cssi/SciSciGPT-SciSciNet huggingface dataset:
Current account sustainability of ECOWAS countries

This paper examines current account sustainability of eight countries in the Economic Community of Western African States (ECOWAS); Burkina Faso, Cote d'Ivoire, Ghana, Mali, Niger, Nigeria, Senegal and Togo. The paper uses the intertemporal solvency framework of Hakkio and Rush (1991) and Husted (1992) and cointegration methodology to test for a long run relation between exports and imports items of the current account. Further, we estimate this long-run relationship using dynamic OLS. Our results show that only Senegal and Togo have sustainable current account positions. Of the others, Ghana and Niger have a statistically significant relation between exports and imports although it is not strong enough, and thus they continue to have vulnerable current account positions. The rest of the countries have unsustainable current account deficits. The paper argues that monetary, trade and political reforms are necessary to reduce vulnerabilities in external positions.
Wearable activity sensors and early pain after total joint arthroplasty.

A prospective observational cohort of 20 primary total hip arthroplasty (n = 12) and total knee arthroplasty (n = 8) patients (mean age: 63 ± 6 years) was passively monitored with a consumer-level wearable activity sensor before and 6 weeks after surgery. Patients were clustered by minimal change or decreased activity using sensor data. Decreased postoperative activity was associated with greater pain reduction (-5.5 vs -2.0, P = .03). All patients surpassed minimal clinical benefit thresholds of total joint arthroplasty (TJA) (Hip Disability and Osteoarthritis Score Junior 30.5 vs 20.8, P = .23; Knee Injury and Osteoarthritis Outcome Score Junior 23.3 vs 18.2, P = .77) within 6 weeks. Patients who objectively "take it easy" after TJA may experience less pain with no difference in early subjective outcome. Remote, passive analysis of outpatient wearable sensor data may permit real-time detection of early problems after TJA.
Shear Strengthened Granular Jamming Feet for Improved Performance over Natural Terrain

Walking on natural terrain like soil and rock is a challenging problem that has been approached from a variety of strategies such as using sophisticated control methods, compliant legs, and compliant feet. In this paper we explore how to modify granular jamming feet for walking applications by adding stabilizing internal structures. Previous work has explored how granular jamming technology can be used to create compliant and stiffness changing feet that enable locomotion over a diverse range of natural terrain by allowing robot feet to conform around 3D multicomponent terrain such as wood chips and gravel and stiffen, preventing slip. To date, no work has been done to tune granular jamming feet for the specific application of walking. We show that adding internal structures to granular jamming membranes can increase the force they are able to resist without slipping by 1.5x while maintaining their ability to conform around obstacles. When attached to a robot, we see increases in speed of up to 1.4x, decreases in the duty cycle necessary to reach desired foot trajectories of up to 5%, and increases in traction force of up to 1.2x over a diverse set of natural terrain.
Jokers’ pursuit of truth: critical policy analysis in the age of spectacle and post-truth politics

Critical policy analysis examining how powerful actors use educational policies to reproduce unequal social structures presents many challenges. These challenges are amplified by the politics of sp...
Immune Checkpoint Blockade in Gynecologic Cancers: State of Affairs

This review provides an update on the current use of immune checkpoint inhibitors (ICI) in female gynecologic cancers, and it addresses the potential of these agents to provide therapy options for disease management and long-term remission in advanced disease patients, where surgery, chemotherapy, and/or radiation fail to meet this goal. The topic of immune checkpoint inhibitors (ICI) blocking cytotoxic T lymphocyte associated protein-4 (CTLA-4) and the programmed death-1 (PD-1) axis has come to the forefront of translational medicine over the last decade for several malignancies. The text will focus primarily on a discussion of ovarian cancer, which is the most frequent cause of death of gynecologic cancers; endometrial cancer, which is the most often diagnosed gynecologic cancer; and cervical cancer, which is the third most common female gynecologic malignancy, all of which unfavorably alter the lives of many women. We will address the critical factors that regulate the outcome of these cancer types to ICI therapy, the ongoing clinical trials in this area, as well as the adverse immune responses that impact the outcome of patients given ICI regimens.
Constraints of Honey Production and Marketing in Ethiopia: A Review

Ethiopia has huge potential for beekeeping production and 1st in honey production in Africa because of its endowment with diversity in climate and vegetation resources offering potentially favorable conditions for beekeeping. It is important for sources of food and beverages, medication, income generation, creating employment opportunities, environmental balance through pollination. Even though it has a higher contribution, the sector is yet not potentially utilized due to various constraints. Therefore the objectives of this paper are to review the production constraints of honey in Ethiopia and to review the marketing constraints of honey in Ethiopia. Pests, Disease and Predators; weather problem; Shortage of bee forage; Absconding; shortage of trained manpower; shortage of equipment; poor management practices; chemicals; weak research and extension; poor infrastructures and etc. are constraints of honey production in Ethiopia. While linkages problem; lack of market center; lack of market information; price fluctuation; low awareness of post-harvest handling; lack of technology; poor market infrastructure, lack basic business concepts; and etc. are constraints honey marketing in Ethiopia. To overcome such constraints:- Adopting effective honeybee pests, disease and predators controlling methods; Introducing and expanding of full package improved beekeeping technologies with adequate practical skill; strengthen full package extension services; Support farmers for beekeeping business through credit availability, improving the barging power of beekeepers, strengthen linkage among different concerned institutions, cooperative formation, input supply, market facilitation and infrastructures as a whole; Giving attention on research and human resources development ; Expanding coverage of flowering plants especially economically important ones like horticultural crops and reducing the impact of agrochemicals and others are suggested recommendations.
Rabbi Dr. Sarah M. Tauber (June 22, 1966–August 28, 2020)

