cssi/SciSciGPT-SciSciNet huggingface dataset:
Sodium Benzoate for Treatment of Hepatic Encephalopathy

Hepatic encephalopathy (HE) is a serious but usually reversible neuropsychiatric complication of cirrhosis, inborn errors of metabolism involving disorders of the urea cycle, and noncirrhotic portosystemic shunting that most commonly arises from a transjugular intrahepatic portosystemic shunting procedure. Symptoms can include alterations in cognitive function, neuromuscular activity, and consciousness, as well as sleep disorders and mood changes. HE is associated with significant morbidity and mortality and, if not properly treated, will lead to increased hospital admissions and healthcare costs. Although the standard therapies of lactulose and rifaximin (Xifaxan, Salix) are effective for most patients, these drugs may be associated with significant adverse effects and expense and, in some patients, inadequate therapeutic response. A need for adjunctive therapies exists. Drugs that target serum and tissue ammonia metabolism and elimination may be important adjuncts to drugs that reduce ammonia production and absorption from the gastrointestinal tract for patients with severe or persistent overt symptoms of HE. Sodium benzoate is an inexpensive adjunctive agent that can be used in addition to lactulose and rifaximin and may provide an option for some select patients with refractory HE who have failed to respond to standard therapies or who cannot afford them. Although sodium benzoate does not share the same adverse effect profiles of standard therapies for HE, its efficacy has not been well established. Given the significant dose-dependent sodium content of this therapy, it may not be appropriate for patients with significant fluid retention or kidney dysfunction.
Perspective: Treating electron over-delocalization with the DFT+U method

Many people in the materials science and solid-state community are familiar with the acronym “DFT+U.” For those less familiar, this technique uses ideas from model Hamiltonians that permit the description of both metals and insulators to address problems of electron over-delocalization in practical implementations of density functional theory (DFT). Exchange-correlation functionals in DFT are often described as belonging to a hierarchical “Jacob’s ladder” of increasing accuracy in moving from local to non-local descriptions of exchange and correlation. DFT+U is not on this “ladder” but rather acts as an “elevator” because it systematically tunes relative energetics, typically on a localized subshell (e.g., d or f electrons), regardless of the underlying functional employed. However, this tuning is based on a metric of the local electron density of the subshells being addressed, thus necessitating physical or chemical or intuition about the system of interest. I will provide a brief overview of the history of how DFT+U came to be starting from the origin of the Hubbard and Anderson model Hamiltonians. This history lesson is necessary because it permits us to make the connections between the “Hubbard U” and fundamental outstanding challenges in electronic structure theory, and it helps to explain why this method is so widely applied to transition-metal oxides and organometallic complexes alike.
Ethics in Psychology and the Mental Health Professions: Standards and Cases

On being an ethical psychologist -- Making ethical decisions -- Enforcement of ethical conduct -- Knowing thyself: competence and credentials -- Psychotherapy part I. Ethical obligations of psychotherapists -- Pyschotherapy part II. Techniques and controversies -- The mental health business: money and manage care -- Privacy, confidentiality, and record keeping -- Psychological assessment: testing tribulations -- Multiple-role relationships I. Boundaries, risks and doing business -- Multiple-role relationships II. Close encounters -- Multiple-role relationships III. Attraction, romance, and sexual intimacies -- Relationships with colleagues, supervisees, and employees -- Marketing professional services -- The public face of mental health professionals -- Ethical dilemmas in academic settings -- Mental health practitioners in the legal system: tort and retort -- Challenging work settings: juggling porcupines -- Scholarly publication and the responsible conduct of research -- Appendix A. American Psychological Association's Ethical principles of psychologists and code of conduct -- Appendix B. Canadian Psychological Association: Canadian code of ethics for psychologists -- Appendix C. American Counseling Association: code of ethics -- Appendix D. National Association of Social Workers: code of ethics -- Appendix E. American Association of Marriage and Family Therapy: code of ethics -- Appendix F. American Psychiatric Association: The principles of medical ethics with annotations especially applicable to psychiatry.
The impact of lignin source on its self-assembly in solution

Recently, there has been a growing interest in developing value added uses for lignin, including the utilization of lignins as a precursor for carbon materials. Proper understanding of the association behavior of lignins during solution processing provides important structural information that is needed to rationally optimize the use of lignins in industry in a range of value added applications. In these experiments, we follow the assembly of lignin molecules from a variety of sources in dimethyl sulfoxide, a good solvent for lignins, using small angle neutron scattering. In order to mimic industrial processing conditions, concentrations of lignins were kept above the overlap concentration. At small length scales, short lignin segments with ∼4–10 monolignol units associate to form rigid rod-like/cylindrical building blocks, where the number of repeat units in a cylindrical segment decreases with increasing lignin concentration. These cylindrical building blocks associate to form aggregates with low cross-linking densities and a random coil or network like structures from highly branched lignin structures. The degree of branching of the base lignin molecule, which varies with source, plays a crucial role in determining their association behavior. The overall sizes of the aggregates decrease with increasing concentration at low cross-linking densities, whereas the opposite trend is observed for highly branched lignins.
CORRELATED MORPHOLOGICAL AND PHYSIOLOGICAL STUDIES ON ISOLATED SINGLE MUSCLE FIBERS II. The Properties of the Crayfish Transverse Tubular System: Localization of the Sites of Reversible Swelling

