cssi/SciSciGPT-SciSciNet huggingface dataset:
Dielectric relaxation in liquids and solids

RELAXATION is the lag in the response of a system to change in the forces to which it is subjected.1 It is thus a rather general phenomenon whose existence becomes apparent when its rate is not far from being of the same order of magnitude as that of the change of the applied forces. It may consist, for example, of lag in response to the following conditions: a change of temperature which affects the determination of thermal properties; a change of stress which affects mechanical stretching or viscous flow; or a change of electric field which tends to lower the dielectric constant. The relaxation rate is the rate at which a system comes into equilibrium with its surroundings when such a change occurs. When the relaxation rate is very different from that of the change of the constraining influence, the process involving the relaxation may not be noticed. For example, when a dielectric constant is measured at a frequency which is very low or very high in comparison with the dielectric relaxation rate, no loss of energy is observed.
Efficacy of an Escherichia coli J-5 mutant strain bacterin in the protection of calves from endotoxin disease caused by subcutaneous challenge with endotoxins from Escherichia coli

The purpose of this trial was to examine the potential of a new Escherichia (E) coli J-5 mutant strain bacterin to reduce the severity of clinical disease caused by subcutaneous challenge with endotoxins of Gram-negative bacteria in calves. Day-old to 3-day old calves (n = 40 per study phase) were randomly assigned to either of two treatment groups, i.e. a vaccinated or a placebo group. Calves in the vaccinated group received an inactivated bacterin containing a J-5 mutant strain of E. coli via subcutaneous route at 2-4 days of age and at 14 days thereafter. The placebo contained only adjuvant and saline in lieu of the antigen. Lipopolysaccharides (LPS) originating from E. coli were administered subcutaneously 3 weeks after the booster dose. The LPS challenge dosages were 1 and 8 microg/kg in study phases I and II, respectively. Various clinical, physiological, hematological, and serological parameters were measured at specific time intervals after challenge. The data were mostly analysed using peak changes from baseline recorded during the observation period. By the time of challenge the titers in vaccinated calves had increased significantly more than in the unvaccinated controls. Disease severity following subcutaneous challenge was dose dependent. In phase I, placebo calves were only mildly challenged whereas in phase II placebo calves showed a moderate challenge. After a mild challenge, there was little evidence of protection due to vaccination as only attitude was significantly improved in the vaccinates. In contrast, after a moderate challenge rectal temperature, hematocrit, blood glucose concentrations, and leukocyte changes were significantly better in the vaccinated group. In conclusion, the results of this study show that following a subcutaneous endotoxin challenge that induces a moderate clinical response, calves that were previously vaccinated with the E. coli J-5 bacterin were better protected than those in the placebo group.
A PARTIAL INTEGRATION FORMULA FOR PRODUCT INTEGRALS OF UNBOUNDED OPERATOR-VALUED FUNCTIONS

The partial integration formula for product integrals In (6, 7), Masani discusses the relationship between the " partial integration formula" for product integrals and the Trotter product formula, deriving the latter from the former for bounded operator-valued functions. He also asks whether an analogous relationship (from which Trotter's formula for unbounded operators would follow) can be established for unbounded operator-valued functions. In this note we address this question, providing conditions under which a partial integration formula for unbounded operators is valid, and exploring its implications for the Trotter product formula. We now describe our main results. Let X be a Banach space, and let e(X) denote the set of closed linear operators on X. Set
BEHAVIOUR OF THE MAGNETISATION AND TRANSPORT CURRENT IN NbZr WIRE

The behavior of the magnetization and transport current in Nb- Zr wire in transverse fields was investigated. The hard superconductor model of Beam provides a qualitative understanding of the magnetization. Possible explanations for some phenomena associated with Nb-- Zr solenoids are suggested by the data. Relations between the transport current, critical current, magnetization, field and current changes, etc., suggest the invalidity of pulsed field-pulsed current measurements of the critical current. (D.C.W.)
Quasiconvexification in W 1,1 and optimal jump microstructure in BV relaxation

An integral representation for the relaxation in $BV(\Omega;\rn{p})$ of the functional $$ u \mapsto \io W(\nabla u(x)) dx +\hn(S(u)) $$ with respect to BV weak * convergence is obtained. The bulk term in the integral representation reduces to the quasiconvexification of W, and we describe optimal behavior of approximating sequences along S(u), for scalar valued u.
14.7 A 300GHz frequency synthesizer with 7.9% locking range in 90nm SiGe BiCMOS

The THz/sub-mm-Wave band is known to provide unique applications in spectroscopy, imaging and high-data-rate wireless communication. An accurate THz source is essential in coherent communications, radar systems, and frequency metrology. Recently, THz sources based on coupled VCOs with harmonic generation have been proposed [1]. However, open-loop signal sources exhibit severe frequency fluctuation, and are vulnerable to temperature/process/supply-induced frequency drift. The need for precise oscillation frequency with wide tuning range and low close-in phase noise calls for closed-loop topologies. Millimeter-Wave PLLs incorporating push-push VCOs have been demonstrated up to 164GHz [2] in silicon technology. [3] presented a 300GHz PLL with 0.12% locking range in III-IV technology.
Grifonin-1: A Small HIV-1 Entry Inhibitor Derived from the Algal Lectin, Griffithsin

