cssi/SciSciGPT-SciSciNet huggingface dataset:
Assessment of small-angle and angle-averaged structure factor for monitoring electrostatic colloidal interactions using multiply scattered light.

Abstract The isotropic scattering coefficients of 143-nm diameter polystyrene latex suspensions were measured using frequency-domain photon migration (FDPM) at 687 and 828 nm as a function of volume fraction (0.05–0.3) and ionic strength (1.0 to 120 mM NaCl equivalents) in order to derive the angle-integrated structure factor, 〈 S ( q )〉, and structure factor at zero wave vector, S (0). The effective surface charges of the dispersions were estimated by fitting the measured isotropic scattering coefficients at each wavelength as a function of volume fraction to the solution of the Orstein–Zernike integral equation using the hard sphere Yukawa potential model and mean spherical approximation as a closure relation. The estimates of surface charges were comparable at both wavelengths, but decreased with ionic strength. At 120 mM NaCl equivalents, the values of S (0) obtained from FDPM matched those predicted by the Percus–Yevick model, and decreased with volume fraction, consistent with prediction by the Carnahan–Starling equation.
Interaction between albumin, lecithin and cephalin.

LECITHINS and cephalins form more or less stable combinations with proteins1,2. These are believed to be the result of lipid–protein interaction3. Provided the method is applicable, information regarding the interaction may be obtained by an electrophoretic method4 used for the study of interaction between dextrans and proteins. Essentially, this method uses the Antweiler micro-Tiselius apparatus to obtain spikes, at various pH's and concentrations, of the two interacting substances and of their mixtures. Plotting the areas under the spikes against concentration enables one to determine a function of α, the specific refractive increment, and sometimes to decide as to whether the mixture of the two components has resulted in interaction between them.
Propagation of waves in optical waveguides with various dielectric and metallic claddings

A new graphic method of obtaining easily the phase constant for a propagating wave is described and illustrated by a number of solutions for an optical waveguide covered with various dielectric and metallic claddings. It contains, implicitly, solutions for surface waves.
Older women of color: a feminist exploration of the intersections of personal, familial and community life.

SUMMARY This paper examines the lives of older U.S. women of color who represent racial and ethnic heritages that have a history of unequal access to sources of economic and political power in this country. These women exemplify women with vastly different cultural traditions, but are similar in that they face discrimination as women of color. The combined impact of age, gender, and racial and ethnic background is neglected within our discussions of older women. This paper contributes to our understanding of older women of color by examining the personal, familial, and community aspects of the lives of older women of color. This exploration challenges feminist gerontologists to bring the discussion of this intersection to the center as we explore and seek to comprehend the reality of older women's lives. This scrutiny creates a space for the discussion of both the threats faced by women of color in their unique juncture as old, female, and of color as well as an illumination of the strengths manifested by...
Lactate: The Ultimate Cerebral Oxidative Energy Substrate?:

Research over the past two decades has renewed the interest in lactate, no longer as a useless end product of anaerobic glycolysis in brain (and other tissues), but as an oxidative substrate for energy metabolism. While this topic would be considered blasphemy only three decades ago, much recent evidence indicates that lactate does play a major role in aerobic energy metabolism in the brain, the heart, skeletal muscle, and possibly in any other tissue and organ. Nevertheless, this concept has challenged the old dogma and ignited a fierce debate, especially among neuroscientists, pitting the supporters of glucose as the major oxidative energy substrate against those who support lactate as a possible alternative to glucose under certain conditions. Meanwhile, researchers working on energy metabolism in skeletal muscle have taken great strides toward bridging between these two extreme positions, while avoiding the high decibels of an emotional debate. Employing their findings along with the existing old and new data on cerebral energy metabolism, it is postulated here that lactate is the only major product of cerebral (and other tissues) glycolysis, whether aerobic or anaerobic, neuronal or astrocytic, under rest or during activation. Consequently, this postulate entails that lactate is a major, if not the only, substrate for the mitochondrial tricarboxylic acid cycle. If proven true, this hypothesis could provide better understanding of the biochemistry and physiology of (cerebral) energy metabolism, while holding important implications in the field of neuroimaging. Concomitantly, it could satisfy both 'glucoseniks' and 'lactatians' in the ongoing debate.
A dual role for zinc fingers in both DNA binding and zinc sensing by the Zap1 transcriptional activator

The Zap1 transcriptional activator of Saccharomyces cerevisiae controls zinc homeostasis. Zap1 induces target gene expression in zinc-limited cells and is repressed by high zinc. One such target gene is ZAP1 itself. In this report, we examine how zinc regulates Zap1 function. First, we show that transcriptional autoregulation of Zap1 is a minor component of zinc responsiveness; most regulation of Zap1 activity occurs post-translationally. Secondly, nuclear localization of Zap1 does not change in response to zinc, suggesting that zinc regulates DNA binding and/or activation domain function. To understand how Zap1 responds to zinc, we performed a functional dissection of the protein. Zap1 contains two activation domains. DNA-binding activity is conferred by five C-terminal C2H2 zinc fingers and each finger is required for high-affinity DNA binding. The zinc-responsive domain of Zap1 also maps to the C-terminal zinc fingers. Furthermore, mutations that disrupt some of these fingers cause constitutive activity of a bifunctional Gal4 DNA-binding domain–Zap1 fusion protein. These results demonstrate a novel function of Zap1 zinc fingers in zinc sensing as well as DNA binding.
Heterogeneous freezing of ice on atmospheric aerosols containing ash, soot, and soil

