cssi/SciSciGPT-SciSciNet huggingface dataset:
Invention, Innovation, and Wage Inequality in Developed Countries

A growth model that endogenizes skill formation and the skill requirements of invention and innovation is used to analyze developed countries that must invent and innovate vs those that may specialize in innovation. Invention (innovation, respectively) is defined as the creation of (use of) new technologies with the potential to increase (that actually increases) total factor productivity. It is shown that a small innovation specialist will have a larger share of knowledge that is skill saving resulting in lower wage inequality, but with an equal economic growth rate as the invention leader. Specialization in innovation is preferred for all agents in the small country because growth rates of wages for high- and low-skilled workers are higher at the steady state. The large country cannot specialize in innovation, as it cannot rely on significant amounts of invention from abroad. The novel effect helps explain higher returns to skills and the larger increase in wage inequality in the arguably more inventive United States than in other advanced countries in recent decades. The results do not depend on international spillovers from the large to small country (yet still hold in their presence), thereby explaining the skill differential during the information technology revolution, which has been not been characterized by significant, costless spillovers.
Endogenous open space amenities in a locational equilibrium

Little is known about the equilibrium impact of open space protection and growth control policies on the entire metropolitan landscape. This paper is an initial attempt to evaluate open space policies using an empirical approach that incorporates the endogeneity of both privately held open space and land conversion decisions in a locational equilibrium framework. The analysis yields four striking results. First, when one allows for endogenous adjustments in privately held open space, increasing the quantity of land in public preserves may actually lead to a decrease in the total quantity of open space in a metropolitan area. Second, different strategies for spending the same amount of money to purchase open space have markedly different landscape and welfare implications. Third, partial equilibrium welfare calculations are extremely poor predictors of their general equilibrium counterparts. And finally, the analysis suggests that while a growth ring strategy is most effective in reducing total developed acreage in the metropolitan area, this reduction in developed acreage is associated with a large net welfare loss.
CT cholangiography of a choledochocele

Choledochocele is a rare anomaly which has been imaged by a variety of techniques, including CT. A case of choledochocele in an eleven-year-old boy is reported. CT demonstrated a fluid-filled lesion protruding into the lumen of the duodenum and containing stones. CT following oral cholangiogram contrast administration and intravenous sincalide confirmed connection of the cystic lesion with the biliary tree. This is a safe and noninvasive method for the diagnosis of choledochocele.
Trade creation, trade diversion and elastic labor supply

Abstract Welfare effects of a customs union are examined in a two-sector model of a small open economy with elastic labor supply. It is shown that with positive labor supply elasticity and noncomplementarity of leisure and capital intensive good, the conventional results in customs union theory will (will not) hold if the production effect of discriminatory tariff change is weaker (stronger) than its direct leisure effect. However, in the presence of complementarity, or backward bending labor supply, or both, the results become ambiguous, so that trade creation (diversion) might reduce (increase) welfare.
The effects of group interaction and progressive hierarchy presentation on desensitization of test anxiety.

Abstract In order to study the factors of group interaction and progressive hierarchy presentation, as they relate to the desensitization treatment of test anxiety, interaction and non-interaction and progressive and non-progressive hierarchy conditions were differentially applied to various desensitization groups of volunteer college students who had high scores on the Test Anxiety Scale (TAS). In comparison to a nocontact control group (N=8), the experimental Ss as a whole (N = 13) reported more pre-to-post course anxiety reduction on the TAS and achieved a greater increase in grade point average. Students in groups given an opportunity to interact with each other reported greater anxiety reduction on the TAS than those who were not given an opportunity to interact. There were no significant differences between progressive and non-progressive hierarchy groups. Group interaction was discussed as a source of motivation, discrimination learning, and additional desensitization. The necessity of a progressive hierarchy was questioned and the importance of mediational behavior was stressed.
Neuroreceptor changes in the putamen of alcohol abusers.

The purpose of this study was to determine if alcohol abuse affects muscarink cholinergic and benzodiazepine receptors in histologi-cally normal brains obtained at autopsy in a general hospital population. Patients were excluded from this study if they had clinical brain (including Wernicke's) disease, died in coma, had liver disease, significant brain atrophy, or dementia severe enough to require institutionalization. We found that muscarinic cholinergic synaptic receptor density determined with [3H]quinuclidinyl benzilate was decreased by 40% in homogenates of the putamen of 27 alcohol abusers compared with 37 matched nonalcoholic controls. In contrast, receptor densities and affinities of benzodiazepine receptors determined with [3H]flunitrazepam were not significantly different in the two groups. Age and death-autopsy time interval had no significant effects on either wet tissue protein concentrations, yields of protein after centrifugation, or receptor binding. The contributions of age and time interval were each less than 3% of the total variance of protein concentrations and receptor binding. When patients who had received cholinergic, anticholinergic, or benzodiazepine medications before death were excluded or included we observed no significant effects on the final results. Pneumonia, known to be associated with acute hypoxia, and chronic obstructive pulmonary disease, known to be associated with chronic hypoxia, were approximately equally distributed between the two groups and had no significant effects on the results reported here. It is significant that the loss of muscarinic and the sparing of benzodiazepine receptors in the putamen occurs in histologically normal brains in the absence of significant atrophy and gross dementia. It implies that these changes are early in the development of alcoholic encephalopathy. We have previously reponed a decrease of muscarinic and benzodiazepine receptor binding in the frontal cortex and a decrease of muscarinic but not benzodiazepine receptors in the temporal cortex of alcohol abusers. Taken together, these findings suggest that alcohol neurotoxicity does not simply result in a random loss of neurons and/or their associated synapses with their receptors. Instead, different types of receptors are specifically affected or spared, depending upon their location in different brain regions. This suggests the involvement of region- and receptor-specific mechanisms in alcohol toxicity, which then probably results in specific patterns of altered behavior.
How medicine must change.

