cssi/SciSciGPT-SciSciNet huggingface dataset:
The molecular clock revisited: the rate of synonymous vs. replacement change in Drosophila.

Rates of synonymous and nonsynonymous substitution were investigated for 24 genes in three Drosophila species, D. pseudoobscura, D. subobscura, and D. melanogaster. D. pseudoobscura and D. subobscura, two distantly related members of the obscura clade, differ on average by 0.29 synonymous nucleotide substitutions per site. D. melanogaster differs from the two obscura species by an average of 0.81 synonymous substitutions per site. Using a method developed by Gillespie, we investigated the variance to mean ratio, or Index of Dispersion, R, of substitutions along the three species' branches to test the fundamental prediction of the neutral theory of molecular evolution, E(R) = 1. For nonsynonymous substitutions, the average R, Ra is 1.6, which is not significantly different from the neutral theory prediction. Only 5 of the 24 genes had significantly large Ra valves, and 12 of the genes had Ra estimates of less than one. In contrast, the Index of Dispersion for synonymous substitutions was significantly large for 12 of the 24 genes, with an average of Rs = 4.4, also statistically significant. These findings contrast with results for mammals, which showed overdispersion of nonsynonymous substitutions, but not of synonymous substitutions. Weak selection acting to maintain codon bias in Drosophila, but not in mammals, may be important in explaining the high variance in the rate of synonymous substitutions in this group of organisms.
Cooperation and Prosperity of the Americas Initiative: Puerto Rico and Opportunities for Increased Partnership, Collaboration, and Stability for the People of the Americas

The U.S. government's efforts to redefine policy toward Latin America, and to counter the image that it is doing little more than fighting drug trafficking, would be boosted if it embraced cooperation with its territory in the Caribbean: Puerto Rico. Despite years of disagreement and distrust between federal and Puerto Rican political leaders, it is time to refocus on how the island's developed infrastructure, educated population, demonstrated patriotism to the United States, and cultural affinity with Latin America can help U.S.–Latin America policy. Puerto Rico is an ideal location from which to send emergency and humanitarian assistance to the region and to establish training centers to assist in building judicial and other democratic institutions in Latin America. As important, federal and local cooperation in the national security sphere will improve economic and social conditions on an island fighting crime and chronic underemployment. Los esfuerzos del gobierno de Estados Unidos para redefinir su politica hacia Latinoamerica mas alla de la lucha contra el trafico de drogas se robustecerian mediante un acuerdo de cooperacion con Puerto Rico, territorio estadounidense en el Caribe. A pesar de los desacuerdos y de la desconfianza que ha habido entre lideres federales y puertorriquenos, es hora de reconsiderar como los atributos emblematicos de la isla, una infraestructura muy desarrollada, una poblacion con alto nivel educativo, un patriotismo hacia Estados Unidos y una afinidad cultural latinoamericana pueden aportar significativamente a la politica latinoamericana de Estados Unidos. Puerto Rico esta ubicado en una zona que permite responder rapidamente a cualquier desastre natural o emergencia en la region y es el lugar idoneo para establecer centros de adiestramiento profesional para fomentar el desarrollo de instituciones democraticas en la region. A su vez, la cooperacion federal ayudara a mejorar la situacion economica y social de una isla que sufre de una alta tasa de criminalidad y de una tasa de desempleo cronicamente alta.
Ballistic Impact of Silicon Carbide with Tungsten Carbide Spheres

Ballistic impact experiments up to 1800 m/s were conducted on six different confined silioon cubides using tungsten carbide spheres. Purtial results of normalized areal density penetrated versus impact veolocity respouse curves are used to suggest comparative ballistic performance potntial as a possible material screening technique and to provide validation data for numerical sinulstions. Complex response curve features are illustrated using an analytic model that captures critical data features. Data suggest an onset velocity above which the damageis no longer contaned, but is contained, but is inertially confined by the surrounding ceramic. Further increases in velocity increase penetration depths, while the impector remains elastic until a critical value is reached where where the impactor deforms inetutically (or shatten). The response curve then transitions to a reduced penctration rate, comparable to those measured in typical depth-of-by both target and penetrator dynamic properties. The data below the penetrator deformation velocity has potentially isolated an impact regime to enable direct measurement of target resistance for fully confined coamimited canmics. Analysis of this using the conceptual framework of cavity expension is discussed in a forthcoming paper.
Compression Limit Algebras

While there is now a large and rapidly growing literature on the study of direct limits of subalgebras of finite dimensional C*-algebras, the focus in almost every paper on the subject has been on systems with embeddings which have *-extensions to the generated C*-algebra. One notable exception is the paper by Power [PI]. The purpose of this note is to extend the study of systems which are not *-extendible and to produce examples which illustrate some new phenomena.
Patch-clamp recordings reveal powerful GABAergic inhibition in dentate hilar neurons

