cssi/SciSciGPT-SciSciNet huggingface dataset:
Phonon-assisted trapping and detrapping of an electron in quantum wells and wires by ionized impurity

Abstract We consider the capture and ionization of an electron in quantum wells and wires by a shallow donor impurity due to the interaction with acoustical phonons. In the caseof phonon wavelengthsmuch smaller than the width of wells or wires, L , the transition rates are proportional to ∈ -5 ( n ∈ +1/2±1/2) L -6 , where ∈ is the transferred energy and n ∈ is the phonon occupation number.
Doppler systemic venous flow patterns: Changes in children with mild/moderate pulmonic stenosis

To determine the usefulness of systemic venous flow patterns in patients with mild/moderate right ventricular hypertension, 17 patients with isolated mild/moderate pulmonic stenosis and 17 age-matched normal children were evaluated with pulsed Doppler echocardiography. Tricuspid valve, superior vena caval, and hepatic vein pulsed Doppler recordings were obtained with simultaneous respirometry and electrocardiography. Peak velocities and velocity-time integrals were measured for Doppler signals corresponding with ventricular systole, ventricular diastole, ventricular end systole, and atrial systole. The groups were similar in weight, heart rate, tricuspid inflow Doppler echocardiograms, and cardiac indexes. Compared with normal subjects, patients showed changes in respiratory variation for some superior vena caval and hepatic vein indexes. In addition, hepatic vein measurements made at ventricular end systole were significantly lower and measurements made at atrial systole were significantly higher in patients than in normal subjects. These changes in systemic venous flow patterns may provide a sensitive indicator of early right-sided heart dysfunction.
Genetics of Cerebrovascular Accidents

The influence of heredity factors in Cerebrovascular accidents was investigated by studying the families of 80 patients with a clinical diagnosis of CVA. The frequency of CVA in parents and siblings of these patients was compared with the frequency in the family of the patient's spouse. The frequency of recognized predisposing illnesses to CVA including hypertension, diabetes and heart disease was also studied. The patients and the spouses were excluded from the study population. Analysis of the data obtained on 160 parents and 384 sibs of the proband and on 140 parents and 336 sibs of the spouse revealed a frequency of CVA of 10.7% and 8.6% respectively. This difference was not statistically significant. However, when the sibs and parents were analyzed separately the difference between the sibs was significant (p < 0.025), suggesting the possibility that a small added risk of CVA existed for certain close relatives of a CVA victim. Besides an inherited tendency to CVA, other factors were considered to ac...
Group support systems user experiences

The Hawaii International Conference on System Sciences (HICSS) has a long history of support of evolving areas of research, such as groupware and group support systems, and the nurturing of these new concepts and ideas. Groupware is one of the research areas that has benefited from the interaction of researchers and practitioners at HICSS during the formal paper sessions, the information "birds of a feather" gatherings and at the daily receptions to discuss "pros" and "cons" and to share insights and information. Over the years these researchers and practitioners have led the way in their organizations to dramatically improve productivity and organizational efficiency and effectiveness. This mini-track will focus on user experience from real organizations and real problems. The technological and process advances gained through years of research and practical experience are shared by the authors of the 12 papers in the session. The following four sessions and papers describe the recent advances in groupware development and experiences. We are fortunate to assemble this group of authors and experts who are willing to share insights and knowledge gained from their experiences. The focus of each session is as follows: Session 1. Review of Case and Field Studies and a Description of two Field Studies in the Navy.Session 2. Distributed Facilitation: Tools, Techniques, Procedures and Lessons Learned.Session 3. Training Issues, User Experience in the Amsterdam Police Force and Brainstorming in Very Large Groups.Session 4. More User Experience Regarding Process Losses, Organizational Acceptance of New Technology and Web Groupware.The papers in this session describe efforts in process design, planning, development of practical guidelines for collaboration and creative problem solving issues.All of the papers and speakers bring insight and lessons learned to real world applications. The GroupSystems software will be available throughout the sessions to identify research questions and opportunities for further study.
Permanent Pacemaker Implantation Following Aortic Valve Replacement: Current Prevalence and Clinical Predictors

Background:The incidence of conduction disease requiring permanent pacemaker (PPM) implantation following aortic valve replacement (AVR) ranges from 3% to 6%. Data concerning the potential risks for PPM requirement associated with certain valve types have been conflicting and controversial. We sought to evaluate the prevalence, predictors for PPM implantation, and PPM dependency during follow-up in patients undergoing AVR. Methods:A total of 214 consecutive patients undergoing AVR were studied retrospectively. A total of 207 patients were included in the statistical analysis. Clinical variables including valve size and types were catalogued and the incidence of PPM evaluated. Cardiac rhythm device clinic records were examined and PPM dependency status was catalogued. Multivariate analyses were performed to determine predictors of PPM implantation and PPM dependency during follow-up. Results:Fifteen patients (7.2%) required PPM postoperatively. After controlling for clinical and surgical characteristics, predictors for PPM included preoperative first-degree atrioventricular block with and without left anterior fascicular block or intraventricular conduction delay [odd ratios (OR) = 12.5, P = 0.001], cardiac arrest postoperatively (OR = 9.4, P = 0.012), and combined aortic and mitral valve surgery (OR = 11.5, P = 0.027). Aortic valve types did not predict complete heart block (CHB) and PPM implantation. Of those patients who underwent PPM implantation, 70% were classified as PPM dependent during long-term follow-up. Conclusion:CHB and PPM implantation continue to be common complications of AVR. Preexisting atrioventricular with intrafascicular or intraventricular conduction disease along with cardiac arrest and dual valve surgery are the most important significant predictors of PPM implantation and PPM dependency during follow-up. The selection of valve types did not predict conduction disease requiring PPM implantation.
Hydrodesulfurization of thiophene over unsupported molybdenum carbide

