cssi/SciSciGPT-SciSciNet huggingface dataset:
RECURRING THEMES IN OOCYTE MATURATION

I am pleased to contribute to this special issue of Biology of the Cell in honor of Yoshio Masui. Oocyte maturation remains a small enough and young enough field that the authors assembled for this issue can trace the entire development of the field over the last 30 years, beginning with the early demonstration by Masui (1967) and others that steroids can induce complete maturation of denuded oocytes in vitro. Not very long after that Masui and Markert (1971) published the seminal paper that identified MPF and CSF activity. In this article I intend to highlight recurring themes in oocyte maturation that continue to be actively investigated, almost all of which derive from studies pursued at some point in time by Masui and his colleagues.
Spatial, Temporal, and Global Mode Entropy in a Thalamo-Cortical Network

We employ an orthogonal decomposition technique with unique space–time symmetry properties to analyze a network of thalamo–cortical oscillators. A small number of thalamic "cells" are used to drive a network of cortical cells structured on a two-dimensional lattice. Two Bonhoeffer–van der Pol (BVP) based models of cortical neurons are compared at the network level in an attempt to reproduce some features of the thalamo–cortical system. It is shown that with the addition of a slowly varying term to the classical two-dimensional BVP model, the network can exhibit both periodic and irregular space–time behavior, along with changes in the temporal coherence and spatial frequency resembling the 8–12 Hz alpha rhythm.
Dosage considerations for transcranial direct current stimulation in children: a computational modeling study

Transcranial direct current stimulation (tDCS) is being widely investigated in adults as a therapeutic modality for brain disorders involving abnormal cortical excitability or disordered network activity. Interest is also growing in studying tDCS in children. Limited empirical studies in children suggest that tDCS is well tolerated and may have a similar safety profile as in adults. However, in electrotherapy as in pharmacotherapy, dose selection in children requires special attention, and simple extrapolation from adult studies may be inadequate. Critical aspects of dose adjustment include 1) differences in neurophysiology and disease, and 2) variation in brain electric fields for a specified dose due to gross anatomical differences between children and adults. In this study, we used high-resolution MRI derived finite element modeling simulations of two healthy children, ages 8 years and 12 years, and three healthy adults with varying head size to compare differences in electric field intensity and distribution. Multiple conventional and high-definition tDCS montages were tested. Our results suggest that on average, children will be exposed to higher peak electrical fields for a given applied current intensity than adults, but there is likely to be overlap between adults with smaller head size and children. In addition, exposure is montage specific. Variations in peak electrical fields were seen between the two pediatric models, despite comparable head size, suggesting that the relationship between neuroanatomic factors and bioavailable current dose is not trivial. In conclusion, caution is advised in using higher tDCS doses in children until 1) further modeling studies in a larger group shed light on the range of exposure possible by applied dose and age and 2) further studies correlate bioavailable dose estimates from modeling studies with empirically tested physiologic effects, such as modulation of motor evoked potentials after stimulation.
Incidence of Medically Recognized Migraine: A 1989-1990 Study in Olmsted County, Minnesota

Objective.–To investigate the incidence of medically recognized migraine in Olmsted County, Minnesota, during the years 1989 to 1990. Methods.–We used the records-linkage system of the Rochester Epidemiology Project to identify all subjects who sought medical attention for their headache and had their initial visit for migraine within the study period. Incident cases were classified using specified criteria. Results.–From 9837 records screened, we found 713 incident cases. The average annual incidence rate (new cases per 100 000 person-years) was 343.0 in both sexes combined, 481.6 in women, and 194.4 in men. In women, incidence rates were low at the extremes of age and higher among those aged between 10 and 49 years, with a striking peak at the age of 20 to 29 years. Migraine without aura was the most common type of migraine in women. Men had a more constant risk of migraine throughout life with a lesser peak at the age of 10 to 19 years, and they were equally affected by all types of migraine. Women had consistently higher incidence rates than men at all ages, and there were strikingly higher incidence rates of migraine without aura in women than in men. Conclusions.–Although our incidence rates were restricted to medically recognized cases of migraine, we confirmed previously reported epidemiological patterns.
Parallel bisecting k-means with prediction clustering algorithm

In this paper, we propose a new parallel clustering algorithm, named Parallel Bisecting k-means with Prediction (PBKP), for message-passing multiprocessor systems. Bisecting k-means tends to produce clusters of similar sizes, and according to our experiments, it produces clusters with smaller entropy (i.e., purer clusters) than k-means does. Our PBKP algorithm fully exploits the data-parallelism of the bisecting k-means algorithm, and adopts a prediction step to balance the workloads of multiple processors to achieve a high speedup. We implemented PBKP on a cluster of Linux workstations and analyzed its performance. Our experimental results show that the speedup of PBKP is linear with the number of processors and the number of data points. Moreover, PBKP scales up better than the parallel k-means with respect to the dimension and the desired number of clusters.
Biological species and variation in Arthroderma.