Let me tell you how pleased and privileged I feel to have been invited here to speak before you, the American Academy of Ophthalmology. And let me at the very outset express my appreciation for all that you do—for your patients, for your profession, for the American Medical Association (AMA). For some time, I've been looking forward to this opportunity to speak before this academy. For many years, the academy and, before your merger, the AmericanAssociationof Ophthalmology have been an important part of the family of medicine. You have an enviable record of attracting members, motivating them to participate in your activities, getting things done politically. And your current long-range planning efforts are exceptional. Yogi Berra once said, "If you don't know where you're going, any road will get you there!" Well, this academy is doing a great job at figuring out where you're going, what road to
Hindlimb suspension reduces muscle regeneration

Exposure of juvenile skeletal muscle to a weightless environment reduces growth and satellite cell mitotic activity. However, the effect of a weightless environment on the satellite cell population during muscle repair remains unknown. Muscle injury was induced in rat soleus muscles using the myotoxic snake venom, notexin. Rats were placed into hindlimb-suspended or weightbearing groups for 10 days following injury. Cellular proliferation during regeneration was evaluated using 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry and image analysis. Hindlimb suspension reduced (P 0.10) on myofiber segments isolated from the soleus muscles of hindlimb-suspended and weightbearing rats following injury. Thus, hindlimb suspension (weightlessness) does not suppress satellite cell mitotic activity in regenerating muscles before myofiber formation, but reduces growth of the newly formed myofibers.
The effect of nutritional factors on the synthesis of staphylococcal penicillinase

Abstract A variety of nutritional factors have been found to exert a marked influence upon the synthesis of penicillinase by staphylococci. Of the amino acids, glutamic acid and tyrosine exerted the greatest stimulatory effect while isoleucine, serine, methionine, and threonine had the greatest inhibitory influence. Of the carbohydrates, maltose raised penicillinase levels threefold over that of glucose. Purines were found to inhibit penicillinase synthesis while pyrimidines did not.
Transduodenal excision of bleeding periampullary endocrine tumor as a bridge to pancreaticoduodenectomy in a Jehovah's Witness patient.

We discuss the case of a Jehovah’s Witness patient who presented with a bleeding endocrine periampul-lary mass. Transduodenal excision of the ampullary mass was successfully performed as a bridge to pan-creaticoduodenectomy in this critically ill patient. The roles of pancreaticoduodenectomy and alternatives to pancreaticoduodenectomy in the emergency setting are reviewed, in particular, for patients who decline transfusion of blood products. The surgical approach to surgery and perioperative anemia in Jehovah’s Witness patients is described. Finally, we reviewed the role of transduodenal excision in the management of ampullary tumors and describe its use as a bridge to pancreaticoduodenectomy in a patient with a ma-lignant neoplasm of the ampulla.
Some bantu ways of talking: The case of kinship vocabularies

Abstract In this paper evidence is adduced from Lingala and Kikongo-Kituba (two Bantu languages of Zaire) to dispute the claims by Bach (1968) and Wierzbicka (1980) that anything which is said in one language can be (faithfully) translated into another language. The paper uses English as the target language and highlights in particular: (1) incongruities which could arise in some translations but do not obtain in the original formulations, (2) shifts from unmarked to marked interpretations of the denotata, and (3) other phenomena pertaining partly to Saussure's “valeur du mot” and to anthropological norms of conduct. According to this author, the old thesis that part of the meanings conveyed in the original language may be lost or distorted in the translation is more tenable than Bach's and Wierzbicka's claims.
From Subject to Citizen: Australian Citizenship in the Twentieth Century

This important, theoretically sophisticated work explores the concepts of liberal democracy, citizenship and rights. Grounded in critical original research, the book examines Australia's political and legal institutions, and traces the history and future of citizenship and the state in Australia. The central theme is that making proofs of belonging to the national culture a precondition of citizenship is inappropriate for a multicultural society such as Australia. This becomes an object lesson for the multicultural regional politics throughout the world.
Classification in Practice: Applying Five Proposed Classification Models to a Sample of Two‐Year Colleges

This concluding chapter illustrates the practical results of the five classification proposals. Each classification model has been applied to a common sample of colleges, and the authors review the key implications of this collective exercise.
Cell surface glycosyltransferases--do they exist?

