cssi/SciSciGPT-SciSciNet huggingface dataset:
Zeeman Effect of the Forbidden Lines of Potassium

The Zeeman effect of the lines $S\ensuremath{-}S$ and $S\ensuremath{-}D$, absorbed by potassium vapor in an electric field of about 2000 volts/cm, is studied. A magnetic field of 27,000 gauss was obtained by using the magnet of the new Berkeley cyclotron. The lines $4S\ensuremath{-}14S$ to $4S\ensuremath{-}19S$ show no effect, except for a slight broadening of the last one or two lines. The Zeeman patterns for $4S\ensuremath{-}12D$ to $4S\ensuremath{-}15D$, with the magnetic field perpendicular to the electric field and to the direction of observation, are resolved. They agree with the predicted pattern $\frac{0(1)2}{1}$, and show qualitatively the expected intensities.
Design of a disk file head-positioning servo

The engineering design of a head-positioning system for an interchangeable-medium disk file is considered. Emphasis is placed upon three specific functions within the positioning system: (I) encoding and demodulation of information from the dedicated servo surface, (2) compensation and dynamics of the track-following control system, and (3) implementation of control electronics for a quasi-time-optimal, track-accessing control system. The examples used are taken from the IBM 3340 Disk Storage Facility.
De Novo Ceramide Regulates the Alternative Splicing of Caspase 9 and Bcl-x in A549 Lung Adenocarcinoma Cells DEPENDENCE ON PROTEIN PHOSPHATASE-1

Previous studies have demonstrated that several splice variants are derived from both the caspase 9 and Bcl-x genes in which the Bcl-x splice variant, Bcl-x(L) and the caspase 9 splice variant, caspase 9b, inhibit apoptosis in contrast to the pro-apoptotic splice variants, Bcl-x(s) and caspase 9. In a recent study, we showed that ceramide induces the dephosphorylation of SR proteins, a family of protein factors that regulate alternative splicing. In this study, the regulation of the alternative processing of pre-mRNA of both caspase 9 and Bcl-x(L) was examined in response to ceramide. Treatment of A549 lung adenocarcinoma cells with cell-permeable ceramide, D-e-C(6) ceramide, down-regulated the levels of Bcl-x(L) and caspase 9b mRNA and immunoreactive protein with a concomitant increase in the mRNA and immunoreactive protein levels of Bcl-x(s) and caspase 9 in a dose- and time-dependent manner. Pretreatment with calyculin A (5 nm), an inhibitor of protein phosphatase-1 (PP1) and protein phosphatase 2A (PP2A) blocked ceramide-induced alternative splicing in contrast to okadaic acid (10 nm), a specific inhibitor of PP2A at this concentrations in cells, demonstrating a PP1-mediated mechanism. A role for endogenous ceramide in regulating the alternative splicing of caspase 9 and Bcl-x was demonstrated using the chemotherapeutic agent, gemcitabine. Treatment of A549 cells with gemcitabine (1 microm) increased ceramide levels 3-fold via the de novo sphingolipid pathway as determined by pulse labeling experiments and inhibition studies with myriocin (50 nm), a specific inhibitor of serine palmitoyltransferase (the first step in de novo synthesis of ceramide). Treatment of A549 cells with gemcitabine down-regulated the levels of Bcl-x(L) and caspase 9b mRNA with a concomitant increase in the mRNA levels of Bcl-x(s) and caspase 9. Again, inhibitors of ceramide synthesis blocked this effect. We also demonstrate that the change in the alternative splicing of caspase 9 and Bcl-x occurred prior to apoptosis following treatment with gemcitabine. Furthermore, doses of D-e-C(6) ceramide that induce the alternative splicing of both caspase 9 and Bcl-x-sensitized A549 cells to daunorubicin. These data demonstrate a role for protein phosphatases 1 (PP1) and endogenous ceramide generated via the de novo pathway in regulating this mechanism. This is the first report on the dynamic regulation of RNA splicing of members of the Bcl-2 and caspase families in response to regulators of apoptosis.
National governance and global lending

Abstract Global capital markets expanded rapidly during the latter part of the 20th century. Many access these global capital markets, but many others watch from the sidelines. National political arrangements help account for systematic disparities in access to global capital. Investigators employ a variety of measures and strategies as they try to understand the influence of political arenas upon economic activity. As they try to access political effects, some use relatively objective measures based upon formal political institutional arrangements, and others use more subjective measures to reflect the influence of the political arena. I suggest the formal institutional approach works well for developed political economies but exposes research to measurement problems when applied to developing nations where political institutional arrangements are emerging and have yet to gain firm footholds in society. Using more subjective measures, I show that democracy and regulatory stability matter as they influence investor behavior. Lending in global capital markets correlates well with better regulatory arenas and greater democracy. These provide information to international investors about threats from the state, which affects expectations about the risk to investments from local arenas.
Enzymologic Defect in the R347H and R358Q Mutations in P450c17 that Cause Selective 17,20-Lyase Deficiency • 425

Enzymologic Defect in the R347H and R358Q Mutations in P450c17 that Cause Selective 17,20-Lyase Deficiency • 425
ATP increases intracellular calcium in supraoptic neurons by activation of both P2X and P2Y purinergic receptors

ATP increases intracellular calcium concentration ([Ca2+]i) in supraoptic nucleus (SON) neurons in hypothalamo-neurohypophyseal system explants loaded with the Ca2+-sensitive dye, fura 2-AM. Involv...
Synthesis of amino nitrogen from ammonia in Hymenolepis diminuta.

