cssi/SciSciGPT-SciSciNet huggingface dataset:
On the existence of rook equivalent t -cores

For a positive integer t, a partition is said to be a t-core if each of the hook numbers from its Ferrers-Young diagram is not divisible by t. In 1998, Haglund et al. (J. Combin. Theory Ser. A 84 (1) (1998) 9) proved that if t = 2, 3, or 4, then two distinct t-cores are rook equivalent if and only if they are conjugates. In contrast to this theorem, they conjectured that if t ≥ 5, then there exists a constant N(t) such that for every positive integer n ≥ N(t), there exist two distinct rook equivalent t-cores of n which are not conjugate. Here this conjecture is proven for t ≥ 12 with N(t) = 4 in all cases.
Spontaneous Proliferation of HTLV-II-Infected Peripheral Blood Lymphocytes: HLA-DR-Driven, IL-2-Dependent Response

Peripheral blood lymphocytes obtained from HTLV-II-infected persons (n = 13) and cultured in the absence of exogenous stimulator demonstrated augmented spontaneous proliferation (17,672 +/- 5,498 cpm) when compared with cells from healthy donors (1,921 +/- 1,306 cpm). Removal of non-T population did not abrogate the proliferative response of patients' PBMC, suggesting that the proliferation is not related to the autologous mixed lymphocyte reaction. Addition of recombinant interleukin-2 (rIL-2; 0.1 U/ml) to spontaneously proliferating cultures from HTLV-II-infected persons resulted in a 3- to 4-fold increase in proliferation (61,985 +/- 16,003); in contrast, PBMC from controls demonstrated 38- to 42-fold increase in their proliferative capacity in response to rIL-2 (77,256 +/- 13,044). Antibodies to both IL-2 receptor and HLA-DR were able to inhibit the spontaneous proliferation of PBMC from HTLV-II-infected persons in a dose-dependent manner. Furthermore, addition of cyclosporin A, which preferentially blocks accumulation of IL-2 mRNA, also inhibited spontaneous proliferation in a dose-dependent manner. These observations suggest that the spontaneous proliferation of HTLV-II-infected PBMC is at least in part an HLA-DR-driven, IL-2-dependent event, which is not analogous to the AMLR.
Protein kinase C: cellular target of the second messenger arachidonic acid?

Protein kinase C (PKC) is a family of serine/threonine protein kinases which play a critical role in signal transduction, tumor promotion and cell regulation. Initially characterized as a calcium-and phospholipid-dependent protein kinase, early studies demonstrated that PKC was activated potently by diacylglycerol (DAG), a product of phosphatidylinositol turnover, establishing a role for PKC in signal transduction. More recently, PKC has been shown to be activated by free fatty acids, both in vitro and in vivo. Since arachidonic acid and other free fatty acids have been characterized as second messengers, this connection has strengthened the role of PKC in signal transduction. The activation of PKC by the classical activators of PKC, phosphatidylserine (PS), DAG and calcium has been reviewed recently (1-3). This review will focus on the activation of PKC by free fatty acids in vitro and in vivo. We will begin by presenting an overview of PKC to (1) review classical activation of PKC (by PS/DAG) to use as a point of reference and comparison to fatty acid-induced activation and (2) elaborate on the methodology currently used to study PKC including the advantages and disadvantages of these approaches. We will then review the activation of PKC by free fatty acids both in vitro and in vivo. Finally, we will end by presenting a model for free fatty acid activation of PKC.
Thermally Stable Nanocrystalline TiO2 Photocatalysts Synthesized via Sol−Gel Methods Modified with Ionic Liquid and Surfactant Molecules

Recently, sol−gel methods employing ionic liquids (ILs) have shown significant implications for the synthesis of well-defined nanostructured inorganic materials. Herein, we synthesized nanocrystalline TiO2 particles via an alkoxide sol−gel method employing a water-immiscible room temperature IL (1-butyl-3-methylimidazolium hexafluorophosphate, [bmim][PF6]) as a new solvent medium and further modified with nonionic surfactant (polyoxyethylenesorbitan monooleate) as a pore templating material. Detailed information on the preparative method, synthesis route and mechanism, crystallographic and structural properties, and photocatalytic activity of the TiO2 particles is described. The possible rationale for the formation of nanocrystalline TiO2 particles with high surface area and activity is discussed with respect to the special characteristics of [bmim][PF6] as well as the role of the surfactant self-assembly in the sol−gel network. Due to its capping effect and water immiscibility, the use of [bmim][PF6] in ...
Species richness and distribution of ferns along an elevational gradient in Costa Rica

