cssi/SciSciGPT-SciSciNet huggingface dataset:
Poly(β-Amino Ester)-Nanoparticle Mediated Transfection of Retinal Pigment Epithelial Cells In Vitro and In Vivo

A variety of genetic diseases in the retina, including retinitis pigmentosa and leber congenital amaurosis, might be excellent targets for gene delivery as treatment. A major challenge in non-viral gene delivery remains finding a safe and effective delivery system. Poly(beta-amino ester)s (PBAEs) have shown great potential as gene delivery reagents because they are easily synthesized and they transfect a wide variety of cell types with high efficacy in vitro. We synthesized a combinatorial library of PBAEs and evaluated them for transfection efficacy and toxicity in retinal pigment epithelial (ARPE-19) cells to identify lead polymer structures and transfection formulations. Our optimal polymer (B5-S5-E7 at 60 w/w polymer∶DNA ratio) transfected ARPE-19 cells with 44±5% transfection efficacy, significantly higher than with optimized formulations of leading commercially available reagents Lipofectamine 2000 (26±7%) and X-tremeGENE HP DNA (22±6%); (p 0.05 for both). Our optimal polymer was also significantly better than a gold standard polymeric transfection reagent, branched 25 kDa polyethyleneimine (PEI), which achieved only 8±1% transfection efficacy with 25±6% cytotoxicity. Subretinal injections using lyophilized GFP-PBAE nanoparticles resulted in 1.1±1×103-fold and 1.5±0.7×103-fold increased GFP expression in the retinal pigment epithelium (RPE)/choroid and neural retina respectively, compared to injection of DNA alone (p = 0.003 for RPE/choroid, p<0.001 for neural retina). The successful transfection of the RPE in vivo suggests that these nanoparticles could be used to study a number of genetic diseases in the laboratory with the potential to treat debilitating eye diseases.
For theory and its others: Comment on Jay

I find Jay's discussion to be extremely useful. By identifying Theory's "others" both longstanding and new versions of Theory's alterities he elaborates clearly the various anti-theoreticist tendencies with which a Theory and Society community, or collegium, contends. With that elaboration, Jay can reconstruct the general ambition of a Reflexive Sociology or Critical Theory, moving it away from the grandiosity of Human Liberation toward a clarification of why Human Liberation is so hard to realize, and what more modest goals can take its place. This interest in dialogue is not so common, however.
Traumas and other adverse life events in adolescents with alcohol abuse and dependence.

Objective Clinical observation suggests that adolescents with alcohol use disorders often have complex histories that include childhood maltreatment and other traumas. The aim of this study was to determine the relationships among adolescent alcohol use disorders and a broad range of traumas and adverse life events. Method The subjects were 132 adolescents with alcohol dependence, 51 adolescents with alcohol abuse, and 73 adolescents recruited from the community as a control group. Trauma history was assessed by a semistructured interview and other adverse life events by questionnaire. Results Traumatic events reflecting interpersonal violence had occurred in many of the adolescents with alcohol dependence and abuse and few of the control adolescents. Adolescents with alcohol abuse or dependence, compared with control subjects, were 6 to 12 times more likely to have a physical abuse history and 18 to 21 times more likely to have a sexual abuse history. Sexual abuse was more common in females, and victimization by other violent acts was more common in males. Many other adverse life events were also significantly more common in the alcohol use disorder groups than in the control group, including having a close friend die, arguments within the family, and legal difficulties. Conclusions These results demonstrate that trauma and other adverse life events are strongly associated with alcohol use disorders in adolescents. Clinical screening of adolescents with alcohol use disorders for a range of traumatic events is recommended.
Evaluation of Hydrodynamic Size and Zeta-Potential of Surface-Modified Au Nanoparticle-DNA Conjugates via Ferguson Analysis

We evaluate Ferguson analysis as a method for simultaneously measuring the size and zeta-potential of gold nanoparticle-DNA (Au NP-DNA) conjugates. This approach is highly suitable when the particle size is <20 nm and biomolecular conformation results in a nonspherical or nonlinear conjugate, causing conventional dynamic light scattering and zeta-potential measurements to be unable to achieve consistent results. We show the applicability of the method by varying the size of gold nanoparticles (5–20 nm) and the loading of methoxypolyethylene glycol/DNA on particle surface and buffer concentrations. Due to the low ionic mobility of tris-borate-EDTA buffer (TBE) and relatively high zeta-potential of Au NP-DNA, Henry’s solutions with higher order correction terms are necessary for obtaining the zeta-potential from the measured free mobility and size.
Introduction to the special issue: Corporate communication: the way forward, on the occasion of CCI – Corporate Communication International's 10th anniversary

Purpose – The purpose of this paper is to discuss the future of corporate communication professionals and researchers; to present the findings of the Corporate Communication International (CCI) Corporate Communication Practices and Trends Study 2009; and to introduce the issues presented in the papers from the CCI Conference on Corporate Communication 2009 published in this special issue. Design/methodology/approach – The paper presents a discussion of the future of the corporate communication and the findings of the CCI Corporate Communication Practices and Trends Study 2009. Findings – The paper implies strategic knowledge of business processes and practice for effective corporate communication. Research limitations/implications – The paper implies several areas for further research. Originality/value – The paper articulates complex challenges facing corporate communicators.
Molecular basis for fibrillar aggregation of tropocollagen.

