cssi/SciSciGPT-SciSciNet huggingface dataset:
Sedimentation velocity behavior of closed circular SV40 DNA as a function of superhelix density, ionic strength, counterion and temperature.

Abstract Ten closed SV40 DNA's with superhelix densities (superhelical turns per ten base pairs) ranging from −0.007 to −0.085 have been prepared. This family of DNA's has been used to examine the effects of superhelix density on the sedimentation velocity behavior of closed SV40 DNA at high ionic strength in cesium chloride and sodium chloride solutions. The sedimentation coefficient increases as the absolute value of the superhelix density, ¦ σ o ¦, rises from a low value to 0.019, then decreases to a local minimum at 0.035, and finally increases steadily as ¦ σ o ¦ rises to 0.085. Examination of several of these DNA's in the electron microscope has suggested a plausible explanation for the observed non-monotonic variation of S with σ o . The sedimentation velocity-ethidium bromide titrations of these DNA's (Gray, Upholt & Vinograd, 1971) have been converted from the primary S 20 0 .∗ versus c data, in which S 20 0 .∗ is the standard sedimentation coefficient still uncorrected for the buoyant effect of bound ethidium chloride and c is the free ethidium bromide concentration, to the more meaningful S 20, w 0 versus σ form, with the aid of the coefficients in the expression for the free energy of superhelix formation developed by Bauer & Vinograd (1970a). The resultant curves form a family that is approximately superimposable on the curve for S 20, w 20 versus σ 0 in the absence of ethidium bromide. Similarly transformed sedimentation velocitydye titrations for viral PM2 DNA (6 × 10 6 daltons) and a high superhelix-density λb 2 b 5 c DNA (25 × 10 6 daltons) have the same general character and contain both a local maximum and a local minimum. The results of a study of the dependence of the sedimentation coefficient of selected SV40 DNA's upon ionic strength, the nature of the cation and temperature are consistent with the previously reported effects of these variables (Wang, 1969a) on the rotation angle of the base pairs along the helix axis.
Thermoplasmonic Membrane-Based Infrared Detector

In this letter, we experimentally demonstrate, by integrating plasmonic nanoantennas, that membrane-based micromechanical resonators can become infrared (IR) active. The photo-thermomechanical effect induced by nanoantennas enables actuation of mechanical structures. Using this hybrid nanoantenna coupled mechanical device as a thermal IR detector, we achieved a current responsivity of 12 mA/W corresponding to a displacement responsivity of 98.7 μm/W and a thermal time constant of 5.7 ms at a wavelength of 6 μm. This approach can be extended to any mechanical resonator for new optomechanical sensing modalities.
Acetylation by Tip60 Is Required for Selective Histone Variant Exchange at DNA Lesions

Phosphorylation of the human histone variant H2A.X and H2Av, its homolog in Drosophila melanogaster, occurs rapidly at sites of DNA double-strand breaks. Little is known about the function of this phosphorylation or its removal during DNA repair. Here, we demonstrate that the Drosophila Tip60 (dTip60) chromatin-remodeling complex acetylates nucleosomal phospho-H2Av and exchanges it with an unmodified H2Av. Both the histone acetyltransferase dTip60 as well as the adenosine triphosphatase Domino/p400 catalyze the exchange of phospho-H2Av. Thus, these data reveal a previously unknown mechanism for selective histone exchange that uses the concerted action of two distinct chromatin-remodeling enzymes within the same multiprotein complex.
Morphology of corticotectal cells in the primary visual cortex of hooded rats

In primary visual cortex of hooded rats, pyramidal cells in layer V may be classified as long, medium, or short, on the basis of the layer in which the apical dendrite terminates. The present study determines which of these types of pyramidal cells project to the superior colliculus. Two different strategies were used to label corticotectal cells with horseradish peroxidase (HRP). In the first set of experiments, a large number of corticotectal cells were labeled by retrograde transport following injection of HRP into the superior colliculus. In the second set of experiments, single unit recording was used to identify corticotectal cells physiologically by antidromic activation from the superior colliculus. These cells were then impaled and labeled by intracellular iontophoresis of HRP. The results from both techniques suggest that only long pyramidal cells send an axon to the superior colliculus. These cells are distinguished by an apical dendrite that extends into layer I. We conclude that in hooded rats corticotectal cells in primary visual cortex are the long pyramids in layer V.
Transmission electron microscopy of solution-processed, intrinsic and Al-doped ZnO nanowires for transparent electrode fabrication.

