cssi/SciSciGPT-SciSciNet huggingface dataset:
Electrostatic Control of Excitonic Energies and Dynamics in a CdS Quantum Dot through Reversible Protonation of Its Ligands

This paper describes the pH dependence of the excitonic energies and dynamics of CdS quantum dots (QDs) capped with phosphonopropionate (PPA) in water. QDs capped with PPA carry a negative charge on their surfaces upon deprotonation of PPA above pH ∼ 8.5; the resultant electric field induces large changes in the QD’s optical properties. Between pH 5.6 and 12.0, an increase in pH is accompanied by a 47-meV bathochromic shift in the bandgap of the QDs and a decrease in the Stokes shift by ∼4.3 meV/pH unit. An increase in the radiative recombination rate by a factor of 20.9 occurs on increasing the pH from 5.6 to 9.4. These observations are attributed to a shifting of the energy levels within the first exciton manifold, and are simulated using time-dependent density functional theory calculations on model Cd29S29 clusters surrounded by point charges.
Vermont Hub-and-Spoke Model of Care for Opioid Use Disorder: Development, Implementation, and Impact.

Background Opioid use disorders (OUDs) are reaching epidemic proportions in the United States, and many geographic areas struggle with a persistent shortage in availability of opioid agonist treatment. Over the past 5 years, Vermont addiction medicine physicians and public health leaders have responded to these challenges by developing an integrated hub-and-spoke opioid treatment network. Methods In the present report, we review the development, implementation, and impact of this novel hub-and-spoke model for expanding OUD treatment in Vermont. Results Vermont's hub-and-spoke system has been implemented state-wide and well-received by providers and patients alike. Adoption of this model has been associated with substantial increases in the state's OUD treatment capacity, with Vermont now having the highest capacity for treating OUD in the United States with 10.56 people in treatment per 1000. There has been a 64% increase in physicians waivered to prescribe buprenorphine, a 50% increase in patients served per waivered physician, and a robust bidirectional transfer of patients between hubs and spokes based upon clinical need. Challenges to system implementation and important future directions are discussed. Conclusions Development and implementation of a hub-and-spoke system of care has contributed substantially to improvements in opioid agonist treatment capacity in Vermont. This system may serve as a model for other states grappling with the current opioid use epidemic.
Microscopic scale interactions of water ions at crude oil/water interface and their impact on oil mobilization in advanced water flooding

Abstract In this study, we performed interfacial shear rheology, surface potential and oil droplets coalescence time measurements to investigate microscopic scale interactions of various individual water ions at both air-water and crude oil-water interfaces. The measured interfacial rheology data indicated completely different interfacial behavior at crude oil-water interface when compared to air-water interface due to the presence of crude oil functional groups. Viscous dominated response was observed at crude oil-water interface for all brine compositions. Lower interfacial viscous modulus was observed for certain key ions such as calcium, and magnesium. The interfacial viscous modulus was found to be substantially much higher for sulfates, besides exhibiting some elasticity. The surface potential was gradually decreased by replacing seawater with calcium only brine. The better surface activity with seawater can be attributed to adsorption of more key water ions at the surface. These interesting results observed with calcium and magnesium ions at crude oil-water interface are expected to favorably impact oil mobilization in advanced water flooding processes. Such favorable interactions can quickly destabilize the interfacial film between oil and water (due to less viscous interfaces) to promote the coalescence between released oil droplets and enable faster oil mobilization. This coalescence process is also sequential and it would continue until the formation of small oil bank. The coalescence times measured between oil droplets confirmed the adverse impact of sulfate ions, to hinder the coalescence and delay oil mobilization, in consistent with interfacial shear rheology results. The new fundamental knowledge gained in this study would provide an important guidance on how to synergize water ion interactions at fluid-fluid interfaces with those at rock-fluids interfaces and optimize advanced water flooding processes in carbonate reservoirs.
Illustrations of the Use of a Truncated Sequential t-Test

In situations where the cost of sampling is high, sequential procedures may be used to reduce this cost. However, many of these procedures have a number of undesirable drawbacks, such as the possibility that an extremely large sample size may be needed ..
Techniques for Creating and Using Web Questionnaires in Research and Teaching

Publisher Summary This chapter focuses on the techniques and procedures that are used for putting questionnaires on the Web, with particular emphasis on the technical details. Interactive questioning can be programmed so that it can be described clearly and replicated. In this regard, the method is similar to computer-assisted telephone interviewing, but it is much less expensive. Included here are error checking, challenges to past responses, and use of practice trials with feedback about them. It is easier to make sure that subjects answer all the questions, give answers in the appropriate range, and meet minimal conditions on ordering. Also, Web questionnaires make it much easier to have students to collect and analyze data, as a teaching exercise. However, server-side programs must be carefully written in order not to make the server vulnerable to break-ins, so it is best to consult your local system administrator for advice about which program to use.
Linking the Population to the Environment

