cssi/SciSciGPT-SciSciNet huggingface dataset:
Synaptonemal complex analysis of heteromorphic trivalents in Lemur hybrids

Synaptonemal complexes (SCs) in surface spread pachytene spermatocytes of Lemur resemble those in other mammals and are of two types: metacentric (or submetacentric) and acrocentric, with a very short second arm. In autosomal SC and mitotic karyotypes of Lemur fulvus (2n=60) a 1∶1 proportionality in relative length is observed as in other mammals. In an intraspecific lemur hybrid (2n=55) obtained by mating L. fulvus rufus (2n=60) x L. fulvus collaris (2n=51), G-band patterns show that 10 single acrocentric mitotic chromosomes correspond to the arms of 5 single metacentrics, implying homology. It is inferred that the metacentrics have evolved by centric (Robertsonian) fusion of the acrocentrics. In the SC karyotype of the hybrid all SCs are normal except for five which have the configurations expected of metacentric-acrocentric trivalents. Similarly, in L. f. collaris (2n= 51), with one unpaired metacentric and two unpaired acrocentrics, one such SC trivalent is present in the complement. In an SC trivalent, each of the acrocentric long axes is synapsed with an arm of the metacentric axis, confirming the homology predicted from banding similarities. At late zygotene, the acrocentric short arms, which are non-homologous, are the last to pair, demonstrating that synapsis of the homologous arms occurs first. At later pachytene the acrocentric short arms are fully synapsed, producing a short SC side arm. This subsequent non-homologous synapsis is taken to be an instance of the synaptic adjustment phenomenon which has been shown to lead to non-homologous synapsis in a duplication and several inversions in the mouse. The kinetochore of the metacentric is the same size as those of the acrocentrics, and thus is unlikely to have arisen by true centromeric fusion, but rather by a translocation. The kinetochores of the acrocentrics always lie together on the same side of the metacentric kinetochore (cis configuration), implying a single pairing face on the metacentric axis. The observed trivalent configuration may well constitute a prerequisite for proper meiotic disjunction in metacentric-acrocentric heterozygotes. Such a mechanism is consistent with fertility regularly observed in such hybrid lemurs.
Spatial Parameters and Shape Factors of the Normal Atrial Vectorcardiogram and Its Scalar Components

New quantitative norms for clinical evaluation of the atrial vectorcardiogram are presented. Real-time computer processing digitizes atrial electrocardiograms, reduces random noise content, rectifies base-line configuration, and corrects preamplifier distortion. Axial-system leads of 106 normal persons were so treated. The basic information derived includes spatial distribution and magnitudes of P, TP, and polar P vectors; length, width, and planarity of P loops; spatial P-TP angles; and the Eulerian angles of P-loop normalization. Normal P vectors show predominant leftward, inferior, and anterior orientation, with opposing TP direction. Polar P vectors show predominant superior, anterior, and leftward clustering. The scatter of parameters in the orthogonallead frontal plane is about the same as for the tetrahedral system. Similarly, the atrial deflections of normals show equally rich notching in both systems. Resolution of the P-wave population into uncorrelated components, followed by resynthesis from t...
Pre-spawning water temperature affects sperm respiration and reactivation parameters in male carps

Concentration, ability to motility, motility during the second activation (reactivation), and endogenous respiration were studied in sperm from two experimental groups of carp males. Group 1 was maintained for 7 days at 15°C (cold water (CW) group), whereas the second group was subjected to a temperature of 20°C (warm water (WW) group) before sperm sampling. Reactivation were achieved after incubation of firstly activated sperm in media with osmotic pressure adjusted up to 300 mOsm*kg−1 by increasing K+ concentration. Statistically significant reduction of spermatozoa concentration in CW samples versus WW (from 46.0 ± 12.5 (15°C) to 59.3 ± 7 109 (20°C) spermatozoa /ml) have been observed. The sperm of the CW group required a significantly longer incubation time (37 min) under isotonic conditions to achieve a maximum percentage of potent motility at repeated activation than the WW group (23 min). After activation of sperm motility, an increase of respiration rate up to maximum level has been found, this level remained the same under condition of recovering the potential to repeated activation. During the sperm movement respiration rate, in CW group (6.1 nmolO2/min/109spermatozoa) and WW (3.9 nmolO2/min/109spermatozoa), was significant higher compared to nonactivated sperm (2.4 nmolO2/min/109spermatozoa for CW and 1.1 nmolO2 /min/109spermatozoa for WW). And keeping males for 7 days at 15°C increase the respiration rate of sperm.
A Meier-Gorlin syndrome mutation in a conserved C-terminal helix of Orc6 impedes origin recognition complex formation

