cssi/SciSciGPT-SciSciNet huggingface dataset:
Dissociation of odor and taste in baitshyness.

The functions of odor and taste in food-illness aversions were dissociated experimentally. If on one trial taste is followed hours later by illness then that taste becomes aversive to the rat. In contrast, odor alone does not become aversive unless it is followed immediately and repeatedly by illness. Mucosally anosmic rats are equal, if not superior, to controls in acquisition of flavor-illness aversions and noise-shock suppression, but inferior in the neophobic response to new flavors. Olfactory bulbectomized rats are inferior in both tasks, as well as neophobia, indicating a general integrative bulbar function. Taste afferents coverging to the nucleus solitarius along with fibers from the viscera and area postrema play the primary role in adjusting the palatability of foods. Olfactory afferents projecting to the limbic system mediate neophobia and approach-withdrawal responses to food.
Studies of Electron Transitions Using Solid He Pressure Techniques

Studies of the pressure dependence of the Fermi surface of metals have proven useful in simplifying the details of the electronic structure of a large number of metals and semimetals in the past few years. Efforts have centered on: (1) the testing of band theoretical models or descriptions of the metal, and (2) studies of electron transitions or changes in the topology of the Fermi surface (FS), the subject of this discussion. Low-temperature pressure studies provide the best method for probing these topology changes because either temperature or alloying tends to smear out effects of these purely electronic transitions. There is a hierarchy of electron transitions of which the simplest Situation is the electron or Lifshitz transition [1]. This is a change in FS topology with no change in the crystal structure and no change in the interatomic spacing. The next step in the hierarchy is a change in FS topology accompanied by a change in volume, but no change in structure. This class includes the “mixed valence” and “electron promotion” situations found in an increasing number of narrow band systems which are currently receiving an enormous amount of attention. Included in this class are many of the metal-insulator and metal-semiconductor transitions. Finally, there is the third tier in the hierarchy where the topology change in the Fermi surface is accompanied by (or results from, depending on what is thought to be driving the transition) a change in both structure and volume. In this discussion, emphasis will be placed on the “simplest” Situation, the Lifshitz transition, where it is possible in several cases to follow directly the changes in the Fermi surface by use of deHaas-van Alphen or high field magnetoresistance techniques.
Searches for low-energy counterparts of gamma-ray bursters

The results of six studies concerning the identification of low-energy counterparts of gamma-ray bursters (GRBs) are reported. From these results, it is concluded that the near-infrared observations of GRBs from IRAS pose serious difficulties for several GRB models. No precedent or plausible explanation is found for the optical flash detected on February 8, 1984 by Pedersen et al. (1984) other than that the flash originated on a GRB. The star in the middle of the 1944 optical transient error box has an ultraviolet excess which is significant at the 95 percent confidence level, a result which strongly suggests that the object is indeed the quiescent GRB optical counterpart. If true, then GRBs are probably low-mass contact binaries caused by thermonuclear or accretion instabilities at distances of roughly 1 kpc.
Radionuclide imaging of angiotensin II type 1 receptor upregulation after myocardial ischemia-reperfusion injury

The renin-angiotensin system (RAS) mediates proapoptotic, profibrotic, and proinflammatory processes in maladaptive conditions. Activation after myocardial infarction may initialize and promote cardiac remodeling. Using a novel positron-emitting ligand, we sought to determine the presence and time course of regional myocardial upregulation of the angiotensin II type 1 receptor (AT1R) and the blocking efficacy of various anti-RAS agents. Methods In male Wistar rats (n = 31), ischemia-reperfusion damage was induced by 20- to 25-min ligation of the left coronary artery. The AT1R blocker (11)C-2-butyl-5-methoxymethyl-6-(1-oxopyridin-2-yl)-3-[[2-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-3H-imidazo[4,5-b]pyridine ((11)C-KR31173) was injected intravenously at different times until 6 mo after surgery and sacrifice. Autoradiography, histology, and immunohistochemistry were performed for ex vivo validation. Additional in vivo PET was conducted in 3 animals. A second series of experiments (n = 16) compared untreated animals with animals treated with oral valsartan (50 mg/kg/d), oral enalapril (10 mg/kg/d), and complete intravenous blockage (SK-1080, 2 mg/kg, 10 min before imaging). Results Transient regional AT1R upregulation was detected in the infarct area, with a peak at 1-3 wk after surgery (autoradiographic infarct-to-remote ratio, 1.07 ± 0.09, 1.68 ± 0.34, 2.54 ± 0.40, 2.98 ± 0.70, 3.16 ± 0.57, 1.86 ± 0.65, and 1.28 ± 0.27 at control, day 1, day 3, week 1, week 3, month 3, and month 6, respectively). The elevated uptake of (11)C-KR31173 in the infarct area was detectable by small-animal PET in vivo, and it was blocked completely by intravenous SK-1080. Although oral treatment with enalapril did not reduce focal tracer uptake, oral valsartan resulted in partial blockade (infarct-to-remote ratio, 2.94 ± 0.52, 2.88 ± 0.60, 2.07 ± 0.25, and 1.26 ± 0.10 for no treatment, enalapril, valsartan, and SK-1080, respectively). Conclusion After ischemic myocardial damage in a rat model, transient regional AT1R upregulation is detectable in the infarct area using (11)C-KR31173. Inhibitory effects of the clinical AT1R blocker valsartan can be identified, whereas blockage of upstream angiotensin-converting enzyme with enalapril does not affect AT1R density. These results provide a rationale for subsequent testing of AT1R-targeted imaging to predict the risk for ventricular remodeling and to monitor the efficacy of anti-RAS drug therapy.
The success factors of necessity immigrant entrepreneurs: In search of a model

