cssi/SciSciGPT-SciSciNet huggingface dataset:
A Local Gradient Theory for Structural Forces in Thin Fluid Films

Abstract The gradient theory is applied to a thin liquid film between two flat surfaces. In the spirit of the gradient theory, the free energy functional is written in terms of the order parameter (φ). A lattice model is used to physically interpret the model parameters. The approach enables us to consider a generalization of the Marcelja and Radic (Chem. Phys. Lett. 42, 129 (1976)) and Cahn (J. Chem. Phys. 66, 3667 (1977)) models. We assume that the bulk free energy is an arbitrary function without inflection points (the possibility of a phase transition is excluded), and the short-range interactions between solids and fluid are considered. The model presented is shown to have an exact solution in implicit form. The qualitative behavior of the solution in the interlayer region is illustrated through the phase plane method, and the corresponding dependence of the pressure acting on both surfaces is derived. When the film thickness is much larger than the intermolecular separation distance, we develop an asymptotically exact technique for obtaining explicit relations between various thermodynamic parameters. In this limit, the disjoining pressure decays exponentially with film thickness. The parameter in the exponent term is the correlation radius of bulk liquid, and the preexponent factor includes the properties of the bounding surfaces and also takes into account the deviation of the bulk free energy from a quadratic form. It is shown that the disjoining pressure can be either positive or negative. Conditions for sign reversal are obtained in terms of the lattice model parameters for multicomponent liquids.
Are buybacks back? Menu-driven debt reduction schemes with heterogeneous creditors☆

Abstract We analyze the mechanics of menu-driven debt reduction deals, similar to those recently initiated by debtor countries, in which heterogeneous banks choose freely between selling or retaining their debt claims. We show that menu deals can facilitate discrimination across heterogeneous banks because of imperfections in the secondary market for debt. This implies that menu deals are likely to dominate market buybacks and pure concerted relending agreements, particularly when banks differ widely in their valuation of claims on the debtor.
Phagocytic and postphagocytic activities of bovine neutrophils for pure and mixed bacterial cultures.

Abstract A comparative study of phagocytosis and postphagocytic oxidative metabolic activity of bovine blood neutrophils incubated with pure and mixed cultures of Escherichia coli, Staphylococcus aureus , and Streptococcus agalactiae was performed. Most neutrophils when incubated with mixed cultures showed preferential phagocytosis for one species and a smaller number phagocytized both species of microorganisms. Percent phagocytosis for E. coli in pure culture was similar to that of Strep, agalactiae in pure culture and higher than that for Staph. aureus in pure culture. Neutrophils incubated with mixed cultures of E. coli and Staph. aureus or E. coli and Strep, agalactiae showed greater than expected phagocytosis of each microorganisms alone and reduced phagocytosis of both microorganisms together. Postphagocytic oxidative metabolic activity of neutrophils, measured by percent nitroblue tetrazolium reduction, did not differ following phagocytosis of these three microorganisms in pure cultures. In comparison, a synergistic effect on nitroblue tetrazolium reductive activity was seen in mixed cultures as evidenced by higher percent nitroblue tetrazolium reduction following phagocytosis of both E. coli and Staph. aureus or E. coli and Strep. agalactiae . These observations indicate that the phagocytic and metabolic activities of neutrophils for bacteria in mixed cultures may not be indentical to those in pure cultures.
Thyroglobulin gene activation by thyrotropin and cAMP in hormonally depleted FRTL-5 thyroid cells

Thyroglobulin gene control by cAMP and thyrotropin has been compared in FRTL-5 thyroid cells maintained in the absence of serum, insulin, cortisol, and thyrotropin for 7 days. Readdition of thyrotropin induces an increase in the expression of the thyroglobulin gene with little effect on total RNA synthesis. In contrast, addition of 8-bromo cyclic AMP and cholera toxin stimulate total RNA synthesis as well as thyroglobulin gene expression. The same non-selective effect of cyclic AMP on the thyroglobulin gene was observed when transcriptional activity was measured in permeabilized FRTL-5 cells.
Low-Temperature Plasma Jet for Biomedical Applications: A Review

Low-temperature plasma jets launched in room air are unique plasma sources in the sense that they provide a volume of plasma outside the confines of electrodes and gas enclosures. This is an extremely attractive property for medical applications where the target is usually a biological tissue located in normal and unobstructed room conditions. It was discovered that these jets are in fact trains of small volumes of plasma traveling at supersonic velocity. These fast propagating plasma fronts came to be known as plasma bullets. Plasma bullets are vehicles delivering reactive species such reactive oxygen species and reactive nitrogen species to a target under treatment. Here, a review of the biological and medical applications of a plasma jet source termed plasma pencil is presented. The plasma pencil is a device powered by short high-voltage pulses and that can launch plasma bullets in room air, up to several centimeters away from its nozzle. The effects of the plasma pencil on prokaryotic microorganisms (bacteria), pathogenic proteins, epithelial cells, and cancer cells are presented.
"Xanthomatous" changes in a papilloma of the choroid plexus.

A case of choroid plexus papilloma is reported with xanthomatous changes in the stroma. As in the non-neoplastic cases reported by Shuangshoti and Netsky, the lipid changes appeared to originate in the lining epithelium with secondary involvement of the stroma.
Fusarium Wilt of Strawberry Caused by Fusarium oxysporum in California.