[1] Nucleation of ice crystals in the atmosphere often occurs through heterogeneous freezing processes in which an atmospheric aerosol acts as the ice nuclei (IN). Depending on the ambient conditions and composition of the available IN, heterogeneous nucleation may occur through one of several freezing mechanisms, including contact and immersion. In this study, an optical microscope apparatus equipped with a cooling stage and a digital camera was used to observe the freezing events of individual droplet-IN samples. For each experiment, a particular IN was either placed in contact with the surface or immersed in the bulk of an ultra pure water droplet. Using volcanic ash as the IN, we observed that inside-out contact freezing occurred at warmer temperatures than immersion freezing. We also conducted contact freezing experiments using three representative aerosol types as the potential IN. The most effective contact freezing IN was Pahokee Peat soil with an average freezing temperature of −10.5°C, followed by volcanic ash (−11.2°C), and finally soot (−25.6°C). In addition, we have used classical nucleation theory to derive the heterogeneous nucleation rates for the IN compositions explored.
Temperature-Responsive Biocompatible Copolymers Incorporating Hyperbranched Polyglycerols for Adjustable Functionality

Temperature-triggered copolymers are proposed for a number of bio-applications but there is no ideal material platform, especially for injectable drug delivery. Options are needed for degradable biomaterials that not only respond to temperature but also easily accommodate linkage of active molecules. A first step toward realizing this goal is the design and synthesis of the novel materials reported herein. A multifunctional macromer, methacrylated hyperbranched polyglycerol (HPG-MA) with an average of one acrylate unit per copolymer, was synthesized and copolymerized with N-isopropylacrylamide (NIPAAm), hydroxyethyl methacrylate-polylactide (HEMAPLA) and acrylic acid (AAc). The potential to fully exploit the copolymers by modification of the multiple HPG hydroxyl groups will not be discussed here. Instead, this report focuses on the thermoresponsive, biocompatible, and degradation properties of the material. Poly(NIPAAm-co-HEMAPLA-co-AAc-co-HPG-MA) displayed increasing lower critical solution temperatures (LCST) as the HPG content increased over a range of macromer ratios. For the copolymer with the maximum HPG incorporation (17%), the LCST was ~30 °C. In addition, this sample showed no toxicity when human uterine fibroid cells were co-cultured with the copolymer for up to 72 h. This copolymer lost approximately 92% of its mass after 17 hours at 37 °C. Thus, the reported biomaterials offer attractive properties for the design of drug delivery systems where orthogonally triggered mechanisms of therapeutic release in relatively short time periods would be attractive.
Nanostructured polyamic acid membranes as novel electrode materials.

This paper describes a new approach for the preparation of polyamic acid (PAA) composites containing Ag and Au nanoparticles. The composite film of PAA and metal particles were obtained upon electrodeposition of a PAA solution containing gold or silver salts with subsequent thermal treatment, while imidization to polyimide is prevented. The structural characterization of the films is provided by 1H NMR and Fourier transform infrared spectroscopy (FTIR), while the presence of metallic nanoparticles within the polymeric matrix was confirmed by scanning electron microscopy (SEM), cyclic voltammetry (CV), energy-dispersive X-ray analysis (EDX), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). This approach utilizes the unique reactivity of PAA by preventing the cyclization of the reactive soluble intermediate into polyimides at low temperature to design polymer-assisted nanostructured materials. The ability to prevent the cyclization process should enable the design of a new class of elect...
Blackspot bruise dependent changes in enzyme activity and gene expression in Lemhi Russet potato.

Blackspot bruise-induced changes in enzyme activity and gene expression were examined in the bruise susceptible cultivar Lemhi. The activities of several enzymes involved with the synthesis and metabolism of phenolic intermediates were examined over the time course of blackspot bruise development in tubers. A large, transient increase (200-fold) in phenylalanine ammonia lyase (PAL) activity was observed, while other enzymes examined (chorismate mutase, tyrosine ammonia-lyase, 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase, and polyphenol oxidase) showed either modest or no activation. Maximal PAL activity was observed 48 hours after bruise induction, well after the discoloration reactions were complete. The change in PAL activity was associated with a transient increase in messenger RNA coding for PAL. In addition, messenger RNAs encoding two stress-induced genes, ubiquitin and the 70 kD heat shock protein, were transiendy induced by bruising. Physical impact also induced a marked decrease, followed by recovery, in the messenger RNA level for patatin, a primary storage protein in the tuber. These results suggest that the stress resulting in blackspot bruising elicits a wound response similar to those observed in other injuries to plant tissues.
Erythropoietin in Diabetic Macular Edema and Renal Insufficiency