The presence of glycosyltransferases on surfaces of mammalian cells has been reported by many investigators and a biological role for these enzymes in cell adhesion and cell recognition has been postulated. Critical analysis, however, showed 2 major complications regarding the assay for cell surface glycosyltransferases: (1) hydrolysis of the nucleotide sugar by cell surface enzymes and subsequent intracellular use of the free sugar and (2) loss of cell integrity if trypsinized or EDTA-treated cells were used in suspension asays. We have assayed intact, viable cells in monolayer for cell surface glycosyltransferases using conditions under which intracellular utilization of free sugars generated by hydrolysis of the nucleotide sugar was prevented. Our data demonstrate that the presence of galactosyltransferases on the surface of a variety of cells, including established (normal and virally transformed) as well as nonestablished cells, is unlikely. No evidence for the existence of cell surface fucosyl-and sialyltransferases could be obtained, but our data do not exclude the possibility that low levels of these enzymes are present.
Knowledge‐based organizations

Abstract Organizations will increasingly be regarded as joint human‐computer knowledge processing systems. This perspective has significant implications for the design, management, and success of an organization. A knowledge‐based organization is seen as a society of knowledge workers who are interconnected by a computerized infrastructure. Their work with various distinct types of knowledge is supported in a coordinated, cooperative fashion by the computerized infrastructure. This article identifies the various knowledge types and the building blocks for an infrastructure. It suggests ways in which the blocks can be combined to enhance worker productivity and ways in which the traditional functional areas of management can contribute to the realization of viable knowledge‐based organizations.
Effect of oxide layer on microwave surface resistance of superconducting niobium

We have measured the influence of oxide layers on the surface resistance of niobium resonant cavities at temperatures below 1.4°K. The 8.6 GHz cavity halves were drawn from high purity rolled sheet and electron beam welded together. We measured the resonance quality, Q, of several cavities after alternately removing and growing an oxide layer on the inside surface. Removal was accomplished by absorbing the oxygen into the bulk Nb, at 1100-1200°C, the required temperature having been determined by Auger spectroscopy. Oxide layers were grown by admitting pure oxygen into the cavity at reduced pressure. We found that these oxide layers contribute a residual resistance of \sim10^{-8} \Omega .
Three-dimensional structures for micro-optical mechanical systems in standard CMOS

Ezekiel J. J. Kruglick, Shirish Dainle, Kristofer S. J. PisterUniversity of California at Los AngelesDept. ofElectrical EngineeringLos Angeles, CA 90024, USAABSTRACTA design is presented and tested to build and actuate reflection based three dimensional micro-opto-mechanicalsystems in standard CMOS using only a single maskiess post-processing step. We have built two generations of structuresand actuated them at various frequencies. The initial design uses the various components of CMOS to make a rigid boxstructure with a deflecting mirror. The second generation design uses a bimodal compliant mirror which becomes flat uponbeing pulled against the substrate. Results and photos are presented to show the actuation. Possible developments whichtake advantage ofthe CMOS underlying the structure are discussed.Keywords: micromechanics, optics, CMOS, xenon difluoride, compliant structures, electrostatic actuation1. MICRO-OPTICS AND CMOS
Coke-resistant Ni@SiO2 catalyst for dry reforming of methane

Abstract Nanostructured Ni@SiO2 core–shell catalyst is prepared from nickel oxide nanoparticles by a facile method. Calcination of as-synthesized core–shell nanoparticles creates a micro/meso-porous structure in the amorphous silica shell. The catalytic performance of core–shell catalyst toward dry reforming of methane was first evaluated in a thermogravimeter coupled with a mass spectrometer. Coking is negligible in a reforming period of 40 h on stream at 850 °C, while more than 0.32 gcoke gcat−1 is produced on a commercial Ni-based reforming catalyst in 6.4 h at the same reforming condition. Dry reforming was also performed in a continuous flow, fixed-bed reactor at 750 °C. Characterization of spent catalyst further confirms that Ni@SiO2 catalyst has high coke-resistance for dry reforming. The amount of coke deposited on the core–shell catalyst in 24.5 h is 0.012 gcoke gcat−1.
Characterization of Near-Source Ground Motions with Earthquake Simulations:

We examine the characteristics of long-period near-source ground motions by conducting a sensitivity study with variations in six earthquake source parameters for both a strike-slip fault (M 7.0-7.1) and a thrust fault (M 6.6-7.0). The directivity of the ruptures creates large displacement and velocity pulses in the forward direction. The dynamic displacements close to the fault are comparable to the average slip. The ground motions exhibit the greatest sensitivity to the fault depth with moderate sensitivity to the rupture speed, peak slip rate, and average slip. For strike-slip faults and thrust faults with surface rupture, the maximum ground displacements and velocities occur in the region where the near-source factor from the 1997 Uniform Building Code is the largest. However, for a buried thrust fault the peak ground motions can occur up-dip from this region.
Comparisons of distress in adolescents of cancer patients and controls