This study focuses on the success factors of necessity immigrant entrepreneurs. It proposes a profile for the necessity immigrant entrepreneur as well as for the opportunity immigrant entrepreneur. It clarifies the concept of success for immigrant entrepreneurs and suggests that the concept of survival is more appropriate for the necessity immigrant entrepreneurs and should mainly be measured by the age of the business, while the traditional concept of success is relevant for the opportunity immigrant entrepreneur and can be measured by the usual quantitative performance indicators. Based on different existing theories, the study suggests a theoretical explanation of the survival factors of necessity immigrant entrepreneurs. This contributed to propose a theoretical model of survival factors of necessity immigrant entrepreneurs. This model, which represents the major contribution of this study, suggests five categories of survival factors: ethno-cultural factors, financial factors, managerial factors, psycho-behavioral factors, and institutional factors. © 2010 Wiley Periodicals, Inc.
Real-time generation of images with pixel-by-pixel spectra for a coded aperture imager with high spectral resolution

The capabilities ofa coded aperture imager are significantly enhanced when a detector with excellent energy resolution is used. We are constructing such an imager with a 1.1 cm thick, crossed-strip, planar detector which has 38 strips of 2 mm pitch in each dimension followed by a large coaxial detector. Full value from this system is obtained only when the images are ‘‘fully deconvolved’’ meaning that the energy spectrum is available from each pixel in the image. The large number ofenergy bins associated with the spectral resolution ofthe detector, and the fixed pixel size, present significant computational challenges in generating an image in a timely manner at the conclusion ofa data acquisition. The long computation times currently preclude the generation ofintermediate images during the acquisition itself. We have solved this problem by building the images on-line as each event comes in using pre-imaged arrays ofthe system response. The generation ofthese arrays and the use off ractional mask-to-detector pixel sampling is discussed. r 2003 Published by Elsevier Science B.V.
Evolution of homologous physiological mechanisms based on protein sequence data

Abstract 1. 1. Genetic duplications can give rise to homologous physiological mechanisms that include structurally related protein components. There are many such examples of related proteins within the human body. 2. 2. Evolutionary histories showing the origins and subsequent divergences of these distantly related proteins can be derived from the protein sequences and correlated with the functional characteristics of these proteins. 3. 3. The hormones related to glucagon provide an example of homology of physiological mechanisms and emergence of new functions subsequent to gene duplications. 4. 4. The proteins related to troponin C illustrate the participation of distantly related proteins in the same mechanism (muscle contraction), the relationship of proteins characteristic of a specialized tissue to proteins found in all eukaryote cells, and the correlation of genetic duplications with the evolutionary appearance of different types of muscle.
The Influence of Augmented Feedback on Skill Learning Depends on Characteristics of the Skill and the Learner

Augmented feedback is a common component of the communication between instructor and student in skill learning. In this article, the argument is made that the effective use of augmented feedback depends on understanding the various effects of augmented feedback on skill learning and the conditions characterizing the occurrence of each effect. Four distinct relationships between augmented feedback and skill learning are presented: Augmented feedback is necessary for learning some skills; it is not needed to learn some skills; for some skills it enables the learner to acquire the skill faster achieve a higher level of performance than would be possible without and it can be provided in such a way that it hinders skill learning. These four relationships are also discussed in terms of their implications for skill instruction.
Squamous cell carcinoma metastatic to neck from an unknown primary: The potential impact of modern pathologic evaluation on perceived incidence of human papillomavirus–positive oropharyngeal carcinoma prior to 1970†

Objectives/Hypothesis: From the 1950s through the 1960s, an unknown number of oropharyngeal squamous cell carcinomas (SCCs) presented with metastases to cervical lymph nodes from an unknown primary (SCCUP) and were not recognized as oropharyngeal in origin. At present, pathologic evaluation of SCCUP for human papillomavirus (HPV) improves discovery of occult oropharyngeal SCC and may partially explain increased incidence of HPV-positive oropharyngeal SCC. Study Design: Retrospective cohort study. Methods: A retrospective study of 13 cases of SCCUP diagnosed from 1956 to 1969 was performed. The probability of these cases of metastatic SCC to originate from the oropharynx was assessed by characterizing their morphology (keratinizing vs. nonkeratinizing) and HPV status by in situ hybridization and p16 immunostaining. Results: Two cases of nonkeratinizing SCC positive for HPV by in situ hybridization and p16 immunohistochemistry were identified. These cases were most likely of oropharyngeal origin. Conclusions: These two cases can be added to the other 15 cases of HPV-positive primary oropharyngeal SCC identified in our department from 1956 to 1969. When determining the incidence of HPV-positive oropharyngeal SCC before the 1970s, a correction factor of about +13% (2/15) accounting for modern pathologic workup of SCCUP during the last couple of decades may be appropriate. Laryngoscope, 2012
Involvement of oxidative stress in 3-nitropropionic acid neurotoxicity.