Erythropoietin was administered to five anemic azotemic diabetic subjects for 1 year to assess the effect of increasing red cell mass on clinical well-being and the course of renal functional decline. None of the subjects manifested worsened hypertension or cerebrovascular or cardiovascular complications despite an increase in mean hematocrit from a baseline mean of 29.6% to a mean of 39.5%. The serum creatinine concentration after 1 year of treatment with erythropoietin was 3.7 mg/dL, which was unchanged from the baseline value of 3.5 mg/dL. Plasma viscosity remained constant as red cell mass increased. Although the viscosity of whole blood rose as the hematocrit increased, it was within the range of normal blood viscosity for an equivalent hematocrit. The favorable impact of erythropoietin treatment on three diabetic subjects who had macular edema and anemia is described. One hypothesis to explain the benefit of a raised hematocrit on both diabetic nephropathy and retinopathy is that the metabolic, hormonal, and hemodynamic components of the diabetic syndrome, in concert, produce tissue and cellular hypoxia that is ameliorated in part by the greater oxygen-transporting capacity of a raised red cell mass. The pseudohypoxia of diabetes may be implicated in the pathogenesis of diabetic neuropathy, retinopathy, muscular dysfunction, and nephropathy.
Temporal Framing in Health Advertising: The Role of Risk and Future Orientation

Abstract This research examines the effects of the temporal frame of an advertising message and individual differences in future orientation on consumer risk perceptions, persuasion, and behavioral intentions. Results from two experiments indicate that temporal framing effects are moderated by consumers' tendency to think about the distant-future consequences of their behaviors. In Study 1, results show that future orientation moderates temporal framing effects on consumers' perceived risk. Study 2 demonstrates that consumer risk perceptions can mediate this interaction effect for intentions to engage in preventive behaviors. Implications are offered for advertising theory, as well as for creators of public service advertising campaigns.
Modeling the Rate of Premature Ventricular Contractions and its Response to Lidocaine Infusion

The rate of premature ventricular contractions (PVC rate) and the dynamics of its response to the intravenous infusion of the antiarrhythmic drug lidocaine was modeled to facilitate the design of a closed-loop drug infusion system. An autoregressive moving average model structure with the lidocaine infusion rate as an exogenous input (ARMAX structure) was used. System identification experiments were performed using a canine model of myocardial infarction. The drug infusion rate was varied using a pseudorandom binary sequence (PRBS) test input to excite the system about an operating point established by an exponential infusion regimen. PVC's were detected in real time with a correlation technique. Model parameters were estimated in an offline data analysis. First-order models provided an adequate representation of the PVC rate in eight of ten runs. A second-order model was validated for two runs.
Family engagement practices in residential group care: Differences between public and private cases

This article reports on findings from a survey of residential group care programs in a southeastern state. The study documented differences in program efforts to engage families whose children are placed through public agencies, and those families who retain control over the placement of their children. Statistically significant differences were found in the areas of shared decision making, expectations of the families in relation to case planning activities, and expectations of families to continue or resume parenting responsibilities.
Theory of thin proximity-effect sandwiches. II. Effects of s -wave elastic scattering

We show that Anderson's theorem concerning s-wave elastic scattering is inapplicable to certain types of inhomogeneous superconductors. The example of a proximity-effect sandwich consisting of a thin normal N metal in perfect contact with a thick superconducting (S)metal is considered in detail. The proper treatment of s-wave elastic scattering in the N metal is developed. Previously inexplicable experimental results on tunneling into NS sandwiches are found to be understandable in terms of the theory presented.
Does the Local‐Option Sales Tax Provide Property Tax Relief? The Georgia Case

This study examines the effect of a one percent local-option sales tax (LOST) on property tax level, millage rate, and total spending level in Georgia counties. The study covers a 13-year period for 136 Georgia counties. The findings suggest that the law, which requires rollback of property taxes when the LOST is used, led to actual property tax relief as well as millage rate reduction. Regression results show that counties collecting the LOST tend to have per capita property taxes that are an average of $12 or 1.8 mills lower than counties that do not collect the tax. Whereas an extra dollar of LOST revenue provides about 28 cents in property tax relief, it leads to an increase in total spending of about 48 cents. In sum, the LOST has achieved the objectives of property tax relief, but on balance it is more an augmentation of than an effective substitute for property taxes in Georgia counties.
Presentations over HNP rings with enough invertible ideals and torsionfree cancellation over neoclassical orders

Abstract We prove a uniqueness theorem for presentations of modules over a class of hereditary noetherian prime rings that includes the hereditary orders studied in integral representation theory. The result also generalizes the elementary divisor theorem for non-commutative PIDs. A key part of the proof is an extension of a direct sum cancellation theorem of Drozd to torsionfree modules over a class of non-commutative rings that need not be module finite over their center.
Heterosocial communicative behavior and communication apprehension

This paper investigated the relationship between dating and communication apprehension. Results indicated that four of the eight dating variables differentiated between high and low communication apprehensives (i.e., conditioned anxiety, heterosocial apprehension, physical attractiveness, and heterosocial skills). In addition, discussions and recommendations were made for future research in three areas: (1) treatment programs for individuals with communicative deficits; (2) causal models examining CA and relational practices variables; and (3) the conceptualization and operationalization of heterosocial satisfaction and heterosocial quantity.
High-dose radiotherapy with or without androgen deprivation therapy for intermediate-risk prostate cancer: cancer control and toxicity outcomes.

