cssi/SciSciGPT-SciSciNet huggingface dataset:
Cochlear Frequency Tuning and Otoacoustic Emissions

Otoacoustic emissions (OAEs) evoked from the inner ear are the barely audible, signature byproduct of the delicate hydromechanical amplifier that evolved within its bony walls. Compared to the sounds evoked from the ears of common laboratory animals, OAEs from human ears have exceptionally long delays, typically exceeding those of cats, guinea pigs, and chinchillas by a factor of two to three. This review asks "Why are human OAE delays so long?" and recounts efforts to locate answers in the characteristics of mechanical frequency selectivity in the inner ear. The road to understanding species differences in OAE delay leads to the identification of new invariances and to the emergence of new questions.
The effects of granulocyte colony-stimulating factor on MR images of bone marrow

Granulocyte colony-stimulating factor (G-CSF) analogs such as filgrastim/pegfilgrastim are increasingly used to enhance neutrophilic recovery after chemotherapy. It is widely known that, physiologically, pegfilgrastim stimulates marrow mitotic activity and induces marrow reconversion from fatty to cellular. However, there is limited literature discussing the effects of pegfilgrastim on musculoskeletal magnetic resonance imaging, with the consensus that marrow reconversion secondary to pegfilgrastim therapy is easily confounded with a malignant process, especially in patients with a history of cancer. We attempt to discuss the expected changes and MRI findings after pegfilgrastim therapy through a summary of current literature. Additionally, we provide images from our own practice to support the previously established findings. G-CSF-stimulated reconversion can appear as patchy expansions of baseline hematopoietic marrow, but can also appear to be diffusely homogeneous, adding to its ambiguity. We conclude that using a baseline MRI, clinical information, and assessing sequential MRI changes in conjunction with pegfilgrastim therapy may aid the differentiation between benign and pathological change. We expand our discussion to include the effects of novel technologies, such as whole-body MRI, chemical shift imaging, and contrast agents in helping the distinction.
Long-term pain outcomes for recurrent idiopathic trigeminal neuralgia after stereotactic radiosurgery: a prospective comparison of first-time microvascular decompression and repeat stereotactic radiosurgery.

OBJECTIVE: Microvascular decompression (MVD) and stereotactic radiosurgery (SRS) are common surgical treatments for trigeminal neuralgia (TN). Many patients who receive SRS have pain recurrence; the ideal second intervention is unknown. The authors directly compared pain outcomes after MVD and repeat SRS in a population of patients in whom SRS failed as their first-line procedure for TN, and they identified predictors of pain control. METHODS: The authors reviewed a prospectively collected database of patients undergoing surgery for TN between 1997 and 2014 at the University of California, San Francisco (UCSF). Standardized data collection focused on preoperative clinical characteristics, surgical characteristics, and postoperative outcomes. Patients with typical type 1, idiopathic TN with ≥ 1 year of follow-up were included. RESULTS: In total, 168 patients underwent SRS as their first procedure. Of these patients, 90 had residual or recurrent pain. Thirty of these patients underwent a second procedure at UCSF and had ≥ 1 year of follow-up; 15 underwent first-time MVD and 15 underwent repeat SRS. Patients undergoing MVD were younger than those receiving repeat SRS and were more likely to receive ≥ 80 Gy during the initial SRS. The average follow-up was 44.9 ± 33.6 months for MVD and 48.3 ± 45.3 months for SRS. All patients achieved complete pain freedom without medication at some point during their follow-up. At last follow-up, 80% of MVD-treated patients and 33.3% of SRS-treated patients had a favorable outcome, defined as Barrow Neurological Institute Pain Intensity scores of I-IIIa (p < 0.05). Percentages of patients with favorable outcome at 1 and 5 years were 86% and 75% for the MVD cohort and 73% and 27% for the SRS cohort, respectively (p < 0.05). Multivariate Cox proportional hazards analysis demonstrated that performing MVD was statistically significantly associated with favorable outcome (HR 0.12, 95% CI 0.02-0.60, p < 0.01). There were no statistically significant predictors of favorable outcome in the MVD cohort; however, the presence of sensory changes after repeat SRS was associated with pain relief (p < 0.01). CONCLUSIONS: Patients who received MVD after failed SRS had a longer duration of favorable outcome compared to those who received repeat SRS; however, both modalities are safe and effective. The presence of post-SRS sensory changes was predictive of a favorable pain outcome in the SRS cohort.
Ordering in the mixed ZnGeN 2 -GaN alloy system: Crystal structures and band structures of ZnGeGa 2 N 4 from first principles

