cssi/SciSciGPT-SciSciNet huggingface dataset:
Membrane Requirement for Folding of the Herpes Simplex Virus 1 gB Cytodomain Suggests a Unique Mechanism of Fusion Regulation

Herpes simplex virus type 1 (HSV-1) enters cells by fusion of its envelope with a host cell membrane, which requires four viral glycoproteins and a cellular receptor. Viral fusion glycoprotein B (gB) mediates membrane fusion through the action of its ectodomain, while its cytoplasmic domain (cytodomain) regulates fusion from the opposite face of the membrane by an unknown mechanism. The gB cytodomain appears to restrict fusion, because point or truncation mutations within it increase the extent of fusion (syn mutations). Previously, we showed that the hyperfusion phenotype correlated with reduced membrane binding in gB syn truncation mutants and proposed that membrane binding was important in regulating fusion. Here, we extended our analysis to three syn point mutants: A855V, R858H, and A874P. These mutations produce local conformational changes, with some affecting membrane interaction, which suggests that while syn mutants may deregulate fusion by somewhat different mechanisms, maintaining the wild-type (WT) conformation is critical for fusion regulation. We further show that the presence of a membrane is necessary for the cytodomain to achieve its fully folded conformation and propose that the membrane-bound form of the cytodomain represents its native conformation. Taken together, our data suggest that the cytodomain of gB regulates fusion by a novel mechanism in which membrane interaction plays a key role.
Percutaneous Abdominal Abscess Drainage: A Historical Perspective

AJR:191, September 2008 introduced with a trocar technique after a positive preliminary aspiration. Given that this was early in their experience, the results were encouraging. Of nine attempted aspira­ tions using methods 1 and 2, eight were reported successful. Method 3 was attempted twice and was successful in one case. More im portant, there were no complications other than the aspiration failures. Haaga and colleagues [2] accurately concluded that CT is an excellent diagnostic and guidance tool for the percutaneous treatment of abdominal fluid collections. They recognized that CT, despite its ability to show gas and the extraluminal nature of the collection, is somewhat limited in its ability to fully characterize the fluid. Finally, they suggested that for definitive drainage the abscess must be superficial to avoid undesired peritoneal contamination and injury to adjacent structures. In short, the seed had been planted for percutaneous CT­ guided drainage procedures. Two years later, Gerzof and associates [3] reported their experience with percutaneous drainage procedures using both sonographic and CT guidance. In this study, they reviewed their experience in 23 patients in whom they used one of two drainage techniques: Seldinger (over guidewire)—with delivery of an 8­French angiographic pigtail catheter for drainage and trocar—with placement of 12­ or 16­French Argyle­Ingram catheters. They used sonographic guidance in 20 of 24 cases and CT guidance in the remaining four cases. The catheters were kept in place an average of 14 days in 22 patients, and only one patient required an open operation after failure of percutaneous drainage. Gerzof and associates [3] reported two major complications—one empyema and one hemorrhage—as well as three minor complications—chills, fever, and cutaneous sinus tract. Similar to the Haaga et al. [2] Percutaneous Abdominal Abscess Drainage: A Historical Perspective
QSAR studies for prediction of cross-β sheet aggregate binding affinity and selectivity

Protein aggregates that accumulate in neurodegenerative diseases are important targets of radiotracer discovery efforts. Although multiple scaffold classes have been reported to bind cross-beta sheet structure, their mechanism of binding and their ability to interact selectively with aggregates of varying protein composition are not well understood. Here we take a ligand-based quantitative structure activity relationship approach to identify descriptors of binding affinity and selectivity for a series of fifty closely related benzothiazole derivatives reported to displace Thioflavin T fluorescent probe from synthetic aggregates composed of beta-amyloid peptide and insulin. Using a two-step workflow involving both partial least squares and multiple linear regression methods, compound polarizability and hydrophobicity were identified as tunable mediators of binding selectivity. The correlations also revealed how polarizability could be modulated in neutral compounds having push-pull character. These data suggest that the relative affinity of small molecules for binding sites exposed on aggregate surfaces can be modulated by simple chemical design considerations that are compatible with multiple scaffolds.
In Vivo Phosphorylation of Partner Switching Regulators Correlates with Stress Transmission in the Environmental Signaling Pathway of Bacillus subtilis

Exposure of bacteria to diverse growth-limiting stresses induces the synthesis of a common set of proteins which provide broad protection against future, potentially lethal stresses. Among Bacillus subtilis and its relatives, this general stress response is controlled by the σ B transcription factor. Signals of environmental and energy stress activate σ B through a multicomponent network that functions via a partner switching mechanism, in which protein-protein interactions are governed by serine and threonine phosphorylation. Here, we tested a central prediction of the current model for the environmental signaling branch of this network. We used isoelectric focusing and immunoblotting experiments to determine the in vivo phosphorylation states of the RsbRA and RsbS regulators, which act in concert to negatively control the RsbU environmental signaling phosphatase. As predicted by the model, the ratio of the phosphorylated to unphosphorylated forms of both RsbRA and RsbS increased in response to salt or ethanol stress. However, these two regulators differed substantially with regard to the extent of their phosphorylation under both steady-state and stress conditions, with RsbRA always the more highly modified. Mutant analysis showed that the RsbT kinase, which is required for environmental signaling, was also required for the in vivo phosphorylation of RsbRA and RsbS. Moreover, the T171A alteration of RsbRA, which blocks environmental signaling, also blocked in vivo phosphorylation of RsbRA and impeded phosphorylation of RsbS. These in vivo results corroborate previous genetic analyses and link the phosphorylated forms of RsbRA and RsbS to the active transmission of environmental stress signals.
3D triangulation of a Sun-grazing comet