Cell division is essential for organisms to be able to grow, to repair tissues and to proliferate. However, cells can only divide once they have successfully replicated their DNA. Many different molecules are involved in these two processes, including a large multi-protein assembly called the origin recognition complex that helps to start the process of DNA replication. This complex contains six proteins but relatively little is known about its structure. It is also unclear how much origin recognition complexes (ORCs) differ between species. Now, Bleichert et al. have found a way to stabilize a specific conformation of Drosophila ORC, and have gone on to determine its structure at a higher resolution than was previously possible. This approach revealed that the arrangement of protein subunits in Drosophila ORC is similar to that found in yeast ORC. Most of the ORC subunits have similar amino acid sequences in both species. However, the Orc6 subunit was regarded a notable exception for a long time, with the yeast and Drosophila versions of this subunit having different sequences of amino acids. Bleichert et al. show that the Orc6 subunits actually have important similarities, both in sequence and in function. In particular, the C-terminus of the Orc6 protein contains similar amino acids in both yeast and Drosophila. Moreover, it performs the same role—binding to another subunit—in both yeast and Drosophila. As well as being important for cell division, human ORC has been implicated in Meier-Gorlin syndrome, a type of dwarfism. Mutations in three of the six ORC subunits, including Orc6, have been found in people with Meier-Gorlin syndrome. The mutations in Orc6 that are associated with this syndrome are in the C-terminus, which suggests that some symptoms of the syndrome may be caused by DNA replication not being initiated correctly. Consistent with this idea, Bleichert et al. show that the introduction of the Meier-Gorlin syndrome mutation into Orc6 prevents this subunit from binding to the rest of ORC, and similar mutations do not support DNA replication in in vivo experiments. These results should increase our understanding of the function of Orc6 and its role in Meier-Gorlin syndrome, and also provide new insights into the changes in ORC architecture that have occurred during evolution.
Surface sediment analysis of a rock glacier

Three trend surface techniques are used to evaluate the nature and distribution of the surface sediments of a rock glacier. Trend surface analysis, vector trend analysis, and most predictable surface (MPS)mapping suggest that long-term rock glacier creep causes the highly variable debris cover to display crude sorting and orientation patterns. Poorly sorted and randomly oriented surface materials may be the result of insufficient time for slowly evolving rock glacier sediment distributions to be established and/or the site of glacial erosion or deposition.
Land management: Forests, fires and climate

A new analysis of the effect of climatic variation on forest fires goes back several thousand years. One take-home message is that a one-size-fits-all forest management strategy is, literally, short-sighted.
Transgenic and gene targeting studies of hair cell function in mouse inner ear.

Despite the rapid discovery of a large number of genes in sensory hair cells of the inner ear, the functional roles of these genes in hair cells remain largely undetermined. Recent advances in transgenic and gene targeting technologies in mice have offered unprecedented opportunities to genetically manipulate the expression of these genes and to study their functional roles in hair cells in vivo. Transgenic analyses have revealed the presence of hair-cell-specific promoters in the genes encoding Math1, myosin VIIa, Pou4f3, and the alpha9 subunit of the acetylcholine receptor (alpha9 AChR). Targeted inactivation using embryonic stem cell technology and transgenic expression studies have revealed the roles of several genes involved in hair cell lineage (Math1), differentiation (Pou4f3), mechanotransduction (Myo1c, and Myo7a), electromotility (Prestin), and efferent modulation (Chrna9, encoding alpha9 AChR). Although many of these genes also play roles in other tissues, inactivation of these genes in hair cells alone will soon be possible by using the Cre-loxP system. Also imminent is the development of genetic methods to inactivate genes specifically in mouse hair cells at a desired time, by using inducible systems established in other types of neurons. Combining these types of manipulation of gene expression will enable hearing researchers to elucidate some of the fundamental and unique features of hair cell function such as mechanotransduction, frequency tuning, active mechanical amplification, and efferent modulation.
ENDOR Study of Biradicals Randomly Oriented in a Rigid Matrix

An ENDOR study has been made of the structure of ketyl dimers with triplet ground state randomly oriented in a rigid matrix. The measurements give signs and magnitudes of hyperfine coupling constants and also give information on 23Na quadrupole couplings. The ENDOR results can be accounted for using the structural model previously proposed for these dimers.
The diffusion of metal in polymer films

Abstract Both the Rutherford backscattering spectrometry (RBS) and the secondary ion mass spectrometry (SIMS) techniques have been employed in studying the diffusion of metal atoms in a polymer film. Au,Ag and Cu films of uniform 90–110 A thickness were evaporated on polymethyl methacrylates (PMMA) and lucite. Radiation damage on lucite was limited by scanning a 1.25 MeV He ion beam in a large circular pattern on a lucite disk. The Au diffusion tail was clearly visible in the RBS spectrum. The solubility of Au in lucite has been estimated at 90°C annealing for 48 h. The SIMS profile of 100 A Au film on the high molecular weight PMMA is consistent with the RBS result for lucite.
A new fluorometric method for the determination of pyridoxal 5'-phosphate.

