cssi/SciSciGPT-SciSciNet huggingface dataset:
Observing the Unobservable? Modeling Coronal Cavity Densities

Prominence cavities in coronal helmet streamers are readily detectable in white-light coronagraph images, yet their interpretation may be complicated by projection effects. In order to determine a cavity's density structure, it is essential to quantify the contribution of noncavity features along the line of sight. We model the coronal cavity as an axisymmetric torus that encircles the Sun at constant latitude and fit it to observations of a white-light cavity observed by the Mauna Loa Solar Observatory (MLSO) MK4 coronagraph from 2006 January 25 to 30. We demonstrate that spurious noncavity contributions (including departures from axisymmetry) are minimal enough to be incorporated in a density analysis as conservatively estimated uncertainties in the data. We calculate a radial density profile for cavity material and for the surrounding helmet streamer (which we refer to as the "cavity rim") and find that the cavity density is depleted by a maximum of 40% compared to the surrounding helmet streamer at low altitudes (1.18 R☉) but is consistently higher (double or more) than in coronal holes. We also find that the relative density depletion between cavity and surrounding helmet decreases as a function of height. We show that both increased temperature in the cavity relative to the surrounding helmet streamer and a magnetic flux rope configuration might lead to such a flattened density profile. Finally, our model provides general observational guidelines that can be used to determine when a cavity is sufficiently unobstructed to be a good candidate for plasma diagnostics.
The International Pediatric Adrenocortical Tumor Registry initiative: Contributions to clinical, biological, and treatment advances in pediatric adrenocortical tumors

Adrenocortical tumor (ACT), a rare tumor with a heterogeneous presentation, incompletely understood pathogenesis, and generally poor prognosis, occurs in 1-2 people per million and is even more uncommon in the pediatric population. Such rare cancers are a challenge to clinical practice. Exchange of experience, information, and data on rare cancers is lacking, and outcomes for these rare cancers could be improved through the establishment of an international registry. The establishment of the International Pediatric Adrenocortical Tumor Registry (IPACTR) in 1990 by the St. Jude Children's Research Hospital International Outreach Program offered a new opportunity to collect clinical and laboratory features, treatment practices, and outcome data for children with ACT, research this disease, and systematically investigate how to improve patient outcomes. These efforts will improve the availability of information for both patients and the medical community.
Metallic nanostructure formation limited by the surface hydrogen on silicon.

Constant miniaturization of electronic devices and interfaces needed to make them functional requires an understanding of the initial stages of metal growth at the molecular level. The use of metal−organic precursors for metal deposition allows for some control of the deposition process, but the ligands of these precursor molecules often pose substantial contamination problems. One of the ways to alleviate the contamination problem with common copper deposition precursors, such as copper(I) (hexafluoroacetylacetonato) vinyltrimethylsilane, Cu(hfac)VTMS, is a gas-phase reduction with molecular hydrogen. Here we present an alternative method to copper film and nanostructure growth using the well-defined silicon surface. Nearly ideal hydrogen termination of silicon single-crystalline substrates achievable by modern surface modification methods provides a limited supply of a reducing agent at the surface during the initial stages of metal deposition. Spectroscopic evidence shows that the Cu(hfac) fragment is ...
Observations of elastic instabilities in lid-driven cavity flow

Abstract An experimental investigation of the lid-driven cavity flow of a Boger fluid is completed in order to verify the scaling theory for the aspect ratio dependence of the critical conditions for elastic instability as proposed by Grillet, Yang, Khomami and Shaqfeh [A.M. Grillet, B. Yang, B. Khomami, E.S.G. Shaqfeh, Modeling of viscoelastic lid driven cavity flow using finite element simulations, J. Non-Newtonian Fluid Mech. 88 (1999) 99–131]. Measurements of the critical conditions in shallow cavities show that the critical Weissenberg number and the wavelength of the instability are independent of the cavity aspect ratio, Λ, for aspect ratios less than unity. Our experiments also demonstrate the importance of polymer concentration on the stability of cavity flows. The effect of concentration is included in new scaling arguments based on those developed for Taylor–Couette and Dean flow elastic instabilities; thus, we successfully describe experimental results at different polymer concentrations. Further experiments are described using flow-induced birefringence to measure the polymer stresses prior to the onset of instability in order to investigate the role of the downstream stress boundary layer in the stability of the flow. Measurements taken in three aspect ratios provide evidence that, for shallow cavities, the polymer stress emanating from the downstream corner can reach the region of curved streamlines at the bottom of the cavity, and possibly result in an elastic instability. This is consistent with the scaling theory proposed by Grillet et al. [A.M. Grillet, B. Yang, B. Khomami, E.S.G. Shaqfeh, Modeling of viscoelastic lid driven cavity flow using finite element simulations, J. Non-Newtoniam Fluid Mech. 88 (1999) 99–131].
Barriers to, and Strategies for, Starting a Long Acting Injection Clinic in a Community Mental Health Center