While ${\mathrm{ZnGeN}}_{2}$ and GaN are closely lattice matched and have almost equal band gaps around 3.5 eV, their band offset is of order 1 eV. This situation suggests that there could be an opportunity for tuning the band gap in the alloy system. In particular, we examine here the 50 at. % composition, ${\mathrm{ZnGeGa}}_{2}{\mathrm{N}}_{4}$. It is shown that there are two 16-atom unit cell ordered structures, with space groups $Pmn{2}_{1}$ and $P1n1$, that obey the octet rule, with each N bound to two Ga, one Zn, and one Ge. The $Pmn{2}_{1}$ structure is a superlattice along the orthorhombic $b$ direction of the ${\mathrm{ZnGeN}}_{2}\phantom{\rule{4pt}{0ex}}Pbn{2}_{1}$ structure, in which half the cell is replaced by GaN; consequently, octet-rule-preserving polytypes spanning the entire range of composition can be formed based upon this structure. Two other structures that do not obey the octet rule are also considered for comparison. These are superlattices consisting of 1/2 cell GaN and 1/2 cell ${\mathrm{ZnGeN}}_{2}$ along the orthorhombic $a$ or $c$ direction. By means of fully relaxed density functional calculations, we find that the structures that obey the octet rule have significantly lower total energy than the ones that do not. Detailed crystallographic data on these four structures: space group, lattice constants, relaxed Wyckoff positions, and predicted x-ray diffraction spectra, are provided. The lowest energy structure is found to have a negative energy of formation, comparable to those of ${\mathrm{ZnGeN}}_{2}$ and GaN. However, the mixing energy is slightly positive, indicating a tendency toward phase separation into ${\mathrm{ZnGeN}}_{2}$ and GaN even when only considering low energy octet-rule-preserving structures. The band gaps of the octet-rule-preserving structures, calculated using the quasiparticle self-consistent $GW$ method, are found to be slightly higher than those of ${\mathrm{ZnGeN}}_{2}$ and GaN. This result can be explained in terms of size quantization effects compensating the reduced interface band gap.
Influence of expected reward on perceptual decision making

Perceptual decision making is influenced by reward expected from alternative options or actions, but the underlying neural mechanisms are currently unknown. More specifically, it is debated whether reward effects are mediated through changes in sensory processing and/or later stages of decision making. To address this question, we conducted two experiments in which human subjects made saccades to what they perceived to be the first or second of two visually identical but asynchronously presented targets, while we manipulated expected reward from correct and incorrect responses on each trial. We found that unequal reward caused similar shifts in target selection (reward bias) between the two experiments. Moreover, observed reward biases were independent of the individual9s sensitivity to sensory signals. These findings suggest that the observed reward effects were determined heuristically via modulation of decision-making processes instead of sensory processing and thus, are more compatible with response bias rather than perceptual bias. To further explain our findings and uncover plausible neural mechanisms, we simulated our experiments with a cortical network model and tested alternative mechanisms for how reward could exert its influence. We found that our observations are more compatible with reward-dependent input to the output layer of the decision circuit. Together, our results suggest that during a temporal judgment task, the influence of reward information on perceptual choice is more compatible with changing later stages of decision making rather than early sensory processing.
The Replica-Symmetric Prediction for Random Linear Estimation With Gaussian Matrices Is Exact

This paper considers the fundamental limit of random linear estimation for i.i.d. signal distributions and i.i.d. Gaussian measurement matrices. Its main contribution is a rigorous characterization of the asymptotic mutual information (MI) and minimum mean-square error (MMSE) in this setting. Under mild technical conditions, our results show that the limiting MI and MMSE are equal to the values predicted by the replica method from statistical physics. This resolves a well-known problem that has remained open for over a decade.
GENOTYPIC AND PHENOTYPIC CHARACTERIZATION OF ENTERIC BACTERIA IN AN INTEGRATED POPULATION OF SWINE AND HUMANS

In two longitudinal studies, we examined the transmission dynamics of antimicrobial resistance (AMR) in an integrated, semi-closed population of humans and swine. A total of 1594 human and 1508 swine Escherichia coli (EC) and Enterococcus faecalis (EF) isolated from human wastewater and swine fecal samples were tested for antimicrobial susceptibility, for the presence of Class I integrons and gene cassettes that encode for AMR, and for the prevalence of van- comycin-resistant Enterococcus faecium (VRE). We showed that swine EC and EF had a higher prevalence of AMR than human isolates and that both swine and human EC had a low prevalence of Class I integrons. We isolated a total of 50 VRE from human wastewater samples and no VRE from swine samples. We concluded there was no apparent transfer of AMR from swine to human or vice versa, and that VRE may be more prevalent in the environment than previously thought. Introduction It is generally perceived by the medical community that antimicrobial resistance (AMR) in human infections is a consequence of sub-therapeutic antibiotic usage in animal produc- tion (Anderson, 1999). Because no definitive studies have determined this phenomenon, con- trolled epidemiologic studies with stable human and animal populations are needed to identify the transmission dynamics of AMR (Khachatourians, 1998). Scott et al., (2005) conducted a cross-sec- tional study in a uniquely integrated population of humans and swine to begin to address this need. Preliminary results suggested that occupational exposure of humans to swine did not appear to be associated with the prevalence of AMR in commensal fecal Escherichia coli (EC). The current study is a longitudinal continuation of the previous study in the same population (Scott et al., 2005). The objective of this study was to generate data over a two year period on the AMR phenotypic and genotypic profiles and potential AMR transmission dynamics of EC, Enterococcus faecalis (EF), and E. faecium in a semi-closed population of swine and humans.
Charge Distributions from Relativistic Form Factors

Position eigenvector matrix elements and highly local expectation values of the charge density field are examined in the relativistic domain to establish a more satisfactory notion of charge distribution than is customarily employed.
Keynote: Were You There When??

