cssi/SciSciGPT-SciSciNet huggingface dataset:
HEAT TRANSFER FROM IMMERSED TUBES IN A BAFFLED SLURRY BUBBLE COLUMN

Abstract Heat transfer coefficients have been measured from heat transfer tube bundles simulating heat exchanger configurations and surrounding two-phase and three-phase dispersions in a slurry bubble column. The tube bundles are comprised of a single tube, and five-, seven-, and thirty-seven tubes of 19 mm outer diameter. The Pyrex glass bubble column is 0.305 m internal diameter and 3.30 m tall and is heated electrically by internal heaters to temperatures in the range 298 to 353 K. Air, water and glass beads are used as gas, liquid and solid phases respectively. Heat transfer coefficients are measured for air-water, and air-water-glass bead systems as a function of air velocity up to about 0.3 m/s, and solids concentration up to about 30 weight percent in slurries of glass beads of average diameters 125, 168 and 212 μm at temperatures of 298, 323, 343 and 353 K. The nondimensional correlation available for heat transfer coefficient is also examined and modifications in its form are proposed on the basi...
Productivity and Distribution of Trichoptera Larvae in a Colorado Mountain Stream

From June 1968 to late May, 1969 collections of more than 20,600 immature Trichoptera were made from the St. Vrain River of Colorado. Agapetus sp., Arctopsyche grandis, Brachycentrus americanus, Ecclisomyia maculosa, Hydropsyche sp., Hydropsyche occidentalis, Helicopsyche borealis, Leptocella sp., Neothremma alicia, Rhyacophila acropedes, and Sortosa sp. were taken at eight sites ranging from 1565 to 3200 m in altitude. The Trichoptera of the St. Vrain exhibited a distinct altitudinal zonation with Zone I (1565 m) dominated by Leptocella, Hydropsyche sp., and Helicopsyche borealis; Zone II (1750 to 2350 m) was dominated by Brachycentrus americanus and Hydropsyche occidentalis; Zone III (2350 m) was considered a transitional area. In Zone IV (2650 m) and Zone V (2950 to 3250 m ) Neothremma alicia and Arctopsyche grandis were the most successful genera, respectively. Temperature is proposed as the major variable controlling attitudinal zonation.
A Chi-Square Program for a Microcomputer Using a Tape Unit.

A program utilizing a microcomputer and tape drive is described which requires only the entering of the number of rows and number of columns, plus one-time entry of cell frequencies. Despite some limitations, the usefulness of the program for problems difficult to handle on a calculator and not fully suitable for a large-scale computer has been demonstrated.
Quantum Corrected Monte Carlo Simulation of Semiconductor Devices Using the Effective Conduction-Band Edge Method

In recent years much effort has been devoted to the quantum mechanically corrected Monte Carlo simulation of nano-scale semiconductor devices. The effective potential and the Wigner or the Bohm quantum potential are usually chosen for making such quantum correction. In this study we propose another approach based on the Bohm potential by transforming the density gradient to an effective conduction-band edge gradient. Similar to the effective potential method, this method has the advantage of not being affected by density fluctuations. We have applied this method to the simulation of a double-gate nMOSFET. Results are compared to those obtained from the semi-classical Monte Carlo simulation without the quantum correction.
Insulin-like growth factor-I affects amino compounds in the fluids of the chicken embryo.

The concentration differences of more than 40 amino acids and related compounds in the amniotic fluid, allantoic fluid, and plasma of the chicken embryo are maintained by specific barriers. Since the amniotic and allantoic membranes are not innervated, we proposed that these barriers are controlled by hormones. Specific effects of insulin and prolactin on the amino compounds in the three fluids confirmed this hypothesis and raised the question of the possible role of growth factors. Application of insulin-like growth factor-I (IGF-I) to the chorioallantoic membrane of day 13 chicken embryos caused the following concentration changes in 41 amino compounds measured 1 and 2 h later: (1) in the amniotic fluid, an increase of 40 compounds, regardless of the presence or absence of a concomitant stress effect on these compounds; only NH3 was not affected; (2) in the allantoic fluid, a decrease of reduced glutathione (GSH) and anserine, and an increase of NH3; (3) in the plasma, a decrease of 24 compounds. Within the same time frame, stress caused in the amniotic fluid a drop of the concentration of 29, and an increase of 5, amino compounds; IGF-I reversed the stress effect on all 29 compounds the concentrations of which had dropped and enhanced the stress-induced increase of the other 5 compounds. In the allantoic fluid, stress induced an increase of GSH; IGF-I reversed this effect. In the plasma, stress caused an increase of 9 compounds; IGF-I counteracted the increase in 7 cases. These findings indicate new and unexpected roles of IGF-I in the prenatal regulation of amino compounds.
A Patient With Nasal Valve Compromise

A 45-year-old woman presented with a complaint of nasal airway obstruction and a history of aesthetic rhinoplasty at age 20 years. She had been initially happy with the appearance of her nose, but over time, she felt that her nose had adopted a narrow, “pinched” appearance. She also noted gradually worsening nasal airway obstruction. After a 3-month trial of medical therapy failed, the patient was referred for further evaluation. Physical examination revealedanarrowmiddleone-thirdofhernoseanddeepalar grooves (Figure 1).Anterior rhinoscopyshowedasevereS-shapedseptaldeviation, worse on the left side. Rigid nasal endoscopy revealed narrowingof the internal nasal valves (INVs)bilaterally,with severe collapse on the right side (Figure 2).
An integrated system for planning, navigation and robotic assistance for skull base surgery.