Beginning in 2006 and continuing into 2009, an apparently new disease of strawberry (Fragaria × ananassa) affected commercial plantings (cvs. Albion, Camarosa, and others) in coastal (Ventura and Santa Barbara counties) California. Symptoms consisted of wilting of foliage, drying and withering of older leaves, stunting of plants, and reduced fruit production. Plants eventually collapsed and died. Internal vascular and cortical tissues of plant crowns showed a brown-to-orange-brown discoloration. Differences in cultivar susceptibility were not recorded. Internal crown and petiole tissues, when placed on acidified corn meal agar, consistently yielded Fusarium isolates having similar colony morphologies. No other pathogens were isolated. The Fusarium isolates were subcultured on carnation leaf agar and observed to be producing macroconidia and microconidiophores that are diagnostic of Fusarium oxysporum (1). For two of these isolates, the internal transcribed spacer region comprising ITS1, ITS2, and 5.8S rRN...
Response of Inorganic PM to Precursor Concentrations

An inorganic aerosol equilibrium model is used to investigate the response of inorganic particulate matter (PM) concentrations with respect to the precursor concentrations of sulfuric acid, ammonia, and nitric acid over a range of temperatures and relative humidities. Diagrams showing regions of PM response to precursor concentrations are generated, thus allowing the qualification of assumptions concerning the response of PM to sulfate and overall sensitivity to ammonia and nitric acid availability. The PM concentration level responds nonlinearly to sulfate and shows overall sensitivity to ammonia and nitric acid availability for specific atmospheric conditions and precursor concentrations. The generated diagrams are applied as a means of approximating the PM response to precursor concentrations for two urban polluted areas. In both cases, reductions in ammonia emissions have the most significant impact on the total PM level. However, such a reduction will result in significant increases in atmospheric acidity.
Take my paradigm … please! The legacy of Kuhn’s construct in educational research

Thomas Kuhn developed the construct of research paradigms to make sense of the history of conceptual change in the physical sciences. The construct has since been appropriated by a number of academic fields and by non‐academics as well. This paper traces the use of the construct in the educational research field. The bulk of the paper is organized around two questions: (a) Was it ever appropriate to characterize the educational research field’s acceptance of qualitative methods as equivalent to one of Kuhn’s paradigm revolutions? (b) Is paradigm talk appropriate today?
Contraband: The basis for legitimate power in a prison social system.

Much of the past literature on inmate socialization and social control in prison organizations has focused on the reciprocal relationships between key inmate leaders and members of the custodial st...
Potential-dependent reorientation of thiocyanate on Au electrodes.

Thiocyanate (SCN) adsorption on an Au electrode is examined using surface-enhanced Raman scattering (SERS) measurements, along with detailed density functional theory (DFT) calculations. Both the calculation and the spectroscopic measurements show that three different geometries are adopted by SCN adsorption in the potential region studied (0.0 V ≤ E ≤ 1.2 V vs NHE). At low potential both N-bound and S-bound forms are found, at intermediate potentials around the potential of zero charge (Epzc) the S-bound form dominates, and at high potentials SCN associates with the Au surface via a bridging geometry. The Stark slope observed for the C−N stretch in the N- and S-bound forms is positive, while the bridge form exhibits a negative Stark slope. DFT calculations show that the potential-dependent reorientation of SCN arises from overlap of specific SCN-based orbitals with the Fermi level of the Au surface; as the Fermi energy changes, different orbital overlaps are found. The calculations also provide an explan...
Atomic force microscopy reveals age-dependent changes in nanomechanical properties of the extracellular matrix of native human menisci: implications for joint degeneration and osteoarthritis

Abstract With aging, the menisci become more susceptible to degeneration due to sustained mechanical stress accompanied by age-related changes in the extracellular matrix (ECM). However, the mechanistic relationship between age-related meniscal degeneration and osteoarthritis (OA) development is not yet fully understood. We have examined the nanomechanical properties of the ECM of normal, aged, and degenerated human menisci using atomic force microscopy (AFM). Elasticity maps of the ECM revealed a unique differential qualitative nanomechanical profile of healthy young tissue: prominent unimodal peaks in the elastic moduli distribution in each region (outer, middle, and inner). Healthy aged tissue showed similar regional elasticity but with both unimodal and bimodal distributions that included higher elastic moduli. In contrast, degenerated OA tissue showed the broadest distribution without prominent peaks indicative of substantially increased mechanical heterogeneity in the ECM. AFM analysis reveals distinct regional nanomechanical profiles that underlie aging-dependent tissue degeneration and OA. From the Clinical Editor The authors of this study used atomic force microscopy to determine the nanomechanical properties of the extracellular matrix in normal and degenerated human menisci, as well as in menisci undergoing healthy aging. Comparison of these properties help to understand the relationship between healthy ageing, and age-dependent joint degeneration and osteoarthritis.
LRAT-specific domain facilitates vitamin A metabolism by domain swapping in HRASLS3

