cssi/SciSciGPT-SciSciNet huggingface dataset:
Materials Science: An Intermediate Text

1. Microstructural analysis 2. Symmetry 3. Miller-Bravais system 4. Stereographic projection 5. Crystal defects 6. Phase diagrams 7. Free energy basis for phase diagrams 8. Ordering of solid solutions 9. Diffusion 10. Freezing 11. Phase transformations 12. Surfaces 13. Bonding 14. Sintering 15. Amorphous materials 16. Liquid crystals 17. Molecular morphology 18. Magnetic materials 19. Porous and novel materials 20. Shape memory and super-elasticity 21. Calculations.
Signs of Mothering in the Built Environment

Signs are a routine aspect of our built environment. They give us directions,tell us what behaviors are spatially appropriate, and indicate who belongs where. Signsalso reveal gendered aspects of our culture, and have tremendous impact onlegitimating and promoting particular practices of mothering. This paper explorestwo types of signs particularly relevant to mothering: signs demarcating breast feeding friendlylocations, and signs designating parking spaces for pregnant women and motherswith children in tow.The prominent display of the international symbol for breastfeeding constructs someworkplaces and shops as mother-and-child-friendly locations. In doing so, the signs aremerging family life with consumptive practices, making claims about the businessﾒcommitment to a particular set of ﾓfamily values,ﾔ and offering tacit exemption tobusinesses that eschew breastfeeding mothers. The demarcation of parking spaces forpregnant and mothering women similarly constructs a family-friendly consumer space,while making assumptions about the physical abilities of pregnant and mothering women.In these parking spaces, notions of disability, authority, and consumerism challenge ourlegal and political foundations of equity and advancement.The implications of these signs of mothering in the built environment reveal a semiotic ofrepresentative promotion that we should not take for granted, and which this paperproposes to explore.
Robust/adaptive observers for systems having uncertain functions with unknown bounds

A novel robust/adaptive observer is presented for state reconstruction of nonlinear systems with uncertainty having unknown bounds. The observer uses a nonlinear gain which is continuously adapted to guarantee a uniformly bounded and convergent observation error. Some generalizations to known waveform type disturbances and measurement uncertainties are pointed out.
Fuzzy logic models of the relationships among communication satisfaction factors and organizational commitment in three Australian organizations

The usefulness of Takagi-Sugeno-Kang inference systems for the study of organizational communication was investigated. Specifically, the relationship between communication satisfaction and commitment in three Australian organizations is examined. The relationships among communication satisfaction's principal components and organizational commitment are modeled using a TSK system. TSK systems have not been used to model communication systems previously. One objective is to see if more information could be gained about the relationship using fuzzy logic. The current research also investigates the unique aspects of using fuzzy logic to examine variables in the social sciences. TSK inference systems demonstrate the ability to provide fresh perspectives on organizational communication.
Robot Programming by Demonstration with Crowdsourced Action Fixes

Programming by Demonstration (PbD) can allow end-users to teach robots new actions simply by demonstrating them. However, learning generalizable actions requires a large number of demonstrations that is unreasonable to expect from end-users. In this paper, we explore the idea of using crowdsourcing to collect action demonstrations from the crowd. We propose a PbD framework in which the end-user provides an initial seed demonstration, and then the robot searches for scenarios in which the action will not work and requests the crowd to fix the action for these scenarios. We use instance-based learning with a simple yet powerful action representation that allows an intuitive visualization of the action. Crowd workers directly interact with these visualizations to fix them. We demonstrate the utility of our approach with a user study involving local crowd workers (N=31) and analyze the collected data and the impact of alternative design parameters so as to inform a real-world deployment of our system.
Novel measurement of hyperfine interactions in solids: 207Pb3+ in YPO4 and LuPO4

Stable trivalent lead impurities have been observed at room temperature in ''flux-grown'' single crystals of YPO/sub 4/ and LuPO/sub 4/ by electron paramagnetic resonance. Because of a fortuitous set of circumstances, a unique measurement of the hyperfine constant of /sup 207/Pb/sup 3 +/ in these materials was possible. The resulting values are the largest ever observed for the trivalent lead ion in a solid. A super hyperfine interaction with /sup 31/P neighbors has also been measured and, surprisingly, this interaction is larger for the second /sup 31/P neighbors than for the first /sup 31/P neighbors.
Differences in tobacco product use among past month adult marijuana users and nonusers: Findings from the 2003–2012 National Survey on Drug Use and Health.

