cssi/SciSciGPT-SciSciNet huggingface dataset:
Influence of geometry upon crack healing rate in calcite

Crack healing experiments were conducted at 780°, 815°, and 850° C in dry carbon dioxide over periods of 0.5 to 1320 h on small penny-shaped cracks of known geometry in Stahl calcite. As observed by previous investigators, healing initiates with the formation of tubes around the leading edge of the crack, followed by the pinching off of spherical bubbles from these tubes. Pillars and peninsular structures formed and grew at cleavage steps and other surface irregularities, greatly accelerating the healing process in some cracks. The crack tip regression distance at constant temperature follows a simple power law in time; although, with the exception of one crack at 850° C, the time exponent systematically decreases from 0.59 at 780° C to 0.15 and 0.07 at 815° and 850° C, respectively. Only the largest exponent is consistent with existing theory: the two smaller time exponents are, as yet, unexplained. Healing rates are strongly inversely dependent upon crack aperture, in qualitative agreement with theory. For example, cracks with maximum apertures of less than 60 nm (6×10−8 m) healed completely in 0.5 to 25 h at 850° C; while fatter cracks, with maximum apertures of about 700 nm, showed very little healing after up to 1320 h at the same temperature. At 780° C, the functional dependence of healing rate upon crack aperture was consistent with several aspects of the present model.
Towards a unified model of language description

Abstract The frequent attempts of linguists to construct unified models of language have been made more difficult by different modalities of categorization to be found in the phenomena of language. In many well documented cases language is best described by means of discrete categories, while in other instances continual categorization is more appropriate. A model is proposed that can operate in either mode, depending on how its elements are configured. A unified network model is outlined that contains discrete sub-components and continual sub-components, the two types being interlocked in a single structure. This model is found to have advantages in its ability to provide extended coverage of semantic phenomena and to provide a natural explanation for grammatical phenomena.
Start-up noise in 3-D self-amplified spontaneous emission

The Self-Amplified-Spontaneous Emission (SASE) is receiving a renewed interest recently in connection with the proposal to build x-ray FEL facilities. A consistent theory of how the initial incoherent undulator radiation develops into an exponentially growing coherent signal was derived in 1-D case previously. How the theory could be extended to a 3-D case was also explained previously. In the case of the parallel electron beam, the problem was explicitly solved previously. In particular, the equivalent noise power was identified as the undulator radiation in one gain length. In this paper, we study how the result should be modified when the electrons` angular divergence is taken into account. We find that the equivalent noise power is the portion of the undulator power within the coherent phase space area, a result that should have been expected.
Statistical presentation and analysis of ordered categorical outcome data in rheumatology journals

Objective To assess the appropriateness of presentation of summary measures and analysis of ordered categorical (ordinal) data in three rheumatology journals in 1999, and to consider differences between basic and clinical science articles. Methods Six hundred forty-four full-length articles from the 1999 editions of 3 rheumatology journals were evaluated for inclusion of an ordinal outcome. Articles were classified as basic or clinical science, and the appropriateness of presentation and analysis of the ordinal outcome were assessed. Chi-square tests were used to evaluate difference in percentages. Results Ordinal outcomes were identified in 175 (27.2%) of 644 articles. Only 69 (39.4%) had appropriate data presentation, and 111 (63.4%) had appropriate data analysis. Appropriate presentation was seen less commonly in the basic science rather than the clinical science articles, but differences in the occurrence of appropriate analysis were not seen. Conclusion Ordinal data are common in rheumatology articles, but presentation usually does not conform to recommended guidelines.
Sharp magneto-absorption resonances in the vortex state of Bi2Sr2CaCu2O8+δ

Abstract We have observed sharp resonances in the absorption of microwave radiation (30 to 50 GHz) in the vortex state of Bi 2 Sr 2 CaCu 2 O 8+δ . The unusual dispersion and temperature dependence suggest the excitation of an electronic mode strongly coupled to the vortex lattice.
The Application of Self-Efficacy Principles to Audiologic Rehabilitation: A Tutorial

Purpose The purpose of this tutorial is to provide a comprehensive overview of the self-efficacy framework and its application to audiologic rehabilitation. Method A literature review was conducted...
A framework based approach for unified detection of Aspect Weaving Problems

In Aspect-Oriented Programming (AOP), a crosscutting concern is extracted from a base program and is modularized into a new construct called aspect. The aspect is weaved back to the program to incorporate the crosscutting behaviors. Many semantic problems, referred to as Aspect Weaving Problems (AWPs) in this paper, could be introduced in the aspect weaving process. The AWPs have been independently defined using different modeling approaches for their detections. In practice, it is difficult for AOP developers to detect these problems, because they have to switch between different tools/methods. This is a time consuming and error-prone process. Consequently, it could increase the production costs of Aspect-Oriented development. This paper proposes a taxonomy of the AWPs to clearly define and classify the problems. Based on the taxonomy and a unified modeling approach to detect the AWPs, a conceptual analysis framework for the AWPs is also proposed. The framework aims at the integration of the unified AWPs detection capabilities into legacy aspect weavers by reusing (adapting) the modeling approach for various AOP languages.
Characterization of thymidine adducts formed by acrolein and 2-bromoacrolein