Summary1. H. diminuta, in the presence of alpha-ketoglutaric acid, pyruvic acid, or oxalacetic acid and ammonium ions is capable of synthesizing amino nitrogen. It appears that this synthesis is so biased that the pyruvic acid-alanine system is favored. 2. Glucose, through its degradation to intermediary keto acids, is also capable of serving as a substrate for the synthesis of amino nitrogen from ammonium nitrogen. The yield, however, does not approach that of the more direct systems. 3. Evidence is given to show that the tri-carboxylic cycle actively functions in the living intact worm.
A surprising METamorphosis: Autism genetics finds a common functional variant

Autism is a devastating neurodevelopmental syndrome characterized by fundamental impairments in reciprocal social interactions, delayed and deviant language development, and restricted interests and/or highly repetitive stereotyped behaviors. Approximately 13 in 10,000 individuals are affected. There are several related clinical disorders, including Asperger's syndrome and pervasive developmental disorder not otherwise specified, which, along with autism, are collectively known as autism spectrum disorders (ASDs) and increase the prevalence estimates to ≈60 in 10,000 (1). Although ASDs have been shown to have among the greatest heritability of any neuropsychiatric syndrome (1), specific genes causing or increasing the risk for social disability have been extremely difficult to identify. Nonetheless, over the past several years, a transformation has begun: After two decades of frustration, rare functional variants contributing to a small number of ASD cases have been identified (2), a convergence of linkage data from different studies and patient samples has begun to emerge (3), and promising results have recently been reported from association studies of common genetic polymorphisms (4). In addition, there have been dramatic advances in the understanding of the neurobiology of single-gene syndromes, such as Fragile X, in which affected individuals may also display an autism behavioral phenotype (5). In this issue of PNAS, Campbell et al. (6) now take the next step in solving the puzzle of ASD genetics. These investigators report a large-scale, methodologically rigorous candidate gene-association study and provide exciting genetic and molecular biological evidence pointing to a common functional variant in the promoter of the MET gene as the contributing risk factor. The identification of an association of a specific common functional allele, if replicated, would be an unprecidented advance in autism genetics.
namehelp: intelligent client-side DNS resolution

The Domain Name System (DNS) is a fundamental component of today's Internet. Recent years have seen radical changes to DNS with increases in usage of remote DNS and public DNS services such as OpenDNS. Given the close relationship between DNS and Content Delivery Networks (CDNs) and the pervasive use of CDNs by many popular applications including web browsing and real-time entertainment services, it is important to understand the impact of remote and public DNS services on users' overall experience on the Web. This work presents a tool, namehelp, which comparatively evaluates DNS services in terms of the web performance they provide, and implements an end-host solution to address the performance impact of remote DNS on CDNs. The demonstration will show the functionality of namehelp with online results for its performance improvements.
An ab initio mo study of calcium and magnesium complexes with malonate and formate

Abstract Quantum mechanical SCF calculations were performed on magnesium and calcium complexes of malonate and malonate/formate coordination. The calcium malonate structure is in substantial agreement with recent X-ray results on α-ethylmalonate. The magnesium complexes are generally more tightly bound than calcium, although qualitatively, the calcium and magnesium structures are similar. Experimental binding results for divalent ions with malonates and EDTA are discussed in view of the current calculations.
Circle theorems for inviscid steady flows

Abstract General circle theorems which localize the complex eigenfrequencies arising in the linear stability analysis of conservative steady flows are given. Howard's circle theorem for incompressible plane parallel flow is contained as a special case. Two applications are considered: swirling flow of an inviscid incompressible fluid, and rotating flow of an inviscid, incompressible, perfectly conducting magnetofluid with an axial magnetic field. Circle theorems are obtained for the complex eigenfrequencies of any normal mode.
The Effect of PEEP on Left Ventricular Diastolic Dimensions and Systolic Performance Following Myocardial Revascularization

To quantitate the alterations in left ventricular (LV) dimensions and performance at successive levels of positive end-expiratory pressure (PEEP), 16 patients undergoing coronary artery bypass grafting (CABG) underwent instrumentation with ultrasonic dimension transducers to measure the minor-axis diameter of the left ventricle. Matched micromanometers were placed to measure intracavitary LV pressure and intrathoracic pressure. LV pressure and dimension data were recorded and computer analyzed during continuous positive-pressure ventilation at 0, 5, 10, and 15 cm H2O of PEEP 4 to 8 hours postoperatively. Preload was determined by the end-diastolic minor-axis diameter, cardiac output was measured by thermodilution, and indices of LV contractility assessed included the maximal velocity of minor-axis shortening and the slope of the end-systolic pressure-diameter relationship. PEEP produced a progressive increase in intrathoracic pressure associated with a fall in cardiac output; this was associated with a decrease in LV end-diastolic diameter and no significant change in the maximal velocity of minor-axis shortening or the slope of the end-systolic pressure-diameter relationship. Our results indicate that PEEP of 10 cm H2O or greater will produce a significant fall in cardiac output in patients following CABG, due to a decrease in preload rather than impaired LV contractility.
Synthesis of N-(chloromethyl)-2,6-diethylcarbaniloyl chloride (1) and derivatives†