Abstract A new fluorometric method using semicarbazide for the determination of pyridoxal and pyridoxal 5′-phosphate (PLP) in whole blood, red cells and plasma has been developed. Semicarbazide breaks the Schiff base of PLP and proteins by “trans-Schiffization” reaction and forms semicarbazone of PLP. The semicarbazone of PLP emits strongly at 460 nm when excited at 380 nm. Several metabolic intermediates were tested for the possible interference. Only pyridoxal was found to interfere. The interference can be corrected since pyridoxal emits at 380 nm when excited at 320 nm. Using this method we found that rabbit red cells in vivo are freely permeable to PLP.
Comparison of burning characteristics of live and dead chaparral fuels

Wildfire spread in living vegetation, such as chaparral in southern California, often causes significant damage to infrastructure and ecosystems. The effects of physical characteristics of fuels and fuel beds on live fuel burning and whether live fuels differ fundamentally from dead woody fuels in their burning characteristics are not well understood. Toward this end, three common chaparral fuels prevalent in southern California, chamise, manzanita, and ceanothus, were investigated by burning them in a cylindrical container. The observed fire behavior included mass loss rate, flame height, and temperature structure above the burning fuel bed. By using successive images of the temperature field, a recently developed thermal particle image velocity (TPIV) algorithm was applied to estimate flow velocities in the vicinity of the flame. A linear regression fit was used to explain the observed time difference between when maximum flame height and maximum mass loss rate occur, as a function of fuel moisture content. Two different methods were used to extract power laws for flame heights of live and dead fuels. It was observed that the parameters defined in the well-known two-fifths power law for flame height as a function of heat release rate were inadequate for live fuels. As the moisture content increases, the heat release rate in the power law needs to be calculated at the time when the maximum flame height is achieved, as opposed to the maximum mass loss rate. Dimensionless parameters were used to express local temperature and velocity structure of live and dead chaparral fuels in the form of a Gaussian profile over different regimes in a fire plume.
A Forward Explicit Algorithm With Automatic Error Control for a Cyclic Thermoviscoplastic Coupled With Damage Model of Sn-Pb Solder

A self-correcting forwards gradient time integration procedure is formulated for the integration of a unified viscoplastic constitutive coupled with damage model for a eutectic solder alloy under cyclic fatigue loading. The procedure has been implemented numerically in the commercial finite element (FE) code ABAQUS (Version 6.2) via the user-defined material subroutine. The stress (constitutive) Jacobian explicit solution is derived. Schemes of the algorithm are verified by a series of numerical examples, including (1) Single-element simulations for uniaxial test, tensile creep, and fatigue simulations to reveal the optimum combination of the user-specified tolerance and the prescribed load step size to obtain a desired accuracy at a minimum cost. (2) Two three-dimensional analyses for monotonic tensile loading and fatigue loading were conducted for a miniature specimen of solder to show the capability of the proposed procedure to deal with thermomechanical loading. (3) Simulation of a shear notched specimen under monotonic loading was compared with the test to illustrate the ability of this algorithm for the specimen that has a serious damage region. The numerical examples illustrated that the explicit algorithm as well as empirical rule for adaptive time increment is effective for simulating cyclic thermoviscoplastic behavior of solder. The research can be applied to the simulation of viscoplasic behavior and fatigue life of softening materials.Copyright © 2005 by ASME
Noncovalent polymerization of mesogens crystallizes lysozyme: correlation between nonamphiphilic lyotropic liquid crystal phase and protein crystal formation.

Crystallization of proteins is important for fundamental studies and biopharmaceutical development but remains largely an empirical science. Here, we report the use of organic salts that can form a class of unusual nonamphiphilic lyotropic liquid crystals to crystallize the protein lysozyme. Certain nonamphiphilic organic molecules with fused aromatic rings and two charges can assemble into stable thread-like noncovalent polymers that may further form liquid crystal phases in water, traditionally termed chromonic liquid crystals. Using five of these mesogenic molecules as additives to induce protein crystallization, we discover that molecules that can form liquid crystal phases in water are highly effective at inducing the crystal formation of lysozyme, even at concentrations significantly lower than that required for forming liquid crystal phases. This result reveals an example of inducing protein crystallization by the molecular assembly of the additives, and is consistent with a new mechanism by which ...
Serum plays a critical role in modulating [Ca2+]c of primary culture bone cells exposed to weak ion‐resonance magnetic fields

Primary-culture bone cells were exposed to ion-resonance (IR) magnetic fields tuned to Ca{sup 2+}. Cytosolic calcium concentration, [Ca{sup 2+}]{sub c}, was measured by using fura-2 during field exposure. The fields investigated were 20 {micro}T static + 40 {micro}T p-p at either 15.3 or 76.6 Hz, and 0.13 mT static + either 0.5 or 1.0 mT p-p at 100 Hz. Other parameters included field orientation, culture age, and the presence of serum during exposure. Total experiment time was 29.5 min. The field was applied after 2 min, and bradykinin was added as an agonist control after 22 min. The data were quantified on a single-cell basis during the 2--22 min exposure period in terms of the magnitude of the largest occurring [Ca{sup 2+}]{sub c} spike normalized to local baseline. Field-exposed and control groups were characterized in terms of the percent of cells exhibiting spike magnitudes above thresholds of 100 or 66% over baseline and were compared by using Fisher`s exact test. Without serum, there was little evidence that IR magnetic fields altered [Ca{sup 2+}]{sub c}. However, in the presence of 2% serum, 3 of the 16 experiments exhibited significant effects at the 100% threshold. Reducing this threshold to 66% resulted inmore » five experiments exhibiting significant effects. Most strikingly, in all of these cases, the field acted to enhance [Ca{sup 2+}]{sub c} activity as opposed to suppressing [Ca{sup 2+}]{sub c} activity. These findings suggest a role for serum or for constituents within serum in mediating the effects of IR magnetic fields on cells and may provide a resolution pathway to the dilemma imposed by theoretical arguments regarding the possibility of such phenomena. Possible roles of serum and future studies are discussed.« less
New telechelic polymers and sequential copolymers by polyfunctional initiator–transfer agents (inifers). XLI. Kinetic and reactivity studies on sterically hindered inifers