Living muscle fibers of crayfish become dark during efflux of Cl(-). This change in appearance is correlated with occurrence of vacuolation in the fixed fibers. The vacuoles begin at and are mainly confined to the terminals of the transverse tubular system (TTS) which are in diadic contact with the sarcoplasmic reticulum (SR). In electron micrographs swellings more than 1 micro in diameter may be seen connected to the sarcolemma or sarcolemmal invaginations by relatively unswollen tubules about 300-500 A wide. Darkening of the living fibers can be reversed by causing an influx of Cl(-). Vacuoles are then absent in the fixed preparations. These findings accord with the conclusion that the membrane of the TTS is anion permselective. Localization of the selectivity to the membrane of the terminals of the TTS strengthens the hypothesis that a channeling of current flow is responsible for initiation of excitation-contraction coupling. During the swelling, and upon its reversal, the area of the membrane of the terminals must change reversibly by about two to four orders of magnitude. The absence of changes in the dimensions of the unit membrane indicates that the expansion of the membrane and its subsequent shrinkage involve reversible incorporation of cytoplasmic material into the membrane phase.
Proteolysis and Lipolysis of Goat Milk Cheese

Abstract Numerous varieties of goat milk cheeses are produced worldwide. Maturation or ripening of goat and other species milk cheeses is governed by interplay of many different factors. Proteolysis and lipolysis are two major biochemical processes in the multifaceted phenomenon of cheese aging, which involves a variety of chemical, physical, and microbiological changes under controlled environmental conditions. Proteolysis of cheeses in general is influenced by several factors including plasmin, chymosin, protease from starter and nonstarter bacteria, pH and moisture levels of the curds, storage temperature and time, salt content, salt-to-moisture ratio, and humidity. Primary factors affecting lipolysis in cheeses are fatty acid composition, lipolytic enzymes, lipolytic microorganisms, moisture, temperature, storage time, oxygen, and surface area, etc. Several analytical techniques have been used to measure proteolysis of goat and (or) cow milk cheeses during ripening, such as solubility of peptides and amino acids in various solvents or precipitants, liberation of reactive functional groups, various forms of chromatography, and different forms of electrophoresis. Lipolysis of goat milk cheeses has been estimated by acid degree value (ADV), acid value, and free fatty acid concentration, while lipid oxidation of dairy goat products can be determined by peroxide value, thiobarbuturic acid value (TBA). Recent reports have shown that goat cheeses had greater rates of protein degradation than cow counterparts, and that aging time and temperature synergistically elevated most of proteolytic and lipolytic indices in goat cheeses. This paper will further discuss proteolytic and lipolytic characteristics of goat milk cheeses.
Dietary intake of whole and refined grain breakfast cereals and weight gain in men.

Research Methods and Procedures: We examined 17,881 U.S. male physicians 40 to 84 years of age in 1982 who were free of cardiovascular disease, diabetes mellitus, and cancer at baseline and reported measures of breakfast cereal intake, weight, and height. Results: Over 8 and 13 years of follow-up, respectively, men who consumed breakfast cereal, regardless of type, consistently weighed less than those who consumed breakfast cereals less often (p value for trend 0.01). Whole and refined grain breakfast cereal intake was inversely associated with body weight gain over 8 years, after adjustment for age, smoking, baseline BMI, alcohol intake, physical activity, hypertension, high cholesterol, and use of multivitamins. Compared with men who rarely or never consumed breakfast cereals, those who consumed 1 serving/d of breakfast cereals were 22% and 12% less likely to become overweight during follow-up periods of 8 and 13 years (relative risk, 0.78 and 0.88; 95% confidence interval, 0.67 to 0.91 and 0.76 to 1.00, respectively). Discussion: BMI and weight gain were inversely associated with intake of breakfast cereals, independently of other risk factors.
The function of the mating plug in the chalcedon checkerspot butterfly

After mating, males of many species of butterflies seal the female's copulatory opening with a ‘mating plug’. We examined the proximate function of this mating plug in the chalcedon checkerspot butterfly, Euphydryas chalcedona (Lepidoptera: Nymphalidae). Using interactions between free-flying males and six groups of treated females, we assessed the role of the mating plug in (1) physically preventing copulation, (2) signalling that the female has mated, and (3) inducing female mate-refusal behaviour. Males approached, landed and courted females in the manipulated and control groups with equal frequency in the field. Mating plugs did not reduce courtship persistence. When transplanted to virgin females, mating plugs usually prevented copulation, even though the females were still receptive. Mating plugs did not influence female behaviour. On the other hand, mated females became refractory immediately following mating and rarely copulated with males, even when their mating plugs were removed. Refractory behaviours of females acted in concert with mating plugs within one day of mating. However, the fact that the mating plug impedes copulation when females are receptive suggests that conflict may arise between females and their prior mates. Some females that would otherwise remate after digesting the first male's spermatophore may still be prevented from doing so because of the mating plug.
Novel techniques for chemical characterization in marine systems

