cssi/SciSciGPT-SciSciNet huggingface dataset:
Permeability for flow of interdendritic liquid in columnar-dendritic alloys

Permeability data for the flow of interdendritic liquid in partially solid Pb−Sn and borneol-paraffin columnar-alloys are summarized. The data are used in regression analyses and simple flow models to arrive at relationships between permeability and the morphology of the solid dendrites. When flow is parallel to the primary dendrite arms, the important morphological aspects are the volume fraction liquid (g L) and the primary dendrite arm spacing (d 1). When flow is normal to the primary dendrite arms, the permeability depends upon the secondary dendrite arm spacing (d 2) as well asd 1 andg L. The parallel permeability is best described by a model based on the Hagen-Poiseuille law for laminar flow through a tube; for the normal permeability an empirical multilinear regression gives the best fit to the data. However, those models are not appropriate for extrapolations beyond the range of the available data (0.19≤g L≤0.66), particularly asg L approaches 1. For extrapolations, models based upon the Blake-Kozeny equation for flow through porous media are recommended.
Morphology and sintering of Pt crystallites on amorphous SiO2

Abstract Effects of O2, N2, H2O, and Cl2 atmospheres on sintering rates and morphologies of Pt on amorphous SiO2 were studied by observation with transmission electron microscopy following heat treatment in flowing gases at 1 atm. An initial Pt film 10 to 20 A thick produced crystallites 10 to 200 A in diameter when heated to 400 to 700 °C. The average crystallite size was larger by a factor of up to 2 in air than in N2, and H2O in these gases significantly inhibited particle growth. No crystallite migration was observed in any gases at any temperature. Atomic diffusion is therefore the exclusive sintering mechanism even though the size distribution exhibited a “tail” on the large diameter side which had been predicted by the particle coalescence model. Oxygen enhancement could occur through vapor transport as PtO2 or through surface diffusion, although it is suggested that the latter is more plausible. Tilt experiments showed that all particles were three dimensional. Bright- and dark-field microscopy revealed that at least 20% of the particles heated to 600 °C exhibited twinning, and multiple twins were observed in at least 2% of the particles. Good correspondence is observed between these results and behavior of supported catalysts.
A preliminary numerical study of solitary wave propagation in a disordered medium

Abstract In this paper we present a preliminary numerical study of the propagation of a soliton in a weakly disordered potential consisting of a number of randomly placed spatially localized scatterers. By conducting the experiment in the locally stationary frame of the soliton we are able to follow the soliton through a large number of scattering events, thus obtaining very good information on the long-distance propagation properties of a soliton in such a medium. The observed behavior is in agreement with the theoretical predictions of Kivshar et al. [Phys. Rev. Lett. 64 (15) (1990) 1693] and Bronski [J. Nonlinear Sci. (1996)]. For solitons whose incident mass is relatively small compared with their velocity (the nearly linear regime) we observe numerically an exponential decay in the mass of the soliton, while the mass of the soliton approaches a constant after a large number of scattering events. When the ratio of the incident soliton mass to the incident soliton velocity is sufficiently large, however, a very different behavior is observed. The mass of the solitary wave is observed to asymptotically approach a constant, while the velocity decays slowly to zero, as predicted by the theory. For suffiviently small velocities (when the theory is no longer valid) we observe phenomena of total reflection and trapping.
The Economics of Early Childhood Education in Minnesota

This is a case study of the “installation” of economic education at the kindergarten-primary grades in one state. The author points out that the effectiveness of this process depends on the demand for such instruction, the materials available, the willingness and capabilities of teachers, and the time allocated for such instruction. Success in installing economic education at this level is likely to depend on school goals and their evaluation.
Debate: On Christiano's The Constitution of Equality

WHEN a principle like democracy becomes as widely accepted as it is today, the philosophical defensibility of a democratic stance becomes more interesting. It also becomes pressing because more views and actions are defended on the ground that they are part of democracy, or an implication of democracy, or required by democracy, or authorized by democracy. If the principle of democracy (or, more accurately, the principle that democracy, or only democracy, is authoritative, or legitimate, or justified, etc.) cannot be cogently defended then this set of views is a house of cards. Eventually, the winds will come and the cards will fall. Democracy is and always has been a vulnerable doctrine, which is not to say it isn’t correct. But it had better not be assumed to be correct. The objections need to be faced and answered. One of the most important objections is the charge that because the great masses of citizens are ignorant, or irrational, or immoral, or all three, political decisions would best be made by a more competent subset of people. Tom Christiano, in his recent book, The Constitution of Equality: Democratic Authority and Its Limits, provides, among other things, a deeply considered and philosophically original answer to this historically important (and always current) charge against democracy. In this short essay, I accept the journal’s invitation to discuss Christiano’s theory, and respond to his own essay in which he discusses the theory I develop in my recent book, Democratic Authority: A Philosophical Framework. While this is what the occasion calls for, it can’t produce more than the most partial appreciation of the ingenuity and depth of Christiano’s book. I begin with a sketch of what I understand to be at the structural core of Christiano’s theory. (Christiano gives a helpful sketch of my view in his piece, so I forgo doing much of that here.) It is a political theory, but it is anchored in general moral principles. At the foundation of morality, Christiano argues, is the principle that everyone’s well-being is important, and equally so. Moral agents are required to recognize and honor this importance of the well-being of others, and also to do
Dimethacrylate network formation and polymer property evolution as determined by the selection of monomers and curing conditions.