Abstract The bright Kreutz Comet C/2007 L3 (SOHO) entered the fields of view of the twin Solar Terrestrial Relations Observatory (STEREO) COR1 telescopes on 7–8 June 2007. The 12° separation between the two spacecraft at the time afforded the opportunity to derive the position of the comet's tail in three-dimensional space using direct triangulation. The track of the comet's orbit is compared against more traditional orbital calculations using observations from the STEREO COR2 telescopes, and from the Large Angle and Spectrometric Coronagraph (LASCO) aboard the Solar and Heliospheric Observatory (SOHO). The shape of the comet's tail shows that it is composed of dust particles released when the comet was between 18 and 22 solar radii, with no significant dust production after that. The comet did not survive perihelion passage, but a rare faint remnant of the comet tail persisted for several hours after the break-up, and was seen by both the SOHO and STEREO coronagraphs to drift slowly away from the Sun. This tail remnant was found to be composed of particles far back from the head of the comet. The motion of the tail remnant shows a loss of angular momentum during the passage through the solar corona. Atmospheric drag is estimated to account for a significant fraction of this change in angular momentum, but indications are that other mechanisms may be required to completely account for the total amount of change.
Impurities and conductivity control in Al-rich AlGaN alloys

AlGaN alloys are recognized as promising materials for applications in optoelectronic devices in deep ultraviolet (DUV) spectral range. Highly conductive (p- and n-type) AlGaN alloys are essential for device applications. Although n-type AlN has been reported by Si doping, further improvements in the material quality and conductivity are still needed for many device applications. One of the major difficulties in obtaining highly conductive n-type Al-rich AlGaN alloys is the generation of deep level defects that compensate free electrons. By employing DUV photoluminescence spectroscopy, we have identified three electron compensating centers — isolated cation-vacancy with three negative charges (V III )3−, cation-vacancy-complexes with two negative charges (V III -complex)2−, and cation-vacancy-complexes with one-negative charge, (V III -complex)−1. The energy levels of these three deep level centers in Al x Ga 1−x N (0 ≤ × ≤ 1) alloys are pinned to a common energy level in vacuum. It was observed that that suppressing the concentrations of these defects could significantly improve the conductivity and material quality of Al-rich AlGaN alloys and hence the performance of DUV LEDs. However, a far more serious issue for the realization of high performance DUV LEDs is the poor p-type conductivity of Al-rich Al x Ga 1−x N, which is inherent to AlGaN. This issue is caused by the large acceptor activation energies (Ea) of Al x Ga 1−x N (as large as ∼500 meV in AlN). Since the free hole concentration (p) depends exponentially on acceptor energy level, p∼exp(-EA/kT), an Ea value around 500 meV translates to only 1 free hole for roughly every 2 billion (2×109) incorporated Mg impurities (at 300 K). This causes an extremely low free hole injection efficiency into the quantum well (QW) active region and is a major obstacle for the realization of high performance AlGaN-based DUV LEDs. We report on the growth, doping and optical and transport properties of p-type layers optimized for DUV emitter structure incorporation. Benefits of using AlN epi-templates in DUV emitter structures will also be elaborated.
AN ECHOCARDIOGRAPHIC COMPOSITE CARDIAC CALCIFICATION SCORE PREDICTS MAJOR CARDIOVASCULAR EVENTS IN PATIENTS WITH STABLE CORONARY ARTERY DISEASE: THE HEART AND SOUL STUDY

Transthoracic echocardiography (TTE) enables detection of calcification in several discrete sites within the cardiovascular system. We have previously shown that mitral annular calcification and aortic valve sclerosis are independently associated with cardiovascular (CV) events in patients with
Great expectations: single mothers in higher education

This ethnographic study examines the educational experiences of 10 women who are both social service recipients and higher education students. Study participants view higher education in a variety of ways that include both instrumental and transformational purposes. By situating participants’ experiences in the larger economic and social context of welfare reform and shrinking employment opportunities, this paper provides a critical analysis of their assumptions concerning higher education.
Investigation of stress singularity fields and stress intensity factors for cracks [IC packages]

The reliability of semiconductor devices and packages used in microelectronics is compromised by interfacial delamination and homogenous cracking that is initiated at the edge of the interface between dissimilar materials during processing and stress tests. These failures have certain characteristics in that they begin at the stress singularity point. The knowledge of interfacial fracture mechanics is very important to the design for reliability of these devices and packages. In this paper, a model of stress singularity is proposed and applications of the model for the characterization of interfaces are subsequently presented. Examples are integrated circuit (IC) device interfaces and plastic package interfaces. These interfaces were mainly characterized with the order of stress singularity. Furthermore, this study demonstrates applications of the stress intensity factors for the stress singularity fields. The stress intensity factors were obtained from a r-/spl theta/ coordinate system, the order of stress singularity, the Dunders' parameters, and the extrapolation as a function of distance. The relationship between the stress intensity factors and the fracture toughness strength of molding compound as a function of mode mixity was also investigated for cracking at the edge of the interface. The proposed numerical scheme was verified by the experiments on the lead-on-chip (LOC) package crack under temperature cyclic loads.
Cloning of Tumor Suppressor Genes Involved in Solid Tumor Development

