cssi/SciSciGPT-SciSciNet huggingface dataset:
The roles of child maltreatment types and peer relationships on behavior problems in early adolescence.

Abstract Background Although previous research has established that child maltreatment (CM) and peer relationships (i.e., deviant peer affiliation, being ignored by peers) are strong predictors of adolescent internalizing (INT) and externalizing (EXT) behavior problems, no study has examined the above effects concurrently. Nor have researchers investigated the potential peer relationship differences in the effects of CM types on adolescent behavior problems. Thus, this study aims to examine the independent and combined effects of different types of CM and peer relationships on behavior problems. Methods The Generalized Estimating Equations approach was conducted using the Longitudinal Studies of Child Abuse and Neglect. Child-Protective-Services reports and youth self-reports were used for each type of CM. Deviant peer affiliation (DP) has been assessed using a modified version of the Youth-Risk-Behavior-and-Monitoring-the-Future Survey, while being ignored by peers was assessed using a single question. Adolescent INT and EXT were measured using the Youth-Self-Report. Results Emotional abuse was associated with both INT and EXT, whereas physical abuse was associated with EXT. Higher DP and higher incidence of being ignored by peers were both associated with higher levels of INT and EXT. Emotionally abused youth with higher levels of DP had less INT, compared to emotionally abused youth with lower levels of DP. Conclusion The Findings indicate the need for interventions that 1) take into account the different effects of CM types, specifically for emotionally abused youth; 2) help youth to build positive relationships with peers; and 3) work to reduce the possibility of affiliation with deviant peers.
Passerine birds as hosts for Ixodes ticks infected with Borrelia burgdorferi sensu stricto in southeastern Virginia

The ecology of vector-borne diseases in a region can be attributed to vector-host interactions. In the United States, tick-borne pathogens are the cause of the highest number of reported vector-borne diseases. In the mid-Atlantic region of the eastern United States, tick-borne diseases such as Lyme disease, have increased in incidence, with tick-host-pathogen interactions considered a contributing factor to this increase. Ticks become infected with pathogens after taking a blood meal from a systemically infected host or through a localized infection while co-feeding on a host with other infected ticks. The host not only plays a role in pathogen acquisition by the tick, but can also facilitate dispersal of the tick locally within a region or over greater distances into new geographical ranges outside of their historical distributional range. In this study conducted in southeastern Virginia (USA), we examined the interaction between both resident and migratory bird species and Ixodes ticks, the primary vectors of Borrelia burgdorferi sensu stricto (s.s.) the main causative agent of Lyme disease on the East coast of the United States. Over a two-year period (2012-2014), 1879 passerine birds were surveyed, with 255 Ixodes ticks tested for the presence of Borrelia spp. Eighty passerine birds (4.3 %) representing 17 bird species were parasitized by at least one Ixodes tick, but only three bird species were parasitized by Ixodes ticks that tested positive for B. burgdorferi s.s. Twenty Ixodes ticks (7.8 %) tested positive for B. burgdorferi s.s. with nearly all collected from resident bird species including the Carolina wren (Thryothorus ludovicianus) and brown thrasher (Toxostoma rufum). Given that millions of birds pass through southeastern Virginia during migration, even with the low number of Ixodes ticks parasitizing passerine birds and the low prevalence of B. burgdorferi s.s. found within Ixodes ticks collected, the sheer volume of passerine birds suggests they may play a role in the maintenance and dispersal of B. burgdorferi s.s. in southeastern Virginia.
Whole blood transcriptome analysis using RNA sequencing in individuals with insomnia disorder and good sleepers: a pilot study.

Background: Insomnia is a highly prevalent condition that is associated with negative health outcomes, yet little is known about the underlying molecular mechanisms. Method: RNA sequencing was conducted using blood samples from 15 individuals with primary insomnia and 15 age- and gender-matched good sleeper controls. The RNA library was sequenced with 150 base pair paired-ends on the Illumina NovaSeq-6000 platform. Alignment was performed using human reference genome hg38. Differential gene expression analysis was performed using DESeq2 following alignment, using log fold change ±0.50, and had a false discovery rate p-value 40) with genes and hubs related to inflammation (nuclear factor-kB), oxidative stress (Mitochondrial complex 1) and ubiquitination. Conclusion: Differentially expressed genes in this analysis are functionally associated with inflammation and immune response, mitochondrial and metabolic processes. Further research into the transcriptomic changes in insomnia is needed to understand related pathways to the disorder and provide new avenues for diagnostics and therapeutics.
Menstrual cycle length and modern living: a review.