Whole-cell and cell-attached patch-clamp recordings were used to investigate the nature of GABAA receptor-mediated inhibition in the adult rat dentate gyrus in standard 400-microns-thick horizontal slices. In the presence of the glutamate receptor antagonists D-2-amino-5-phosphonovaleric acid and 6-cyano-7-nitroquinoxaline-2,3-dione, whole-cell voltage-clamp experiments with chloride-filled electrodes ([Cl-]in = [Cl-]out) revealed a high degree of spontaneous activity (10-60 Hz) in all hilar neurons (HNs) recorded with access resistances lower than 20 M omega. The events were inward at negative holding potentials, reversed at around the Cl- equilibrium potential, and were completely abolished by the specific antagonists of the GABAA receptor channel picrotoxin and SR-95531 in a reversible manner, indicating that they were spontaneous inhibitory postsynaptic currents (sIPSCs) mediated by GABAA receptors. The majority of the sIPSCs were TTX-insensitive miniature currents resulting from the action potential-independent release of GABA. The 10-90% rise times and the monoexponential decay time constants of the sIPSCs were significantly longer in HNs than those found in neighboring granule cells (GCs). Furthermore, the decay time constant of the hilar sIPSCs was not voltage dependent, contrary to the voltage dependency of the decay time constant of the sIPSCs recorded from GCs. As HNs have longer electrotonic length than GCs do, dendritic filtering may contribute to the kinetic differences. Non-stationary fluctuation analysis showed that whereas the number of channels open at the peak of individual sIPSCs was similar, the single-channel conductances significantly differed between the two cell groups. The 21% smaller single-channel conductance and the existence of electrotonically close GABAergic synapses on HNs indicate that dendritic filtering alone cannot explain the differences between HNs and GCs. The distinct subunit composition of the GABAA receptor channels in HNs and GCs may also be responsible for the altered kinetics of IPSCs in HNs. However, the subunit specific benzodiazepine agonist zolpidem (3 microns) prolonged the monoexponential decay time constants in both HNs and GCs. Thus, differences between the GABAA receptors of the two cell types are not due to a simple all-or-none presence/absence of the alpha 5 subunit.(ABSTRACT TRUNCATED AT 400 WORDS)
CLINICAL FEATURES, DIAGNOSIS AND TREATMENT OF TUBERCULOSIS IN INFANTS

OBJECTIVE: Despite the recent resurgence of tuberculosis among children in the United States, no series of infants < 1 year of age with tuberculosis has been reported in the last 20 years. This study was undertaken to describe the epidemiology, clinical, and radiographic manifestations, and response to therapy in infants < 1 year of age with tuberculous disease. METHODS: The medical records were reviewed for all infants age 12 months or less with a diagnosis of tuberculosis and cared for at the Children's Tuberculosis Clinic at Ben Taub General Hospital in Houston, Texas between January 1, 1985 and June 30, 1992. RESULTS: Of the 47 infants identified, 51% were female. The median age at diagnosis was 8 months (range 3.5 to 12 months). Fifty-one percent of the infants were African-American and over one-third were Hispanic. All patients were born in the United States. Diagnosis resulted from the examination of an ill infant in 79% of cases, a case contact investigation of an adult suspected of having tuberculosis in 19%, and routine tuberculin skin testing in 2%. An adult with infectious tuberculosis who had contact with the infant was identified in 68% of cases. Intrathoracic disease alone was present in 70% of cases. Fourteen (30%) infants had extrapulmonary tuberculosis (11 central nervous system disease, 2 disseminated disease, and 1 cervical adenitis). Gastric aspirate cultures yielded Mycobacterium tuberculosis from 75% of the infants with isolated intrathoracic disease. Forty-five infants successfully completed therapy and only one death was directly related to tuberculosis. Forty-eight percent of the infants with pulmonary tuberculosis were treated with a 6-month regimen consisting of isoniazid and rifampin supplemented during the first 2 months by pyrazinamide. Eighteen infants received some twice weekly directly observed therapy mainly due to documented or suspected nonadherence. Treatment was well-tolerated; one patient (2%) developed hepatotoxicity due to isoniazid. No infant had a relapse or recurrence of disease in 6 months to 7 years follow-up for a median of 3 years (range, 6 months to 7 years). CONCLUSION: Most infants with tuberculosis are symptomatic at the time of diagnosis, and bacteriologic confirmation was obtained in 70% of cases. A contact investigation of the household should be initiated immediately when an infant is suspected of having tuberculosis because valuable information needed to establish the diagnosis and guide therapy in the infant may be obtained. Intensive 6-month and twice weekly directly observed therapy appear to be well-tolerated and effective for the treatment of pulmonary tuberculosis in infants.
CHACOAN AND VERNACULAR ARCHITECTURE AT AZTEC RUINS: PUTTING CHACO IN ITS PLACE

Aztec Ruins is a classic Chacoan outlier. The two major great houses have classic Chacoan architecture and masonry attributes, alongside vernacular architecture that is more typical o f the San Juan area. Most intriguing are attributes that are not easily categorized as either local or nonlocal, suggesting a mixed group of people participating in great-house construction. Our interpretation supports aspects of both Chacoan immigration and local emulation at Aztec. We believe that Chaco Canyon provided leadership and skilled craftsmen who collaborated with local residents, unlike many outliers where emulation by local populations seems to outweigh Chacoan immigration and control.
Challenges and Opportunities for Electronic Resources (ER) Librarians in Facing Down the Digital Divide