NO model for the three dimensional packing of tropocollagen (TC) molecules into fibrils1–3 approaches the problem on a molecular level; such analysis requires the assumption of a specific macromolecular structure4–6 and of a specific aggregation state7,8 of TC molecules. If the Ramachandran, Rich and Crick structure with the a1 chains in register from the N-terminus and the quarter stagger mode of association are assumed, then corresponding residues in the a chains will be separated by 108° radial angles4,6. Possible intermolecular associations, producing quarter-staggered7 TC aggregation, fall into two general classes: (1) association involving a single chain in one molecule with a single chain in another and (2) complex association loci involving more than one chain in each TC molecule. The former is the more likely possibility and would involve residues on an individual a chain, at intervals governed by the pitch of the super helix, forming a longitudinal edge which associates in a defined plane of contact with a complementary edge in a neighbouring TC molecule2,4,6.
Mass Psychogenic Illness, Trance States, and Suggestion

Abstract Reports of mass psychogenic illness (MPI) date to the thirteenth century in Europe. The historical and contemporary literature on mass psychogenic illness are reviewed and a case illustration is provided which meets the current diagnostic criteria for MPI. Speculation is offered about the similarities between mass psychogenic illness phenomena and “active-alert” trance states. In particular, the presence of a spontaneous trance state and heightened receptivity to suggestion leading to MPI are discussed.
Recent Developments in Delay Line Readout of Multiwire Proportional Chambers

The application of electromagnetic delay line readout methods for determining the track positions of ionizing particles in multiwire proportional chambers is described. Construction techniques for large area chambers, which allow the use of all three planes for track position measurements are given. The construction and characteristics of electromagnetic delay lines optimized for wire chamber readout are discussed.
A Strategy for Control of Imbalance Forces on the NASA Centrifuge Facility Project Mass Balance Testbed

A rationale and proposed strategy for control of forces resulting from unbalanced conditions on the NASA Cantrifuge Facility Project mass balance testbed is explained. The strategy is based upon a five rigid body state variable format model of the testbed. The motivation for the testbed study and the status of the realization of the algorithm for controlling the testbed hardware are described.
The microeconomics of food security

This article develops a dynamic microeconomic model of food security under uncertainty, with special focus on the relationships between food demand, nutrition and human survival. It investigates the influence of entitlements on malnutrition, hunger and starvation under uncertainty. It develops useful insights on the links between food security and a number of policy instruments commonly used in dealing with malnutrition and starvation.
The line shape of an inhomogeneously broadened resonance of large polyatomic molecules

Abstract The line shape of an inhomogeneously broadened resonance of large polyatomic molecules is expected to be asymmetric. Symmetry considerations - together with energy and intensity ones - determine whether the line will be symmetric or asymmetric.
Performance of class B audio amplifiers with random noise signals

During the past 3 years new problems in audio amplifier design have arisen as a result of using low-distortion high-power audio amplifiers for driving electrodynamic vibration exciters.1 Modern vibration testing procedures require that random noise forces be used to excite the test specimens. This requirement has arisen from efforts to reproduce the actual environments occurring in airborne guided missiles.2,3
Multi-way Semantic Specification of Domain-Specific Modeling Languages

Increased emphasis on the use of model-based design methods, particularly for developing Cyber-Physical Systems (CPS), has created challenges in the area of developing domain-specific modeling languages (DSML). To meet the increased demand for DSMLs, rapid development tools and techniques are needed. While tools such as the Generic Modeling Environment (GME) for the specification of the syntactic structure of DSMLs are well established, proper techniques for the specification of semantics and methods for integrating the semantic specifications with the language design tool suite remain interesting challenges. Current efforts in semantic specification of DSMLs focus solely on operational semantics. In this paper we show how the specification of multiple types of semantics can bring added benefit. We also emphasize the use of FORMULA, a formal modeling and analysis language, and show how it can be used to specify the semantics of a DSML in a way that integrates with DSML development tools. As a case study, we consider the operational and denotational semantics of a Statecharts-like language and show that the two semantic specifications can be used for complementary applications.
Use of biomolecular scaffolds for assembling multistep light harvesting and energy transfer devices