The distinctive peridial appendages ofArthroderma were of little value for the delimitation of species. The peridial appendages as well as the conidia of certain species were so similar as to be value-less for the delimitation of species. Further, morphological and physiological variation was found to be as great within, as between, species. The usual morphological methods for classifying species were, therefore, inadequate and the concept of biological species was considered.
Assessing the Effectiveness of First Step to Success: Are Short-Term Results the First Step to Long-Term Behavioral Improvements?

This article reports on the effectiveness of First Step to Success, a secondary-level intervention appropriate for students in early elementary school who experience moderate to severe behavior pro...
Shame, guilt, and identity in men and women: the role of identity orientation and processing style in moral affects

Abstract In the current study, 200 women and 106 men (M age = 19.6 years old) completed measures of shame, guilt, identity-orientation, and identity-processing styles. Women reported greater shame and guilt than men. Zero-order and partial correlates indicated that for both women and men shame was related positively to a social identity (one’s public image as presented through roles and relationships) and a diffuse processing style (both self-relevant information and self-exploration about one’s identity is avoided), while guilt was related to personal identity (conceptualizing oneself as unique) and an information-oriented style (self-exploration of personal issues occurs). Integration of identity orientation and cognitive processing styles in relation to shame and guilt was discussed.
Computer-assisted surgical planning and automation of laser delivery systems

This paper describes a 'real time' surgical treatment planning interactive workstation, utilizing multimodality imaging (computer tomography, magnetic resonance imaging, digital angiography) that has been developed to provide the neurosurgeon with two-dimensional multiplanar and three-dimensional 'display' of a patient's lesion.
Symptoms of sleep disturbances among children at two general pediatric clinics

Abstract Objective: We assessed the frequency of childhood sleep problems at 2 general pediatric clinics. Study design: Parents of 1038 unselected children (554 boys) aged 2.0 to 13.9 years completed a validated Pediatric Sleep Questionnaire while waiting for appointments. Results: Habitual snoring was reported in 176 (17%) of the children. Criterion scores suggestive of sleep-disordered breathing were found in 115 (11%) of the children, in 29% of children at the clinic for neurologic indications, and in 21% of children at the clinic for noninfectious respiratory indications. Insomnia (ie, unrefreshing sleep or difficulty with sleep onset, sleep maintenance, or early morning awakening from sleep) was reported in 430 (41%) of the children; ≥2 symptoms were present in 191 (18%) of the children. Excessive daytime sleepiness was suggested in 148 (14%) of the children, and 390 (38%) had symptoms of sleep terrors, sleepwalking, or nocturnal bruxism. Conclusions: Sleep problems such as sleep-disordered breathing, insomnia, excessive sleepiness, and parasomnias are frequent among children seen at general pediatric practices. (J Pediatr 2002;140:97-102)
An O (log N ) algorithm to solve linear recurrences on hypercubes

Abstract The hypercube is one of the most appealing and successful topologies among the interconnection networks designed for parallel processing applications. Linear recurrences arise frequently in many useful and important engineering and scientific applications. Consequently, fast parallel algorithms to solve linear recurrences offer significant value to the scientific community. In this paper we describe an efficient collision-free algorithm to solve general first order linear recurrences of length N on an N-node hypercube network. The time complexity of this algorithm is shown to be O(log N). For linear recurrences of length s × N where s is an integer > 0, the time complexity is shown to be O(s log N).
Does computer-assisted surgery improve accuracy and decrease the learning curve in hip resurfacing? A radiographic analysis.

Background: Hip resurfacing is a technically demanding procedure in which accurate positioning of the femoral component is critical to the avoidance of early implant failures. The purpose of this study was to assess the accuracy of computer-assisted placement of the femoral component and to evaluate the impact of computer-assisted surgery on the learning curve associated with this procedure. Methods: The accuracy of positioning the femoral component was analyzed radiographically in hips undergoing resurfacing procedures performed by surgeons assigned to four different study groups: Group 1, in which the operations were performed with use of computer-assisted surgery by a fellowship-trained surgeon who was experienced in performing resurfacing arthroplasty (surgical experience, more than 250 hip resurfacings); Group 2, in which the operations were performed with use of computer-assisted surgery by senior residents who were inexperienced in performing resurfacing arthroplasty and who were closely supervised by faculty; Group 3, in which the operations were performed with use of conventional instruments by fellowship-trained faculty members; and Group 4, in which the operations were performed with use of computer-assisted surgery by a lesser experienced fellowship-trained faculty member (surgical experience, more than forty but less than seventy-five hip resurfacings) from Group 3. Results: The range of error in varus or valgus angulation that was observed for navigated procedures was 6° in Group 1, 7° in Group 2, and 5° in Group 4. Compared with the preoperative neck-shaft angle value, the mean postoperative stem-shaft angle value increased by a mean of 4.7° in Group 1, 7.2° in Group 2, 6.5° in Group 3, and 11.6° in Group 4. When compared with the use of standard instrumentation, the use of computer-assisted surgery reduced the number of outliers and facilitated valgus insertion. Conclusions: In the present study, computer-assisted surgery resulted in improved accuracy and precision in positioning the femoral component. In addition, computer-assisted surgery led to a reduction in the length of the learning curve for beginners in hip resurfacing and improved the surgeon's ability to perform this procedure safely. Level of Evidence: Therapeutic Level III. See Instructions to Authors for a complete description of levels of evidence.
The generalized Mackenzie distribution: Disorientation angle distributions for arbitrary textures