Purpose To evaluate the impact of short-course androgen deprivation therapy (ADT) on cancer control outcomes and toxicity in intermediate-risk prostate cancer treated with dose-escalated external beam radiotherapy (high-dose radiotherapy [HDRT]). Methods and Materials Demographic, disease, and treatment characteristics of prostate cancer patients at 2 institution consortiums were charted. Of 296 men with intermediate-risk prostate cancer (defined as ≥T2b, prostate-specific antigen level >10 ng/mL, or Gleason score [GS] of 7, with none of the following: ≥T3, prostate-specific antigen level >20 ng/mL, GS ≥8, or positive nodes) treated with HDRT to a dose of 72 Gy or greater, 123 received short-course ADT and 173 did not. Univariate and multivariate analyses on biochemical failure–free survival (BFFS) (including subset analysis by disease factors) and on overall survival (OS) were performed, as were comparisons of gastrointestinal (GI) and genitourinary (GU) toxicity rates. Results For the whole group, the median dose was 75.6 Gy; the minimum follow-up was 2 years, and the median follow-up was 47.4 months. For ADT vs. no ADT, the 5-year BFFS rate was 86% vs. 79% ( p = 0.138) and the 5-year OS rate was 87% vs. 80% ( p = 0.159). On multivariate analysis, percent positive cores (PPC) ( p = 0.002) and GS ( p = 0.008) were significantly associated with BFFS, with ADT showing a trend ( p = 0.055). The impact of ADT was highest in the subsets with PPC greater than 50% ( p = 0.019), GS 4+3 ( p = 0.078), and number of risk factors greater than 1 ( p = 0.022). Only intensity-modulated radiotherapy use ( p = 0.012) and GS ( p = 0.023) reached significance for OS, and there were no significant differences in GU or GI toxicity. Conclusions Although the use of ADT with HDRT did not influence BFFS, our study suggests a benefit in patients with PPC greater than 50%, GS 4+3, or multiple risk factors. No OS benefit was shown, and ADT was not associated with additional radiotherapy-related GI or GU toxicity.
Localization of glycogen phosphorylase in specific cell types during differentiation of Dictyostelium discoideum.

Abstract The localization of glycogen phosphorylase was studied during the differentiation of prespore and prestalk cells in Dictyostelium discoideum. Ultramicrotechniques were utilized to assay the enzyme activity in cell samples as small as 0.02 μg dry wt in reaction volumes of 0.1 μl. The activity was assayed using an amplification procedure employing the enzymatic cycling of pyridine nucleotides. Glycogen phosphorylase from individual organisms was assayed during the developmental period. Early in development, activity was low but gradually increased to a maximum value at culmination. From culmination to sorocarp, enzyme activity decreased rapidly. Cell-specific assays of spores showed that phosphorylase activity increased slightly to culmination, and then decreased. Prestalk cells showed the greatest activity in the area of stalk sheath construction and elongation. Stalk cells showed a decreasing gradient of enzyme activity from the tip of the stalk to the base. Enzyme activity in the spores may be sufficient to provide glucose units for trehalose synthesis and spore coat production. The prestalk enzyme may degrade glycogen to provide glycosyl units for production of the stalk sheath and trehalose. Possible models of cell-specific biochemical events in Dictyostelium discoideum are discussed.
Atoms-in-molecules and electron localization function study of the phosphoryl bond

Calculations at the B3LYP/6-311+G(d,p)//B3LYP/6-311+G(d,p) level involving the atoms-in-molecules (AIM) and electron localization function (ELF) methods have been carried out for a variety of PO-bond-containing molecules in an effort to further characterize the phosphoryl bond. One cannot distinguish the phosphoryl bond from a conventional PO double bond by comparing bond distances. Both the bond breaking energies and delocalization indices do divide into the three classes of single, double, and phosphoryl and tend to parallel each other. On the basis of the PO bond in HPO having a reference bond order of 2.0, the phosphoryl bond has a bond order of about 1.3. Examination of localized orbitals confirm our ideas that the phosphoryl bond is highly polar as, indeed, are the other PO bonds. What sets the phosphoryl bond apart is the high degree of back-bonding that contributes to the delocalization index (and covalent bond order) and provides for its stronger-than-single-bond character and short bond distance.
A Multivariate Model for Comparison of Two Datasets and its Application to FMRI Analysis

In this work, we propose a structured approach to compare common and distinct features of two multidimensional datasets using a combination of canonical correlation analysis (CCA) and independent component analysis (ICA). We develop formulations of information theoretic criteria to determine the dimension of the subspaces for common and distinct features of the two datasets. We apply the proposed method to a simulated dataset to demonstrate that it improves the estimation of both common and distinct features when compared to performing ICA on the concatenation of two datasets. We also apply the method to compare brain activation in functional magnetic resonance imaging (fMRI) data acquired during a simulated driving experiment and observe distinctions between the driving and watching conditions revealed in relevant brain function studies.
The technocratic body: American childbirth as cultural expression

The dominant mythology of a culture is often displayed in the rituals with which it surrounds birth. In contemporary Western society, that mythology--the mythology of the technocracy--is enacted through obstetrical procedures, the rituals of hospital birth. This article explores the links between our culture's mythological technocratic model of birth and the body images, individual belief and value systems, and birth choices of forty middle-class women--32 professional women who accept the technocratic paradigm, and eight homebirthers who reject it. The conceptual separation of mother and child is fundamental to technocratic notions of parenthood, and constitutes a logical corollary of the Cartesian mind-body separation that has been fundamental to the development of both industrial society and post-industrial technocracy. The professionals' body images and lifestyles express these principles of separation, while the holistic ideology of the homebirthers stresses mind-body and parent-child integration. The conclusion considers the ideological hegemony of the technocratic paradigm as potential future-shaper.
Synthesis and Evaluation of Thioether-Based Tris-Melamines as Components of Self-Assembled Aggregates Based on the CA.M Lattice.

