cssi/SciSciGPT-SciSciNet huggingface dataset:
Low-Frequency Dielectric Dispersion from Ion Permeability of Membranes

Low-frequency dielectric behavior of membrane/electrolyte systems was studied with artificial membranes made from thin plastic films and NaCl electrolyte of various concentrations. A low-frequency dielectric dispersion or relaxation, which is associated with membrane pores and membrane permeability, was observed and investigated. A qualitative explanation is proposed. Membrane structure characteristics, such as thickness, pore size, and number, were found to affect significantly the low-frequency dielectric dispersion, which indicates some potential applications for low-frequency dielectric measurements in membrane- or tissue-related areas.
Towards a secure EPR: cultural and educational issues

The broader adoption of the EPR in healthcare settings has brought with it much greater attention to the significant issues regarding security, confidentiality and privacy of healthcare information. The economic, social and political impact of these issues is also of major concern. In this paper, it is suggested that the application of contemporary evolutionary game theory has high utility for understanding the actual behaviour of stakeholders in such settings. Contemporary evolutionary game theory can explain the effects of cultural norms, institutional policies and economics on behavior. I also suggest that contemporary evolutionary game theory is sufficiently robust as to be useful in the rational design of a policy to encourage certain socially desired behaviour in this area.
Thermal imaging to detect physiological indicators of stress in humans

Real-time, stand-off sensing of human subjects to detect emotional state would be valuable in many defense, security and medical scenarios. We are developing a multimodal sensor platform that incorporates high-resolution electro-optical and mid-wave infrared (MWIR) cameras and a millimeter-wave radar system to identify individuals who are psychologically stressed. Recent experiments have aimed to: 1) assess responses to physical versus psychological stressors; 2) examine the impact of topical skin products on thermal signatures; and 3) evaluate the fidelity of vital signs extracted from thermal imagery and radar signatures. Registered image and sensor data were collected as subjects (n=32) performed mental and physical tasks. In each image, the face was segmented into 29 non-overlapping segments based on fiducial points automatically output by our facial feature tracker. Image features were defined that facilitated discrimination between psychological and physical stress states. To test the ability to intentionally mask thermal responses indicative of anxiety or fear, subjects applied one of four topical skin products to one half of their face before performing tasks. Finally, we evaluated the performance of two non-contact techniques to detect respiration and heart rate: chest displacement extracted from the radar signal and temperature fluctuations at the nose tip and regions near superficial arteries to detect respiration and heart rates, respectively, extracted from the MWIR imagery. Our results are very satisfactory: classification of physical versus psychological stressors is repeatedly greater than 90%, thermal masking was almost always ineffective, and accurate heart and respiration rates are detectable in both thermal and radar signatures.
Effect of preoperative delay on prognosis for patients with early stage non-small cell lung cancer.

Abstract Objective: Screening for lung cancer will discover many nodules of indeterminate pathology. Observation has the theoretic risk of permitting dissemination of a localized cancer and worsening prognosis, whereas immediate evaluation of benign conditions generates morbidity and cost. This study was conducted to assess the effect of delay in surgical intervention on survival for patients with early stage non-small cell lung cancer. Methods: Records for patients with resected pathologic stage I and II non-small cell lung cancer (1989-1999) were abstracted for patient age, race, sex, medical history, date of presentation, date and type of surgical treatment, pathologic stage, and date of death or last follow-up. Kaplan-Meier survival analysis was performed to test for the effect of delay (time from presentation to surgical intervention) on survival. Results: Eighty-four patients were identified. Median age was 66 years, median preoperative interval was 82 days (range, 1-641 days), and median follow-up was 3.3 years (range, 5 days-11.9 years). Median survival was 3.7 years. Overall 5-year survival was 40%; disease-specific 5-year survival was 63%. Log-rank analysis of the effect of delay on overall survival generated a P value of.54, with an estimated hazard ratio for a 90-day delay of 1.06 (95% confidence interval, 0.87-1.30). Conclusions: For this population, we were unable to detect a significant effect of delay on prognosis. Although these results suggest that the risk of judicious observation of indeterminate pulmonary nodules might be low, the 95% confidence interval is broad. Larger sample sizes are needed to reach definitive conclusions. J Thorac Cardiovasc Surg 2003;125:108-14
Gastrointestinal helminths of free-ranging Florida panthers (Puma concolor coryi) and the efficacy of the current anthelmintic treatment protocol.

Thirty-five Florida panthers (Puma concolor coryi [Bangs, 1899]) collected from six counties in southern Florida between 1978 and 2003 were examined at necropsy for gastrointestinal helminths. The panthers were placed into two groups: 1) treated with anthelmintics (n=17), and 2) untreated (n=18). Nine species of helminths (one trematode, six nematodes, and two cestodes) were identified in the untreated panthers. The most prevalent helminths were Alaria marcianae (LaRue, 1917) (100%), Spirometra mansonoides (Mueller, 1935) (91%), and Ancylostoma pluridentatum (Alessandrini, 1905) (89%). Ancylostoma caninum (Ercolani, 1859) is reported from the Florida panther for the first time. The intensities of helminths with prevalences >10% did not differ between untreated panthers collected in 1978–1983 and 1996–2003. Treated panthers had helminth faunas similar to those of untreated panthers. The current anthelmintic treatment being used reduced the intensity of both A. marcianae and A. pluridentatum in panthers ≤6 ...
Vesicle-associated protein-A is differentially expressed during intestinal smooth muscle cell differentiation.