The reaction of N-methylene-2,6-diethylbenzenamine with phosgene furnished the titled compound 1. The reaction of 1 with the potassium salts of various thiazolethiols in an acetone medium afforded the expected N-substituted 2,6-diethylthiolcarbanilates 2–6. Substituting the above thiazolethiols with the potassium salt of 2-mercaptobenzimidazole furnished a novel heterocyclic compound 7 in 98% yield. The rection of 1 with the triethylamine salt of disubstituted-dithiocarbamic acids afforded an alternate method for the synthesis of bis(N-substituted-thiocarbonyl)sulfides 8 and 9.
The DEKA Arm: Its features, functionality, and evolution during the Veterans Affairs Study to optimize the DEKA Arm:

Background and aim:DEKA Integrated Solutions Corp. (DEKA) was charged by the Defense Advanced Research Project Agency to design a prosthetic arm system that would be a dramatic improvement compared...
Andreev conductance of chaotic and integrable quantum dots

We examine the voltage V and magnetic field B dependent Andreev conductance of a chaotic quantum dot coupled via point contacts to a normal metal and a superconductor. In the case where the contact to the superconductor dominates, we find that the conductance is consistent with the dot itself behaving as a superconductor-- it appears as though Andreev reflections are occurring locally at the interface between the normal lead and the dot. This is contrasted against the behaviour of an integrable dot, where for a similar strong coupling to the superconductor, no such effect is seen. The voltage dependence of the Andreev conductance thus provides an extremely pronounced quantum signature of the nature of the dot's classical dynamics. For the chaotic dot, we also study non-monotonic re-entrance effects which occur in both V and B.
Bifunctional condensation reactions of alcohols on basic oxides modified by copper and potassium

Alcohol dehydrogenation and condensation reactions are involved in chain growth pathways on Cu/MgCeOxpromoted with potassium. These pathways lead to the formation of isobutanol with high selectivity via reactions of higher alcohols with methanol-derived C1species in reaction steps also relevant to higher alcohol synthesis from CO/H2mixtures at higher pressures on K–Cu/MgCeOxcatalysts. Ethanol reactions on K–CuyMg5CeOxshow that both Cu and basic sites participate in alcohol dehydrogenation and aldol condensation steps leading to n-butyraldehyde and acetone. Chain growth occurs by condensation reactions involving a metal-base bifunctional aldol-type coupling of alcohols. Reactions of12C2H5OH–13C2H4O mixtures show that direct condensation reactions of ethanol can occur without requiring the intermediate formation of gas phase acetaldehyde. Reactions of C2H5OH/D2mixtures show that Cu sites increase the rate of aldol condensation by introducing recombinative desorption sites that remove hydrogen atoms formed in C–H activation steps leading to the unsaturated aldol-type species required for chain growth. Reactions of acetaldehyde and13C-labeled methanol lead predominantly to 1-13C-propionaldehyde and 2-13C-isobutyraldehyde, both of which lead to isobutanol during CO/H2reactions. Mixtures of propionaldehyde and13C-labeled methanol lead to singly-labeled isobutyraldehyde. Chain growth to C2+alcohols occurs via addition of a methanol-derived C1species to adsorbed oxygen-containing intermediates. The gradual appearance of13C in the unlabeled reactant within these mixtures shows that aldol coupling reactions are reversible. Reverse aldol condensation reactions after intramolecular hydride transfer lead to the formation of acetone from ethanol. Isobutyraldehyde is a preferred end-product of aldol-type chain growth reactions of alcohols because it lacks the two α-hydrogens required for subsequent chain growth.
Interfacial Phase Transition of an Environmentally Responsive Elastin Biopolymer Adsorbed on Functionalized Gold Nanoparticles Studied by Colloidal Surface Plasmon Resonance

The change in optical properties of colloidal gold upon aggregation has been used to develop an experimentally convenient colorimetric method to study the interfacial phase transition of an elastin-like polypeptide (ELP), a thermally responsive biopolymer. Gold nanoparticles, functionalized with a self-assembled monolayer (SAM) of mercaptoundecanoic acid onto which an ELP was adsorbed, exhibit a characteristic red color due to the surface plasmon resonance (SPR) of individual colloids. Raising the solution temperature from 10 degrees C to 40 degrees C thermally triggered the hydrophilic-to-hydrophobic phase transition of the adsorbed ELP resulting in formation of large aggregates due to interparticle hydrophobic interaction. Formation of large aggregates caused a change in color of the colloidal suspension from red to violet due to coupling of surface plasmons in aggregated colloids. The surface phase transition of the ELP was reversible, as seen from the reversible change in color upon cooling the suspension to 10 degrees C. The formation of colloidal aggregates due to the interfacial phase transition of adsorbed ELP was independently verified by dynamic light scattering of ELP-modified gold colloids as a function of temperature. Colloidal SPR provides a simple and convenient colorimetric method to study the influence of the solution environment, interfacial properties, and grafting method on the transition properties of ELPs and other environmentally responsive polymers at the solid-water interface.
Educational policy in the People's Republic of China: a political influence perspective

