cssi/SciSciGPT-SciSciNet huggingface dataset:
AGCVIII kinases: at the crossroads of cellular signaling.

AGCVIII kinases regulate diverse developmental and cellular processes in plants. As putative mediators of secondary messengers, AGCVIII kinases potentially integrate developmental and environmental cues into specific cellular responses through substrate phosphorylation. Here we discuss the functionality and regulation of AGCVIII kinases. Specifically, we question the view that activities of AGCVIII kinases, like their animal counterparts, are regulated by a common regulator, 3-phosphoinositide-dependent protein kinase-1 (PDK1). Instead, increasing evidence suggests that Ca 2+ and phospholipids regulate AGCVIII kinases, by altering their activities or by affecting their subcellular localization. As AGCVIII kinases are at the crossroads of plant cellular signaling, they and the signaling networks in which they participate are keys to a better understanding of plant development and of interactions with their environment.
Large-scale selective sweep among Segregation Distorter chromosomes in African populations of Drosophila melanogaster.

Segregation Distorter (SD) is a selfish, coadapted gene complex on chromosome 2 of Drosophila melanogaster that strongly distorts Mendelian transmission; heterozygous SD/SD+ males sire almost exclusively SD-bearing progeny. Fifty years of genetic, molecular, and theory work have made SD one of the best-characterized meiotic drive systems, but surprisingly the details of its evolutionary origins and population dynamics remain unclear. Earlier analyses suggested that the SD system arose recently in the Mediterranean basin and then spread to a low, stable equilibrium frequency (1–5%) in most natural populations worldwide. In this report, we show, first, that SD chromosomes occur in populations in sub-Saharan Africa, the ancestral range of D. melanogaster, at a similarly low frequency (∼2%), providing evidence for the robustness of its equilibrium frequency but raising doubts about the Mediterranean-origins hypothesis. Second, our genetic analyses reveal two kinds of SD chromosomes in Africa: inversion-free SD chromosomes with little or no transmission advantage; and an African-endemic inversion-bearing SD chromosome, SD-Mal, with a perfect transmission advantage. Third, our population genetic analyses show that SD-Mal chromosomes swept across the African continent very recently, causing linkage disequilibrium and an absence of variability over 39% of the length of the second chromosome. Thus, despite a seemingly stable equilibrium frequency, SD chromosomes continue to evolve, to compete with one another, or evade suppressors in the genome.
Causal independence in algebraic quantum field theory

Ekstein has shown that causal independence neither implies nor is implied by commutativity in an infinite-dimensional, reducible construction. DeFacio and Taylor have presented a finite-dimensional irreducible example of Ekstein's proposition. Avishai and Ekstein have shown that the original question regarding locality for algebraic quantum field theories remainsopen. We concur with that claim and offer additional arguments. A new denumerably infinite-dimensional, irreducible example is presented here which shows that a sort of “orthogonality” among operators is involved. Some observations on localC*-andW*-algebras are given.
Choosing Weapons for the War on "Crack": An Operant Analysis

Addiction to "crack" cocaine has rapidly emerged as a crucial social and political problem, particularly in major urban areas. Working as they do in child and family services, health and mental health, and other major social institutional settings, as well as in clinical and policy positions dealing directly with crack users, social workers deal increasingly with the resulting casualties. The current knowledge base is limited, but sufficient information about this substance, and addictive behavior in general, currently exists to provide tentative directions for clinical practice, pilot projects in prevention and treatment, and community-level intervention. This article considers the existing information, examining the data from an operant perspective that focuses particularly on potentially manipulable environmental factors, congruent with the ecosystemic perspective that uniquely characterizes social work practice. Probable crucial contingencies are identified, and directions for future work are suggested.
Discovery of Manner Relations and Their Applicability to Question Answering

The discovery of semantic relations from text becomes increasingly important for applications such as Question Answering, Information Extraction, Summarization, Text Understanding and others. This paper presents a method for the automatic discovery of manner relations using a Naive Bayes learning algorithm. The method was tested on the UPenn Treebank2 corpus, and the targeted manner relations were detected with a precision of 64.44% and a recall of 68.67%.
A statistical evaluation of microtensile bond strength methodology for dental adhesives.

Abstract Objectives The purpose of this study was to determine the correlation between beams from the same tooth in a microtensile bond strength study and to examine their effect on the interpretation of results. Methods A flat occlusal dentin surface was exposed using wet 180, 240, and 320-grit SiC paper on caries-free human molar teeth. Adhesive was applied followed by 6 mm of composite (CoreRestore2) applied in 2 mm increments. Four adhesives were used: Optibond FL, light-cure, dual-cure, and self-cure Optibond Solo Plus. Nine beams (1 mm2) were obtained from fifteen teeth for each group, labeled to indicate the orientation of the beams to each other and stored in artificial saliva at 37 °C for 1 week or 3 months. Microtensile dentin bond strengths were determined using a non-trimming technique. Statistical comparisons between adhesive-storage combinations were performed using ANOVA. Analyses were performed assuming statistical independence between all beams and then repeated using a random tooth effect to account for correlations between beams from the same tooth. Results Significant correlations were found between beams. No pattern was observed in the correlations related to the orientations of the beams to each other. Conclusions regarding statistical significance of comparisons (at alpha = 0.05) were sometimes affected by the incorrect assumption of independent beams. The degree of correlation was large enough to severely affect power and sample size calculations. Significance Analyses of microtensile dentin bond strength studies need to account for correlations between beams to avoid over-stating statistical significance of study results.
A hybrid nudging-ensemble Kalman filter approach to data assimilation. Part II: application in a shallow-water model

