cssi/SciSciGPT-SciSciNet huggingface dataset:
A Complex Case of Sarcoidosis Fever

Febrile episodes in a male patient with coronary artery disease and arteriovenous malformation of the spinal cord had been attributed to urinary-tract infections and pulmonary atelectasis. The autopsy findings, however, indicated that the fever may have been related to sarcoidosis which had not been detected pre mortem.
Nucleic acid vaccination of Brucella abortus ribosomal L7/L12 gene elicits immune response.

Nucleic acid vaccines provide an exciting approach for antigen presentation to the immune system. As a test of this new methodology, the immune response to the in vivo-expressed Brucella abortus ribosomal L712 gene in the muscle cells of mice was examined. To accomplish this goal the eukaryotic expression systems pcDNA3 and p6 were used. Single intramuscular injection of the L7L12 gene driven by the human cytomegalovirus (CMV) promoter (pcDNA3) or bovine MHC I promoter (p6) resulted in intracellular expression of the B. abortus L7L12 immunodominant protein encoded by this gene. This application facilitated directed antigen presentation to the immune system and established specific antibody and T-cell responses compared with vector only (pcDNA3) negative controls and B. abortus S19 injected positive controls. Although pcDNA3-encoded L7L12 gene-inoculated mice possessed significant protection, p6-L7L12 did not engender significant protection against B. abortus S2308 infection compared to positive control mice. These data suggest a promising antigen-specific response, and L7L12 nucleic acid vaccination may be an initial step in the development of genetically engineered candidate vaccines against brucellosis. This study for the first time focuses on DNA immunization of a gene from B. abortus.
Rapid increase in viability due to new beneficial mutations in Drosophila melanogaster

It is usually assumed that new beneficial mutations are extremely rare. Yet, few experiments have been performed in multicellular organisms that measure the effect of new beneficial mutations on viability and other measures of fitness. In most experiments, it is difficult to clearly distinguish whether adaptations have occurred due to selection on new beneficial mutations or on preexisting genetic variation. Using a modification of a Dobzhansky and Spassky (Evolution 1:191-216, 1947) assay to study change in viability over generations, we have observed an increase in viability in lines homozygous for the second and third chromosomes of Drosophila melanogaster in 6-26 generations due to the occurrence of new beneficial mutations in population sizes of 20, 100 and 1,000. The lines with the lowest initial viability responded the fastest to new beneficial mutations. These results show that new beneficial mutations, along with selection, can quickly increase viability and fitness even in small populations. Hence, new advantageous mutations may play an important role in adaptive evolution in higher organisms.
Inhalation Challenge with Sulfidopeptide Leukotrienes in Human Subjects

What is the meaning of these findings to the practicing chest physician? First, leukotrienes are potent airway constrictors; they are capable of reproducing the type of airway constriction observed in asthma. The role of leukotrienes in this regard has yet to be established, but experiments to test the importance of these agents in this setting are likely to be performed soon. Specifically, several leukotriene receptor antagonists or synthesis inhibitors have been identified and may provide the tools needed to test this crucial hypothesis. Second, the leukotrienes are unique bronchoactive agents in that the degree of hyperresponsiveness between normal and asthmatic subjects varies markedly with the bronchoconstrictor index used to assess response. When one compares normal subjects to asthmatic subjects, there is substantial overlap in leukotriene sensitivity among groups when V30-P is used as the bronchoconstrictor index. However, when the FEV1 is used as the bronchoconstrictor index, there is little overlap in sensitivity between normal and asthmatic subjects, and the separation between the two groups is even more clearly made than it is with histamine or methacholine challenge. Thus, LTD4 inhalation challenge may replace the histamine and methacholine challenges in the diagnosis of cryptic shortness of breath. Third, the differential sensitivity of various bronchoconstrictor indices in both normal and asthmatic subjects when leukotrienes are used may provide clues as to the locus of airway hyperresponsiveness in asthma. Thus, leukotrienes hold the promise of new ways to treat and diagnose asthma, as well as providing new insights into the pathobiology of the disease itself.
Integrins as novel drug discovery targets: potential therapeutic and diagnostic implications

The role of integrin and extracellular matrix proteins in various pathological processes (including angiogenesis, thrombosis, apoptosis, cell migration and proliferation), leading to both acute and chronic disease states (such as ocular diseases, metastasis, unstable angina, myocardial infarction, stroke, osteoporosis, a wide range of inflammatory diseases, vascular remodelling, neurodegenerative disorders), has been recently documented. A key success in this field is evident from the potential role of the platelet GPIIb/IIIa integrin in the prevention, treatment and diagnosis of various thromboembolic disorders. Additionally, progress in the development of leukocyte α4β1 antagonists for various inflammatory indications and αv integrin antagonists for angiogenesis and vascular-related disorders has occurred. The rationale for the development of various therapeutic and diagnostic candidates based on the key role of integrin in various diseases will be reviewed.
Pathology of common skin tumors.