Background We developed an image-guided robot system to provide mechanical assistance for skull base drilling, which is performed to gain access for some neurosurgical interventions, such as tumour resection. The motivation for introducing this robot was to improve safety by preventing the surgeon from accidentally damaging critical neurovascular structures during the drilling procedure.
Observation of self-amplified spontaneous emission in the near-infrared and visible wavelengths

We report evidence of self-amplified spontaneous emission (SASE) at 1064 and 633 nm. To our knowledge, these are the first measurements of SASE at such a short wavelength and employ the smallest period wiggler, 8.8 mm, used to date in a successful SASE experiment. The experiments were performed with the MIT microwiggler at the Accelerator Test Facility at BNL. Single-pass, on-axis microwiggler emissions within a 25 nm bandwidth have been recorded as a function of beam charge and show a clear enhancement over spontaneous emission. For the measurement at 1064 nm, a single micropulse at 34 MeV with a variable charge of 0--1 nC and less than 5 ps full width at half maximum bunch length was passed through the microwiggler and emissions into a limited solid angle and bandwidth, selected by an aperture and interference filter, were focused onto a silicon photodiode. Enhancement of the emissions, from 2 to 6 times the spontaneous emission level, was observed at the highest charges. In addition, we observed SASE gain at a wavelength of 633 nm at a beam energy of 48 MeV, without detailed measurements.
Allopatric Divergence, Secondary Contact, and Genetic Isolation in Wild Yeast Populations

Summary In plants and animals, new biological species clearly have arisen as a byproduct of genetic divergence in allopatry. However, our understanding of the processes that generate new microbial species remains limited [1] despite the large contribution of microbes to the world's biodiversity. A recent hypothesis claims that microbes lack biogeographical divergence because their population sizes are large and their migration rates are presumably high [2, 3]. In recapitulating the classic microbial-ecology dictum that "everything is everywhere, and the environment selects" [4, 5], this hypothesis casts doubt on whether geographic divergence promotes speciation in microbes. To date, its predictions have been tested primarily with data from eubacteria and archaebacteria [6–8]. However, this hypothesis's most important implication is in sexual eukaryotic microbes, where migration and genetic admixture are specifically predicted to inhibit allopatric divergence and speciation [9]. Here, we use nuclear-sequence data from globally distributed natural populations of the yeast Saccharomyces paradoxus to investigate the role of geography in generating diversity in sexual eukaryotic microbes. We show that these populations have undergone allopatric divergence and then secondary contact without genetic admixture. Our data thus support the occurrence of evolutionary processes necessary for allopatric speciation in sexual microbes.
Using radiometric tools to track sediment and phosphorus movement in an agricultural watershed

Summary Increased levels of phosphorus (P) in freshwater systems generally cause eutrophication leading to algal blooms, fish kills, and decreased biodiversity. Point sources have been fairly well characterized; however, non-point sources (NPS), such as agricultural fields, require further study to ascertain the origin and physicochemical forms of P. During a single storm event in June 2008 in a small Wisconsin agricultural watershed (12.4 km2), a comprehensive study was performed to characterize sediment and P transport dynamics. In addition to standard analytical techniques to quantify sediment and P transport, the atmospheric fallout radionuclides (7Be, 210Pbxs, and 137Cs) were employed to determine sediment origin and in-stream transport parameters. Sediments originated primarily from surficial upland soils, or cultivated fields, with minor contributions of resuspended streambed sediments and no discernable stream bank contributions. Sediments were deposited onto the streambed during this event, creating a temporary store, which could be resuspended during subsequent flow events. While for this moderate storm event the stream channels exhibited a short-term depositional behavior they appeared erosional in nature over longer time periods. Particulate-bound P was found to be 33–46% of the total P (TP) transported in the stream channel. The mean dissolved P and TP concentrations at the two stream sites ranged from 0.99 ± 0.32 mg L−1 to 1.14 ± 0.63 mg L−1 and 1.77 ± 0.78 mg L−1 to 1.83 ± 0.78 mg L−1, respectively. During baseflow conditions, the mean dissolved reactive P (DRP) and TP concentrations were quite high, 0.27 ± 0.02 mg L−1 and 0.33 ± 0.04 mg L−1, respectively, exceeding recommended USEPA TP levels (0.08 mg L−1; USEPA, 2000 ) for eutrophication threshold. Overall, significant transport of P in both dissolved and particulate forms occurred during this moderate stormflow event. We assert that improved upland conservation practices are necessary to minimize P export from this agricultural watershed.
Small Area Variations in Health Care Delivery