Abstract Hydrodesulfurization (HDS) converts organic sulfur compounds to H 2 S and desulfurized organic compounds in the presence of H 2 . The most typical HDS catalysts consist of Mo Co supported on γ-alumina. Catalyst precursors are in the oxide form and are sulfided prior to use. It is believed that the Mo component of Mo Co S/Al 2 O 3 is the active species for HDS while the Co component serves as a chemical and/or structural promoter [1–4]. To understand better the nature of the HDS catalyst, Mo/Al 2 O 3 catalysts without Co were studied extensively by Massoth and co-workers. In particular, oxidized, prereduced or presulfided molybdenum samples were investigated as catalsyts for HDS of thiophene [5]. Here we present the results of thiophene HDS over unsupported molybdenum carbide, and we compare these results to those obtained on a presulfided Mo/Al 2 O 3 catalyst. To the best of our knowledge, precarburized molybdenum has never been studied as a HDS catalyst.
The associated disturbance-free system: A means for investigating the controllability of a disturbed system

This paper addresses the problem of state controllability in the presence of additive disturbances. In contrast to the stochastic controllability problem, the formulation given here does not require a probabilistic description of the uncertainty. Instead, the objective is to steer the state to the target in a so-called guaranteed sense. That is, one only assumes the availability of ana priori bounding setQ for the values of the uncertainty. Within this context, the goal is to decide whether one can find a control, having values restricted to a set Ω, which guarantees the transfer of the state to a prespecified target. Hence, we are led to define the notion of (Ω,Q)-controllability. The main result of this paper is given in Theorem 4.1. Loosely speaking, this theorem gives criteria for (Ω,Q)-controllability, which involve looking at the convergence properties of certain scalar-valued time functions which are created from the known data. In order to achieve this result, it is first shown that the given system (S x with its targetX(·) can be associated with another system (S Y) having targetY(·). Although (S x) has disturbances in its dynamical description, (S Y) is disturbance-free. Moreover, it is shown that (S x) is (Ω,Q)-controllable toX(·) if and only if (S Y) is Ω-controllable toY(·). After transforming the pair [(S x),X(·)] into [(S Y,Y(·)], one can use the known results (e.g., Ref. 1) on Ω-controllability of deterministic systems to determine the controllability properties of the system with disturbances. This line of thought motivates calling (S Y) the associated disturbance-free system. Finally, it is also shown how the required calculations can be greatly simplified for the special case of a polyhedral target.
Lifetimes of triplet state alkylbenzenes in the vapor phase

Abstract Rate constants for triplet state decay of C 6 H 6 , C 6 D 6 and 15 alkylbenzenes in the vapor phase have been found, using a flash-sensitized biacetyl phosphorescence technique, to range between 800 s −1 and ⩾ 18 000 s −1 . Only benzene has a significant positive activation energy for decay. Kinetic and spectroscopic evidence supports a photoisomerization decay channel in t -butylbenzene. Comparison of lifetimes with molecular size shows that increased density of rotational levels does not account for rapid decay of the triplet state. This contradicts a recent suggestion to explain short lifetimes of triplet state aromatic hydrocarbons in the vapor phase, relative to the long lifetimes of the same molecules in low temperat matrices. Evidence suggests that the dominant decay paths for triplet state alkylbenzenes are different in room temperature vapors and low temperature matrices.
Self-contained, fully integrated biochip for sample preparation, polymerase chain reaction amplification, and DNA microarray detection.

A fully integrated biochip device that consists of microfluidic mixers, valves, pumps, channels, chambers, heaters, and DNA microarray sensors was developed to perform DNA analysis of complex biological sample solutions. Sample preparation (including magnetic bead-based cell capture, cell preconcentration and purification, and cell lysis), polymerase chain reaction, DNA hybridization, and electrochemical detection were performed in this fully automated and miniature device. Cavitation microstreaming was implemented to enhance target cell capture from whole blood samples using immunomagnetic beads and accelerate DNA hybridization reaction. Thermally actuated paraffin-based microvalves were developed to regulate flows. Electrochemical pumps and thermopneumatic pumps were integrated on the chip to provide pumping of liquid solutions. The device is completely self-contained: no external pressure sources, fluid storage, mechanical pumps, or valves are necessary for fluid manipulation, thus eliminating possibl...
Uptake of glycerol-2-phosphate via the ugp-encoded transporter in Escherichia coli K-12.