Summary A solution-based chemistry was used to synthesize intrinsic and Al-doped (1% and 5% nominal atomic concentration of Al) ZnO nanostructures. The nanowires were grown at 300°C in trioctylamine by dissolving Zn acetate and Al acetate. Different doping conditions gave rise to different nanoscale morphologies. The effect of a surfactant (oleic acid) was also investigated. An electron microscopy study correlating morphology, aspect ratio and doping of the individual ZnO wires to the electrical properties of the spin coated films is presented. HRTEM revealed single crystalline [0001] wires.
25 years of SIG‐III and the future of international information

The 2008 ASIS&T Annual Meeting marks the 25th anniversary of the Special Interest Group for International Information Issues. During this time the global impact of information has grown exponentially, both in terms of available information sources and how people use these sources. The members of SIG-III will present a panel looking at the past 25 years of international information issues and SIG-III's role in bringing these issues to ASIS&T as a whole for consideration and debate. Toni Carbo, one of the co-founders of SIG-III, will keynote this retrospection. A look at the past 25 years of international information offers a lens with which to view potential trends and developments in the future. Toni Carbo, Bharat Mehra, Yunfei Du, and Aaron Bowen will present a “state of the union” on aspects of international information and will evaluate trends and developments which may occur during the next 25 years. Toni will examine privacy, security, and trust. Bharat will examine access and development. Yunfei will examine the digital divide and the knowledge gap. Aaron will examine censorship. All presenters will consider the costs and benefits each topic has accrued for different countries, further challenges with respect to each topic, and potential answers countries may apply to these challenges.
Intracellular inactivation of specific nucleotide sequences: a general approach to the treatment of viral diseases and virally-mediated cancers.

Abstract A general approach is proposed for development of anti-viral complexes capable of specific intracellular inactivation of viral genetic sequences. Such complexes would consist of a specially designed bifunctional crosslinking agent bound to a single-stranded segment of virus-specific nucleic acid (the carrier). Pairing this complex with its complementary target sequence would generate covalent interstrand crosslinks between carrier and target, thereby irreversibly inactivating the target sequence. Since cells have natural mechanisms for taking up nucleic acids and pairing the newly-taken-up material with complementary sequences within the cell, it is proposed such mechanisms can be exploited for delivery of nucleic acid-agent complexes to their intracellular viral targets. The feasibility of developing and delivering such antiviral complexes is discussed in light of currently available compounds and techniques.
Influence of Dietary Phytochemicals and Microbiota on Colon Cancer Risk

Colon cancer is the third most commonly diagnosed type of cancer in the United States. Lifestyle and dietary patterns influence colon cancer risk both positively and negatively. Among the dietary factors, several plant-derived compounds have been found to afford colon cancer protection. These compounds potentially influence all aspects of colonic cellular regulation and develop complex interrelationships with the colonic microbiome. Increasing understanding of the role of microorganisms in determining the colonic environment has led to awareness of this important interrelationship among dietary factors and the microbial population. Plant-derived polyphenols are active mediators of cellular events, target key carcinogenic pathways, and modulate colonic microbial populations. In turn, the colonic microorganisms metabolize dietary compounds and mediate cellular events. In addition, the role of estrogen receptors in colon cancer and the importance of dietary components that mediate estrogen receptor-β are increasingly being discovered. Hence, dietary bioactive compounds and the intestinal microbiota create a complex milieu that directly affects the carcinogenic events of the colon. These relationships must be carefully characterized in future research to provide dietary recommendations that will reduce colon cancer risk.
Gastroparesis: Symptoms, Evaluation, and Treatment

Gastroparesis presents with gastrointestinal symptoms and nongastrointestinal manifestations in association with objective delays in gastric emptying. The condition may complicate several systemic disorders or may be idiopathic in nature. The diagnosis is made by directed evaluation to exclude organic diseases, which can mimic the clinical presentation of gastroparesis coupled with quantification of gastric emptying. Current therapies rely on dietary modifications, medications to stimulate gastric evacuation, and agents to reduce vomiting. Endoscopic and surgical options are increasingly used for cases refractory to medication treatment.
The January effect and intergenerational transfers

Abstract The Intergenerational Transfer Hypothesis asserts that the January Effect is caused by the transfer of wealth from older to younger investors at the Christmas gift-giving season. Preferences of the modal investor change; safety is less substitutable for expected returns. Assets preferred by older investors are sold. Assets that younger investors prefer are purchased. Sales of safe, highly capitalized stocks does not depress their prices, because of their high liquidity. Purchases of risky low priced small growth companies increase their prices, because markets in these stocks are more likely to be thin, and because few hedging opportunities exist. This produces the January Effect.
The metaplectic representation, weyl operators and spectral theory

Abstract Let X be the Grassmannian of Lagrangian subspaces of R 2 n and π : Θ → X the bundle of negative half-forms. We construct a canonical imbedding S ( R n ) even → C ∞ ( Θ ) which intertwines the metaplectic representation of M p ( n ) on S ( R n ) with the induced representation of M p ( n ) on C ∞ ( Θ ). This imbedding converts the algebra of Weyl operators into an algebra of pseudodifferential operators and enables us to prove theorems about the spectral properties of Weyl operators by reducing them to standard facts about pseudodifferential operators. For instance we are able to prove a Weyl theorem on the asymptotic growth of eigenvalues with an “optimal” error estimate for such operators and an analogue of the Helton clustering theorem and the Chazarain-Duistermaat-Guillemin trace formula.
Transformation of 'bandpass' linear time-variant system into equivalent 'lowpass' system