Two new tris-melamine derivatives, triazine-thio-M3 (5) (C3N3-2,4,6-[SCH2C6H4-3-N(CH2C6H4-4-C(CH3)3)COC6N3-2-NHC3N3(NH2)(NHCH2CH2C(CH3)3)-5-Br]3) and benzene-thio-M3 (6) (C6H3-1,3,5-[SCH2C6H4-3-N(C...
Metal ion-dependent modulation of the dynamics of a designed protein

The peptide alpha 4 is a designed four-helix bundle that contains a highly simplified hydrophobic core composed exclusively of leucine residues; its tertiary structure is therefore largely dictated by hydrophobic forces. This small protein adopts a structure with properties intermediate between those of the native and molten globule states of proteins: it is compact, globular, and has very stable helices, but its apolar side chains are mobile and not as well packed as in many natural proteins. To induce a more native-like state, two Zn(2+)-binding sites were introduced into the protein, thereby replacing some of the non-specific hydrophobic interactions with more geometrically restrictive metal-ligand interactions. In the metal-bound state, this protein has properties that approach those of native proteins. Thus, hydrophobic interactions alone are sufficient to drive polypeptide chain folding nearly to completion, but specific interactions are required for a unique structure.
Q-Learning and p-persistent CSMA based rendezvous protocol for cognitive radio networks operating with shared spectrum activity

With an increasing demand for spectrum, dynamic spectrum access (DSA) has been proposed as viable means for providing the flexibility and greater access to spectrum necessary to meet this demand. Within the DSA concept, unlicensed secondary users temporarily "borrow" or access licensed spectrum, while respecting the licensed primary user's rights to that spectrum. As key enablers for DSA, cognitive radios (CRs) are based on software-defined radios which allow them to sense, learn, and adapt to the spectrum environment. These radios can operate independently and rapidly switch channels. Thus, the initial setup and maintenance of cognitive radio networks are dependent upon the ability of CR nodes to find each other, in a process known as rendezvous, and create a link on a common channel for the exchange of data and control information. In this paper, we propose a novel rendezvous protocol, known as QLP, which is based on Q-learning and the p-persistent CSMA protocol. With the QLP protocol, CR nodes learn which channels are best for rendezvous and thus adapt their behavior to visit those channels more frequently. We demonstrate through simulation that the QLP protocol provides a rendevous capability for DSA environments with different dynamics of PU activity, while attempting to achieve the following performance goals: (1) minimize the average time-to-rendezvous, (2) maximize system throughput, (3) minimize primary user interference, and (4) minimize collisions among CR nodes.
A FACTOR ANALYSIS OF PERCEPTUAL TESTS

A factorial study of perceptual tests and reference factor tests was carried out on a population of low scholastic level (1) to obtain evidence on whether or not Thurstone's closure factors extended into the cognitive domain, and (2) to find out whether the reference tests were suitable factorial tests for the level of population used. Ten reference tests, the six parts of the ACEPE, adaptations of five tests that have loaded the closure factors in earlier studies, and two new tests designed to measure cognitive closure were included. The results indicate that the reference tests did not work well on this population. Some evidence was obtained that closure is limited to perception and does not extend into the domain of cognition.
An FTIR and XPS investigations of the effects of carbonation on the solidification/stabilization of cement based systems-Portland type V with zinc

The effects of carbonation on the solidification/stabilization (S/S) of zinc using Portland cement Type V (OPC) has been investigated by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). The FTIR results indicate that carbon dioxide reacts with the metal-bonded and hydrogen-bonded hydroxides [CaZn[sub 2](OH)[sub 6][center dot]2H[sub 2]O] generally present in zinc-doped Portland cement (Zn-OPC) samples. XPS examinations of the carbonated products of the undoped and doped (Zn-OPC) samples indicate that the resulting silica phases have chemical states different from standard silica gel. Both FTIR and XPS results suggest that carbonation promotes polymerization of the SiO[sub 4] units present in OPC matrix. The chemical states of the surface components obtained by XPS analysis are discussed in the light of polymerization of the silicates.
Clinical Risk Assessment: Identifying Patients at High Risk for Heart Failure

Care requirements differ for individual patients in the heart failure continuum of care. Few tools exist that enable the bedside nurse to assess the cardiac surgical patient effectively. A quality improvement project was conducted at a level I trauma center in the mid-Atlantic United States to identify perioperative heart failure patients who do poorly after cardiac surgery. The surgical patient who is at high risk for adverse events after coronary artery bypass graft surgery can be identified by clustering 11 characteristics. Of 1,971 patients studied, 294 had adverse outcomes. Data indicated that any cluster of the characteristics was intensified when emergency status was added.
Mechanisms of Water Oxidation Catalyzed by Ruthenium Diimine Complexes

