cssi/SciSciGPT-SciSciNet huggingface dataset:
High time-resolution sprite imaging: observations and implications

Sprites are large scale manifestations of electrical streamers triggered in the upper atmosphere by lightning in an underlying thunderstorm. Imaging of sprites at 10 000 frames per second has provided new insights into their spatial and temporal development. In this paper we discuss the experimental protocols that have been developed for performing high-speed observations of sprites and some new observations that have been obtained of relevance to laboratory experiments. Downward tendrils and upward branches, so characteristic in video recordings, are shown to be formed by very fast streamer heads with velocities up to half the speed of light. The streamer heads are spatially small, ~100 m or less, but very bright with emission rates up to ~1024 photons s−1. The sprite onset begins with a downward streamer. Then, in some sprites, at a little later time and from a lower altitude upward moving streamer heads may also appear. If there are no upward streamers the sprite would be classified as a 'C-sprite'; with both downward and upward streamers it would be a 'carrot sprite'. The optical emissions are primarily from the neutral molecular nitrogen first positive bands emitting in the near-infrared, but there are also blue emissions assumed to be from second positive bands of molecular nitrogen and from first negative bands of nitrogen ions. The streamer heads are observed at times to split into several streamer heads. This process appears to be more frequent in the core of larger sprites.
Self-Determination: The New Phase

Can two or more self-differentiating culture-groups coexist within a single political structure? The question may well seem clearly settled by the overwhelming factual evidence of contemporary international politics, for it is indeed a truism that political and ethnic borders seldom coincide. Thus, the very existence of a host of multinational states, including such a time-tested example as the Soviet Union, would appear to document an affirmative answer. On the other hand, a recent spate of political unrest within such geographically diverse and historically unrelated states as, inter aliay Canada, Guyana, India, Uganda, Belgium, the Sudan, Burma, Yugoslavia, Cyprus, Rwanda, the United Kingdom, and Iraq, focuses attention on the common root cause of intrastate yet international conflict and again brings into question the assumptions of the multinational state.
A Dimensionless Number for the Contact Line Evaporative Heat Sink

The main driving force for flow in very thin films can be the gradient in the van der Waals force. This phenomenon was used by Wayner et al. (1976) to develop an equation for the interline heat transfer coefficient of an evaporating wetting film. Buried in this development is a dimensionless group that can enhance, when properly viewed, the understanding of the evaporation process in the contact line region where the film thickness becomes vanishingly thin. This process is crucial in systems that rely on heat transfer in ultrathin films such as evaporating drops on solid surfaces and evaporating menisci in heat pipes. Herein, the authors discuss the significance and use of this dimensionless contact line heat sink number.
Gestation-related and betamethasone-induced changes in 11β-hydroxysteroid dehydrogenase types 1 and 2 in the baboon placenta

Abstract Objective: We determined developmental and labor-related changes in 11β-hydroxysteroid (HSD) 1 and 2 expression in baboon placentas during the final third of gestation and labor. We examined whether maternal glucocorticoid administration alters placental 11β-HSD 2 expression. Study Design: Maternal and fetal plasma cortisol concentrations were measured in five animals. Types 1 and 2 11β-HSD messenger RNA (mRNA) and protein in placentas obtained at 121 to 185 days' gestation (dGA, term approximately 185 dGA, n=16), during labor between 141 and 193 dGA (n = 8), and after maternal administration of four doses of 87.5 μg/kg betamethasone (n = 5) at 12-hour intervals at 121 to 135 dGA were analyzed by Northern and Western blot. Results: Cortisol levels were higher in maternal plasma than fetal (4-fold, P P P Conclusions: The late-gestation baboon maternal plasma cortisol concentration is four times the fetal plasma concentration. Decreased placental 11β-HSD 2 may enhance maternal cortisol passage to the fetus at the end of gestation, thereby contributing to cortisol-mediated changes within the placenta and cortisol in fetal plasma at this stage of fetal development. The positive effect of betamethasone on placental 11β-HSD 2 induction further suggests an ability of the placenta to regulate glucocorticoid transfer in the presence of elevated maternal glucocorticoid. (Am J Obstet Gynecol 2003;188:13-21.)
Effects of equilibrium H-bond distance and angle changes on Raman intensities from water

The H-bond energy dispersion over the inhomogeneously broadened OD stretching contour from dilute HDO in H(2)O was determined from absolute Raman intensities; it displays a large minimum near omega=2440 cm(-1) from short, strong H bonds (in agreement with the peak omega from lda ice) and a large maximum near 2650-2675 cm(-1) due to extremely weak or broken H bonds (in agreement with the peak omega from dense, supercritical HDO in H(2)O, 0.9 g/cm(3), 673 K). The difference between extrema is the maximum H-bond DeltaE, 5100+/-500 cal/mol, in excellent agreement with Pauling's limiting value. A pressure of 1500 bars yields an additional maximum and shoulder between the two dispersion extrema from pure water; saturated NaCl in water shows the additional maximum. The maxima near 3350 cm(-1) (1500 bar) or near 3360 cm(-1) (NaCl-H(2)O) arise from bent H bonds; 3350 cm(-1) (1500 bar) corresponding to an angle of approximately 170 degrees in the joint frequency/bend, probability of Lawrence and Skinner. Rising omega refers to a higher probability of larger O-O distances, bent H bonds, and H-bond weakening and breakage. A approximately 50-80 cm(-1) difference between the 2727 cm(-1) OD peak from HDO in steam, and the 2650-2675 cm(-1) dispersion maximum is explained via the very broad approximately 60 cm(-1) liquid peak observed at 342 degrees C and 2000 bar.
An assay for pyrimidine deoxyribonucleoside kinase using γ-32P-labeled ATP

