cssi/SciSciGPT-SciSciNet huggingface dataset:
Probing the surface of Neisseria gonorrhoeae: immunoelectron microscopic studies to localize cyanogen bromide fragment 2 in gonococcal pili

Summary Common epitopes accessible to antibody on purified macromolecules or structurally altered gonococci may not be accessible to antibody when those macro-molecules are in their native state on the surface of intact organisms. To determine the immunologic accessibility of cyanogen bromide fragment 2 (CNBr2), a portion of the gonococcal pilin molecule that is common to all gonococcal strains on the surface of viable gonococci, probes composed of specific CNBr2 antibodies linked to gold spheres were manufactured. When whole piliated gonococci were exposed to these anti-CNBr2 immunological probes and examined using transmission electron microscopy, no significant marking of native pili was evident. These probes, however, detected CNBr2 in purified form. The epitopes encompassed within the CNBr2 portion of pili appear to be inaccessible to anti-CNBr2 probes within native gonococcal pili.
Locally implicit solution of a reaction-diffusion system with stiff kinetics

The Tyson-Fife reaction-diffusion equations are solved numerically using a locally implicit approach. Since the variables evolve at very different time scales, the resulting system of equations is stiff. The reaction term is responsible for the stiffness and the time step is increased by using an implicit method. The diffusion operator is evaluated explicitly and the system of implicit nonlinear equations is decoupled. The method is particularly useful for parameter values in which the equations are very stiff, such as the values obtained directly from the experimental reaction rate constants. Previous efforts modified the parameters on the equations to avoid stiffness. The equations then become a simplified model of excitable media and, for those cases, the locally implicit method gives a faster although less accurate solution. Nevertheless, since the modified equations no longer represent a particular chemical system an accurate solution is not as important. The algorithm is applied to observe the transition from simple motion to compound motion of a spiral tip.
Interfacing silicon nanowires with mammalian cells

We present the first demonstration of a direct interface of silicon nanowires with mammalian cells such as mouse embryonic stem (mES) cells and human embryonic kidney (HEK 293T) cells without any e...
Statistics of the fractionally charged excitations in the quantum Hall effect

The statistical angle of charged excitations in the quantum Hall effect are determined from the adiabatic theorem for all allowed rational filling factors. The relevance of this to the odd-denominator rule as well as the extension to the case of interacting bosons is discussed.
Spatially Prioritizing Seafloor Mapping for Coastal and Marine Planning

Coastal and marine areas provide vital services to support the economic, cultural, recreational, and ecological needs of human communities, but sustaining these benefits necessitates a balance between growing and often competing uses and activities. Minimizing coastal zone conflict and reducing human-induced impacts to ecological resources requires access to consistent spatial information on the distribution and condition of marine resources. Seafloor mapping provides a detailed and reliable spatial template on the structure of the seafloor that has become a core data need for many resource management strategies. The absence of detailed maps of the seafloor hinders the effectiveness of priority setting in marine policy, regulatory processes, and marine stewardship. For large management areas, the relatively high cost of seafloor mapping and limited management budgets requires careful spatial prioritization. In order to address this problem, a consensus based approach, aided by decision-support tools, and ...
The effect of viscosity on the accessibility of the single tryptophan in human serum albumin

When reactions take place with one of the reactants tied to protein matrix, movements along the reaction coordinate towards the transition state can become coupled to structural fluctuations of the protein matrix. This investigation aims to test the assumptions underlying the arguments supporting such a coupling. A coupling is allowed only if the activation barrier is high and broad enough as shown to be the case for the proton catalyzed isotope exchange at Trp-63 of lysozyme. In the present investigation the activation barrier for the same reaction has been lowered radically in an effort to show that the coupling, as measured by the dependence of rate on solution viscosity, will diminish and ideally vanish, despite the unchanged effects of cosolvents on the chemical activities of all the reactants. The isotope exchange rate at the indole nitrogen of the single tryptophan residue of human serum albumin was measured with UV. This residue is rigidly held to the protein surface and the solvent access, although restricted, corresponds to a partially exposed residue. As a consequence, the isotope exchange rates and the bimolecular quenching rate of fluorescence by acrylamide, also measured, are high. The experiments were carried out at pH 5.2 where the molecule is in the N-form and the exchange is catalyzed by OH- ions. The activation energy of the hydroxyl catalyzed reaction is 22 kJ lower than for the proton catalyzed process. Under these conditions the exchange rate is viscosity independent both in the case of glycerol and in ethylene glycol.(ABSTRACT TRUNCATED AT 250 WORDS)
Hoarding in the Community: A Code Enforcement and Social Service Perspective

ABSTRACT Hoarding behaviors endanger individuals and their communities. Although there is a growing literature on clinically referred and elderly hoarders, there is limited information about hoarding behaviors beyond these contexts. This study examines the frequency, characteristics, and outcomes of cases involving hoarding encountered by code enforcement officials and social service staff. Prior to an in-service training, 236 social service staff members completed a 43-item survey about their experiences with cases involving hoarding. Respondents reported encountering between two and three cases per year. Although these hoarding cases were estimated to cost more than $3,700 in cleaning fees, 83% of respondents reported having received no prior training on dealing with hoarding. Survey responses suggested that hoarding situations were difficult to resolve and involved multiple community agencies. Collectively, hoarding behaviors appear to be a problem regularly encountered by social service members, who o...
Chromatin-nuclear membrane attachment in relation to DNA replication and chromosome aberrations: a new hypothesis.