Purpose of review The aim of this review is to evaluate biological, life history, environmental, and lifestyle factors and exposures that cause variability in menstrual cycle length (MCL). Recent findings Recent literature has detailed a number of factors that influence MCL, with particular emphasis placed on novel environmental exposures, such as air pollution and endocrine disrupting chemicals. Summary MCL varies widely in response to intrinsic and extrinsic inputs and is a useful predictor of reproductive health and fecundability. Video abstract http://links.lww.com/COE/A28.
Nomination and list placement of ethnic minorities under open-list proportional rules: The centrality of ethnopolitical context

Abstract Do parties respond to ethnopolitical context when nominating and placing ethnic minority candidates in open-list proportional representation (PR) systems? Open-list PR is by nature candidate centered. Candidates need to attract preference votes to succeed. Political leaders, we argue, anticipate candidates' ability to generate support and the extent of anti-minority sentiment in districts when nominating and placing candidates. To test our arguments, we analyze data on 8945 candidates competing across 124 localities in Latvia's 2017 local elections. Few studies have explored open-list systems in countries like Latvia where preference voting routinely alters list order. Other studies stress the role that context plays in ethnic minority representation, but often lack data on crucial indicators. Our results show that parties nominated more minority candidates in localities with more ethnic minority voters and fewer in those with larger noncitizen populations. We did not, however, find that ethnopolitical context affected list placement.
Genome-wide distribution of 5hmC in the dental pulp of mouse molars and incisors.

The dental pulp is critical for the production of odontoblasts to create reparative dentin. In recent years dental pulp has become a promising source of mesenchymal stem cells that are capable of differentiating into multiple cell types. To elucidate the transcriptional control mechanisms specifying the early phases of odontoblast differentiation, we analyzed the DNA demethylation pattern associated with 5-hydroxymethylcytosine (5hmC) in the primary murine dental pulp. 5hmC plays an important role in chromatin accessibility and transcriptional control by modeling a dynamic equilibrium between DNA methylation and demethylation. Our research revealed 5hmC enrichment along genes and non-coding regulatory regions associated with specific developmental pathways in the genome of mouse incisor and molar dental pulp. Although the overall distribution of 5hmC is similar, the intensity and location of the 5hmC peaks significantly differs between the incisor and molar pulp genome, indicating cell type-specific epigenetic variations. Our study suggests that the differential DNA demethylation pattern could account for the distinct regulatory mechanisms underlying the tooth-specific ontogenetic programs.
Airborne laser ranging system for monitoring regional crustal deformation

Alternate approaches for making the atmospheric correction without benefit of a ground-based meteorological network are discussed. These include (1) a two-color channel that determines the atmospheric correction by measuring the time delay induced by dispersion between pulses at two optical frequencies; (2) single-color range measurements supported by an onboard temperature sounder, pressure altimeter readings, and surface measurements by a few existing meteorological facilities; and (3) inclusion of the quadratic polynomial coefficients as variables to be solved for along with target coordinates in the reduction of the single-color range data. It is anticipated that the initial Airborne Laser Ranging System (ALRS) experiments will be carried out in Southern California in a region bounded by Santa Barbara on the norht and the Mexican border on the south. The target area will be bounded by the Pacific Ocean to the west and will extend eastward for approximately 400 km. The unique ability of the ALRS to provide a geodetic 'snapshot' of such a large area will make it a valuable geophysical tool.
Criterion-referenced Language Testing: Criterion-referenced test items

Introduction In his review of Roid and Haladyna (1982), Nitko (1984) notes that: Although techniques for creating test items are traditionally covered in measurement textbooks, much of what novice item writers read in these textbooks is “clinical lore”: Elder item-writers pass down to novices lists of rules and suggestions which they and their item-writing forefathers have learned through the process of applied art, empirical study and practical experience, (p. 201) Without accepting the mantle of “elder item-writers”, we would venture to propose that a set of general rules, which can be modified to help in writing good tests, has already been suggested for the area of discourse interpretation. These rules, called Grice's Maxims for the Cooperative Principle of Discourse (Grice, 1975), are related to quantity, quality, relation, and manner of general discourse, but they can also be used to cover the cooperative nature of test writing. The maxims can be summarized as follows: Make your contribution as informative as is required but not more informative than required. Be relevant. Avoid ambiguity and obscurity of expression. Be orderly. Therefore, in writing test items and instructions: do not explain too much; do not use trick questions; provide only the information necessary; avoid ambiguity; and be orderly in test presentation. Remember that the examinees will assume that you are presenting them with all, and only, the relevant information.
Saddlepoint Approximations with Applications: Bootstrapping in the transform domain

Sometimes nonparametric bootstrap inference can be performed by using a saddlepoint inversion to replace the resampling that is normally required. This chapter considers this general concept and pursues the extent to which the general procedure can implemented. The main set of examples have been taken from Butler and Bronson (2002) and Bronson (2001). They involve bootstrap inference for first passage characteristics and time to event distributions in the semi-Markov processes discussed in chapter 13. Saddlepoint approximations of nonparametric bootstrap estimates are given for the mean and standard deviation of first passage and as well as for the density, survival, and hazard functions associated with the passage events. Thus saddlepoint approximations become estimates for these moments and functions and represent approximations to the estimates that would normally be provided were a large amount of resampling to be implemented with “single” bootstrap resampling. In performing these computations however, no resampling has been used to compute the estimates, only saddlepoint inversions. The saddlepoint estimates utilize data from the process through an empirical estimate T ( s ) of the unknown system transmittance matrix T ( s ). Empirical transmittance T ( s ) is used in place of T ( s ) when implementing the saddlepoint inversions. In addition to bootstrap estimates, confidence intervals for the moments and confidence bands for the functions may be computed by using the double bootstrap. Often the resampling demands inherent in the double bootstrap place its implementation beyond the range of practical computing (Booth and Presnell, 1998).
PLAQUE DIFFERENTIATION AND REPLICATION OF VIRULENT AND ATTENUATED STRAINS OF MEASLES VIRUS