Abstract A rapid, simple and sensitive assay for pyrimidine deoxyribonucleoside kinase is described. After phosphorylation of unlabeled nucleoside substrate through the transfer of the γ-phosphate of [γ- 32 P]ATP, the reaction mixture is subjected to 1 n HCl at 100°C. The β- and γ-phosphates of unreacted ATP are hydrolyzed to inorganic phosphate while the 5′-phosphate of the pyrimidine deoxyribonucleotide product is not hydrolyzed. Radioactive phosphate remaining in the supernatant fluid after precipitation of inorganic phosphate corresponds to product and is measured by liquid scintillation spectrometry. Evidence is presented suggesting that pyrimidine and purine ribonucleoside kinase activity can also be determined by this assay.
β‐ENDORPHIN: ISOLATION, AMINO ACID SEQUENCE AND SYNTHESIS OF THE HORMONE FROM HORSE PITUITARY GLANDS

Beta-endorphin has been isolated from equine pituitaries. Its amino acid sequence is identical to that of ovine, bovine and camel beta-endorphins except for substitution of the threonine residue at position 6 by serine. The equine beta-endorphin has also been synthesized by the solid-phase method. In comparison with the human hormone, equine beta-endorphin was shown to possess 3 times the receptor-binding activity in rat membrane preparations and 1.6 times the analgesic potency in the mouse tail-flick assay.
Synergy between pretreatment lignocellulose modifications and saccharification efficiency in two brown rot fungal systems.

Brown rot wood-degrading fungi distinctly modify lignocellulose and completely hydrolyze polysaccharides (saccharification), typically without secreting an exo-acting glucanase and without removing lignin. Although each step of this two-step approach evolved within the same organism, it is unknown if the early lignocellulose modifications are made to specifically facilitate their own abbreviated enzyme system or if enhancements are more general. Because commercial pretreatments are typically approached as an isolated step, answering this question has immense implication on bioprocessing. We pretreated spruce and pine blocks with one of two brown rot fungi, Gloeophyllum trabeum or Fomitopsis pinicola. Wood harvested at weeks 1, 2, 4, and 8 showed a progression of weight loss from time zero due to selective carbohydrate removal. Hemicellulose losses progressed faster than cellulose loss. This “pretreated” material was then saccharified with commercially relevant Trichoderma reesei cellulases or with cellulases from the brown rot fungi responsible for degrading the wood to test for synergy. With increased decay, a significant increase in saccharification efficiency was apparent but not limited to same-species enzyme sources. We also calculated total sugar yields, and calculations that compensate for sugars consumed by fungi suggest a shorter residence time for fungal colonization than calculations based solely on saccharification yields.
Exotic plants and their effects in southeastern Florida.

Europeans began introducing plants into southeastern Florida during the 16th century, and by the middle of the 18th century several of these were already naturalized. Few of these events have been recorded, but we know that the Guava, Papaya, and oranges, were among the early immigrants. American settlement in the middle 1800s began another phase of plant movement which continues to the present. H. M. Flagler, Henry Nehrling, John C. Gifford, and others, brought plants in for landscaping or other uses. Among those brought in by the United States Department of Agriculture were the Sisal, introduced by Henry Perrine, and the many food and ornamental plants sent by David Fairchild to the Miami Introduction Station. Many of the plants brought to Florida have become important as ornamentals or foods; however, some of the exotics have escaped and now present problems to the native ecosystems and to Man.Over 170 species of ferns and flowering plants are naturalized in southeastern Florida. Hundreds of other exotic plants have been introduced into the region and the potential exists for others to escape. Species such as Melaleuca quinquenervia are invading wet habitats and decreasing diversity; the Australian Pine (Casuarina equisetifolia) has become so abundant on some beaches that it interferes with nesting seaturtles and American Crocodiles, as well as contributing to dune erosion. Water-hyacinth (Eichhornia crassipes) and Florida Elodea (Hydrilla verticillata) clog natural and artificial lakes, ponds, and canals, blocking boat traffic and slowing water movement. Several grasses that were introduced as pasture plants are now considered pests. Even human health is being threatened by exotic plants such as the Melaleuca and Pepper-tree (Schinus terebinthifolius), which cause respiratory allergies and contact dermatitis.
Motion of trapped electrons and protons in Saturn's inner magnetosphere

A summary is given of basic formulas for the guiding center motion of energetic charged particles trapped in a dipolar magnetic field. These formulas for longitudinal drift rates, latitudinal bounce periods, equatorial gyroradii, and equatorial gyroperiods are then stated in convenient numerical form for electrons and protons as functions of kinetic energy E, magnetic shell parameter L, and equatorial pitch angle alpha 0 for a slightly simplified model of the observed magnetic field of Saturn. To aid in the study of the interaction of charged particles with the rings and inner satellites of Saturn, additional formulas are given for the time interval between successive encounters of charged particles with a satellite in a circular prograde orbit and for the energy of electrons whose longitudinal angular velocity is resonant, or synchronous, with the Keplerian angular velocity of such a satellite.
A general theory of heat conduction with finite wave speeds

