cssi/SciSciGPT-SciSciNet huggingface dataset:
Control-matched analysis of laser in situ keratomileusis outcomes in high myopia.

Purpose To evaluate the outcomes of laser in situ keratomileusis (LASIK) for high myopia. Setting Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA. Methods The refractive and visual outcomes in 320 eyes (227 patients) that had LASIK for high myopia (spherical equivalent [SE] −6.00 to −10.00 diopters [D]) were analyzed. Two hundred fifty-eight eyes that had LASIK for low myopia were reviewed, and a subsequent control-matched comparative analysis of visual outcomes in highly myopic eyes (SE −7.54 ± 1.43 D) versus low myopic eyes (SE −2.26 ± 0.51 D) was performed after controlling for preoperative and surgical parameters. Descriptive and control-matched analyses of eyes with thick corneal pachymetry (≥570 μm) versus eyes with thinner corneal pachymetry (≤530 μm) were performed to evaluate the influence of corneal pachymetry on visual outcomes of LASIK for high myopia. Results The postoperative uncorrected visual acuity (Snellen; mean −logMAR ± SD) in the low myopia group (20/22; 0.04 ± 0.11) was statistically significantly better than in the high myopia group (20/26; 0.11 ± 0.18) ( P = .006). More eyes in the low myopia group (84.7%) than in the high myopia group (56.9%) achieved an SE within ±0.5 D ( P Conclusion Laser in situ keratomileusis for high myopia was safe, although the efficacy and predictability was slightly lower than for low myopia. There was no relationship between preoperative pachymetry and visual and refractive outcomes.
Understanding heroin as a "rational addiction".

This paper makes some interpretations on the Becker and Murphy model of rational addiction so as to consider policy issues beyond the discussion of the effects of price on heroin consumption. Through
Mechanism of retinoid-induced activation of latent transforming growth factor-β in bovine endothelial cells

Cell-associated plasmin is a putative physiological activator of latent transforming growth factor-beta (LTGF-beta). Since retinoids enhance the production of plasminogen activator (PA) and thereby increase cell-associated plasmin activity, we tested the possibility that retinoids might induce the activation of LTGF-beta using bovine endothelial cells (ECs) as a model system. ECs treated with physiological concentrations of retinol or retinoic acid formed active TGF-beta in the culture media in a dose- and time-dependent fashion. Cells were treated with 2 microM retinol for 24 h, and the amount of TGF-beta produced during a subsequent 12-h incubation period was measured. Out of a total of 14 pM LTGF-beta secreted, 0.7 pM was converted to active TGF-beta. Northern blot analyses showed that mRNA levels for TGF-beta 2 but not for TGF-beta 1 increased in cells treated with retinol. Inclusion of either inhibitors of PA or of plasmin or antibody against PA in the culture medium as well as depletion of plasminogen from the serum blocked the formation of TGF-beta, suggesting that PA, plasminogen, and the resulting plasmin are essential for activation of LTGF-beta in retinoid-stimulated cells. Antibody against the LTGF-beta binding protein blocked activation implying that localization of LTGF-beta through its binding protein may be important. However, inhibition of binding of LTGF-beta to the cell surface mannose 6-phosphate receptor did not prevent activation. These data indicate that retinoids up-regulate the production of LTGF-beta in ECs and induce activation of LTGF-beta, perhaps, by increasing PA and plasmin levels. Thus, TGF-beta might be a local mediator of some of the biological activities of retinoids both in vivo and in vitro.
The tides of Io

A theory is developed for the origin and evaluation of the orbital resonances between the Galilean satellites Io, Europa and Ganymede as a result of the effects of dissipative tides in Jupiter and its satellites. Following a preliminary consideration of the consequences of tidal interaction for satellite orbits and a comprehensive Hamiltonian theory of the resonance interactions which allows terms up to third order in eccentricity to be included, a dynamic model of the origin and evolution of the resonance locks is presented in which the relative expansion of the orbits by tidal torques from Jupiter together with tidal dissipation in Io lead to the rapid driving out of Io until it is captured into a 2:1 resonance with Europa and the resonance with Ganymede is achieved. Consideration of the effects of other commensurabilities on the orbital evolution of the system reveals that second-order Laplace-like resonances would act to excite free eccentricites, while the resonances associated with the two-body 3:1 commensurability could not have been encountered. Analysis of the hypothesis that the Laplace relation is primordial shows that the bounds on the tidal dissipation of Jupiter still can not be relaxed. Recent determinations of the tidal dissipation in Jupiter are discussed, and it is noted that none is sufficiently small to be consistent with the high heat flux estimates for Io. Finally, the possibility of the observational determination of the tidal dissipation in Jupiter by the measurement of the secular acceleration of Io's main motion is considered.
Levi's account of preference reversals