Having a family member with cancer has been associated with symptoms of distress. While studies have reported distress in adolescents with a parent with cancer, few have included control groups of adolescents with healthy parents. Adolescents who had at least one parent diagnosed with cancer (n=27) and controls (n=23) completed questionnaires on PTSD, anxiety, depression, cancer risk perceptions, and family environment. Groups did not differ on anxiety and depression, but adolescents with an ill parent perceived their own risk for developing cancer as significantly higher than controls. Controls reported significantly higher levels of intrusive thoughts and avoidance regarding other stressful life events. A positive family environment was correlated with higher anxiety and depression, and expressiveness mediated the relations between family cohesion and anxiety. These preliminary findings suggest that distress reported in previous studies of adolescents with parents with cancer may be due to this transitional period of life.
Electronic quenching of the A1Σ+ state of NaH

Abstract We have measured the rates for quenching of the v = 4 and v = 5 vibrational levels of the A1Σ+ state of sodium hydride using helium, argon, and nitrogen as the quenching gas. The measured rates are compared with earlier results for state-to-state quenching rates. The measured rates for quenching by helium and argon are similar, whereas that for quenching by nitrogen is an order of magnitude higher. In addition, at high nitrogen gas pressures the fluorescence was observed to undergo large scale intensity fluctuations. It is suggested that this may be due to a chemical rather than a physical mechanism.
Hydrogenation or recovery of acetylene: An economic comparison

Abstract Higher hydrocarbon prices have affected the profitability of the recovery or hydrogenation of C 2 -acetylenes from an olefins plant. A review of the economics of these processes therefore seems appropriate. When acetylene production is low and the product has little value, the preferred method is hydrogenation. Furthermore, scattered production makes the marketability problematic. The recovery of acetylene is, however, a really low cost production process. Consequently, the majority of the demand for petrochemical use of acetylene should be satisfied from this source. The main objective of the article is to show the attractiveness of this process.
Biology, distribution, and taxonomy of billbug turf pests (Coleoptera: Curculionidae).

The seasonal distributions and biology of four species of billbug on New Jersey turfs during 1986 and 1987 were examined; Sphenophorus parvulus Gyllenhal, a common pest of turfgrass, and three additional species, S. venatus s.l. (Say), S. minimus Hart, and S. inaequalis (Say), that had previously been overlooked as pests of cool-season turfgrasses in New Jersey. Linear pitfall trap collections of adults indicated: (1) a nearly equal overall abundance of the four species, (2) greater activity of S. inaequalis in the early spring and autumn, and (3) continued activity of S. venatus through the summer. The abundance of S. venatus adults throughout the summer, and continuous egg laying of all four species through August suggested a partial second generation. Larvae of all four species were found damaging cool-season turfgrasses during July. Laboratory-rearing work found little difference in the number of days for egg hatching and pupation, but a longer larval period for S. venatus . To facilitate identification and study by turfgrass specialists, an illustrated key to eight known billbug turf pests is provided and their geographic distributions in the United States are reviewed.
Finite deformation effects in homogeneous and interfacial fracture

Abstract This paper summarizes recent results of asymptotic, numerical and experimental investigations of some nonlinear effects on the mechanics of fracture in homogeneous and bimaterial sheets of a particular class of hyperelastic incompressible materials. The problem is analysed within the framework of the finite strain theory of plane stress. Material induced nonlinearities are included through the use of the generalized neo-Hookean model which is characterized by three parameters which determine the small strain, “yielding” and “hardening” responses of the component(s). The structure of the near-tip stress and deformation fields is described and compared to a full-field finite element investigation. The consequences of the local results on the propagation behavior of a crack under general in-plane loading are outlined in the special case of a homogeneous sheet. The analytical results are corroborated by experimental observations obtained on natural rubber sheets.
The computerization of environmental design

Abstract Across North America, the need for planning and design to address emerging environmental and development problems is evident to all observers. Landscape architects, planners and architects often have the skills to act on the complex information affecting the development and protection of urban, suburban and rural environments. Creatively these professions generate recommendations for change which can improve the world that our children will inherit.
Structures for interacting composite fermions: Stripes, bubbles, and fractional quantum Hall effect

Much of the present day qualitative phenomenology of the fractional quantum Hall effect can be understood by neglecting the interactions between composite fermions altogether. For example, the fractional quantum Hall effect at $\ensuremath{\nu}=n/(2\mathrm{pn}\ifmmode\pm\else\textpm\fi{}1)$ corresponds to filled composite-fermion Landau levels, and the compressible state at $\ensuremath{\nu}=1/2p$ to the Fermi sea of composite fermions. Away from these filling factors, the residual interactions between composite fermions will determine the nature of the ground state. In this paper, a model is constructed for the residual interaction between composite fermions, and various possible states are considered in a variational approach. Our study suggests the formation of composite-fermion stripes, bubble crystals, as well as fractional quantum Hall states for appropriate situations.
The effect of inlet velocity distribution and magnitude on in-cylinder turbulence intensity and burn rate ― model versus experiment

Influence de l'amplitude et de la distribution des vitesses a l'admission sur l'intensite de la turbulence dans les cylindres et le taux de combustion dans un moteur. Comparaison entre theorie et experience
The electronic properties and control of semiconductor interfaces