The kinetics of chain transfer to the bifunctional initiating and transfer agents (binifers) 1,4-di(2-chloro-2-propyl)benzene (p-DCC), 1,3-di(2-chloro-2-propyl)-5-tert-butylbenzene (m-tBuDCC), and 1,3-di(2-chloro-2-propyl)-4,6-dimethylbenzene (m-DMeDCC) in the polymerization of isobutylene has been investigated. Chain transfer to monomer was shown to be absent up to −20°C in CH3Cl/n-hexane and CH2Cl2/n-hexane mixtures using the m-tBuDCC/BCl3 binifer system. Chain transfer constants (Ci) to m-tBuDCC and kt/kp ratios determined in the range from −30°C to −80°C in CH3Cl/n-hexane mixtures and pure CH3Cl solvent are reported, and the activation energy differences Etr,l − Ep and Et − Ep were calculated. Chain transfer constants to p-DCC and m-DMeDCC were determined by the use of pure CH3Cl diluent at −50°C. The chain transfer reactivity of five different inifers is discussed and compared based on CI values obtained under identical conditions, with special regard to the new, sterically hindered binifer m-DMeDCC of extraordinary reactivity.
Shakedown Analysis of Geogrid-Reinforced Granular Base Material

AbstractThis research study was performed to examine the shakedown behavior of geogrid-reinforced unbound granular materials and evaluate the factors that affect the shakedown stress limits. To achieve this objective, the study was performed through conducting repeated load triaxial (RLT) tests on both unreinforced and geogrid-reinforced unbound granular specimens. A multistage RLT test, in which only one sample is needed to determine the shakedown stress limits, was selected in preference to a single-stage RLT test, in which several tests on multiple samples are required. Five geogrids of different tensile modulus and different aperture geometries (three rectangular or biaxial and two triangular or triaxial) were used. The test results clearly demonstrated the potential benefits of placing the geogrid within the unbound granular base specimen in terms of permanent deformation reduction. The benefits of the geogrid are more prevalent at higher stress levels and for higher tensile modulus geogrids. The inc...
A comprehensive guide to antibody and T‐cell responses in type 1 diabetes

Type 1 diabetes (T1D) is an organ-specific autoimmune disease in which the insulin-producing beta cells in the pancreatic islets are selectively eliminated. T cells specific for beta-cell antigens are the mediators of this precise cellular destruction. However, antibodies to beta-cell proteins are also generated and may be used for predicting disease in at-risk populations. Over the past two decades, numerous beta-cell proteins and lipids have been implicated as autoantigens in patients or in non-obese diabetic (NOD) mice, a well-studied animal model of T1D. Here, we present a review of these antigens, accompanied by their T-cell epitopes, where known, and a discussion of our current understanding of why particular self-proteins become disease-inciting antigens. Although two dozen beta-cell antigens have been identified to date, few of these have been confirmed to be recognized by pathogenic T cells early in the disease process. Further identification and characterization of initiating beta-cell antigens targeted by pathogenic T cells should be a priority for future studies.
Serial Transmission in Rhesus Monkeys of an Agent Related to Hepatitis-associated Antigen

An agent that stimulated antibody to hepatitis-associated antigen (HAA) was transmitted to rhesus monkeys and serially passed in this species. In contrast to the results obtained with rhesus monkeys, vervets appeared to be refractory to infection with the agent. Antibody responses in infected rhesus monkeys were similar in magnitude and pattern to seroconversions observed in humans naturally or artificially infected with the virus of hepatitis B. However, in contrast to human infection, infection of the rhesus was inapparent and not associated with elevated levels of transaminase or obvious pathology of the liver.
Deformation enhanced decarburization of WC-Co

The paper describes an unusual transformation that takes place only within the deformed region of identations. Under a suitable ambient temperature decarburization of cemented WC-Co on annealing is enhanced by prior localized deformation. Within individual WC grains, plate-like growth of a mixed carbide (either Co/sub 3/W/sub 3/C or Co/sub 6/W/sub 6/C) occurs preferentially. On some occasions intrusion of the substoichiometric carbide is preceded by a structural transformation in the WC slip band. This transformation is consistent with the formation of an orthorhombic (pseudo-hexagonal) WC phase that may be derived from the original structure by the passage of one partial dislocation on every sucessive slip plane.
Developmental Changes in Medial Auditory Thalamic Contributions to Associative Motor Learning