INTRODUCTION This study assessed differences in individual tobacco product use between past month marijuana users and nonusers, and trends in overall tobacco use and use of specific tobacco products among marijuana users. METHODS Data were obtained from 378 459 adults participating in the 2003-2012 National Survey on Drug Use and Health, a cross-sectional, household interview survey conducted annually. Data from the most recent 2 years (2011-2012) were used to assess differences in the prevalence of various tobacco products by past month marijuana status. Data from all years were used to assess historical trends in overall tobacco use, and use of cigarettes, cigars, and blunts among marijuana users; trend significance was assessed using orthogonal polynomials. RESULTS From 2011-2012, the prevalence of any past month tobacco use among the 9727 past month marijuana users was 68.6% excluding blunts, and 78.3% including blunts (vs. 25.3% for nonusers, P < .0001); 77.3% of past month marijuana users reported past month combusted tobacco use (vs. 23.4% of non-MJ users, P < .0001). By product, 60.1% of past month marijuana users reported past month cigarette use, 42.0% reported past month blunt use, and 20.6% reported past month cigar use. Overall, adjusted trends in past month cigarette use decreased, while trends in past month blunt use increased; cigar use did not change. DISCUSSION Tobacco use is highly prevalent among adult marijuana users and represents an important potential comorbidity of marijuana use. In light of increasing policies legalizing marijuana, it is critical to monitor changes in overall and specific tobacco product use.
XVI. Superfluidity and the two dimensional XY model

Abstract Recent results for the two dimensional XY model are reviewed, with an emphasis on a discrete gauge symmetry implicit in this picture of magnetism. An exact relationship between the critical exponent η in this model and the superfluid density in a helium film should allow a precise experimental check of competing theoretical predictions.
Honey Bees as Indicators of Radionuclide Contamination: Comparative Studies of Contaminant Levels in Forager and Nurse Bees and in the Flowers of Three Plant Species

Two separate field experiments were conducted as part of ongoing research concerning the use of honey bees (Apis mellifera) as indicators of environmental radionuclide contamination. The experiments were conducted in a study site containing radionuclide contamination above background levels. The first experiment compared levels of radionuclides found in forager bees to levels found in nurse bees. Bees were collected from colonies, analyzed for concentrations of radionuclides, and the results were compared using statistical methods. Results indicated that there is no significant difference between the contaminant levels in forager and nurse bees. A second experiment compared the levels of radionuclides found in the flowers of three plant species growing in the study site: salt cedar (Tamarix ramosissima), white sweet clover (Melilotus albus), and rabbit brush (Chrysothamnus nauseosus). Results indicated that there is no significant difference in the amounts of radionuclides found in the flowers of these three plants.
Adsorption of pyrrole on Fe(II)Y, Fe(III)Y, Cu(I)Y, and Cu(II)Y zeolites

Pyrrole-type compounds are widely found in natural crude oil and are suspected poisons of refining catalysts such as Y zeolite. Transition metal impurities are present in zeolite and its binder. Metal concentration on the catalyst often increases during the refining process since these impurities are also present in the crude. Understanding the adsorption behavior of pyrrole on transition metal exchanged zeolites can thus provide insights into the problem of catalyst deactivation. In addition, since pyrrole-type compounds also exist in shale oil and are believed to be actively involved in the formation of gum during storage, this study may also offer a means to remove these compounds from fuel and provide a solution to this fuel instability problem. In this paper the authors report the results obtained from the adsorption of pyrrole on Fe- and Cu-exchanged Y zeolites. The study is aimed at exploring the roles the transition metal ions play in the adsorption and reaction of pyrrole on zeolites. Both the higher oxidation state ions Fe(III) and Cu(II) and the lower oxidation state ions Fe(II) and Cu(I) were examined. In situ IR was the major tool used for monitoring the surface reactions, and other analytical methods were also used tomore » characterize the surface and the products. 20 references.« less
Building Professional Learning Communities Within a University—Public School Partnership

Building faculty or professional learning communities is an idea that has come of age. This article describes work being done within the Brigham Young University (BYU)–Public School Partnership to form and sustain such communities across higher and public education and in ways consistent with the four aims of the Agenda for Education in a Democracy embraced by the National Network for Educational Renewal. Noting that too little attention has been given to determining the purposes of learning communities, Partnership initiatives supporting the Agenda and designed to create learning communities are described and results briefly presented.
Low-resolution vehicle tracking using dense and reduced local gradient features maps

We present a novel method to quickly detect and track objects of low resolution within an image frame by comparing dense, oriented gradient features at multiple scales within an object chip. The proposed method uses vector correlation between sets of oriented Haar filter responses from within a local window and an object library to create similarity measures, where peaks indicate high object probability. Interest points are chosen based on object shape and size so that each point represents both a distinct spatial location and the shape segment of the object. Each interest point is then independently searched in subsequent frames, where multiple similarity maps are fused to create a single object probability map. This method executes in real time by reducing feature calculations and approximations using box filters and integral images. We achieve invariance to rotation and illumination, because we calculate interest point orientation and normalize the feature vector scale. The method creates a feature set from a small and localized area, allowing for accurate detections in low resolution scenarios. This approach can also be extended to include the detection of partially occluded objects through calculating individual interest point feature vector correlations and clustering points together. We have tested the method on a subset of the Columbus Large Image Format (CLIF) 2007 dataset, which provides various low-pixel-on-object moving and stationary vehicles with varying operating conditions. This method provides accurate results with minimal parameter tuning for robust implementation on aerial, low pixel-on-object data sets for automated classification applications.
On biodiversity access, intellectual property rights, and conservation