Gastrointestinal (GI) smooth muscle diseases represent a major health concern affecting in excess of 2 million people each year. Little is currently known regarding the molecular mechanisms controlling either normal or pathogenic GI smooth muscle development. In an effort to identify the specific gene products responsible for modulating GI smooth muscle cell (SMC) differentiation, we performed differential display on distinct intestinal SMC (ISMC) phenotypes. This analysis identified over 40 unique transcripts that appeared to be differentially expressed in distinct SMC phenotypes. One such transcript that appeared to be preferentially expressed in immature smooth muscle myocytes was identified as vesicle-associated membrane protein, associated protein A (VAP-A). Northern blot analysis confirmed that VAP-A was expressed threefold higher in immature smooth muscle myocytes when compared with both smooth muscle myoblasts and mature smooth muscle myocytes. VAP-A mRNA was differentially expressed during normal rat development and showed peak levels of expression in the intestine during late embryogenesis and early neonatal development. These observations provide the first evidence that VAP-A–mediated membrane trafficking may play an important role in modulating ISMC differentiation. Developmental Dynamics 228:11–20, 2003. © 2003 Wiley-Liss, Inc.
Measurement of Clathrate Hydrates via Raman Spectroscopy

Raman spectra of clathrate hydrate guest molecules are presented for three known structures (I (sI), II (sII), and H (sH)) in the following systems: CH4 (sI), CO2 (sI), C3H8 (sII), CH4 + CO2 (sI), CD4 + C3H8 (sII), CH4 + N2 (sI), CH4 + THF-d8 (sII), and CH4 + C7D14 (sH). Relative occupancy of CH4 in the large and small cavities of sI were determined by deconvoluting the ν1 symmetric bands, resulting in hydration numbers of 6.04 ± 0.03. The frequency of the ν1 bands for CH4 in structures I, II, and H differ statistically, so that Raman spectroscopy is a potential tool to identify hydrate crystal structure. Hydrate guest compositions were also measured for two vapor compositions of the CH4 + CO2 system, and they compared favorably with predictions. The large cavities were measured to be almost fully occupied by CH4 and CO2, whereas only a small fraction of the small cavities are occupied by CH4. No CO2 was found in the small cavities. Hydration numbers from 7.27 to 7.45 were calculated for the mixed hydrate.
Measurement of focus and spherical aberration of an electron microscope objective lens.

The displacement between a bright field image and its corresponding dark field image is a measure of both spherical aberration and defocus of the electron microscope objective lens. By measuring the displacements of two image pairs corresponding to two different lattice planes, it is possible to calculate the spherical aberration of a magnetic lens to within ±3% if wave length and magnification are well known. The comparison of experimental results obtained by this technique with the value obtained from a conventional spherical aberration calculation using the distribution of magnetic field over the objective lens shows remarkable accordance. The instrumental astigmatism must be compensated, voltage axis alignment must be carefully made, and one must use a spatially coherent beam for this measurement. The dark field/bright field technique is generally less accurate than the optical diffraction method for focus assessment; however, the optical diffraction method is applicable only to a thin, weak phase object such as carbon film, whereas the displacement method can be used on any substrate. This displacement technique is independent of any phase shift on scattering; thus a combination of the displacement technique with the diffractogram method, which is dependent on the phase shift for scattering, can be used to evaluate the phase shift of the diffracted wave relative to the undiffracted wave.
Nanocrystals as Model Systems for Pressure-Induced Structural Phase Transitions

An understanding of first-order pressure-induced structural transitions is relevant to many research areas in geological and planetary sciences because it involves the study of materials exposed to high pressures. For example, solid-solid transitions in silicates are responsible for the seismic discontinuities in the earth’s mantle (Chudinovskikh and Boehler 2001) and may play a role in plate tectonics and deep earthquakes (Kirby et al. 1991). In geological applications, models of structural transition kinetics simulate rock formation taking place over millions of years (Shekar and Rajan 2001). Despite their importance in earth science applications, the microscopic processes of solid-solid phase transitions are difficult to study in the bulk solid for several reasons (Putnis 1992). In extended solids, the transformation nucleates at defects, which are present at equilibrium even in the highest quality crystals. As a transformed region of the crystal grows larger, mechanical forces generate new defects, which in turn act as new nucleation sites. The difficulties in bulk are compounded by the irreversibility of the kinetics, which depends strongly on the preparation of the sample and its history. The study of first-order phase transitions can be greatly simplified in nanocrystal systems because small crystals can behave as single structural domains and reproducibly cycle through multiple transitions (Wickham et al. 2000). To illustrate the advantages of the simple kinetics in nanoscale systems in exploring fundamental questions of structural phase transitions, this chapter focuses on the CdSe nanocrystal system. Nanocrystalline solid-solid transitions in geologically relevant material such as Fe2O3 nanocrystals are also now being studied (Rockenberger et al. 1999), and a comparable understanding of these materials is a current research goal. The CdSe nanocrystals are a particularly well-controlled and characterized test system (Tolbert et al. 1995). The nanocrystals consist of hundreds to thousands of covalently bonded atoms, synthesized as nearly …
The spectrum of power from wind turbines