Eyeblink conditioning (EBC) was used in the current study to examine the mechanisms underlying the ontogeny of associative motor learning in rats. Eyeblink conditioning emerges ontogenetically between postnatal day 17 (P17) and P24 in rats. Previous studies used electrical stimulation to show that the ontogeny of EBC is influenced by developmental changes in input from the medial auditory thalamus to the pontine nuclei, which in turn affects input to the cerebellum. The current study used tetrode recordings to examine the ontogeny of medial auditory thalamic sensory responses to the conditioned stimulus (CS) and learning-related activity during EBC. Rat pups were implanted with multiple tetrodes in the medial nucleus of the medial geniculate (MGm) and suprageniculate (SG) and trained on delay EBC on P17-P19, P24-P26, or P31-P33 while recording spike activity. Developmental changes in MGm and SG sensory-related activity were found during a pretraining session with unpaired presentations of the auditory CS and periorbital stimulation unconditioned stimulus (US). Substantial developmental changes were observed in learning-related activity in the MGm and SG during CS-US paired training. The ontogenetic changes in learning-related activity may be related to developmental changes in input to the medial auditory thalamus from the amygdala and cerebellum. The findings suggest that the ontogeny of associative motor learning involves developmental changes in sensory input to the thalamus, amygdala input to the thalamus, thalamic input to the pontine nuclei, and cerebellar feedback to the thalamus.
The VSV polymerase can initiate at mRNA start sites located either up or downstream of a transcription termination signal but size of the intervening intergenic region affects efficiency of initiation.

Abstract Transcription by the vesicular stomatitis virus (VSV) polymerase has been characterized as obligatorily sequential with transcription of each downstream gene dependant on termination of the gene immediately upstream. In studies described here we investigated the ability of the VSV RNA-dependant RNA polymerase (RdRp) to access mRNA initiation sites located at increasing distances either downstream or upstream of a transcription termination signal. Bi-cistronic subgenomic replicons were constructed containing progressively extended intergenic regions preceding the initiation site of a downstream gene. The ability of the RdRp to access the downstream sites was progressively reduced as the length of the intergenic region increased. Alternatively, bi-cistronic replicons were constructed containing an mRNA start signal located at increasing distances upstream of a termination site. Analysis of transcription of these “overlapped” genes showed that for an upstream mRNA start site to be recognized it had to contain not only the canonical 3′-UUGUCnnUAG-5′ gene start signal, but that signal needed also to be preceded by a U7 tract. Access of these upstream mRNA initiation sites by the VSV RdRp was proportionately reduced with increasing distance between the termination site and the overlapped initiation signal. Possible mechanisms for how the RdRp accesses these upstream start sites are discussed.
High‐performance liquid chromatography/tandem mass spectrometry: Its use for the identification of stanozolol and its major metabolites in human and equine urine

A screening procedure for the anabolic steroid stanozolol in human and equine urine was developed based on enzymatic hydrolysis, liquid-liquid extraction and reversed-phase liquid chromatography combined on-line with tandem mass spectrometry. The column effluent was introduced into the atmospheric pressure ionization source of a triple-quadrupole mass spectrometer via a heated pneumatic nebulizer liquid chromatograph/mass spectrometer interface. Abundant protonated molecular ions were generated by corona discharge ionization. Confirmation of stanozolol and several of its hydroxylated and dihydroxylated metabolites isolated from both human and equine urine was accomplished by collision-induced dissociation of their parent ions. Interpretation of the daughter ion mass spectra gave valuable information for the structural elucidation of the detected metabolites. Using the selected reaction monitoring detection mode the presence of the urinary excretion products could be monitored in equine urine up to one day and in human urine for several days after oral administration of stanozolol. Microbore high-performance liquid chromatography/ion spray mass spectrometry of an ion-pair extract enabled the direct detection of intact sulfoconjugated hydroxy-metabolites in human urine.
Interaction of spider mites (Acari: Tetranychidae) and water stress on gas-exchange rates and water potential of almond leaves.

Preparation of almond orchards for harvest by withdrawal of irrigation may result in prolonged periods of water stress. It is during these periods (from July to mid-August) that mite populations often increase and are associated with partial defoliation. The impact of spider mites and water stress, alone and in combination, was investigated on gas exchange and water potential of almond leaves during the 1982 and 1983 growing seasons. The impact of water stress on mite densities was also studied in 1982. In both years, water stress caused highly significant reductions in leaf water potential, whereas mites alone had no measurable impact. In 1982, significantly higher mite eggs and motile stages developed on water-stressed foliage as compared with unstressed foliage. The effect of mites on gas exchange of water-stressed leaves was greater than on unstressed leaves in 1982 as indicated by significant interactions. Significant interactions representing the same trend did not occur in the 1983 trial. When water stress was severe, as in 1983, no additional impact of mites on gas exchange was detected.
Seismic signature analysis for discrimination of people from animals