During phenotypic characterization of various Escherichia coli mutants, we observed that ΔphoA strains are capable of using glycerol-2-phosphate (G2P) as a sole source of phosphorus. Mutations in the ugpBAECQ operon eliminated this phenotype, suggesting that G2P is a previously unrecognized substrate for the binding protein-dependent Ugp transporter.
Intravenous thrombolytic treatment of acute ischemic stroke associated with left atrial myxoma: A case report

There are few data available regarding the safety or efficacy of thrombolysis of acute ischemic stroke secondary to myxoma. We present a patient treated with intravenous recombinant tissue plasminogen activator who developed hemorrhage remote from the location of ischemic stroke. Intra-arterial local thrombolysis may be a preferable alternative because of greater risk of hemorrhage from occult tumor emboli or microaneurysms in these patients.
Disability Policy Must Espouse Medical as well as Social Rehabilitation

A confident statement in Social Inclusion by Mannon and MacLacLan that disability is not a health problem places doubt on the rationale of their otherwise well-written research agenda for disability studies. Both by definition and in practice disability is in part about the impact of health on a person's functioning. The consequence of this misperception among social policy makers is a decreased emphasis on the resources and research needed to build medical rehabilitation programs. This is especially true in lower resource countries where naive inclusion of medical rehabillitation within community based rehabilitation strategies has resulted in fewer resources and less expertise to deliver the distinctly different, and well validated services of a medical rehabilitation team. Any rational research agenda on disability must focus on disease and medical rehabilitation as well as the psychological, social, and environmental factors discussed in this article.
Salivary diagnostic tests

The guest editor of this special supplement to JADA provides an overview of salivary diagnostic testing and introduces the articles presented in this supplement to The Journal of the American Dental Association.
Monodisperse magnetite nanoparticle tracers for in vivo magnetic particle imaging

Abstract Magnetic Particle Imaging (MPI) is a new biomedical imaging modality that produces real-time, high-resolution tomographic images of superparamagnetic iron oxide (SPIO) nanoparticle tracer distributions. In this study, we synthesized monodisperse tracers for enhanced MPI performance and investigated both, their blood clearance time using a 25 kHz magnetic particle spectrometer (MPS), and biodistribution using a combination of quantitative T2-weighted MRI and tissue histology. In vitro and in vivo MPI performance of our magnetic nanoparticle tracers (MNTs), subject to biological constraints, were compared to commercially available SPIOs (Resovist). Monodisperse MNTs showed a 2-fold greater signal per unit mass, and 20% better spatial resolution. In vitro evaluation of tracers showed that MPI performance of our MNTs is preserved in blood, serum-rich cell-culture medium and gel; thus independent of changes in hydrodynamic volume and fluid viscosity – a critical prerequisite for in vivo MPI. In a rodent model, our MNTs circulated for 15 min – 3× longer than Resovist – and supported our in vitro evaluation that MPI signal is preserved in the physiological environment. Furthermore, MRI and histology analysis showed that MNTs distribute in the reticuloendothelial system (RES) in a manner similar to clinically approved SPIO agents. MNTs demonstrating long-circulation times and optimized MPI performance show potential as angiography tracers and blood-pool agents for the emerging MPI imaging modality.
Signal design for noncoherent PPM modulation with applications to UWB communications

By deriving the probability of error of a binary pulse-position modulated (PPM), ultra wide-band (UWB) impulse-radio system under noncoherent detection, it is shown that the optima! value for time shift parameter /spl delta/ for PPM is fundamentally different from that for coherent reception. In particular, the optimal choice of /spl delta/ is one that results in zero correlation between the two waveforms used in PPM modulation. By examining the performance sensitivity around possible optimal /spl delta/ solutions for a commonly used UWB monopulse, we also show that it is still possible to employ /spl delta/<T/sub w/, where T/sub w/ is the UWB monopulse width, yet achieve optimal and robust performance.
Repair of Fascial Defects in Dogs Using Carbon Fibers

Hernia repair may involve the use of an implant to augment or replace autologous tissue, but the best material for use in this application has not been established. We developed a dog model to evaluate the mechanical strength of fascial defects repaired using carbon fibers, compared with the strength of similar defects repaired using polypropylene mesh (Marlex). Unrepaired defects were included as an additional control. Bilateral defects (1 cm square) were made in the fascia of the back, and the ultimate mechanical strength and stiffness at the repair sites were measured 3-12 months after operation. Defects repaired with carbon fibers were significantly stronger 12 months after operation compared with defects repaired with polypropylene mesh and compared with unrepaired defects. It is concluded that carbon fibers are biocompatible and significantly increase mechanical strength at the repair site. A randomized clinical trial involving patients undergoing hernia repair seems justified to determine whether carbon fibers are superior to standard therapy.
Ultrastructure synthesis of special architectures for photonic applications: high-frequency electro-optic modulators and high-density optical memories