The clinical and histologic appearance of basal cell epithelioma, squamous cell carcinoma, solar keratosis, leukoplakia, keratoacanthoma, and Bowen's disease is discussed. The association of Bowen's disease with visceral cancer is also mentioned. Several questions and answers are included at the end of the article.
Note: Accurate determination of thickness of multiple layers of thin film deposited on a piezoelectric quartz crystal

Modern day piezoelectric quartz crystal microbalances for thin film deposition control are based on Z-match equation, which is mathematically valid for deposition of a single material on a given quartz crystal. When multiple layers are deposited, thickness and deposition rate errors accumulate due to mismatch of acoustic impedance of different materials. Here we present a novel method, based on the acoustic transfer matrix formalism, for accurate determination of thickness of an arbitrary number of layers of dissimilar materials deposited on a quartz crystal. Laboratory data show excellent accuracy of the method compared to conventional Z-match equation.
Pulsed-laser deposition of particulate-free TiC coatings for tribological applications

Hybrid bearings comprising ceramic or ceramic-coated steel balls and steel raceways can provide good fatigue life and resistance to wear. One of the coating materials that has received serious consideration in hybrid systems is titanium carbide (TiC). At present, the commercially available process for the deposition of TiC involves the heating of steel substrates to fairly high temperatures (>900 °C). The high-temperature process involves considerable costs and complexities that are associated with the post-deposition heat treatment and repolishing of the coated steels for bearing applications. Pulsed-laser deposition (PLD) is ideally suited to deposit TiC coatings on bearing steels at room temperature. However, it is well known that codeposition of particulates has been one of the most challenging problems of PLD. This is especially of concern when dealing with hard coatings for tribological applications. Here we describe a novel and extremely simple method of depositing high-quality, particulate-free TiC coatings on bearing steel surfaces that uses PLD. The method relies on a new non-line-of-sight deposition that uses a permanent magnet and prevents particulates from arriving at the substrate. The surface roughness of TiC films deposited on steels by way of this technique has an extremely low root mean square value of 1.6 nm. The TiC films have been extensively characterized for their morphology, chemical composition, and mechanical properties with scanning electron and atomic force microscopy, X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and nanoindentation. Time-resolved emission has been used for the in situ characterization of the laser-ablated TiC plume and has resulted in the identification of various plume species as a function of laser parameters. The spectroscopic results are correlated to film growth and to our modified PLD method.
A Comparison of Physical Therapy in Two School Based Treatment Contexts

Children with physcial disabilities enrolled in special education frequently receive physical therapy as part of their Individualized Educational Plans (IEP). This study compared the effects of providing physical therapy in two different settings: an isolated therapy room or a natural (where the skills would naturally occur) educational setting. Three children were evaluated on a motor skill task using an alternating treatment that contrasted their performance between the two settings. The skills were evaluated for both speed of completion as well as two quality of performance measures. The results suggested that the natural educational setting resulted in a superior performance of skills for all three children.
Widespread Gene Delivery and Structure-Specific Patterns of Expression in the Brain after Intraventricular Injections of Neonatal Mice with an Adeno-Associated Virus Vector

Developing a system for widespread somatic gene transfer in the central nervous system (CNS) would be beneficial for understanding the global influence of exogenous genes on animal models. We injected an adeno-associated virus serotype 2 (AAV2) vector into the cerebral lateral ventricles at birth and mapped its distribution and transduction pattern from a promoter capable of expression in multiple targets. The injections resulted in structure-specific patterns of expression that were maintained for at least 1 year in most regions, with efficient targeting of some of the major principal neuron layers. The patterns of transduction were explained by circulation of the viral vector in the subarachnoid space via CSF flow, followed by transduction of underlying structures, rather than by progenitor cell infection and subsequent migration. This study demonstrates that gene transfer throughout the CNS can be achieved without germ line transmission and establishes an experimental strategy for introducing genes to somatic cells in a highly predictable manner.
Approaches to Tyrosine-Linked Peptidomimetic Prodrugs of (S)-HPMP-Based Acyclic Nucleoside Phosphonates

Synthetic approaches to a new class of tyrosine-linked prodrugs of two 3-hydroxy-2-(phosphonomethoxypropyl) (HPMP) nucleotide analogues [(S)-HPMPC and (S)-HPMPA] are outlined.
The Concept of Lymph Node Density—Is it Ready for Clinical Practice?