This paper first outlines the developmental stages and the ‘pendulum pattern’ of the educational policy in the People's Republic of China. It then inquires into the dynamics of the pendulum pattern by employing the political influence framework. This inquiry reveals that the pendulum pattern is attributed to the ups and downs of the radical group and the moderate group, each having its own background, goals, resources and strategies. The limitations of their orientations in educational policy are discussed.
HIV diagnostics: challenges and opportunities

Accurate HIV diagnostic testing continues to pose challenges, but there are also opportunities for assay performance improvements in key areas for specific intended-use settings. The genetic diversity of HIV can result in false and discordant results in assays that fail to detect new variant strains. The use of antiretroviral therapies has resulted in drug-resistant variants that require monitoring by sequencing and genotyping methods. Nucleic acid testing is the most sensitive and reliable platform for detection, but it is costly and limited to centralized testing facilities, making implementation difficult in resource-limited settings where HIV has hit the hardest. Rapid antibody tests suitable for point-of-care use are becoming more accessible in resource-limited settings, but these tests may not detect HIV during the acute infection stage. Emerging antigen/antibody combination assays are viable alternatives to nucleic acid testing for diagnosis of recent infections. Although patient monitoring (e.g., ...
Connection of an elementary class of parametric two-electron reduced-density-matrix methods to the coupled electron-pair approximations

Parametric two-electron reduced-density-matrix (p-2RDM) methods have recently been shown to exhibit accuracies greater than coupled cluster with single and double substitutions (CCSD) at a lower computational cost. In this paper we derive an elementary class of parametric 2-RDM methods with connections to the coupled electron pair approximations (CEPA). Three parametric 2-RDM methods p-2RDM/n are presented that correspond to the CEPA/n family where n = 1, 2, 3. We isolate the function distinguishing the stationary condition of the parametric 2-RDM methods from the nonlinear equations of CEPA. Calculations of energies, geometries, and harmonic frequencies show that p-2RDM/n and CEPA/n are very similar for a variety of closed-shell systems. Finally, each of the p-2RDM/n methods is extended to satisfy particle–hole symmetry by the removal of exclusion principle violating terms in the virtual space. These extensions denoted p-2RDM′/n are shown to be essential for the proper dissociation of CH radical. Both p-...
Understanding the Role of Aqueous Solution Speciation and Its Application to the Directed Syntheses of Complex Oxidic Zr Chlorides and Sulfates

The lack of an in-depth understanding of solution-phase speciation and its relationship to solid-state phase formation is a grand challenge in synthesis science. It has severely limited the ability of inorganic chemists to predict or rationalize the formation of compounds from solutions. The need to investigate mechanisms that underlie self-assembly has motivated this study of aqueous Zr-sulfate chemistry as a model system, with the goal of understanding the structures of oligomeric clusters present in solution. We used high-energy X-ray scattering (HEXS) data to quantify Zr correlations in a series of solutions as a function of sulfate concentration. The pair distribution function (PDF) from the sulfate-free sample reveals that the average oligomeric Zr moiety is larger than the tetrameric building unit, [Zr4(OH)8(H2O)16]8+, generally understood to dominate its solution speciation. At sulfate concentrations greater than 1 m (molal), bidentate sulfate is observed, a coordination not seen in Zr(SO4)2·4H2O ...
Tritrophic Effects of Host Plants on an Herbivore-Pathogen Interaction

ABSTRACT Tritrophic interactions may include directly harmful effects of host plants on herbivores, and directly or indirectly harmful effects of host plants on the natural enemies of herbivores. Tritrophic interactions involving parasitoids and predators have received considerable attention but less is known about how host plants affect entomopathogens. We compared growth and resistance to entomopathogenic nematodes for “woolly bear” caterpillars, Grammia incorrupta (=geneura) (Hy. Edwards) (Lepidoptera: Arctiidae) fed lettuce, Lactuca sativa L. (Asteraceae), versus threadleaf groundsel, Senecio longilobus Benth. (Asteraceae). Both plants are members of the Asteraceae, but only S. longilobus contains pyrrolizidine alkaloids. Caterpillars gained more mass when fed L. sativa compared with S. longilobus; yet, in one of four cases studied, resistance to nematodes was higher when caterpillars ate S. longilobus. Caterpillar resistance to nematodes did not differ between host plants in the other cases. In addit...
Analgesic, hemodynamic and respiratory effects of caudal epidurally administered ropivacaine hydrochloride in mares.

