cssi/SciSciGPT-SciSciNet huggingface dataset:
Tilting of the Cardiac Axis During Dobutamine Stress Echocardiography: Potential Marker for Ischemia.

Stress echocardiography is a tool for assessing the extent and severity of coronary artery disease (CAD) during physical or pharmacological stress. Transient worsening of regional left ventricular (LV) function during stress is a well-recognized abnormality of inducible ischemia. We present the case of a 57-year-old female with risk factors for CAD who was referred for a dobutamine stress echocardiogram for complaints of typical angina. It was interpreted as positive for inducible ischemia, but using unconventional criteria. Unfortunately, this study had reduced sensitivity due to LV hypertrophy. All LV wall segments were not clearly seen to comment on regional contractility, and an abnormal cardiac tilt from its axis was noted, suggestive of ischemia along the anteroseptal, anterior and lateral walls. Following this, a coronary angiogram showed diffuse CAD. The cardiac axis with the presence of a tilt as a potential measure of ischemia is previously unrecognized. The idea invokes a mathematical principle based on the direction and the magnitude of the vector of opposing walls during contractility. Simply implying that ischemic segments might contract in the same direction, vector magnitude will be less prominent; hence, “axial tilt” will occur. Prospective studies are needed to validate the feasibility and reproducibility of this abnormality in the assessment of ischemia and its viability in clinical practice.
Analysis of high-risk pedigrees identifies 11 candidate variants for Alzheimer's disease.

Introduction Analysis of sequence data in high-risk pedigrees is a powerful approach to detect rare predisposition variants. Methods Rare, shared candidate predisposition variants were identified from exome sequencing 19 Alzheimer's disease (AD)-affected cousin pairs selected from high-risk pedigrees. Variants were further prioritized by risk association in various external datasets. Candidate variants emerging from these analyses were tested for co-segregation to additional affected relatives of the original sequenced pedigree members. Results AD-affected high-risk cousin pairs contained 564 shared rare variants. Eleven variants spanning 10 genes were prioritized in external datasets: rs201665195 (ABCA7), and rs28933981 (TTR) were previously implicated in AD pathology; rs141402160 (NOTCH3) and rs140914494 (NOTCH3) were previously reported; rs200290640 (PIDD1) and rs199752248 (PIDD1) were present in more than one cousin pair; rs61729902 (SNAP91), rs140129800 (COX6A2, AC026471), and rs191804178 (MUC16) were not present in a longevity cohort; and rs148294193 (PELI3) and rs147599881 (FCHO1) approached significance from analysis of AD-related phenotypes. Three variants were validated via evidence of co-segregation to additional relatives (PELI3, ABCA7, and SNAP91). Discussion These analyses support ABCA7 and TTR as AD risk genes, expand on previously reported NOTCH3 variant identification, and prioritize seven additional candidate variants.
Structures, relative energies, and ligand dissociation energies of iridium carbonyl phosphine clusters

Abstract There is significant interest in the catalytic properties of substituted iridium carbonyl clusters but little thermodynamic information available characterizing them. The low-energy isomers of Ir x (PH 3 ) y (CO) z ( x = 1, 2, 4) were investigated with density functional theory and correlated molecular orbital theory at the coupled cluster CCSD(T) level. The relative energies and ligand dissociation energies were calculated. Differences in relative energies are consequences of both electronic and steric effects of the phosphines and carbonyls. The calculations predict three fundamental structural types for Ir 2 (PH 3 ) y (CO) z : C 2v , C 2 , and D 3d . Ten exchange–correlation functionals were used for the ligand dissociation energy calculations in addition to CCSD(T) for the smaller clusters. The ωB97X-D functional gave the most consistent ligand dissociation energies as compared with the CCSD(T) benchmark calculations, and, so it was used to predict the dissociation energies for larger clusters when CCSD(T) calculations were infeasible. The dissociation energies characteristic of Ir 4 (PH 3 ) y (CO) z were in the range of ∼30 to ∼60 kcal/mol. Dissociation of a bridging ligand often involved a hydrogen atom transfer from a phosphine to a coordinatively unsaturated iridium atom and a phosphine converting from a bridging site to an equatorial site. The products of such reactions are predicted to have lower relative energies than other isomers. Phosphines act as σ-electron donors, and there is a trend of an increase in carbonyl ligand dissociation energies as more phosphines are substituted in the small clusters.
Post-fire stand development of Austrocedrus-Nothofagus forests in northern Patagonia

In the rainshadow of the Andean Cordillera in northern Patagonia (ca 39° to 43°S) the steep west-to-east decline in precipitation is reflected by a dramatic gradient from rainforest through open woodlands to shruband bunchgrass-dominated steppe. A recent trend towards aridification of Patagonia and consequent westward expansion of xeric communities into the western rainforest district has been a persistent theme in the ecological literature for nearly 50 years. Specifically, it has been suggested that the xeric trees Austrocedrus chilensis and Nothofagus antarctica are extending their ranges westward and replacing the mesic Nothofagus dombeyi which dominates the rainforests. This hypothesis was investigated by analyzing stand age structures and patterns of tree radial growth along a west-to-east gradient of post-fire stands dominated by Nothofagus dombeyi and Austrocedrus chilensis.
A Surface Loop Covering the Active Site of Human Pancreatic Lipase Influences Interfacial Activation and Lipid Binding

