cssi/SciSciGPT-SciSciNet huggingface dataset:
Sharp silicon/lead zirconate titanate interfaces by electrophoretic deposition on bare silicon wafers and post-deposition sintering

Abstract Thick films of Nb-doped lead zirconate titanate (PZT) on bare silicon (Si) wafers were prepared by electrophoretic deposition (EPD) in ethanol-based suspensions. Alloyed Al/Si ohmic contacts were used for electrical connections. EPD on bare Si wafers was obtained with similar results to metallic substrates, at nominal electric fields between 4350 and 10900 V m −1 . Well-adhered and crack-free green films were obtained after solvent evaporation. Sintering of green PZT films was performed at either 850 °C or 950 °C for 1 h. Sintered PZT films on Si featured sharp Si/PZT interfaces and a good degree of crystallinity. Possible applications of sintered PZT/Si structures as on-chip sensors are discussed, taking into account relevant literature results.
Threshold stress creep behaviour in Ta

Abstract The details of creep and substructure in powder metallurgy Ta were investigated in the temperature range 1523–1623 K and at stresses extending from 35 to 120 MPa. The experimental data show that the apparent creep behaviour of Ta is different from that of pure metals with regard to two characteristics: the stress exponent is about 7 and the activation energy for creep (502kJ mol−1) higher than that for self-diffusion (416.5kJ mol−1). An analysis of the data reveals a threshold stress for creep, which strongly depends on temperature. An examination of creep substructure by means of transmission electron microscopy shows the presence of frequent interactions between dislocations and nanometre particles in the interiors of equiaxed subgrains whose average size decreases with increasing stress. The dislocation-dispersion particle interaction configurations resemble those reported for dispersion-strengthened alloys. It is suggested that these particles were introduced in Ta as a result of its processi...
Oxidation of 3,4-dihydroxyphenylacetaldehyde, a toxic dopaminergic metabolite, to a semiquinone radical and an ortho-quinone

The oxidation and toxicity of dopamine is believed to contribute to the selective neurodegeneration associated with Parkinson disease. The formation of reactive radicals and quinones greatly contributes to dopaminergic toxicity through a variety of mechanisms. The physiological metabolism of dopamine to 3,4-dihydroxyphenylacetaldehyde (DOPAL) via monoamine oxidase significantly increases its toxicity. To more adequately explain this enhanced toxicity, we hypothesized that DOPAL is capable of forming radical and quinone species upon oxidation. Here, two unique oxidation products of DOPAL are identified. Several different oxidation methods gave rise to a transient DOPAL semiquinone radical, which was characterized by electron paramagnetic resonance spectroscopy. NMR identified the second oxidation product of DOPAL as the ortho-quinone. Also, carbonyl hydration of DOPAL in aqueous media was evident via NMR. Interestingly, the DOPAL quinone exists exclusively in the hydrated form. Furthermore, the enzymatic and chemical oxidation of DOPAL greatly enhance protein cross-linking, whereas auto-oxidation results in the production of superoxide. Also, DOPAL was shown to be susceptible to oxidation by cyclooxygenase-2 (COX-2). The involvement of this physiologically relevant enzyme in both oxidative stress and Parkinson disease underscores the potential importance of DOPAL in the pathogenesis of this condition.
A Comparison of Structures and Crystallization Behavior of Gels, Gel-Derived Classes and Conventional Glasses

Studies on the structures and crystallization behavior of gels in TiO 2 , GeO 2 , SiO 2 -GeO 2 and PbO-GeO 2 systems are presented to analyze the differences in structures and crystallization behavior of gel-derived glasses and conventional glasses. The kinetic parameters for crystallization such as activation energies and frequency factors of gels, gel-derived glasses and conventional glasses in the GeO 2 -PbO system are presented to elucidate their difference in nucleation and crystallization behaviors. The influence of gel processing parameters such as pH and water concentration on the crystallization behavior of gels are discussed.
Anomalous multiplet-splitting intensity ratios in K -level x-ray photoemission spectra of NO and O 2

The intensity ratios of the multiplet-split $\mathrm{N}1s$ peak of NO and $\mathrm{O}1s$ peak of ${\mathrm{O}}_{2}$ in the x-ray photoemission spectra of these paramagnetic molecules were found to exceed the simple multiplet ratios $\frac{(S+1)}{S}$. Hartree-Fock calculations were performed on the ground state and the $1s$-hole states in each case, and total overlap probabilities for the passive orbitals were computed. Positive deviations from the multiplet ratios were obtained, but they were smaller than the experimental deviations. The $\mathrm{NO}(\mathrm{N}\stackrel{-}{1s},\frac{^{3}\ensuremath{\Pi}}{^{1}\ensuremath{\Pi}})$ ratios were 3.43 (8) (expt.), 3.09 (calc.), and 3 (multiplet), while for ${\mathrm{O}}_{2}(\mathrm{O}\stackrel{-}{1s},\frac{^{4}\ensuremath{\Sigma}}{^{2}\ensuremath{\Sigma}})$ the ratios were 2.47(3) (expt.), 2.28 (calc.), and 2 (multiplet). Thus incomplete overlap accounts for some, but not all, of the observed deviation. Another consequence of incomplete overlap is multiple excitation during photoemission. The total probabilities for multiple excitation were computed as $0.25(\mathrm{NO},\mathrm{N}\stackrel{-}{1s})$, $0.28(\mathrm{NO},\mathrm{O}\stackrel{-}{1s})$, and $0.42({\mathrm{O}}_{2},\mathrm{O}\stackrel{-}{1s})$, in agreement with the observation by Carlson et al. of large multiple-excitation probabilities.
Intracardiac Echocardiography to Guide Transseptal Left Heart Catheterization for Radiofrequency Catheter Ablation