The power spectral density of the output of wind turbines provides information on the character of fluctuations in turbine output. Here both 1-second and 1-hour samples are used to estimate the power spectrum of several wind farms. The measured output power is found to follow a Kolmogorov spectrum over more than four orders of magnitude, from 30 s to 2.6 days. This result is in sharp contrast to the only previous study covering long time periods, published 50 years ago. The spectrum defines the character of fill-in power that must be provided to compensate for wind's fluctuations when wind is deployed at large scale. Installing enough linear ramp rate generation (such as a gas generator) to fill in fast fluctuations with amplitudes of 1% of the maximum fluctuation would oversize the fill-in generation capacity by a factor of two for slower fluctuations, greatly increasing capital costs. A wind system that incorporates batteries, fuel cells, supercapacitors, or other fast-ramp-rate energy storage systems would match fluctuations much better, and can provide an economic route for deployment of energy storage systems when renewable portfolio standards require large amounts of intermittent renewable generating sources.
Mechanism of Hg-C Protonolysis in the Organomercurial Lyase MerB

Demethylation is a key reaction in global mercury cycling. The bacterial organomercurial lyase, MerB, catalyzes the demethylation of a wide range of organomercurials via Hg-C protonolysis. Two strictly conserved cysteine residues in the active site are required for catalysis, but the source of the catalytic proton and the detailed reaction mechanism have not been determined. Here, the two major proposed reaction mechanisms of MerB are investigated and compared using hybrid density functional theory calculations. A model of the active site was constructed from an X-ray crystal structure of the Hg(II)-bound MerB product complex. Stationary point structures and energies characterized for the Hg-C protonolysis of methylmercury rule out the direct protonation mechanism in which a cysteine residue delivers the catalytic proton directly to the organic leaving group. Instead, the calculations support a two-step mechanism in which Cys96 or Cys159 first donates a proton to Asp99, enabling coordination of two thiolates with R-Hg(II). At the rate-limiting transition state, Asp99 protonates the nascent carbanion in a trigonal planar, bis thiol-ligated R-Hg(II) species to cleave the Hg-C bond and release the hydrocarbon product. Reactions with two other substrates, vinylmercury and cis-2-butenyl-2-mercury, were also modeled, and the computed activation barriers for all three organomercurial substrates reproduce the trend in the experimentally observed enzymatic reaction rates. Analysis of atomic charges in the rate-limiting transition state structure using Natural Population Analysis shows that MerB lowers the activation free energy in the Hg-C protonolysis reaction by redistributing electron density into the leaving group and away from the catalytic proton.
The Rescorla-Wagner model: losses in associative strength in compound conditioned stimuli.

Conducted 3 experiments with a total of 82 male albino Holtzman rats. Results demonstrate that compound CSs highly conditioned in isolation lost conditioned response strength when compound CS-UCS pairings were given. This loss in conditioned responding was a positive function of the number of compound CS-UCS pairings and was greater for the more salient stimulus. Finally, if a previously neutral stimulus was compounded with 2 previously conditioned cues, the neutral stimulus could acquire conditioned inhibitory properties with only compound CS-UCS pairings. Results provide support for some aspects of R. A. Rescorla and A. R. Wagner's (see PA, Vol 49:6348) general model of Pavlovian conditioning. (PsycINFO Database Record (c) 2006 APA, all rights reserved)
Fluorogenic Peptide Substrates for Serine and Threonine Phosphatases

A new fluorescent assay for Ser/Thr protein phosphatases has been developed. Hydrolysis of a phosphoSer residue liberates the Ser hydroxyl group, which induces a cyclization reaction on the N-terminal carbamate and releases a fluorescent reporter. Sequence selectivity is observed using several peptide substrates against alkaline phosphatase (ALP), bacteriophage λ protein phosphatase (λ-PPase), and vaccinia H1 related phosphatase (VHR). These studies suggest that the assay could be a useful tool for profiling the substrate specificities of medicinally important phosphatases.
NLM video search

In this demo, we will demonstrate usage of NLM Video Search, open-source software which facilitates the dissemination of video content by combining traditional web video playback controls with on-demand seeking using text selected from a corresponding transcript (see Figure 1). NLM Video Search has been implemented in NLM's Fedora-based digital repository, which provides preservation and access to a growing number of rare, historical films and digitized texts.
Biogenesis of Iron-Sulfur Clusters in Photosystem I HOLO-NfuA FROM THE CYANOBACTERIUM SYNECHOCOCCUS SP. PCC 7002 RAPIDLY AND EFFICIENTLY TRANSFERS [4Fe-4S] CLUSTERS TO APO-PsaC IN VITRO