Abstract The development of biologically templated artificial light harvesting antennae and energy transfer devices is a highly active research area with exceptional challenges. Natural energy harvesting complexes have exquisite spectrally- and spatially-tuned systems with high redundancy to maximize their ability to gather, channel, and distribute electromagnetic radiation. Attempting to mimic these highly efficient systems requires at the very least (sub)nanoscale precision in the positioning of light sensitive molecules, the latter of which must also possess carefully selected photophysical properties; in essence, these two fundamental properties must be exploited in a synergistic manner. First, the scaffold must be highly organized, ideally with multiple symmetrical components that are spatially arranged with nanoscale accuracy. Second, the structure must be amenable to chemical modification in order to be (bio)functionalized with the desired light sensitive moieties which have expanded greatly to now include organic dyes, metal chelates, fluorescent proteins, dye-doped and noble metal nanoparticles, photoactive polymers, along with semiconductor quantum dots amongst others. Several families of biological scaffolding molecules offer strong potential to meet these stringent requirements. Recent advances in bionanotechnology have provided the ability to assemble diverse naturally derived scaffolds along with manipulating their properties and this is allowing us to understand the capabilities and limitations of such artificial light-harvesting antennae and devices. The range of scaffold or template materials that have been used varies from highly symmetrical virus capsids to self-assembled biomaterials including nucleic acids and small peptides as well as a range of hybrid inorganic–biological systems. This review surveys the burgeoning field of artificial light-harvesting and energy transfer complexes that utilize biological scaffolds from the perspective of what each has to offer for optimized energy transfer. We highlight each biological scaffold with prominent examples from the literature and discuss some of the benefits and liabilities of each approach. Cumulatively, the available data suggest that DNA is the most versatile biological material currently available, though it has challenges including precise dye placement and subsequent dye performance. We conclude by providing a perspective on how this field will progress in both the short and long term, with a focus on the transition to applications and devices.
Cytosolic protein‐protein interactions that regulate the amyloid precursor protein

Alzheimer disease (AD), a progressive neurodegenerative disease, is the most common cause of dementia in the elderly and is among the leading causes of death in adults. AD is characterized by two major pathological hallmarks, amyloid plaques and neurofibrillary tangles. For a number of reasons, amyloid plaque accumulation is widely thought to be the probable cause of AD. The amyloid plaque core is largely composed of an approximately 4-kDa peptide referred to as Ab .A b is derived from its precursor, the Alzheimer amyloid protein precursor (APP), by endoproteolytic processing. APP is a type I integral membrane protein, with a long extracellular domain, one transmembrane domain, and a short (E50 amino acid) cytoplasmic tail. Despite intense efforts to decipher the function of APP, its normal physiological role has remained elusive. The carboxy-terminus of APP contains the sequence YENPTY, which is absolutely conserved across APP homologues and across species. The YENPTY sequence is important for regulation of APP processing and trafficking. Given the importance of the cytoplasmic domain in APP physiology, a number of laboratories have hypothesized that proteins that bind to the YENPTY sequence in the cytoplasmic domain of APP might regulate APP processing, trafficking, and/or function. In this article, we will discuss data revealing which proteins bind to the cytoplasmic domain of APP, how these binding-proteins regulate APP metabolism and function, and why such protein-protein interactions provide an exciting new target for therapeutic intervention in AD. Drug Dev. Res. 56: 228-241, 2002. c 2002 Wiley-Liss, Inc.
Brown Recluse spider bite mediated hemolysis: clinical features, a possible role for complement inhibitor therapy, and reduced RBC surface glycophorin A as a potential biomarker of venom exposure.

Background The venom of Loxosceles reclusa (Brown Recluse spider) can cause a severe, life-threatening hemolysis in humans for which no therapy is currently available in the USA beyond supportive measures. Because this hemolysis is uncommon, relatively little is known about its clinical manifestation, diagnosis, or management. Here, we aimed to clarify the clinical details of envenomation, to determine the efficacy of the complement inhibitor eculizumab to prevent the hemolysis in vitro, and to investigate markers of exposure to Brown Recluse venom. Study Design and Methods We performed a 10-year chart review of cases of Brown Recluse spider bite-mediated hemolysis at our institution. We also designed an in vitro assay to test the efficacy of eculizumab to inhibit hemolysis of venom exposed red blood cells. Finally, we compared levels of CD55, CD59 and glycophorin A on venom exposed versus venom-naive cells. Results Most victims of severe Brown Recluse spider mediated hemolysis at our institution are children and follow an unpredictable clinical course. Brown Recluse spider bite mediated hemolysis is reduced by 79.2% (SD=18.8%) by eculizumab in vitro. Erythrocyte glycophorin A, but not CD55 or CD59, is reduced after red blood cells are incubated with venom in vitro. Conclusion Taken together, our laboratory data and clinical observations indicate that L. reclusa venom exposure results in non-specific antibody and complement fixation on red blood cells, resulting in complement mediated hemolysis that is curtailed by the complement inhibitor eculizumab in vitro. Glycophorin A measurement by flow cytometry may help to identify victims of L. reclusa envenomation.
Perception of inflections in brief visual presentations of words

An experiment was performed to investigate whether one aspect of syntax, verb inflection, creates units for perception in brief visual presentations of words and pseudowords. Inflections did tend to function as units, but not to increase the length of a word that could be read tachistoscopically. Priority of processing inflected endings occurred when the base was not a real word. It was concluded that words are read as complexes of features, of which syntax is one type, and that these features are processed independently.
Scanning force microscope study of detachment of nanometer adhering particulates