Cadence analysis has been the main focus for discriminating between the seismic signatures of people and animals. However, cadence analysis fails when multiple targets are generating the signatures. We analyze the mechanism of human walking and the signature generated by a human walker, and compare it with the signature generated by a quadruped. We develop Fourier-based analysis to differentiate the human signatures from the animal signatures. We extract a set of basis vectors to represent the human and animal signatures using non-negative matrix factorization, and use them to separate and classify both the targets. Grazing animals such as deer, cows, etc., often produce sporadic signals as they move around from patch to patch of grass and one must characterize them so as to differentiate their signatures from signatures generated by a horse steadily walking along a path. These differences in the signatures are used in developing a robust algorithm to distinguish the signatures of animals from humans. The algorithm is tested on real data collected in a remote area.
The Prevalence and Significance of Cannabis Use in Patients Prescribed Chronic Opioid Therapy: A Review of the Extant Literature

Background. Cannabis is the most widely consumed illicit drug in the United States. Its use, particularly in early initiates, is associated with subsequent development of other drug and alcohol use disorders. Objective. The authors examined the prevalence of cannabis use and the association between cannabis use and aberrant opioid-related behaviors in patients prescribed chronic opioid therapy for persistent pain. Methods. PubMed was queried for studies of chronic opioid therapy in which aberrant opioid-related behaviors were quantitatively examined and in which cannabis use data (as determined by cannabinoid-positive urine drug tests) were extricable from that of other substances of abuse. Results. The prevalence of cannabis use among patients prescribed chronic opioid therapy in these studies ranged from 6.2% to 39%, compared with 5.8% in the general United States population. Furthermore, cannabis use in chronic opioid patients shows statistically significant associations with present and future aberrant opioid-related behaviors. Conclusion. Cannabis use is prevalent in patients prescribed chronic opioid therapy and is associated with opioid misuse. Further research is necessary to clarify the strength and the nature of the association between cannabis use and opioid misuse, and to address additional questions about the consequences of cannabis use in the context of chronic opioid therapy.
Generators, relations and symmetries in pairs of 3×3 unimodular matrices

Abstract Denote the free group on two letters by F 2 and the SL ( 3 , C ) -representation variety of F 2 by R = Hom ( F 2 , SL ( 3 , C ) ) . There is a SL ( 3 , C ) -action on the coordinate ring of R , and the geometric points of the subring of invariants is an affine variety X . We determine explicit minimal generators and defining relations for the subring of invariants and show X is a degree 6 hyper-surface in C 9 mapping onto C 8 . Our choice of generators exhibit Out ( F 2 ) symmetries which allow for a succinct expression of the defining relations.
Race-Based Differential Prediction in Air Force Technical Training Programs.

Bayesian Johnson-Neyman methodology was used to investigate differential prediction by race in United States Air Force technical training programs. Meaningful Johnson-Neyman regions of differences were found in eight of nine comparisons. In all nine training courses the regressions for blacks were flatter than for whites and the race-differentiated regression lines intersected within the range of predictor test scores. In six cases the cut-score for course qualification was within the Johnson-Neyman region, and in every case the bias was negative for blacks. It is noted that if the cut score had been set substantially higher the bias would have been positive for blacks in all cases. This analysis may explain why earlier studies that averaged bias across the predictor distribution yielded mixed results. It is hypothesized that the consistent results obtained here are a consequence of the lower predictability found in the black subpopulation.
Confer at the ISTA congress

Computing and telecommunications were used during the Second International Congress of the International Society for Technology Assessment (ISTA) to facilitate the discussion and contribute to the Congress report. In particular, the telecommunications activity was designed to enhance interaction on substantive issues and convergence on conclusions and interpretations. Only incidentally were we conducting an experiment or trial (with support from NSF) for a community of potential users of computer-aided conferencing.
Susceptibility of pines to attack by the Nantucket pine tip moth in southern California.

Forty species of pine, Pinus spp., were tested for susceptibility to attack by Rhyacionia Frustrana (Comstock) at a planting in San Diego Co., Ca. Those pine species known to be susceptible to moth attacks in the southeastern U.S. and planted in San Diego Co. showed the same pattern of susceptibility with 2 exceptions: P. caribea Morelet reported as a host of the moth remained unattacked and P. glabra Walt was attacked in San Diego Co. but is not reported as a host. A higher proportion of the hard pine species ( Pinus ) was attacked than were the soft pine species Strobus ). Although 4 native California species were susceptible, Monterey pine, P. radiate D. Don, bishop pine, P. muricata D. Don, lodgepole pine, P. Contorta Dougl., and digger pine, P. sabiniana Dougl., the moth is not thought to pose a serious threat to these species in their native stands.
Hydraulic networks in nature

The analysis of natural hydraulic networks over a wide range of scales, allowed by modern digital mapping technology, reveals extraordinary diversity of natural forms, and yet deep regularity and symmetry, regardless of geology, climate, vegetation or exposed lithology. River networks are indeed a paradigm of scale-invariant, or fractal, forms ubiquitous in nature, whereas tidal networks bear the both the signatures of scaling processes and of different dynamic origin and susceptibility to environmental factors. Here I review a subjective choice of linked results, suggesting that the dynamic origin of the recurrence of similar network forms in nature relates to a common mechanism of growth and stabilization of open, dissipative systems with many degrees of freedom.
William Rowan Hamilton, Michael Faraday, and the Revival of Boscovichean Atomism