Understanding environmental causes of changes in the state of the health requires information on the parts of the environment, the sources of environmental pollutants into these parts, how pollutants move through those parts, how the parts are interconnected, and how we can characterize those parts to predict the degree of hazard posed by the pollutant. This section provides an overview of principles of environmental analysis. The goal is to understand environmental systems in enough detail to see how specific aspects of the environment bring people into contact with particular pollutants. In analyzing the environment in ways useful in environmental health science, we will focus on several ideas central to environmental science: compartments, media, pollutants, dispersion, interconnections between compartments, variability of properties throughout a compartment, evolution of properties in time and exposure.
MSCs for Diabetes

Mesenchymal stromal cells (also often referred to as mesenchymal stem cells, MSCs) hold promise as a powerful tool in the treatment of human diseases. Because of their potent immunomodulatory properties, they are likely to impact in a positive fashion diseases in which inflammation and/or autoimmunity play a key role. Furthermore, they have been shown to possess plasticity as precursors of cells of various types. Their differentiation potential could span cell differentiation products that do not normally derive from the mesoderm, including cells of endodermal origin. These two remarkable features make them potentially ideal candidates for regenerative approaches. This chapter will briefly discuss the current state of the art in the emerging field of their use for autoimmune type 1 diabetes.
Thermal Influence in the Diurnal Pressure Wave

The mean diurnal pressure curve was computed separately for days with large and for days with small ranges of temperature. Harmonic analysis of the two curves shows that the amplitude of the semidiurnal, as well as the diurnal, component is larger on days with large range of temperature. The semidiurnal maxima occur earlier on days with small temperature range.
Role of Abdominal US in Diagnosis of NEC

Current assessment for and diagnosis of necrotizing enterocolitis (NEC) remain inadequate. The introduction of interrogating bowel with ultrasound when NEC is suspected or when NEC has occurred presents greater opportunity to characterize the physical changes that have occurred in the bowel wall structures. The evaluation of bowel by ultrasound has been shown to have high specificity for bowel necrosis. There are current barriers in adoption of these techniques because they have not been integrated into routine diagnostic imaging and are not well incorporated in neonatal medicine.
GG-06 Integrative analysis of multi-omics data in an ethnically diverse lupus cohort identifies distinct molecular subtypes of SLE

Background Systemic Lupus Erythematous (SLE) is chronic autoimmune disease with heterogeneous disease manifestations and outcomes. We aimed to define how molecular differences underlie this clinical heterogeneity through an integrative approach leveraging methylation, genetic and phenotypic data from a well characterized multiethnic cohort of SLE patients. Methods 274 participants were studied. We defined our phenotypic outcomes by clustering analyses. We performed principal component analysis on the ACR clinical criteria and used the top 2 eigenvectors as input for K-means clustering. We identified stable clusters based on a stability score >0.8 determined by a bootstrap resampling method. Our predictors were DNA methylation and genetic variation. DNA extracted from blood was analyzed on the illumina EPIC Beadchip. Single nucleotide polymorphism (SNP) genotype data was generated on the Affymetrix LAT1 World Array. Multivariate linear regression adjusting for population stratification, cell composition, sex, smoking history, and age was used to identify differentially methylated CpGs across clinical ACR criteria. We then investigated whether the differentially methylated CpG were under genetic control in a methylation quantitative trait loci analyses (cis-meQTLs). Results We identified three stable clusters based on ACR criteria. Cluster 1 was characterized by a higher proportion of participants of white ethnicity with malar rash, photosensitivity, serositis, arthritis, oral ulcers and fewer subserologies. Cluster 2 was characterized by a higher proportion of lupus nephritis and anti-dsDNA antibodies. Cluster 3 was characterized by higher proportion of hematologic manifestations, lupus nephritis, anti-dsDNA and anti-Sm antibodies. We identified 196 CpGs in 107 genomic regions that were differentially methylated between the clusters (FDR Conclusion Overall, we identified three clinical relevant clusters in a multiethnic SLE cohort. The three clusters could be differentiated by 196 CpGs of which 97 were under genetic control and enriched for IFN-gamma and IFN-alpha responsive genes. This work helps to elucidate the epigenetic and genetic mechanism behind the role of Type 1 interferon in SLE pathology.
Cannabinoid agonists for chronic neuropathic pain: randomised, crossover, double blind study

Cannabinoid agonists help in nausea and vomiting induced by chemotherapy, but are they effective for pain? Elizabeth Loder looks at a study that compared a cannabinoid agonist with a weak opioid
Using the Ideas and Approaches: A Case Study

A central premise of the book is that it is targeted to scholar/practitioners. Therefore, the inclusion of a detailed case study is important. The study presented here is of a project that sought to implement a culture change in a hi-tech support organization. It outlines the history of the business/cultural need giving rise to the project. It includes descriptions of how the project process was designed, conducted, and its success assessed. The study included longitudinal quantitative and qualitative surveys, and the analysis of those results is also examined. The chapter concludes with an evaluation of the overall impact of the project and the author’s role in it.
Active-Passive Dynamic Consensus Filters for Linear Time-Invariant Multiagent Systems