As many as 50% of patients with schizophrenia do not take oral antipsychotic medications as prescribed, yet long acting injections are rarely utilized. Community agencies that serve this population are often over-burdened and poorly funded. There are negative attitudes on the part of both physicians and consumers about injections. Transportation and logistics are often problematic. We describe the unique opportunity provided by the need for bi-weekly or monthly injections to establish a recovery-oriented group around injection visits. Our approach discusses methods and resources to help overcome some of the common barriers by establishing advocates within the agency, establishing necessary infrastructure, providing education for consumers, providers, and staff, sharing information about successful outcomes with clinic staff and working through billing issues. We also recommend public advocacy on the part of the clinic and consumers to work with state funding sources to change regulations that may limit appropriate clinical care.
Thermodynamic studies on the binding of adenosine diphosphate and calcium to beef cardiac myosin

Abstract Thermodynamic quantities for the binding of MgADP, CaADP and Ca 2+ to purified beef cardiac myosin have been determined by flow calorimetry at 25°C and by equilibrium dialysis at 4°C in 0.5 M KCl, 20 mM Tris-HCl (pH 7.5). About 1.65 ± 0.15 mol MgADP and 1.9 ± 0.1 mol CaADP were bound per mol myosin. Free energies of binding of MgADP and CaADP were −6.7 and −5.7 kcal/mol, respectively. Enthalpies for binding of MgADP and CaADP were about −12.5 and −19.0 kcal/mol, respectively. Furthermore, there were 1.8 ± 0.2 mol high affinity Ca 2+ binding sites per mol myosin with an affinity constant of about 10 5 M −1 . The enthalpy of Ca 2+ binding was about zero. It is concluded that CaADP binds to cardiac myosin with a much greater negative enthalpy than MgADP. Also, the free energy of MgADP binding to cardiac myosin is similar to values reported for skeletal myosin. However, the enthalpy of binding is much less negative than the value obtained for skeletal myosin by Kodama and Woledge (J. Biol. Chem. (1976) 251, 7499–7503). The latter results suggest a subtle difference in the nucleotide binding sites of these myosins.
A fully automated method for clot based coagulation panels using an MCA Multistat Centrifugal Analyzer

Abstract Small modifications of the commercially available software of the I.L. Multistat Centrifugal Analyzer (MCA) enabled us to evaluate clot based prothrombin times (PT), activated partial thromboplast in times (APTT) and thrombin times (TT) simultaneously within one run. This imparted a great deal of flexibility to this procedure in that batches and/or panels of clot based and other types of turbidimetric tests can be performed concurrently in any combination. The PT and TT by this turbidimetric procedure correlated very well with those of the Fibrometer in normal specimens as well as in a wide variety of coagulation defects. The turbidimetric APTT procedure, however, often produced clotting times longer than those achieved with the Fibrometer. The discrepancy between the Fibrometer and turbidimetric APTT procedures was shown to be the consequence of greater sensitivity of the latter to detect low concentrations of heparin, elevated fibrinogen split products and mild factor deficiencies. The available clot based procedures are suitable for use in detecting specific factor deficiencies and the presence of coagulation inhibitors.
The Antarctic cryptoendolithic microbial ecosystem as a model for studying microbes in shale and coal

Abstract In Antarctica, there exists a complete microbial ecosystem that lives hidden within the pore spaces of sandstone (cryptoendolithic). Studying microbes within this solid matrix has presented certain technical problems which have been overcome. This has allowed studies to be conducted that have shown the effects of the physical and chemical environment on growth and metabolism of the microbes in these rocks. Similar microbial communites have recently been discovered that can exist within the solid matrix of shale and coal. Even though the community and environment are different from the antarctic microbes, many of the methods and hypotheses regarding their existence are the same. Answers to questions relating how and why these microbes exist in shale and coal may have important implications for coal desulfurization, or degradation of the shale matrix to release hydrocarbons.
Parameter Sensitivity Analysis Applied to Modeling Transient Enhanced Diffusion and Activation of Boron in Silicon

Transient enhanced diffusion (TED) during annealing of implanted boron in silicon greatly impedes the formation of junctions that are sufficiently shallow for advanced complementary metal oxide semiconductor devices. For reasons of cost and efficiency in process development, detailed modeling of TED is often used for designing annealing procedures. However, because model validation depends primarily on fitting experimental dopant profiles, and because realistic models contain dozens of parameters that are poorly known, development of a unique set of rate parameters with true predictive capability has proven elusive. Here we have employed formal parameter sensitivity analysis by the finite difference method to show that the activation energies most critical to know accurately are those for interstitial boron diffusion, kick-in, and dissociation of the (B s - Si i ) + complex to liberate either interstitial B (kick-out) or Si. Maximum likelihood estimation is also applied to the literature for interstitial cluster formation to determine a most likely set of activation energies for cluster dissociation.
Molecular Distinction Between Atypical Ductal Hyperplasia and Ductal Carcinoma In Situ