Cellular uptake of vitamin A, production of visual chromophore and triglyceride homeostasis in adipocytes depend on two representatives of the vertebrate N1pC/P60 protein family, lecithin:retinol acyltransferase (LRAT) and HRAS-like tumor suppressor 3 (HRASLS3). Both proteins function as lipid-metabolizing enzymes but differ in their substrate preferences and dominant catalytic activity. The mechanism of this catalytic diversity is not understood. Here, by using a gain-of-function approach, we identified a specific sequence responsible for the substrate specificity of N1pC/P60 proteins. A 2.2-A crystal structure of the HRASLS3-LRAT chimeric enzyme in a thioester catalytic intermediate state revealed a major structural rearrangement accompanied by three-dimensional domain swapping dimerization not observed in native HRASLS proteins. Structural changes affecting the active site environment contributed to slower hydrolysis of the catalytic intermediate, supporting efficient acyl transfer. These findings reveal structural adaptation that facilitates selective catalysis and mechanism responsible for diverse substrate specificity within the LRAT-like enzyme family.
Quantum Theory of Domain-Wall Motion

Several workers have examined the enhancement of nuclear magnetic resonance within a Bloch wall, and have demonstrated the existence of both bound and free "spin-wave" excitations on the Bloch wall structure. The free states correspond to precessional excitations akin to ordinary spin-wave excitations, while the bound states form a covenient basis for the representation of domain-wall motion. We derive the spectrum of both types of excitations, including exchange, anisotropy, and dipole field contributions for an infinite uniaxial ferromagnet. In contrast to earlier treatments, we treat the dipole field exactly (in the magnetostatic approximation), and show that this leads to a translational spectrum in which many states are degenerate with the "uniform translation," which is the translational mode excited by a uniform external magnetic field. The existence of such degeneracy is required for damping by imperfections to occur. The precessional spectrum is greatly different from the usual spin-wave spectrum, and, in particular, is not a symmetric function of k. The dipole fields lead to strong interactions, not conserving momentum, between the precessional modes; such interactions may explain the increase in ferromagnetic-resonance linewidth which is observed experimentally in the presence of a domain wall (in low dc magnetic fields). The motion of the domain wall, when it is bound to a certain position in the crystal by linear restoring forces, is studied by a Green's function technique. The domain-wall effective mass so obtained is identical to the expression given by D\"oring, and the domain-wall damping parameter proves to be simply related to the energy dispersion of the uniform translational mode. We calculate this energy dispersion due to scattering by the dipole fields, and due to "fluctuations," as used by Clogston et al. to explain the linewidth in disordered systems, such as the ferrites. The damping due to intrinsic scattering processes is proportional to ${T}^{2}$, while the damping due to "fluctuations" is essentially temperature-independent. In disordered systems, such as ferrite, the resonance line-width and domain-wall damping due to "fluctuations" should agree to within a factor of order unity. The motion is not describable by the Landau-Lifshitz equation. This communication is intended to demonstrate that a formulation for the quantum-mechanical study of domain-wall motion exists, and has the properties necessary to explain the losses which occur during such motion; it is not intended to lead to any quantitative results which can be directly compared with experiment. We also consider the specific heat contribution due to the domain wall, and we find that this is proportional to $T$ above about ${10}^{\ensuremath{-}2}$ \ifmmode^\circ\else\textdegree\fi{}K. It should be possible to observe such a specific heat contribution in YIG below 1 \ifmmode^\circ\else\textdegree\fi{}K.
[18F]-Fluorodeoxyglucose positron emission tomography in children with neurofibromatosis type 1 and plexiform neurofibromas: correlation with malignant transformation

The objective of this study was to investigate the predictive value of [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET) in detecting malignant transformation of plexiform neurofibromas in children with neurofibromatosis type 1 (NF1). An electronic search of the medical records was performed to determine patients with NF1 who had undergone FDG-PET for plexiform neurofibroma between 2000 and 2011. All clinical, radiologic, pathology information and operative reports were reviewed. Relationship between histologic diagnosis, radiologic features and FDG-PET maximum standardized uptake value (SUV(max)) was evaluated. This study was approved by the Institutional Review Board of our institution. 1,450 individual patients were evaluated in our Multidisciplinary Neurofibromatosis Program, of whom 35 patients underwent FDG-PET for suspected MPNST based on change or progression of clinical symptoms, or MRI findings suggesting increased tumor size. Twenty patients had concurrent pathologic specimens from biopsy/excision of 27 distinct lesions (mean age 14.9 years). Pathologic interpretation of these specimens revealed plexiform and atypical plexiform neurofibromas (n = 8 each), low grade MPNST (n = 2), intermediate grade MPNST (n = 4), high grade MPNST (n = 2), GIST (n = 1) and non-ossifying fibroma (n = 1). SUV(max) of plexiform neurofibromas (including typical and atypical) was significantly different from MPNST (2.49 (SD = 1.50) vs. 7.63 (SD = 2.96), p < 0.001). A cutoff SUV(max) value of 4.0 had high sensitivity and specificity of 1.0 and 0.94 to distinguish between PN and MPNST. FDG-PET can be helpful in predicting malignant transformation in children with plexiform neurofibromas and determining the need for biopsy and/or surgical resection.
Response of nuclear polyhedrosis virus-resistant Spodoptera frugiperda larvae to other pathogens and to chemical insecticides