The NfuA protein has been postulated to act as a scaffolding protein in the biogenesis of photosystem (PS) I and other iron-sulfur (Fe/S) proteins in cyanobacteria and chloroplasts. To determine the properties of NfuA, recombinant NfuA from Synechococcus sp. PCC 7002 was overproduced and purified. In vitro reconstituted NfuA contained oxygen- and EDTA-labile Fe/S cluster(s), which had EPR properties consistent with [4Fe-4S] clusters. After reconstitution with 57Fe2+, Mossbauer studies of NfuA showed a broad quadrupole doublet that confirmed the presence of [4Fe-4S]2+ clusters. Native gel electrophoresis under anoxic conditions and chemical cross-linking showed that holo-NfuA forms dimers and tetramers harboring Fe/S cluster(s). Combined with iron and sulfide analyses, the results indicated that one [4Fe-4S] cluster was bound per NfuA dimer. Fe/S cluster transfer from holo-NfuA to apo-PsaC of PS I was studied by reconstitution of PS I complexes using P700-FX core complexes, PsaD, apo-PsaC, and holo-NfuA. Electron transfer measurements by time-resolved optical spectroscopy showed that holo-NfuA rapidly and efficiently transferred [4Fe-4S] clusters to PsaC in a reaction that required contact between the two proteins. The NfuA-reconstituted PS I complexes had typical charge recombination kinetics from [FA/FB]- to P700+ and light-induced low-temperature EPR spectra. These results establish that cyanobacterial NfuA can act as a scaffolding protein for the insertion of [4Fe-4S] clusters into PsaC of PS I in vitro.
The Transport/Phosphorylation ofN,N′-Diacetylchitobiose in Escherichia coli CHARACTERIZATION OF PHOSPHO-IIBChb AND OF A POTENTIAL TRANSITION STATE ANALOGUE IN THE PHOSPHOTRANSFER REACTION BETWEEN THE PROTEINS IIAChb AND IIBChb

Abstract Enzyme II permeases of the phosphoenolpyruvate:glycose phosphotransferase system comprise one to five separately encoded polypeptides, but most contain similar domains (IIA, IIB, and IIC). The phosphoryl group is transferred from one domain to another, with histidine as the phosphoryl acceptor in IIA and cysteine as the acceptor in certain IIB domains. IIBChb is a phosphocarrier in the uptake/phosphorylation of the chitin disaccharide, (GlcNAc)2 by Escherichia coli and is unusual because it is separately encoded and soluble. Both the crystal and solution structures of a IIBChb mutant (C10S) have been reported. In the present studies, homogeneous phospho-IIBChb was isolated, and the phosphoryl-Cys linkage was established by 31P NMR spectroscopy. Rate constants for the hydrolysis of phospho-IIBChb plotted versuspH gave the same shape peak reported for the model compound, butyl thiophosphate, but was shifted about 4 pH units. Evidence is presented for a stable complex between homogeneous Cys10SerIIBChb (which cannot be phosphorylated) and phospho-IIAChb, but not with IIAChb. The complex (a tetramer (3)) contains equimolar quantities of the two proteins and has been chemically cross-linked. It appears to be an analogue of the transition state complex in the reaction: phospho-IIAChb + IIBChb ↔ IIAChb+ phospho-IIBChb. This is apparently the first report of the isolation of a transition state analogue in a protein-protein phosphotransfer reaction.
Halide effects in the hydrolysis reactions of (+/-)-7beta, 8alpha-dihydroxy-9alpha,10alpha-epoxy-7,8,9,10-tetrahydrobenzo- [a]pyrene.

Rates of reaction of (+/-)-7beta,8alpha-dihydroxy-9alpha, 10alpha-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (DE-2) have been determined in 1:9 dioxane-water solutions containing 1.0 M KCl, 0.5 M KBr, and 0.1 M NaI over the pH range 4-13. These pH-rate profiles are more complicated than those for reaction of DE-2 in 0.2 M NaClO4 solutions and are interpreted in part by mechanisms in which halide ion attacks the diol epoxide as a nucleophile at intermediate pH, resulting in the formation of a trans-halohydrin. Reaction of DE-2 in these halide solutions at pH 12, the rate of reaction of DE-2 increases due to a second-order reaction of HO- with DE-2.
Classical mnemonic approach for obtaining hydrogenic expectation values of r P

A recent paper by Drake and Swainson [Phys. Rev. A 42, 1123 (1990)] presents a recursion relation that generates a set of coefficients needed to obtain general closed-form expressions for hydrogenic expectation values for ${\mathit{r}}^{\mathit{P}}$. By combining this recursion relation with an earlier semiclassical formulation of this calculation [J. Phys. B 14, 1373 (1981)], it is shown that the correct expectation values can also be obtained by a simple substitution of prescribed angular momentum operators into the classical Kepler formula, which provides a transparent connection to the correspondence limit.
G Protein Activation: A Protein Unfolding Event?