Abstract Rapp, Fred (Baylor University College of Medicine, Houston, Tex.). Plaque differentiation and replication of virulent and attenuated strains of measles virus. J. Bacteriol. 88:1448–1458. 1964.—Plaque formation by strains of measles virus in a stable line of African green monkey kidney cells (BSC-1) is characterized by development of large plaques (>1 mm) within 4 days after inoculation of the cultures with the virulent Edmonston strain or by small plaques (<1 mm) after inoculation with the attenuated Edmonston strain of virus. Plaque formation by measles virus is not influenced by iododeoxyuridine, cytosine arabinoside, isatinthiosemicarbazone, streptonigrin, actinomycin D, or mitomycin C. The predominant cytopathic effect observed with both strains is the formation of large, multinucleated giant cells. Development of the giant cells is correlated with development of virus antigen and synthesis of infectious virus. Synthesis of virus is similar at 34 and at 37 C. Appearance of intracellular virus precedes release, and is later in the attenuated virus-infected cells than in cells infected with the virulent strain. With the virulent strain, equal concentrations of intra- and extracellular virus are found but, with attenuated virus, only a small fraction reaches the extracellular fluids, and more than 95% of the newly synthesized virus remains cell-associated.
Characterization of a circular plasmid from Borrelia burgdorferi, etiologic agent of Lyme disease.

Borrelia burgdorferi, the etiologic agent of Lyme disease, was recently shown to contain plasmid DNA. Two plasmid species have been described in strain CT1, a Wisconsin tick isolate: a 9.2-kilobase entity; and a larger, 70-kilobase entity. Characterization of the 9.2-kilobase entity by using DNase I and restriction endonucleases demonstrated that the plasmid is supercoiled and exists as a stable dimer in this strain. The role played by the plasmid in B. burgdorferi is unknown. Images
A deep level reasoning tool for semiconductor process simulation

Summary form only given. An approach is proposed which attempts to combine features found in traditional process simulators and expert systems. The result is a system which generates process-specific knowledge from physical models by the sequential execution of a process recipe. This deep-level knowledge can be used in conjunction with techniques borrowed from the artificial intelligence community to reason about a variety of domain problems. Dependency trees are generated by the sequential execution of a process recipe. These trees can be used for identifying relationships between process steps and structures, which is useful in a problem-solving domain. The system design has been optimized for speed by using both analytical and empirical models. Typical recipes can be simulated in approximately one minute. Accuracy is achieved by providing a tuning mechanism which allows the user to input actual process data as a goal for the system output. The program described offers a logical evolution over traditional simulators and should find future applications in process control and failure analysis. >
Environmental threats to children's health: a challenge for pediatrics: 2000 Ambulatory Pediatric Association (APA) Presidential Address.

Public health accomplishments have dramatically improved children's lives. Sanitation programs, vaccines, better nutrition, surveillance and monitoring of disease, and the development of antibiotics have led to extraordinary reductions in infant and child mortality.1 Ambulatory pediatricians have contributed, through research, teaching, and advocacy, and especially through the delivery of improved medical care to this dramatic trend. Despite these advances, children are in trouble:
Composite transposable elements in the Xenopus laevis genome.

Abstract Members of two related families of transposable elements, Tx1 and Tx2, were isolated from the genome of Xenopus laevis and characterized. In both families, two versions of the elements were found. The smaller version in each family (Tx1d and Tx2d) consisted largely of two types of 400-base-pair tandem internal repeats. These elements had discrete ends and short inverted terminal repeats characteristic of mobile DNAs that are presumed to move via DNA intermediates, e.g., Drosophila P and maize Ac elements. The longer versions (Tx1c and Tx2c) differed from Tx1d and Tx2d by the presence of a 6.9-kilobase-pair internal segment that included two long open reading frames (ORFs). ORF1 had one cysteine-plus-histidine-rich sequence of the type found in retroviral gag proteins. ORF2 showed more substantial homology to retroviral pol genes and particularly to the analogs of pol found in a subclass of mobile DNAs that are supposed retrotransposons, such as mammalian long interspersed repetitive sequences, Drosophila I factors, silkworm R1 elements, and trypanosome Ingi elements. Thus, the Tx1 elements present a paradox by exhibiting features of two classes of mobile DNAs that are thought to have very different modes of transposition. Two possible resolutions are considered: (i) the composite versions are actually made up of two independent elements, one of the retrotransposon class, which has a high degree of specificity for insertion into a target within the other, P-like element; and (ii) the composite elements are intact, autonomous mobile DNAs, in which the pol-like gene product collaborates with the terminal inverted repeats to cause transposition of the entire unit.
A Reverse Gaussian deployment strategy for intrusion detection in wireless sensor networks