Abstract The ability to identify and characterize chemical species in marine and freshwater systems has seen a dramatic improvement in recent years with the advent of a variety of novel chemical techniques. This special volume of papers presented at the 2002 AGU Ocean Sciences Meeting highlights some of the latest advances in chemical characterization as they are being applied to marine and freshwater systems. These techniques include both new technologies and new applications incorporating analytical chemistry and mass spectrometry advances and new biomolecular and immunological methods. This issue presents current research using two-dimensional gas chromatography; applications for enzyme-linked bioassays and biomolecular reporters; mass-spectrometry with a variety of inlet and ionization processes (AP-ESI, MALDI, MIMS, and DT-MS); as well as the combination of more traditional chromatographic, and nuclear staining techniques with mass spectrometry detection. These advances in chemical characterization strive to address molecular-level questions including the composition and bioavailability of DOM; the identification of metal–ligand complexes and metal bioavailability; preservation and cycling of proteins, and the identification of biopolymers. The identification and quantification of organic and inorganic compounds is allowing new insight into the biological and chemical interactions that influence the rates and processes controlling chemical distributions; metal speciation and metal–organic interactions; surface chemistry; and the distribution of specific compounds in complex mixtures.
Beam mode compositions on passage through a Fabry-Perot interferometer

A determination is made on the quality of a millimetre-wave beam on passage through a Fabry-Perot interferometer by decomposing the beam cross-section into modes. The modes are then added at the output plane, where each mode is weighted by a constant dependent on the Fresnel number.
A cross-cultural study of Mexican American, Black American, and White American women at a large urban university

Despite increased emphasis in recent literature on the psychology of women, there are few cross-cultural empirical studies of specific ethnic groups of women. This study examines comparatively how 279 Mexican American, black American, and white American college female freshmen in Houston, Texas, perceive themselves according to masculine, feminine, and androgynous measurements. The study investigates the perceived sex-role differences among the three groups of women according to the Bem Sex Role Inventory. While there were some significant differences among the three groups, the groups were more similar than different with regard to sex-role categories. The greatest percentage of each of the three ethnic/racial groups was androgynous. The findings suggest that social class is more influential than ethnicity/race in determining sex-role behavior of women. As people move upward in social class, they tend to be more homogeneous.
Retinoid-induced inhibition of bosinophil LTC4 production

Abstract Naturally occuring and synthetic retinoids demonstrate a marked antiinflammatory effect when employed in such disorders as acne and psoriastis. This effect may result in part from their inhibition of release of potent mediators (e.g. eicosanoids) by inflammatory cells. In this study, we examined the effect of eight retinoids (tretinoin, isotretinoin, retinol, retinal, acitretin, retinyl palmitate, etretinate, Ro 15–0778) on the release of leukotriene (LT)C4, an important lipid mediator generated by eosinophils. Tretinoin, isotretinoin, retinol, retinal, and acitretin at 10−5 M or 10−4 M concentrations inhibited LTC4 release by A23187-stimulated horse eonsinophils in vitro; 10−4 M retinyl palmitate was also inhibitory. However, 10−5 M etretinate augmented A23187-induced LTC4 release, and the arotinoid Ro 15–0778 had no effect on LTC4 production. These data suggest that selected retinoids may have potential use in the reduction of LTC4 generation by eosinophils. This inhibition could be beneficial in the theraphy of such diseases as bronchial asthma in which release of LTC4 may be involved in the inflammtory process.
Acid−Base Chemistry of a Carbenium Ion in a Zeolite under Equilibrium Conditions: Verification of a Theoretical Explanation of Carbenium Ion Stability

The 1,3-dimethylcyclopentenyl carbenium ion (C7H11+) was reproducibly prepared on zeolite HZSM-5 using a pulse-quench reactor, and then each of a number of bases was coadsorbed into the catalyst channels to either compete with the cation for protonation or to possibly react with it as a nucleophile. For seven bases with proton affinities (PA) between 142 and 212.1 kcal/mol, there was no reaction with C7H11+. Coadsorption of smaller amounts of dimethylacetamide (PA = 217 kcal/mol) also produced no reaction, but with a higher loading, a proton was transferred from the carbenium ion to the base to leave 1,3-dimethylcyclopenta-1,3-diene in the zeolite as a neutral olefin. Deprotonation was the primary reaction with coadsorption of either pyridine (PA = 222 kcal/mol) or trimethylphosphine (PA = 229.2 kcal/mol). The estimated experimental deprotonation enthalpy for C7H11+, ∼217 kcal/mol in the zeolite, is in excellent agreement with MP4/6-311G* gas-phase value of 215.6 kcal/mol. Coadsorption of either NH3 (PA =...
Homework Is a Complicated Thing