Thymidine was permitted to react with the known mutagens acrolein and 2-bromoacrolein under physiological conditions. The products of these reactions were separated by HPLC and characterized by UV, FAB/MS, electrospray MS, 1H NMR and chemical transformation. The reaction with acrolein gave one major product, N3-(3''-oxopropyl)thymidine, which is unstable in aqueous solution and was reduced with sodium borohydride to the corresponding alcohol. Reaction with 2-bromoacrolein yielded the unstable intermediate, N3-(2''-bromo-3''-oxopropyl)thymidine, and two stable products, the diastereomers of N3-(2''-hydroxy-3''-oxopropyl)thymidine, which are slowly transformed to N3-(2''-oxo-3''-hydroxypropyl)thymidine. Reactions with both mutagens proceed most rapidly at pH 9.2, less rapidly at pH 7.4, and no products are found at pH 4.2. Stable adducts found in the reaction of 2-bromoacrolein were also identified in reactions with single-strand oligodeoxynucleotides using a sensitive, selected ion monitoring GC/MS procedure.
Ground- and Excited-State Aggregation Properties of a Pyrene Derivative in Aqueous Media

The aggregation properties of 4-(1-pyrene)butanoate in aqueous media have been quantitatively investigated. For the pyrene chromophore ground state, the monomer−dimer equilibrium was monitored using NMR methods, yielding a dimerization constant of 150 M-1 for pyrenebutanoate in alkaline water. In addition, the excited-state aggregation was studied by time-resolved emission spectroscopy. The excimer formation constant in water, which represents the equilibrium established by interaction of excited- and ground-state species, was determined to be 1.6 × 104 M-1 (about 100-fold larger than the ground-state dimerization constant). The role of solvent polarity and the influence of an aromatic cosolvent were examined in order to determine the types of interactions that contribute to the driving force for aggregation. The ground-state aggregation propensity of pyrenebutanoate was significantly diminished upon addition of methanol or pyridine to aqueous solutions, indicating that hydrophobic and/or π-stacking inter...
Effects of Changing Jaw Height on F1 during Babble: A Case Study at 9 Months.

An empirical gap exists in our understanding of the extent that mandibular kinematics modulate acoustic changes in natural babble productions of infants. Data were recorded from a normal developing 9-month-old infant. Mandibular position was tracked from the infant during vowel and canonical babble. Linear predictive coding analysis was used to track estimates of formant center-frequency for F1. For each sample, a correlation coefficient was computed between changes in jaw height and formant history for F1. A Mann–Whitney rank sum test reached significance for differences among coefficients for vowel and canonical babble. Coefficients for vowel babble productions were nearest to −1 with a median of r = − 0.76, showing the strongest relationship between jaw position and formant history, while the median for canonical babble coefficients was r = − 0.54, indicating greater contribution of the tongue and lips. This 9-month-old infant exhibited plasticity for coordinating the jaw, tongue and lips among bab...
The adsorption of large proteins in electrofocusing on immobilized pH gradients: I. Protein specificity and dependence on Immobiline and carrier ampholyte concentrations.

Phycoerythrin, ferritin, urease, β-galactosidase and thyroglobulin, with molecular masses in excess of 200 kDa, adsorb and consequently fail to migrate to, and focus at, their pI positions in electrofocusing in immobilized pH gradients at a total Immobiline concentration of 20 mM while they do focus normally in pH gradients formed by carrier ampholytes. The addition of carrier ampholytes (pH range 3.5–9.5) at concentrations of 0.1 to 5 % to the Immobiline-containing gels reduces adsorption (desorbs) some but not all of the 5 proteins at specific Immobiline concentrations. The adsorption is not due to water redistribution and consequent reduction in gel porosity; nor is it due to conductivity minima across the pH gradient. The hypothesis that the presence of oligomeric Immobiline contributed to the protein adsorption is the subject of the accompanying report.
Phenolic profiles of Andean purple corn (Zea mays L.)

Qualitative and quantitative high performance liquid chromatography with diode array detection (HPLC-DAD) was performed to characterize the presence of phenolic compounds in Andean purple corn. Phenolic compounds were analyzed by separating them in two main fractions: a water fraction (WF) and an ethyl acetate fraction (EAF). The WF rich in anthocyanins revealed the presence of cyanidin-3-glucoside, pelargonidin-3-glucoside and peonidin-3-glucoside. The respective acylated anthocyanin glucoside forms of these compounds were also detected following alkaline hydrolysis. The EAF was composed of phenolic acids such as p-coumaric, vanillic acid, protocatechuic acid, flavonoids such quercetin derivatives and a hesperitin derivative. Alkaline and acid hydrolysis of the EAF revealed the presence of p-coumaric and ferulic acid as main components in four bound hydroxycinnamic acid forms present in the ethyl acetate fraction.
A clinical trial of escalating doses of flumazenil for reversal of suspected benzodiazepine overdose in the emergency department