Transseptal Catheterization. Introduction: The purpose of this study was to asess the feasibility and safety of intracardiac echocardiography to guide transseptal puncture for radiofrequency catheter ablation. Methods and Results: Transcatheter intracardiac echocardiography (9 MHz) was utilized to guide transseptal puncture in 53 patients undergoing radiofrequency catheter ablation. The anatomy and relationship of intra- and extracardiac structures were visualized with the ultrasound transducer positioned at the fossa ovalis. The tip of the transseptal dilator and tenting of the fossa ovalis and the left atrial wall were simultaneously visualized in a single ultrasound image in all patients. With maximum tenting of the fossa ovalis, the mean distance from the fossa to the left atrial wall was 11.9 ± 5.8 mm (range: 1.8 to 25.6 mm). In four patients (8%), the tented fossa ovalis abutted the left atrial wall and the transseptal dilator was redirected with ultrasound guidance. Puncture of the interatrial septum was achieved through the fossa ovalis in each patient and required a single attempt in 51 patients (96%). The mean number of punctures per patient was 1.1 ± 0.4. The mean time to perform transseptal catheterization was 18.2 ± 6.8 minutes. There were no complications. Conclusion: Intracardiac echocardiography delineated the anatomy of intra- and extracardiac structures not identified with fluoroscopy and simplified correct positioning of the transseptal dilator, puncture of the fossa ovalis, and cannulation of the left atrium in a timely and uncomplicated fashion.
Molecular Modeling of Two Distinct Triangular Oligomers in Amyloid β-protein

Amyloid-β (Aβ) peptides exhibit many distinct structural morphology at the early aggregate stage, some of which are biological relevant to the pathogenesis of Alzheimer’s disease (AD). Atomic-resolution structures of the early Aβ aggregates and their conformational changes in amyloid aggregation remain elusive. Here, we perform all-atom molecular modeling and dynamics simulations to obtain two stable triangular-like Aβ structures with the lowest packing energy, one corresponding to the Tycko’s model (Paravastu, A.; Leapman, R.; Yau, W.; Tycko, R. Proc. Nat. Acad. Soc. U.S.A. 2008, 105, 18349−18354) (referred to C-WT model) and the other corresponding to computational model (N-WT model). Both models have the same 3-fold symmetry but distinct β-sheet organizations in which three Aβ hexamers pack together via either C-terminal β-strand residues or N-terminal β-strand residues forming distinct hydrophobic cross section. Structural and energetic comparisons of two 3-fold Aβ oligomers, coupled with structural c...
Comet b 1881

THE comet at present visible was examined by me with the spectroscope on the 8¼-inch refractor on Saturday evening, August 27. The three principal hydrocarbon bands were plainly visible, the central one being the brightest, and on comparing them with the spectrum of a spirit-lamp flame the coincidence of the least refrangible sides of the bands in the two spectra was sensibly complete. The nucleus gave a narrow continuous spectrum, and I could see no trace of such a spectrum except from that point. I could see no other band in the spectrum except the three above mentioned, but the proximity of the comet to the horizon may have something to do with this.
Prolactin Metabolic Clearance and Resistance to Dopaminergic Suppression in Acute Uremia

A nephrectomized rat model was developed to examine PRL resistance to dopaminergic suppression, which is frequently present in humans with renal insufficiency. The MCR and the response of PRL to a dopamine (DA) infusion (0.4 microgram/kg . min) were measured in 24-h totally nephrectomized (TN) and sham-nephrectomized (SN) rats concurrently treated with alpha-methyl-p-tyrosine (AMPT), an inhibitor of DA synthesis. TN rats became significantly hyperprolactinemic within 1 day [36.2 +/- 7.1 vs. 18.5 +/- 2.5 (+/- SE) ng/ml; P less than 0.05]. SN and TN rats responded to AMPT with significant and sustained 3- and 5.5-fold increases in PRL, which DA reduced by 85% and 24%, respectively. Total nephrectomy decreased the PRL MCR by 58% (TN, 0.51 +/- 0.03; SN, 1.22 +/- 0.13 ml/min; P less than 0.001) and significantly increased the PRL secretion rate (TN, 79 +/- 10; SN, 37 +/- 8 ng/min; P less than 0.01). In the absence of DA infusion, AMPT reduced plasma DA to undetectable levels, while the median eminence DA contents in TN and SN rats were reduced to similar levels. Our data suggest that the totally nephrectomized rat is a suitable model to study PRL resistance to dopaminergic suppression, and that because DA does not cross the blood-brain barrier, the defect in uremia probably occurs at the level of the lactotroph.
Relation between the defense mechanisms inventory and the coping operations preference enquiry.