Active-passive dynamic consensus filters consist of a group of agents, where a subset of these agents are able to observe a quantity of interest (i.e. active agents) and the rest are subject to no observations (i.e. passive agents). Specifically, the objective of these filters is that the states of all agents are required to converge to the weighted average of the set of observations sensed by the active agents. Existing active-passive dynamic consensus filters in the classical sense assume that all agents can be modeled as having single integrator dynamics, which may not always hold in practice. Motivating from this standpoint, the contribution of this paper is to introduce a new class of active-passive dynamic consensus filters, where agents have (homogeneous) linear time-invariant dynamics. We demonstrate that for output controllable agents, the output of all active and passive agents converge to a neighborhood of the weighted average of the set of applied exogenous inputs. A numerical example is also given to illustrate the efficacy of the presented theoretical results.
Machiavelli Preferences Without Blame: Delegating Selfish vs. Generous Decisions in Dictator Games

Abstract Does the impulse to delegate a decision only arise when delegation mimics a selfish decision vs. a generous one? We address this question using a dictator experiment with two possible payment allocations and an option to delegate the payment decision to another player. Two delegation treatments are considered, one in which the delegation option is payoff-equivalent to a direct choice of a “selfish” allocation (better for the dictator, worse for the receiver) and another where it is equivalent to the direct choice of generous / equal payments. Dictators exhibit a significantly greater propensity to delegate in the selfish delegation treatment than in the generous delegation treatment. Results are consistent with “Machiavelli preferences” that only favor delegation when it promotes self-interested / other-harming outcomes.
Impacts of Alternative Emissions Allowance Allocation Methods under a Federal Cap-and-Trade Program

Abstract This paper examines the implications of alternative allowance allocation designs for industry profits and GDP under a federal cap-and-trade program to reduce greenhouse gas emissions. We employ a general equilibrium model of the U.S. economy with a unique treatment of capital dynamics that permits close attention to profit impacts. Effects on profits depend critically on the relative reliance on auctioning or free allocation of allowances. Freely allocating fewer than 15% of the emissions allowances generally suffices to prevent profit losses in the most vulnerable U.S. industries. Freely allocating all of the allowances substantially overcompensates these industries. When emissions allowances are auctioned and the proceeds employed to finance cuts in income tax rates, GDP costs are about 33% lower than when all allowances are freely allocated. Our results are robust to policies differing in stringency, the availability of offsets, and the opportunities for intertermporal trading of allowances.
Telenutrition for Inflammatory Bowel Disease: A Tipping Point for Dietary Wellness

Inflammatory bowel disease (IBD), Crohn's disease and ulcerative colitis, cause inflammation of the digestive tract. It is estimated that about three million Americans and, globally, over six million individuals, suffer from IBD. While most physicians, especially gastroenterologists, are experts in the function and pathology of the gastrointestinal tract, factors such as nutrition science education and training, bandwidth, culture, language, and the longitudinal nature of dietary care, represent some of the barriers to receiving optimal nutritional guidance. Remote dietary expert counseling, an emerging solution that has been further highlighted by the COVID-19 pandemic, can improve IBD patients' nutritional status, avoid food triggers, and reduce the frequency and severity of exacerbations.
A Nonprofit's Transition to Teletherapy Due to the COVID-19 Crisis: Learning How to Adapt

Due to the state of the COVID-19 in Florida, a community-based agency serving children and families had to transition abruptly to teletherapy. This agency adapted to pandemic-related challenges by transitioning from in-person to virtual therapy, which played a key role in safely serving community members. This article explores the unique benefits and difficulties of the transition to teletherapy under those circumstances. The agency clinical staff utilized their brief therapy skills and strengths-oriented perspective to aid in this abrupt transition, as illustrated by a case study. Ultimately, the agency's transition was a successful one as evidenced by a survey of both agency clinicians and clients, and by uninterrupted services at the same volume of cases and level of care. Suggestions are made for other providers seeking to cope with similar transitions.
High-quality-factor Fano resonances in monolayer WS2 coupled with a single dielectric nanosphere at room temperature

Great efforts have been made to explore the Fano resonances in two-dimensional transition metal dichalcogenides (TMDs) coupled with plasmonic nanostructures in the visible region. However, the intrinsic losses of metallic materials and the TMD exciton linewidths of at least tens of meV at room temperature (RT) inevitably limit the achievable Q factor of the Fano resonance. Herein, we integrate a monolayer WS2 with single hydrogenated amorphous silicon nanospheres (SiNSs) in water. Pronounced asymmetric Fano resonances with a Q factor up to 104 at the A exciton frequency (2.0 eV) are observed at RT. Fano fitting and modified coupled-mode theory both suggest a decreased A exciton linewidth of ~10 meV as compared to the reported value (~60 meV). This is attributed to the enhanced decay of trion in WS2. Moreover, directional Fano coupling can be achieved by exciting the hybrid from the SiNS or WS2 side, providing more possibilities in device implementation.
Comparison of Different Variants of the U.S. Army Occupational Physical Assessment Test