Objective To determine the analgesic, hemodynamic and respiratory effects, sedation and ataxia in mares of caudal epidural administration of ropivacaine hydrochloride solution. Study design Prospective, single-dose trial. Animals Ten healthy mares weighing from 475 to 565 kg. Methods Intravascular catheters and an epidural needle were placed after infiltration of the skin and subcutaneous tissues with 2% lidocaine. Ropivacaine (0.5%, 8 or 9 mL) was then injected epidurally at the fifth sacral or sacrococcygeal vertebrae, respectively. Analgesia was determined by lack of sensory perception to electrical stimulation (> 40 milliamps) and absence of response to needle pricks extending from coccyx to S2 dermatomes. Electrocardiogram, heart and respiratory rates, rectal temperature, arterial blood pressure, arterial acid-base (pH, standard bicarbonate and base excess), gas tensions (PO2, PCO2), PCV, oxyhemoglobin and total solids concentrations, and numerical scores of perineal analgesia, sedation (head drop), and ataxia (position of pelvic limbs) were determined before and during a 5-hour testing period. Analysis of variance (anova) with repeated measures was used to detect significant (p < 0.05) differences of mean values from baseline. Results Epidurally administered ropivacaine induced variable analgesia extending bilaterally from coccyx to S2 (three mares), coccyx to S3 (four mares), and coccyx to S4 (three mares), with minimal sedation, ataxia, and cardiovascular and respiratory disturbances of mares. Perineal analgesia was attained at 10 ± 4 minutes and lasted for 196 ±42 minutes (mean ± SD). Five mares demonstrated inadequate perineal analgesia, probably attributable to deviation of the spinal needle from the midline. They were successfully blocked with ropivacaine on another occasion. Epidural ropivacaine significantly reduced repiratory rates of mares and did not change other variables from baseline. Conclusions and clinical relevance Ropivacaine (0.5%, 8 mL 500 kg−1) can be administered caudal epidurally to produce prolonged (> 2.5 hours) bilateral perineal analgesia with minimal sedation, ataxia, and circulatory and respiratory disturbances in standing mares.
Potassium-Argon and Lead-Alpha Ages of Plutonic Rocks, Bokan Mountain Area, Alaska

Most of the granitic rocks in the Bokan Mountain area, southeastern Alaska, are early Paleozoic (probably Ordovician) judged by potassium-argon and lead-alpha age measurements. The Bokan Mountain Granite, the youngest intrusive unit in the area, belongs to a Mesozoic plutonic episode. These age measurements are the first direct evidence for the emplacement of early Paleozoic granitic intrusive rocks close to the Pacific margin of North America.
Biology of Laboratory-Reared Corn Aphids, Rhopalosiphum maidis (Homoptera: Aphididae)

The corn leaf aphid, Rhopalosiphum maidis (Fitch), was first described as Aphis maidis by Fitch (1856), who found it infesting corn. Since then, its life history has been studied and reported several times under uncontrolled conditions.
Using Series-Series Iwan-Type Models for Understanding Joint Dynamics

In mechanical assemblies, the energy loss induced by joints and interfaces can account for a significant portion of the overall structural dissipation. This work considers the dynamical behavior of an elastic rod on a frictional foundation as a model for the dissipation introduced by micro-slip in mechanical joints. In a quasi-static loading limit, the deformation of the rod and hence the frictional dissipation can be solved in closed form. The resulting model is a continuum model of series arrangements of parallel Jenkins elements. For a general class of normal load distributions, the resulting energy loss per forcing cycle follows a power-law and is qualitatively similar to observed experimental findings. Finally, these results are compared with those obtained from a discrete formulation of the rod including inertial effects. For loading conditions that are consistent with mechanical joints, the numerical results from the discrete model are consistent with the closed form predictions obtained in the quasistatic limit.
Partial Nephrectomy: Contemporary Outcomes, Candidate Selection, and Surgical Approach

Abstract Localized kidney cancer is ideally managed with surgical extirpation. Historically renal cell carcinoma has been treated with radical nephrectomy, but partial nephrectomy has become increasingly used because of a growing body of evidence demonstrating equivalent oncologic control and a potential benefit in overall survival. In this article, the authors demonstrate that partial nephrectomy carries excellent oncologic efficacy. They additionally review the growing indications for partial nephrectomy and factors influencing candidate selection. The authors also compare the relative outcomes of open and minimally invasive techniques. Several factors influence outcome, and surgeon experience should dictate the choice of technique.
Synthesis of Silver Nanoparticles in a Continuous Flow Tubular Microreactor

This paper describes the synthesis of silver nanoparticles in a continuous flow tubular microreactor using silver pentafluoropropionate as a single-phase reactant precursor. This precursor can be thermally reduced in isoamyl ether to form silver nanoparticles in the presence of trioctylamine. The reaction is suitable for continuous flow reactors because of the moderate temperature for the formation of silver nanoparticles. The produced silver nanoparticles can have a narrow size distribution. Temperature profiles of the reactant fluids are obtained to understand the formation of silver nanoparticles in the microreactor.
Analysis of Extended Surface

Previous work, by the author and others, pertaining to parameterizations for individual fins is reviewed. These parameterizations are the thermal transmission matrices and ratios that were devised to facilitate the analysis of an assembly of individual fins into an array of extended surface. An elaboration of the usefulness of these parameters, particularly with regard to their superiority over the notion of fin efficiency or fin effectiveness, is made. The concept of reciprocity is developed and the representation of an individual fin as a connection of just three simple resistances is developed. A procedure for the nodal analysis of finned arrays is developed via a matrix-oriented approach.
Anthropic bound on the cosmological constant

In recent cosmological models, there is an "anthropic" upper bound on the cosmological constant $\ensuremath{\Lambda}$. It is argued here that in universes that do not recollapse, the only such bound on $\ensuremath{\Lambda}$ is that it should not be so large as to prevent the formation of gravitationally bound states. It turns out that the bound is quite large. A cosmological constant that is within 1 or 2 orders of magnitude of its upper bound would help with the missing-mass and age problems, but may be ruled out by galaxy number counts. If so, we may conclude that anthropic considerations do not explain the smallness of the cosmological constant.
Molecular crowding and early evolution