A hybrid nudging-ensemble Kalman filter (HNEnKF) data assimilation approach, explored in the Lorenz three-variable system in Part I, is tested in a two-dimensional shallow-water model for dynamic analysis and numerical weather prediction. The HNEnKF effectively combines the advantages of the ensemble Kalman filter (EnKF) and the observation nudging to achieve more gradual and continuous data assimilation by computing the nudging coefficients from the flow-dependent, time-varying error covariances of the EnKF. It can also transform the gain matrix of the EnKF into additional terms in the model’s predictive equations to assist the data assimilation process. The HNEnKF is tested for both a wave case and a vortex case with different observation frequencies and observation networks. The HNEnKF generally produces smaller root mean square (RMS) errors than either nudging or EnKF alone. It also has better temporal smoothness than the EnKF and lagged ensemble Kalman smoother (EnKS). The HNEnKF allows the gain matrix of the EnKF to be applied gradually in time, reducing the error spikes commonly found around the analysis times when using intermittent data assimilation methods. Therefore, the HNEnKF produces a seamless analysis with better inter-variable consistency and dynamic balance than the intermittent EnKF. Keywords: ensemble Kalman filter (EnKF); nudging; hybrid data assimilation; dynamic balance; insertion noise; shallow-water model (Published: 29 May 2012) Citation: Tellus A 2012, 64 , 18485, http://dx.doi.org/10.3402/tellusa.v64i0.18485
Decision processes in frequency discrimination.

Frequency discrimination performance was measured in 2IFC, same‐different, and yes‐no paradigms using two methods common in the literature, pure‐tone discrimination and FM detection. For the pure‐tone method, performance in 2IFC exceeded performance in yes‐no by more than the factor of √ predicted by the traditional TSD decision theory analysis. For the FM method, performance in 2IFC exceeded performance in yes‐no by less than a factor of √. The subjects were then asked to distinguish between two different modulation ranges. The ratio of performance in 2IFC to performance in yes‐no was greater in this FM‐discrimination task than in the earlier FM‐detection task. These results are consistent with other studies comparing performance in different paradigms for detection of tones in noise and intensity discrimination. [Supported by grants from NIH and NSF.]
Influence on Motor Performance of Simultaneous Delayed and Synchronous Pure-Tone Auditory Feedback

A study was made of the effect of the presentation order of delay/synchronous (DAF/SAF) intensity ratios on tapping performance under simultaneously presented synchronous and delayed auditory feedb...
Surface texturing for adaptive solid lubrication

Abstract The production of surface micro-patterns in steel substrates for solid lubricant (SL) reservoirs was previously shown to provide improved wear and frictional properties in sliding contact. We report on the fabrication of micrometer-sized dimple patterns of different sizes on TiAlCN hard coatings produced by cathodic arc vacuum evaporation. These dimples were produced by reactive ion etching in a mixed Ar/CF 4 plasma. An overlayer of MoS 2 or Mo/MoS 2 /Ag SLs was deposited on the micro-textured surfaces using unbalanced magnetron sputtering. The tribological properties of the coatings were investigated against Si 3 N 4 in dry sliding at 25 °C and in air at 570 °C. The coatings and respective wear tracks were examined using scanning electron microscopy (SEM), optical microscopy (OM), optical profilometry (OP), energy dispersive x-ray spectroscopy (EDX), and micro-Raman spectroscopy. The frictional and wear properties of textured and flat surfaces were compared. A significant decrease in friction and wear coefficients was achieved at 25 °C and 570 °C for the textured films because the dimples acted as reservoirs that provided a new supply of SLs to the contact surfaces. The chemistry and phase analysis of the coating wear tracks showed temperature adaptive behavior with the lubrication being provided primarily by MoS 2 at 25 °C and by silver and silver molybdate compounds at high temperature.
Microfluidic integration of nanomechanical resonators for protein analysis in serum

Abstract We describe a technique for reversibly encapsulating nanomechanical resonant sensors within microfluidic channels that are reusable and easy to fabricate. We demonstrate the feasibility and sensitivity of our microfluidic system by detecting prostate specific antigen (PSA) at 1–100 fM concentrations in serum, using a nanoparticle-based mass-labeling sandwich assay. By comparing these results to our previous data for PSA detection, we observe enhanced assay sensitivity in a significantly reduced time with the microfluidic assay. In addition, we show that a binary mixture of the proteins vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8) can be detected in serum using a single microfluidic channel. This work lays the groundwork for future applications of these nanomechanical resonant devices for highly sensitive, multiplexed protein analysis using microfluidics.
Mutants of vesicular stomatitis virus blocked at different stages in maturation of the viral glycoprotein