> 0 is a constant. This equation, which is parabolic, has a very unpleasant feature: a thermal disturbance at any point in the body is felt instantly at every other point; or in terms more suggestive than precise, the speed of propagation of disturbances is infinite. In this paper we develop a general theory of heat conduction for nonlinear materials with memory, a theory which has associated with it finite propagation speeds. In Section 3 we determine the restrictions that thermodynamics places on our constitutive relations. We show that our theory differs f rom other theories of heat conduction in that the heat-flux, like the entropy, is determined by the functional for the free-energy. In Section 6 we study the propagation of certain types of weak discontinuities. We show that in certain circumstances waves travelling in the direction of the heat-flux vector propagate faster than waves travelling in the opposite direction. In Section 7 we deduce the linearized theory appropriate to infinitesimal temperature gradients. We show that the linearized constitutive equation for the heat-flux q has the form: 1
X-expressions in XMLisp: S-expressions and extensible markup language unite

XMLisp unites S-expressions with XML into X-expressions that unify the notions of data sharing with computation. Using a combination of the Meta Object Protocol (MOP), readers and printers, X-expressions uniquely integrate XML at a language, not API level, into Lisp in a way that could not be done with other programming languages. Integration at a language level has significant advantages by making XML tangible to the programmer throughout existing Lisp development tools including editors, debuggers, inspectors, listeners and compilers. This integration with Lisp tools enables XML development in the incremental development style Lisp programmers have become accustomed to. This article describes XMLisp in the context of the AgentCubes simulation and gameauthoring tool. AgentCubes is the 3D version of AgentSheets system, which is the world's most distributed Lisp-based educational simulation and game-authoring tool.
Liquid Crystallinity in para-Substituted Poly γ-benzyl-L-glutamates

Abstract The liquid crystalline behavior of poly γ-p-fluorobenzyl-L-glutamate, poly γ-p-trifluoromethylbenzyl-L-glutamate, poly γ-p-nitrobenzyl-L-glutamate, and poly γ-benzyl-L-glutamate has been investigated. The first two polymers are new materials while the synthesis of the latter two has been reported in the literature. Only the liquid crystalline properties of poly γ-benzyl-L-glutamate have been previously reported and this study was initiated in order to determine if electron withdrawing substituents in the para position would influence the liquid crystal behavior of these polymers. Poly γ-benzyl-L-glutamate was used as the reference standard to which the other three were compared. Under the experimental conditions employed, the equispacings for poly γ-benzyl-L-glutamate were 4–6 μm, poly γ-p-fluoro-benzyl-L-glutamate, 6–8 μm, poly γ-p-trifluoromethylbenzyl-L-glutamate, 7-9 μm, and poly γ-p-nitrobenzyl-L-glutamate, 11–15 μm. The equispacings for the para nitro polymer show the largest difference fro...
Sodium Uptake Associated with Activation of Action Potential Ionophores of Cultured Neuroblastoma and Muscle Cells

Abstract Veratridine, an activator of action potential Na+ ionophores, stimulated passive Na+ uptake by electrically excitable neuroblastoma and muscle cells but had no effect on clonal cell lines defective in Na+-ionophore activity. Veratridine-dependent Na+ uptake was completely inhibited by tetrodotoxin, a specific inhibitor of the action potential Na+ ionophore. Half-maximal inhibition was obtained with 11 nM tetrodotoxin. Thus, veratridinedependent Na+ uptake provides a specific and convenient means of assaying populations of cultured cells for action potential Na+-ionophore activity.
Implications of cost in treatment selection for patients with coronary heart disease

Background. The growth of managed care and other types of capitated payment systems for medical care has forced cost into the therapeutic equation. The benefits of treatment must now be balanced against their costs. Clinicians are being challenged to prove that what they do has sufficient "value". Particular targets for these challenges are surgeons and interventional cardiologists who, in aggregate, perform expensive high-volume procedures. Methods. A cost analysis of percutaneous transluminal coronary angioplasty, coronary artery bypass grafting, and medical management of coronary artery disease has been undertaken using the Duke University database of 4,000 patients. The costs of the three procedures were compared at several fixed time points. Results. The costs for the three treatments are critically dependent on the time points selected for comparison. At 60 days, the cost of the medical group was about one quarter the cost of the bypass group, whereas the cost of the angioplasty group was on average 60% of that of the surgical group. By 1 year, the costs in the angioplasty group reached 66% of those in the bypass group, but both remained far above the costs of medical therapy alone. There is a significant cost gradient for percutaneous transluminal coronary angioplasty as the extent of the disease increases, which is not apparent for coronary artery bypass grafting. Conclusions. Medical costs arise in a complex manner, and their prediction is difficult. Unexpected events during or after the initial treatment are a major cause of increased costs, and complications often cannot be predicted. Patient-related factors have only a small effect on costs in comparison with the choice of treatment. High-risk, high-cost patients tend to get the most benefit.
Transrectal ultrasonography for prostatic cancer. II. The response of the prostate to definitive radiotherapy