Purpose: The concept of lymph node density (ratio of positive-to-total number of nodes examined) is reviewed as a prognostic factor for recurrence-free survival after cystectomy in patients with invasive bladder cancer.Materials and Methods: The literature was queried for all articles that directly or indirectly address lymph node density (nodal ratios) and survival of bladder cancer.Results: Five studies on a total of 979 patients were found. In 4 studies lymph node density was a significant predictive factor for survival when adjusted for patient, tumor and treatment covariates.Conclusions: Considerable data support the use of lymph node density in bladder cancer prognosis. A methodological evaluation of the prognostic importance of nodal ratios in large multicenter data sets and validation in a prospective clinical trial are merited before lymph node density is accepted into routine clinical practice.
“Neither the same Nation Nor Different Nations”: Constitutional Conventions in the United States and Australia

Debates in constitutional conventions in the United States in 1787 and Australia in 1897 reveal similarities and differences that illuminate the process by which nations became increasingly meaningful forms of social organization. Although the tone of these debates tended to be technical and pragmatic, focusing on specific concerns about the machinery of “good government,” convention delegates showed in their assumptions, their omissions, and in the claims and comparisons they repeated, what they were coming to perceive as commonalities. Claims about what identified the new nations were part of the repertoire of debate used by delegates as they addressed their tasks. So the conventions distilled ideas available to political elites about what was taken to be distinctive about and shared by prospective citizens.
An open baseband processing architecture for future mobile terminal design

This article introduces an open wireless architecture (OWA) mobile terminal design, focusing on the open baseband processing platform, to support different existing and future wireless communication standards through multi-dimensional open baseband processing modules with open interface parameters and baseband management systems. The article describes a multilayer, open architecture platform to maximize system flexibility and minimize terminal power consumption, so as to provide an integrated and converged next-generation wireless and mobile communication terminal system. The OWA platform is fully compatible with the computer architecture, with interface-based rather than transmission-specific system architecture, for complete openness and simplicity.
A double layer microstrip spatial amplifier with increased active device density

A new quasi-optical amplifier consisting of four HEMTs coupled to a single receiving and a single transmitting microstrip patch antenna is presented. This circuit can be used as a unit cell for the construction of a power combining amplifier array at millimeter-wave frequencies. The advantage of this circuit is its high active device density which is desirable in the construction of monolithic integrated circuits. The amplifier was constructed on double layer back to back microstrip circuits with a shared ground plane which provides an effective isolation between the receiving antenna and the transmitting antenna. The coupling between the two stages is accomplished through microstrip to slot transitions, which facilitates monolithic fabrication of such amplifiers. The measured gain at 10.1 GHz is 10 dB.
On the stability of the Discrete Generalized Multigroup method

Abstract This paper investigates the stability of the recondensation procedure of the Discrete Generalized Multigroup method and proposes alternatives to improve stability of the original formulation. Instabilities are shown to happen when employing a simple Picard fixed point iteration and an ill-informed group mapping scheme. This work presents a mapping procedure that improves stability of the original method for fine group calculations. Additionally, a relaxation scheme, Krasnoselskij iteration, is introduced to the fixed point iteration to further improve the stability characteristics and remove the need for fine group flux updates. Both improvements are applied on heterogeneous problems using the SHEM361 and the NG2042 group structures. The results indicate improved stability from a well-informed group mapping and demonstrate the possibility of eliminating the need for fine group flux updates.
A model for the characterization of the spatial properties in vestibular neurons

Quantitative study of the static and dynamic response properties of some otolith-sensitive neurons has been difficult in the past partly because their responses to different linear acceleration vectors exhibited no "null" plane and a dependence of phase on stimulus orientation. The theoretical formulation of the response ellipse provides a quantitative way to estimate the spatio-temporal properties of such neurons. Its semi-major axis gives the direction of the polarization vector (i.e., direction of maximal sensitivity) and it estimates the neuronal response for stimulation along that direction. In addition, the semi-minor axis of the ellipse provides an estimate of the neuron's maximal sensitivity in the "null" plane. In this paper, extracellular recordings from otolith-sensitive vestibular nuclei neurons in decerebrate rats were used to demonstrate the practical application of the method. The experimentally observed gain and phase dependence on the orientation angle of the acceleration vector in a head-horizontal plane was described and satisfactorily fit by the response ellipse model. In addition, the model satisfactorily fits neuronal responses in three-dimensions and unequivocally demonstrates that the response ellipse formulation is the general approach to describe quantitatively the spatial properties of vestibular neurons.
Theory of Reactive Adsorption on Si(100)

Density functional calculations on cluster models of Si(100)-2xl have been used to predict reaction mechanisms and energetics for several reactive adsorption processes. Dissociative adsorption of H2, H20, BH3, and SiH4 will be described and compared to available experimental data. Based on these examples, a qualitative theory of mechanisms for dissociative adsorption of hydrides on silicon surfaces will be proposed. These reactions can largely be understood in terms of the electron density distributions in the molecule and surface dimer. On a buckled dimer, there are both electron-rich and electron-deficient sites, which have different chemical interactions with adsorbates. The role of this difference is illustrated in a novel surface Diels-Alder reaction, for which symmetric addition to an unbuckled surface dimer is allowed by orbital symmetry. This reaction creates new reactive surface sites that may be useful for subsequent chemical surface modification.
Duodenogastric Reflux-induced (Alkaline) Esophagitis.

