cssi/SciSciGPT-SciSciNet huggingface dataset:
Time use satisfaction of wives: Home, farm, and labor force workload

Factors related to time spent in work roles are investigated for a sample of 685 wives living on family farms in seven southern and midwestern states. Data were collected in a comprehensive mail survey. Results show that variables reflecting management are the most important predictors of wife's time use satisfaction. Wife's satisfaction is also significantly related to her education and nonfarm employment. Conclusions indicate that, although wives on family farms experience work-role overload relative to their husbands, they are satisfied with their time contributions to the home/farm situation.
Reactions of Titanocene Derivatives with Molecular Carboxylic Acids and Copolymers Bearing Carboxylic Acid Groups

Linear, soluble copolymers containing titanium are of interest for use in targets for inertial-confinement fusion (ICF) experiments because the titanium is a useful spectroscopic probe for studying the nuclear fusion process. We have studied the reactions of dichloro- titanocene and diphenyltitanocene with carboxylic acids to determine if these can be used to prepare such polymers. Model reactions of dichlorotitanocene with p-toluic acid show that both mono- and di-carboxylates are formed. We have prepared a soluble titanium-containing copolymer via the reaction of poly(styrene-co-methacrylic acid) with an excess of dichlorotitanocene but attempts to remove the excess molecular titanocene from the copolymer result in crosslinking of the copolymer. Model reactions of benzoic and pivalic acids with diphenyltitanocene demonstrate that monosubstituted carboxylato(phenyl)titanocenes are formed but that these products are stable only at low temperatures and decompose readily at ambient temperature. Proton NMR studies of the reaction of diphenyltitanocene and benzoic acid at −20 °C indicate that this reaction is second order, suggesting that the reaction does not proceed through a benzyne intermediate. © 1997 by John Wiley & Sons, Ltd.
The Children’s Depression Inventory in Worldwide Child Development Research: A Reliability Generalization Study

Childhood depression is a serious mental problem and has detrimental effects on child development. The Children’s Depression Inventory (CDI) has been commonly used to measure childhood depression in developmental research across the world. The present study aimed at meta-analyzing estimates of Cronbach’s alpha reported in previous studies and identifying study characteristics that affect score reliability. The final sample included 331 alphas obtained from 114,023 children in 283 primary studies conducted in 44 countries and areas by using 25 different languages. Although alphas reported in the literature were generally high with a point estimate of .840, 95 % CI [.834, .846], considerable heterogeneity existed between studies. The long form of CDI with 27 items had higher alphas than the short form with 10 items. Sample size and group heterogeneity were correlated with alpha. Moreover, alphas did not differ across linguistic forms of the CDI, indicating the cross-cultural equivalence of score reliability. Implications for future applied and methodological research were discussed.
Brain lesions modifying the abstinence signs in morphine-dependent rats

Abstract Abstinence signs, mastication (teeth chattering), myoclonic twitch and repetitive shaking movements (wet shakes) were precipitated by naloxone and were recorded electromyographically from the suprahyoideal muscle in morphine-dependent rats anaesthetized with urethane. Transverse brain lesions were made bilaterally with an iridectomy knife in urethane anaesthetized morphine-dependent rats. Lesions at the level of the anterior commissure did not inhibit the myoclonic twitch and mastication but markedly potentiated wet shakes. Lesions which separated the connection between the corpus striatum and the thalamus completely abolished mastication, but the twitching activity and wet shakes were not affected. Mid-thalamus lesions did not inhibit wet shakes and mastication, but the myoclonic twitch activity was markedly reduced. Lesions at the mid-collicular level abolished all of the three activities observed. The results suggest that different precipitated withdrawal signs may originate from different brain areas.
Analytical steady-state solution to the rapid buffering approximation near an open Ca2+ channel

We derive an analytical steady-state solution for the Ca2+ profile near an open Ca2+ channel based on a transport equation which describes the buffered diffusion of Ca2+ in the presence of rapid stationary and mobile Ca2+ buffers (Wagner and Keizer, 1994). This steady-state rapid buffering approximation gives an upper bound on local Ca2+ elevations such as Ca2+ puffs or sparks when conditions for the validity of the rapid buffering approximation are met and is an alternative to approximations that assume that mobile buffers are unsaturable. This result also provides an analytical estimate of the cytosolic Ca2+ domain concentration ([Ca2+]d) near a channel pore and shows the dependence of [Ca2+]d on moderate concentrations of endogenous mobile buffer, Ca2+ indicator dye, and bulk cytosolic Ca2+. Assuming a simple relationship between [Ca2+]d and the lumenal depletion domain of an intracellular Ca2+ channel, lumenal and cytosolic Ca2+ profiles are matched to give an implicit analytical expression for the effect of bulk lumenal Ca2+ on [Ca2+]d.
Polarization-dependent photoyield for evaporated Na films

The polarization dependence of photoemission from vapor-quenched and annealed sodium films recently observed is confirmed using samples prepared in a different manner. A temperature variation in the polarization dependence is observed. The results are consistent with a surface-photoemission yield about twice the bulk value near threshold.
Defining the Roles of Various Lysines and Arginines in Amot Lipid Binding