Study objective: To determine if flumazenil, when used in doses higher than those currently recommended, could reverse the effects of a benzodiazepine (BDZ) overdose in patients who might not otherwise respond and whether the higher dose was associated with increased adverse effects. Design: Multicenter, randomized, double-blind, placebo-controlled, balanced, with parallel groups. Open-label flumazenil administration was available if a patient failed to respond or became resedated. Setting: Sixteen emergency departments in the United States. Population: Patients presenting to the ED with clinically significant signs and symptoms of a known or suspected BDZ overdose. Interventions: Patients were randomized to receive 10 mL/min of placebo or flumazenil (1 mg/10 mL) each minute for ten minutes. If there was no response, up to 3 mg of open-label flumazenil could be administered. Measurements and main results: Of 170 patients enrolled, 87 received flumazenil and 83 received placebo. The demographic characteristics of both groups were comparable. Ten minutes after the beginning of study drug infusion, patients were evaluated using the Clinical Global Impression Scale (CGIS), Glasgow Coma Scale (GSC), and Neurobehavioral Assessment Scale (NAS). The mean ± SD CGIS score at ten minutes for BDZ-positive patients was 1.41 ± 0.72 for patients who received flumazenil and 3.41 ± 0.91 for the placebo group ( P Conclusion: Flumazenil rapidly and effectively reverses the clinical signs and symptoms of a BDZ overdose. Most patients will respond to 3 mg or less, but a small number may require a higher dose for reversal of clinical symptoms. Patients with concomitant tricyclic antidepressant overdose may be at risk for developing seizures.
Solubilization of atractyloside-sensitive ADP (ATP) binding activity of rat liver mitochondria.

Summary Treatment of rat liver mitochondria with the nonionic surfactant Brij 56 yields a non-sedimentable supernatant fraction containing over 60 percent of the original atractyloside-sensitive ADP(ATP) binding activity and a sedimentable (membrane) fraction showing atractyloside-insensitive ADP binding. The supernatant fraction exhibited no atractyloside-sensitive binding of AMP, GDP, or CDP. Atractyloside-sensitive binding of ADP was not inhibited by oligomycin, antimycin A, 2,4-dinitrophenol, or azide. The atractyloside-sensitivity of ADP binding was lost on heating. The properties of the non-sedimentable ADP (ATP) binding factor agree closely with those of the ADP-ATP translocase of the inner mitochondrial membrane.
Corrections to Kinetic Measurements Taken on a Disk Electrode

Below the limiting current, the rotating disk electrode has a nonuniform current distribution. When the nonuniformities are not explicitly accounted for, errors in values of kinetic parameters determined through measurements on a disk can result. In this analysis, valid for Tafel kinetics, correction factors are obtained as a function of the dimensionless average current density. It is assumed that ohmic corrections are made by the interruption of current. The results indicate that, under certain conditions, the errors are negligible and that the disk geometry, despite its nonuniformities, is adequate for the investigation of systems characterized by Tafel kinetics.
Linkage of type II and type III cystinuria to 19q13.1: codominant inheritance of two cystinuric alleles at 19q13.1 produces an extreme stone-forming phenotype.

Cystinuria, a renal tubule disease affecting urinary cystine excretion with or without kidney stone formation, previously was mapped to chromosome region 2p.21. Mutations in the gene SLC3A1 or NBAT, the reported candidate gene for cystinuria at 2p.21, have been demonstrated in individuals with the autosomal recessive Type I cystinuria phenotype. Recently, the Type III cystinuria phenotype was mapped to chromosome region 19q13.1. Here we report a kindred of 39 persons in two families of cystinurics, Types II and III, that support linkage to 19q13.1 and exclude 2p.21. Based on a dominant model of inheritance, two-point analysis of the entire pedigree produced a maximum lod score (Z max ) of 3.82 at marker D19S425. Multipoint analysis yielded a lod score of 4.96 at this marker, and a resultant lod score of 5.90 using a codominant model of inheritance. Furthermore, a candidate gene interval of 8.9 cM, flanked by markers D19S225 and D19S223, was obtained using multipoint and haplotype analyses. Thus, this kindred demonstrates the linkage of Type II cystinuria to 19q13.1 and confirms the linkage of Type III cystinuria at 19q13.1 while excluding the marker D19S225 that was previously included in the critical interval.
Islet neoformation in tissue culture

Abstract We have devised a tissue culture system that permits de novo formation of islets. Neonatal rat pancreata are enzymatically dissociated into single cells. The cell suspension is filtered through polyester cloth with 20 μm pores to exclude cell aggregates as well as preformed islets and a single cell suspension is then plated into tissue culture dishes at a density precluding reaggregation. Pancreatic cells proliferate forming numerous colonies of epithelioid cells. After a confluent monolayer, cells proliferate into a third dimension, the space occupied by the culture medium. Third dimensional proliferation occurs from basal monolayers of epithelioid colonies. At about 9 days in culture, numerous hillocks are visible that are spaced at about 1 mm from one another. Islets are observed to bud from the hillock surfaces. In 1 μm-thick sections, secretion granules are detected with the light microscope in some islet cells. With the electron microscope three basic cell types are seen. One peripherally located cell type is sparsely granulated and appears to be a precursor cell. The other peripherally located cell type shows a homogenous population of secretion granules characteristic of A-cells. The third cell type is found in the interior of islets containing granules characteristic of B-cells. Islet cells, but not hillock cells, react immunocytochemically for insulin and glucagon. The cultures secrete 2 to 10-fold the amounts of glucagon present in fresh medium. It is concluded that differentiation of A- and B-cells occurs in neoformed islets.
Prevention of Depression and Anxiety in Patients with Cardiovascular Disease