Abstract A general formulation for the disorientation angle distribution function is derived. The derivation employs the hyperspherical harmonic expansion for orientation distributions, and an explicit solution is presented for materials with cubic crystal symmetry and arbitrary textures. The result provides a significant generalization to the well-known Mackenzie distribution function [Mackenzie JK. Biometrika 1958;45:229] for materials with random crystal orientations. This derivation also demonstrates that the relatively new hyperspherical harmonic expansion provides access to results that have been inaccessible with the more traditional “generalized spherical harmonic” expansion that is in current use throughout the field.
Inhibition of Salmonella typhimurium by the products of tartrate metabolism by a Veillonella species

The inhibition of the growth of Salmonella typhimurium by a Veillonella species grown on media supplemented with tartrate was examined. Growth of Salmonella typhimurium was not inhibited by the concentrations of products metabolized by Veillonella cultures on media supplemented with 0 or 50 mmol l -1 of tartrate, but was inhibited on media supplemented with 100 or 150 mmol l -1 of tartrate. Inhibition of Salm. typhimurium was correlated with the increased production of acetate and propionate from tartrate by the Veillonella species.
On the Distribution of the Values of Quadratic L-Series in the Half Plane ... .

In this paper we consider the distribution in the half-plane σ>1/2 of the values of DirichletL-series formed with quadratic characters.
Clustering via diffusion adaptation over networks

Distributed processing over networks relies on in-network processing and cooperation among neighboring agents. Cooperation is beneficial when all agents share the same objective or belong to the same group. However, if agents belong to different clusters or are interested in different objectives, then cooperation can be damaging. In this work, we devise an adaptive combination rule that allows agents to learn which neighbors belong to the same cluster and which other neighbors should be ignored. In doing so, the resulting algorithm enables the agents to identify their grouping and to attain improved learning and estimation performance over networks.
Designing effective transfer functions for volume rendering from photographic volumes

Photographic volumes present a unique, interesting challenge for volume rendering. In photographic volumes, the voxel color is pre-determined, making color selection through transfer functions unnecessary. However, photographic data does not contain a clear mapping from the multi-valued color values to a scalar density or opacity, making projection and compositing much more difficult than with traditional volumes. Moreover, because of the nonlinear nature of color spaces, there is no meaningful norm for the multi-valued voxels. Thus, the individual color channels of photographic data must be treated as incomparable data tuples rather than as vector values. Traditional differential geometric tools, such as intensity gradients, density and Laplacians, are distorted by the nonlinear non-orthonormal color spaces that are the domain of the voxel values. We have developed different techniques for managing these issues while directly rendering volumes from photographic data. We present and justify the normalization of color values by mapping RGB values to the CIE L*u*v* color space. We explore and compare different opacity transfer functions that map three-channel color values to opacity. We apply these many-to-one mappings to the original RGB values as well as to the voxels after conversion to L*u*v* space. Direct rendering using transfer functions allows us to explore photographic volumes without having to commit to an a-priori segmentation that might mask fine variations of interest. We empirically compare the combined effects of each of the two color spaces with our opacity transfer functions using source data from the Visible Human project.
A multiple-block fuzzy logic-based electric water heater demand-side management strategy for leveling distribution feeder demand profile

Abstract This paper describes a multiple-block fuzzy logic-based demand-side management (DSM) strategy to shift the peaks of the residential electric water-heater power demand component of a distribution area from periods of high demand for electricity to off-peak hours. This is achieved by dividing the distribution area into several blocks and, controlling each block by a different fuzzy controller. Simulation results are presented to show the effectiveness of the proposed DSM strategy to shift the electric water-heater peak demand to off-peak periods and to level the utility distribution demand profile.
Rapid, Sensitive Bioluminescent Reporter Technology for Naphthalene Exposure and Biodegradation

A bioluminescent reporter plasmid for naphthalene catabolism (pUTK21) was developed by transposon (Tn4431) insertion of the lux gene cassette from Vibrio fischeri into a naphthalene catabolic plasmid in Pseudomonas fluorescens. The insertion site of the lux transposon was the nahG gene encoding for salicylate hydroxylase. Luciferasemediated light production from P. fluorescens strains harboring this plasmid was induced on exposure to naphthalene or the regulatory inducer metabolite, salicylate. In continuous culture, light induction was rapid (15 minutes) and was highly responsive to dynamic changes in naphthalene exposure. Strains harboring pUTK21 were responsive to aromatic hydrocarbon contamination in Manufactured Gas Plant soils and produced sufficient light to serve as biosensors of naphthalene exposure and reporters of naphthalene biodegradative activity. The robust and sensitive nature of the bioluminescent reporter technology suggests that new sensing methods can be developed for on-line process monitoring and control in complex environmental matrices.
Autologous Immune-Complex Pathogenesis of Experimental Allergic Glomerulonephritis