Selection in the laboratory for Spodoptera frugiperda (Sf) resistant to nuclear polyhedrosis virus (NPV) affected the susceptibility of the insect to certain other mortality agents, including a chemical insecticide. Median lethal concentrations (LC50S) and associated statistics were compared for several mortality agents between colonies of NPV-resistant and -susceptible (control) insects. Compared to the susceptible insects, the NPV-resistant insects were cross-resistant to the S. frugiperda granulosis virus and to the Autographa californica NPV based on nonoverlap of 95% fiducial limits of the LC50S. The NPV-resistant insects were significantly more susceptible to methyl parathion than the control insects. The two colonies of S. frugiperda did not differ significantly in their response to Bacillus thuringiensis, Vairimorpha necatrix, or carbaryl. The cross-resistance experiments were based on per os exposure of the insects to the pathogens and insecticides; the susceptibility of the resistant and control insects did not differ significantly when the Sf NPV was injected into the hemocoel or when methyl parathion was applied topically.
The role of clinical pharmacology in supporting the emergency use authorization of an unapproved anti-influenza drug, peramivir.

On 23 October 2009, the commissioner of the US Food and Drug Administration (FDA) issued an Emergency Use Authorization (EUA) for peramivir for intravenous injection, an unapproved neuraminidase inhibitor used for treating certain hospitalized adult and pediatric patients infected with 2009 H1N1 influenza. This was the first EUA of an unapproved drug product. This report summarizes the critical contributions of the clinical pharmacology review team in support of the peramivir EUA. Clinical Pharmacology & Therapeutics (2010) 88 5, 587–589. doi: 10.1038/clpt.2010.187
Reversible carbon monoxide photodissociation from Cu(I) coordination compounds

Pulsed light excitation of [CuI(TMPA)(CO)]+ in organic solvents at room-temperature results in rapid, k > 108 s-1, release of carbon monoxide to yield the solvento complex, [CuI(TMPA)(S)]+. The dynamics of this process and the subsequent rebinding of CO were quantified by time-resolved UV−vis and IR spectroscopies. This report represents the first examples of CO photodissociation from copper coordination compounds and an unusual reactivity of metal-to-ligand charge-transfer excited states.
Transition in Romania: Is joining the European Union a win for all?

Romania joined the European Union (EU) on January 1, 2007 with promises of great economic gains for all Romanians. This research comprised from 462 Romania respondents shows that in the short run, there are groups who do not see benefits. Depth interviews and survey data show that both peasants and older Romanians have a much more pessimistic outlook for Romania's economic future as a member of the EU, and that EU entry is an unwelcome change in selling patterns for Romania's suppliers of local goods.
Be All That You Can Be?: Racial Identity Production in the U.S. Military

This analysis applies concepts from Stratification Economics to undertake an empirical investigation of racial identity production in the U.S. military. The theoretical model treats racial identity as a Becker-type commodity produced by combining market goods and services, and time, using a technology based on pre-existing cultural knowledge. The model is estimated using data from the 1996 Armed Forces Equal Opportunity Survey. The findings suggest that pre-military constructions of racial identity and patterns of racial interaction significantly constrain efforts to inculcate an identification with military culture that sublimates the sources of racial conflict. To the extent that racial tensions deteriorate in the civilian sector it is likely that the challenges facing the military in fostering unit cohesion will intensify. Existing interventions designed to promote military identity and diffuse sources of racial tension appear to have limited efficacy.
Determination of proanthocyanidins in grape products by liquid chromatography/mass spectrometric detection under low collision energy.

A method has been established for the identification of proanthocyanidins and quantification of individual monoproanthocyanidins using liquid chromatography/electrospray ionization-mass spectrometric detection (LC/ESI-MSD) for raw grape products. The separated monoproanthocyanidins and oligoproanthocyanidins were individually analyzed and identified by their molecular ion peaks using LC/MS. Using HPLC/ESI-MSD, the proanthocyanidin monomers, (+)-catechin (C), (−)-epicatechin (EC), (−)-catechin gallate (CG), and (−)-epicatechin gallate (ECG) in grape products were successfully quantified by LC/MS/MS detection of protonated molecular ions and characteristic fragment ions for each component under the optimized low collision energy level of 20%. For the investigated concentration ranges of C (21.88−11 200 ng/mL), EC (21.10−10 800 ng/mL), CG (36.72−18 800 ng/mL), and ECG (39.84−20 400 ng/mL), good linearities (r2 > 0.99) for standard curves were obtained. Validation of this method showed an accuracy that was we...
Fatty acid synthesis in African trypanosomes: a solution to the myristate mystery

The glycosyl phosphatidylinositol anchor of the trypanosome variant surface glycoprotein contains myristate as its sole fatty acid component. Surprisingly, there does not appear to be enough myristate in either the parasite or its host's bloodstream to sustain myristoylation of the enormous quantity of variant surface glycoprotein produced. Here, we discuss how the trypanosome solves its myristate dilemma. The parasite not only efficiently salvages and processes myristate from the bloodstream, but it also makes myristate de novo using a recently discovered specialized fatty acid synthesis system.
Health Risk Perceptions and Exercise in Older Adulthood An Application of Protection Motivation Theory