Objectives This overview is intended to highlight connections between monomer structure and the development of highly crosslinked photopolymer networks including the conversion dependent properties of shrinkage, modulus and stress.
Technology diffusion and firm performance: It pays to join the digital bandwagon!

Abstract This article examines the relationship between the deployment of technology and subsequent productivity in major firms in local telecommunication exchanges in the United States over the period 1995–2000. Technological progress is measured by the extent to which digital technology spread within the firms’ networks. Using a set of performance measures that decomposes company profitability into productivity and price-recovery measures, we found that deployed digital network technology has a positive and significant impact on firms’ productivity but a negative impact on firms’ price-recovery patterns. We conclude that it is beneficial for firms to join the digital era sooner rather than later.
Proposed methods for improving the efficiency of the DMFS index in assessing initiation and progression of dental caries

Recent changes in the epidemiology of dental caries and advances in the development of new diagnostic measurement techniques have stimulated interest in improved methods of assessing changes in dental caries status. Traditional methods for assessing change focus primarily on the development of new lesions at the cavitation level and incorporate incomplete information on the progression of existing cavitated lesions. A methodology to expand the clinical recording of dental caries in clinical studies to include 1) both non-cavitated and cavitated lesions and 2) the surface area affected for restorations is suggested. New indices are proposed to estimate changes in the number of new lesions, the progression of existing carious lesions, and the total change in caries status for a subject. It is anticipated that the new indices will produce more efficient methods of assessing change in caries status in longitudinal clinical studies. The degree of improvement can be estimated directly. Improvements in efficiency may reduce the duration or number of subjects required in caries clinical trials.
The cAMP-Dependent Protein Kinase A and Protein Kinase C-β Pathways Synergistically Interact to Activate HIV-1 Transcription in Latently Infected Cells of Monocyte/Macrophage Lineage

Abstract The HIV-1 long terminal repeat (LTR) responds to a variety of cellular signal transduction pathways. We demonstrate that the cAMP-dependent protein kinase A (PKA) and protein kinase C (PKC) signaling pathways synergize to increase HIV-1 LTR-mediated transcription and viral replication in a latently infected promonocytic cell line (U1). The LTR-mediated synergy induced by cholera toxin (Ctx), a potent activator of the cAMP-dependent PKA pathway, and the PKC activator phorbol 12-myristate 13-acetate (PMA) was abrogated by a PKC-β-specific inhibitor (LY333531). In contrast, the LTR-mediated synergy induced by Ctx and TNFα was not affected by LY333531. The synergy induced by Ctx and TNFα was also abrogated by mutation of the cAMP-responsive downstream sequence elements (DSE) in the 5′ untranslated leader region, whereas the DSE mutations did not affect the synergy induced by Ctx and PMA. These distinctions indicate that Ctx cooperates differently with TNFα and PMA to activate the HIV-1 LTR. Ctx and PMA synergistically activated AP-1- and NF-κB-dependent transcription, even though no cooperative binding of AP-1 or NF-κB was observed in gel shift assays. An extensive mutational analysis of the HIV-1 LTR that included the NF-κB and AP-1 binding sites revealed no distinct cis -acting element or region within the HIV-1 LTR that was required for the transcriptional synergy. Ctx and PMA also synergistically interact to activate the HTLV-1 LTR. These results indicate that the transcriptional synergy elicited by Ctx and PMA targets multiple functional elements and promoters, requires a cooperative interaction between the PKA and PKC-β pathways, and differs mechanistically from the transcriptional synergy induced by Ctx and TNFα.
Energy correlations in electron-positron annihilation in quantum chromodynamics: Asymptotically free perturbation theory

In the absence of infrared mass singularities, the asymptotic behavior of cross sections for ${e}^{+}{e}^{\ensuremath{-}}$ annihilation in quantum chromodynamics can be expressed entirely in terms of the energy dependence of the renormalization-group running coupling constant. Since the theory is asymptotically free, the running coupling vanishes at high energy, and such infrared-finite cross sections can be calculated perturbatively. We extend previous work by calculating, through second order, the energy-weighted angular correlations of the hadrons produced in ${e}^{+}{e}^{\ensuremath{-}}$ annihilation. This involves the computation of quark-antiquark-gluon production and the correction to the lowest-order quark-antiquark production from virtual gluon exchange. A dimensional-continuation scheme is employed to establish that these correlations, taken in a distribution-theory sense, are indeed free of mass singularities. The correlations exhibit interesting features which vanish slowly ($\ensuremath{\propto}\frac{1}{\mathrm{ln}W}$) as the energy $W$ increases. We estimate that the nonperturbative, confinement contributions to these features vanish much more rapidly ($\ensuremath{\propto}\frac{1}{{W}^{2}}$). Thus, effects characteristic of quantum chromodynamics should be quite evident at high energies.
Orthostatic hypotension: a commonly unrecognized cause of symptoms in mitral valve prolapse