This paper argues that Levi’s account of preference reversals is only a limited success. Levi succeeds in showing that an agent acting in accord with his theory may exhibit reversals. Nevertheless, the specific account that Levi presents in order to accommodate the behavior of experimental subjects appears to be disconfirmed by available evidence. BIOGRAPHICAL NOTE Erik Angner is a graduate student in the Department of History and Philosophy of Science and in the Department of Economics at the University of Pittsburgh. He is the co-author (with George Loewenstein) of ‘Predicting and Indulging Changing Preferences,’ to appear in Loewenstein, Read, and Baumeister (eds) Time and Decision: The economics and psychology of intertemporal choice (New York: Russell Sage).
Impacts of spatially and temporally varying snowmelt on subsurface flow in a mountainous watershed: 2. Subsurface processes

Abstract The impacts of spatial and temporal variations of snowmelt recharge on subsurface flow in a small mountainous watershed were investigated using field measurements and numerical simulations. A two-dimensional, variably saturated flow model (VAM2D) was used to characterize the hillslope aquifer and to delineate subsurface flow mechanisms. Spatially varying snowmelt along a hillslope transect described in the preceding paper were used as input for the subsurface flow analyses. Simulations indicated that the heterogeneous hillslope aquifer provides hydrogeological conditions for confined and unconfined groundwater flow depending on the extent of snowmelt recharge. The spatial and temporal distribution and amount of snowmelt recharge play important roles in determining when flow is governed by confined and unconfined flow. Results showed that the VAM2D model was able to simulate piezometric measurements reasonably using calibrated hydraulic parameters. Sensitivity analyses showed that the flow regime ...
On the Radiative Damping of Atmospheric Waves

General expressions for computing time constants for radiative decay of harmonic temperature perturbations in planetary atmospheres are developed. Four spatial scales are shown to be generally important: the scale height of the atmospheric absorber, the absorption mean free path for thermal radiation, the altitude above the planetary surface, and the wavelength of the temperature perturbation. Atmospheric inhomogeneity is particularly important when the radiation mean free path and the vertical wavelength divided by 2 pi both exceed the absorber scale height. The surface is very important for wave decay at altitudes less than a few radiation mean free paths, and its effect depends on a comparison of the surface response time and the lifetime of the atmospheric perturbation. The surface response time depends on the conducting and emitting properties of the surface material and on the strength of turbulence in the planetary boundary layer. The additional influence of chemical reactions and phase changes on radiative damping is discussed, and several assumptions inherent in the development of the general expressions for time constants are evaluated. Terrestrial examples are used for purposes of illustration, but the development is kept sufficiently general so that the results remain applicable to most situations on other planets.
The social self and the social brain: a perspective of cultural neuroscience

Social and behavioral sciences have long conceived the human mind as an autonomous computational machine. However, recent developments in several fields of research including socio-cultural psychology, evolutionary psychology, and neuroscience among others have converged to suggest that the human mind -- with all neural mechanisms underlying it -- is biologically prepared and, yet, it is fully shaped by, and thus can only be completed by, each person's active participation in the symbolic world of culture. In my presentation, evidence for this thesis is reviewed to suggest that the human agency (the self) and the neuronal component processes constituting the self (the brain) are socio-culturally conditioned and, as such, they can show remarkable different characteristics depending on the socio-cultural environments in which they are engaged. This new, more expanded view of personhood offers important implications for intercultural collaboration.
A Simulation of Alberta Cumulus

Abstract A two-dimensional cloud model was used to simulate an Alberta, Canada, seeding experiment that was conducted on 24 July 1979, by the Alberta Research Council. The simulation reproduced some of the characteristics of the silver iodide seeded cloud in the actual case studies. This simulated cloud was also allowed to develop naturally and, in a third simulation, as a CO2 seeded cloud. A stratus layer was reproduced in the simulations, as well as the cloud used in the seeding simulations. The model was similar to those in previous papers, but there have been enhancements. Cloud ice was simulated as a bulk field with the total mass of ice; this was the sole predictor in the previous papers, while here an additional predictor, total number of ice crystals, was added. In the seeding simulations, the silver iodide produced a longer lasting seeding effect than the carbon dioxide. The carbon dioxide fell out of the cloud in minutes, while the silver iodide was carried around by the air flow for an indefini...
Pollaczek polynomials and Pade´ approximants: some closed-form expressions

Recently, some work has been devoted to the task of obtaining closed-form expressions for important classes of orthogonal polynomials. This has been done successfully for the associated Jacobi polynomials and their special cases, including the associated Laguerre and Hermite polynomials. Such expressions allow one to write closed-form expressions for the [n − 1/n] Pade approximants to important transcendental functions, for instance, expressions for the associated Jacobi polynomials provide in closed form the truncates of Gauss' continued fraction. In this paper, we continue this work by developing closed-form expressions for the Pollaczek polynomials Pnλ(x; a, b,c). These expressions involve a finite number of terms, each algebraic in character. This is to be contr with the traditional representation, which is a ratio of cross products of Gaussian hypergeometric functions, an expression not algebraic in the variable and not identifiably a polynomial. We examine some special cases of this formula, including the associated ultraspherical polynomials and the Chihara-Ismail polynomials. Finally, we determine the [n − 1/n] Pade approximants to a certain ratio of Gaussian hypergeometric functions.
Visual evoked magnetic fields reveal activity in the superior temporal sulcus