Rabbi Dr. Sarah M. Tauber was an assistant professor at the William Davidson Graduate School of Jewish Education of the Jewish Theological Seminary (JTS) and taught as a visiting professor at Union...
The International Labour Organisation in pursuit of decent work in Southern Africa: An appraisal

This article examines the role of the International Labour Organisation (ILO), regional standards, and the “decent work agenda” in addressing challenges facing non-standard workers in southern Africa. Employees in traditional full-time employment are well protected in some southern African states, but the regulation currently available is largely unable to protect non-standard workers, and in numerous instances workers are regarded as “non-standard”, on the basis of a narrow interpretation of the term “employee”. Casualisation and externalisation have resulted in the exclusion of numerous workers from the protection provided by labour legislation, and union cover for non-standard workers is very low. The article further discusses the relationship between non-standard employment and labour migration in southern Africa. Light is also shed on regional standards, the challenges of unemployment, poverty, and income inequality, and labour-market transitions in southern Africa.
Security Through Solidarity: How Populism Reshapes Global Governance

Scholars have long argued that international institutions solve cooperation problems through the timely, accurate provision of information. Yet, performing this role often requires international organizations (IOs) to rely on member states for essential data and details. What happens when members refuse to supply accurate information? We argue that IOs often respond by broadening their information base, increasing information sharing with each other. We test our argument using an original data set on information sharing among IOs in the development lending issue space. We show that when IOs face resistance from populist leaders in key member states, they sign more and deeper information sharing agreements with other institutions. To explore the mechanism driving these results, we supplement our main analysis with a case study of U.S. information sharing with IOs under the Trump administration. Our findings suggest that populism has reshaped global governance, causing IOs to deepen and strengthen global networks.
Reducing User Bias in X-ray Computed Tomography-Derived Rock Parameters through Image Filtering

Accurate representation of pore space is essential for predicting fluid flow through subsurface porous media. Pore volume fraction, geometry, and topology determine transport characteristics at the pore scale and are used to make upscaled projections about reservoir behavior. X-ray computed tomography (XCT) allows for nondestructive 3D imaging of rock core samples and can therefore provide valuable information about the pore network in situ, but segmentation of XCT datasets into pore and mineral space is not trivial. In this study, three filters (contrast enhancement, noise reduction, and beam hardening correction) were applied to XCT datasets of rock core samples prior to training class definition for machine learning-based segmentation. Porosities derived from segmented datasets with and without filtering were compared and were validated with experimental values. XCT-derived porosity had reduced variance and was closer to experimental data when all three filters were applied. A case study of one rock core sample compared pore size distribution and simulated permeability to experimental data. Computational fluid dynamics simulations of flow through the pore network using OpenFOAM showed improved consistency in permeability values when all three filters had been applied. This suggests that the application of these filters prior to machine learning training class definition can improve the reproducibility of the segmentation results and reduce user bias, thereby increasing confidence in digitally derived rock parameters. Reliable initial porosity and permeability data are critical for improving fluid transport and fate projections in a broad range of subsurface systems. .
Pinpointing the Emergence of the Company Limited by Guarantee in Company Law: Historical Origins and Modern Day Review

The origin of the "company limited by guarantee" is nearly impossible to pinpoint. While some experts believe that this type of business form sprang into being overnight, it is more likely that the company limited by guarantee slowly developed over centuries of time. The origins of the company limited by guarantee have a shadowy existence, which is likely attributable to the notion that this business form is comprised of bits and pieces of other business forms that existed in early English history.
Conceptualizing the Division of Household Labor

It is now more than 20 years since our attention was first directed to the “problem that has no name” (Friedan, 1963). In the decades that followed, a great many people—among them a number of social scientists—embarked on a search for the “right” name for the “wrongs” of women. Along the way, we “discovered” women’s growing labor force participation and its concomitant occupational sex segregation (e.g., Gross, 1968; Bo wen and Finegan, 1969); male/female wage differentials and sex discrimination (e.g., Mincer, 1962; Cain, 1966); the tyranny of biological, psychological, and medical labels for women’s complaints (e.g., Chesler, 1972; Ehrenreich and English, 1978; Smith and David, 1975); violence against women as more than perverted “love” (e.g., Millett, 1970; Brownmiller, 1975; Griffin, 1979; Walker, 1979); and most recently, male dominance in the everyday business of communication (e.g., Fishman, 1978; Zimmerman and West, 1975; West, 1982). The list goes on, with the manifestations of the “problem” stretching across class, culture, and social setting.
Contrasting chemiluminescent metal oxide formation: In the single collision reactions of boron with O2, NO2, N2O, O3 and ClO2