The environment of protocells might have been crowded with small molecules and functional and non-specific polymers. In addition to altering conformational equilibria, affecting reaction rates and changing the structure and activity of water, crowding might have enhanced the capabilities of protocells for evolutionary innovation through the creation of extended neutral networks in the fitness landscape.
Further Toward a Theory of Agricultural Insurance

The economic theory of contracts is applied to agricultural insurance to show that, given full information, Pareto-optimal insurance contracts are actuarially fair, provide full coverage, and differ for each individual. The information problems of moral hazard and adverse selection prevent Pareto optimality from being attained. Several "second-best" solutions to these problems are applied to agricultural insurance. It is shown that information collection and the application of contract design principles are "second-best" solutions which may achieve the benefits of insurance at less cost than the current practice of public subsidies. In theory, agricultural insurance is an efficient risk-sharing mechanism. In practice, however, agricultural insurance has been a costly means of transferring risk from farmers to governments and/or other insurers. To induce farmers to participate in agricultural insurance, governments have borne significant subsidy costs (Hazell, Pomareda, and Valdes, p. 295). In a recent study, Ahsan, Ali, and Kurian (AAK) concluded that public subsidies are necessary to make agricultural insurance viable. They also showed that insurance will increase output relative to a case with no insurance. Thus, insurance is beneficial, particularly in less developed countries where increasing food supplies is a policy goal. For this reason, they concluded that public subsidization of insurance also is desirable. Their conclusions are derived from a simplified model of production with one output and one input. In this article, we consider a more general production model with multiple inputs and outputs; we show that AAK's conclusion about the benefits of insurance may not hold depending on the nature of the inputs and outputs as defined by the production function. Carl H. Nelson is an assistant professor of agricultural economics
The oto-palato-digital (OPD) syndrome in females

Abstract The oto-palato-digital syndrome appears to be an X-linked trait with variable expression in the female heterozygote. This includes fullness of lateral supraorbital ridges, retarded growth, and the roentgenographic signs seen in males. To date, no female heterozygote has had cleft palate.
Goals of referring acts

A pragmatic theory of reference is a theory that specifies and explains the human competence to use referring expressions in order to achieve certain goals. Since the r e l a t i o n between referring expressions and speaker's goals is what needs explaining, it is natura l to consider referring as planned action [1,4,5]. This, in turn, requires showing how the use of referring expressions is systematically related to changes in the hearer 's mental state. For that purpose, we need to know the speaker's goals concerning the hearer 's mental state, and therefore, a pragmatic theory of referring must first of all specify and describe the goals that typically motivate the use of referring expressions. It is with such goals tha t this paper is concerned. The view that the referring act is a planned effort to achieve certain goals through linguistic means simply follows from the fact that referring is a speech act: all speech acts are at tempts to achieve certain goals through linguistic means. However, referring acts (and in general, propositional acts) are significantly different from illocutionary acts such as asserting and requesting:
Effects of Chronic Ethanol Exposure on GABA Receptors and GABAB Receptor Modulation of 3H‐GABA Release in the Hippocampus

Chronic ethanol treatment (CET), sufficient for decreasing long-term potentiation (LTP) in rats, also enhances 3H-GABA release from hippocampal slices in these same animals. The mechanism for an increase in GABA release may involve changes in presynaptic receptors. Therefore, we characterized presynaptic autoreceptor modulation of 3H-GABA release in hippocampal slices from control and CET rats. The effects of a GABAB receptor agonist (baclofen) and antagonist [2-hydroxy (OH)-saclofen] were tested for their ability to modulate electrically stimulated 3H-GABA release from superfused hippocampal slices. Baclofen decreased stimulated release in a dose-dependent manner and 2-OH-saclofen increased release consistent with the existence of presynaptic GABAB autoreceptors in hippocampus. The GABAA antagonist bicuculline did not significantly modulate basal or stimulated release. When the effects of baclofen and 2-OH-saclofen were measured in animals 48 hr after withdrawal from CET, presynaptic modulation of release by baclofen and 2-OH-saclofen was decreased. In addition, we examined the density of 3H-baclofen and 3H-bicuculline binding in the hippocampal formation using quantitative autoradiographic techniques. We found that the density of 3H-baclofen binding sites was not affected by CET, whereas the density of 3H-bicuculline binding sites was increased by 28% in ethanol-treated rats. These data may explain how CET increases presynaptic regulation of GABA release from hippocampus that may contribute to the decrease in LTP seen in rats after CET.
Perturbation of Organogenesis by the Herbicide Atrazine in the Amphibian Xenopus Laevis

BackgroundExposure to anthropogenic chemicals during development can disrupt the morphogenesis of organ systems. Use of the herbicide atrazine has been debated in recent years because of its implic...
A dipterid dipnoan from the Middle Devonian of Michigan, U.S.A.

ABSTRACT Chirodipterus onawayensis n. sp. is described from the Middle Devonian of northern Michigan. It differs from other species of Chirodipterus in details of the cheek bones, small size of the orbit, and elongation of the prepineal region of the skull. Chirodipterus is distinguished from Dipterus by the arrangement of bones on the side of the head rather than by propotions of the snout (cf. Miles, 1977).
Frequent ED users: patterns of use over time.

