cssi/SciSciGPT-SciSciNet huggingface dataset:
Isocitrate lyase from Neurospora crassa: pH dependence of catalysis and interaction with substrates and inhibitors.

The maximal velocity, V, for isocitrate cleavage by isocitrate lyase from Neurospora crassa is dependent on two dissociable groups with pKa values of 6.1 and 8.6. A dissociable group with a pKa of 8.5 on the enzyme-substrate complex affects the pKm for isocitrate. The pKi for homoisocitrate is affected in a like manner. The pH dependence of the pKi's for succinate, a product of isocitrate cleavage, and the succinate analog maleate is similar to the pH dependence of the pKm of isocitrate below pH 7.3, but is markedly different above this pH. Both the Km for isocitrate and the Ki for succinate were dependent upon Mg2+ concentration. The pKi for oxalate, an analog of glyoxylate which is also a product of isocitrate cleavage, is dependent on a group with a pKa of 6.8 on the enzyme-inhibitor complex. The pH dependence of the pKi for phosphoenolpyruvate, which binds to the succinate site, suggests that it is dependent on two dissociable groups, one on phosphoenolpyruvate and one, by analogy to the pKm for isocitrate, on the enzyme-glyoxylate-inhibitor complex.
Aqueous Stability of Gadolinium in Surface Waters Receiving Sewage Treatment Plant Effluent, Boulder Creek, Colorado

In many surface waters, sewage treatment plant (STP) effluent is a substantial source of both regulated and unregulated contaminants, including a suite of complex organic compounds derived from household chemicals, pharmaceuticals, and industrial and medical byproducts. In addition, STP effluents in some urban areas have also been shown to have a positive gadolinium (Gd) anomaly in the rare earth element (REE) pattern, with the Gd derived from its use in medical facilities. REE concentrations are relatively easy to measure compared to many organic wastewater compounds and may provide a more widely utilized tracer of STP effluents. To evaluate whether sewage treatment plant-associated Gd is a useful tracer of treatment plant effluent, an investigation of the occurrence, fate, and transport of rare earth elements was undertaken. The rare earth element patterns of four of five STP effluents sampled display positive Gd anomalies. The one site that did not have a Gd anomaly serves a small community, population 1200, with no medical facilities. Biosolids from a large metropolitan STP are not enriched in Gd even though the effluent is, suggesting that a substantial fraction of Gd remains in the aqueous phase through routine treatment plant operation. To evaluate whether STP-derived Gd persists in the fluvial environment, a 14-km study reach downstream of an STP was sampled. Gadolinium anomalies were present at all five downstream sites, but the magnitude of the anomaly decreased. Effluent from STPs is a complex mixture of organic and inorganic constituents, and to better understand the chemical interactions and their effect on REEs, the aqueous speciation was modeled using comprehensive chemical analyses of water samples collected downstream of STP input. These calculations suggest that the REEs will likely remain dissolved because phosphate and carbonate complexes dominate over free REE ions. This study supports the application of Gd anomalies as a useful tracer of urban wastewater.
An enzyme based assay for differential determination of coumaphos and potasan in cattle dips

Abstract An enzyme‐based assay was developed to monitor the levels of the organophosphate acaricide coumaphos and potasan, a metabolite formed by reductive dechlorination in cattle dipping solutions. The assay relies on the differential rates of hydrolysis of coumaphos and potasan by the enzyme parathion hydrolase (organophosphorous anhydrase [EC 3.1.8.1]). Hydrolysis of coumaphos and potasan yields the fluorescent products chlorferon and 4‐methylumbelliferone, respectively. By altering the reaction conditions and measuring the formation of fluorescent compounds in two parallel reactions (one reaction for potasan hydrolysis, one reaction for hydrolysis of potasan and coumaphos), it was possible to measure both coumaphos and potasan in samples from cattle dipping vats and from a bioreactor used for digestion of coumaphos‐containing wastes. This sensitive and reliable assay would be suited for use in remote field sites where more conventional chemical analysis is difficult to obtain.
Regional Evaluation of Ischemic Metabolic Alterations

Cerebral ischemia causes metabolic alterations that vary greatly in different regions of the brain. Even in the most uniform of ischemic episodes, i.e., complete cessation of flow, metabolic changes are regionally inhomogeneous. Further, the patchy per­ fusion that characterizes incomplete ischemia ac­ centuates the metabolic heterogeneity. F inally, in focal ischemia, metabolic perturbations in the isch­ emic focus are qualitatively different from those in adjacent tissue. Therefore, it is imperative that bio­ chemical studies of cerebral ischemia employ methods with appropriate spatial resolution.
DIFFICULTY OF A SPATIAL TASK AND SEX DIFFERENCE IN GAINS FROM PRACTICE

The influence of practice on a difficult spatial task in a small sample of 11 men and 16 women was investigated. Participants were tested on a rotated embedded figures task modified from the Gottschaldt Hidden Figure Test prior to being given practice in identifying rotated and nonrotated embedded figures. One week after the pretest and practice session, the posttest was given. In the small sample studied, the number of correctly identified rotated figures on the posttest was significantly increased relative to pretest scores for men and women. However, the tendency for women to score higher than men after practice was not significant.
Regulation of HIV-1 gag protein subcellular targeting by protein kinase C