A renal tubular epithelial antigen is deposited in association with gamma globulin and complement in glomeruli from rats with experimental allergic glomerulonephritis induced by immunization with renal tubular antigens. Apparently, in normal kidneys this antigen is concentrated in the distal segment of the proximal convoluted tubular epithelium, and the principal source of this antigen in the glomerular deposits is autologous. This form of glomerulonephritis provides an experimental prototype for what may be termed "autologous immunecomplex" diseases.
Tumor detection using folate receptor-targeted imaging agents

Folate receptors are up-regulated on a variety of human cancers, including cancers of the breast, ovaries, endometrium, lungs, kidneys, colon, brain, and myeloid cells of hematopoietic origin. This over-expression of folate receptors (FR) on cancer tissues can be exploited to target folate-linked imaging and therapeutic agents specifically to FR-expressing tumors, thereby avoiding uptake by most healthy tissues that express few if any FR. Four folate-targeted therapeutic drugs are currently undergoing clinical trials, and several folate-linked chemotherapeutic agents are in late stage preclinical development. However, because not all cancers express FR, and because only FR-expressing cancers respond to FR-targeted therapies, FR-targeted imaging agents have been required to select patients with FR-expressing tumors likely to respond to folate-targeted therapies. This review focuses on recent advances in the use of the vitamin folic acid to target PET agents, gamma-emitters, MRI contrast agents and fluorescent dyes to FR(+) cancers for the purpose of diagnosing and imaging malignant masses with improved specificity and sensitivity.
Chemical Composition and Buoyancy of Midwater Crustaceans as Function of Depth of Occurrence off Southern California

Water, ash, C, H, N, lipid, carbohydrate, chitin and protein contents were determined for 28 species of midwater crustaceans. Variation of these components as a function of depth of occurrence, relative buouancy and respiratory rate of these species was examined. Vertical distribution data for 10 of the species based on discrete depth crawls is provided. The relative bouyancies of 16 of these species were measured. The caloric contents of 21 species were calculated. Lipid content (percent wet weight) and caloric density increased at intermediate depths, but apparently decreased at the greatest depths; it is suggested that this decrease is related to the relatively large size of these organisms and the energy limiting conditions in the deep-sea. Protein content (percent wet weight) decreases with increasing depth of occurrence, and is apparently related to a substantial fraction of the decrease in respiratory rate with increasing depth of occurrence in these species. Within the range of values examined, relative buoyancy appeas to be independent of metabolic rate. It is, therefore, suggested that the energy involved in maintaining an animal in the water column is generally insignificant compared to its overall activity. Furthermory, advantages of neutral buoyancy other than energy conservation may be more important selective factors for this characteristic.
State reduction in molecular simulations

Abstract Model reduction is an important systems task with a long history in traditional chemical engineering modeling. We discuss its interplay with modern data-mining tools (such as Local Feature Analysis and Diffusion Maps) through illustrative examples, and comment on important open issues regarding applications to large systems arising in molecular/atomistic simulations.
TWO-FLUID MAGNETOHYDRODYNAMIC CYCLE FOR NUCLEAR-ELECTRIC POWER CONVERSION

To circumvent the high temperatures required in a magnetohydrodynamic power conversion system employing a plasma as the conductor, it is proposed that a liquid metal be employed as the conductor, the metal being accelerated by the vapor of a second fluid in a two-phase nozzle and extracted by a liquid-gas separator. It is estimated that a cycle efficiency of 10% is attainable at a radiator-toreactor temperature ratio of 0.7. The specific weight of such a two- fluid MHD conversion system would be about the same as that of a turboelectric system. (auth)
Myogenic Vector Expression of Insulin-like Growth Factor I Stimulates Muscle Cell Differentiation and Myofiber Hypertrophy in Transgenic Mice *

Abstract The avian skeletal α-actin gene was used as a template for construction of a myogenic expression vector that was utilized to direct expression of a human IGF-I cDNA in cultured muscle cells and in striated muscle of transgenic mice. The proximal promoter region, together with the first intron and 1.8 kilobases of 3′-noncoding flanking sequence of the avian skeletal α-actin gene directed high level expression of human insulin-like growth factor I (IGF-I) in stably transfected C2C myoblasts and transgenic mice. Expression of the actin/IGF-I hybrid gene in C2C muscle cells increased levels of myogenic basic helix-loop-helix factor and contractile protein mRNAs and enhanced myotube formation. Expression of the actin/IGF-I hybrid gene in mice elevated IGF-I concentrations in skeletal muscle 47-fold resulting in myofiber hypertrophy. IGF-I concentrations in serum and body weight were not increased by transgene expression, suggesting that the effects of transgene expression were localized. These results indicate that sustained overexpression of IGF-I in skeletal muscle elicits myofiber hypertrophy and provides the basis for manipulation of muscle physiology utilizing skeletal α-actin-based vectors.
Evaluating the role of the alpha-7 nicotinic acetylcholine receptor in the pathophysiology and treatment of schizophrenia