Duodenogastric reflux is the retrograde flow of duodenal contents into the stomach that then mix with acid and pepsin. These agents can reflux into the esophagus (ie, duodenogastroesophageal reflux [DGER]) and cause gastroesophageal reflux disease (GERD) and its complications, including stricture, Barrett’s esophagus, and adenocarcinoma of the esophagus. Medical and surgical treatments of DGER can be difficult. Best medical treatment is proton-pump inhibitors, which decrease DGER by inhibiting both gastric acidity and volume, making less gastric contents available to reflux into the esophagus. The addition of the gamma-aminobutyric (GABAB) recepto agonist baclofen may further reduce DGER in patients not responding to proton-pump inhibitors. Bile acid-binding agents (aluminum-containing antacids, cholestyramine, sucralfate, urosodeoxycholic acid) have physiologic rationale, but their efficacy is unproven. Prokinetic agents can reduce DGER and its upper gastrointestinal symptoms by promoting increased gastric emptying. In patients with medically refractory symptoms, a Roux-en-Y diversion or duodenal switch operation may be helpful.
Characterization and heterogeneity of coarse particles across an urban area

Abstract Coarse particles exposures are expected to be highly heterogeneous in an urban area. However, little data are available to explore the extent of heterogeneity of coarse particles, especially on a local scale. An extensive sampling program for the coarse particles was conducted using University of North Carolina (UNC) passive aerosol samplers. The samplers were deployed for 4–5 week periods during four seasons, fall, winter, spring, and summer at 25 different sites across Syracuse, a small city located in central New York. The substrates from the UNC passive samplers were analyzed with computer-controlled scanning electron microscopy (CCSEM) providing size, shape, and elemental composition in the form of fluoresced X-ray spectra. Adaptive resonance theory (ART-2a) based neural network algorithm was applied with processed X-ray data to identify homogenous particles classes of 25,437 coarse particles from all four seasons. Thirty-four particle classes were identified with similar chemical characteristics. The mass fractions of particles in each identified class were then used to assess the homogeneity of composition and concentration across the measurement domain for each season. Road/soil dust, carbonaceous dust, biological materials, and deicing road salt were identified as the major sources of the urban coarse particles. Spatial and seasonal variations in both composition and concentration were observed and a noticeable heterogeneity between adjacent sites is indicated by the coefficient of divergence and correlation coefficient analysis.
On Jupiter's whistler emission

A theory explaining Jupiter's banded whistler emission, in particular low-frequency hiss and chorus, is proposed. It is shown that superthermal electrons described by a kappa distribution function cause whistler instability below one-third of the electron gyrofrequency, whereas a two temperature Maxwellian leads to a band of unstable growing modes just below one-half of the electron gyrofrequency. A superposition of both yields almost exactly the structure of whistler mode hiss and chorus detected by the Voyager 1 and 2 plasma wave instrument.
Induction and glucose repression of xylanase from a color variant strain ofAureobasidum pullulans

Xylose, xylobiose and arabinose were identified as natural and direct inducers of xylanase from a color variant strain ofAureobasidium pullulans. Arabinose, in contrast to xylose, xylobiose and xylan, induced only the major isozyme of xylanase. Xylanase induction was subject to glucose repression.
Uniform versus peak-load pricing of a bottleneck with elastic demand

Abstract This paper considers commuting to work across a bottleneck such as a bridge or tunnel, with elastic demand. With no toll, there is wasteful queueing. The optimal peak-load toll eliminates queueing and leaves total traffic unchanged. The second-best uniform toll cannot eliminate queueing, but reduces total traffic. The second-best uniform toll may be larger or smaller than the maximum value of the optimal peak-load toll.
Update in ARDS management: recent randomized controlled trials that changed our practice.

In the last 7 years, 14 randomized controlled trials in patients with acute respiratory distress syndrome (ARDS) have shown that: • Mechanical ventilation with a tidal volume of 6 mL/kg of predicted body weight is better than mechanical ventilation with a tidal volume of 12 mL/kg of predicted body weight. • Prone positioning improves oxygenation but poses safety concerns. • A high level of positive end-expiratory pressure does not improve survival. • High-frequency oscillatory ventilation is in theory the ideal "lung-protective" method, but its benefits have not been proven. • No drug therapy has been shown to improve survival in patients with ARDS. • Exogenous surfactant may improve oxygenation but has no significant effect on the death rate or length of use of mechanical ventilation. • Low-dose inhaled nitric oxide has no substantial impact on the duration of ventilatory support or on the death rate. • Partial liquid ventilation may be beneficial in young patients with acute lung injury or ARDS, although further study is needed to confirm this.
New Optical Difference Approaches for Sub-Surface Imaging of Tissues

Subsurface imaging approaches are described based on the wavelength and polarization dependence of the backscattered light from different tissue components under polarized illumination and the optical characteristics of a luminous object relative to the absorption and emission characteristics of the host tissue.
Phosphorylation and localization of protein-zero related (PZR) in cultured endothelial cells.