Abstract Much progress has been made towards the understanding and elimination of the Fermi level pinning problem at compound semiconductor surfaces and interfaces. This progress includes the discovery of several new techniques for reducing and controlling the surface state density and the achievement of metal work function dominated barrier heights at metal/(100) GaAs interfaces. This paper will review this work and the relevance of various Fermi level pinning theories to these results.
Metastatic Cancer to the Heart Review of the Literature and Report of 127 Cases

A review of the literature of metastatic cancer to the heart is presented, and a new classification offered. Autopsy data of The New York Hospital have been analyzed. In the 7-year period, 1947 to 1953, in 694 deaths from cancer, an over-all incidence of 18.3 per cent (127 cases) of metastases to the heart was observed. In a group of 169 cases of lymphoma, leukemia, and myeloma, there was an incidence of 36 per cent (61 cases) of metastases to the heart. In the remaining 525 cases, there was an incidence of 12.6 per cent (66 cases) of metastases to the heart. In 61 of these, gross lesions were present, an incidence of 11.6 per cent (61 cases) of gross metastases to the heart. These figures are comparable to those reported in other series.
CAUDATE, CORTICAL, HIPPOCAMPAL AND DORSAL THALAMIC LESIONS IN RATS: ALTERNATION AND HEBB-WILLIAMS MAZE PERFORMANCE

Abstract Rats with lesions of caudate nucleus, of anterior cortex, of posterior cortex, of dorsal hippocampus, of ventral hippocampus or of dorsomedial thalamic structures were trained on a two-bar alternation task and in a Hebb-Williams maze. The experiments had the following principal aims: (1) to further analyze the alternation deficit previously found to follow caudate lesions; (2) to determine whether those neural structures necessary for alternation performance in the monkey, viz., frontal granular cortex, hippocampus and caudate nucleus are also necessary for alternation in the rat and (3) to test the hypothesis that Lashley's findings of increasingly deficient maze performance with increasing size of cortical lesion might be ascribed, at least partially, to increasing encroachment on an anterior cortical region critical for alternation and a posterior cortical region critical for visually guided behavior. We found that alternation was impaired by caudate lesions, by hippocampal lesions, by anterior cortex lesions and by thalamic lesions that included the dorsomedial nucleus. By contrast, Hebb-Williams maze performance was only impaired by posterior cortex lesions, by lesions that included the lateral geniculate bodies and by large medial thalamic lesions. The alternation deficit could not be accounted for in terms of changes in activity level, motivation, memory or response perseveration. As in the monkey, integrity of the caudate nucleus, the cortical projection of the dorsomedial nucleus and the hippocampus appear necessary for normal alternation performance. Finally, the present results support Hunter's interpretation that Lashley's “mass action” results may be attributed to progressive enroachment on specific “critical” regions.
The “Green Revolution” in Recent Development Experience

HE TERM "green revolution" is now familiar to everyone with more than a passing interest in economic development. The Mexican wheat varieties and the IRRI rice varieties were accorded miracle status by the media as they were rapidly adopted in a number of Asian and African countries after 1965. Their initial promise sparked food self-sufficiency drives in several countries. By 1970 the adoption of these improved, high yielding varieties was credited with providing a realistic basis for sustained productivity gains in LDC agriculture. That promise has turned out to be short-lived, however. The optimism that existed three years ago has all but vanished. The adoption of high yielding varieties has fallen short of expectations, and the abnormally poor weather of the past two years has produced serious food shortages throughout the world. The green revolution "episode" has been subject to numerous evaluations (Willet [8], Barker [1]). Most prior evaluations have made comparative assessments of production and resource utilization between high yielding rice or wheat varietal technology and local or native varietal technology. Dozens of studies have reported very significant cost advantages for the high yielding varietal technology. These studies, however, are all quite local in nature, and in almost all cases, are based on farm data from regions of early adoption of the high yielding varieties. They cannot be used to assess the relative advantage of high yielding varieties over the entire rice or wheat producing regions of the countries where they have been adopted. This paper develops a methodology for assessing the relative advantage of the high yielding varieties in large producing regions and reports estimates of their contribution to aggregate production in Asia and North Africa. A simple specification based on the supposition that real productivity gains in the region were exclusively associated with the adoption of high yielding varieties is first developed. It is rejected in favor of a somewhat richer specification which explicitly considers the contribution of indigenous or national agricultural research activities to productivity gains.
Low energy electron collision phenomena in HgBr2 and CH3HgBr relevant to discharge pumped mercury bromide lasers

Abstract Dissociative excitation of HgBr radical in the B-state has been observed as a result of collisions of low energy electrons with HgBr 2 and CH 3 HgBr molecules. By using the most intense band of HgBr (B, ν ′ = 0-X, ν ″ = 22) transition at 502 nm, emission cross sections have been measured in the electron energy range 1–100 eV. The threshold electron energy for the observation of (B-X) band system has been determined to be 6.5 and 7.0 eV for HgBr 2 and CH 3 HgBr molecules, respectively. These energies are in good agreement with the values previously reported by other investigators.
Analysis of microtubule dynamics using growth curve models