Abstract An intense source has been developed to study the reactions of boron ( 2 P) atoms with O 2 , NO 2 , N 2 O, ClO 2 , and O 3 . The chemiluminescent emissions which characterize the bimolecular reaction of boron with O 2 , N 2 O, ClO 2 , and O 3 are dominated by the A 2 Π-X 2 Σ + band system of BO. In contrast the chemiluminescence from the boron- NO 2 reaction is dominated by strong BO 2 A 2 Π u -X 2 Σ g emission.
A 54mW 1.2GS/s 71.5dB SNDR 50MHz BW VCO-based CT ΔΣ ADC using dual phase/frequency feedback in 65nm CMOS

A wide bandwidth VCO-based continuous-time ΔΣ modulator that uses combined phase and frequency feedback to mitigate VCO non-linearity and ease DEM timing requirement is presented. Fabricated in 65nm CMOS process, the prototype modulator operates at 1.2GS/s and achieves 71.5dB SNDR in 50MHz bandwidth while consuming 54mW of power, which translates to an FoM of 176fJ/conv-step.
Near-field source localization based on sparse reconstruction of sensor-angle distributions

In this paper, we consider a problem of near-field source localization using the sensor-angle distribution (SAD) that views the source range and direction-of-arrival (DOA) information as sensor-dependent phase progression. The SAD draws parallel to quadratic time-frequency distributions and, as such, is able to reveal the changes in the spatial frequency over sensor positions. In particular, for a moderate source range, the SAD signature is of polynomial shape, thus simplifying the parameter estimation. We consider sparse arrays where the array sensors are located on a grid but with missing positions. Sparse reconstruction techniques are used to estimate the SAD in the joint space and spatial frequency domain, and the results are then mapped back to source range and DOA estimation for source localization. The effectiveness of the proposed technique is verified using simulation results.
Evolving targeted therapies for right ventricular failure.

Introduction: Although right and left ventricular embryological origins, morphology and cardiodynamics differ, the notion of selectively targeted right ventricular therapies remains controversial.Areas covered: This review focuses on both the currently evolving pharmacologic agents targeting right ventricular failure (metabolic modulators, phosphodiesterase type V inhibitors) and future therapeutic approaches including epigenetic modulation by miRNAs, chromatin binding complexes, long non-coding RNAs, genomic editing, adoptive gene transfer and gene therapy, cell regeneration via cell transplantation and cell reprogramming and cardiac tissue engineering.Expert opinion: Strategies for adult right ventricular regeneration will require a more holistic approach than strategies for adult left ventricular failure. Instances of right ventricular failure requiring global reconstitution of right ventricular myocardium, attractive approaches include: i) myocardial patches seeded with cardiac fibroblasts reprogramme...
Molecular weight determinations by low-speed sedimentation equilibrium: A combined use of the nazarian equation and the griffith rapid equilibrium technique

Abstract A combined procedure, employing the Nazarian equation and the Griffith rapid equilibrium technique, is presented for the determination of molecular weights by low-speed sedimentation equilibrium using Rayleigh interference optics. This makes it possible to obtain a molecular weight measurement from one experiment in a relatively short period of time with high accuracy and comparatively simple calculations. Seven proteins ranging in molecular weight from 13,000 to 500,000 were examined, and the time to reach equilibrium was found to be linearly related to the log of the molecular weight, thus establishing the necessary criterion to use when deciding the duration of an equilibrium experiment in question. Finally, the Nazarian equation is shown to be ideally suited for use with the Edelstein-Schachman procedure for the determination of partial specific volumes.
A Proof-of-Concept Implementation of a Unit-Based Advanced Practice Registered Nurse (APRN) Role: Structural Empowerment, Role Clarity and Team Effectiveness

The quest for decreased cost of care and improved outcomes has created the need for highly effective clinical roles and teams. This article describes the role of a unit-based advanced practice registered nurse (APRN) within a proof-of-concept implementation of a new care delivery model, the Vanderbilt Anticipatory Care Team. Role clarity is central to both structural empowerment of the APRN and team effectiveness. A modified PeaceHealth Team Development Measure tool measured baseline role clarity as a component of overall team effectiveness. A role description for the unit-based APRN based on a comprehensive assessment of the proof-of-concept unit is provided.
Three 1-Aminocyclopropane-1-Carboxylate Synthase Genes Regulated by Primary and Secondary Pollination Signals in Orchid Flowers