Evoked magnetic fields to randomized infrequent omissions of visual stimuli resulted in a magnetic field pattern over the right hemisphere consistent with a dipolar source and led to localization of this source within the superior temporal sulcus. Previous investigations using implanted microelectrodes, ablation/lesion procedures in monkeys and observations of behavioral anomalies following injury in humans have already indicated the importance of the inferior portions of the temporal lobe in visual processing. However, until now, no method was available to study noninvasively the role of temporal cortex during visual processing.
The Politics of Studying Politics: Political Science Since the 1960s

The field of political science has undergone significant change since the 1960s. The major shift was toward far greater quantification in the scholarly analyses. That movement sparked enduring controversies. These include disputes pitting scientific detachment against political relevance; specialization against accessibility; and quantitative against qualitative analysis. This article traces the contours of these controversies and offers some reflections on the discipline’s possible future.
Rapid Communication Isolation and Characterization of the Promoter of the Human GABAA Receptor α1 Subunit Gene

The GABAA receptor, as assessed by ligand binding and chloride flux measurement in vivo and in vitro, is down-regulated in response to chronic benzodiazepine exposure. The mRNA levels of the alpha 1 and gamma 2 subunits of the receptor are also reduced. We have isolated the promoter of the gene encoding the alpha 1 subunit of the GABAA receptor to elucidate the regulatory mechanism of its expression. A DNA segment 650 bp long has been isolated that includes 151 bp of untranslated 5' end of the cDNA sequence and 500 bp of potential promoter-enhancer region. The transcriptional activity of this DNA segment linked to the firefly luciferase gene showed a strong orientation specificity. The promoter activity was localized to a 60-bp segment by deletion mapping. Mobility shift binding assay results suggest that this segment may interact with one or more factors in HeLa cell nuclear extracts to form a transcriptional complex. Primary cultures of embryonic chick cortical cells transfected with the promoter-luciferase construct were treated chronically with lorazepam. Transcriptional activity of this promoter construct was strongly repressed by chronic administration of lorazepam.
Size-controlled synthesis of gold nanoparticles via high-temperature reduction.

Size and dispersity control of metallic nanoparticles is of fundamental necessity for their useful chemical implementation. A single-step synthesis of Au nanoparticles 4−15 nm in diameter and with low polydispersity is presented. Amine-induced reduction of a Au(I) precursor in the presence of coordinating ligands leads to nucleation of small particles which ripen to form larger particles. The rate of particle growth and subsequent aggregation is strongly dependent on the relative concentrations of protecting ligands and is monitored by both transmission electron microscopy and UV−visible absorption spectroscopy.
Abiotic conditions affect floral antagonists and mutualists of Impatiens capensis (Balsaminaceae)

Premise of the study While the effect of abiotic factors on leaf herbivory is well known, the relative importance of abiotic conditions influencing both mutualists and antagonists is less well understood. Species interactions could enhance or reduce the direct effects of abiotic factors, depending on how mutualists and antagonists respond to abiotic conditions. Methods We manipulated soil nutrients and shade in a factorial design and measured soil moisture in the annual Impatiens capensis. We then measured interactions with mutualists (two pollinating species) and antagonists (herbivores, florivores, nectar thieves, and flower bud gallers), as well as plant growth, floral rewards, and plant reproduction. Key results Fertilizer increased plant growth, floral attractiveness, mutualist and antagonist interactions, and plant reproduction. Shade had no effects, and soil moisture was negatively associated with plant growth and reproduction. All effects were additive. Mutualist and antagonist floral interactions both increased on fertilized plants, but antagonists increased at a greater rate, leading to a larger ratio of antagonist to mutualist interactions on fertilized plants. Despite having more antagonists, fertilized plants still had significantly higher reproduction, suggesting higher tolerance to antagonists. Conclusions Abiotic effects can have consistent effects on antagonists and mutualists, and on both floral and leaf antagonists. However, tolerance to antagonisms increased in favorable conditions. Thus, the direct positive effects of favorable abiotic conditions on plants outweighed negative indirect effects via increased antagonisms, which may lead to selection to grow in high-nutrient microsites in spite of increased herbivory.
In-situ reflection high-energy electron diffraction study of epitaxial growth of Cu on NaCl (100) under oblique angle vapor deposition

Abstract Epitaxial growth of copper on annealed NaCl(100) surface was carried out using thermal evaporation at an oblique angle of incidence (75 ± 5)° with respect to the substrate normal. The substrate was kept at a temperature of (150 ± 5)°C. The crystalline structure of the Cu film was studied in situ by reflection high energy electron diffraction at various deposition times. We observed that the film grows through nucleation of epitaxial islands followed by coalescence and then flattening of the film. The chevron shaped diffraction patterns formed by the refraction effect of electrons were used to identify the crystal facets. With longer deposition times, instead of columnar structures, a continuous epitaxial film was formed despite the oblique angle incidence of the vapor. The morphology of the final film was characterized ex situ by atomic force microscopy and shows L-shaped pores asymmetric with respect to the vapor incident direction.
PE Lipids in Single SNARE Vesicle Fusion Assay on Supported Membranes Promote Docking and Reduce the Number of SNARE Complexes Required for Fast Fusion