Microtubules are part of the structural network within a cell's cytoplasm, providing structural support as well as taking part in many of the cellular processes. A large body of data provide evidence that dynamics of microtubules in a cell is reponsible for the performance of many critical cellular functions such as cell division. In this article, we study the effect of four different isoforms of a protein tau on microtubule dynamics using growth curve models. The results show that a linear growth curve model is sufficient to explain the data. Moreover, we find that a mutated version of a 3-repeat tau protein has a similar effect as a 4-repeat tau protein on microtubule dynamics. The latter findings conform with the biological understanding of the effect of the protein tau on microtubule dynamics.
Additivity and effective charge studies with light projectiles and target gases of CH4, CO2, He, Ne, Ar, Kr, Xe, Cl2 and Br2

Abstract The stopping powers of CH 4 , CO 2 , Cl 2 , and Br 2 for light projectiles have been analyzed in terms of modified Bethe-Bloch stopping power theory in order to extract mean excitation energies ( I ) and Barkas-effect parameters ( b ) and effective charge parameters for low projectile velocities. Recommended values of ( I , b ) are (46 eV, 1.3) for CH 4 , (90 eV, 2.4) for CO 2 , (199 eV, 1.6) for Cl 2 , and (492 eV, 1.1) for Br 2 . The I -values for compounds lie about 10% (CH 4 ) and 3% (CO 2 ) above additivity-based predictions. The stopping powers of He, Ne, Ar, Kr and Xe were similarly analyzed, but solely for extraction of effective charge parameters valid at low projectile velocities.
The Formation of Monomeric Products from Lignin by the Action of Ammonium Sulfide

Abstract Acetoguaiacone and propioguaiacone were found to be the dominant lignin monomeric products (molar ratio 1.3 to 1) from the spent liquor of hemlock pulped with ammonium sulfide/methanol/water. The combined amounts of the ketones were as high as 3.5% based on wood. This is higher than reported monomer quantities from any other pulping process. The model compounds, guaiacyl glycerol β-(2-methoxyphenyl) ether and coniferyl alcohol, also produced aceto- and propioguaiacone, upon ammonium sulfide treatment at 180°C. The molar conversion to these two ketones was more than 50% in both cases. It was, therefore, concluded that uncondensed β-0-4 lignol structures were the primary lignin precursors of the ketones, and coniferyl alcohol was an intermediate in this conversion. Studies using coniferyl alcohol and wood meal were also conducted at 140°C. An alpha carbonyl intermediate was found which primarily formed propioguaiacone.
Solid-State NMR Structures of Phospholamban or Sarcolipin Bound to Calcium ATPase (SERCA) Reveal the Mode of Inhibition

Sarco(endo)plasmic reticulum calcium ATPase (SERCA) transports Ca2+ ions against a concentration gradient from cytoplasm to sarcoplasmic reticulum, initiating muscle relaxation. SERCA activity is regulated by two single-span membrane proteins: phospholamban (PLN) or sarcolipin (SLN). Although the recent crystal structures offered a prime view of these complexes (SERCA/SLN and SERCA/PLN), the mechanism of regulation is still unknown. Here, we used a combination of oriented and magic angle spinning (MAS) solid-state NMR spectroscopy to gain atomistic level insights into the mechanism of regulation of SERCA by both PLN and SLN in fully hydrated lipid bilayer membranes.To map protein-protein interactions within lipid membranes, we designed innovative labeling strategies involving various combinations of isotopic labeling schemes, paramagnetic probes, and thioalkylation of SERCA's cysteines. The restraints obtained from the experimental data were used to model the complexes which were further refined using restrained molecular dynamics simulations in explicit lipid bilayers. The structures of SERCA in complex with PLN or SLN provide a detailed view of the binding interface and shed light on the mechanism of SERCA regulation (i.e., inhibition and activation). Knowledge of the biophysical basis of SERCA regulation offers unprecedented opportunity for the rational design of the mutants for gene therapy. We expect the approach and methods used by us to be generally applicable for mapping protein-protein interactions in membrane protein complexes larger than 100 kDa, which are typically inaccessible to other experimental methods.
Normalization of left ventricular size and systolic function after diagnosis of pediatric dilated cardiomyopathy

cardiac transplantation. However, data regarding kidney growth after heart transplant in children is lacking. We evaluated the renal growth in infant ( 1 year of age) heart transplant recipients followed at the University of Minnesota. Annual renal ultrasounds were obtained at follow-up. Z scores of kidney size for age and height were calculated based on standard growth curves. There were 19 infant transplant recipients from 1986 to 2000, of whom 15 survived past 1 year of age (12 hypoplastic left heart syndrome, 2 dilated cardiomyopathy, 1 critical aortic stenosis). Median age at transplant was 0.19 0.14 years. Median follow-up was 4.5 (range: 1.4-15.3) years. At follow-up, 2041% of patients had renal size smaller than 2 standard deviations (SD) from the mean predicted for age, however, kidney dimensions were within 2 SD of those predicted for height (table). Treatment with cyclosporine versus FK506 correlated with smaller renal size adjusted for both height (p 0.05; z score: -1 0.6 vs 0.5 0.6) and age (p 0.01; z score ; -1.8 /-0.7 vs -1.2 /-0.7). GFR, creatinine levels, hypertension, history of rejection and treatment with prednisone did not correlate with kidney size. In conclusion, infant heart transplant recipients demonstrate renal size for height within 2 SD of normal, although they tend to have smaller kidneys for age. Treatment with cyclosporin is associated with smaller renal size compared to FK-506. Longer follow-up will determine if renal size is a predictor for late renal failure in children after heart transplantation in infants.
The effect of lipid supplements on ruminal bacteria in continuous culture fermenters varies with the fatty acid composition