It is shown that a type of ‘bandpass’ linear time-variant differential equation has an equivalent ‘lowpass’ linear time-variant differential equation. The solution of the equivalent equation by computational techniques may proceed at a much higher rate than solution of the original equation, and offers simple computation of the amplitude and phase of the system narrowband response.
Self consistent field theories of the polymer excluded volume problem. II. Reiss' variational approach

Abstract By introducing a particular limiting process, we show that the corrected variational equations of Yeh and Ishiara for the self consistent field (SCF) are equivalent to Reiss' original result if the summation indices in the latter are appropriately defined. Thus, apart from an omitted factor of one half, Reiss' SCF is correct. This result is then compared with Edwards' SCF and a recent generalization thereof.
Unraveling the mechanism of thermal and thermo-oxidative degradation of tannic acid

Abstract The thermal and thermo-oxidative degradation of hydrolysable tannin, i.e. tannic acid is reported. The study on thermal and thermo-oxidative degradation mechanism of tannic acid was carried out by using several advanced thermal characterization techniques such as Thermogravimetric analysis (TGA) coupled with Fourier-Transform Infrared (FTIR) Spectroscopy (TGA–FTIR), pyrolysis–gas chromatography–mass spectroscopy (Py–GC–MS) and Attenuated Total Reflectance (ATR)–FTIR. The condensed phase and gaseous phase degradation studies were combined to deduce a probable degradation pathway for tannic acid molecule at high temperature under nitrogen and air atmosphere.
Consistency-based compliance: When and why do children become vulnerable?

This study examines the nature and development of behavioral consistency pressures in children. Specifically, we examined the effectiveness of the foot-in-the-door procedure in producing consistent prosocial behavior and self-attributions in kindergartners and second and fifth graders. Children were either induced to comply with a request to share prize coupons or were not given this initial prosocial experience. Those who complied either were labeled as helpful by an adult or were not. Later, children were given the opportunity to help under public or private circumstances. Moreover. children's understanding of trait stability, their internal preference for consistent behavior, and their belief that adults prefer behavioral consistency were assessed. Consistent responding began to occur within the foot-in-the-door procedure in the second grade, and this developmental shift was paralleled by a shift in children's understanding of trait stability. Furthermore, once the foot-in-the-door effect appeared among the second and fifth graders, its strength was significantly affected by the children's internal preference for consistency.
533 THE EFFECT OF CHRONIC ORAL SODIUM LOADING IN BLACKS

The effect of chronic oral sodium loading on blood pressure was studied in a representative black population ranging in age 18-22 years. All subjects (N=36) took 10 Cms/day NaCl in addition to their usual diet for 14 days. Overnight urines for Na+, K+, and creatinine were obtained two days prior to salt and on days 6, 7, 13 and 14. Casual seated BP and weight were obtained on days 0, 7 and 14. Mean arterial pressure (MAP) was calculated. A MAP increase of ≥6 mmHg considered a sodium sensitive pressure response (SS); MAP changes of ≤6 was considered sodium insensitive (SI). Urine Na excretion and Na:K ratio confirmed the high Na intake (>1.5 increase). 22 subjects (10 male, 12 female) were SI (x change= 1.45mmHg + 5.6). Weight change in the SI group was -2.7 to 2.4 kg (x = 0.2 kg). Weight increased in 8, decreased in 9, with no change in 5. 14 subjects (9 M, 5 F) were SS (x change= 11.2 mmHg + 3.3). Weight change was -1.9 to 3.3 kg (x 0.62kg). Weight increased in 8 and decreased or did not change in 6. No difference was present between groups in preload pressure (SS 117/75mmHg; SI 119/75). The diastolic BP was greater postload in the SS group ( (SS) 86 vs (SI) 75mmHg, p<.01). The results indicate different response patterns under conditions of prolonged chronic sodium load. Degrees of sodium sensitivity may be identified in a young normotensive population. The significant weight reduction following chronic sodium load in some salt sensitive subjects suggests the renal response of pressure diuresis.
The Acquisition of Syntactically Encoded Evidentiality.

This article presents several empirical studies of syntactically encoded evidentiality in English. The first part of our study consists of an adult online experiment that confirms claims in Asudeh & Toivonen (2012) that raised Perception Verb Similatives (PVSs; e.g. John looks like he is sick) encode direct evidentiality. We then present the results of an acquisition study based on an exhaustive examination of the corpora of 45 American English-speaking children in the CHILDES database (McWhinney & Snow 1985). These results are consistent with the hypothesis that children as young as two behave like adults in their ability to correlate the syntax of these constructions with the type of evidence they have. This claim is supplemented by a direct comparison of children’s and adults’ PVS constructions in the corpora. Together, the studies constitute preliminary indication of children's ability to track and grammatically encode evidence source, even in “non-evidential” languages like English.
A soil chronosequence study of the Reno valley, Italy: Insights into the relative role of climate versus anthropogenic forcing on hillslope processes during the mid-Holocene