A major requirement for polymeric electro-optic materials is that they must possess noncentrosymmetric (roughly uniaxial) order of chromophores in the bulk material. Thermodynamic relaxation of this chromophore alignment is prevented by raising the glass- transition temperature of the polymeric materials during the electric-field poling process. This is accomplished by (1) thermal imidization of a poly(amic acid) prepolymer, (2) thermally induced chemical crosslinking of an acrylate-type prepolymer, prepared from chromophores containing differing reactive functionalities, (3) sol-gel processing of alkoxysilane- incorporated chromophores, and (4) thermosetting polyurethane/polyurea materials. Analogs of these chromophores that contain reversible photoactive moieties are attached to the surface of functionalized polystyrene and polyacrolein beads permitting the realization of room temperature persistent spectral hole burning exploiting morphology-dependent resonances. Such resonances provide the basis of wavelength coding for the development of three and four-dimensional high-density optical memories.
Apocalypse not: a commentary on destination maturation models

Tourism destination maturation models, patterned as they are after marketing’s Product Life Cycle, are inherently negative as they predict a ‘devil’s bargain’; with tourism success leading to tourism growth and undesirable change for the community. This commentary considers the implications of these models and suggests that with effective destination management and appropriate marketing that the inevitability of demise, as predicted by these models, can be averted.
Are Pediatricians Qualified to Judge Suicide Gestures

The statements of the Committee on Adolescence of the American Academy of Pediatrics regarding teenage suicide (Pediatrics 66:144, 1980) are, in my opinion, quite controversial as far as the recommendations of patient evaluation are concerned. Specifically, the statement that some patients who make suicide gestures may be evaluated and followed by a pediatrician, is unsound. Pediatricians are not trained to evaluate and treat psychotic patients and are not adequately trained to evaluate the psychiatric problems of the adolescent who makes a suicide gesture.
Three field experiments on the effects of violations of conversational distance

The effects of interpersonal reward and violations of conversational distancing expectations on compliance and interaction behaviors were tested in three retail shopping settings. Subjects were salespeople (N = 70, N = 49, N = 104) who were approached by confederates posing as customers or students conducting interviews on consumer behavior. Two levels of interpersonal reward (high versus low levels of apparent status, attractiveness, purchasing power and/or expertise) and three levels of distance (close violation, norm, far violation) were manipulated. Results showed high reward to induce more compliance with a request and more favorable interaction patterns than low reward. Distance violations evoked more arousal, activation and apparent distraction, while the favorability of reactions to distance violations tended to vary by reward level, as expected. Confounding effects of gender, confederate communication style, and possible nonverbal norms for compensation and reciprocity are also discussed.
Compensation of longitudinal coupled-bunch instability in the Advanced Photon Source storage ring

A longitudinal coupled-bunch (CB) instability was encountered in the 7-GeV storage ring. This instability was found to depend on the bunch fill pattern as well as on the beam intensity. The beam spectrum exhibited a coupled-bunch signature, which could be reproduced by an analytical model. The oscillations were also observed on a horizontal photon monitor. The beam fluctuations exhibited two periodicities, which were found to be correlated with the rf cavity temperatures. This correlation is consistent with the measured temperature dependence of the higher-order mode (HOM) frequencies. The HOM impedance drives the beam when brought into resonance with the CB mode by the temperature variation. Increasing the inlet cavity water temperature suppressed the instability. The experimental results are compared to an analytical model which characterizes the fill-pattern dependence. Studies to identify the offending HOMs are also presented.
Compartmental analysis of the disposition of benzo[a]pyrene in rats.

We have previously reported the disposition of benzo[a]pyrene (B[a]P) and its metabolites in male Sprague-Dawley rats following intratracheal instillation of [3H]B[a]P [Weyand, E.H. and Bevan, D.R. (1986) Cancer Res., 46, 5655-5661]. In some experiments, cannulas were implanted in the bile duct of the animals prior to administration of [3H]B[a]P [Weyand, E.H. and Bevan, D.R. (1987) Drug Metab. Disposition, 15, 442-448]. Based on these data, we have developed a compartmental model of the distribution of radioactivity to provide a quantitative description of the fate of B[a]P and its metabolites in rats. Modeling of the distribution of radioactivity was performed using the Simulation, Analysis and Modeling (SAAM) and conversational SAAM (CONSAM) computer programs. Compartments in the model included organs into which the largest amounts of radioactivity were distributed as well as pathways for excretion of radioactivity from the animals. Data from animals with and without cannulas implanted in the bile duct were considered simultaneously during modeling. Radioactivity was so rapidly absorbed from the lungs that an absorption phase into blood was not apparent at the earliest sampling times. Using the model of extrapolate to shorter times, it was predicted that the maximum amount of radioactivity was present in blood within 2 min after administration. In addition, considerable recycling of radioactivity back to lungs from blood was predicted by the model. Transfer of radioactivity from blood to liver and carcass (skin, muscle, bones, fat and associated blood) also was extensive. Carcass was modeled as the sum of two compartments to obtain agreement between the model and experimental data. The model accounted for enterohepatic circulation of B[a]P metabolites; data also required that intestinal secretion be included in the model. Quantitative data obtained from compartmental analysis included rate constants for transfer of radioactivity among compartments as well as statistical parameters indicating the identifiability of the rate constants. That the model is consistent with two sets of data, those obtained in animals with and without a biliary cannula, indicates its potential utility in predicting the disposition of B[a]P and its metabolites in vivo.
Antibody is required for clearance of infectious murine hepatitis virus A59 from the central nervous system, but not the liver.