A hypothesis is presented which explains chromosome breakage by considering possible relationship between chromatin material and nuclear membrane. It also explains the changes in sites of breaks in chromosomes by the same radiomimetic agent when applied during different phases of the cell cycle. It is discussed how some of the agents incapable of causing chromosome aberrations can (1) enhance the potential of radiomimetic agents in causing chromosome breakage and/or (2) reduce the possibility of somatic crossing over both at the genetic as well as the cytological level.
Educational Aspects of the Solar Splash Regatta

The rationale behind and the educational goals of the Solar Splash intercollegiate solar/ electric boat competition are examined. An assessment is made as to how well these educational goals are being met, including a brief discussion of competition participant problems. An apparent 'mismatch is identified between the Solar Splash rules and resultant boat designs and the goals for most collegiate engineering design courses, and possible methods of correction are discussed.
DRUG USE AND DESISTANCE PROCESSES

Sampson and Laub's age-graded theory of informal social control emphasizes the importance of adult social bonds such as marriage and stable employment in redirecting behavior in a more prosocial direction. Heavy alcohol use has also been shown to influence persistent patterns of offending as well as more episodic offending across the life course. Sampson and Laub's life-course theory emphasizes the negative impact of alcohol use on marital and employment bonds. Although alcohol has indeed been shown to have significant effects on criminal offending, we argue that drug use and the drug culture in which many contemporary offenders are enmeshed have consequences that often complicate desistance processes in ways that alcohol does not. Drug use and its lifestyle concomitants bring together a host of distinctive social dynamics that compromise multiple life domains. The current project investigates the role of drug use on desistance processes relying on a contemporary sample of previously institutionalized youth. We draw on three waves of data from the Ohio life-course study, a project that spans some 21 years. The results support the assertion that drug use exerts unique effects on desistance processes, once levels of alcohol use are taken into account. We investigate possible mechanisms that help to explain the differential impact of drug use on offending and find that social network effects, particularly partner criminality, explain some but not all of the negative impact of drug use on life-course patterns of criminal offending.
Presidentialism, Elections and Representation

How does presidentialism affect various forms of representation? All else being equal, presidentialism is likely to impede the prospects for ‘mandate’ representation but enhance the prospects for ‘accountability’ representation. The degree of mandate or accountability representation is a function of the balance of powers and the degree of separation of purpose between the branches. Strong presidentialism works against mandate representation by freeing the president from his/her legislative copartisans and promoting ‘policy switching’. In contrast, a high ‘separation of purpose’, defined primarily by a country’s electoral institutions, clarifies for voters the responsibility of each branch for policy. Thus presidentialism - under certain common institutional configurations - provides accountability representation to a degree overlooked by existing research.
The electricity impacts of Earth Hour: An international comparative analysis of energy-saving behavior

Abstract The annual Earth Hour event is a coordinated, mass effort to reduce electricity consumption for 1 h. Earth Hour's objective is to call attention to environmentally sustainable action through the collective impact made when individuals, businesses, governments and communities voluntarily combine electricity conservation efforts. Earth Hour events have taken place worldwide since 2007. We compiled 274 measurements of observed changes in electricity demand caused by Earth Hour events in 10 countries, spanning six years. These events reduced electricity consumption an average of 4%, with a range of +2% (New Zealand) to −28% (Canada). While the goal of Earth Hour is not to achieve measurable electricity savings, the collective events illustrate how purposeful behavior can quantitatively affect regional electricity demand. Similar actions may be a useful demand-control strategy during temporary electricity shortfalls or other crises. The policy challenge is to convert these short-term events into longer-term actions, including sustained changes in behavior and investment. Other events cause coordinated change in electrical demand, such as television programs and sporting events. These sharp drops and peaks lead to inefficient generation requirements and, potentially, grid failure. These events demonstrate the importance of short-term behavior on energy demand and possible applications to energy policies.
Nicotinic acid and alcohol-induced lipemia.

Abstract Nicotinic acid, administered orally in six 100 mg doses spaced one hour apart, markedly reduced the usual alcohol-induced enhancement of alimentary lipemia in man. In rats, 200 mg of nicotinic acid/kg body weight inhibited the increase in post-prandial plasma and liver triglycerides associated with ingestion of a corn oil-alcohol mixture, and reduced incorporation of the 14 C-labeled dietarv fat into plasma triglycerides.
The overlapping coefficient as a measure of agreement between probability distributions and point estimation of the overlap of two normal densities

The overlapping coefficient is defined as a measure of the agreement between two probability distributions. Its relationship to the dissimilarity index and its propertie are described. An extensive treatment of maximum-likelihood estimation of the overlap between two normal distributions is presented as an example of estimating the overlapping coefficient from sample data.
Immunosensing of Staphylococcus enterotoxin B (SEB) in milk with PDMS microfluidic systems using reinforced supported bilayer membranes (r-SBMs)