18O-isotope-labeling studies have led to the conclusion that there exist two major pathways for water oxidation catalyzed by dimeric ruthenium ions of the general type cis,cis-[L2RuIII(OH2)]2O4+. We have proposed that both pathways involve concerted addition of H and OH fragments derived from H2O to the complexes in their four-electron-oxidized states, i.e., [L2RuV(O)]2O4+, ultimately generating bound peroxy intermediates that decay with the evolution of O2. The pathways differ primarily in the site of addition of the OH fragment, which is either a ruthenyl O atom or a bipyridine ligand. In the former case, water addition is thought to give rise to a critical intermediate whose structure is L2RuIV(OH)ORuIV(OOH)L24+; the structures of intermediates involved in the other pathway are less well defined but may involve bipyridine OH adducts of the type L2RuV(O)ORuIV(OH)(L•OH)L4+, which could react further to generate unstable dioxetanes or similar endoperoxides. Published experimental and theoretical support f...
Differential survivorship of allozyme genotypes in mosquitofish populations exposed to copper or cadmium

Laboratory stocks of mosquitofish (Gambusia affinis) were acutely exposed to copper (0.16–0.24 mg/L) or cadmium (6.7–9.5 mg/L) for 48 h using a static renewal system. Allozyme genotypes at three polymorphic loci: phosphoglucomutase‒2 (PGM‒2), glucose phosphate isomerase‒2 (GPI‒2), and isocitrate dehydrogenase‒2 (ICD‒2) were resolved using a modified starch gel (13%) electrophoretic technique. Differential survivorship of allozyme genotypes was analyzed using a Wilcoxon matched pair signed‒rank test. Copper significantly (p < 0.05) decreased the overall survivorship of fish heterozygous at the GPI‒2 locus. The frequency of the (ab) genotype was significantly higher in the dead fraction of the test populations than in the surviving fraction. The frequencies of the (aa) genotype and the (a) allele at the ICD‒2 locus were significantly higher in female fish surviving exposure to copper than in nonsurviving females. The frequencies of the (bb) genotype and the (b) allele at the GPI‒2 locus were significantly higher in fish surviving exposure to cadmium than in nonsurvivors. These results indicate that some electrophoretically detectable allozymes are more sensitive than others to the toxic effects of environmental pollutants. This suggests that the genetic structure of natural populations should be considered for use as a biological monitor of environmental pollution.
Can evolved forward transforms do better than wavelets

State-of-the-art image compression and reconstruction schemes utilize wavelets. Quantization and thresholding are commonly used to achieve additional compression, but cause permanent, irreversible information loss. This paper describes an investigation into whether evolutionary computation (EC) may be used to optimize forward (compression-only) transforms capable of matching or exceeding the compression capabilities of a selected wavelet, while reducing the aggregate error in images subsequently reconstructed by that wavelet. Transforms are independently trained and tested using three sets of images: digital photographs, fingerprints, and satellite images.
An assessment of factors influencing data obtained by the photoelastic stress freezing technique for stress fields near crack tips

Abstract Factors which influence crack tip stress field data are identified as: (1) Non-linear zone near crack tip due to crack blunting. (2) Normal stress parallel to crack surface. (3) Location of region for data retrieval. The Kolosoff-Inglis solution is used in order to assess effects of crack tip blunting. A set of stress freezing photoelastic experiments are conducted on plates containing through cracks and results are compared with the Westergaard solution in order to assess the effect of Item 2 using appropriate Item 3 locations. A data conditioning computer program is employed to yield accurate values of the stress intensity factor from photoelastic data.
The winged helix transcription factor Hfh2 is expressed in neural crest and spinal cord during mouse development.

Abstract The embryonic neural crest is a unique group of cells that gives rise to the peripheral nervous system as well as many other cell types. Most of the work describing the behavior and specification of these cells has been done in the avian system, a system amenable to experimental manipulations such as tissue grafting, cell transplantation and lineage tracing. This work has been greatly facilitated by the use of molecular markers of neural crest cells such as HNK-1 and slug, markers that are not yet available for the study of mouse neural crest. Here we demonstrate that Hfh2 ( H NF3 f orkhead h omologue 2), a member of the `winged helix' or `forkhead' transcription factor gene family, is expressed in premigratory and migrating neural crest cells in the early mouse embryo and in motorneuron and interneuron progenitors in the developing spinal cord. Using linkage analysis we have localized the Hfh2 gene to chromosome 4 at 44.91 cM from the centromere.
Physical activity and cardiovascular risk: a cross-sectional study of middle-aged premenopausal women

