cssi/SciSciGPT-SciSciNet huggingface dataset:
Computationally efficient design of optimal strategies for controllable damping devices

SUMMARY The development of control strategies for controllable passive dampers — ‘semiactive’ damping devices — is complicated by the nonlinear and dissipative nature of the devices and the nonlinear nature of the closed-loop system with any form of parametric feedback control. Control design for nonlinear systems is often achieved by designing a control for a linearized model since strategies for linear systems are straightforward. One such approach is clipped-optimal control in which the desired damper forces are determined from an optimal controller (e.g., linear quadratic regulator, linear quadratic Gaussian, H2 and H∞), which is designed assuming that the damping devices are fully linear actuators that can exert any forces (dissipative or nondissipative), and a secondary bang–bang controller commands the controllable damper to exert forces as close as possible to the desired forces. However, designs using any linearized model generally result in suboptimal (and sometimes very poor) performance because the linear actuator assumption differs from the actual implementation with a dissipative damping device. Thus, one must generally resort to a large-scale parameter study in which the nonlinear system is simulated many times to determine control strategies that are actually optimal for the nonlinear controlled closed-loop system. This paper demonstrates how an approach developed by the authors, which can reduce the model of a system with local modifications to a lower order set of Volterra integral equations in the modification forces, can significantly decrease the computational burden of a complex control design study for controllable dampers. The approach is first adapted to use a state feedback control with a bang–bang on–off secondary controller. Then, the structural and damping device models are detailed. The optimal semiactive control design is demonstrated via both a parameter study and an optimization algorithm. Numerical examples demonstrate that the approach is effective and, compared with a conventional simulation approach, can reduce computation time by two orders of magnitude. Copyright © 2014 John Wiley & Sons, Ltd.
Quinus ab omni naevo vindicatus

QUINE'S CRITIQUE Quine and his critique Today there appears to be a widespread impression that W. V. Quine's notorious critique of modal logic, based on certain ideas about reference, has been successfully answered. As one writer put it some years ago: “His objections have been dead for a while, even though they have not yet been completely buried.” What is supposed to have killed off the critique? Some would cite the development of a new “possible-worlds” model theory for modal logics in the 1960s; others, the development of new “direct” theories of reference for names in the 1970s. These developments do suggest that Quine's unfriendliness towards any formal logics but the classical, and indifference towards theories of reference for any singular terms but variables, were unfortunate. But in this study I will argue, first, that Quine's more specific criticisms of modal logic have not been refuted by either of the developments cited, and further, that there was much that those who did not share Quine's unfortunate attitudes might have learned about modality and about reference by attention to that critique when it first appeared, so that it was a misfortune for philosophical logic and philosophy of language that early reactions to it were as defensive and uncomprehending as they generally were.
Estimation of required monitoring time for obtaining validation data in enclosed spaces.

Methods for estimating airborne contaminant concentrations at specific locations within enclosed spaces, such as mathematical models and computational fluid dynamics (CFD), often are validated against directly measured concentrations. However, concentration variation with time introduces uncertainty into the measured concentration. Failure to determine monitoring time requirements can lead to errors in quantifying representative concentrations, which are likely to be attributed to errors in the method being validated. In the current study, to obtain the representative concentrations at multiple locations with a direct reading instrument, we used the standard deviation ratio (SDR) method to determine the required minimum monitoring time within a specified precision limit. To demonstrate the use of the SDR approach in constructing precision confidence intervals, tracer gas concentrations at nine sampling locations in an experimental room were measured to obtain population parameters. Three flow rates of 0.9, 3.3 and 5.5 m3 min−1 were employed and contaminant concentrations were measured using a photoionization analyser. Monitoring time requirements varied substantially with location within the room and were strongly dependent upon the flow rate of air through the room. The proposed method would be very useful for industrial hygienists and indoor air researchers who sometimes need to obtain several hundred measured concentrations for validation purposes or to perform tests under repeatable conditions in enclosed spaces. This study also showed that the proposed method can be used to devise efficient indoor monitoring strategies.
Optimal parallel algorithms for forest and term matching

Abstract Forest matching is a fundamental step in solving various problems defined on terms such as term matching . We describe the first optimal speedup parallel algorithm for solving the forest matching problem. Our algorithm runs in time O(log n ) using n log n processors on a CRCW PRAM, given a forest of n nodes as input. We use this algorithm to design the first optimal speedup parallel algorithm for solving the term matching problem. We also extend these algorithms to run on the weaker CREW PRAM with optimal speedup as well. This will involve a simple randomization scheme for simulating concurrent writes through a use of hashing.
Unified solution of security-constrained unit commitment problem using a linear programming methodology

With the advent of open markets trading of power as a commodity, secure operation is an enduring concern of the independent system operator. A comprehensive security-constrained unit commitment (SCUC) methodology to coordinate a secure and economic generation pattern for the day-ahead market is an urgent requirement. An ineffective coordination of electric power transfer over the transmission lines could result in congestion, and inadvertently an outage cause through line overloading. In the current practice, the SCUC is solved by decoupling the cost evaluation aspect from the network security aspect. The primary frequency regulation reserve deployable in a manner after a ( n -1) contingency has not been fully utilised in the present approaches.
Potential and Current Distributions Calculated Across a Quantum Hall Effect Sample at Low and High Currents.