Ric-8A, is a guanine nucleotide exchange factor for the alpha subunits of class i, q and 13 heterotrimeric G proteins. The biochemical activity of Ric-8A is analogous to that of G protein-coupled receptors (GPCRs), in that it activates Gα by catalyzing the exchange of GDP for GTP at the Gα guanine nucleotide binding site. Unlike GPCRs, Ric-8A acts on Gα•GDP monomers, rather than G protein heterotrimers composed of Gα•GDP and Gβγ. Ric-8A is required to support asymmetric cell division in C. elegans, Drosophila and mouse. Beyond its putative regulatory functions, Ric-8 is essential for Gα biogenesis and membrane localization, and inhibits ubiquitination and degradation of Gα. We have used several biophysical techniques, notably heteronuclear NMR, hydrogen-deuterium exchange, double electron-electron resonance, and Forster resonance energy transfer to characterize the spatial dimensions and kinetics of structural changes that occur in Gαi1 upon binding to Ric-8A, an event that is accompanied by GDP release. Ric-8A induces large inter-domain rearrangements in Gαi1, together with a globally dynamic state in which the nucleotide-binding Ras-like domain in particular appears have diminished tertiary structure. It appears that Ric-8A catalyzes nucleotide release by inducing or stabilizing a structurally heterogeneous, partially unfolded state of Gα.
Infant negative affect and maternal interactive behavior during the still-face procedure: the moderating role of adult attachment states of mind

The current study examined associations between attachment state of mind measured prenatally (N = 259) and maternal behavior in the reunion episode of the still-face procedure when infants were six months of age both as a main effect and in conjunction with infant negative affect. Using a dimensional approach to adult attachment measurement, dismissing and preoccupied states of mind were negatively associated with maternal sensitivity, and each correlated with distinct parenting behaviors. Positive associations were found between dismissing states of mind and maternal monitoring and preoccupied states of mind and maternal withdraw. Maternal preoccupation moderated associations between infant negative affect and maternal intrusive, withdrawn, and monitoring behaviors, supporting the notion that maternal attachment influences parenting behavior via a modulatory process in which infant distress cues are selectively filtered and responded to. Analyses using a traditional AAI scale and classification approach also provided evidence for distinct parenting behavior correlates of insecure adult attachment representations. The importance of measuring global and stylistic differences in maternal behavior in contexts which allow for the activation of the entire range of infant affective states is discussed.
Standing the test of time.

In 1967, Dr. Thomas Killip and Dr. John Kimball [(1)][1] reported their experience with a novel construct called the coronary care unit to cluster and care for patients with suspected acute myocardial infarction (MI). “To provide a clinical estimate of the severity of myocardial derangement,”
On supersaturation spectrum and size distributions of cloud condensation nuclei

The supersaturation spectra of cloud condensation nuclei (CCN) are sometimes S-shaped and always asymptotically approach a limiting value as supersaturation becomes more than several percent. Such a complex shape can correspond to a bell-shaped size distribution of sub-micron aerosols. We found that an exponential expression N = N0 (1-exp[−B SK]) fits measured supersaturation spectra better than the commonly used power law expression N = C SK, where N is the number concentration of CCN at the supersaturation S, N0 is the total number concentration of CCN, B, C and K are empirical coefficients. The exponential expression and the power law are related. For example, at S ∼ 0%, the exponential expression reduces to the power law, with C ∼ N0B. The derived size distribution from the exponential expression agrees closely with measured size distributions for laboratory salts, but not for aerosols in polluted airmasses. The disagreement in polluted airmasses suggests that CCN have complex physiochemistry.
Federal R&D Reductions, Market Share, and Aerospace Information Usage

Reductions in federally funded research have a rippling effect over the entire aerospace industry. The decline in federal R&D spending in aerospace in recent years coincides with declines in U.S. aerospace market share. One of the lesser-understood factors in the declining U.S. market share may be the differing way and intensity with which the U.S. and its competitors approach another trend, the increasing availability of large amounts of aerospace research information on the World Wide Web. The U.S. has been a pioneer in making research information available in electronic form, and the international community has long been a heavy consumer of that information. In essence, the U.S. contributes to the research efforts of its competitors thus contributing to foreign aerospace consortiums efforts to gain market share in the aerospace industry. This may be a cautionary note to the U.S. aerospace industry to consider the use of R&D output in its own development and strategy because the foreign competition is using the U.S. scientific and technical literature.
Evaluation of High-Fidelity Hearing Aids

An essential building block for any high-fidelity hearing aid is an amplifier-transducer-coupling combination that does not audibly degrade the sound. that is, provides high-fidelity sound production as judged by someone with normal hearing. To demonstrate that such a combination is possible, two binaural pairs of hearing aids were assembled using available hearing aid transducers and electronic components, one pair of Over-The-Ear hearing aids with 8-kHz bandwidth and one pair of In-The-Ear hearing aids with 16-kHz bandwidth. Objective insertion-gain measurements on these aids, Obtained with a KEMAR manikin in a diffuse sound field, revealed a frequency-response accuracy comparable to that available in expensive high-fidelity loundspeakers. Subjective fidelity ratings obtain from three groups of ]listeners judging prerecorder A-B-A comparisons (made from equalized eardrum-position microphones in a KEMAR manikin) produced a similar conclusion. We conclude that the important question for hearing aid resear...
Antibiotic selection for the treatment of infectious complications of implant-based breast reconstruction.