Objective: The homozygous inactivation of tumor suppressor genes is a common event in the multistep process of tumorigenesis. The identification of most tumor suppressor genes known to date has come from the study of individuals with a defective copy of such a gene that increases their predisposition to malignancy. Although much is still to be learned about the function of these genes, they all seem to play a role in cell growth regulation. Karyotypic and molecular studies of several solid tumors suggest the presence of at least three tumor suppressor genes on the short arm of human chromosome 3. We present an overview on the progress made in the identification of tumor suppressor genes involved in solid tumor development. Conclusion: The explosive effort to map the human genome fueled by the Human Genome Project will facilitate the identification of tumor suppressor genes on chromosome 3 and on other chromosomes within
Analysis of a consumer survey on plug-in hybrid electric vehicles

Abstract Plug-in Hybrid Electric Vehicles (PHEVs) show potential to reduce greenhouse gas (GHG) emissions, increase fuel efficiency, and offer driving ranges that are not limited by battery capacity. However, these benefits will not be realized if consumers do not adopt this new technology. Several agent-based models have been developed to model potential market penetration of PHEVs, but gaps in the available data limit the usefulness of these models. To address this, we administered a survey to 1000 stated US residents, using Amazon Mechanical Turk, to better understand factors influencing the potential for PHEV market penetration. Our analysis of the survey results reveals quantitative patterns and correlations that extend the existing literature. For example, respondents who felt most strongly about reducing US transportation energy consumption and cutting greenhouse gas emissions had, respectively, 71 and 44 times greater odds of saying they would consider purchasing a compact PHEV than those who felt least strongly about these issues. However, even the most inclined to consider a compact PHEV were not generally willing to pay more than a few thousand US dollars extra for the sticker price. Consistent with prior research, we found that financial and battery-related concerns remain major obstacles to widespread PHEV market penetration. We discuss how our results help to inform agent-based models of PHEV market penetration, governmental policies, and manufacturer pricing and marketing strategies to promote consumer adoption of PHEVs.
Retrieval of Flow-Field Gas Temperature and Concentration in Low-Visibility Propellant Rocket Exhaust Plumes

Abstract : Estimates have been obtained for the maximum loading level of particles in two-phase rocket exhaust plumes that still allows a reliable determination of flow-field temperature and active gas distribution using gas- only plume retrieval diagnostics. Spatial profiles of emission and absorption transverse to the plume axis and close to the nozzle exit plane were computed for various plume models using a single-scattering band model that correctly couples gas and particle radiation. Retrieval of radial gas temperature and concentration profiles from these transverse profiles were performed with an iterative Abel inversion algorithm designed for purely gaseous plumes. The retrieved profiles were compared with the model profiles to determine the error introduced by ignoring particle effects in inversion. A first-order method for accounting for particle effects was also examined. Results are presented for modeled tactical rocket plumes for candidate low-visibility propellants containing Al2O3/H2O, Carbon/HCL and ZrO2/H2O as the particulate/gas pairs.
Retinal degeneration without pigment alterations in progressive external ophthalmoplegia

A 56-year-old black man had annular visual field defects and retinal electrophysiologic dysfunction with chronic progressive external ophthalmoplegia and no pigmentary abnormalities in the fundus. Because the association of retinal disease with neurodegenerative states has generally been based on the observation of pigmentary changes, the patient's fields were erroneously interpreted as the nerve fiber bundle defects of glaucoma.
Topoisomerase inhibition by phenolic metabolites: a potential mechanism for benzene's clastogenic effects

Exposure to benzene, a human and animal carcinogen, results in the formation of structural chromosomal aberrations in the bone marrow and blood cells of animals and humans. The mechanisms underlying these clastogenic effects are unknown. Inhibition of enzymes involved in DNA replication and repair, such as topoisomerase enzymes, by the metabolites of benzene represents a potential mechanism for the formation of chromosomal aberrations. To test this hypothesis, the inhibitory effects of various phenolic and quinone metabolites of benzene on the activity of human topoisomerases I and II were studied in vitro. No inhibition of topoisomerase I was seen with any of the tested metabolites. Inhibitory effects on topoisomerase II were not observed for hydroquinone, phenol, 2,2'-biphenol, 4,4'-biphenol and catechol at concentrations as high as 500 microM. 1,4-Benzoquinone and 1,2,4-benzenetriol inhibited topoisomerase II at relatively high 500 and 250 microM concentrations, respectively. However following bioactivation using a peroxidase/H2O2 system, inhibitory effects were seen at concentrations as low as 50 microM for both phenol and 2,2'-biphenol and 10 microM for 4,4'-biphenol. The addition of reduced glutathione (GSH) to the 4,4'-biphenol and horseradish peroxidase reaction system protected topoisomerase II from inhibition suggesting that diphenoquinone or another oxidation product formed from 4,4'-biphenol might be the reactive species. These in vitro results indicate that inhibition of topoisomerase II may contribute to the clastogenic and carcinogenic effects of benzene. In addition, metabolites formed from these phenolic compounds appear to represent several new types of topoisomerase II-inhibiting compounds.
13C chemical shifts in octanethiols adsorbed on gold: a theoretical study ☆