To test the hypothesis that orthostatic hypotension could represent an alternative mechanism contributing to the symptoms of mitral valve prolapse, the systolic and diastolic arterial blood pressures were measured in the supine and standing positions in 86 patients with the diagnosis confirmed by echocardiography. Orthostatic hypotension was demonstrated in 12 patients. Ten of them presented with a history of recurrent lightheadedness, dizziness or syncope and constitute 59 percent of the total number of patients with such symptoms in this series. Although nine of these 10 patients reported transient lightheadedness or dizziness during periods of ambulatory electrocardiographic recording, in only one were the symptoms chronologically related to cardiac arrhythmias. On the other hand, eight of them described lightheadedness and two experienced near-syncope during the postural test in association with the orthostatic drop in blood pressure. Improvement in symptoms and correction of the orthostatic hypotension were demonstrated in seven patients after beta-adrenergic blockade with propranolol. Before therapy, the mean systolic blood pressure dropped from 114 +/- 3 mm Hg in the supine position to 78 +/- 1 mm Hg upon standing (p less than 0.001). In repeated postural tests performed after four weeks of treatment, the systolic blood pressure changed from 120 +/- 3 mm Hg supine to 115 +/- 1 mm Hg upon standing (p greater than 0.01). We conclude that orthostatic hypotension is a commonly unrecognized mechanism responsible for some of the symptoms of mitral valve prolapse, particularly in patients affected by recurrent lightheadedness, dizziness or syncope.
Yields of fission products produced by thermal-neutron fission of 243Cm.

On the basis of measured yields for 72 gamma rays and known nuclear data, cumulative fission-product yields were deduced for 69 fission products having half-lives between 36 seconds and 65 days representing 41 mass chains created during thermal-neutron fission of $^{243}\mathrm{Cm}$.
Glucocorticoids Inhibit the Transcriptional Activity of LEF/TCF in Differentiating Osteoblasts in a Glycogen Synthase Kinase-3β-dependent and -independent Manner

Glucocorticoids, widely used as immune suppressors, cause osteoporosis by inhibiting bone formation. In MC3T3-E1 osteoblast-like cultures, dexamethasone (DEX) activates glycogen synthase kinase-3beta (GSK3beta) and inhibits a differentiation-related cell cycle that occurs at a commitment stage immediately after confluence. Here we show that DEX inhibition of the differentiation-related cell cycle is associated with a decrease in beta-catenin levels and inhibition of LEF/TCF-mediated transcription. These inhibitory activities are no longer observed in the presence of lithium, a GSK3beta inhibitor. DEX decreased the serum-responsive phosphorylation of protein kinase B/Akt-Ser(473) within minutes, and this inhibition was also observed after 12 h. When the phosphatidylinositol 3-kinase (PI3K)/Akt pathway was inhibited by wortmannin, DEX no longer inhibited beta-catenin levels. Furthermore, DEX-mediated inhibition of LEF/TCF transcriptional activity was attenuated in the presence of dominant negative forms of either PI3K or protein kinase B/Akt. These results suggest cross-talk between the PI3K/Akt and Wnt signaling pathways. Consistent with a role for Wnt signaling in the osteoblast differentiation-related cell cycle, wortmannin partially negated the DEX inhibition of this cell cycle. DEX also induced histone deacetylase (HDAC) 1, which is known to inhibit LEF/TCF transcriptional activity. Overexpression of HDAC1 negated the inhibitory effect of DEX on LEF/TCF transcriptional activity. In the presence of trichostatin A, a deacetylase inhibitor, DEX-mediated inhibition of the differentiation-related cell cycle was partially negated. When administered together, wortmannin and trichostatin A completely negated the inhibitory effect of DEX on the differentiation-related cell cycle. These results suggest that inhibition of a PI3K/Akt/GSK3beta/beta-catenin/LEF axis and stimulation of HDAC1 cooperate to mediate the inhibitory effect of DEX on Wnt signaling and the osteoblast differentiation-related cell cycle.
FULLY RELATIVISTIC TREATMENT OF THE BREHMSTRAHLUNG RADIATION FROM A CHARGE FALLING IN A STRONG GRAVITATIONAL FIELD.