: The increasing use of screening mammography has led to an increased detection of high-risk proliferative breast disease and premalignant breast lesions. This change in the pattern of disease presentation has highlighted the existing limitations in the understanding of the biology of these entities. It has also emphasized the significance of deficiencies involved in the morphologic recognition of the spectrum of changes that occur in precursor lesions. The criteria for morphologic distinction between atypical ductal hyperplasia (ADH) and low-grade ductal carcinoma in situ (DCIS) have remained controversial. There are also difficulties in subclassification of DCIS. To resolve some of these issues, attempts have been made to use new and emerging technologies to study these borderline breast lesions and to distinguish between ADH and DCIS. This article discusses the significance of the newly recognized biomarkers and emphasizes the need for further prospective studies.
Modeling Short Term Interest Rates: A Comparison of Methodologies

The celebrated Taylor rule methodology has established that the decisions made by the Federal Open Market Committee concerning possible changes in short term interest rates reflected in Fed funds are influenced by deviations from a desired level of inflation and from potential output. The Taylor rule determines the future interest rate and is one among several methodologies than can be used to predict future short term interest rates. In this study we use four competing methodologies that model the behavior of short term interest rates. These methodologies are: time series, Taylor, econometric and neural network. Using monthly data from 1958 to the end of 2005 we distinguish between sample and out-of-sample sets to train, evaluate, and compare the models' effectiveness.
Mechanism of laser induced solubility reduction of dental enamel

Several studies in our laboratories have demonstrated that CO2 laser treatment of dental enamel can inhibit subsequent caries-like progression from 10-75 percent compared to controls. The present study tested the hypothesis that laser radiation at specific wavelengths is absorbed by the mineral, converted efficiently to heat at the surface, causing thermal decomposition of the carbonated apatite enamel crystals to a less soluble form. Samples of enamel 5 X 5 mm were examined before and after laser irradiation by specular reflectance FTIR. Sample surfaces were irradiated by pulsed CO2 laser at 9.3, 9.6, 10.3 or 10.6 micrometers , 100 microsecond(s) pulse duration, 25 pulses per spot, with fluences of 0-6 J/cm2. In separate experiments surface temperatures were measured dependent, and fluence dependent, with total loss occurring with 9.6 micrometers irradiation occurred at 4 J/cm2. Optimum inhibition of caries progression following 9.6 micrometers irradiation occurred at 4 J/cm2. We conclude that irradiation of dental enamel by specific wavelengths and fluences of CO2 laser light alters the chemical composition of the crystals, decomposing the CO3 component, thereby markedly reducing the reactivity.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Ethical preferences, risk aversion, and taxpayer behavior

Abstract Conventional models of taxpayer behavior largely overlook the ethical aspect of the income-reporting problem, and are generally unable to explain observed compliance rates unless risk aversion is severely exaggerated. As a correction, this paper modifies the standard model to include a moral preference parameter. Aggregate time series data on self-employed taxpayers are used to calibrate the model and impute the implicit monetary value of ethical conduct. The results suggest that tax evasion induces remorse-based disutility comparable to a tax on unreported income at rates averaging approximately 39%, though this measure of morality appears to have declined during the 1980s.
No evidence for the reversal of adrenal failure after hematopoietic cell transplantation in X-linked adrenoleukodystrophy.

No evidence for the reversal of adrenal failure after hematopoietic cell transplantation in X-linked adrenoleukodystrophy
Rapid Assembly of Multifunctional Thin Film Sensors for Wind Turbine Blade Monitoring

Wind is a competitive, clean, and fast-growing renewable energy industry. However, in order for wind to compete with fossil fuel-based energies, it is necessary to achieve lower cost of energy. One way is to reduce operations and maintenance costs by integrating structural health monitoring (SHM) systems with wind turbines. It has been found that the fiber-reinforced polymer (FRP) composite-based wind blades are susceptible to damage (e.g., cracks, debonding, and impact). Damage is typically invisible to the naked eye and can propagate rapidly to cause sudden failure. This work presents a new SHM approach using embedded thin film sensors for detecting damage in FRP-based wind blades. While previous studies have shown that carbon nanotube-based thin films can be incorporated with FRPs for sensing, this study further investigates their electromechanical properties. First, a unique spray fabrication approach was employed so that films can be assembled on a low cost basis and can be deposited onto any substrate or structure. Second, the electrical properties of films subjected to post-fabrication thermal annealing were compared. Finally, freestanding films were prepared and subjected to uniaxial tensile cyclic loading while their resistivity was measured simultaneously. The results showed that these films were piezoresistive.
Hepatic microsomal ethanol-oxidizing system: solubilization, isolation, and characterization.