The human immunodeficiency virus type 1 internal structural protein precursor, p55, and its corresponding matrix proteolytic fragment, p17, are phosphorylated at Ser111 by protein kinase C. COS-7 cells transfected with plasmids encoding either the wild-type or Ser111-->Ala mutated human immunodeficiency virus type 1 gag gene matrix domain proteins were treated with phorbol 12-myristate 13-acetate (PMA), and the phosphorylation of the expressed p17 proteins was examined by radioimmunoprecipitation, SDS-polyacrylamide gel electrophoresis, and autoradiography. PMA treatment of transfected cells resulted in a 4-5-fold increase in wild-type p17 (but not mutated p17) phosphorylation; however, mutated p17 exhibited a low basal level of phosphorylation that was not affected by PMA, suggesting that additional sites were phosphorylated. PMA treatment of cells expressing wild-type p17 produced a dramatic shift in the localization of p17 from the cytosol to the membrane fraction within 8-15 min, followed by a slow quantitative dissociation of p17 back into the cytosol by 90 min. The cytosol-to-membrane translocation was dependent on N-myristoylated p17 since cells expressing p17 with a Gly2-->Ala mutation did not localize to the membrane. PMA also failed to induce the translocation of fully N-myristoylated Ser111-->Ala p17, suggesting that p17 phosphorylation at Ser111 was responsible for membrane association. This conclusion was confirmed by the finding of phosphorylated wild-type p17 in the membrane fraction only after PMA treatment. These results suggest that a "myristoyl-protein switch" regulates the reversible membrane targeting of p17 by protein kinase C-mediated phosphorylation. This signal may provide a mechanism for the cellular regulation of virus development through modulation of gag protein-related developmental steps such as capsid targeting, assembly, encapsidation, budding, and maturation.
Symplastic continuity between mesophyll and companion cells in minor veins of mature Cucurbita pepo L. leaves.

Dye-coupling studies have been undertaken to determine whether plasmodesmata between intermediary cells (companion cells) and bundle-sheath cells in the minor veins of mature Cucurbita pepo L. leaves are open to passage of low-molecular-weight compounds. The abaxial phloem of these veins was exposed by stripping the lower epidermis of the leaf and removing the spongy-mesophyll cells by abrasion. Lucifer yellow, or 6-carboxyfluorescein, were microinjected into intermediary cells by iontophoresis, and dye location was monitored by fluorescence microscopy. Dye spread from one intermediary cell to another and from intermediary cells to bundle-sheath and mesophyll cells. No movement of microinjected dye occurred in some experiments, probably because plasmodesmata closed in response to cell damage incurred during tissue preparation. Most, but not all, minor veins in tissue prepared for microinjections studies are able to accumulate exogenously supplied [14C]sucrose. Plasmolysis studies indicate that the solute content of intermediary cells is much higher than that of bundle-sheath cells. In C. pepo, plasmodesmata may provide a route for the selective phloem loading of export sugars.
Clinical spectrum of posterior ischemic optic neuropathy.

Abstract PURPOSE : To describe the systemic and visual characteristics and prognosis in patients with posterior ischemic optic neuropathy (PION). DESIGN : Observational case series. METHODS : Retrospective chart review in a multicenter setting. Seventy-two patients (98 eyes) with a clinical diagnosis of PION. Co-morbid systemic diseases and visual function were recorded at both initial presentation and after mean visual follow-up of 4.1 years and systemic follow-up of 5.4 years. RESULTS : PION occurred in three main settings: in the perioperative period following a variety of surgical procedures (28 patients), associated with giant cell (temporal) arteritis (6 patients), and associated with nonarteritic systemic vascular disease (38 patients). Patients with perioperative and arteritic PION were more likely to have severe, bilateral visual loss that did not improve. Among eyes with nonarteritic PION, 34% experienced improvement in vision, 28% remained stable, and 38% worsened. Among patients with nonarteritic PION, carotid artery disease and a history of stroke (with or without carotid artery disease) were both associated with a statistically significant increased risk of poor final visual outcome. CONCLUSIONS : There are three distinct subtypes of PION: perioperative, arteritic, and nonarteritic. Patients with PION that is unassociated with surgery should undergo an evaluation for systemic vascular diseases, including giant cell arteritis, that may or may not be apparent at the time of vision loss. The visual prognosis for patients with perioperative or arteritic PION is poor, whereas that for nonarteritic PION is similar to that for patients with nonarteritic AION.
Rate structure effects and regression parameter instability across time-of-use electricity pricing experiments

Abstract Using a pool of data from eleven time-of-use (TOU) pricing experiments, a consumer demand model is estimated, and simple but statistically exact tests are performed for rate structure parameter instability across these experiments. Rate structure effects considered in the analyses concern the length of time (during the demand cycle) that the respective prices are charged, intermediate pricing periods, demand versus energy charges, and voluntary versus mandatory participation. Pricing period length and energy charges are found to have significant effects but the significance of others rate structure effects are generally mixed. The hypotheses of parameter instability are accepted, in a number of cases, across experiments but rejected through time.
Inactive transfer policies and efficiency in general overlapping-generations economies