The group of schizophrenia disorders affects approximately 1% of the population and has both genetic and environmental etiologies. Sufferers report various behavioral abnormalities including hallucinations and delusions (positive symptoms), reduced joy and amotivation (negative symptoms), plus inattention and poor learning (cognitive deficits). Despite the heterogeneous symptoms experienced, most patients smoke. The self-medication hypothesis posits that patients smoke to alleviate symptoms, consistent with evidence for nicotine-induced enhancement of cognition. While nicotine acts on multiple nicotinic acetylcholine receptors (nAChRs), the primary target of research is often the homomeric α7 nAChR. Given genetic linkages between schizophrenia and this receptor, its association with P50 sensory gating deficits, and its reduced expression in post-mortem brains, many have attempted to develop α7 nAChR ligands for treating schizophrenia. Recent evidence that ligands can be orthosteric agonists or positive allosteric modulators (PAMs) has revitalized the hope for treatment discovery. Herein, we present evidence regarding: (1) pathophysiological alterations of α7 nAChRs that might occur in patients; (2) mechanistic evidence for the normal action of α7 nAChRs; (3) preclinical studies using α7 nAChR orthosteric agonists and type I/II PAMs; and (4) where successful translational testing has occurred for particular compounds, detailing what is still required. We report that the accumulating evidence is positive, but that greater work is required using positron emission tomography to understand current alterations in α7 nAChR expression and their relationship to symptoms. Finally, cross-species behavioral tasks should be used more regularly to determine the predictive efficacy of treatments.
Mechanism of the acute pressor action of hypokalemia, hypomagnesemia, and hypo-osmolality

Abstract The hemodynamic mechanism of the acute pressor action of hypokalemia, hypomagnesemia, and hypo-osmolality was studied in the anesthetized dog. The electrolyte changes were first produced rapidly (within 5 minutes) by a dilutional technique and then more slowly (within 50 minutes) utilizing a potent diuretic and modified Ringer's solution. Blood pressure and cardiac output were measured and total peripheral resistance was calculated. The data suggest that the blood pressure rises because of effects on the periphery when the electrolyte changes are produced rapidly by the dilutional technique and because of effects on both the heart and periphery when the electrolyte changes are produced more slowly by the diuretic technique.
Low Level Stimulation in the Differentiation of Middle Ear Pathology

A 20-db SL tone was presented at 4000, 1000 and 500 cps respectively for three minutes. Following each exposure, subjects traced threshold recovery to the stimulating tone for five minutes on a Bekesy-type automatic audiometer. Forty-six subjects with aural conductive disorders and 23 subjects with normal hearing were evaluated.On the basis of this investigation the following conclusions were considered tenable:1. Epstein and Bower's data suggesting greater Temporary Threshold Shift (TTS) over time for conductively involved ears than for normally-hearing ears were confirmed.2. Four-thousand cps produced the greatest TTS and provided the most differentiation between normal and conductive ears particularly by the fifth minute of recovery.3. The amount of TTS was positively correlated with both extent of hearing loss and duration of hearing loss regardless of the specific etiology.4. Although the Initial Temporary Threshold Shift differentiated normal ears from conductively involved ears, the measure provide...
THE PERCEPTION OF TRAVERSED DISTANCE: INTERSECTIONS

Two experiments were performed to assess the effects of intersections on distance cognition in the urban environment. A laboratory study examined estimated traversed distance as a function of the n...
Multiple cracking in CrN and Cr2N films on brass

Abstract Multiple cracking in brittle CrN and Cr2N films on a brass substrate is examined by a combination of experimental observations and finite-element modeling with the goal of better understanding the mechanics of film cracking. Films of thickness 1–6 μm, deposited by unbalanced magnetron sputtering onto brass, are fractured by uniaxially straining the brass in tension. In situ observation in the optical and scanning electron microscope provide accurate measurements of the film crack spacing as a function of strain. Finite-element modeling was conducted to show that a substantial in-plane stress gradient through the film thickness exists during the development of cracks, and that this gradient likely affects the saturation crack spacing. It is further shown through the experimental observations and associated modeling that the stress redistribution in the substrate during film cracking and the resulting stress transfer to the film affects the mechanism of cracking.
Race and Residence Variation in Living Arrangements among Unmarried Older Adults: Findings from a Sample of Floridians

This study examines race and residence differences in the likelihood of unmarried older persons living alone. Using data collected from a stratified, random sample of elderly persons conducted in both rural and urban areas of north Florida (N = 1,200), the investigation demonstrates that among the unmarried (n = 704), African Americans and residents of urban areas are more likely to live with others than are Whites and rural residents, respectively. This study also finds that the effects of race and residence on living alone are additive. Other factors found to significantly influence living arrangements are age, gender, the occurrence of a hospitalization in the past year, and the number of unmarried children. Variation in two additional aspects of the living arrangements of unmarried elders-the proximity of children and the relationship between elders and other members of the household-offer insight into the race and residence differences in living alone that remain unexplained by the multivariate analysis.
Empathy: Some implications of social cognition research for interpretation study

The purpose of this essay is to demonstrate how we might borrow from the work on social cognition to enrich our understanding of the empathic process as it relates to the performance of literature. Specifically, it surveys several conceptions of empathy in social cognition research and relates these to the various processes that interpreters have identified as empathic.
Incorporating student mobility in achievement growth modeling: A cross-classified multiple membership growth curve model