We employ salt particles deposited on soda lime glass substrates as a model system for particle detachment in chemically active environments. The chemical activity is provided by water vapor, and detachment is performed with the tip of a scanning force microscope. The lateral force required to detach nanometer-scale salt particles is a strong function of particle size and relative humidity. The peak lateral force at detachment divided by the nominal particle area yields an effective interfacial shear strength. The variation of shear strength with particle size and humidity is described in terms of chemically assisted crack growth along the salt/glass interface.
Site-Isolated Electro-optic Chromophores Based on Substituted 2,2'-Bis(3,4-propylenedioxythiophene) π-Conjugated Bridges

Application of bis(propylenedioxythiophene) (bis(ProDOT)) π-conjugated bridges bearing alkyl or aryl substituents in electro-optic (EO) chromophores is presented. A series of three bis(ProDOT)-based chromophores and a bithiophene-based control chromophore were prepared and fully characterized with regard to EO applications. The highly planar bis(ProDOT) bridge results in slightly larger (∼10%) molecular hyperpolarizability (β) values as compared to the bithiophene bridge, as measured by hyper-Rayleigh scattering at a variety of wavelengths. In amorphous polycarbonate guest–host films, however, the bulky substituents on the bis(ProDOT) bridge result in significantly larger (∼70%) poling-induced EO coefficient (r33) values, as measured by simple reflection ellipsometry at 1310 nm. This can be attributed to a roughly 2-fold enhancement in poling efficiency due to reduced intermolecular dipole–dipole interactions. This chromophore architecture also exhibits excellent temporal alignment stability and photochem...
Epicatechin regulation of mitochondrial structure and function is opioid receptor dependent.

Scope The flavanol (–)-epicatechin (Epi), a component of cacao, has cardiac protective benefits in humans. Our previous study demonstrated Epi has δ-opioid receptor (DOR) binding activity and promotes cardiac protection. Here we examined the effects of 10 days of Epi treatment on: cardiac mitochondrial respiration, reactive oxygen species production, calcium swelling, and mitochondrial membrane fluidity. Methods and results Mice were randomized into four groups: (i) control (saline), (ii) naltrindole (Nalt; DOR antagonist), (iii) Epi, and (iv) Epi + Nalt and received 1 mg/kg Epi or water via oral gavage. Nalt groups received 5 mg/kg ip per day for 10 days. Significant increases in mitochondrial respiration and enhanced free radical production during state 3 respiration were observed with Epi. Additionally, we observed significant increases in rigidity of mitochondrial membranes and resistance to calcium-induced mitochondrial swelling with Epi treatment. Blocking the DOR with Nalt resulted in decreases in all of the observed parameters by Epi treatment. Conclusion These findings indicate that Epi induces an integrated response that includes metabolic and structural changes in cardiac mitochondria resulting in greater functional capacity via DOR. Mitochondrial targeted effects of epicatechin may explain the physiologic benefit observed on cardiac protection and support epicatechin's potential clinical application as a cardiac protective mimetic.
A parallel approach for improving Geo-SPARQL query performance

Geospatial Semantic Web promises better retrieval geospatial information for Digital Earth systems by explicitly representing the semantics of data through ontologies. It also promotes sharing and reuse of geospatial data by encoding it in Semantic Web languages, such as RDF, to form geospatial knowledge base. For many applications, rapid retrieval of spatial data from the knowledge base is critical. However, spatial data retrieval using the standard Semantic Web query language – Geo-SPARQL – can be very inefficient because the data in the knowledge base are no longer indexed to support efficient spatial queries. While recent research has been devoted to improving query performance on general knowledge base, it is still challenging to support efficient query of the spatial data with complex topological relationships. This research introduces a query strategy to improve the query performance of geospatial knowledge base by creating spatial indexing on-the-fly to prune the search space for spatial queries a...
Radiation exposure from cervical spine radiographs.

Abstract Radiation exposure to hospital personnel during 41 cervical spine radio-graphs of 30 multiply injured patients was prospectively evaluated. A digital dosimeter was attached to the exposed torso of personnel applying upper extremity traction or managing the airway. Radiation exposure was measured during each radiograph. Any exposure of one or more milliroentgen was detectable. No radiograph resulted in a measurable radiation exposure. Multiple radiographs (up to five exposures) also did not register even the minimum recordable exposure, demonstrating that exposure is less than 1.0 mR per radiograph (P
Rule-based price fairness and its effect on willingness to purchase

Abstract This research tests the effect of rule-based price fairness (as opposed to fairness in the sense of “cheap”). In the first study, perceived rule-based price fairness is shown to influence the inferred fairness of the seller's pricing process which affects buyers' attitude toward the seller and willingness to purchase. In the second study, consumers are provided information as to whether the seller has followed a rule-based pricing process. The results indicate that the knowledge of how a price has been determined has a significant effect on how the price is perceived. The conclusion is that not just the price tag itself but how that price has been determined affects consumers' perceptions of fairness and willingness to purchase.
Spectroscopic studies of YO and YOYO fluorescent dyes in a thrombin‐binding DNA ligand