The distinguishing feature of lipases is their increased activity at an oil-water interface, termed interfacial activation. X-ray crystallography of lipases suggested a mechanism for interfacial activation by revealing conformational changes in several surface loops that cover the active site. In one conformation, these loops prevented substrate from entering the active site, and, in the other conformation, movement of the loops opened the active site. We tested the role of the major surface loop, the lid domain, in human pancreatic lipase (hPL) function by creating deletions in this region and expressing the mutant proteins in baculovirus-infected insect cells. the mutants were tested for activity against tributyrin and triolein, colipase interaction, interfacial activation, and binding to tributyrin. The purified mutants had decreased activity against both tributyrin and triolein compared to wild-type hPL and did not show a preference for either substrate. Although colipase was required for maximum activity in the presence of bile salts, the mutants had significant activity against tributyrin, but not triolein, in the absence of colipase. Both mutants were active against monomers of tributyrin demonstrating that they did not require an interface for activity. Finally, both mutants had decreased binding to tributyrin particles. These results suggest that the lid domain in hPL mediates interfacial activation and influences interfacial binding.
On reducing compensator bandwidth of LQG/LTR control: an H ∞ - optimization approach

Due to lack of robustness, the Linear Quadratic Gaussian (LQG) approach to the design of control systems is enhanced by Loop Transfer Recovery (LTR) techniques. However, the robustness is recovered with the price paid to the unduly large or infinite bandwidth of the compensator. Such compensators are undesirable because plant output measurement noise is greatly amplified so as to degrade the system performance. A simple method is presented for reducing compensator bandwidth by H∞- optimization of a stable function which combines the usual sensitivity function difference with a weighted closed-loop transfer function from noise to plant input. An example is given to show the improvement achievable by this new design method.
Identification of nonlinear dynamical system using hierarchical clustering analysis and local linear models

This paper discusses the use of unsupervised learning and localized modeling to identify nonlinear dynamical systems from empirical series data. A finite-order nonlinear autoregressive (AR) model is constructed to capture the system dynamics. The embedded input space for the nonlinear AR model is partitioned into overlapped regions that are fine enough so that localized modeling techniques, such as local linear modeling, can approximate system dynamics well in each region. Subsequently, unsupervised learning, such as hierarchical clustering analysis, is used for partitioning the embedded input space to achieve the tradeoff between the model complexity and the approximation error. The performance of the proposed approach is evaluated on two numerical examples: (i) time series prediction; (ii) identification of SISO system. Simulation results demonstrate that the proposed approach can capture the nonlinear system dynamics well.
Effects of DNA mass on multiple displacement whole genome amplification and genotyping performance.

Background Whole genome amplification (WGA) promises to eliminate practical molecular genetic analysis limitations associated with genomic DNA (gDNA) quantity. We evaluated the performance of multiple displacement amplification (MDA) WGA using gDNA extracted from lymphoblastoid cell lines (N = 27) with a range of starting gDNA input of 1–200 ng into the WGA reaction. Yield and composition analysis of whole genome amplified DNA (wgaDNA) was performed using three DNA quantification methods (OD, PicoGreen® and RT-PCR). Two panels of N = 15 STR (using the AmpFlSTR® Identifiler® panel) and N = 49 SNP (TaqMan®) genotyping assays were performed on each gDNA and wgaDNA sample in duplicate. gDNA and wgaDNA masses of 1, 4 and 20 ng were used in the SNP assays to evaluate the effects of DNA mass on SNP genotyping assay performance. A total of N = 6,880 STR and N = 56,448 SNP genotype attempts provided adequate power to detect differences in STR and SNP genotyping performance between gDNA and wgaDNA, and among wgaDNA produced from a range of gDNA templates inputs.
Automatic derivation of linear algebra algorithms with application to control theory

It is our belief that the ultimate automatic system for deriving linear algebra libraries should be able to generate a set of algorithms starting from the mathematical specification of the target operation only. Indeed, one should be able to visit a website, fill in a form with information about the operation to be performed and about the target architectures, click the SUBMIT button, and receive an optimized library routine for that operation even if the operation has not previously been implemented. In this paper we relate recent advances towards what is probably regarded as an unreachable dream. We discuss the steps necessary to automatically obtain an algorithm starting from the mathematical abstract description of the operation to be solved. We illustrate how these steps have been incorporated into two prototype systems and we show the application of one the two systems to a problem from Control Theory: The Sylvester Equation. The output of this system is a description of an algorithm that can then be directly translated into code via API's that we have developed. The description can also be passed as input to a parallel performance analyzer to obtain optimized parallel routines [5].
Interpreting Ancient Figurines: The Questions We Ask of Images