Protection Motivation Theory (PMT) was applied to explore the relationship between perceived risk of acute health crises and intent to exercise. Interviews of 351 community-living older adults asse...
Spectral Measurements Of Atmospheric OH And O 2 NIR Airglow With A Michelson FTS And InGaAs Detector

Recent developments and the integration of an InGaAs detector with a precision, compact Michelson interferometer have provided a very sensitive, reliable, and portable measurement tool for studying near infrared upper atmospheric emissions. Spectrically resolved and calibrated line intensity measurements of major portions of the Δν = 2 and the Δν = 3 band sequences of the OH Meinel airglow emissions are obtainable from ground based sites. Typically, the spectrometer provides signal-to-noise ratios of 50/1 in one minute measurement time. Time resolved rotational OH temperatures and therefore ambient temperatures corresponding to the 80 to 95 Km OH emission region can be obtained from the data. Also the metastable excited state (alAg) of the molecular 02 (0,0) band at 1.27 pm and the (0,1) band at 1.58 pm are measurable. It is even possible to observe the OH and 02 emissions during the twilight corresponding to sun illuminated conditions at the emission altitudes if spectral discrimination and background suppression techniques are applied to reduce the unwanted effects of scattered solar radiation. Thus, continuous measurements of the emissions can be performed during the daytime to nighttime transition and throughout the night.
One-dimensional supramolecular assemblies based on a Re2(III,III) synthon and their solid-state phosphorescence.

Reactions between Re2(DMBA)4(NO3)2 (1; DMBA is dimethylbenzamidinate) and a bidentate dianion, either tungstate (WO42-) or terephthalte (1,4-(O2C)2C6H42-), resulted in the one-dimensional coordination polymers [Re2(DMBA)4(μ-O,O‘-WO4)]∞ (2) and [Re2(DMBA)4(μ-O,O‘-1,4-(O2C)2C6H4)]∞ (3), respectively. Both polymers display phosphorescence from a 3(δ → δ*) state, which is significantly blue shifted from the phosphorescence previously observed for Re2(DMBA)4Cl2 type compounds.
Massive Empyema Due to Citrobacter Diversus

Citrobacter diversus is a gram-negative rod member of the Enterobacteriaceae family. A patient is described from whom this organism was isolated twice in pore culture from empyema fluid. Our isolates of Citrobacter diversus were resistant to ampicillin and carbenicillin and sensitive to cephalotbin. Citrobacter diversus should be distinguished from Citrobacter freundii, Enterobacter cloacae and Klebsiella pneumoniae. This organism joins Streptococcus pyogenes, bacteroides species, anaerobic streptococci and Escherichia coli as a cause of slight pneumonia with extensive empyema.
Direct evidence for selective modulation of psbA, rpoA, rbcL and 16S RNA stability during barley chloroplast development.

The turnover of RNAs encoded by seven different barley chloroplast genes was analyzed after treatment of barley shoots with tagetitoxin, a selective inhibitor of chloroplast transcription. Changes in RNA stability were examined during chloroplast development using basal and apical leaf sections of 4.5-day-old dark-grown seedlings and apical leaf sections of 4.0-day-old dark-grown seedlings which had been illuminated for 12 h. Of the RNAs examined, a 2.6 kb unspliced precursor of tRNA(lys) exhibited the shortest half-life, which was estimated to be 3 h. The 16S rRNA and psbA mRNA had the longest estimated half-lives, which were greater than 40 h. Among mRNAs, half-lives were estimated to range from 6 h for psaA mRNA, to over 40 h for psbA mRNA. Therefore, barley chloroplast mRNAs have long half-lives relative to bacterial mRNAs. The stability of atpB mRNA and the unspliced precursor of tRNA-lys was not altered during chloroplast development, while the stability of psaA mRNA decreased 2-fold. In contrast, the stability of the 16S rRNA and mRNAs for rpoA, psbA and rbcL increased during chloroplast development. The stability of 16S rRNA increased markedly during chloroplast development in the dark and this increase was maintained in illuminated seedlings. The stability of rbcL mRNA increased 2.5-fold during chloroplast development in the dark, and then decreased 2-fold in chloroplasts of light-grown plants. The initial increase in rpoA and psbA mRNA stability was also light-independent, with total increases in stability of at least 5-fold. In the case of rpoA, the stability of 2 of the 13 polycistronic rpoA transcripts that were detected in dark-grown plants was selectively increased during chloroplast development. In conclusion, the stability of some transcripts is selectively increased and further modulated during chloroplast development in barley. We propose that the selective stabilization of chloroplast mRNAs, which occurred independent of light, is an indication that non-light regulated developmental signals are involved in barley chloroplast mRNA stability.
Direct and Real-Time Quantification of Tenofovir Release from pH-Sensitive Microparticles into Simulated Biological Fluids Using 1H Nuclear Magnetic Resonance