INTRODUCTION The U.S. Army Occupational Physical Assessment Test (OPAT) is a pre-enlistment physical employment screening assessment developed to place recruits and soldiers into Military Occupational Specialties (MOSs) based on their physical capabilities in order to optimize performance and limit injury. The OPAT consists of the seated power throw (SPT), strength deadlift (SDL), standing long jump, and interval aerobic run. During the scientific validation of the OPAT, two variants of the SPT and two variants of the SDL were used. Although the OPAT was validated using both variants for each test, U.S. Army scientists and policymakers have received queries regarding how these variants compare to each other. Therefore, the purpose of this study was to compare different variants of the SPT and SDL. MATERIALS AND METHODS Thirty-two participants (14 male and 18 female) between the ages of 18 and 42 years visited the laboratory on one occasion and performed two variants of the SPT (seated on the ground [the current OPAT standard] versus seated in a chair with a 35 cm seat height) and two variants of the SDL (using a hex-bar [the current OPAT standard] versus using paired dumbbells). Testing order for the different variants was randomized. The protocol was approved by the U.S. Army Medical Research and Development Command Institutional Review Board. RESULTS Performing the SPT from a chair significantly (P < .05) increased performance when compared to performing the SPT from the ground (5.4 ± 1.3 m versus 5.0 ± 1.4 m, respectively). Values for the two SPT variants were correlated (tau = 0.90). Performing the SDL using the hex-bar significantly increased the maximal weight lifted when compared to performing the SDL using paired dumbbells (86.9 ± 18.4 kg versus 83.1 ± 18.0 kg, respectively). Values for the two SDL variants were correlated (tau = 0.83). CONCLUSIONS Performing different variants of the SPT and SDL influenced the resulting score. Although these findings do not alter the administration or scoring of the OPAT, they do provide a valuable reference in the event of future inquiries regarding the development of the OPAT.
Fragment A of diphtheria toxin causes pH-dependent lesions in model membranes

Abstract Fragment A of diphtheria toxin has been shown to insert into lipid bilayers at low pH (Montecucco, C., Schiavo, G., and Tomasi, M. (1985) Biochem. J. 231, 123-128; Zhao, J.-M., and London, E. (1988) J. Biol. Chem. 263, 15369-15377). In this report, evidence is provided which demonstrates that fragment A, like diphtheria toxin, can also cause the release of a fluorescent dye (calcein) from vesicles under acidic conditions and that this release parallels fragment A insertion into the membrane. Although the permeability changes are not as large as those obtained with whole toxin (Jiang, G.-S., Solow, R., and Hu, V. W. (1989) J. Biol. Chem. 264, 13424-13429), molecular sieving experiments indicate that the lesion induced by fragment A increases in size with decreasing pH and reaches an upper limit of 30 A at pH 4.0. In addition to size differences, the lesion induced by fragment A releases calcein in a graded manner, whereas diphtheria toxin causes an all-or-none release. One possible interpretation of this result is that the fragment A lesion is transient in comparison to that induced by whole toxin. Although the molecular bases for the observed differences are not understood, these data suggest that fragment A interaction with the lipid bilayer may play a significant role in mediating its own translocation across membranes and that fragment B may aid this process by initiating, enlarging, and stabilizing the lesion formed.
Protection against neurodegeneration with low-dose methylene blue and near-infrared light.

Neurons are metabolically protected against degeneration using low-level methylene blue and near-infrared light interventions. Both of these novel interventions act by a cellular mechanism involving enhancement of the electron transport chain in mitochondria, which promotes energy metabolism and neuronal survival (Gonzalez-Lima et al., 2014). Methylene blue preferentially enters neuronal mitochondria after systemic administration, and at low-doses forms an electron cycling redox complex that donates electrons to the mitochondrial electron transport chain. Low-level near-infrared light applied transcranially delivers photons to cortical neurons that are accepted by cytochrome oxidase, which causes increased cell respiration and cerebral blood flow. Breakthrough in vivo studies with these interventions suggest that targeting mitochondrial respiration may be beneficial for protection against different types of neurodegenerative disorders. The purpose of this paper is to provide an update on the cellular mechanisms mediating the neuroprotective effects of low doses of methylene blue and near-infrared light, and to argue that the neurotherapeutic benefits of these two different interventions share the same cellular mechanism of action based on stimulation of mitochondrial respiration. Presented first is the explanation of the biochemical redox action of low-dose methylene as an electron cycler on the mitochondrial electron transport. Presented second is the explanation of the biophysical action of near-infrared light as a photon donor to cytochrome oxidase that also serves to stimulate mitochondrial electron transport. We finish with a comparison of these two interventions and how they share a common cellular mechanism with similar properties such as energy transfer, low-dose hormetic dose-responses, and enhanced capacity for oxidative metabolic energy production, which serve to protect nervous tissue from degeneration.
The Requirement for Membrane Sialic Acid in the Stimulation of Phagocytosis by the Natural Tetrapeptide, Tuftsin