Abstract I analyze how public debt restores Pareto efficiency in overlapping-generations economies. My model allows non-stationarity across time and accommodates many heterogeneous and multiperiod lived agents per generation and goods per period. I show that efficiency can always be restored by a once-and-for-all augmentation of initial wealth (the introduction of debt) partially financed by a series of ‘small’ taxes (the summation of average tax rates being less than any prescribed tolerance). I reconcile this positive result with well-known counter-examples. To establish my general proposition, I extend to my model Cass' well-known price characterization of efficiency.
Capsule commentary on Mukhtar et al., Assessment of HBV preventive services in a medically underserved Asian and Pacific Islander population using provider and patient data.

Editor's note: This capsule commentary was to accompany “Assessment of HBV Preventive Services in a Medically-Underserved Asian and Pacific Islander Population Using Provider and Patient Data,” which was published in the January 2015 issue. The Editors apologize for this error. Death from cirrhosis and hepatocellular carcinoma related to chronic hepatitis B and C is preventable with current therapies. Recommendations by the US Preventative Services Task Force (USPSTF) include testing for hepatitis C in persons born between 1945 and 1965 and for hepatitis B in persons at high risk of infection, including those born in all of Asia, Eastern Europe, and most of Africa. Currently, fewer than half of the estimated 2 million cases of hepatitis B have been diagnosed and only a fraction of those infected are being adequately managed.1,2 The study by Mukhtar and colleagues highlights some of the barriers to hepatitis B screening.3 Not surprisingly, testing rates for hepatitis B were positively associated with provider attitudes and negatively associated with providers’ perceived barriers to testing. Notably, provider knowledge was not associated with testing. Thus, shifting provider attitudes and reducing barriers to care might be more effective than improving provider knowledge. With new USPSTF recommendations supporting testing, we might anticipate improvement in the provider factors that limit testing of hepatitis B. However, practical issues in primary care may overshadow these improvements. As noted by Mukhtar et al., patient load had a strong negative effect on hepatitis B testing. An additional preventative test is likely to have low uptake by busy clinicians in practices where high-risk patients are the minority. Alternative approaches addressing patient barriers, leveraging of electronic medical records (EMR), and utilizing case management strategies are more likely to lead to higher rates of testing. Though the absolute effect was small, culturally appropriate patient education administered by bicultural lay health workers significantly increased testing for hepatitis B in an underserved Asian community.4 Of greater impact was the use of an electronic messaging system to alert providers of the testing recommendations prior to a visit by a high-risk patient.5 This intervention increased hepatitis B test ordering from less than 2 % to 40 % for a single visit. Importantly, testing alone will not prevent hepatitis B-related deaths. Evaluation, monitoring, and treatment of infected individuals is needed and well suited for a collaborative case management strategy overseen by primary care providers and specialists.
Controlling the in vitro release profiles for a system of haloperidol-loaded PLGA nanoparticles

We have used a systematic methodology to tailor the in vitro drug release profiles for a system of PLGA/PLA nanoparticles encapsulating a hydrophobic drug, haloperidol. We applied our previously developed sonication and homogenization methods to produce haloperidol-loaded PLGA/PLA nanoparticles with 200-1000 nm diameters and 0.2-2.5% drug content. The three important properties affecting release behavior were identified as: polymer hydrophobicity, particle size and particle coating. Increasing the polymer hydrophobicity reduces the initial burst and extends the period of release. Increasing the particle size reduces the initial burst and increases the rate of release. It was also shown that coating the particles with chitosan significantly reduces the initial burst without affecting other parts of the release profile. Various combinations of the above three properties were used to achieve in vitro release of drug over a period of 8, 25 and >40 days, with initial burst <25% and a steady release rate over the entire period of release. Polymer molecular weight and particle drug content were inconsequential for drug release in this system. Experimental in vitro drug release data were fitted with available mathematical models in literature to establish that the mechanism of drug release is predominantly diffusion controlled. The average value of drug diffusivities for PLGA and PLA nanoparticles was calculated and its variation with particle size was established.
Theoretical overview of electronic structure and bonding of adsorbates

Abstract We consider the methods of recent computational studies which explore the electronic structure and bonding of adsorbates at metal surfaces. The emphasis is on the concepts one can obtain from such studies, especially with respect to the connection between various spectroscopic data and bonding. Some specific and important electronic correlation effects are pointed out — for both the adsorbate and the metal. Many of the theoretical and conceptual issues are illustrated by an in-depth analysis of the chemisorption of N 2 and CO on nickel.
Optimizing communication and capacity in a 3D stacked reconfigurable cache hierarchy

Cache hierarchies in future many-core processors are expected to grow in size and contribute a large fraction of overall processor power and performance. In this paper, we postulate a 3D chip design that stacks SRAM and DRAM upon processing cores and employs OS-based page coloring to minimize horizontal communication of cache data. We then propose a heterogeneous reconfigurable cache design that takes advantage of the high density of DRAM and the superior power/delay characteristics of SRAM to efficiently meet the working set demands of each individual core. Finally, we analyze the communication patterns for such a processor and show that a tree topology is an ideal fit that significantly reduces the power and latency requirements of the on-chip network. The above proposals are synergistic: each proposal is made more compelling because of its combination with the other innovations described in this paper. The proposed reconfigurable cache model improves performance by up to 19% along with 48% savings in network power.
COVALENT LINKAGE OF C3 TO PROPERDIN DURING COMPLEMENT ACTIVATION