Abstract Clusters consisting of [Au 3 SC 8 H 17 ] 2+ and [Au 5 Cl 4 SC 8 H 17 ] are employed in ab initio shielding calculations to model octanethiols adsorbed on the surface of gold nanoparticles. The isotropic shielding and its principal components are calculated using the coupled Hartree–Fock gauge-including atomic orbital (CHF-GIAO) method. The computed values compare favorably with those observed in solid state nuclear magnetic resonance (NMR) measurements of octanethiol-coated gold nanoparticles.
Exploring the intragroup conflict constructs and behaviors of African American public school children in an inner‐city conflict resolution education (CRE) program

The Consortium on Negotiation and Conflict Resolution's (CNCR) Conflict Resolution in Schools Program (CRiSP) conducted a two-year study of inner-city African American public school children to discern any conflict constructs and behaviors that were apparent in the children's intragroup interactions. This article presents findings of the CNCR study, including three emergent themes—fears of victimization, identity conflict, and core values—that were consistently apparent in the children's demonstrations of intragroup conflict constructs and behaviors.
Visual Communication: Do You See What I See?

Visual displays of data, images of subatomic to planetary-scale features, and animations of geological processes are widely used to enrich our disciplines. However, their communicative power may be dramatically different to a student and to an expert because of the need for prior knowledge and inference when interpreting visuals. To “see” equivalent visual information, the non-expert must learn the visual language of the expert. Teaching visual literacy is important to instruction at all levels and is as fundamental to a discipline as its vocabulary. The underlying foundations of visual literacy and the recognition of what one “sees” and interprets in a visual depiction are critical for enhancing student learning and for effective communication in our visually rich discipline.
Computation: Finite and Infinite Machines

From the Preface (See Front Matter for full Preface) Man has within a single generation found himself sharing the world with a strange new species: the computers and computer-like machines. Neither history, nor philosophy, nor common sense will tell us how these machines will affect us, for they do not do "work" as did machines of the Industrial Revolution. Instead of dealing with materials or energy, we are told that they handle "control" and "information" and even "intellectual processes." There are very few individuals today who doubt that the computer and its relatives are developing rapidly in capability and complexity, and that these machines are destined to play important (though not as yet fully understood) roles in society's future. Though only some of us deal directly with computers, all of us are falling under the shadow of their ever-growing sphere of influence, and thus we all need to understand their capabilities and their limitations. It would indeed be reassuring to have a book that categorically and systematically described what all these machines can do and what they cannot do, giving sound theoretical or practical grounds for each judgment. However, although some books have purported to do this, it cannot be done for the following reasons: a) Computer-like devices are utterly unlike anything which science has ever considered---we still lack the tools necessary to fully analyze, synthesize, or even think about them; and b) The methods discovered so far are effective in certain areas, but are developing much too rapidly to allow a useful interpretation and interpolation of results. The abstract theory---as described in this book---tells us in no uncertain terms that the machines' potential range is enormous, and that its theoretical limitations are of the subtlest and most elusive sort. There is no reason to suppose machines have any limitations not shared by man.
Quality of life of pancreas transplant recipients.

The quality of life outcome of 131 pancreas transplant recipients who were 1 to 11 years post-transplant were studied. Patients with a functioning pancreas graft (n=65) described their current quality of life and rated their health significantly more favourably than those with non-functioning grafts (n=66). For example, of those patients with a functioning pancreas graft, 68% expressed overall satisfaction with their life, 89% felt healthier since their transplant, and 78% reported that they could care for themselves and their routine daily activities. In contrast, of those patients without a functioning graft, only 48% expressed overall satisfaction with life (p<0.01), only 25% felt healthier since their transplant (p<0.001), and only 56% indicated they could care for themselves and their daily activities (p<0.001). Regardless of graft function, the majority of patients were comfortable with their decision to have the transplant, and most of the patients with pancreas graft function reported that they would have another transplant if their graft failed. While successful pancreas transplantation may not elevate all diabetic patients to the level of health and function of the general population, these patients report a significantly better quality of life than do those patients who remain diabetic.
AAA ATPase p97/VCP: cellular functions, disease and therapeutic potential.