The fluorescent, oxazole yellow dye YO-Pro-1 iodide (YO) and its homodimer YOYO-1 iodide (YOYO) were studied in a thrombin-binding DNA ligand, or aptamer, (tb-ligand) and in an oligomer with the same base composition in a scrambled sequence (s-ligand), both single strands of 15 bases in length. Binding constants for the dye-ligand complexes, assuming 1:1 stoichiometry, were determined to be on the order of 107M−1 for YOYO and 105M−1 for YO, which are approximately 105 smaller than estimated constants for YOYO in double-stranded DNA. In both ligands, YOYO assumes a folded conformation that promotes stability of the dye-ligand complex and excitonic coupling between the two YO groups. The folded conformation provides greater overlap of the YO groups than has been reported for YOYO in double-stranded DNA; the overlap is slightly greater in tb-ligand than in s-ligand. Both dyes exhibit bi-exponential fluorescence decay in the ligands and the lifetimes of YOYO (3–4 ns and 7–8 ns) are longer and more discrete than those of YO (1–3 ns and 4–5 ns). Fluorescence anisotropy of YOYO is a low, constant value in both ligands due to intramolecular energy transfer between the overlapping YO groups. Higher anisotropies are observed for YO, and the value is slightly higher in s-ligand than in tb-ligand. The addition of thrombin to the s-ligand affects the fluorescence intensity and anisotropy of YO but not of YOYO. The absence of intermolecular G-quartet formation of the s-ligand was demonstrated. This suggests that thrombin interacts weakly with the s-ligand but is not sensed by the fluorescence of YOYO, which is dominated by the coupling between the YO groups in the folded conformation of the bound dye. The results of these studies have implications for the application of these dyes for detection of single-stranded DNA ligands and their binding interactions. © 1996 John Wiley & Sons, Inc.
IS THERE A SIGNALING EFFECT OF UNDERWRITER REPUTATION

In this article we examine the effect of underwriter reputation on the abnormal return due to an announcement to issue seasoned new equity. After controlling for other factors that relate asymmetric information to abnormal returns, underwriter reputation still significantly reduces the magnitude of the negative announcement effect. We also develop a procedure to extract a signaling component from the measure of underwriter reputation. We show that the signaling component of underwriter reputation positively and significantly affects abnormal returns. This result supports the notion that issuing firms use underwriter reputation as an effective instrument to signal that their stocks are not overvalued. JEL classification: D82, G24, G30
Intellect in evolution

Evolution: Essays in Honour of John Maynard Smith. Edited by P.J. Greenwood, P.H. Harvey and M. Slatkin. Cambridge University Press: 1985. Pp.328. 30, 49.50.
Primary arteritis (periarteritis nodosa) among children

Summary Instances of periarteritis nodosa in children as reported in the literature are reviewed and reports of two additional cases are added. The clinical aspects of this symptom complex are summarized and discussed. The most common symptoms and signs were found to be: (1) fever, (2) leucocytosis, (3) abdominal and rheumatic pains, and (4) evidence of renal disease. In the two cases reported herein the disease processes present were in wholly different stages. In the first case the arteries were the seats of an acute suppurative process. In the second case definitely regressing lesions with proliferative changes were found. The diseases now classified as “periarteritis nodosa” probably are symptom complexes or syndromes referable to a variety of infectious agents.
Refractory properties of auditory brain-stem responses evoked by electrical stimulation of human cochlear nucleus: evidence of neural generators

In this study of electrically-evoked auditory brain-stem responses (EABRs) elicited by cochlear nucleus stimulation, 3 waves were identified after the initial wave that is directly initiated by the electric stimulus. Varying the rate of periodic stimulation or the interval between pairs of stimuli revealed that the shorter the latency of a wave, the faster it recovered from activation (i.e. shorter refractory period). The slow recovery of the third wave and an accompanying contribution to the second wave could be accounted for by postsynaptic generation in the two medial superior olivary nuclei (MSO); the faster recovery of another contribution to the second wave by generation in an axonal tract bending around the contralateral MSO; and the fastest recovery of the first wave by another axonal pathway having larger axons. Comparison with the relative latencies and spatial distribution of an acoustically-evoked auditory brain-stem response (AABR) indicated that the third wave corresponds to wave V, the second to wave IV (called IVb), and the first to a wave that precedes wave IV (called IVa). The anatomical interpretations for the two later waves of the EABR are consistent with most of the extant data on the neural generators of AABR waves IV and V. Thus, the present data and analysis strengthen the identification of the electrically evoked responses as EABRs and provide a firmer foundation for intra-operative EABR monitoring to assist auditory brain-stem implant placement.
Exploration of the Relevance of Anxiety Sensitivity among Adults Living with HIV/AIDS for Understanding Anxiety Vulnerability

This investigation explored facets of anxiety sensitivity (AS—social, physical and mental concerns) in regard to somatization, anxiety and depression symptoms among people with HIV/AIDS. Significant relations were found for AS-physical concerns and somatization symptoms (β = .52, p = .007) and AS-mental concerns and anxiety symptoms (β = .29, p < .05), controlling for negative affectivity, gender and shared variance with other AS subscales. Together, AS subscales were significantly related to depression symptoms (ΔR2 = .11; p = .006), but no one subscale was independently related. Findings are discussed in terms of examining AS in better understanding the HIV/AIDS—anxiety relation.
Dermal absorption of the antioxidant 4,4'-thiobis(6-tert-butyl-m-cresol) in Sencar mice and Fischer rats.