Figurines from different contexts may be physically similar or they may resemble one another as assemblages. For instance, contexts of recovery may be similar or predominant themes may be shared. The question I am pursuing is how – or whether – such observations should affect our social interpretations. The challenge is to reformulate material similarities into social terms without overburdening them so heavily with partisan theory that our conclusions are from that point foreordained and archaeological evidence no longer matters. Our newly acquired contextualist strategy prompts us to begin by considering the resemblant traits in their original contexts, in interplay with other traits. We would then compare the resulting contextualizations. It is a promising strategy, but the way forward still seems difficult. Let us therefore jump to the end-products of analyses. Sometimes the social interpretations of similar figurines from unrelated contexts resemble one another. Is it possible to identify the source of such convergence? Let us consider a specific case. Five papers find that prehistoric figurines from different time periods in different parts of the world depict women at different stages of their lives. Patricia Rice argues that figurines of the European Paleolithic “represent women of different ages in proportion to their probable actual frequency in the population.” According to Avi Gopher and Estelle Orrelle, Yarmukian pebble figurines from the Southern Levant some twelve millennia later comprise a record of age differences among females “from girlhood up to perhaps menopause.”
Social Structure, Anomie, and National Levels of Homicide

Merton’s “Social Structure and Anomie” seeks to explain how “socio-cultural” influences exert “definite pressures” to engage in non-conformity. Despite having a significant influence, few studies have assessed the degree to which Merton’s propositions explain cross-national variation in levels of crime. Using data on national levels of homicide, data from the World Values Survey, and other structural controls, the present study assesses the degree to which deinstitutionalization, demoralization, and blocked opportunity interact to explain crime cross-nationally. Results provide a high degree of support for Merton’s assertion that societal types characterized by relatively high levels of materialism and/or demoralization or deinstitutionalization suffer from higher levels of homicide. However, there is less support for Merton’s assertion that inequality interacts with various societal patterns of means/ends integration in a meaningful way. Findings and implications for the utility of classical anomie as a ...
Tec family kinases Itk and Rlk / Txk in T lymphocytes: cross-regulation of cytokine production and T-cell fates

Developing thymocytes and T cells express the Tec kinases Itk, Rlk/Txk and Tec, which are critical modulators of T-cell receptor signaling, required for full activation of phospholipase Cγ, and downstream Ca(2+) and ERK-mediated signaling pathways. Over the last 10 years, data have implicated the Tec family kinases Itk and Rlk/Txk as important regulators of cytokine production by CD4(+) effector T-cell populations. Emerging data now suggest that the Tec family kinases not only influence cytokine-producing T-cell populations in the periphery, but also regulate the development of distinct innate-type cytokine-producing T-cell populations in the thymus. Together, these results suggest that the Tec family kinases play critical roles in helping shape immune responses via their effects on the differentiation and function of distinct cytokine-producing, effector T-cell populations.
Control of Drosophila head segment identity by the bZIP homeotic gene cnc

Mutational analysis of cap'n'collar (cnc), a bZIP transcription factor closely related to the mammalian erythroid factor NF-E2 (p45), indicates that it acts as a segment-specific selector gene controlling the identity of two cephalic segments. In the mandibular segment, cnc has a classical homeotic effect: mandibular structures are missing in cnc mutant larvae and replaced with duplicate maxillary structures. We propose that cnc functions in combination with the homeotic gene Deformed to specify mandibular development. Labral structures are also missing in cnc mutant larvae, where a distinct labral primordia is not properly maintained in the developing foregut, as observed by the failure to maintain and elaborate patterns of labral-specific segment polarity gene expression. Instead, the labral primordium fuses with the esophageal primordium to contribute to formation of the esophagus. The role of cnc in labral development is reciprocal to the role of homeotic gene forkhead, which has an identical function in the maintenance of the esophageal primordium. This role of homeotic selector genes for the segment-specific maintenance of segment polarity gene expression is a unique feature of segmentation in the preoral head region of Drosophila.
Electrical conductivity in two mixed-valence liquids

Two different room-temperature liquid systems were investigated, both of which conduct a DC electrical current without decomposition or net chemical transformation. DC electrical conductivity is possible in both cases because of the presence of two different oxidation states of a redox-active species. One system is a 1 : 1 molar mixture of n-butylferrocene (BuFc) and its cation bis(trifluoromethane)sulfonimide salt, [BuFc+][NTf2−], while the other is a 1 : 1 molar mixture of TEMPO and its cation bis(trifluoromethane)sulfonimide salt, [TEMPO+][NTf2−]. The TEMPO–[TEMPO+][NTf2−] system is notable in that it is an electrically conducting liquid in which the conductivity originates from an organic molecule in two different oxidation states, with no metals present. Single-crystal X-ray diffraction of [TEMPO+][NTf2−] revealed a complex structure with structurally different cation–anion interactions for cis- and trans [NTf2−] conformers. The electron transfer self-exchange rate constant for BuFc/BuFc+ in CD3CN was determined by 1H NMR spectroscopy to be 5.4 × 106 M−1 s−1. The rate constant allowed calculation of an estimated electrical conductivity of 7.6 × 10−5 Ω−1 cm−1 for BuFc–[BuFc+][NTf2−], twice the measured value of 3.8 × 10−5 Ω−1 cm−1. Similarly, a previously reported self-exchange rate constant for TEMPO/TEMPO+ in CH3CN led to an estimated conductivity of 1.3 × 10−4 Ω−1 cm−1 for TEMPO–[TEMPO+][NTf2−], a factor of about 3 higher than the measured value of 4.3 × 10−5 Ω−1 cm−1.
MGLAIR agents in virtual and other graphical environments