Background: Griffithsin, a 121-residue protein isolated from a red algal Griffithsia sp., binds high mannose N-linked glycans of virus surface glycoproteins with extremely high affinity, a property that allows it to prevent the entry of primary isolates and laboratory strains of T- and M-tropic HIV-1. We used the sequence of a portion of griffithsin's sequence as a design template to create smaller peptides with antiviral and carbohydrate-binding properties. Methodology/Results: The new peptides derived from a trio of homologous β-sheet repeats that comprise the motifs responsible for its biological activity. Our most active antiviral peptide, grifonin-1 (GRFN-1), had an EC50 of 190.8±11.0 nM in in vitro TZM-bl assays and an EC50 of 546.6±66.1 nM in p24gag antigen release assays. GRFN-1 showed considerable structural plasticity, assuming different conformations in solvents that differed in polarity and hydrophobicity. Higher concentrations of GRFN-1 formed oligomers, based on intermolecular β-sheet interactions. Like its parent protein, GRFN-1 bound viral glycoproteins gp41 and gp120 via the N-linked glycans on their surface. Conclusion: Its substantial antiviral activity and low toxicity in vitro suggest that GRFN-1 and/or its derivatives may have therapeutic potential as topical and/or systemic agents directed against HIV-1.
Interdisciplinary Medical Social Work: A Working Taxonomy

Findings from a year-long exploratory study aimed at describing universal functions of medical social work with interdisciplinary teams in acute care settings are reported here. A universal taxonomy of interdisciplinary social work skills and competencies was empirically identified through a participatory action research framework. Findings support previous conceptual descriptions of medical social work's overarching and historical role to help interdisciplinary teams in acute care to consider patients' home environment, knowledge, beliefs, culture, and resources during assessment, treatment, and discharge planning. The empirically determined taxonomy reported is intended to provide social workers a framework with which to articulate and evaluate their core competencies on interdisciplinary medical teams.
Amino-terminal and carboxyl-terminal residues of rabbit muscle M 4 lactate dehydrogenase: comparison with other vertebrate species.

Abstract 1. 1. Amino-terminal analysis of rabbit muscle M 4 lactate dehydrogenase demonstrated the absence of a free amino acid at the amino-terminus of the protein. 2. 2. Quantitative determination of bound acetyl groups gave a value of 3.1–3.3 moles/mole of protein (mol. wt. of 140,000). 3. 3. The amino-terminal peptide, characterized as N -acetylalanylalanine, was isolated from pronase digests of the protein, and quantitative recovery experiments indicate that all acetyl residues present in commercial preparations are found at the amino-termini. 4. 4. Phenylalanine was shown to be the carboxyl-terminal residue in the M 4 isozyme, while both leucine and phenylalanine were found at the carboxyl-terminus in a mixture of the M 4 , M 3 H, M 2 H 2 isozymes.
Conjunctive Management of Water Resources in the Context of Texas Water Law

: This paper examines the critical interaction between existing Texas water law and the state's water resources. Conjunctive use and management of interrelated water resources, though seldom practiced, is generally considered desirable. However, a significant barrier to the coordinated, efficient use and management of water resources is the legal division of water in the various phases of the hydrologic cycle into different classes and recognition of well-defined water rights in the separate phases. Several examples of the problems which relate to, or result from, present Texas water law and which prevent correlated water resource management are discussed. Any substantive revision of Texas law, particularly ground water law, will apparently be difficult to achieve in the immediate future, primarily because of the large number of recognized private water rights and the political power inherent in them. Data necessary for operation of conjunctive management systems are gradually being acquired, and perhaps someday other hydrologic phases can be integrated with surface and ground water. Nevertheless, Texas courts and the legislature have sufficient information on the interrelated hydrologic cycle so that prospective water conflicts should be anticipated and avoided. Great care must be exercised in the recognition of new types of private water rights or extension of existing rights, because this institutional structure, once established, presents a formidable obstacle to desirable revisions of the law.
Protein CorreLogo: an X3D representation of co-evolving pairs, tertiary structure, ligand binding pockets and protein-protein interactions in protein families