Abstract The objective of this study was to examine the pattern of emergency department (ED) use by frequent ED users over time. This study was a retrospective study of adults with more than 10 visits to a university hospital ED from 890 through 791. ED visits of this cohort to all hospitals in the metropolitan area were followed for 3 years. Records were reviewed for the etiology of each patient's ED visits. This cohort was comprised of 76 patients making 1,119 (1.9%) of the total 59,051 ED visits. Thirty-five of the 76 (46%) were frequent ED users in only the initial year. Thirteen of the 76 (17%) made more than 10 visits in all 4 years. The remainder had sporadic episodes of ED use. Thirty-five (46%) were evaluated at three or more EDs in years in which they were frequent users. Forty-two (55%) had a medical problem for the cause of the majority of their ED visits. Fifty-eight percent of patients making more than 10 visits in more than 1 year had psychiatric or substance abuse problems. The pattern of ED use in this cohort changed over time and was influenced by substance abuse and psychiatric problems. These data suggest that most patients do not remain frequent ED users over time.
RESEARCH NOTE ON HIGH SCHOOL SPECTATOR SPORTS PREFERENCES OF HIGH SCHOOL STUDENTS.

High school spectator sports preferences of high school students were ascertained by national administration of a questionnaire to 2000 snldents (964 boys and 1036 girls) representative of the national high school student pop~ilation (Blumenfeld, Franklin, & Rernmers, 1962 ) . In response to the question, "Which one of the following (11 sports commonly found in high school athletic competition) is your favorite high school sporting event co attend, watch on TV, or listen to on the radio?'., the sample indicated basketball (36%), football (31%), and baseball ( 10% ) as the most popular.:' Of the minor sports, swimming and wrestling were the most popular (5% each). Tests of the significance of the difference between these obtained percentages by means of the z statistic yielded values beyond the .O1 level. Preference order for boys was foocball (39%), baskecball (27% ), and baseball ( 13% ) ; preference order for girls was basketball (45% ), football (24%), and baseball (7% ). Differences between sexes were significant (p < .01). Over all 11 alcernatives, rho berween preferences of boys and girls was .80. The over-all preference order of high school spectator sports was baskecball, football, and baseball. (Note that baseball's being the national pastime notwithstanding, high school students preferred baskecball and football as a higli school spectator sport.) Boys preferred foocball, baskecball, and baseball; girls preferred basketball, foocball, and baseball. Basketball was more popular among girls; football and baseball were more popular among boys.
SGLT1, a novel cardiac glucose transporter, mediates increased glucose uptake in PRKAG2 cardiomyopathy

Human mutations in the gene PRKAG2 encoding the gamma2 subunit of AMP-activated protein kinase (AMPK) cause a glycogen storage cardiomyopathy. Transgenic mice (TG(T400N)) with the human T400N mutation exhibit inappropriate activation of AMPK and consequent glycogen storage in the heart. Although increased glucose uptake and activation of glycogen synthesis have been documented in PRKAG2 cardiomyopathy, the mechanism of increased glucose uptake has been uncertain. Wildtype (WT), TG(T400N), and TG(alpha2DN) (carrying a dominant negative, kinase dead alpha2 catalytic subunit of AMPK) mice were studied at ages 2-8 weeks. Cardiac mRNA expression of sodium-dependent glucose transporter 1 (SGLT1), but not facilitated-diffusion glucose transporter 1 (GLUT1) or GLUT4, was increased approximately 5- to 7-fold in TG(T400N) mice relative to WT. SGLT1 protein was similarly increased at the cardiac myocyte sarcolemma in TG(T400N) mice. Phlorizin, a specific SGLT1 inhibitor, attenuated cardiac glucose uptake in TG(T400N) mice by approximately 40%, but not in WT mice. Chronic phlorizin treatment reduced cardiac glycogen content by approximately 25% in TG(T400N) mice. AICAR, an AMPK activator, increased cardiac SGLT1 mRNA expression approximately 3-fold in WT mice. Relative to TG(T400N) mice, double transgenic (TG(T400N)/TG(alpha2DN)) mice had decreased ( approximately 50%) cardiac glucose uptake and decreased (approximately 70%) cardiac SGLT1 expression. TG(T400N) hearts had increased binding activity of the transcription factors HNF-1 and Sp1 to the promoter of the gene encoding SGLT1. Our data suggest that upregulation of cardiac SGLT1 is responsible for increased cardiac glucose uptake in the TG(T400N) mouse. Increased AMPK activity leads to upregulation of SGLT1, which in turn mediates increased cardiac glucose uptake.
COMPARISON OF BACTERICIDAL AND HEMOLYTIC SERUM SYSTEMS. I. INHIBITORY EFFECTS OF NORMAL HUMAN SERUM FRACTIONS.