Kelly, D. (1990, January 2). There's no license to drop out. USA Today. Kohn, A. (1986). No contest: The case against competition. Boston: Houghton-Mifflin. Maehr, M. L., & Stallings, W. M. (1972). Freedom from external evaluation. Child Development, 43, 177-185. National Education Summit. (1996, March). (Available at http:// www.summit96.ibm.com) Russell, W. J. (1988). Editorial: Presidential campaigns and education policy. Educational Researcher, 17(2), 4, 12. Suarez-Orozco, M. M. (1989). Central American refugees and U.S. high schools: A psychological study of motivation and achievement. Stanford, CT: Stanford University Press. Thompson, T. (1994). Self-worth protection: Review and implications for the classroom. Educational Review, 46, 259-274. Webb, F. R., Covington, M. V., & Guthrie, S. W. (1993). Carrots and sticks: Can school policy influence student motivation? In T. M. Tomlinson (Ed.), Motivating students to learn: Overcoming barriers to high achievement (pp. 99-124). Berkeley, CA: McCutchan. Woodson, C. E. (1975). Motivational effects of two-stage testing. Unpublished manuscript, Institute of Human Learning, University of California at Berkeley.
Activity of L-Phenylalanine Ammonia-Lyase during Stratification and Germination of Sugar Pine Seeds

Summary Following a two-week lag period, during which time the majority of seed hydrationoccurred, PAL activity of sugar pine embryos increased four-fold during a 90-day stratification period at 5 °C. PAL activity of the female gametophyte tissue increased by 50 % over the same period, its level being one-third that of the embryos. Soluble protein content of the embryos did not change during stratification, while that of the female gametophytes decreased by 10 %. During germination, the embryo PAL level initially dropped to half that attained during stratification, then increased rapidly to a level on day six twice the initial, and finally decreased to about 35 % of the maximum rate of activity. PAL activity of the female gametophytes changed only slightly during germination. Soluble protein content of the embryos decreased by 60 % over 21 days germination, while soluble protein in the female gametophytes increased 2.5 times over the same period. The pattern and conditions for PAL activity during stratification and germination of sugar pine seeds suggests a temperature-sensitive balance between PAL-activation and PAL-inactivation systems.
The granulocyte macrophage colony stimulating factor (GM-CSF) regulates amyloid β (Aβ) production

Abstract One of the hallmarks of Alzheimer’s disease (AD) is the accumulation of amyloid beta (Aβ) plaques in the brain parenchyma. An inflammatory component to AD has been suggested in association with increased cytokine release. We have previously shown that CD40L stimulation of microglia induces increases in pro-inflammatory cytokines such as interleukin-1β (IL-1β), IL-6, IL-8 and GM-CSF. We have also shown that CD40L stimulation increases Aβ levels in HEK-293 cells over-expressing both the amyloid precursor protein (APP) and CD40 (HEK/APPsw/CD40). In this study, we show that GM-CSF neutralizing antibodies mitigate the CD40L-induced production of Aβ in HEK/APPsw/CD40 cells. In addition, we demonstrate that treatment of these cells with recombinant GM-CSF significantly increases Aβ levels. Furthermore, we show that shRNA silencing of the GM-CSF receptor gene significantly reduces Aβ levels to below base line in non-stimulated HEK/APPsw/CD40 cells. Analysis of cell surface proteins revealed that silencing of the GM-CSF receptor also decreases APP endocytosis (therefore reducing the availability of APP to be cleaved in the endosomes). Taken together, our results suggest that GM-CSF operates downstream of CD40/CD40L interaction and that GM-CSF modulates Aβ production by influencing APP trafficking. GM-CSF signaling may be a suitable therapeutic target against Aβ production in AD.
SU-FF-T-322: Geometric Calibration of a Dual Cone Beam CT System with Large Flat Panel Detectors

Purpose: To assess errors in a simple visual alignment of a dual large‐flat‐panel, cone‐beam‐CT (CBCT)system, and to obtain misalignment parameters that can be incorporated into image reconstruction for accurate target localization in image‐guidedradiation therapy (IGRT). Method and Materials: A dual CBCTsystem with large flat panels has been developed. Two tube‐detector sets are put in the orthogonal position on one optical bench. The designed source‐to‐detector distances (SDDs) and source‐to‐isocenter distances (SIDs) are 150 cm, and 100 cm, respectively. The detectors are 40 × 30cm 194μm‐pixel Varian Paxscan 4030CB flat panels. A ball bearing phantom was scanned with the system. The centroids of the ball bearing projections were measured on both detectors, and geometrical misalignments were calculated firstly for each tube/detector subsystem. Then misalignments between the two subsystems were determined. Results: The effects of out‐of‐plane tilt and skew on the image quality are very limited and have been ignored in our calibration. Calculated in‐plane rotations for both detectors were found to be small. Horizontal and vertical shifts off the detector center were 0.06 and 0.02 cm for subsystem I, and 0.2 and 0.02 cm for subsystem II, respectively. Calculated SDDs and SIDs differed from designed values by 0.5 and 0.2 cm for subsystem I, and 0.2 and 0.5 cm for subsystem II. The vertical shift between the two subsystems was 0.12 cm, and the angle between them was 87.6 degrees. Conclusion: The measurements show misalignments that are sufficient to warrant further mechanical adjustment and/or modeling of misalignment within image reconstruction. Notably the more substantial misalignments include those between the two subsystems. Conflict of Interest: This work is supported in part by Varian Medical Systems and Carestream Health Inc..
Cloning of Plasmodium falciparum by single-cell sorting