Health information about total populations is a prerequisite for sound decision-making and planning in the health care field. Experience with a population-based health data system in Vermont reveals that there are wide variations in resource input, utilization of services, and expenditures among neighboring communities. Results show prima facie inequalities in the input of resources that are associated with income transfer from areas of lower expenditure to areas of higher expenditure. Variations in utilization indicate that there is considerable uncertainty about the effectiveness of different levels of aggregate, as well as specific kinds of, health services. Informed choices in the public regulation of the health care sector require knowledge of the relation between medical care systems and the population groups being served, and they should take into account the effect of regulation on equality and effectiveness. When population-based data on small areas are available, decisions to expand hospitals, currently based on institutional pressures, can take into account a community's regional ranking in regard to bed input and utilization rates. Proposals by hospitals for unit price increases and the regulation of the actuarial rate of insurance programs can be evaluated in terms of per capita expenditures and income transfer between geographically defined populations. The PSRO's can evaluate the wide variations in level of services among residents of different communities. Coordinated exercise of the authority vested in these regulatory programs may lead to explicit strategies to deal directly with inequality and uncertainty concerning the effectiveness of health care delivery. Population-based health information systems, because they can provide information on the performance of health care systems and regulatory agencies, are an important step in the development of rational public policy for health.
Expanding to Meet Readers' Needs

This editorial describes how IEEE Security a Privacy has expanded its offerings to more effectively meet readers' needs.
Math Anxiety: An Update

As reported in Overcoming Math Anxiety 1978, 1980, in 600 interviews with college-age and older returning students, Tobias found three significant variables in her subjects' inability to do college...
Human Goodpasture anti-α3(IV)NC1 autoantibodies share structural determinants Rapid Communication

Human Goodpasture anti-α3(IV)NC1 autoantibodies share structural determinants. To examine the structural relationship among autoantibodies produced by individuals with anti-GBM antibody-mediated disease, a polyclonal anti-idiotype directed against human anti-α3(IV)NC1 antibodies was produced and then used to study autoantibodies from other patients. For this purpose, anti-α3(IV)NC1 antibodies (anti-GBM), derived from a single patient (LL) with high titer and typical anti-GBM antibody specificity, were isolated using recombinant α3(IV)NC1-sepharose affinity chromatography. Following hyperimmunization of rabbits with anti-GBM IgG, irrelevant rabbit anti-human IgG antibodies were removed from the antiserum using a human IgG-sepharose column. The rabbit anti-α3(IV)NC1 antibodies (anti-Id GBM) effluent bound to human anti-GBM antibodies, but it did not bind to either normal human IgG or recombinant α3(IV)NC1 protein. The Id-anti-Id interaction was conformationally dependent on intact heavy and light chains of the anti-α3(IV)NC1 antibodies (ELISA and Western blotting). A competitive immunoassay was developed to evaluate structural and potential genetic relationships among anti-α3(IV)NC1 antibodies from different patients. All patients tested (9 of 9) had a substantial fraction (producing > 50% inhibition) of anti-GBM antibodies expressing Id-GBM. The results indicate that shared determinants are expressed by anti-GBM antibodies from different individuals, and they raise the possibility that common genetic elements are used to encode them. These regions are potential targets for design of reagents to regulate autoreactive B cells and/or interfere with pathogenic antibody-GBM interactions, in individuals with anti-GBM antibody mediated diseases.
Capturing Interdependencies and Heterogeneity in the Management of Multifacility Transportation Infrastructure Systems

We present a quadratic programming formulation for the problem of obtaining optimal maintenance and repair policies for multifacility transportation infrastructure systems. The proposed model provides a computationally tractable framework to support decision making, while accounting for economic interdependencies that link the facilities that comprise these systems. To demonstrate the advantages of the proposed model, we present numerical examples that capture economic interdependencies reflecting both costs associated with disruptions/loss of throughput, as well as the benefits associated with coordinating intervention schedules of adjacent facilities to reduce costs associated with resource and personnel delivery. The results illustrate situations where it is optimal to coordinate (synchronize or alternate) interventions for clusters of facilities in transportation systems.
Comparison of the merckoquant 10007 nitrite test strip with conventional reagents in the detection of nitrate reduction by bacteria

Abstract The Merckoquant 10007 nitrite test strip was compared with the conventional test in determining nitrate reduction by bacteria. 659 strains, comprising 83 genera and 283 species, were examined; seven types of nitrate broths were utilized. A 99.24% correlation was observed between the results of the two tests. A 100% correlation was observed when metallic zinc was added to the negative nitrate broths and nitrite test strips to determine if reduction had proceeded past the nitrite stage.
The pyrethroids: Early discovery, recent advances and the future

A brief survey is given of the historical development of some of the more stable synthetic pyrethroids from the starting point of the natural pyrethrins. The main physico-chemical, biological and toxicological properties of the synthetic pyrethroids are outlined as a background for the following papers. The importance of the pyrethroids in modern agricultural practice is stressed and areas of future application and development are discussed.
Push–pull tetraene chromophores derived from dialkylaminophenyl, tetrahydroquinolinyl and julolidinyl moieties: optimization of second-order optical nonlinearity by fine-tuning the strength of electron-donating groups