SUMMARY The electronic resources (ER) librarian has a social responsibility to be knowledgeable about the digital divide. Discourse on the digital divide began in the mid-1990s and continues today. Data analysis reveals that divides still exist, particularly when considering income, education, region, disability, age, and race. Librarians face many challenges to take on the digital divide. These challenges include issues of access, content, technical literacy, privacy, civic participation, education, employment, non-use, and political debate. Yet for each challenge, there is an opportunity for the ER librarians to thrive while they face down the digital divide.
Power System Control

The sections in this article are 1 The Control Problem 2 Governor Control System 3 Control Areas and Supplementary Control 4 Constrained Dispatch of Generation 5 Power Pools and Energy Management Systems 6 Deregulation 7 Facts 8 Emerging Power Control Issues
Response to: ‘Is rituximab effective for IgG4-related disease in the long term? Experience of cases treated with rituximab for 4 years’ by Yamamoto et al

We thank Yamamoto and colleagues1 for their response to our paper2 and their description of their experience with rituximab (RTX) in IgG4-related disease (IgG4-RD) in three patients. Their letter raises a number of important points pertaining to the management of IgG4-RD, in general, and to the use of B-cell-depletion strategies, specifically. First, their patients are exemplary of the fact a sizeable subset of IgG4-RD patients has a propensity to disease relapse over time. This point has been underappreciated from early reports of the use of glucocorticoids to treat IgG4-RD because those reports were characterised by short follow-up periods. Although the great majority of patients respond to glucocorticoids initially, repeated disease flares are the rule for many. Second, patients with IgG4-RD endure substantial morbidity from the requirement for repeated courses (or continuous on treatment) with glucocorticoids. The three patients described by Yamamoto and colleagues are reported to have experienced bilateral avascular necrosis of the hips and glucose intolerance (severe diabetes mellitus in one case). Our general sense is that the toxicities of prolonged glucocorticoid use in this and other diseases are underestimated. Moreover, patients …
Gelation behavior of near‐zero shrinkage polybenzoxazines

A new class of phenolic thermosetting resins is developed that is based on the ring-opening polymerization of a benzoxazine precursor. These new materials seek to combine the thermal properties and flame retardance of phenolics with the mechanical performance and molecular design flexibility of advanced epoxy systems. These materials overcome many of the traditional shortcomings of conventional novolac and resole-type phenolic resins, while retaining their benefits. The viscoelastic behavior of the polybenzoxazines during isothermal cure is monitored by dynamic mechanical analysis. Isochronic measurements show that although the aniline-based benzoxazine has a lower activation energy for the gelation process than the methylamine-based resin, it has a slower rate of reaction. The purified monomer and as-synthesized precursor for each benzoxazine are found to polymerize by the same mechanism, despite the absence of an initiating species in the purified resins. The chemical gelation phenomenon of the methylamine-based resin is probed by a multifrequency dynamic cure analysis that allows determination of the instant of chemical gelation, as well as the network relaxation exponent, n. The constant value of the exponent regardless of cure temperature demonstrates that chemical gelation is, in fact, an isoconversion event for the methylamine-based benzoxazine. The multifrequency and isochronic analyses are shown to produce very similar gel times and activation energies for the gelation process.
Toxoplasma gondii: Stable Complementation of sag1 (p30) Mutants Using SAG1 Transfection and Fluorescence-Activated Cell Sorting

Toxoplasma gondii and the related Apicomplexan protozoan pathogens, Plasmodium, Cryptosporidium, and Eimeria, are obligate intracellular parasites which cause severe disease in their hosts. The recent development of transient transfection of Toxoplasma permits the development of strategies utilizing "reverse genetics" to identify molecules critical to parasite survival within the host. We have utilized transfection of Toxoplasma tachyzoites to stably complement a sag1 (or p30) mutant that does not make detectable SAG1. Transfection of mutants with the wild-type SAG1 gene resulted in transient expression of SAG1 in approximately 15-20% of the transfected population. Stable transformants were enriched by repeated sorting of live parasites using a fluorescein-labeled monoclonal antibody specific for SAG1. Cloned recombinant parasites expressed SAG1 at wild-type levels and maintained expression for over 5 months after transfection (approximately 300 divisions). Cloned transformants (which proved to be siblings) carried both the mutated gene and one copy of the transfected gene which had inserted randomly into the Toxoplasma genome.
Binary total pressure measurements for methanol with 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, 2-methyl-2-butanol, 3-methyl-1-butanol, and 3-methyl-2-butanol at 313.15 K

Total pressure measurements at 313.15 K are reported for binary systems of methanol with each of seven pentanol isomers: 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, 2-methyl-2-butanol, 3-methyl-1-butanol, and 3-methyl-2-butanol. The results were obtained using a Van Ness apparatus and were fitted to the four-suffix Margules equation using Barker`s method. The four-suffix Margules equation represents the data to within an average of approximately 0.02 kPa.
SNR estimation and jamming detection techniques using wavelets