Abstract The solubilization and subsequent separation of the hepatic microsomal ethanol-oxidizing system from alcohol dehydrogenase and catalase activities by DEAE-cellulose column chromatography is described. Absence of alcohol dehydrogenase in the column eluates exhibiting microsomal ethanol-oxidizing system activity was demonstrated by the failure of NAD + to promote ethanol oxidation at pH 9.6. Differentiation of the microsomal ethanol-oxidizing system from alcohol dehydrogenase was further shown by the apparent K m for ethanol (7.2 m m , insensitivity of the microsomal ethanol-oxidizing system to the alcohol dehydrogenase inhibitor pyrazole (0.1 m m ) and by the failure of added alcohol dehydrogenase to increase the ethanol oxidation. Absence of catalatic activity in these fractions was demonstrated by spectrophotometric and polarographic assay. Differentiation of the microsomal ethanol-oxidizing system from the peroxidatic activity of catalase was shown by the apparent K m for oxygen (8.3 μ m ), insensitivity of the microsomal ethanol-oxidizing system to the catalase inhibitors azide and cyanide, and by the lack of a H 2 O 2 -generating system (glucose-glucose oxidase) to sustain ethanol oxidation in the eluates. The oxidation of ethanol to acetaldehyde by the alcohol dehydrogenase- and catalase-free fractions required NADPH and oxygen and was inhibited by CO. The column eluates showing microsomal ethanol-oxidizing system activity contained cytochrome P -450, NADPH-cytochrome c reductase, and phospholipids and also metabolized aminopyrine, benzphetamine, and aniline.
Three-dimensional photoacoustic tomography of finger joint: from phantom experiment to in vivo study

In this study, we present phantom experiments and in-vivo human examination to evaluate the possibility of threedimensional (3D) photoacoustic imaging of the finger joints in a spherical scanning geometry. The phantom results show that 1mm thick "cartilage" can be accurately differentiated from the "bones" with a 1 MHz transducer. Results based on in-vivo finger joint study show that major anatomical features in the joint can be imaged, and the cartilages associated with the joint can be differentiated well from the phalanx. The results shown in this paper suggest that 3D PAT in a spherical scanning geometry has the potential to be used for early diagnosis of joint diseases
Dynamical Properties of Induced-Moment Systems

The low-temperature excitation spectrum for ferro- and antiferromagnets with large crystalline-field splittings is derived using the Bogoliubov transformation. Specific application is made to those systems where the single-ion ground state is a singlet and the magnetization of the coupled ions arises from the Van Vleck temperature-independent susceptibility. ${\mathrm{Pr}}^{3+}$ and ${\mathrm{Eu}}^{3+}$ in cubic and hexagonal environments are used as examples. The specific heat, magnetization, and nuclear-nuclear coupling are computed for both the ordered and paramagnetic regimes. The results in the paramagnetic limit display a characteristic energy gap $\ensuremath{\Delta}{[1\ensuremath{-}\ensuremath{\alpha}(\frac{K}{\ensuremath{\Delta}})]}^{\frac{1}{2}}$, where $\ensuremath{\Delta}$ is the crystalline field splitting (or, in ${\mathrm{Eu}}^{3+}$, the spin-orbit splitting) between the ground singlet and first excited state, $K$ is the exchange integral, and $\ensuremath{\alpha}$ is a constant proportional to the Van Vleck temperature-independent susceptibility. In the magnetically ordered state, the same behavior is found for longitudinal excitations in ${\mathrm{Pr}}^{3+}$ and ${\mathrm{Eu}}^{3+}$ salts with a gap equal to ${({\ensuremath{\alpha}}^{2}{K}^{2}\ensuremath{-}{\ensuremath{\Delta}}^{2})}^{\frac{1}{2}}$, while transverse excitations are found to exhibit a linear dispersion law without an apparent gap in the limit of complete isotropy. The phase transition between the paramagnetic and ordered regimes is shown to be of second order. However, the entropy of ordering is shown to be reduced from the usual value $\mathrm{NK}$ $\mathrm{ln}(2S+1)$.
Nanodevice design through the functional abstraction of biological macromolecules

Biologic macromolecules are prefabricated, functional nanocomponents readily incorporated into nanodevices. Semibiologic nanodevice design typically depends on knowledge of specific biomolecules by individual biologist designers, so individual devices seldom take full advantage of available biodiversity and are poorly optimized. Available informational resources (proteomic and genomic databases) were built to reflect evolutionary relationships between organisms, molecules, and biologic systems, and are lacking in their explicit functional properties. This limits their direct utility in nanodevice design. We discuss the need, and possible structure for an information framework that captures the function of biological macromolecules to enable rational nanodevice design and optimization.
Optimal power/performance pipelining for error resilient processors

Timing speculation has been proposed as a technique for maximizing the energy efficiency of processors with minimal loss in performance. A typical implementation of timing speculation involves speculatively reducing the voltage of a processor to a point where errors are possible but rare, and employing an error recovery mechanism to ensure correct functionality. This allows significant energy savings with a small recovery overhead.
Layering algorithm for collision-free traversal using hexagonal self-reconfigurable metamorphic robots

This paper presents an algorithm that deterministically plans the simultaneous, collision-free movement of n hexagonal metamorphic robots (modules) over any contiguous surface composed of modules in a hexagonal grid. A planning stage algorithm identifies narrow passages between surface cells where moving modules will come into contact. After identifying all narrow passages on a surface, our algorithm identifies the cells that can be used to build temporary structures across the entrance to each narrow passage using 1, 2, or 3 modules. The algorithm does not use intermodule message passing at any stage of the traversal, making it suitable for modules with limited communication capabilities. The algorithm maintains optimal spacing between moving modules throughout the traversal. Our current algorithm is an improvement over previous bridging algorithms because the bridging cells are situated such that when they are filled with modules, they do not form narrow passages (pockets) on the surface. In this paper, we also propose a multi-layered technique for finding longer bridges. We discuss the complexity and performance of our algorithms and give an example of the results of simulating them using a discrete event simulator.
Parental grieving after a child dies from cancer: is stress from stem cell transplant a factor?