The temporal and spatial expression patterns of three 1-aminocyclopropane-1-carboxylate (ACC) synthase genes were investigated in pollinated orchid (Phalaenopsis spp.) flowers. Pollination signals initiate a cascade of development events in multiple floral organs, including the induction of ethylene biosynthesis, which coordinates several postpollination developmental responses. The initiation and propagation of ethylene biosynthesis is regulated by the coordinated expression of three distinct ACC synthase genes in orchid flowers. One ACC synthase gene (Phal-ACS1) is regulated by ethylene and participates in amplification and interorgan transmission of the pollination signal, as we have previously described in a related orchid genus. Two additional ACC synthase genes (Phal-ACS2 and Phal-ACS3) are expressed primarily in the stigma and ovary of pollinated orchid flowers. Phal-ACS2 mRNA accumulated in the stigma within 1 h after pollination, whereas Phal-ACS1 mRNA was not detected until 6 h after pollination. Similar to the expression of Phal-ACS2, the Phal-ACS3 gene was expressed within 2 h after pollination in the ovary. Exogenous application of auxin, but not ACC, mimicked pollination by stimulating a rapid increase in ACC synthase activity in the stigma and ovary and inducing Phal-ACS2 and Phal-ACS3 mRNA accumulation in the stigma and ovary, respectively. These results provide the basis for an expanded model of interorgan regulation of three ACC synthase genes that respond to both primary (Phal-ACS2 and Phal-ACS3) and secondary (Phal-ACS1) pollination signals.
Heat of Respiration of Fresh Produce as Affected by Controlled Atmosphre

SUMMARY —The heat of respiration of fresh produce in controlled atmosphere (CA) storage was determined with a calorimeter to provide information on the refrigeration load imposed. The heat of respiration in air at the same temperature was also measured to enable direct comparison with the heat of respiration in CA. The calorimeter was a heavily insulated Dewar flask and the product was continuously flushed with either air or CA. The values obtained for the heat of respiration in air were in good agreement with those reported in the literature for these products. The heat of respiration (Btu/Ton-24 hr) in optimum CA with the ratio in CA to that in air given as a percent was as follows: Wando peas at 48°F—6,690, 31%; Thorogreen lima beans—2,290, 30%; cut Victory Golden sweet corn—3,810, 32%; Red Delicious apples—525, 28%. It was concluded that the heat of respiration of fresh produce in CA can be estimated by assuming that it is about 30% that in air.
Mental health consequences of the Chernobyl disaster

The psychosocial consequences of disasters have been studied for more than 100 years. The most common mental health consequences are depression, anxiety, post-traumatic stress disorder, medically unexplained somatic symptoms, and stigma. The excess morbidity rate of psychiatric disorders in the first year after a disaster is in the order of 20%. Disasters involving radiation are particularly pernicious because the exposure is invisible and universally dreaded, and can pose a long-term threat to health. After the Chernobyl disaster, studies of clean-up workers (liquidators) and adults from contaminated areas found a two-fold increase in post-traumatic stress and other mood and anxiety disorders and significantly poorer subjective ratings of health. Among liquidators, the most important risk factor was severity of exposure. In general population samples, the major risk factor was perceived exposure to harmful levels of radiation. These findings are consistent with results from A-bomb survivors and populations studied after the Three Mile Island nuclear power plant accident. With regard to children, apart from findings from ecological studies that lack direct data on radiation or other teratologic exposures and local studies in Kiev, the epidemiologic evidence suggests that neither radiation exposure nor the stress of growing up in the shadow of the accident was associated with emotional disorders, cognitive dysfunction, or impaired academic performance. Thus, based on the studies of adults, the Chernobyl Forum concluded that mental health was the largest public health problem unleashed by the accident. Since mental health is a leading cause of disability, physical morbidity, and mortality, health monitoring after radiation accidents like Fukushima should include standard measures of well-being. Moreover, given the comorbidity of mental and physical health, the findings support the value of training non-psychiatrist physicians in recognizing and treating common mental health problems like depression in Fukushima patients.
Lumbar ligamentum flavum: spatial relationships to surrounding anatomical structures and technical description of en bloc resection.

Background One structure, the ligamentum flavum, nearly always encountered in lumbar spinal operations, has not been examined as an important anatomical landmark. In this context, we describe its relevance in corridors of small surgical exposures created by minimally invasive spinal approaches. Material and Methods In cadaveric and intraoperative dissections, we introduce a systematic technique for resection of this ligament and clarify its anatomical relationships with the exiting nerve roots, pedicles, facet capsule, and midline epidural fat. Fixed human cadaveric spines were harvested en bloc to maintain the lower thoracic to sacral segments. A single coronal cut through the anterior portion of the pedicles ensured that the dorsal elements were intact. Viewed from the operative microscope, photographs depict the ligamentum flavum at various intraoperative steps. Results The ligamentum flavum can undergo safe en bloc sequential resection that widely exposes the disc space for discectomy and interbody fusion. Its superolateral and inferolateral attachments are identifiable landmarks, effective in locating the exiting nerve roots. Corners of the L4–L5 ligamentum flavum mark the axillae of the exiting nerve roots (i.e., its superolateral corner marks the axilla of the L4 nerve roots, and its inferolateral corner marks the shoulder of the L5 nerve roots). Conclusion Our cadaveric and microscopic surgical dissections show the ligamentum flavum as seen in the new corridors of small surgical exposures during minimally invasive surgeries of the lumbar spine. Identifying this landmark, surgeons can envision the location of the nerve roots to help prevent their injury.
Time-resolved evolution of fly ash during pulverized coal combustion