Abstract Relatively few soil chronosequences with good age control exist for Late Pleistocene and Holocene deposits in the Mediterranean region of Europe, yet surface soils and their young buried counterparts can provide meaningful information about the timing and processes of landscape response to external forcing such as climate or anthropogenic change. Here we present the results of a study that examines a well-dated chronosequence of nineteen soil exposures in surficial deposits ranging in age from hundreds of years to hundreds of thousands of years located in the Reno River Valley near Bologna, Italy. The soil-forming climate of the Reno Valley sits on a threshold between that which facilitates the accumulation of CaCO3 and that which facilitates the translocation and formation of clay minerals and iron oxides. Once formed, secondary iron oxides are relatively immobile in oxidizing conditions in the soil profile and therefore consistently record age trends, with Feo/Fed ratios decreasing predictably with soil age for all soils in the chronosequence. The morphology of secondary carbonate accumulation and its depth of leaching also vary predictably with soil age, but only for soils younger than about ~ 12,000 years. In these young soils, horizons that contain secondary carbonate progress from relatively shallow, Stage I Bk horizons in late Holocene-aged soils to deeper Stage III Bk horizons in latest-Pleistocene aged soils. In soils older than approximately 12,000 cal ybp, however, carbonate dissolution during wetter climates and the addition of colluvium and/or dust to terrace surfaces become important factors in the preservation of carbonate in the profile, and carbonate content is not predictable by age alone. Without significant depositional additions, these older soils become decalcified. Pedogenic carbonate precipitated during drier climates is susceptible to dissolution during wetter periods, as evidenced by discontinuous carbonate coatings on grains in some soils. Therefore overall measurable pedogenic carbonate content is spatially and temporally variable as a function of input of fresh carbonate and locally-controlled soil moisture conditions. Particle size does not decrease predictably with soil age for Reno Valley soils and appears to be strongly influenced by parent material variability in younger soils and by dust additions in older soils. Our detailed examination of soil stratigraphy in the Reno Valley revealed evidence of significant aggradation of colluvium and tributary fans in the middle Holocene between ~ 6000 and ~ 4000 ybp. This aggradation pre-dates Bronze Age agricultural expansion, and appears to be instead attributable to the climate conditions of the middle Holocene that have been documented elsewhere in Italy for this time period. This study demonstrates that late Pleistocene and Holocene surface soils in the Mediterranean region of Europe can effectively help elucidate rates and processes of landscape evolution.
Testing host‐associated differentiation in a quasi‐endophage and a parthenogen on native trees

Host-associated differentiation (HAD) is the formation of genetically divergent host-associated sub-populations. Evidence of HAD has been reported for multiple insect herbivores to date, but published studies testing more than one herbivore for any given host-plant species pair is limited to herbivores on goldenrods. This limits the number of pair-wise comparisons that can be made about insect life-history traits that might facilitate or inhibit host-race development in general. Two traits previously proposed to facilitate HAD include endophagy and parthenogenesis. We tested for HAD in two herbivores, a quasi-endophagous caterpillar and a parthenogenetic aphid, feeding on two closely related species of hickories. We found that the quasi-endophage is panmictic, whereas the parthenogen exhibits HAD on their sympatric host plants, pecan and water hickory, at a geographic mesoscale. This is an important first step in the characterization of HAD in multiple insect herbivores using North American hickories, a host-plant system with many shared parthenogens.
Quality deer management: Ethical and social issues

Abstract Quality Deer Management (QDM) is emerging as a paradigm for managing white‐tailed deer populations. Examining ethical and social issues is an integral part of evaluating QDM theory and practice. Hunters’ perceptions of QDM often differ from wildlife managers’, especially with respect to the role of trophy deer, yet hunters’ cooperation is essential to successful QDM. Implementing increasing antlerless harvest while restricting buck harvest requires changes in hunters’ attitudes and behaviors. We address these human dimensions by discussing ethical and social issues, including the significance of trophy deer in hunter motivation and public perceptions of hunting, concerns about increasing privatization and elitism, enforcing QDM principles through regulation, and economic consequences of QDM. Our recommendations to wildlife managers include educating hunters and the public as well as suggestions for further research.
Identification of selected antihypertensive drugs by thin-layer chromatography

Abstract A thin-layer chromatographic procedure is described for the qualitative identification of several antihypertensive drugs including certain thiazide diuretics, spironolactone, triamterene, methyldopa and their metabolites. Utilization of new solvent developing systems and spray detecting reagents provides a method useful for the identification of these compounds in biologic fluids at low therapeutic concentrations. Sensitivity limits for these antihypertensive drugs are given, and alternate techniques to provide confirmatory analyses are also presented.
AIDS: A Challenge to Anthropologists

the media coverage play in the unfolding AIDS drama? Anthropology can add a dimension of objectivity to the examination of the AIDS phenomenon, which by this time has been inundated in the public and popular press with moralistic judgments by opponents of gay lifestyles. In addition, the studies of medical anthropologists have wider theoretical ramifications outside the discipline, particularly the implications of studies of health politics for society, of popular beliefs for culture, and of medical subcultures for clinicians.
Concentration and purification of human immunodeficiency virus type 1 virions by microfluidic separation of superparamagnetic nanoparticles.