Abstract The presence of sialic acid on the polymorphonuclear (PMN) phagocyte is necessary for maximal stimulation of its phagocytic activity by the tetrapeptide, tuftsin, Thr-Lys-Pro-Arg. Treatment of polymorphonuclear cells with bacterial neuraminidases, purified by affinity chromatography, completely abolishes stimulation of phagocytic activity by free tuftsin or by tuftsin bound to the carrier leukokinin molecule. These enzymes cleave sialic acid at both 2-3' and 2-6' glycosidic bonds. By contrast, treatment of cells with influenza virus neuraminidase, which cleaves predominantly the 2-3' linkage, reduces the tuftsin effect by approximately 50%. Enzyme-treated cells remain viable and capable of phagocytosis. Cells treated with any of the neuraminidases and cells of the untreated controls show comparable levels of phagocytosis in the absence of tuftsin. While membrane sialic acid is necessary for stimulation of phagocytosis, it may function only as a binding site for the three positively charged residues of the tetrapeptide. Neuraminidases from Vibrio cholerae or Clostridium perfringens, in excess amounts, released in 2 hours a maximum of about 135 million molecules of sialic acid per polymorphonuclear cell. Under similar conditions, treatment with influenza virus released approximately 30 million molecules per cell.
FNA, core biopsy, or both for the diagnosis of lung carcinoma: Obtaining sufficient tissue for a specific diagnosis and molecular testing

BACKGROUND Increasingly, minimally invasive procedures are performed to assess lung lesions and stage lung carcinomas. In cases of advanced-stage lung cancer, the biopsy may provide the only diagnostic tissue. The aim of this study was to determine which method—fine-needle aspiration (FNA), core biopsy (CBx), or both (B)—is optimal for providing sufficient tissue for rendering a specific diagnosis and pursuing molecular studies for guiding tumor-specific treatment. METHODS A search was performed for computed tomography–guided lung FNA, CBx, or B cases with rapid onsite evaluation. Carcinomas were assessed for the adequacy to render a specific diagnosis; this was defined as enough refinement to subtype a primary carcinoma or to assess a metastatic origin morphologically and/or immunohistochemically. In cases of primary lung adenocarcinoma, the capability of each modality to yield sufficient tissue for molecular studies (epidermal growth factor receptor, KRAS, or anaplastic lymphoma kinase) was also assessed. RESULTS There were 210 cases, and 134 represented neoplasms, including 115 carcinomas. For carcinomas, a specific diagnosis was reached in 89% of FNA cases (33 of 37), 98% of CBx cases (43 of 44), and 100% of B cases (34 of 34). For primary lung adenocarcinomas, adequate tissue remained to perform molecular studies in 94% of FNA cases (16 of 17), 100% of CBx cases (19 of 19), and 86% of B cases (19 of 22). No statistical difference was found among the modalities for either reaching a specific diagnosis (p = .07, Fisher exact test) or providing sufficient tissue for molecular studies (p = .30, Fisher exact test). CONCLUSIONS The results suggest that FNA, CBx, and B are comparable for arriving at a specific diagnosis and having sufficient tissue for molecular studies: they specifically attained the diagnostic and prognostic goals of minimally invasive procedures for lung carcinoma. Cancer (Cancer Cytopathol) 2015;123:318–26. © 2015 American Cancer Society.
Adversary Lower Bound for the Orthogonal Array Problem

We prove a quantum query lower bound \Omega(n^{(d+1)/(d+2)}) for the problem of deciding whether an input string of size n contains a k-tuple which belongs to a fixed orthogonal array on k factors of strength d<=k-1 and index 1, provided that the alphabet size is sufficiently large. Our lower bound is tight when d=k-1. The orthogonal array problem includes the following problems as special cases: k-sum problem with d=k-1, k-distinctness problem with d=1, k-pattern problem with d=0, (d-1)-degree problem with 1<=d<=k-1, unordered search with d=0 and k=1, and graph collision with d=0 and k=2.
Patterns and Processes of Salt Efflorescences in the McMurdo region, Antarctica

Abstract Evaporite salts are abundant around the McMurdo region, Antarctica (∼78°S) due to very low precipitation, low relative humidity, and limited overland flow. Hygroscopic salts in the McMurdo Dry Valleys (MDVs) are preferentially formed in locations where liquid water is present in the austral summer, including along ephemeral streams, ice-covered lake boundaries, or shallow groundwater tracks. In this study, we collected salts from the Miers, Garwood, and Taylor Valleys on the Antarctic continent, as well as around McMurdo Station on Ross Island in close proximity to water sources with the goal of understanding salt geochemistry in relationship to the hydrology of the area. Halite is ubiquitous; sodium is the major cation (ranging from 70%–90% of cations by meq kg-1 sediment) and chloride is the major anion (>50%) in nearly all samples. However, a wide variety of salt phases and morphologies are tentatively identified through scanning electron microscopy (SEM) and X-ray diffraction (XRD) work. We p...
Experimental and Analytical Study of Flow Diversion Beyond an Underexpanded Nozzle