We are demonstrating several intelligent agents built according to the MGLAIR (Modal Grounded Layered Architecture with Integrated Reasoning) agent architecture. The top layer of MGLAIR is implemented in SNePS and its acting subsystem, SNeRE (the SNePS Rational Engine). The major demonstration will be act 3 of The Trial The Trail, an interactive drama running on an immersive Virtual Reality system, in which a human participant interacts with several MGLAIR actor-agents. We will also demonstrate several olher MGLAIR agents that operate in non-VR graphical environments. All these agents illustrate our approach to building agents with integrated first-person, on-line reasoning and acting.
(n-3) Fatty Acids and Infectious Disease Resistance

The current view of the manner in which (n-3) polyunsaturated fatty acids (PUFA) affect the immune system is centered on their ability to alter cytokine production and secondarily to diminish eicosanoid biosynthesis. The purpose of this article is to review the evidence that (n-3) PUFA affect host infectious disease resistance. Although there have been a few human clinical trials involving (n-3) PUFA and human infectious disease, the data are equivocal and the study designs confounded by the simultaneous inclusion of other immunonutrients (i.e., arginine and nucleotides) with the (n-3) PUFA. Thus, this review focuses on animal feeding trials that include an in vivo challenge of the host with a live infectious agent. Host survival and pathogen clearance are the most common end points measured in these studies. The data suggest that (n-3) PUFA can both improve and impair host resistance to a number of pathogens. However, the data are still quite limited in breadth and depth. For those pathogens for which data exist, the number of published studies in general does not exceed two or three. Emphasis is placed on defining important microbiological and immunological differences in various host-pathogen interactions that might help explain the incongruity in the findings published to date. The authors believe that direct examination of (n-3) PUFA on human infectious disease resistance is warranted.
Midline Thalamic Region: Widespread Excitatory Input to the Entorhinal Cortex and Amygdala

The midline thalamus has a role in memory formation and has well described projections to multiple limbic sites including the hippocampus, amygdala, and entorhinal cortex. Stimulation of this region evokes excitatory responses in the CA1 region of the hippocampus, but nothing is known about the nature of thalamic influence on other limbic sites such as the entorhinal cortex and the amygdala. In this study we electrically stimulated the midline thalamus in anesthetized rats to determine whether responses could be evoked in the amygdala or entorhinal cortex. In addition we examined the distribution of the responses within the target regions as well as the effect of short interval paired or high-frequency tetanizing stimulation. We found reproducible responses in the entorhinal cortex and the amygdala with a distribution of responses that matched the described synaptic input from the thalamus. In addition, high-frequency stimulation induced a consistent long-term potentiation in the two sites. Paired stimulation resulted in depression of the test response in the amygdala, but a facilitation in the entorhinal cortex. These findings indicate that the midline has a significant monosynaptic excitatory influence in the amygdala and the entorhinal cortex. Combined with the previous work in the hippocampus, this study suggests that the midline thalamus plays a significant role in limbic physiology and may serve to synchronize activity in this system.
Carcinogenicity Test of Six Nitrosamides and a Nitrosocyanamide Administered Orally to Rats

Six nitrosamides [ethylnitrosourea (ENU), 2-hydroxyethylnitrosourea (HENU), carboxymethylnitrosourea, 1-nitroso-5,6-dihydrouracil (NDHU), 1-nitrosohydantoin, and N-methyl-N-nitrosobenzamide (MNB)] and ethylnitrosocyanamide (ENC) were administered chronically in sodium citrate-buffered drinking water to MRC Wistar rats. ENU induced tumors of the reticuloendothelial system (RES) (50% incidence), mammary glands, and large intestine. NDHU in drinking water produced hepatocellular carcinomas (96% incidence), but NDHU injected ip caused mostly tumors at the injection sites (54% incidence). HENU produced bone tumors (38% incidence) and RES tumors (28% incidence). ENC produced nasal cavity tumors (36% incidence). Papillomas and/or carcinomas of the forestomach, tongue, and pharynx were induced by most of the compounds, with the highest incidence in the forestomach (47% for MNB); these tumors were attributed to local action when the compounds were ingested. Carcinogenicity was not quantitatively correlated with direct mutagenicity for Salmonella typhimurium TA1535.
Fifty years of progress in water relations research.