Intrusion detection is one of many typical applications for wireless sensor networks (WSNs). A WSN for intrusion detection application is capable of detecting any physical existence of external intruder invading an area under protection and alert the system for appropriate actions. Traditional deployment schemes for intrusion detection usually consider detection probability of having separate facilities within the monitored area. In this work, we assume that the scenario includes multiple facilities. A Reverse Gaussian distribution is derived from two dimensional Gaussian distribution and sensors are deployed following a Reverse Gaussian distribution. By placing a larger number of sensor nodes at the border, the detection probability is enhanced. As intrusion attacks start from border area, Reverse Gaussian deployment scheme can provide a better security performance with the same amount of investment as compared to traditional deployment schemes, and is validated by extensive simulation results.
Multiple collision analysis of total cross sections for Ar-L and Mg-K vacancy production measured in slow Ar-Mg collisions☆

Abstract Total vacancy production cross sections resulting from multiple collisions of 50–500 keV Ar2+,1+ with Mg in thick targets were determined from the characteristic Mg-K and Ar-L X-ray yields measured with a gas-flow proportional counter. The cross sections were corrected for Ar-straggling, and the Mg-K vacancy production cross sections were further corrected for target-target recoil effects. The Ar-L vacancy production cross sections are compared with the cross sections calculated from 3dδ+−3dπ+−3dσ rotational coupling. The theoretically calculated 2pπ−2pσ rotational coupling cross section is used to determine the equilibrium fraction of Ar-L vacancies in these collisions. The Mg-K and Ar-L results are used finally to determine the average lifetime and average fluorescence yield of the Ar-L vacancy.
The Reissner-Sagoci Problem for the Transversely Isotropic Half-Space

This paper evaluates the elastic field in a transversely isotropic half-space caused by a circular flat bonded punch under torsion loading. The elastic field is found by integrating the point force potential functions. For the case of isotropy the present results agree with previous analysis.
Effect of tungsten substitution in the YBa2Cu3O7−x system

A series of YBa2Cu3−x oxides was synthesized. The results show a cubic system with a simple perovskite structure for x 0.2. There was no indication of the existence of the superconducting 1-2-3 phase for x > 0.2. Solid solution of tungsten was exhibited over the composition region 0.2 < x as well as in the simple perovskite composition range. Analyses of a sample of nominal composition YBa2Cu2W oxide indicates a non-superconducting perovskite with a0 = 8.343 A.
Tree-based recursive partitioning methods for subdividing sibpairs into relatively more homogeneous subgroups.

We propose a new splitting rule for recursively partitioning sibpair data into relatively more homogeneous subgroups. This strategy is designed to identify subgroups of sibpairs such that within-subgroup analyses result in increased power to detect linkage using Haseman-Elston regression. We assume that the subgroups can be defined by patterns of non-genetic binary covariates measured on each sibpair. The data we consider consists of the squared difference of a quantitative trait measurement on each sibpair, estimates of identity-by-descent (IBD) values at each genetic marker, and binary covariate data describing characteristics of the sibpair (e.g., race, sex, family history of disease). To test the efficacy of this method in linkage analysis, we performed two simulation experiments. In the first, we simulated a mixture consisting of 66.6% of the sibpairs with no linkage and 33.3% of the sibpairs with genetic linkage to one marker. The two groups were distinguished by the value of a single binary covariate. We also simulated one unlinked marker and one random covariate to include as noise in the data. In the second experiment, we simulated a mixture consisting of 55% of the sibpairs with no genetic linkage, 22.5% of the sibpairs with genetic linkage to one marker, and 22.5% of the sibpairs with linkage to a different marker. Each subgroup was defined by a distinct pattern of two binary covariates. We also simulated one unlinked marker and two random covariates to include as noise in the data. Our simulation studies found that we can significantly increase the overall power to detect linkage by fitting Haseman-Elston regression models to homogeneous subgroups with only a small increase in the false-positive rate. Second, the splitting rule can correctly identify important covariates and linked markers. Third, recursive partitioning of sibpair data using this splitting rule can correctly identify sibpair subgroups. These results indicate that partitioning sibpairs into homogeneous subgroups is feasible and significantly increases the power to detect linkage, thus demonstrating the practical utility and potential this new methodology holds.
On the asymptotic properties of parameter estimates in a regression model with non-normally distributed errors