Background Infection requiring explantation remains the most devastating complication associated with implant-based breast reconstruction. There are many treatment algorithms to prevent reconstructive failure in face of infection using both oral and intravenous antibiotics. In the absence of patient-specific culture data, antibiotic selection is generally directed toward broad-spectrum coverage based on historical data. We hypothesize that reviewing our institution's microbiology data obtained from explanted implant-based breast reconstructions would provide a rational basis for antibiotic selection in the future. Methods A retrospective review of 902 consecutive immediate implant-based breast reconstructions at a single institution from November 2007 to May 2011 was conducted. Implant reconstructions requiring explantation or drainage by interventional radiology were identified. Patient demographics, implant characteristics, presence of skin necrosis, microbiological data, and outcomes were reviewed. Results Forty-three (4.76%) implant reconstructions requiring explantation or drainage by interventional radiology met the inclusion criteria for this study. Five patients (11.6%) had round, smooth silicone implants, and 36 (88.4%) had textured tissue expanders. Twenty-six implants were explanted because of infection; 3, because of exposure from skin necrosis; and 11, because of the combination of flap necrosis and infection; and 1, secondarily because of cancer invasion into the skin. Reconstruction was salvaged in 21 breasts (51.2%): 12 (57.1%) by implant reconstruction, 5 (23.8%) by pedicled latissimus dorsi flaps, and 4 (19.1%) with a microvascular free flap. Thirty explants had microbiology data available. The most common organism isolated was Staphylococcus epidermidis (10), followed by methicillin-sensitive Staphylococcus aureus (5), Serratia marcescens (5), Pseudomonas aeruginosa (4), enterococcus (3), Escherichia coli (2), Enterobacter (2), group B streptococcus (1), and Morganella morganii (1). Forty percent of the organisms were resistant to cefazolin; however, 86% were sensitive to gentamicin, 80% were sensitive to Levaquin, and 63% were sensitive to ciprofloxacin. Conclusions Infection associated with implant-based breast reconstructions continues to threaten explantation and reconstructive failure. Based on our microbiological data, initial cellulitis amenable to oral antibiotics should be treated with oral fluoroquinolones as a first-line treatment. If this regimen fails, intravenous imipenem or gentamicin and vancomycin should be initiated. Obviously, clinical judgment regarding specific patient risk factors and compliance should play a role in decision making, but these data provide an evidence-based rationale for first-line oral antibiotic selection.
Surface wave tomography

Surface waves are now being used by several groups to map lateral heterogeneity [Nakanishi and Anderson, 1982, 1983, 1984a, b; Woodhouse and Dziewonski, 1984] and anisotropy [Tanimoto and Anderson, 1984a, b; Nataf et al. 1984] of the upper mantle on a global basis. The method involves measuring the phase and/or group velocity over hundreds of small arcs and long arcs connecting earthquakes and seismic stations. These averages are then converted to three-dimensional images of the seismic velocity structure, and, hence, this is a form of tomography. The large amount of data processing required is made feasible by the existance of long-period digital seismic networks including IDA (International Deployment of Accelerometers), SRO (Seismic Research Observatories), and GDSN (Global Digital Seismic Network). These instruments are operated by a variety of university and government groups including University of California, San Diego, U.S. Geological Survey, D.A.R.P.A., and U.S. Department of Energy with the cooperation of many countries. The global coverage is still very sparse compared to the analog W.W.S.S.N. (World Wide Standardized Seismic Network), but preliminary results are very encouraging. The possibility of an expanded global digital network of broadband seismic stations is now being pursued actively by the United States and several other countries. Because of the sparseness of the present network, mantle structure can only be mapped with fairly low resolving power. Only features with half wavelength of the order of 2,000 km can be detected.
Large-scale conformational dynamics of the HIV-1 integrase core domain and its catalytic loop mutants.