Abstract Maturation of the vesicular stomatitis virus (VSV) glycoprotein (G) to the cell surface is blocked at the nonpermissive temperature in cells infected with temperature-sensitive mutants in the structural gene encoding for G. We show here that these mutants fall into two discrete classes with respect to the stage of post-translational processing at which the block occurs. In all cases the mutant glycoproteins are inserted normally into the endoplasmic reticulum membrane, receive the two high-mannose oligosaccharides, and apparently lose the NH 2 -terminal signal sequence of 16 amino acids. In cells infected with one class of mutants, no further processing of the glycoprotein occurs, and we conclude that the mutant protein is blocked at a pre-Golgi stage. In cells infected with ts L511(V), however, addition of the terminal sugars galactose and sialic acid occurs normally. Thus the maturation of G proceeds through several Golgi functions but is blocked before its appearance on the cell surface. The oligosaccharide chain of ts L511(V) G, accumulated at either the permissive (where surface maturation occurs) or the nonpermissive temperature, lacks one saccharide residue, probably fucose. In addition, no fatty acid residues are added to the ts L511(V) G protein at the nonpermissive temperature, although addition does occur under permissive conditions.
HSF1 Protects Neurons through a Novel Trimerization- and HSP-Independent Mechanism

Heat shock factor 1 (HSF1) protects neurons from death caused by the accumulation of misfolded proteins. It is believed that this protective effect is mediated by the transcriptional stimulation of genes encoding heat shock proteins (HSPs), a family of chaperones that refold or degrade misfolded proteins. Whether HSF1 is protective when neuronal death is not caused by protein misfolding has not been studied. Here, we report that HSF1 expression is necessary for the survival of rat neurons and that HSF1 mRNA and protein expression is reduced in neurons primed to die. Knock-down of HSF1 induces death of otherwise healthy neurons, whereas reestablishment of elevated levels of HSF1 protects neurons even when death is not due to accumulation of misfolded proteins. Neuroprotection by HSF1 does not require its trimerization, an event obligatory for the binding of HSF1 to heat shock elements within HSP gene promoters. Moreover, knock-down of HSP70 or blockade of HSP90 signaling does not reduce neuroprotection by HSF1. Although several neuroprotective molecules and signaling pathways, including CaMK, PKA, Casein kinase-II, and the Raf-MEK-ERK and PI-3K-Akt pathways, are not required for HSF1-mediated neuroprotection, protection is abrogated by inhibition of classical histone deacetylases (HDACs). We report that the novel mechanism of neuroprotection by HSF1 involves cooperation with SIRT1, an HDAC with well documented neuroprotective effects. Using a cell culture model of Huntington's disease, we show that HSF1 trimerization is not required for protection against mutant huntingtin-induced neurotoxicity, suggesting that HSF1 can protect neurons against both proteinopathic and nonproteinopathic death through a noncanonical pathway.
A Polarographic Study of Some Veratrum Viride Alkaloids

The results of a study of the polarographic behavior of jervine, veratramine, and veratrosine dissolved in a mixture of alcohol and a suitable buffer solution are reported. The method described was designed for later application to a study of the metabolism of the Veratrum viride alkaloids, but it demonstrates that polarographic analysis may be utilized satisfactorily in alkaloidal determination if the pure alkaloids are present in uncontaminated solutions. The Veratrum viride alkaloids investigated yielded characteristic reduction waves in at least two stages in the pH range studied.
Side Information Generation for Distributed Video Coding Using Spatiotemporal Joint Bilinear Upsampling

Distributed video coding presents a viable solution for power-constrained multimedia communication. However, its relatively low coding efficiency compared to the conventional video coding schemes remains a challenging issue. The rate-distortion performance of distributed video coding is highly dependent on the quality of side information generated at the decoder and various techniques have been proposed to improve the side information quality in block-based and frame-based distributed video coding architectures. In this paper, a robust spatiotemporal joint bilateral upsampling based side information generation method is proposed. The proposed side information generation method is based on a block-based low-complexity distributed video coding architecture with adaptive block coding mode classification. A partially reconstructed Wyner-Ziv (WZ) frame with skip and key blocks is downsampled and spatiotemporal error concealment and joint bilateral upsampling are used to generate the side information. Simulation results show that the proposed method improves the quality of side information significantly while keeping low computational complexity.
Null mutation in the rhodopsin kinase gene slows recovery kinetics of rod and cone phototransduction in man