p97/VCP, a member of the AAA-ATPase super family, has been associated with a wide variety of essential cellular protein pathways com prising: (i) nuclear envelope reconstruction, (ii) cell cycle, (iii) Golgi reassembly, (iv) suppression of apoptosis and (v) DNA-damage response [1-6]. In addition, vasolin-containing protein (VCP) dislodges the ubiquitinated proteins from the endoplasmic reticulum (ER) and chaperones them to the cytosol for proteasomal degradation by endoplasmic reticulum-associated degradation (ERAD) [7]. The interactions of VCP in the endoplasmic reticulum-associated degradation (ERAD) pathway determine the substrate selection for proteasomal degradation. Moreover, the interaction with VCP is also required for the ubiquitination of substrate. VCP is phosphorylated by the master cellular kinase, Akt as a mechanism to regulate ERAD [8]. These multiple interactions in protein degradation pathways points to central role of VCP in misfolded protein degradation. VCP has a poly-glutamine and ubiquitin-binding capacity and is involved in proteasomal degradation, cytosolic aggregation and processing of polyQ and polyUb aggregates in neurodegenerative and other misfolded protein diseases [9, 10]. Mutations in VCP gene are also linked to a protein deposition disorder, IBMFD [11]. We propose VCP as a therapeutic target for diseases caused by cytosolic protein aggregation or degradation of misfolded protein. We predict that selective interference of VCP interaction(s) with aberrant protein or its ERAD function will be an effective therapeutic site to rescue functional misfolded protein in diseases like cystic fibrosis and alpha-1-trypsin deficiency. The control of VCP expression is also proposed to be a potential therapeutic target in ex-polyQ-induced neurodegenerative diseases [12]. The further functional characterization of VCP and associated proteins in these diseases will help in designing of selective therapeutics.
The in vivo effects of tetrahydrocannabinol on the activity of lactate and succinate dehydrogenases in rat preovulatory follicles.

The effects of Δ9-tetrahydrocannabinol on the activities of lactate and succinate dehydrogenases in the theca interna and membrana granulosa of rat preovulatory follicles have been analysed microdensitometrically using the same injection regime employed in a previous study on steroidogenic enzymes. A small but statistically significant (18%) decrease in succinate dehydrogenase activity was observed in the theca interna, but none in any region of the membrana granulosa. Lactate dehydrogenase activity was unaffected by THC administration. Thus, a dosage and regimen sufficient to cause significant decreases in the activities of steroidogenic enzymes had little effect on succinate and lactate dehydrogenases in rat preovulatory follicles.
The Ants (Hymenoptera: Formicidae) of Jaragua National Park, Dominican Republic

This study examined ant species richness in Jaragua National Park (Pedernales Province, Dominican Republic). Ants were sampled at 15 sites during late March and early April, 2012. Habitats sampled included dry forest, beach scrub, lakeside acacia scrub, and thorn woodland. Sixty-four species from 23 genera were collected. Species richness was higher than expected, considering only 125 species had previously been reported for all of Hispaniola. Jaragua National Park is part of the Jaragua-Bahoruco-Enriquillo Biosphere Reserve. The ant species richness observed in this study suggests that the park, along with larger reserve, is successful in preserving important habitat for insects.
BRAIN IMAGING IN DEMENTIA OF THE ALZHEIMER TYPE

Neuroimaging modalities have increased understanding of brain abnormalities in dementia of the Alzheimer type (DAT), and is important in assessment of dementia syndromes by revealing focal disorders, demonstrating potentially treatable conditions, and by documenting progression of disease severity. Computed tomography (CT) and magnetic resonance imaging (MRI) have delineated structural changes in DAT, including cerebral atrophy associated with cortical sulci widening and ventricular enlargement, and deep white-matter lesions with periventricular distributions. Positron emission tomography (PET) has demonstrated diminished regional glucose metabolism at parietal and temporal lobes in DAT, while frontal hypometabolism tends to occur in more severe cases. Metabolic dysfunction assessed by PET appears to be the first indication of a degenerative cortical process in DAT, while anatomic changes on CT or MRI may become evident later in the disease process. This selective overview provides an analysis of the current status and future prospects of brain imaging in DAT.
A model for unstable shear crack propagation in pipes containing gas pressure

A tentative analysis of an unstable shear crack propagating axially in the wall of a long pipe under gas pressure is developed. Six processes known to be associated with crack propagation are treated numerically: (1) axial decomptession of the gas, (2) bulging of the pipe wall, (3) radial decompression of the gas, (4) local stress and strain intensification at the crack tip, (5) plastic deformation, and (6) ductile cracking. The treatment is quasi-static; dynamic effects in the pipe wall are ignored. Because the numerical descriptions included in the model are approximate and incomplete, several variants of the basic model are examined. The response of the model is evaluated for different line pressures, geometries, and material properties and compared with full-scale test data for 100% shear cracks. A wide range of speeds can be calculated for the limits within which the system parameters are specified including the speeds observed in practice. The bulging and decompression characteristics of the model cause the crack speed to be relatively insensitive to line pressure. Yet the calculated crack speeds are influenced by yield strength and toughness of the material. The model does not provide for nonaxial crack paths, nor does it adequately describe crack-arrest possibilities. The paper represents the first step in the analysis of a complex problem.
Transferrin receptors, iron transport and ferritin metabolism in friend erythroleukemia cells