Activation of the alternative complement pathway of serum produces complexes of properdin (P) and C3 as measured in a double antibody enzyme-linked immunosorbent assay. When purified from serum, these complexes decrease factor B hemolytic activity in serum and do not restore the alternative pathway hemolytic activity of serum deficient in P. Sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of activated serum containing biotinylated P, followed by blotting to nitrocellulose and development with streptavidin-alkaline phosphatase revealed a band at 53 kDa for monomeric P and an additional band at 160 kDa. P samples eluted from zymosan and purified from activated serum revealed a band at 116 kDa for C3 alpha and 74 kDa for C3 beta, and an additional band at 160 kDa when analyzed by SDS-PAGE, Western blotting and development with antibody to C3. The appearance of a 160 kDa band containing P and C3 indicates that these proteins are contained in a complex formed during activation of the alternative pathway. Activation of a purified reagent mixture containing factors B, D, and H, and 125I-labeled P or 125I-labeled C3, followed by SDS-PAGE and autoradiography confirmed the presence of a 160-kDa band which disappeared following hydroxylamine treatment of the sample. These data are consistent with a covalent linkage of C3 to P via the C3 alpha chain, producing the 160-kDa complex.
Studies of Collagen Tissue Aging Thermal Shrinkage of Metabolite-Treated Collagenous Tissues.

SummaryThe thermal shrinkage of a number of collagenous tissues (skin, aorta, tendon, and decalcified bone) has been studied following incubation with a series of carbohydrate metabolites. The data indicate that only glyceraldehyde among the metabolites studied here, is capable of acting as a tanning or cross-linking agent for collagen under a variety of experimental conditions. These latter roughly approximate the pH, ionic strength and temperature conditions of the extracellular body fluids.
Does biopsy, aspiration or six-month follow-up of a false-positive mammogram reduce future screening or have large psychosocial effects?1

Abstract Rationale and Objectives. To determine the differences in the psychosocial effects and future mammography screening behavior between women who had an abnormal mammogram followed either by percutaneous or open surgical breast biopsy or cyst aspiration, or by short-term follow-up mammography to provide insight to radiologists making decisions regarding work-up. Materials and Methods. A structured interview was administered to women who recently had abnormal mammograms, leading to biopsy or aspiration (170 cases), or short-term follow-up (176 controls), by telephone within a month of the eligibility event and again approximately 15 months later. Information was collected on perceived pain/discomfort, interactions with medical staff, emotional impact, general breast cancer knowledge, patient attitude towards early diagnosis of breast cancer, perceived risk, previous and intended screening behavior, and subjective health status. Wilcoxon rank sum statistical test was used to compare the two groups at the time of both interviews. Results. Cases and controls had similar demographics. There were no significant differences in the examined psychosocial effects and reported intention to undergo future screening mammography between cases and controls. The overwhelming majority of both cases and controls both reported intention to and underwent routine screening 15 months after the eligibility event. Conclusion. Undergoing a biopsy, cyst aspiration, or 6-month follow-up after a positive mammogram does not have large psychosocial effects, nor does it deter women from undergoing screening mammography in the future.
The weighted sum method for multi-objective optimization: new insights

As a common concept in multi-objective optimization, minimizing a weighted sum constitutes an independent method as well as a component of other methods. Consequently, insight into characteristics of the weighted sum method has far reaching implications. However, despite the many published applications for this method and the literature addressing its pitfalls with respect to depicting the Pareto optimal set, there is little comprehensive discussion concerning the conceptual significance of the weights and techniques for maximizing the effectiveness of the method with respect to a priori articulation of preferences. Thus, in this paper, we investigate the fundamental significance of the weights in terms of preferences, the Pareto optimal set, and objective-function values. We determine the factors that dictate which solution point results from a particular set of weights. Fundamental deficiencies are identified in terms of a priori articulation of preferences, and guidelines are provided to help avoid blind use of the method.
Rac1 targeting suppresses p53 deficiency-mediated lymphomagenesis.