Rhodopsin kinase (RK), a specialized G-protein-coupled receptor kinase expressed in retina, is involved in quenching of light-induced signal transduction in photoreceptors. The role of RK in recovery after photoactivation has been explored in vitro and in vivo experimentally but has not been specifically defined in humans. We investigated the effects on human vision of a mutation in the RK gene causing Oguchi disease, a recessively inherited retinopathy. In vitro experiments demonstrated that the mutation, a deletion of exon 5, abolishes the enzymatic activity of RK and is likely a null. Both a homozygote and heterozygote with this RK mutation had recovery phase abnormalities of rod-isolated photoresponses by electroretinography (ERG); photoactivation was normal. Kinetics of rod bleaching adaptation by psychophysics were dramatically slowed in the homozygote but normal final thresholds were attained. Light adaptation was normal at low backgrounds but became abnormal at higher backgrounds. A slight slowing of cone deactivation kinetics in the homozygote was detected by ERG. Cone bleaching adaptation and background adaptation were normal. In this human in vivo condition without a functional RK and probable lack of phosphorylation and arrestin binding to activated rhodopsin, reduction of photolyzed chromophore and regeneration processes with 11-cis-retinal probably constitute the sole pathway for recovery of rod sensitivity. The role of RK in rods would thus be to accelerate inactivation of activated rhodopsin molecules that in concert with regeneration leads to the normal rate of recovery of sensitivity. Cones may rely mainly on regeneration for the inactivation of photolyzed visual pigment, but RK also contributes to cone recovery.
Adhesive Point-Bonded Spunbond Fabrics:

Adhesive technology has improved enormously in the few past decades, so adhesive point-bonding of spunbond fabrics has been given a fresh look to ascertain whether thermal point-bonding may have a ...
Molecular Gas Radiation in a Laminar or Turbulent Pipe Flow

The temperature profile and the radiative and convective wall-heat fluxes for a hydro-dynamically established flow of a nongray gas in a cylinder are calculated numerically for laminar or turbulent flow. Turbulent eddy viscosity is represented by a two-region model having a near-wall-region and a far-from-wall region. Gas properties are represented by the exponential-winged band model. Qualitatively the results for a gas with a single major band agree with a previous solution for a cylinder with internal heat generation.
Consistency properties and set based logic programming

Blair et al. (2001) developed an extension of logic programming called set based logic programming. In the theory of set based logic programming the atoms represent subsets of a fixed universe X and one is allowed to compose the one-step consequence operator with a monotonic idempotent operator O so as to ensure that the analogue of stable models in the theory are always closed under O. Marek et al. (1992, Ann Pure Appl Logic 96:231---276 1999) developed a generalization of Reiter's normal default theories that can be applied to both default theories and logic programs which is based on an underlying consistency property. In this paper, we show how to extend the normal logic programming paradigm of Marek, Nerode, and Remmel to set based logic programming. We also show how one can obtain a new semantics for set based logic programming based on a consistency property.
Compositional regulation of poly(lysine-g-(lactide-b-ethylene glycol))-DNA complexation and stability.

The search for an effective nonviral gene therapy vector has revealed several significant hurdles, such as transient expression and cytotoxicity, that impede the success of these systems. A terpolymer of poly(lysine-g-(lactide-b-ethylene glycol)) [pK-g-p(LL-b-EG)] has been developed, which is capable of stably packaging DNA with significantly less polycation than unmodified polylysine (pK) systems. A comparison of unmodified pK (DP=14, Mw=2930) to pK grafted with p(LL-b-EG) (Mw tot=7500) showed that the minimum amine/phosphate ratio (N:Pmin) needed for complete DNA condensation was reduced by 50%. However, when the molecular weight of pK was reduced (DP=4, Mw=838), there was evidence of terpolymer interference with DNA condensation. Increasing the number of grafted p(LL-b-EG) chains produced a similar result of incomplete DNA condensation. All terpolymer formulations produced complexes with DNA that had greater resistance to salt-induced dissociation and short-term exchange with excess DNA. Terpolymer–DNA complexes exhibited approximately zero-order plasmid release profiles over a period of 6 weeks. The rate of release was dependent on the complex N:P ratio as well as the molecular weights of pLL and pK. The ability to use terpolymer composition to control complex stability and controlled release can provide a means for system optimization for sustained expression profiles of exogenous DNA.
Edward P. Morgan, What Really Happened to the 1960s: How Mass Media Culture Failed American Democracy

Faulkner's famous line, “the past is never dead; it's not even past,” provides an apt, uncomplimentary epigram for much scholarship on the 1960s, which is still infected by the twin desires to cond...
Impact of computational fluid dynamics on development test facilities

The impact of computational fluid dynamics (CFD) on the traditional role of aeronautical ground test facilities over the next 15 years is assessed via a National Research Council study. More powerful scientific computers and more efficient numerical algorithms should result in the ability to practically compute the flowfield about a complete aircraft with the Reynolds-averaged Navier-Stokes equations at a unit cost three orders of magnitude lower than at present. No dramatic change in the cost of testing in ground facilities is foreseen because more efficient computer-enhanced facility operation is partially offset by increased power and labor costs. From the user viewpoint, the risk in development of a new aircraft or engine is so great that use of proven methods of verification by means of test facilities will not change significantly. In the next 15 years CFD and ground test facilities will be utilized in a complementary rather than competitive mode of obtaining design data and the end result will be a better product.
Chronic Finger Dermatitis After Trauma