The low concentration and complex sample matrix of many clinical and environmental viral samples presents a significant challenge in the development of low cost, point-of-care viral assays. To address this problem, we investigated the use of a microfluidic passive magnetic separator combined with on-chip mixer to both purify and concentrate whole-particle human immunodeficiency virus type 1 (HIV-1) virions. Virus-containing plasma samples are first mixed to allow specific binding of the viral particles with antibody-conjugated superparamagnetic nanoparticles, and several passive mixer geometries were assessed for their mixing efficiencies. The virus−nanoparticle complexes are then separated from the plasma in a novel magnetic separation chamber, where packed micrometer-sized ferromagnetic particles serve as high magnetic gradient concentrators for an externally applied magnetic field. Thereafter, a viral lysis buffer was flowed through the chip and the released HIV proteins were assayed off-chip. Viral pr...
The influence of equilibrium chemical reactions on vapor—liquid phase diagrams

Phase diagrams for simultaneous chemical reaction and phase equilibrium are presented for ideal and non-ideal systems. It is shown that reactive-azeotropes can occur even for ideal mixtures. The conditions for formation of reactive-azeotropes in constant-volatility systems are derived. These conditions show that for such systems reactive-azeotropes can occur only when the volatilities of the reactants are either all higher or all lower than the volatilities of the products.
Mutation analysis of the transferrin receptor-2 gene in patients with iron overload.

Three mutations in the transferrin receptor-2 gene have recently been identified in four Sicilian families with iron overload who had a normal hemochromatosis gene, HFE (C. Camaschella, personal communication). To determine the extent to which mutations in the transferrin receptor-2 gene occur in other populations with iron overload, we have completely sequenced this gene in 17 whites, 10 Asians, and 8 African Americans with iron overload and a C282C/C282C HFE genotype, as well as 4 subjects without iron overload and homozygous for the mutant HFE C282Y genotype, 5 patients with iron overload and homozygous for the mutant HFE C282Y genotype, and 5 normal individuals. None of the individuals exhibited the Sicilian mutations, Y250X in exon 6, M172K in exon 4, and E60X in exon 2. One iron-overloaded individual of Asian descent exhibited a I238M mutation which was subsequently found to be a polymorphism present in the Asian population at a frequency of 0.0192. The presence of the I238M mutation was not associated with an increase in ferritin or transferrin saturation levels. Three silent polymorphisms were also identified, nt 1770 (D590D) and nt 1851 (A617A) and a polymorphism at nt 2255 in the 3' UTR. Thus, mutations in the transferrin receptor-2 gene were not responsible for the iron overload seen in our subjects.
Intracellular metal ion chelators inhibit TNFα-induced SP-1 activation and adhesion molecule expression in human aortic endothelial cells

Abstract Endothelial adhesion molecule expression and monocyte recruitment are causal events in human atherosclerosis, and are believed to be caused, in part, by oxidative stress. Because redox-active transition metal ions, such as iron and copper, play an essential role in the generation of free radicals and the initiation and propagation of lipid peroxidation, we hypothesized that transition metal ions may also be involved in endothelial activation. Therefore, we investigated the effects of the intracellular iron-chelator, desferrioxamine (DFO), and the intracellular copper-chelator, neocuproine (NC), on TNFα-induced expression of adhesion molecules in human aortic endothelial cells (HAEC). Treatment of HAEC with DFO (0.01–0.1 mM) or NC (0.1 and 0.5 mM) time- and dose-dependently inhibited TNFα-induced protein expression of E-selectin, vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1). In contrast, iron-saturated DFO and the extracellular copper chelator, bathocuproinedisulfonic acid, had no effect on adhesion molecule expression. DFO and NC also dose-dependently inhibited TNFα-induced upregulation of adhesion molecule mRNA levels. Furthermore, treatment of HAEC with 0.5 mM DFO or NC completely inhibited TNFα-induced activation of the transcription factor, specificity protein-1 (SP-1), but only partially inhibited or did not affect activation of other transcription factors known to regulate adhesion molecule expression, i.e., nuclear factor κB (NFκB), activator protein-1 (AP-1), and interferon regulatory factor-1 (IRF-1). Finally, inhibition of endothelial nitric oxide synthase with N-nitro-L-arginine methylester (0.5 mM) did not attenuate the inhibitory effects of the metal ion chelators on adhesion molecule expression. Our data suggest that intracellular, but not extracellular, transition metal ions mediate inflammatory cytokine-induced SP-1 activation and adhesion molecule expression in endothelial cells.
Order effects in Rokeach's Value Survey☆

Abstract Two-hundred-twelve sociology students completed a version of Rokeach's Value Survey in which the presentation order of the values was randomized. Each respondent received a unique randomization pattern. Spearman's ϱ correlations were computed between the presentation order and the order of ranking done by the respondent. The magnitude of the correlations obtained was such that the amount of bias created by presentation order was sufficiently small as to suggest that order effects are not a problem in the instrument.
Enhanced sensitivity by nonuniform sampling enables multidimensional MAS NMR spectroscopy of protein assemblies.