As pointed out in a recent paper by Amirkhalkhali and Rao (1986) (henceforth referred to as A&R), the usual assumption of normality for the error terms of a regression model isoften untenable. However, when this assumption is dropped, it may be difficult to characterize parameter estimates for the model. For example, A&R (p. 189) state that “if the regression errors are non-normal, we are not even sure of their [e.g., the generalized least squares parameter estimates1] asymptotic properties.” A partial answer, however, is given by Spall and Wall (1984), which presents an asymptotic distribution theory for Kalman filter estimates for cases where the random terms of the state space model are not necessarily Gaussian. Certain of these asymptotic distribution results are also discussed in Spall (1985) in the context of model validation (diagnostic checking)
Active fatigue control of adhesive bonded joints

This paper investigates the concept of active fatigue control of an adhesively bonded structure. Adhesive bonding has recently become very widely used, especially with the gaining popularity of composite materials. The adhesive bonds are usually the weakest link in the entire bonded structure. Additionally, one of the major causes of failure in the bond is fatigue. With increasing knowledge in the field of intelligent material systems, it is now possible to reduce the stress in the adhesive bond by using induced strain actuators, such as PZT. Experimental results show that the fatigue life of a vibrating, cantilever beam with an adhesive bond can be increased by nearly an order of magnitude with active fatigue control. This paper presents an analytical model which can be used to determine the correct control schemes of induced strain actuators on a cantilever beam vibrating over a range of frequencies. With proper control, the peeling stresses in the adhesive bond can be minimized for a broad frequency range.
The intersection of race and gender in school leadership for three Black female principals

Using four assumptions of Black feminism, this qualitative study describes the practice of three African-American female principals in predominantly African-American, urban high schools. First, in general, the principals seemed to understand their experiences as part of a larger historical context. Second, given the shared racial and gender identities, the principals described several commonalities within their lived experience. Third, differences in age and context affected the leadership practices and experiences encountered by these principals. Fourth, the principals exhibited a non-monolithic response to the identification of injustice and oppression. Further, while the principals all seemed to understand the various injustices that existed within their educational setting, they tended to respond in more tempered radical ways.
Propagation of surface waves across a vertical layer with non-rigid contacts

Abstract Propagation of surface waves across a vertical wave barrier inserted between two laterally homogeneous quarter-spaces is considered in this paper. Based on the Green's function technique, an analytical approach is developed to examine the reflection and transmission of Rayleigh surface waves across a composite barrier. The composite barrier consists of a high velocity layer sandwiched between two thin layers of low shear velocity materials. The high velocity layer is represented by differential matrix operators which relate the wave fields on each side of the layer. The low velocity layers are modeled by non-rigid or “unwelded” contact conditions which allow partial sliding at the interfaces. Screening ratios of barriers with various combinations of material, geometric, and non-rigidness parameters are compared and discussed in some detail.
Infrared Spectroscopy of Faint High Galactic Latitude Carbon Stars

Carbon stars at high Galactic latitudes used to study the kinematics of the Galactic halo are difficult to distinguish from nearby dwarf carbon (dC) stars at intermediate spectral resolution. This paper presents near-infrared spectra of a sample of carbon stars that show that the CO first-overtone bands are far weaker in the known dC stars than in giants for a given H-K color. This finding, along with the unusual location of dC stars in the JHK color-color diagram, may be explained by the effects of collision-induced absorption, which is predicted, in stars of low metallicity and high surface gravity, to greatly suppress molecular absorption features in the near-infrared.
N-(2,3-dimercaptopropyl)phthalamidic acid (DMPA) increases polonium-210 excretion.

Polonium-210 is one of the most hazardous radionuclides. As recently as 1988, there have been concerns regarding accidental exposures of humans to it. Yet, there have been no studies on the effectiveness of the newer dithiol chelating agents in increasing the excretion of this radioactive heavy metal. In order to accomplish this, a safe and effective method for determining the radioactivity of polonium-210, an a emitter, in the feces was developed. The excretion of polonium-210 was studied by giving male Sprague-Dawley rats210Po (3.33 × 107 cpm/kg, intraperitoneal); 1 h later they were given either 5% sodium bicarbonate,N-(2,3-dimercap-topropyl)phthalamidic acid (DMPA) ormeso-dimercaptosuccinic acid (DMSA) (0.20 mmol/kg, subcutaneous). Treatment was repeated daily for 12 days. DMPA and DMSA increased the urinary excretion of210Po, as compared to control animals, 8-fold and 5-fold, respectively. DMPA increased the fecal excretion of210Po compared to the other treatments and also decreased the level of210Po in the spleen, a radiosensitive organ. DMPA (0.20 mmol/kg, intravenous) increased biliary levels of210Po 5-fold compared to controls. The results indicate that DMPA has greater specificity in chelating and increasing the excretion of210Po than DMSA.
Unraveling the myth of meritocracy within the context of US higher education