To understand the functional elements of a protein structure biologists use domain specific 3D viewers (PDB) that are written to process the coordinates of atoms that represent the solved protein structure using X-Ray crystallography or NMR. The PDB viewers have been written to capture specific or common features of interest to the researcher. With the explosion of protein sequence data comparative studies and statistical analysis of data can indicate regions of interest in 3D models. The ability to integrate statistical data into existing PDB viewers is difficult because the software is typically written to accomplish very specific functional goals and does not support exporting to a standard 3D format. In this paper, the PDB data is shown as X3D PDB ribbon models that are augmented with statistically significant data and compared to an Information-Rich Virtual Environment represented as a Protein CorreLogo X3D model.A protein family (Pfam) represents multiple alignments of protein sequences where protein domains and the tertiary structures have evolutionary conserved regions representing protein function. Various information properties of the protein family, the tertiary structure from a sequence's PDB structure and ligand binding pockets are combined to create a 3D Protein CorreLogo model. The multiple sequence alignment from the protein family is used to detect co-evolving amino acid pairs using mutual information. Co-evolving pairs are indicated as a column with color coding to represent the physio-chemical properties of each co-evolving amino acid combination. Additional visualizations along each axis include the 2D sequence logo, the degree of insert regions in the protein family and the surface accessibility of each amino acid for the referenced PDB sequence. The Protein CorreLogo model is based on X3D (VRML) facilitating immersive viewing of complex data relationships and detected co-evolving pairs.Two protein families are presented in the results section that compare the Protein CorreLogo model with a representative X3D RDB ribbon model showing the structural significance of predicted co-evolving amino acid pairs using mutual information. One example protein family, with proteins that bind cyclic nucleotides (PF00027.18), is given where the co-evolving pairs are potential markers for ligand binding pocket regions. Another example protein family, with SH3 domains that are involved in signal transduction related to cytoskeletal organization (PF00018.16), shows significant mutual information occurring between two pairs of amino acids that are in contact in the intertwined dimer structure but are on opposite ends of the tertiary structure.Protein CorreLogo X3D models and X3D PDB ribbon models can be found at http://www.proteinx3d.com
A Review of The Empirical Ethical Decision-Making Literature: 1996–2003

This review summarizes and critiques the empirical ethical decision-making literature from 1996–2003. One hundred and seventy-four articles were published in top business journals during this period. Tables are included that summarize the findings by dependent variable – awareness, judgment, intent, and behavior. We compare this review with past reviews in order to draw conclusions regarding trends in the ethical decision-making literature and to surface directions for future research.
Addition of metolazone to overcome tolerance to furosemide in infants with bronchopulmonary dysplasia

A decreased response to the loop diuretic furosemide develops within a few doses in young infants. We tested the hypothesis that the use of the thiazide-like diuretic metolazone, in combination with furosemide, would inhibit water and electrolyte reabsorption and overcome pharmacologic tolerance to furosemide alone. Infants with bronchopulmonary dysplasia of similar gestational and postnatal ages were randomly assigned to one of three groups. Group 1 (n=6) received furosemide (1 mg/kg per dose) intravenously every 24 hours for a total of five doses. Group 2 (n=8) received the same treatment as group 1, but in addition metolazone (0.2 mg/kg per dose) was given enterally with doses 3 and 4 of furosemide. Group 3 (n=8) received metolazone (0.2 mg/kg per dose) enterally every 24 hours for five doses. Urine was collected before the first diuretic dose and throughout the study for determination of the urine flow rate; urinary excretion of sodium, chloride, and potassium; and creatinine clearance. Urinary flow rate and urinary sodium and chloride excretion increased after the first dose in all groups. In the infants treated with either furosemide or metolazone, urinary flow rate and urinary and chloride excretion returned to baseline values after the last three doses. In contrast, when furosemide was administered with metolazone, urinary flow rate and urinary excretion of sodium, chloride, and potassium were greater than the values for baseline and for the previous dose, as well as for the corresponding doses of furosemide in group 1 and metolazone in group 3. Tolerance to furosemide (group 1) and metolazone (group 3) appeared to be explained by compensatory increased sodium and chloride reabsorption without changes in creatinine clearance. We conclude that the administration of metolazone with furosemide enhances diuresis, natriuresis, and chloruresis and overcomes the rapid development of tolerance to furosemide in infants with bronchopulmonary dysplasia by blocking the compensatory increase in renal sodium and chloride absorption.
The one world school house: education reimagined

In Salman Khan’s new book, The One World School House: Education Reimagined, Khan leverages his popular status as the “world’s teacher” (Webley, 2012) to provide his own critique of the US educatio...
Improving Outcome of Psychosocial Treatments by Enhancing Memory and Learning

Mental disorders are prevalent and can lead to significant impairment. Some progress has been made toward establishing treatments; however, effect sizes are small to moderate, gains may not persist, and many patients derive no benefit. Our goal is to highlight the potential for empirically supported psychosocial treatments to be improved by incorporating insights from cognitive psychology and research on education. Our central question is: If it were possible to improve memory for the content of sessions of psychosocial treatments, would outcome substantially improve? We leverage insights from scientific knowledge on learning and memory to derive strategies for transdiagnostic and transtreatment cognitive support interventions. These strategies can be applied within and between sessions and to interventions delivered via computer, the Internet, and text message. Additional novel pathways to improving memory include improving sleep, engaging in exercise, and using imagery. Given that memory processes change across the lifespan, services to children and older adults may benefit from different types and amounts of cognitive support.
Variation of within-day foraging costs in the striped mouse (Rhabdomys pumilio)