Malaria parasite cloning is traditionally carried out mainly by using the limiting dilution method, which is laborious, imprecise, and unable to distinguish multiply-infected RBCs. In this study, we used a parasite engineered to express green fluorescent protein (GFP) to evaluate a single-cell sorting method for rapidly cloning Plasmodium falciparum. By dividing a two-dimensional scattergram from a cell sorter into 17 gates, we determined the parameters for isolating singly-infected erythrocytes and sorted them into individual cultures. Pre-gating of the engineered parasites for GFP allowed the isolation of almost 100% GFP-positive clones. Compared with the limiting dilution method, the number of parasite clones obtained by single-cell sorting was much higher. Molecular analyses showed that parasite isolates obtained by single-cell sorting were highly homogenous. This highly efficient single-cell sorting method should prove very useful for cloning both P. falciparum laboratory populations from genetic manipulation experiments and clinical samples.
Inducible Costimulator Expression Regulates the Magnitude of Th2-Mediated Airway Inflammation by Regulating the Number of Th2 Cells

Background Inducible Costimulator (ICOS) is an important regulator of Th2 lymphocyte function and a potential immunotherapeutic target for allergy and asthma. A SNP in the ICOS 5′ promoter in humans is associated with increased atopy and serum IgE in a founder population and increased ICOS surface expression and Th2 cytokine production from peripheral blood mononuclear cells. However, it is unknown if increased ICOS expression contributes to disease progression or is a result of disease pathology. Methodology/Principal Findings We developed a mouse model in which ICOS surface expression levels are genetically predetermined to test our hypothesis that genetic regulation of ICOS expression controls the severity of Th2 responses in vivo. Using ICOS+/+ and ICOS+/− mice in a Th2 model of airway inflammation, we found that T cells from the ICOS+/− mice had reduced ICOS expression and decreased Th2-mediated inflammation in vivo. Although the activation status of the T cells did not differ, T cells isolated from the lungs and draining lymph nodes of ICOS+/− mice at the peak of inflammation produced less Th2 cytokines upon stimulation ex vivo. Using 4get mice, which express GFP upon IL-4 transcription, we determined that the decreased Th2 cytokines in ICOS+/− is due to reduced percentage of Th2 cells and not a defect in their ability to produce IL-4. Conclusion These data suggest that in both mice and humans, the level of ICOS surface expression regulates the magnitude of the in vivo Th2 response, perhaps by influencing Th2 differentiation.
Stage D1 prostate cancer. A nonrandomized comparison of conservative treatment options versus radical prostatectomy.

Background. Untreated Stage D1 prostate cancer is associated with a high progression rate. Various treatment modalities involving monotherapy alone have been associated with dismal results. In this retrospective study, the impact of combination therapy, local (surgery or radiation) and systemic (hormonal), compared with that of monotherapy on disease outcome was evaluated. Methods. The authors reviewed 631 patients who underwent pelvic lymphadenectomy for Stage D1 prostate cancer: 251 had radical prostatectomies and orchiectomies, 78 had radical prostatectomies alone, 97 received local irradiation and underwent orchiectomies, and 60 had orchiectomies alone
Intraocular hemorrhage causes retinal vascular dysfunction via plasma kallikrein.

Purpose Retinal hemorrhages occur in a variety of sight-threatening conditions including ocular trauma, high altitude retinopathy, and chronic diseases such as diabetic and hypertensive retinopathies. The goal of this study is to investigate the effects of blood in the vitreous on retinal vascular function in rats. Methods Intravitreal injections of autologous blood, plasma kallikrein (PK), bradykinin, and collagenase were performed in Sprague-Dawley and Long-Evans rats. Retinal vascular permeability was measured using vitreous fluorophotometry and Evans blue dye permeation. Leukostasis was measured by fluorescein isothiocyanate-coupled concanavalin A lectin and acridine orange labeling. Retinal hemorrhage was examined on retinal flatmounts. Primary cultures of bovine retinal pericytes were cultured in the presence of 25 nM PK for 24 hours. The pericyte-conditioned medium was collected and the collagen proteome was analyzed by tandem mass spectrometry. Results Intravitreal injection of autologous blood induced retinal vascular permeability and retinal leukostasis, and these responses were ameliorated by PK inhibition. Intravitreal injections of exogenous PK induced retinal vascular permeability, leukostasis, and retinal hemorrhage. Proteomic analyses showed that PK increased collagen degradation in pericyte-conditioned medium and purified type IV collagen. Intravitreal injection of collagenase mimicked PK's effect on retinal hemorrhage. Conclusions Intraocular hemorrhage increases retinal vascular permeability and leukostasis, and these responses are mediated, in part, via PK. Intravitreal injections of either PK or collagenase, but not bradykinin, induce retinal hemorrhage in rats. PK exerts collagenase-like activity that may contribute to blood-retinal barrier dysfunction.
Information Book Read-Alouds as Models for Second-Grade Authors

This article discusses the instructional practice of supporting second graders' information book writing with focused read-alouds that include discussions of information book genre elements, features, and organizational structure. The authors present specific examples of instruction and discuss the resulting information book compositions by second-grade authors that demonstrate for teachers how information book read-alouds can support young writers' genre knowledge development.
Reappraisal of a 2200 Ma-old paleosol near Waterval Onder, South Africa