REPORT OF A CASE A 43-year-old man with no history of skin disease had a laceration and crush injury to his left middle finger, requiring tendon repair. During healing, a pruritic vesicular eruption developed that was limited to this site. Trials of topical corticosteroids and topical and oral antibiotics led to no improvement over 6 months. During that time, the patient was on medical leave because of intractable dermatitis and because of the nature of the injury. He was then referred for evaluation. On examination, there were multiple pinpoint vesicles circumferentially on the left middle finger, with secondary crusting (Figure 1). There were no notable lesions elsewhere. Recent topical therapy consisted of desoximetasone ointment, betamethasone ointment, bandages, and plain white cotton gloves. The results of a potassium hydroxide preparation were negative, and a bacterial culture yielded coagulase-negativeStaphylococcusspecies. What is your diagnosis? Is there a procedure you would choose
Whole-gut transit scintigraphy in the evaluation of small-bowel and colon transit disorders

Scintigraphic methods for performing gastric emptying and colon transit studies are now well standardized. Although not as well established, several methods have been proposed for measuring small-bowel transit. The measurement of orocecal transit time appears to be a practical scintigraphic measurement of small-bowel transit. When combined into a single test of gastric emptying, small-bowel, and colon transit, whole-gut transit scintigraphy is an important, noninvasive tool for documenting dysmotility of any segment of the gastrointestinal tract. Despite attempts to simplify the study, whole-gut transit scintigraphy still requires a significant commitment of time and equipment. As with other gastrointestinal studies, each laboratory must determine which protocol best fits its clinical needs, equipment, and staffing. Attention must be paid to adhere to established protocols, or normal values will need to be determined for each laboratory. Despite these difficulties, whole-gut transit scintigraphy now represents an important clinical tool for the evaluation of patients with a wide range of abdominal complaints.
Intermediate-range order in glasses

Abstract Intermediate-range order in glasses exists in different forms in molecular glasses, pure and modified network glasses, and fast ion conducting glasses. Recent work has shown that both intermediate-range order and ionic conductivity in glasses is enhanced by increasing the free volume of the network.
A new criterion for brittle-to-ductile fracture transition

The phenomenon of brittle-to-ductile fracture in metals has been examined on the basis of the mechanics of stable crack growth. The analysis indicates that the experimentally observed tearing modulus, TR, is the result of the competition between the intrinsic tearing resistance of the material and a tearing term induced by crack extension, both of which can be expressed in terms of the normalized parameter, Ω = Eelf/σ0, where E, elfandσ0 are the elastic modulus, intrinsic fracture strain, and flow stress, respectively. Through the use of the tearing modulus, a new criterion of brittle-to-ductile fracture is proposed, and the boundary for the transition of fracture modes is predicted and compared with the experimental results of Al-Fe-X alloys, steels, conventional Al-, Ti-, and Ni-alloys in the forms of a fracture mode diagram and a tearing resistance, TR-Ω, curve. The proposed methodology is then applied to explain the brittle-ductile transition phenomena resulting from strain rate, temperature, and inclusion effects as well as those associated with grain boundary embrittlement, temper embrittlement, hydrogen embrittlement, and cleavage.
Vibrational frequencies and normal modes of Co adsorbed on Ni(001)

Abstract The vibrational modes of CO adsorbed on a Ni(001) metal surface have been obtained using two different cluster models to represent the on-top and bridge-bonding situations. New modes, not previously available in the literature, are obtained for the bridge cluster.
Matrix-independent separation of rare-earth elements and yttrium from geological materials using constant calcium content-oxalate precipitation and cation exchange for determination by high-resolution inductively coupled plasma atomic emission spectrometry (ICP-AES)

Abstract Inductively coupled plasma atomic emission spectrometry (ICP-AES) is a precise and accurate analytical technique for determination of rare-earth elements (REE) in geologic materials provided the REE are separated from matrix elements. The separation method reported here uses cation exchange following an oxalate precipitation separation. Oxalate precipitation separates REE and Y with Ca from other matrix elements. Calcium oxalate is an effective carrier for REE, but is much more effective for light and middle REE (LREE and MREE) than for heavy REE (HREE). Complete REE recovery (especially of HREE) requires a sufficiently high Ca content in the sample. The method used here is to bring each sample (1 g) up to a Ca content of 107 mg by addition of calcium carbonate prior to sample digestion. Subsequent ion exchange with a mixed resin gives complete recovery of REE and Y (and in some cases Sc) without modification for sample type because the salt load is constant no matter what the starting material. Analysis of nine REE, Y and Sc is carried out using a very high-resolution sequential scanning ICP-AES system. High resolution minimizes RE inter-element interferences, and use of mixed-element standards (mixed in geologic proportions) minimizes corrections, usually to a negligible level. Analyses of U.S.G.S. standard reference materials BHVO- 1 , DNC- 1 and TLM- 1 compare well with published values for REE and Y. Recovery of Sc is apparently not always complete.
Fundamental limitations of slow-light optical buffers

We show that slow-light optical delay-line buffers are constrained by fundamental physical limitations. We compare the capabilities of a variety of buffer technologies including electromagnetically induced transparency, population pulsations, photonic crystal filters, and fibre-based delay lines.
The systolic J-M stroke displacement and gram-centimeters values of fifty-one normal males from an ULF pendulum ballistocardiographic system

Abstract 1. 1. The J-M displacement and Mass · Displacement values of 51 normal male subjects from an ultralow frequency pendulum ballistocardiographic system have been given. 2. 2. These values exceed those of previous studies. 3. 3. The ballistocardiographic Mass · Displacement value thus obtained is related to the internal cardiovascular mass · displacement value. Their degree of correlation remains to be established, particularly in regards to equating the internal cardiovascular mass and displacement values individually.
Approaches to evaluating reproductive hazards and risks.