The time resolved evolution of ash during the combustion of individual char particles has been studied using a Montana lignite, a North Dakota Beulah lignite, and a synthetic char prepared from doped sucrose. The three chars were selected to illustrate the effects of macroporosity and mineral matter content on the ash evolution. The synthetic char is distinguished from the lignites by being macropore-free. The ash content was varied from 17%(Montana) to 37%(Beulah). When the chars are reacted under external-diffusion-controlled conditions, the mineral matter is released as the carbon surface recedes. The ash particles on the surface of the char aggregate and grow in size with increasing char burnout. The rate of growth of particle size increases markedly as the extent of burnout increases because of the increase in surface concentration of released ash. The ash sizes are larger for the char with the higher mineral content. As complete burnout is approached, however, the macroporous lignite chars fragment yielding smaller final ash particles than the macropore-free sucrose char. A percolation model applied to the ash formation processes was used to demonstrate the major features of the dependence of the time resolved evolution of ash on macroporosity.
Quasi-sliding mode control strategy based on multiple-linear models

In this paper, a multiple discrete quasi-sliding mode (QSM) control scheme is proposed for a general class of nonlinear discrete time systems with unknown dynamical equations, provided that input-output data is available for system identification. The self-organizing map (SOM) is employed to divide the state space into local regions such that it associates the operating region where a local linear model is the winner with a local quasi-sliding mode controller (QSMC). Switching of the controllers is done synchronously with the active local linear model that tracks the different operating conditions. The simulation results show that the proposed controller outperforms tracking the desired trajectory in noisy environments either with a global controller or simpler controllers based on multiple models.
Activity and photoregulated expression of PsPK3

The PsPK3 gene of the garden pea encodes a presumptive protein-serine/threonine kinase whose catalytic domain is closely related to the second messenger-dependent kinases. To demonstrate that PsPK3 is a functional protein kinase, its catalytic domain was expressed in and purified from Escherichia coli for in vitro activity assays. The recombinant catalytic domain autophosphorylated primarily on serines. We found previously that when 6-day-old etiolated pea seedlings are illuminated with continuous white light (WLc), PsPK3 transcript levels decline rapidly within apical buds, reaching their minimum levels within just a few hours of illumination. We asked whether PsPK3 transcript levels changed during seedling development using RNA gel blot analyses of total RNA purified from the apical buds and plumular hooks of seedlings ranging in age from 3 to 7 days. During seedling development in darkness, the amount of PsPK3 mRNA exhibited a modest decline. When etiolated seedlings were exposed to 1 day of WLc, PsPK3 gene expression in hooks was light-responsive even at the earliest stage of seedling development and became more responsive as the seedlings aged. We used antibodies directed against recombinant PsPK3 catalytic domain to ask whether light also regulates the abundance of PsPK3 polypeptides in the bud, hook, and upper portion of the stem of pea seedlings. PsPK3-related polypeptides are present in all three organ systems tested and their abundance is decreased by WLc in the hooks and stems of pea seedlings but not in apical buds. Therefore, the PsPK3 gene demonstrates discoordinate regulation of its polypeptide and mRNA abundances in greening pea seedlings.
Characterization of HIV infection and seroconversion by a stochastic model of the HIV epidemic

Abstract In this paper we use a stochastic model for the HIV epidemic in homosexual populations to characterize the HIV infection and seroconversion. Using computer generated data, we compare the fitting of infection distributions and of seroconversion distributions by different parametric models as well as by nonparametric methods. The nonparametric methods include the Kaplan-Meier method, EMS method, Bacchetti's method, and the spline approximation. The parametric models include most of the models which have been used in the literature. The comparison criteria are the chi-square statistic, the AIC (Akaike Information Criterion) and the residual sums of squares. The numerical results suggest that for the proportional mixing pattern, the EMS method, the spline method, Bacchetti's method, and the generalized log-logistic distributions with three and with four parameters provide better fitting for the infection and the seroconversion distributions in most cases. For the restricted mixing pattern, the EMS method, the spline method, Bacchetti's method, and some mixtures of distributions provide close fitting to the infection and the seroconversion distributions.
Conditioned approach-withdrawal behavior and some signal-food relations in pigeons: Performance and positive vs. negative “associative strength“

The location of pigeons was monitored during illuminations of a key (CS) presented in a positive, zero, or negative relationship with food for different groups of subjects. Birds approached a signal positively correlated with food and withdrew from a negatively correlated signal. When the probability of food in the absence of CS was increased from 0 to .2 while the probability of food during CS remained constant at .4, approach to CS declined. When the probability of food during CS increased from 0 to .2 while the probability of food in CS absence remained constant at .4, withdrawal from CS declined. No consistent approach or withdrawal appeared when the probability of food was the same (.4) during the presence and absence of CS. Our approach-withdrawal assay of positive and negative associative strength, which allows trial-by-trial measurement of overt performance during excitatory or inhibitory conditioning, was used to assess several predictions of the Rescorla-Wagner model of Pavlovian conditioning.
The Relationships between Cognitive Ability and Dynamic Decision Making.