3-Nitroproprionic acid (3-NP) is a plant mycotoxin which produces selective striatal lesions in both experimental animals and in man. We previously found evidence that its neurotoxicity may be mediated by a secondary excitotoxic mechanism. In the present study we examined whether oxidative stress plays a role in the neurotoxicity of 3-NP in vivo. We examined whether the free radical spin traps α-phenyl- n-tert-butyl-nitrone (PBN), n-tert-butyl-α-(2-sulfophenyl)-nitrone (S-PBN) or 5,5-dimethyl-1-pyrroline- n-oxide (DMPO) could attenuate the neurotoxicity of 3-NP. Striatal lesions produced by systemic administration of 3-NP were protected by pretreatment with DMPO, but the toxicity of 3-NP was increased by PBN or S-PBN pretreatment. The content of 3-NP in the plasma was increased by S-PBN, but not by DMPO consistent with an effect of S-PBN on 3-NP metabolism. Lesions produced by systemic administration of 3-NP increased the production of hydroxyl free radicals (·OH) in the striatum as assessed by the conversion of salicylate to 2,3 and 2,5 dihydroxybenzoic acid (DHBA). These results provide direct evidence that free radicals play a substantial role in the neurotoxicity of 3-NP induced neuronal injury. Copyright © 1996 Elsevier Science Ltd.
Simulating a natural fire regime on an Atlantic coast barrier island complex in Florida, USA

Abstract The HFire fire regime model was used to simulate the natural fire regime (prior to European settlement) on Kennedy Space Center, Merritt Island National Wildlife Refuge, Canaveral National Seashore, and Cape Canaveral Air Force Station, Florida. Model simulations were run for 500 years and the model was parameterized using information generated from previously published empirical studies on these properties (e.g., lightning fire ignition frequencies and ignition seasonality). A mosaic pattern of frequent small fires dominated this fire regime with rare but extremely large fires occurring during dry La Nina periods. This simulated fire size distribution very closely matched the previously published fire size distribution for lightning ignitions on these properties. A sensitivity analysis was performed to establish which parameters were most influential and the range of variation surrounding empirically parameterized model output. Dead fuel moisture and wind speed had the largest influence on model outcome. A wide range of variance was observed surrounding the composite simulation with the least being 6% in total burn frequency and the greatest being 49% in total area burned. Because simulation modeling is the best option for fire regime reconstruction in many rapidly growing shrub dominated systems, these results will be of interest to scientists and fire managers for delineating the natural fire regime on these properties, the southeastern United States and other fire adapted shrub systems worldwide.
Use of diluted anion-exchange and hydrophobic properties in separating synthetic single-stranded oligodeoxyribonucleotides on mixed-ligand stationary phases

Mixed-ligand or “mixed-interaction” stationary phases are composed of bonded silanes possessing both ionic and hydrophobic character. The complex retention properties exhibited by these phases have been particularly useful in separating large biomolecules, such as synthetic single-stranded oligodeoxyribonucleotides. By isolating the individual properties of separate ligands present in mixed-ligand stationary phases a better understanding of the heterogeneous surface was sought. Specifically a dilute anion-exchange mixed-ligand phase of 5% surface coverage showed dramatically different selectivity for oligomers compared to hydrophobic stationary phases. Of particular interest was the increased selectivity observed in separating oligonucleotides differing on the 3′ end over conventional reversed-phases supports.
Inviscid instability of an unbounded shear layer: effect of surface tension, density and velocity profile

The inviscid temporal stability analysis of an unbounded shear layer of two fluids of different density is investigated. Two background velocity profiles are considered: the piecewise-linear profile and the more realistic error-function profile. The disturbance kinetic energy is analyzed to physically understand the mechanism that causes instability. The surface-tension effect is investigated extensively. Surface tension is found to destabilize the neutrally stable waves that exist when surface tension is absent. This surface-tension-induced unstable mode is generally weaker than the dominant mode and extremely less evident when the density and/or viscosity difference increases. Short-wavelength instability is observed with a background viscosity jump at the interface. A comparison between the two velocity profiles is presented. The piecewise-linear profile does not match the more realistic results obtained with the error-function profile in the short wavelength range, especially in nonhomogeneous shear-layer flows; however, the phase-speed results are in a good agreement with those of the error-function profile.
Coordination: Examining Weather as a “Matter of Concern”

I employ spoken and written discourse and extended excerpts from teleconferences between local, state, and federal officials in the midst of Hurricane Katrina to examine the term coordination as one powerful way of accounting for and pragmatically (re)constructing weather in crisis discourse. By means of discourse analysis, I find that the indexical term coordination is part of a metadiscursive vocabulary of disaster, and that, though it performs important social functions in the communication of accountability, authority, and redress, it has very little to do with communicating about weather itself. My conclusion presses for a discursive approach as a means of recovering and understanding social ontologies like weather and the way we materially organize around them as what Latour refers to “matters of concern.”
Existence of Nonequilibrium Steady State for a Simple Model of Heat Conduction