To better understand changes in the distribution and diversity within plant functional types along an elevational gradient and the potential mechanisms driving such changes, we studied species richness of ferns at six elevations along a forested elevational gradient in Costa Rica, from La Selva Biological Station at 30 m a.s.l. up the slopes of Volcan Barva to 2960 m a.s.l. Among the samples from all the sites combined, we found 264 species from 60 genera. Sixty-nine species were terrestrial, 113 were canopy epiphytes, and 121 were low-trunk epiphytes. Only one species occupied both canopy and terrestrial habitats at any of the study sites. Overlap of canopy and low-trunk species composition was relatively low (18%), and lower still was the overlap of terrestrial and low-trunk species (12%). Total species richness peaked at the 1000-m site for canopy and low-trunk epiphytic species. In contrast, the richness of terrestrial species rose to a mid-elevation maximum and remained relatively constant at higher elevations. In an effort to explain elevational patterns of species richness, we examined mean annual rainfall and temperature, light intensities in the canopy and at ground level, and the mid-domain effect. Of the explanatory factors examined, the mid-domain effect accounted for most of the elevational pattern. We found little evidence that environmental gradients drive patterns of fern species richness on this spatial scale.
Modeling and control of microelectronics materials processing

Abstract Major advances in modeling and control will be required to meet future technical challenges in microelectronics manufacturing. This paper reviews the recent applications of fundamental mathematical modeling to unit operations such as crystal growth, lithography, chemical vapor deposition and plasma etching, where there have been some notable successes. Important characteristics of these processes are identified, and the evolution of the standard multiwafer reactor to single wafer reactors processing larger wafers is discussed. The implementation of closed-loop control on key unit operations in microelectronics manufacturing has been extremely limited due to a lack of suitable on-line measurements. There remains considerable promise for application of modern control and optimization techniques in manufacture of integrated circuits.
Excess density compensation of island herpetofaunal assemblages

Aim Some species reach extraordinary densities on islands. Island assemblages have fewer species, however, and it is possible that island species differ from their mainland counterparts in average mass. Island assemblages could be partitioned differently (fewer species or smaller individuals) from mainland sites without differing in aggregate biomass (density compensation). Our objective was to determine the generality of excess density compensation in island herpetofaunal assemblages. Location Our bounded removal plot data were obtained from Pacific Island sites (Guam, Saipan and Rota), the West Indies (British Virgin Islands), and the Indian Ocean (Ile aux Aigrettes off Mauritius). The literature values were taken from several locales. Other island locations included Barro Colorado Island, Bonaire, Borneo, Philippine Islands, Seychelle Islands, Barrow Island (Australia), North Brother Island (New Zealand), Dominica and Puerto Rico. Mainland sites included Costa Rica, Ivory Coast, Cameroon, Australia, Thailand, Peru, Brazil, Panama and the USA. Method We added our thirty-nine bounded total removal plots from sixteen island habitats to fifteen literature records to obtain seventy-five venues with estimable density and biomass of arboreal or terrestrial herpetofaunal assemblages. These biomass estimates were evaluated geographically and in relation to sampling method, insularity, latitude, disturbance regime, seasonality, community richness, vegetative structure and climate. Direct data on trophic interactions (food availability, parasitism and predation pressure) were generally unavailable. Sampling problems were frequent for arboreal, cryptic and evasive species. Results and main conclusions We found strong evidence that herpetofaunal assemblages on small islands (mostly lizards) exhibit a much greater aggregate density of biomass (kg ha−1) than those of larger islands or mainland assemblages (small islands show excess density compensation). High aggregate biomass density was more strongly associated with the degree of species impoverishment on islands than it was on island area or insularity per se. High aggregate biomass density was not strongly associated with latitude, precipitation, canopy height or a variety of other physical characteristics of the study sites. The association between high aggregate biomass density and species-poor islands is consistent with the effects of a reduced suite of predators on depauperate islands, but other features may also contribute to excess density compensation.
TRH-like immunoreactivity in rat pancreas and eye, bovine and sheep pineals, and human placenta: Non-identity with synthetic Pyroglu-His-Pro-NH2 (TRH)

Abstract Extracts from albino rat eyes and pancreas, bovine and sheep pineals and human placenta containing TRH-like immunoreactivity were chromatographed on silica-gel plates. Comparison of elution profiles for TRH-like immunoreactivity with that of TRH revealed the presence of substances other than TRH in these samples. Chromatography of TRH-like immunoreactivity obtained fromRana pipiens skin eluted in two solvent systems produced elution profiles identical with that of synthetic Pyroglu-His-Pro-NH2 consistent with reports that frog skin contains large quantities of TRH. Implications of these findings are discussed.
Misalignment-insensitive wireless power transfer via strongly coupled magnetic resonance principles

An efficient wireless power transfer (WPT) of strongly coupled magnetic resonance (SCMR) with loops is shown here. This paper shows an optimal 3D loop design for SCMR systems, that is insensitive to misalignment, and exhibits higher efficiency than typical SCMR devices.
A murine osteoblast cell line (MC3T3) produces A soluble elastogenic compound

Elastofibromas are localized proliferations of mesenchymal cells that produce an exuberant amount of elastin-rich extracellular matrix. Recently periosteal fibroblasts have been proposed to be the proliferating cell. The hypothesis has been tested that osteocytes or osteoblasts contribute to the formation of elastofibromas by secreting a compound(s) that enhances elastin production. Media conditioned by murine calvarial osteoblasts (MC3T3) increased tropoelastin synthesis in bovine ligamentum nuchae fibroblasts. Addition of MC3T3-conditioned medium to bovine ligamentum nuchae fibroblast cultures produced a two-fold increase in tropoelastin RNA. The maximal increase in tropoelastin RNA was between 16 and 24 h; tropoelastin mRNA had returned to control values by 40 h. A similar increase in tropoelastin protein production was detected. The soluble elastogenic compound was neither interleukin-1 (IL-1) nor IL-6. These results support the hypothesis that an interaction between bone and perosteum may be involved in the formation of elastofibromas.
Enhanced Backscattering near 180° for Energetic Ions in Solids

A new ion scattering effect which enhances backscattering yields near 180° has been recently reported. A computer program which simulates this scattering effect is discussed and the results compared with measurements. Both the angular distribution and depth profiles of the backscattered yield enhancements are compared. These comparisons verify the proposed explanation for the new scattering phenomena and a tentative explanation is offered for the small discrepancies which exist.
Temperature levels and periods of sex determination during incubation of eggs of Chelydra serpentina.