The present study was conducted to estimate the association of the scores on the subscales of the Defense Mechanisms Inventory to the Denial Score on the COPE for 91 volunteers who were undergraduates and 7 graduate students. There were 31 men and 67 women; 77 were white and 21 were nonwhite. Both inventories were administered in a group format. The intercorrelations of COPE—Denial and subscales of the Defense Mechanisms Inventory did not approach significance; this supports the Haan/Kroeber hypothesis suggesting that a qualitative difference be made between coping and defensiveness and the Lazarus/French hypothesis suggesting a dichotomy of “problem-focused” coping and “emotion-focused” coping.
Resonance Raman spectra

Selection rules for resonance Raman spectra are given for several porphins of D 4h point group symmetry. A normal coordinate treatment is presented, based on a potential function for which stretching and bending force constants are related to bond lengths, and to the product of the bond lengths of the bonds defining the bending angle, respectively. The results can be correlated with the persistent frequencies observed in the resonance Raman spectra of haem proteins where the haem is an iron octasubstituted porphin.
Photon interferometry for heavy ion collisions

Abstract The Hanbury-Brown-Twiss correlation of high-energy photons emitted from heavy ion collisions is studied and it is found that both the polarization average and a possible coherent component complicate the extraction of the size and lifetime of the emitting source from the correlation function.
Dynamic mechanical properties of poly-n-hexyl methacrylate

Abstract The real (J′) and imaginary (J″) components of the complex compliance have been measured between 15 and 2400 cycles/sec. in the temperature range from 5° to 125°C. for a fractionated poly-n-hexyl methacrylate with molecular weight 4.0 × 106. The method of reduced variables gave superposed curves for J′ and J″ except for the same two anomalies observed for poly-n-butyl methacrylate: the maximum in J″ increased slightly with increasing temperature, and near the bottom of the dispersion of J′ the data corresponded to two additive mechanisms with different temperature dependences. For the principal (α) mechanism, the temperature dependence of retardation times follows the WLF form with fg (relative free volume at the glass transition temperature, Tg) = 0.025 and αf (thermal expansion coefficient of free volume) = 1.9 × 10−4 deg.−1. For the β mechanism, the temperature dependence of retardation times corresponds to an apparent activation energy of 13 kcal. The retardation and relaxation spectra of the α mechanism resemble those for other methacrylate polymers, but certain progressive effects of increasing side-chain length on the position and detailed shape of the spectra are apparent. The logarithm of the monomeric friction coefficient (in dynes-sec./cm.) is −5.21 at 100°C. and 2.63 at −5°C. (Tg). At their respective Tg′s, the friction coefficients of polyethyl, poly-n-butyl, and poly-n-hexyl methacrylates are in the ratios 4000:13:1, though the relative free volume at Tg as deduced from the WLF equation is the same for all three polymers.
Introduced populations as genetic reservoirs for imperiled species: a case study of the Arkansas River Shiner (Notropis girardi)

The Arkansas River Shiner is a threatened species that has been extirpated throughout much of its native range (Arkansas River drainage) and remaining populations are imperiled. Prior to 1978, this species was accidently introduced to the Pecos River (Rio Grande drainage) via bait bucket, and has since persisted for over 30 years. Genetic data show that the Pecos River population maintains comparable levels of diversity at mitochondrial DNA and microsatellite loci relative to native range populations. Hence, we examined several factors that could be responsible for high introduced genetic diversity including (a) multiple introductions from genetically distinct sources (b) introduction of individuals from a genetically diverse source followed by rapid population expansion, (c) presence of life-history traits that foster propagule diversity and wide spatio-temporal demographic and genetic mixing; and (d) introduction to a suitable habitat in the non-native range. Our findings indicate Arkansas River Shiner was likely introduced from the Canadian River and subsequently experienced rapid population expansion that mitigated loss of diversity during the founding event. Threats to native Arkansas River Shiner have increased due to ongoing drought and water resource development, thus a finding of high diversity in the Pecos River suggests conservation significance of this non-native population. Further, it identifies the Pecos River as both a refuge for native endemic fishes and of genetic diversity of introduced, yet threatened, species.
Frames of reference for allocating attention to space: Evidence from the neglect syndrome

With respect to what frames of reference, or spatial coordinate systems, is attention allocated to locations in space? We posed this question about the spatial attention system that has been damaged in neglect patients, distinguishing among three possible types of spatial reference frame: viewer-centered, according to which locations are coded with respect to the viewer, environment-centered, according to which locations or coded with respect to the environment, and object-centered, according to which locations are coded with respect to an object. The three candidate frames of reference were decoupled from one another by rotating either the viewer or the stimulus object. Visual search performance suggested that the neglected hemifield was defined with respect to both viewer-centered and environment-centered frames of reference, but not with respect to an object-centered frame of reference. The role of objects in the allocation of attention to space, and the relation between our findings and the "two cortical visual systems" hypothesis, are discussed.
Design and construction of an evanescent optical wave device for the recanalization of vessels

Abstract Removing atherosclerotic material without transecting the vessel wall is a common problem for vascular surgeons and interventional cardiologists. The goal of this project is to design and construct a device that uses evanescent optical waves for precise, controlled laser ablation. For laser light incident at an angle to an optic–tissue interface greater than or equal to the critical angle, an evanescent optical wave is launched into the tissue. With evanescent optical waves, there is no free-beam propagation and the laser energy can be confined to a layer less than one wavelength thick at the optic–tissue interface. Several device designs have been proposed and constructed. The Duke University Mark III Infrared Free-Electron Laser is used to study energy deposition and ablation mechanisms at sapphire–tissue and zinc sulfide–tissue interfaces. Ablation experiments on human low-density lipoprotein and aorta tissue are presented.
Vector Polynomials and a Matrix Weight Associated to Dihedral Groups