Abstract Four aspects of iron metabolism were studied in cultured Friend erythroleukemia cells before and after induction of erythroid differentiation by dimethyl sulfoxide. (1) The binding of 125I-labeled transferrin was determined over a range of transferrin concentrations from 0.5 to 15 μM. Scatchard analysis of the binding curves demonstrated equivalent numbers of transferrin binding sites per cell: 7.78 ± 2.41 · 105 in non-induced cells and 9.28 ± 1.57 · 105 after 4 days of exposure to dimethyl sulfoxide. (2) The rate of iron transport was determined by measuring iron uptake from 59Fe-labeled transferrin. Iron uptake in non-induced cells was approx. 17 000 molecules of iron/cell per min; 24 h after addition of dimethyl sulfoxide it increased to 38 000, and it rose to maximal levels of approx. 130 000 at 72 h. (3) Heme synthesis, assayed qualitatively by benzidine staining and measured quantitatively by incorporation of 59Fe or [2-14C]glycine into cyclohexanone-extracted or crystallized heme, was not detected until 3 days after addition of dimethyl sulfoxide, when 12% of the cells were stained by benzidine and 6 pmol 59Fe and 32 pmol [2-14C]glycine were incorporated into heme per 108 cells/h. After 4 days, 60% of the cells were benzidine positive and 34 pmol 59Fe and 90 pmol [2-14C]glycine were incorporated into heme per 108 cells/h. (4) The rate of incorporation of 59Fe into ferritin, measured by immunoprecipitation of ferritin by specific antimouse ferritin immunoglobulin G, rose from 4.4 ± 0.6 cells to 18.4 ± 1.3 pmol 59Fe/h per 108 cells 3 days after addition of dimethyl sulfoxide, and then fell to 11.6 ± 3.1 pmol 4 days after dimethyl sulfoxide when heme synthesis was maximal. These studies indicate that one or more steps in cellular iron transport distal to transferrin binding is induced early by dimethyl sulfoxide and that ferritin may play an active role in iron delivery for heme synthesis.
The role of surface tension in magnetorheological adhesion

Magnetorheological (MR) fluids are colloidal suspensions of magnetizable particles that exhibit an increase in the yield stress and in the apparent viscosity when a magnetic field is applied. It has been shown previously that MR fluids can also be used for field-controlled static adhesion to non-magnetic surfaces. Here we demonstrate the important role surface tension plays in this adhesion and that the adhesive property is not related to the shear resistance of the field-dependent yield stress, as previously proposed.
Thromboembolism coincident with tourniquet deflation during total knee arthroplasty

Despite prophylactic therapy, pulmonary embolism remains the leading cause of perioperative mortality in patients undergoing total knee arthroplasty (TKA). We used transoesophageal echocardiography to monitor 29 consecutive patients during TKA. Showers of substantial amounts of echogenic material, lasting for 3-15 min, were visible in the right atrium and ventricle within 10-15 s of tourniquet deflation in all patients. A 3 x 6 mm fresh thrombus was aspirated from the central circulation of one patient. Another patient, who had had a Greenfield filter placed for previous thromboembolism, showed very little echogenic material after tourniquet deflation. The composition and importance of these echogenic emboli remain uncertain.
Realism and the Kantian Tradition: A Revisionist Account:

In contemporary international political theory, ‘Cosmopolitanism’ is typically juxtaposed to ‘Realism’, with many varieties of the former building on Kantian moral and political ideals, and the lat...
Social Relations Undone: Disciplinary Divergence and Departmental Politics at Harvard, 1946-1970

This article examines the failed convergence of sociology, social psychology, cultural anthropology, and clinical psychology in Harvard’s Department of Social Relations. The analysis shows that from its inception, the department was torn by fundamental contradictions involving membership criteria, stratification, the opposed needs of faculty and students, and the requisites of disciplinary autonomy. These conflicts, which were especially intense with regard to psychology, ultimately made the department ungovernable and led to the restoration of earlier administrative boundaries.
Factors concerned in tyrosine metabolism.

Abstract Vitamin B12, the active agent for treatment of pernicious anemia, was found to decrease the excretion of tyrosine metabolites by guinea pigs on a vitamin C-deficient diet. The nature of the action with dosage at the microgram level was similar to liver extract effect, either with single or repeated injections. The relation of B12 to vitamin C was studied in relation to vitamin C saturation. The 20-μg. dose of B12 was found to lose its effect in prolonged scurvy, which indicates the requirement of vitamin C for the B12 effect. No clear correlation can be evaluated between tissue vitamin C and the B12 effect; liver vitamin C may play a more important part in the B12 effect. The vitamin C depletion method was applied to a study of the folic acid effect in tyrosine metabolism. From these experiments it was concluded that not only is a given level of folic acid necessary to produce an effect on tyrosine metabolism, but, also, with a given effective dose of folic acid, a minimum ascorbic acid saturation must be achieved.
Effects of platinum and palladium impregnation on the performance and durability of automobile exhaust oxidizing catalysts

Abstract The performance and durability properties of noble metal-alumina oxidation catalysts are strongly influenced by the relative location of the metals along the radius of the porous catalyst pellets. Five Pt- and Pd-containing catalysts were prepared by systematically varying the noble-metal distribution along the radius of the catalyst pellets. The catalysts were poisoned on a dynamometer or sintered in a high-temperature furnace. The results showed sizable improvements in both steady-state and light-off performance when the catalyst had an outer shell of Pt and an inner shell of Pd.
Alignment of the 2P state of 2-MeV/amu heliumlike sulfur