Abstract Recent international agreements such as the Convention on Biological Diversity and the Trade-Related Intellectual Property Rights have called for increased mutual transfer of biodiversity and biotechnology between poor and rich countries. These agreements also call for the protection of intellectual property rights (IPR) on biotechnology transferors in the receiving countries. This paper examines the biodiversity conservation implications of providing physical access and IPR protection to foreign consumers of biodiversity. An integrated model of optimal resource extinction and shared resource harvesting game is presented. The model results show that, as foreign and indigenous users compete for the same open-access resource, optimal extinction may occur as a noncooperative equilibrium under certain bioeconomic conditions. Extinction may be prevented by forging successful cooperation between consumers, initiating a joint harvesting process. Depending upon the model parameters, even under cooperation, increased patent protection and physical access either promotes the conservation of biodiversity or enhances its physical exploitation. Patent protection and resource access must, therefore, be developed carefully by biodiversity-rich countries to successfully balance their domestic conservation and socioeconomic goals.
EFFECT OF LATTICE DISORDER ON THE SUPERCONDUCTING TRANSITION TEMPERATURE.

A theory is presented to explain the dependence of the superconducting transition temperature ${T}_{c}$ on the changes in the phonon frequency spectrum and electronic density of states which result from lattice disorder. Numerical calculations of ${T}_{c}$ are presented for films composed of crystalline granules, for films composed of amorphous granules, and for homogeneous amorphous metals. The calculations are in good agreement with experimental values of ${T}_{c}$.
Dynamical transitions of Turing patterns

This paper is concerned with the formation and persistence of spatiotemporal patterns in binary mixtures of chemically reacting species, where one of the species is an activator, the other an inhibitor of the chemical reaction. The system of reaction–diffusion equations is reduced to a finite system of ordinary differential equations by a variant of the centre-manifold reduction method. The reduced system fully describes the local dynamics of the original system near transition points at the onset of instability. The attractor–bifurcation theory is used to give a complete characterization of the bifurcated objects in terms of the physical parameters of the problem. The results are illustrated for the Schnakenberg model.
ALKALINE QUENCHING OF BACTERIORHODOPSIN TRYPTOPHANYL FLUORESCENCE: EVIDENCE FOR AQUEOUS ACCESSIBILITY OR A HYDROGEN‐BONDED CHAIN

— Comparison between Trp fluorescence yields of membrane-bound bacteriorhodopsin (BR) and retinylidene-free bacterioopsin (BO) is consistent with a model in which all eight Trp residues are active fiuorophores in the latter, while the emission of all but two residues in the former is lost by energy transfer to retinal. The visible chromophore of BR is progressively bleached with increasing pH. Up to pH 12 this bleaching is reversed on reneutralization; but above this the change is irreversible with the appearance of a new absorption band characteristic of free retinal. Emission yields for both proteins decrease with increasingly alkaline pH in a manner typical of energy transfer to weakly-fluorescent tyrosinate. The limiting yields, reached at a pH corresponding to that producing irreversible bleaching of the visible chromophore, agree with an integral value of one remaining active Trp fluorophore in BR and between one and two in BO and show that the bulk of Trp are within the 11 A Forster energy-transfer distance of Tyr accessible to OH−. Current models of the native protein structure of BR arrange the polypeptide chain primarily in a bundle of seven helical segments with axes perpendicular to the lipid bilayer plane and with buried polar residues, including Trp and Tyr, located at intrahelical surfaces. An interpretation of the observed accessibility of buried Tyr to OH− is that an aqueous region exists within the protein structure. Moreover, this putative aqueous region must be close to the retinylidene chromophore and thus may be associated with the light-driven ion transport system. The results are also compatible with energy transfer to internal Tyr residues which are connected via a chain of phenolate hydrogen bonds to a surface Tyr.
EXPERIMENTAL OBSERVATIONS ON IRRADIATED, NORMAL, AND PARTIALLY PARATHYROIDECTOMIZED RABBITS : I. THE EFFECTS OF PARTIAL PARATHYROIDECTOMY.