Many of the basic concepts dealing with soil and plant water relationships were in existence 50 years ago, but were inadequately presented in the textbooks of that time. There has been a marked increase in the amount of work done in this field during recent decades, but much of it involves advances in understanding the concepts already in existence. Three of the most important advances in the field of water relations are: (a) acceptance of the term, water potential, to describe the free energy status of water in soil and plants; (b) marked improvement in methods of measuring water potential and stomatal resistance; and (c) use of the concept of water flow in the soil-plant system as analogous to flow of electricity in a conducting system.A number of interesting and important problems remain to be studied. Of these, probably the most important is to learn why mild water stress of less than - 10 bars can affect various enzyme-mediated metabolic processes. Plant scientists in applied fields also need to learn more about the causes of differences in ability to tolerate drought among plants of various kinds. There is uncertainty concerning the relative magnitude of the resistances to water flow in various parts of the soil-plant system and concerning the causes of the apparent changes in resistance to water flow with increase in rate and with time of day. More information also is needed concerning the role of growth regulators synthesized in roots and the importance of the older, suberized roots in the absorption of water and mineral nutrients.
Genetic and physical interaction suggest that BARREN STALK1 is a target of BARREN INFLORESCENCE2 in maize inflorescence development

Summary Organogenesis in plants is controlled by polar auxin transport. In maize (Zea mays), barren inflorescence2 (bif2) encodes a co-ortholog of the serine/threonine protein kinase PINOID (PID), which regulates auxin transport in Arabidopsis. In this paper, we report that the basic helix-loop-helix transcription factor BARREN STALK1 (BA1) is a putative target of BIF2, revealing a previously unknown function of BIF2 in the nucleus. Both bif2 and ba1 are required for axillary meristem initiation during inflorescence and vegetative development in maize. Using a yeast two-hybrid approach, we identified BA1 as an interacting partner with BIF2. We confirmed the interaction by in vitro pull-down assays, and demonstrated that BIF2 phosphorylates BA1 in vitro. Previously, RNA in situ hybridization showed that bif2 and ba1 are both expressed during axillary meristem initiation. Here, we heterologously expressed BIF2 and BA1, and found that they co-localize in the nucleus. Based on these findings, we propose that in addition to regulating auxin transport at the cell periphery, BIF2 also functions in the nucleus by interacting with BA1 to promote axillary meristem initiation. Double mutant analysis is consistent with these results, showing that bif2 and ba1 have overlapping as well as unique roles in inflorescence development.
Modeling Asphaltene Phase Behavior in Crude Oil Systems Using the Perturbed Chain Form of the Statistical Associating Fluid Theory (PC-SAFT) Equation of State†

Asphaltene precipitation and deposition can occur at different stages during petroleum production, causing reservoir formation damage and plugging of pipeline and production equipment. Predicting asphaltene flow assurance issues requires the ability to model the phase behavior of asphaltenes as a function of the temperature, pressure, and composition. In this paper, we briefly review some recent approaches to model asphaltene phase behavior. We also present a method to characterize crude oil, including asphaltenes using the perturbed chain form of the statistical associating fluid theory (PC-SAFT). The theory accurately predicts the crude oil bubble point and density as well as asphaltene precipitation conditions. The theory is used to examine the effects of gas injection, oil-based mud contamination, and asphaltene polydispersity on the phase behavior of asphaltenes. The analysis produces some interesting insights into field and laboratory observations of asphaltene phase behavior.
Observations on the Honji instability

Abstract A numerical investigation of three-dimensional sinusoidally oscillating flow around an infinitely long cylinder was conducted to examine the onset of the Honji instability and to gain insight into the mechanism that causes the Honji instability to arise. An attempt is made to quantify when the instability occurs using the dimensionless flow parameters of the Keulegan–Carpenter number (KC) and the Sarpkaya number (β). Through numerical analysis and an explanation of physics, it is shown that the Honji instability occurs through the mechanisms described by Lord Rayleigh, but is significantly different from the Taylor, Dean, and Gortler instabilities.
Site-Specific Differences in T Cell Frequencies and Phenotypes in the Blood and Gut of HIV-Uninfected and ART-Treated HIV+ Adults

Gastrointestinal T lymphocytes are critical for mucosal immunity and HIV pathogenesis, yet little is known about normal T cell numbers and phenotypes in different regions of the gut, or the degree to which ART can restore levels to those of HIV-uninfected individuals. To investigate these questions, we measured T cell frequencies and markers of memory, activation, anergy, and homing in the blood, ileum, and rectum of HIV- and ART-suppressed HIV+ adults. In HIV- individuals, T cell frequencies and phenotypes differed significantly between sites. Compared to HIV- adults, HIV+ adults had lower absolute CD4+T cell counts in the ileal lamina propria and lower relative CD4+T cell counts in the blood and ileum. In the gut, HIV+ adults had a higher proportion of CD38+ CD4+T cells, a lower proportion of terminally-differentiated effector cells, and, in the rectum, a higher proportion of CTLA-4+ CD4+T cells. In HIV+ individuals, relative CD4+T cell numbers in the ileum correlated with the proportion of CTLA-4+ CD4+T cells, whereas in the rectum, they tended to correlate with the proportion of circulating CD4+T cells expressing α4β7 or CCR6. Mechanisms of T cell reconstitution may differ throughout the gut, with homing contributing more in the rectum while ileal reconstitution is associated with mucosal CD4+T cell anergy.
Giant multipole resonances: perspectives after ten years

Abstract Nearly ten years ago evidence was published for the first of the so-called giant multipole resonances,.the giant quadrupole resonance. During the ensuing years research in this new field has spread to many nuclear physics laboratories throughout the world. A review of the present status of electric giant multipole resonances is provided in this presentation. Other presentations to this conference will describe magnetic giant resonances, giant resonance decay modes, and theoretical implications of the “new” giant resonances.
Comparison of onset and steady-state responses of hearing aids: implications for use of the auditory brainstem response in the selection of hearing aids.