A versatile and novel method has been developed for microfluidic immunosensing of the food-borne pathogen Staphylococcus enterotoxin B (SEB) in poly(dimethylsiloxane) (PDMS) chips. Supported bilayer membranes (SBMs) were generated by vesicle fusion in oxidized PDMS microchannels for minimizing non-specific adsorption of biomolecules. The stability of SBMs was strengthened with a streptavidin layer to make them air-stable and allow for subsequent display of the biotin-functionalized antibodies. The reinforced supported bilayer membranes (r-SBMs) are fluid, exhibiting a lateral diffusion coefficient of ∼1.9 µm2 s−1, and no detectable change of mobility was found after dehydration/rehydration. This is a substantial improvement over phosphatidylcholine (PC) membranes on PDMS, which suffered a roughly 10% reduction in the mobile fraction and 30% decrease in mobility after dehydration. Non-specific protein adsorption in the membrane-treated channels was reduced 100–1000 fold as compared to PDMS surfaces without a membrane coating. A flow-based microfluidic immunosensor for SEB was developed using antibodies linked to the r-SBMs in PDMS channels, and a detection limit of 0.5 ng mL−1 was obtained from the linear portion of the calibration curve. The microchip was applied to detection of SEB in milk, and similar response and sensitivity were obtained, demonstrating the sensor's remarkable performance for real world samples. The r-SBMs overcome the stability hurdle in SBM-modified surfaces, opening up possibilities for transport and storage of membrane-functionalized microchips in the dehydrated form without compromising the performance, and facilitating the commercialization of disposable SBM-based microdevices.
DeMOR: decentralized model order reduction of linear networks with massive ports

Model order reduction is an efficient technique to reduce the system complexity while producing a good approximation of the input-output behavior. However, the efficiency of reduction degrades as the number of ports increases, which remains a long-standing problem. The reason for the degradation is that existing approaches are based on a centralized framework, where each input-output pair is implicitly assumed to be equally interacted and the matrix-valued transfer function has to be assumed to be fully populated. In this paper, a decentralized model order reduction scheme is proposed, where a multi-input multi-output (MIMO) system is decoupled into a number of subsystems and each subsystem corresponds to one output and several dominant inputs. The decoupling process is based on the relative gain array (RGA), which measures the degree of interaction of each input-output pair. Our experimental results on a number of interconnect circuits show that most of the input- output interactions are usually insignificant, which can lead to extremely compact models even for systems with massive ports. The reduction scheme is very amenable for parallel computing as each decoupled subsystem can be reduced independently.
Radiotracer experiments on carbon formation in zeolites. II

Abstract Carbon deposition in a 10-ring zeolite was traced with radioactively labeled mixtures of hexane and aromatics and was compared with earlier results on 12-ring structures. Although coke yields differed by 1 to 2 orders of magnitude between the two structural classes, it was shown that the origin of the carbon deposits in both was strikingly similar, involving nearly equal participation of both paraffin and aromatic. The data supported the assertion that coke results from the transformation and reaction of alkylaromatics, those transformations being sterically inhibited within the restrictive dimensions of a 10-ring pore.
SCH 79797, a selective PAR1 antagonist, limits myocardial ischemia/reperfusion injury in rat hearts

Myocardial ischemia/reperfusion (I/R) injury is partly mediated by thrombin. In support, the functional inhibition of thrombin has been shown to decrease infarct size after I/R. Several cellular responses to thrombin are mediated by a G-protein coupled protease-activated receptor 1 (PAR1).However, the role of PAR1 in myocardial I/R injury has not been well characterized. Therefore, we hypothesized that PAR1 inhibition will reduce the amount of myocardial I/R injury. After we detected the presence of PAR1 mRNA and protein in the rat heart by RT-PCR and immunoblot analysis,we assessed the potential protective role of SCH 79797, a selective PAR1 antagonist, in two rat models of myocardial I/R injury. SCH 79797 treatment immediately before or during ischemia reduced myocardial necrosis following I/R in the intact rat heart. This response was dose-dependent with the optimal dose being 25 microg/kg IV. Likewise, SCH 79797 treatment before ischemia in the isolated heart model reduced infarct size and increased ventricular recovery following I/R in the isolated heart model with an optimal concentration of 1 microM. This reduction was abolished by a PAR1 selective agonist. SCH 79797-induced resistance to myocardial ischemia was abolished by wortmannin, an inhibitor of PI3 kinase; L-NMA, a NOS inhibitor; and glibenclamide, a nonselective K(ATP) channel blocker. PAR1 activating peptide,wortmannin, L-NMA and glibenclamide alone had no effect on functional recovery or infarct size. A single treatment of SCH 79797 administered prior to or during ischemia confers immediate cardioprotection suggesting a potential therapeutic role of PAR1 antagonist in the treatment of injury resulting from myocardial ischemia and reperfusion.
Endocytic Traffic: Vesicle Fusion Cascade in the Early Endosomes