Previous irradiation of rabbits with ultra-violet light, with a consequent hypertrophy of the parathyroid glands, resulted in some degree of protection to these animals, when part of the parathyroid tissue was extirpated. This fact indicates that the remaining hyperplastic tissue was potentially active, and that the increased factor of safety represented by this condition of the remaining tissue resulted in less loss of blood calcium, a more rapid initiation of recovery, and an absence of the rise in the inorganic phosphorus of the blood serum which was a characteristic result of partial parathyroidectomy in normal rabbits. A fall in calcium in all the irradiated rabbits, without a corresponding rise in phosphorus, shows that the drop in calcium is the primary reaction, and a rise in phosphorus a secondary reaction following parathyroidectomy. But the relation of the rise in phosphorus to the development of tetany remains obscure.
Spontaneous in vivo retrovirus-infected T and B cells, but not dendritic cells, mediate antigen-specific Fas ligand/Fas-dependent apoptosis of anti-retroviral CTL

C57BL/6 (H-2b), but not spontaneous virus-expressing AKR.H-2b congenic, mice generate retrovirus-specific CD8+ CTL responses to the immunodominant Kb-restricted epitope, KSPWFTTL. AKR.H-2b non-responsiveness is mediated by a peripheral tolerance mechanism. When co-cultured with primed B6 antiviral pCTL, AKR.H-2b splenocytes are recognized by the antiviral TcR as "veto" cells, which inhibit by an exquisitely virus-specific, MHC-restricted, veto cell FasL/responder T cell Fas, mediated apoptotic mechanism. Here, AKR.H-2b thymus, lymph node, and bone marrow cells are also shown to inhibit antiviral CTL generation. Purified AKR.H-2b CD4+ and CD8+ T cells, and B cells, served effectively as FasL-dependent veto cells. In contrast, AKR.H-2b dendritic cells (DC) did not efficiently veto antiviral CTL responses, despite expressing sufficient MHC class I/viral peptide complexes for TcR recognition. AKR.H-2b DC also expressed FasL mRNA and cell surface protein, albeit at a lower level than AKR.H-2b T and B cells. These findings suggest a fail-safe escape mechanism by virus-infected cells for escape from CTL-mediated immunity.
Copolymerization of dimethyl propene-2-phosphonate and styrene using anionic initiation

Dimethyl propene-2-phosphonate has been copolymerized with styrene by the use of n-butyllithium and sodium naphthalene as initiators. Only a few mole per cent of the phosphorus containing monomers was incorporated in the copolymer in any case.
Confluent mixing efficiency in flow-injection systems

Abstract The mixing efficiency of a standard manifold and a ball mixer for flow-injection systems were studied and compared. The reactions of ozone with indigo trisulphonic acid and chlorate ion with iodide ion in acidic medium were used as test reactions for the investigation. Mixing efficiency was shown to approach unity for both the ball mixers and the standard flow-injection analysis manifold. Effects of reaction rates, dispersion of the injected sample and diffusion are studied. As expected the faster the rate of the reaction the more marked the effect of the mixing efficiency.
Striking effects of coupling mutations in the acceptor stem on recognition of tRNAs by Escherichia coli Met-tRNA synthetase and Met-tRNA transformylase.

We measured kinetic parameters in vitro and directly analyzed aminoacylation and formylation levels in vivo to study recognition of Escherichia coli initiator tRNA mutants by E. coli Met-tRNA synthetase and Met-tRNA transformylase. We show that, in addition to the anticodon sequence, mutations in the "discriminator" base A73 also affect aminoacylation. An A73----U change has a small effect, but a change to G73 or C73 significantly lowers Vmax/Kappm for in vitro aminoacylation and leads to appreciable accumulation of uncharged tRNA in vivo. Significantly, coupling of the G73 mutation with G72, a neighboring-base mutation, results in a tRNA essentially uncharged in vivo. Coupling of C73 and U73 mutations with G72 does not have such an effect. Elements crucial for Met-tRNA transformylase recognition of tRNAs are located at the end of the acceptor stem. These elements include a weak base pair or a mismatch between nucleotides (nt) 1 and 72 and base pairs 2.71 and 3.70. The natures of nt 1 and 72 are less important than the fact that they do not form a strong Watson-Crick base pair. Interestingly, the negative effect of a C.G base pair between nt 1 and 72 is suppressed by mutation of the neighboring nucleotide A73 to either C73 or U73. The presence of C73 or U73 could destabilize the C1.G72 base pair at the end of an RNA helix. Thus, in some tRNAs, the discriminator base could affect stability of the base pair between nt 1 and 72 and thereby the structure of tRNA at the end of the acceptor stem.
The effect of minimum wages on actual wages in formal and informal sectors in Costa Rica

Summary As in many economies, wage gaps between formal and informal sectors have been persistent in Costa Rica. Using 12 years of microdata, we test whether increases in minimum wages raise actual wages; we find they not only raise wages in large urban and rural enterprises (traditionally referred to as formal), but they also raise wages of workers covered by minimum wage legislation in what are traditionally regarded as informal sectors where the legislation is often considered not to be enforced: small urban and small rural enterprises. Furthermore, minimum wages raise wages in these informal sectors more than in larger firms and hence work to reduce wage differentials between the larger and smaller firms. However, minimum wages have no significant impact on wages in the informal sector not covered by minimum wage legislation, the self-employed.
Inverted vs spanning the cusp boundary layer