Multiple membership random effects models (MMREMs) have been developed for use in situations where individuals are members of multiple higher level organizational units. Despite their availability and the frequency with which multiple membership structures are encountered, no studies have extended the MMREM approach to hierarchical growth curve modeling (GCM). This study introduces a cross-classified multiple membership growth curve model (CCMM-GCM) for modeling, for example, academic achievement trajectories in the presence of student mobility. Real data are used to demonstrate and compare growth curve model estimates using the CCMM-GCM and a conventional GCM that ignores student mobility. Results indicate that the CCMM-GCM represents a promising option for modeling growth for multiple membership data structures.
Behavioral assumptions and theory development: the case of transaction cost economics

From a critical realist perspective, I discuss the role played by behavioral assumptions in organization theories, and use transaction cost economics as an illustrative example. Core behavioral assumptions often constitute the foundation of the mechanismic explanations of a theory, and thus should play a pivotal role in theory development. I distinguish between assumption-based and assumption-omitted theory testing, and show that empirical research in transaction cost economics has been dominated by assumption-omitted testing. To establish a solid foundation for a new theory, management researchers should pay more attention to assumption-based testing. Copyright © 2006 John Wiley & Sons, Ltd.
Serotonin transporter and MAO-B levels in monoamine nuclei of the human brainstem are normal in major depression.

Neurochemical imbalance between noradrenergic and serotonergic systems has been postulated to underlie the pathophysiology of psychiatric illnesses involving mood disorders. The present study was designed to examined the possibility that serotonergic innervation of the locus coeruleus (LC) is abnormal in major depression, by measuring two proteins expressed by serotonergic neurons, but not by noradrenergic neurons, in the region of the LC. The specific binding of [(3)H]paroxetine to serotonin transporter (SERT) and of [(3)H]lazabemide to monoamine oxidase (MAO-B) were measured autoradiographically in tissue sections cut transversely at multiple levels along the rostro-caudal extent of the LC, as well as in the caudal portion of the dorsal raphe nucleus, from psychiatrically normal subjects and age-matched subjects with major depression. Under the conditions of the assays, [(3)H]paroxetine binding in the LC was specific for the SERT, based on the rank order of affinity of compounds for inhibiting [(3)H]paroxetine binding in the LC, i.e. citalopram > imipramine > desipramine > mazindol. The binding of [(3)H]paroxetine to SERT and [(3)H]lazabemide to MAO-B were higher in the raphe nuclei than in the LC. Comparison of control subjects to major depressive subjects revealed no differences in the amount of [(3)H]paroxetine binding to SERT and [(3)H]lazabemide to MAO-B in the LC, as well as in the raphe nuclei. These findings imply that serotonergic innervation of the LC is intact in major depression.
Pheromone and host odor-stimulated potentials in Dendroctonus

Les possibilites de mouvement des muscles antennaires furent enregistres simultanement par electroantennogramme chez deux especes deDendroctonus reagissant a la pheromone et aux odeurs des plantes sur lesquelles elles vivent. Dans les deux sexes de ces especes, le potentiel moteur differa en raison de la pheromone et de l'odeur.
Surfactant-free Synthesis of Ultrasmall Gold Nanoclusters

The role of surfactant (most often tetraoctylammonium bromide) in the two-phase Brust gold nanocluster synthesis (Brust, M.; Walker, M.; Bethell, D.; Schiffrin, D. J.; Whyman, R. J. Chem. Soc., Chem. Commun. 1994, 801) has been unclear. The results of the surfactant-free synthesis of gold nanoclusters in methylene chloride employing NaBH4 as a reducing agent with the usual synthetic conditions such as excess thiol:gold ratio (>3) and ice-cold reaction temperature are reported. A nanocluster mixture, ∼5% yield with Au(I)SR byproducts, was obtained. The isolated Au nanoclusters were characterized by mass spectrometry, UV−visible, and nuclear magnetic resonance spectroscopy. MALDI-TOF mass spectrometry reveals the presence of mixtures of nanoclusters in the Au16−Au31 size range. Discrete features in the UV−visible spectrum suggested the presence of small <2 nm particles. Relatively sharp peaks in NMR confirm the small size of the nanoclusters as suggested by MALDI-TOF MS. These results are in contrast to the...
Anxiety, depression, and quality of life in primary care patients.