Summary New research shows that vesicles in the early endosomal network coalesce according to a classical theoretical description of aggregation put forward by Smoluchowski more than 100 years ago. This gives a new tool for unraveling complexities of the endocytic pathways.
Sex Differences in the Relationship of Self Concept to Locus of Control in Children

The Coopersmith (1967) Self Esteem Inventory was given to 480 third and fourth grade children. From the distribution- of inventory scores, 28 boys and 28 girls were selected to form a 2x2 classification of low and high self-concept males and females. The Intellectual Achievement Questionnaire (Crandall, Katkovsky, and Crandall, 1965) was administered to determine if the four groups differed in accepting personal responsibility for success and/or failure. High self-concept boys were found to demonstrate a higher total index of internal locus of control than low self-concept boys while the converse was true of high and low self-concept girls (p <.025). Although high self-con cept boys were generally more internal than high self-concept girls (p <.05), high self-concept children, regardless of sex, assumed more personal responsibility for successful outcomes than failures (p <.01).
The net flux of inorganic matter by an intertidal oyster reef

Inorganic particulate material uptake and release over an oyster reef during a tidal cycle was measured every 11.8 days for one year. There was a net uptake on the flooding tides and a net release on ebbing tides. Particulate uptake was highest in late summer reaching a maximum of 230 g m−2 h−1. Particulate release was also highest in late summer reaching a maximum of 94 g m−2 h−1. On an annual basis, 86.7 kg m−2 y−1 of inorganic particulate material was taken up on flooding tides and 56.5 kg m−2 y−1 was released on ebbing tides. The pattern of uptake on flooding tides and release on ebbing tides was hypothesized to be the result of higher water velocities on ebbing tides.
Temporal shape analysis of Nd: YLiF active modelocked/Q-switched oscillator

Abstract Using a third harmonic correlation technique, the pulse shape of an active modelocked/Q-switched Nd 3+ :YLiF oscillator was investigated as a function of various laser parameters. Particular emphasis was put on the source and the magnitude of prepulses for various oscillator conditions so that appropriate methods for their removal can be chosen.
THREE-DIMENSIONAL MODEL FOR INTERDIFFUSED QUANTUM DOTS

We report the study of the interdiffusion effect of quantum-dot (QD) heterostructures, focusing on the theoretical calculation of the electronic structure of interdiffused QDs. A computational model has been developed for QD superlattice system using Hamiltonian in reciprocal space domain to analyze the interdiffusion effect on electronic structure. The interdiffusion effects of QDs with various geometries having the same volume and the same lattice constant have been studied. In general, the interdiffusion effect in QDs is significantly pronounced since it occurs in three dimensions. Comparing the interdiffusion effect for the various shapes of QDs, it was found that the spherical QD has the lowest ground state and produces the largest blue-shift during the interdiffusion or intermixing process.
Disaster and Security: Colorado State Style

On July 28, 1997, Colorado State University suffered a devastating water disaster that seriously damaged more than thirty campus buildings, including Morgan Library and more than 500,000 volumes in its basement. The resulting response and recovery efforts took seven years, multimillion dollars, and thousands of staff hours. From the first night, safety and security issues were integral to the disaster response and recovery efforts. This article focuses on security during and immediately after the disaster, our effort to assess the extent of damage to the collection, representing our interests to the insurance company, and our risk-management efforts after the disaster and how they have changed our security policies and procedures.
Hybrid orbitals and the runge–lenz vector

Matrix elements of the Runge-Lenz vector A are presented for those linear combinations of degenerate hydrogenic functions often referred to as hybrid orbitals. The uncertainties in the components of A for each type of wave-function are related to the distribution of classical Kepler orbits corresponding to each function. Matrix elements of A with respect to radially nodeless Slater functions are presented, as these functions are often used as a basis set in atomic and molecular calculations. The properties of A for a piecewise Coulombic central field are discussed in relation to the description of penetrating orbits in the old quantum theory. Simultaneous eigenfunctions of A and the Hamiltonian cannot be chosen for the piecewise Coulombic field because of a discontinuity in the radial derivative of the potential energy.
VLSI Process modeling&#8212;SUPREM III

Over the past several years, the process-simulation tool SUPREM II has proven useful in the design and optimization of both bipolar and MOS technologies. This paper describes a new and significantly more capable version of the program--SUPREM III--which incorporates process models suitable for VLSI device design. This new version of the program is now generally available and should provide a powerful new tool in VLSI design. For the first time, the program models multilayer structures (up to five material layers). It also incorporates substantially upgraded diffusion, oxidation, ion implantation, and other process models. These models incorporate, where possible, recent thinking about underlying physical mechanisms. The program remains a one-dimensional simulator; extensions to two dimensions are discussed. This paper concentrates on the process models and their underlying physics; implementation issues are addressed elsewhere.
Genome editing: a tool for research and therapy: towards a functional understanding of variants for molecular diagnostics using genome editing.

Genome Editing: A Tool For Research and Therapy: Towards a functional understanding of variants for molecular diagnostics using genome editing
Factors that influence intraocular pressure changes after myopic and hyperopic LASIK and photorefractive keratectomy: a large population study.