The relationship between self-reported physical activity and cardiovascular risk factors was evaluated in a population-based sample. The sample included 541 premenopausal women recruited for a study of the natural history of risk factor change associated with change in sex hormone status. Physical activity was assessed using the Paffenbarger Activity Questionnaire. Women were classified according to quartile of weekly energy expenditure into groups of 0-500, 501-999, 1,000-1,999, and 2,000 kcal or greater. Results showed that the more active the women, the lower their blood pressure and heart rate. More active women had lower cholesterol and triglycerides, and higher high-density lipoprotein (HDL) cholesterol. Tricep and suprailiac skinfolds, fasting insulin, and insulin/glucose levels were also lower among the more active women. When the analysis was repeated controlling for the effect of education and body mass index, the statistical test for linear trend remained significant except for the trend for heart rate, total cholesterol, and triglycerides. Women reporting activity of 1,000 kcal/week had higher high-density lipoprotein cholesterol and lower diastolic blood pressure, body mass index, skinfolds, fasting insulin, and fasting insulin/glucose ratios compared with women reporting lower levels of activity. Only those women who reported 2,000 kcal/week had significantly lower total cholesterol, triglycerides, and low-density lipoprotein cholesterol, and higher HDL2 cholesterol; women reporting less activity did not differ with regard to these lipids and lipoproteins. The study suggests that physical activity is associated with improved cardiovascular risk profiles among middle-aged women and that the beneficial effects of activity are seen at different levels for specific risk factors.
Surplus Deferred Pension Compensation for Long-Term K-12 Employees: An Empirical Analysis for the Denver Public School Retirement System and Four State Plans

This study uses a unique data set of retiree characteristics and salary histories for administrators, teachers, and non-professional employees of the Denver Public School Retirement System (DPSRS) to analyze surplus deferred compensation for DPSRS and four state K-12 defined benefit pension plans. We find sizable levels of surplus deferred compensation for each plan, with significant differences across plans, job classes, and age groups. Across plans, differences in cost of living allowances impact the expected present value of retirement benefits more than benefit table differences when controlling for each respective factor. Somewhat surprisingly, the plans in our study with the largest present value of future benefits had lower employee contribution rates. Pension wealth for reduced benefits showed larger wealth accrual at younger ages than full, unreduced benefits, and younger cohorts starting work at an earlier age received significantly higher surplus deferred compensation.
Equilibrium constants and optical spectra of 1:1 and 2:1 electron donor—acceptor complexes with overlapping bands

Abstract Equilibrium constants and molar absorptivities of the 1:1 and 2: 1 electron donor—acceptor complexes of a previously unstudied system ( p -xylene/ p -bromanil) have been determined. Since the optical spectrum of the acceptor ( p -bromanil) severely overlaps the charge-transfer spectra of the complexes, a parameterized matrix modeling method was used to resolve the experimental absorption spectra into contributions from the acceptor (A) the 1:1 complex (DA), and the 2:1 complex (D 2 A). Association constants for the bimolecular and termolecular complexes were found to be 3.696 ± 0.521 mol −1 and 1.095 ± 0.0061 mol −1 , respectively.
Toremifene Decreases Vertebral Fractures in Men Younger Than 80 Years Receiving Androgen Deprivation Therapy for Prostate Cancer

Purpose: Androgen deprivation therapy is associated with an increased fracture risk. In a recent phase III trial toremifene significantly decreased vertebral fractures in men on androgen deprivation therapy. Similar to other selective estrogen receptor modulators, toremifene was associated with an increase in venous thromboembolic events with the greatest risk in men 80 years old or older. In this post hoc analysis we evaluated the efficacy and safety of toremifene in men younger than 80 years.Materials and Methods: This analysis included 847 men younger than 80 years, of whom 430 received toremifene 80 mg by mouth daily and 417 received placebo for up to 24 months. The primary end point was new vertebral fractures. Secondary end points included fragility fractures, bone mineral density and safety.Results: Compared with placebo, toremifene decreased the relative risk of new vertebral fractures by 79.5% (95% CI 29.8–94.0, p <0.005). The new vertebral fracture incidence was 1.0% for toremifene and 4.8% for ...
Reactions of nitric oxide with a low-spin Fe(III) center ligated to a tetradentate dicarboxamide N4 ligand: parallels between heme and non-heme systems.

Reaction of excess NO with the non-heme Fe(III) complex [(bpb)Fe(py)2]ClO4 in MeCN under strictly anaerobic conditions affords the {Fe−NO}6(nitro)(nitrosyl) complex [(bpb)Fe(NO)(NO2)] (1) via metal-promoted NO disproportionation, while in a MeOH/MeCN mixture, the same reaction leads to reductive nitrosylation and generation of the {Fe−NO}7 species [(bpb)Fe(NO)] (2). Exposure of a solution of 1 in DMF to dioxygen leads to formation of the ring-nitrosylated product [(bpb-NO2)Fe(NO3)(DMF)] (3). The present system therefore exhibits all the NO reactivities reported so far with the iron−porphyrins.
Non-Transfer of Materials between Plasmodia of Different Species of Myxomycetes

Under the experimental conditions of this study no transfer of radiophosphorus occurred from one living plasmodium to another when a radioactive plasmodium ofPhysarum polycephalum and a non-radioactive plasmodium ofPhysarum gyrosum orFuligo septica were in intimate contact for 24 hours.
Social skills training for juvenile delinquents.