One of the defining traits of cancerous cells is proliferation. We are focusing on the proliferation of mammary cells. As an adaptor protein, the Amot membrane binding event is key to the localization and sorting of proteins responsible for cellular differentiation, proliferation, and migration. The Amot coiled-coil homology domain (ACCH) is a lipid-binding domain responsible for affinity and binding to endothelial membranes. Our working hypothesis is that the ability to modulate Amot lipid-binding will lead to means to prevent ductal cell hyperplasia progression into breast cancer tumors. We will determine which residues are responsible for lipid-binding by changing positively charged lysine and arginine into uncharged or negatively charged amino acids. Those mutations which show a significant decrease in lipid-binding will then be used to determine their down-stream effects in human cells. The laboratory has screened approximately 40 of these mutations using a liposome binding assay. This assay mimics how the protein binds with the cell membrane by using an in vitro mixture of lipids similar to that seen in endothelial cells. Forster resonance energy transfer (FRET) was used to confirm significant decreases in lipid binding of ACCH mutants selected from the liposome binding assay, as energy transfer only occurs when the tyrosines in the protein and the Dansylated liposome are in close proximity to each other. Based on these two screens we have narrowed the list to seven mutants that have a significant decrease in lipid binding. Currently, FRET is being used to determine the lipid binding coefficient for each mutant of interest. Mutants deemed important from this study will then be transformed into human cells to study their effects on cell polarity, signal transduction, cell shape, and cellular proliferation.
Phosphonacetyl-L-aspartate: an aspartate transcarbamylase inhibitor causing larval death and rudimentary wing phenocopies in Drosophila melanogaster.

Phosphonacetyl-L-aspartate, an inhibitor and transition state analogue of aspartate transcarbamylase, has been found to cause rudimentary wing phenocopies and larval death in Drosophila melanogaster. We believe this compound may prove useful as a selection agent for regulatory mutations at the rudimentary locus.
A new friction factor correlation for laminar, single-phase flows through rock fractures

Single-phase flow through fractured media occurs in various situations, such as transport of dissolved contaminants through geological strata, sequestration of carbon dioxide in depleted gas reservoirs, and in primary oil recovery. In the present study, fluid flows through a rock fracture were simulated. The fracture geometry was obtained from the CT scans of a rock fracture produced by the Brazilian method in a sandstone sample. A post-processing code using a CAD package was developed and used to generate the three-dimensional fracture from the CT scan data. Several sections along the fracture were considered and the Gambit™ code was used to generate unstructured grids for flow simulations. FLUENT™ was used to analyze the flow conditions through the fracture section for different flow rates. Because of the small aperture of the fractures, the gravitational effects could be neglected. It was confirmed that the pressure drop was dominated by the smallest aperture passages of the fracture. The accuracy of parallel plate models for estimating the pressure drops through fractures was studied. It was shown that the parallel plate flow model with the use of an appropriate effective fracture aperture and inclusion of the tortuosity factor could provide reasonable estimates for pressure drops in the fracture. On the basis of the CFD simulation data, a new expression for the friction factor for flows through fractures was developed. The new model predictions were compared with the simulation results and favorable agreement was found. It was shown that when the length of the fracture and the mean and standard deviation of the fracture are known, the pressure loss as a function of the flow rate could be estimated. These findings may prove useful for design of lab experiments, computational studied of flows through real rock fractures, or inclusions in simulators for large-scale flows in highly fractured rocks.
Positively selecting peptides: their job does not end in the thymus

Peptides able to positively select major histocompatibility complex class II–restricted thymocytes have not yet been defined. Two new reports identify and ascribe important extrathymic functions to several positively selecting peptides for CD4+ T cells.
Human cortical representations for reaching: mirror neurons for execution, observation, and imagery

Abstract We used functional magnetic resonance imaging (fMRI) to map the cortical representations of executed reaching, observed reaching, and imagined reaching in humans. Whereas previous studies have mostly examined hand actions related to grasping, hand–object interactions, or local finger movements, here we were interested in reaching only (i.e. the transport phase of the hand to a particular location in space), without grasping. We hypothesized that mirror neuron areas specific to reaching-related representations would be active in all three conditions. An overlap between executed, observed, and imagined reaching activations was found in dorsal premotor cortex as well as in the superior parietal lobe and the intraparietal sulcus, in accord with our hypothesis. Activations for observed reaching were more dorsal than activations typically reported in the literature for observation of hand–object interactions (grasping). Our results suggest that the mirror neuron system is specific to the type of hand action performed, and that these fronto-parietal activations are a putative human homologue of the neural circuits underlying reaching in macaques. The parietal activations reported here for executed, imagined, and observed reaching are also consistent with previous functional imaging studies on planned reaching and delayed pointing movements, and extend the proposed localization of human reach-related brain areas to observation as well as imagery of reaching.
E.s.r. study of the post-radiolysis growth of spin-trapped radicals in gamma-irradiated aqueous solutions of thymine.