Input-output (I/O) functions of hearing aids were measured in response to a 2000-Hz tone burst, having 0.5 ms rise/fall time and 10 ms duration. I/O functions, measured with a hearing-aid analyzer,...
Multiple volcanic episodes of flood basalts caused by thermochemical mantle plumes

The hypothesis that a single mushroom-like mantle plume head can generate a large igneous province within a few million years has been widely accepted. The Siberian Traps at the Permian-Triassic boundary and the Deccan Traps at the Cretaceous-Tertiary boundary were probably erupted within one million years. These large eruptions have been linked to mass extinctions. But recent geochronological data reveal more than one pulse of major eruptions with diverse magma flux within several flood basalts extending over tens of million years. This observation indicates that the processes leading to large igneous provinces are more complicated than the purely thermal, single-stage plume model suggests. Here we present numerical experiments to demonstrate that the entrainment of a dense eclogite-derived material at the base of the mantle by thermal plumes can develop secondary instabilities due to the interaction between thermal and compositional buoyancy forces. The characteristic timescales of the development of the secondary instabilities and the variation of the plume strength are compatible with the observations. Such a process may contribute to multiple episodes of large igneous provinces.
Autologous Chondrocyte Implantation: Surgical Technique and Outcomes

Chondral defects of the knee are frequently encountered during arthroscopy. For symptomatic lesions, several surgical options exist. Determining the best surgical option for a patient can be challenging for the treating surgeon. Autologous chondrocyte implantation (ACI) is an articular cartilage–restoring procedure that is commonly used to treat medium-to-large full-thickness cartilage lesions of the knee. It is a 2-stage procedure requiring cartilage biopsy, 4-6 weeks of in vitro chondrocyte expansion, followed by reimplantation. Short- and long-term outcome studies have been promising regarding patient satisfaction and durability. Realignment procedures, as indicated, have been shown to improve clinical outcome and longevity of the transplanted grafts. As newer generation techniques evolve, complications have been minimized.
Micropatterning of Proteins and Mammalian Cells on Indium Tin Oxide

This paper describes a novel surface engineering approach that combines oxygen plasma treatment and electrochemical activation to create micropatterned cocultures on indium tin oxide (ITO) substrates. In this approach, photoresist was patterned onto an ITO substrate modified with poly(ethylene) glycol (PEG) silane. The photoresist served as a stencil during exposure of the surface to oxygen plasma. Upon incubation with collagen (I) solution and removal of the photoresist, the ITO substrate contained collagen regions surrounded by nonfouling PEG silane. Chemical analysis carried out with time-of-flight secondary ion mass spectrometry (ToF-SIMS) at different stages in micropatterned construction verified removal of PEG-silane during oxygen plasma and presence of collagen and PEG molecules on the same surface. Imaging ellipsometry and atomic force microscopy (AFM) were employed to further investigate micropatterned ITO surfaces. Biological application of this micropatterning strategy was demonstrated through selective attachment of mammalian cells on the ITO substrate. Importantly, after seeding the first cell type, the ITO surfaces could be activated by applying negative voltage (-1.4 V vs Ag/AgCl). This resulted in removal of nonfouling PEG layer and allowed to attach another cell type onto the same surface and to create micropatterned cocultures. Micropatterned cocultures of primary hepatocytes and fibroblasts created by this strategy remained functional after 9 days as verified by analysis of hepatic albumin. The novel surface engineering strategy described here may be used to pattern multiple cell types on an optically transparent and conductive substrate and is envisioned to have applications in tissue engineering and biosensing.
1048 IMMUNE RESPONSE IN UREMIC AND POST-TRANSPLANT CHILDREN

Patients with chronic renal failure and renal allograft recipients have an increased incidence of infection. To define further the defect(s) in immune surveillance, children with chronic uremia, those on maintenance hemodialysis and those with well-functioning renal transplants were studied. Serum IgA, IgG and IgM levels, measured as an indicator of B-cell function, were reduced in all three groups. Intrinsic lymphocyte function was assayed by culturing patient cells in normal pooled plasma and stimulating them with phytohemagglutinin (PHA) or pokeweed mitogen (PWM). Mitogenic activity varied widely within each group but mean values were normal. The presence of an extrinsic inhibitor of lymphocyte activity was examined by culturing normal cells in patient plasma, again stimulating with PHA or PWM. Uremic plasma did not inhibit normal cell response to either PHA or PWM, but both pre- and post-dialysis plasma was markedly inhibitory. Plasma from transplant patients inhibited PHA response but not PWM response. Thus, uremic and transplant patients demonstrate a functional defect in B-cell activity. Although lymphocytes from these patients respond normally to mitogenic stimuli, plasma from dialysis (but not uremic patients) inhibits the mitogenic response of normal lymphocytes. Our data indicate that chronic hemodialysis affects humoral factors which influence lymphocyte activity. Immunosuppressive agents may contribute to the inhibition observed in transplant patient plasma.
The kinetics of the gas phase intramolecular elimination of isobutene from 2-d1-triisobutylaluminum and the deuterium isotope effect in reactions involving cyclic transition states