Abstract Twenty-seven incarcerated juvenile delinquents matched on the number of previous offenses, age, WISC-R IQ, and locus of control were assigned to a Social Skills. Discussion or Control group. Social skills training consisted of instruction, feedback, modeling, behavior rehearsal, social reinforcement and graduated homework assignments. All subjects were assessed before and after treatment on a variety of self-report, role-play and behavioral measures. Analyses of variance for difference scores indicated that the Social Skills group improved significantly more than the Discussion and Control groups, which did not differ. Appropriate interpersonal skills were learned, state anxiety was reduced, internal locus of control was increased, and significant shifts in adjustment to the institutional program were evidenced for the Social Skills group.
Presentation and Perioperative Management of Arterioportal Fistulas

• Arterioportal fistulas (APFs) are usually traumatic in origin and may result in portal hypertension and its complications. Over six years, six patients (aged 20 to 59 years) presented with APFs. Two APFs developed after percutaneous liver biopsy, but only one was complicated (hemobilia). Neither patient was treated operatively. Four APFs occurred two days to three years after gunshot wounds. Three patients presented with gastrointestinal tract hemorrhage. All patients had abdominal bruits. Two patients underwent primary repair. One patient underwent APF resection and replacement of the superior mesenteric artery with autogenous vein. Another patient underwent APF and bowel resection. Three patients survived. One patient died of liver failure. The development of an abdominal bruit in a patient with penetrating abdominal trauma suggests APF and should prompt angiography. Elective repair is recommended before complications of portal hypertension develop. (Arch Surg1987;122:563-571)
Interconvertible molecular-weight forms of the bifunctional chorismate mutase-prephenate dehydratase from Acinetobacter calcoaceticus.

Abstract Acinetobacter calcoaceticus belongs to a large phylogenetic cluster of gram-negative procaryotes that all utilize a bifunctional P-protein (chorismate mutase-prephenate dehydratase) [EC 5.4.99.5-4.2.1.51] for phenylalanine biosynthesis. These two enzyme activities from Ac. calcoaceticus were inseparable by gel-filtration or DEAE-cellulose chromatography. The molecular weight of the P-protein in the absence of effectors was 65,000. In the presence of l -tyrosine (dehydratase activator) or l -phenylalanine (inhibitor of both P-protein activities), the molecular weight increased to 122,000. Maximal activation (23-fold) of prephenate dehydratase was achieved at 0.85 m m l -tyrosine. Under these conditions, dehydratase activity exhibited a hysteretic response to increasing protein concentration. Substrate saturation curves for prephenate dehydratase were hyperbolic at l -tyrosine concentrations sufficient to give maximal activation (yielding a K m ,app of 0.52 m m for prephenate), whereas at lower l -tyrosine concentrations the curves were sigmoidal. Dehydratase activity was inhibited by l -phenylalanine, and exhibited cooperative interactions for inhibitor binding. A Hill plot yielded an n ′ value of 3.1. Double-reciprocal plots of substrate saturation data obtained in the presence of l -phenylalanine indicated cooperative interactions for prephenate in the presence of inhibitor. The n values obtained were 1.4 and 3.0 in the absence or presence of 0.3 m m l -phenyl-alanine, respectively. The hysteretic response of chorismate mutase activity to increasing enzyme concentration was less dramatic than that of prephenate dehydratase. A K m ,app for chorismate of 0.63 m m was obtained. l -Tyrosine did not affect chorismate mutase activity, but mutase activity was inhibited both by l -phenylalanine and by prephenate. Interpretations are given about the physiological significance of the overall pattern of allosteric control of the P-protein, and the relationship between this control and the effector-induced molecular-weight transitions. The properties of the P-protein in Acinetobacter are considered within the context of the ubiquity of the P-protein within the phylogenetic cluster to which this genus belongs.
Climatic controls of aboveground net primary production in semi‑arid grasslands along a latitudinal gradient portend low sensitivity to warming

Although climate models forecast warmer temperatures with a high degree of certainty, precipitation is the primary driver of aboveground net primary production (ANPP) in most grasslands. Conversely, variations in temperature seldom are related to patterns of ANPP. Thus forecasting responses to warming is a challenge, and raises the question: how sensitive will grassland ANPP be to warming? We evaluated climate and multi-year ANPP data (67 years) from eight western US grasslands arrayed along mean annual temperature (MAT; ~7–14 °C) and mean annual precipitation (MAP; ~250–500 mm) gradients. We used regression and analysis of covariance to assess relationships between ANPP and temperature, as well as precipitation (annual and growing season) to evaluate temperature sensitivity of ANPP. We also related ANPP to the standardized precipitation evaporation index (SPEI), which combines precipitation and evapotranspiration to better represent moisture available for plant growth. Regression models indicated that variation in growing season temperature was negatively related to total and graminoid ANPP, but precipitation was a stronger predictor than temperature. Growing season temperature was also a significant parameter in more complex models, but again precipitation was consistently a stronger predictor of ANPP. Surprisingly, neither annual nor growing season SPEI were as strongly related to ANPP as precipitation. We conclude that forecasted warming likely will affect ANPP in these grasslands, but that predicting temperature effects from natural climatic gradients is difficult. This is because, unlike precipitation, warming effects can be positive or negative and moderated by shifts in the C3/C4 ratios of plant communities.