In vitro drug release evaluation is a very important step toward the quality control of nano- or micro-particular drug delivery systems. However, most quantitative techniques such as high-performance liquid chromatography requires a dialysis membrane to separate the released free drug from these delivery systems, thus are not capable of direct detection and real-time quantification of the drug release kinetics. This study describes, for the first time, a rapid, specific, and direct method for the real-time quantification of in vitro tenofovir (TNF) release from pH-sensitive microparticles using a Varian 400 MHz 1H nuclear magnetic resonance (1H-NMR) spectrometer. Various analytical performance parameters such as linearity, precision, accuracy, limit of quantification, limit of detection, and robustness were validated according to International Conference on Harmonization (ICH) guidelines. The in vitro release of TNF from microparticles in both simulated vaginal fluid (VFS) and the mixture of VFS and simulated semen fluid was monitored and quantified in real time using 1H-NMR. The capability of real-time quantification of in vitro drug release from microparticles not only provides a more accurate prediction of its biological behavior in vivo, but is also independent of potential interference from the dialysis membrane. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:1170–1177, 2014
Molecular dynamics simulations of reactions on metal surfaces: rate constants for selected diatomic dissociation reactions

Abstract We have employed our normalized bond index (NBI) potential energy function in molecular dynamics simulations of the dissociation of various isotopes of (a) O 2 on Ag(111), Au(111), Pt(111) and Ni(111), (b) S 2 on Ni(111), and (c) C 2 on Ni(111) surfaces for the purpose of computing the zero coverage limit Arrhenius reaction rate constants. For 16 O 2 on Pt(111) we repeated the rate constant calculations at a simulated coverage of 0.4, in order to compare our result with an experimental value that corresponds to a low but otherwise unknown coverage. Our computed rate constants for 16 O 2 dissociation on Pt(111) are: (a) for the zero coverage limit, k =5.42×10 12 s −1 exp{−1.1 kcal/mol/RT}, (b) for moderate coverage, k =7.43×10 11 s −1 exp{−5.8 kcal/mol/RT}. The experimentally determined rate constant 9×10 11 s −1 exp{−2.5 kcal/mol/RT} is bracketed by our calculated values. Our computed rate constants possess the general trend that the Arrhenius pre-exponentials decrease with increasing vibrational mass of the dissociating bond. Also, the Arrhenius pre-exponentials tend to decrease with decreasing atomic heat of adsorption. We emphasize that the Arrhenius activation barrier is an effective barrier that depends on several aspects of the system, and may not closely correspond with any single feature of the potential energy surface.
Research needs in magnetic separation

High gradient magnetic separation is a new technique which provides a practical means for separating weakly paramagnetic materials down to colloidal particle size on a large scale and at flow rates one hundred times faster than conventional filtration. It is based on the use of matrices of finely divided filamentary ferromagnetic material containing 95% void space, such as steel wool, subjected to strong magnetic fields generated bysophisticated magnets of a type not previously used for magnetic separation. HGMS was developed in the late sixties by MIT, Sala Magnetics and the Huber Company, and has been used since then for the purification of kaolin. The technique is of importance to the entire chemical and mineral industry, and in the treatment of water and sewage, but its application in other areas has been delayed by lack of interdisciplinary communication. What is needed at present is a better understanding of the mechanism of HGMS to permit a more scientific approach to future applications, and more inducement to the firms which are currently developing the next generation of hardware. Other approaches to magnetic separation also merit more serious attention, particularly those based on open gradient rather than matrix structures. New magnet technology developed in conjunction with HGMS and the advent of superconductivity make available field strengths, gradients and volumes at least an order of magnitude above those offered by the prior art. Such magnetic fields have potential value beyond their use in magnetic separation inasmuch as they are likely to affect the kinetics of many chemical reactions, very probably also those involved in the combustion process itself.
On the nature and origin of Harper-Dorn creep

Abstract The present investigation, in lhich the lol stress-creep behavior of several aluminum grades is examined in detail, provides nel information on the nature and origin of Harper-Dorn creep. By conducting very long-term creep tests, it is sholn that Harper-Dorn creep arises from a genuine creep process lhich results not only in steady-state creep but also in large creep strains of the order of 0.1–0.2. Holever, Harper-Dorn creep lill not be observed in large-grained aluminum unless the dislocation density in the annealed samples is lol (10 3 t -3 × 10 4 cm t -2 ); aluminum specimens, in the form of single and polycrystals, lith initial dislocation densities of 10 6 –10 7 cm t-2 did not exhibit Harper-Dorn creep lhen crept at very lol stresses. This substructural reluirement concerning the initial dislocation density implies that a large grain sile is a necessary but insufficient condition for the occurrence of Harper-Dorn creep in aluminum at lol stresses. lhile data on dislocation substructures developed during Harper-Dorn creep shol the absence of subgrains, they reveal clear evidence of cross-slip. On the basis of this evidence, it is suggested that the large strains of Harper-Dorn creep may be accounted for by multiplication of dislocations by cross-slip. This interpretation appears consistent lith the observation that the condition of lol dislocation densities reluired for the occurrence of Harper-Dorn creep is the same condition under lhich cross-slip becomes an effective and dominant multiplication process.
Bone vs. fat: Embryonic origin of progenitors determines response to androgen in adipocytes and osteoblasts