Eggs of Chelydra serpentina were shifted during incubation between the female producing temperatures of 20°C or 30°C and the male producing temperature of 26°C. In the 20°C and 26°C combination, the stages during which incubation temperature determined sex were stage 14 through stage 16 (stages of normal series, Yntema, '68). In the 30°C and 26°C combination, the temperature sensitive stages for sex determination were stage 14 through stage 19. Incubation at 26°C throughout this period was needed to produce all males. Incubation at 30°C during either the first or second half of the period produced nearly all females; shorter periods of incubation at 30°C were more effective in producing females during the second half of the sensitive period. In the 20°C and 26°C combination, incubation at 20°C or 26°C for parts of the sensitive period produced both males and females. In three of the 57 clutches of eggs used in the experiments, incidence of females was atypically high.
An Implementation of the Model Elimination Proof Procedure

The model elimination (ME) and resolution algorithms for mechanical theorem-proving were implemented so as to maximize shared features. The identical data structures and large amount of common programming permit meaningful comparisons when the two programs are run on standard problems. ME does better on some classes of problems, and resolution better on others. The depth-first search strategy used in this ME implementation affects the performance profoundly. Other novel features in the implementation are new control parameters to govern extensions, and modified rules for generating and rejecting chains. The resolution program incorporates unit preference and set-of-support. An appendix reproduces the steps of a machine-derived ME refutation.
Mental health: drop ideological baggage in favour of best tools

A News Feature in the 10 July issue reported on differences between geneticists and neuroscientists concerning the interpretation of the genetics of mental illness (The brains of the family, Nature 454, 154–157; 2008). But are both groups overlooking significant factors more directly relevant to human suffering? The Correspondence columns this week broaden the debate to consider environmental factors, which have been linked to conditions such as schizophrenia, and to ask whether textbook definitions of psychiatric disorders are merely arbitrary checklists.
Electric Field Gradient in the Arsenic Structure

The electric field gradients at an ion site per monopole moment and per quadrupole moment of all other ions are calculated for a body-centered rhombohedral structure over a wide range of parameter values. Similar calculations specifically applicable to the elements arsenic, antimony, and bismuth, for which the body-centered ion is slightly displaced, are also performed.
A reference standard for the development of acoustic emission pipeline leak detection techniques

Abstract A reference standard was constructed for setting up and evaluating AE equipment to be used in pipeline leak detection. The reference standard comprises a short length of 2-inch diameter piping with facilities for introducing several kinds of controlled leaks. The reference standard proved very valuable not only for checking out equipment, but also for characterizing source mechanisms as part of an integrated approach to quantitative AE leak detection/location technology. The effects of pressure and air injection were measured for thread leaks on the order of 0.1 gal h −1 , a leakage rate that is important in the context of environmental protection regulations. Taking this knowledge to the field, a thread leak of only 0.014 gal h −1 was successfully detected and located by injecting nitrogen into the line at 25 psi. This leak was located with 1 foot accuracy, using two different location techniques and 25-foot sensor spacing. It is envisioned that in the future, AE inspectors in the field will make systematic use of several two-phase flow processes and soil enhancement mechanisms that are being characterized by means of this new reference standard.
Ignition behavior of a multicomponent fuel spray

Ignition characteristics of multicomponent fuel sprays are studied. Three subsets of equations, the gas-phase, the liquid-phase, and the droplet equations, are solved by a hybrid Eulerian-Lagrangian, explicit-implicit method. Major features of the ignition model are that a zero heat-flux criterion is used to define ignition, a global one-step reaction scheme with nonunity exponents of fuel and oxygen is employed for a multifuel system, and the transient thermal and composition fields inside the droplet are resolved via a diffusion-limit model. Monodisperse and polydisperse size distributions are considered. The results are presented for a bicomponent fuel spray. The ignition behavior exhibits a strong sensitivity to the initial fuel composition. The presence of a volatile component, even in small amounts, can greatly improve the ignitability of nonvolatile fuel sprays. The relative enhancement in ignitability depends strongly on the droplet size, volatility differential, hot wall temperature, and, to a lesser degree, on the equivalence ratio. The results are significant from a practical point of view as the concept may be used to improve the ignitability of liquid fuel sprays.
Elastic Green’s Functions for a Specific Graded Material With a Quadratic Variation of Elasticity