Abstract The dermal absorption of 14C-labeled 4,4'-thiobis(6-tert-butyl-m-cresol) (TBBC) was studied in female Sencar mice and male Fischer rats. Dermal application resulted in about 20% absorption in mice with more than 70% of the initial body burden (1BB) remaining on the treated skin site 3 days after treatment. In rats, less than 2% of a dermal dose was absorbed. This is in agreement with previous in vitro percutaneous absorption studies which have demonstrated that mouse skin is more permeable than rat skin to certain chemicals. Absorption did not increase linearly as the dose increased. Oral and i.v. exposures were conducted in the Sencar mice and compared to previously published rat oral and i.v. data. The disposition was similar between rats and mice after these routes of exposures, and the major route of elimination of absorbed TBBC was the feces in both species.
Microbial Degradation Of Normal Paraffin Hydrocarbons In Crude Oil

Abstract Experiments designed to measure the oxidation and degradation of crude oils by naturally occurring marine microorganisms are presently being conducted. Fifty active oil degrading cultures have been isolated in enriched seawater containing crude oil. Oil degradation has been determined with gas chromatography, wet combustion, and by measurement of surface tension. Normal paraffin hydrocarbons through C-26 are degraded by two different groups of micro organisms-those growing in the oil phase only and those growing in the aqueous phase. Emulsification of the crude oil through production of surfactants was observed in many of the enriched cultures. Microbial degradation of 35 to 55 per cent of oxidizable crude oil occurred within 60 hours.
Probability learning to avoid shock

Relatively little has been reported about the joint effects of magnitude and probability of shock on choice behavior. Cole, Belenky, Boucher, Fernandez, & Myers (1965) have given a brief review of findings where correction procedures were used. Cole et al found increasing overmatching of 11 = .667 with increasing shock intensity, also using a correction procedure. The present study was designed to study the effects of varying both probability and intensity of shock on choice behavior, using a non-correction procedure. It was expected that increasing both shock level and probability in one side would increase the probability of choosing the more frequently shock-free side. A second purpose was to see if a non-correction procedure would yield learning described by an identity operator model for the effect of nonreinforced trials (Weinstock, North, Brody, & LoGuidice, 1965). Method The Ss were 48 male, hooded rats, 90-120 days old. Beginning 10 days before the experiment, Ss were main­ tained on a 1/2 hr. per day feeding schedule, and handled by E for 5 min. each day. The Ss were about 20 hr. food deprived at the beginning of each session. The apparatus was a Y -maze made of galvanized steel. The stem was 6 in. long. The arms were 30 in. long and 3-1/2 in. wide, with floors having a downward angle toward the center with a 2/3 in. separation along their lengths, so that when the floor was charged it was impossible for S to avoid the shock. An Applegate generator supplied the shock. Each arm terminated in a goal box. Guillotine doors between the start box and stem, and between the stem and each arm, prevented retracing. Photocells located 8 in. inside each arm turned on the shock throughout the length of the arm. The only escape from shock was in the goal boxes, which were baited with four 97 mgNoyesfoodpellets on every trial. Since it was possible for S to avoid shock by not running, food deprivation and reward were used to insure running. Each S received 22 pre-experimental trials without shock: six forced-choice trials on days 1 and 2, with
The Production of Completion Signals by Asynchronous, Iterative Networks

In a synchronous circuit an operation is complete when a given number of clock times have elapsed since it was begun. In an asynchronous network no such indication is available, and we must either rely on the network to inform us of completion, or wait for the worst-case delay. The second method is undesirable because normally the network will complete its operation long before the worst-case delay time has elasped. It will be shown here that, for a large class of iterative circuits, the network can be designed to inform us of completion. Moreover, this can be done without recourse to monitoring all lateral states (to see when none are changing).
Interactions of pyrethroids with gramicidin-containing liposomal membranes.