A steady-state flow apparatus was used to investigate the process of gun gas diversion through a single hole perforated disk diverter. The amount of diverted flow was found to depend on the distance between the nozzle and the diverter disk and the ratio of nozzle pressure to diverter exit pressure. Experimental studies used nitrogen and carbon dioxide as the working fluids to show the effect of specific heat ratio.
Antibody production to the nucleocapsid and envelope of the hepatitis B virus primed by a single synthetic T cell site

The nucleocapsid (HBcAg) of the hepatitis B virus (HBV) can induce antibody responses via both a T-cell dependent and a T-cell independent pathway1 and is highly immunogenic during infection. We have examined the T-cell determinants of the antigen and find that HBcAg-specific helper T cells (TH) can help B cells produce antibody against envelope (HBsAg) antigens as well as HBcAg, even though these antigens are found on separate molecules. We have also been able to prime helper T cells with synthetic T-cell epitopes of HBcAg; helper cells primed with a single synthetic epitope can induce B cells to produce antibody that reacts with multiple HBsAg epitopes. One problem with the development of an HBV vaccine is that some vaccinees and patients do not respond to HBsAg directly; our results indicate that this problem can be circumvented using the response to HBcAg.
Effects of anesthesia and cranial electrode implantation on seizure susceptibility in the cat.

Abstract This study investigated the effects of routine “chronic preparation” surgical procedures on seizure susceptibility in adult cats. Susceptibility was measured as the latency to generalized tonic-clonic seizures after administration of monomethylhydrazine, a convulsive derivative of hydrazine. Two groups of unoperated control animals were compared with four experimental groups which were manipulated as follows: (i) anesthetic dose of barbiturate only; (ii) anesthetic agent plus one set of nonpenetrating, indwelling cortical electrodes; (iii) anesthetic agent plus two sets of cortical electrodes; or (iv) anesthetic agent plus multiple cortical and subcortical electrodes. The data from unoperated groups indicated remarkable stability in seizure response characteristics, clearly uninfluenced by gender, weight, time of year, or replication variables. Susceptibility to seizures was increased significantly in animals with cortical and subcortical electrodes, whose latencies were below the lower range of unoperated animals. This dichotomy was used to classify seizure response for evaluation of the other groups. Anesthesia alone produced a significant redistribution of seizure responses to shorter latencies. Anesthesia plus cortical electrodes produced further, progressive increases in susceptibility which were related to the number of electrode sets. The changes observed were not related exclusively to tissue damage from electrode penetrations, as suggested by other studies of surgical consequences, because both anesthesia alone and nonpenetrating electrodes were effective. Instead, effects were attributed to diffuse tissue damage. Accordingly, we suggest that susceptibility in this case varied directly with abnormality, regardless of its source or topography.
Isolation of polyadenylic acid-containing RNA using Ca(II).

Abstract Purine ribonucleotide homopolymers are insoluble in dilute Ca(II)- or Mg(II)-containing solutions whereas nucleic acid heteropolymers are soluble. The differences in solubility serve as a basis of a new method for separating polyadenylic acid-containing RNA from other nucleic acids. In the presence of as little as 10 mM Ca(II) polyadenylic acid-containing RNA of nucleic acid mixtures selectively coprecipitates with a small amount of added synthetic polyadenylic acid.
Necessary conditions for exponential stabilizability of distributed parameter systems with infinite dimensional unbounded feedback

Abstract In this paper we consider distributed parameter control systems of the form x′(t) = Ax(t) + Bu(t) , where x(t) is in the state space X, u(t) is in an infinite dimensional control space U , and B is an unbounded input operator which is admissible in a standard sense. We find necessary conditions for there to exist a compact operator K : X → U such that A + BK generates a C 0 - semigroup which is of exponential growth type μ. In particular, for every γ > μ , A must have at most finitely many eigenvalues of finite multiplicity in { Re (z) ≥ γ} . Furthermore, the part of A corresponding to the remaining spectrum must generate a semigroup with type at most γ. We apply this to a model for a clamped Euler-Bernoulli plate with Dirichlet control applied to the entire boundary. We show that a compact state feedback cannot exponentially stabilize the plate in the state space of maximum regularity.
Decision-theoretic image retrieval

The design of an effective architecture for image retrieval requires careful consideration of the interplay between the three major components of a retrieval system: feature transformation, feature representation, and similarity function. We present a review of ongoing work on a decision theoretic formulation of the retrieval problem that enables the design of systems where all components are optimized with respect to the same end-to-end performance criteria: the minimization of the probability of retrieval error. In addition to some previously published results on the theoretical characterization of the impact of the feature transformation and representation in the probability of error, we present an efficient algorithm for optimal feature selection. Experimental results show that decision-theoretic retrieval performs well on color, texture, and generic image databases in terms of both retrieval accuracy and perceptual relevance of similarity judgments.© (2002) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
An empirical study of a new method for forming group judgments: Qualitative Controlled Feedback