Abstract The details of the spectral distribution of the radiation emitted by a particle freely falling in a gravitational field are given in the case of the most general static asymptotically flat solution with regular horizon. No contradiction exists with the principle of equivalence. A clear enhancement of high multipoles is shown to exist.
High-Temperature Desulfurization of Gasifier Effluents with Rare Earth and Rare Earth/Transition Metal Oxides

We have improved the application of mixed rare-earth oxides (REOs) as hot gas desulfurization adsorbents by impregnating them on stable high surface area supports and by the inclusion of certain transition metal oxides. We report comparative desulfurization experiments at high temperature (900 K) using a synthetic biomass gasifier effluent containing 0.1 vol % H2S, along with H2, CO2, and water. More complex REO sorbents outperform the simpler CeO2/La2O3 mixtures, in some cases significantly. Supporting REOs on Al2O3 (~20 wt % REO) or ZrO2 actually increased the sulfur capacities found after several cycles on a total weight basis. Another major increase in sulfur capacity took place when MnOx or FeOx is incorporated. Apparently most of the Mn or Fe is dispersed on or near the surface of the mixed REOs because the capacities with REOs greatly exceeded those of Al2O3-supported MnOx or FeOx alone at these conditions. In contrast, incorporating Cu has little effect on sulfur adsorption capacities. Both the REO and transition metal/REO adsorbents could be regenerated completely using air for at least five repetitive cycles.
Clinical, immunologic, and genetic features of familial systemic sclerosis

Objective To examine whether the affected first-degree relatives within multicase systemic sclerosis (SSc; scleroderma) families are concordant for autoantibody profile, disease type, and HLA class II haplotypes and whether clinical expression and serologic characteristics of familial SSc differ from those of sporadic SSc. Methods Seven hundred ten SSc families from the Scleroderma Family Registry and DNA Repository (Scleroderma Registry) were examined, and 18 multicase families were identified. SSc cases and their first-degree family members underwent serologic testing for different autoantibodies. The disease type and various disease features were abstracted from the available medical records. Additionally, HLA class II typing was performed on the multicase SSc sibpairs. Results The observed SSc-specific antibody concordance within each multicase SSc family was statistically more common than expected by chance alone (P = 0.007). The autoantibody profile and disease features of familial and sporadic SSc cases did not differ significantly. The frequency of autoantibody positivity was not different between unaffected first-degree family members of patients from multicase versus singleton SSc families. HLA haplotype sharing between SSc sibpairs was significantly more common than expected (P = 0.011). Conclusion The affected members within multicase SSc families tend to be concordant for SSc-specific autoantibodies and HLA haplotypes; familial SSc does not appear to be a unique disease subset.
Laparoendoscopic single-site and natural orifice surgery in gynecology

Objective To evaluate the current literature on the use of single port and natural orifice surgery in gynecology. Design Appraisal of articles published on the use of this technology in gynecology. Result(s) Most reports on single port and natural orifice surgery are case reports or case series. However, most have reported successful outcomes such as diagnostic or extirpative gynecologic procedures. The main limitation is the availability of instrumentation to successfully accomplish the task. Conclusion(s) Single port and natural orifice surgery offers the potential for advancing the minimally invasive approach to gynecologic surgery.
Prototypes, exemplars, and the natural history of categorization

The article explores—from a utility/adaptation perspective—the role of prototype and exemplar processes in categorization. The author surveys important category tasks within the categorization literature from the perspective of the optimality of applying prototype and exemplar processes. Formal simulations reveal that organisms will often (not always!) receive more useful signals about category belongingness if they average their exemplar experience into a prototype and use this as the comparative standard for categorization. This survey then provides the theoretical context for considering the evolution of cognitive systems for categorization. In the article’s final sections, the author reviews recent research on the performance of nonhuman primates and humans in the tasks analyzed in the article. Diverse species share operating principles, default commitments, and processing weaknesses in categorization. From these commonalities, it may be possible to infer some properties of the categorization ecology these species generally experienced during cognitive evolution.
The Alzheimer's Family Caregiver as Decision Maker: A Typology of Decision Styles

This study developed a typology of decision styles and discussed its usefulness for providing support to family caregivers of people with Alzheimer's disease. During semistructured interviews, 28 caregivers described making a total of 159 caregiving decisions. The analysis involved the classification of the caregivers' experiences into categories and the formation of a typology of the styles used throughout the decision-making process. Predecision styles include proactive, reactive, and inactive and are based on caregivers' tendencies to prepare for and initiate the decision. Postdecision styles include forecasting, attempting, and depending and are based on the caregivers'implementation plans. Although many (46.4%) of the caregivers tended toward a particular decision style, the majority were not consistent. Eight of the ten categories of decisions made appeared to require a particular decision style. Decision-making needs based on caregiving decision styles are presented to guide the provision of decisi...
Thermal lens spectrometry using a broadly tunable optical parametric oscillator.