The post-irradiation growth of the spin-adduct nitroxide radical produced by the addition of the thymine--OD radical to t-nitrosobutane (tNB) in gamma-irradiated, de-aerated D2O solutions was investigated by e.s.r. The thymine--OD radical was formed by the addition of an OD radical to the C(5) position of thymine. Growth reached a greater maximum value and was more rapid with increasing dose. At a fixed dose, growth was also greater and more rapid if oxygen was present after gamma-radiolysis. The addition of a second radical to the spin-adduct nitroxide during radiolysis to give a diamagnetic intermediate, which can regenerate the spin-adduct radical during storage in air-free and in air-saturated solutions at room temperature, was inferred to be responsible for post-irradiation growth. U.V. photolysis at 260-280 nm of a solution containing the diamagnetic intermediate rapidly regenerates the spin-adduct nitroxide. The longer lifetime of the diamagnetic intermediate in oxygen-free solutions may be relevant to an understanding of the anoxic sensitization by nitroxides in cellular systems.
Development of a transabdominal anchoring system for trocar-less laparoscopic surgery

Compared with open surgery, laparoscopy results in significantly less pain, faster convalescence, and less morbidity. However, eye-hand dissociation, a two-dimensional field-of-view and fixed instrumentation with limited degrees of freedom contribute to a steep learning curve and demanding dexterity requirements for many laparoscopic procedures. One of the main limitations of laparoscopy is the fixed working envelope surrounding each trocar, often necessitating placement of multiple ports to accomodate changes in position of the instruments or laparoscope to improve visibility and efficiency. The placement of additional working ports contributes to post-operative pain and carries a small risk of bleeding or adjacent organ damage. In order to provide for greater flexibility of endoscopic viewing and instrument usage and to further reduce morbidity, a novel adjunct laparoscopic system has been developed consisting of a platform capable of supporting various laparoscopic tools which is secured magnetically to the abdominal wall and subsequently positioned within the abdominal cavity through surgeon-controlled, external magnetic couples on the patient’s abdomen. Using this technique, instruments such as miniature endoscopic cameras used to augment the surgical field of view and surgical retractors have been successfully evaluated in a dry laboratory as well as in porcine models, with several others currently under investigation. This document elaborates on the theoretical and empirical process which has led to anchoring designs optimized for size, strength and surgical compatibility, as well as the benefits, limitations and prospects for the use of incisionless, magnetically-coupled tooling in laparoscopic surgery.Copyright © 2003 by ASME
Exocytosis from a single rat chromaffin cell by cholinergic and peptidergic neurotransmitters

Abstract Secretion of catecholamines from chromaffin cells is mediated by cholinergic and peptidergic neurotransmitters. 3,11,14 The cholinergic transmitter acetylcholine activates both nicotinic and muscarinic receptors to trigger catecholamine secretion in rat adrenal medulla. 17 Vasoactive intestinal polypeptide (VIP) has been identified as the peptidergic transmitter in rat adrenal medulla and may also be the non-cholinergic transmitter in bovine adrenal. 18,23 Pituitary adenylate cyclase activating polypeptide (PACAP), a VIP-like secretin peptide, is also found in the adrenal, 5 and is a potent secretagogue. 7,21 Thus, PACAP may be another peptidergic transmitter at the adrenal synapse. 19 A most intriguing property of rat chromaffin cells is that stimulation of nicotinic, muscarinic, VIP or PACAP receptors are each able to produce robust catecholamine secretion on their own. 11–13,21 This raises the question of whether a single chromaffin cell can respond to each of the above agonists or whether the secretion is due to subpopulations of chromaffin cells. This issue was addressed by using electrochemical techniques to monitor exocytosis from individual chromaffin cells in culture. 2,9,22 We demonstrate that acetylcholine, nicotine, muscarine, VIP and PACAP are each able to evoke catecholamine secretion from a single chromaffin cell. Some cells only responded to acetylcholine. Furthermore, each agonist produced a distinct pattern of exocytosis. Muscarine-evoked secretion exhibited a latency of 0.5–2 s, but exocytosis persisted up to 30 s following 500ms stimulation. Nicotine produced an immediate response which usually ended within 10s. The secretory pattern following acetylcholine appeared to be the sum of the nicotinic and muscarinic patterns, showing both rapid onset and longer duration. The unique property of peptidergic stimulation was that a brief exposure caused exocytosis to persist for up to 2 min. Like muscarine, peptides exhibited latency in producing exocytosis. These findings support the idea that the interactive control of catecholamine secretion by nicotinic, muscarinic and peptidergic receptors occurs at the level of single cells.
Study of the characterization and curing of Benzoxazines using 13C solid-state nuclear magnetic resonance