A series of highly polarizable chromophores 1–3 has been synthesized based on three different types of electron donors, including diethylaminophenyl, tetrahydroquinolinyl and julolidinyl groups respectively, with the same isophorone-derived tetraene bridges and strong CF3–TCF acceptors. The progressively increased electron-donating strength for these chromophores allows for the fine-tuning of their molecular ground-state polarization, being very close to optimal for very large hyperpolarizability (β), as a function of the local dielectric environment and poling-induced acentric ordering. The solvatochromic study and DFT calculations suggested that more dipolar chromophores 2 and 3 with stronger donating groups can be polarized quite close to the cyanine limit, or even beyond that into the zwitterionic regime in the most polar solvents to give the inverted solvatochromism and diminished β values. This is in stark contrast to the polyene-like characteristic of 1 with the diethylaminophenyl donor in all the tested solvents. Most intriguingly, the electric field poling has induced significant changes in the position, intensity and shape of the chromophoric charge-transfer absorption band in their poled thin films. It is thus indicated that the nontrivial intermolecular interaction in solid state can vary the reaction field that acts on the chromophores in poled and depoled films, and significantly affect their achievable electro-optic (EO) activities. As a result, the guest–host polymers containing 10 wt% of chromophores in PMMA showed EO coefficients of ∼80 pm V−1 for 1/PMMA and 2/PMMA, while dramatically dropping to 20 pm V−1 for 3/PMMA. These systematic analyses led to the rational design of a new guest–host EO polymer incorporating 35 wt% of a spatially modified chromophore AJLZ55, which gave ultrahigh EO coefficients of 218 pm V−1 at 1.31 μm.
A note on the weight and the gravitational torque of a subducting slab

Abstract An analytic model to evaluate the magnitudes of gravitational torques acting on subducting plates has been developed. Contrary to a previous notion that gravitational torques have no angular dependence except through the moment arms, they are found to possess a maximum magnitude when a slab is dipping between 15°–45° depending on subduction velocity and slab length, and they will become small and vanish when slab dips become either horizontal or vertical. This new result does not significantly affect the qualitative arguments for the origin of slab-dip angles proposed by previous investigators, however, because of the dominance of the dynamic pressure torque at small dip angles where most of the differences occur.
Practical success and the nature of truth

Philip Kitcher has argued for a causal correspondence view of truth, as against a deflationary view, on the grounds that the former is better poised than the latter to explain systematically successful patterns of action. Though Kitcher is right to focus on systematically successful action, rather than singular practical successes, he is wrong to conclude that causal correspondence theories are capable of explaining systematic success. Rather, I argue, truth bears no explanatory relation to systematic practical success. Consequently, the causal correspondence view is not in a better position to explain success than the deflationary view; theories of truth are the wrong place to look for explanations of systematic practical success.
Impact of Acute Pulmonary Rejection on Cardiac Function

Background Experiments were designed to define cardiac function in dogs with single lung allografts during acute rejection of the allografted lung. Methods and Results Left lungs were either autotransplanted (n=4) or allotransplanted (n=8) in adult male mongrel dogs. All allotransplanted animals were maintained on triple-drug immunosuppression (cyclosporine, azathioprine, and steroids) for 5 days after the operation. In 4 allotransplanted animals, treatment was discontinued, allowing the animals to reject (usually after a further 3 days; rejecting group); 4 other allotransplanted animals were maintained on immunosuppression for an additional 3 days (immunosuppressed group). Another group of dogs were not operated on but were maintained on the same immunosuppression as the rejecting group (controls). All experimental animals underwent fast computed tomographic scanning with measurement of left ventricular pressure and calculation of ventricular chamber volumes, cross-sectional areas of coronary arteries, m...
Dimerization of the Agrobacterium tumefaciens VirB4 ATPase and the effect of ATP‐binding cassette mutations on the assembly and function of the T‐DNA transporter

The Agrobacterium tumefaciens VirB4 ATPase functions with other VirB proteins to export T-DNA to susceptible plant cells and other DNA substrates to a variety of prokaryotic and eukaryotic cells. Previous studies have demonstrated that VirB4 mutants with defects in the Walker A nucleotide-binding motif are non-functional and exert a dominant negative phenotype when synthesized in wild-type cells. This study characterized the oligomeric structure of VirB4 and examined the effects of Walker A sequence mutations on complex formation and transporter activity. VirB4 directed dimer formation when fused to the amino-terminal portion of cI repressor protein, as shown by immunity of Escherichia coli cells to λ phage infection. VirB4 also dimerized in Agrobacterium tumefaciens, as demonstrated by the recovery of a detergent-resistant complex of native protein and a functional, histidine-tagged derivative by precipitation with anti-His6 antibodies and by Co2+ affinity chromatography. Walker A sequence mutants directed repressor dimerization in E. coli and interacted with His-VirB4 in A. tumefaciens, indicating that ATP binding is not required for self-association. A dimerization domain was localized to a proposed N-terminal membrane-spanning region of VirB4, as shown by the dominance of an allele coding for the N-terminal 312 residues and phage immunity of host cells expressing cI repressor fusions to alleles for the first 237 or 312 residues. A recent study reported that the synthesis of a subset of VirB proteins, including VirB4, in agrobacterial recipients has a pronounced stimulatory effect on the virB-dependent conjugal transfer of plasmid RSF1010 by agrobacterial donors. VirB4′312 suppressed the stimulatory effect of VirB proteins for DNA uptake when synthesized in recipient cells. In striking contrast, Walker A sequence mutants contributed to the stimulatory effect of VirB proteins to the same extent as native VirB4. These findings indicate that the oligomeric structure of VirB4, but not its capacity to bind ATP, is important for the assembly of VirB proteins as a DNA uptake system. The results of these studies support a model in which VirB4 dimers or homomultimers contribute structural information for the assembly of a transenvelope channel competent for bidirectional DNA transfer, whereas an ATP-dependent activity is required for configuring this channel as a dedicated export machine.
Effect of a Performing Arts Program on the Oral Language Skills of Young English Learners.