This study investigated the relationships between cognitive ability (as assessed by the Raven Progressive Matrices Test [RPM] and the Visual-Span Test [VSPAN]) and individuals' performance in three dynamic decision making (DDM) tasks (i.e., regular Water Purification Plant [WPP], Team WPP, and Firechief). Participants interacted repeatedly with one of the three microworlds. Our results indicate a positive association between VSPAN and RPM scores and between each of those measures and performance in the three dynamic tasks. Practice had no effect on the correlation between RPM score and performance in any of the microworlds, but it led to an increased correlation between VSPAN score and performance in Team WPP. The pattern of associations between performance in microworlds and assessments of cognitive ability was consistent with the task requirements of the microworlds. These findings provide insight into the cognitive demands of dynamic decision making and the dynamics of the relationships between cognitive ability and performance with task practice.
The role of heme synthesis during the induction of hepatic microsomal cytochrome P-450 and drug metabolism produced by benzpyrene.

Abstract δ-Aminolevulinic acid synthetase, the initial and rate limiting step in hepatic heme synthesis, is induced by both benzpyrene and phenobarbital. Induction of this enzyme by benzpyrene results in the stimulation of glycine-2- 14 C incorporation into hepatic microsomal heme in vivo and in the induction of cytochrome P-450 and N-demethylase activity. 3-Amino-1,2,4-triazole, an inhibitor of the second step in hepatic heme synthesis, prevents the stimulation of hepatic heme synthesis and the induction of P-450 and N-demethylase activity. It is suggested that induction of δ-aminolevulinic acid synthetase leading to increases in hepatic heme synthesis may be the mechanism by which benzpyrene induces cytochrome P-450 and certain hepatic microsomal oxidations.
Evaluation of improved maxillofacial prosthetic materials

Abstract The methods for evaluation of maxillofacial prosthetic materials have been described, and the formulation of plastisols with average test data have been recorded. The Prototype III is the most satisfactory developed for clinical use. These restorations have to be remade quite often for most applications; one year is about the best service life if esthetic results are important. Future research needs to be directed toward longer life and more simplified reproduction.
Preparation and properties of the SrTi1−xFexO3−x2/Ox2 system

Abstract The formula SrTi 1− x Fe x O 3− x 2 O x /2 represents solid solutions of SrTiO3 and SrFeO2.5 where valence compensation is achieved by way of oxygen vacancies, O. Structural and electrical parameters were established over wide ranges of x. Resistivities vary regularly from the insulator SrTiO3 to 8 ohm-cm for SrFeO2.5. Structurally, the perovskite lattice is retained to x = 0.99.
Fabrication of 2-dimensional platinum nanocatalyst arrays by electron beam lithography: ethylene hydrogenation and CO-poisoning reaction studies

Electron beam lithography (EBL) has been used to fabricate platinum nanoparticle arrays in the 20-nm size range on oxide thin films of silica and alumina deposited onto silicon wafers. A combination of characterization techniques (SEM, AFM, XPS, AES) has been used to determine size, spatial arrangement and cleanliness of these fabricated catalysts. Ethylene hydrogenation reaction studies have been carried out over these platinum nanoarrays and have revealed major differences in turnover rates and activation energies of the different nanostructures when clean and when poisoned with carbon monoxide. The oxide–metal interfaces are implicated as important reaction sites that remain active when the metal sites are poisoned by adsorbed carbon monoxide.
Microfabricated Differential Reactor for Heterogeneous Gas Phase Catalyst Testing

Abstract A differential packed-bed reactor microfabricated in silicon is presented for heterogeneous gas phase catalyst testing. A novel cross-flow design achieves uniform flow distribution over a wide (25.5 mm) but shallow (400 μm long × 500 μm deep) catalyst bed to realize differential conversions with sufficient reaction to allow monitoring with conventional analysis techniques. The use of catalyst particles (diameters 53–71 μm) implies that conventional synthesis procedures can be used and experimental results translated to catalysts in macroscopic reactors. A set of shallow microfabricated channels maintains a spatially uniform pressure drop irrespective of variations in catalyst packing. Experiments and finite element simulations confirm the bed is isobaric with even distribution of flow. Quantitative analysis of transport effects indicates the microreactor also suppresses thermal and mass gradients in the catalyst bed. These characteristics make the cross-flow microreactor a useful tool for experiments to obtain kinetics and optimize reaction conditions. Experiments with CO oxidation confirm the ability of the microreactor to obtain kinetic and mechanistic information that compare well with parameters previously determined in macroscale systems. Reactor modeling also indicates that the catalyst bed operates differentially even at total conversions that would be considered large in traditional plug flow reactors, adding to the utility of the cross-flow microreactor as a laboratory tool.
EVALUATION OF MATHEMATICALLY EQUIVALENT TRACKING SYSTEMS.