This paper contains rigorous results for a simple stochastic model of heat conduction similar to the KMP (Knipnis–Marchiori–Presutti) model but with possibly energy-dependent interaction rates. We prove the existence and uniqueness of nonequilibrium steady states, their relation to Lebesgue measure, and exponential convergence to steady states from suitable initial conditions.
Are nonlinguistic functions in Broca's area prerequisites for language acquisition? FMRI findings from an ontogenetic viewpoint

There is incomplete consensus on the anatomical demarcation of Broca's area in the left inferior frontal gyrus and its functional characterization remains a matter of debate. Exclusive syntactic specialization has been proposed, but is overall inconsistent with the neuroimaging literature. We examined three functional MRI (fMRI) datasets on lexicosemantic decision, tone discrimination, and visuomotor coordination for potential overlap of activation. A single site of convergent activation across all three paradigms was found in the left inferior frontal lobe (area 44/45). This result is discussed in the context of animal and human studies showing inferior frontal participation in visuomotor and audiomotor functions as well as working memory. We propose that Broca's area involvement in lexical semantics and syntax emerges from these nonlinguistic functions, which are prerequisites for language acquisition.
Mechanisms associated with corpus luteum lifespan in animals having normal or subnormal luteal function

Abstract The lifespan of the corpus luteum is influenced and can be manipulated by mechanisms (and their interactions) associated with secretions from the pituitary, ovary, uterus and conceptus. Luteal lifespan and secretion of progesterone are controlled by mechanisms which may enhance (luteotropic) or cause the demise (luteolytic) of the corpus luteum. Mechanisms controlling luteal function may be different among species. In addition, luteal function in some species has been characterized by subnormal function, either corpora lutea with short lifespans or corpora lutea with normal lifespans but decreased secretion of progesterone. Endocrine and cellular mechanisms which are associated with control of normal and subnormal luteal function in livestock species are discussed in this review.
Further Quantum Mechanical Evidence that Difluorotoluene Does Not Hydrogen Bond

Calculations were run on the methylated DNA base pairs adenine:thymine and adenine:difluorotoluene to further investigate the hydrogen-bonding properties of difluorotoluene (F). Geometries were optimized using hybrid density functional theory. Single-point calculations at the MP2(full) level were performed to obtain more rigorous energies. The functional counterpoise method was used to correct for the basis set superposition error (BSSE), and the interaction energies were also corrected for fragment relaxation. These corrections brought the B3LYP and MP2 interaction energies into excellent agreement. In the gas phase, the Gibbs free energies calculated at the B3LYP and MP2 levels of theory predict that A and T will spontaneously form an A:T pair while A:F spontaneously dissociates into A and F. Solvation effects on the pairing of the bases were explored using implicit solvent models for water and chloroform. In aqueous solution, both A:T and A:F are predicted to dissociate into their component monomers. Semiempirical calculations were performed on small sections of B-form DNA containing the two pairs, and the results provide support for the concept that base stacking is more important than hydrogen bonding for the stability of the A:F pair within a DNA helix.
Survival of shell-frozen, freeze-dried, and agar slant cultures of Pasteurella multocida

Summary Comparisons were made on the survival of P. multocida cultures after shell-freezing, freeze-drying, and maintenance on agar slants at various temperatures. Pasteurella multocodia suspended in a mixture of tryptose broth and skim milk and shell-frozen in a concentration of 4.45 × 104 colony-forming units (CFU) per ampule resulted in a survival of 58%. After the shell-frozen cultures were stored for 3 to 12 months at −62°C, an average survival of 47% and 43% CFU, respectively, was obtained. Cultures freeze-dried from the shell-frozen state at four different pressure levels and six drying times, following immediate reconstitution, resulted in an average survival of 21.2% CFU. After the freeze-dried cultures were stored for 3 and 12 months at 5°C, survival was reduced to an average of 12.5% and 0.6% CFU, respectively. Agar slant cultures qualitatively inoculated with P. multocida were viable after 7 months of storage at 25°C, 5°C, −23°C, and −62°C. No alterations in colonical or biochemical characteristics were noted for P. multocida cells which were shell-frozen or freeze-dried or those maintained on agar slants at 5°C, −23°C, and −62°C. However, after 2 months of storage at 25°C, agar slant cultures were observed to dissociate and provide a mixture of fluorescent, blue, and sectored colonies.
Reduction by atropine of phencyclidine hypertension and apneusis

Abstract The aim of this study was to assess the possible role of a central cholinergic component phencyclidine (PCP)-induced hypertension. Sprague-Dawley rats, lightly anesthetized with urethane, exhibited a dose related pressor response following 0.1–1.0 mg/kg PCP i.v. After i.v. atropine pre-treatment, the PCP dose-response curve was shifted to the right, and the magnitude of the pressor responses was reduced by about 50%. In addition, atropine reduced the incidence of apneusis, but had no effect on the bradycardia that accompanied the pressor responses. Methylatropine (i.v.) did not reduce the PCP pressor responses, nor did it prevent the apneusis induced by PCP. These results suggest that in addition to its direct pressor effects the activation of central cholinergic systems contribute significantly to the cardiovascular and respiratory toxicity induced by PCP.
Reciprocal influences between girls’ conduct problems and depression, and parental punishment and warmth: A six year prospective analysis