Mutation of the p53 tumor suppressor is associated with disease progression, therapeutic resistance, and poor prognosis in patients with lymphoid malignancies and can occur in approximately 50% of Burkitt lymphomas. Thus, new therapies are needed to specifically target p53-deficient lymphomas with increased efficacy. In the current study, the specific impact of inhibition of the small GTPase Rac1 on p53-deficient B- and T-lymphoma cells was investigated. p53 deficiency resulted in increased Rac1 activity in both B-cell and T-cell lines, and its suppression was able to abrogate p53 deficiency–mediated lymphoma cell proliferation. Further, Rac targeting resulted in increased apoptosis via a p53-independent mechanism. By probing multiple signaling axes and performing rescue studies, we show that the antiproliferative effect of Rac1 targeting in lymphoma cells may involve the PAK and Akt signaling pathway, but not the mitogen-activated protein (MAP) kinase pathway. The effects of inhibition of Rac1 were extended in vivo where Rac1 targeting was able to specifically impair p53-deficient lymphoma cell growth in mouse xenografts and postpone lymphomagenesis onset in murine transplantation models. Because the Rac1 signaling axis is a critical determinant of apoptosis and tumorigenesis, it may represent an important basis for therapy in the treatment of p53-deficient lymphomas.
Catalytic oxidation of graphite by iridium and rhodium

Abstract Controlled atmosphere electron microscopy has been used to investigate the catalytic influence of iridium and rhodium on the graphite-oxygen reaction. Both systems were found to exhibit a similar behavioral pattern. As the temperature was raised, the initial catalytic action was followed by a short period of inactivity before a second, more intense catalytic attack occurred at temperatures >1000 °C. It is probable that the two activity regions correspond to the existence of oxides, IrO 2 and Rh 2 O 3 at the lower temperatures and the respective metals at temperatures >1000 °C. This pattern is quite different than that found for platinum and palladium, which are present in the metallic state throughout the gasification sequence and as a consequence exhibit only a single continuous catalytic action on the graphite-oxygen reaction. Another aspect revealed from these experiments is the manner by which iridium and rhodium particles supported on graphite sinter in an oxidizing environment. Atomic migration accounts for the growth of inactive particles below the Tammann temperature for the metal (1110 °C for iridium; 910 °C for rhodium); above this temperature the overriding mode of growth is via particle migration. Particle mobility on graphite can occur below the Tammann temperature as the catalytic channeling action induces motion into active particles.
Dialect, trope, and enregisterment in a Melanesian speech community

Abstract This paper examines the enregisterment of dialect shibboleths among the Yopno of Papua New Guinea. The Yopno recognize dialect shibboleths as indexes of a speaker’s “home village,” yet people employ dialect shibboleths associated with others’ villages in systematic ways, offering little explicit metapragmatic commentary about such uses. Through the analysis of two interactional events, this paper demonstrates how the social meaning of using another’s dialect shibboleths is generated through figures of speech (i.e. tropes) that are manifest in the implicit metapragmatic structuring of discourse through parallelism. Though much work on enregisterment foregrounds the role of explicit metapragmatic discourse in the process, this case highlights the important role played by tropes figured in the implicit metapragmatic structuring of discourse.
Semi-exact concentric atomic density fitting: reduced cost and increased accuracy compared to standard density fitting.

A local density fitting scheme is considered in which atomic orbital (AO) products are approximated using only auxiliary AOs located on one of the nuclei in that product. The possibility of variational collapse to an unphysical “attractive electron” state that can affect such density fitting [P. Merlot, T. Kjaergaard, T. Helgaker, R. Lindh, F. Aquilante, S. Reine, and T. B. Pedersen, J. Comput. Chem. 34, 1486 (2013)] is alleviated by including atom-wise semidiagonal integrals exactly. Our approach leads to a significant decrease in the computational cost of density fitting for Hartree–Fock theory while still producing results with errors 2–5 times smaller than standard, nonlocal density fitting. Our method allows for large Hartree–Fock and density functional theory computations with exact exchange to be carried out efficiently on large molecules, which we demonstrate by benchmarking our method on 200 of the most widely used prescription drug molecules. Our new fitting scheme leads to smooth and artifact-free potential energy surfaces and the possibility of relatively simple analytic gradients.
Neutron radiotherapy for adenoid cystic carcinoma of the head and neck.

• Achieving local control in patients with advanced adenoid cystic carcinoma continues to be a therapeutic challenge. From 1984 to 1990, we treated 34 patients with advanced adenoid cystic carcinoma of the head and neck with fast neutron radiation. Patients treated for minimal microscopic disease following surgery were not included in this study. Neutron radiotherapy achieved 5-year actuarial local control and locoregional control rates of 76% and 63%, respectively. Five-year actuarial overall survival and disease-specific survival rates were 65% and 93%, respectively. Eighty-one percent (17/21) of patients treated with neutron therapy alone and 100% (13/13) of the patients treated with neutron therapy and surgery achieved local control. All seven patients with paranasal sinus malignant neoplasms achieved local control. The success achieved in this prognostically unfavorable population affirms the important role of neutron radiotherapy in the treatment of adenoid cystic carcinoma. ( Arch Otolaryngol Head Neck Surg. 1993;119:747-752)
Tropospheric chemistry of internally mixed sea salt and organic particles: Surprising reactivity of NaCl with weak organic acids