We present several examples of dayside inverted Vs in which ion convection and energy dispersion appear to span the region of both open and closed field lines. All of these examples occur in the region generally called the low-latitude boundary layer or the cusp boundary layer and suggest a connection between closed field lines of the dayside auroral region and open field lines of the dayside cusp. One explanation is that plasma in the cusp boundary layer on closed field lines convects across field lines in a smooth fashion into the cusp. Such cross-field-line convection may be possible in regions of finite conductivity and strong currents, where the field can diffuse through the plasma. Another explanation for the observations is that they represent the mid-altitude manifestation of merging at the dayside magnetopause and the opening of previously closed field lines.
Spontaneous cortical slow-potential shifts and choice reaction time performance

Abstract EEGs from Fz, Cz and Pz locations (reference — right mastoid) were obtained from 36 adults. For experimental trials the Fz slow potentials (SP) were determined for a pretask interval of: a 3 sec baseline, followed by a 2.5 sec SP shift, in either negative (3.5 μV) or positive (1.5 μV) direction, and maintenance at this level for another 2.5 sec. When this criterion was met the stimuli for a choice RT task were presented (potential-related event, PRE), which required a button-press response with the right or left hand for differing stimulus configurations. During subsequent control sessions subjects were tested without pretask criterion SP shifts, with yoked pretask intervals from the experimental sessions. For the experimental conditions the mean RTs were significantly faster and less variable with the negative than with the positive SP shift condition. For the control conditions mean RTs were somewhat faster for the positive than for the negative criterion, which might be attributed to the more variable pretask intervals during the latter polarity condition. For confirmation of the cortical localization of this effect, the experimental session was replicated with corresponding negative and positive SP shift criteria from Pz. No significant differences among means and standard deviations of RTs were found. SP shifts from criterion electrodes (Fz or Pz) were significantly greater in mean amplitude than the concomitant SP shifts from the other electrodes. The present findings demonstrate the feasibility of the PRE methodology for investigations of human brain functions.
Pressure and Temperature Dependences of the Dielectric Properties of the Perovskites BaTi O 3 and SrTi O 3

The dielectric properties of single-crystal and ceramic BaTi${\mathrm{O}}_{3}$ and of single-crystal SrTi${\mathrm{O}}_{3}$ were investigated as functions of hydrostatic pressure to 25 kbar and temperature to 150\ifmmode^\circ\else\textdegree\fi{}C. The Curie point of BaTi${\mathrm{O}}_{3}$ decreased linearly with increasing pressure, but at a rate which varied from -4.6 to -5.9\ifmmode^\circ\else\textdegree\fi{}C/kbar for different samples. Its spontaneous polarization ${P}_{s}$ decreased slowly (2% per kbar) up to the transition pressure, where it dropped rapidly. This change in ${P}_{s}$ is primarily due to the displacement of the Curie point to lower temperatures. At constant temperature, the dielectric constant $\ensuremath{\epsilon}$ in the cubic phase of both compounds obeys the relationship $\ensuremath{\epsilon}=\frac{{C}^{*}}{(p\ensuremath{-}{p}_{0})}$. At 25\ifmmode^\circ\else\textdegree\fi{}C, ${C}^{*}=2.8\ifmmode\times\else\texttimes\fi{}{10}^{4}$ kbar and ${p}_{0}=18.5$ kbar for pure single-crystal BaTi${\mathrm{O}}_{3}$, and ${C}^{*}=1.2\ifmmode\times\else\texttimes\fi{}{10}^{4}$ kbar and ${p}_{0}=\ensuremath{-}40$ kbar for single-crystal SrTi${\mathrm{O}}_{3}$. Both ${C}^{*}$ and ${p}_{0}$ change with temperature. Similarly, the Curie-Weiss constant $C$ and temperature ${T}_{0}$ change with pressure. The temperature dependence of $\ensuremath{\epsilon}$ is separated into volume-dependent and volume-independent contributions, and it is shown that the change of the infrared polarizability with temperature at constant volume is the predominant factor in determining the change in $\ensuremath{\epsilon}$.
Audience Counts and Reporting System: Establishing a Cyber-Infrastructure for Museum Educators

Philanthropic and government organizations increasingly require quantitative and qualitative data as key components of program evaluation and as precursors to continued funding. The Smithsonian Institution has been challenged in recent years to demonstrate the value of educational programs delivered to the general public and to more specialized, niche audiences. This article describes an initiative involving Georgetown and Liberty University researchers working with The Smithsonian Center for Education and Museum Studies (SCEMS) and the Smithsonian Council of Education Directors (SCED) to develop novel methodologies and technologies to capture, analyze, and disseminate accurate and reliable quantitative attendance data from 27 independent education organizations across Central and North America. The difficulties inherent in museum education assessment are discussed, as well as how e-science was designed and implemented in concert with user-centered design practices and the Unified Theory of Acceptance and Use of Technology (UTAUT) to field a successful pilot project.
Modelling on parallel computers: Subchannel analysis on advanced computer architectures

Heat removal in light water nuclear reactor cores involves turbulent two-phase flow parallel to small diameter fuel rods. This situation results in flow which is highly three-dimensional, and accurate modelling is essential to the design and safety analysis of nuclear reactor systems. The present work is part of an ongoing effort in the Nuclear Engineering Department at North Carolina State University to evaluate the use of advanced computer architectures for nuclear engineering problems including neutronics and thermal-hydraulics. The work presented here concentrates on the solution of the seven-banded block-tridiagonal linear systems arising from the modelling of multi-phase flow in fuel rod bundles.
Glia maturation factor (GMF) interacts with Arp2/3 complex in a nucleotide state-dependent manner.