We report dramatic sensitivity enhancements in multidimensional MAS NMR spectra by the use of nonuniform sampling (NUS) and introduce maximum entropy interpolation (MINT) processing that assures the linearity between the time and frequency domains of the NUS acquired data sets. A systematic analysis of sensitivity and resolution in 2D and 3D NUS spectra reveals that with NUS, at least 1.5- to 2-fold sensitivity enhancement can be attained in each indirect dimension without compromising the spectral resolution. These enhancements are similar to or higher than those attained by the newest-generation commercial cryogenic probes. We explore the benefits of this NUS/MaxEnt approach in proteins and protein assemblies using 1–73-(U-13C,15N)/74–108-(U-15N) Escherichia coli thioredoxin reassembly. We demonstrate that in thioredoxin reassembly, NUS permits acquisition of high-quality 3D-NCACX spectra, which are inaccessible with conventional sampling due to prohibitively long experiment times. Of critical importanc...
Intracellular events in the replication of defective interfering particles of vesicular stomatitis virus.

Abstract During a synchronous infection with both wild-type vesicular stomatitis virus (VSV) and the MS-T defective interfering (DI) particle at levels of high interference, total RNA synthesis was both reduced by 75% and shut off early as compared to the VSV infection alone. In the interfered infection the production of both VSV intracellular nucleocapsids and progeny virus was suppressed by 90% while there was a dramatic increase in intracellular MS-T nucleocapsids. There was a linear accumulation of MS-T nucleocapsids for only 5 hr with the maximum rate of synthesis being observed at 3 hr postinfection. The MS-T nucleocapsids contained genome-length, single-stranded 19 S DI RNA and were 40% of the positive (+)- and 60% of the negative (−)-strand sense. Neither the (+)- nor (−)strand of MS-T nucleocapsid RNA contained poly(A) sequences since none of the RNA or its ribonuclease digestion products bound to oligo(dT)-cellulose. We can detect no methylation of the nucleocapsid RNA and the 5′-termini were not blocked since both the (+)- and (−)-strands initiated with pppA.
Restructuring American health care financing: First of all, do no harm!

Health care costs are climbing throughout the western world. Aging populations and the costs of advanced technology are the principal forces behind much of this global increase. No country has yet succeeded in containing these growing costs other than by some form of rationing. A variety of experimental strategies, including managed competition, are being considered or tested, but none is clearly effective. American health care expenditures differ, not in that they are rising, but in their enormously high starting point. Among other things, our higher costs reflect administrative costs of more than 20%, double those of Canada and nearly triple the European average; a malpractice system that, whatever its possible advantages, costs more than 10 times as much as it pays out to the injured; the enormous medical costs of poverty; maldistribution of physician specialties and incomes; and reimbursement systems that eliminate consumer input and oversight. Restructuring the system of health care financing to bring administrative costs in line with those of other nations could save at least $70 billion annually; another $25 billion or more could be saved by replacing the malpractice system with more cost-effective alternatives. These savings could defray the costs of insuring all those not now covered, without increasing either costs to the middle class, through taxation of benefits, or total health care expenditures. With all Americans covered, the necessary restructuring of the system of health care delivery could be conducted without the current pressure for immediate drastic reform, which carries with it the risk of serious error. In dealing with the sick, physicians are taught to apply two maxims: “primum non nocere” or “first of all, do no harm!”; and the rule of therapeutic restraint. The latter states that a severe chronic illness may respond better, and with fewer complications, to gradual corrective measures than to highly aggressive therapy. Both rules could well be applied to curing the American health care system.
Full-beam asynchronous GaAs laser heterodyne

A semiconductor laser optical mixer that generates intensity-modulated light at gigahertz frequencies is described. Two independent or "asynchronous" GaAs lasers serve as sources. A novel method for wavefront alignment and source optical isolation has allowed "full-beam" mixing. Heterodyne difference frequencies as large as 10.2 GHz have been generated from both a Si-APD and a GaAs-EAP. The frequency-response characterization of both photodetectors is presented.
Trace element distributions in fractionated oceanic basalts

Abstract Oceanic tholeiites show a range of chemical composition, even from within the same dredge haul. Some concentration variations result from fractional crystallization and are initially governed by precipitation of either olivine or plagioclase. In those tholeiites characterized by olivine as the first mineral to crystallize, the early stages of fractional crystallization show decreasing concentrations of Cr and Ni. Those oceanic tholeiites characterized by plagioclase as the first mineral to crystallize do not show systematic trends in trace element concentrations in the early stages of fractionation. If the ratio FeO/MgO is used as an indicator of the degree of fractionation, then those oceanic tholeiites in which plagioclase crystallized first have higher concentrations of Sr and lower concentrations of Cr, Ga, Ni, Pb and V than samples with similar FeO/MgO ratios but in which olivine was the first mineral to crystallize.
Intermediate-range order in amorphous metal alloys

Amorphous metal alloys sometimes contain order beyond that of a simple glass. The paracrystalline model for such a metallic glass is described and its predictions compared with published data. These data were obtained by the recently developed technique of fluctuation electron microscopy (FEM), which is also described. The paracrystalline model results compare well with data from a sample that, from its diffraction pattern, was clearly polycrystalline, although with very small crystallites. The model predicts only small FEM signals from samples that appear to be amorphous by their diffraction patterns.
Tracer diffusion coefficients of oxyhemoglobin a and oxyhemoglobin s in blood cells as determined by pulsed field gradient NMR