HIV-1 integrase is one of the three essential enzymes required for viral replication and has great potential as a novel target for anti-HIV drugs. Although tremendous efforts have been devoted to understanding this protein, the conformation of the catalytic core domain around the active site, particularly the catalytic loop overhanging the active site, is still not well characterized by experimental methods due to its high degree of flexibility. Recent studies have suggested that this conformational dynamics is directly correlated with enzymatic activity, but the details of this dynamics is not known. In this study, we conducted a series of extended-time molecular dynamics simulations and locally enhanced sampling simulations of the wild-type and three loop hinge mutants to investigate the conformational dynamics of the core domain. A combined total of >480 ns of simulation data was collected which allowed us to study the conformational changes that were not possible to observe in the previously reported short-time molecular dynamics simulations. Among the main findings are a major conformational change (>20 A) in the catalytic loop, which revealed a gatinglike dynamics, and a transient intraloop structure, which provided a rationale for the mutational effects of several residues on the loop including Q148, P145, and Y143. Further, clustering analyses have identified seven major conformational states of the wild-type catalytic loop. Their implications for catalytic function and ligand interaction are discussed. The findings reported here provide a detailed view of the active site conformational dynamics and should be useful for structure-based inhibitor design for integrase.
A convex approach to inverse optimal control and its application to modeling human locomotion

Inverse optimal control is the problem of computing a cost function that would have resulted in an observed sequence of decisions. The standard formulation of this problem assumes that decisions are optimal and tries to minimize the difference between what was observed and what would have been observed given a candidate cost function. We assume instead that decisions are only approximately optimal and try to minimize the extent to which observed decisions violate first-order necessary conditions for optimality. For a discrete-time optimal control system with a cost function that is a linear combination of known basis functions, this formulation leads to an efficient method of solution as an unconstrained least-squares problem. We apply this approach to both simulated and experimental data to obtain a simple model of human walking trajectories. This model might subsequently be used either for control of a humanoid robot or for predicting human motion when moving a robot through crowded areas.
Eliciting Self-Explanations Improves Children's Performance on a Field-Based Map Skills Task

Abstract To investigate children's ability to translate between the environment and an abstract representation, fourth graders were asked to indicate the location of colored flags by placing similarly colored stickers on a map. In the explaining condition, students wrote down what clues they had used; in the baseline condition, they placed stickers without explanation. The explaining students significantly outperformed the baseline students, especially with respect to egregious errors indicative of failure to understand basic representational correspondence. The hypothesized interpretation is that children who generated explanations were more likely to notice and then correct discrepancies between their answers in progress and the referent space and that they did so by activating existing spatial and symbolic competencies.
Chemical and biological assessment of two offshore drilling sites in the Alaskan Arctic.

A retrospective chemical and biological study was carried out in Camden Bay, Alaskan Beaufort Sea, where single exploratory oil wells were drilled at two sites more than two decades ago. Barium from discharged drilling mud was present in sediments at concentrations as high as 14%, ∼200 times above background, with significantly higher concentrations of Ba, but not other metals, within 250 m of the drilling site versus reference stations. Elevated concentrations of Cr, Cu, Hg and Pb were found only at two stations within 25 m of one drilling site. Concentrations of total polycyclic aromatic hydrocarbons (TPAH) were not significantly different at reference versus drilling-site stations; however, TPAH were elevated in Ba-rich layers from naturally occurring perylene in ancient formation cuttings. Infaunal biomass and species abundance were not significantly different at reference versus drilling-site stations; infauna were less diverse at drilling-site stations. Our assessment showed that discharges from single wells within large areas caused minimal long-term, adverse impacts to the benthic ecosystem.
5-Chloro-2-thienyl-β-dialkylaminoethyl Ketones and Related Compou47

The syntheses of ten β-amino ketones of the type RCOCH2CH2-NR'2 o HCI from 5-chloro-2-acetylthiophene and 4-(5-chloro-2-thienyl)-3-buten-2-one by the Man-nich reaction are described. Some of these bases were found to possess in vitro activity against certain bacteria.
Complicating the ‘logic of design’

Abstract A ‘logic of design’ was outlined by March in 1976. Since then it has gained wide acceptance among designers and recently has been used in several knowledge-based systems of design. This paper makes a suggestion for extending the model by taking into consideration the logical nature of the laws in the argument form. This focus on the logical nature of laws brings out interesting and subtle differences in the inference process which are lost in the current analysis. It also results in some interesting complications. It means that it is no longer adequate to talk of the three phases of design — performance prediction, knowledge acquisition, and design generation — in the simple categories of deduction, induction and abduction, respectively. In particular, it means that performance prediction is not necessarily (or even usually) a deductive inference.
The spectrum of SY M2+1

Abstract We apply supersymmetric discrete light-cone quantization (SDLCQ) to the study of supersymmetric Yang-Mills theory on R × S 1 × S 1 . One of the compact directions is chosen to be light-like and the other to be space-like. Since the SDLCQ regularization explicitly preserves supersymmetry, this theory is totally finite, and thus we can solve for bound-state wave functions and masses numerically without renormalizing. We present an overview of all the massive states of this theory, and we see that the spectrum divides into two distinct and disjoint sectors. In one sector the SDLCQ approximation is only valid up to intermediate coupling. There we find a well defined and well behaved set of states, and we present a detailed analysis of these states and their properties. In the other sector, which contains a completely different set of states, we find that while these state have a well defined spectrum their masses grow with the transverse momentum cutoff.
Laser Abutiow for the Introduction of Solid Metals into an Inductively Coupled Plasma