Transrectal ultrasonography was used to monitor the response of adenocarcinoma of the prostate to radiotherapy before and 6 to 15 months after treatment combining implantation of radioactive gold seeds with external beam irradiation. Data gathered before and after irradiation therapy suggested that the two most sensitive measures for monitoring the primary tumor are the calculated volume of the prostate and the integrity of the prostatic capsule. The calculated volume of the prostate decreased significantly in all patients by 6 months after radiotherapy. The rate and degree of reduction correlated significantly (P less than 0.05) with the histologic grade of the tumor (poorly differentiated tumors shrinking most rapidly), as well as with the outcome of treatment (P less than 0.05). However, there was no such correlation with stage. After treatment, the average number of sites of capsular disruption decreased steadily, reaching 50% of the pretreatment number by 15 months. Transrectal ultrasonography is a practical, inexpensive, noninvasive tool for monitoring the response of prostatic cancer to definitive radiotherapy, and may provide a means of identifying patients who will respond poorly to treatment.
''Sitting With the Sick'': African American Women's Philanthropy

This article traces the historical development of informal and, to a lesser extent, formal health caregiving among African Americanwomen from slavery to the Great Depression. “Sitting with the sick...
Examination of the role for Ca2+ in regulation and phosphorylation of the Na+/H+ antiporter NHE1 via mitogen and hypertonic stimulation.

It has been suggested that Ca2+ transients, acting through calmodulin-binding proteins, play a role in the activation of the Na+/H+ exchanger isoform NHE1 (Owen and Villereal, 1982a, Biochem. Biophys. Res. Commun., 109:762-768; 1982b, Proc. Natl. Acad. Sci. U.S.A., 79:3537-3541, Ober and Pardee, 1987, J. Cell. Physiol., 132:311-317). This is supported by a recent report that NHE1 is a calmodulin-binding protein and that loss of the high-affinity calmodulin-binding site results in alterations in antiporter function (Bertrand, et al., 1994, J. Biol. Chem., 269:13703-13709). An additional mechanism by which NHE1 is activated by mitogens is thought to be phosphorylation (Sardet, et al., 1990, Science 247:723-726). Although the calmodulin-binding region appears vital to antiporter activation, the role of phosphorylation is unclear. The studies presented here examine a role for Ca2+ in the activation and phosphorylation of NHE1 induced by serum and hypertonicity. It is apparent that the microsomal Ca2+ ATPase inhibitor thapsigargin activates antiporter function in human foreskin fibroblasts (HSWP) as determined by increased intracellular alkalinization examined by image analysis. This effect is Ca(2+)-dependent as the alkalinization is blocked when cells are preincubated with BAPTA, an intracellular Ca2+ chelator. Similarly, the effects of serum-induced intracellular alkalinization are inhibited by BAPTA. In contrast, activation of NHE1 by increased osmolarity was not inhibited by BAPTA. This suggests that serum, and not hypertonicity, increases intracellular pH via a Ca(2+)-dependent process. It was also observed that both thapsigargin and hypertonicity activate NHE1 by a phosphorylation-independent mechanism and that BAPTA did not block the serum-induced increase in phosphorylation of NHE1. These results indicate that Ca2+ plays the predominant role in the serum-induced activation of NHE1, while phosphorylation plays only a minor, if any, role in this process. However, Ca2+ does not appear to be involved in the osmotic regulation of NHE1.
Transesophageal Echocardiography: Better Information at a Higher Price?

Echocardiography has emerged as one of the most widely available and frequently utilized diagnostic tests in cardiovascular disease. This popularity is the result of several factors . The various ultrasound tests provide useful clinical information at relatively low cost with minimal patient risk or discomfort. The greatest limitation to continued growth is almost certainly the issue of image quality. In a minority of individuals, because of technical factors inherent to the patient or instrument, diagnostic-quality images cannot be recorded. As clinicians, we prefer our diagnostic tests to be noninvasive and inexpensive, but we must insist that high quality clinical information be obtained in all patients. It is within the framework of cost containment, image quality, and patient acceptance that the newest ultrasound modality, transesophagealechocardiography (TEE), finds itself uniquely positioned. The development of these instruments, an ultrasound transducer fitted to the end of an endoscope, offers echocardiographers a "mirror image" view of the heart, unaffected by hyperinfiated lungs and narrow intercostal spaces. High quality diagnostic imaging and the ability to monitor heart function during surgery are among the most frequently cited advantages of TEE. As a result, this semiinvasive procedure is rapidly gaining support as a useful clinical tool. A comprehensive review of this new modality is provided in this issue of the J OURNAL.l This synopsis
Coordination and control for large distributed sensor networks

As the complexity of power plants increase, so does the difficulty in accurately modeling the interactions among the subsystems. Distributed sensing and control offers a possible solution to this problem, but introduces a new one: how to ensure that each subsystem satisfying its control objective leads to the safe and reliable operation of the entire power plant. In this work we present a distributed coordination algorithm that offers safe, reliable, and scalable control of a distributed system. In this approach, each system component uses a reinforcement learning algorithms to achieve its own objectives, but those objectives are derived to coordinate implicitly and achieve the system level objective. We show that in a Time-Extended Defect Combination Problem where the agents need to determine when and whether or not they should be sensing in order to maintain QoS in a system, the proposed method outperforms traditional methods by up to two orders of magnitude.
Between Saying and Doing: Towards an Analytic Pragmatism