In this work, Green’s functions for unbounded elastic domain in a functionally graded material with a quadratic variation of elastic moduli and constant Poisson’s ratio of 0.25 are derived for both two-dimensional (2D) and three-dimensional (3D) cases. The displacement fields caused by a point force are derived using the logarithmic potential and the Kelvin solution for 2D and 3D cases, respectively. For a circular (2D) or spherical (3D) bounded domain, analytical solutions are provided by superposing the above solutions and corresponding elastic general solutions. This closed form solution is valuable for elastic analysis with material stiffness variations caused by temperature, moisture, aging effect, or material composition, and it can be used to perform early stage verification of more complex models of functionally graded materials. Comparison of theoretical solution and finite element method results demonstrates the application and accuracy of this solution.
The Burgers vector and the flow of screw and edge dislocations in finite-deformation single-crystal plasticity

Abstract We consider finite plasticity based on the decomposition F = F e F p of the deformation gradient F into elastic and plastic distortions F e and F p ( det F p = 1 ) . Within this framework the macroscopic Burgers vector may be characterized by the tensor field G = F p Curl F p . We derive a natural convected rate for G associated with evolution of F p and as our main result show that, for a single-crystal, • temporal changes in G —as characterized by its convected time derivative—may be decomposed into temporal changes in distributions of screw and edge dislocations on the individual slip systems. We discuss defect energies dependent on the densities of these distributions and show that corresponding thermodynamic forces are macroscopic counterparts of classical Peach–Koehler forces.
Automatic classification of motor unit potentials in surface EMG recorded from thenar muscles paralyzed by spinal cord injury

Involuntary electromyographic (EMG) activity has only been analyzed in the paralyzed thenar muscles of spinal cord injured (SCI) subjects for several minutes. It is unknown if this motor unit activity is ongoing. Longer duration EMG recordings can investigate the biological significance of this activity. Since no software is currently capable of classifying 24h of EMG data at a single motor unit level, the goal of this research was to devise an algorithm that would automatically classify motor unit potentials by tracking the firing behavior of motor units over 24h. Two channels of thenar muscle surface EMG were recorded over 24h from seven SCI subjects with a chronic cervical level injury using a custom data logging device with custom software. The automatic motor unit classification algorithm developed here employed multiple passes through these 24-h EMG recordings to segment, cluster, form global templates and classify motor unit potentials, including superimposed potentials. The classification algorithm was able to track an average of 19 global classes in seven 24-h recordings with a mean (+/-SE) accuracy of 89.9% (+/-0.98%) and classify potentials from these individual motor units with a mean accuracy of 90.3% (+/-0.97%). The algorithm could analyze 24h of data in 2-3 weeks with minimal input from a person, while a human operator was estimated to take more than 2 years. This automatic method could be applied clinically to investigate the fasciculation potentials often found in motoneuron disorders such as amyotrophic lateral sclerosis.
Consequences of adolescent or adult ethanol exposure on tone and context fear retention: effects of an acute ethanol challenge during conditioning.

Background An acute ethanol (EtOH) challenge prior to fear conditioning typically disrupts fear retention to contextual cues to a greater degree than fear retention to a discrete tone cue, and adolescent rats are less sensitive than adults to these EtOH-induced disruptions of context fear memory. Given that some research suggests that repeated EtOH exposure during adolescence may “lock-in” adolescent-typical EtOH sensitivity into adulthood, the purpose of this study was to determine whether adults exposed to EtOH as adolescents would be less sensitive to EtOH-induced disruptions of context fear. Methods Male Sprague–Dawley rats were given 4 g/kg intragastric EtOH (25% v/v) or water every 48 hours for a total of 11 exposures during adolescence (postnatal day [P] 28 to 48) or adulthood (P70–90). After a 22-day non-EtOH period, animals were acutely challenged with 1 g/kg intraperitoneal EtOH or saline 10 minutes prior to tone or context (noncued) fear conditioning. Tone and context fear retention was subsequently examined. Results Regardless of age or exposure history, typical deficits in context fear retention were evident after EtOH challenge during conditioning. Similarly, tone fear retention was disrupted in all animals that were trained in the presence of EtOH, which was somewhat surprising given the relative resistance of tone fear retention to an acute EtOH challenge. Conclusions These results do not support the notion of a “lock-in” of adolescent-typical EtOH sensitivity as there was no influence of exposure age on sensitivity to the disruptive effects of an acute EtOH challenge. Thus, it appears that not all adolescent-like EtOH sensitivities persist into adulthood after prior EtOH exposure during adolescence.
The effects of chromosomal rearrangements on the zeste-white interaction in Drosophila melanogaster.