The space of polynomials in two real variables with values in a 2-dimensional irreducible module of a dihedral group is studied as a standard module for Dunkl operators. The one-parameter case is considered, (omitting the two-parameter case for even dihedral groups). The matrix weight function for the Gaussian form is found explicitly by solving a boundary value problem, and then computing the normalizing constant. An orthogonal basis for the homogeneous harmonic polynomials is constructed. The coefficients of these polynomials are found to be balanced terminating 4F3-series.
Super-reflective color LCD with PDLC technology

— A novel reflective color LCD without polarizers has been developed using a PDLC film and a retro-reflector. Bright color images including moving images are achievable with ambient light. This novel LCD will enable the new application area of electronic paper.
Reducing operating time of a crawling robot for epicardial surgery

HeartLander is a small, mobile robot designed to assist with surgical procedures on the surface of the heart. It crawls within the pericardial sac surrounding the heart. The friction forces HeartLander experiences from the pericardium and the heartbeat reduce locomotion efficiency. We have developed an algorithm that creates a plan for reaching a set of treatment targets, while minimizing the time spent in locomotion. Results from simulation show improvement over a simple greedy technique.
Health Care in Rural Texas

The purpose of this article is to assess the quality of health and health care services available to rural Texans. Specifically, we seek to answer two related questions. First, do people living in rural areas of Texas generally suffer from poorer health than people living in urban Texas? One undoubtedly would think so, given frequent references to the low quality of personal services in general for rural America. Moreover, the persistence of the congressional Rural Health Care Caucus over the past two decades points to a rural health care crisis. Second, to what extent are these differences in health conditions explained by differences in access to health care enjoyed by people living in the two different regions? Access certainly appears to be the problem alluded to above. Rural people apparently lack physician care. In addition to providing answers to these questions, we also examine the difference in the health conditions and access to care enjoyed by minority and non-minority rural Texans. Is this a part of the rural health care problem given the high incidence of non-whites in rural Texas? If so this may be minority rather than rural neglect. We briefly conclude the article with some recommendations for improving the problems we identify.
Low sodium intake corrects abnormality in β‐receptor–mediated arterial vasodilation in patients with hypertension: Correlation with β‐receptor function in vitro

To determine the contribution of altered beta-receptor function in the vasculature to the increased peripheral vascular resistance seen in hypertension, the effects of intra-arterial infusions of isoproterenol and epinephrine on forearm blood flow were determined in 11 male normotensive subjects and 11 male hypertensive subjects during 10 and 250 mmol/day sodium diets. Increased sodium intake from 10 to 250 mmol produced contrasting effects in the hypertensive and normotensive subjects. In the hypertensive subjects, sensitivity to isoproterenol decreased when sodium intake increased (median effective dose increased from 39 [95% confidence limits, 30 to 50] to 70 [95% confidence limits, 42 to 116] ng/min, p less than 0.05). On the other hand, in the normotensive subjects increased sodium intake resulted in an increased sensitivity to isoproterenol induced vasodilation (median effective dose decreased from 52 [38 to 71] to 29 [22 to 38] ng/min, p less than 0.01). No change occurred in sensitivity to epinephrine or in the maximum vasodilatory response to ischemia during dietary changes. Changes in beta-receptors on lymphocyte membranes paralleled the changes seen in vascular sensitivity so that the proportion of receptors exhibiting high affinity for agonists, a reflection of receptor adenylate cyclase coupling, decreased in the hypertensive subjects from 38.0% +/- 3.8% when they were receiving 10 mmol/day sodium to 29.6% +/- 2.7% when they were receiving 250 mmol/day sodium (p less than 0.01). However, the proportion increased from 32.4% +/- 3.7% for normotensive subjects receiving 10 mmol/day sodium to 47.1% +/- 7.8% for normotensive subjects receiving 250 mmol/day sodium (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
Performance documentation of the Engineering Model 30 cm diameter Thruster

The results of extensive testing of two 30-cm ion thrusters which are virtually identical to the 900 series Engineering Model Thruster in an ongoing 15,000-hour life test are presented. Performance data for the nominal fullpower (2650 W) operating point; performance sensitivities to discharge voltage, discharge losses, accelerator voltage, and magnetic baffle current; and several power throttling techniques (maximum Isp, maximum thrust/power ratio, and two cases in between are included). Criteria for throttling are specified in terms of the screen power supply envelope, thruster operating limits, and control stability. In addition, reduced requirements for successful high voltage recycles are presented.
Leadership development and self‐development: an empirical study

This paper explores, theoretically and empirically, some relationships between self‐development and leadership development. A theory about consciousness and leadership practices will be presented drawing from both modern science and the oldest texts on consciousness, the Vedas. Empirically, in a small, preliminary eight‐month pretest‐posttest control group study in one company, 24 subjects who learned a standard self‐development technique, Maharishi’s Transcendental Meditation, grew more in their expression of leadership behaviors, measured by the Leadership Practices Inventory, and expressed in individual and group interviews (0.05 and 0.01 significance).
A new aggregation technique for the solution of large systems of algebraic equations (IC simulation)