Since the early 1960s, the field of management information systems has experienced tremendous growth and its research community has formalized and flourished. Professor Ephraim R. McLean, Regents' Professor and George E. Smith Eminent Scholar's Chair -- "Eph" -- is a legend among scholars of information systems and in particular scholars in computer and people research. He has been a fixture at ACM SIGMIS CPR from its early beginnings in the 1970s. His keynote will provide a historical look at the foundations of the field, examine its enduring issues, and speculate about the future of research and practice.
Assessing Reliability of Big Data Stream for Smart City

Proliferation of IoT (Internet of Things) and sensor technology has expedited the realization of Smart City. To enable necessary functions, sensors distributed across the city generate a huge volume of stream data that are crucial for controlling Smart City devices. However, due to conditions such as wears and tears, battery drain, or malicious attacks, not all data are reliable even when they are accurately measured. These data could lead to invalid and devastating consequences (e.g., failed utility or transportation services). The assessment of data reliability is necessary and challenging especially for Smart City, as it has to keep up with velocity of big data stream to provide up-to-date results. Most research on data reliability has focused on data fusion and anomaly detection that lack a quantified measure of how much the data over a period of time are adequately reliable for decision-makings. This paper alleviates these issues and presents an online approach to assessing Big stream data reliability in a timely manner. By employing a well-studied evidence-based theory, our approach provides a computational framework that assesses data reliability in terms of belief likelihoods. The framework is lightweight and easy to scale, deeming fit for streaming data. We evaluate the approach using a real application of light sensing data of 1,323,298 instances. The preliminary results are consistent with logical rationales, confirming validity of the approach.
Cryogenic Correlative Single‑Particle Photoluminescence Spectroscopy and Electron Tomography for Investigation of Nanomaterials

Cryogenic single-particle photoluminescence (PL) spectroscopy has been used with great success to directly observe the heterogeneous photophysical states present in a population of luminescent particles. Cryogenic electron tomography provides complementary nanometer scale structural information to PL spectroscopy, but the two techniques have not been correlated due to technical challenges. Here, we present a method for correlating single-particle information from these two powerful microscopy modalities. We simultaneously observe PL brightness, emission spectrum, and in-plane excitation dipole orientation of CdSSe/ZnS quantum dots suspended in vitreous ice. Stable and fluctuating emitters were observed, as well as a surprising splitting of the PL spectrum into two bands with an average energy separation of 80 meV. In some cases, the onset of the splitting corresponded to changes in the in-plane excitation dipole orientation. These dynamics were assigned to structures of individual quantum dots and the excitation dipoles were visualized in the context of structural features.
Product-Form Loss Networks

A circuit-switched telephone network is depicted in Figure 5.1. It consists of a collection of switches and links, with each link containing a finite number of circuits. The links may use either analog or digital transmission.1 One or more adjacent links constitutes a route, and there may be more than one route joining a pair of switches.
Procedural Training in Pediatric Emergency Medicine Fellowship: What Are We Teaching and What Do Fellows Need to Learn?

Background Life-saving procedures are rarely performed on children in the emergency department, making it difficult for trainees to acquire the skills necessary to provide proficient resuscitative care for children. Studies have demonstrated that residents in general pediatrics and emergency medicine lack exposure to procedures in the pediatric context, but no studies exist regarding procedural training in pediatric emergency medicine (PEM). Although the Accreditation Council for Graduate Medical Education (ACGME) provides a list of procedures in which PEM fellows must be competent, the relevance of this procedure list to actual PEM practice has not been studied. Objectives This study sought to determine whether PEM fellowships currently provide sufficient exposure to the skills most relevant for practicing PEM physicians. Study design Data were collected via anonymous electronic survey from physicians who graduated from PEM fellowship between 2012 and 2016. Survey items measured respondents' comfort with performing critical procedures, and their perceptions of the necessity of knowing how to perform each procedure in their current practice environment. Results A total of 133 individuals responded to the survey. Respondents unanimously agreed that 18 of the 36 procedures required by the ACGME are necessary to know in their current practice environment. For the remaining 18 mandated procedures, there was significant disagreement among respondents both as to the necessity of the procedure in current practice and respondents' degree of comfort with performing each procedure. Conclusions Among recent PEM fellowship graduates, there is significant variation in comfort with performing ACGME-mandated procedures. These data highlight important opportunities for curricular enhancement in the procedural training of PEM physicians.
Modulation and dynamics of cell membrane heterogeneities.