Three gene systems have been shown to exhibit proximity-dependent phenotypes in Drosophila melanogaster : bithorax ( BX-C ), decapentaplegic ( DPP-C ) and white ( w ). In structurally homozygous genotypes, specific allelic combinations at these loci exhibit one phenotype, while in certain rearrangement heterozygotes the same allelic combinations exhibit dramatically different phenotypes. These observations have led to the suggestion that, through the process of somatic chromosome pairing, such loci are brought into sufficient proximity to permit effective passage of molecular information between homologues; rearrangement heterozygosity would then displace the homologues relative to one another such that this trans -communication is obviated. The genetic properties of the proximity-dependent allelic complementation (termed transvection effects) at the BX-C and DPP-C , are quite similar. Chromosomal rearrangements which disrupt transvection possess a breakpoint in a particular segment of the chromosome arm bearing the transvection-sensitive gene (arm 2 L for the DDP-C and 3 R for the BX-C ); this segment of each arm has been termed the critical region by Lewis (1954). As determined by cytogenetic analysis of transvection-disrupting rearrangements, the critical regions for the BX-C and DDP-C transvection effects extend proximally from these loci for several hundred polytene chromosome bands (Lewis 1954; Gelbart 1982). The interaction between the zeste and white loci appears to depend upon the proximity of the two w+ alleles. By use of insertional duplications, displacement of w+ homologues has been shown to interfere with the zeste-white interaction. In contrast to transvection at bithorax and decapentaplegic , however, only breakpoints in the immediate vicinity of the white locus can disrupt the zeste-white interaction (Gans 1953; Green 1967; Gelbart 1971; this report). In this report, we investigate the basis for the difference in the size of the BX-C and DPP-C critical regions from that of white . We test and eliminate the possibility that the difference is due to the presence near the white locus of a site which mediates somatic chromosome pairing. Rather, our evidence strongly suggests that the zeste-white interaction is, at the phenotypic level, much less sensitive to displacement of the homologous genes than is transvection at either the BX-C or DPP-C . We also show that many of the breakpoints in the vicinity of the white locus do not behave as if they are disrupting a critical region for somatic chromosome pairing. Given these results, we suggest that the zeste-white interaction and transvection are two different proximity-dependent phenomena.
Adaptive High-Speed Optical Transceivers Using a Dual Electrode Modulator

Future military communication systems will require highly agile terminals that can support the growing bandwidth needs of the warfighter while providing connectivity in the dynamic environment of a mobile wireless communication network. While todays high speed optical communication links are typically engineered with a fixed design, future systems should be adaptive to optimize system performance in an ever changing communication channel. In this paper, we propose a highly adaptive optical transceiver based on a dual-electrode modulator. This architecture drastically reduces the complexity in the optical path of the system compared to previous designs. The presented transceiver can support rate adjustable Return-to-zero On-Off Key (RZ-OOK), rate adjustable Binary Pulse Position Modulation (BPPM), and rate adjustable Return-to-Zero Differential Phase-Shift-Keying (RZ-DPSK) modulation formats. Experimental results showing the performance of a prototype system are presented.
Influence of metal surface finishing on porcelain porosity and beam failure loads at the metal-ceramic interface

Abstract Statement of the Problem. Investigators suggest that metals should be finished in 1 direction before porcelain application to minimize metal irregularities and trapped contaminants. These irregularities are thought to be focal points for porosity and crack propagation. Purpose. This study investigated the influence of metal finishing and sandblasting on (1) porosity production at the porcelain-metal interface, and (2) porcelain-metal beam failure load. Material and Methods. Eighty cast metal samples were divided into 4 test groups: (A) bidirectional finish/sandblasting; (B) unidirectional finish/sandblasting (C) bidirectional finish only; and (D) unidirectional finish only. The porcelain applied was 1.5 mm thick. Samples were sectioned longitudinally. Half of the samples were subjected to a 3-point flexural test. The remaining samples were sectioned into 4 slices and were examined with a light microscope (×500). Number and diameter of porosities at the metal-porcelain interface were recorded. Results. Mean loads at failure (lbs) were as follows: A, 11.1 ± 1.3 (5.03 ± 0.58 Kg); B, 11.2 ± 1.7 (5.08 ± 0.77 Kg); C, 4.0 ± 1.8 (1.81 ± 0.81 Kg); and D, 5.0 ± 2.1 (2.26 ± 0.95 Kg). Groups A and B were significantly different from groups C and D ( P Conclusion. Direction of metal finishing did not affect the porosity number and size at the ceramometal interface or the beam failure loads. Sandblasting increased the beam failure loads. Nonsandblasted samples showed detachment of the porcelain from the metal. (J Prosthet Dent 2000;84:309-17.)
Prepayment Penalty as a Screening Mechanism for Default and Prepayment Risks

The objective of this article is to offer a theoretical model of asymmetric information to analyze the screening role of prepayment penalty. We consider both default risk and prepayment risk. What makes the role of prepayment penalty interesting and more complicated is that a borrower's contract choice could send conflicting signals to the lender about that borrower's default and prepayment risk type. This is different from earlier theoretical models of mortgage choice under asymmetric information where a certain aspect of the contract (e.g., discount points or loan-to-value ratio) is explored as a screening mechanism for a single risk dimension (default risk or prepayment risk) of the borrower type. We show the existence of separating equilibria where different default and prepayment risk types choose contracts with different combinations of prepayment penalty and interest rate. For certain parameter combinations, the model also generates a pooling equilibrium where all borrower types obtain the same contract. Our analysis could offer a partial explanation for the observation that contracts with prepayment penalties are a lot less prevalent than contracts with points.
Release of Neurotransmitter Amino Acids from Synaptosomes: Enhancement of Calcium-Independent Efflux by Oleic and Arachidonic Acids