Protein-zero related (PZR) is an immunoglobulin V (IgV)-type immunoreceptor with two immunoreceptor tyrosine-based inhibitory motifs (ITIMs). PZR interacts with Src homology 2 domain–containing tyrosine phosphatase (SHP-2) via its tyrosine-phosphorylated ITIMs, for which c-Src is a putative kinase. Towards elucidating PZR function in endothelial cells (ECs), the authors cloned PZR from bovine aortic endothelial cells (BAECs) and characterized it. Mature bovine PZR had 94.8% and 92.7% sequence identity with canine and human proteins, respectively, and the two ITIM sequences were conserved among higher vertebrates. PZR was expressed in many cell types and was localized to cell contacts and intracellular granules in BAECs and mesothelioma (REN) cells. Coimmunoprecipitation revealed that PZR, Grb-2–associated binder-1 (Gab1), and platelet endothelial cell adhesion molecule-1 (PECAM-1) were three major SHP-2–binding proteins in BAECs. H2O2 enhanced PZR tyrosine phosphorylation and PZR/SHP-2 interaction in ECs ...
Differential appearance of opiate receptor subtypes in neonatal rat brain

Abstract Radioreceptor binding techniques were utilized to examine the developmental appearance of μ, δ and k opioid receptors in rat brain. Significant differences were found in the relative proportions of the three receptor subtypes in neonatal and adult CNS. Whereas in adult brain μ and δ receptors were predominant, in 6 day old pups the receptors were primarily of the μ and k subtype. These results indicate that the three opioid receptors exhibit dissimilar developmental patterns.
The surface and materials science of tin oxide

Abstract The study of tin oxide is motivated by its applications as a solid state gas sensor material, oxidation catalyst, and transparent conductor. This review describes the physical and chemical properties that make tin oxide a suitable material for these purposes. The emphasis is on surface science studies of single crystal surfaces, but selected studies on powder and polycrystalline films are also incorporated in order to provide connecting points between surface science studies with the broader field of materials science of tin oxide. The key for understanding many aspects of SnO 2 surface properties is the dual valency of Sn. The dual valency facilitates a reversible transformation of the surface composition from stoichiometric surfaces with Sn 4+ surface cations into a reduced surface with Sn 2+ surface cations depending on the oxygen chemical potential of the system. Reduction of the surface modifies the surface electronic structure by formation of Sn 5s derived surface states that lie deep within the band gap and also cause a lowering of the work function. The gas sensing mechanism appears, however, only to be indirectly influenced by the surface composition of SnO 2 . Critical for triggering a gas response are not the lattice oxygen concentration but chemisorbed (or ionosorbed) oxygen and other molecules with a net electric charge. Band bending induced by charged molecules cause the increase or decrease in surface conductivity responsible for the gas response signal. In most applications tin oxide is modified by additives to either increase the charge carrier concentration by donor atoms, or to increase the gas sensitivity or the catalytic activity by metal additives. Some of the basic concepts by which additives modify the gas sensing and catalytic properties of SnO 2 are discussed and the few surface science studies of doped SnO 2 are reviewed. Epitaxial SnO 2 films may facilitate the surface science studies of doped films in the future. To this end film growth on titania, alumina, and Pt(1 1 1) is reviewed. Thin films on alumina also make promising test systems for probing gas sensing behavior. Molecular adsorption and reaction studies on SnO 2 surfaces have been hampered by the challenges of preparing well-characterized surfaces. Nevertheless some experimental and theoretical studies have been performed and are reviewed. Of particular interest in these studies was the influence of the surface composition on its chemical properties. Finally, the variety of recently synthesized tin oxide nanoscopic materials is summarized.
Late Wisconsinan drift stratigraphy of the Saginaw Ice Lobe in south-central Michigan

Clay-mineral analyses have been used to define two Late Wisconsinan till sheets of the Saginaw Lobe in southwestern Michigan. Bedford till can be traced along the ground surface from the Lansing Moraine southward to exposures within the Kalamazoo Moraine, and Fulton till can be traced in the subsurface southward from the Lansing Moraine, through a series of bore-holes, to exposures within the Tekonsha Moraine. Both tills are sometimes separated by a layer of sand and gravel. The presence of sand and gravel between the Bedford and Fulton tills further suggests that a significant retreat (>60 km) of the Saginaw Lobe occurred between the formation of the Tekonsha and Kalamazoo Moraines. Morpho-stratigraphic correlations between moraines of the Saginaw and Huron-Erie Lobes suggest that the interval between the deposition of the Bedford and Fulton tills is probably time equivalent to the Erie Interstade. Correlations between moraines of the Lake Michigan and Saginaw Lobes in southwestern Michigan also suggest that the Erie Interstade occurred in the Lake Michigan Lobe between the deposition of Ganges and Saugatuck tills.
Does Dividend Policy Relate to Cross‐Sectional Variation in Information Asymmetry? Evidence from Returns to Insider Trades

We examine the relation between dividends and information asymmetry by using insider returns as a proxy for information asymmetry. We find that dividends are negatively related to returns to insider trades across firms. Firms that pay consistently high dividends have lower insider returns than do firms that pay consistently low dividends. These results do not support traditional dividend signaling models. Rather, they are consistent with the proposition that firms with the highest dividends have the lowest levels of information asymmetry.
Pediatric training and job market trends: results from the American Academy of Pediatrics third-year resident survey, 1997-2002.