SNARE proteins are the core of the membrane fusion machinery in mammalian cells. Both in vitro and in vivo studies focus mostly on neuronal SNAREs (syntaxin1A, SNAP25, synaptobrevin2), which are involved in Ca2+ regulated exocytosis of synaptic vesicles. A recently developed single vesicle SNARE-mediated fusion assay in planar supported bilayers allows us to study individual docking and fusion events with a millisecond time resolution in a well-controlled lipid environment. Although, the fusion time in this assay is differently defined than in cellular settings, various parameters describing SNARE-mediated membrane fusion can be obtained, including the efficiency of vesicle docking and the probability of fusion after docking. Additionally, the number of particles in the fusion site and their activation rates can be determined from modeling of the fusion kinetics data.To better mimic the composition of the plasma membrane, we added various concentrations of PE and PS to our standard PC/Chol mixture. We observed a 1.5- to 3-fold increase in docking efficiency when the PE content was raised from 0 to 30%. In contrast, the fusion probability decreased 3- to 6-fold compared to PC/Chol membranes. Interestingly, including PE only in the vesicle membrane was sufficient to cause these effects. A detailed analysis of the fusion kinetics revealed that the fusion rate did not change significantly while the number of SNARE complexes that drive fast membrane fusion decreased with 3 complexes constituting the minimal fusion site. These results are rationalized with a model, in which fewer SNAREs are required to overcome the lower activation energy barrier in the presence of negative curvature-promoting PE than the higher activation energy that is likely present in the absence of PE.
Layered manufacturing for scientific visualization

From the moment we're born, we learn to use and depend on our sense of touch to gain knowledge and understanding of the world around us. Today, it can also be exploited to understand scientific data. Rapid prototyping, or layered manufacturing (LM), is a mainstream technology in engineering product development, enabling engineers to create prototype parts from new designs before their organizations invest in final production. The Center for Visualization Prototypes (CVP) at Oregon State University (originally at the San Diego Supercomputer Center) uses LM technology to create 3D visualization hard copies, collaborating with geologists, astronomers, oceanographers, cartographers, biomedical researchers, chemists, and other scientists to enhance data understanding. During its 10 years of operation, it has fabricated more than 1,000 physical models, helping them visualize their data.
Subgrid resolution of flow and force fields.

By means of spline fitting, both while converting a Lagrangian distribution of field sources onto an Eulerian grid, and while interpolating the field from its Eulerian grid to the Lagrangian positions of the responding elements, one achieves effective resolution down to about one-eight of a grid mesh unit. One also avoids discontinuities and noise due to cell boundary crossings.
The nucleotide sequence of the dimeric precursor to glutamine and leucine transfer RNAs coded by bacteriophage T4.

Abstract The nucleotide sequence of a precursor to glutamine and leucine transfer RNAs coded by bacteriophage T4 is presented. The sequence derivation relied on, and was thus facilitated by, knowledge of the previously determined sequences of the mature tRNAs. The molecule is dimeric; the single polynucleotide chain contains the sequences present in two tRNA species. The dimer contains only six precursor-specific residues, all of which are present at the 5′ terminus. The 3′ C-C-A OH terminus of the mature leucine tRNA is present at the 3′ end of the precursor. In contrast, the 3′ terminal C-C-A sequence of mature glutamine tRNA is not found in the precursor and must therefore be added post transcriptionally. The dimeric precursor can undergo endonucleolytic cleavage by purified ribonuclease P to generate the correct 5′ termini of the mature tRNAs. Sequence comparisons with other phage and bacterial tRNA precursors known to be substrates for this enzyme force the conclusion that recognition by RNAase P is other than sequence-specific.
Molecular Simulations of PIM-1-like Polymers of Intrinsic Microporosity

Polymers of intrinsic microporosity, or PIMs, are characterized by rigid and nonlinear or nonplanar backbones that inhibit space efficient packing, thus creating microporosity. PIM-1 has been well studied by both simulations and experiments and is compared in this work to two different PIM-1-like polymers, PIM-1c and PIM-1n. A detailed method for the generation of representative structures, including charge assignment from ab initio calculations, is presented along with simulated characterization of the pore size distributions, surface areas, structure factors, and methane adsorption isotherms. Simulated scattering for PIM-1c and PIM-1n show similar characteristic peaks as PIM-1, suggesting similar conformations. Adsorption isotherms of methane in PIM-1, PIM-1c, and PIM-1n were also predicted and compared to experimental data for PIM-1.
Synthesis and structural characterization of a Cu(I) dimer of a tris(oxazoline) ligand

Abstract The synthesis of a new tripodal tris(oxazoline) ligand, tris[4,4-dimethyl-2-(4,5-dihydrooxazolyl)]methylamine is described, and details of the X-ray crystal_structure of its Cu(I) complex are presented. The complex crystallizes as a dimer in the triclinic space group P 1 . Each Cu(I) ion is coordinated in a distorted trigonal geometry by two oxazoline groups from one tripod and a third oxazoline from the second ligand. The Cu(I)-Cu(I) distance is 5.7 A. The CO adduct of the complex exhibits ν(CO)= 2066 cm −1 .
Atrial flutter with 2:1 A-V conduction and Mobitz type II-like block in the left bundle branch.