We present a computerized optical parametric oscillator that is capable of continuous tuning from approximately 420 nm to 2 μm for spectroscopic and spectrometric applications. This system allows any selected wavelength within the tuning range to be reached directly and quickly. We demonstrate the versatility of the system by measuring the entire visible (450–690-nm) thermal lens spectrum of NO2 with a continuous scan.
Simple effective Lagrangian for hard thermal loops

We derive an alternative effective Lagrangian for the hard thermal loops between gluons in QCD at high temperature or chemical potential. This effective Lagrangian is elementary in form and manifestly gauge invariant.
Shared medical appointments for the preoperative consultation visit of Mohs micrographic surgery.

Background Shared medical appointments (SMAs) allow patients with similar diagnoses to be simultaneously educated and cared for by 1 provider. SMAs appear well suited for Mohs micrographic surgery because all patients receive similar information about skin cancer pathophysiology, prognosis, prevention, treatment, reconstructive options, and wound care. Objective We sought to create a SMA for the preoperative consultation visit of Mohs micrographic surgery and to evaluate patient satisfaction with this model. Methods A pilot SMA was implemented. Patient satisfaction was assessed via a 13-question survey over a 6-month period. Results In all, 149 patients were seen in our SMAs. The survey response rate was 65.8%. Respondents answered Likert scale questions with a mean value of 4.29 ± 0.09 (on a 1-5 scale, where 5 is the best). Patients found the SMA model useful (84.7%) and would attend another SMA in the future (80.6%). Limitations Limitations include the sample size of the study, relatively homogenous patient population, possible response bias, and a potential selection bias (as all participants in the SMA chose this type of appointment rather than a conventional one). Conclusions SMA can be successfully used for the Mohs preoperative consultation visit with high patient satisfaction.
Hierarchical Unbiased Graph Shrinkage (HUGS): A Novel Groupwise Registration for Large Data Set

Normalizing all images in a large data set into a common space is a key step in many clinical and research studies, e.g., for brain development, maturation, and aging. Recently, groupwise registration has been developed for simultaneous alignment of all images without selecting a particular image as template, thus potentially avoiding bias in the registration. However, most conventional groupwise registration methods do not explore the data distribution during the image registration. Thus, their performance could be affected by large inter-subject variations in the data set under registration. To solve this potential issue, we propose to use a graph to model the distribution of all image data sitting on the image manifold, with each node representing an image and each edge representing the geodesic pathway between two nodes (or images). Then, the procedure of warping all images to their population center turns to the dynamic shrinking of the graph nodes along their graph edges until all graph nodes become close to each other. Thus, the topology of image distribution on the image manifold is always preserved during the groupwise registration. More importantly, by modeling the distribution of all images via a graph, we can potentially reduce registration error since every time each image is warped only according to its nearby images with similar structures in the graph. We have evaluated our proposed groupwise registration method on both infant and adult data sets, by also comparing with the conventional group-mean based registration and the ABSORB methods. All experimental results show that our proposed method can achieve better performance in terms of registration accuracy and robustness.
The b-type cytochromes of bovine heart mitochondria: Absorption spectra, enzymatic properties, and distribution in the electron transfer complexes

1. 1. Three b-type cytochromes (b557.5, b560, and b562.5), plus a chromophore with an absorption peak at 558 nm at 77 °K, have been found to be associated with the electron transport system of bovine heart mitochondria. The reduced minus oxidized spectra of these components at 77 °K, as well as that of cytochrome c1, have been recorded with a wavelength accuracy of ± 0.1 nm and presented to the nearest 0.5 nm. All the major α and β absorption peaks of cytochromes b557.5, b560, b562.5, c1 and c have been shown by fourth derivative analysis to be present in the dithionite-reduced minus oxidized spectra of mitochondria and submitochondrial particles. 2. 2. The distribution of the above components has been studied in the four electron transfer complexes of the respiratory chain. Cytochromes b560, b562.5 and c1, as well as chromophore-558, were found to fractionate into Complex III (reduced ubiquinone-cytochrome c reductase), whereas cytochrome b557.5 was found in Complex II (succinate-ubiquinone reductase). 3. 3. Cytochrome b560 was readily reduced by NADH or succinate, but b562.5 was not reduced by substrates unless the preparation was treated with antimycin A. In antimycin-treated preparations pre-reduction of c1 with ascorbate inhibited the subsequent reduction of b562.5 by substrates. These results indicate that b560 and b562.5 correspond, respectively, to bK and bT previously described by Chance et al.14 (1970, Proc. Natl. Acad. Sci. U.S. 66, 1175–1182). 4. 4. Similar to b560, chromophore-558 can be reduced by substrates in the absence or presence of antimycin A. However, in antimycin-treated preparations, pre-reduction of c1 inhibits its subsequent reduction by substrates. This property is similar to that of b562.5. 5. 5. Cytochrome b557.5, which occurs in Complex II, appears to have a low mid-point potential. It can be reduced with dithionite and oxidized by fumarate or ubiquinone. CO treatment of dithionite-reduced b557.5 neither modified the spectrum of this cytochrome nor diminished the extent of b557.5 reoxidation by fumarate. 6. 6. Antimycin A treatment does not appear to alter the spectra of the above cytochromes. However, small amounts (< 4%) of ethanol or methanol, which are usually added to particles as solvent for antimycin A, have a pronounced effect on the α peaks of cytochrome c1. The spectrum of cytochrome c1 at 77 °K as modified by 3% (v/v) ethanol is shown.
Canine prostate induces new bone formation in mouse calvaria: A model of osteoinduction by prostate tissue.