Aim To investigate psychological distress, family functioning and complicated grieving in parents whose child had died from cancer, and as a function of whether: (a) the deceased child had also received stem cell transplant (SCT) any time during curative treatment; and (b) the place of the child’s death (home or hospital). Design A cross-sectional case-match design. Sample Fifty-six Australian bereaved parents in two groups: 28 whose child had also received SCT, matched with 28 (on deceased patient variables) whose child had not received SCT. Results Parents in the ‘SCT group’ (n=28) reported relatively higher levels of depression, anxiety and stress, and – for those whose child had also died in hospital – a greater likelihood of meeting the criteria for traumatic grief than those parents whose deceased child had not received SCT. There were no significant group differences in family functioning. Conclusion Routine psychosocial screening, especially for families undergoing SCT, may contribute usefully to ...
Osmotic relations of some metazoan parasites.

1. The osmotic behaviour of three parasites in normal and experimental media has been studied with a view to understanding the relationship with their hosts. 2. Angusticaecum sp., a nematode frpm the intestine of the tortoise, is hypertonic in media of very low concentrations (1·1-1·3 % NaCl in tap water), but becomes isotonic in sea water and slightly hypertonic in 50 % sea water. Ligaturing experiments show that its cuticle is permeable to water and probably to salts. 3. Lernaeocera branchialis, a blood-feeding copepod from Gadus spp., is hypotonic to the surrounding sea water so long as it remains attached to its host, its blood showing an osmotic pressure equivalent to 2·O-2·8 % NaCl. Isotonicity with the medium is established when the parasite is excised and kept alive. Hypotonicity of Lernaeocera is probably caused by the low osmotic pressure of the blood of its host (1·443 % NaCl in Gadus pollachius), to which it is permanently attached. 4. Bopyrus squillarum, a blood-sucking isopod from Leander serratus, is isotonic or slightly hypotonic to sea water, the tendency towards hypotonicity being probably the result of the hypotonic nature of the blood of the host. 5. The osmotic properties of Lerpaeocera and Bopyrus would suggest their ability to survive in dilute sea water, a fact which is supported by their occurrence on hosts living in inshore or estuarine habitats.
Analysis of cytokine secretion by melanoma-specific CD4+ T lymphocytes

Although specific antitumor immune reactivity has been documented extensively in CD8+ T cells derived from melanoma patients, relatively little is known about CD4+ T cell responses against melanoma. Tumor-infiltrating lymphocytes (TIL) cultured from metastatic lesions in five patients yielded cytolytic CD8+ T cells with specific activity against autologous and MHC class I-compatible allogeneic melanoma targets. In four of the five cases studied, CD4+ T cells purified from bulk TIL cultures also reacted specifically with autologous melanoma cells, as manifested by the secretion of various cytokines (GM-CSF, TNF-alpha, and IFN-gamma) after a 24 h cocultivation. Cytokine secretion by CD4+ T cells was MHC class II restricted, and proved to be a more reliable indicator of the immunologic reactivity of CD4+ T cells than cytolysis. Three of the four reactive CD4+ TIL failed to recognize allogeneic melanomas, suggesting recognition of Ag with limited expression in the patient population. Cloning such Ags may provide clues to optimizing current antitumor immunization strategies.
His, hers, or ours? Work-to-family spillover, crossover, and family cohesion

Using the contagion model of spillover and crossover, this study examines gender differences in the effects of workplace characteristics (e.g., hours worked in the paid-labor force, job satisfactio...
Effects of calcium on shortening velocity in frog chemically skinned atrial myocytes and in mechanically disrupted ventricular myocardium from rat.

Effects of [Ca2+] on isometric tension and unloaded shortening velocity were characterized in single chemically skinned myocytes from frog atrium and in mechanically disrupted myocardium from rat ventricle. The preparations were attached to a force transducer and piezoelectric translator and were viewed with an inverted microscope to allow continuous monitoring of sarcomere length during mechanical measurements. Unloaded shortening velocity was determined by measuring the time required to take up various amounts of slack imposed at one end of each preparation. Ca2+ sensitivity of isometric tension was assessed as pCa50, i.e., the Ca2+ concentration at which tension was 50% maximal, and was greater for frog atrial myocytes (pCa50 6.17) than for rat ventricular myocytes (pCa50 6.06). This difference in Ca2+ sensitivity may be due to variations in myofibrillar protein isoform composition in the two preparations. Inclusion of caffeine in the activating solutions substantially increased the Ca2+ sensitivity of tension, which may be a manifestation of a direct effect of caffeine on the myofibrillar proteins. Unloaded shortening velocity during maximal activation averaged 4.32 muscle lengths per second in frog atrial myocytes and 4.46 muscle lengths per second in rat ventricular myocytes. When [Ca2+] was reduced, unloaded shortening velocity decreased substantially in both preparations. Possible mechanisms for the effect of Ca2+ on shortening velocity in myocardium include Ca2+ dependence of the rate of ADP dissociation from actomyosin complexes or a shortening-dependent internal load involving structures such as C protein or long-lived myosin cross-bridges.
Observation of Bimolecular Carrier Recombination Dynamics in Close-Packed Films of Colloidal CdSe Nanocrystals