This article presents the data of a patient who manifested the phenomenon of intermittent and transient left bundle branch block (LBBB) and subsequently Mobitz type II-like block in the left bundle branch (LBB). The assumption is made that this uncommon tachyarrhythmia occurs only in hearts with latent localized organic His-Purkinje system disturbance and made evident by the effect of supraventricular tachycardia. The regularity of the R-R interval, occurrence of two consecutive aberrant QRS complexes of similar duration without altering the R-R interval, and the conversion of the tachycardia to normal sinus rhythm with normal QRS complexes by application of carotid massage, all lend support to a unifocal, supraventricular origin of tachycardias with alternant QRS complexes. The constant and stable duration of all the ventricular beats with LBBB pattern, preceded and followed by normal ventricular complexes along with changing conduction ratios of 3:1 and 2:1 LBBB suggested Mobitz type II-like response in the LBB.
Barycentric basis functions on mixed triangular-quadrilateral meshes for integral equations

New quadrilateral barycentric meshes (QBMs) are introduced for mixed triangular/quadrilateral discretizations in solving surface integral equations. By dividing a triangle into three quadrilaterals and a quadrilateral into four quadrilaterals, new original- and dual- basis functions (BFs) are defined where the building-blocks are quadrilateral edge BFs on QBMs. The QBM BFs require a small number of unknowns with low computational time and memory costs. Numerical examples validate the performances of the proposed BFs.
Do Rooms Managers Exhibit Expense Preference Behavior in Nevada Casinos

Within the hospitality industry, the largest expense is payroll, and it is often considered one of the most controllable. Expense preference theory postulates that managers may focus more on maximizing their own utility by overspending as opposed to firm profit maximization. The purpose of this study is to evaluate if hotel managers in Nevada casinos exhibit expense preference behavior by overstaffing. Results of various regression models show that occupied rooms is positively and significantly related to rooms payroll. In one model, there is a modestly significant relationship between market concentration and rooms payroll. Results also show that after accounting for other variables, there is no significant relationship between a recession and rooms payroll.
Algorithms for the rapid computation of classical cross sections for screened Coulomb collisions

Abstract The development of medium energy backscattering with ions whose energies are as low as 50 keV and whose masses range up to that of 12C+ has generated the need for accurate and efficient mathematical methods for the computation of classical cross sections for screened Coulomb collisions. This paper presents a procedure for the computation which preserves most of the accuracy of more elaborate numerical solutions and is fast enough for all but the most time consuming Monte Carlo calculations. Comparisons are made between this approach and previous computations and approximations, and between the computed scattering cross sections for several screening functions.
Multivariate examination of Fe(II)/Fe(III) cycling and consequent hydroxyl radical generation.

The introduction of Fe(II)aq into aerated solutions resulted in net Fe(II) oxidation with concomitant, rapid Fe(II)/Fe(IIII) cycling and concurrent generation of reactive oxygen species. The effect of mixtures of naturally occurring solutes on Fe(II)/Fe(III) cycling and the concurrent oxidation of dissolved organics is reported. The experimental strategy was based on a multivariate, microscale, high-throughput approach for evaluating the effect of covarying concentrations of bromide, iodide, Suwannee River natural organic matter (SRNOM), chloride, and total carbonate species. Superoxide and HO• were evaluated at the center point condition of the experimental design with selective scavengers (superoxide dismutase and benzoic acid). The rate of Fe(II) oxidation decreased in the presence of these scavengers, indicating it is a function of oxygen, superoxide, and HO•. HO• generated during Fe(II)/Fe(III) cycling was quantified with the selective probe 1,3-dicyanotetrachlorobenzene (DCTCB). Through the range of...
All-or-none learning and the role of repetition in paired-associate learning.