Benzoxazines derived from bisphenol-A, formaldehyde, and primary amines were characterized using 13 C solid-state NMR spectroscopy. The two 1,3- benzoxazines studied in this work are 2,2! -(3-methyl-4-dihydro-1,3,2-benzoxazine)pro- pane, (B-m) and 2,2! -(3-phenyl-4-dihydro-1,3,2-benzoxazine)propane (B-a). Solid-state 13 C-NMR spectra were obtained for B-m and B-a and the observed peak positions were noted. These resonances agreed well with chemical shifts calculated based on the chemical structure. Samples of B-m and B-a were cured at two different temperatures: 150 and 200°C. The polymerizations induced spectral changes including new reso- nances, intensity changes, and line-width broadenings. Kinetic analysis of the curing data gave different kinetic parameters for the two cure temperatures, which is expected since the first cure temperature is below the material's glass transition temperature (Tg) while the second cure temperature is above the Tg. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 1413-1425, 1998
Launching CROMA: Computational Research On Music & Audio

This lightning talk describes the current effort to create a research group at Lincoln University to conduct Computational Research On Music & Audio (CROMA). A CROMA Team of Interdisciplinary Collaborators (CROMA-TIC) will be assembled to participate in different aspects and applications of computational audio signal processing, drawing from disciplines such as computer science, mathematics, music, psychology, and nursing. This effort is modelled upon the Centre for Interdisciplinary Research in Music Media and Technology (CIRMMT) housed at McGill University, but it will be distinct in its focus on undergraduate research. Further, this research group will be unique among Historically Black Colleges and Universities (HBCUs). A goal of assembling CROMA-TIC and establishing the CROMA-Lab is to inspire participants, especially including minority students, to seek graduate degrees while enriching their undergraduate learning experiences. The initial research aims will focus on sound event separation within musical audio, with the idea that the research conducted by CROMA-TIC will be applicable to a wide array of applications (such as improving the performance of hearing aids in noisy environments or automatic transcription of music recordings, among innumerable possibilities). This effort is just underway; interested faculty and students are invited to attend the presentation and consider participation in CROMA so that it may develop into a truly interdisciplinary, multi-institutional endeavour.
Can you have your meat and eat it too? Conscientious omnivores, vegetarians, and adherence to diet

As criticisms of factory farming continue to mount, an increasing number of individuals have changed their existing dietary practices. Perhaps the two most important food movements reacting against industrial farming are (1) vegetarianism, the avoidance of animal flesh; and (2) conscientious omnivorism (CO), the consumption of meat or fish only when it satisfies certain ethical standards. While the former group has been well-studied in the social science literature, there have been few, if any, studies specifically examining those who identify themselves as ethical meat eaters. The present research sought to determine if one particular diet was more greatly adhered to by its followers. Results revealed that COs were less likely to perceive their diet as something that they absolutely needed to follow, reported violating their diet more, felt less guilty when doing so, believed less in animal rights, were less disgusted by factory-farmed meat, rated its sensory characteristics more favorably, and were lower in ingroup identification than vegetarians. Mediation analysis demonstrated that differences in the amount of violations and guilt associated with these violations could in part be traced to practical and psychological factors, making it more difficult to follow conscientious omnivorism.
Antidepressant effects of nicotine in an animal model of depression.

Epidemiological studies indicate a high incidence of cigarette smoking among depressed individuals. Moreover, individuals with a history of depression have a much harder time giving up smoking. It has been postulated that smoking may reflect an attempt at self-medication with nicotine by these individuals. Although some animal and human studies suggest that nicotine may act as an antidepressant, further verification of this hypothesis and involvement of nicotinic cholinergic system in depressive symptoms is required. Flinders Sensitive Line (FSL) rats have been proposed as an animal model of depression. These rats, selectively bred for their hyperresponsiveness to cholinergic stimulation, show an exaggerated immobility in the forced swim test compared to their control Flinders Resistant Line (FRL) rats. Acute or chronic (14 days) administration of nicotine (0.4 mg/kg s.c.) significantly improved the performance of the FSL but not the FRL rats in the swim test. The effects of nicotine on swim test were dissociable from its effects on locomotor activity. Moreover, the FSL rats had significantly higher [3H]cytisine binding (selective for the alpha4beta2 nicotinic receptor subtype) but not [125I]alpha-bungarotoxin binding (selective for the alpha7 subtype) in the frontal cortex, striatum, midbrain and colliculi compared to FRL rats. These data strongly implicate the involvement of central nicotinic receptors in the depressive characteristics of the FSL rats, and suggest that nicotinic agonists may have therapeutic benefits in depressive disorders.
Effects of the self-administration of ethanol and ethanol/sucrose on rates of local cerebral glucose utilization in rats