Abstract The direct introduction of solid samples into an inductively coupled plasma (ICP) has been studied using ablation of metals by a focused XeCl excimer laser. The laser pulses form a very energetic microplasma at the metal surface from which the ablated species are carried into a stream of argon and are detected using a gated integrator/boxcar averager. This method is applied to the analysis of Ni and Cr in stainless steels.
Penetration of nonintegral magnetic flux through a domain-wall bend in time-reversal symmetry broken superconductors

It has been proposed that the superconductivity of Sr${}_{2}$RuO${}_{4}$ is characterized by pairing that is unconventional and, furthermore, spontaneously breaks time-reversal symmetry. However, one of the key expected consequences, viz., that the ground state should exhibit chiral-charge currents localized near the boundaries of the sample, has not been observed, to date. We explore an alternative implication of time-reversal symmetry breaking: the existence of walls between domains of opposing chirality. Via a general phenomenological approach, we derive an effective description of the superconductivity in terms of the relevant topological variables (i.e., domain walls and vortices). Hence, by specializing to the in-plane rotationally invariant limit, we show that a domain wall that is translationally invariant along the $z$ axis and includes an isolated bend through an angle $\ensuremath{\Theta}$ is accompanied by a nonintegral magnetic bend flux of $[(\ensuremath{\Theta}/\ensuremath{\pi})+n]{\ensuremath{\Phi}}_{0}$, with integral $n$, that penetrates the superconductor, localized near the bend. We generalize this result to the situation in which gauge transformations and rotations about the $z$ axis are degenerate transformations of the chiral superconducting order. These results are independent of the magnitude of chiral-charge currents that are predicted to flow along the core of domain walls. On the basis of the specialized result and its generalization, we note that any observation of localized, nonintegral flux penetrating a $z$-axis surface (e.g., via scanned-probe magnetic imaging) could potentially be interpreted in terms of the presence of bent walls between domains of opposing chirality, and hence is suggestive of the existence of time-reversal symmetry breaking superconductivity.
Security of international civil aviation: The role of ICAO

Abstract The International Civil Aviation Organization in the last twenty years has marshaled support of the overwhelming majority of its 150 member states in developing security programs and establishing a legal framework of international cooperation against terrorism in international aviation. The Tokyo Convention of 1963 establishes jurisdiction over offenses while an aircraft is in flight and grants a wide spectrum of powers to the aircraft commander to restrain a passenger. The Hague Convention of 1970 obliges states to punish the unlawful seizure of aircraft with severe penalties and to either extradite the offender or try him. The Montreal Convention of 1971 establishes a system of suppression of acts against aircraft, covering mostly acts on the ground that might endanger an aircraft in flight, and requires states to take practicable measures to prevent such offenses. In the past few years the number of countries adhering to these pacts and instituting improved security measures has increased sign...
6βHydroxy cortisol: A Noninvasive Indicator of Enzyme Induction

We measured urinary 6 beta-hydroxycortisol (6 beta OHF) excretion in normal children and in children receiving anticonvulsant therapy with phenobarbital or diphenylhydantoin, 6 beta OHF excretion increased 4- to 7-fold during anticonvulsant therapy. The marked increase in the ratios of 5 beta OHF to 17-hydroxycorticosteroid and 6 beta OHF to free cortisol suggests that the measured increase in urinary 6 beta OHF may serve as an index of induction of the microsomal mixed function oxidase system. This noninvasive approach allows rapid assessment of the effects of drugs and foreign compounds on microsomal hydroxylation of cortisol. This convenient probe can be applied, with particular ease, to further studies in children in whom characterization of the effects of drugs and xenobiotic compounds on hepatic hydroxylation is of interest.
Deep hypothermic arrest and left thoracotomy for repair of difficult thoracic aneurysms

Seven patients with complex thoracic aortic aneurysms were operated on using profound hypothermia and circulatory arrest through a left thoracotomy. Three patients had false aneurysms, 2 had large aneurysms precluding access for proximal control, 1 patient had had previous hemiarch replacement, and 1 patient had a thoracoabdominal aneurysm. All patients were cooled on partial cardiopulmonary bypass until the electroencephalogram was isoelectric (approximately 15 degrees C rectal temperature). Circulatory arrest times ranged from 7 to 56 minutes (median, 34 minutes). There was one death due to cardiac failure, and paraplegia developed in 1 patient. The 6 survivors are otherwise well at a median of 12 months postoperatively. Hypothermia and circulatory arrest is an invaluable technique for the treatment of complex aortic aneurysms requiring left thoracotomy for resection. The techniques employed are described and the indications for their use are discussed.
High-order QAM transmission for spectrally-efficient and high-capacity transport

High-order QAM offers the high spectral efficiency and high capacity. PDM-64QAM with single-carrier frequency-division-multiplexing (SC-FDM) enhanced by pilot-tone-based phase noise compensation is proposed and shown to achieve high-capacity transport with 400Gb/s-class high speed channels.
Transient conductivity of some semiconductors and plasmas

The decay function of transient conductivity for some cases of semiconductors and plasmas is numerically computed. The results will be useful in analyzing experimental data on conductivity dispersion and to determine the nature of the dispersion mechanism.