Abstract Numerous studies provide evidence that the lipid bilayer of the plasma membrane contains lateral nanodomains, and that these are functionally important regulators of transmembrane cell signaling. Depending on their chemical composition and the biophysical mechanism bringing the lipids together, multiple types of nanodomains exist in the inner and the outer leaflet of the plasma membrane bilayer. In intact cells, these domains are smaller than the optical resolution limit of light microscopy and also highly dynamic. Recently, advanced fluorescence methods have provided data to characterize many biophysical and thermodynamic aspects of these nanodomains. In this review, we summarize the physicochemical determinants of nanodomain formation, stability and extent. Then, we detail how these nanodomains play a structural role by anchoring nucleation sites for the membrane cytoskeleton on the lipid bilayer. Further, we review the existing literature on mechanisms that modulate the nanodomain size and stability, both acute and chronic events. We conclude that regulation of the nanodomains distribution in the lipid bilayer of the plasma membrane is important for modulation of transmembrane signaling. However, only very few modulators of nanodomain stability and size have been quantified in cells, suggesting interesting directions for future studies.
Learning on the left: political profiles of Brandeis University: by Stephen J. Whitfield, Waltham, MA, Brandeis University Press, 2020, 581 pp., $40.00 (hardback), ISBN: 978-1-68458-001-8

For over forty years, Stephen J. Whitfield has written works on topics as varied as America’s Cold War Culture, critic Dwight Macdonald, radical theorist Scott Nearing, and selected Jewish-American...
On-chip assembly of silicon photonic band gap crystals

Summary form only given. Three-dimensional silicon photonic band gap crystals are obtained by combining planar self-assembly of colloidal spheres with standard silicon deposition techniques. This simple and inexpensive approach, which is compatible with conventional microelectronics fabrication, yields high refractive index inverted opals of controllable thickness that are integrated directly onto a silicon wafer. These photonic bandgap structures, which operate at telecommunications wavelengths, are planar single-crystals over large areas with very low defect densities.
Proximal sensing of vineyard soil and canopy vegetation for determining vineyard spatial variability in plant physiology and berry chemistry

Proximal sensing is used in vineyards to precisely monitor and manage spatial and temporal variability while reducing laborious and repetitive measurements. Soil electrical conductivity (EC) and canopy vegetation indexes are two frequently assessed variables with off-the-shelf sensors. In this study, the ecophysiological variability of a commercial vineyard comprising three varieties in three blocks, Cabernet-Sauvignon (CS), Cabernet franc (CF), and Petit Verdot (PV), was investigated. Random sampling was used to continuously assess spatial variability in plant physiology and berry composition. Soil EC and NDVI were also continuously monitored throughout the season. There was a noticeable spatial pattern in the normalised differential vegetation index (NDVI) in the vineyard and soil EC. The spatial pattern of NDVI can be partially elucidated by the season-long stem water potential (Ψstem), which was lowest in the CS block. However, leaf photosynthesis did not match this spatial pattern. The spatial distribution of NDVI and soil EC did not satisfactorily explain the spatial variations in yield components and berry chemistry. Principal component analyses (PCA) were performed resulting in a clear discrimination of each of the three cultivars. Soil EC showed a significant relationship with Ψstem integrals, total skin anthocyanins and tri- to di-hydroxylated flavonoids. In each cultivar block, soil EC showed some capability to be related to plant water status, and NDVI showed a relationship with yield. Overall, this study provided evidence of the spatial variability of grapevine physiology in a commercial vineyard with three cultivars. Also, it showed that the cultivar effect and uniform crop level management can diminish the efficiency of proximal sensing, thus weakening the relationship of soil and canopy indexes with plant physiology and berry chemistry. Nonetheless, our study showed that it is possible to apply temporal proximal sensing methods when assessing plant water status, primary metabolism, yield and berry secondary metabolism, which give an indication of the possibility of managing the spatial variability of both plant physiology and berry chemistry.
The Use of Tissue Engineering to Fabricate Perfusable 3D Brain Microvessels in vitro

Tissue engineering of the blood-brain barrier (BBB) in vitro has been rapidly expanding to address the challenges of mimicking the native structure and function of the BBB. Most of these models utilize 2D conventional microfluidic techniques. However, 3D microvascular models offer the potential to more closely recapitulate the cytoarchitecture and multicellular arrangement of in vivo microvasculature, and also can recreate branching and network topologies of the vascular bed. In this perspective, we discuss current 3D brain microvessel modeling techniques including templating, printing, and self-assembling capillary networks. Furthermore, we address the use of biological matrices and fluid dynamics. Finally, key challenges are identified along with future directions that will improve development of next generation of brain microvasculature models.
A new finite element and finite difference hybrid method for computing electrostatics of ionic solvated biomolecule