Objectives. To examine trends in pediatric residents’ training and job search experiences from 1997–2002. Methods. Annual national random samples of 500 graduating pediatric residents were surveyed, and responses were compared across survey years to identify trends. The overall response rate was 71%. Results. From 1997–2002, there were more female residents and US underrepresented minorities and fewer international medical graduates. Each successive group of residents rated higher their preparation for fellowship training, for child advocacy, and for assessing community needs. These increases paralleled an increase in resident exposure to community sites as part of their residency education. Educational debt (in 2002 dollars) for residents increased substantially across survey years from an average of $64 070 in 1997 to $87 539 in 2002. Meanwhile, starting salaries (in 2002 dollars) for residents entering general pediatrics actually decreased. Interest in general pediatrics among residents decreased, whereas interest in subspecialty practice increased during this time period. Fewer residents with general pediatrics as a career goal had a job when surveyed, and fewer obtained their first-choice positions across years. Conclusions. Experiences of graduating residents over the past 6 years provide insights into changes in pediatric residency education and the pediatric workforce. Efforts by pediatric educators and academic leaders to increase community experiences and child advocacy and to encourage greater interest in pediatric subspecialty careers seem to be succeeding. Unfortunately, demand for general pediatricians is weakening, and residents are experiencing increasing debt burdens.
Measurement of Aero-Optic Distortion in Transonic and Hypersonic, Turbulent Boundary Layers with Gas Injection

Here, we summarize the results of our investigation of means for controlling high-speed flows using helium injection, with particular emphasis on the wavefront distortion of light transmitted through the boundary layer. Quantitative estimates of wavefront distortion were obtained, with and without helium injection, and new diagnostic techniques were developed, including a MHz rate Hartmann wavefront sensor. In particular, we demonstrated the ability to capture real-time wavefront data in two dimensions using an ultra-fast Shack-Hartmann sensor in hypersonic and transonic turbulent boundary layers. These measurements have high temporal resolution (2 μ μ μ μs), while providing full dimensional information on the planar field. Such measurements are vital for making accurate and complete estimates of aero-optic distortion due to boundary layer turbulence in air-borne laser applications, and to assess quantitatively the effectiveness of control methods. I. Introduction he index-of-refraction variations that degrade the performance of on-board optical systems for tracking and imaging targets are primarily due to the presence of turbulent free shear layers and turbulent boundary layers, and density discontinuities across shock waves. In directed energy and communication link applications, density fluctuations in the boundary layer cause image break-up and rapidly varying motions, reducing both image and target resolution, and diminishing the power and total energy on target. For tracking applications another important issue is the variation of “bore-sight” error with missile angle-of-attack. Bore-sight error is the difference between the apparent location of the target and its actual location relative to the missile reference frame. As the missile angle-of-attack varies, the apparent location of the target changes because the light rays are bent as they pass through shock waves and through the boundary layer before entering the window. As the name suggests, aero-optics is the study of the interaction between light and air. More specifically, it is the study and measurement of the distortion of light due to propagation through an index of refraction field which is thin with respect to the imaging (or projecting) aperture. In contrast, atmospheric propagation involves distortion distances much greater than the aperture, and has been studied at some length in the context of ground based astronomical telescopes. For airborne laser systems, this is called the far field problem. Astronomers are now able to measure and compensate for these distortions in real time, effectively ‘de-twinkling’ the stars. Aero-optics is concerned with the near field problem, where the distortions are caused by the vehicle flow field itself, and is by comparison at a nascent stage of development.
A 0.8 ps DNL Time-to-Digital Converter With 250 MHz Event Rate in 65 nm CMOS for Time-Mode-Based $\Sigma \Delta$ Modulator

A time-to-digital converter (TDC) is proposed to replace the multi-bit quantizer and the multi-bit feedback DAC of traditional voltage-mode ΣΔ modulator. Since time-mode systems process analog signals encoded in the time dimension rather than the voltage dimension, the proposed time-mode TDC makes the multi-bit ΣΔ ADC digital friendly and more suitable for nanometric technologies. A pulse-width-modulator (PWM) converts the sampled-and-held voltage-sample to a digital pulse whose width is proportional to the voltage level of the sample. Then, the TDC generates a digital code that corresponds to the pulse width. Simultaneously, the TDC provides a time-quantized feedback pulse for the ΣΔ modulator, emulating the voltage-DAC in a conventional ΣΔ ADC. Linearity, jitter and data-dependent-delay effects on the performance of the proposed architecture are analyzed. A chip prototype is fabricated in TI 65 nm digital CMOS process. THD of 67 dB is achieved which corresponds to a TDC's DNL of less than 0.8 ps without calibration. Measurements show that the ΣΔ-modulator achieves a dynamic range of 68 dB and the TDC consumes 5.66 mW at 250 MHz event rate while occupying 0.006 mm2.
Validation of flow cytometric competitive binding protocols and characterization of fluorescently labeled ligands.