Intracerebral inoculation with mouse hepatitis virus strain A59 results in viral replication in the CNS and liver. To investigate whether B cells are important for controlling mouse hepatitis virus strain A59 infection, we infected muMT mice who lack membrane-bound IgM and therefore mature B lymphocytes. Infectious virus peaked and was cleared from the livers of muMT and wild-type mice. However, while virus was cleared from the CNS of wild-type mice, virus persisted in the CNS of muMT mice. To determine how B cells mediate viral clearance, we first assessed CD4 + T cell activation in the absence of B cells as APC. CD4 + T cells express wild-type levels of CD69 after infection in muMT mice. IFN-γ production in response to viral Ag in muMT mice was also normal during acute infection, but was decreased 31 days postinfection compared with that in wild-type mice. The role of Ab in viral clearance was also assessed. In wild-type mice plasma cells appeared in the CNS around the time that virus is cleared. The muMT mice that received A59-specific Ab had decreased virus, while mice with B cells deficient in Ab secretion did not clear virus from the CNS. Viral persistence was not detected in FcR or complement knockout mice. These data suggest that clearance of infectious mouse hepatitis virus strain A59 from the CNS requires Ab production and perhaps B cell support of T cells; however, virus is cleared from the liver without the involvement of Abs or B cells.
UTMC'S LSI CAD System - HIGHLAND

The HIGHLAND [1] integrated logic design system, for the design of gate array and standard cell IC's is described. While the main system features are reviewed, the major emphasis is on system software control and release issues.
Towards the creation of a flexible classification scheme for voluntarily reported transfusion and laboratory safety events

Background: Transfusion and clinical laboratory services are high-volume activities involving complicated workflows across both ambulatory and inpatient environments. As a result, there are many opportunities for safety lapses, leading to patient harm and increased costs. Organizational techniques such as voluntary safety event reporting are commonly used to identify and prioritize risk areas across care settings. Creation of functional, standardized safety data structures that facilitate effective exploratory examination is therefore essential to drive quality improvement interventions. Unfortunately, voluntarily reported adverse event data can often be unstructured or ambiguously defined. Results: To address this problem, we sought to create a “best-of-breed” patient safety classification for data contained in the Duke University Health System Safety Reporting System (SRS). Our approach was to implement the internationally recognized World Health Organization International Classification for Patient Safety Framework, supplemented with additional data points relevant to our organization. Data selection and integration into the hierarchical framework is discussed, as well as placement of the classification into the SRS. We evaluated the impact of the new SRS classification on system usage through comparisons of monthly average report rates and completion times before and after implementation. Monthly average inpatient transfusion reports decreased from 102.1 ± 14.3 to 91.6 ± 11.2, with the proportion of transfusion reports in our system remaining consistent before and after implementation. Monthly average transfusion report rates in the outpatient and homecare environments were not significantly different. Significant increases in clinical lab report rates were present across inpatient and outpatient environments, with the proportion of lab reports increasing after implementation. Report completion times increased modestly but not significantly from a practical standpoint. Conclusions: A common safety vocabulary can facilitate integration of information from disparate systems and processes to permit meaningful measurement and interpretation of data to improve safety within and across organizations. Formation of a “best-of-breed” classification for voluntary reporting necessitates an internal examination of localized data needs and workflow in order to design a product that enables comprehensive data capture. A team of clinical, safety, and information technology experts is necessary to integrate the data structures into the reporting system. We have found that a “best-of-breed” patient safety classification provides a solid, extensible model for adverse event analysis, healthcare leader communication, and intervention identification.
Distributed coding of multispectral images: a set theoretic approach

Distributed coding problem poses the challenge of how to shift the exploitation of the correlation structure of source from encoder to decoder with minimal degradation on coding efficiency. In this paper, we propose a novel convex-set theoretic framework for distributed coding of multispectral images. Alternating projection based decoding algorithms are developed to exploit the correlation among different spectral channels at the centralized decoder. Both asymmetric and symmetric protocols are studied and compared. Experiment results have shown that the proposed symmetric distributed coder only falls behind standard wavelet coders (e.g., JPEG2000) by less than 2 dB at the bit rate of 1-2 bpp.
Searching for Complex Patterns Using Disjunctive Anomaly Detection

We extend Disjunctive Anomaly Detection (DAD) algorithm to handle various data distributions and models of cluster interactions. It enables efficient searching and explanation of multiple disease outbreaks occurring simultaneously. Detected clusters can span multiple values along multiple dimensions, and can impact any subset of dimensions in data. This type of search is known to be exponentially complex, so DAD uses approximations to enable fast processing of large data. We demonstrate DAD's ability to systematically outperform state-of-art alternatives including What's Strange About Recent Events (WSARE) and Large Average Submatrix (LAS) on data of scales and complexities typically encountered in biosurveillance applications.
Methods for studying tooth root cementum by light microscopy.