An SNR estimation approach and a jamming detector based on wavelet transform theory are presented. The SNR estimator is an in-service, non-data-aided estimator that operates on M-PSK and QAM modulated signals transmitted over baseband CWGN channels. The signal and noise power are separated through a non-linear wavelet technique known as denoising. Two wavelet-based estimators are presented. The first method uses hard-thresholding which extracts the amplitude trend over one or several symbol periods, depending on whether the modulation is constant or multi-level envelope. The second method uses adaptive soft-thresholding and applies a self-similarity criterion between the signal and wavelet. A SNR Moments estimator was also developed as a reference for evaluation purposes. A jamming detector based on discontinuity recognition using wavelets is presented. The detector is implemented for constant-envelope modulation schemes, leaving the multi-level case for future research.
Variational problems for systems having delay in the control action

This paper contains a brief description of the modifications which need to be made in the theory of optimal control for systems modeled by ordinary differential equations if the model contains terms which depend on the previous history of the system state and control actions.
N-terminal acetyltransferases and sequence requirements for N-terminal acetylation of eukaryotic proteins.

Abstract Nα-terminal acetylation occurs in the yeast Saccharomyces cerevisiae by any of three N-terminal acetyltransferases (NAT), NatA, NatB, and NatC, which contain Ard1p, Nat3p and Mak3p catalytic subunits, respectively. The N-terminal sequences required for N-terminal acetylation, i.e. the NatA, NatB, and NatC substrates, were evaluated by considering over 450 yeast proteins previously examined in numerous studies, and were compared to the N-terminal sequences of more than 300 acetylated mammalian proteins. In addition, acetylated sequences of eukaryotic proteins were compared to the N termini of 810 eubacterial and 175 archaeal proteins, which are rarely acetylated. Protein orthologs of Ard1p, Nat3p and Mak3p were identified with the eukaryotic genomes of the sequences of model organisms, including Caenorhabditis elegans, Drosophila melanogaster, Arabidopsis thaliana, Mus musculus and Homo sapiens. Those and other putative acetyltransferases were assigned by phylogenetic analysis to the following six protein families: Ard1p; Nat3p; Mak3p; CAM; BAA; and Nat5p. The first three families correspond to the catalytic subunits of three major yeast NATs; these orthologous proteins were identified in eukaryotes, but not in prokaryotes; the CAM family include mammalian orthologs of the recently described Camello1 and Camello2 proteins whose substrates are unknown; the BAA family comprise bacterial and archaeal putative acetyltransferases whose biochemical activity have not been characterized; and the new Nat5p family assignment was on the basis of putative yeast NAT, Nat5p (YOR253W). Overall patterns of N-terminal acetylated proteins and the orthologous genes possibly encoding NATs suggest that yeast and higher eukaryotes have the same systems for N-terminal acetylation.
Wind-fetch dependence of Seasat scatterometer measurements

This work is focused on the effects of large-scale wind-generated gravity waves on scatterometer wind-measurement accuracy. Theoretical and experimental evidence of the important role played by the degree of wind-wave coupling in surface geometry and therefore in microwave signatures is presented. Seasat scatterometer wind-measurement errors are analyzed, and an error bias is found to be related to the degree of wind-wave development. Attention is focused on a dynamic measure of wind-wave development that characterizes the rate of energy transfer from the mean wind to the energy-carrying portion of the wave spectrum. An explanation of the bias is suggested based on the consideration of an additional component of surface scattering caused by electromagnetic-wave diffraction at the crests of individual, sufficiently steep wavelets.
Path Planning of Spatial Rigid Motion with Constrained Attitude

This paper presents a general quadratic optimization methodology for autonomous path planning of spatial rigid motion with constrained attitude. The motion to be planned has six degrees of freedom and is assumed under constant velocity in the body frame. The objective is to determine the motion orientation (or attitude), handled as control variables, along the planned paths. A procedure is discussed to transform the rotational constraints and attitude constraints as quadratic functions in terms of unit quaternions, and the path-planning problem is reformulated as a general, quadratically constrained, quadratic programming problem. A semidefinite relaxation method is then applied to obtain a bound on the global optimal value of the nonconvex, quadratically constrained, quadratic programming problem. Subsequently, an iterative rank minimization approach is proposed to find the optimal solution. Application examples of aircraft path-planning problems are presented using the proposed method and compared with ...
Intact acute cardiorenal and humoral responsiveness following chronic subcutaneous administration of the cardiac peptide BNP in experimental heart failure.