Abstract : The research reported is concerned principally with the effect upon tracking performance of variation in the mechanical characteristics of a manual control device, with the overall transfer function of the control system held constant. The data indicate that despite 'mathematical equivalence,' or constancy of overall transfer function, computer-generated dynamics do not successfully replace control device dynamics, in terms of the effect upon operator performance. The discrepancy is attributed to the importance of cutaneous, kinesthetic, and proprioceptive feedback. Ancillary research concerning practice effects, aiding ratio, cross-correlational analysis, and scaling of forces is also described. (Author)
Relationship of quality characteristics of peaches (cv. Loring) to maturity

The effect of maturity and ripening on the quality characteristics of Loring peaches was determined. Size, weight, Minolta a values, sucrose, total sugar, soluble solids (SS) and SS/TA ratio of cv. Loring peaches increased significantly with increased degree of maturity of fruit. Firmness, titratable acidity (TA) and delayed light emission (DLE) decreased significantly with increased maturity grade. The fruit of grades 1 and 2 did not attain sensory characteristics similar to tree ripe fruit (grades 6 and 7). The fruit of those grades were less sweet and more sour than grades 3-7. The optimum maturity for harvesting Loring peaches for optimum quality was maturity grade 5.
A mathematical model for the solution mining of primary copper ore: Part I. leaching by oxygen-saturated solution containing no gas bubbles

An unsteady-state, one-dimensional model which simulates the solution mining of a rubblized copper ore body deeply buried below the water table has been developed. Leaching is accomplished by pumping water saturated with oxygen into the bottom of the flooded rubble chimney. The physical processes incorporated in the present model include the axial convective transport of mass and heat, axial dispersion of mass, mass transfer between the bulk fluid and solid surface, and pore diffusion within the ore fragments. The solution withdrawn from the top of the chimney is recycled through the bottom of the chimney, and the temperature of the chimney is allowed to build up by means of the heat generated during leaching. The coupled model equations are solved numerically by an implicit finite-difference method. Model calculations for the leaching process are made for two different modes of operation: (1) constant flow-rate and (2) variable flow-rate of the leach solution during leaching. The calculated results from both modes of operation indicate that thefractional recovery of copper increases with decreasing ore particle size, ore grade, pyrite/chalcopyrite molar ratio, and shape factor. Copper recovery is rather insensitive to the chimney porosity under typical operating conditions.
Massive liver growth in mice induced by systemic interleukin 6 administration

The multifunctional cytokine interleukin 6 (IL-6) is expressed in a wide variety of disease states and pathologic processes. Mice deficient in IL-6 display abnormal and delayed liver regeneration and repair. Currently, IL-6 is thought to influence liver growth indirectly by priming hepatocytes to respond to growth factors such as hepatocyte growth factor (HGF) by inducing expression of HGF and by inhibiting hepatocyte apoptosis, as distinct from the direct mitotic effects of IL-6 on myeloid and other cell types. Here, we show that systemic administration of IL-6 using CHO cell tumors in nude mice results in dramatic hepatomegaly and hepatocyte hyperplasia in the absence of liver injury. Liver mass and liver to body mass ratios increased to 2 to 3 times normal because of proliferation of hepatocytes. Liver growth was associated with high levels of serum IL-6 and with activation of the IL-6-signaling pathway, including increased expression of IL-6 receptor-alpha/gp80, activation of the signal transducer and activator of transcription-3 (STAT-3), and mitogen-activated protein kinase (MAPK/ERK)-signaling pathways and induction of downstream target genes, including c-myc. HGF receptor and transforming growth factor alpha (TGF-alpha)/epidermal growth factor (EGF) receptor activation were decreased in hypertrophied livers, suggesting that IL-6-induced liver growth was independent of these known hepatocyte mitotic pathways. In conclusion, we suggest that IL-6 may function as a direct hepatic mitogen in vivo and, furthermore, that IL-6 warrants closer examination as a potent liver growth factor with potential clinical utility for increasing liver mass following injury.
Teaching with intent: The archaeology of gender

Este ensayo discute la relacion de instruir sobre la expresion politica, especialmente el papel de la critica feminista en el desarrollo de la arqueologia y el lugar de esta critica en la clase. Ce papier aborde la relation de l'enseignement et de l'expression politique, en particulier le role de la critique feministe dans le developpement de l'archeologie et de la place de cette critique dans les salles de classe.
Running on Two or on Four Legs: Which Consumes More Energy?