Although the reciprocal effects of parenting and child behavior have long been recognized, the emphasis of empirical study in the field of developmental psychopathology has been on parenting effects on children. For girls in particular, little is known about unique parenting effects on conduct problems in comparison to depression, or vice versa. In the current study, data from the large-scale (n = 2,451) Pittsburgh Girls Study were used to examine the reciprocal relations between parenting and child behavior over a six year period (child ages 7-12 years). Girls and their caregivers (85% of whom were biological mothers) were interviewed annually in their homes. Girls reported on symptoms of conduct disorder and depression, and caregivers reported on level of parent-child warmth and use of harsh punishment. The results of generalized estimating equation regression models demonstrated that both parenting behaviors were uniquely predictive of changes in girls' conduct problems and depressed mood. When the effects of race and poverty on these associations were controlled for, both parenting effects on girls' conduct problems remained significant, but only low parental warmth remained as a significant predictor of depressed mood. Girls' conduct problems, but not depressed mood, predicted changes in harsh punishment over time. The small effect of girls' depressed mood, on changes in parental warmth, was further weakened when socio-demographic factors were also included in the model.
Changes in Surface Runoff and Sediment Production after Repeated Rangeland Burns

Prescribed burning of vegetation may increase the potential for surface runoff and erosion. Changes in surface runoff and sediment production were evaluated with time following fall and spring burns at two different soil and vegetation type locations in southeastern Arizona. Rainfall simulations were conducted immediately after prescribed burns on four replicate areas and 1 yr later following a repeat burn on the same areas, and compared with paired unburned areas. The burn treatment and evaluation sequence was repeated in a second year on new areas to evaluate differences in years. After the first burn, runoff and sediment production on unburned and burned areas were similar within locations, and were greater at one location than the other. One location showed significantly more runoff and sediment production in the fall season on both unburned and burned areas after the first burn treatment. There was significantly greater runoff and sediment production from the burned areas after the second burn and the burned areas were now similar between locations. Runoff and sediment production for the fall season and for the second year on the 1-yr-old areas was higher at both locations, regardless of treatment. The increases in runoff and sediment production were greater from the burning than the season or year effects after 1 yr. The management implications for these locations and conditions are that, immediately after a rangeland burn, runoff and sediment production maybe unchanged, but within 1 yr significant increases can occur and significant seasonal and yearly differences may occur irrespective of a burn.
A multiscale bidirectional coupling framework

The lung is geometrically articulated across multiple scales from the trachea to the alveoli. A major computational challenge is to tightly link ODEs that describe lower scales to 3D finite element or finite volume models of airway mechanics using iterative communication between scales. In this study, we developed a novel multiscale computational framework for bidirectionally coupling 3D CFD models and systems of lower order ODEs. To validate the coupling framework, a four and eight generation Weibel lung model was constructed. For the coupled CFD-ODE simulations, the lung models were truncated at different generations and a RL circuit represented the truncated portion. The flow characteristics from the coupled models were compared to untruncated full 3D CFD models at peak inhalation and peak exhalation. Results showed that at no time or simulation was the difference in mass flux and/or pressure at a given location between uncoupled and coupled models was greater than 2.43%. The flow characteristics at prime locations for the coupled models showed good agreement to uncoupled models. Remarkably, due to reuse of the Krylov subspace, the cost of the ODE coupling is not much greater than uncoupled full 3D-CFD computations with simple prescribed pressure values at the outlets.
Multiangular approach in simultaneous retrieval of multiple aerosol optical properties

The POLarization and directionality of the Earth's Reflectances (POLDER) instrument onboard the Japanese ADEOS satellite offers unique possibilities for the retrieval of aerosol parameters with its polarization and multi-angular capability. In this study we examine a technique that simultaneously retrieves multiple aerosol parameters, namely asymmetry factor, single-scattering albedo, surface albedo, and optical thickness, using simulated multiangular POLDER reflectances. It is found that, for a typical illumination and observation geometry, these parameters can be retrieved rather accurately in the absence of noise. The retrieval accuracy deteriorates considerably, but remains tolerable, when a 0.1% white noise is present. The retrieval of these parameters in a more realistic atmosphere, i.e. with Rayleigh scattering, achieves similar accuracies, provided the assumption of the aerosol profile is valid. Indeed, this technique is sensitive to the aerosol profile assumed in the radiative transfer model.
Acidic pH of the lateral intercellular spaces of MDCK cells cultured on permeable supports.