Brandom, Robert B., Between Saying and Doing: Towards an Analytic Pragmatism, Oxford: Oxford University Press, 2008, pp. 240, £18.99 (cloth). A central thesis of Robert Brandom's treatise Making It...
Structure and Sequence Conservation of hao Cluster Genes of Autotrophic Ammonia-Oxidizing Bacteria: Evidence for Their Evolutionary History

Comparison of the organization and sequence of the hao (hydroxylamine oxidoreductase) gene clusters from the gammaproteobacterial autotrophic ammonia-oxidizing bacterium (aAOB) Nitrosococcus oceani and the betaproteobacterial aAOB Nitrosospira multiformis and Nitrosomonas europaea revealed a highly conserved gene cluster encoding the following proteins: hao, hydroxylamine oxidoreductase; orf2, a putative protein; cycA, cytochrome c(554); and cycB, cytochrome c(m)(552). The deduced protein sequences of HAO, c(554), and c(m)(552) were highly similar in all aAOB despite their differences in species evolution and codon usage. Phylogenetic inference revealed a broad family of multi-c-heme proteins, including HAO, the pentaheme nitrite reductase, and tetrathionate reductase. The c-hemes of this group also have a nearly identical geometry of heme orientation, which has remained conserved during divergent evolution of function. High sequence similarity is also seen within a protein family, including cytochromes c(m)(552), NrfH/B, and NapC/NirT. It is proposed that the hydroxylamine oxidation pathway evolved from a nitrite reduction pathway involved in anaerobic respiration (denitrification) during the radiation of the Proteobacteria. Conservation of the hydroxylamine oxidation module was maintained by functional pressure, and the module expanded into two separate narrow taxa after a lateral gene transfer event between gamma- and betaproteobacterial ancestors of extant aAOB. HAO-encoding genes were also found in six non-aAOB, either singly or tandemly arranged with an orf2 gene, whereas a c(554) gene was lacking. The conservation of the hao gene cluster in general and the uniqueness of the c(554) gene in particular make it a suitable target for the design of primers and probes useful for molecular ecology approaches to detect aAOB.
Calculation of electrostatic interaction energies in molecular dimers from atomic multipole moments obtained by different methods of electron density partitioning

Accurate and fast evaluation of electrostatic interactions in molecular systems is still one of the most challenging tasks in the rapidly advancing field of macromolecular chemistry, including molecular recognition, protein modeling and drug design. One of the most convenient and accurate approaches is based on a Buckingham-type approximation that uses the multipole moment expansion of molecular/atomic charge distributions. In the mid-1980s it was shown that the pseudoatom model commonly used in experimental X-ray charge density studies can be easily combined with the Buckingham-type approach for calculation of electrostatic interactions, plus atom-atom potentials for evaluation of the total interaction energies in molecular systems. While many such studies have been reported, little attention has been paid to the accuracy of evaluation of the purely electrostatic interactions as errors may be absorbed in the semiempirical atom-atom potentials that have to be used to account for exchange repulsion and dispersion forces. This study is aimed at the evaluation of the accuracy of the calculation of electrostatic interaction energies with the Buckingham approach. To eliminate experimental uncertainties, the atomic moments are based on theoretical single-molecule electron densities calculated at various levels of theory. The electrostatic interaction energies for a total of 11 dimers of alpha-glycine, N-acetylglycine and L-(+)-lactic acid structures calculated according to Buckingham with pseudoatom, stockholder and atoms-in-molecules moments are compared with those evaluated with the Morokuma-Ziegler energy decomposition scheme. For alpha-glycine a comparison with direct "pixel-by-pixel" integration method, recently developed Gavezzotti, is also made. It is found that the theoretical pseudoatom moments combined with the Buckingham model do predict the correct relative electrostatic interactions energies, although the absolute interaction energies are underestimated in some cases. The good agreement between electrostatic interaction energies computed with Morokuma-Ziegler partitioning, Gavezzotti's method, and the Buckingham approach with atoms-in-molecules moments demonstrates that reliable and accurate evaluation of electrostatic interactions in molecular systems of considerable complexity is now feasible.
Underground disposal of krypton-85 from nuclear fuel reprocessing plants☆

Abstract An evaluation is made of the different methods for large-scale removal of 85 Kr from the off-gas stream of a reprocessing plant and of the feasibility of underground disposal of 85 Kr. Although the apparent advantages of underground disposal are its relative simplicity and effectiveness, one severe requirement is that the disposal formation must be essentially free of vertical channels. The principal mechanisms by which 85 Kr may be retarded or retained underground include adsorption and trapping (containment). In the absence of convective transport, vertical underground movement is influenced by molecular diffusion. These mechanisms are evaluated for quantities of 85 Kr and volumes of off-gas assumed to be produced at a 10 tons/day reprocessing plant.
An exact solution of the time-invariant discrete Kalman filter