Purpose To describe the factors that influence the measured intraocular pressure (IOP) change and to develop a predictive model after myopic and hyperopic LASIK and photorefractive keratectomy (PRK) in a large population. Design Retrospective, observational case series. Participants Patients undergoing primary PRK or LASIK with a refractive target of emmetropia between January 1, 2008, and October 5, 2011. Methods The Optical Express database was queried for all subjects. Data were extracted on procedure specifics, preoperative central corneal thickness (CCT), IOP (using noncontact tonometry), manifest refraction, average keratometry, age, gender, and postoperative IOP at 1 week, 1 month, and 3 months. A linear mixed methods model was used for data analysis. Main Outcome Measures Change in IOP from preoperatively to 1 month postoperatively. Results A total of 174 666 eyes of 91 204 patients were analyzed. Hyperopic corrections experienced a smaller IOP decrease than myopic corrections for both PRK and LASIK ( P 0.0001). Patients who underwent LASIK had a 0.94 mmHg (95% confidence interval [CI], 0.89–0.98) greater IOP decrease than patients who underwent PRK ( P 0.0001), reflecting the effect of the lamellar flap. The decrease in IOP was linearly related to preoperative manifest spherical equivalent (MSE) for myopic PRK and LASIK ( P 0.0001), weakly correlated with preoperative MSE after hyperopic LASIK, and not related to preoperative MSE after hyperopic PRK. The single greatest predictor of IOP change was preoperative IOP across all corrections. By using the available data, a model was constructed to predict postoperative IOP change at 1 month; this was able to explain 42% of the IOP change after myopic LASIK, 34% of the change after myopic PRK, 25% of the change after hyperopic LASIK, and 16% of the change after hyperopic PRK. Conclusions Myopic procedures lower measured IOP more than hyperopic procedures; this decrease was proportional to the amount of refractive error corrected. Independent of the refractive correction, the creation of the lamellar LASIK flap decreased measured IOP by 0.94 mmHg. A best-fit model for IOP change was developed that may allow better interpretation of post-laser vision correction IOP values.
On damping mechanisms in beams

A partial differential equation model of a cantilevered beam with a tip mass at its free end is used to study damping in a composite. Four separate damping mechanisms consisting of air damping, strain rate damping, spatial hysteresis and time hysteresis are considered experimentally. Dynamic tests were performed to produce time histories. The time history data is then used along with an approximate model to form a sequence of least squares problems. The solution of the least squares problem yields the estimated damping coefficients. The resulting experimentally determined analytical model is compared with the time histories via numerical simulation of the dynamic response. The procedure suggested here is compared with a standard modal damping ratio model commonly used in experimental modal analysis.
Early alterations in amino acid pools and protein synthesis of diploid fibroblasts stimulated to synthesize DNA by addition of serum.

Diploid human fibroblasts in culture (WI 38) were allowed to reach a stationary phase and were then stimulated to reenter DNA synthesis and cell division by addition of serum to the culture medium. The rate of protein synthesis increased during the first hours after addition of serum reaching at three hours a plateau value that continued for at least 24 hours after serum addition. Inhibition of protein synthesis during the early hours after serum addition abolished the stimulation of DNA synthesis occurring 20 to 28 hours later. Increased protein synthesis was preceded by a rapid decrease in the intracellular pool size of most amino acids. These changes were independent of concomitant protein synthesis. They suggest that serum exerts an immediate effect on the function of the cell membrane.
Environmental Sustainability: A Definition for Environmental Professionals

While acknowledging the need for “sustainability,” this paper summarizes the problems that have been encountered in our understanding and use of this concept. It explores the efforts of others to define the concept within the context of specific disciplinary areas and sets forth a proposal for a basic understanding of the term “environmental sustainability” as an expansion of our common perception of the nature of human activity so as to more clearly connect it with the ecological concept of interdependence and to serve as a goal for environmental managers. John Morelli Rochester Institute of Technology john.morelli@rit.edu
One-pot diastereoselective assembly of helicates based on a chiral salen scaffold

Abstract The one-pot reaction of (1S,2S)-(+)-1,2-diaminocyclohexane, 3-tert-butyl-2-hydroxybenzaldehyde and Zn(OAc)2·1.5H2O in methanol under reflux gives the diastereoselective formation of the first zinc(II)-salen double helicate, P-(S, S)-1, which adopts a right-handed helicity. The stereochemistry of the helicates can be readily tuned through varying the chiral diamine backbone.
A comparison of front-of-pack nutrition claims between the US and EU

Purpose – This paper aims to compare the use of front-of-pack nutrition claims made on 32,257 food labels launched in 2009 in the US and the EU. Design/methodology/approach – Information from Mintel's Global New Product Database was analyzed, for 25,417 products launched in the EU and 6,840 in the US. The hypothesis was that “products launched in the US and EU have a different frequency of front-of-pack nutrition claims”. Using inferential statistics, significant differences (two-tailed Z-tests) in the number of claims are explored and compared to differences in legislation standards and consumer preferences. Findings – The initial analysis revealed that there were six significant differences between the presence of the seven health and nutrition claims across 16 product categories in the US and the EU. Further analysis of the 16 product categories revealed a range of significant differences between the frequency of US and EU claims. Originality/value – The emerging relevance of front-of-pack nutrition la...
The consequences of hydroxyl radical formation on the stoichiometry and kinetics of ferrous iron oxidation by human apoferritin.