The tooth root cementum is a thin, mineralized tissue covering the root dentin that is present primarily as acellular cementum on the cervical root and cellular cementum covering the apical root. While cementum shares many properties in common with bone and dentin, it is a unique mineralized tissue and acellular cementum is critical for attachment of the tooth to the surrounding periodontal ligament (PDL). Resources for methodologies for hard tissues often overlook cementum and approaches that may be of value for studying this tissue. To address this issue, this report offers detailed methodology, as well as comparisons of several histological and immunohistochemical stains available for imaging the cementum–PDL complex by light microscopy. Notably, the infrequently used Alcian blue stain with nuclear fast red counterstain provided utility in imaging cementum in mouse, porcine and human teeth. While no truly unique extracellular matrix markers have been identified to differentiate cementum from the other hard tissues, immunohistochemistry for detection of bone sialoprotein (BSP), osteopontin (OPN), and dentin matrix protein 1 (DMP1) is a reliable approach for studying both acellular and cellular cementum and providing insight into developmental biology of these tissues. Histological and immunohistochemical approaches provide insight on developmental biology of cementum.
Evolution of Eye Regression in the Cavefish Astyanax: Apoptosis and the Pax-6 Gene'

SYNOPSIS. The eye is an extraordinary organ in terms of its development and evolution. In cave animals, the eye is sometimes reduced or eliminated as a consequence of adaptation to life in perpetual darkness. We have used the characid teleost Astyanax mexicanus as a model system to investigate the mechanisms of eye degeneration during the evolution of a cave vertebrate. Eyed surface populations of Astyanax entered caves during the Pleistocene, and their descendants lost their eyes and pigmentation. Astyanax populations exhibiting various degrees of eye regression have been reported in 29 Mexican caves. Surface populations with characteristics of the ancestral stock still exist in the vicinity of these caves. Thus, Astyanax represents one of the few instances in which the ancestral (surface fish) and the derived (cavefish) developmental modes are extant and available for comparative studies. The cavefish embryo develops an optic primordium consisting of a lens vesicle and optic cup but the rudimentary eye arrests in development and degenerates. Here we report that eye degeneration is accompanied by extensive apoptosis and downregulation of the Pax-6 gene in the developing lens. The results suggest that alterations in lens development are important factors in eye regression during cavefish evolution.
Isolation and Characterization of Griffithsin, a Novel HIV-inactivating Protein, from the Red Alga Griffithsia sp.

Abstract Griffithsin (GRFT), a novel anti-HIV protein, was isolated from an aqueous extract of the red alga Griffithsia sp. The 121-amino acid sequence of GRFT has been determined, and biologically active GRFT was subsequently produced by expression of a corresponding DNA sequence in Escherichia coli. Both native and recombinant GRFT displayed potent antiviral activity against laboratory strains and primary isolates of T- and M- tropic HIV-1 with EC50 values ranging from 0.043 to 0.63 nm. GRFT also aborted cell-to-cell fusion and transmission of HIV-1 infection at similar concentrations. High concentrations (e.g. 783 nm) of GRFT were not lethal to any tested host cell types. GRFT blocked CD4-dependent glycoprotein (gp) 120 binding to receptor-expressing cells and bound to viral coat glycoproteins (gp120, gp41, and gp160) in a glycosylation-dependent manner. GRFT preferentially inhibited gp120 binding of the monoclonal antibody (mAb) 2G12, which recognizes a carbohydrate-dependent motif, and the (mAb) 48d, which binds to CD4-induced epitope. In addition, GRFT moderately interfered with the binding of gp120 to sCD4. Further data showed that the binding of GRFT to soluble gp120 was inhibited by the monosaccharides glucose, mannose, and N-acetylglucosamine but not by galactose, xylose, fucose, N-acetylgalactosamine, or sialic acid-containing glycoproteins. Taken together these data suggest that GRFT is a new type of lectin that binds to various viral glycoproteins in a monosaccharide-dependent manner. GRFT could be a potential candidate microbicide to prevent the sexual transmission of HIV and AIDS.
Rodent neurotoxicity bioassays for screening contaminated great lakes fish