An exact solution is presented of the matrix Riccati difference equation associated with a time-invariant discrete Kalman filter. The time-varying solution is expressed by means of the corresponding steady-state algebraic solution. An exact solution of the closed-loop transition matrix is also presented.
A Stochastic Model of Gravity-Wave-Induced Clear-Air Turbulence

Abstract We examine the consequences of using a vertical wavenumber spectral model to describe variations of vertical profiles of atmospheric variables (horizontal and vertical wind, temperature, and other scalars) about a mean profile. At high wavenumbers the model exhibits a wavenumber to the -3 dependence, which is characteristic of a continuum of internal gravity waves whose amplitudes are controlled by a breaking process. By employing a random phase between wavenumber amplitude components, a reverse fourier transform of the spectrum yields simulated profiles of velocity and thermal variability as well as shear and Brunt–Vaisala frequency variability. Individual components of the vertical shear of the horizontal wind and the Brunt–Vaisala frequency exhibit Gaussian distributions; the square of the magnitude of the shear exhibits a Rice–Nakagami distribution. Assuming regions with Ri < 0.25 are turbulent, we can examine a number of aspects of the occurrence of clear-air turbulent breakdown in the strat...
Imaging plasma docosahexaenoic acid (dha) incorporation into the brain in vivo, as a biomarker of brain DHA: Metabolism and neurotransmission

Docosahexaenoic acid (DHA) is critical for normal brain structure and function, and its brain concentration depends on dietary DHA content and hepatic conversion from its dietary derived n-3 precursor, a-linolenic acid (α-LNA). We developed an in vivo method in rats using quantitative autoradiography to image incorporation into brain of unesterified plasma DHA, and showed that the incorporation rate equals the rate of brain metabolic DHA consumption. Thus, quantitative imaging of DHA incorporation from plasma into brain can be used as a biomarker of brain DHA metabolism and neurotransmission. The method has been extended to humans with the use of positron emission tomography (PET). Furthermore, imaging in unanesthetized rats using DHA incorporation as a biomarker in response to N-methyl-D-aspartate (NMDA) administration confirms that regional DHA signaling is independent of extracellular calcium, and likely mediated by a calcium-independent phospholipase A2 (iPLA2). Studies in mice in which iPLA2-VIA (β) was knocked out confirmed that this enzyme is critical for baseline and muscarinic cholinergic signaling involving DHA.
Successful Treatment of Fanconi Anemia and T-Cell Acute Lymphoblastic Leukemia

Fanconi anemia is associated with an increased risk of malignancy. Patients are sensitive to the toxic effects of chemotherapy. We report the case of a patient with Fanconi anemia who developed T-cell acute lymphoblastic leukemia. He experienced chemotherapy-related complications including prolonged neutropenia, grade IV vincristine neuropathy, and disseminated aspergillosis. He was successfully treated with modified dosing of cytarabine and intrathecal methotrexate followed by allogeneic bone marrow transplant. The aspergillosis was treated with systemic antifungal treatment and surgical resection. Now 30 months after bone marrow transplant the patient is without evidence of aspergillosis or leukemia.
Venomous bites by nonvenomous snakes: an annotated bibliography of colubrid envenomation

This bibliography lists 71 publications dealing with human envenomation by colubrid snakes during the years 1873–1988. This information appears in a wide variety of publications in medicine, herpetology, and toxicology. Fifty snake species, many conventionally considered nonvenomous, are included. Reports are divided into those showing evidence of systemic poisoning, usually associated with coagulopathy, and those showing only local signs and symptoms.
Characterization of the rat vasoactive intestinal polypeptide receptor gene 5' region.

The broad spectrum of vasoactive intestinal polypeptide (VIP) cellular functions are mediated by high-affinity binding sites. To determine regulation of the VIP receptor gene expression, we have isolated and characterized two genomic clones that contain the first three exons and the 5′ flanking region of the VIP receptor gene. Using RNase protection assays, receptor gene expression was detected in adult rat lung, liver and intestine, but not in fetal lung, indicating that VIP receptor is expressed in diverse tissues, and its expression is differentially regulated during lung development. The transcription start site of the gene was mapped to a cytosine residue, 76 bp upstream from the ATG initiation codon. Transfection into rat lung cell lines shows that although 126 bp of the VIP receptor 5′ DNA sequences are capable of activating VIP receptor gene basal transcription 30-fold over a promoterless control, 488 bp of the 5′ sequences further induce this activation to 97-fold over control. However, inclusion of up to 859 bp 5′ sequences results in a decrease in basal promoter activity (31-fold over control), indicating that while sequences between -126 and -488 bp contain potential enhancer sequences, sequences between -488 and -859 bp may include a transcriptional repressor sequence. Deletion analysis shows that transcription factor Sp1 plays an important role in activating basal promoter of the VIP receptor gene. DNase I footprinting and gel-mobility-shift assays show that Sp1 binds to its consensus binding sites in the VIP receptor promoter, suggesting that interaction of Sp1 with VIP receptor promoter transactivates this gene.
Movies for the Political Science Classroom: A Discussion List