The term aggregation denotes a class of methods that were originally conceived as a way to compute an approximate solution of a linear system of equations. It has been shown that they could be used to accelerate the convergence of linear relaxation algorithms. Although all aggregation methods rely on the same general idea, each individual method is usually based on a heuristic that is valid for a particular class of problems. It is shown how the idea behind these methods can be generalized to include nonlinear equations, and a number of theorems concerning their theoretical properties are proven. How their performance in the linear case can be significantly improved if the heuristic approach is abandoned in favor of a rigorously mathematical one is shown. As a practical test, numerical results obtained on a number of matrices resulting from common problems in computer-aided design of integrated circuits are presented. >
Gauge Principles, Gauge Arguments and the Logic of Nature

Abstract I consider the question of how literally one can construe the “gauge argument,” which is the canonical means of understanding the putatively central import of local gauge symmetry principles for fundamental physics. As I argue, the gauge argument must be afforded (at best) a heuristic reading. Claims to the effect that the argument reflects a deep “logic of nature” must, for numerous reasons I discuss, be taken with a grain of salt.
Effect of hydrogen addition on criteria and greenhouse gas emissions for a marine diesel engine

Abstract Hydrogen remains an attractive alternative fuel to petroleum and a number of investigators claim that adding hydrogen to the air intake manifold of a diesel engine will reduce criteria emissions and diesel fuel consumption. Such claims are appealing when trying to simultaneously reduce petroleum consumption, greenhouse gases and criteria pollutants. The goal of this research was to measure the change in criteria emissions (CO, NO x , and PM 2.5 ) and greenhouse gases such as carbon dioxide (CO 2 ), using standard test methods for a wide range of hydrogen addition rates. A two-stroke Detroit Diesel Corporation 12V-71TI marine diesel engine was mounted on an engine dynamometer and tested at three out of the four loads specified in the ISO 8178-4 E3 emission test cycle and at idle. The engine operated on CARB ultra-low sulfur #2 diesel with hydrogen added at flow rates of 0, 22 and 220 SLPM. As compared with the base case without hydrogen, measurements showed that hydrogen injection at 22 and 220 SLPM had negligible influence on the overall carbon dioxide specific emission, EF CO 2 . However, in examining data at each load the data revealed that at idle EF CO 2 was reduced by 21% at 22 SLPM (6.9% of the added fuel energy was from hydrogen) and 37.3% at 220 SLPM (103.1% of the added fuel energy was from hydrogen). At all other loads, the influence of added hydrogen was insignificant. Specific emissions for nitrogen oxides, EF NO x , and fine particulate matters, EF PM 2.5 , showed a trade-off relationship at idle. At idle, EF NO x was reduced by 28% and 41% with increasing hydrogen flow rates, whilst EF PM 2.5 increased by 41% and 86% respectively. For other engine loads, EF NO x and EF PM 2.5 did not change significantly with varying hydrogen flow rates. One of the main reasons for the greater impact of hydrogen at idle is that the contribution of hydrogen to the total fuel energy is much higher at idle as compared to the other loads. The final examination in this paper was the system energy balance when hydrogen is produced by an on-board electrolysis unit. An analysis at 75% engine load showed that hydrogen production increased the overall equivalent fuel consumption by 2.6% at 22 SLPM and 17.7% at 220 SLPM.
The rate of vaporization of water and ice

Abstract The condensation coefficient, α, for water near 0°C and 43°C was mesaured using the technique of vaporization into a closed system and was found to be 0·042 and 0·027 respectively. The values of α for water obtained in the work are compared with previous measurements at 15°C and 100°C. The data indicate an exponential dependence of α on temperature with an activation energy of −1520 cal/g mole. The experimental results give a temperature dependence for α in agreement with recent work reported on solids but not clearly indicated by calculations according to the free angle ratio theory. The condensation coefficient is discussed in terms of the rate of escape of liquid water molecules, as estimated from the rate of rotation, compared to the rate of impingement of gaseous water molecules at the liquid surface. The values of α calculated according to this model are 0·035 at 0°C and 0·034 at 100°C, compared to the experimental values of 0·042 near 0°C and 0·02 at 100°C. The condensation coefficient for ice between −13°C and −2°C was found to be 0·0144, in contrast to values near unity measured below −40°C by others.
Characterization of unsaturated fatty acids by gas-liquid chromatography

The equivalent chain length (ECL) has been determined on 79 methyl esters of unsaturated fatty acids and on 7 ethyl esters by gas chromatography. Ethylene glycol succinate (EGS), diethylene glycol succinate, β-cyclodextrin acetate and Apiezon L were chosen as the liquid phases to be used. For methyl esters of mono- and polyenoic acids, the differences between ECL on EGS and ECL on Apiezon L approximate 0.84 per double bond. For positional isomers, the ECL on both EGS and Apiezon L are usually greater for the isomer having the longer proximal end of the molecule (smallest ω value). In these terms a triple bond is approximately equal to three double bonds. Esters of nonconjugated dienoic and trienoic acids of the same chain length are not separable on Apiezon L if their proximal structures are the same. This also applies to tetraenoic and pentaenoic acids of the same chain length and the same proximal structure. Conjugation of double bonds, either with the ester carbonyl group or with themselves, yields ECL values on Apiezon L greater than the number of carbon atoms in the acid. Monounsaturated and nonconjugated polyunsaturated esters have ECL values on Apiezon L lower than the number of carbon atoms of the acid. The ECL values of ethyl esters of 18 and 20 carbon acids are greater than the corresponding methyl esters on Apiezon L.
727-5 Differential Role of Circulating and Ventricular ANP as a Marker for Cardiac Filling Pressures and Ventricular Remodeling in a Model of Pacing Induced Heart Failure and Cardiac Hypertrophy