The pH of the lateral intercellular space (LIS) of Madin-Darby canine kidney (MDCK) cell monolayers grown on permeable supports was investigated by microspectrofluorimetry using BCECF (2′,7′-bis(carboxyethyl)-5,6-carboxyfluorescein). The permeability of the support was selectively reduced by growing ZnAl-silicate crystals inside its pores. The diffusion of BCECF across the filter was sufficiently retarded to allow measurements of fluorescence in the LIS. The LIS pH and intracellular pH of the cells surrounding them were determined in HEPES-buffered solutions. When the perfusate pH was 7.4, the LIS pH was more acidic (7.06±0.02) and equaled the cytoplasmic pH (7.08±0.05). When perfusate was changed to pH 7.0 or 7.8, the LIS changed linearly by about half the magnitude of the perfusate pH. Intracellular pH followed LIS pH variations between perfusate pH 7.0 and 7.4 but was significantly higher when perfusate pH was 7.8. Tight junctional H+ permeability was undetectably low. The low steady-state pH in the LIS was not altered by inhibitors of acid transport or low temperature. Rapid perturbations of pH in the LIS showed that protons were not immobilized in the LIS. The acidic microenvironment within the LIS may be the result of buffering by the cell surface proteins.
Solution thermodynamic stability of complexes formed with the octadentate hydroxypyridinonate ligand 3,4,3-LI(1,2-HOPO): a critical feature for efficient chelation of lanthanide(IV) and actinide(IV) ions.

The solution thermodynamics of water-soluble complexes formed between Ce(III), Ce(IV), Th(IV) and the octadentate chelating agent 3,4,3-LI(1,2-HOPO) were investigated. Several techniques including spectrofluorimetric and automated spectrophotometric titrations were used to overcome the slow spontaneous oxidation of Ce(III) complexes yielding to stability constants of log β110 = 17.4 ± 0.5, log β11–1 = 8.3 ± 0.4 and log β111 = 21.2 ± 0.4 for [Ce(III)(3,4,3-LI(1,2-HOPO))]−, [Ce(III)(3,4,3-LI(1,2-HOPO)(OH)]2–, and [Ce(III)(3,4,3-LI(1,2-HOPO)H], respectively. Using the spectral properties of the hydroxypyridinonate chelator in ligand competition titrations against nitrilotriacetic acid, the stability constant log β110 = 41.5 ± 0.5 was determined for [Ce(IV)(3,4,3-LI(1,2-HOPO))]. Finally, the extraordinarily stable complex [Ce(IV)(3,4,3-LI(1,2-HOPO))] was used in Th(IV) competition titrations, resulting in a stability constant of log β110 = 40.1 ± 0.5 for [Th(IV)3,4,3-LI(1,2-HOPO))]. These experimental values ...
Identification of enzyme coupling sites with aromatic diazonium salts—A resonance Raman study

Abstract The coupling reaction of diazonium salts of aromatic compounds with the aromatic residues of proteins results in chromophoric covalent derivatives which yield strong resonance enhanced Raman spectra. The protein residues modified by these coupling reactions have been identified using the ν(NN) and ν(N-φ) vibrational bands in the resonance Raman spectra. Previous studies have established that diazoarsanilic acid couples with carboxypeptidase at tyrosine 248. The resonance Raman spectrum of arsanilazocarboxypeptidase was compared with spectra of arsanilazotyrosine and arsanilazohistidine model compounds; the results are consistent only with coupling at a tyrosine residue. This confirmation of the previously established site of modification establishes the utility of resonance Raman spectroscopy as a tool for identification of the site of covalent modification. To further investigate this approach, the diazonium salt of sulfanilamide (a site-specific reagent) was used to prepare a covalent coupling derivative of bovine carbonic anhydrase. The coupling reaction appears to have a stoichiometry of 1:1 and results in nearly complete loss of sulfanilamide binding capability and esterase activity. Comparison of the pH dependence of the resonance Raman spectra of sulfanilazocarbonic anhydrase with the spectra of sulfanilazotyrosine, sulfanilazohistidine, and sulfanilazotryptophan suggests that histidine is the site of modification of this new carbonic anhydrase derivative.
Interdisciplinary policy research in independent research centers

The growth of independent research centers after World War II reflected the federal government's concern for defense-related research and policy studies. These centers had more independence than government laboratories; greater emphasis on interdisciplinary, policy-oriented research than universities; and fewer conflicts of interest than industrial laboratories. The same factors carry over to interdisciplinary policy research in nondefense fields. The major problems of managing interdisciplinary team, selecting and motivating project leaders, maximizing institutional support, selecting the right projects and clients, and linking research to policy-making.
The Effects of Race and Social Distance on Obedience

Summary This study examined the willingness of white individuals to shock another person in the context of Milgram's teacher-learner paradigm as a function of the victim's race and appearance. The procedures were similar to Milgram's “subjects free to choose shock level” remote condition, and the apparatus was identical to that employed by Larsen. Ss were 31 female and 13 male undergraduates randomly selected from second term general psychology classes. Mean age of Ss was 19.9 years. Two confederates, one white and one black, played the role of “learners” throughout the study. Their appearances were manipulated to create two social distance conditions. The results indicated that white Ss showed a greater willingness to shock a black victim than a white victim and that the level of punishment delivered increased as the social distance between S and victim increased.
Drug development in spinal cord injury: what is the FDA looking for?