Abstract Development of approaches to risk assessment for reproductive toxicity has aided in the critical evaluation of the scientific basis for interpretation of data and the description of assumptions underlying the process. In addition, it has helped to standardize, to the extent possible, the use of qualitative and quantitative data in the hazard identification and dose-response processes and to identify research needed to fill gaps in the available database. The standard study protocols for evaluating reproductive and developmental hazards include developmental toxicity studies and both short-term and longer-term reproductive studies. These study protocols have been in use for several decades, but development of risk assessment approaches has prompted the recommendation of additional end point measures to these protocols. These include evaluation of specific neurologic and behavioral function of offspring following prenatal and postnatal exposure, evaluation of sperm production and quality, reproductive organ weights, and more in-depth testicular histopathology in males, as well as measures of age at vaginal opening, vaginal cytology, oocyte toxicity, time to mating, gestation length, and reproductive organ weights in females. Current approaches to risk assessment in reproductive toxicity involve the determination of a no-observed-adverse-effect level (NOAEL) and the application of uncertainty factors (UFs) to account for differences between the experimental animal species and humans, variability in sensitivity within the human population, and other factors as necessary to derive the reference dose (RfD), or a specified RfD for developmental toxicity to account for the short period of exposure required.(ABSTRACT TRUNCATED AT 250 WORDS)
Planting Seed Density in Relation to Cotton Emergence and Yield

Cotton (Gossypium hirsutum L.) planting seed density has been related to seedling emergence and vigor, although its effects on yield are not clearly understood. Seed lots of the cultivar ‘DP90’ were separated into four density classes using a gravity separation table. These seed classes were evaluated along with an undivided seed sample and a sample from processed seed selected for commercial use. The seed classes were planted at three planting rates in seven tests conducted from 1983 to 1985 at Maricopa, Marana, and Safford, AZ. The soils at these locations are Typic Camborthids, Thermic Torrifluvents, and Typic Torrifluvents, respectively. The lowest density seed had significantly lower standard and cold germination test results; however, there were no differences among the other five seed classes in 2 of the 3 yr. Field emergence of the highest density seed was significantly greater than that of the other density classes for the seven tests combined, and was significantly lower for the lowest density seed. Lint yields produced by plants from the highest density seed were significantly greater than those of the four other seed classes, and the lowest density seed produced significantly lower yields. There were no significant interactions between planting seed density and planting rate for yield. The results indicate that cotton planting seed quality could be improved slightly by selecting higher density seed Arizona Agric. Exp. Stn. Journal Article no. 4044.
The operational amplifier as a laboratory tool

The ?operational amplifier? as it is usually referred to in computer terminology has proved its versatility and usefulness as the backbone of modern electronic differential analyzers. In a rapidly increasing number of engineering offices, schools, and laboratories, these devices are available either in small computing installations or as separate plug-in units. It is the purpose of this paper to describe briefly their operation and to show how their usefulness may be extended beyond the usual computing applications. The applications described are suggested by a point of view which is certainly not new, but which does not seem to have been exploited to its fullest extent.
Boundary Layers on Sobolev–Besov Spaces and Poisson's Equation for the Laplacian in Lipschitz Domains

We study inhomogeneous boundary value problems for the Laplacian in arbitrary Lipschitz domains with data in Sobolev–Besov spaces. As such, this is a natural continuation of work in [Jerison and Kenig,J. Funct. Anal.(1995), 16–219] where the inhomogeneous Dirichlet problem is treated via harmonic measure techniques. The novelty of our approach resides in the systematic use of boundary integral methods. In this regard, the key results are establishing the invertibility of the classical layer potential operators on scales of Sobolev–Besov spaces on Lipschitz boundaries for optimal ranges of indices. Applications toLp-based Helmholtz type decompositions of vector fields in Lipschitz domains are also presented.
The Impact of Development, the Commercialization of Agriculture, and Economic Dependency on Women's Participation in Agricultural Production

The post‐World War ? period has been one of intense development activity throughout the world. Lesser developed countries have showed significant economic growth throughout this time‐span. Among the many consequences which are attributed to development, changes in gender relations are often mentioned. However, prior research has been unable to establish conclusively how economic development is related to gender inequality, particularly as this is referenced by women's participation in important economic activities. For example, some researchers have found that as development increases, women's participation in and return from the economy declines, others that it increases, and several have suggested it first declines then increases. Similar uncertainties exist about how an increasing emphasis on producing goods for export, and the often‐accompanying reliance on foreign investment, affects women's work. Recent research also suggests that the consequences of development are more diverse than previously thought. Recognition of the diversity requires greater specification of the links between developmental diversity and women's labor force participation.
Non-periodic currents: their properties, identification and compensation fundamentals