Abstract A fossil soil (paleosol) about 2200 Ma-old in a deep roadcut between the towns of Waterval Boven and Waterval Onder (Transvaal), here called the Waterval Onder clay paleosol, was formerly reported to have formed on the Hekpoort Basalt. It is here thought to have developed on a thick (formerly at least 5.5 m), upward-fining and thinning sequence of sandstone, siltstone and shale derived from pre-existing soils on Hekpoort Basalt, within the basal portion of the fluvial Dwaal Heuvel Formation. In contrast to paleosols developed on Hekpoort Basalt, the Waterval Onder clay paleosol is little deformed, lacks corestones, and shows compositional variation and berthierine-rich laminae interpreted as relict bedding. The paleosol has a ridge and swale topography (linear or wavy gilgai) and a subsurface structure (mukkara) typical of modern Vertisols. Since there is considerable relict bedding, it probably formed over a short period of time (less than 7000 years) and was not ‘self plowing’ to the extent seen in modern Vertisols. Clastic dikes filled with sandstone from the overlying rocks, are evidence that the profile was periodically dry to depths of at least 2 m. More drab colored rocks below that may represent the level of permanent water table. Iron and manganese stain of layers and claystone granules within the surface horizon of the profile have some characteristics of modern rock varnish, and could be taken as evidence for life in the soil. The high ratio of ferric to ferrous iron near the surface of the paleosol, together with evidence from clastic dikes that this horizon was not waterlogged, is an indication of an oxidizing atmosphere, although probably one in which oxygen was much less abundant than it is today. The very low amounts of acid titratable bases in the shaly parent material of this paleosol and surficial loss of these bases within the paleosol, appear to have been produced by decarbonation reactions comparable to those found today in soils of vascular land plants. A likely source of weathering acid during the Precambrian is an elevated abundance of atmospheric carbon dioxide. Considering these likely atmospheric differences, together with the distribution of comparable modern Vertisols and other geological evidence, the climate under which this soil formed was probably semiarid to subhumid, seasonally dry and temperate.
TIME SERIES INTERVENTION ANALYSIS WITH APPLICATION TO MULTI-UNIT SYSTEM MAINTENANCE MANAGEMENT

Maintenance management is important in order for complex systems to continue operation with minimal interruption. A primary concern of maintenance management is the failure pattern exhibited by increasing failure rate (IFR) systems. In the existent literature, a common assumption about component behavior is that after replacement the new components work "as good as new". In this study, we relax this assumption and employ intervention analysis based on time series formulation to study the failure behavior of the system under preventive/predictive maintenance policies. We explicitly consider different preventive maintenance and replacement policies, the aging characteristics of the units as well as other operational issues. The proposed methodology provides the basis for a new approach to the vexing problem of the realistic characterization of IFR systems in the presence of maintenance intervention. The model is verified using data collected from a real life system and the parameter estimation is carried out using the refined instrumental variables method.
Purification and properties of malonyl-coenzyme A decarboxylase, a regulatory enzyme from the uropygial gland of goose.

Malonyl-coenzyme A (CoA) decarboxylase (EC 4.1.1.9) was, for the first time, purified in about 33% yield from the 100,000g supernatant of the uropygial gland of the goose by means of ammonium sulfate precipitation, Sepharose 4B gel filtration, QAE-Sephadex, and carboxymethyl (CM)-Sephadex ion exchange chromatography. This enzyme constituted about 1% of the total soluble proteins of this gland, and the purified enzyme showed a specific activity of 50–80 μmol/min/mg of protein. Sedimentation velocity (7.3 S), sedimentation equilibrium, polyacrylamide disc gel electrophoresis, sodium dodecyl sulfate polyacrylamide electrophoresis, Ouchterlony double diffusion, and immunoelectrophoresis with rabbit antiserum showed that the enzyme preparation was pure. Sedimentation equilibrium experiments showed that the molecular weight of the purified enzyme was about 186,000, and sodium dodecyl sulfate electrophoresis showed only one band with a molecular weight of 47,000. Thus, malonyl-CoA decarboxylase is a tetramer of apparently identical subunits. The amino acid composition of the enzyme is reported. Dissociation of the enzyme occurred during polyacrylamide disc gel electrophoresis, but both forms of the enzyme were enzymatically active. The pH optimum of the enzyme was at about 9.5, and from the typical Michaelis-Menten kinetic data Km and V were calculated to be 0.1 mm and 85 μmol/min/mg, respectively. The decarboxylase showed a high degree of specificity for malonyl-CoA; methylmalonyl-CoA was decarboxylated at <7% of the rate at which malonyl-CoA was decarboxylated and malonic acid was not decarboxylated. No metal ion participation in decarboxylation could be detected by the addition of chelators and/or metal ions. Neither avidin alone nor in combination with biotin affected the decarboxylase activity, suggesting that biotin is not involved in the decarboxylation. Thiol-directed reagents such as p-hydroxymercuribenzoate, bromopyruvic acid, and N-ethylmaleimide severely inhibited the enzyme, whereas similar brief treatment of the enzyme with iodoacetamide showed no inhibition. MethylmalonylCoA and acetyl-CoA inhibited malonyl-CoA decarboxylase. The probable role of this enzyme in the regulation of lipid metabolism, especially branched fatty acid synthesis, is discussed.
When warring groups meet: The use of a group approach in police ? Black community relations