Background: BNP is a cardiac peptide with vasodilating, lusitropic and natriuretic properties mediated by the second messenger cGMP. We have previously shown that chronic subcutaneous (SQ) administration of BNP in experimental CHF resulted in improved haemodynamics and unloading of the heart. However, it is unknown if this will lead to the development of tolerance to exogenous BNP. Methods: The current study extends our previous study and compares the cardiorenal effects of acute administration of SQ BNP (5 μg/kg) in a group of dogs (n = 5) with rapid ventricular pacing induced CHF (180 bpm for 10 days) to a separate group of CHF dogs (n = 6), who received chronic SQ BNP (5 μg/kg) three times a day for 10 days. Results: Acute administration of SQ BNP resulted in similar increases in both plasma cGMP (35 ± 5 vs. 29 + 2 pmol/ml) and urinary cGMP excretion (UcGMPV) (6000 ±1000 vs. 4000 ± 600 pmol/min) in both the Chronic SQ BNP treated and the Untreated CHF groups (P>0.05). These were associated with decreased cardiac filling pressures and increased urine flow, which were also similar in both groups. Conclusion: In experimental CHF, chronic SQ BNP administration did not result in the development of tolerance as demonstrated by increases in both plasma cGMP and UcGMPV following acute administration of SQ BNP. This may have important clinical implications, suggesting that chronic BNP administration does not lead to the development of tolerance to acute BNP administration.
On paving matroids and a generalization of MDS codes

Abstract We define a class of codes that corresponds to a class of matroids called paving matroids. This class of codes includes maximum-distance-separable (MDS) codes, and some other interesting codes such as the (12,6) ternary Golay code. Some basic properties of these codes are established using techniques from matroid theory. Our results raise a natural existence question to which we obtain partial answers using known results about the non-existence of Steiner systems of the type S(t–1,t,2t).
Improved survival in very short small bowelof infancy with use of long-term parenteral nutrition

Thirteen children with very short small bowel (≤38 cm jejunoileum) beginning in the first month of life were enrolled in a home parenteral nutrition program between 1977 and 1984. Their survival is compared with the collective reported experience with short bowel syndrome before 1972: nine (69%) of 13 have survived, compared with seven (23%) of 30 previously. Five discontinued parenteral nutrition after periods of 4 to 32 months of therapy, and have normal growth and development. Two still receive partial (50% and 60%) parenteral nutrition after 9 and 55 months, respectively, and two still receive total parenteral nutrition after 66 and 68 months of therapy, respectively; all four infants have grown normally, and three are developmentally normal. In the combined categories of 15 to 38 cm jejunoileum without the ileocecal valve and
Subjective Evaluation of Articulatory Effort

Thirty-two adult speakers repeated pairs of CV syllables, each embedded in a carrier phrase, and designated the consonant member of the pair they believed required more articulatory effort. The tas...
Chaotic Dynamics of Driven Flux Drops: A Superconducting ''Dripping Faucet''

When a current is applied to a type-I superconducting strip containing a narrow channel across its width, magnetic flux spots nucleate at the edge and are then driven along the channel by the current. These flux "drops" are reminiscent of water drops dripping from a faucet, a model system for studying low-dimensional chaos. We use a novel high-bandwidth Hall probe to detect in real time the motion of individual flux spots moving along the channel. Analyzing the time series consisting of the intervals between successive flux drops, we find distinct regions of chaotic behavior characterized by positive Lyapunov exponents, indicating that there is a close analogy between the dynamics of the superconducting and water drop systems.
MOLECULAR ABNORMALITIES OF MDM-2 IN HUMAN SARCOMAS

MDM-2 is an oncoprotein that seems to function, at least in part, by interacting with the p53 protein and modulating its tumor-suppressing activity. The MDM-2 gene codes for p57, p74, p76, p85, and p90 proteins. Overexpression of only the p90 MDM-2 protein has been reported in sarcomas showing MDM-2 gene amplification. In addition, post-transcriptional mechanisms have been demonstrated to play a role in the expression of MDM-2 proteins. We investigated MDM-2 gene amplification, mRNA and protein levels in various cases of sarcomas. We found MDM-2 gene amplification in 12 (26%) of 46 cases of sarcoma: 11 of 13 cases of liposarcoma and 1 of 6 cases of malignant fibrous histiocytoma. The MDM-2 amplification correlated with the presence of elevated levels of mRNA and protein in the liposarcomas. In sarcomas other than liposarcomas, mRNA was overexpressed in 7 (30%) of 23 cases, without MDM-2 amplification. In 15 (62.5%) of 24 cases of sarcoma and in 1 case of lipoma the MDM-2 protein was overexpressed as shown by Western blot analysis. Interestingly, p57 not p90 was the most commonly overexpressed MDM-2 protein. These data indicate that the molecular abnormalities affecting MDM-2 expression in cases of sarcoma include transcriptional, post-transcriptional, and gene dosage (amplification) mechanisms. Furthermore, our findings suggest that MDM-2 p57 protein may be as important as p90 in the pathogenesis of human sarcomas.
Efficient scene simulation for robust monte carlo localization using an RGB-D camera