Before the area of power electronics was developed, nonperiodic currents occurred in distribution systems, apart from arc furnaces supply, mainly during switching and faults. Now, such currents are produced at normal operation of some power electronics equipment. Power electronics enables very fast control of processes and energy flow. Nonperiodic currents are a by-product of such a fast control. Identification of nonperiodic currents and their compensation is the subject of this paper. The paper discusses the main properties of nonperiodic currents, provides their classification and introduces a concept of coperiodic, noncoperiodic and quasi-periodic currents as well as the concept of interharmonic noise and quasi-harmonics. The paper provides fundamentals of quasi-periodic current compensation and discusses a hybrid control algorithm of a hybrid compensator.
The roles of pore ring and plug in the SecY protein-conducting channel.

The protein-conducting channel, or translocon, is an evolutionarily conserved complex that allows nascent proteins to cross a cellular membrane or integrate into it. The crystal structure of an archaeal translocon, the SecY complex, revealed that two elements contribute to sealing the channel: a small “plug” domain blocking the periplasmic region of the channel, and a pore ring composed of six hydrophobic residues acting as a constriction point at the channel's center. To determine the independent functions of these two elements, we have performed molecular dynamics simulations of the native channel as well as of two recently structurally resolved mutants in which portions of their plugs were deleted. We find that in the mutants, the instability in the plug region leads to a concomitant increase in flexibility of the pore ring. The instability is quantified by the rate of water permeation in each system as well as by the force required for oligopeptide translocation. Through a novel simulation in which the interactions between the plug and water were independently controlled, we find that the role of the plug in stabilizing the pore ring is significantly more important than its role as a purely steric barrier.
PNZIP Is a Novel Mesophyll-Specific cDNA That Is Regulated by Phytochrome and a Circadian Rhythm and Encodes a Protein with a Leucine Zipper Motif

We isolated and characterized a novel light-regulated cDNA from the short-day plant Pharbitis nil that encodes a protein with a leucine (Leu) zipper motif, designated PNZIP (Pharbitis nil Leu zipper). The PNZIP cDNA is not similar to any other gene with a known function in the database, but it shares high sequence homology with an Arabidopsis expressed sequence tag and to two other sequences of unknown function from the cyanobacterium Synechocystis spp. and the red alga Porphyra purpurea, which together define a new family of evolutionarily conserved Leu zipper proteins. PNZIP is a single-copy gene that is expressed specifically in leaf photosynthetically active mesophyll cells but not in other nonphotosynthetic tissues such as the epidermis, trichomes, and vascular tissues. When plants were exposed to continuous darkness, PNZIP exhibited a rhythmic pattern of mRNA accumulation with a circadian periodicity of approximately 24 h, suggesting that its expression is under the control of an endogenous clock. However, the expression of PNZIP was unusual in that darkness rather than light promoted its mRNA accumulation. Accumulation of PNZIP mRNA during the dark is also regulated by phytochrome, since a brief exposure to red light in the middle of the night reduced its mRNA levels. Moreover, a far-red-light treatment at the end of day also reduced PNZIP mRNA accumulation during the dark, and that effect could be inhibited by a subsequent exposure to red light, showing the photoreversible response attributable to control through the phytochrome system.
Formation of SnS nanoflowers for lithium ion batteries

SnS nanoflowers containing hierarchically organized nanosheet subunits were synthesized using a simple solution route, and they function as lithium ion battery anodes that maintain high capacities and coulombic efficiencies over 30 cycles.
A Two-Level Theory of Presidential Instability

This article analyzes the conditions that facilitate the ousting of Latin American presidents and the mechanisms that prevent their downfall. Drawing lessons from the impeachment of Paraguayan president Fernando Lugo, it extends previous arguments about the “legislative shield” to show that the same forces that sometimes conspire to terminate an administration at other times work to resist its demise. The argument underscores the interaction between legislators and social movements, two prominent actors in the literature on presidential instability. The article presents a two-level theory to identify possible configurations of mass and legislative alignments, and tests some implications of the theory with data for 116 Latin American presidents over 28 years. Multiple comparison tests based on random effects logistic models show that popular protests can be neutralized by strong support in Congress, and hint at the possibility that legislative threats can be neutralized by loyal demonstrators in the streets.
Steady-State Stability Analysis of HVDC Systems with Digital Control

This paper derives and linearizes a mathematical model of an HVDC link with digital control. The discrete state equations for the multi-variable control with various pure time-delays are established by using a state-averaging method. The stability of operation has been evaluated analytically for small-signal disturbances. The effects of various parameters of control, dc link and the receiving ac system on stability of the overall system are discussed.
Two dimensional ultrasound scanning of excised brains—I. Normal anatomy