Although English oral language proficiency in the primary grades is critical to the literacy development of English learners (ELs), we know little about how to foster these skills. This study examined a yearlong K–2 drama and creative movement intervention. A randomized experimental design (N = 5,240) was used to address two research questions: (1) Did participating ELs perform better on oral language assessments than those who did not receive the intervention? (2) Was the impact of the program moderated by students' baseline English-language skills? Student speaking and listening skills were measured using the California English Language Development Test. The treatment group (N = 902) outperformed controls (N = 4,338) on speaking assessments. ELs with the most limited English speaking abilities at baseline benefited most from the program.
The effect of reinforcement stability on composition redistribution in cast aluminum metal matrix composites

Abstract A detailed microstructural characterization was performed on cast Al-7Si particulate-reinforced metal matrix composites (where the composition is in approximate weight per cent) which included extensive examination of particulate-matrix interfacial precipitation reactions. Essentially no reaction products were observed at the interface of SiC particulates. In sharp contrast, however, an extensive reaction product zone was observed at the interface and at near-interface regions of B4C reinforcement. The type of reinforcement was shown to have a profound effect on the interfacial precipitation, the elemental composition distribution and the as-cast and solution-treated-and-aged microstructures of the matrix alloy. The stability of SiC particulates in the A356 matrix alloy (Al-7Si-0.35Mg-0.2Ti) was substantially greater in comparison with highly reactive B4C particulates. Electron microprobe, scanning electron microscopy and scanning transmission electron microscopy were used to identify and analyze phases associated with the bulk matrix microstructure and the particulate-matrix interfacial reaction zones. The extensive matrix-reinforcement reactions caused selective partitioning of matrix alloying elements, thereby modifying the matrix microstructure in the composites by compositional redistribution in the matrix. B4C significantly modified the matrix microstructure of the composite, whereas the matrix containing SiC particulates remained essentially unchanged.
Corporate sponsorship of events and tax implications: is there an opportunity for global co‐ordination?

Corporate sponsorship of sporting and cultural events has emerged as a critical component of global promotion strategy. Global sponsorship by multinationals could be made more cost‐effective with similar and generally consistent taxation legislation worldwide. International environmental and quality management standards such as ISO 14000 and ISO 9000 are examples of global standards that have emerged due to the increasingly international nature of commerce. Describes the tax implications of corporate sponsorship utilizing the USA and Ireland as illustrative examples, provides general guidelines for other nations including the UK, and suggests that sponsorship regulations be made more consistent globally.
Pharmacists' views about health promotion practices.

A mail survey was conducted among a sample of 1,115 Mississippi pharmacists. The survey instrument included 25 statements concerning personal health practices which the respondents were asked to rate, using a Likert scale, on their importance to the health of an average person. Only one item, “Avoidance of alcohol altogether,” received a mean score in the unimportant range. The item rated highest was “Taking prescriptions exactly as prescribed.” Paradoxical attitudes concerning cigarettes and vitamins are discussed.
Neurosensory disturbance with rigid fixation of the bilateral sagittal split osteotomy

Twenty-one patients who underwent bilateral sagittal split osteotomies using rigid fixation were evaluated by neurosensory testing. Neurosensory tests included light touch (LT), brush stroke direction (BSD), two-point discrimination (2-P), and temperature (T). Tests were conducted using the two-alternate forced choice method. The density of neurosensory disturbance was examined as well as the incidence of neurosensory disturbance as it correlated with age of the patient. The incidence of neurosensory disturbance was 45.2% (19/42) to LT, 52.4% (22/42) to BSD, 33.3% (14/42) to 2-P and 7.1% (3/42) to T. The majority of demonstrable neurosensory disturbances were not dense. Increased age was associated with an increased incidence of neurosensory disturbance.
Fine structure and size dependence of exciton and biexciton optical spectra in CdSe nanocrystals