It has long been recognized that much of the post-traumatic degeneration of the spinal cord following injury is caused by a secondary injury process that occurs during the first minutes, hours, and days after spinal cord injury (SCI). A key biochemical event in that process is reactive oxygen-induced lipid peroxidation (LP). Indeed, the administration of a high-dose regimen of the glucocorticoid steroid methylprednisolone (MP) has been shown to inhibit post-traumatic LP in animal models of SCI, and to improve neurological recovery in spinal cord-injured humans. This resulted in the registration of high-dose MP for acute SCI in several countries, although not in the U.S. Nevertheless, this treatment quickly became the standard of care for acute SCI, since it was already on the U.S. market for many other indications. Subsequently, it was demonstrated that the nonglucocorticoid 21-aminosteroid tirilazad could duplicate the antioxidant neuroprotective efficacy of MP in SCI models, and evidence of human efficacy has been obtained. This article explains the process of the discovery, development, and Food and Drug Administration regulation of new drugs for SCI; reviews the past development of MP and tirilazad for acute SCI; identifies the regulatory complications involved in future SCI drug development; and suggests some promising therapeutic approaches that could either replace or be added to high-dose MP.
Engaging Health Professionals in Health Economics: A Human Capital Informed Approach for Adults Learning Online

The authors describe a Wikipedia-based project designed for a graduate course introducing health economics to experienced healthcare professionals. The project allows such students to successfully write articles on niche topics in rapidly evolving health economics subspecialties. These students are given the opportunity to publish their completed projects in Wikipedia. Despite the lack of conventional classroom incentives, the authors have found that the students generally choose to enter their final projects into Wikipedia. The authors explore the motivators for this behavior from the perspective of human capital development and reflect on the implications for enhancing economics education. Finally, they comment more generally on the value of assignments within graduate education that allow adult students to determine their degree of effort and reward along the intensive margin.
Nature and role of surface carbonates and bicarbonates in CO oxidation over RuO2

Base metal oxides have long been of interest as catalysts for oxidation of small molecules such as CO or NO, but practical applications are limited by surface poisoning processes. With growing interest in the oxidation activity of metal oxides, it is important to understand and ultimately to learn to bypass surface poisoning. RuO2, as a model metal oxide oxidation catalyst, is active for CO oxidation under UHV conditions but is deactivated by some surface poisoning processes at ambient pressures. In this work, we use plane-wave, supercell DFT calculations to characterize the structures of carbonate and bicarbonate on the RuO2(110) surface and determine their thermodynamic stability by constructing phase diagrams. We find that while a surface carbonate (CO2−3) is stable at low O2 pressures and high CO2 pressures, it is not stable under practical catalytic conditions. A surface bicarbonate (HCO−3) is more stable and deactivates the RuO2 surface over a wide range of CO2 and oxygen pressures in the presence of trace amounts of water. Therefore, bicarbonate is likely the species responsible for experimentally observed surface poisons that deactivates RuO2 during CO oxidation. OH* might also be a candidate responsible for surface poisoning when CO2 pressure is very low. This study demonstrates that surface poisoning is sensitive to reaction environments such as water and CO2 pressures.
Atg7 Induces Basal Autophagy and Rescues Autophagic Deficiency in CryABR120G Cardiomyocytes

Rationale:Increasing evidence suggests that misfolded proteins and intracellular aggregates contribute to cardiac disease and heart failure. Several cardiomyopathies, including the αB-crystallin R120G mutation (CryABR120G) model of desmin-related cardiomyopathy, accumulate cytotoxic misfolded proteins in the form of preamyloid oligomers and aggresomes. Impaired autophagic function is a potential cause of misfolded protein accumulations, cytoplasmic aggregate loads, and cardiac disease. Atg7, a mediator of autophagosomal biogenesis, is a putative regulator of autophagic function. Objective:To determine whether autophagic induction by Atg7 is sufficient to reduce misfolded protein and aggregate content in protein misfolding-stressed cardiomyocytes. Methods and Results:To define the gain and loss of function effects of Atg7 expression on CryABR120G protein misfolding and aggregates, neonatal rat cardiomyocytes were infected with adenoviruses expressing either wild-type CryAB or CryABR120G and coinfected with...
Water relations characteristics of competing singleleaf pinyon seedlings and sagebrush nurse plants

Drivas, E.P. and Everett, R.L., 1988. Water relations characteristics of competing singleleaf pinyon seedlings and sagebrush nurse plants. For. Ecol. Manage., 23: 27-37. Encroachment of singleleaf pinyon (Pinus monophyUa) into adjacent low sagebrush (Artemisia arbuscula) and basin big sagebrush (Artemisia tridentata ssp. tridentata) communities may be enhanced by the efficient use of limited water resources by tree seedlings. Seedlings and sagebrush nurse plants were monitored over two growing seasons to determine water-use patterns. Predawn xylem water potential of low sagebrush declined rapidly, reaching - 3.5 to - 5.5 MPa by late summer. Big sagebrush values dropped to -2.0 to -3.0 MPa during summer drought. The drop in sagebrush xylem water potential was related to the decline in soil water potential (r = 0.68 and 0.82 ). The change in pinyon predawn xylem water potential was moderate, declining to values of - 1.5 to - 2.5 MPa. An apparent diurnal threshold xylem water potential ( - 2.3 to - 3.0 MPa) that results in stomatal closure enables pinyon seedlings to maintain a seasonally stable xylem water potential. Water use by pinyon seedlings declined by 50 To from May to August in association with a reduction in stomatal conductance. Despite reduced stomatal conductance, sagebrush water use continued to increase during summer and reached levels up to five times greater (per unit leaf area) than associated pinyon. Pinyon seedlings appear to have greater drought avoidance than sagebrush nurse plants.
The spillover of hydrogen onto silica: IV. The use of scanning FTIR to follow spillover from a point source