We study the intensity dependence of the photoconductivity in close-packed films of CdSe quantum dots in which the photoconductivity is characterized by a low density of trapped charges. We find that the intensity dependence of the photocurrent is nonlinear, which is indicative of bimolecular charge carrier recombination dynamics. We present a physical model for the intensity dependence of the photocurrent that is used to fit the data and extract a ratio of the density of carriers to the density of trapped charges. As our model predicts, we show that the current vs intensity plot becomes more linear when the carrier density is decreased.
Evaluation of endospore purification methods applied to Bacillus cereus

Research on spore inactivation techniques requires highly pure spore suspensions, but the efficacy of commonly used purification methods has not been systematically compared. By providing this comparison, the present study will help researchers improve the consistency and validity of their experiments. The current study evaluated alternative purification methodologies applied to Bacillus cereus endospores on the basis of criteria of purity, yield, time investment and effect on integrity of spores. The ASTM E2111-00, ethanol, heat shock, daily water washes and lysozyme treatment methods were applied to B. cereus cultures incubated for 3 and 10 days. Purities achieved ranged from 67 to 99% spores as a proportion of total colony forming units in the purified suspension, whereas yields ranged from less than 1 to 39% spores in proportion to total colony forming units of B. cereus culture. TEM images showed that only lysozyme treatment substantially altered spore morphology. Ethanol treatment is optimum for 3-day B. cereus cultures, whereas the ASTM method is most favorable for 10-day-old cultures. Lysozyme treatment is the least attractive purification method because of its large time investment and damage to spores.
Site of intracellular antigen production by myxoviruses.

SummaryThe multiplication cycles of Sendai, mumps, and Newcastle disease viruses were compared with that of influenza A virus in regard to site of antigen production in the cell. Single-cycle infections were followed using fluorescent antibodies prepared from infection-convalescent immune sera shown to contain anti-S and anti-V antibodies. In cells infected with influenza A virus antigen was first detectable in the nucleus and became abundant there by the time antigen appeared in the cytoplasm. In cells infected with Sendai, mumps, or Newcastle disease viruses earliest detectable antigen was found as small granules scattered throughout the cytoplasm. Antigen granules increased in size and number to form large cytoplasmic aggregates and masses. Multiplication of Sendai, mumps, or Newcastle disease viruses did not include production of antigen in the nucleus detectable by fluorescent antibody at any stage of the cycle.
A three-dimensional hybrid stress isoparametric element for the analysis of laminated composite plates

Abstract In view of the increasing interest in using composite materials for aerospace structures, the analysis of laminated composite plates becomes essential. A three-dimensional eight-node hybrid stress finite element method is developed for the analysis of laminated plates. The hybrid stress model is based on the modified complementary energy principle and takes into account the transverse shear deformation effects. The displacement field is interpolated through shape functions and nodal displacements. All three displacement components are assumed to vary linearly through the thickness of each lamina. The stress field is interpolated through assumed stress polynomials with 55 stress parameters for each lamina. All six stresses are included and satisfy the homogeneous equilibrium equations. The validity of the hybrid stress finite element model is determined by comparing the predicted numerical results with the existing three-dimensional elasticity solutions. Excellent accuracy and fast convergence are observed in the numerical results.
Genetic factors associated with loss of the temperature-sensitive phenotype of the influenza A/Alaska/77-ts-1A2 recombinant during growth in vivo.