Chemical imaging analysis of internally mixed sea salt/organic particles collected on board the Department of Energy (DOE) G-1 aircraft during the 2010 Carbonaceous Aerosols and Radiative Effects Study (CARES) was performed using electron microscopy and X-ray spectro-microscopy techniques. Substantial chloride depletion in aged sea salt particles was observed, which could not be explained by the known atmospheric reactivity of sea salt with inorganic nitric and sulfuric acids. We present field evidence that chloride components in sea salt particles may effectively react with organic acids releasing HCl gas to the atmosphere, leaving behind particles depleted in chloride and enriched in the corresponding organic salts. While formation of the organic salts products is not thermodynamically favored for bulk aqueous chemistry, these reactions in aerosol are driven by high volatility and irreversible evaporation of the HCl product from drying particles. These field observations were corroborated in a set of laboratory experiments where NaCl particles mixed with organic acids were found to be depleted in chloride. Combined together, the results indicate substantial chemical reactivity of sea salt particles with secondary organics that has been largely overlooked in the atmospheric aerosol chemistry. Atmospheric aging, and especially hydration-dehydration cycles of mixed sea salt/organic particles may resultmore » in formation of organic salts that will modify acidity, hygroscopic and optical properties of aged particles.« less
An Analytical Solution for Calculating Stresses on Lap Patches Used on Pipes and Pressure Vessels

Lap patch repairs are used regularly in petrochemical industries as temporary repairs for short term operations. In this paper a simple methodology is proposed on how to calculate the stresses on a lap patch using simple analytical approximation. The simple analytical results are compared with finite element results and they are found to be in reasonable agreement.Copyright © 2008 by ASME
Thin-Layer Chromatography of Plant Pigments on Mannitol or Sucrose

Fat-soluble tobacco leaf pigments were separated by chromatography on thin layers of mannitol and sucrose. Resolution of pigments, simplicity, and rapidity of preparation and development offer advantages over previous methods.
Reconstruction Technique for Reducing Hybrid-Rocket Combustion Test Data

A new integral technique has been developed for the purpose of analyzing combustion test data in hybrid rocket firings. The method, which utilizes a complete reconstruction of the regression history, is shown to have several advantages when compared with the current endpoint technique, in which average regression rate and port mass flux are determined based on fuel grain initial and final dimensions. One significant advantage is that the integral method permits one to ascertain the sensitivity of regression rate to changes in mass flux in a single test. Action (burning) times greater than 5 s have been found to be preferred over shorter values more typically used to date, because this minimizes errors in action time determination and permits the fuel to reach a steady-state thermal profile.
Molecular weights and spectral characteristics of humic and fulvic acids

Abstract Gel-filtration of humic and fulvic acid with Sephadex G-50 yielded low and high molecular weight fractions with different chemical and spectral characteristics. In contrast to the low molecular weight fraction, high molecular weight humic acid was insoluble in H 2 O and had a strong infrared C-H absorption at 2,900 cm −1 . Both humic acid fractions had lower E 4 /E 6 values than fulvic acids, and no correlation could be found between humic acids partition coefficient (K d ) and E 4 /E 6 ratio. Low molecular weight fulvic acid was higher in K d and E 4 /E 6 values than high molecular weight fulvic acid. In this case, a positive correlation was observed between K d and E 4 /E 6 .
SYNTHESIS AND PHARMACOLOGY OF SOME BASIC ESTERS OF 3,4,5-TRIMETHOXYBENZOIC ACID.

A series of basic esters of 3,4,5-trimethoxybenzoic acid has been synthesized and the compounds evaluated for antihypertensive and local anesthetic activity. One of the compounds, a diamine ester prepared from N-methyl-N-phenyl-N′-propyl-ethylenediamine via a three-step synthesis, exhibited hypotensive activity following intravenous administration to normotensive dogs. No hypotensive activity was demonstrated following intraperitoneal administration to renal hypertensive rats. All but one of the compounds tested exhibited some degree of local anesthetic activity.
Optimal infinite impulse response zero crossing based edge detectors

We present formal optimality criteria and a complete design methodology for a family of zero crossing based, infinite impulse response (recursive) edge detection filters. In particular, we adapt the optimality criteria proposed by Canny (IEEE Trans. Pattern Anal. Mach. IntelligencePAMI-8, 1986, 679–714) to filters designed to respond with a zero crossing in the output at an edge location and additionally to impulse responses which are (allowed to be) infinite in extent. The spurious response criterion is captured directly by an appropriate measure of filter spatial extent for infinite responses. Infinite duration impulse responses may be implemented efficiently with recursive filtering techniques and so require constant computation time with respect to scale. As we will show, we can achieve both superior performance and increased speed by designing directly for an infinite impulse response than by any of the proposed finite duration approaches. We also show that the optimal filter which responds with a zero crossing in its output may not be implemented by designing the optimal peak responding filter (similar to Canny) and taking an additional derivative. It is necessary to formulate the criteria and design for a zero crossing response from the outset, else optimality is sacrificed. Filter parameters and performance criteria are presented for several designs, and experimental results are presented on a variety of images which demonstrate the behavior in the presence of very adverse noise, with respect to scale, and as compared to other “optimal” IIR filters which have been reported.
Analysis of AlGaAs-GaInAs cascade solar cell under AM 0-AM 5 spectra