Abstract : The potential and current distributions are calculated across the width of a quantum Hall effect sample for applied currents between 0 microA and 225 microA. For the first time, both a confining potential and a current-induced charge-redistribution potential are used. The confining potential has a parabolic shape, and the charge-redistribution potential is logarithmic. The solution for the sum of the two types of potentials is unique at each current, with no free parameters. For example, the charge-depletion width of the confining potential is determined from a localization experiment by Choi, Tsui, and Alavi, and the spatial extent of the conducting two-dimensional electron gas across the sample width is obtained from the maximum electric field deduced from a high-current breakdown experiment by Cage and Lavine, and from the quantum Hall voltage. The spatial extent has realistic cut-off values at the sample sides; e.g., no current flows within 55 magnetic lengths of the sides for currents less than 215 microA. The calculated potential distributions are in excellent agreement with contactless electro-optic effect laser beam measurements of Fontein et al.
Nuclear Structure and Chromosome Segregation in Drosophila Male Meiosis Depend on the Ubiquitin Ligase dTopors

In many organisms, homolog pairing and synapsis at meiotic prophase depend on interactions between chromosomes and the nuclear membrane. Male Drosophila lack synapsis, but nonetheless, their chromosomes closely associate with the nuclear periphery at prophase I. To explore the functional significance of this association, we characterize mutations in nuclear blebber (nbl), a gene required for both spermatocyte nuclear shape and meiotic chromosome transmission. We demonstrate that nbl corresponds to dtopors, the Drosophila homolog of the mammalian dual ubiquitin/small ubiquitin-related modifier (SUMO) ligase Topors. We show that mutations in dtopors cause abnormalities in lamin localizations, centriole separation, and prophase I chromatin condensation and also cause anaphase I bridges that likely result from unresolved homolog connections. Bridge formation does not require mod(mdg4) in meiosis, suggesting that bridges do not result from misregulation of the male homolog conjunction complex. At the ultrastructural level, we observe disruption of nuclear shape, an uneven perinuclear space, and excess membranous structures. We show that dTopors localizes to the nuclear lamina at prophase, and also transiently to intranuclear foci. As a role of dtopors at gypsy insulator has been reported, we also asked whether these new alleles affected expression of the gypsy-induced mutation ct6 and found that it was unaltered in dtopors homozygotes. Our results indicate that dTopors is required for germline nuclear structure and meiotic chromosome segregation, but in contrast, is not necessary for gypsy insulator function. We suggest that dtopors plays a structural role in spermatocyte lamina that is critical for multiple aspects of meiotic chromosome transmission.
Isotope exchange studies on rabbit liver N-acetyltransferase.

Abstract N -Acetyltransferase from mammalian liver catalyzes the acetylation of isonicotinic acid hydrazide, various sulfonamides and other aromatic amines. Initial velocity and product inhibition studies reported previously indicate that this reaction proceeds according to a simple ping pong BiBi mechanism. It follows that enzymatic acetylation of a drug should consist of two consecutive reactions, the first of which leads to formation of an acetyl-enzyme intermediate and the second to acetylation of the drug with regeneration of the enzyme. In the present study, the existence of these two reactions has been demonstrated by isotope exchange techniques and an acetyl- N -acetyltransferase intermediate capable of transferring acetyl groups to isonicotinic acid hydrazide has been isolated.
A modular neural network architecture for sequential paraphrasing of script-based stories

Sequential recurrent neural networks have been applied to a fairly high-level cognitive task, i.e. paraphrasing script-based stories. Using hierarchically organized modular subnetworks, which are trained separately and in parallel, the complexity of the task is reduced by effectively dividing it into subgoals. The system uses sequential natural language input and output and develops its own I/O representations for the words. The representations are stored in an external global lexicon and are adjusted in the course of training by all four subnetworks simultaneously, according to the FGREP-method. By concatenating a unique identification with the resulting representation, an arbitrary number of instances of the same word type can be created and used in the stories. The system is able to produce a fully expanded paraphrase of the story from only a few sentences, i.e. the unmentioned events are inferred. The word instances are correctly bound to their roles, and simple plausible inferences of the variable content of the story are made in the process. >
Comprehensive analysis of imprinted genes in maize reveals allelic variation for imprinting and limited conservation with other species