This paper presents Kinect Monte Carlo Localization (KMCL), a new method for localization in three dimensional indoor environments using RGB-D cameras, such as the Microsoft Kinect. The approach makes use of a low fidelity a priori 3-D model of the area of operation composed of large planar segments, such as walls and ceilings, which are assumed to remain static. Using this map as input, the KMCL algorithm employs feature-based visual odometry as the particle propagation mechanism and utilizes the 3-D map and the underlying sensor image formation model to efficiently simulate RGB-D camera views at the location of particle poses, using a graphical processing unit (GPU). The generated 3D views of the scene are then used to evaluate the likelihood of the particle poses. This GPU implementation provides a factor of ten speedup over a pure distance-based method, yet provides comparable accuracy. Experimental results are presented for five different configurations, including: (1) a robotic wheelchair, (2) a sensor mounted on a person, (3) an Ascending Technologies quadrotor, (4) a Willow Garage PR2, and (5) an RWI B21 wheeled mobile robot platform. The results demonstrate that the system can perform robust localization with 3D information for motions as fast as 1.5 meters per second. The approach is designed to be applicable not just for robotics but other applications such as wearable computing.
Misconstrued land use in Vohibazaha: participatory planning in the periphery of Madagascar's Mantadia National Park

Abstract At the end of the 1996–1997 farming season, several groups of farmers were expelled from land inside the Mantadia National Park in eastern central Madagascar, leaving them struggling to salvage meager harvests from fields within the village's oldest cultivated lands. This paper examines the roots of this crisis, examining the history of traditional land-use practices as mediated by relations with national and international institutions. Drawing on concepts recently elaborated in the political ecology and common property literature, the paper demonstrates how the crisis was avoidable, and explores the possibilities for more productive co-management arrangements.
Physical education class injuries treated in emergency departments in the US in 1997-2007.

Objective: The goal was to describe the epidemiological features of physical education (PE)-related injuries treated in US emergency departments. Methods: A retrospective analysis was conducted with data for children and adolescents (5-18 years of age) from the National Electronic Injury Surveillance Study of the US Consumer Product Safety Commission, from 1997 through 2007. Sample weights provided by the National Electronic Injury Surveillance System were used to calculate national estimates of PE-related injuries. Trend significance of the number of PE-related injuries over time was analyzed by using linear regression analysis. Results: An estimated 405305 children and adolescents were treated in emergency departments for PE-related injuries. The annual number of cases increased 150% during the study period (P = .001). Nearly 70% of PE-related injuries occurred during 6 activities, that is, running, basketball, football, volleyball, soccer, and gymnastics. Boys' injuries were more likely to involve the head, to be diagnosed as a laceration or fracture, to be attributable to contact with a person or structure, and to occur during group activities. Girls' injuries were more likely to involve the lower extremities, to be strains and sprains, to be acute noncontact injuries, and to occur during individual activities. Conclusion: More research is needed to identify the cause of the increase in PE-related injuries, to examine the gender difference in PE-related injuries, and to determine appropriate injury prevention solutions and policies. Language: en
Considering evolutionary processes in the use of single-locus genetic data for conservation, with examples from the Lepidoptera

The increasing popularity of molecular taxonomy will undoubtedly have a major impact on the practice of conservation biology. The appeal of such approaches is undeniable since they will clearly be an asset in rapid biological assessments of poorly known taxa or unexplored areas, and for discovery of cryptic biodiversity. However, as an approach for diagnosing units for conservation, some caution is warranted. The essential issue is that mitochondrial DNA variation is unlikely to be causally related to, and thus correlated with, ecologically important components of fitness. This is true for DNA barcoding, molecular taxonomy in general, or any technique that relies on variation at a single, presumed neutral locus. Given that natural selection operates on a time scale that is often much more rapid than the rates of mutation and allele frequency changes due to genetic drift, neutral genetic variation at a single locus can be a poor predictor of adaptive variation within or among species. Furthermore, reticulate processes, such as introgressive hybridization, may also constrain the utility of molecular taxonomy to accurately detect significant units for conservation. A survey of published genetic data from the Lepidoptera indicates that these problems may be more prevalent than previously suspected. Molecular approaches must be used with caution for conservation genetics which is best accomplished using large sample sizes over extensive geography in addition to data from multiple loci.
Light-pressure force in N-atom systems.

An analytical description of long-range collisions between atoms in a laser cooling field is developed. We begin by considering an N-atom master equation. In the regime of low atomic densities (i.e., where the mean distance between two atoms is much larger than the laser wavelength) it is possible to treat the atom-atom interactions in perturbation theory. Furthermore we assume temperatures which allow a semiclassical treatment of the cooling process. The effect of the presence of other atoms can be separated analytically into two parts; an attenuation force due to the absorption of the laser beams in the atomic cloud similar to the results of Dalibard [Opt. Commun. 68, 203 (1988)], which tends to compress the atomic cloud, and a two-atom force due to photon emission and absorption cycles between different atoms. This force proves to be repulsive for the configurations studied and prevents the cloud from collapsing. The result for the first-order perturbation expansion in collision strength generalizes the model proposed by Walker, Sesko, and Wieman [J. Opt. Soc. B 8, 946 (1991)] by including additional terms, such as those associated with Raman couplings.
Curcumin Decreases Amyloid-β Peptide Levels by Attenuating the Maturation of Amyloid-β Precursor Protein