In a previous study, the voluntary ingestion of ethanol by rats was found to be associated with a discrete pattern of changes in functional activity that included the nucleus accumbens, medial prefrontal cortex, basolateral and central nuclei of the amygdala, as well as the ventral midbrain. Rats in this study, however, consumed a combination of ethanol in a sucrose vehicle. The purpose of the present experiment was to characterize the role of sucrose in determining the effects of orally self-administered ethanol using the quantitative autoradiographic 2-[14C]deoxyglucose (2DG) method for measurement of rates of local cerebral glucose utilization. A modified sucrose-substitution procedure was employed to train three groups of Wistar rats to self-administer either water, 10% ethanol (10E), or a 10% ethanol/2% sucrose solution (10E/2S) in daily sessions. An additional group of rats was trained using a modified acclimation procedure (home cage) in order to determine if any exposure to sucrose would alter rates of glucose utilization. Once stable rates of consumption were established, the 2DG method was applied immediately following completion of the final test session. Rats received a dose of ethanol equivalent to 0.5 g kg-1 on the day of the procedure or a comparable volume of water. Rates of energy metabolism were significantly increased in all three groups of rats that consumed ethanol (10E/2S, 10E, and home cage), as compared to rates in rats that consumed water. The areas of significant change included the rostral pole and posterior shell of the nucleus accumbens, medial prefrontal cortex, the basolateral and central nuclei of the amygdala, the ventral tegmental area, and the substantia nigra pars compacta. Thus, the pattern of changes in functional brain activity that accompanies voluntary ingestion of ethanol is independent of the vehicle in which the ethanol is presented or the procedures used to initiate consumption. Furthermore, these data demonstrate that it is the simultaneous activation of an interrelated network of limbic brain regions that serves as the substrate of the effects of ethanol self-administration.
Calcium dynamics in cultured heart cells exposed to defibrillator-type electric shocks.

Abstract Spatial and temporal changes in intracellular calcium ion concentration and transmembrane voltage were recorded optically from single-isolated cultured chick-embryo heart cells exposed to high-voltage, defibrillator-type shocks. Fluorescence changes were measured during 5 msec electric shocks of field strengths up to 56 volts cm in single myocytes stained with a Ca++-sensitive or voltage-sensitive dye. Shocks caused a reversible period of depolarization, elevated cytosolic Ca++, and refractoriness. Intracellular Ca++ elevation had two temporal phases: first, a Ca++ spike with morphology independent of shock intensity; and second, a prolonged Ca++ elevation with a shock-intensity-dependent magnitude and duration, and with greatest Ca++ elevation at the poles of the cell adjacent to the electrodes. The prolonged elevation (second phase) was initiated earlier at the anode-facing pole of the cell than at the cathode-facing pole. These results suggest that postshock Ca++ entry consists of two parts: early normal entry through excitation channels plus a prolonged elevation which may be related to cellular damage.
The performance of de novo commercial banks: A profit efficiency approach

Abstract We examine the profit efficiency of US banks chartered between 1980 and 1994. Our results suggest that profit efficiency improves rapidly at the typical de novo bank during its first three years of operation, but on average takes about nine years to reach established bank levels. Excess branch capacity, reliance on large deposits, and affiliation with a multibank holding company are associated with low profit efficiency at de novo banks. De novo national banks are initially less profit efficient than are state-chartered de novos, perhaps reflecting differences in the chartering philosophy of federal and state bank regulators.
Interpersonal relations in four-year dyads from constructivist and montessori programs☆

Abstract Forty 4-year-old children from Constructivist and Montessori preschool programs were compared on social-cognitive competence. The Experimenter (E) taught children in pairs to play a board game in Session 1, and in Session 2 asked them to play the game by themselves. Analysis of video and transcripts of 2208 behavioral units using Selman's coding of interpersonal negotiation strategies showed that Montessori pairs used a significantly higher proportion of strategies at Level 1, and Constructivist pairs used a significantly higher proportion of strategies at Level 2. Less conflict was found in Constructivist pairs, and they resolved their conflicts significantly more frequently. Within conflict segments, Montessori children had a significantly higher proportion of Level 0 strategies, and Constructivist pairs had a significantly higher proportion of Level 2 strategies. Both groups followed some basic rules equally well, but Constructivist pairs followed other rules more consistently. Although no difference was found in general ability to count dots on the die, Constructivist children on the whole counted spaces on the board more accurately. It was concluded that children from the Constructivist program were more advanced in social-cognitive competence than children from the Montessori program.
Viscothermoelasticity with finite wave speeds: thermomechanical laws

The development of constitutive equations of linear viscothermoelasticity, free of the paradox of infinitely fast propagation of heat, is in the focus of this work. Two models from hyperbolic thermoelasticity—theory with one relaxation time and theory with two relaxation times—provide the stepping-stone. The setting for these models is offered, respectively, by the primitive thermodynamics of Edelen and the thermodynamic orthogonality of Ziegler, in both cases involving internal parameters. The telegraph-like heat conduction is governed in the first case by the Maxwell–Cattaneo model and in the second by the Fourier law. In the first case, temperature and its first derivative appear in the thermomechanical constitutive relation, whereas in the second case also the second derivative is present.
Efficient fixed-point realization of approximate dynamic inversion compensators for non-minimum phase systems