Abstract Foraging behavior is influenced by spatial and temporal habitat heterogeniety. Here we report on within-day foraging and perceived risk of predation by the striped mouse (Rhabdomys pumilio) in a grassland savannah with wooded “islands” using giving-up densities (GUD, amount of food left behind in depletable food patches). Higher GUDs correspond to higher forging costs. GUDs were measured six times per day at 2-h intervals from paired stations along fern–grass habitat boundaries at 3 and 6 m distances from 10 wooded islands. R. pumilio's GUDs varied significantly over the course of the day with highest GUDs during the afternoon hours of 1–3 pm, and lowest between 7 and 9 am in the morning. The same pattern was consistent for both habitats (fern and grass) and distances from the wooded islands. GUDs decreased with distance from the woody islands in both fern and grass habitats and were significantly lower in the fern habitat. This activity pattern suggests that R. pumilio responds to a spectrum of spatially and temporally varying risks from a variety of predators including aerial predators that increase risk as they make use of mid-day thermals.
Active control of sound power using acoustic basis functions as surface velocity filters

An improved method of active structural acoustics control is presented that is based on the minimization of the total power radiated from any structure expressed in terms of a truncated series sum. Each term of this sum is related to the coupling between the orthogonal eigenvectors of the radiation impedance matrix (referred to as ‘‘basis functions’’ in this paper) and the structural surface velocity vector. The basis functions act as surface velocity filters. These acoustic basis functions are found to be weak functions of frequency but their corresponding weighting coefficients increase monotonically with frequency. The minimization of the radiated power is shown to result in a structural surface velocity vector that couples poorly to those acoustic basis functions that account for high‐efficiency sound radiation. This strategy is demonstrated numerically for a clamped–clamped baffled beam in air. Point force primary and control actuators (shakers) are used to explore the control mechanisms. As expected...
Magneto-Impedance Biosensor With Enhanced Sensitivity for Highly Sensitive Detection of Nanomag-D Beads

A magnetoimpedance (MI) biosensor based on Co-based amorphous ribbon was designed and tested to detect functionalized Nanomag-D magnetic beads. While previous studies were focused mainly on exploring the MI change for biosensing, we show that the sensitivity of the biosensor can be enhanced when the change in ac magnetoresistance (MR) or magnetoreactance (MX) is used. The frequency at which the sensitivity of the sensor is optimized can be tuned. This is of potential interest in developing functional biosensors with improved sensitivity and tunable frequency.
Identification and characterization of a HeLa nuclear protein that specifically binds to the trans-activation-response (TAR) element of human immunodeficiency virus

Abstract Human immunodeficiency virus type 1 RNAs contain a sequence, trans-activation-response (TAR) element, which is required for tat protein-mediated trans-activation of viral gene expression. We have identified a nuclear protein from extracts of HeLa cells that binds to the TAR element RNA in a sequence-specific manner. The binding of this 68-kDa polypeptide was detected by UV cross-linking proteins to TAR element RNA transcribed in vitro. Competition experiments were performed by using a partially purified preparation of the protein to quantify the relative binding affinities of TAR element RNA mutants. The binding affinity of the TAR mutants paralleled the reported ability of those mutants to support tat trans-activation in vivo. We propose that this cellular protein moderates TAR activity in vivo.
Notes on an important botanical trip (1799–1800) of J. P. Rottler on the Coromandel Coast (India) with a translation of his original text, explanatory notes and a map

Abstract Matthew, K. M., 1993. Notes on an important botanical trip (1799-1800) of J. P. Rottler on the Coromandel Coast (India) with a translation of his original text, explanatory notes and a map. J. P. Rottler (1749-1836) made extensive collections on the Coromandel Coast in south India. The paper presented here in translation was one of Rottler's major publications, which, along with four indexes and a map, now newly prepared, should prove useful for a new study of Rottler's contributions.
Dendritic cells in melanoma immunotherapy

No consensus exists regarding optimal systemic treatment for melanoma in the adjuvant or metastatic disease setting. Dendritic cell vaccine therapy, though investigational at present, offers very promising preliminary data that warrant exploration, and patients with existing disease and those seeking adjuvant treatment should evaluate open protocols using this strategy.
Comparison of membrane-associated proteins of murine cytolytic and helper cloned T-cell lines: identification of a protein, p24, prominent in membrane fractions from cytolytic but not helper T-cells.

Abstract It has recently been reported that liposomes containing membrane components from cytolytic T-cell (T c ) clones could transfer lytic activity to noncytolytic T- and B-cell lines, strongly suggesting that T c possess membrane-associated molecules which noncytolytic lymphocytes lack and which play a critical role in the lytic mechanism. It was thus of interest to compare the membrane-associated proteins from T c -lines to those of noncytolytic helper T-cell (T H ) lines to determine whether any membrane-associated proteins unique to T c could be identified. Cells from three T c -lines and four T H -lines were internally labelled with [ 35 S]methionine and then disrupted by hypotonie lysis. Low-density (plasma membrane enriched) and high-density (endoplasmic reticulum enriched) membrane fractions were isolated from each cloned cell line and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions. Two proteins were identified which were prominent in the membrane fractions from each of the three T c -lines but not in the membrane fractions from any of the four T H -lines. One of these, p215, migrated as a broad band with an apparent mol. wt of 215,000. The other, p24, migrated as a sharp band, or tightly spaced doublet, with an apparent mol. wt of 24,000. Immunoprecipitation studies using monoclonal antibodies to T200, LFA-1, Thy 1 and Lyt 2 suggested that p215 was a variant of T200 found on T c -lines but not on T H -lines. Treatment of solubilized membrane proteins from T H -lines with anti-T200 precipitated a 185-kD protein seen on each of the T H -lines but on none of the T c -lines. In contrast, p24 was not precipitated by any of these monoclonal antibodies. It therefore appears that p24 represents a previously unidentified protein which is strongly expressed by T c but not by T H and is thus deserving of further study as to its functional significance.
Development of a unique laboratory scale fluidized bed wear testing unit