Abstract Glia maturation factor (GMF) is a member of the actin-depolymerizing factor (ADF)/cofilin family. ADF/cofilin promotes disassembly of aged actin filaments, whereas GMF interacts specifically with Arp2/3 complex at branch junctions and promotes debranching. A distinguishing feature of ADF/cofilin is that it binds tighter to ADP-bound than to ATP-bound monomeric or filamentous actin. The interaction is also regulated by phosphorylation at Ser-3 of mammalian cofilin, which inhibits binding to actin. However, it is unknown whether these two factors play a role in the interaction of GMF with Arp2/3 complex. Here we show using isothermal titration calorimetry that mammalian GMF has very low affinity for ATP-bound Arp2/3 complex but binds ADP-bound Arp2/3 complex with 0.7 μm affinity. The phosphomimetic mutation S2E in GMF inhibits this interaction. GMF does not bind monomeric ATP- or ADP-actin, confirming its specificity for Arp2/3 complex. We further show that mammalian Arp2/3 complex nucleation activated by the WCA region of the nucleation-promoting factor N-WASP is not affected by GMF, whereas nucleation activated by the WCA region of WAVE2 is slightly inhibited at high GMF concentrations. Together, the results suggest that GMF functions by a mechanism similar to that of other ADF/cofilin family members, displaying a preference for ADP-Arp2/3 complex and undergoing inhibition by phosphorylation of a serine residue near the N terminus. Arp2/3 complex nucleation occurs in the ATP state, and nucleotide hydrolysis promotes debranching, suggesting that the higher affinity of GMF for ADP-Arp2/3 complex plays a physiological role by promoting debranching of aged branch junctions without interfering with Arp2/3 complex nucleation.
A HindIII/BglII dystrophin gene polymorphism in the African-American population.

We describe a common dystrophin gene polymorphism in the black population that alters both HindIII and BglII restriction sites.
Volumetric analysis of type B aortic dissections treated with thoracic endovascular aortic repair

Background Type B aortic dissections are being successfully treated by thoracic endovascular aortic repair (TEVAR). Postoperative false lumen patency has been associated with aneurysmal dilatation and rupture of the thoracic aorta, necessitating further intervention. This is the first volumetric analysis of type B aortic dissections comparing patients with and without false lumen thrombosis (FLT) after TEVAR. We hypothesized that a greater increase in postoperative true lumen volume will lead to FLT, and without this change, false lumen patency will result. Methods Preoperative and postoperative computed tomography angiography (CTA) imaging was analyzed using three-dimensional reconstruction to measure the short- and long-axis diameter and cross-sectional area of the true lumen, false lumen, and total aorta. Measurements were taken at 5-cm intervals from the left subclavian artery to the aortic bifurcation. Pre- and postoperative volumetric data were calculated and compared in patients with and without postoperative FLT. Results Between 2006 and 2010, 132 patients underwent thoracic aortic stent grafting. Of these, 31 (23%) had thoracic endografting for type B aortic dissection. Pre- and postoperative CTA images were available for analysis in 23 patients with a mean age of 59 ± 14 years treated for acute, complicated (n = 8, 35%), and chronic (n = 15, 65%) indications. Mean follow-up imaging was 9 months (range, 1-39 months). Thirteen patients (56%) had postoperative FLT and 10 (43%) had persistent false lumen patency. The dissections involved the left subclavian artery (n = 12), visceral arteries (n = 14), renal arteries (n = 16), and iliac arteries (n = 15). The left subclavian artery was intentionally covered in 15 patients (65%). There were no significant differences in age, acute vs chronic dissection, branch vessel involvement, coverage of the left subclavian artery, or distal extent of the endograft between patients with and without postoperative FLT. Patients with postoperative FLT had a significantly smaller preoperative maximum thoracic aortic diameter (5.05 ± 1.0 vs 6.30 ± 1.4 cm; P = .02). Volumetric analysis demonstrated significantly smaller preoperative true lumen volume (141.3 ± 68 vs 230.5 ± 92 cm 3 ; P = .01) in patients with FLT, but no difference in preoperative false lumen volume. Patients with FLT had a significant increase in the volume percentage of the true lumen from 42.7% to 61.7% ( P = .02) after stent graft repair, compared with an increase from 46.7% to 47.7% ( P = .75) in patients with persistent false lumen patency. Conclusions This volumetric study of type B aortic dissection treated with TEVAR suggests that the ability of the endograft to significantly increase the true lumen volume as a percent of the total aorta most accurately predicts postoperative FLT. This is best demonstrated in a nonaneurysmal dissection regardless of timing since dissection.
Titan aerosols: Optical properties and vertical distribution

