifts tended to be cladogenetic, particularly for gains of color; however, this trend was not significant.• CONCLUSIONS Given that all flowering plants share the same pathway for producing anthocyanins, the marked variation in the tempo of transitions across the four groups suggests differences in the selective forces acting on floral pigmentation. These ecological and physiological factors, together with genetic basis for color, may also explain the bias toward gains of floral anthocyanins. Estimates for cladogenetic and anagenetic rates suggest that color transitions can occur through both modes, although testing their relative importance will require larger datasets.
Changes in Rate-Pressure Product with Physical Training of Individuals with Coronary Artery Disease

The purpose of this study was to evaluate the effect of two factors--progression of coronary artery disease and physical training of individuals with coronary artery disease--on rate-pressure product (RPP). Subjects received a resting ECG and exercise test using the Balke protocol. We established three groups, one Experimental (E, n = 71) and two Control (C-1, n = 26; C-2, n = 24). Subjects in Groups E and C-1 had initial tests confirming coronary artery disease; subjects in Group C-2 had initial tests within normal limits. Subjects in Group E received treatment consisting of regular aerobic exercise with controlled intensity, frequency, and duration. Subjects in Groups C-1 and C-2 received no regular exercise. After a 10- to 12-month period, all subjects received a second resting ECG and exercise test using the Balke protocol. Changes in estimated maximal aerobic capacity (Vo2max), maximal RPP, and submaximal RPP from initial to final tests were analyzed for all groups. Descriptive statistics were done. The lack of significant changes in estimated Vo2max or in RPP in the Control Groups indicated no effect of progression of the disease or testing procedure familiarity. The estimated Vo2max for Group E increased significantly (p less than .01). Rate-pressure product increased significantly (p less than .01) in maximal exercise and decreased significantly (p less than .01) in submaximal exercise. This finding suggests that physiological changes both in exercising skeletal muscle and the myocardium play a role in the symptomatic improvements and increased maximal work capacities in individuals with coronary artery disease after regular aerobic exercise.(ABSTRACT TRUNCATED AT 250 WORDS)
Synthesizing distributed buffer clock trees for high performance ASICs

An integrated design system is presented in this paper for synthesizing high performance clock distribution networks for application to high speed ASICs. An optimal clock skew schedule is determined which provides a set of localized non-zero clock skew values that improve both circuit performance and reliability. These clock skew values together with the functional hierarchy are used to design the topology of the clock distribution network and to determine the minimum clock path delays which satisfy the clock skew schedule. Distributed buffers targeted for CMOS technology are synthesized to emulate the delay values assigned to the individual branches of the clock tree. Maximum errors of less than 2.5% for the delay of the clock paths and 4% for the clock skew between any two registers belonging to the same global data path as compared with SPICE Level-3 are demonstrated for an example circuit. >
Cellular Senescence Requires CDK5 Repression of Rac1 Activity

Cellular senescence is a tumor-suppressive process characterized by an irreversible cell cycle exit, a unique morphology, and expression of senescence-associated beta-galactosidase (SA-beta-Gal). We report here a role for CDK5 in induction of senescent cytoskeletal changes. CDK5 activation is upregulated in senescing cells. The increased activity of CDK5 further reduces GTPase Rac1 activity and Pak activation. The repression of the activity of the GTPase Rac1 by CDK5 is required for expression of the senescent phenotype. CDK5 regulation of Rac1 activity is necessary for actin polymerization accompanying senescent morphology in response to expression of pRb, activated Ras, or continuous passage. Inhibition of CDK5 attenuates SA-beta-Gal expression and blocks actin polymerization. These results point to a unique, nonneuronal role for CDK5 in regulation of Rac1 activity in senescence, illuminating the mechanisms underlying induction of senescence and the senescent shape change.
Epstein-Barr Nuclear Antigen 1 modulates replication of oriP -plasmids by impeding replication and transcription fork migration through the family of repeats

Background: Epstein-Barr virus is replicated once per cell-cycle, and partitioned equally in latently infected cells. Both these processes require a single viral cis-element, termed oriP, and a single viral protein, EBNA1. EBNA1 binds two clusters of binding sites in oriP, termed the dyad symmetry element (DS) and the family of repeats (FR), which function as a replication element and partitioning element respectively. Wild-type FR contains 20 binding sites for EBNA1. Results: We, and others, have determined previously that decreasing the number of EBNA1binding sites in FR increases the efficiency with which oriP-plasmids are replicated. Here we demonstrate that the wild-type number of binding sites in FR impedes the migration of replication and transcription forks. Further, splitting FR into two widely separated sets of ten binding sites causes a ten-fold increase in the efficiency with which oriP-plasmids are established in cells expressing EBNA1. We have also determined that EBNA1 bound to FR impairs the migration of transcription forks in a manner dependent on the number of EBNA1-binding sites in FR. Conclusion: We conclude that EBNA1 bound to FR regulates the replication of oriP-plasmids by impeding the migration of replication forks. Upon binding FR, EBNA1 also blocks the migration of transcription forks. Thus, in addition to regulating oriP replication, EBNA1 bound to FR also decreases the probability of detrimental collisions between two opposing replication forks, or between a transcription fork and a replication fork.
Evaluation of photoelastic stress patterns produced by various designs of bilateral distal-extension removable partial dentures