The learning of a list of stimulus-response items is a two-stage process involving response learning and association. It is assumed that both stages are learned in an all-or-none fashion. Subjects were trained to learn a list of paired-associate items with Rock9s substitution procedure. Their performance could be predicted from the all-or-none theory with parameter estimates based upon the performance of a different group of subjects who learned the same items under normal conditions.
Community Policing, Workplace Structure and Attitudes Toward Lesbians and Gay Men and their Civil Liberties

While criminal justice workplaces, such as the police and prisons, are noted for reproducing both gender inequality and inequality based on sexuality or sexual orientation, this paper examines whether reorganizing the workplace can alter those interactions and reduce inequality. We draw on survey data from a police department to theorize the likely impact of the move toward community policing and rehabilitative models of justice on the attitudes of heterosexual sworn officers and civilian employees toward lesbians and gay men and their civil rights. Our analysis shows that sworn officers and civilian employees’ attitudes toward community policing and rehabilitation significantly affect their views on lesbians and gay men and their civil liberties both directly and indirectly. We conclude by suggesting the policy implications of our findings and avenues for future research.
Robotic Assembly of Space Solar Power Facilities

This paper profiles research relating to the robotic assembly, inspection, and maintenance of space solar-power facilities. Free-flying robots, fixed-base manipulators, and attached mobile manipulators are examined, the technical challenges facing them are outlined, and their roles in the construction process are illuminated. Themes include autonomous materials delivery, warehousing, large-scale payload handling and mating, payload attachment in confined spaces, and inspection. Research has addressed a fraction of the technologies needed to perform reliable autonomous assembly, inspection, and maintenance. Areas in need of further development are examined and potential research is outlined. Current technology cannot fulfill the requirements of orbital construction. The research and development needed can be completed in the near future, and substantive assembly inspection and maintenance can be achieved.
Revisiting intercultural communication competence: Where to go from here

Abstract This short essay is a reflection and assessment of 25 years of scholarship on the important topic of intercultural communication competence. The essay acknowledges significant theoretical contributions to date, including the ‘ABC’ (affect, behaviors and cognition/knowledge) triumvirate of most current models and describes three suggestions for future theoretical research: (1) move beyond individual-focused, reductionistic models to frameworks to capture a more holistic, relational, and spiritual view of intercultural communication competence. (2) Move from a focus on national culture groups that are presumed to be homogenous, and from an implicit conceptualization of culture as bounded and stable to conceptualizations that acknowledge the fluid, dynamic, contested nature of cultures, multiple cultural identities, and intercultural interactions and (3) acknowledge that power relations are part of every intercultural encounter. Looking forward, the essay proposes a dialectical approach – emphasizing the ongoing, processual, the both/and (contradictory) – that allows for a complex, dynamic, historically- and contexually-situated conceptualization of intercultural communication competence.
Lower Serum Thyroxine Levels in Rats following Prenatal Exposure to Ethanol

Fetal alcohol syndrome (FAS) is noted for poor growth, developmental delays, and mental retardation. In animals, prenatal alcohol exposure alters anatomical, physiological, and neurochemical maturation and produces behavioral changes similar to those in children. Since thyroid hormones are critical trophic factors for normal somatic and neural maturation, and since fetal thyroid hormones are profoundly affected by acute maternal ethanol administration, we hypothesized that postnatal effects of prenatal alcohol exposure may be related to abnormal thyroid hormone development. We report here that young rats exposed to alcohol in utero have significantly lower serum total thyroxine (T4) concentrations than normal and pair-fed control rats. The results suggest prenatal ethanol exposure may compromise thyroid development in ways not attributable to undernutrition or developmental delays alone. Lowered total T4 levels may be a teratogenic outcome of prenatal alcohol exposure, which could contribute to impaired growth, altered neural organization, and behavioral dysfunction.
The complement system in rheumatoid synovitis. I. An analysis of complement component activities in rheumatoid synovial fluids.

Stoichiometric hemolytic assays were used to measure the activities of the first four reacting components of the complement sequence in synovial fluids from patients with seropositive or seronegative rheumatoid arthritis or degenerative joint disease. The pattern of component reductions in the seropositive rheumatoid arthritis fluids was consistent with activation of the complement system by an intra-articular immunologic process.
The incorporation of 1,7-C14-pimelic acid into biotin vitamers.

Abstract Indirect evidence accumulated over the past twenty years implicate both pimelic acid and desthiobiotin as possible intermediates in the biosynthesis of biotin (duVigneaud, Dittmer, Hague and Long 1942; Eakin and Eakin 1942; Tatum 1945; Dittmer, Melville and duVigneaud 1944). The present report, which is part of a study on the mechanism of biotin biosynthesis (Eisenberg 1962), shows the incorporation of radioactive pimelic acid into the biotin vitamers synthesized by Phycomyces blakesleeanus. While this work was in progress, a similar study was reported with Aspergillus niger (Elford and Wright 1962).
Message formulation, organization, and navigation schemes for icon-based communication aids

Individuals with severe speech and motor impairments rely on assistive communication devices to convey their needs and desires in social, educational, and vocational situations. Users with limited motor control or literacy often choose to use icon-based devices that afford increased speed of message formulation at the cost of fully generative language formulation on letter-based devices. A major challenge with large vocabulary icon-based systems is rate of communication. Message formulation, vocabulary organization, and navigation schemes can be used to mitigate the trade-off between vocabulary size and communication rate. This paper summarizes our research efforts to leverage semantic frame theory, situational context, and rapid serial visual presentation to improve message formulation speed and completeness in our iconCHAT and RSVP iconCHAT systems. Usability data and persisting challenges are discussed.
Organ Shortage: The Greatest Challenge Facing Transplant Medicine