Abstract Significant wastage of internal bed components in fluidized bed combustors has been widely experienced throughout the industry. A major probable contribution to heat exchanger tube wastage in bubbling fluidized beds is mechanical in nature. It arises from the impact of blocks of defluidized particles thrown against tube undersides during either the passage of rising bubbles or the collapse of ‘teardrop’ like voids that form periodically under tubes. In an effort to investigate this process, isolated from other erosive or corrosive effects, a novel wear testing rig has been designed and built. This device simulates the particle block impact environment by the fast movement of a specimen rod vertically within a minimally fluidized bed. Data from initial room temperature tests indicate that rods exposed in the rig suffered losses which were similar in both magnitude and circumferential distribution to those experienced by tubes in other cold model studies that utilized more conventional fluidized bed units. The worn surface regions of the tested metallic rods were composed of a relatively hard multilayered composite of bed material and base metal that resulted from deposition of fine particle fragments and considerable surface deformation. Removal of material from this composite probably occurred primarily through a process of three-body microabrasion. For pure aluminum, a secondary process of layer spallation was active at circumferential locations where an exceptionally thick composite layer developed.
EFFECT OF TEMPERATURE AND PACKAGING FILM ON NUTRITIONAL QUALITY OF FRESH‐CUT SWEET POTATOES

Fresh-cut sweet potato slices were packaged in low (PD900), medium (PD961) and high permeability (PD941) film bags and stored at 2 or 8C for 14 days. Weight loss of slices stored at 8C was twofold greater than at 2C. Weight loss was significantly higher in slices packaged with PD941 film bags than other film bags. The type of packaging bag did not significantly affect the carbohydrate composition or nutritional content of the slices during storage. Dry matter and alcohol-insoluble solids (AIS) and mineral content decreased, but fructose, sucrose, total sugar and total carotenoid content increased during storage. The increases in sugars and decrease in AIS content were higher at 8C than at 2C. Glucose and crude protein content was not affected by storage temperature and duration and film bag type. PRACTICAL APPLICATIONS “The demand for fresh-cut sweet potato products is significantly increasing in the U.S., in both retail and foodservice markets. Consumers are placing increasing importance on the nutritional quality of food products in making their purchasing decisions. Therefore, the information pertaining to the composition of fresh-cut sweet potatoes is of commercial importance. This manuscript also provides practical information on the appropriate semi-permeable polymeric film bag and holding temperature for optimum fresh-cut sweet potato quality. The use of optimum modified atmosphere packaging material and maintenance of proper storage temperature is critical in influencing edible quality and nutritional composition of fresh-cut sweet potatoes. Commercial foodservice firms targeting fresh-cut sweet potatoes as a convenience food will potentially benefit from the information in this manuscript.”
A Search for H I in E+A Galaxies

We present the results of H I line and radio continuum observations of five nearby E+A galaxies. These galaxies have spectra that are dominated by a young stellar component but lack the emission lines characteristic of significant ongoing star formation. They are selected from a unique sample of 21 E+A's identified by Zabludoff et al. in their spectroscopic search (published in 1996) for E+A galaxies using the Las Campanas Redshift Survey, in which over 11,000 nearby galaxies were examined. The five E+A galaxies span a range of environments: three are in the field, and two are in clusters. Only one system was detected in H I emission, the field E+A galaxy EA 1, with a total flux of 0.30 ± 0.02 Jy km s-1 and an H I mass of 3.5 ± 0.2 × 109 h-2 M⊙. The H I morphology and kinematics of EA 1 suggest a galaxy-galaxy interaction, with a dynamical age of ~6 × 108 h-1 yr inferred from the H I tail lengths and velocities. This age estimate is consistent with the interpretation drawn from optical spectroscopy that starbursts in E+A galaxies began (and subsequently ended) within the last 109 yr. Our H I detection limits are such that if the other E+A's in our sample had the H I properties of EA 1, we would have detected (or marginally detected) them. We conclude that E+A galaxies have a range of H I properties. None of the galaxies were detected in radio continuum emission, with upper limits to the radio power of ~1021 h-2 W Hz-1. Our limits exclude the possibility that these E+A's are dust-enshrouded massive starburst galaxies, but they are insufficient to exclude modest star formation rates of less than a few h-2 M⊙ yr-1.
Some Aspects of Antarctic Geophysics