BACKGROUND Osteoblastic metastases are common in patients with advanced prostate cancer. The pathophysiology of the new bone formation at metastatic sites is not currently known, but it is hypothesized that growth factors secreted by the prostate may be involved. Unfortunately, most rodent models of prostate cancer with metastasis to bone are osteolytic and not osteoblastic. Significant osteolysis by tumor cells at metastatic sites may also lead to fractures or bone instability. Misinterpretation of new periosteal bone due to bone instability as tumor-cell osteoinduction is another disadvantage of the osteolytic models. To circumvent these problems, we have developed a model system of new bone formation in the calvaria of nude mice stimulated by normal canine prostate tissue. METHODS Collagenase-digested normal prostate tissue was implanted adjacent to the calvaria of nude mice. Calvaria were examined at 2 weeks post-implantation for changes in the bone microenvironment by histology, calcein uptake at sites of bone mineralization, and tartrate-resistant acid phosphatase staining for osteoclasts. RESULTS The prostate tissue remained viable and induced abundant new woven bone formation on the adjacent periosteal surface. In some cases new bone formation also was induced on the distant or concave calvarial periosteum. The new bone stained intensely with calcein, which demonstrated mineralization of the bone matrix. The new bone formation on prostate-implanted calvaria significantly increased (1.7-fold) the thickness of the calvaria compared with control calvaria. New bone formation was not induced in calvaria of mice implanted with normal canine kidney, urinary bladder, spleen, or skeletal muscle tissue, or mice with surgically-induced disruption of the periosteum. Osteoclast numbers in the medullary spaces and periosteum of calvaria were mildly increased (61%) in mice with implanted prostate tissue. CONCLUSIONS This animal model will be useful for investigating the roles of prostate-derived growth factors on new bone formation in vivo. Prostate 50: 104–111, 2002. © 2002 Wiley-Liss, Inc.
Differences in mitochondrial 16S ribosomal gene sequences allow discrimination among American [Crassostrea virginica (Gmelin)] and Asian [C. gigas (Thunberg) C. ariakensis Wakiya] oyster species

Abstract Limited field trials for potentially disease resistant Asian cupped oysters were recently initiated in the central Atlantic coastal region of North America. We have developed a simple and sensitive genetic assay that unambiguously distinguishes the native Crassostrea virginica (Gmelin) from two of its exotic Asian congeners, C. gigas (Thunberg) and C. ariakensis (Wakiya). Homologous fragments (443 nt) of the mitochondrial rRNA large subunit were amplified from, and sequenced for, these three commercially important species of oysters. C. virginica exhibits 85.5 and 84% sequence similarity to C. gigas and C. ariakensis (respectively) and contains seven additional nucleotides in the amplified 16S gene fragment. The two Asian species do not differ in gene length and display 95.1% sequence similarity. Numerous endonuclease restriction site differences are apparent among the three oyster species and we present a polymerase chain reaction/restriction fragment length polymorphism strategy that can distinguish these species. This methodology will prove valuable in monitoring the ecological consequences, at all life history stages, of trial introductions of Asian Crassostrea species into this region.
Customer-Firm Relationships, Involvement, and Customer Satisfaction

Relationships among levels of involvement between customers and suppliers, customers' evaluations of core and peripheral factors in their transactions, and customers' overall satisfaction were exam...
Seismic hazard assessment using the theory of records

This article is a review of some basic results for analysis of records. First, the general methods appropriate for seismic hazard are discussed. Then, in view of the frequency-magnitude law of Gutenberg and Richter, some results relevant for hazard assessment related to earthquakes are presented. The discussion is concluded with an example of application and comparison with classical methods.
Challenges Facing the Semantic Web and Social Software as Communication Technology Agents in E-Learning Environments

The semantic web describes the process whereby information content is made available for machine consumption. With increased reliance on information communication technologies, the semantic web promises effective and efficient information acquisition and dissemination of products and services in the global economy, in particular, e-learning. Despite the semantic web's promises, certain challenges face the realization of these goals. In this paper, the author addresses key challenges, including technological and socio-cultural issues, in addition to discussing specific implications relating to the direction of the semantic web.
Natural history of anterior cruciate tears