Abstract The influenza A/Alaska/77-ts-1A2 vaccine candidate strain, which has a 37° shutoff temperature for plaque formation and temperature-sensitive (ts) lesions on the P1 and P3 genes, was administered intranasally to a seronegative child who subsequently remained well. However, starting 7 days after inoculation, A/Alaska/77 virus with a 40° shutoff temperature (ts+) was shed. To determine whether an extragenic suppressor mutation was responsible for this loss of ts phenotype of the vaccine candidate virus, the ts+ isolate was mated with wild-type virus, and ts recombinant progeny were sought. Approximately 25% of the progeny were ts, suggesting that a suppressor mutation was present in the child's ts+ isolate. Each of 62 ts progeny viruses had the ts P3 gene. The extragenic suppressor of this ts gene was localized to the P2 gene. The ts P3 gene of the A/Alaska/77-ts-1A2 recombinant specified a 37–38° shutoff temperature for plaque formation, whereas the ts P3 gene in the ts segregants derived from the ts+ isolate had a 39° shutoff temperature. Hence, the ts P3 gene in the ts+ isolate developed an intragenic mutation affecting its level of temperature sensitivity. In addition, the P3 RNA of the ts+ virus migrated more slowly in polyacrylamide gel than the P3 RNA of its A/Alaska/77-ts-1A2 parent. We failed to isolate ts P1 segregants from the ts+ isolate, indicating that the P1 ts mutation had reverted or undergone intragenic suppression. The ability of ts mutants to escape from their ts phenotype by suppression and other mutations may limit their usefulness in immunoprophylaxis since attenuation of ts mutants of influenza virus appears to be a function of the ts phenotype. Additionally, suppressor mutations provide new opportunities for studying the nature of protein-protein interactions.
When BITs have some bite: The political-economic environment for bilateral investment treaties

Political risk frequently impedes the flow of capital into developing countries. In response, governments often adopt innovative institutions that aim to attract greater flows of international investment and trade by changing the institutional environment and limiting the risk to outside investors. One primary example of this is the Bilateral Investment Treaty (BIT), aimed specifically at increasing the flow of foreign direct investment (FDI) to developing countries. Yet the literature in political science and economics is inconclusive about whether or not BITs do indeed stimulate FDI, and it provides conflicting theoretical reasoning for the claimed connection. This article argues that BITs do attract FDI to developing countries, but the story is a complicated one. Two important factors must be taken into account. First, BITs cannot entirely substitute for an otherwise weak investment environment. Countries must have the necessary domestic institutions in place that interact with BITs to make these international commitments credible and valuable to investors. Second, as the coverage of BITs increases, overall FDI flows to developing countries increase. However, although remaining positive, the marginal effect of a country’s BITs on its own FDI may fall because of heightened competition for FDI from other BIT countries. Using data from 97 countries for 1984–2007, we provide empirical evidence consistent with both of these theoretical claims.
Simulations of ion beams for NDCX-II ☆

Abstract NDCX-II, the second neutralized drift compression experiment, is a moderate energy, high current accelerator designed to drive targets for warm dense matter and IFE-relevant energy coupling studies, and to serve as a testbed for high current accelerator physics. As part of the design process, studies were carried out to assess the sensitivities of the accelerator to errors, and to further optimize the design in concert with the evolving pulsed power engineering. The Warp code was used to carry out detailed simulations in both axisymmetric and full 3-D geometry. Ensembles of simulations were carried out to characterize the effects of errors, such as timing jitter and noise on the accelerator waveforms, noise on the source waveform, and solenoid and source offsets. In some cases, the ensemble studies resulted in better designs, revealing operating points with improved performance and showing possible means for further improvement. These studies also revealed a new non-paraxial effect of the final focus solenoid on the beam, which must be taken into account in designing an optimal final focusing system.
Bronchoscopy in North America: The ACCP Survey

SUMMARY A mail survey of this type, has several inherent drawbacks. First, answers to some of the questions, particularly those pertaining to complication rates, rely on the memory of participants. Second, the wording of certain questions may have imparted different meanings. Third, the format of the questionnaire may have confused some. Fourth, one cannot expect that all questionnaires will be answered fully. Fifth, as indicated by several respondents, several important topics (eg, topical anesthetic agents and mode of their delivery, prophylaxis against infective endocarditis, tracheobronchial stent placement, endobronchial intraluminal radiotherapy) were not included. Many respondents suggested inclusion of these and other questions in future surveys. Nevertheless, in the absence of any survey looking into a large number of bronchoscopy-related practices, mail surveys have the advantage of reflecting nationwide practice rather than results from selected centers, and this report provides some insight into bronchoscopy practices in North America. While the results indicate the present trends in bronchoscopy practices in North America, they do not establish or recommend any standards in bronchoscopy.
Effects of citalopram on worry and brain activation in patients with generalized anxiety disorder

The effects of auditory statements describing a personal worry on brain activation as measured by functional magnetic resonance imaging were examined in patients with generalized anxiety disorder (GAD) before and after anxiety reduction with citalopram. Six patients were imaged while listening to verbal descriptions of a personal worry or a neutral statement before treatment with citalopram and after 7 weeks of treatment. Pre-post drug analyses showed treatment with citalopram reduced self-reported anxiety and reduced BOLD responses to a pathology-specific worry and a neutral stimulus. After treatment, worry sentences, compared to neutral statements, elicit reduced BOLD responses in prefrontal regions, the striatum, insula and paralimbic regions. In addition, contrasts before and after treatment revealed reductions in the differential response that existed between worry and neutral statements. Overall reduction of BOLD response was most prominent during neutral statements, particularly in the left hemisphere. These findings support the clinical impression that GAD patients overreact to both pathology-specific and non-specific cues and that the reduction of anxiety attenuates the response to both types of cues.
Identifying Change Points in a Covariate Effect on Time-to-Event Analysis with Reduced Isotonic Regression