Standard laboratory rat neurotoxicity protocols were used to study the consequences resulting from the consumption of walleye (Stizostedion vitreum), whitefish (Coregonus clupeaformis), and lake trout (Salvelinus namaycush) from Lake Superior (LS) and the consumption of carp (Cyprinus carpio) from Little Lake Butte des Morte (LLBM) near Oshkosh, Wisconsin, USA. Two 90-d subchronic studies are described, including a 45-d exposure to fish diets using male Sprague-Dawley hooded rats, and a 90-d exposure to fish diets using female rats of the same species. Behavioral alterations were tested using a battery of behavioral tests. In addition, pharmacologic challenges using apomorphine and D-amphetamine were administered to the rats to reveal latent neurotoxic effects. Cumulative fish consumption data were recorded daily, weight gain recorded weekly, and behavior data collected prior to exposure, and on days 7, 14, 55 {+-} 2, 85 {+-} 2. Motor activity data were collected on days 30 {+-} 2, 60 {+-} 2, and 90 {+-} 2 of the feeding protocols. Brain tissue from rodents fed these fish were subsequently analyzed for either mercury (Hg) or polychlorinated biphenyls (PCB). Mercury concentrations were increased in the brains of the walleye-fed rats, and PCB concentrations ranged from 0.5 nl/L to 10 nl/L in themore » brains of rats fed carp from LLBM, a Lake Michigan tributary. Adult male rats fed LLBM carp for 45 d exhibited the greatest behavior responses to the dopaminergic agonist apomorphine on the accelerating rotarod, although these differences were not significant. The 90-d exposure of LS walleye or Hg-spiked LS walleye resulted in behavior alterations on tactile startle response and second footsplay. D-Amphetamine challenge caused changes in tactile startle response, second footsplay, and accelerating rotarod performance after consuming walleye diets. Rats fed LLBM carp had altered behavioral responses to apomorphine on the accelerating rotarod.« less
Creditor Control Rights, Corporate Governance, and Firm Value

We provide evidence that creditors play an active role in the governance of corporations well outside of payment default states. By examining the SEC filings of all U.S. nonfinancial firms from 1996 through 2008, we document that, in any given year, between 10 percent and 20 percent of firms report being in violation of a financial covenant in a credit agreement. We show that violations are followed immediately with a decline in acquisitions and capital expenditures, a sharp reduction in leverage and shareholder payouts, and an increase in CEO turnover. The changes in the investment and financing behavior of violating firms coincide with amended credit agreements that contain stronger restrictions on firm decision-making; changes in the management of violating firms suggest that creditors also exert informal influence on corporate governance. Finally, we show that firm operating and stock price performance improve following a violation. We conclude that actions taken by creditors increase the value of theaverage violating firm.
Managing the Incidence of Sickle Cell Anemia Through Genetic Counseling

Genetic counseling has long held promise as a means for controlling Tay-Sachs disease, thalassemia, sickle cell anemia, and a host of other untreatable genetic illnesses. This paper reports a study to investigate the long-term viability of genetic counseling as an alternative to searching for a cure for sickle cell anemia. The paper includes consideration of the relative lack of fitness of individuals with sickle cell anemia, the effect of mutation from normal to sickle hemoglobin, and the effect of interbreeding between the black and white races as well as the result of counseling specific proportions of the population with high risk rather than counseling everyone. The results project the theoretical rate of sickle cell anemia in the U.S. black population over the next 800 years, and are viewed qualitatively rather than as firm projections due to the preliminary nature of the counseling data and the simplifying assumptions of the model. They suggest that counseling programs can play a very large role in reducing the incidence of sickle cell anemia, even in the near future.
Reid on the first principles of morals

What role do the first principles of morals play in Reid's moral theory? Reid has an official line regarding their role, which identifies these principles as foundational propositions that evidentially ground other moral propositions. I claim that, by Reid's own lights, this line of thought is mistaken. There is, however, another line of thought in Reid, one which identifies the first principles of morals as constitutive of moral thought. I explore this interpretation, arguing that it is a fruitful way of understanding much of what Reid wants to say about the role of moral first principles and drawing some connections between it and recent work on moral nonnaturalism.
Transformation of the oak forest spatial structure in the Minneapolis/St. Paul metropolitan area, Minnesota, USA over 7 years

The Twin Cities Metropolitan Area (TCMA) oak (Quercus spp.) forest area decreased by 5.6% between 1991 and 1998. Accompanying spatial transformation of the forest can have great impacts on forest health, water flow and quality, wildlife habitat, potential for the spread of invasive species, and the quality of life of urban residents. The types of spatial transformation that occurred along with the loss of oak forest in the TCMA were investigated through the integration of remote sensing, a Geographic Information System (GIS), and landscape and patch metrics in seven ecological subsections between 1991 and 1998. Oak forest patches in the TCMA as a whole decreased in area, number, and complexity. Fragmentation of oak forest took place in all subsections and attrition occurred in three subsections. Knowledge of how the oak forest has changed over time can be integrated with land use change information to help planners make decisions about zoning and development that will minimize the impacts of increasing land conversion pressure on forest areas.
Analyzing Functional Connectivity Using a Network Likelihood Model of Ensemble Neural Spiking Activity