In plants, a subset of genes exhibit imprinting in endosperm tissue such that expression is primarily from the maternal or paternal allele. Imprinting may arise as a consequence of mechanisms for silencing of transposons during reproduction, and in some cases imprinted expression of particular genes may provide a selective advantage such that it is conserved across species. Separate mechanisms for the origin of imprinted expression patterns and maintenance of these patterns may result in substantial variation in the targets of imprinting in different species. Here we present deep sequencing of RNAs isolated from reciprocal crosses of four diverse maize genotypes, providing a comprehensive analysis that allows evaluation of imprinting at more than 95% of endosperm-expressed genes. We find that over 500 genes exhibit statistically significant parent-of-origin effects in maize endosperm tissue, but focused our analyses on a subset of these genes that had >90% expression from the maternal allele (69 genes) or from the paternal allele (108 genes) in at least one reciprocal cross. Over 10% of imprinted genes show evidence of allelic variation for imprinting. A comparison of imprinting in maize and rice reveals that 13% of genes with syntenic orthologs in both species exhibit conserved imprinting. Genes that exhibit conserved imprinting between maize and rice have elevated nonsynonymous to synonymous substitution ratios compared with other imprinted genes, suggesting a history of more rapid evolution. Together, these data suggest that imprinting only has functional relevance at a subset of loci that currently exhibit imprinting in maize.
A Hardy space for Fourier integral operators

We introduce a new function space, denoted by H FIO 1 (ℝn), which is preserved by the algebra of Fourier integral operators of order 0 associated to canonical transformations. A subspace of L1 (ℝn), this space in many aspects resembles the real Hardy space of Fefferman-Stein. In particular, we obtain an atomic characterization of H FIO 1 (ℝn). In contrast to the standard Hardy space, these atoms are localized in frequency space as well as in real space.
Nurse practitioners' treatment of febrile infants in Utah: comparison to physician practice nationally.

Purpose To determine nurse practitioners' (NPs') knowledge of published guidelines involving the treatment of infants with fever without a source and to compare the practice of NPs in Utah to physicians nationally. Data Sources Using a comparative descriptive design, a survey was sent to 450 NPs in Utah replicating the methodology of a 1998 survey of physicians. The NPs were asked about their evaluation decisions and management strategies for various ages of infants/toddlers with fever without a source. Conclusions The practice decisions of NPs in Utah and physicians nationally were similar. Family NPs' clinical decisions aligned more closely with family practice medical doctors and pediatric NPs' with pediatricians. Overall, the younger the patient, the more likely were NPs to order labs and antibiotics or to hospitalize/refer to a physician. The fact that management decisions were not based upon existing protocols may account for the practice variation seen among NPs. Implications for Practice Management of a febrile infant is a common clinical scenario for the primary care provider. Although evidence-based protocols exist, the treatment of febrile infants remains controversial. Overall, NPs' evaluation and management of these infants were not shown to differ from physicians. Further studies are needed to determine why clinical guidelines are not being followed.
Young children’s knowledge of names and uses of common tableware

Young children named and described uses of nine kinds of common tableware across four sets that differed in shape and color nested in shape. Using tableware from two sets, some children were trained on conventional names and specific uses of all kinds of the same shape but different colors (within-shape condition) or of all kinds of different shapes and colors (across-shape condition); children in the activation condition saw and talked about the kinds in all four sets. After within- and across-shape training, percentages of appropriate names and labels of uses increased by varying amounts from very low percentages of names given before training and sometimes higher, but still low, percentages of uses. The activation condition did not increase percentages of names, but did increase percentages of uses, but less than for within- and across-shape conditions. These increases and other findings imply that young children can and do abstract sensory invariants/criterial attributes of multidimensional stimuli.
Postcolonial disruptions: Reading the (feminine) baroque in Calixthe Beyala's Tu t'appelleras Tanga

Recently, the baroque has received considerable attention, especially as it relates to contemporary society and certain “neo-baroque” characteristics used to describe the more bizarre aspects of th...
Aeolian and fluvial processes in dryland regions: the need for integrated studies

Aeolian and fluvial processes play a fundamental role in dryland regions of the world and have important environmental and ecological consequences from local to global scales. Although both processes operate over similar spatial and temporal scales and are likely strongly coupled in many dryland systems, aeolian and fluvial processes have traditionally been studied separately, making it difficult to assess their relative importance in drylands, as well as their potential for synergistic interaction. Land degradation by accelerated wind and water erosion is a major problem throughout the world's drylands, and although recent studies suggest that these processes likely interact across broad spatial and temporal scales to amplify the transport of soil resources from and within drylands, many researchers and land managers continue to view them as separate and unrelated processes. Here, we illustrate how aeolian and fluvial sediment transport is coupled at multiple spatial and temporal scales and highlight the need for these interrelated processes to be studied from a more integrated perspective that crosses traditional disciplinary boundaries. Special attention is given to how the growing threat of climate change and land-use disturbance will influence linkages between aeolian and fluvial processes in the future. We also present emerging directions for interdisciplinary needs within the aeolian and fluvial research communities that call for better integration across a broad range of traditional disciplines such as ecology, biogeochemistry, agronomy, and soil conservation. This article is a US Government work and is in the public domain in the USA. Published in 2011 by John Wiley & Sons, Ltd.
Perceptions about Substance Use among Male Adolescents in Juvenile Detention