Abstract Fluorescence steady-state anisotropy and phase-modulation lifetime techniques have been utilized to study the interactions of pyrethroid compounds with fluid-phase phosphatidylcholine membranes containing the polypeptide gramicidin. This polypeptide is considered to be a model of hydrophobic regions of cellular integral membrane proteins. The pyrethroids disorder lipid packing in cellular membranes and gel-phase liposomes but do not disorder lipid packing in fluid-phase lipid (Stelzer, K.J. and Gordon, M.A. (1984) J. Immunopharmacol. 6, 381–410 (1985) Biochim. Biophys. Acta 812, 361–368) Irrespective of liposomal size, gramicidin incorporation resulted in a substantial increase in anisotropy of the fluorescent probe, 1,6-diphenyl-1,3,5-hexatriene (DPH), in fluid phase lipid. In the absence of gramicidin, permethrin and three other pyrethroids, allethrin, cypermethrin and fenpropathrin, increased DPH anisotropy. In these fluid phase systems, as the protein:lipid ratio was increased, the extent of the pyrethroid-mediated increase in fluorescence anisotropy diminished. Also, the pyrethroids shortened DPH fluorescence lifetimes. At high gramicidin:lipid ratios, permethrin substantially lowered anisotropy in the fluid phase lipid, relative to controls. The data suggest that pyrethroids disturb fluid-phase lipids which have been promoted to a relative state of order by proximity to an integral membrane protein. This type of order is one which is represented by DPH fluorescence anisotropy. A model based on these results is proposed to explain the effects of pyrethroids on lipid packing order in cellular membranes, as determined by DPH fluorescence anisotropy.
Monkey models for brain-machine interfaces: The need for maintaining diversity

Brain-machine interfaces (BMIs) aim to help disabled patients by translating neural signals from the brain into control signals for guiding prosthetic arms, computer cursors, and other assistive devices. Animal models are central to the development of these systems and have helped enable the successful translation of the first generation of BMIs. As we move toward next-generation systems, we face the question of which animal models will aid broader patient populations and achieve even higher performance, robustness, and functionality. We review here four general types of rhesus monkey models employed in BMI research, and describe two additional, complementary models. Given the physiological diversity of neurological injury and disease, we suggest a need to maintain the current diversity of animal models and to explore additional alternatives, as each mimic different aspects of injury or disease.
Large-Signal Performance and Modeling of Intrinsically Switchable Ferroelectric FBARs

This paper presents the large-signal performance of intrinsically switchable ferroelectric thin-film bulk acoustic resonators (FBARs), as well as their modeling procedure. There has been a growing interest in ferroelectric FBARs due to their electric-field-dependent permittivity and electric-field-induced piezoelectricity. Ferroelectric barium-strontium-titanate (BaxSr(1-x)TiO3) FBARs are intrinsically switchable, namely, they have resonances that switch on with the application of a dc-bias voltage. In this paper, the large-signal performance and nonlinear behavior of ferroelectric BST FBARs are investigated. Measurement results show that the device nonlinearity can be reduced by applying higher dc-bias voltages. Moreover, a large-signal model that accurately describes the dc-bias voltage, as well as RF power-dependent performance of BST FBARs is developed. Large-signal simulation results obtained from this model at different bias voltages and RF power levels show good agreement with the measurement results.
Pediatric Ear, Nose, and Throat Emergencies

Acute otitis media is the most common infection for which antibiotics are prescribed in children, resulting in more than 20 million antibiotic prescriptions annually. New practice guidelines published by the American Academy of Pediatrics and the American Academy of Family Physicians call for the judicious use of antibiotics in view of increasing antibiotic resistance and the unclear necessity of the use of antibiotics in children with uncomplicated acute otitis media. This article reviews those guidelines, several other common ear, nose, and throat entities, including sinusitis and dental emergencies, and current strategies in diagnosis and treatment.
‘Substitutional alloys’ of organic polymeric conductors

Abstract Electrically conducting ‘copolymers’ of thiophene with pyrrole, N-methylpyrrole, and furan, whose conductivities vary as a function of (among other things) the heteroatom composition have been prepared. The use of a tri-ring monomer allows the production of these ‘substitutional alloys’ with a controlled heteroatom composition and formally known sequence distribution.
An Antibody Binding Site on Cytochrome c Defined by Hydrogen Exchange and Two-Dimensional NMR

The interaction of a protein antigen, horse cytochrome c (cyt c), with a monoclonal antibody has been studied by hydrogen-deuterium (H-D) exchange labeling and two-dimensional nuclear magnetic resonance (2D NMR) methods. The H-exchange rate of residues in three discontiguous regions of the cyt c polypeptide backbone was slowed by factors up to 340-fold in the antibody-antigen complex compared with free cyt c. The protected residues, 36 to 38, 59, 60, 64 to 67, 100, and 101, and their hydrogen-bond acceptors, are brought together in the three-dimensional structure to form a contiguous, largely exposed protein surface with an area of about 750 square angstroms. The interaction site determined in this way is consistent with prior epitope mapping studies and includes several residues that were not previously identified. The hydrogen exchange labeling approach can be used to map binding sites on small proteins in antibody-antigen complexes and may be applicable to protein-protein and protein-ligand interactions in general.
The importance of modality specificity in diagnosing central auditory processing disorder.