Background: Anxiety and depressive disorders have a significant and negative impact on quality of life. However, less is known about the effects of anxiety and depressive symptoms on quality of life. The purpose of this study was to examine the impact of anxiety and depressive symptoms on emotional and physical functioning, the effects of anxiety symptoms on functioning independent of depressive symptoms, and the effects of depressive symptoms on functioning independent of anxiety symptoms. Method: Participants included 919 patients, recruited from 2 university-affiliated primary care clinics between May 2004 and September 2006, who completed self-report measures of anxiety symptoms, depressive symptoms, and quality of life. Results: Almost 40% of the sample reported anxiety symptoms and 30% reported depressive symptoms. In both unadjusted and adjusted models, anxiety and depressive symptoms were significantly associated with all domains of quality of life. When anxiety and depressive symptoms were added simultaneously, both remained significant. As the severity of anxiety or depressive symptoms increased, quality of life decreased. Furthermore, patients with moderate to severe anxiety or depressive symptoms had greater impairments in most quality of life domains than patients with acute myocardial infarction, congestive heart failure, or diabetes. Conclusion: Detection and treatment of anxiety and depressive symptoms in the primary care setting should be emphasized.
Gene Expression of Angiogenic Factors Correlates with Metastatic Potential of Prostate Cancer Cells

We hypothesize that expression of proangiogenic genes correlates with the metastatic potential of prostate cancer cells. LNCaP, DU-145, and PC-3 are prostate cancer cell lines with low, moderate, and high metastatic potential, respectively, as we demonstrated by their capacity to invade an extracellular matrix, an established tumor invasion assay. The constitutive gene expression of the proangiogenic factors, vascular endothelial growth factor, intercellular adhesion molecule-1, interleukin-8, and transforming growth factor-β2, was significantly greater in the more metastatic DU-145 and PC-3 cells as compared with LNCaP cells. Matrix metalloproteinase (MMP)-9 is thought to contribute to the invasive phenotype of tumor cells. PC-3 cells showed increased expression of MMP-9 and membrane type 4-MMP as compared with LNCaP and DU-145. Tissue inhibitors of metalloproteinase 1 and 4 gene expression were elevated in DU-145 and PC-3 cells, but paradoxically, LNCaP cells had undetectable levels of these genes. We transfected and overexpressed MMP-9 in poorly metastatic LNCaP cells and measured their invasive activity. Transient expression of human MMP-9 in LNCaP cells produced a 3–5-fold increase in MMP-9 activity with a comparable increase in invasiveness. Antisense ablation of the expression of MMP-9 in DU-145 and PC-3 cells produced concomitant inhibition of the gene expression of the proangiogenic factors, vascular endothelial growth factor, and intercellular adhesion molecule-1 (ICAM-1). Treatment of DU-145 and PC-3 cells with a selective chemical inhibitor of MMP-9 proteinase activity also inhibited their invasive activity. These results support our hypothesis that metastatic potential of prostate cancer cells correlates with expression of proangiogenic factors.
City-Suburban, Metro-Nonmetro, and Regional Differences in the Housing Quality of U.S. Elderly Households:

This article uses data from the 1987 American Housing Survey (AHS) to assess in what U.S. locations elderly (age 60 and over) households are more at risk of occupying physically deficient housing. Metropolitan and nonmetropolitan locations are distinguished by their settlement type (city, suburban, and rural) and regional contexts. The AHS data consisted of a sample of 12,859 age 60 and older householders representing a statistical population of 26,318,348 American households. Within metropolitan areas, central cities had the highest rate of physical deficiencies whereas the urban suburbs suffered from the lowest prevalence rates. Elderly households living in nonmetropolitan rural areas, and in the rural parts of metropolitan areas, had the highest housing deficiency rates in the country. These national comparisons were misleading, however, to the extent that they primarily reflected the poor housing conditions found in only one or two regions of the country, particularly the South.
Overcoming a limitation of deterministic dense coding with a nonmaximally entangled initial state

Under two-party deterministic dense coding, Alice communicates (perfectly distinguishable) messages to Bob via a qudit from a pair of entangled qudits in pure state |{Psi}>. If |{Psi}> represents a maximally entangled state (i.e., each of its Schmidt coefficients is {radical}(1/d)), then Alice can convey to Bob one of d{sup 2} distinct messages. If |{Psi}> is not maximally entangled, then Ji et al. [Phys. Rev. A 73, 034307 (2006)] have shown that under the original deterministic dense-coding protocol, in which messages are encoded by unitary operations performed on Alice's qudit, it is impossible to encode d{sup 2}-1 messages. Encoding d{sup 2}-2 messages is possible; see, for example, the numerical studies by Mozes et al. [Phys. Rev. A 71, 012311 (2005)]. Answering a question raised by Wu et al. [Phys. Rev. A 73, 042311 (2006)], we show that when |{Psi}> is not maximally entangled, the communications limit of d{sup 2}-2 messages persists even when the requirement that Alice encode by unitary operations on her qudit is weakened to allow encoding by more general quantum operators. We then describe a dense-coding protocol that can overcome this limitation with high probability, assuming the largest Schmidt coefficient of |{Psi}> is sufficiently close to {radical}(1/d). Inmore » this protocol, d{sup 2}-2 of the messages are encoded via unitary operations on Alice's qudit, and the final (d{sup 2}-1)-th message is encoded via a non-trace-preserving quantum operation.« less
Interstitial fluid flow in tendons or ligaments: A porous medium finite element simulation