Despite previous detection of hydroxyl radical formation during iron deposition into ferritin, no reports exist in the literature concerning how it might affect ferritin function. In the present study, hydroxyl radical formation during Fe(II) oxidation by apoferritin was found to be contingent on the "ferroxidase" activity (i.e., H subunit composition) exhibited by apoferritin. Hydroxyl radical formation was found to affect both the stoichiometry and kinetics of Fe(II) oxidation by apoferritin. The stoichiometry of Fe(II) oxidation by apoferritin in an unbuffered solution of 50 mM NaCl, pH 7.0, was approximately 3.1 Fe(II)/O(2) at all iron-to-protein ratios tested. The addition of HEPES as an alternate reactant for the hydroxyl radical resulted in a stoichiometry of about 2 Fe(II)/O(2) at all iron-to-protein ratios. HEPES functioned to protect apoferritin from oxidative modification, for its omission from reaction mixtures containing Fe(II) and apoferritin resulted in alterations to the ferritin consistent with oxidative damage. The kinetic parameters for the reaction of recombinant human H apoferritin with Fe(II) in HEPES buffer (100 mM) were: K(m) = 60 microM, k(cat) = 10 s(-1), and k(cat)/K(m) = 1.7 x 10(5) M(-1) x (-1). Collectively, these results contradict the "crystal growth model" for iron deposition into ferritin and, while our data would seem to imply that the ferroxidase activity of ferritin is adequate in facilitating Fe(II) oxidation at all stages of iron deposition into ferritin, it is important to note that these data were obtained in vitro using nonphysiologic conditions. The possibility that these findings may have physiological significance is discussed.
TRIF Is Required for TLR4 Mediated Adjuvant Effects on T Cell Clonal Expansion

Toll like receptor 4 (TLR4) is an important pattern recognition receptor with the ability to drive potent innate immune responses and also to modulate adaptive immune responses needed for long term protection. Activation of TLR4 by its ligands is mediated by engagement of the adapter proteins MyD88 (myeloid differentiation factor 88) and TRIF (Toll-interleukin 1 receptor domain-containing adapter inducing interferon-beta). Previously, we showed that TRIF, but not MyD88, plays an important role in allowing TLR4 agonists to adjuvant early T cell responses. In this study, we investigated the T cell priming events that are regulated specifically by the TRIF signaling branch of TLR4. We found that TRIF deficiency prevented the TLR4 agonist lipid A from enhancing T cell proliferation and survival in an adoptive transfer model of T cell priming. TRIF deficient DC showed defective maturation as evidenced by their failure to upregulate co-stimulatory molecules in response to lipid A stimulation. Importantly, TRIF alone caused CD86 and CD40 upregulation on splenic DC, but both TRIF and MyD88 were required for CD80 upregulation. The impairment of T cell adjuvant effects and defective DC maturation in TRIF lps/lps mice after TLR4 stimulation was mainly due to loss of type I IFN production, indicating that type I interferons are central to TLR4's adjuvant effects. These results are useful for the continued development of TLR4 based vaccine adjuvants that avoid inflammatory risks while retaining beneficial immune response.
Restructuring of Hog Farming in North Carolina: Explosion and Implosion

Over the past six years hog farming in North Carolina has undergone a significant restructuring. For most of this century raising hogs was a casual farm activity found throughout the state. During the past decade hog farming has been transformed along industrial-corporate lines. In the process, the swine population has expanded rapidly (exploded) and simultaneously collapsed in geographical bounds (imploded). This paper examines the linkage between the development of the industrial-corporate hog farming regime, the rapid growth in hog populations, and the geographical concentration of hog production in a newly emerging high-density hog production district in the south central area of the Coastal Plain region.
Fat Distribution in Relation to Drug Use, Human Immunodeficiency Virus (HIV) Status, and the Use of Antiretroviral Therapies in Hispanic Patients with HIV Infection

Human immunodeficiency virus (HIV)-associated fat-redistribution syndrome is still a subject of controversy. There is, as yet, little agreement on the definition, etiology, and prevalence of the syndrome. Many studies have examined medication or disease-related factors. Fewer studies have examined patient-related factors. Illicit drug use is an important risk factor for HIV infection, yet the role of drug use in fat distribution has not been well described. We examined fat distribution, measured by dual energy x-ray absorptiometry, in relation to drug use, smoking, and alcohol use in Hispanic patients with HIV infection and control group of HIV-negative drug users. Our results suggest that neither drug use nor alcohol consumption are predictors of fat distribution. However, among men, smoking was independently associated with less total fat, less trunk fat, and more appendicular fat. The role of patient-specific factors in the etiology of HIV-associated fat-redistribution syndrome warrants further investigation.
Cerebral blood flow and metabolism following pancuronium bromide in newborn lambs.