Although adolescents in juvenile detention represent a vulnerable population who are exposed to situations that foster risk-taking behaviors, few studies have been conducted with detained adolescents to determine their perceptions regarding substance use. Ethnographic interviews and observations were conducted with 20 male adolescents who resided in a large metropolitan area juvenile detention facility, to discover their substance use beliefs and the decisions they make to continue or discontinue substance use or abuse. The participants described how they initiated substance use and said that they had rarely made active decisions about substance use until they were detained. They explained the decisions they made, while they were in detention, to stop or cut down their substance use after release. They talked about the problems they anticipated when they returned home and how they hoped to balance their resolutions with their reputations and obligations. Time-out in juvenile detention may offer nurses the...
Outcomes of Osteochondral Lesions of the Knee Repaired With a Bioabsorbable Device

Purpose: We sought to evaluate the functional and radiographic outcome of osteochondral lesions involving the femoral condyle that were arthroscopically repaired via a bioabsorbable fixation device made of self-reinforced poly-L-lactic acid. Methods: A retrospective clinical and radiographic evaluation of 9 patients (8 male and 1 female) with a mean age of 18 years at the time of surgery was carried out. Of these patients, 8 were diagnosed with osteochondritis dissecans and 1 had a traumatic chondral fracture. All patients underwent arthroscopic repair of a discrete osteochondral lesion involving the femoral condyle with a bioabsorbable fixation implant. All patients were evaluated at a mean of 33 months postoperatively. All patients had preoperative magnetic resonance imaging (MRI) documenting the integrity and location of the fragment. Patients were evaluated at follow-up with a physical examination, Lysholm questionnaire, and repeated MRI with specific cartilage pulse sequencing. Results: At surgery, the mean size of the fragment was 2 × 2 cm. A mean of 4 nails was used in each case (range, 2 to 10). All patients were treated with a postoperative rehabilitation protocol of non–weight-bearing for a minimum of 6 weeks. The mean postoperative Lysholm score was 94 (range, 78 to 100). The outcomes were excellent in 7 patients, good in 1, and fair in 1. After surgery, MRI evaluation of the osteochondral lesion and overlying cartilage was graded as healed in 7 patients and of questionable integrity in 2. Conclusions: This report documents the efficacy of a bioabsorbable nail to internally fix osteochondral lesions. It supports the use of MRI for both preoperative planning and postoperative assessment of fragment healing. Level of Evidence: Level IV, therapeutic case series.
Productivity of public and private investment in developing countries: A broad international perspective

Abstract Using reasonably good data for 1973–1980, 1980–1985 and 1985–1990 for 53 developing countries, fairly standard growth models are estimated to compare the productivity of public investment with that of private investment. The main point noted is that public investment appears more productive than private investment in at least as many instances as suggest the opposite. Much caution is, therefore, urged in making strong claims about the productivity of private investment in developing countries being higher than that of public investment.
Ultraviolet Inactivation and Photoreactivation of Chloroplast Development in Euglena Without Cell Death

SYNOPSIS. Exposure to non-lethal doses of ultraviolet completely inactivates chloroplast development and chlorophyll synthesis in Euglena gracilis var. bacillaris and in the Z strain. Treatment with visible light immediately following UV reverses the inactivation completely. The presence of chloroplasts is not necessary for this inactivation since similar results are obtained with light-grown cells (containing chloroplasts) and dark-grown cells (lacking chloroplasts).
A method to suppress the finite-grid instability in plasma simulations

Abstract A technique for suppressing the finite-grid instability in plasma simulation by jiggling the computation mesh is revisited. Linear dispersion theory suggests a reduction in growth rate of 50% when the mesh is randomly jiggled. With an implicit method, a large time step, and a grid with variable spacing, a nearly complete absence of the instability is observed. Because of its simplicity and low cost, it is suggested the method can be used routinely with variable zoning or adaptive grids to suppress the finite-grid instability.
Endocrine responses in the llama to copulation

Abstract Nine adult female llamas were used to determine the time course for secretion of luteinizing hormone (LH) and estradiol-17β (E2) following a single copulation (average 18 min), and progesterone (P4) during the development of the subsequent luteal phase. Heparinized blood samples were obtained through an indwelling jugular cannula at 15-min intervals for up to 24 h following copulation and then once daily for up to 10 d. Luteinizing hormone, assayed by radioimmunoassay (RIA) using a monoclonal antibody 518B7 against the β subunit of bovine LH, was determined at 15 min intervals for 24 h following copulation. Estradiol-17β was determined by RIA at 4-h intervals following copulation, then daily, while P4 values were determined daily by enzyme immunoassay. A significant increase in LH concentration was observed by 15 min after the onset of copulation, with the peak of the preovulatory surge of LH occurring at 2 h; values were basal by 7 h after copulation. Estradiol-17β values, unchanged through 18 h after copulation, tended to decline at 22 h (24 h, P
Weight Loss Management: A Path Lit Darkly