Previous studies have suggested that circulating atrial natriuretic peptide (ANP) is a marker for cardiac filling pressures and ventricular myocardial production of ANP a marker for ventricular hypertrophy and/or dilatation. To address the role of circulating ANP as a marker for ventricular hypertrophy and dilatation as compared to cardiac filling pressures, we developed a new canine model of pacing induced heart failure that in contrast to previous pacing models produces sustained ventricular hypertrophy. This involves gradually increasing the pacing rate from 180 to 240 bpm over 30 days (PROG PACE, n = 5) followed by 4 weeks of recovery (REC, n = 6). Four NORMAL dogs served as controls. Diastolic dimension (LVEDd) and EF were assessed by echo. LV mass was assessed by echo prior to rapid ventricular pacing (pre-RVP) in the PROG PACE (4.2 ± 0.2 g/kg) and REC (4.7 ± 0.2 g/kg) dogs. LV mass was assessed at autopsy after PROG PACE and REC and in NORMAL dogs. Ventricular ANP was assessed by sensitive and specific immunohistochemical staining for ANP 1–28. NORMAL PROG PACE REC LVEDd (mm) 39 ± 2 50 ± l *† 49 ± l*† EF(%) 49 ± 5 21 ± 3 *† 37 ± 2 *† PCWP(mmHg) 2.3 ± 0.6 21.5 ± 3.8 * 7.5 ± 0.9 *# CO (Llmin) 3.13 ± 0.18 1.47 ± 0.23 * 3.58 ± 0.34 # LV mass (g/kg) 4.6 ± 0.3 5.4 ± 0.3 † 55 ± 0.2 † ANP(pg/mL) 46 ± 8 181 ± 59 * 68 ± 15 * = p l 0.05 vs NORMAL. † = p l 0.05 vs pre-RVP. # = P l 0.05 vs PROG PACE. Immunohistochemistry was markedly positive for ANP in ventricular myocardium in both PROG PACE and REC dogs. Immunostaining of NORMAL ventricular myocardium was negative. These studies confirm that circulating ANP more closely parallels changes in cardiac filling pressures as compared to cardiac dilatation and/or ventricular hypertrophy. In contrast local ventricular ANP emerges as a sensitive local tissue marker for ventricular hypertrophy and dilatation in this novel model of heart failure and ventricular remodeling.
Comparative effectiveness of donation after cardiac death versus donation after brain death liver transplantation: Recognizing who can benefit.

Due to organ scarcity and wait-list mortality, transplantation of donation after cardiac death (DCD) livers has increased. However, the group of patients benefiting from DCD liver transplantation is unknown. We studied the comparative effectiveness of DCD versus donation after brain death (DBD) liver transplantation. A Markov model was constructed to compare undergoing DCD transplantation with remaining on the wait-list until death or DBD liver transplantation. Differences in life years, quality-adjusted life years (QALYs), and costs according to candidate Model for End-Stage Liver Disease (MELD) score were considered. A separate model for hepatocellular carcinoma (HCC) patients with and without MELD exception points was constructed. For patients with a MELD score $2,000,000/QALY. Patients with MELD scores of 21 to 30 (0.25 QALYs) and >30 (0.83 QALYs) also benefited from DCD transplantation with ICERs of $478,222/QALY and $120,144/QALY, respectively. Sensitivity analyses demonstrated stable results for MELD scores 20, but the preferred strategy for the MELD 15 to 20 category was uncertain. DCD transplantation was associated with increased costs and reduced survival for HCC patients with exception points but led to improved survival (0.26 QALYs) at a cost of $392,067/QALY for patients without exception points. In conclusion, DCD liver transplantation results in inferior survival for patients with a MELD score 20 and to HCC patients without MELD exception points.
Thirty Years of Performance of an Active Solar Space Heating/DHW System

A solar house in Knoxville, Tennessee has been operating for thirty years providing space heating and domestic hot water. The active system with air collectors and rock storage and heat pump back up has required minimal maintenance. Using data from sub-meters, the auxiliary and operating energy have been compared for the first three years of operation and the last eight years. There appears to be little or no degradation in performance during the thirty-year period.© 2009 ASME
Immigrant Civic Engagement: New Translations

On virtually a daily basis, American news media feature stories about immigrants. Many of these stories touch on questions about the balance between immigrants' civil rights and responsibilities, t...
Null mutation of the β2 nicotinic acetylcholine receptor subunit attenuates nicotine withdrawal-induced anhedonia in mice.