Depression and anxiety are common in patients with cardiovascular disease (CVD). Depending on the time and method of assessment, depression occurs in 9-27% of patients, and anxiety is nearly universal in patients who have had an acute myocardial infarction (MI), at least during hospitalization. Depression has a major impact on mortality, morbidity and functional recovery and there is evidence that treating depression may improve outcome. While few studies have examined risk factors for depression in patients with CVD, the risk factors for depression identified in other clinical populations, such as previous history of depression, are undoubtedly relevant to CVD patients. Our data suggest that women are much more likely to be depressed than men, and to remain so in the course of recovery. Few strategies have been evaluated for primary prevention of depression or anxiety, even in the general population, and no studies have been undertaken in patients with CVD. While primary prevention of depression in postM...
Spectral Edge Frequency as a Simple Quantitative Measure of the Maturation of Electrocortical Activity

The feasibility of using spectral edge frequency (SEF) as a single quantitative measure of the maturation of electrocortical activity is demonstrated in a large number of fetal lambs studied throughout the 3rd trimester. A total of 43 electrocortical recordings obtained from 23 fetal lambs ranging from 116-140 d were subjected to power spectral analysis using the fast Fourier transform. Spectral edge frequency was calculated as the frequency below which 90% of the power resides. The SEF was found to be highly sensitive in identifying the transition between high-voltage slow-activity and low-voltage fast-activity electrocortical activity. By 125 d, the distribution of SEF clearly showed two distinct populations, a low SEF with peak values ranging from 3-9 Hz; and a high SEF (SEFH) with values ranging from 13-23 Hz. Increase in gestational age was associated with a progressive increase in SEFH, which can be described by the linear function (SEF = 0.53GA-51.3). This progressive increase in SEFH reflects the gradual acquisition of faster frequencies. In contrast, low SEF declined with age before 130 d, but then stabilized at 4 Hz throughout the rest of gestation. As a result, there was a gradual increase in the separation between SEFH and low SEF as a function of gestational age.
CHIRAL SURFACE STATES IN THE BULK QUANTUM HALL EFFECT

In layered samples which exhibit a bulk quantum Hall effect (QHE), a two-dimensional (2d) surface ``sheath" of gapless excitations is expected. These excitations comprise a novel 2d chiral quantum liquid which should dominate the low temperature transport along the field (z-axis). For the integer QHE, we show that localization effects are completely absent in the ``sheath", giving a metallic z-axis conductivity. For fractional filling $\nu =1/3$, the ``sheath" is a 2d non-Fermi liquid, with incoherent z-axis transport and $\sigma_{zz} \sim T^3$. Experimental implications for the Bechgaard salts are discussed.
COMMERCIAL BANK PRICE DISCRIMINATION AGAINST SMALL LOANS: AN EMPIRICAL STUDY*

THE BUSINESS LOAN SURVEYS made by the Federal Reserve Board' reveal consistently that commercial bank loans of smaller sizes carry higher interest rates than do larger loans. Since size of loans and size of firm are highly correlated, this inverse relationship between interest rates and size of loans apparently has led many observers to conclude that banks discriminate against small businesses.2 It is reasoned that small businesses have fewer sources of funds available to them and hence have more inelastic demand curves for loans from a particular bank lender than have large businesses. The banks are thought to "take advantage" of this situation by charging higher interest rates on small loans than on large loans. An alternative hypothesis is that the observed differential between interest rates charged on large and small loans is due to a differential in the marginal costs of lending and risk between large and small loans. The elasticity of demand for loans faced by a bank is believed to be the same whether it is derived from large or small loans.3 Then, as one can demonstrate with familiar price theory analysis, higher marginal costs of lending and risk on small loans (if they exist) should be reflected in higher rates charged on these loans if the bank does not price discriminate against large loans.4 To demonstrate this alternative hypothesis, it is necessary not only to show that the marginal cost of lending and risk is higher for small than for large loans, but also to show that the difference in marginal costs is sufficient to explain the difference in marginal earnings.5 Thus, estimates of marginal earnings, marginal lending costs, and the marginal cost of risk per $100 change in the size of loans, with the effect of other relevant factors taken into account, are presented in this study. Data for 1959 and 1960 and 1961 (three cross sections) were analyzed by means of multiple regression analysis. The coefficients estimated were consistent among the cross sections.
Niche-based projections of wetlands shifts with marine intrusion from sea level rise: an example analysis for North Carolina

Climate change is affecting world systems in many ways, of which one important dimension is sea level rise. This implication, however, has not heretofore been incorporated powerfully in analyses of biodiversity consequences of climate change, for lack of effective means of (1) modeling the degree and extent of marine intrusion into terrestrial habitats, and (2) anticipating dispersal-mediated shifts in natural systems (species, ecosystems, etc.). In this paper, recent developments in modeling marine intrusion over complex coastal landscapes are integrated with an adaptation of ecological niche modeling for estimating ‘niches’ of natural systems to anticipate sea level rise effects on them in an appropriate biological framework. This novel series of steps is illustrated with a worked example of wetlands systems and associated species and communities along the coast of North Carolina, but the methodology is novel for anticipating sea level rise-mediated shifts in vegetation types in many coastal systems.
Observing hydrogen induced deformations in palladium thin-films