A single flow continuous culture fermenter system was used in this study to investigate the influence of dietary lipid supplements varying in their fatty acid content on the DNA concentration of selected rumen bacteria. Four continuous culture fermenters were used in a 4 × 4 Latin square design with four periods of 10 d each. Treatment diets were fed at 45 g/d (DM basis) in three equal portions during the day. The diets were: 1) control (CON), 2) control with animal fat source (SAT), 3) control with soybean oil (SBO), and 4) control with fish oil (FO). Lipid supplements were added at 3% of diet DM. The concentrations of total volatile fatty acids and acetate were not affected (P>0.05) by lipid supplements. Concentrations of propionate, iso-butyrate, valerate and iso-valerate were highest (P 0.05) for all diets. The DNA concentrations of Butyrivibrio fibrisolvens and Ruminococcus albus in fermenters were lowest (P 0.05) among the other treatment diets. Selenomonas ruminantium DNA concentration in fermenters was highest (P<0.05) with the FO diet. In conclusion, SBO had no effect on bacterial DNA concentrations tested in this study and the VA accumulation in the rumen observed on the FO diet may be due in part to FO influence on B. fibrisolvens, R. albus, and S. ruminantium.
The COP9 Signalosome Promotes Degradation of Cyclin E during Early Drosophila Oogenesis

Abstract The COP9 signalosome (CSN) is an eight-subunit complex that regulates multiple signaling and cell cycle pathways. Here we link the CSN to the degradation of Cyclin E, which promotes the G1-S transition in the cell cycle and then is rapidly degraded by the ubiquitin-proteasome pathway. Using CSN4 and CSN5/Jab1 mutants, we show that the CSN acts during Drosophila oogenesis to remove Nedd8 from Cullin1, a subunit of the SCF ubiquitin ligase. Overexpression of Cyclin E causes similar defects as mutations in CSN or SCF Ago subunits: extra divisions or, in contrast, cell cycle arrest and polyploidy. Because the phenotypes are so similar and because CSN and Cyclin E mutations reciprocally suppress each other, Cyclin E appears to be the major target of the CSN during early oogenesis. Genetic interactions among CSN, SCF, and proteasome subunits further confirm CSN involvement in ubiquitin-mediated Cyclin E degradation.
Ion bombardment of alkali halides, V: Particle track effects

Abstract Samples of nominally pure single crystal KCI were irradiated by H, H2, He, C and N positive ions in the energy range 0–2 MeV. The growth of F-type centers was recorded as a function of ion fluence. Depth profiles of damage by H and He ions were constructed, and it was found that the damage profile does not follow the stopping power as a function of penetration depth in the target. Determinations of damage track radii, based on the data, were done, and found to be on the order of 10 A. Comparisons of defect production by H2 with H at the same fluences of nuclei and the same energy per mass showed at low energies more defects by H than by H2, the difference attributable to track overlap.
A direct translator from neutral model format to the SPARK simulation environment

Abstract The neutral model format (NMF) provides generic, machine-readable descriptions of equation-based component models of a physical system in a building description. It is intended to allow model interchange between different simulation environments. The simulation problem analysis and research kernel (SPARK) is a simulation environment that generates source and executable code for solving non-linear differential-algebraic equation systems. It is intended to automate the generation of modular, easy to maintain simulation programs. The goal is to generate simulation code automatically from NMF models transparently to the user. A translator achieving this goal is described here, which transforms NMF syntax into SPARK syntax using LEX and YACC for parsing and numerical inversion techniques generating SPARK code. Thus the practicality of NMF as a common description language for building simulation is demonstrated for the case of a simulation environment developed independently from NMF. The purpose of this paper is to give an account of the experience of building a translator from a general model representation format (NMF) to a particular simulation environment. We first present the NMF format, then the SPARK building simulation environment. Then the 1st translator from NMF to SPARK via a computer algebra system is presented, along with examples. That translator being too circuitous, a newer and direct translator is then presented, along with practical examples. Thus are demonstrated the usefulness of the NMF concept and the methodology for building a translator from it to an independently developed simulation environment for building science.
Interactive software architecture design with modeling & simulation

Due to the increasing complexity of real world problems, it is costly and difficult to evaluate todays software-intensive systems. This paper explores component interaction pattern, and provides a set of methodologies for specifying, verifying, and validating (by simulation) system temporal behavior, with the aim of validating software design iteratively at design and development time. The methods combine such components and technologies as UML, XMI, database, model checking, and simulation.
Resistance to the Flow of Fluids Through Simple and Complex Porous Media Whose Matrices Are Composed of Randomly Packed Spheres

Les milieux «simples» sont composes de spheres de meme diametre tandis que les milieux «complexes» sont composes de spheres de diametres differents. Determination des domaines de validite de la loi de Darcy
Estradiol 17β-dehydrogenase and 20α-hydroxysteroid dehydrogenase from human placental cytosol: one enzyme with two activities?