It is demonstrated that tracer diffusion coefficients can be determined for oxyhemoglobin A (HbA-O2) and oxyhemoglobin S (HbS-O2) in intact blood cells by means of pulsed field gradient NMR (PFG-NMR). This is possible because the method discriminates between both rapidly moving water molecules and molecules having small proton transverse relaxation times (T2). The results indicate that only hemoglobin molecules contribute to the echo signals when large field gradients are used. The dependence of the measured diffusion coefficients on osmolarity and pH are attributed to changes in hemoglobin concentration resulting from changes in cell volume.
Reconstruction of paleostorms and paleoenvironment using geochemical proxies archived in the sediments of two coastal lakes in northwest Florida

Abstract Late Holocene paleoclimate records from coastal regions are important for understanding long-term variability of hurricane activity. Here we present a nearly 4000-year record of severe storm landfalls and environmental changes based on organic geochemical proxies (OGPs) preserved in sediment cores from two coastal lakes in northwest Florida. Our analysis shows that there are significant variations in δ13C, δ15N, C%, N% and C/N with depth, reflecting changes in lake environment, which in turn affected the processes delivering water and sediment to the lake as well as biological productivity within the lake. Isotopic signatures of modern organic materials in the lakes and their surrounding areas show that the major sources of sedimentary organic matters in the lakes are aquatic and terrestrial C3 vegetation. C4 grasses do not contribute significantly to the sedimentary organic matters in the lake, although they can be found in the mostly forested watershed. Thus, the positive C and N isotopic shifts, concurrent with negative shifts in C/N ratios, most likely indicate shifts to a marine-like environment in coastal lakes following the influx of marine water and nutrients and marine biota associated with major storm events. Some of these isotopic shifts observed in the sediment cores correspond to visible sand layers presumably representing overwash deposits associated with severe storm events. Radiocarbon dating of bulk sediment organic matters, wood fragments and shells indicates that the sediment in these cores was deposited over the last 3000–4000 years. Based on our age model and OGP interpretation, Eastern Lake data suggest that the recurrence interval of severe storms (i.e., large enough to cause seawater flooding of the lakes) is approximately 84 years over the last 2900 years, whereas Western lake data suggest an average recurrence interval of 86 years in the past 3900 years.
Is ABO blood group truly a risk factor for thrombosis and adverse outcomes

ABO blood type is one of the most readily available laboratory tests, and serves as a vital determinant in blood transfusion and organ transplantation. The ABO antigens are expressed not only on red blood cell membranes, determining the compatibility of transfusion, but also on the surface of other human cells, including epithelium, platelet and vascular endothelium, therefore extending the research into other involvements of cardiovascular disease and postoperative outcomes. ABO blood group has been recognized as a risk factor of venous thrombosis embolism since the 1960's, effects now understood to be related to ABO dependent variations are procoagulant factor VIII (FVIII) and von Willebrand factor (vWF) levels. Levels of vWF, mostly genetically determined, are strongly associated with venous thromboembolism (VTE). It mediates platelet adhesion aggregation and stabilizes FVIII in plasma. Moreover, many studies have tried to identify the relationship between ABO blood types and ischemic heart disease. Unlike the clear and convincing associations between VTE and ABO blood type, the link between ABO blood type and ischemic heart disease is less consistent and may be confusing. Other than genetic factors, ischemic heart disease is strongly related to diet, race, lipid metabolism and economic status. In this review, we'll summarize the data relating race and genetics, including ABO blood type, to VTE, ischemic heart disease and postoperative bleeding after cardiac surgery.
Structural effect of the Asp345a insertion in penicillin-binding protein 2 from penicillin-resistant strains of Neisseria gonorrhoeae.

A hallmark of penicillin-binding protein 2 (PBP2) from penicillin-resistant strains of Neisseria gonorrhoeae is insertion of an aspartate after position 345. The insertion resides on a loop near the active site and is immediately adjacent to an existing aspartate (Asp346) that forms a functionally important hydrogen bond with Ser363 of the SxN conserved motif. Insertion of other amino acids, including Glu and Asn, can also lower the rate of acylation by penicillin, but these insertions abolish transpeptidase function. Although the kinetic consequences of the Asp insertion are well-established, how it impacts the structure of PBP2 is unknown. Here, we report the 2.2 A resolution crystal structure of a truncated construct of PBP2 containing all five mutations present in PBP2 from the penicillin-resistant strain 6140, including the Asp insertion. Commensurate with the strict specificity for the Asp insertion over similar amino acids, the insertion does not cause disordering of the structure, but rather induces localized flexibility in the β2c-β2d loop. The crystal structure resolves the ambiguity of whether the insertion is Asp345a or Asp346a (due to the adjacent Asp) because the hydrogen bond between Asp346 and Ser362 is preserved and the insertion is therefore Asp346a. The side chain of Asp346a projects directly toward the β-lactam-binding site near Asn364 of the SxN motif. The Asp insertion may lower the rate of acylation by sterically impeding binding of the antibiotic or by hindering breakage of the β-lactam ring during acylation because of the negative charge of its side chain.
Traumatic carotid cavernous fistula