Although androgen is considered an anabolic hormone, the consequences of androgen receptor (AR) overexpression in skeletally-targeted AR-transgenic lines highlight the detrimental effect of enhanced androgen sensitivity on cortical bone quality. A compartment-specific anabolic response is observed only in male and not in female AR3.6-transgenic (tg) mice, with increased periosteal bone formation and calvarial thickening. To identify anabolic signaling cascades that have the potential to increase bone formation, qPCR array analysis was employed to define expression differences between AR3.6-tg and wild-type (WT) periosteal tissue. Notably, categories that were significantly different between the two genotypes included axonal guidance, CNS development and negative regulation of Wnt signaling with a node centered on stem cell pathways. Further, fine mapping of AR3.6-tg calvaria revealed that anabolic thickening in vivo is not uniform across the calvaria, occurring only in frontal and in not parietal bones. Multipotent fraction 1 progenitor populations from both genotypes were cultured separately as frontal bone neural crest stem-like cells (fNCSC) and parietal bone mesenchymal stem-like cells (pMSC). Both osteoblastic and adipogenic differentiation in these progenitor populations was influenced by embryonic lineage and by genotype. Adipogenesis was enhanced in WT fNCSC compared to pMSC, but transgenic cultures showed strong suppression of lipid accumulation only in fNCSC cells. Osteoblastogenesis was significantly increased in transgenic fNCSC cultures compared to WT, with elevated alkaline phosphatase (ALP) activity and induction of mineralization and nodule formation assessed by alizarin red and von Kossa staining. Osteocalcin (OC) and ALP mRNA levels were also increased in fNCSC cultures from AR3.6-tg vs. WT, but in pMSC cultures ALP mRNA levels, mineralization and nodule formation were decreased in AR3.6-tg cells. Expression differences identified by array in long bone periosteal tissue from AR3.6-tg vs. WT were recapitulated in the fNCSC samples while pMSC profiles reflected cortical expression. These observations reveal the opposing effects of androgen signaling on lineage commitment and osteoblast differentiation that is enhanced in cells derived from a neural crest origin but inhibited in cells derived from a mesodermal origin, consistent with in vivo compartment-specific responses to androgen. Combined, these results highlight the complex action of androgen in the body that is dependent on the embryonic lineage and developmental origin of the cell. Further, these data these data suggest that the periosteum surrounding long bone is derived from neural crest.
Mimic Jews and Jewish Mimics in Antiquity: A Non-Girardian Approach to Mimetic Rivalry

Girard may have been on to something when he attempted to trace religious violence back to a struggle between mimetic rivals, but the resulting theory has been rightly criticized for its indifference to the particulars of historical context. With help from post-colonial scholarship, this paper aims to rethink the concept of mimicry as used by scholars of religion by situating an example from ancient Judaism, Josephus's description of the Samaritans as hostile doubles of the Jews, in the particular cultural environment in which this ancient historian wrote. The author hopes to contribute to our understanding of the Samaritans, and of Josephus as a slippery double in his own right, but the essay's real point is to caution against any generalizing approach to mimicry by stressing it as an adaptive behavior, a tactic, whose motives and workings are best understood within the particular cultural habitat to which the mimic is responding.
Oxidative dissolution of metacinnabar (β-HgS) by dissolved oxygen

Abstract The oxidative dissolution rate of metacinnabar by dissolved O 2 was measured at pH ∼5 in batch and column reactors. In the batch reactors, the dissolution rate varied from 3.15 (±0.40) to 5.87 (±0.39) × 10 −2 μmol/m 2 /day (I=0.01 M, 23°C) and increased with stirring speed, a characteristic normally associated with a transport-controlled reaction. However, theoretical calculations, a measured activation energy of 77 (±8) kJ/mol (I=0.01 M), and the mineral dissolution literature indicate reaction rates this slow are unlikely to be transport controlled. This phenomenon was attributed to the tendency of the hydrophobic source powder to aggregate and minimize the effective outer surface area. However, in a column experiment, the steady-state dissolution rate ranged from 1.34 (±0.11) to 2.27 (±0.11) x 10 −2 μmol/m 2 /day (I=0.01 M, 23°C) and was also influenced by flow rate, suggesting hydrodynamic conditions may influence weathering rates observed in the field. The rate of Hg release to solution, under a range of hydrogeochemical conditions that more closely approximated those in the subsurface, was 1 to 3 orders of magnitude lower than the dissolution rate due to the adsorption of released Hg(II) to the metacinnabar surface. The measured dissolution rates under all conditions were slow compared to the dissolution rates of minerals typically considered stable in the environment, and the adsorption of Hg(II) to the metacinnabar surface further lowered the Hg release rate.
Changes in Levels of Affirmative Action in College Admissions in Response to Statewide Bans and Judicial Rulings

Affirmative action in college admissions was effectively banned in Texas by the Hopwood ruling in 1997, by voter referenda in California and Washington in 1996 and 1998, and by administrative decisions in Florida in 1999. The Hopwood and Johnson rulings also had possible applicability to public colleges throughout Alabama, Georgia, Louisiana, and Mississippi. The Supreme Court’s 2003 decision in the Grutter and Gratz cases reaffirmed but limited the legal basis for affirmative action in colleges. This article uses nationally representative data on the admissions decisions of high school students in 1992 and 2004 to estimate the magnitude of the change in affirmative action in college admission decisions (i.e., how these policy changes affected the relative likelihood of admission of minority and nonminority applicants). We find substantial declines in levels of affirmative action practiced by highly selective colleges in the states affected by bans and the Hopwood and Johnson rulings, and no evidence of d...
Effect of uncertainty on the time course for selection of verbal name codes