Disagreement exists over whether man's bipedal form of locomotion evolved as an economical means for covering long distances. There is also some disagreement about the energetic price man had to pay to free his hands. In an investigation of the relative energetic cost of bipedal and quadrupedal locomotion in primates, chimpanzees (Pan troglodytes) and capuchin monkeys (Cebus capucinus) were trained to run on a treadmill either on two or on four legs while their oxygen consumption was being measured. Both primates expend the same amount of energy whether running on two or on four legs. The relative energy cost of bipedal versus quadrupedal running should not be used in arguments about the evolution of bipedal locomotion in man.
The Late Eocene 187Os / 188Os excursion: Chemostratigraphy, cosmic dust flux and the Early Oligocene glaciation

Abstract High resolution records (ca. 100 kyr) of Os isotope composition (187Os / 188Os) in bulk sediments from two tropical Pacific sites (ODP Sites 1218 and 1219) capture the complete Late Eocene 187Os / 188Os excursion and confirm that the Late Eocene 187Os / 188Os minimum, earlier reported by Ravizza and Peucker-Ehrenbrink [Earth Planet. Sci. Lett. 210 (2003) 151–165], is a global feature. Using the astronomically tuned age models available for these sites, it is suggested that the Late Eocene 187Os / 188Os minimum can be placed at 34.5 ± 0.1 Ma in the marine records. In addition, two other distinct features of the 187Os / 188Os excursion that are correlatable among sections are proposed as chemostratigraphic markers which can serve as age control points with a precision of ca. ± 0.1 Myr. We propose a speculative hypothesis that higher cosmic dust flux in the Late Eocene may have contributed to global cooling and Early Oligocene glaciation (Oi-1) by supplying bio-essential trace elements to the oceans and thereby resulting in higher ocean productivity, enhanced burial of organic carbon and draw down of atmospheric CO2. To determine if the hypothesis that enhanced cosmic dust flux in the Late Eocene was a cause for the 187Os / 188Os excursion can be tested by using the paired bulk sediment and leachate Os isotope composition; 187Os / 188Os were also measured in sediment leachates. Results of analyses of leachates are inconsistent between the south Atlantic and the Pacific sites, and therefore do not yield a robust test of this hypothesis. Comparison of 187Os / 188Os records with high resolution benthic foraminiferal δ18O records across the Eocene–Oligocene transition suggests that 187Os flux to the oceans decreased during cooling and ice growth leading to the Oi-1 glaciation, whereas subsequent decay of ice-sheets and deglacial weathering drove seawater 187Os / 188Os to higher values. Although the precise timing and magnitude of these changes in weathering fluxes and their effects on the marine 187Os / 188Os records are obscured by recovery from the Late Eocene 187Os / 188Os excursion, evidence of the global influence of glaciation on supply of Os to the ocean is robust as it has now been documented in both Pacific and Atlantic records.
Macromolecular transport across the superficial layer of articular cartilage.

Abstract Objective To study the role of the superficial layer of articular cartilage in the transport of macromolecular solutes. Design The articular cartilage of intact bovine carpal bones was incubated with 125 I-labeled bovine serum albumin, human IgG, or horse ferritin for 4 hours. Quadruplicate samples were first incubated with polymorphonuclear neutrophil elastase for 30 minutes to remove the outermost layer covering the articular surface. The rates of exchange of each macromolecule from excised tissue explants in the absence of a concentration gradient were measured at six different time points. The results were expressed as the fraction of radioactive protein exiting the cartilage per mm 2 of tissue, or as picomoles of labeled solute per mm 2 . Results Exchange rates correlated well with molecular mass, and no apparent differences were detected between intact and elastase-treated tissues. However, when the results were expressed in terms of the total number of molecules within the tissue, it was apparent that IgG molecules accumulated in the intact cartilage in larger than expected numbers. This finding was not observed in experiments using elastase-treated tissue. Conclusion These observations suggest that the outermost surface layer does not constitute a barrier to the transport of macromolecules into the deeper zones of the tissue. The higher IgG accumulation observed in intact cartilage suggests that the acidic outer layer of cartilage exhibited attractive interactions, probably ionic in nature, with the cationic fraction of IgG. These observations may relate to our previous work demonstrating that the sequestered immune complexes in the superficial zone of articular cartilage in rheumatoid arthritis, and in the antigen-induced arthritis model, are formed because pre-existing antibody normally present in cartilage irreversibly traps antigen within the tissue.
Some postoperative oral observations in congenital heart disease.

Abstract 1. 1. A discussion is given of the observations made in the teeth and surrounding structures as seen in the following conditions: tetralogy of Fallot, coarctation of the aorta, and patent ductus arteriosus after surgery. 2. 2. Postoperatively, the most striking changes were observed in the tetralogy of Fallot. It was found that the cyanosis of the lips, cheeks, gingivae, and buccal mucous membranes was absent. The papillae of the tongue were normal, and no longer as raised, prominent, or extremely reddened as prior to operation. The cyanosis of the tongue was very much less marked. The blood vessels in the inferior surface of the tongue were less prominent. 3. 3. No change was observed in the size and shape of the pulps of the maxillary incisors after operation in coarctation of the aorta. They were still markedly enlarged and funnel-shaped. 4. 4. No observable oral manifestations were noted in patent ductus arteriosus before or after operation.