Abstract The soluble enzyme estradiol 17β-dehydrogenase (17β-ED) from human term placental cytosol is reported to be a stereospecific oxidoreductase for estrogen substrates. A published purification scheme (heat treatment and affinity chromatography) yielded a homogeneous protein which had the reported characteristics of pure 17β-ED and also had 20α-hydroxysteroid dehydrogenase (20α-HSD) activity. Spectrophotometric assay when the buffer contained albumin, 8 mg/ml, masked the 20α-HSD activity observed in albumin-free conditions and may explain why this bifunctional activity has gone unrecognized. In human placenta, one enzyme may catalyze stereospecific oxidation/reduction of both estrogen and progesterone.
Daily Profiles of N‐Acetyltransferase Measured at a Single Time in Rat Pineal Glands, Retinas, and Harderian Glands

Serotonin N-acetyltransferase activity (NAT) exhibited a daily cycle in light:dark (LD) 14:10 when it was measured in pineal glands taken from rats killed at a sequence of time points. The ratio of peak subjective night NAT to minimum subjective day NAT was 10.9/0.3 nmol per pineal gland per hour. When the rats were placed in constant dark the rhythm persisted (8.2/0.02). When the rats were placed in constant light the rhythm persisted with markedly attenuated amplitude (0.6/0.02). We also measured NAT profiles in rat pineal glands, Harderian glands, and retinas with alternative methods. We kept rats on six LD 14:10 light-dark cycles with lights-out beginning at midnight, 2 AM, 4 AM, 6 AM, 8 AM, or 10 AM and killing all the rats at one time point, 10 AM. We examined the NAT time profiles 4, 8, and 11 days following placement of the rats in the phase-shifted cycles. In addition, we measured the NAT profile in LD 2:22 and LD 22:2 by keeping the rats on twelve cycles for 11 days and killing all the rats at one time. Pineal NAT exhibited a rhythm in all the cycles: peak-dark/nadir-light values (nmol product per gland per hour) were 15.6/0.1 in LD 14:10, controls killed at successive time points. The ratios for the profiles obtained using the one time point procedure were 16.7/0.1 in LD 14:10 8.5/0.2 in LD 22.2, and 12.9/0.2 in LD 2.22. Increasing the photoperiod reduced the time to the NAT peak. In LD 14:10, Harderian NAT was 31–39 nmol per gland per hour but the peak/ nadir radio was only 1.2; retinal NAT was low (0.2–0.7 nmol per retina per hour) and had only a 3.5-fold peak/nadir ratio.
Portal vein thrombi after restorative proctocolectomy.

Abstract Background. Restorative proctocolectomy (RP) has been the surgical procedure of choice for surgical management of mucosal ulcerative colitis since 1978. This study was undertaken to investigate the clinical presentation and implications of portal vein thrombi (PVT). Methods. We reviewed all patients undergoing RP in our institution in the 4 years from January 1997 to December 2000. As the diagnosis of PVT was made on computed tomography (CT) scan in all cases, we confined our incidence estimate to those patients having an abdominal CT scan postoperatively. All scans were reviewed by an experienced radiologist. Patient demographics, symptoms, and clinical course were recorded. Results. A total of 702 patients underwent RP, of whom 94 had a CT scan within the postoperative period. PVT was diagnosed in 42 of the 94 patients (45%). PVT was diagnosed at initial reading of the scan in 11 patients, and on review in 31. The indications for CT scan included abdominal pain, fever, leukocytosis, and delayed bowel function. Septic complications of RP caused these symptoms and signs in 45 patients, 20 of whom had PVT. Twenty-two patients were found to have had PVT without evidence of any septic source. Conclusion. PVT can be found in a high proportion of patients undergoing abdominal CT scan after RP. It is often associated with pain, fever, nausea vomiting, tenderness, and leukocytosis. This study shows that PVT subtle enough to go undiagnosed has no serious consequences, even when not treated. Also, patients treated with anticoagulation recover completely. Surgery 2002;132:655-62.
Retention and imprint properties of ferroelectric thin films

The retention and imprint properties of ferroelectric Pb(Zr 0.53 Ti 0.47 )O 3 (PZT) and SrBl 2 Ta 2 O 9 (SBT) thin films are studied. A simple characterization technique which consists of four measurement pulses is used to differentiate the retention and imprint effects. The high concentration of oxygen vacancies in PZT capacitors results in longer screening lengths and higher depolarization fields that worsen retention properties. A c-axis preferred oriented SBT thin film deposited on Pt(100)/MgO(100) substrate contains a higher concentration of 180° domains and results in better retention properties due to the minimum ferroelastic effect. Ferroelectric SBT thin films with symmetric P-E hysteresis loops are chosen to study the imprint effect. The imprint process changes the symmetry of P-E hysteresis loop, which indicates the imprint process builds up an internal field within the ferroelectric thin films. Electrical charges trapped at electrode-ferroelectric interfaces during the imprint stress are responsible for internal field build-up and screen the spontaneous polarization internally.