An analysis of Titan's solar phase variation as a function of wavelength together with the continuum geometric albedo makes it possible to set limits on the real part of the refractive index and on the average particle size of the aerosol component of Titan's atmosphere of between about 1.5 and 2.0 and between 0.20 microns and about 0.35 microns, respectively. If the real part of the refractive index is known the average particle size can be determined to within a few percent, and varies inversely with the real part of the refractive index. Using this information in a two-layer model of a methane-aerosol atmosphere and comparing the result with Titan's visible and near-infrared methane spectrum leads to the conclusion that the top layer of Titan's atmosphere contains 0.01 km atm of methane and 2.5 extinction optical depths of aerosol, while the data are consistent with a bottom layer containing 2.2 km atm of methane and about 7.5 aerosol optical depths for a real part of the refractive index equal to 1.7 and an average particle size of 0.25 microns.
HIV vaccine design and the neutralizing antibody problem

Eliciting broadly neutralizing antibodies to human immunodeficiency virus could bring closer the goal of a successful AIDS vaccine. Here the International AIDS Vaccine Initiative Neutralizing Antibody Consortium discusses current approaches to overcome the problems faced.
Review of photon interaction cross section data in the medical and biological context

The probability of a photon (x-ray, gamma-ray, bremsstrahlung, etc) of a given energyE undergoing absorption or scattering when traversing a layer of materialZ can be expressed quantitatively in terms of a linear attenuation coefficient (cm 1 ). Since is dependent on the material's density, (g cm 3 ), which can be variable, the quantity usually tabulated is the mass attenuation coefficient = (cm 2 g 1 ) in which the dependence on the density has been removed. =, in turn, can be obtained as the sum of the different types of possible interactions of photons with atoms of the material. For photon energies below 1 MeV the major interaction processes to be considered are incoherent (Compton) scattering, coherent (Rayleigh) scattering and atomic photoeffect absorption. Above 1 MeV one must also include nuclear-field pair production and atomic-field (triplet) production, and above 5 MeV one in principle should include photonuclear absorption, although the latter is neglected in data tabulations up to the present time. This review includes a selective history of measurements and theory relating to = from the turn of the century up to the present time, and is intended to provide a basis for further calculations and critical tabulations of photon cross section data, particularly as required by users in radiation medicine and biology. The mass energy-absorption coefficient en= is also briefly discussed.
Mechanical characterization of small shale samples subjected to fluid exposure using the inclined direct shear testing device

Abstract The mechanical strength, elastic moduli, and other properties of shale are known to be highly sensitive to any variation in pore fluid content and pore fluid chemical composition. To date, all existing rock mechanics testing procedures and studies attempting to quantitatively quantify these changes employ standard methods and techniques, i.e., shale testing under hydrostatic confinement, triaxial tests, or direct shear tests, which require very long fluid circulation time due to the intrinsic low hydraulic permeability and low solute diffusivity of shale rocks and large sample size recommended by these conventional methods. Moreover, standard-size samples for conventional rock testing methods are not always available, and the use of non-conventional size samples is sometimes required. In this work, shale testing and results on rock sample the size and shape of a stack of a few pennies are presented. The inclined direct shear test, an innovative patent-pending testing method for small and thin rock specimens, has been developed to facilitate mechanical strength characterization under variable confining pressure, with tested material exposed to different fluids at any desired exposure time, while dynamic elastic moduli can be simultaneously monitored as functions of applied stress state. This device has been compared to standard triaxial test with excellent results. Practical applications using the inclined direct shear testing device (IDSTD TM ) for three shale rocks of different natures are also presented herein.
Polarization dependence of magnetic x-ray scattering.

We calculate the polarization dependence of the x-ray scattering cross section, including magnetic terms, using the Poincar\'e representation for the polarization. General expressions are given for the polarization dependence of the cross section of the pure magnetic scattering and of the interference between charge and magnetic scattering, and for the polarization of the scattered beam in both cases. These expressions are compared to the equivalent results for magnetic neutron scattering. The general results are then specialized to several typical cases, including the scattering of linearly and circularly polarized radiation from spiral, uniaxially modulated, and ferromagnetic structures. It is shown that detailed magnetic-structure determinations are possible using synchrotron radiation. It is further demonstrated that the orbital- and spin-angular-momentum contributions of both ferromagnets and antiferromagnets may be separately measured in a variety of simple geometries. It is found that, although the efficiency is very low, linearly polarized radiation can be completely converted to circular polarization by scattering from a magnetic spiral. Finally, it is shown that, in addition to the interference between charge and magnetic scattering, there is an interference involving the spin- and orbital-angular-momentum scattering, which can couple moments in different spatial directions.
Designing Analog MOS Circuits at Berkeley in the Mid-70s