Listed below are movies that compliment chapters for Political Science/American Government textbooks. Please consider using these movies as extra credit or as midterm projects in your undergraduate courses. One assignment I have used is to have students prepare a paper summarizing the movie, including its plot and main characters, relate it to the corresponding textbook chapter (complete with citations to page numbers), and provide a conclusion that expresses the student's opinion about the movie. You will find that students love to add on to this list. However, please preview any student-suggested movie as to its appropriateness before incorporating it into your class.
Canine elliptocytosis due to a mutant β‐spectrin

A 5-year-old, spayed female, mixed-breed dog with persistent elliptocytosis was evaluated at the Veterinary Medical Teaching Hospital at Kansas State University. The elliptocytosis was asymptomatic and was detected during the evaluation of lameness. When subjected to shear stress in an ektacytometer, the dog's erythrocytes had reduced cellular deformability and erythrocyte membranes had decreased mechanical stability. Analysis of erythrocyte membrane spectrin by nondenaturing gel electrophoresis revealed an increased amount of spectrin dimers, indicating a defect in spectrin self-association. DNA analysis detected a beta-spectrin mutation in codon 2110 in which threonine was replaced by methionine. This mutation likely altered the molecular structure of the erythrocyte membrane, leading to impaired spectrin self-association and elliptocyte formation.
Alteration of the Expression of Pesticide-Metabolizing Enzymes in Pregnant Mice: Potential Role in the Increased Vulnerability of the Developing Brain

Studies on therapeutic drug disposition in humans have shown significant alterations as the result of pregnancy. However, it is not known whether pesticide metabolic capacity changes throughout pregnancy, which could affect exposure of the developing brain. We sought to determine the effect of pregnancy on the expression of hepatic enzymes involved in the metabolism of pesticides. Livers were collected from virgin and pregnant C57BL/6 mice at gestational days (GD)7, GD11, GD14, GD17, and postpartum days (PD)1, PD15, and PD30. Relative mRNA expression of several enzymes involved in the metabolism of pesticides, including hepatic cytochromes (Cyp) P450s, carboxylesterases (Ces), and paraoxonase 1 (Pon1), were assessed in mice during gestation and the postpartum period. Compared with virgin mice, alterations in the expression occurred at multiple time points, with the largest changes observed on GD14. At this time point, the expression of most of the Cyps involved in pesticide metabolism in the liver (Cyp1a2, Cyp2d22, Cyp2c37, Cyp2c50, Cyp2c54, and Cyp3a11) were downregulated by 30% or more. Expression of various Ces isoforms and Pon1 were also decreased along with Pon1 activity. These data demonstrate significant alterations in the expression of key enzymes that detoxify pesticides during pregnancy, which could alter exposure of developing animals to these chemicals.
Collaboration between Child Welfare and Substance-Abuse Fields: Combined Treatment Programs for Mothers

Objective To review collaboration between child welfare and drug-abuse fields in providing treatment to mothers who abuse drugs and maltreat their children. Methods Literature review of studies examining effects of maternal drug abuse on parenting skills and outcomes of interventions for both maternal drug abuse and parenting skills. Results Parenting skills differ between mothers who do and do not abuse drugs, but these studies are primarily limited to mothers of infants and preschoolers. The evidence base for interventions to address both substance use and parenting in these mothers is growing, but more well-controlled studies are needed. Opportunities for improved collaboration between fields are presented. Conclusion Progress has been made toward collaboration to address drug abuse and parenting skills of mothers who abuse drugs, but more integrated strategies are needed, especially for mothers who use drugs and maltreat their children.
Trends in Artificial Intelligence

THIS Special Issue on Artificial Intelligence in the IEEE TRANSACTIONS ON COMPUTERS is composed of selected papers from the 3rd International Joint Conference on Artificial Intelligence (IJCAI), Stanford University, Stanford, CA, 1973. Far more high-quality papers have been presented at these conferences erences than can be accommodated in any one journal. However, the interdisciplinary nature of artificial intelligence (AI) means that IJCAI papers regularly appear in several journals.
A study of malware in peer-to-peer networks

Peer-to-peer (P2P) networks continue to be popular means of trading content. However, very little protection is in place to make sure that the files exchanged in these networks are not malicious, making them an ideal medium for spreading malware. We instrument two different open source P2P networks, Limewire and OpenFT, to examine the prevalence of malware in P2P networks. Our results from over a month of data show that 68% of all downloadable responses in Limewire containing archives and executables contain malware. The corresponding number for OpenFT is 3%. Also, most infections are from a very small number of distinct malware. In particular, in Limewire, the top three most prevalent malware account for 99% of all the malicious responses. The corresponding number for OpenFT is 75%. We also investigate the sources of malicious responses. To our surprise, 28% of all malicious responses in Limewire come from private address ranges. In OpenFT, the top virus, which accounts of 67% of all the malicious responses, is served by a single host. Further, our study provides a useful insight into filtering malware: filtering downloads based on the most commonly seen sizes of the most popular malware could block a large portion of malicious files with a very low rate of false positives. While current Limewire mechanisms detect only about 6% of malware containing responses, our size based filtering would detect over 99% of them.
Atmospheric Measurements of Sub-20 nm Diameter Particle Chemical Composition by Thermal Desorption Chemical Ionization Mass Spectrometry