The Poisson-Boltzmann equation (PBE) is one widely-used implicit solvent continuum model for calculating electrostatics of ionic solvated biomolecule. In this paper, a new finite element and finite difference hybrid method is presented to solve PBE efficiently based on a special seven-overlapped box partition with one central box containing the solute region and surrounded by six neighboring boxes. In particular, an efficient finite element solver is applied to the central box while a fast preconditioned conjugate gradient method using a multigrid V-cycle preconditioning is constructed for solving a system of finite difference equations defined on a uniform mesh of each neighboring box. Moreover, the PBE domain, the box partition, and an interface fitted tetrahedral mesh of the central box can be generated adaptively for a given PQR file of a biomolecule. This new hybrid PBE solver is programmed in C, Fortran, and Python as a software tool for predicting electrostatics of a biomolecule in a symmetric 1:1 ionic solvent. Numerical results on two test models with analytical solutions and 12 proteins validate this new software tool, and demonstrate its high performance in terms of CPU time and memory usage. Propose special 7-box partition with one solute box surrounded by six solvent boxes.Define a finite element and finite difference hybrid PBE solver on the 7-box partition.Program PCG with multigrid V-cycle preconditioning for linear system on solvent box.Generate the 7-box partition and an interface-fitted mesh of solute box adaptively.Reduce the total CPU time of a finite element PBE solver up to 70% in protein tests.Verify the new hybrid PBE solver to be numerically stable in computing solvation free energy.
Long-term tillage impacts on soil organic matter components and related properties on a Typic Argiudoll

Abstract Soil organic matter affects a number of soil processes and properties. A better understanding of soil-profile distribution of organic matter components and related soil properties under long-term tillage systems is thus needed. The objective of this study was to evaluate the impacts of 33 years no-till (NT), double disk (DD), chisel (CH), and plow tillage (PT) under corn ( Zea mays L .)–soybean ( Glycine max L.) rotation on soil organic C (SOC), particulate organic matter (POM), pH, and wet aggregate stability to 100 cm soil depth on a Sharpsburg silty clay loam (fine, montmorillonitic, mesic Typic Argiudolls) in eastern NE. After 33 years, NT and DD management increased SOC by 1.2 times and mean weight diameter (MWD) of aggregates by 2 times compared with CH and PT at the 0–10 cm depth. At the 0–20 cm, NT had 1.1 times higher SOC concentration than CH and PT. When compared with data collected 24 years prior to this study, SOC at the 0–20 cm increased by 12.5% across NT, DD, and CH and by 2.7% for PT. No-till had 5 times higher total POM concentration than PT, 4.7 times higher than CH, and 2.4 times higher than DD at the 0–10 cm depth. However, at the 10–20 cm, PT had higher POM than other tillage systems, which is most probably due to mixing and burial of residues at the bottom of the plow layer. Soil pH did not differ among tillage treatments at the 0–10 cm, but it differed in this order: PT > CH > DD > NT at the 10–20 cm and PT = CH = DD > NT at the 20–40 cm depth. The lower pH under NT, DD, and CH in deeper soil depths may be due to the limited or no lime mixing in these systems compared with PT. When compared with data (pH 5) collected 33 years prior to this study, soil pH increased by 0.9 in NT, 1.4 in DD, 1.5 in CH, and 1.9 units in PT at 0–20 cm depth, probably due to surface application and incorporation of lime. Overall, 33 years of NT increased near-surface soil organic matter components and soil aggregation compared with the PT.
SU‐E‐T‐34: A Feasible Action Level System for DVH‐Based IMRT QA

Purpose: Gamma-based IMRT QA metrics have been shown to inadequately predict clinically relevant patient dose errors. In this study, we develop and evaluate an intuitive and feasible DVH-based IMRT QA action level system, which incorporates both physical and clinical considerations. Methods: VMAT plans from previously treated prostate (n=11) and brain (n=13) patients are analyzed. Treatment plans were created using Eclipse TPS and delivered using Varian’s Trilogy linac. Initial IMRT QA was performed using the ArcCHECK phantom. All plans passed gamma-based criteria (3%/3mm) with at least a 97% passing rate. To design and test the feasibility of the DVH-based IMRT QA metric, 3DVH software is used to process the QA data from the ArcCHECK measurement and predict the 3D distribution of dose delivered to the patient. This enables comparison of a standard set of clinically important DVH values between TPS calculations and that predicted by the QA process. A two-level system is implemented to determine the IMRT QA Result. Level 1 requires that QA predicted DVH values for the PTV and OARs fall within a physical tolerance generated by scaling the original planned dose uniformly by ±5%. If level 1 tolerance is exceeded, level 2 requires that the QA-predicted DVH values are within institutional normal tissue tolerances. OARs for prostate cases include bladder and rectum. OARs for brain cases include the lens, optic nerve, optic chiasm, and brainstem. Results: All analyzed QAs passed the proposed action levels, with prostate cases all satisfying physical tolerances. Ten brain cases had DVH values failing physical tolerances, but satisfying clinical tolerances. All DVHs failing physical tolerances are in low dose region. Conclusion: The proposed IMRT QA metrics represents a straightforward alternative to the gamma-based metric. It has the potential to better address both physical and clinical concerns that are specific to individual patients.
Dictyostelium discoideum: a New Method for Cloning in Liquid Medium

Abstract Dictyostelium discoideum can be cloned in droplets of liquid medium by a method that permits observation of the complete life cycle. This alternative to solidified media provides advantages in clonal analysis.
Science content and social context

Content analysts have made substantial progress in moving beyond the framework in which science news is assessed primarily in terms of accuracy and adequacy, but content-analytic studies of science...
Food preservatives and dental caries.