The release of preloaded [14C]neuroactive amino acids (glutamic acid, proline, gamma-aminobutyric acid) from rat brain synaptosomes can occur via a time-dependent, Ca2+-independent process. This Ca2+-independent efflux is increased by compounds that activate Na+ channels (veratridine, scorpion venoms), by the ionophore gramicidin D, and by low concentrations of unsaturated fatty acids (oleic acid and arachidonic acid). Saturated fatty acids have no effect on the efflux process. Neither saturated nor unsaturated fatty acids have an effect on the release of [14C]leucine, an amino acid not known to possess neurotransmitter properties. The increase in the efflux of neuroactive amino acids by oleic and arachidonic acids can also be demonstrated using synaptosomal membrane vesicles. Under conditions in which unsaturated free fatty acids enhance amino acid efflux, no effect on 22Na+ permeability is observed. Since Na+ permeability is not altered by fatty acids, the synaptosomes are not depolarized in their presence and, thus, the Na+ gradient can be assumed to be undisturbed. We conclude that unsaturated fatty acids represent a potentially important class of endogenous modulators of neuroactive amino acid transport in nerve endings and further postulate that their action is the result of an uncoupling of amino acid transport from the synaptosomal Na+ gradient.
A novel entropy estimator and its application to ICA

We present a new (differential) entropy estimator where the maximum entropy bound is used to approximate the entropy given the observations, and is computed using a numerical procedure. The resulting accurate estimate for the entropy is used to derive a new algorithm to perform independent component analysis (ICA). The new algorithm, ICA by entropy bound minimization (ICA-EBM), adopts a line search procedure, and initially uses updates that constrain the demixing matrix to be orthogonal for robust performance. We present simulation results that demonstrate the superior performance of ICA-EBM and its ability to match sources that come from a wide range of distributions.
Effect of dietary lactose on the productive performance of young Turkeys

SUMMARY Studies were conducted to assess the performance of turkeys fed diets containing lactose. Study 1 consisted of 96, mixed-sex turkey poults that were housed in battery cages and fed diets containing 0 (8% cornstarch), 0.5, 1, 2, 4, or 8% lactose from 0 to 6 wk. Study 2 used 360, mixed-sex turkey poults that were raised in floor pens and fed a commercial diet and diets containing 0 (4% starch), 0.5, 1, 2, or 4% lactose from 0 to 6 wk. Diets and water were offered ad libitum throughout both trials. The objectives were 1) to determine the effect of lactose on turkey performance and 2) to establish the optimum level for lactose inclusion in diets. In Study 1, feed intake, BW, fecal ammonia and nitrogen, and feed efficiency were determined. Diet composition, BW, feed intake, total body and carcass composition, cecal pH, volatile fatty acids (VFA) and lactic acid were measured in Study 2. Turkeys consuming the 4% lactose diet gained the most weight (P < 0.01) compared with other treatments in Study 1, and lactose improved feed efficiency. In Study 2, all lactose diets resulted in heavier BW (P < 0.05) compared with the commercial diet. Turkeys consuming diets with 0.5, 1, 2 or 4% lactose had less total body fat compared with turkeys consuming a commercial or 0% lactose diet (P < 0.05).
Autonomic characteristics of defensive hostility: reactivity and recovery to active and passive stressors.

The autonomic characteristics of hostility and defensiveness were assessed in 55 male undergraduates based on composite Cook Medley Hostility (Chost) and Marlowe Crowne Social Desirability (MC) scores to create 4 groups: Defensive Hostile (DH; high MC, high Chost), High Hostile (HH; low MC, high Chost), Defensive (Def; high MC, low Chost) and Low Hostile (LH; low MC, low Chost). All subjects engaged in a video game (VG) and hand cold pressor (CP) task. Cardiovascular responses in DH subjects were predicted to show enhanced sympathetic α and β-adrenergic activity and the least vagal control compared to others across tasks. DH and LH men showed significant heart rate reactivity to the CP task compared to HH men. LH men showed significant reductions in high frequency power (vagal assessment) to the tasks compared to HH men. Future studies may employ harassment techniques and include the factors of gender and ethnicity in their assessments. © 2007 Elsevier B.V. All rights reserved.
A lattice interpretation of group-centric collaboration with expedient insiders

For various reasons organizations need to collaborate with external consultants, e.g. domain specialists, on specific projects. Many security-oriented organizations deploy multi-level systems which enforce one directional information flow in a lattice of security labels. However, traditional lattice constructions are not suitable for accommodating external consultants, since such consultants are not “true insiders” but rather “expedient insiders” who should receive much more limited privileges than employees. An authorization model for group-centric collaboration with expedient insiders (GEI) has been recently proposed, wherein organizations create groups and replicate the organizational lattice with selected content for such collaborations [4]. Motivated by GEI, in this paper, we formulate a novel lattice construction wherein a new collaboration category is introduced for each new collaboration group, in a manner significantly different from the usual process of defining new security categories in a lattice. In particular, a collaboration category brings together only the required objects and users. We develop a formal model for lattices with collaborative compartments (LCC) comprising administrative and operational parts covering the life-cycle of such collaborations. We formally prove the equivalence of LCC and GEI, thereby precisely characterizing the information flow and security properties of GEI which heretofore had only been informally considered. This equivalence shows that GEI can be realized via LBAC with minimal operational disruptions.
Overdiagnosis of osteoporosis in children due to misinterpretation of dual-energy x-ray absorptiometry (DEXA).