This paper considers a fixed-point realization of approximate stable inversion of systems with non-minimum phase zeros. It is based on the efficient linear phase IIR filter implementation first introduced by Powell and Chau. The proposed filter is used in inversion based feedforward tracking and repetitive controllers which is realized by a Field Programmable Gate Array to control a piezoelectric actuator and generate precise dynamic high bandwidth motion at a 100 kHZ sampling rate.
Contributions to the History of Psychology: CXV. In Search of Loyal Crane: A Note

According to Donald Peterson in 1997, Loyal Crane was the first to propose the Doctor of Psychology degree. Despite an extensive search, Peterson did not uncover any additional information on Crane. We believe we have been able to identify him.
Engaging Diverse Gifted Learners in U.S. History Classrooms

The strengths and talents of diverse gifted learners must be supported in culturally responsive middle and high school classrooms. Secondary social studies teachers can use teaching strategies to provide an enriched experience in U.S. history classrooms that will engage and intellectually challenge diverse gifted learners. The model proposed by Ford and Harris (1999) for delivering multicultural gifted education offers educators a framework for delivering culturally responsive curriculum.
ROLE OF DIFFUSION IN COLLECTIVE LEARNING

The critical nature of diffusion in understanding the link between individual competency and collective competency is often underconceptualized. Organizational learning involves diffusion of knowledge and/or skill from the individual to members of the collective, and expansion of the collective's capacity to take effective action. Three types of individual and collective competency are identified, ranging on a continuum from explicit‐and‐quickly‐diffused to tacit‐and‐slowly‐diffused Patterns of diffusion can occur in stages: by critical mass, in cycles, or in a synthesis of styles. A model illustrating these dynamics is presented. Criteria for evaluating successful collective learning are introduced.
Vitamin D resistance and alopecia: a kindred with normal 1,25-dihydroxyvitamin D binding, but decreased receptor affinity for deoxyribonucleic acid.

A new kindred exhibiting vitamin D resistance and alopecia is described. Clinically, three of seven sisters demonstrated rickets, hypocalcemia, elevated serum 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] levels, and alopecia. Biochemical analysis of cultured fibroblasts from skin biopsy explants in two affected and one normal sister revealed normal [3H]1,25-(OH)2D3 binding to receptors (Kd = 0.05 nM; Nmax = 30-50 fmol⁄ mg protein). Despite normal steroid binding, cells from the two affected sisters failed to respond to 1,25-(OH)2D3 in vitro, as measured by induction of the enzyme 25-hydroxyvitamin D-24- hydroxylase. The cells from the normal sister showed a response within the range of five normal cell lines. Sucrose gradient analysis yielded a typical 3.2S protein under high salt conditions in extracts from the three siblings, but with reduced capacity to aggregate to a 6S moiety in low salt gradients in the two affected cells. Whole cell [3H]1,25-(OH)2D3 binding studies revealed nearly normal localization of...
Regulation of PKR by HCV IRES RNA: Importance of Domain II and NS5A

Protein kinase R (PKR) is an essential component of the innate immune response. In the presence of double-stranded RNA (dsRNA), PKR is autophosphorylated, which enables it to phosphorylate its substrate, eukaryotic initiation factor 2alpha, leading to translation cessation. Typical activators of PKR are long dsRNAs produced during viral infection, although certain other RNAs can also activate. A recent study indicated that full-length internal ribosome entry site (IRES), present in the 5'-untranslated region of hepatitis C virus (HCV) RNA, inhibits PKR, while another showed that it activates. We show here that both activation and inhibition by full-length IRES are possible. The HCV IRES has a complex secondary structure comprising four domains. While it has been demonstrated that domains III-IV activate PKR, we report here that domain II of the IRES also potently activates. Structure mapping and mutational analysis of domain II indicate that while the double-stranded regions of the RNA are important for activation, loop regions contribute as well. Structural comparison reveals that domain II has multiple, non-Watson-Crick features that mimic A-form dsRNA. The canonical and noncanonical features of domain II cumulate to a total of approximately 33 unbranched base pairs, the minimum length of dsRNA required for PKR activation. These results provide further insight into the structural basis of PKR activation by a diverse array of RNA structural motifs that deviate from the long helical stretches found in traditional PKR activators. Activation of PKR by domain II of the HCV IRES has implications for the innate immune response when the other domains of the IRES may be inaccessible. We also study the ability of the HCV nonstructural protein 5A (NS5A) to bind various domains of the IRES and alter activation. A model is presented for how domain II of the IRES and NS5A operate to control host and viral translation during HCV infection.
Connections and frequency representation in the auditory brainstem of the mustache bat, Pteronotus parnellii