An evaluation of 361 patients with documented anterior cru ciate tears was carried out with analysis of mechanisms, symp tomatology, physical findings, and limitations. At the time of injury, patients generally heard a loud pop and felt their knee "slide apart" with a subsequent hemarthrosis. Internal tibial rotation was described as the principal mechanism of injury in 81.6% of the patients. Less than 20% had a triad type injury. A "crossover" test enabled reproduction of the mechanism. On a 100 point scale, those with "no repair" scored a mean of 55.4, direct repairs 56.7, pes transfers 59.6, and modified MacIntosh 88.9 points. The natural course of a patient can often be projected. A continuing comparative study of results from treatment regimens and procedures is indicated.
dc SQUID: Noise and optimization

A computer model is described for the dc SQUID in which the two Josephson junctions are nonhysteretic, resistively shunted tunnel junctions. In the absence of noise, current-voltage(I–V) characteristics are obtained as functions of the applied flux, Φ a , SQUID inductanceL, junction critical currentI 0 , and shunt resistanceR. The effects of asymmetry inL, I 0 , andR are discussed.I–V characteristics, flux-voltage transfer functions, and low-frequency spectral densities of the voltage noise are obtained at experimentally interesting values of the parameters in the presence of Johnson noise in the resistive shunts. The transfer functions and voltage spectral densities are used to calculate the flux and energy resolution of the SQUID operated as an open-loop, small-signal amplifier. The resolution of the SQUID with ac flux modulation is discussed. The flux resolution calculated for the SQUID of Clarke, Goubau, and Ketchen is1.6 × 10 −5 Φ 0 Hz−1/2 , approximately one-half the experimental value. Optimization of the SQUID resolution is discussed: It is shown that the optimum operating condition is β=2LI 0 /Φ 0 ≈1. Finally, some speculations are made on the ultimate performance of the tunnel junction dc SQUID. When the dominant noise source is Johnson noise in the resistive shunts, the energy resolution per Hz is4k B T(πLC) 1/2 , whereC is the junction capacitance, and the constraintR=(Φ 0 /2πCI 0 ) 1/2 has been imposed. This result implies that the energy resolution is proportional to (junction area) 1/2 . In the limiteI 0 R ≫k B T, the dominant noise source is shot noise in the junctions; for β=1, the energy resolution per Hz is then approximatelyh/2.
Maximum-likelihood approach to strain imaging using ultrasound

A maximum-likelihood (ML) strategy for strain estimation is presented as a framework for designing and evaluating bioelasticity imaging systems. Concepts from continuum mechanics, signal analysis, and acoustic scattering are combined to develop a mathematical model of the ultrasonic waveforms used to form strain images. The model includes three-dimensional (3-D) object motion described by affine transformations, Rayleigh scattering from random media, and 3-D system response functions. The likelihood function for these waveforms is derived to express the Fisher information matrix and variance bounds for displacement and strain estimation. The ML estimator is a generalized cross correlator for pre- and post-compression echo waveforms that is realized by waveform warping and filtering prior to cross correlation and peak detection. Experiments involving soft tissuelike media show the ML estimator approaches the Cramer–Rao error bound for small scaling deformations: at 5 MHz and 1.2% compression, the predicted lower bound for displacement errors is 4.4 μm and the measured standard deviation is 5.7 μm.
The durability of endovascular treatment of multisegment iliac occlusive disease

Abstract Purpose: The effectiveness of endovascular treatment of multisegment iliac occlusive disease (involving two or more common and/or external iliac arteries) was determined. Methods: All patients who underwent angioplasty or stenting of at least two separate iliac artery segments were identified. Demographic data were recorded. Technical success, hemodynamic success, and aortoiliac primary and primary-assisted patency were analyzed by using the Society for Vascular Surgery and International Society for Cardiovascular Surgery (SVS/ISCVS) criteria. Multivariate, life table analysis was used as a means of determining outcome predictors. Results: Eighty-seven patients underwent 207 iliac artery angioplasties and 115 iliac artery stents, which were performed in 210 iliac segments for disabling claudication in 60% of cases, for rest pain in 17% of cases, and for tissue loss in 23% of cases. Two iliac segments were treated in 64% of patients, three segments were treated in 28% of patients, and four segments were treated in 8% of patients. The complication rate was 11%. Initial hemodynamic success was achieved in 72% of cases. Clinical improvement occurred in 88% of patients. Subsequent endovascular reintervention was required in 29% of patients, whereas surgical inflow procedures were required in 14% of patients to maintain aortoiliac patency. The mean time from the primary intervention to the first reintervention was 10 ± 3 months. At 6, 12, and 36 months after intervention, the primary patency rates of the aortoiliac segment were 76%, 61%, and 43%, respectively, and the primary assisted patency rates were 95%, 87%, and 72%, respectively. Only the presence of an external iliac artery stenosis adversely affected both primary and assisted-primary patency. At 6, 12, and 36 months, the aortoiliac primary patency rates in patients without the presence of an external iliac artery stenosis were 88%, 78%, and 69%, respectively, compared with 68%, 47%, and 18%, respectively, in patients with external iliac artery lesions ( P Conclusion: Endovascular therapy for multisegment aortoiliac occlusive disease has acceptable patency rates; however, reintervention is often needed. The presence of external iliac artery disease is a significant predictor of poor outcome. (J Vasc Surg 2000;31:1178-84.)
Major depressive disorder among older African Americans, Caribbean blacks, and non-Hispanic whites: secondary analysis of the National Survey of American Life.