This article reviews recent research on the prevalence and virulence of obesity as a causal risk factor for mortality and morbidity. The prevailing assumption that obesity, by itself, is a chronic disease or a primary risk factor for health is challenged. A historical perspective is used to analyze the efficacy of various medical and educational approaches that have attempted to alter body size in the pursuit of enhanced physical health. The motivational discrepancies between society's media-induced desire for thinness and the health field's risk reduction approach to weight loss are outlined. Finally, ethical issues are raised in relation to current weight control measures, implications for future educational efforts are discussed, and potential guidelines for future weight management programs are presented.
Functional Signal- and Paradigm-Dependent Linear Relationships between Synaptic Activity and Hemodynamic Responses in Rat Somatosensory Cortex

Linear relationships between synaptic activity and hemodynamic responses are critically dependent on functional signal etiology and paradigm. To investigate these relationships, we simultaneously measured local field potentials (FPs) and optical intrinsic signals in rat somatosensory cortex while delivering a small number of electrical pulses to the hindpaw with varied stimulus intensity, number, and interstimulus interval. We used 570 and 610 nm optical signals to estimate cerebral blood volume (CBV) and oxygenation, respectively. The spatiotemporal evolution patterns and trial-by-trial correlation analyses revealed that CBV-related optical signals have higher fidelity to summed evoked FPs (SigmaFPs) than oxygenation-derived signals. CBV-related signals even correlated with minute SigmaFP fluctuations within trials of the same stimulus condition. Furthermore, hemodynamic signals (CBV and late oxygenation signals) increased linearly with SigmaFP while varying stimulus number, but they exhibited a threshold and steeper gradient while varying stimulus intensity, suggesting insufficiency of the homogeneity property of linear systems and the importance of spatiotemporal coherence of neuronal population activity in hemodynamic response formation. These stimulus paradigm-dependent linear and nonlinear relationships demonstrate that simple subtraction-based analyses of hemodynamic signals produced by complex stimulus paradigms may not reflect a difference in SigmaFPs between paradigms. Functional signal- and paradigm-dependent linearity have potentially profound implications for the interpretation of perfusion-based functional signals.
Synthesis of the calcium transport ATPase of sarcoplasmic reticulum and other muscle proteins during development of muscles cells in vivo and in vitro.

Abstract The effect of medium Ca2+ concentration upon the concentration and the rate of synthesis of muscle proteins was investigated in chicken pectoralis muscle cultures. There is an easily identifiable class of muscle protein which includes the Ca2+-ATPase of sarcoplasmic reticulum, myosin, troponin C, ATP : creatine phosphotransferase, muscle specific actin, tropomyosin 1 and 2, and muscle hemagglutinin, which show a large increase in concentration during normal development. The increased synthesis of these proteins was inhibited, without inhibition of cell proliferation, in culture media of relatively low Ca2+ concentration, 0.05–0.3 mM, where fusion was prevented. Similar medium Ca2+ concentration was required for the expression of all these proteins, suggesting their coordinate regulation. The proteins are denoted as ‘calcium-modulated proteins’. The increased Ca2+ transport activity of sarcoplasmic reticulum in cultured chicken pectoralis muscle cells during development at 1.8 mM medium calcium concentration represents de novo synthesis of the Ca2+ transport ATPase, as shown by immunoprecipitation, active site labeling and direct identification of the Ca2+ transport ATPase on two-dimensional gel electropherograms of whole muscle homogenates. The concentration and the turnover rate of the majority of the muscle proteins is not affected significantly by medium Ca2+ concentration between 0.06 and 1.8 mM. It is proposed that increase in cytoplasmic free Ca2+ concentration during fusion plays a central role in the regulation of the synthesis of calcium-modulated proteins.
Role for the nuclear receptor-binding SET domain protein 1 (NSD1) methyltransferase in coordinating lysine 36 methylation at histone 3 with RNA polymerase II function

The NSD (nuclear receptor-binding SET domain protein) family encodes methyltransferases that are important in multiple aspects of development and disease. Perturbations in NSD family members can lead to Sotos syndrome and Wolf–Hirschhorn syndrome as well as cancers such as acute myeloid leukemia. Previous studies have implicated NSD1 (KMT3B) in transcription and methylation of histone H3 at lysine 36 (H3-K36), but its molecular mechanism in these processes remains largely unknown. Here we describe an NSD1 regulatory network in human cells. We show that NSD1 binds near various promoter elements and regulates multiple genes that appear to have a concerted role in various processes, such as cell growth/cancer, keratin biology, and bone morphogenesis. In particular, we show that NSD1 binding is concentrated upstream of gene targets such as the bone morphogenetic protein 4 (BMP4) and zinc finger protein 36 C3H type-like 1 (ZFP36L1/TPP). NSD1 regulates the levels of the various forms of methylation at H3-K36 primarily, but not exclusively, within the promoter proximal region occupied by NSD1. At BMP4 we find that this reduces the levels of RNAP II recruited to the promoter, suggesting a role for NSD1-dependent methylation in initiation. Interestingly, we also observe that the RNAP II molecules that lie within BMP4 have inappropriate persistence of serine-5 phosphorylation and reduced levels of serine-2 phosphorylation within the C-terminal domain (CTD) of the large subunit of RNAP II. Our findings indicate that NSD1 regulates RNAP II recruitment to BMP4, and failure to do so leads to reduced gene expression and abrogated levels of H3K36Me and CTD phosphorylation.
Upper limits of power law creep of rocks