Although the contributions of Sir William Rowan Hamilton to mathematical physics are well known, the physical framework for some of his major endeavors has long been neglected. A philosophical idealist, Hamilton preferred to base his conception of physical reality upon “force” or “power” rather than “matter.” Hamilton was thus drawn to the atomism of Roger Boscovich who replaced hard atoms with point centers of force. Hamilton saw his mathematical contributions as the completion of the Boscovichean model, just as Lagrange, in some sense, completed the work of Newton. Hamilton agreed in his view of matter with Michael Faraday who likewise was drawn to Boscovichean atomism but who saw it mainly in the light of his electrical and chemical researches. Joseph Henry criticized Boscovichean atomism but really was criticizing Faraday's presentation, which omitted the concept of inertia.
New elites and their influence on entrepreneurial activity in Russia

Abstract When Russia transitioned to a democratic institutional system in 1991, some of its regions remained under control of old Communist Party elites, while some fell into the hands of political newcomers (“new elites”). Using a new panel dataset spanning 71 of the Russian regions over the years 1994–2006, I show that regions with new-elite governors whose rise to power was influenced by Putin ended up with significantly fewer small and medium enterprises (SMEs) than otherwise similar regions governed by old elites. One interpretation of this result is that Putin, in alliance with the oligarchs, sought to extend his power to the distant resource-abundant regions by promoting relatively inexperienced new elites to govern those regions. As the oligarchs of big business were allowed to monopolize the resources of the new-elite regions, entrepreneurial activity remained at depressed levels. The newcomers’ lack of leadership experience may have also contributed to this result.
Isolation of N-acetylethylenediamine from urine of patients on amesec

Abstract A composite part of aminophylline, 1,2-diaminoethane, is metabolized in man and rat to N-(2-aminoethyl)acetamide. The structure was assigned by degradation studies and confirmed by synthesis.
A Leadership Profile of Disadvantaged Youth Based on Leadership Strengths Indicator

The Leadership Strengths Indicator was administered to 42 boys and 47 girls, ranging in age from 10 to 15 years, who were identified as disadvantaged by their qualifications for the free or reduced lunch fee. The students' scores fell within the normal range of scores. A significant difference was found on Cluster scale III, High Level Participator in Group Activities, favoring the boys. Slight nonsignificant differences were found between the scores on Clusters I, Enjoys Group Activities, IV, Journalistic, and VI, Courageous.
Neuropathy and mortality in diabetes: Influence of pancreas transplantation

We collected information on patient status and cause of death for 545 insulin-dependent diabetic subjects who had cardiorespiratory reflex and nerve conduction tests performed to determine if presence and severity of autonomic and somatic neuropathy is associated with mortality and if a functioning pancreas transplantation (PTx) influences mortality. Follow-up was 12-138 months. Abnormal cardiorespiratory reflexes were present in 417 patients and there was abnormal nerve conduction in 392 patients. Mortality rates for patients with abnormal tests were higher (P < 0.0001) than for patients with normal tests. A total neuropathy score that included cardiorespiratory and nerve conduction test scores predicted survival better than separate scores. Patients with moderate neuropathy, but not those with severe neuropathy, who retained a functioning PTx, had longer survival times than patients whose PTx failed in the first 3 months. Considering only patients transplanted after 1985, those with moderate neuropathy who retained a functioning PTx had even longer survival times than nontransplanted patients.
The Media Downing of Pierre Salinger: Journalistic Mistrust of the Internet as a News Source

Through analysis of historical listserv dialogue and traditional media dissection of a watershed debate—that a missile caused the TWA 800 crash on July 17, 1996—this study seeks to shed light on an early example of journalistic wariness and mistrust of the Internet as a news source. Specifically, we analyze the rhetoric of the late Pierre Salinger's connections to the historic incident, and the credibility of the Internet as a news source, as debated by professional journalists on the Internet and in mainstream media forums. A rhetorical analysis of how this debate was framed suggests that negative journalistic perceptions of the Internet's news credibility were already solidifying by the mid-1990s, and have continued to do so since that time.
Learned aversions in rats fed a tryptophan-free diet.

Abstract Rats maintained for ten days on a tryptophan-free diet (TRP-FREE) consumed significantly less food than rats receiving the same diet supplemented with L-tryptophan (TRP-SUPP). On Day 11, both groups of rats were given a 24-hour two-diet preference test which allowed them to choose between the pre-exposed diet and a novel alternative. TRP-FREE rats displayed significantly lower preferences than TRP-SUPP rats for the pre-exposed diet. Reduced preferences were still present after animals had been allowed a week of free access to nutritionally adequate chow. The results suggest that the declines in food intake induced by a tryptophan-free diet may be based on learned aversions.
Exploring the Gender Differences in Protective Factors: Implications for Understanding Resiliency

Understanding the causes of why individuals desist from or are resilient to delinquency and drug use has become a salient social concern. Much research has centered on the effects that protective factors possess in fostering resiliency but that research has not fully explored how the effects of protective factors might vary across gender. Using a sample of 711 individuals from the National Longitudinal Survey of Youth, Child-Mother data set, the authors investigate how individual protective factors vary across gender on two measures of resiliency that document the lack of involvement in serious delinquency and drug use. They also examine whether the accumulation of protective factors varies across gender in fostering resiliency. The findings suggest that although males and females rely on different individual protective factors to foster resiliency, the accumulation of protective factors appears to be equally important for males and females in promoting resiliency. The authors discuss theoretical and policy implications.
Comparison of reactive oxygen scavenging systems between a cetacean (DKN1) and a porcine renal epithelial cell line (LLC-PK1).