Abstract The use of food preservatives has increased enormously over the past several decades. Intuitively, constant ingestion of food preservatives (antimicrobials) could have a profound effect on the oral flora. Preservatives used range from antibiotics to the more commonly used weak acids, for example benzoates, propionates and sorbates. Weak acids reduce the acid tolerance of microorganisms, damage the properties of their cell membranes and exert their antimicrobial effect in a manner similar to that of fluoride. Results from laboratory- and animal-based investigations support the concept that food preservatives alone or in combination with fluoride could reduce the prevalence of dental caries and possibly other plaque related diseases of the mouth.
Millisecond Pulsar Spectra

A study of the flux density and component emission of four millisecond radio pulsars shows that on average millisecond radio pulsars have steeper spectra than slow period pulsars. The results of flux density measurements of four millisecond pulsars, PSRs 1620-26, 1821-24, 1855+09, and 1937+21, have been made to determine their spectral indices in the range between 425 MHz to 3 GHz. The four objects are shown to have indices that range from -1.3 to -2.6. The flux densities are compared with other measurements down to 10 MHz. None of the objects shows any indication of a sharp spectral break at low frequencies. An analytic pulse component model is developed for each object. A more detailed presentation of this work can be found in Foster, Fairhead, and Backer (1991).
Discipline, Shaming and Antisocial Attitude in Philadelphia Middle Schools

The U.S. school system has changed fundamentally in its basic approach to social control in recent decades, with harsh approaches to student discipline having increased in popularity despite data showing pronounced and steady declines in incidents of both school violence and juvenile delinquency. This study revisits a sample of students in the Philadelphia School District to examine how perceptions of school rules and administration are associated with antisocial attitudes among students who were recently disciplined. The analysis included measures of interdependency, shaming, and peer association derived from reintegrative shaming theory. Findings from multiple regression analysis show that students who perceived their sanction as reintegrative in the school context were less likely to hold antisocial attitudes. Implications of the findings are discussed.
Molecular detection of persistent Borrelia burgdorferi in the urine of patients with active Lyme disease.

Current diagnostic tests for Lyme disease (LD) are dependent upon the host serologic response and are insensitive early in infection and, possibly, following antibiotic therapy. We cloned a library of Borrelia burgdorferi 297 DNA and studied one clone, Ly-1, for its potential in diagnostic and pathogenic studies. Using pulsed-field electrophoresis, we demonstrated that Ly-1 is of chromosomal origin and estimated that the B. burgdorferi chromosome is approximately 1,100 kb in size. The 3.7-kb Ly-1 clone hybridizes with geographically diverse strains of B. burgdorferi. No cross hybridization occurs with DNA from human cells, Escherichia coli, Staphylococcus aureus, Clostridium difficile, or the closely related B. hermsii. We used a dot blot assay to detect 100 pg of B. burgdorferi DNA. We partially determined the nucleotide sequence of Ly-1 and used it to select and synthesize oligonucleotides for use in the polymerase chain reaction (PCR). Two different primer pairs were found to amplify DNA from nine geographically diverse isolates. We could detect 10 fg (less than 10 molecules) of B. burgdorferi or less than five spirochetes added to human urine. Finally, we were able to use the PCR to detect B. burgdorferi DNA in the urine of four of eight patients with suspected active LD (three with arthritis and one with neurologic manifestations), all of whom responded to antibiotic treatment. In contrast, those patients who were PCR negative either had inactive disease or had been appropriately treated and did not respond to additional antibiotics, and all four control urine specimens were PCR negative. We conclude that B. burgdorferi DNA can be sensitively detected by the PCR with the primers and methods we describe and that the urinary tract is a site of persistent infection in some cases of human LD, an observation of potential diagnostic and pathogenic importance. Images
14N nuclear quadrupole resonance in N-acetyl amino acids†

14N Nuclear quadrupole resonance (NQR) spectra of several N-acetyl amino acids and related compounds are reported and analyzed within the framework of the Townes and Dailey theory. The inductive effect of the chloroacetyl group on the nitrogen is discussed. A positive correlation between the π-σNC electron density at the nitrogen and the Taft inductive parameter σ* is observed, suggesting that the nitrogen π-charge density in the N-acetyl amino acids does not vary appreciably. NQR data for hippuric acid are compared to the 14N quadrupole parameters extracted from ENDOR data reported for X-irradiated hippuric acid.
On the dynamics of a class of optimum routing problems

Abstract A particular class of routing problems associated with demand actuated transportation systems requires the repeated regeneration of minimum or optimum routes as a part of the more general routing problem. The generation or regeneration of routes by methods other than classical minimum route solutions is discussed. A general system model for processing demands in a demand actuated transportation or routing system is presented and discussed.
Isotopic composition of lead in oceanic basalt and its implication to mantle evolution