Abstract At depths below a few kilometers, most rocks probably flow in the steady-state dominantly by diffusion-assisted dislocation creep mechanisms whereby strain rate is proportional to a low power of deviatoric stress. At high stress levels for metals, ceramics and rocks, the power law breaks down (PLB) to some other strain rate-stress functional relationship and this paper explores four methods by which the breakdown stress, σb, may be estimated. For metals, alloys and ceramics, σb ≅ 10−3μ, for non-silicate rocks, σb ≅ 5 × 10−3μ, and for silicates, σb ≅ 10−2μ. For silicates, the low stress exponent power law breaks down at high stresses to an exponential dependence of strain rate upon stress or to a Dorn law, the governing flow mechanisms generally being lattice-resistance controlled dislocation glide and mechanical twinning. PLB breakdown stresses for silicates are nearly strain-rate insensitive and extrapolated values of σb are so high as to suggest that low-temperature, high-stress plasticity may be suppressed entirely in geological deformations. PLB for olivine-rich rocks is discussed in some detail and new three-dimensional deformation mechanism surfaces for wet and dry olivine polycrystals are presented.
Searching for Order in an Orderly World: A Poetic for Post-Machine-Age Managers

This essay explores the difference between order and control, and argues for a new appreciation of the inherent sources of order found in the natural universe. Newer scientific understandings of how natural systems maintain order are contrasted with traditional organizational methods of maintaining order through exerting control. The author suggests that rigidly controlled organizations originate from assumptions based on 17th-century Newtonian images of a machine universe. The laws of entropy, of natural decay and death, apply to machines; resisting entropy requires constant effort and careful controls. But as 20th-century scientists have explored open, dynamic systems, they have observed how order is maintained with very few controls and how order emerges as partners with change. New science concepts from several disciplines are introduced: autopoiesis, quantum physics, self-organizing systems, and chaos theory. These sciences demonstrate a fundamentally new understanding, in which order is identified i...
Approximation by rational modules in Lp and BMO

where each ri(z)~9?(X). Let a= ;(8/2x+ i2/+) be the usual CauchyRiemann operator in the complex plane and let d* = 8 c ii. We note that a function satisfies a*f = 0 in an open set U if and only if f= h + Fk with h and k analytic. A major problem in approximation theory is describing the closure of the rational module 92(X) ~?i in various norms (see [3]). It has been shown in [S] that W(X) gi is dense in C(X), the space of all continuous functions on X, for any compact X when the interior k of X is empty. However, the presence of an interior really complicates the situation. An outstanding open problem is whether S?(X) P, is dense in the space { f~ C(X): J*f= 0 in k} for all compact sets X. For 1 6 p 6 00, let L,P(X) be the closed subspace of Lp(X) which consists of functions analytic in 2. If I/ is any space of functions on X, we denote by [ VJP the closure of V with respect to the LP(X) norm, and we write p = {f: f~ V} where p is the usual Cauchy transform of ,fi In (6) the author proved that [9(.X’) g,], = [W(X) + L:(X)” 1, for all 1 d p < K. using the theory of singular integrals and Schwartz lemma. In this note, we use a somewhat constructuve method to prove the same result for the Lp norms and then extend it to the BMO norm case. To each compact subset X of @ (E lR*) one associates the restrictive spaces BMO(X) = BMO(C)lX z BMO(C))lI(X) and VMO(X) = VMO(@)~,EVMO(C)/J(X), where Z(X)= {~EBMO(C): f’=O a.e. on Xi and J(X)= {~EVMO(@): f=O a.e. on X}. Let [9(X) P,],,, and [g(x) + L,” cm A 1 BMCI be the closure in BMO(X) of 9(X) 9, and a(X) + L,:(X) h, respectively. Holden’s extension theorem [ 1 ] implies that
HEAT FLUX IN LAKE MENDOTA1

The physical processes of heat transfer at the lake’s surface and the internal heat flux are studied for ‘“average” Lake Mendota and for 1958–59. The surface heat budget is determined quantitatively. Details of the internal fluxes of the heat supplied or lost at the surface are discussed, with emphasis on the effects of wind stirring and hydrostatic stability. It is shown that a well-known solution to Fourier’s heat conduction equation suffices to describe many of the features of the internal temperature range and heat flux when an effective thermal diffusivity is introduced. The solution is further used to demonstrate that the internal seiche along the thermocline causing heat flow in bottom sediments may account for 40% of the heat transfer to the hypolimnion.
Effect of a novel pancreatic stent design on short-term pancreatic injury in a canine model.