This paper is concerned mostly with the Antarctic Ice Sheet-first, the time required for the ice to build up to its present mass; second, its resent budget in terms of annual import and export; and third, its important role in the manufacture of cold air. DOI: 10.1111/j.2153-3490.1958.tb01986.x
DIPLOMACIA E POLÍTICA DOMÉSTICA: A LÓGICA DOS JOGOS DE DOIS NÍVEIS

A politica domestica e as relacoes internacionais com frequencia sao inextricavelmente vinculadas; todavia, as teorias existentes (particularmente as estatocentricas) nao levam adequadamente em consideracoes tais vinculos. Quando os lideres nacionais devem obter as ratificacoes (formais ou informais) dos membros de seus parlamentos para um acordo internacional, seus comportamentos em negociacoes refletem os imperativos simultâneos tanto de um jogo de politica domestica quanto de um jogo de politica internacional. Usando exemplos de cupulas economicas ocidentais, das negociacoes do Canal do Panama e do Tratado de Versalhes, dos programas de estabilizacao do Fundo Monetario Internacional, da Comunidade Europeia e de muitos outros contextos diplomaticos, o artigo oferece uma teoria da ratificacao. Ele enfatiza o papel das preferencias, coalizoes, instituicoes e praticas domesticas, das estrategias e taticas dos negociadores, da incerteza, das reverberacoes domesticas das pressoes externas e o papel dos interesses do negociador-chefe. Essa teoria de “jogos de dois niveis” tambem pode ser aplicavel a muitos outros fenomenos politicos, tais como a dependencia, os comites legislativos e as coalizoes multipartidarias.
Lazy Release Consistency for Hardware-Coherent Multiprocessors

Release consistency is a widely accepted memory model for distributed shared memory systems. Eager release consistency represents the state of the art in release consistent protocols for hardware-coherent multiprocessors, while lazy release consistency has been shown to provide better performance for software distributed shared memory (DSM). Several of the optimizations performed by lazy protocols have the potential to improve the performance of hardware-coherent multiprocessors as well, but their complexity has precluded a hardware implementation. With the advent of programmable protocol processors it may become possible to use them after all. We present and evaluate a lazy release-consistent protocol suitable for machines with dedicated protocol processors. This protocol admits multiple concurrent writers, sends write notices concurrently with computation, and delays invalidations until acquire operations. We also consider a lazier protocol that delays sending write notices until release operations. Our results indicate that the first protocol outperforms eager release consistency by as much as 20% across a variety of applications. The lazier protocol, on the other hand, is unable to recoup its high synchronization overhead. This represents a qualitative shift from the DSM world, where lazier protocols always yield performance improvements. Based on our results, we conclude that machines with flexible hardware support for coherence should use protocols based on lazy release consistency, but in a less ''aggressively lazy'' form than is appropriate for DSM.
Dispersion of optical and acoustical phonons in the zinc-blende group III-nitride superlattices

Abstract A comprehensive theoretical study of phonons in cubic GaN, AlN, Ga 1− x Al x N, and (GaN) m /(AlN) n superlattices (SLs) is reported using both simple and microscopic models. The new periodicity introduced by the SL structure causes zone folding of the acoustical modes allowing phonons with large q vectors, normally inactive in light scattering, to become Raman active. We predicted the frequencies of such modes in GaN/AlN SLs using elastic continuum, diatomic linear-chain, and rigid-ion models. In the rigid-ion model (RIM), the short range forces are optimized in terms of elastic constants and phonon energies at critical points while the long-range Coulomb forces are evaluated exactly via Ewald summation. The advantage of using RIM is that it permits the construction of a dynamical matrix entering into the secular equation for the SL vibrations of a given wavevector directly from the dynamical matrices of the bulk materials. For short period (GaN) m /(AlN) n SLs, the dependence of phonons on wavevectors both parallel and perpendicular to the growth direction [001] is investigated. Theoretical results for the GaN/AlN superlattices are compared and discussed with the GaAs/AlAs system as well as with the existing model calculation of Grille and Bechstedt. Unlike GaAs/AlAs, the larger optical phonon values and partially changed confinement characteristics in GaN/AlN superlattices are believed to have significant affects on the relaxation properties of electrons in group III-nitride material systems.
Enzymology of one-carbon metabolism in methanogenic pathways