Abstract A transformed renal epithelial cell line, (DKN 1 ), from an Atlantic Bottlenose Dolphin, Tursiops truncatus was established in this laboratory and has been used for in vitro genomic analysis and initial toxicological evaluations of dolphin cells. Studies were initiated to compare maintenance of normal antioxidant mechanisms in DKN 1 with similar mechanisms in cells of a pig kidney line, LLC-PK 1 . Levels of catalase, glutathione peroxidase, and of reduced glutathione in these dolphin cells were significantly lower than in the porcine cells. Both cell lines were then challenged with hydrogen peroxide at 0.01, 0.1, and 1.0 mM concentrations. The dolphin cells exhibited increased cytotoxicity with a concurrent increase in apoptosis at lower concentrations (0.1 mM) than those required to initiate cytotoxicity in the porcine cells (1.0 mM). Taken together, these results would indicate that the dolphin cells are more susceptible to the damaging effects of certain reactive oxygen species than their terrestrial counterparts.
Multi-Criteria Optimal Structural Design Under Uncertainty

A general framework for multi-criteria optimal design is presented which is well suited for performance-based design of structural systems operating in an uncertain dynamic environment. A decision theoretic approach is used which is based on aggregation of preference functions for the multiple, possibly conflicting, design criteria. This allows the designer to trade off these criteria in a controlled manner during the optimization. Reliability-based design criteria are used to maintain user-specified levels of structural safety by properly taking into account the uncertainties in the modeling and seismic loads that a structure may experience during its lifetime. Code-based requirements are also easily incorporated into this optimal design process. The methodology is demonstrated with a simple example involving the design of a three-story steel-frame building for which the ground motion uncertainty is characterized by a probabilistic response spectrum which is developed from available attenuation formulas and seismic hazard models.
Calcium intake in youth: sex, age, and racial differences in NHANES II.

Methods. Data from the NHANES II survey were used to determine whether the calcium intake of children ages 3–18 met the minimum recommended daily allowance. In addition, the impact of age, race, sex, and socioeconomic status on calcium intake and the density of calcium intake was explored. Results. The results indicated significant differences between groups of children based on age, sex, and race (P < 0.05). Males across all age groups (3–5, 6–7, 8–10, 11–12, 13–18) had a higher calcium intake than females. In addition, calcium intake levels among males always met or exceeded the minimum RDA. Levels among all blacks started below the minimum RDA in the age group 3–5. During the adolescent years, calcium intake again fell below the RDA for black males and for females of both races, with the calcium intake of the adolescent females resembling that of the group ages 3–5. In a multiple regression model sex, age, race, and total energy intake predicted 49% (P < 0.0001) of the variance in calcium intake. Socioeconomic status (using parents' reported income) was not a significant predictor. Another regression model was used to examine the relationship among age, race, sex, and socioeconomic status and its effect on the density of calcium intake (mg/kcal). While the overall model was significant (P < 0.0001) it accounted for only 3.5% of the variance. Conclusion. Age, sex, and race of the child significantly predicted the density of calcium (P 0.81), indicating that income level does not contribute to explaining these differences.
DESIGN OF A SPATIAL LINKAGE HAPTIC INTERFACE

This paper describes the mechanical and electrical design of a compact high fidelity desktop haptic interface that provides three-degree-of-freedom point-force interaction through a handheld pen-like stylus. The complete haptic device combines a spatial linkage, actuation, power amplification, and control electronics in a standalone package with a footprint similar to that of a notebook computer (33cm × 25cm × 10cm). The procedure used to design the statically balanced spatial linkage is explained and both an inexpensive lightweight plastic version and a high stiffness, high strength, aluminum and stainless steel version are presented. The theory and implementation of sinusoidal encoder interpolation and sinusoidal servo-motor commutation used to achieve high-fidelity haptic simulation is covered for two versions of electronic control hardware: custom hardware based on a digital signal processor (DSP) and an off-the-shelf design based on an embedded PC.Copyright © 2004 by ASME
The relationships among labor-force participation, service-sector employment, and underemployment.

In this study it is argued [that] underemployment is both affected by and affects the labor-force participation rate (LFPR) and the level of service employment. Interestingly the analysis reveals that service employment lowers the LFPR and raises underemployment. In turn underemployment increases the LFPR as more secondary workers are pushed into the labor market in an effort to support their households. Thus secondary workers are not pulled into the labor market by the availability of service jobs but are rather pushed into these jobs by the condition of underemployment that is brought on by the growing concentration of low-paying service jobs....A three-equation simultaneous equation model is developed to test our hypotheses [and] three-stage least squares...estimates of this model for the 100 largest [U.S.] metropolitan areas are presented.... (EXCERPT)