Background: Fluorescently labeled ligands and flow cytometric methods allow quantification of receptor-ligand binding. Such methods require calibration of the fluorescence of bound ligands. Moreover, binding of unlabeled ligands can be calculated based on their abilities to compete with a labeled ligand. In this study, calibration parameters were determined for six fluorescently labeled N-formyl peptides that bind to receptors on neutrophils. Two of these ligands were then used to develop and validate competitive binding protocols for determining binding constants of unlabeled ligands. Methods: Spectrofluorometric and flow cytometric methods for converting relative flow cytometric intensities to number of bound ligand/cell were extended to include peptides labeled with fluorescein, Bodipy, and tetramethylrhodamine. The validity of flow cytometric competitive binding protocols was tested using two ligands with different fluorescent properties that allowed determination of rate constants both directly and competitively for one ligand, CHO-NLFNYK-tetramethylrhodamine. Results: Calibration parameters were determined for six fluorescently-labeled N-formyl peptides. Equilibrium dissociation constants for these ligands varied over two orders of magnitude and depended upon the peptide sequence and the molecular structure of the fluorescent tag. Kinetic rate constants for CHO-NLFNYK-tetramethylrhodamine determined directly or in competition with CHONLFNYK-fluorescein were statistically identical. Conclusions: Combination of spectrofluorometric and flow cytometric methods allows convenient calculation of calibration parameters for a series of fluorescent ligands that bind to the same receptor site. Competitive binding protocols have been independently validated. Cytometry 45:102‐114, 2001. © 2001 Wiley-Liss, Inc. Key terms: neutrophils; fluorescence calibration; binding kinetics; G-protein coupled receptor; N-formyl peptide receptor; flow cytometry
NONLINEAR EVOLUTION EQUATIONS AND NONLINEAR ERGODIC THEOREMS

Publisher Summary This chapter discusses nonlinear evolution equations and nonlinear ergodic theorems. It discusses certain aspects of the asymptotic behavior of generalized solutions of nonlinear evolution equations and of nonlinear nonexpansive semigroups in Banach spaces. The chapter discusses some results that can be used to derive iterative procedures for the construction of zeros of accretive sets. The first ergodic theorems for nonlinear nonexpansive mappings and semigroups in Hilbert space were established by Baillon and Brgzis. Bre'zis and Browder also simplified the original arguments in the discrete case and replaced the Ceslro method by more general summability methods.
Rage in Conjunction with the Machine

This report presents the design and construction of Rage in Conjunction with the Machine, a simple but novel pairing of musical interface and sound sculpture. The authors discuss the design and creation of this instrument, focusing on the unique aspects of it, including the use of physical systems, large gestural input, scale, and the electronic coupling of a physical input to a physical output.
Comment on 'the quality of government': why do some governments have better institutions than others?

The questions asked by La Porta, Lopez-de-Silanes, Shleifer, and Vishny are very important and inherently interesting. In general terms, if some (government) institutions are better in the sense that they produce better economic returns for the population, why would they not be generally adopted? The authors argue that there are particular political, cultural, and economic reasons, and they argue that these reasons are both conceptually and empirically distinct. Their measures of political and cultural variables have deep historical roots, suggesting major long-run differences in how a whole social system operates. Indeed, their model is at the level of Weber's (1958) Protestant ethic: Very general political and cultural attributes of a country, certainly not obviously related to any aspects of a country's output, impact governmental performance. The test they construct is a cross section of a large number of countries. While the argument is causal, the test is not. Though the characteristics they select are historically prior to their measures of particular aspects of government, neither the historic development of individual governments nor the causal mechanisms through which particular governmental structures and institutions were created are theorized or modeled. The inefficiency of socialist political systems are well documented, but the degrees of efficiency associated with other kinds of legal systems are not and it is not clear what results should be expected. To the degree that French legal origin is correlated with its former African colonies (e.g., Algeria), the Middle East, and southern Europe and related colonial influence within South America, the correlation with low government performance is not entirely surprising. Religious background and ethnolinguistic fractionalization are even less clear; countries differ in the degree to which these factors are allowed to enter into the governmental arena, and indeed the relevant question about ethnolinguistic fractionalization might well be under what conditions does it persist or assimilation take place? Theory and measures developed in some of the relevant literature they cite in the article might help to bridge the causal gap between governmental institutions and the very general concepts of legal system, religion, and ethnolinguistic differentiation that they rely upon. Recognizing the difficulty of putting these
Nutrient-dependent structural changes in S. aureus peptidoglycan revealed by solid-state NMR spectroscopy.