Methanoarchaea, the largest and most phylogenetically diverse group in the Archaea domain, have evolved energy-yielding pathways marked by one-carbon biochemistry featuring novel cofactors and enzymes. All of the pathways have in common the two-electron reduction of methyl-coenzyme M to methane catalyzed by methyl-coenzyme M reductase but deviate in the source of the methyl group transferred to coenzyme M. Most of the methane produced in nature derives from acetate in a pathway where the activated substrate is cleaved by CO dehydrogenase/acetyl-CoA synthase and the methyl group is transferred to coenzyme M via methyltetrahydromethanopterin or methyltetrahydrosarcinapterin. Electrons for reductive demethylation of the methyl-coenzyme M originate from oxidation of the carbonyl group of acetate to carbon dioxide by the synthase. In the other major pathway, formate or H2 is oxidized to provide electrons for reduction of carbon dioxide to the methyl level and reduction of methyl-coenzyme to methane. Methane is also produced from the methyl groups of methanol and methylamines. In these pathways specialized methyltransferases transfer the methyl groups to coenzyme M. Electrons for reduction of the methyl-coenzyme M are supplied by oxidation of the methyl groups to carbon dioxide by a reversal of the carbon dioxide reduction pathway. Recent progress on the enzymology of one-carbon reactions in these pathways has raised the level of understanding with regard to the physiology and molecular biology of methanogenesis. These advances have also provided a foundation for future studies on the structure/function of these novel enzymes and exploitation of the recently completed sequences for the genomes from the methanoarchaea Methanobacterium thermoautotrophicum and Methanococcus jannaschii.
Modulation of abnormal defecation dynamics by biofeedback treatment in chronically constipated children with encopresis

To determine whether outcome in chronically constipated and encopretic children with abnormal defecation dynamics could be improved with biofeedback training, we randomly assigned patients, 5 to 16 years of age, to receive conventional treatment alone (n=19) or conventional plus biofeedback treatment (n=22) and evaluated physiologic outcome at 7 months and clinical outcome at 7 and 12 months. Eighty-six percent of patients learned normal defecation dynamics with up to six biofeedback sessions. At 7 months, 13% of conventionally treated and 77% of biofeedback-treated patients had normal defecation dynamics ( p p p p
Resistance to ascochyta blights of cool season food legumes

Ascochyta blights are the most important diseases of cool season food legumes (peas, lentils, chickpeas, and faba beans) and are found in nearly all production regions. Despite having the same common disease name, the pathogen species differ for each of the crops. These diseases cause serious yield losses under favourable cool and humid conditions. Planting resistant cultivars is often the first choice and most economical means in managing the diseases. Therefore breeding for resistance to ascochyta blights has been an important objective of many cool season food legume research programmes. Systematic screening of germplasm collections at international research centres and other national research programmes have identified useful resistance sources that have been used successfully to breed resistant or tolerant cultivars. Genetic studies have revealed inheritance patterns of the resistance genes. Genetic linkage analyses and QTL mapping have identified molecular markers that could be useful for marker-assisted selection and gene pyramiding. In general, research towards developing resistance to ascochyta blights in cool season food legume faces mainly two limitations: the lack of availability of efficient resistance sources and the lack of a good understanding of the variability of the pathogen populations. Research efforts to alleviate these limitations should be pursued. Given that modern technologies of marker development and genomics are available, further advances in deploying resistance to manage ascochyta blights in this group of legume crops will depend on concerted efforts in developing accurate screening procedures with adequate knowledge of pathogen variability and identification of additional sources of resistance.
Performance management in cognitive radio ad hoc networks using congestion based metric

In this paper, we examine performance management for cognitive radio (CR) ad hoc networks, and address the problem of data link congestion for secondary users. Our approach is to propose a metric based on the probability of contended link access and the probability of packet error to identify potential congestion on those links. We consider this metric in the context of a dynamic spectrum environment and account for effect of primary user activity on secondary user channel access. Specifically, since an ad hoc network is typically not controlled by a central base station, we propose using a clustered architecture that provides hierarchical network management utilizing a designated central manager and cluster heads that function as local managers. The cluster heads collect information from multiple layers of the protocol stack to capture the characteristics of CR ad hoc networks such as the location dependent spectrum availability. Then we define the average congestion level of the network and derive it analytically as a function of primary users' activities and CR users' strategy. The objective of the management action is to utilize a network level view of the congestion situation in the network by directing the CR nodes to select the highest quality links available and avoid congestion. Numerical results demonstrate the effectiveness of the proposed scheme.
Toxicity of systemic neonicotinoid insecticides to avocado thrips in nursery avocado trees

The efficacies of four systemic neonicotinoid insecticides applied to potted avocado trees at manufacturer-recommended rates were assessed against the avocado thrips, Scirtothrips perseae Nakahara. At the time of treatment, fully expanded first-flush young leaves were tagged for identification, and a proportion of these leaves was used in bioassays with second-instar thrips. At 7 weeks post-treatment, a second flush of leaves had fully expanded on the trees, and these leaves were included in additional bioassays comparing avocado thrips mortality on both first- and second-flush leaves. In bioassays with first-flush leaves, imidacloprid (273 mg AI pot−1) was the most effective insecticide, providing at least 70% mortality of thrips for 14 weeks. Thiamethoxam (137 mg AI pot−1), clothianidin (109 mg AI pot−1) and dinotefuran (241 mg AI pot−1) provided good control in bioassays that were conducted within 4 weeks of treatment, but thereafter their efficacies were inconsistent. In bioassays with second-flush leaves, imidacloprid provided at least 70% mortality up to 9 weeks after the insecticide application. Thereafter, mortality declined to 30% or lower. Bioassays with second-flush leaves collected from trees treated with thiamethoxam, clothianidin and dinotefuran resulted in unacceptably low thrips mortality. Monitoring of imidacloprid and thiamethoxam residues by ELISA showed that the greater persistence of imidacloprid in both first and second leaf flushes was due to a steadier uptake of this material. Although thiamethoxam residues rose quickly within the first leaf flush, levels had already begun to dissipate by the time the second leaf flush had started to develop. Copyright © 2007 Society of Chemical Industry
Quantum entanglement in photosynthetic light-harvesting complexes