Isotonic regression is a useful tool to investigate the relationship between a quantitative covariate and a time-to-event outcome. The resulting non-parametric model is a monotonic step function of a covariate X and the steps can be viewed as change points in the underlying hazard function. However, when there are too many steps, over-fitting can occur and further reduction is desirable. We propose a reduced isotonic regression approach to allow combination of small neighboring steps that are not statistically significantly different. In this approach, a second stage, the reduction stage, is integrated into the usual monotonic step building algorithm by comparing the adjacent steps using appropriate statistical testing. This is achieved through a modified dynamic programming algorithm. We implemented the approach with the simple exponential distribution and then its extension, the Weibull distribution. Simulation studies are used to investigate the properties of the resulting isotonic functions. We apply this methodology to the Diabetes Control and Complication Trial (DCCT) data set to identify potential change points in the association between HbA1c and the risk of severe hypoglycemia.
Regiospecific, Enantiospecific Total Synthesis of C-19 Methyl Substituted Sarpagine Alkaloids Dihydroperaksine-17-al and Dihydroperaksine

The optically active tetracyclic ketone 8 was converted into the pentacylic core 14 of the C-19 methyl substituted N(a)-H sarpagine and ajmaline alkaloids via a critical haloboration reaction. The ketone 14 was then employed in the total synthesis of 19(S),20(R)-dihydroperaksine-17-al (1) and 19(S),20(R)-dihydroperaksine (2). The key regioselective hydroboration and controlled oxidation-epimerization sequence developed in this approach should provide a general method to functionalize the C(20)-C(21) double bond in the ajmaline-related indole alkaloids.
Tests of Gene‐Environment Interaction for Case‐Parent Triads with General Environmental Exposures

As knowledge of the human genome continues to grow, more progress is being made towards not only identifying the genes involved in disease susceptibility but also in defining the synergistic role genes play with environmental exposures. The detection of gene-environment interactions is important as it can offer clinicians a potential means of intervention. The discovery of interactions relies heavily on powerful statistical methods. We present a test, FBAT-I, that can be used to investigate gene-environment interaction. The test uses the case-parent triad design and protects the statistical inference from potential spurious results due to population admixture.
Life changes as etiologic factors in juvenile rheumatoid arthritis

JUVENILE Rheumatoid Arthritis (JRA or Still's Disease) is a significant disease of children, annually affecting 175,000 (1 in 1,500) children in this country [1]. It cripples more children than any other musculo-skeletal disease and is a major cause of childhood blindness [2]. Great strides have been made in the diagnosis, treatment, and management of JRA, yet its etiology remains obscure. Immunopathy, allergy, infection, trauma, heredity, and psychosocial factors have all been postulated, but no conclusion has been reached. In focusing upon the psychological factors involved, the author agrees with Scotch and Geiger [3] who assume JRA may have "a multiple, rather than a unitary etiology .... The question is not whether social factors 'cause' the disease, but rather whether they contribute to its causation." Although there was and is controversy, JRA is generally regarded as a variant of Rheumatoid Arthritis (RA) [2-5], and despite significant differences in the natural history of the disease [2, 6], the literature concerning both RA and JRA and their relationship to psychosocial factors will be reviewed briefly. A link between psyche and soma in RA has been hypothesized since the 1920's [7-10]. However, no clear cut evidence such as Engel's [11] classic work with ulcerative colitis has emerged. Most investigations have concentrated on personality analysis and behavior patterns. King [7] described the RA patient as shy and socially inadequate, self-sacrificing, overconscientious, depressed, and unable to show hostility. Later, he and Cobb [12] associated RA with men who made less money, had terminated marriages, "worried more", and had fewer children; in women who had less education and more children; and in both sexes where there was incongruity of income and education. Cormier and Wittkower [13] say that RA patients have "difficulty in the usual methods of coping with the environment and with other people, and severe blocking of external expression of emotion with internalization of feeling and autonomic activity." Solomon [14], comparing 16 RA patients with their unaffected siblings by means of psychodrama, noted that no RA showed more anger than the sibling, and only 2 showed as much. He states that "the clearest and most consistent finding related to the masochism, self-sacrifice, and denial of hostility shown by arthritic patients". With Moos [15], he administered the MMPI to patients and siblings and showed that RA's had higher scores on somatic reaction, female masochism, psychological rigidity and moralism, complianee/subserviance, reserve/introversion, and conservatism/security.
Limits to the power conversion efficiency of vertical-cavity surface-emitting lasers

Summary form only given. Reduction of electrical and optical losses in vertical-cavity surface-emitting lasers (VCSELs) through improved design, growth, and fabrication techniques has produced dramatic improvements in power conversion efficiency (PCE). In this paper simple analytical formulae based on realistic linear models are presented for maximum PCE as a function of electrical parameters, material gain coefficients, and optical losses, and optimum values are derived for design variables. The theoretical results are compared with published experimental data for high-efficiency vertical-cavity surface emitting lasers, and a comprehensive figure-of-merit, which relates directly to maximum theoretical PCE is discussed.