The bacterial cell wall is essential to cell survival and is a major target of antibiotics. The main component of the bacterial cell wall is peptidoglycan, a cage-like macromolecule that preserves ...
Sub-Lethal Gamma Radiation Effects on Prepupae, Pupae, and Adults of Angoumois Grain Moth

Effects of gamma radiation from cobalt-60 on prepupae, pupae, and adults of Sitotroga cerealella (Olivier) were determined. Pupal sensitivity depended on age at treatment; the older the pupae, the less susceptible. Irradiation of perpupae and 1-day-old pupae resulted in reduced numbers, delayed and incomplete adult emergence, and in structural deformities including twisted wings and fusion of tarsal and antennal segments. No dose tested on late pupae significantly affected adult emergence. Larvae hatched from the eggs of irradiated 1-day-old adults, but the number of F1 moths was less than in the controls. Females, irradiated at 10 kr as prepupae and mated with normal virgin males or vice versa, either did not oviposit or laid infertile eggs. Irradiation of early pupae at 20 kr may cause complete sterility of both sexes. Following irradiation of late pupae, no dose from 5 to 25 kr prevented hatching of eggs in crosses where treated males were mated to untreated females or vice versa. When males and females, irradiated as 1-day-old moths, were mated, egg deposition and hatchability were markedly reduced. The males remained fertile at all doses.
Fundamental measurement of the difficulty of test items

Abstract Two different procedures were used to measure the difficulties of Scholastic Aptitude Test items: a new distribution-free procedure that uses periodic functions and LOGIST, a well-developed optimization procedure that fits a logistic model. Despite the fact that the two procedures used different data in very different ways, they obtained virtually the same numbers. The new method exemplifies “fundamental” psychological measurement in as much as it is based on counting and ordinal properties of data only.
High order asymptotic preserving nodal discontinuous Galerkin IMEX schemes for the BGK equation

In this paper, we develop high-order asymptotic preserving (AP) schemes for the BGK equation in a hyperbolic scaling, which leads to the macroscopic models such as the Euler and compressible Navier-Stokes equations in the asymptotic limit. Our approaches are based on the so-called micro-macro formulation of the kinetic equation which involves a natural decomposition of the problem to the equilibrium and the non-equilibrium parts. The proposed methods are formulated for the BGK equation with constant or spatially variant Knudsen number. The new ingredients for the proposed methods to achieve high order accuracy are the following: we introduce discontinuous Galerkin (DG) discretization of arbitrary order of accuracy with nodal Lagrangian basis functions in space; we employ a high order globally stiffly accurate implicit-explicit (IMEX) Runge-Kutta (RK) scheme as time discretization. Two versions of the schemes are proposed: Scheme I is a direct formulation based on the micro-macro decomposition of the BGK equation, while Scheme II, motivated by the asymptotic analysis for the continuous problem, utilizes certain properties of the projection operator. Compared with Scheme I, Scheme II not only has better computational efficiency (the computational cost is reduced by half roughly), but also allows the establishment of a formal asymptotic analysis. Specifically, it is demonstrated that when 0 < e ? 1 , Scheme II, up to O ( e 2 ) , becomes a local DG discretization with an explicit RK method for the macroscopic compressible Navier-Stokes equations, a method in a similar spirit to the ones in Bassi and Rebay (1997) 3, Cockburn and Shu (1998) 16. Numerical results are presented for a wide range of Knudsen number to illustrate the effectiveness and high order accuracy of the methods.
Pre- and post-planned evaluation: Which is preferable?

This paper compares the advantages and disadvantages of the "pre-planned" and "postplanned" approaches to evaluating program effectiveness. These evaluative approaches are compared along a number of dimensions which include: (a) Reliability of data and the cost of collecting it; (b) Internal validity; (c) External validity; (d) Evaluation obtrusiveness and threat; and (e) Program goal displacement and program direction. A model designed to help program managers decide when and under what conditions either of these two evaluative approaches should be employed is presented. One major theme throughout this discussion is that despite the growing interest in and use of pre-planned evaluation, the post-planned method has many advantages which often go unnoticed. This paper will help program administrators, planners and evaluators in selecting and implementing these two methods in light of their respective strengths and limitations.
Conditional Gene Genealogies under Strong Purifying Selection

The ancestral selection graph, conditioned on the allelic types in the sample, is used to obtain a limiting gene genealogical process under strong selection. In an equilibrium, two-allele system with strong selection, neutral gene genealogies are predicted for random samples and for samples containing at most one unfavorable allele. Samples containing more than one unfavorable allele have gene genealogies that differ greatly from neutral predictions. However, they are related to neutral gene genealogies via the well-known Ewens sampling formula. Simulations show rapid convergence to limiting analytical predictions as the strength of selection increases. These results extend the idea of a soft selective sweep to deleterious alleles and have implications for the interpretation of polymorphism among disease-causing alleles in humans.