The purpose of this study is to describe interstitial fluid flow in axisymmetric soft connective tissue (ligaments or tendons) when they are loaded in tension. Soft hydrated tissue was modelled as a porous medium (using Darcy's Law), and the finite element method was used to solve the resulting equations governing fluid flow. A commercially available computer program (FiDAP) was used to create an axisymmetric model of a biomechanically tested rat ligament. The unknown variables at element nodes were pressure and velocity of the interstitial fluid (Newtonian and incompressible). The effect of variations in fluid viscosity and permeability of the solid matrix was parametrically explored. A transient loading state mimicking a rat ligament mechanical experiment was used in all simulations. The magnitude and distribution of pressure, stream lines, shear (stress) rate, vorticity and velocity showed regular patterns consistent with extension flow. Parametric changes of permeability and viscosity strongly affected fluid flow behaviour. When the radial permeability was 1000 times less than the axial permeability, shear rate and vorticity increased (approximately 5-fold). These effects (especially shear stress and pressure) suggested a strong interaction with the solid matrix. Computed levels of fluid flow suggested a possible load transduction mechanism for cells in the tissue.
Risk of low birth weight associated with advanced maternal age among four ethnic groups in the United States.

Objectives: To examine and compare the risk of low birth weight associated with delayed childbearing in four ethnic groups using nationally representative data in the United States. Methods: We compared the risk of low (<2.5 kg) birth weight among African Americans, Mexican Americans, Puerto Ricans, and non-Hispanic whites using birth data for the United States obtained from the National Center for Health Statistics. Comparisons were done separately for first births and births of second or higher order and in terms of odds ratios, risk differences and attributable fractions of very low (<1.5 kg), middle low (1.5–2.5) and overall low birth weight. Statistical analysis included use of logistic regression models with likelihood ratio tests for interaction effects. Results: African Americans and Puerto Ricans, and to a lesser extent Mexican Americans, had higher risk differences associated with advanced maternal age. For first births, the risk differences associated with advanced maternal age (≥35 years) in low birth weight were 5.3% (95% CI, 4.7–6.0), 4.3% (95% CI, 1.7–6.9), and 3.7% (95% CI, 2.8–4.5) for African Americans, Puerto Ricans, and Mexican Americans, respectively, as compared with 2.6% (95% CI, 2.4–2.7) for non-Hispanic whites. On the other hand, the odds ratios associated with advanced maternal age were more similar across the four ethnic groups. Differences were greater for all ethnic groups in the case of first births as compared with births of second or higher order. Conclusions: Advanced maternal age appears to be associated with for the most part similarly increased odds of low birth weight for African Americans, Mexican Americans, Puerto Ricans, and non-Hispanic whites. However, the age-related increments in the risk of low birth associated with advanced maternal age are greater for African Americans, Puerto Ricans and, to a lesser extent, Mexican Americans, as compared with non-Hispanic whites.
DBT for adolescents: Dialectical dilemmas and secondary treatment targets

The primary aim of this paper is to describe the central dialectical dilemmas the authors have observed in treating suicidal adolescents and their families using Dialectical Behavior Therapy (DBT). These dilemmas supplement those described by Linehan in standard DBT with adults. The adolescent/family dialectical dilemmas are excessive leniency vs. authoritarian control, normalizing pathological behaviors vs. pathologizing normative behaviors, and forcing autonomy vs. fostering dependence. We also discuss the corresponding treatment targets we have identified; these are aimed at achieving a synthesis between the polarities inherent in each dialectical dilemma.
2E-4 Dynamics of Ultrasound Contrast Agents and Microvessels with MHz-Frequency Ultrasound

Experimental studies of the dynamics of ultrasound contrast agents (UCAs) both in vitro and in vivo indicate that UCA oscillation can enhance vascular permeability and increase extravasation of drugs and genes at a target site. For improving local drug and gene delivery efficiency and minimizing any permanent damage to small blood vessels, it is essential to examine the mechanism whereby vascular permeability is enhanced and vascular injuries in small blood vessels are produced. In this work, we proposed a theoretical model to study the dynamics of the oscillation of UCAs and microvessels with MHz-frequency ultrasound (US) with emphasis on the potential application of drug and gene delivery. Numerical results demonstrate that the presence of UCAs with ultrasound can substantially increase the transmural pressure through the blood vessel and thus enhance the vascular permeability. For a microbubble within an 8 to 40-micron vessel with a low peak negative pressure such as 0.1 MPa and a center frequency of 1 MHz, small changes in the microbubble oscillation frequency and maximum diameter are observed. Strong nonlinear oscillation occurs and the induced circumferential stress in the vessel increases as the ultrasound pressure increases. For the compliable vessels considered in this work, 0.2 MPa PNP at 1 MHz is predicted to be sufficient for microbubble fragmentation. However, for a rigid vessel 0.5 MPa PNP at 1 MHz may not be sufficient to fragment the bubbles. For a center frequency of 1 MHz, a peak negative pressure of 0.5 MPa is predicted to be sufficient to induce the stress in the vessel which exceeds the vascular rupture limit in a small (diameter less than 15 mum) compliant vessel. As vasculature becomes more rigid, the UCA oscillation and vessel dilation decrease, however the circumferential stress is predicted to increase. The circumferential stress in the vessel increases as the vessel size decreases or the center frequency increases. For the two frequencies considered in this work, the circumferential stress does not scale as the inverse of the square root of the acoustic frequency va in the Mechanical Index, but rather has a stronger frequency dependence, 1/va