The goals of this study were to describe the cochlear frequency map of the mustache bat, Pteronotus parnellii, and to relate the organization of cochlear primary afferents to that of the second-order projections from the cochlear nucleus to the superior olivary complex. Small deposits of horseradish peroxidase (HRP) were placed in the cochlear nucleus at sites that were physiologically characterized with respect to unit-best frequency. From the deposits, labeled fibers were traced in the retrograde direction to the cochlea and in the anterograde direction to the superior olive. Cochleas from both experimental and control animals were examined with light and electron microscopy. The peripheral axons of spiral ganglion neurons were counted in order to quantify the unusual variation in the innervation density along the cochlear spiral of the mustache bat. Regions of increased innervation density were found at the beginning and end of the basal turn of the cochlea. The highest cochlear innervation density consistently occurred in the upper basal turn. In horseradish peroxidase tracing experiments, this region contained labeled fibers only when HRP deposits were made at sites within the cochlear nucleus with unit-best frequencies around 60 kHz. These findings support the suggestion (Kossl and Vater, '85) that the cochlear sites of increased innervation density are related to the neural and behavioral emphasis that this echolocating bat places upon the analysis of the 60 kHz frequency band. The general arrangement of tonotopic maps within the cochlea, cochlear nucleus, and superior olive was consistent with previous observations in this bat and other mammalian species. At all three levels, there was evidence of a disproportionately large representation of frequencies around 60 kHz, similar to the enlarged representation reported within the inferior colliculus and auditory cortex of the mustache bat. In all cases there was a consistent relation between the size of the HRP deposit and the number and distribution of retrogradely labeled neurons in the cochlea. For most cases there was a similar relation between the size of the deposit and the terminal arborization field of anterogradely labeled fibers in the superior olive. However, in cases with deposits associated with the 60 kHz frequency band, the size of the labeled arborization field was more than twice as large as expected from the size of the deposits and from the extent of labeling in the cochlea. These cases suggest that the representation of frequencies around 60 kHz, already overrepresented in both the cochlea and cochlear nucleus, may be further expanded at the level of the superior olivary complex.
Standing waves in optical positive photoresist films: a new approach

A new approach to the problem of standing waves in a thin positive photoresist film is given. Explicit analytic expressions are obtained in terms of the classical WKB approximation. A self-contained, convergent iteration scheme is offered for accurate determination of the fields and the concentration of the photoactive compound as functions of depth and time.
Double-Polymer-Modified Pencil Lead for Stripping Voltammetry of Perchlorate in Drinking Water

The inexpensive and disposable electrode based on a double-polymer-modified pencil lead is proposed for upper-division undergraduate instrumental laboratories to enable the highly sensitive detection of perchlorate. Students fabricate and utilize their own electrodes in the 3–4 h laboratory session to learn important concepts and methods of electrochemistry. The simple electrodes allow for the detection of perchlorate in tap water at concentrations below an interim health advisory level of 15 ppb (∼150 nM) set by the U.S. Environmental Protection Agency. Specifically, a pencil lead is first modified with a conducting poly(3-octylthiophene) (POT) membrane through electropolymerization by cyclic voltammetry, followed by the dip coating of a plasticized poly(vinyl chloride) (PVC) membrane. The PVC/POT-modified electrode is operated in the stripping voltammetric mode to give a linear current response to 100–1000 nM perchlorate in tap water. This high sensitivity is due to the thermodynamically favorable preco...
Bias reduction for risk ratio and vaccine effect estimators

We examine the structural bias for established estimators of vaccine effects on susceptibility and for newer estimates of vaccine effects on infectiousness. We then propose and analyse new bias corrections for vaccine effect estimators of both susceptibility and infectiousness, as well as their combined effect on infection transmission. Each estimator is evaluated empirically with computer simulations. Of the estimators examined in this paper, those with the least bias and root mean squared error are computed by adding one to the positive count in the placebo population. We also identify a source of bias for a standard Bayesian estimator of risk ratios.
Bounded arithmetic for NC, ALogTIME, L and NL

Abstract We define theories of bounded arithmetic, whose definable functions and relations are exactly those in certain complexity classes. Based on a recursion-theoretic characterization of NC in Clote (1988, 1990), the first-order theory TNC, whose principal axiom scheme is a form of short induction on notation for nondeterministic polynomial-time computable relations, has the property that those functions having nondeterministic polynomial-time graph Θ(x, y) such that TNC ⊢∀x ∃y Θ(x, y) are exactly the functions in NC, computable on a parallel random-access machine in polylogarithmic parallel time with a polynomial number of processors.0 We then define three theories of weak second-order arithmetic which respectively characterize relations in the classes of alternating logarithmic time, logspace and nondeterministic logspace.
The NHLBI Clinical Trials Network in transfusion medicine and hemostasis: an overview.

Transfusion Medicine is a broad discipline that affects the health care of patients from many medical disciplines. Despite the large impact of transfusion therapies on the management of patients with a variety of diseases, there are few clinical trials that evaluate the indications or the effectiveness of transfusion therapies. To respond to this need for better clinical data, the National Heart Lung and Blood Institute of the National Institutes of Health established a clinical trials network in Transfusion Medicine and Hemostasis. Following a competitive selection process, 17 university medical centers and a data coordinating center joined together to collaboratively address clinical questions in transfusion medicine and hemostasis. The activities, organization, and scope of the network is described below. Examples of clinical trials currently in the network “pipeline” are briefly summarized as an overview to more detailed presentations given elsewhere in this symposium. J. Clin. Apheresis 2006. 21:57–59, © 2006 Wiley-Liss, Inc.
Improved impregnation technique for the preservation of stone statuary.