Theory of electronic and optical properties of exciton and biexciton complexes confined in CdSe spherical nanocrystals is presented. The electron and hole states are computed using atomistic $s{p}^{3}{d}^{5}{s}^{\ensuremath{\ast}}$ tight binding Hamiltonian including an effective crystal field splitting, spin-orbit interactions, and model surface passivation. The optically excited states are expanded in electron-hole configurations and the many-body spectrum is computed in the configuration-interaction approach. Results demonstrate that the low-energy electron spectrum is organized in shells $(s,p,\dots{})$, while the valence hole spectrum is composed of four low-lying, doubly degenerate states separated from the rest by a gap. As a result, the biexciton and exciton spectrum is composed of a manifold of closely lying states, resulting in a fine structure of exciton and biexciton spectra. The quasidegenerate nature of the hole spectrum results in a correlated biexciton state, which makes it slowly convergent with basis size. We carry out a systematic study of the exciton and biexciton emission spectra as a function of the nanocrystal diameter and find that the interplay of repulsion between constituent excitons and correlation effects results in a change of the sign of biexciton binding energy from negative to positive at a critical nanocrystal size.
Plasma and surface diagnostics during plasma-enhanced chemical vapor deposition of SiO2 from SiH4/O2/Ar discharges

Abstract Factors affecting the SiOH incorporation into SiO 2 films during plasma-enhanced chemical vapor deposition were studied using in-situ attenuated total reflection Fourier transform infrared spectroscopy, optical emission actinometry, and Langmuir probe measurements. The silane-to-oxygen ratio, R , in the process gas mixture determines the chemical nature of the substrate surface and the incorporation rate of SiOH and SiH into the film. The oxide surface and the film are hydroxyl rich during deposition with SiH 4 -to-O 2 ratio below 0.7. Silicon hydrides are observed on the surface and in the film when R exceeds 0.7. The SiOH concentration in the film correlated well with SiH concentration above the substrate surface, which is representative of the silane fragment (SiH x ) flux arriving at the surface of the growing film. High O flux compared to SiH x flux results in immediate oxidation of the silane fragments adsorbed onto the surface which leads to OH rich surface and SiOH incorporation. As the SiH x flux relative to O flux increases, the reaction of silane fragments with surface. SiOH reduces the SiOH coverage on the surface and the SiOH incorporation rate into the film.
Imaging stress and strain in the fracture of drying colloidal films

Drying-induced fracture limits the applications of thin films based on colloidal materials. To better understand the mechanics of drying, we directly measure the microscopic distribution of strain and stress of a colloidal silica film during the course of drying and cracking. We observe the build-up and release of internal stresses inside the film before and after the opening of individual cracks, and extract a critical stress for fracture of approximately 1 MPa. We also find an inherent time scale for stress relaxation within the film of 25 minutes, likely due to the competition between elastic deformation of and solvent flow through the porous particle network. By correlating the stress and strain, we estimate the plane strain Young's modulus of our colloidal film of the order of 100 MPa.
Microethnographies of electronic discourse communities: Establishing exigency for e-mail in the professional writing classroom

Abstract This article shows the way in which microethnography can be an effective tool for analyzing the possibilities and constraints of electronic discourse by overviewing two e-mail ethnography projects, one focusing on the use of e-mail in a workplace setting and one focusing on the analysis of Internet Usenet groups. Ultimately, such approaches can help students better understand electronic rhetoric—the contexts, purposes, and formats—as well as electronic ideology—the power relationships and cultural values that determine not just what is said in electronic environments, but who says it.
FDM bioprinter to promote mesenchymal stem cell chondrogenesis

Tissue and organ shortages are demanding issues that force more than 120,000 people in the United States to suffer while waiting for an available replacement donation. Tissue-engineered constructs utilizing polymer scaffolds are being investigated as viable substitutions to resolve this need. Fused deposition of a designed model is a novel 3D-printing fabrication method that can produce these scaffolds in a biologically supportive environment. Our project aims are two-fold: to modify an existing bioprinter design, and to produce cartilage by directing chondrogenesis from rat mesenchymal stem cells (rMSCs) on a printed scaffold. The bioprinting process consists of four phases: Phase I utilizes a software interface to thermally extrude a layer-by-layer filament of polycaprolactone, and guide a moveable stage to produce a pre-defined three-dimensional scaffold. During Phase II, the scaffold is aseptically prepared for cell deposition using ultraviolet irradiation. Phase III occurs within a novel environmental heating chamber, where rMSCs are dispensed onto the scaffold which is immersed in a collagen I solution to promote cell adhesion. Phase IV transfers the construct to the cell culturing station outside of the device chamber, where biochemical additives will be applied to promote cell differentiation and chondrocyte growth. The design will be evaluated based on in-vitro results from scaffold surface morphology, cell viability after deposition, and cartilage-specific biomarkers.
Synthesis and characterization of poly‐β‐hydroxybutyrate. I. Synthesis of crystalline DL‐poly‐β‐hydroxybutyrate from DL‐β‐butyrolactone