New data are given in this report for (1) Pb isotopic compositions and U, Th, and Pb concentrations of basalts from the island of Hawaii; (2) redetermined Pb isotopic compositions of some abyssal tholeiites; and (3) U, Th, and Pb concentrations of altered and fresh abyssal basalts, and basalt genesis and mantle evolution are discussed. The Th/U ratios of abyssal and Japanese tholeiites are distinctly lower than those of tholeiites and alkali basalts from other areas. It is thought that these low values reflect a part of the mantle depleted in large ionic lithophile elements. Thus a mantle evolution model is presented, in which Th/U ratios of the depleted zone in the mantle have decreased to ∼2, and U/Pb ratios have increased, showing an apparent ∼1.5-b.y. isochron trend in the 207Pb/204Pb vs. 206Pb/204Pb plot. The Pb isotopic compositions of basalts from the island of Hawaii are distinct for each of the five volcanoes, and within each volcano, Pb's of tholeiites and alkali basalts are similar. An interaction between partially melted material (hot plume?) of the asthenosphere and the lithosphere is suggested to explain the trend in the Pb isotopic compositions of Hawaiian basalts.
Friendship Conceptions among Early Adolescents: A Longitudinal Study of Stability and Change:

Stability and change in early adolescents' friendship conceptions were examined in a one-year longitudinal study. Once during sixth grade, and again during seventh grade, 99 girls and 98 boys were asked to rate 14 items according to how important each item was for friendship. These items were grouped according to the results of a factor analysis into three clusters referred to as Commonality, Help/Support, and Intimacy. A multivariate analysis of variance, followed by planned comparisons and simple effects tests, revealed: (a) a decrese over time in the importance ascribed to the Commonality cluster; (b) a decrease over time in the boys' ratings on the Help/Support cluster, but no change in the girls' ratings on this cluster; (c) no change over time in the ratings on the Intimacy cluster; (d) higher ratings from the girls than the boys for the Intimacy and Help/Support clusters, with the differences on the Help/Support cluster becoming larger over time; and (e) relatively higher ratings for the Help/Suppo...
Alkaline gastritis following antrectomy--an elusive syndrome.

Editorial. Le diagnostic de gastrite alcaline ou de reflux alcalin est delicat, la decision de realiser une diversion «Roux en Y» importante. Des explorations precises sont necessaires
Nanocomposite Multilayer Film of a Ruthenium Metallodendrimer and a Dawson-Type Polyoxometalate as a Bifunctional Electrocatalyst

A pentaerythiritol-based metallodendrimer with four ruthenium(II) terpyridine units (RuDen) and a Dawson-type phosphotungstate, P2W18O626- (P2W18) are immobilized on a glassy carbon electrode to form multilayered self-assemblies by layer-by-layer deposition based on electrostatic interaction. The (P2W18|RuDen) multilayer films have been investigated with UV−visible spectrometry, cyclic voltammetry, and TappingMode atomic force microscopy. They showed a bifunctional electrocatalytic capability, namely, iodate reduction and arsenite oxidation.
Opiate withdrawal increases ornithine decarboxylase activity which is otherwise unaltered in brains of dependent chicken fetuses

Abstract We have used the developing chicken to determine if ornithine decarboxylase (ODC) activity is altered in fetuses chronically exposed to the opiate N-desmethyl-l-α-acethylmethadol (NLAAM) or rendered abstinent by acute injection of naloxone (Nx). Exposure to NLAAM from day 3 of embryogenesis did not significantly change brain ODC activity in 15, 17 or 19-day-old fetuses. Acute treatment of 17-day-old fetuses with a motility suppressant dose of NLAAM did not differentially affect ODC activity in NLAAM-dependent fetuses, but an additional treatment with Nx, which precipitated withdrawal, resulted in a significant increase in ODC activity in this group. We conclude that withdrawal can alter fetal ODC activity which otherwise appears normal, even though fetuses have been chronically exposed to and dependent upon an opiate.
Novel peak assignments of in vivo (13)C MRS in human brain at 1.5 T.

(13)C MRS studies at natural abundance and after intravenous 1-(13)C glucose infusion were performed on a 1.5-T clinical scanner in four subjects. Localization to the occipital cortex was achieved by a surface coil. In natural abundance spectra glucose C(3beta,5beta), myo-inositol, glutamate C(1,2,5), glutamine C(1,2,5), N-acetyl-aspartate C(1-4,C=O), creatine CH(2), CH(3), and C(C=N), taurine C(2,3), bicarbonate HCO(-)(3) were identified. After glucose infusion (13)C enrichment of glucose C(1alpha,1beta), glutamate C(1-4), glutamine C(1-4), aspartate C(2,3), N-acetyl-aspartate C(2,3), lactate C(3), alanine C(3), and HCO(-)(3) were observed. The observation of (13)C enrichment of resonances resonating at >150 ppm is an extension of previously published studies and will provide a more precise determination of metabolic rates and substrate decarboxylation in human brain.
The effect of varying doses of d-amphetamine on activity levels of prepubertal mice.