Abstract Objective Dual-energy x-ray absorptiometry (DEXA) is increasingly used to evaluate children for osteoporosis. However, the interpretation of pediatric DEXA is complicated by growth and development. Because most DEXA scans are performed on adults, we hypothesized that physicians who interpret DEXA may not be aware of these pediatric issues, potentially leading to misdiagnosis. Study design Children (n = 34, aged 4-17 years) diagnosed with low bone mineral density (BMD) based on a DEXA scan were referred for possible inclusion in a childhood osteoporosis protocol. The referral DEXA scans were analyzed for accuracy. Results Thirty (88%) of the scans had at least one error in interpretation. The most frequent error (62%) was use of T-score (SD score compared with young adults) to diagnose osteoporosis, which is inappropriate for children. Other errors included use of a reference database that does not consider gender or ethnic differences (21%), incorrect bone map (21%), inattention to short stature (15%), and other measurement or statistical error (12%). After correcting for these errors, 53% had normal BMD, whereas only 26% retained the diagnosis of low BMD. The remaining 21% could not be given a definitive diagnosis. Conclusion In children, the diagnosis of osteoporosis is often due to misinterpretation of a DEXA scan.
The Microwave Power Module: a 'supercomponent' for radar transmitters

The Microwave Power Module (MPM) represents creative blending of concepts and techniques from solid-state and vacuum electronics that results in a 'supercomponent' with performance benefits not attainable from either technology alone. The MPM is suitable for a variety of applications ranging from communications through electronic warfare to where efficiency, wide instantaneous bandwidth, and low noise are required in moderate module powers of several tens to several hundreds of watts (average). This paper presents the MPM concept, describes the MPM program, and presents preliminary conclusions derived from several generic radar system point designs in which the MPM is, at the least, a viable alternative to existing and projected technologies and, at most, represents a point of departure for exciting radar system enhancements. >
Parturition and bed site selection of bighorn sheep at local and landscape scales

Selection of parturition sites by wild ungulates involves trade-offs between maximizing forage quality or availability and minimizing predation risk. Previous studies documenting critical lambing habitat of bighorn sheep (Ovis canadensis) have relied on visual observations that can lead to biased results. We used vaginal implant transmitters (VITs) and intensely monitored radiocollared females to 1) accurately identify parturition events for bighorn sheep; 2) quantify habitat selection for parturition events at the macro- and microhabitat scales; and 3) quantify habitat selection of neonate lamb (� 24hrold) bed sites at the microhabitat scale in the Black Hills, South Dakota. From 2010-2012, we documented 43 parturition and 47 lamb bed sites for microhabitat analysis, and incorporated an additional 28 capture sites where lambs were � 24hours old for macrohabitat analysis (n ¼71). We found females equipped with VITs increased our ability to identify parturition events 2-fold (67%) over intensely monitored radiocollared ewes (33%), and 82% (58/71) of parturition events occurred outside of previously delineated lambing habitat. Results of model-averaged generalized estimating equations revealed bighorn sheep females selected for relatively flat spaces within rugged terrain, areas that were close to perennial streams, south and west facing slopes, and against anthropogenic disturbance.At themicrohabitat scale, neonatelambs tended to select for greater cover in the uphill and downhill directions, and against north facing slopes. We hypothesize the patterns of selection we observed were related to predator-avoidance strategies and increased solar radiation. We recommend managers reassess designated critical lambing habitat previously defined by visual observations, or consider more broad-scale temporal closures to protect parturient habitat. 2015 The Wildlife Society.
Structural changes that occur upon photolysis of the Fe(II)(a3)-CO complex in the cytochrome ba(3)-oxidase of Thermus thermophilus: A combined X-ray crystallographic and infrared spectral study demonstrates CO binding to Cu(B).

The purpose of the work was to provide a crystallographic demonstration of the venerable idea that CO photolyzed from ferrous heme-a3 moves to the nearby cuprous ion in the cytochrome c oxidases. Crystal structures of CO-bound cytochrome ba3-oxidase from Thermus thermophilus, determined at ~ 2.8 – 3.2 A resolution, reveal a Fe-C distance of ~2.0 A, a Cu-O distance of 2.4 A and a Fe-C-O angle of ~126°. Upon photodissociation at 100 K, X-ray structures indicate loss of Fea3-CO and appearance of CuB-CO having a Cu-C distance of ~1.9 A and an O-Fe distance of ~2.3 A. Absolute FTIR spectra recorded from single crystals of reduced ba3–CO that had not been exposed to X-ray radiation, showed several peaks around 1975 cm−1; after photolysis at 100 K, the absolute FTIR spectra also showed a significant peak at 2050 cm−1. Analysis of the “light’ minus ‘dark’ difference spectra showed four very sharp CO stretching bands at 1970 cm−1, 1977 cm−1, 1981 cm−1, and 1985 cm−1, previously assigned to the Fea3-CO complex, and a significantly broader CO stretching band centered at ~2050 cm−1, previously assigned to the CO stretching frequency of CuB bound CO. As expected for light propagating along the tetragonal axis of the P43212 space group, the single crystal spectra exhibit negligible dichroism. Absolute FTIR spectrometry of a CO-laden ba3 crystal, exposed to an amount of X-ray radiation required to obtain structural data sets before FTIR characterization, showed a significant signal due to photogenerated CO2 at 2337 cm−1 and one from traces of CO at 2133 cm−1; while bands associated with CO bound to either Fea3 or to CuB in “light” minus “dark” FTIR difference spectra shifted and broadened in response to X-ray exposure. In spite of considerable radiation damage to the crystals, both X-ray analysis at 2.8 and 3.2 A and FTIR spectra support the long-held position that photolysis of Fea3-CO in cytochrome c oxidases leads to significant trapping of the CO on the CuB atom; Fea3 and CuB ligation, at the resolutions reported here, are otherwise unaltered.
Externalizing disorders: beyond psychosocial and biological correlates.