We directly measured the nanoscale dynamics of hydrogen induced lattice expansion and deformation of palladium thin films in-situ. These results provide several key material parameters needed for designing high performance optical hydrogen sensors.
Reporting by Physicians of Impaired Drivers and Potentially Impaired Drivers

Physicians routinely care for patients whose ability to operate a motor vehicle is compromised by a physical or cognitive condition. Physician management of this health information has ethical and legal implications. These concerns have been insufficiently addressed by professional organizations and public agencies. The legal status in the United States and Canada of reporting of impaired drivers is reviewed. The American Medical Association's position is detailed. Finally, the Bioethics Committee of the Medical Society of the State of New York proposes elements for an ethically defensible public response to this problem.
Role Definitions and Organizational Citizenship Behavior: The Importance of the Employee's Perspective

A survey of 317 clerical workers demonstrated that employees differed in what they defined as in-role and extra-role behavior, that these differences were related to commitment and social cues, and...
The structure of the dense core region in transient diesel sprays

Intermittent and highly transient dense diesel sprays were investigated using two-dimensional laserlight scattering and transmission techniques to decipher the internal spray structure. The experiments were conducted at maximum injection pressures ranging from 19 to 32 MPa using an electronic diesel injector with a single-hole nozzle. The experiments involved the imaging of the unperturbed structure of the dense core region of a full-cone intermittent diesel spray on photographic film at high resolution and the simultaneous measurement of laser sheet transmission along the centerline of the spray by an array consisting of 2048 diodes. At all injection pressures, line-of-sight laser sheet transmission measurements showed that the dense core region is fragmented very near to the nozzle exit, about 25–30 nozzle diameters downstream, and perhaps much closer. Further downstream from this location, the transmission measurements and simultaneous 90° scattering images revealed that the structure has an intermittent appearance with pockets of dense spray separated by relatively void regions. Two-dimensional images displayed a highly atomized spray structure beyond 50 nozzle diameters downstream, with no indication of an intact liquid core for the range of injection pressures studied. After eliminating the secondary scattering present by applying a low-pass filter and subtracting the filtered image from the original image, it was demonstrated for enlarged views of the spray that the scattering is from randomly spaced point sources, which were interpreted as droplets, rather than liquid columns, ligaments, or large blobs of fuel. It seems that pressure-atomized and fully pulsed round liquid sprays have a significantly different near-field structure than their steady counterparts. These findings, along with the recent work of others, are inconsistent with the existence of a long (on the order of 100 nozzle diameters or more) intact liquid core in unsteady diesel sprays.
Cyanide anion binding by a triarylborane at the outer rim of a cyclometalated ruthenium(II) cationic complex.

As part of our ongoing interest in the design of boron-based cyanide anion receptors, we have synthesized a triaryl borane decorated by a cationic Ru(II) complex and have investigated its anion binding properties. This new borane, [(2,2′-bpy)Ru(κ-C,N-2-(dimesitylborylphenyl)pyridinato)]OTf ([2]OTf), binds both fluoride and cyanide anions in organic solvents to afford 2-F and 2-CN whose crystal structures have been determined. UV−vis titrations in 9/1 CHCl3/DMF (vol.) afforded K(F−) = 1.1(±0.1) × 104 M−1 and K(CN−) = 3.0(±1.0) × 106 M−1 indicating that [2]+ has a higher affinity for cyanide than for fluoride in this solvent mixture. These elevated binding constants show that the cationic Ru(II) complex increases the anion affinity of these complexes via Coulombic and inductive effects. The UV−vis spectral changes which accompany either fluoride or cyanide binding to the boron center are similar and include a 30 nm bathochromic shift of the metal-to-ligand charge transfer band. This shift is attributed to a...
The Cys154 → Gly Mutation in LacY Causes Constitutive Opening of the Hydrophilic Periplasmic Pathway

The lactose permease of Escherichia coli (LacY) is a highly dynamic membrane transport protein, while the Cys154-->Gly mutant is crippled conformationally. The mutant binds sugar with high affinity, but catalyzes very little translocation across the membrane. In order to further investigate the defect in the mutant, fluorescent maleimides were used to examine the accessibility/reactivity of single-Cys LacY in right-side-out membrane vesicles. As shown previously, sugar binding induces an increase in reactivity of single-Cys replacements in the tightly packed periplasmic domain of wild-type LacY, while decreased reactivity is observed on the cytoplasmic side. Thus, the predominant population of wild-type LacY in the membrane is in an inward-facing conformation in the absence of sugar, sugar binding induces opening of a hydrophilic pathway on the periplasmic side, and the sugar-binding site is alternatively accessible to either side of the membrane. In striking contrast, the accessibility/reactivity of periplasmic Cys replacements in the Cys154-->Gly background is very high in the absence of sugar, and sugar binding has little or no effect. The observations indicate that an open hydrophilic pathway is present on the periplasmic side of the Cys154-->Gly mutant and that this pathway is unaffected by ligand binding, a conclusion consistent with findings obtained from single-molecule fluorescence and double electron-electron resonance.
Dinoflagellate neurotoxins related to saxitoxin: Structure and latent activity of toxins B1 and B21