Abstract The effect of varying doses of d -amphetamine on the activity level of C57BL/6J mice (known for their high activity level), DBA/1J, C3H/HeJ, and C 3 D 2 F 1 mice was investigated (all mice were 25 to 30 days old). Activity was measured by the use of an activity cage with a revolving drum. After determination of baseline activity level, the animals were assigned to the following set of i.p. injections: (1) normal saline, (2) d -amphetamine 0.2mg/kg, (3) d -amphetamine 0.5 mg/kg, (4) d -amphetamine 5mg/kg. The mean activity level of the C57BL/6J mice was significantly higher than that of the other strains. The mean activity level after 5 mg/kg was significantly lower than after other dosages in all strains. All strains responded similarly to d -amphetamine as is apparent from the parallel profiles for the dose-response curves. The response of the developing mice to d -amphetamine is at variance with the known response of mature mice.
Audio enriched links: web page previews for blind users

Audio Enriched Links provide previews of linked web pages to users with visual impairments. Before a user follows a hyperlink, the Audio Enriched Links software presents a spoken summary of the next page including its title, its relation to the current page, statistics about its content, and some highlights from its content. We believe that such a summary may be a useful surrogate for a full web page, and help users with visual impairments decide whether or not to spend time visiting a linked page. In this paper, we present some motivation for the Audio Enriched Links project. We describe the design and implementation of the current software prototype, and discuss the results of an initial evaluation involving four participants. We conclude with some implications of this work and directions for future research.
Functional polymers. XLVIII. Polymerization of ω‐alkenoate derivatives

Esters of ω-alkenoic acids have been homopolymerized with transition metal initiating systems. The key to the successful polymerization was the complexation of the monomer prior to its addition to the initiating system. Titanium trichloride, aluminum activated, was found to be best as the transition metal part of the initiator systems, with diethyl-, or better, diisobutylaluminum chloride as the reducing agents and n-hexane or toluene as the solvents. Best results for polymerizations were obtained with 2,6-dimethylphenyl esters of the functional α-olefin monomers; however, other phenyl esters also polymerized well. Attempts to polymerize methyl 10-undecenoate gave the corresponding polymer in only low yields. Polymers of the 2,6-dimethylphenyl esters, obtained in high molecular weight, were characterized. Polymers were also obtained from 2,6-dimethylphenyl 7-octenoate, but not from ω-alkenoates with less than three methylene units between the ester group and the terminal olefin group. Poly(2,6-dimethylphenyl 10-undecenoate) was hydrolyzed in an aqueous sodium hydroxide/1,4-dioxane solution to poly(sodium 10-undecenoate) that in turn was neutralized with acetic acid to poly(10-undecenoic acid).
THE IMPLEMENTATION OF MONETARY POLICY WITH SPECIAL ATTENTION TO THE AVAILABILITY OF CREDIT

THE cost-of-money doctrine, which emerged in the institutional complex of the London market for funds, came to dominate the theory of monetary policy after the monetary-equilibrium analysis of Wicksell cast the doctrine in a theoretical framework of general applicability. Further theoretical elucidation led to the view that the chief, if not sole, implement of monetary policy was the manipulation of the rate of interest to influence the investment decisions of entrepreneurs. Criticisms of the doctrine, especially after the economic collapse of the early 1930's, concluded that the ability of the monetary authorities to control the market rate of interest was limited and that investment decisions were not much affected by the cost of money. In recent years, there has been reason to question these conclusions. Emphasizing the "availability of credit" as an implement of monetary policy, the availability-of-money doctrine has taken issue with the view that the rate of interest is the only means by which lendable funds are rationed. Borrowers may find themselves in the "unsatisfied fringe" as a result of deficient organization of lending facilities, risk premiums exacted in other terms of the loan contract than interest charges, and the fact that at times lenders may consider themselves loaned-up. There may also be an "unsatisfied fringe" of lenders as the central bank may ration its funds by other means than price. Changes in the availability of money have significance for the expenditure plans of entrepreneurs and consumers and may influence not only the rate of spending with borrowed funds but the rate of spending with existing balances. The significance of changes in the supply of loanable funds has also received much emphasis in the recent revision of the theory of monetary policy. Such changes have sometimes been referred to as changes in the "availability of credit." However, to distinguish the effect of the non-price rationing mechanisms from the quantitative effect of monetary policy, the supply-of-funds doctrine has developed
THYROID HORMONE INDUCED SWELLING OF ISOLATED DOGFISH LIVER MITOCHONDRIA.

Abstract Calorigenically active iodothyronines accelerate swelling of isolated dogfish liver mitochondria. 3,5,3′-triiodothyroacetic acid, the most active compound tested, is effective at 2.5 × 10 −6 M concentration. Liver mitochondria of Mustelus canis appear less resistant to osmotic change than rat liver mitochondria and also differ in their release of protein on incubation and in their response to certain inhibitors. The relationship of mitochondrial swelling to calorigenic response has been discussed briefly.
Effect of spider orb-web and insect oscillations on prey interception

The collision model describes insect interception at spider orb-webs as a static process where prey capture is determined by the relationship between the size of the web's mesh and the size of potential prey. However, orb-webs are not static nets and prey capture reflects a dynamic interaction between spider and insect. One component of this interaction is web oscillation. We show that the natural oscillations of orb-webs greatly enhance web interception of small and slowly flying prey. We predict that the oscillatory behavior of webs are an important means of ecological differentiation between adult spiders of different species and sizes as well as between spiders of the same species but different age classes.