Abstract The Qualitative Controlled Feedback (QCF) method was developed by Press [1] to assist policy makers in forming judgments and making decisions that reflect the careful interactive reasoning and arguments of all of the members of a group or population. Since the QCF method involves controlled feedback, it tends to minimize the effects of face-to-face group interaction pressures. Since the feedback is “qualitative,” however, the procedure tends not to artificially induce a consensus on the group. This paper summarizes a feasibility study of the procedure. A sample of 111 faculty and staff members of the University of British Columbia participated in the testing of the method. The participants were asked to make a judgment on the importance of building an aquatic center on campus. A second (control) group of 89 faculty and staff members was surveyed on the same issue, but using the conventional survey method, that is, no feedback. It was observed that Qualitative Controlled Feedback created a good interaction (in the sense of exchanging arguments and reasons) among group members. Changes in judgments occurred as subjects went from one stage to another after having qualitative feedback of information. It was also found that the judgments given by the subjects in the qualitative controlled feedback group were distributed quite differently from those given by the control group. The method suggests a significantly new way of collecting and interpreting group judgments.
Novel Polyethylenimine-Modified Mesoporous Molecular Sieve of MCM-41 Type as High-Capacity Adsorbent for CO2 Capture

The objective of the work presented here is to develop a nanoporous solid adsorbent which can serve as a “molecular basket” for CO2 in the condensed form. Polyethylenimine (PEI)-modified mesoporous molecular sieve of MCM-41 type (MCM-41-PEI) has been prepared and tested as a CO2 adsorbent. The physical properties of the adsorbents were characterized by X-ray powder diffraction (XRD), N2 adsorption/desorption, and thermogravimetric analysis (TGA). The characterizations indicated that the structure of the MCM-41 was preserved after loading the PEI, and the PEI was uniformly dispersed into the channels of the molecular sieve. The CO2 adsorption/desorption performance was tested in a flow system using a microbalance to track the weight change. The mesoporous molecular sieve had a synergetic effect on the adsorption of CO2 by PEI. A CO2 adsorption capacity as high as 215 mg-CO2/g-PEI was obtained with MCM-41-PEI-50 at 75 °C, which is 24 times higher than that of the MCM-41 and is even 2 times that of the pure ...
Paediatric cardiac catheterization: innovations

In recent years interventional procedures have been introduced to the field of paediatric cardiac catheterization. These procedures continue to develop in complexity and increasingly are being applied to patients with reduced cardiovascular reserve, as an alternative to cardiac surgery or when cardiac surgery with cardiopulmonary bypass is contraindicated. More frequently anaesthetists are being called upon to provide support in sedating, anaesthetizing or/and resuscitating these patients. The purpose of this review is to give a comprehensive update of the interventional procedures and to review the anaesthetic management techniques as they apply to the catheterization laboratory. We will discuss possible complications and management strategies from our own experience and the experience of others. We have observed that as more complicated procedures are performed the anaesthetist plays a pivotal role in the management of the patient from arrival to departure from the cardiac catheterization laboratory, and in preventing mortality and major morbidity. Although the economic consequences of interventional cardiological techniques remain unclear, the field continues to expand and more complex procedures are continually being introduced.
Picosecond Dynamics Of Solution Reactions

There is now a four order of magnitude time range (≈100 fs to 1 ns) over which molecular dynamic calculations can overlap short light pulse experimental measurements to probe the microscopic nature of chemical processes. In this paper we combine theoretical molecular dynamics calculations of picosecond transient spectra with experimental measurements of such spectra to probe the molecular dynamics of a chemical reaction in solution. The example illustrated is the photodissociation of Ι2 followed by solvent caging, radical recombination to form a new highly vibra-tionally excited Ι2 molecule, and the subsequent decay of this vibrational energy to the solvent. We suggest, as Nes-bitt and Hynes do also, that the lifetimes observed in Ι2 picosecond absorption experiments may not be due to gem-inate recombination times, but perhaps to the time necessary for the recombined Ι2 molecules to vibrationally decay to levels with high Franck-Condon factors for absorption.© (1982) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Cooperative cell interactions in pure and mixed culture