A sensitivity exercise with a combined Tavistock and T-group approach was led by mental health professionals for black city residents and the local police force. Many of the usual group dynamics were observed, including greater understanding of each other by most participants and the lessening of stereotypes. But powerful and militant factions in and out of the exercise used it to confirm a much-wanted temporary cease-fire rather than to bring about an end to their “war”. The theoretically-derived focus on boundary maintenance proved impossible to sustain in the group exercise, which could not be walled-off from the reality of a socially explosive local situation. This reality negated the attempt to bring about peaceful change, the unspoken agenda of the professionals and most of the others involved in the program. The exercise demonstrated again the need for a firm contract and for mental health professionals to be clear about their roles and motives when they serve as consultants in social conflicts situations.
GYKI 52466 inhibits AMPA/kainate and peripheral mechanical sensory activity

The selectivity of the 2,3-benzodiazepine compound, GYKI 52466, was tested on wide dynamic range (WDR) dorsal horn neurons of the rat spinal cord. Using extracellular recordings, neurons were characterized by stimulation with noxious and innocuous intensities of the receptive field. In most cells, responses to iontophoretically applied (R,S)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) or kainic acid (KA), but not N-methyl-D-aspartate (NMDA), were profoundly reduced by iontophoretic ejection of GYKI 52466. The inhibition usually lasted for 5-30 min following application of GYKI 52466. In a few neurons, responses to NMDA were also decreased by GYKI 52466. Responses to both noxious and innocuous mechanical stimulation were reduced in the presence of GYKI 52466. The results provide evidence for the selective inhibition by GYKI 52466 of AMPA/KA receptor-mediated functions and support the involvement of these receptors in spinal mechanical nociception.
THE DISTRIBUTION AND ASYMMETRY OF MAMMALIAN CELL SURFACE SACCHARIDES UTILIZING FERRITIN-CONJUGATED PLANT AGGLUTININS AS SPECIFIC SACCHARIDE STAINS

The preparation, properties, and some applications of ferritin conjugates of two plant agglutinins, concanavalin A and Ricinus communis agglutinin, are reported. These conjugates serve as specific electron-dense stains for cell- and membrane-bound saccharide residues of the α-D-mannopyranosyl and s-D-galactopyranosyl configurations, respectively, and as examples of a wide range of ferritin-plant agglutinin conjugates useful as high resolution saccharide stains. By using a technique for preparing flattened membrane specimens, it was found with a variety of mammalian cell plasma membranes (lymphocyte, lymphoma, and myeloma and normal, spontaneously and virally transformed fibroblasts) that the ferritin conjugates were localized exclusively to the exterior face of the membrane, with essentially none found on the cytoplasmic face. On the exterior face the topographical distribution of ferritin conjugates appeared to be random. The asymmetrical distribution of saccharide residues to the outer membrane face can be explained by an "assembly line" process whereby new plasma membrane is made from intracellular precursor membranes. It also suggests that the saccharide-containing components of the plasma membrane do not rotate at any appreciable rate from one membrane surface to the other.
Class G, and a unification problem

Abstract In 1958, Karl Goldberg proved the following: Theorem G . Suppose A =( a ij ) is an n × n matrix over the complex field, with the following properties: (1) a ij a ji ⩾0 for i , j =1,2,…, n , and (2) a i 1 i 2 a i 2 i 3 ⋯ a i s i i = a i 2 i 1 a i 3 i 2 ⋯ a i 1 i s for all s =1,2,…, n and i t =1,2,…, n . Then A has only real characteristic values. Definition . Let G n denote the class of n × n matrices over C , the complex field, which satisfy the Goldberg conditions (1) and (2). We investigate some properties of class G related to the following topics: Schur complements, weak sign symmetry, and inequalities due to Oppenheim for positive definite matrices, and an analogue due to Markham for tridiagonal, oscillatory matrices.
How to build an atomic bomb

Critical Assembly: A Technical History of Los Alamos During the Oppenheimer Years, 1943-1945. By Lillian Hod-deson, Paul W. Henriksen, Roger A. Meade and Catherine L. Westfall. Cambridge University Press: 1993. Pp. 509. £45, $39.95.
Metabolomics and mass isotopomer analysis as a strategy for pathway discovery: pyrrolyl and cyclopentenyl derivatives of the pro-drug of abuse, levulinate.