The $2^{1}P$ and $2^{3}P$ levels of two-electron S xv have been aligned by collision at 2 MeV/amu with carbon atoms in a foil. The degree of alignment is obtained by analysis of the normalized angular distribution of $K$ x-ray radiation measured in high resolution with a pivoted plane-crystal Bragg spectrometer. The mean cross-section ratio $\frac{{\ensuremath{\sigma}}_{0}}{{\ensuremath{\sigma}}_{1}}$ for population of the $m=0$ sublevel relative to the $m=\ifmmode\pm\else\textpm\fi{}1$ sublevels of the $2P$ parent state is obtained by analysis of the $1^{1}S\ensuremath{-}2^{1}P$ and $1^{1}S\ensuremath{-}2^{3}P$ transition intensities. The result $\frac{{\ensuremath{\sigma}}_{0}}{{\ensuremath{\sigma}}_{1}}=1.79\ifmmode\pm\else\textpm\fi{}0.1$ leads to the polarization fractions $P(^{1}P)=0.28\ifmmode\pm\else\textpm\fi{}0.05$, and $P(^{3}P)=\ensuremath{-}0.16\ifmmode\pm\else\textpm\fi{}0.03$, in good agreement with results obtained by an independent analysis, and in excellent agreement with coupled-states calculations of Reading et al. Comparison with other theories is also made.
Experimental evidence for the existence of a Ramsauer—Townsend minimum in liquid CH4 and liquid Ar (Kr and Xe)

Abstract Experimental evidence for the existence of a Ramsauer—Townsend minimum in the electron scattering cross section for liquid CH 4 and liquid Ar (Kr and Xe) is provided from: (i) comparisons of thermal electron mobilities in gases with those in liquids, (ii) changes in the electron mobility with gas density, and (iii) the dependence of the electron mobility on temperature for liquids whose V 0 , the energy of the electron state in the liquid, is ⩽ 0 eV.
Direct interaction between the Gulf Stream and the shelfbreak south of New England

Sea surface temperature imagery, satellite altimetry and a surface drifter track reveal an unusual tilt in the Gulf Stream path that brought the Gulf Stream to 39.9°N near the Middle Atlantic Bight shelfbreak—200 km north of its mean position—in October 2011, while a large meander brought Gulf Stream water within 12 km of the shelfbreak in December 2011. Near-bottom temperature measurements from lobster traps on the outer continental shelf south of New England show distinct warming events (temperature increases exceeding 6°C) in November and December 2011. Moored profiler measurements over the continental slope show high salinities and temperatures, suggesting that the warm water on the continental shelf originated in the Gulf Stream. The combination of unusual water properties over the shelf and slope in late fall and the subsequent mild winter may affect seasonal stratification and habitat selection for marine life over the continental shelf in 2012.
Fibroblast expression of the coactivator p300 governs the intensity of profibrotic response to transforming growth factor β

Objective Transforming growth factor β (TGFβ) induces profibrotic responses in normal fibroblasts, and plays a fundamental role in the pathogenesis of fibrosis in scleroderma (systemic sclerosis [SSc]). The intensity of cellular responses elicited by cytokines is modulated by transcriptional coactivators such as the histone acetylase p300. The objective of these studies was to delineate the physiologic role of p300 in Smad-dependent profibrotic responses elicited by TGFβ. Methods Ectopic p300 was transiently expressed in normal dermal fibroblasts. Cellular p300 levels were suppressed using p300-specific ribozymes. The regulation of gene expression was examined by transient transfection assays, Northern blotting, and immunoblot analysis. The expression of p300 in normal and scleroderma fibroblasts was evaluated by confocal microscopy and immunoblotting, and p300 levels in skin from mice with experimental scleroderma were assessed by immunohistochemistry. Results In normal fibroblasts, TGFβ induced an increase in the levels of p300. Forced expression of ectopic p300 in these cells dramatically enhanced the magnitude of TGFβ responses, whereas selective depletion of p300 using ribozyme resulted in abrogation of TGFβ-induced collagen synthesis and promoter activity. Furthermore, TGFβ lost its ability to induce Smad-dependent transcription in p300-depleted fibroblasts. These responses could be fully rescued with ectopic p300. Abrogation of Smad-mediated TGFβ signaling was not due to alterations in the levels or the ligand-dependent phosphorylation or intracellular trafficking of endogenous Smads. Immunohistochemical analysis demonstrated substantially increased p300 expression in lesional skin from mice with chronic graft-versus-host disease, an animal model of scleroderma. Furthermore, levels of p300 were 2–3–fold higher in cultured fibroblasts derived from SSc patients than in fibroblasts from matched normal controls. Conclusion These results establish, for the first time, that the coactivator histone acetylase p300, itself a target of TGFβ regulation, is an essential component of the cellular TGFβ signal transduction pathways mediating stimulation of collagen synthesis in fibroblasts. Since the cellular abundance of p300 appears to govern the intensity of profibrotic responses elicited by TGFβ, elevated p300 expression in lesional tissue may contribute to the progression of skin fibrosis in scleroderma.
Catastrophic rock avalanche 3600 years BP from El Capitan, Yosemite Valley, California.