Purpose: This article argues for the use of modality specificity as a unifying framework by which to conceptualize and diagnose central auditory processing disorder (CAPD). The intent is to generat...
Efficient parallel receive beam forming for phased array imaging using phase rotation (medical US application)

A method for multiple beam formation in the near field using phase rotation (i.e., Fourier inversion) is presented. This method, if used in conjunction with a digital beamformer described by M. O'Donnell et al. (IEEE Ultrasonics Sym. Proc., vol.3, p.1499-1502, 1990), can produce multiple simultaneous beams of high precision with little increase in the complexity of the beamformer. This method combines dynamic focusing along a single beam with range-independent spatial Fourier processing to generate a set of high-quality simultaneous receive beams in the neighborhood of the dynamically focused beam. This system produces images of comparable quality to conventional beamformers but at twice the frame rate. >
Rheumatoid arthritis: A review of the cutaneous manifestations

Rheumatoid arthritis is a chronic inflammatory arthritis with significant extra-articular manifestations. Of note are unique cutaneous manifestations that the dermatologist may encounter. This article will make the dermatologist more cognizant of these skin findings in patients with this systemic inflammatory disorder. It examines rheumatoid arthritis, focusing on the general nonspecific and disease-specific rheumatoid arthritic skin changes. Classic rheumatoid nodules, accelerated rheumatoid nodulosis, rheumatoid nodulosis, rheumatoid vasculitis, Felty syndrome, pyoderma gangrenosum, interstitial granulomatosus dermatitis with arthritis, palisaded neutrophilic and granulomatosis dermatitis, rheumatoid neutrophilic dermatitis, juvenile rheumatoid arthritis, and adult-onset Still disease are reviewed. Understanding the cutaneous expressions of rheumatoid arthritis may lead to early diagnosis, prompt treatment, and lower morbidity and mortality for the affected persons. Learning objective At the completion of this learning activity, participants should be able to describe rheumatoid arthritis in terms of its epidemiology, etiology, pathogenesis, and general and specific cutaneous manifestations.
Practical Issues in Imputation-Based Association Mapping

Imputation-based association methods provide a powerful framework for testing untyped variants for association with phenotypes and for combining results from multiple studies that use different genotyping platforms. Here, we consider several issues that arise when applying these methods in practice, including: (i) factors affecting imputation accuracy, including choice of reference panel; (ii) the effects of imputation accuracy on power to detect associations; (iii) the relative merits of Bayesian and frequentist approaches to testing imputed genotypes for association with phenotype; and (iv) how to quickly and accurately compute Bayes factors for testing imputed SNPs. We find that imputation-based methods can be robust to imputation accuracy and can improve power to detect associations, even when average imputation accuracy is poor. We explain how ranking SNPs for association by a standard likelihood ratio test gives the same results as a Bayesian procedure that uses an unnatural prior assumption—specifically, that difficult-to-impute SNPs tend to have larger effects—and assess the power gained from using a Bayesian approach that does not make this assumption. Within the Bayesian framework, we find that good approximations to a full analysis can be achieved by simply replacing unknown genotypes with a point estimate—their posterior mean. This approximation considerably reduces computational expense compared with published sampling-based approaches, and the methods we present are practical on a genome-wide scale with very modest computational resources (e.g., a single desktop computer). The approximation also facilitates combining information across studies, using only summary data for each SNP. Methods discussed here are implemented in the software package BIMBAM, which is available from http://stephenslab.uchicago.edu/software.html.
Composition of pigmented centers of cholesterol gallstones

Most cholesterol gallstones have visually pigmented centers, but it is unclear whether this represents simple co-precipitation of pigment with cholesterol during stone nidation or nidation on a true pigment stone center. To clarify this issue, we selected from among 67 sets of cholesterol gallstones, 12 sets with the most conspicuously pigmented centers. The composition of the centers and the peripheries of these 12 stones was analyzed using infrared spectroscopy and compared with that of 10 black pigment gallstones. The pigmented centers of cholesterol stones contained 80.1 +/- 7.9% (mean +/- S.E.) cholesterol, 6.2 +/- 3.4% calcium bilirubinate (only 4 of the 12 centers had measurable calcium bilirubinate), trace amounts of calcium phosphate and no calcium carbonate or calcium palmitate. The peripheral areas of the cholesterol stones contained 91.6 +/- 2.3% cholesterol and no detectable calcium salts. For comparison, the composition of the centers of 10 black pigment gallstones was 13.5 +/- 2.2% cholesterol, 28.2 +/- 5.3% calcium bilirubinate, 5.5 +/- 2.4% calcium phosphate and 10.6 +/- 5.8% calcium carbonate. The composition of only one cholesterol stone center (15.8% cholesterol, 26.8% calcium bilirubinate) resembled that of a pigment stone, but even this center differed from that of a typical pigment stone in that it contained only a trace amount of calcium phosphate and no calcium carbonate. Thus, the chemical composition of pigmented centers of cholesterol gallstones is quantitatively different from that of black pigment stones, suggesting that cholesterol gallstones do not form on a pigment stone nidus.
Optimal liberalization of financial markets

Abstract As financial markets become completely liberalized, countries gain from improved risk sharing, but less wealthy countries can no longer profit from borrowing abroad at the lower rate and reinvesting at home at the higher rate. With decreasing rather than constant returns to capital, the gain from risk sharing is more likely to dominate the loss of the difference between the borrowing rate abroad and the decreasing reinvestment rate at home. Complete liberalization is likely to be optimal for less wealthy countries unless their labor endowment is large, their productivity is large, or holdings by foreigners are small, as in China.