Abstract The population growth and cell morphology of mouse A9s and human foreskin fibroblasts (HFFs) were used to investigate cooperative cell interactions in pure and mixed culture. It was found that neither cell line employed the bacterial growth optimization strategy whereby the lag phase is used to build up stockpiles of materials which serve as bottlenecks to limit growth. Instead, a strategy is employed which requires colony formation and cooperative cell interaction. The behavior of cell growth rates as a function of population density and time after seeding is more complicated than generally appreciated. At sparse density, shortly after seeding, there is a period of growth rate acceleration which is dependent upon population density. As moderate densities are achieved, this acceleration ceases and the growth rate levels off at a high value. As the cultures approach confluency, contact inhibition of growth occurs, and the growth rate decelerates to a lower but non-zero value. During non-confluency the growth rate of cultures is inversely proportional to the percent of singlets (individual cells not in contact with other cells) within a population. Moreover, there is a hysteresis-like effect in that the growth properties of cells depend not only upon momentary conditions, but upon the prior history of cell interactions as well. These effects are not the result of medium conditioning. Instead, they appear to involve either direct cell contact or at least the very close proximity of cells. During non-confluency the growth kinetics of A9s and HFFs in mixed culture are independent of one another. At near confluency, the A9s unilaterally inhibit further HFF proliferation, but themselves continue to reproduce past confluency by invading a second niche—the culture fluid overlying the mixed monolayer. Inhibition of HFF growth by A9s involves territorial exclusion, whereby HFFs are excluded from local areas heavily (but non-confluently) populated by A9s. Locally confluent domains of A9s expand by proliferation, and apparently cause nearby HFFs to retreat before them. As this encroachment progresses, HFFs seem to be herded together by the A9s into ribbon-shaped enclaves which cease proliferation but pile up into multi-layers.
Trypanosoma lewisi: termination of pregnancy in the infected rat.

Abstract Trypanosoma lewisi has previously been described as a nonpathogenic parasite of the rat, but these experiments demonstrate that both embryonal and maternal death may occur in the pregnant rat after infection with this parasite. Rats infected early in the first week of pregnancy resorbed their young with little apparent difficulty, and exhibited parasitemia curves typical of nonpregnant infected females of similar age. Rats infected late in the first week of pregnancy experienced greater difficulty resorbing the young, with half of the females dying shortly before parturition. The parasitemia counts were also similar to those of nonpregnant infected rats. The majority of rats infected during the midterm of pregnancy died at the time of parturition, without giving birth to their young. The number of parasites in these animals was abnormally high compared to nonpregnant infected females. Unusually large numbers of dividing trypanosomes were present in the placentae of these animals, many of them containing 8–16 nuclei and kinetoplasts. Animals infected during the last week of pregnancy gave birth to litters of normal size with little apparent difficulty, and had extremely low parasite counts. The hematocrits of all groups of infected animals showed a decrease at the time of peak parasitemia, and the hematocrits of all groups of pregnant rats showed a decrease at the time of birth, except for those infected when day 2 pregnant. These animals completely resorbed their young. The weight losses of rats infected on day 2 and day 6 of pregnancy reflected a termination of pregnancy.
Lacustrine varve formation through time

Abstract Studies using sediment traps in lakes reveal that the seasonal flux of sediment regulates both the composition and timing of deposition of materials that reach the bottoms of lakes. If the bottom waters of a lake are partly or totally anoxic, the seasonally deposited materials are preserved as annual groupings of laminae (varves). Common components that form individual laminae consist of allochthonous clastic material derived from the drainage basin, precipitated carbonate minerals, diatom frustules, iron-rich and manganese-rich flocs, autochthonous organic detritus, and autochthonous and allochthonous materials resuspended from the bottom. The “style” of varving has changed over geologic time, reflecting changes in biologic evolution and types of materials available. Precipitated iron-rich laminations were common in the middle Precambrian. Graded sets of clastic organic laminations persisted through the Precambrian, prior to the evolution of bioturbating benthic organisms. Glaciolacustrine varves appear to have retained their distinctive character through time. Carbonate-rich varves occurred sporadically in the Precambrian and Phanerozoic. With the exception of diatoms, major components of modern lacustrine varves were present through the Paleozoic and Mesozoic, and yet varves are rare in strata of these ages, and may have accumulated in marine to brackish-water environments. Diatoms were introduced into lacustrine systems in Early Tertiary time and are common components of varves from then on. Diatom laminae, combined with a greater chance for geologic preservation of younger lake deposits, have increased the number of geologically young occurrences of varved sediments. However, seasonal associations of modern varve components, and the processes they represent, are present in ancient deposits and provide clues to the interpretation of ancient environments.
Some Aspects of RNA Synthesis in Oyster Development

synopsis. Early development of the oyster embryo to the swimming stage (late blastula-early gastrula) is under control of information transcribed during oogenesis and stored in the egg. At the swimming stage, the nuclei become increasingly active in RNA synthesis and produce at least one new class of transcript. Transcription during this stage appears necessary for further development. This pattern of gene expression correlates with results found by others for the clams Spisula and Mulinia. The pattern of gene expression for bivalves is similar to that found for lower deuterostomes but is in contrast to various results from studies on different gastropods. There is evidently no general "spiralian" mode of gene expression during early development.
Understanding the INF debacle: Arms control and alliance cohesion

(1984). Understanding the INF debacle: Arms control and alliance cohesion. Arms Control: Vol. 5, No. 2, pp. 95-127.