Abstract It has been shown from first principles, using the integral form of the transport equations, that the efficiency of a two-junction AlGaAs-GaInAs cascade solar cell optimized at 290°K and under AM 0 spectral conditions may exceed 30%. Further studies of this cascade structure have been carried out to determine performance under AM 0-AM 5 spectral conditions and at a concentration ratio of 103 over the temperature range 290–600°K. In addition, the two-junction AlGaAs-GaInAs cascade cell has been optimized at 290°K and under AM 1.5 spectral conditions. The performance characteristics of the designs optimized under AM 0 and AM 1.5 conditions are compared over the temperature range 290–600°K. The AM 0 optimized structure was used as the initial structure to determine the optimized structure under AM 1.5 spectral conditions. The results of the computer modeling show that the optimized wide bandgap cell parameters under AM 0 and AM 1.5 are somewhat different. However, the optimized narrow bandgap cell parameters are identical for AM 0 and AM 1.5. The theoretical efficiency increases with increasing concentration ratio, approaching 40% at 103 concentration ratio.
Lithium-Assisted Plastic Deformation of Silicon Electrodes in Lithium-Ion Batteries: A First-Principles Theoretical Study

Silicon can host a large amount of lithium, making it a promising electrode for high-capacity lithium-ion batteries. Recent experiments indicate that silicon experiences large plastic deformation upon Li absorption, which can significantly decrease the stresses induced by lithiation and thus mitigate fracture failure of electrodes. These issues become especially relevant in nanostructured electrodes with confined geometries. On the basis of first-principles calculations, we present a study of the microscopic deformation mechanism of lithiated silicon at relatively low Li concentration, which captures the onset of plasticity induced by lithiation. We find that lithium insertion leads to breaking of SiSi bonds and formation of weaker bonds between neighboring Si and Li atoms, which results in a decrease in Young's modulus, a reduction in strength, and a brittle-to-ductile transition with increasing Li concentration. The microscopic mechanism of large plastic deformation is attributed to continuous lithium-assisted breaking and re-forming of SiSi bonds and the creation of nanopores.
Stimulation of protein tyrosine phosphorylation by NMDA receptor activation

The N-methyl-D-aspartate (NMDA) receptor, a subtype of glutamate receptors, plays a key role in synaptic plasticity in the nervous system. After NMDA receptor activation, calcium entry into the postsynaptic neuron is a critical initial event. However, the subsequent mechanisms by which the NMDA receptor signal is processed are incompletely understood. Stimulation of cultured rat hippocampal cells with glutamate resulted in the rapid and transient tyrosine phosphorylation of a 39-kilodalton protein (p39). Tyrosine phosphorylation of p39 was triggered by the NMDA receptor and required an influx of Ca2+ from the extracellular medium. Because p39 was found to be highly related or identical to the microtubule-associated protein 2 kinase, the NMDA receptor signal may be processed by a sequential activation of protein kinases.
The Uses and Abuses of Prayer Book Properties in Hamlet, Richard III, and Arden of Faversham

AbstractProtestant polemicists attempted to articulate a clear opposition between word and image, depicting the faithful as godly readers who eschewed idolatrous objects such as rosaries and crucifixes. But even reformed prayer involved the use of textual guides, and because of their materiality these prayer manuals flew in the face of theologians' claims that they had eliminated all of the superficial trappings associated with Catholic worship. This essay addresses scenes of prayer book use in Hamlet, Richard III, and Arden of Faversham, arguing that each of these plays draws attention to existing contradictions surrounding the idealized image of the godly reader by highlighting the slippage between theatrical and religious practice, both of which employed prayer books as “props.” (E.W.)
Fixed poles, t-channel unitarity, and rising cross-sections

Abstract If the Pomeron is a fixed pole, it must be “shielded” from t -channel unitarity by a special type of cut. We show how to obtain such a cut. There are no arbitrary parameters between the cut and the pole, and definite predictions of rising cross-sections, shrinkage and (Re F )/(Im F ) result. These are found to be in good agreements with high energy data. Previously we obtained a very similar cut (with similar fits), but we no longer require use of an exotic trajectory.
Linear Mappings which Preserve Paracontractions

It shown that a linear, surjective mapping which preserves paracontractions in both directions (relative to Euclidean norm) is an (anti)isometry. This is no longer the case if it preserves paracontractions in one direction only.
Evaluation of zinc availability in foodstuffs of plant and animal origin.

Growth response of chicks and rats was used to evaluate the biological availability of zinc in selected cereal grains and animal products. Two sources of protein, soybean and casein-gelatin, were used in the basal low zinc diets and graded levels of ZnCOs were added to establish the standard response curve. Thus, the availability values are based on the assumption that 100% of the zinc in ZnCO3 is available. A plot of weight gain during a 4-week period versus the logarithm of zinc added gave a straight line relationship over the range of 3 to 12 ppm. The 5 to 10 ppm range was used to evaluate the supple ments which were added to the basal diets in lieu of carbohydrate. The minimum zinc requirement for chicks and rats fed the soybean protein diets was 19 ppm and for chicks fed the casein-gelatin diet it was 12 ppm. The following biological availabilities were obtained by use of the chick assay: high lysine corn 65%, control corn 63%, rice 62%, wheat 59%, high lysine corn germ 56%, control germ 54%, sesame meal 59%, soybean meal 67%, egg yolk 79%, fish meal 75%, oysters 95%, and nonfat milk 82%. The rat assay gave: high lysine corn 55%, control corn 57%, wheat 38%, rice 39%, egg yolk 76%, nonfat milk 79% and fish meal 84% . In general the zinc in plant seeds was less available than that in animal products, and rats utilized the zinc in plant seeds less well than chicks. J. Nutr. 102: 653-660, 1972.
System optimization in digital color imaging