The polymerization of β-butyrolactone was investigated as a possible monomer for a proposed synthesis of the naturally occurring polyester, D-poly-β-hydroxybutyrate (D-PHB). The racemic DL-monomer was used in this initial study to determine the best conditions and catalyst system for use in a subsequent study of the polymerization of optically active β-butyrolactone. In so doing it was found that certain organometallic catalysts (Et2Zn and Et3Al) plus a cocatalyst of water produced highly crystalline samples of polyester from the racemic monomer. This paper describes the synthesis and characterization of the racemic polymer obtained using these catalyst systems, and compares the results obtained with certain other catalysts that were also investigated for this purpose. Examination of the DL-PHB by infrared, NMR, x-ray, and electron microscopy shows that it is possible to synthesize a crystalline racemic polymer that is virtually identical (excepting optical activity) to the naturally occurring polymer, D-PHB.
On the Conundrum of Form and Material in Adorno's Aesthetic Theory

As little as art is to be identified by any other element, it is simply identical with form. For no select category, not even the aesthetically central concept of the law of form, names the essence of art and suffices to judge its products.
Groove GaInAsP laser on semi-insulating InP

A new GaInAsP/InP injection laser was fabricated on semi-insulating substrates. The structure utilises a single LPE growth process on a grooved substrate to form an index guided device. Current confinement was obtained by the semi-insulating InP surrounding the GaInAsP active layer. Threshold current as low as 28 mA with 250 μm cavity length was obtained. The light/current characteristic was linear up to five times I_(th). A single longitudinal mode at 1.20 μm up to 1.3 I_(th) was observed.
Purchasing Raw Material on a Fluctuating Market

The essential decision problem in buying on a fluctuating market is the timing of the purchases and the decision of how much to purchase when the time arises. This study presents a solution to the problem of determining inventories of raw material when the price of this raw material fluctuates from period to period. The study is presented in two parts Part II develops a formal dynamic-programming model and its analytic solution under the assumptions that the following data are available for decision making: a the existing inventory, b the current market price, c the cost of holding inventory and the cost of shortage, and d probability-density functions for future price and demand of the raw material. Part I presents the results of an actual case study that represents a generalization of the model developed in Part II. In the actual case study, not only was information available concerning the probability-density functions for future price, but price forecasts for the next three periods were also available. Because of the difficulty of solving the original dynamic-programming model developed in Part II when the probability-density functions for future price are dependent from period to period, a surrogate model was developed. This surrogate model combines the analytic solution in its original form with a series of simple decision rules which were easily implemented. Percentage cost savings are also presented in Part I.
Research on energy expenditure in individuals with eating disorders: A review

Objective This study reviews the published research on energy expenditure in individuals with anorexia nervosa (AN), bulimia nervosa (BN), and binge eating disorder (BED). Method Individual studies are reviewed and their results summarized. Results The most consistent finding is a reduction in resting energy expenditure (REE) in patients with AN, which increases with increased energy intake and body weight. Data regarding BN are inconsistent. Three available studies in subjects with BED have not found evidence of changes in energy expenditure corrected for lean body mass compared with obese non-binge eaters. Discussion The ability to measure REE reliably and cost-effectively may aid in the refeeding of patients with AN in whom REE is reduced. Changes in individuals with BN and BED have yet to be consistently identified. © 2002 by Wiley Periodicals, Inc. Int J Eat Disord 32: 127–134, 2002.
Subwavelength scale indium tin ox clad optical disk resonators

We optimize the geometry of nano-scale disk optical cavities incorporating planar indium tin oxide (ITO) electrodes. Optimized cavities of sub-wavelength size in all dimensions exhibit enhanced modal properties such as Q-factors exceeding 10^4.
Pseudomonas fluorescens OmpW: Plasmid localization and requirement for naphthalene uptake

Suppressive subtractive hybridization has been utilized to generate a cDNA library of genes differentially expressed in naphthalene grown cells of Pseudomonas fluorescens. The library was devoid of genes known to be associated with naphthalene catabolism, but was enriched in genes related to cellular uptake and efflux systems. The gene for OmpW, which was present in the cDNA library and has been proposed to encode a porin for the transport of hydrophobic molecules, was isolated, cloned, and sequenced. This gene was shown to be exclusively localized on a large catabolic plasmid possessed by the organism, and its specific mutation resulted in the loss of the organism's ability to grow on naphthalene and several other polycyclic aromatic hydrocarbons. It is proposed that a primary response by P. fluorescens to the presence of naphthalene is the elevation of the cellular mechanism(s) required for its assimilation. The presence of genes related to the uptake and efflux mechanisms present following suppressive subtractive hybridization supports this proposal.
Microstructure and Surface Topography Evolution of Ti and Ni Thin Structures

Abstract This paper presents the results of a study of microstructure and surface topography of electron-beam deposited nano-scale (10–500 nm thick) thin films of Ti and Ni. The films are deposited on substrates with different moduli (Ni, NaCl, and Si). The microstructure of each film is characterized using transmission electron microscopy. The surface topography is also studied using atomic force microscopy. The microscopic observations show that the grain size and film roughness increase with increasing film thickness. The grain coarsening observed in Ni films was greater than that observed in Ti films. Furthermore, the effects of coarsening amplitude on (001) oriented NaCl crystals were much greater than those on stiffer (001) oriented silicon substrates. The implications of the results are then discussed for applications of thin films in biomedical engineering, microelectronics, and micro-electro-mechanical systems (MEMS).
On the half-life of Tl204