BACKGROUND AND STUDY AIMS Attempts to address the problem of injury to the pancreas by indwelling pancreatic stents are limited by our lack of knowledge of the pathogenesis of stent-induced injury and its relationship to stent morphology and the duration of stenting. The aim of our study was to evaluate pancreatic injury induced by 1 week of stenting with a 5F indwelling pancreatic stent of novel design, the "wing stent." METHODS Pancreatic stents (5F) were placed surgically in eight dogs; wing stents (WS-5F) were used in four dogs and conventional stents (CS-5F) in another four. Two dogs underwent duodenotomy without stent placement (controls). The pancreas was harvested for microscopy at 1 week. A pathologist who was unaware of the source of the specimens graded the pancreatic injury. RESULTS Although pancreatic injury was observed in both the CS-5F and WS-5F groups after 1 week of indwelling pancreatic stenting, it was considerably less severe in the WS-5F group compared with the CS-5F group (1.01 +/- 0.10 vs. 1.63 +/- 0.14, P < 0.01). All components of pancreatic injury were affected, with the most dramatic differences noted in inflammation, fibrosis, and edema. The differences were most marked in the stented segment ( P < 0.001) and in the upstream segment of the pancreas ( P < 0.05). CONCLUSIONS Indwelling conventional pancreatic stents can cause significant pancreatic injury even when left in place for only 1 week. A wing design can significantly ameliorate stent-induced changes.
Excess volumes for (2-methylbutan-2-ol + n-heptane) and for (cyclopentanol + n-heptane)☆

Abstract Excess volumes measured at 298.15 K in a successive-dilution dilatometer are reported for binary mixtures of (2-methylbutan-2-ol + n -heptane) and of (cyclopentanol + n -heptane). The 2-methylbutan-2-ol mixture exhibits positive excess volumes over the whole mole-fraction range. In contrast to this behavior, the excess volumes of the cyclopentanol mixture show a sigmoid dependence on composition, with positive values limited to lower mole fractions of alkanol than observed previously for (pentan-1-ol + n -heptane). Excess partial molar volumes of the components were calculated for both mixtures, and their values at infinite dilution were estimated. The excess volumes of these mixtures are attributed to a balance between H-bonding, non-specific interactions, and structural effects.
The role of CREB in depression and antidepressant treatment.

Major depressive disorder is a severe clinical problem across the globe, with a lifetime risk of 10%–30% for women and 7%–15% for men. The World Health Organization ranks major depression at the top of the list in terms of disease burden, and this burden is expected to rise in the next decade as the prevalence of the disorder grows. Since the late 1950s, a wide range of antidepressant medications targeting the monoamine systems has been available to alleviate the symptoms of major depressive disorder. Although widely prescribed, such antidepressant medications are accompanied by a delay in effectiveness, as well as varied side effects. Therefore, further characterization of the biological mechanisms behind their function is crucial for the development of new and more effective treatments. One protein that could serve as a convergence point for multiple classes of antidepressant drugs is the transcription factor CREB (cyclic adenosine monophosphate response element binding protein). CREB is upregulated by chronic antidepressant treatment, and increasing CREB levels in rodent models results in antidepressant-like behaviors. Furthermore, postmortem studies indicate that CREB levels are increased in subjects taking antidepressants at the time of death. However, not all antidepressants increase CREB levels and/or activity, and reducing CREB levels in some brain regions also results in antidepressant-like behaviors. This review attempts to consolidate the information relevant to the structure and function of the CREB protein and describe how this relates to the mechanism of antidepressant drugs. Animal models in which CREB function is enhanced, by overexpression of the protein, or reduced, by expression of mutant forms of the protein or through gene deletion experiments, are summarized in terms of identifying a role for CREB in behavioral responses in depression tests that were originally designed to evaluate antidepressant efficacy. Human postmortem and genetic studies that implicate CREB in depression and antidepressant efficacy are also discussed.
Demonstration of JC virus by immunofluorescence in multiple cell types in experimentally infected adult human brain cell cultures

JC virus (JCV)-induced T antigen developed in the nuclei of approximately 50% of adult human brain (AHB) cells infected with JCV. Approximately 10% of these T antigen-positive cells contained glial fibrillary acidic protein (GFAP) and were identified as astrocytes in immunofluorescence studies. About 50% of these T antigen-positive cells bound antiserum to fibronectin on their surface and were identified as fibroblasts. No cells binding antiserum to galactocerebroside (GC), an oligodendrocyte-specific marker, were detected in infected or non-infected AHB cultures. The cell type of AHB that constitutes the remaining 40–50% of T antigen-positive cells that are GFAP-, fibronectin- and GC-negative remains to be determined.
Modelling of ion thruster plume contamination

While the potential problems of spacecraft contamination by the effluents of electric propulsion thrusters have been known for some , t ime, the limitations of ground experiments, and until recently, computational power, have prevented accurate assessments and predictions of spacecraft contamination. We are developing a hybrid plasma particle-incell (PIC) code with a Monte Carlo collision operator to model the plume of an ion thruster and the production of slow charge-exchange (CEX) ions in the plume and their transport back towards the spacecraft. These CEX ions travel back towards the spacecraft and present a contamination hazard. We present preliminary 2-D results of the plume flow structure and show the ion density enhancement around the spacecraft due to the slow CEX ions. &d
False heart-rate feedback and reciprocal inhibition by aversion relief in the treatment of snake avoidance behavior