Response selection takes time. Hick’s law (Hick, 1952) predicts that the time course of response selection is a logarithmic function of the number of equally likely response alternatives. However, recent work has shown that oculomotor responses constitute noteworthy exceptions in that the latencies of saccades (Kveraga, Boucher, & Hughes, 2002) and smooth pursuit movements (Berryhill, Kveraga, Boucher, & Hughes, 2004) are completely independent of response uncertainty. This finding extends to the case in which the required response was known in advance (i.e., simple reaction times [RTs] were equivalent to choice RTs). In view of these results, we reevaluated reports that latencies to name visually presented digits (Experiment 1) and/or repeat aurally presented digits (Experiment 2) are similarly independent of the size of the response set. We found that naming latencies were equivalent for response set sizes from one to eight, but simple RTs (response set of one) were faster. Thus, the overlearned task of digit naming is indeed highly automatic but has not reached the level of automaticity characteristic of the oculomotor system.
Linked jazz: an exploratory pilot

This paper reports on a pilot conducted within Linked Jazz, a project that investigates the potential of Linked Open Data (LOD) technology to enhance discovery and visibility of digital cultural heritage materials. The project explores the applicability of the Friend-Of-A-Friend (FOAF) ontology to digital archives of jazz history to expose relationships among musicians and reveal their community's network. Finding innovative ways of connecting cultural data and making them searchable in an open discovery environment generates unprecedented opportunities to create new meaning and elicit new streams of interpretation. The project consists of multiple phases and is intended to progress in an iterative and experimental way. The first step was to pilot a method to create a dataset of RDF triples representing jazz artists and their social connections.
REORGANIZING COLLECTION DEVELOPMENT AND ACQUISITIONS IN A MEDIUM-SIZED ACADEMIC LIBRARY

The University of Dayton Roesch Library reorganized the collection development and acquisitions departments during 1995 and 1996 in order to improve the collection and make the process of acquiring materials more responsive to the needs of students and faculty. The old organization was department-based, with teaching faculty controlling most of the materials budget. The Associate Director for Technical Services coordinated the funds and supervised acquisitions staff. Perceived imbalances in the collection, student and faculty dissatisfaction with the process, and the desire for public services librarians to have greater influence in collection decisions led to a major reorganization. The new model distributes budget authority among all librarians based on subjects rather than academic departments. It empowers librarians to make purchasing and weeding decisions within their subject areas. Book and periodical acquisitions are combined into a single support unit that reports to the Coordinator and Head of Collection Management. The new organization has streamlined acquisitions processes to make ordering simpler, and the time between ordering and receipt has been shortened. The new model shifts the emphasis from process to service.
Vitamin A equivalence of the β-carotene in β-carotene–biofortified maize porridge consumed by women?

Background: b-Carotene–biofortified maize is being developed through plant breeding as a sustainable agronomic approach to alleviate vitamin A deficiency. Objective: Our objective was to quantify the vitamin A equivalence of the b-carotene in b-carotene–biofortified maize based on consumption of a single serving of maize porridge. Design: Six healthy women each consumed three 250-g portions of maize porridge as follows: 1) b-carotene–biofortified maize porridge containing 527 lg (0.98 lmol) total b-carotene, 2) white maize porridge with a b-carotene reference dose containing 595 lg (1.11 lmol) added b-carotene, and 3) white maize porridge with a vitamin A reference dose containing 286 lg retinol activity equivelent (1.00 lmol) added retinyl palmitate. Each portion contained 8.0 g added sunflower oil. The porridges were consumed in random order separated by � 2 wk. Blood samples were collected over 9 h. Retinyl palmitate was analyzed in plasma triacylglycerol–rich lipoprotein (TRL) fractions by HPLC with coulometric array electrochemical detection. Results: Mean (6SD) areas under the curve for retinyl palmitate in
A wetting and drying scheme for POM

In shallow-water models, wetting and drying (WAD) are determined by the total water depth D ¼ 0 for 'dry' and >0 for 'wet'. Checks are applied to decide the fate of each cell during model integration. It is shown that with bottom friction values commonly used in coastal models, the shallow-water system may be cast into a Burger's type equation for D. For flows dominated by D (i.e. jrD jj r H j, where H ðx; yÞ defines topography) a non-linear diffusion equation results, with an effective diffusivity that varies like D 2 , so that 'dry' cells are regions where 'diffusion' is very small. In this case, the system admits D ¼ 0 as part of its continuous solution and no checks are necessary. For general topography, and/or in the case of strong momentum advection, 'wave-breaking' solution (i.e. hydraulic jumps and/or bores) can develop. A WAD scheme is proposed and applied to the Princeton Ocean Model (POM). The scheme defines 'dry' cells as regions with a thin film of fluid O (cm). The primitive equations are solved in the thin film as well as in other regular wet cells. The scheme requires only flux-blocking conditions across cells' interfaces when wet cells become dry, while 'dry' cells are temporarily dormant and are dynamically activated through mass and momentum conservation. The scheme is verified against the above-mentioned diffusion and Burger's type equations, and tested also for one and two-dimensional channel flows that contain hydraulic jumps, including a laboratory dam-break problem. 2004 Published by Elsevier Ltd.