Over the past 25 years, a great deal of effort has been devoted to identifying causal risk factors or biological trait markers for externalizing disorders. Both have important implications for the care of youths with these troubling symptoms. However, much of the extant psychiatric research (with the exception of recent geneYenvironment studies) has focused on demonstrating that various psychosocial or biological characteristics are correlated with externalizing disorders. The next step in this field is to systematically investigate whether these correlates are valid risk factors or trait markers. 1Y3 Two studies reported in this month’s issue of the Journal exemplify transitional work between the first and second generations of risk factor and biological marker studies in externalizing disorders. In the first of these two studies, Ashford and colleagues 4 move beyond the frequently replicated association between maternal smoking in pregnancy and offspring externalizing disorders to investigate the psychopathological effects of maternal smoking with a more complex set of hypotheses. Animal data suggest that prenatal exposure to nicotine not only alters fetal development of the dopaminergic systems but also produces long-term effects on the innervation and synaptic activity of noradrenergic and serotonergic neurons. 5,6 Data such as these suggest that prenatal nicotine exposure could produce symptoms of both externalizing and internalizing disorders in offspring, but the few studies testing this hypothesis have reported contradictory findings. However, previous studies have not adequately accounted for age cohort effects on the prevalence of internalizing and externalizing disorders, frequent co-occurrence of the two types of disorders, or possible confounding effects of attention problems on both internalizing and externalizing disorders. To address these issues, the investigators in this study used growth curve modeling to analyze data on psychopathology in exposed and nonexposed boys and girls assessed three times from the ages of 5 to 8 years. Their models adjusted for effects of internalizing/externalizing comorbidity, attention problems, social difficulties, maternal mental health, and demographic characteristics. The results indicate that prenatal exposure to >10 cigarettes per day is a predictor of externalizing and internalizing disorders and that these effects are durable from early childhood through late adolescence. The study by Beauchaine et al. 7 demonstrates a new line of
An automata-theoretic approach to hardware/software co-verification

In this paper, we present an automata-theoretic approach to Hardware/ Software (HW/SW) co-verification. We designed a co-specification framework describing HW/SW systems; synthesized a hybrid Buchi Automaton Pushdown System model for co-verification, namely Buchi Pushdown System (BPDS), from the co-specification; and built a software tool for deciding reachability of BPDS models. Using our approach, we succeeded in co-verifying the Windows driver and the hardware model of the PIO-24 digital I/O card, finding a previously undiscovered software bug. In addition, our experiments have shown that our co-verification approach performs well in terms of time and memory usages.
Zyme, a novel and potentially amyloidogenic enzyme cDNA isolated from Alzheimer's disease brain.

The deposition of the β amyloid peptide in neuritic plaques and cerebral blood vessels is a hallmark of Alzheimer's disease (AD) pathology. The major component of the amyloid deposit is a 4.2-kDa polypeptide termed amyloid β-protein of 39–43 residues, which is derived from processing of a larger amyloid precursor protein (APP). It is hypothesized that a chymotrypsin-like enzyme is involved in the processing of APP. We have discovered a new serine protease from the AD brain by polymerase chain reaction amplification of DNA sequences representing active site homologous regions of chymotrypsin-like enzymes. A cDNA clone was identified as one out of one million that encodes Zyme, a serine protease. Messenger RNA encoding Zyme can be detected in some mammalian species but not in mice, rats, or hamster. Zyme is expressed predominantly in brain, kidney, and salivary gland. Zyme mRNA cannot be detected in fetal brain but is seen in adult brain. The Zyme gene maps to chromosome 19q13.3, a region which shows genetic linkage with late onset familial Alzheimer's disease. When Zyme cDNA is co-expressed with the APP cDNA in 293 (human embryonic kidney) cells, amyloidogenic fragments are detected using C-terminal antibody to APP. These co-transfected cells release an abundance of truncated amyloid β-protein peptide and shows a reduction of residues 17–42 of Aβ (P3) peptide. Zyme is immunolocalized to perivascular cells in monkey cortex and the AD brain. In addition, Zyme is localized to microglial cells in our AD brain sample. The amyloidogenic potential and localization in brain may indicate a role for this protease in amyloid precursor processing and AD.