The success of organ transplantation as a treatment for end-stage organ disease has yielded a series of ethical quandaries originating from the issue of organ shortage. Scarcity of organs for transplantation necessitates formulation of just and fair allocation policies as well as ethically viable solutions to bridging the vast gap between organ supply and demand. The concept of “triage” provides a useful paradigm in which to contextualize the organ shortage issue. This entails subjugating the welfare of the individual patient for the benefit of the wider community as an ethically justified response to the challenge of scarcity.
A ballistics analysis of the Deep Impact ejecta plume: Determining Comet Tempel 1's gravity, mass, and density

Abstract In July of 2005, the Deep Impact mission collided a 366 kg impactor with the nucleus of Comet 9P/Tempel 1, at a closing speed of 10.2 km s−1. In this work, we develop a first-order, three-dimensional, forward model of the ejecta plume behavior resulting from this cratering event, and then adjust the model parameters to match the flyby-spacecraft observations of the actual ejecta plume, image by image. This modeling exercise indicates Deep Impact to have been a reasonably “well-behaved” oblique impact, in which the impactor–spacecraft apparently struck a small, westward-facing slope of roughly 1 / 3 – 1 / 2 the size of the final crater produced (determined from initial ejecta plume geometry), and possessing an effective strength of not more than Y ¯ = 1 – 10 kPa . The resulting ejecta plume followed well-established scaling relationships for cratering in a medium-to-high porosity target, consistent with a transient crater of not more than 85–140 m diameter, formed in not more than 250–550 s, for the case of Y ¯ = 0 Pa (gravity-dominated cratering); and not less than 22–26 m diameter, formed in not less than 1–3 s, for the case of Y ¯ = 10 kPa (strength-dominated cratering). At Y ¯ = 0 Pa , an upper limit to the total ejected mass of 1.8 × 10 7 kg ( 1.5 – 2.2 × 10 7 kg ) is consistent with measurements made via long-range remote sensing, after taking into account that 90% of this mass would have stayed close to the surface and then landed within 45 min of the impact. However, at Y ¯ = 10 kPa , a lower limit to the total ejected mass of 2.3 × 10 5 kg ( 1.5 – 2.9 × 10 5 kg ) is also consistent with these measurements. The expansion rate of the ejecta plume imaged during the look-back phase of observations leads to an estimate of the comet's mean surface gravity of g ¯ = 0.34 mm s −2 (0.17–0.90 mm s−2), which corresponds to a comet mass of m t = 4.5 × 10 13 kg ( 2.3 – 12.0 × 10 13 kg ) and a bulk density of ρ t = 400 kg m −3 (200–1000 kg m−3), where the large high-end error is due to uncertainties in the magnitude of coma gas pressure effects on the ejecta particles in flight.
The psychoanalytic treatment of a preschool boy with a gender identity disorder.

A three-year, nine-month-old boy began analysis by wishing he was a girl and pretending he was a superheroine. Over the course of almost five years, the cross-gender defense against fear of loss of the object, anal loss, and castration by the object reorganized in all libidinal phases through early latency. Developmental arrests seemed to occur during the anal rapprochement and oedipal phases that led to observable cross-gender strivings by two and a half years of age. The role of early childhood illness, narcissistic vulnerability, mother's childhood wish for a sister, the mother's adult wish for a daughter, a shared fantasy between mother and child, identification with the perceived power and beauty of mother and grandmother, pathological sibling rivalry that influenced identification with his sister, were demonstrated in his play during sessions. Interwoven in the background was the impact of an emotionally absent father, a dying grandfather, and an accident-prone uncle. This paternal matrix seemed to ...
Low IFT drainage and imbibition

Experiments were performed in four cores to investigate the effects of interfacial tension (IFT) changes and phase density difference on drainage and imbibition of oil/water/alcohol mixtures. In imbibition experiments, in which the cores were initially saturated with oil, both total recovery and the rates of recovery increased when IFT and density differences were reduced, despite reduced capillary and gravity driving forces. Time scale analysis shows that a transition from capillary-dominated flow to gravity-dominated flow as IFT is reduced, accounts for the observations. At high ratios of capillary to gravity forces (hight inverse Bond numbers, NB−1) the flow is capillary dominated and counercurrent. At low NB−1, gravity segregation dominates the flow. When the initial wetting phase saturation is zero, snap-off residual oil droplets are partially suppressed for NB−1 < 1.0. When an initial oil saturation is present, however, entrapment of residual oil is not suppressed for NB−1 as low as 0.04. In free drainage experiments, in which a core filled with an equilibrated wetting phase was surrounded by an oil phase, the wetting phase was completely retained in the core for NB−1 > 1.0. For NB−1 < 1.0, however, gravity forces were sufficient to overcome capillary entry pressures and free damage occurred. Significant reductions in oil saturation (60%) were observed for NB−1 < 0.1. The potential for recovery of oil from fractured reservoirs based on free drainage during gas injection is discussed. Critical scaling shows that a multicontact miscible gas injection process can be used to create the low value of NB−1 required. Estimates of NB−1 for fractured reservoirs indicate that use of gravity drainage is possible even for low-permeability reservoirs as long as fractures exist with vertical connections of sufficient height.
Non-collagenous proteins of rat dentin. Evidence that phosphoprotein is not covalently bound to collagen