Abstract Toxins B1 and B2 from cultured dinoflagellates of the genus Protogonyaulax are shown to be the carbamoyl-N-sulfo derivatives of saxitoxin and neosaxitoxin, the structures confirmed by synthesis from the corresponding decarbamoyl toxins.
Minimized tolerance to the suppressive effects of CCK8 on operant responding

This study was designed to determine if tolerance to cholecystokinin octapeptide (CCK8) could be prevented or minimized by spacing injections, and if an appetitive operant conditioning paradigm provides a sensitive baseline to test the effects of CCK8. Male Sprague—Dawley rats were trained to press a lever for water according to a fixed-interval 60-sec schedule of reinforcement. After response rate stabilized, rats were given a series of CCK8 (0.04 mg/kg, ip) injections spaced several days apart. The first injection of CCK8 produced complete response suppression during the 30-min test session, while later injections produced partial or complete suppression. Thus, tolerance to CCK8, as measured by operant response rate, may be minimized if injections are appropriately spaced.
Partial information systems and the Smyth powerdomain

The dual of the join semilattice of proper compact Scott open subsets of a domain D is called the Smyth powerdomain of D. The Smyth powerdomain is used in programming semantics as a model for demonic nondeterminism. In this paper, we introduce the concept of partial information systems; and, as an application, show that the Smyth powerdomain of any domain can be realized in terms of the sub partial information systems of the domain’s corresponding information system.
Interaction between functionalized gold nanoparticles in physiological saline

The interactions between functionalized noble-metal particles in an aqueous solution are central to applications relying on controlled equilibrium association. Herein, we obtain the potentials of mean force (PMF) for pair-interactions between functionalized gold nanoparticles (AuNPs) in physiological saline. These results are based upon >1000 ns experiments in silico of all-atom model systems under equilibrium and non-equilibrium conditions. Four types of functionalization are built by coating each globular Au144 cluster with 60 thiolate groups: GS–AuNP (glutathionate), PhS–AuNP (thiophenol), CyS–AuNP (cysteinyl), and p-APhS–AuNP (para-amino-thiophenol), which are, respectively, negatively charged, hydrophobic (neutral-nonpolar), hydrophilic (neutral-polar), and positively charged at neutral pH. The results confirm the behavior expected of neutral (hydrophilic or hydrophobic) particles in a dilute aqueous environment, however the PMF curves demonstrate that the charged AuNPs interact with one another in a unique way—mediated by H2O molecules and an electrolyte (Na+, Cl−)—in a physiological environment. In the case of two GS–AuNPs, the excess, neutralizing Na+ ions form a mobile (or ‘dynamic’) cloud of enhanced concentration between the like-charged GS–AuNPs, inducing a moderate attraction (∼25 kT) between them. Furthermore, to a lesser degree, for a pair of p-APhS–AuNPs, the excess, neutralizing Cl− ions (less mobile than Na+) also form a cloud of higher concentration between the two like-charged p-APhS–AuNPs, inducing weaker yet significant attractions (∼12 kT). On combining one GS– with one p-APhS–AuNP, the direct, attractive Coulombic force is completely screened out while the solvation effects give rise to moderate repulsion between the two unlike-charged AuNPs.
Settlement and transport of benthic invertebrates in an intermittent upwelling region

We monitored settlement of sea urchins (Strongylocentrotus spp.) and crabs (primarily Cancer spp.) and concurrent physical variables at Bodega Marine Laboratory (BML) and Salt Point (northern California) from April through August 1992. Upwelling favorable winds led to lower temperatures, higher salinities, and lower subsurface pressures at BML, while periods of relaxation from upwelling typically caused a lagged reversal of each of these trends. This response to relaxation was due to a combination of alongshore and onshore flow of near-surface water at this site. Crab settlement was significantly correlated with the rate of temperature increase, corresponding to relaxation events. In contrast, sea urchins settled primarily during an unusual relaxation event which possibly involved remote forcing. Sea urchin and crab settlement were negatively correlated. Possible reasons include residence in different water masses, different biomechanical characteristics, and predation by crab larvae on sea urchin larvae. The time-course of settlement at Salt Point was similar to that at BML for both species groups.
The Complexity of Immersion Education: Teachers Address the Issues

The purpose of this study was to enlist practitioners in language immersion programs in the identification and elaboration of issues and challenges in immersion language teaching. Through focus groups and extensive individual interviews, 6 elementary Spanish-language immersion teachers in 3 school settings (a suburban full-immersion school and 2 inner-city magnet programs—1 partial and 1 full immersion) served as informants. Five major themes emerged: the primacy of language, the balance between language and content, assessment, the spectrum of learners in immersion programs, and the sociopolitical context of immersion schooling. Within each of these themes, teachers described the particular challenges of immersion teaching and illuminated the complexity of immersion classrooms on a microlevel. In a complex setting where the learning of curricular content and second language acquisition are expected to develop concurrently, teachers are in a unique position to add to our knowledge of immersion schooling.
A Calibrated Phase and Amplitude Control System for a 1.9 GHz Phased-Array Transmitter Element