A 46-year-old man presented with a closed head injury from a motor vehicle crash. Six days after the injury, he complained of pain in his right eye and swelling of the right orbit. Physical examination revealed 6-mm proptosis associated with chemosis. A bruit was audible over the right orbit. No cranial nerves or extremity neurological deficits were evident. Cerebral angiography showed a posttraumatic carotid cavernous fistula (CCF) (A, bottom arrow) with direct opacification of the cavernous sinus and early filling of the superior ophthalmic veins (A, top arrow). Subsequently, the patient underwent transarterial coil embolization (B, arrow). The orbital bruit disappeared and chemosis rapidly decreased. He made uneventful recovery and remained without focal neurologic deficit. CCF is a communication between the cavernous portion of the carotid artery and the venous plexus of the cavernous sinus. In contrast to the spontaneous variety, post-traumatic CCF is usually from direct shunting between the carotid artery and the cavernous sinus with high flow and pressure. Although CCF can be caused by penetrating cranial injuries, severe blunt trauma is the most common mechanism. Fistulas usually appear within a few weeks after the injury with symptoms and signs related to increased venous pressure transmitted through the valveless ophthalmic veins. Orbital bruit is invariably audible and pulsating exophthalmos with chemosis are often present. With post-traumatic CCF, cerebral angiography reveals direct opacification of an enlarged cavernous sinus, early filling of ophthalmic veins, and diminished opacification of the distal arterial system (A). Complications of CCF include cranial (most commonly the sixth) nerve palsy, progressive visual impairment, and subarachnoid hemorrhage. The goal of management of CCF is occlusion of the fistula while maintaining carotid artery patency. Although surgical treatment was previously advocated, several endovascular procedures have recently been used to achieve this goal. Because percutaneous embolization of CCF effects occlusion of the fistula and carries low morbidity and mortality, it is currently considered the treatment of choice.
Who uses transesophageal echocardiography in the operating room

A survey was made of 155 anesthesiology residency programs in the United States to determine the patterns of use, responsibility for interpretation, and training of those responsible for intraoperative transesophageal echocardiography (TEE).Survey questions included numbers and types of cases for wh
Theoretical foundation of a textured decomposition algorithm

A textured decomposition method (TDM) is proposed for large-scale convex optimization problems, in which a problem is reduced to a set of more tractable subproblems by rotatingly fixing some complicating (interaction or coupling) variables. The approach is appealing since mutually independent subproblems can be solved in parallel. Accordingly, the TDM selves a large-scale convex optimization problem by iteratively solving a sequence of concurrent subproblems. Necessary and sufficient conditions to guarantee that the converged solution of the TDM be the optimal solution of the original problem are addressed.
Targets and delivery methods for therapeutic angiogenesis in peripheral artery disease

Therapeutic angiogenesis utilizing genetic and cellular modalities in the treatment of arterial obstructive diseases continues to evolve. This is, in part, because the mechanism of vasculogenesis, angiogenesis, and arteriogenesis (the three processes by which the body responds to obstruction of large conduit arteries) is a complex process that is still under investigation. To date, the majority of human trials utilizing molecular, genetic, and cellular modalities for therapeutic angiogenesis in the treatment of peripheral artery disease (PAD) have not shown efficacy. Consequently, the current available knowledge is yet to be translated into novel therapeutic approaches for the treatment of PAD. The aim of this review is to discuss relevant scientific and clinical advances in therapeutic angiogenesis and their potential application in the treatment of ischemic diseases of the peripheral arteries. Additionally, this review article discusses past and recent developments, such as some unconventional approaches that have the potential to be applied as therapeutic targets. The article also includes advances in the delivery of genetic, cellular, and bioactive endothelial growth factors.
Thiol methylation potential in anoxic, low-pH wetland sediments and its relationship with dimethylsulfide production and organic carbon cycling.

Dimethylsulfide (CH3SCH3) is formed in anoxic freshwater sediments by biological methylation of methanethiol (CH3SH). We measured thiol methylation potential in low-pH, Sphagnum peat sediments from Alaska and Alabama by adding ethanethiol (CH3CH2SH) to peat slurries and quantifying the rate of ethylmethylsulfide (CH3CH2SCH3) formation. Thiol methylation potential ranged from 12 to 154 nM h−1 and was significantly related to dimethylsulfide accumulation rates (P=0.0007; r2=0.48). Addition of methanol or syringic acid stimulated thiol methylation potential and dimethylsulfide accumulation rate, suggesting that these compounds could be methyl donors. Addition of acetate or its metabolic precursors (glucose or Sphagnum plant material) inhibited thiol methylation potential, but not carbon dioxide or methane production. Inhibition of methanogenesis with either 2-bromoethanesulfonic acid or KNO3 consistently inhibited thiol methylation potential and dimethylsulfide accumulation. These results suggest that methanogens play a role in thiol methylation and therefore dimethylsulfide formation.