Analyzing the dependencies between spike trains is an important step in understanding how neurons work in concert to represent biological signals. Usually this is done for pairs of neurons at a time using correlation-based techniques. Chornoboy, Schramm, and Karr (1988) proposed maximum likelihood methods for the simultaneous analysis of multiple pair-wise interactions among an ensemble of neurons. One of these methods is an iterative, continuous-time estimation algorithm for a network likelihood model formulated in terms of multiplicative conditional intensity functions. We devised a discrete-time version of this algorithm that includes a new, efficient computational strategy, a principled method to compute starting values, and a principled stopping criterion. In an analysis of simulated neural spike trains from ensembles of interacting neurons, the algorithm recovered the correct connectivity matrices and interaction parameters. In the analysis of spike trains from an ensemble of rat hippocampal place cells, the algorithm identified a connectivity matrix and interaction parameters consistent with the pattern of conjoined firing predicted by the overlap of the neurons' spatial receptive fields. These results suggest that the network likelihood model can be an efficient tool for the analysis of ensemble spiking activity.
Seasonal and geographic variation in territorial conflicts by male red-backed salamanders

We studied seasonal and geographic variation in the territorial behaviour of male red-backed salamanders, Plethodon cinereus. We examined tail loss in the forest and aggressive and submissive behaviour in the laboratory during summer (non-courtship season) and spring and autumn (courtship seasons) at two localities in Virginia, USA. In both populations, the proportion of tail loss was highest during the spring, while aggression was higher in the summer than in the spring or autumn. Thus, aggression was not directly associated with male–male contests for females or to tail loss. Secondly, we examined geographic variation using males from eight populations varying in elevation, genetic relatedness (two genetic groups), and presence/absence of similar-sized congeners. Behaviour differed based on elevation and genetic group: residents from lower elevations were more submissive and males from one genetic group were more submissive than those from a second genetic group. Therefore, resident-intruder behaviour varied seasonally and geographically.
Cut growth in vulcanizates of natural rubber, cis-polybutadiene, and a 50/50 blend during single and repeated extension

Abstract A typical passenger sidewall composition was employed using three elastomer systems NR, BR, and a 50/50 blend of NR and BR. Tensile strips with edge cuts of various depths were strained in...
Effect of mast cell granules on heparin-activated tissue lipase.

SummaryMast cell granules inhibited a heparin activated lipase extracted from rat adipose tissue. Purified rat heparin extracted from granules activated the lipase. Since DFP reversed the inhibition by both chymotrypsin and mast cell granules, it was concluded that granule-bound, mast cell chymase was responsible for the inhibition of lipase activity by mast cell granules. The stability of the chymase-heparin complex in extracellular and intravascular compartments makes it unlikely that mast cell heparin modulates lipase activity in tissue or plasma.
Dynamic polariton condensation in a single GaN nanowire-dielectric microcavity

We have experimentally investigated the dynamic polariton condensation behavior in a single GaN nanowire strongly coupled to a dielectric microcavity under nonresonant optical excitation. Both time-integrated and time-resolved polariton luminescence measurements have been made in the temperature range of 25 to 100 K (corresponding to exciton-cavity photon detuning of \ensuremath{-}3.0 to $+$4.2 meV). Polariton lasing is observed in the entire temperature range, with the lowest threshold energy of 57 nJ/cm${}^{2}$ measured at 50 K (\ensuremath{\delta} $=$ \ensuremath{-}1.3 meV). All the measurements indicate that at the lower temperatures the degenerate polariton condensate is not in thermal equilibrium with the phonon bath. At 85 and 100 K (\ensuremath{\delta} $=$ $+$2.3 and 4.2 meV), the system attains a state close to thermal equilibrium via dynamic Bose condensation. The best results are obtained at ${T}_{\mathrm{latt}}$ $=$ 85 K, for which ${T}_{\mathrm{LP}}$ $=$ 88.8 K, and this is the highest temperature recorded for an equilibrium phase transition in exciton-polariton condensates.
Aerodynamic Control of a Dynamically Pitching VR-12 Airfoil using Discrete Pulsed Actuation

Transitory control and regulation of the aerodynamic loads on a static and dynamically pitching VR-12 airfoil is investigated in wind tunnel experiments. Actuation is effected using a spanwise array of integrated combustion-based actuators that are triggered intermittently relative to the airfoil’s motion, producing high-impulse actuation jets on characteristic time scales that are an order of magnitude shorter than the airfoil’s convective time scale. Poststall transitory actuation leads to a momentary reattachment of the flow over the airfoil, and the effects of pulse sequencing on the aerodynamic characteristics of the airfoil are assessed using time-resolved measurements of the lift force and pitching moment coupled with particle image velocimetry that is acquired phased-locked to the actuation waveform. The present investigations show that the aerodynamic loading can be significantly altered by a number of actuation programs using strategically placed bursts during the pitch cycle. While actuation during the upstroke primarily affects the formation, evolution, and advection of the dynamic stall vortex, actuation during the downstroke accelerates flow attachment. Superposition of such actuation programs can lead to enhancement of cycle lift and pitch stability, and reduced cycle hysteresis.
Application of Gray Relative Analysis on Data Processing of Automobile Subjective Evaluation

This paper introduces the theory of Gray System and Gray Relative Analysis,developed the new method of da-ta processing of automobile subjective evaluation based on Gray Relative Analysis.The instance shows the method is effec tive,the comprehensive analysis of subjective evaluation data is completed,and the design load reference of benchmark vehicle has been obtained.