Framed by historical and contemporary discussions, this article reviews the principal foundations of meritocracy and uses the public University of California system as a point of departure for examining the connection between meritocracy and higher education within the context of the United States. Through consideration of four dimensions that inform the concept of meritocracy—merit, distributive justice, equality of opportunity, and social mobility—this review examines the underlying tenets of meritocracy to better understand how higher education functions within it. In The Coming of Post-Industrial Society, Daniel Bell (1973) suggested that higher education would become a “defensive necessity.” However, if colleges and universities are to serve as instruments for creating and expanding opportunity, then higher education must be more profound than simply being reduced to “defensive necessity,” and it is important for researchers to examine more closely the theoretical concerns of meritocracy and the higher education implications.
Science and certainty

Dans la pratique scientifique courante, la certitude est accordee aux principes de base d'une science mature et on dit que cette certitude est fondee sur la preuve experimentale. L'A. cherche a demontrer la facon dont deux formes interliees de l'inference, induction demonstrative et induction eliminative, peuvent etre utilisees en appui de jugements de ce type. Suit une illustration de leur application en discontinuite quantique au debut de ce siecle
Amazon diversity in light of the paleoecological record

Abstract Disjunct distributions of Amazonian species have been explained previously by a refugial theory which postulates that Amazonian rain forest was preserved in large highland regions throughout the Pleistocene. No direct, radiocarbon dated evidence exists for the last glacial maximum with which to test this theory. The only radiocarbon dates of Pleistocene age from the Amazon basin are of fossiliferous deposits in the proposed Napo refugium of the West, where both pollen assemblages and wood samples indicate that forest with cool Andean elements existed there at two intervals in the last cycle of northern hemisphere glaciation, implying a temperature depression of at least 4°C in the Amazon lowlands. Under modern climatic conditions, lateral erosion by river meander, together with surface erosion, serves as a rejuvenating mechanism for the rain forests of Peru and Ecuador. The instability of late Holocene Amazonian climates is demonstrated by documenting a precipitation event in the eastern Andean cordillera that caused widespread flooding of western Amazonian forests 800–1300 BP. Late Holocene pollen histories from widely dispersed parts of central Amazonia distinguish between vegetation histories in the drainage of northern, south-western and western watersheds, but all show histories of fluctuating intensities of dry seasons. Radiocarbon dating of charcoal layers in soils of Venezuelan Amazonia demonstrates the apparently random incidence of wild fires at wide intervals over at least the last 6 ka. The high species richness of Amazonia is a result of numerous opportunities for vicariance because of a very large total area, wide variety of habitats and intermediate levels of disturbance, particularly by hydrological processes, that has varied on timescales from years to millennia. Amazonian disjunct distributions probably reflect regional environmental discontinuities in both interglacial and glacial times.
PROMIS Pediatric Pain Interference Scale: an item response theory analysis of the pediatric pain item bank

Abstract An aim of the National Institutes of Health (NIH) Patient Reported Outcomes Measurement Information System (PROMIS) initiative is to develop item banks and computerized adaptive tests (CAT) that are applicable across a wide variety of chronic disorders. The PROMIS Pediatric Cooperative Group has concentrated on the development of pediatric self-report item banks for ages 8 through 17 years. The objective of the present study is to describe the Item Response Theory (IRT) analysis of the NIH PROMIS pediatric pain item bank and the measurement properties of the new unidimensional PROMIS Pediatric Pain Interference Scale. Test forms containing pediatric pain items were completed by a total of 3048 respondents. IRT analyses regarding scale dimensionality, item local dependence, and differential item functioning were conducted. A pain item pool was developed to yield scores on a T -score scale with a mean of 50 and standard deviation of 10. The recommended 8-item unidimensional short form for the PROMIS Pediatric Pain Interference Scale contains the item set which provides the maximum test information at the mean (50) on the T -score metric. A simulated CAT was computed that provides the most information at 5 possible score locations (30, 40, 50, 60, and 70 on the T -score metric). Perspective The present study provides initial calibrations of the NIH PROMIS pediatric pain item bank and the creation of the PROMIS Pediatric Pain Interference Scale. It is anticipated that this new scale will have application in pediatric chronic and recurrent pain.
Antimicrobial susceptibility, tolerance, and synergy of groups A and B streptococci

Abstract Although group A and B streptococci have similar susceptibility to antimicrobics, group A streptococci are killed significantly faster at clinically relevant concentrations of penicillin or ampicillin. The addition of an aminocyclitol to either penicillin or ampicillin enhances the rate of killing of streptococci. Because the rate of killing of group B streptococci is significantly increased by the addition of gentamicin at concentrations of 0.1 μg and 0.5 μg/ml to either penicillin or ampicillin, the use of combined therapy may indeed be beneficial in the initial treatment of group B streptococcal meningitis. However, as meningeal inflammation subsides, gentamicin may not enter the central nervous system well enough to justify continued use. Combined therapy for the duration of treatment of penicillin-tolerant group B streptococci has been recommended on the basis of isolated case reports of relapse after single drug therapy. This approach is not supported by in vitro observations of no enhancement of the rate of killing of tolerant strains by the addition of gentamicin to penicillin. Thus, a final recommendation regarding the duration of combined therapy, and use with tolerant organisms, awaits further studies.
Lick Observatory adaptive optics wavefront sensor upgrades