Abstract The anhedonic signs of nicotine withdrawal are predictive of smoking relapse rates in humans. Identification of the neurobiological substrates that mediate anhedonia will provide insights into the genetic variations that underlie individual responses to smoking cessation and relapse. The present study assessed the role of β2 nicotinic acetylcholine receptor (nACh receptor) subunits in nicotine withdrawal-induced anhedonia using β2 nACh receptor subunit knockout (β2−/−) and wildtype (β2+/+) mice. Anhedonia was assessed with brain reward thresholds, defined as the current intensity that supports operant behavior in the discrete-trial current-intensity intracranial self-stimulation procedure. Nicotine was delivered chronically through osmotic minipumps for 28 days (40 mg/kg/day, base), and withdrawal was induced by either administering the broad-spectrum nicotinic receptor antagonist mecamylamine (i.e., antagonist-precipitated withdrawal) in mice chronically treated with nicotine or terminating chronic nicotine administration (i.e., spontaneous withdrawal). Mecamylamine (6 mg/kg, salt) significantly elevated brain reward thresholds in nicotine-treated β2+/+ mice compared with saline-treated β2+/+ mice and nicotine-treated β2−/− mice. Spontaneous nicotine withdrawal similarly resulted in significant elevations in thresholds in nicotine-withdrawing β2+/+ mice compared with saline-treated β2+/+ and nicotine-treated β2−/− mice, which remained at baseline levels. These results showed that precipitated and spontaneous nicotine withdrawal-induced anhedonia was attenuated in β2−/− mice. The reduced expression of anhedonic signs during nicotine withdrawal in β2−/− mice may have resulted from the lack of neuroadaptations in β2 nACh receptor subunit expression and function that may have occurred during either nicotine exposure or nicotine withdrawal in wildtype mice. In conclusion, individuals with genetic variations that result in diminished function of the β2 nACh receptor subunit may experience less anhedonia during nicotine withdrawal, which may facilitate smoking cessation.
The impact of obesity on sepsis mortality: a retrospective review

Recent sepsis guidelines have focused on the early identification and risk stratification of patients on presentation. Obesity is associated with alterations in multiple inflammatory regulators similar to changes seen in sepsis, suggesting a potential interaction between the presence of obesity and the severity of illness in sepsis. We performed a retrospective chart review of patients admitted with a primary billing diagnosis of sepsis at a single United States university hospital from 2007 to 2010. Seven hundred and ninety-two charts were identified meeting inclusion criteria. Obesity was defined as a body mass index (BMI) ≥ 30 kg/m2. The data recorded included age, race, sex, vital signs, laboratory values, length of stay, comorbidities, weight, height, and survival to discharge. A modified APACHE II score was calculated to estimate disease severity. The primary outcome variable was inpatient mortality. Survivors had higher average BMI than nonsurvivors (27.6 vs. 26.3 kg/m2, p = 0.03) in unadjusted analysis. Severity of illness and comorbid conditions including cancer were similar across BMI categories. Increased incidence of diabetes mellitus type 2 was associated with increasing BMI (p < 0.01) and was associated with decreased mortality, with an odds ratio of 0.53 compared with nondiabetic patients. After adjusting for age, gender, race, severity of illness, length of stay, and comorbid conditions, the trend of decreased mortality for increased BMI was no longer statistically significant, however diabetes continued to be strongly protective (odds ratio 0.52, p = 0.03). This retrospective analysis suggests obesity may be protective against mortality in septic inpatients. The protective effect of obesity may be dependent on diabetes, possibly through an unidentified hormonal intermediary. Further prospective studies are necessary to elaborate the specific mechanism of this protective effect.
Methods for Assessing the Person with Alzheimer's Disease: Integrating Person-Centered and Diagnostic Approaches to Assessment

When a person is diagnosed with Alzheimer's disease or another dementia, there is a great need to understand the person both in terms of the cognitive changes and their psychological consequences. This article describes several methods by which researchers and clinicians can better understand and engage the person who is undergoing diagnostic assessment. Specific methods include (1) a modified clinical interview that targets both the person's current symptoms as well as a broader sense of their life story, and (2) standardized instruments designed to measure noncognitive aspects of living with dementia such as quality of life, activity levels, understanding of Alzheimer's disease, stigma and fear associated with Alzheimer's disease, and values and preferences regarding their life and care. The empirical basis for these measures and their clinical application are described.
Modeling Corrosion Initiation of Reinforcing Steel in Concrete: Effect of Non-diffusive Coarse Aggregate

The exposure time at which a threshold Cl— concentration, Ct, is initially achieved at the reinforcement depth in concrete, Ti, is an important service life determinant for reinforced concrete structures. However, there is no consensus in the literature of a value for Ct, as reported concentrations extend over one order of magnitude; and it has become increasingly apparent that Ct is distributed even for apparently identical specimens. In this research, models of randomly arranged coarse aggregate (CA) particles in concrete cover were generated for different aggregate types (particle size and size distribution), CA volume fraction, and cover; and, by finite element analysis, the effect of these factors on the time and location along the reinforcement at which Ct is initially achieved was investigated as a function of Ct. The results are discussed within the context of factors that contribute to the reported variability in Ct.
Kinetics of azide attack on organonitriles coordinated to pentaamminecobalt(III)