Alzheimer disease (AD) is a devastating neurodegenerative disease with no cure. The pathogenesis of AD is believed to be driven primarily by amyloid-β (Aβ), the principal component of senile plaques. Aβ is an ∼4-kDa peptide generated via cleavage of the amyloid-β precursor protein (APP). Curcumin is a compound in the widely used culinary spice, turmeric, which possesses potent and broad biological activities, including anti-inflammatory and antioxidant activities, chemopreventative effects, and effects on protein trafficking. Recent in vivo studies indicate that curcumin is able to reduce Aβ-related pathology in transgenic AD mouse models via unknown molecular mechanisms. Here, we investigated the effects of curcumin on Aβ levels and APP processing in various cell lines and mouse primary cortical neurons. We show for the first time that curcumin potently lowers Aβ levels by attenuating the maturation of APP in the secretory pathway. These data provide a mechanism of action for the ability of curcumin to attenuate amyloid-β pathology.
Effect of variables and their interactions on RFID tag readability on a conveyor belt — Factorial analysis approach

Radio Frequency Identification (RFID) is an identification system used to create an automated tracking solution to provide real time inventory visibility, operational status, movement of assets through the supply chain. The problem with successful RFID implementation is the lack of application specific optimization. In a packaging environment the variation in product, speed of conveyor, tag position, distance of tag from antenna cannot be generalized. To gain optimum performance from an RFID system these factors should be optimized. The aim of this study is to investigate the relationship between speed of the conveyor belt, type, orientation and placement of the tag. Full factorial and fractional factorial designs are considered to determine the effect of critical factors and the interaction between them based on tag readability. Recommendations are provided for the combinations of the potential factors and their levels in order to obtain the best possible readability.
On the analysis of the thermal line shift and thermal line width of ions in solids

Abstract A method of analysis for the thermally induced line shift and line width of spectral lines regarding the Raman process of ions in solids utilizing rational approximations for the Debye functions is presented. The 2 E level unsplit R-line in V 2+ :MgO is used as an example to illustrate the utility of the methods discussed here in providing a new analytical tool for researchers.
On the equivalence of mode decomposition and mixed finite elements based on the Hellinger—Reissner principle: part I: theory

Abstract A theorem is presented which defines the conditions under which an equivalent mixed finite element based on the Hellinger-Reissner principle exists for a given mode decomposition element. Mode decomposition elements are a family of elements in which parasitic stresses are removed by a suitable projection to enhance the rate of convergence of elements which tend to lock; so far they were outside of any standard finite element formulation. Elements that, by virtue of this theorem, are found equivalent to appropriate mixed elements can be then analyzed by techniques which exist within the framework of Hellinger-Reissner formalism.
Stack Aware Threshold Voltage Assignment in 3-D Multicore Designs

Due to the inherent nature of heat flow in 3-D integrated circuits, stacked dies exhibit a wide range of thermal characteristics. The temperature of dies progressively increases with increasing distance from the heat sink. This heterogeneous temperature profile coupled with the strong dependence of leakage on temperature and process variation plays havoc in achieving system level energy efficiency in such systems, complicating the task of power provisioning in 3-D multicores. In this paper, we address this power provisioning challenge in 3-D ICs by advocating a novel stack aware microprocessor design paradigm, where the circuit designers are aware of the intended placement of a die in a 3-D stack. We present a concrete application of this paradigm through a stack aware threshold voltage (Vt) assignment algorithm for a 3-D multicore system, where we specifically account for: 1) the change in the role of leakage power; 2) expected operating frequency; and 3) dependency of PV induced leakage variation and Vt levels. Our stack aware scheme tunes Vt assignment based on the vertical placement of the die in a 3-D stack. Detailed simulation based experiments with our proposed algorithm show 4%-19% improvement in energy efficiency for a typical multicore system organized as 3-D stacked dies.
Phase-Field Modeling on Morphological Landscape of Isotactic Polystyrene Single Crystals

Spatio-temporal growth of isotactic polystyrene single crystals during isothermal crystallization has been investigated theoretically based on the phase field model by solving temporal evolution of a nonconserved phase order parameter coupled with a heat conduction equation. In the description of the total free energy, an asymmetric double-well local free energy density has been adopted to represent the metastable melt and the stable solid crystal. Unlike the small molecule systems, polymer crystallization rarely reaches thermodynamic equilibrium; most polymer crystals are kinetically stabilized in some metastable states. To capture various metastable polymer crystals, the phase field crystal order parameter at the solidification potential has been treated to be supercooling dependent such that it can assume an intermediate value between zero (melt) and unity (perfect crystal), reflecting imperfect polycrystalline nature of polymer crystals. Two-dimensional simulations exhibit various single crystal morphologies of isotactic polystyrene crystals such as faceted hexagonal patterns transforming to nonfaceted snowflakes with increasing supercooling. Of particular interest is that heat liberation from the crystallizing front influences the curvature of the crystal-melt interface, leading to directional growth of lamellar tips and side branches. The landscape of these morphological textures has been established as a function of anisotropy of surface energy and supercooling. With increasing supercooling and decreasing anisotropy, the hexagonal single crystal transforms to the dense lamellar branching morphology in conformity with the experimental findings.
Labels vs. Pairwise Constraints: A Unified View of Label Propagation and Constrained Spectral Clustering