We report the first online measurements of the chemical composition of atmospheric aerosol in the 6–20 nm diameter range. These measurements were performed using the recently developed Thermal Desorption Chemical Ionization Mass Spectrometer (TDCIMS), and were made possible by recent sensitivity enhancements resulting from (a) the development of a unipolar charger optimized for high aerosol flow rates, and (b) an improved flow system in the TDCIMS sample inlet. Measurements of atmospheric aerosol in Boulder, CO revealed large concentration variations in most detected compounds. The most dominant observed compounds in the negative ion TDCIMS spectra were nitrate and sulfate, while in the positive ion spectra ammonium dominated all other observed compounds. Comparison with laboratory data suggests that particles are composed primarily of ammonium sulfate during times of relatively low ambient aerosol concentration.
Inferences about members of kinds: The generics hypothesis

People routinely make inferences based on kind membership. For example, if you were told that a particular kind of animal is a tiger, then you would likely infer that it has stripes. Under what conditions are people willing to infer that a member of a given kind has a property? Two hypotheses were examined. The base rate or prevalence hypothesis holds that people rely only on their knowledge of the statistical frequency of a property among its kind to infer whether a member has that property. An alternative is the generics hypothesis, which states that people are influenced by their belief that the relevant generic generalization is true. In other words, if people agree to the generalization, ‘‘ducks lay eggs’’, then they should be willing to make the inference that an arbitrary individual duck lays eggs, despite their knowledge that the majority of ducks do not lay eggs (i.e., juveniles, males, and infertile females). We present data that support the second hypothesis. Rather than being driven solely by beliefs about prevalence, agreement to the relevant generic predicted performance on an inference task beyond estimated prevalence or cue validity. These findings suggest that models of categorization that are based solely on statistical or simple probabilistic principles are incomplete. They also provide support for the idea that generics articulate core conceptual beliefs that guide our interactions with the world.
Fluoroskopie. Öffentliche Demonstration der Wirkung der Röntgenstrahlen. Anfänge der Röntgenkinematographie

Schon fruher wurde darauf aufmerksam gemacht, das bei den mannigfachen Verbesserungen in der Erzeugung und Anwendung der Rontgenstrahlen viele Forscher zu gleicher Zeit auf dieselben Ideen kamen oder an demselben Problem arbeiteten. Eines der besten Beispiele dieses auserordentlichen Wetteifers im Auffinden neuer Verwendungsmoglichkeiten der Rontgenstrahlen ist die Konstruktion des Fluoroskops oder des verbesserten Leuchtschirmes.
Current Update on the Status of Totally Percutaneous Aneurysm Repair

The evolution of minimally invasive procedures to treat aortic aneurysms has expanded to include access interventions as well. Traditionally, groin exposures have been the standard approach for common femoral artery exposure with open cutdown; however, inherent and related complications to that approach have paved the road to the percutaneous approach. Current available evidence from the literature supports the feasibility and the safety of percutaneous endovascular aneurysm repair (PEVAR); however, predictors of success are not well defined. We should examine all available studies (both prospective and retrospective) in order to draw a conclusion and evidence-based outcome for selecting patients who would benefit the most from PEVAR.
Low Levels of Circulating Estrogen Sensitize PTEN-null Endometrial Tumors to PARP Inhibition In Vivo

Earlier in vitro work demonstrated that PARP inhibition induces cell death in PTEN-null endometrial cancer cell lines, but the in vivo therapeutic efficacy of these agents against endometrial cancer remains unknown. Here, we test the efficacy of AZD2281 (olaparib), an oral PARP inhibitor, in the therapy of PTEN-null endometrial tumors in a preclinical endometrial cancer mouse model. Primary endometrial tumors were generated by epithelial loss of PTEN using an in vivo model. This model recapitulates epithelial-specific loss of PTEN seen in human tumors, and histologically resembles endometrioid carcinomas, the predominant subtype of human endometrial cancers. Olaparib was administered orally to tumor-bearing mice in two hormonal extremes: high or low estrogen. Olaparib treatment achieved a significant reduction in tumor size in a low estrogenic milieu. In striking contrast, no response to olaparib was seen in tumors exposed to high levels of estrogen. Two key observations were made when estrogen levels were dropped: (i) the serum concentration of olaparib was significantly increased, resulting in sustained PARP inhibition at the tumor bed; and (ii) the homologous recombination pathway was compromised, as evidenced by decreased Rad51 protein expression and function. These two mechanisms may account for the sensitization of PTEN-null tumors to olaparib with estrogen deprivation. Results of this preclinical trial suggest that orally administered PARP inhibitors in a low estrogenic hormonal milieu can effectively target PTEN-null endometrial tumors. Extension of this work to clinical trials could personalize the therapy of women afflicted with advanced endometrial cancer using well-tolerated orally administered therapeutic agents.
On the Positivity of Operators

In this chapter, we shall explore the following theme: “Given a set of functions {u} satisfying certain side conditions, and an operator L that can he applied to the functions of this set, determine when the inequality $$ L\left( u \right) \geqq 0 $$ (1) implies that u ≧ 0.” An operator will be said to be “positive” if this condition is satisfied, although it might be more reasonable to call the inverse operator L −1 positive. We shall focus our attention upon ordinary differential and partial differential operators.