Four new 5-substituted tetrazole complexes of pentaamminecobalt(III) have been synthesized. The N-1 bonded complexes of 5-(p-methylphenyl)tetrazole, 5-(p-chlorophenyl)tetrazole, 5-(p-nitrophenyl)tetrazole and the N-2 bonded complex of 5-(m-formylphenyl)tetrazole. Kinetic studies of the complex formation reaction, wherein azide ion attacks coordinated organonitrile ligands, have been shown to follow a second order rate law, first order in nitrile complex and azide. Rate constants and activation parameters have been determined for five organonitrile complexes and a Hammett type correlation has been established for the formation reaction described by the equation log k = 2.42σ – 2.44 at 25 °C and ionic strength 1.0 M. Two mechanisms are proposed for complex formation which are consistent with our observations.
RAFT: A router architecture with frequency tuning for on-chip networks

With increasing number of cores being integrated on a single die, Network-on-Chips (NoCs) have become the de-facto standard in providing scalable communication backbones for these multi-core chips. NoCs have a significant impact on the system's performance, power and reliability. However, NoCs can be plagued by higher power consumption and degraded throughput if the network and router are not designed properly. Towards this end, this paper proposes a novel router architecture, where we tune the frequency of a router in response to network load to manage both performance and power. We propose three dynamic frequency tuning techniques, FreqBoost, FreqThrtl and FreqTune, targeted at congestion and power management in NoCs. We also propose and evaluate a novel fine-grained frequency tuning scheme where we vary the number of virtual-channels in a router dynamically. As a further optimization to these schemes, we propose a frequency tuning scheme where we tune the frequency of the four ports of a mesh router separately from the local port. As enablers for these techniques, we exploit Dynamic Voltage and Frequency Scaling (DVFS) and the imbalance in a generic router pipeline through time stealing. We also evaluate and analyze the proposed schemes from the point of view of reliability against soft error vulnerability and provide guidelines in choosing the appropriate scheme when reliability is the prime design constraint. Experiments using synthetic workloads on an 8 x 8 wormhole-switched mesh interconnect show that FreqBoost is a better choice for reducing average latency (maximum 40%) while, FreqThrtl provides the maximum benefits in terms of power saving and energy delay product (EDP). The FreqTune scheme is a better candidate for optimizing both performance and power, achieving on an average 36% reduction in latency, 13% savings in power (up to 24% at high load), and 40% savings (up to 70% at high load) in EDP. With application benchmarks, we observe IPC improvement up to 23% using our design. Our analysis shows FreqBoost to be the most robust scheme amongst the three schemes when reliability is a concern.
An Analysis of Metaphors Used by Students to Describe Energy in an Interdisciplinary General Science Course

The meaning of the term energy varies widely in scientific and colloquial discourse. Teasing apart the different connotations of the term can be especially challenging for non-science majors. In this study, undergraduate students taking an interdisciplinary, general science course (n = 49) were asked to explain the role of energy in five contexts: radiation, transportation, generating electricity, earthquakes, and the big bang theory. The responses were qualitatively analyzed under the framework of conceptual metaphor theory. This study presents evidence that non-science major students spontaneously use metaphorical language that is consistent with the conceptual metaphors of energy previously identified in the discourse of students in introductory physics, biology, and chemistry courses. Furthermore, most students used multiple coherent metaphors to explain the role of energy in these complex topics. This demonstrates that these conceptual metaphors for energy have broader applicability than just traditi...
Confirmation of research publications reported by neurological surgery residency applicants.

Abstract Objective Previous studies have reported that as many as 30% of resident and fellow applicants misrepresent their publication record on their residency and fellowship applications. To determine if neurologic surgery residency applicants were guilty of similar rates of misrepresentation, we reviewed the applications submitted to our institution in the year 2001–2002. Methods There were 102 applications submitted to our neurologic surgery residency program for the 2001–2002 academic year. All publications listed by applicants on the Central Application Service for Neurologic Surgery were verified using various online bibliographic databases including MEDLINE and an interlibrary search. Manuscripts listed as being “in press” were authenticated by contacting the journals' editorial office while those listed as either “in preparation” or “submitted for publication” were excluded. Results Seventy-three (71.6%) candidates reported 212 published citations, including 129 (61%) journal articles, 13 (6%) book chapters, and 70 (33%) printed abstracts. Twelve of these applicants also listed 13 papers as being “in press.” Overall, among the entire applicant pool, there were nine examples of possible misrepresentation in six applicants (6%). One applicant provided inadequate information to verify a book chapter. Another candidate cited four journal articles with the authors' names, even though his name was not listed among them. Two applicants included one citation each without listing any of the authors’ names. Verification of these citations revealed that neither of them was a coauthor, although one was acknowledged. Among the articles listed as “in press,” one was still under consideration for publication, and one could not be verified because of the journal's discontinuation. Conclusions We confirmed that applicants who reported their names along with their published citations did so honestly and accurately. In our study, misrepresentation of published manuscripts among neurologic surgery residency applicants was rare when compared to candidates in other specialties.
Frederick Douglass’ multiracial abolitionism: “Antagonistic cooperation” and “redeemable ideals” in the July 5 speech

Frederick Douglass spoke to a multiracial public sphere by engaging in “antagonistic cooperation” with white and black abolitionists. Far from being a relic of “black history,” he served as an “integrative ancestor” for all those trying to help build a multiracial democracy. Douglass’ July 5 Speech is placed in the context of his position at “a sort of half‐way place” between racial collectives. Douglass’ interracial rhetoric was developed to engage the different constituents of his multiracial audiences. Douglass sought to “redeem” both Enlightenment and Biblical egalitarian ideals in order to construct a multiracial “imagined community.”