The work presents an overview of a color imaging system and its elements and then highlights techniques in the literature that attempt to account for system interactions for improved quality or performance. After that, presented in greater detail, are two specific examples of approaches that take into account interactions between elements that are normally treated independently. Finally, concluding remarks are presented.
Detergent‐insoluble glycosphingolipid/cholesterol microdomains of the myelin membrane

Glycosphingolipids and cholesterol form lateral assemblies, or lipid ‘rafts’, within biological membranes. Lipid rafts are routinely studied biochemically as low-density, detergent-insoluble complexes (in non-ionic detergents at 4°C; DIGs, detergent-insoluble glycosphingolipid/cholesterol microdomains). Recent discrepancies recommended a re-evaluation of the conditions used for the biochemical analysis of lipid rafts. We have investigated the detergent insolubility of several known proteins present in the glycosphingolipid/cholesterol-rich myelin membrane, using four detergents representing different chemical classes (TX-100, CHAPS, Brij 96 and TX-102), under four conditions: detergent extraction of myelin either at (i) 4°C or (ii) 37°C, or at 4°C after pre-extraction with (iii) saponin or (iv) methyl-β-cyclodextrin (MβCD). Each detergent was different in its ability to solubilize myelin proteins and in the density of the DIGs produced. Brij 96 DIGs floated to a lower density than other detergents tested, possibly representing a subpopulation of DIGs in myelin. DIGs pre-extracted with saponin were denser than DIGs pre-extracted with MβCD. Furthermore, pre-extraction with MβCD solubilized proteolipid protein (known to associate with cholesterol), whereas pre-extraction with saponin did not, suggesting that saponin is less effective as a cholesterol-perturbing agent than is MβCD. These results demonstrate that DIGs isolated by different detergents are not necessarily comparable, and that these detergent-specific DIGs may represent distinct biochemical, and possibly physiological, entities based on the solubilities of specific lipids/proteins in each type of detergent.
Constructing Self-Enforcing Federalism in the Early United States and Modern Russia

All federal systems face the two fundamental dilemmas of federalism: too strong a center risks overawing the subnational units; and too weak a center risks free-riding that makes the system fall apart. Resolving the two dilemmas is problematic because mitigating one dilemma exacerbates the other. We develop a model of federal institutions that shows the circumstances under which both dilemmas can be solved so that federal institutions are self-enforcing. We apply our approach to modern Russia where we suggest that when the center is too strong, its ability to extract rents increases and the benefits for maintaining participation in the federal bargain disappears. We also suggest strong parallels between Russia and those of the early United States under the Articles of Confederation. Copyright 2007, Oxford University Press.
“WE ARE RESEARCHERS”: STUDENTS WITH AND WITHOUT INTELLECTUAL DISABILITIES RESEARCH THE UNIVERSITY EXPERIENCE IN A PARTICIPATORY ACTION RESEARCH COURSE

This article describes an undergraduate Participatory Action Research (PAR) course in which students with and without intellectual disabilities collaborated as co-researchers in order to explore various aspects of the university experience. The article describes the university course as well as presents results of the students’ PAR projects. The students’ PAR projects revealed that (a) eating healthy at the university was challenging, expensive, and at times, impossible; (b) although University of Vermont (UVM) is thought by many to be a haven for social justice, misunderstanding of and discrimination against students who identify as transgendered occur on the campus; and (c) students’ home cultures often clash with the mainstream
Social Context of Performance Evaluation Decisions

The role of social and situational influences in the performance-rating process has received relatively little research attention yet merits increased attention. Although there has been acknowledgm...
Application of high-performance aerogel insulating materials (analysis & test results)

The NCSX stellarator core design is built around a 3-period, highly shaped plasma with an assembly of four magnet systems, the TF coils (TF), the Modular Coils (MC), the PF Coils (PF), and the Trim Coils, that surrounds an all welded Vacuum Vessel (VV). The VV features approximately 100 ports for heating, pumping, diagnostics, and maintenance access. The entire system is surrounded by a cryostat to permit operation of the coils at liquid nitrogen temperature. The VV and coils are assembled in 120° segments. The VV segments must be placed inside the MC by sliding the coils over each end of the vessel subassembly. Installation of the port extensions is done after this operation. They are slipped through access holes in the MC onto port stubs and welded on from inside. Figures 1 & 2 illustrate the assembly of the MC over a VV section and installation of TF and port extensions to complete a sector of the VV.
Report of the 2008-2009 Professional Affairs Committee: The academy's leadership agenda for meeting academic and practice workforce demands through postgraduate professional education.

issues associated with professional practice as theyrelate to pharmaceutical education, and to establishand improve working relationships with all other or-ganizations in the field of health affairs. The Commit-tee is also encouraged to address related agenda itemsrelevant to its Bylaws charge and to identify issues forconsideration by subsequent committees, task forces,commissions, or other groups.