Samples of Tl/sup 204/ produced in different irradiations and of varying ages were counted in an end-window methane-flow beta-proportional counter for a period of 1.4 years. The decay curves for these samples are identical, and the average value of the half-life is 3.78 the J-57 engin 0.04 years. Intercomparison of the ratio of K x rays to beta-bremsstrahlung and of L x rays to beta-bremsstrahlung between young (few months) and aged (8 years) reactor- preduced, high specific activity solutions of Tl/sup 204/ exhibited no differences which might arise from the presence of a long-lived isomeric state in thallium. Previous results are summarized. (auth)
The implications of poor sleep quality on arterial health in persons with multiple sclerosis

Abstract Background Multiple sclerosis (MS) is associated with increased risk of cardiovascular disease (CVD) and approximately 25–54% of patients report poor sleep quality. There is evidence from the general population of an association between poor sleep and increased CVD risk, but this is poorly understood in MS. Purpose This study examined the association between self-reported sleep quality and arterial health in persons with MS. Methods MS subjects (n = 31) and control subjects (n = 23) were recruited. Control subjects were age and body size matched. All subjects were administered the Pittsburgh Sleep Quality Index (PSQI) to assess self-reported sleep quality. Subjects with a global score >5 were classified as “poor sleepers”. Blood pressure, arterial stiffness, and the forearm blood flow responses following 5-min ischemic occlusion (endothelial function) were measured. Results Nineteen MS subjects and 5 control subjects were classified as “poor sleepers”. AIx was significantly higher in MS subjects who had poor sleep quality (32.5 ± 8.8 vs 22.0 ± 13.2; P Conclusions Markers of arterial dysfunction were significantly higher in MS subjects with poor sleep quality compared to those with good sleep quality. This study suggests novel evidence for the association of CVD risk and sleep quality in MS.
Insulin Fibrillation and Protein Design: Topological Resistance of Single-Chain Analogs to Thermal Degradation with Application to a Pump Reservoir:

Insulin is susceptible to thermal fibrillation, a misfolding process that leads to nonnative cross-b assembly analogous to pathological amyloid deposition. Pharmaceutical formulations are ordinarily protected from such degradation by sequestration of the susceptible monomer within native protein assemblies. With respect to the safety and efficacy of insulin pumps, however, this strategy imposes an intrinsic trade-off between pharmacokinetic goals (rapid absorption and clearance) and the requisite physical properties of a formulation (prolonged shelf life and stability within the reservoir). Available rapid-acting formulations are suboptimal in both respects; susceptibility to fibrillation is exacerbated even as absorption is delayed relative to the ideal specifications of a closed-loop system. To circumvent this molecular trade-off, we exploited structural models of insulin fibrils and amyloidogenic intermediates to define an alternative protective mechanism. Single-chain insulin (SCI) analogs were shown to be refractory to thermal fibrillation with maintenance of biological activity for more than 3 months under conditions that promote the rapid fibrillation and inactivation of insulin. The essential idea exploits an intrinsic incompatibility between SCI topology and the geometry of cross-b assembly. A peptide tether was thus interposed between the A- and B-chains whose length was (a) sufficiently long to provide the “play” needed for induced fit of the hormone on receptor binding and yet (b) sufficiently short to impose a topological barrier to fibrillation. Our findings suggest that ultrastable monomeric SCI analogs may be formulated without protective self-assembly and so permit simultaneous optimization of pharmacokinetics and reservoir life.
From vital signs to clinical outcomes for patients with sepsis: a machine learning basis for a clinical decision support system

Objective To develop a decision support system to identify patients at high risk for hyperlactatemia based upon routinely measured vital signs and laboratory studies. Materials and methods Electronic health records of 741 adult patients at the University of California Davis Health System who met at least two systemic inflammatory response syndrome criteria were used to associate patients’ vital signs, white blood cell count (WBC), with sepsis occurrence and mortality. Generative and discriminative classification (naive Bayes, support vector machines, Gaussian mixture models, hidden Markov models) were used to integrate heterogeneous patient data and form a predictive tool for the inference of lactate level and mortality risk. Results An accuracy of 0.99 and discriminability of 1.00 area under the receiver operating characteristic curve (AUC) for lactate level prediction was obtained when the vital signs and WBC measurements were analysed in a 24 h time bin. An accuracy of 0.73 and discriminability of 0.73 AUC for mortality prediction in patients with sepsis was achieved with only three features: median of lactate levels, mean arterial pressure, and median absolute deviation of the respiratory rate. Discussion This study introduces a new scheme for the prediction of lactate levels and mortality risk from patient vital signs and WBC. Accurate prediction of both these variables can drive the appropriate response by clinical staff and thus may have important implications for patient health and treatment outcome. Conclusions Effective predictions of lactate levels and mortality risk can be provided with a few clinical variables when the temporal aspect and variability of patient data are considered.