SummaryWhen each of 32 different fractions, obtained from a human serum pool by electrophoresis, was added either to a bactericidal or a hemolytic serum reaction, inhibitory effects were found to be produced by some of the fractions. The bactericidal reaction, employing components present in “normal” human serum, was significantly inhibited by an excess of γ-globulins, and the hemolytic reaction by an excess of β-globulins. Inhibition of both reactions was also produced by an excess of serum fractions having the electrophoretic mobility of albumins. These findings are discussed in relation to quantitative and possibly qualitative differences in the serum components required for the bactericidal and hemolytic activities of serum.
Current Uncertainty in the Ratio of Active-to-Passive Gravitational Mass

The sensitivity of Kreuzer's experiment to a difference in active-to-passive mass ratios, $\frac{\ensuremath{\Delta}\ensuremath{\eta}}{\ensuremath{\eta}}$, is calculated on the basis of design specifications. This provides an independent means for determining the experiment sensitivity not subject to the criticisms directed toward the original evaluation. The sensitivity is found to be $\frac{(\frac{\ensuremath{\Delta}\ensuremath{\eta}}{\ensuremath{\eta}})}{S(0)}=1.9\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$, where $S(0)$ is the signal recorded by the apparatus due to nonzero $\frac{\ensuremath{\Delta}\ensuremath{\eta}}{\ensuremath{\eta}}$. This result is in substantial agreement with the original results.
On the Observed Robustness of Disturbance-Observers; A Technical Explanation and Simulation Validation

This paper examines the ability of a real-time "disturbance-observer" to adapt-to and closely estimate the time-behavior of a disturbance-input w(t) (and of it's state-vector z(t)) even when the actual w(t) time-behavior deviates from the observer's "internal-copy" of the nominal/predicted w(t)-behavior. By means of technical explanations and confirming simulation studies of numerical examples, the disturbance- observer's adaptive ability is explained in terms-of the underlying spline-model used to derive the disturbance state-model and the intrinsic dynamic characteristics of a state-observer.
The Entrance Boundary of the Multiplicative Coalescent

The multiplicative coalescent $X(t)$ is a $l^2$-valued Markov process representing coalescence of clusters of mass, where each pair of clusters merges at rate proportional to product of masses. From random graph asymptotics it is known (Aldous (1997)) that there exists a standard version of this process starting with infinitesimally small clusters at time $- \infty$. In this paper, stochastic calculus techniques are used to describe all versions $(X(t);- \infty < t < \infty)$ of the multiplicative coalescent. Roughly, an extreme version is specified by translation and scale parameters, and a vector $c \in l^3$ of relative sizes of large clusters at time $- \infty$. Such a version may be characterized in three ways: via its $t \to - \infty$ behavior, via a representation of the marginal distribution $X(t)$ in terms of excursion-lengths of a Levy-type process, or via a weak limit of processes derived from the standard version via a "coloring" construction.
Do Not Judge a Kidney by Its Pelvis: A Rare Case of an Unobstructed Dilated Renal Pelvis

We present a rare case of an unobstructed dilated renal pelvis in a newborn female. Prenatal imaging documented a large abdominal cyst in a stable fetus. Postnatal imaging confirmed persistence of this large cyst but with an unclear etiology. The child was taken to surgery by the pediatric surgeons with concern for a possible harmful nonurologic diagnosis. Intraoperative findings were that of a severely dilated renal pelvis; however, in the absence of an expected ureteropelvic junction obstruction. Reduction pyeloplasty without interference of the ureteropelvic junction proved successful.
Linear, Deterministic, and Order-Invariant Initialization Methods for the K-Means Clustering Algorithm

Over the past five decades, k-means has become the clustering algorithm of choice in many application domains primarily due to its simplicity, time/space efficiency, and invariance to the ordering of the data points. Unfortunately, the algorithm’s sensitivity to the initial selection of the cluster centers remains to be its most serious drawback. Numerous initialization methods have been proposed to address this drawback. Many of these methods, however, have time complexity superlinear in the number of data points, which makes them impractical for large data sets. On the other hand, linear methods are often random and/or sensitive to the ordering of the data points. These methods are generally unreliable in that the quality of their results is unpredictable. Therefore, it is common practice to perform multiple runs of such methods and take the output of the run that produces the best results. Such a practice, however, greatly increases the computational requirements of the otherwise highly efficient k-means algorithm. In this chapter, we investigate the empirical performance of six linear, deterministic (non-random), and order-invariant k-means initialization methods on a large and diverse collection of data sets from the UCI Machine Learning Repository. The results demonstrate that two relatively unknown hierarchical initialization methods due to Su and Dy outperform the remaining four methods with respect to two objective effectiveness criteria. In addition, a recent method due to Erisoglu et al. performs surprisingly poorly.
Control of Three-phase Power Factor Corrected Rectifier in Balanced and Unbalanced Systems

One-cycle Control is a unified constant-frequency control scheme, with which the three-phase rectifier achieves unity power factor and low THD. Previous research has been conducted on the OCC controlled rectifier in both balanced and unbalanced system. The analysis of the rectifier in unbalanced system indicates that although the controller is proposed for balanced system, it also works for the unbalanced system, and the phase currents will be proportional to the non-zero sequence phase voltages under unbalanced conditions. The result is satisfying since the current waveform quality is high and the source voltages have the same load stresses. However, there are still two limitations for the present OCC controller in unbalanced system: first, minimum switching losses can not be ensured, which is contradictory to the vector control goal; second, the present OCC controller will not be able to handle the extreme unbalanced system where one phase voltage is entirely zero. In light of these, this paper aims to improve the present OCC controller's performance in unbalanced system. By utilizing the non-zero sequence phase voltages for region selection, both limitations are eliminated. The proposed OCC vector controller can cope with all the system conditions, with switching losses always minimized. A 1kW experimental prototype has been built to verify the proposed controller.
Atmospheric science: African dust in Florida clouds

Satellites and numerical models now track the intercontinental transport of airborne particles. Better knowledge of cloud physics will be necessary to gauge the effects on clouds and rainfall patterns.