The intramolecular elimination of isobutene from 2-d1-triisobutylaluminum has been studied in the gas phase for temperatures ranging between 102.4 and 184.6°C. The reaction is apparently homogeneous and obeys the first order rate law, yielding the following Arrhenius relationship: Excess ethylene was added to the starting material in order to avoid complications from the backreaction. The cyclic 4-center nature of the transition state proposed earlier has been unequivocally demonstrated by deuterium labelling. Mass-spectral analyses show that the isobutene formed contains no deuterium. The hydrolyses products of the mixed trialkylaluminum formed during the reaction consist of monodeuteroethane and 2-d1-isobutane. The observed negative entropy of activation of ∼12 cal/°-mole agrees with prediction and implies a reasonably tight transition state structure. Combined with the corresponding data for the non deuterized Al(i-bu)3 reported earlier, these data result in a primary kinetic deuterium isotope effect of kH/kD = 1.3 × 100.6/θ corresponding to a ratio of the isotopic rate constants of 3.7 at 25°C. This result is in excellent agreement with a predicted value of 1.4 × 100.7/θ and it is in line with literature data on similar reactions involving cyclic transition state complexes.
Stimulation of ATP synthesis in hypothermically perfused dog kidneys by adenosine and PO4.

Abstract During continuous hypothermic perfusion of dog kidneys there occurs a gradual decrease in ATP from about 1.4 to 0.6 μmol/g wet wt after 5 days of preservation. The loss of ATP can be prevented by including both adenosine (10 m M ) and PO 4 (25 m M ) in the perfusate. Under these conditions kidney cortex ATP levels were more than double control values — 3.5 μmol/g wet wt. Both adenosine and PO 4 were necessary since omission of one substance resulted in no net synthesis of ATP. Furthermore, these high levels of ATP were obtained only if adequate concentrations of adenosine were maintained during perfusion. Following 3 days of perfusion the adenosine level in the perfusate decreased to about 1 m M and under this condition ATP levels were low. Adenosine levels were maintained in the perfusate by two methods: (1) addition of fresh perfusate or (2) pretreatment of the kidney with the adenosine deaminase inhibitor—deoxycoformycin. The increased levels of ATP appear directly related to the availability of nucleotide precursors and the presence of inhibitors of the enzymes involved in the catabolism of nucleotides and nucleosides (PO 4 and deoxycoformycin). Mitochondrial activity was similar in kidneys with high or low ATP levels following 5 days of preservation.
Vowel and consonant contributions to vocal tract shape

The purpose of this study was to develop a method by which a vowel-consonant-vowel (VCV) utterance based on x-ray microbeam articulatory data could be separated into a vowel-to-vowel transition and a consonant superposition function. The result is a model that represents a vowel sequence as a time-dependent perturbation of the neutral vocal tract shape governed by coefficients of canonical deformation patterns. Consonants were modeled as superposition functions that can force specific portions of the vocal tract shape to be constricted or expanded, over a specific time course. The three VCVs [əpɑ], [ətɑ], and [əkɑ], produced by one female speaker, were analyzed and reconstructed with the developed model. They were shown to be reasonable approximations of the original VCVs, as assessed qualitatively by visual inspection and quantitatively by calculating rms error and correlation coefficients. This establishes a method for future modeling of other speech material.
Some New Measures of Profile Dissimilarity

Four new measures of multidimensional profile dissimilarity are proposed that are (1) either sym metric or asymmetric and (2) either conditional or unconditional on profile shape. The four similarity indices are based on alternative normalizations of the regular distance (D) statistic of Cronbach and Gleser (1953), all taking values between 0 and 1. Methods of calculation and interpretations of the indices are demonstrated and discussed, and sev eral generalizations are suggested.
A new genus and two new species of hypoaspidine mites (Acari: Laelapidae) associated with old world carpenter bees of the tribe xylocopini (Hymenoptera: Apidae: Xylocopa)

Abstract A new genus of carpenter bee-associated laelapid mites based on Hypoaspis greeni Oudemans, 1902 is recognized and diagnosed, and two new species of the genus are described from India, Sri Lanka and Sumatra (Indonesia).
Mechanism of the attenuated peak heart rate response to exercise after orthotopic cardiac transplantation.