The results of this study showed that: 1. The design of a retainer with a mesial rest in conjunction with a buccal I-bar or a wrought-wire and cast lingual arm exhibited the most favorable distribution of vertically applied forces. 2. Retainer designs with a distal rest tend to move the clinical crown distally and the root mesially at the apex, resulting in horizontal forces in the bone. 3. Placing rests of distal-extension removable partial dentures more anteriorly provides an axis of rotation that directs applied forces in a more vertical direction. 4. The distal rest in conjunction with circumferential retainers developed greater horizontal forces within the supporting structures.
Bagging very weak learners with lazy local learning

Bagging predictors have shown to be effective especially when the learners used to train the base classifiers are weak. In this paper, we argue that for very weak (VW) learners, such as DecisionStump, OneR, and SuperPipes, the base classifiers built from boostrap bags are strongly correlated with each other. As a result, a simple bagging (SB) predictor built on such VW learners has very little improvement compared to a single classifier trained from the same data. Alternatively, we propose a Local Lazy Learning based bagging approach (L3B), where base learners are trained from a small instance subset surrounding each test instance. More specifically, given a test instance x, L3B first discovers x?s k nearest neighbours, and then applies progressive sampling to the selected neighbours to train a set of base classifiers, by using a given VW learner. At the last stage, x is labeled as the most frequently voted class of all base classifiers. Experimental results on 32 real-world datasets, including two high dimensional gene expression datasets, demonstrate that L3B significantly outperforms SB for building accurate classifier ensemble models for VW learners.
Dispersive Periodic Boundary Conditions for Finite-Difference Time-Domain Method

A dispersive periodic boundary condition (DPBC) is developed for the finite-difference time-domain method to analyze periodic structures with dispersive media on the boundaries of a unit cell. The formulation is based on the auxiliary differential equation (ADE) method with a two-term Debye model and the constant horizontal wavenumber approach. The developed formulation is easy to implement and is efficient in both memory usage and computational time. The validity of this formulation is verified through several numerical examples such as infinite dispersive slab and sandwiched composite frequency selective surface (FSS) structure.
Intercomparison of observed and simulated ice motion for a one year time series

Heat transfer and ice production in the ice-covered seas is controlled to a large extent by ice motion, which is in turn a function of winds and atmospheric boundary layer conditions. While sea-ice models appear to capture the general elements of this interaction, relatively little data have been available to verify model performance or to assess the spatial and temporal variability of ice motion. Several satellite remote sensing instruments provide the capability of detecting ice displacements. In combination with drifting buoy data, it is now possible to create detailed motion fields suitable for studying mesoscale responses of the ice pack to wind forcing. AVHRR, SAR, and drifting buoys have been merged using optimal interpolation techniques to generate daily gridded ice velocity fields for the Beaufort Sea from June 1992 thru July 1993. These motion fields are compared to simulations using a dynamic-thermodynamic ice model with different ice rheologies and heat transfer processes. The motion fields are discussed in terms of responses to various atmospheric synoptic regimes, and sources of differences between observed and simulated motions are considered. The remotely-sensed ice motion fields show seasonal and temporal variability not apparent in the relatively widely-spaced buoy network. Ice velocities and divergence rates agree in general with the simulations. The cavitating fluid and viscous-plastic ice rheologies yield similar drift directions, but can differ substantially in drift speed under strong winds. The overall utility of AVHRR-based ice motion fields is discussed. Possibilities of assimilating the daily motion fields directly into the ice model to assist in refining the thermodynamic portion of the model is described. >
Preventing falls in the geriatric population.

The word “fall” does not usually strike fear in the hearts of most people. But it should. Falls are all too common in the geriatric population, and they have devastating consequences. They are the leading cause of injury and death by injury in adults over the age of 65 years.1 One of 3 community-dwelling older adults falls each year, with 24% of those who fall sustaining serious injuries and 6% sustaining fractures.2 In the year 2000, falls cost the US health care system more than $19 billion, a number that is expected to increase to $54.9 billion by 2020.3 A person who falls may subsequently experience pain, hospitalization, surgical intervention, admission to a nursing home, decreased overall functional ability, poorer quality of life, or a fear of falling.