The wavefront sensor camera and tip/tilt sensor APDs that were on Lick Observatory's Shane 3 Meter Adaptive Optics system were over a decade old and showing their age. They were recently upgraded. The first upgrade was to convert from quad-APDs in the laser guidestar mode natural star tip-tilt sensor to a sensitive low-noise CCD. The new CCD in this position, an 80x80 E2V CCD-39 inside a SciMeasure camera, has a low enough read noise, ~3 e-/pixel, that the tip/tilt measurement in closed-loop operation is photon noise limited and thus benefits from the improved quantum efficiency of the CCD. We have demonstrated on-sky up to two magnitudes of improvement in viable tip/tilt star brightness, which greatly extends the available sky coverage in the laser guidestar AO mode. Also, the increased field of view of the new tip/tilt sensor provides a much more reliable means of acquiring and locking on dim tip/tilt stars, making the whole system operationally more efficient. In the second phase of the upgrade project, the high order wavefront sensor has been replaced, also with a CCD-39 chip in a SciMeasure camera. In this paper we will describe these upgrades and present preliminary performance results.
The Structure-Function Analysis of Myosin Pseudo-Phosphorylation in Mouse Model of FHC

Familial hypertrophic cardiomyopathy (FHC) is a disease of the heart caused by autosomal dominant mutations in genes coding for all major sarcomeric proteins, including the myosin regulatory light chain (RLC). In this report, we have explored the rescue strategies to ameliorate the malignant cardiomyopathy phenotype induced by an aspartic acid to valine substitution (D166V) in the RLC. Previous studies on porcine reconstituted preparations showed that the phosphorylation mimic (S15D) in the background of the D166V mutation (S15D-D166V) restored the calcium sensitivity of force and improved Vmax of myosin ATPase that were largely compromised by the D166V mutation. Transgenic "Rescue Mice" carrying the S15D-D166V mutation have been generated and subjected to structural and functional measurements. Small angle X-ray studies on freshly skinned papillary muscle fibers revealed that a D166V-induced reorganization in cross-bridge mass distribution was partially reversed in Rescue Mice (abnormally increased I1,1/I1,0 ratio observed in Tg-D166V fibers returned to the value near Tg-WT). Noteworthy, pseudo-phosphorylation of D166V significantly restored fiber elasticity allowing for changes in the cross-bride mass distribution on stretch. In vivo cardiac morphology and function were assessed by non-invasive echocardiography followed by invasive left ventricular pressure-volume measurements (P-V loops). Echocardiography assessment confirmed hypertrophy in Tg-D166V mice showing an increased posterior wall thickness in systole. Invasive hemodynamics showed diastolic and systolic dysfunction in Tg-D166V mice. The end-systolic P-V relationship, a measure of heart contractility, which was largely reduced in Tg-D166V mice was completely ameliorated in Rescue Mice. In addition, the maximum dP/dt - End-Diastolic Volume relation, which was compromised in Tg-D166V was fully reversed in Rescue Mice. In conclusion, our results suggest that pseudo-phosphorylation of myosin RLC can mitigate both the structural and functional abnormalities of the FHC heart. Supported by NIH-HL108343 and HL071778 (DSC).
APC mutations occur early during colorectal tumorigenesis.

HUMAN tumorigenesis is associated with the accumulation of mutations both in oncogenes and in tumour suppressor genes1–3. But in no common adult cancer have the mutations that are critical in the early stages of the tumorigenic process been defined. We have attempted to determine if mutations of the APC gene play such a role in human colorectal tumours, which evolve from small benign tumours (adenomas) to larger malignant tumours (carcinomas) over the course of several decades. Here we report that sequence analysis of 41 colorectal tumours revealed that the majority of colorectal carcinomas (60%) and adenomas (63%) contained a mutated APC gene. Furthermore, the APC gene met two criteria of importance for tumour initiation. First, mutations of this gene were found in the earliest tumours that could be analysed, including adenomas as small as 0.5 cm in diameter. Second, the frequency of such mutations remained constant as tumours progressed from benign to malignant stages. These data provide strong evidence that mutations of the APC gene play a major role in the early development of colorectal neoplasms.
Effects of Frequency in Classroom Second Language Learning: Quasi-Experimental and Stimulated-Recall Analysis by TODE, TOMOKO.

The article reviews the book "Effects of Frequency in Classroom Second Language Learning: Quasi-Experimental and Stimulated-Recall Analysis," by Tomoko Tode.
Scanning tunneling measurements of potential steps at grain boundaries in the presence of current flow

We have used a new technique to simultaneously measure the surface topography and surface potential of current-carrying polycrystalline Au 60 Pd 40 thin films using a scanning tunneling microscope. We find abrupt steps in the surface potential due to scattering from grain boundaries in these films.
Movement disorders and lesions of pigeon brain stem analogues of basal ganglia.