We recently reported that levulinate (4-ketopentanoate) is converted in the liver to 4-hydroxypentanoate, a drug of abuse, and that the formation of 4-hydroxypentanoate is stimulated by ethanol oxidation. We also identified 3 parallel β-oxidation pathways by which levulinate and 4-hydroxypentanoate are catabolized to propionyl-CoA and acetyl-CoA. We now report that levulinate forms three seven-carbon cyclical CoA esters by processes starting with the elongation of levulinyl-CoA by acetyl-CoA to 3,6-diketoheptanoyl-CoA. The latter γ-diketo CoA ester undergoes two parallel cyclization processes. One process yields a mixture of tautomers, i.e., cyclopentenyl- and cyclopentadienyl-acyl-CoAs. The second cyclization process yields a methyl-pyrrolyl-acetyl-CoA containing a nitrogen atom derived from the e-nitrogen of lysine but without carbons from lysine. The cyclic CoA esters were identified in rat livers perfused with levulinate and in livers and brains from rats gavaged with calcium levulinate ± ethanol. Lastly, 3,6-diketoheptanoyl-CoA, like 2,5-diketohexane, pyrrolates free lysine and, presumably, lysine residues from proteins. This may represent a new pathway for protein pyrrolation. The cyclic CoA esters and related pyrrolation processes may play a role in the toxic effects of 4-hydroxypentanoate.
HKMG CMOS technology qualification: The PBTI reliability challenge

Abstract We present a brief overview of Positive Bias Temperature Instability (PBTI) commonly observed in n-channel MOSFETs with SiO2/HfO2/TiN dual-layer gate stacks when stressed with positive gate voltage at elevated temperatures. We review the origin and present understanding of the characteristics of oxide traps that are responsible for the complex behavior of threshold voltage stability. We discuss the various physical mechanisms that are believed to govern the transient charging and discharging of these traps as the backbone of the models that have been proposed for PBTI degradation and recovery. Next we review the state-of-the-art in PBTI characterization and we present some of the key stress results on both the device as well the circuit level. Special emphasis is given on the open PBTI issues that need to be carefully addressed for a robust reliability methodology that accurately predicts PBTI lifetimes. Finally we mention some of the gate stack scaling effects on PBTI.
Supercritical and Liquid Solvent Effects on the Enantioselectivity of Asymmetric Cyclopropanation with Tetrakis[1-[(4-tert-butylphenyl)- sulfonyl]-(2S)-pyrrolidinecarboxylate]dirhodium(II)

The enantioselectivity of the cyclopropanation of styrene and methyl phenyldiazoacetate in the presence of a dirhodium carboxylate catalyst was found to be dependent on both the dielectric constant and the coordinating ability of the solvent. The enantiomeric excess is pressure dependent in supercritical fluoroform, changing from as low as 40% ee at pressures above 100 bar to nearly 80% ee at pressures near the critical point. The pressure dependence is caused by the changing dielectric constant of the fluoroform. Reactions in some coordinating liquid solvents had greater enantioselectivities than expected on the basis of dielectric constant alone. The crystal structure of the catalyst was obtained along with spectroscopic data in order to elucidate the causes of the solvent-dependent enantioselectivity.
Community mobility among older adults with reduced kidney function: a study of life-space

Background Life-Space Assessment captures community mobility and social participation and quantifies the distance, frequency, and independence obtained as an older adult moves through his or her environment. Reduced estimated glomerular filtration rate (eGFR) is associated with decline in activities of daily living among older adults, but less is known about the association of eGFR with restrictions in mobility. Study Design Prospective observational cohort study. Setting & Participants Community-dwelling Medicare beneficiaries from the University of Alabama at Birmingham Study of Aging who had serum creatinine measured during a baseline in-home study visit and completed at least one telephone follow-up (N = 390). Predictor eGFR ≥ 60, 45-59, and 2 . Outcome Life-space mobility trajectory. Measurements Life-space mobility was evaluated by telephone every 6 months for up to 4.5 years using the previously validated Life-Space Assessment. Scores using this tool range from 0-120 (higher scores indicate greater mobility). Results Mean age of the 390 participants was 77.6 ± 5.8 (SD) years, 41% were African American, 50.5% were women; 30.0% had eGFR of 45-59mL/min/1.73m 2 , and 20.2% had eGFR 2 . Age-, race-, and sex-adjusted mean baseline life-space mobility scores were 64.8(95% CI, 62.0-67.6), 63.8 (95% CI, 60.3-67.4), and 58.3 (95% CI, 53.8-62.7) among those with eGFR categories ≥ 60, 45-59, and 2 , respectively. Compared with those with eGFRs ≥ 60mL/min/1.73m 2 , a more rapid decline in life-space mobility was found among those with eGFRs 2 , though this did not reach statistical significance ( P =0.06); a similar effect was not seen among those with eGFRs of 45-59mL/min/1.73m 2 ( P =0.3). Limitations Urinary albumin or longitudinal measures of eGFR were not available. Conclusions eGFR 2 was associated with a trend toward a more rapid decline in life-space mobility among community-dwelling older adults. Findings should be confirmed in a larger population.
Low-temperature deep oxidation of hydrocarbons by metal oxides supported on carbonaceous materials

Abstract First row transition metal oxides supported on carbonaceous materials are shown to be effective in the low temperature deep oxidation of hexane, butane and toluene to carbon dioxide and water. The oxides of manganese, cobalt, copper and zinc were supported on several different types of carbon, out of which it was found that manganese and cobalt oxide supported on Ambersorb® 572 were most durable. In addition, Ambersorb® 563 and Ambersorb® 572 were thermally stable under the reaction conditions. Mechanistic studies in cobalt oxide/Ambersorb® 572 indicate a synergism between the metal oxide and carbonaceous material. A catalytic cycle has been described, involving a CoII/CoIII couple, and the stabilizing effect of the support on the reduced form of the metal oxide.