Abstract The mechanism responsible for attenuation of the peak heart rate response to exercise in patients after cardiac transplantation was studied. Because the donor heart is believed to be surgically denervated, the peak heart rate response to exercise is dependent primarily on 1) an increase in the circulating levels of the catecholamines norepinephrine and epinephrine at peak exercise, and 2) the end-organ responsiveness of the sinoatrial (SA) node to beta-adrenergic stimulation. To assess the former mechanism, the levels of plasma nonepinephrine and epinephrine were measured at rest and at peak exercise on a cycle ergometer in 23 transplant recipients an average of 7 ± 1 months after transplantation and in 23 normal subjects matched for age. To assess the latter mechanism, the heart rate response to a graded infusion of isoproterenol was determined in six normal subjects with and without atropine pretreatment and in eight transplant recipients. In transplant recipients, both the absolute plasma levels of nonepinephrine and epinephrine at peak exercise and the increments from baseline to peak exercise were comparable with or greater than those in normal subjects. In transplant recipients, the isoproterenol dose that increased heart rate by 25 beats/min over baseline was not different from that in atropine-treated normal subjects (normal subjects 9 ± 2 ng/kg per min; transplant recipients 11 ± 1 ng/kg per min; p = NS). These data show that after cardiac transplantation, there is a normal or slight elevation of circulating catecholamines at peak exercise, and that the responsiveness of the SA node to beta-adrenergic stimulation is normal. Thus, the most likely explanation for the attenuated peak heart rate response to exercise after cardiac transplantation is lack of direct efferent innervation of the SA node.
Amalgamation of the wright and guild color‐mixture data

The mixture data for the CIE 1931 standard observer were created by amalgamating two separate sets of mixture data provided by Wright and Guild. Both sets of data were expressed in terms of the NPL system and amalgamated. It is possible to express all three sets of data in terms of Wright's system and show in terms of that system that the CIE data represent an acceptable amalgamation of the Wright and Guild data. This avoids the use of a third system for amalgamating the two sets of data. The properties of the new set of data can be defined by giving the trichromatic coefficients (chromaticity coordinates) of the spectral colors and the luminosity coefficients of the three primaries. This new amalgamated set of data can be used in connection with the V(λ) curve to derive the standard 1931 XYZ diagram and the set of x, ȳ, and z values for use in photometry and colorimetry.
Item-wording and the dimensionality of the Rosenberg Self-Esteem Scale: do they matter?

Some researchers contend that the Rosenberg Self-Esteem Scale taps two dimensions of self-image, whereas others argue that the two dimensions (positive and negative) are merely an artifact of item wording. To directly test these competing views, we had 741 ethnically diverse university undergraduates take one of three versions of the 10-item Rosenberg Scale: the original version comprised of five positively worded and five negatively worded items, or one of two alternative versions comprised of 10 positively worded or 10 negatively worded items. Analyses indicated that the original version fit a two-factor model, whereas the reworded versions generally fit a one-factor model. All three versions had high validity for different ethnic groups, but the revised-positive version had less overlap with a measure of depression, and both revised versions had less overlap with a measure of self-deception.
The equation of state of CaSiO3 perovskite to 108 GPa at 300 K

Abstract Pressure–volume measurements have been performed for CaSiO3 perovskite to 108 GPa at 300 K using NaCl and argon pressure-transmitting media, and energy dispersive X-ray diffraction (EDXD) in a diamond-anvil cell (DAC). By determining a parameter that is the product of the elastic anisotropy, S, and the uniaxial stress component, t, for each data point, we define the stress condition of the sample. For different points at the same pressure in a temperature-quenched sample, the St value can differ by as much as a factor of 5, indicating heterogeneity in the stress condition. This may be responsible for the large scatter of earlier P–V measurements in the DAC which in general used a large diameter X-ray beam. Also, the St value provides insight into the elastic anisotropy, S, of CaSiO3 perovskite and platinum. The sign of S (positive) for CaSiO3 perovskite agrees with first principles calculations but the magnitude may be inconsistent. A new compression curve at 300 K was obtained for CaSiO3 perovskite by using those data points which represent the most nearly hydrostatic conditions. It is observed that the data points with high St values yield larger volumes than the points with small St values at a given pressure. By selecting the data points having low St values (St≤0.005), combining with lower pressure large volume press (LVP) measurements and fitting to third order Birch–Murnaghan equation of state (EOS), we find that CaSiO3 perovskite is more compressible (V0=45.58±0.05 A3, KT0=236±4 GPa, and KT0′=3.9±0.2 GPa) than suggested by previous studies. The density and bulk modulus of CaSiO3 perovskite at lower mantle pressures and 300 K are 1–3% greater and 5–15% smaller, respectively, than found in previous studies. This study demonstrates that defining the stress state of the sample is crucial to obtain an accurate 300 K compression curve for unquenchable high-pressure phases.
Ellipsometry and broken time-reversal symmetry in the high-temperature superconductors.

We discuss ellipsometric experiments seeking evidence of broken time-reversal symmetry in the high-temperature copper oxide superconductors. We use both a generalized symmetry analysis, and a magnetoelectric model suggested by Dzyaloshinskii, to argue that the hypothesis that best fits the various experimental results is the [ital scrPscrT]-invariance hypothesis---which assumes broken [ital scrT] symmetry in each plane, and antiferromagnetic (alternating) order of the broken symmetry in the [ital c] direction. We suggest two experimental tests of the [ital scrPscrT]-invariant model; one of these is sufficient to rule out any other broken-symmetry state and so has the potential to be extremely useful.