Light harvesting components of photosynthetic organisms are complex, coupled, many-body quantum systems, in which electronic coherence has recently been shown to survive for relatively long time scales despite the decohering effects of their environments. Within this context, we analyze entanglement in multi-chromophoric light harvesting complexes, and establish methods for quantification of entanglement by presenting necessary and sufficient conditions for entanglement and by deriving a measure of global entanglement. These methods are then applied to the Fenna-Matthews-Olson (FMO) protein to extract the initial state and temperature dependencies of entanglement. We show that while FMO in natural conditions largely contains bipartite entanglement between dimerized chromophores, a small amount of long-range and multipartite entanglement exists even at physiological temperatures. This constitutes the first rigorous quantification of entanglement in a biological system. Finally, we discuss the practical utilization of entanglement in densely packed molecular aggregates such as light harvesting complexes.
Prey resources before spawning influence gonadal investment of female, but not male, white crappie

This research was funded by Federal Aid in Sport Fish Restoration Project F-69-P, administered jointly by United States Fish and Wildlife Service and Ohio Department of Natural Resources, Division of Wildlife, and the Department of Evolution, Ecology, and Organismal Biology at The Ohio State University.
Effects of C-terminal Truncations on Trafficking of the Yeast Plasma Membrane H+-ATPase

Within the large family of P-type cation-transporting ATPases, members differ in the number of C-terminal transmembrane helices, ranging from two in Cu2+-ATPases to six in H+-, Na+,K+-, Mg2+-, and Ca2+-ATPases. In this study, yeast Pma1 H+-ATPase has served as a model to examine the role of the C-terminal membrane domain in ATPase stability and targeting to the plasma membrane. Successive truncations were constructed from the middle of the major cytoplasmic loop to the middle of the extended cytoplasmic tail, adding back the C-terminal membrane-spanning helices one at a time. When the resulting constructs were expressed transiently in yeast, there was a steady increase in half-life from 70 min in Pma1Δ452 to 348 min in Pma1Δ901, but even the longest construct was considerably less stable than wild-type ATPase (t½ = 11 h). Confocal immunofluorescence microscopy showed that 11 of 12 constructs were arrested in the endoplasmic reticulum and degraded in the proteasome. The only truncated ATPase that escaped the ER, Pma1Δ901, traveled slowly to the plasma membrane, where it hydrolyzed ATP and supported growth. Limited trypsinolysis showed Pma1Δ901 to be misfolded, however, resulting in premature delivery to the vacuole for degradation. As model substrates, this series of truncations affirms the importance of the entire C-terminal domain to yeast H+-ATPase biogenesis and defines a sequence element of 20 amino acids in the carboxyl tail that is critical to ER escape and trafficking to the plasma membrane.
The biosynthetic gene cluster for the antitumor drug bleomycin from Streptomyces verticillus ATCC15003 supporting functional interactions between nonribosomal peptide synthetases and a polyketide synthase

Background: The structural and catalytic similarities between modular nonribosomal peptide synthetases (NRPSs) and polyketide synthases (PKSs) inspired us to search for a hybrid NRPS^PKS system. The antitumor drug bleomycin (BLM) is a natural hybrid peptide^polyketide metabolite, the biosynthesis of which provides an excellent opportunity to investigate intermodular communication between NRPS and PKS modules. Here, we report the cloning, sequencing, and characterization of the BLM biosynthetic gene cluster from Streptomyces verticillus ATCC15003. Results: A set of 30 genes clustered with the previously characterized blmAB resistance genes were de¢ned by sequencing a 85-kb contiguous region of DNA from S. verticillus ATCC15003. The sequenced gene cluster consists of 10 NRPS genes encoding nine NRPS modules, a PKS gene encoding one PKS module, ¢ve sugar biosynthesis genes, as well as genes encoding other biosynthesis, resistance, and regulatory proteins. The substrate speci¢cities of individual NRPS and PKS modules were predicted based on sequence analysis, and the amino acid speci¢cities of two NRPS modules were con¢rmed biochemically in vitro. The involvement of the cloned genes in BLM biosynthesis was demonstrated by bioconversion of the BLM aglycones into BLMs in Streptomyces lividans expressing a part of the gene cluster. Conclusion: The blm gene cluster is characterized by a hybrid NRPS^PKS system, supporting the wisdom of combining individual NRPS and PKS modules for combinatorial biosynthesis. The availability of the blm gene cluster has set the stage for engineering novel BLM analogs by genetic manipulation of genes governing BLM biosynthesis and for investigating the molecular basis for intermodular communication between NRPS and PKS in the biosynthesis of hybrid peptide^polyketide metabolites.