One often reads of cases in which the confluence of several factors, key among them the presence of a core of driven individuals, attracts other motivated people and leads to a happy situation characterized by enthusiasm and creativity, where "sparks fly". Examples can be found in many fields, from physics (e.g., University of Gottingen, Germany, in the 1920s) to music (e.g., Louisville Orchestra, 1950s). In engineering, one of the best examples of this can be found in the Integrated Circuits Lab at the University of California, Berkeley, in the early-to-mid-70s and beyond.
Mitochondrial modification and respiratory deficiency in the yeast cell caused by cadmium poisoning.

Abstract Cells of Fleischmann bakers' yeast were grown in standard nutrient broth and in broth to which cobalt, or cadmium, or thallium, had been added. The cells were fixed by glutaradehyde-permanganate and sectioned. Electron microscopy showed that ( a ) the endoplasmic reticulum was fixed well in cells grown in cobalt or cadmium, but the endoplasmic reticulum was not fixed in cells grown in normal or thallium broth; ( b ) the cristate mitochondria were normal in all cells except those grown in cadmium. No cristae were visible in the “cristate” mitochondria of cells grown in cadmium broth; ( c ) a large fraction of the cells recovered from cadmium broth were respiratory-deficient; ( d ) thallic oxide was present in the cristate mitochondria of cells recovered from thallium broth.
Transforming signs to phase distributions in quantum simulations.

A method is developed which speeds up averaging in quantum simulations where minus signs cause difficulties. A Langevin equation method in conjunction with a replication algorithm is used enabling one to average over a continuously varying complex number. Instead of ensemble averaging this number directly, the phase of the complex number is followed over time. The method is illustrated in some simple cases where the answers obtained can be compared to exact results, and also compared to conventional averaging procedures which converge orders of magnitude slower than this method. Limitations of this method are also described.
Animated visualization of a high resolution color three dimensional digital computer model of the whole human head.

Abstract The interactive visualization of animated images through a computerized three dimensional (3D) full color model of an unstained cadaveric human head is presented. Serial full color images were taken of the blockface of a cryomicrotomed frozen human head every 200 μm. From this series of images a three dimensional digital model with a resultant pixel resolution of 200 μm 3 was created on a UNIX workstation. Using this database, resampled images were computed along orthogonal axes and written sequentially to a write-once-read-many times (WORM) videodisc unit. Playback of this customized videodisc dataset provides animations of the digitally reconstructed slices and 3D reconstructed surface models. An interactive interface to the animated sequences is provided through a PC based tutorial package. This tutorial program is able to access videodisc frames to display animations and labeled still images in a software window to illustrate various neuroanatomic topics. The technique of animation as applied to this high resolution 3D model provides insight into complex spatial relationships and has great potential in research and as a teaching tool in the neurosciences.
Remote real-time library instruction via cable television

Abstract In the fall semester of 1996, the University of Michigan experimented with distance education via the University's cable television network (UMTV). UMTV supplied a mechanism for high-quality, low-cost delivery of real-time remote communication. Through this mechanism, librarians provided distance education to students in the classroom at their point of need, without disturbing the flow of instruction.
Optimization of an immobilized-cell biocatalyst for production of 4-cyanopentanoic acid

Optimization of microbial cell immobilization, catalyst specific activity, and volumetric productivity were required for scale-up of the nitrilase-catalyzed hydrolysis of 2-methylglutaronitrile to ...
Continuum theory of lipid bilayer electrostatics.

In order to address the concerns about the applicability of the continuum theory of lipid bilayers, we generalize it by including a film with uniaxial dielectric properties representing the polar head groups of the lipid molecules. As a function of the in-plane dielectric constant \( \kappa_{{\Vert}}^{}\) of this film, we encounter a sequence of different phases. For low values of \( \kappa_{{\Vert}}^{}\) , transmembrane pores have aqueous cores, ions are repelled by the bilayer, and the ion permeability of the bilayer is independent of the ion radius as in the existing theory. For increasing \( \kappa_{{\Vert}}^{}\) , a threshold is reached --of the order of the dielectric constant of water-- beyond which ions are attracted to the lipid bilayer by generic polarization attraction, transmembrane pores collapse, and the ion permeability becomes sensitively dependent on the ion radius, results that are more consistent with experimental and numerical studies of the interaction of ions with neutral lipid bilayers. At even higher values of \( \kappa_{{\Vert}}^{}\) , the ion/pore complexes are predicted to condense in the form of extended arrays. The generalized continuum theory can be tested quantitatively by studies of the ion permeability as a function of salt concentration and co-surfactant concentration.