ABSTRACT: The purpose of this study was to evaluate cerebral blood flow and metabolism following pancuronium bromide paralysis in healthy newborn lambs. Cerebral blood flow and cerebral metabolic rate for O2 and glucose were measured along with blood pressure and blood gases before and again at 15 and 60 min following pancuronium paralysis in seven newborn lambs. Pancuronium bromide paralysis had no effect on any of these parameters either at 15 or 60 min of paralysis. Total cerebral blood flow, cerebral metabolic rate for O2, and cerebral metabolic rate for glucose were 87 + 6 ml/min/100 g, 258 ± 10 μmol O2/min/100 g, and 53 ± 10 mmol glucose/min/100 g, respectively. Neither was any change in regional cerebral blood flow noted. In spite of being connected immediately to the ventilator, however, some animals experienced a transient increase (average = 32%) in blood pressure, that was not associated with an increase in end tidal CO2. The data suggest that pancuronium paralysis in healthy awake newborn lambs does not lead to any alteration in cerebral blood flow or metabolism.
A Critical Appraisal of the Role of Insulin Analogues in the Management of Diabetes Mellitus

Insulin is one of the oldest and best studied treatments for diabetes mellitus. Despite many improvements in the management of diabetes, the nonphysiological time-action profiles of conventional insulins remain a significant obstacle. However, the advent of recombinant DNA technology made it possible to overcome these limitations in the time-action profiles of conventional insulins. Used as prandial (e.g. insulin lispro or insulin aspart) and basal (e.g. insulin glargine) insulin, the analogues simulate physiological insulin profiles more closely than the older conventional insulins. If rapid-acting insulin analogues are used in the hospital, healthcare providers will need a new mind-set. Any error in coordination between timing of rapid-acting insulin administration and meal ingestion may result in hypoglycaemia. However, guidelines regarding in-hospital use of insulin analogues are few. The safety profile of insulin analogues is still not completely established in long-term clinical studies. Several studies have shown conflicting results with respect to the tumourigenic potential of this new class of agents. The clinical implications of these findings are not clear. Although novel insulin analogues are promising 'designer drugs' in our armamentarium to overcome some of the limitations of conventional insulin therapy, cost may be a limiting factor for some patients.
Effects of various n-3 lipid sources on fatty acid compositions in chicken tissues

Studies on the effects of feeding various sources of n-3 fatty acids on the fatty acid composition of lipids in edible tissues and lipoproteins in chickens were conducted. Commercial meat-type chicks were fed one of four dietary lipids: (1) linseed oil, (2) menhaden oil, (3) soybean oil, or (4) chicken fat, at 50 g/kg of the diet from hatch through 56 days. Chickens fed the polyunsaturated lipids, linseed oil, menhaden oil, and soybean oil, all had similar plasma and VLDL + LDL (very low density lipoproteins and low density lipoproteins) triacylglycerol levels all of which were lower than those for chickens fed chicken fat. The fatty acid compositions of the VLDL + LDL fractions and tissue lipids were similar to the dietary lipids fed. However, the fatty acid compositions of the abdominal fat pads and brains reflected de novo synthesis in addition to the influence of dietary lipids. The levels of 20:50 in tissue lipids of chickens fed linseed oil approached those levels found in chickens fed menhaden oil. Chickens fed linseed oil had the highest levels of polyunsaturates in tissues while those fed chicken fat had the lowest levels. Chickens fed soybean oil maintained the highest levels of 18:2n6 and 20:4n6 in tissue lipids. Both the linseed oil and menhaden oil treatments exhibited lower levels of 20:4n6 in tissue lipids compared with the soybean oil and chicken fat treatments. These data indicate that dietary n-3 lipid sources influence the fatty acid composition of tissues and can be effectively used to enrich chicken meat with n-3 polyunsaturated fatty acids.
A gibberellin-stimulated ubiquitin-conjugating enzyme gene is involved in alpha-amylase gene expression in rice aleurone.

A ubiquitin-conjugating enzyme (UBC) gene, induced by gibberellin (GA) within an hour, was identified in rice (Oryza sativa) seeds by the mRNA differential display technique. GA inducibility was confirmed by RNA hybridization. A full-length UBC cDNA clone and a genomic clone have been isolated and sequenced. The deduced amino acid sequence shares a significant identity with several known UBC sequences, which are probably involved in the pathway responsible for degrading short-lived regulatory proteins. In vivo transient assays using the UBC gene promoter, joined to the luciferase cDNA as the reporter gene, showed that the sequence located between positions 231 and 159 upstream of the transcription start site of this promoter is crucial for GA-dependent activation of the luciferase cDNA. Finally, trans-activation experiments indicated that this UBC gene is involved in gibberellin-stimulated α-amylase gene expression.
Velocity profiles measured on the windward slope of a transverse dune

Velocity gradients measured on the windward slope of a transverse dune show that flow acceleration strongly affects the turbulence structure of wind. Wind profiles measured below a height of 1.6m are nonlogarithmic and the altered nature of velocity profiles varies over the windward slope of a dune. These findings suggest that calculated values of shear velocity are largely dependent upon the height and location of wind speed measurements, as well as the strength of the prevailing wind. Moreover, if Bagnold-type transport equations are used to calculate rates of sand transport on a dune, wind speeds must be measured within 0.2 m of the dune surface. If wind speeds are measured above this height, the resulting errors in calculated shear velocity will manifest themselves as errors in calculated rates of sand transport. If rates of sand transport are derived from wind speeds measured above 0.2 m the calculated rates may underestimate sand transport on the windward face of a dune as a result of flow acceleration. In contrast, if a dune has a separate crest upwind of the brink, the expansion and subsequent deceleration of flow downwind from the crest may result in an overestimation of sand transport.
Modeling driver behavior during complex maneuvers