A system is proposed to allow the phase and amplitude of a signal to be accurately set and regulated over process and power supply variations. It uses a variable gain amplifier (VGA) in conjunction with the phase shifter to compensate for the variable losses of the phase shifter and simultaneously provide a means of adjusting the amplitude of the signal. The system has been fabricated in a 0.18 ?m CMOS process, and operates at 1.9 GHz. The phase can be set with 5 bits of control over a 240° range and the amplitude can be varied over a 20 dB range. The feedback loops reduce the variation in |S 21| across the phase control range from 12.1 to 0.4 dB. For a changing power supply voltage the feedback loops reduce the maximum phase deviation from 28° to 7° , and across different test chips the maximum standard deviation over the phase control range is reduced from 12° to 3°.
The dynamics of group codes: Dual abelian group codes and systems

Fundamental results concerning the dynamics of abelian group codes (behaviors) and their duals are developed. Duals of sequence spaces over locally compact abelian (LCA) groups may be defined via Pontryagin duality; dual group codes are orthogonal subgroups of dual sequence spaces. The dual of a complete code or system is finite, and the dual of a Laurent code or system is (anti-)Laurent. If C and C/sup /spl perp// are dual codes, then the state spaces of C act as the character groups of the state spaces of C/sup /spl perp//. The controllability properties of C are the observability properties of C/sup /spl perp//. In particular, C is (strongly) controllable if and only if C/sup /spl perp// is (strongly) observable, and the controller memory of C is the observer memory of C/sup /spl perp//. The controller granules of C act as the character groups of the observer granules of C/sup /spl perp//. Examples of minimal observer-form encoder and syndrome-former constructions are given. Finally, every observer granule of C is an "end-around" controller granule of C.
Engineering the Genome of Thermus thermophilus Using a Counterselectable Marker

Thermus thermophilus is an extremely thermophilic bacterium that is widely used as a model thermophile, in large part due to its amenability to genetic manipulation. Here we describe a system for the introduction of genomic point mutations or deletions using a counterselectable marker consisting of a conditionally lethal mutant allele of pheS encoding the phenylalanyl-tRNA synthetase α-subunit. Mutant PheS with an A294G amino acid substitution renders cells sensitive to the phenylalanine analog p-chlorophenylalanine. Insertion of the mutant pheS allele via a linked kanamycin resistance gene into a chromosomal locus provides a gene replacement intermediate that can be removed by homologous recombination using p-chlorophenylalanine as a counterselective agent. This selection is suitable for the sequential introduction of multiple mutations to produce a final strain unmarked by an antibiotic resistance gene. We demonstrated the utility of this method by constructing strains bearing either a point mutation in or a precise deletion of the rrsB gene encoding 16S rRNA. We also used this selection to identify spontaneous, large-scale deletions in the pTT27 megaplasmid, apparently mediated by either of the T. thermophilus insertion elements ISTth7 and ISTth8. One such deletion removed 121 kb, including 118 genes, or over half of pTT27, including multiple sugar hydrolase genes, and facilitated the development of a plasmid-encoded reporter system based on β-galactosidase. The ability to introduce mutations ranging from single base substitutions to large-scale deletions provides a potentially powerful tool for engineering the genome of T. thermophilus and possibly other thermophiles as well. IMPORTANCE Thermus thermophilus is an extreme thermophile that has played an important part in the development of both biotechnology and basic biological research. Its suitability as a genetic model system is established by its natural competence for transformation, but the scarcity of genetic tools limits the kinds of manipulations that can currently be performed. We have developed a counterselectable marker that allows the introduction of unmarked deletions and point mutations into the T. thermophilus genome. We find that this marker can also be used to select large chromosomal deletions apparently resulting from aberrant transposition of endogenous insertion sequences. This system has the potential to advance the genetic manipulation of this important model organism.
A convenient apparatus for vertical gel electrophoresis.

An apparatus is described incorporating gel mold, electrode chambers, and direct-contact cooling plates. It eliminates several steps in preparing and handling the gel, and permits use of either rigid (starch) of flexible (acrylamide) gels. Electrophoretic analyses can be completed in 2-4 hr. Examples are given of serum and hemoglobin electrophoretic patterns obtained.
Stocks are Special Too: An Analysis of the Equity Lending Market

With a year of equity loans by a major lender, we measure the effect of actual short-selling costs and constraints on trading strategies that involve short-selling. We find the loans of initial public offering (IPOs), DotCom, large-cap, growth and low-momentum stocks to be cheap relative to the strategies’ documented profits and that investors who can short only stocks that are cheap and easy to borrow can enjoy at least some of the profits of unconstrained investors. Most IPOs are loaned on their first settlement days and throughout their first months, and the underperformance around lockup expiration is significant even for the IPOs that are cheap and easy to borrow. The effect of short-selling frictions appears strongest in merger arbitrage. Acquirers’ stock is expensive to borrow, especially when the acquirer is small, though the major influence on trading profits is not through expense but availability.
A Case Study in the Applied Philosophy of Imaging: The Synaptic Vesicle Debate