Large rock slope failures from near-vertical cliffs are an important geomorphic process driving the evolution of mountainous landscapes, particularly glacially steepened cliffs. The morphology and age of a 2·19 × 106 m3 rock avalanche deposit beneath El Capitan in Yosemite Valley indicates a massive prehistoric failure of a large expanse of the southeast face. Geologic mapping of the deposit and the cliff face constrains the rock avalanche source to an area near the summit of ∼8·5 × 104 m2. The rock mass free fell ∼650 m, reaching a maximum velocity of 100 m s−1, impacted the talus slope and spread across the valley floor, extending 670 m from the base of the cliff. Cosmogenic beryllium-10 exposure ages from boulders in the deposit yield a mean age of 3·6 ± 0·2 ka. The ∼13 kyr time lag between deglaciation and failure suggests that the rock avalanche did not occur as a direct result of glacial debuttressing. The ∼3·6 ka age for the rock avalanche does coincide with estimated late Holocene rupture of the Owens Valley fault and/or White Mountain fault between 3·3 and 3·8 ka. The coincidence of ages, combined with the fact that the most recent (AD 1872) Owens Valley fault rupture triggered numerous large rock falls in Yosemite Valley, suggest that a large magnitude earthquake (≥M7.0) centered in the south-eastern Sierra Nevada may have triggered the rock avalanche. If correct, the extreme hazard posed by rock avalanches in Yosemite Valley remains present and depends on local earthquake recurrence intervals. Published in 2010 by John Wiley & Sons, Ltd.
Attenuation and recovery of evoked overflow of striatal serotonin in rats treated with neurotoxic doses of methamphetamine.

Repeated administration of methamphetamine to animals can lead to long-lasting decreases in striatal monoamine content. In the present study, the effects of neurotoxic doses of methamphetamine on basal and evoked overflow of striatal serotonin and of its primary metabolite 5-hydroxyindoleacetic acid were examined in awake rats using in vivo microdialysis. Male Fischer-344 rats were administered methamphetamine (5 mg/kg, s.c.) or saline four times in 1 day at 2-h intervals. Microdialysis studies were carried out 1 week, 1 month, and 6 months later. At 1 week posttreatment there were significant decreases in potassium- and amphetamine-evoked overflow of serotonin in the striatum of the methamphetamine-treated animals. Basal extracellular levels of 5-hydroxyindoleacetic acid but not of serotonin were also decreased. Evoked overflow of serotonin recovered by 1 month, and extracellular levels of 5-hydroxyindoleacetic acid had recovered by 6 months. Tissue levels of serotonin and 5-hydroxyindoleacetic acid were decreased at 1 week posttreatment but back to control levels by 1 month after treatment. These results indicate that presynaptic serotonergic functioning is attenuated in the striatum of rats treated 1 week earlier with neurotoxic doses of methamphetamine. However, in the model used, the changes are transient, and recovery can occur within 1-6 months posttreatment.
Convergence of approximations in feedback control of structures

Convergence of linear quadratic regulator (LQR) problems in structures is discussed. The abstract formulation of the system using a variational framework based on sesquilinear forms is considered. Since convergence theorems require uniform stabilizability of the finite-dimensional approximating system, we present a detailed proof of a fundamental lemma due to Banks and Ito [1] which can be used to easily verify this condition for many applications. Existing results for the well posedness of the infinite-dimensional system and convergence of Galerkin approximations are summarized.
Linking the molecular evolution of avian beta (β) keratins to the evolution of feathers

Feathers of today's birds are constructed of beta (β)-keratins, structural proteins of the epidermis that are found solely in reptiles and birds. Discoveries of “feathered dinosaurs” continue to stimulate interest in the evolutionary origin of feathers, but few studies have attempted to link the molecular evolution of their major structural proteins (β-keratins) to the appearance of feathers in the fossil record. Using molecular dating methods, we show that before the appearance of Anchiornis (∼155 Million years ago (Ma)) the basal β-keratins of birds began diverging from their archosaurian ancestor ∼216 Ma. However, the subfamily of feather β-keratins, as found in living birds, did not begin diverging until ∼143 Ma. Thus, the pennaceous feathers on Anchiornis, while being constructed of avian β-keratins, most likely did not contain the feather β-keratins found in the feathers of modern birds. Our results demonstrate that the evolutionary origin of feathers does not coincide with the molecular evolution of the feather β-keratins found in modern birds. More likely, during the Late Jurassic, the epidermal structures that appeared on organisms in the lineage leading to birds, including early forms of feathers, were constructed of avian β-keratins other than those found in the feathers of modern birds. Recent biophysical studies of the β-keratins in feathers support the view that the appearance of the subfamily of feather β-keratins altered the biophysical nature of the feather establishing its role in powered flight. J. Exp. Zool. (Mol. Dev. Evol.) 316:609–616, 2011. © 2011 Wiley Periodicals, Inc.
Conduction of a weakly interacting one-dimensional electron gas through a single barrier.

Scattering from a localized potential of arbitrary strength is found for weakly interacting electrons. Poor man's renormalization group procedure allows us to calculate the renormalized transmission amplitudes at any energies. Simple formulas that describe the conductance at any temperature are derived. In the presence of the electron-electron backscattering, the low-temperature conductance deviates from the results of Luttinger liquid theory. In particular, the temperature dependence of the conductance may become nonmonotonic. In the presence of a magnetic field, backscattering gives rise to a peak in the differential conductance at bias equal to the Zeeman splitting.