This paper focuses on the modeling of driver behaviors during maneuvers that involve tire saturation. Drifting maneuvers are performed by an expert driver on low friction surfaces. Driving data is recorded and used to aid the construction of two different driver models. The first model parallels the driver to a model predictive controller and the second model treats the driver as a switched linear state feedback controller. This paper compares the two approaches and presents a framework where the driver model is integrated into an autonomous controller in the form of an optimization problem.
PRIMARY PULMONARY COCCIDIOIDOMYCOSIS EXPERIMENTAL INFECTION WITH COCCIDIOIDES IMMITIS

1. The literature concerning inhalation infection with Coccidioides immitis is briefly reviewed. 2. A laboratory technique for exposing animals to inhalation of the spores of Coccidioides immitis is described. 3. Primary pulmonary infection was produced in 42 per cent of 72 animals exposed by this method. 4. No marked weight loss was apparent in the animals infected. 5. Skin tests with coccidioidin were not entirely satisfactory in diagnosis. Positive skin tests with coccidioidin were obtained in many of the infected animals, but inconsistencies occurred. 6. The gross and microscopic lesions are briefly described and illustrated.
Depth inferences from vertically imbedded cephalopods

Raup, D. M.: Depth inferences from vertically imbedded cephalopods. Vertically imbedded cephalopods are not uncommon in the fossil record. Experiments with modern Nautilus show that after death the shell cannot maintain a vertical orientation on the sea floor unless the depth is less than about 10 m. At greater depths, hydrostatic pressure causes flooding of the phragmocone sufficient to make the shell fall over. The depth limit applies whether the shell floats after death or not. Calculations made on data from six ammonite species indicate that the same depth limit can be applied to fossil coiled cephalopods. Vertical preservation can occur in deeper water only if the shell is vertically oriented upon impact and if the sediment is such as to trap the shell in that position.
Challenges of high vacuum pumping based on impact ionization and implantation processes

Electron impact ionization and ion implantation processes were performed in a miniature test chamber (0.7 cm 3 ) to investigate the possibility of high vacuum pumping. The test chamber can be connected to or isolated from a pressure-controlled vacuum chamber for precise control of the initial experimental conditions. Despite, ion implantation into the getter (confirmed by SIMS measurements) at quantities 50× of the gas phase molecules, the pressure of the chamber increased during operation of the field emitter array. This pressure rise can be attributed to outgassing of the surface adsorbed molecules due to electron bombardment.
Epithelial cell migration in the intestine of the young mouse.

Autoradiographs were made of sections of the duodenal region of the intestine from 3 stages of preweaning mice, sacrificed at intervals after injection of thymidine-3H. The results clearly show that significant cell migration does occur in the intestinal epithelium of the duodenum at stages when dramatic cytodifferentiative changes are taking place in this tissue. The rate of epithelial cell migration (in terms of distance, in μ-traveled in 48 hours) is, in all of the 3 preweaning stages examined, lower than in the adult duodenum. Although the villi elongate, reaching a length equivalent to that of adult villi by 20–24 days after birth. the rate of epithelial cell migration does not increase during the preweaning period. As the villi lengthen, the time required for a cell to migrate from the intestinal crypt to the villus tip becomes increasingly greater. The observations in this study tend to support the idea that the process of villus elongation prior to weaning is regulated in the mouse duodenum by variation of the rate of cell extrusion from the villus tip.
Dinucleotide binding to RNase probed with UV resonance Raman spectroscopy

Raman spectra are reported for ribonuclease and its complexes with the dideoxynucleotides dCpdC, dCpdA and dCpdG, using 240–250-nm excitation to enhance the purine and pyrimidine modes, as well as tyrosine and phenylalanine modes of the protein. Spectral perturbations associated with binding were examined via difference spectroscopy. Consistent with the crystal structure of CpA* bound to RNase, the 3′-cytidine was inferred to be hydrogen bonded to a protein donor via the N-3 ring atom, but not via the carbonyl O atom, since the 1526 cm−1 band shifts up on binding, as it does when aqueous CMP is protonated, and the CO stretch shifts from 1655 to 1670 cm−1, an effect attributable to polarization via the N-3 hydrogen bond. The effect of binding on the spectra of the 5′-purine rings is limited to intensity changes, an augmentation of the adenine 1578 cm−1 band and a diminution of the guanine 1330 cm−1 band, consistent with only weak interactions with the protein. Binding of dCpdC intensifies the 1615 cm−1 protein band, suggesting environmental changes for tyrosine or phenylalanine residues. No spectral perturbation was observed on mixing RNase with dGpdC or dGpdG, consistent with weak or non-specific binding of dinucleotides lacking a pyrimidine in the 3′-position.