Abstract The nucleus spiriformis lateralis (SpL) and the nucleus tegmenti pedunculo-pontinus, pars compacta (TPc) of the pigeon are thought to be analogous to the mammalian substantia nigra. The analogy is based upon comparative neuroanatomical and histochemical similarities. To test the analogy on a behavioral basis, unilateral electrolytic or kainate lesions were produced in selected nuclei of the diencephalon and mesencephalon. Birds demonstrated behaviioral disturbances similar to those induced in mammals after lesions to the substantia nigra. The most obvious disturbance was a persistent turning in a direction opposite to the side of the lesion. The birds also demonstrated postural problems and arhythmic movements of the head or whole body tremor. The similarities in movement disorders strengthen on a behavioral basis, the suggested analogies between the mammalian substantia nigra and the SpL and TPc. The pigeon may be another useful experimental model to study movement disorders associated with damage to the basal ganglia.
Cumulative antiplatelet effect of low‐dose enteric coated aspirin

Enteric coated aspirin (ECA) at doses of 325-1300 mg is an effective alternative to regular aspirin for inhibition of platelet activity while avoiding gastric irritation. The objectives of this study were to determine: (1) the lowest chronic dose of ECA providing effective inhibition of platelet activities, (2) the time course of the inhibition, and (3) the reappearance of platelet cyclo-oxygenase activity. Seven subjects were studied before and after seven daily doses of 40-325 mg ECA. Serum thromboxane (TX) B2 levels indicated that the lowest dose of ECA resulting in greater than 90% inhibition of platelet cyclo-oxygenase was 80 mg/d. Platelet aggregation and ATP release in response to collagen (1 microgram/ml) and arachidonic acid (1 mM) were abolished and bleeding times were prolonged from 6.1 +/- 1.5 min to 9.7 +/- 2.8 min (mean +/- SD, P less than 0.01). Examination of platelet cyclo-oxygenase activity on a daily basis revealed that 24 h after the first 80 mg dose serum TXB2 had decreased by approximately 60% and was suppressed by more than 90% after four doses. Recovery of platelet cyclo-oxygenase activity after a single 80 mg dose of ECA was delayed for 48-72 h indicating that aspirin reached the systemic circulation. We conclude that chronic inhibition of platelet activity may be achieved in a cumulative manner with 80 mg ECA/d.
A stiffness matrix method for foot force distribution of walking vehicles

The authors formulate a compliance model of walking systems and develop a stiffness matrix method for their foot force distribution by considering leg structure, actuators, and terrain as compliant, and incorporating the compatibility condition of deformation into equilibrium equations. To demonstrate the method in an actual machine, the stiffness matrix of a walking machine with pantograph legs is derived analytically, and numerical results for a quadruped walking with different gaits are presented and discussed. Compared with previous approaches, this method is considered to be more realistic, since it satisfies material deformation laws. Moreover, it is computationally very efficient and can be used in real-time control or simulation. >
Affinity-Testing in Initial Interactions

Previous research has suggested that, during first encounters, conversation performs an uncertainty reducing function and persons' selections of conversational strategy require `trade-offs' between efficiency and social appropriateness. Moreover, uncertainty reduction is posited to induce increased liking for a target. However, relationship development is contingent upon mutual liking so that initial interactants may commonly seek out information concerning others' affective judgments. This analysis was designed to (1) demonstrate that previously explicated information-seeking behaviours (e.g., inter-rogation, disclosure) are likely to provide limited access to those judgments; (2) define the ways in which initial interactants test targets' affinity; and (3) determine the extent to which these tests involve compromise between efficiency and social appropriateness.
Diffraction by a right-angled dielectric wedge

Abstract The problem considered is that of determining the field of a plane wave of transverse magnetic type in the presence of a right-angled dielectric wedge. An explicit solution is derived, and shown to be unique. Field behavior at the corner of the wedge is discussed. The analysis, an extension and refinement of earlier work of the author, is in essence a generalization of the function-theoretical method of Wiener and Hopf from one to two complex variables.
Are college students adults? Their conceptions of the transition to adulthood

College students (N=346) were surveyed on their conceptions of the transition to adulthood and their own status as adults. Only 23% indicated that they considered themselves to have reached adulthood, while nearly two-thirds indicated that they considered themselves to be adults in some respects but not in others. The most important criteria for marking the transition to adulthood were indicated to be individualistic and intangible criteria, particularly “accept responsibility for the consequences of your actions,” “decide on beliefs and values independently of parents or other influences,” and “establish a relationship with parents as an equal adult,” each of which was endorsed by more than 70% of the sample. In contrast, role transitions such as completing education, marriage, and becoming a parent were endorsed by less than 20%. It is suggested that the transition from adolescence to adulthood in Western societies is a process that may last many years, during which individualistic and intangible markers of adulthood (such as those specified here) are gradually and incrementally pursued.