Thinkers from a variety of fields analyze the roles of imaging technologies in science and consider their implications for many issues, from our conception of selfhood to the authority of science. In what follows, I encourage scholars to develop an applied philosophy of imaging, that is, to collect these analyses of scientific imaging and to reflect on how they can be made useful for ongoing scientific work. As an example of this effort, I review concepts developed in Don Ihde’s phenomenology of technology and refigure them for use in the analysis of scientific practice. These concepts are useful for drawing out the details of the interpretive frameworks scientists bring to laboratory images. Next, I apply these ideas to a contemporary debate in neurobiology over the interpretation of images of neurons which have been frozen at the moment of transmitter release. This reveals directions for further thought for the study of neurotransmission.
MEAN MONTHLY VALUES OF PRECIPITABLE WATER OVER THE UNITED STATES, 1946–561

Abstract Mean monthly values of precipitable water have been computed for radiosonde stations in the United States for the period 1946–56. The individual monthly values and an elementary statistical analysis are presented for 52 stations with data during all or part of the period.
Psychomotor slowing in HIV infection: a predictor of dementia, AIDS and death

The objective of this study was to determine if sustained decline in psychomotor speed tests is associated with an increased risk of progression to dementia, acquired immunodeficiency syndrome (AIDS), or mortality in human immunodeficiency virus (HIV)-1-infected homosexual men in the Baltimore site of the Multicenter AIDS Cohort-Study (MACS). Clinical and neuropsychological data were obtained on 291 HIV+ homosexual men seen semi-annually over a nine year period (1986-1994). A proportional hazards model was used to assess the predictive value of sustained psychomotor slowing (defined as a 2.0 standard deviation (s.d.) decline in performance on either the Symbol Digit Modalities test or Trailmaking test at two consecutive evaluations). Time-dependent co-variates included in the model were sustained psychomotor slowing, number of attended visits, CD4+ lymphocyte count, hemoglobin and antiretroviral medication use. HIV+ participants with and without sustained psychomotor slowing were compared. Outcome variables were the development of dementia, AIDS and death. HIV+ subjects with sustained psychomotor slowing had an increased hazard of dementia (Risk ratio (RR) = 5.0, P = 0.008), AIDS (RR = 2.4, P = 0.02), and death (RR = 2.0, P = 0.04). A similar analysis using sustained cognitive decline in one domain from a more extensive neuropsychological test battery failed to show any predictive value. Sustained decline in psychomotor performance in HIV infection was predictive of dementia, AIDS and death. This brief neuropsychological test battery may be useful for early detection of HIV+ individuals with a poorer prognosis who may benefit from more aggressive treatment to prevent HIV dementia.
Low-voltage continuous time filters based on OTAs and Miller integrators

An approach to implement low-voltage continuous time filters using simple OTAs and Miller integrators is presented. The technique allows direct translation of system block diagram into a CMOS circuit implementation using differential pairs as OTAs and gain stages as Miller Integrators. A efficient compensation technique to cancel excess phase in Miller integrators is discussed. A high frequency compensated CMOS universal filter structure is discussed and experimentally verified.
Reconsidering the Common Good in a Business Context

In our contemporary post-modern context, it has become increasingly awkward to talk about a good that is shared by all. This is particularly true in the context of mammoth multi-national corporations operating in global markets. Nevertheless, it is precisely some of these same enormous, aggrandizing forces that have given rise to recent corporate scandals. These, in turn, raise questions about ethical systems that are focused too myopically on self-interest, or the interest of specific groups, locations or cultures. The obvious traditional alternative to moral bellybutton gazing is the common good, which challenges the modern business enterprise to realize non-instrumental values that can only be attained in our life together. The common good dictates that leadership should be judged, first of all, according to moral criteria rather than professional competence. It helps correct the distorted prioritization of the maximization of profit in every business decision, recognizing that businesses have a multitude of rights and responsibilities, and the common good reminds us that the first of these is not always profit-making.
Historical Amnesia: The Humphrey-Hawkins Act, Full Employment and Employment as a Right*

Economist William A. Darity has proposed a federal job guarantee with decent wages for all job seekers, an idea with deep, but largely forgotten, roots in US history.The article briefly explores some New Deal job-creation efforts and President Franklin Roosevelt’s proposal for an Economic Bill of Rights. It then focuses on two major attempts to secure full employment through legislation. The Full Employment Bill of 1945 was defeated; the compromise, the Employment Act of 1946 did not have full employment as its goal. After years of struggle, a much-weakened Humphrey-Hawkins Full Employment and Balanced Growth Act of 1978 passed, but then was violated and virtually ignored. Full employment shifts power from capital to labor, so major opposition can be expected from efforts to obtain it. Proponents need more power and a strong movement, including at the grassroots level, pushing for jobs for all--not just jobs for me or my group. Publicizing the benefits of past job programs and reintroducing the idea of a decent-paying job as a right are suggested, as well as making decent jobs for all the center of economic policy. This requires a fundamental break with neoliberalism and reallocating political power away from big business and Wall Street toward middle and working-class people and the working- and non-working poor.