Abstract This study demonstrated techniques for visualization of detailed brain anatomy with two dimensional ultrasound. The use of large aperture focused ultrasound transceivers appears to be essential for displaying the outlines of thalamus, internal capsule and substantial nigra in addition to those of the ventricles. The ability to vary grey scale and edge enhancement using either linear or logarithmic amplification through a scan converter assisted in identification of anatomical structural detail. It was most clearly visualized when the images were displayed with accentuation of edge enhancement. Brain position during ultrasound scanning was also important for maximal visualization of structural detail. Anatomical studies are useful in clinical application of two dimensional ultrasound brain visualization, to assure maximum diagnostic information with minimum scan time. The development of ultrasound diagnostic instruments and techniques is expected to add valuable information to computer assisted tomography, isotope brain scanning and cerebral angiography in the management of brain disorders, particularly in infants.
The Potential For Wave Disturbance in Shallow Florida Lakes

Bachmann.R. W., M. V. HoyerandD. E. CanfieldJr. 2000. The potential for wavedisturbance in.hallow Floridalakes. Lake and Reserv. Manage. 16(4):281-291. We applied wave theory to calculate the extent and frequency that we would expectwav~vensurface water movementsto disturb the sediments in.36 Floridalakes coveringa broadrange ofsurface areasand meandepths. The calculated per cent ofthe lakebedsubject to wave disturbance at one time oranother ranged from 6 to 100% and the per cent of the time 50% of the lakebed was disturbed ranged from 0 to 65%. The large Florida lakes. Apopka, Okeechobee, and Istokpoga showed high levels of calculated wave disturbance, which was consistent with the conclusions ofprevious investigations. Historic waterlevel fluctuations in LakeApopkawerecalculatedto have IJIajor effects on wave disturbance in that lake. The dynamic ratio (the square root oflake surface area in sqJJare kilometeR divided by the meandepth in meteR) was significantly related to various measuresofwave disturbance in oursample lakes. For lakes with ratio values above about 0.8 the entire lakebed was subject to wave disturbance at least some of the time. The dynamic ratio was also related to lake water quality. We found that increases in the dynamic ratio were significantly related to decreases in water quality as measured by total phosphorus,total nitrogen. chlorophyll, and Secchi disk depth. Calculations of wind disturbance by waves need to be modified in lakes with extensive beds of macrophytes,where waterlevels change and in periods where climaticfluctuations result in changesinwind regimes.
Reliable long-lasting depression interacts with variable short-term facilitation to determine corticostriatal paired-pulse plasticity in young rats

Synaptic plasticity at corticostraital synapses is proposed to fine tune movment and improve motor skills. We found paired-pulse plasticity at corticostriatal synapses reflected variably expressed short-term facilitation blended with a consistent background of longer-lasting depression. Presynaptic modulation via neuotransmitter receptor activation was ruled out as a mechanism for long-lasting paired-pulse depression by examining the effect of selective receptor antagonists. EPSC amplitude and paired-pulse plasticity, however, was influenced by block of D2 dopamine receptors. Block of glutamate transport with l-transdicarboxylic acid (PDC) reduced EPSCs, possibly through a mechanism of AMPA receptor desensitization. Removal of AMPA receptor desensitization with cyclothiazide reduced the paired-pulse depression at long-duration interstimulus intervals (ISIs), indicating that AMPA receptor desensitization participates in corticostriatal paired-pulse plasticity. The low-affinity glutamate receptor antagonist cis-2,3-piperidine dicarboxylic acid (PDA) increased paired-pulse depression, suggesting that a presynaptic component also exists for long-lasting paired-pulse depression. Low Ca2+–high Mg2+ or BAPTA-AM dramatically reduced the amplitude of corticostriatal EPSCs and both manipulations increased the expression of facilitation and, to a lesser extent, they reduced long-lasting paired-pulse depression. EGTA-AM produced a smaller reduction in EPSC amplitude and it did not alter paired-pulse facilitation, but in contrast to low Ca2+ and BAPTA-AM, EGTA-AM increased long-lasting paired-pulse depression. These experiments suggest that facilitation and depression are sensitive to vesicle depletion, which is dependent upon changes in peak Ca2+ (i.e. low Ca2+–high Mg2+ or BAPTA-AM). In addition, the action of EGTA-AM suggests that basal Ca2+ regulates the recovery from long-lasting paired-pulse depression, possibly thourgh a Ca2+-sensitive process of vesicle delivery.
Is there a path beyond BOLD? Molecular imaging of brain function

The dependence of BOLD on neuro-vascular coupling leaves it many biological steps removed from direct monitoring of neural function. MRI based approaches have been developed aimed at reporting more directly on brain function. These include: manganese enhanced MRI as a surrogate for calcium ion influx; agents responsive to calcium concentrations; approaches to measure membrane potential; agents to measure neurotransmitters; and strategies to measure gene expression. This work has led to clever design of molecular imaging tools and many contributions to studies of brain function in animal models. However, a robust approach that has potential to get MRI closer to neurons in the human brain has not yet emerged.