ATMOSPHERIC attack on stone statuary has increased considerably during the past few decades because of the presence of increasing amounts of gaseous pollutants such as SO2 and CO2 (ref. 1). There are two types of technique2 for the preservation of stone: those which provide, by means of impregnation, both a protective coating and a cement between dislodged grains; and those which change the chemistry of the stone so that the resultant substance is more resistant to attack.
Parallel program schemata

This paper introduces a model called the parallel program schema for the representation and study of programs containing parallel sequencing. The model is related to Ianov's program schema, but extends it, both by modelling memory structure in more detail and by admitting parallel computation. The emphasis is on decision procedures, both for traditional properties, such as equivalence, and for new properties particular to parallel computation, such as determinacy and boundedness.
Epidemiologic Approaches to Global Health

In this introduction to volume 32 of "Epidemiologic Reviews", the authors highlight the diversity and complexity of global health concerns, and they frame the 12 articles included in this issue within the diverse topics of research in this emerging and ever-expanding field. The authors emphasize the need for ongoing research related to the methods used in global health research.
Distinct genomic signatures of adaptation in pre- and postnatal environments during human evolution

The human genome evolution project seeks to reveal the genetic underpinnings of key phenotypic features that are distinctive of humans, such as a greatly enlarged cerebral cortex, slow development, and long life spans. This project has focused predominantly on genotypic changes during the 6-million-year descent from the last common ancestor (LCA) of humans and chimpanzees. Here, we argue that adaptive genotypic changes during earlier periods of evolutionary history also helped shape the distinctive human phenotype. Using comparative genome sequence data from 10 vertebrate species, we find a signature of human ancestry-specific adaptive evolution in 1,240 genes during their descent from the LCA with rodents. We also find that the signature of adaptive evolution is significantly different for highly expressed genes in human fetal and adult-stage tissues. Functional annotation clustering shows that on the ape stem lineage, an especially evident adaptively evolved biological pathway contains genes that function in mitochondria, are crucially involved in aerobic energy production, and are highly expressed in two energy-demanding tissues, heart and brain. Also, on this ape stem lineage, there was adaptive evolution among genes associated with human autoimmune and aging-related diseases. During more recent human descent, the adaptively evolving, highly expressed genes in fetal brain are involved in mediating neuronal connectivity. Comparing adaptively evolving genes from pre- and postnatal-stage tissues suggests that different selective pressures act on the development vs. the maintenance of the human phenotype.
Data grid and gridflow management systems

The 'Grid' is an emerging infrastructure providing coordinated and consistent services to access distributed, heterogeneous computational and information storage resources amongst autonomous organizations. Data grids are being built across the world as the next generation inter-organizational data management systems for coordinated sharing of data as well as storage resources. A data grid is a location independent logical namespace consisting persistent global identifiers for digital entities, storage resources and users in an autonomous inter-organizational collaboration. Data Grid Management Systems (DGMS) provide services on the data grid?s logical name space for management and organization of digital entities and resources. These data-intensive environments involve long run processes, which could be aggregated as Grid Workflows (Gridflows). Gridflows are executed as peer-to-peer workflows in the data grid infrastructure by the Gridflow Management Systems. The tutorial will introduce the grid, provide use-cases in large projects, examine requirements, introduce some possible solutions for managing data in the grid and using a services-oriented infrastructure. It will take real-world examples from current systems, in particular the Storage Resource Broker and the SDSC Matrix project.
Bioavailability of zinc in several sources of zinc oxide, zinc sulfate, and zinc metal.

Three zinc depletion-repletion assays were carried out with chicks to determine Zn bioavailability in five sources of ZnO, three sources of ZnSO4.H2O, and two sources of Zn metal. A standard 23% CP corn-soybean meal diet was fed during the first 3 d posthatching, after which it was replaced with a Zn-deficient soy concentrate diet (13.5 mg Zn/kg) until d 7. On d 8 after an overnight period of feed withdrawal, chicks were fed for 12 d the Zn-deficient basal diet containing 0, 4.76, and 9.90 (Assay 1); 0, 5.06, or 10.12 (Assay 2); or 0, 4.73, or 9.13 (Assay 3) mg/kg supplemental Zn from analytical grade (AG) ZnSO4.7H2O (22.7% Zn) to generate a standard response curve. The AG and feed-grade (FG) Zn sources being evaluated were then provided at a level that would fall within the standard curve. Weight gain (Assays 1, 2, and 3) and total tibia Zn (Assay 1) responded linearly (P .10) from the standard, but average RBV values for FG Source 2 and FG Source 3 were only 34 (P .10) in RBV from the ZnSO4.7H2O standard. Two Zn metal products, Zn metal dust (100% Zn) and Zn metal fume (91.5% Zn), were also evaluated, and they were found to have Zn RBV values of 67 (P<.05) and 36% (P<.05), respectively. Feed-grade sources of ZnO vary widely in color, texture, Zn content, and Zn bioavailability.