Abstract The interphase transport of adsorbed species is referred to as spillover. A technique was developed to quantify the rate of surface diffusion across silica after spillover from platinum. The source of spillover is isolated on the accepting silica surface and the concentration of spillover deuterium is measured as a function of time and distance from the source. The rate of surface diffusion of hydrogen across silica is rapid and is detected 1 cm from the source within a few minutes. Spillover and not surface diffusion seems the controlling rate in the combined spillover and diffusion processes. The transport seems to be facilitated by “associated” hydroxyls on the surface. Only a limited number of sites are involved and the rate of transport decreases as saturation is approached.
Michael Polanyi's Social/Political Order: Design for a Society of Explorers

Abstract Michael Polanyi's fascinations throughout his lifetime were threefold: (1) science—specifically physical chemistry; (2) philosophy—specifically epistemology and ontology; and (3) political society, understood, in the British tradition, to include economics. In developing his recommendations for political society, Polanyi draws broadly upon insights and even concepts from his experiences and reflections in both science and philosophy. His search for meaning in all of his philosophical works provides for him the definition of what he considers the most important human endeavor and is that which the political order must strive to encourage and protect. In addition, the gratification he found in the collegiality and conviviality of scientific research, conducted most productively in what Polanyi identified as “societies of explorers,” suggested to him the diverse groups—as in science, “polycentrically” ordered—and engaged in all kinds of productive activities that came to represent, for him, the gras...
Effect of Electrical Double Layer on the Performance of Nanometer Interdigitated Electrodes

To investigate the effect of electrical double layer (EDL) on the electrical current response of interdigitated electrodes (IDEs), we performed a finite element based computational simulation of the electrochemical kinetics and mass transport occurring at nano-scale IDEs. Results show the presence of the EDL affects the voltammetric response of nano-IDEs. This effect varies with the gap spacing in the IDEs, the charge valence of the reactant, and the concentration of supporting electrolyte due to the overlap of diffuse and diffusion layers as well as the overlap of the diffuse layers of the generator and collector.
Nitroreductase from Salmonella typhimurium: characterization and catalytic activity

The biocatalytic activity of nitroreductase from Salmonella typhimurium (NRSal) was investigated for the reduction of α,β-unsaturated carbonyl compounds, nitroalkenes, and nitroaromatics. The synthesized gene was subcloned into a pET28 overexpression system in E.coli BL21 strain, and the corresponding expressed protein was purified to homogeneity with 15% protein mass yield and 41% of total activity recovery. NRSal showed broad substrate acceptance for various nitro compounds such as 1-nitrocyclohexene and aliphatic nitroalkenes (alkene reductase activity), as well as nitrobenzene (nitroreductase activity), with substrate conversion efficiency of > 95%. However, the reduction of enones was generally low, proceeding albeit with high stereoselectivity. The efficient biocatalytic reduction of substituted nitroalkenes provides a route for the preparation of the corresponding nitroalkanes. NRSal also demonstrated the first single isolated enzyme-catalyzed reduction of nitrobenzene to aniline through the formation of nitrosobenzene and phenylhydroxylamine as intermediates. However, chemical condensation of the two intermediates to produce azoxybenzene currently limits the yield of aniline.
Ca2+-stimulated Ca2+ Oscillations Produced by the Ca2+-sensing Receptor Require Negative Feedback by Protein Kinase C

We examined the role of protein kinase C (PKC) in the mechanism and regulation of intracellular Ca(2+) concentration ([Ca(2+)](i)) oscillations elicited by an increase in the extracellular concentration of Ca(2+) ([Ca(2+)](e)) in human embryonic kidney 293 cells expressing the Ca(2+)-sensing receptor (CaR). Exposure to the PKC inhibitors bisindolylmaleimide I (GF I) or Ro-31-8220 converted oscillatory responses to transient, non-oscillatory responses, significantly reducing the percentage of cells that showed [Ca(2+)](i) oscillations but without decreasing the overall response to increase in [Ca(2+)](e). Exposure to 100 nm phorbol 12,13-dibutyrate, a direct activator of PKC, eliminated [Ca(2+)](i) oscillations. Addition of phorbol 12,13-dibutyrate at lower concentrations (3 and 10 nm) did not eliminate the oscillations but greatly reduced their frequency in a dose-dependent manner. Co-expression of CaR with constitutively active mutants of PKC (either epsilon or beta(1) isoforms) also reduced [Ca(2+)](i) oscillation frequency. Expression of a mutant CaR in which the major PKC phosphorylation site is altered by substitution of alanine for threonine (T888A) eliminated oscillatory behavior, producing [Ca(2+)](i) responses almost identical to those produced by the wild type CaR exposed to PKC inhibitors. These results support a model in which phosphorylation of the CaR at the inhibitory threonine 888 by PKC provides the negative feedback needed to cause [Ca(2+)](i) oscillations mediated by this receptor.