The non-collagenous proteins of rat dentin that remain firmly bound to the matrix after demineralization were studied in order to ascertain if they are covalently linked to insoluble dentin collagen. After solubilization with CNBr or with bacterial collagenase, unusually small amounts of dentin phosphoprotein were detected in the matrix. The phosphoprotein obtained by CNBr digestion of the matrix was separated from collagen peptides using two chromatographic steps. Thus even this small quantity of phosphoprotein found in decalcified rat dentin matrix was not covalently bound to collagen.
Chronic alterations in ovine maternal corticosteroid levels influence uterine blood flow and placental and fetal growth

Previous work from this laboratory demonstrated that the elevation of maternal plasma corticosteroid concentrations during pregnancy is important for the support of fetal development. Reducing ovin...
Transurethral Needle Ablation of the Prostate: A Minimally Invasive Treatment for Symptomatic Benign Prostatic Hyperplasia

Transurethral needle ablation of the prostate, a relatively new minimally invasive treatment modality for patients with bladder outlet obstruction attributable to an enlarged prostate gland, has undergone extensive evaluation by nu merous investigators worldwide. The results to date indicate that needle ablation is safe and effective for relieving symptoms in patients with benign prostatic hyperplasia, and the effect has been demonstrated to be durable for at least 2 years. Nevertheless, additional investigations with longer follow-up data are needed to address the important issues of extended durability (5 to 10 years) and biophysiologic mechanism of action. Comparisons between transurethral needle ablation of the prostate and transurethral resection of the prostate (TURP) have revealed that the subjective and objective measures of response are comparable, although TURP has consistently displayed a slight advantage over needle ablation for most variables analyzed, except quality of life score. The advantages of needle ablation over TURP are (1) performance in the office as an outpatient procedure, (2) no need for general or spinal anesthesia, (3) rapid recovery, (4) minimal side effects, and (5) one-time intervention. The following disadvantages exist with needle ablation: (1) it may not be indicated or effective in patients with large prostate glands (75 g or more); (2) no prostate tissue is available for histologic evaluation; and (3) no long-term efficacy or re-treatment rate data have been published. Overall, the available information indicates that transurethral needle ablation is a viable minimally invasive treatment that may be applicable in men with moderate to severe bladder outlet obstruction as a result of an enlarged prostate gland.
Genetic algorithm/neural network synergy for nonlinearly constrained optimization problems

Michalewicz and Janikow (1991) proposed a methodology for applying genetic algorithms to constrained optimization problems in which the constraint equations are linear. They show that the set of feasible solutions can be more thoroughly searched by requiring the genetic population to remain in the set of feasible solutions and propose adopting a weighted average rule for combining parent gene strings in genetic crossover. Because the set of feasible solutions is convex, the population remains feasible. Unfortunately, this technique does not extend to the general case of nonlinear constraints. The purpose of this paper is to present a general technique by which a population can be restricted to a set of feasible solutions, even when the constraints are nonlinear. The technique combines the strengths of neural networks with the strengths of genetic algorithms by substituting a neural network operator for the usual method of genetic crossover. >
A Method for Measuring Tension in Small Ligaments: An Application to the Ligaments of the Wrist Carpus

A new technique has been devised for measuring the in situ tension in small ligaments. It is based on measuring the tension in an axially loaded flexible cable with pinned endpoints by deflecting the cable laterally and measuring its lateral load and deformation. Studies were performed in which nylon line and bone ligament bone preparations were placed in a materials tester and loaded in axial tension. Axial load as measured by lateral load and deformation was found to agree with the known load to within 8 percent. The method was sensitive to error in determination of ligament length, nonperpendicularity of the laterally applied load to the long axis of the ligament, and when used in situ, impingement of the ligament on a third bone causing bending. A device, consisting of an LVDT mounted to a rigid frame with its core rod connected to a load cell, was developed. The position of the core rod was controlled by a manual screw drive, and a hook on the other end of the core rod was used to deflect the ligament laterally. This device was applied to the study of tensions in five ligaments of the palmar wrist carpus, in seven cadaver specimens. Results showed that the radioscaphocapitate (RSC) and radiolunate (RL) ligaments had significantly greater tensions than the lunotriquetral (LT), the triquetrocapitate (TC), and scaphocapitate (SC) ligaments. For the four positions of the hand tested, neutral, 14 deg radial and 14 deg ulnar deviation, and 28 deg of extension, ligament tensions were found to be unaffected by position.(ABSTRACT TRUNCATED AT 250 WORDS)