In many real-world applications we can model the data as a graph with each node being an instance and the edges indicating a degree of similarity. Side information is often available in the form of labels for a small subset of instances, which gives rise to two problem settings and two types of algorithms. In the label propagation style algorithms, the known labels are propagated to the unlabeled nodes. In the constrained clustering style algorithms, known labels are first converted to pair wise constraints (Must-Link and Cannot-Link), then a constrained cut is computed as a tradeoff between minimizing the cut cost and maximizing the constraint satisfaction. Both techniques are evaluated by their ability to recover the ground truth labeling, i.e. by 0/1 loss function either directly on the labels or on the pair wise relations derived from the labels. These two fields have developed separately, but in this paper, we show that they are indeed related. This insight allows us to propose a novel way to generate constraints from the propagated labels, which our empirical study shows outperforms and is more stable than the state-of-the-art label propagation and constrained spectral clustering algorithms.
On some electromagnetic phenomena in the tether magnetoplasma cloud

The tethered satellite system (TSS) will be accompanied by a variety of electromagnetic phenomena. An independent interconnected formation, a «tethered magnetoplasma cloud» (TMC), moving in space along the orbit of TSS, at an altitude of about 300 km, will be created. This time-dependent cloud will be a very complicated inhomogeneous formation including electromagnetic oscillations and waves of different type. Some of these waves will be observed on the Earth's surface. Rarefiel regions of the magnetoplasma behind, and dense regions in front of the shuttle orbiter (SO) and the subsatellite (SS) will arise. The neutral nitrogen beam ejected by the thruster becomes an ion beam on the day-light part of the orbit. Its energy is much greater than the local thermal energy. Instabilities of different kind as well as diffusion and recombination effects are expected to accompany the interaction of these beams with the surrounding plasma. The electron beams will produce other types of instabilities. By the electrons precessing along the magnetic-field lines, a current (5·103V, 0.5 A) should be induced in the 20th km length conducting tether. It will be closed at the bottom of the ionosphere. This huge magnetic loop, so-called «phantom loop» (PL), should accompany the tether system along its orbit. The length of this «tether electromagnetic tail» (TEMT) is about 200 km, its magnetic moment will be about 1013 A·cm2. Alfven waves and nonlinear effects of heating type may be produced by this loop along the magnetic-field lines. «Strings» of hot plasma may accompany the tether system.
Stereoselective synthesis of 2,4-bridged pyridinophanes☆

Abstract Reaction of the indole ether 3 with phenyl (trichloromethyl) mercury gives the syn -metacyclophane 5 , exclusive of the anti -enantiomer 6 . These ethers are new and their structures were established by their independent synthesis from the corresponding alcohols 7 and 8 . These data are consistent with the conclusion that the intermediate cyclopropane 4 is formed by stereosperific addition of dichlorocarbene trans to the ethoxy group. Additional results are described providing evidence for the resistance of the benzylic carbon atoms in these highly constrained metacyclophanes to undergo change of hybridization from sp 3 to sp 2 .
A Self-Assembled, Decameric Water Cluster Stabilized by a Cyano-Bridged Copper(II) Complex

A self-assembled, decameric water cluster stabilized by a cyano-bridged copper(II) complex was characterized by X-ray diffraction studies, FTIR, and thermogravimetric (TG) and differential scanning calorimetric (DSC) analyses. Every water cluster is connected strongly, via hydrogen bonds, to four cyano nitrogens of a [Fe(CN)6]4- anion. The complex water rings are stable indefinitely at room temperature, and when thermally decomposed, the water loss is irreversible.
Probing the molecular mechanisms of AZT drug resistance mediated by HIV-1 reverse transcriptase using a transient kinetic analysis

Several hypotheses have been proposed to explain the development of resistance to the anti-HIV drug AZT. Clinical findings show that AZT resistance mutations in HIV-1 reverse transcriptase (RT) not only reduce susceptibility to thymidine analogues but may also confer multi-dideoxynucleoside resistance. In this report, we describe transient kinetic studies establishing the biochemical effects of AZT resistance mutations in HIV-1 RT on the incorporation and removal of natural and unnatural deoxynucleotides. While the physiological role remains to be elucidated, the largest biochemical difference between wild-type and AZT resistant HIV-1 RT manifested itself during ATP-mediated deoxynucleotide removal. Enhanced removal resulted from an increase in the maximum rate of chain terminator excision, suggesting that mutated residues play a role in the optimal alignment of substrates for ATP-mediated removal. The efficiency of pyrophosphorolysis was not increased by the presence of AZT resistance mutations. However, a 2-fold decrease in the extent of inhibition caused by the next correct nucleotide during pyrophosphorolytic cleavage of a D4TMP chain-terminated primer may illustrate how this mutant can utilize pyrophosphate to enhance resistance. The inability of RT to catalyze removal of a chain terminator from an RNA-RNA primer-template may show how slight changes in selectivity against AZTMP incorporation during the initiation of DNA synthesis can contribute to high-level resistance. Taken together, these results suggest that multiple modes of resistance may be conferred by these mutations. Structure-activity studies of chain terminator removal suggest that analogues that form tight interactions with residues in the RT active site may be more prone to resistance mechanisms mediated by removal.