Background Previous epidemiological and clinical research on mental disorders has treated Blacks as a homogenous group and yet Blacks of Caribbean descent and African Americans differ with respect to ethnicity, national heritage, living circumstances, and immigration status. The purpose of this article is to examine the prevalence of major depressive disorder (MDD) among African Americans, Caribbean Blacks, and non-Hispanic whites aged 50 and older with data on psychiatric and physical comorbidity, mental illness severity, and service use. Methods Secondary analysis of data from the National Survey of American Life, a national household probability sample of African Americans, Caribbean Blacks, and non-Hispanic Whites in the United States, were used (n = 1,950). The response rate was 72.3%. Results Controlling for age, the lifetime prevalence rate of MDD was 12.1% and the 12-month rate was 5.2%. Older Whites and Caribbean Blacks had significantly higher lifetime prevalence than African Americans but 12-month rates were similar across the three groups. Rates of co-occurring psychiatric disorders and physical conditions were high and were similar for African Americans, Caribbean Blacks, and Whites. Most older adults had either moderate or severe 12-month MDD and most talked to at least one professional, most frequently a family doctor, psychiatrist, or other mental health professional. Conclusion MDD among older adults is highly prevalent, often associated with other psychiatric disorders or chronic physical conditions, and is associated with high overall mental illness severity. Differences among older Blacks highlight the need for further research on this population to ensure appropriate treatment is being provided to these groups.
FunGene: the functional gene pipeline and repository

Ribosomal RNA genes have become the standard molecular markers for microbial community analysis for good reasons, including universal occurrence in cellular organisms, availability of large databases, and ease of rRNA gene region amplification and analysis. As markers, however, rRNA genes have some significant limitations. The rRNA genes are often present in multiple copies, unlike most protein-coding genes. The slow rate of change in rRNA genes means that multiple species sometimes share identical 16S rRNA gene sequences, while many more species share identical sequences in the short 16S rRNA regions commonly analyzed. In addition, the genes involved in many important processes are not distributed in a phylogenetically coherent manner, potentially due to gene loss or horizontal gene transfer. While rRNA genes remain the most commonly used markers, key genes in ecologically important pathways, e.g., those involved in carbon and nitrogen cycling, can provide important insights into community composition and function not obtainable through rRNA analysis. However, working with ecofunctional gene data requires some tools beyond those required for rRNA analysis. To address this, our Functional Gene Pipeline and Repository (FunGene; http://fungene.cme.msu.edu/) offers databases of many common ecofunctional genes and proteins, as well as integrated tools that allow researchers to browse these collections and choose subsets for further analysis, build phylogenetic trees, test primers and probes for coverage, and download aligned sequences. Additional FunGene tools are specialized to process coding gene amplicon data. For example, FrameBot produces frameshift-corrected protein and DNA sequences from raw reads while finding the most closely related protein reference sequence. These tools can help provide better insight into microbial communities by directly studying key genes involved in important ecological processes.
TreeRefiner: a tool for refining a multiple alignment on a phylogenetic tree

We present TreeRefiner, a tool for refining multiple alignments of biological sequences. Given a multiple alignment, a phylogenetic tree, and scoring parameters as input, TreeRefiner optimizes the sum-of-pairs function in a restricted three-dimensional space around the alignment. At each internal node of the unrooted tree, the multiple alignment is projected to the sub-alignments corresponding to the three neighboring nodes, and three-dimensional dynamic programming is performed within a user-specified radius r around the original alignment. We test TreeRefiner on simulated sequences aligned by several popular tools, and demonstrate substantial improvements in the percentage of correctly aligned positions.
Differentiating the use of gaze in bilingual-bimodal language acquisition: A comparison of two sets of twins with deaf parents

Signed languages make unique demands on gaze during communication. Bilingual children acquiring both a spoken and a signed language must learn to differentiate gaze use for their two languages. Gaze during utterances was examined for a set of bilingual-bimodal twins acquiring spoken English and American Sign Language (ASL) and a set of monolingual twins acquiring ASL when the twins were aged 2;0, 3;0 and 4;0. The bilingual-bimodal twins differentiated their languages by age 3;0. Like the monolingual ASL twins, the bilingual-bimodal twins established mutual gaze at the beginning of their ASL utterances and either maintained gaze to the end or alternated gaze to include a terminal look. In contrast, like children acquiring spoken English monolingually, the bilingual-bimodal twins established mutual gaze infrequently for their spoken English utterances. When they did establish mutual gaze, it occurred later in their spoken utterances and they tended to look away before the end.