The purpose of this study was to examine physiological and behavioral data collected using cognitive desensitization technique of treating snake avoidance behavior ( Valins & Ray, 1967 ). The reciprocal inhibition by aversion-relief model was utilized to reinterpret the cognitive desensitization treatment paradigm. The roles of both false and veridical heart-rate feedback were also investigated. Forty subjects who were unable to pick up a snake on a specially designed test of snake intimacy were randomly assigned to one of three experimental treatment procedures and one control group. GSR and EKG responding were measured throughout the experimental treatment procedures. Immediately following the treatment session, subjects were again tested on the snake intimacy test. Subjective fear ratings were also obtained both before and after treatment. Support for the aversion-relief model was found in various aspects of the data. The results indicated that if the cognition, “That stimulus has not affected me internally,” is operating for the snake slides, as suggested by Valins and Ray, it is veridical in nature and based on actual reduced physiological responding. It was also found that false heart rate feedback facilitated the overall aversion-relief treatment process.
Transport-active renal tubular epithelial cells (MDCK and LLC-PK1) in culutre. Prostaglandin biosynthesis and its regulation by peptide hormones and ionophore

Renal tubular epithelial cells isolated from dog and pig kidney (MDCK and LLC-PK1, respectively) transport water and electrolytes in culture. MDCK cells resemble collecting tubule cells by additional, but not all, morphologic and biochemical criteria. It has previously been reported that PGE2 appears to regulate transport activity by MDCK cells as well as their proliferation. We investigated prostaglandin biosynthesis by MDCK and LLC-PK1 cells and assessed the effects of peptide hormones, bradykinin and vasopressin, on the cells' prostaglandin biosynthesis. Thin-layer chromatography of radioactive products released by MDCK cells labelled with octatritiated of [14C] arachidonic acid indicated the presence of materials comigrating with PGE2, PGI2 (detected as 60oxo0PGF1α) and PGF2α, in decreasing order of abundance. Maclofenamate inhibited the biosynthesis of all radioactive peaks comigrating with PGs, thus confirming their identities as product of fatty acid cyclo-oxygenase activity. The chemical identities of [3H] PGE2 and [3H] 6-oxo-PGF1α made by the cells were further confirmed by treatment with KOH. Radioimmunoassay of culture fluids incubated with MDCK cells verified that PGE2 was the most abundant prostaglandin. Tranylcypromine, thought to be a specific inhibitor of prostacyclic synthetase, inhibited PGE2 as well as PGI2 biosynthesis indicating a lack of specificity of the inhibitor. The observation of PGE2 and PGF2α as respectively the most and least abundant prostaglandinds made by MDCK was in disagreement with results from another laboratory in which the reverse order of abundance was found. This suggests the presence of more than one cell line identified as MDCK but having different biochemical properties. Bradykinin stimulated acylhydrolase activity as well as PGE2 and PGI2 biosynthesis in MDCK cells while vasopressin had little or no effect. These results support the hypothesis that bradykinin's natriuretic effects may be mediated by prostaglandinds and that vasopressin is unlikely to acutely stimulate prostaglandin biosynthesis in collecting tubule cells in vivo. Endogenous PGE2 may also regulate the proliferation of MDCK cells in culture. In contrast to MDCK cells, LLC-PK1 cells lacked significant prostaglandin biosynthetic capability as documented by radiometric thin-layer chromatography and radioimmunoassay. This suggests that prostaglandins may have a modulatory rather than an obligatory role in regulating transport activity by tubular epithelial cells.
Rain Forest Exchanges: Industry and Community on an Amazonian Frontier.

Rain Forest Exchanges: Industry and Community on an Amazonian Frontier. William H. Fisher. Washington, DC: Smithsonian Institution Press, 2000. viii. 222 pp., photographs, notes, references, index.
Satellite measurements of chlorophyll distribution during spring 2005 in the California Current

[1] Eight years of satellite data quantify spring 2005 surface chlorophyll-a (chl-a) anomalies in coastal areas of the California Current. Negative anomalies <−1.0 mg m−3 begin in March north of ∼47°N, spread south to 43°N in April and 40°N in May and June 2005, maximum (<−2.0 mg m−3) north of 45°N. Positive chlorophyll anomalies dominate from ∼40°N to 27°N during this period. Strongest negative wind stress and positive coastal surface temperature anomalies are located south of maximum chl-a anomalies, in the region of maximum climatological summer wind stress. Despite the magnitude of these wind anomalies, they remain upwelling-favorable and negative chl-a anomalies are in higher latitude regions of weaker wind anomalies, sufficient however, to prolong winter downwelling, delaying the onset of spring upwelling. In June, winds across the entire region become strongly upwelling favorable and by July, chl-a anomalies switch to positive.