cssi/SciSciGPT-SciSciNet huggingface dataset:
Aerosol-assisted self-assembly of mesostructured spherical nanoparticles

Nanostructured particles exhibiting well-defined pore sizes and pore connectivities (1-, 2-, or 3-dimensional) are of interest for catalysis, chromatography, controlled release, low dielectric constant fillers, and custom-designed pigments and optical hosts. During the last several years considerable progress has been made on controlling the macroscopic forms of mesoporous silicas prepared by surfactant and block copolymer liquid crystalline templating procedures. Typically interfacial phenomena are used to control the macroscopic form (particles, fibers, or films), while self-assembly of amphiphilic surfactants or polymers is used to control the mesostructure. To date, although a variety of spherical or nearly-spherical particles have been prepared, their extent of order is limited as is the range of attainable mesostructures. They report a rapid, aerosol process that results in solid, completely ordered spherical particles with stable hexagonal, cubic, or vesicular mesostructures. The process relies on evaporation-induced interfacial self-assembly (EISA) confined to a spherical aerosol droplet. The process is simple and generalizable to a variety of materials combinations. Additionally, it can be modified to provide the first aerosol route to the formation of ordered mesostructured films.
Adsorbate structure and substrate relaxation for the Sb/Si(001)-(2×1) surface

Abstract X-ray standing wave measurements were undertaken to study the bonding position of Sb adatoms on the Sb-saturated Si(001)-(2 × 1) surface. Using the (004) and (022) Bragg reflections, we find that the Sb atoms form dimers, and that the center of the Sb ad-dimers lies 1.64 A above the bulk-like Si(004) surface atomic plane. When combined with a previous determination of the SbSi and SbSb bond lengths, our results show that the surface Si plane is contracted inward by 0.10 A upon saturation with Sb. Our in-plane results are compared to two structural models consisting of dimers whose bonds are parallel to the surface plane and whose centers are either shifted or unshifted (parallel to the dimer bond direction) relative to the underlying substrate planes. We thus find two special cases consistent with our data: one with symmetric (unshifted) dimers having a dimer bond length of 2.81 A, and the other with midpoint-shifted dimers, having a bond length of 2.88 A and a lateral shift of 0.21 A.
Genome signals and assembly

Quality of genome assembly depends to a large extent on the structure of genomic sequences, notably signals such as repeats, polymorphisms, and nucleotide asymmetry as well as structural motifs (see Statistical signals) such as protein motifs (see Computational motif discovery), gene promoters, enhancers and suppressors (see Promoter prediction and Exon splicing enhancers), transcription factor binding sites, exon/intron splice junctions, regions of homology between sequences (see IMPALA/RPS-BLAST/PSI-BLAST in protein sequence analysis), and protein docking sites. We address probabilistic and statistical issues, departing from modeling the genome assembly as a binomial/Poisson process and considerations of contig size. We then consider estimation of genome size, when repeats are involved, and estimation of the total gap length and of the stringency ratio. Then we consider bubble smoothing in the context of polymorphisms and empirical estimates of the impact of low GC contents on stringency. Finally, we refer to some special issues and examples. Keywords: annotation by words; binomial/Poisson process; EM algorithm; estimating genome length; expected contig size; gap statistics; nucleotide asymmetry; polymorphism; repetitive elements
Biomaterials for mRNA delivery

Messenger RNA (mRNA) has recently emerged with remarkable potential as an effective alternative to DNA-based therapies because of several unique advantages. mRNA does not require nuclear entry for transfection activity and has a negligible chance of integrating into the host genome which excludes the possibility of potentially detrimental genomic alternations. Chemical modification of mRNA has further enhanced its stability and decreased its activation of innate immune responses. Additionally, mRNA has been found to have rapid expression and predictable kinetics. Nevertheless, the ubiquitous application of mRNA remains challenging given its unfavorable attributes, such as large size, negative charge and susceptibility to enzymatic degradation. Further refinement of mRNA delivery modalities is therefore essential for its development as a therapeutic tool. This review provides an exclusive overview of current state-of-the-art biomaterials and nanotechnology platforms for mRNA delivery, and discusses future prospects to bring these exciting technologies into clinical practice.
Internal conversion in poly(1-vinylnaphthalene)—IV. Photochemical processes in polymeric systems☆☆☆

Abstract Quantum yields of all major photoprocesses have been measured on poly(1-vinylnaphthalene) in fluid solution. These measurements indicate that approx. 84% of the excitation energy is deactivated through internal conversion processes ( S 0 ↞ S 1 ). Time resolved emission and absorbance measurements have been used to characterize the excited states in this system. It appears that several different types of singlet and triplet traps may be distinguished, one of which is the monomeric excited singlet. Existence of two different singlet excimers are postulated in order to interpret the time resolved emission data.
Evaluation of Kevlar-29 vs Nylon for 3.81 m (12.5 ft) Diam Ribbon Parachutes

A series of 12 sled-launched tests were conducted to evaluate the suitability of Kevlar-29 as a replacement for nylon in parachute construction. Kevlar-29 was found to be a suitable replacement for nylon in parachute construction with an attendant 50% saving in weight and volume. However, different design techniques than those used for all-nylon parachutes were found to be necessary when horizontal ribbons made of Kevlar-29 were used.
Design for a study to determine optimal dosage of ascorbic acid and alpha-tocopherol in humans

Some clinical trials of vitamins C and E have neglected important design features. Our objective was to demonstrate a detailed design that includes essential elements for an effective study of these vitamins in vivo. While taking 400 IU (international units) of vitamin E, subjects took different dosages of vitamin C during three distinct periods. Dosages were 200 mg in food, 500 mg as supplements twice a day (500 × 2), and 1,000 mg as supplements twice a day (1000 × 2). Ten participants spent 3 weeks at each dosage before plasma was drawn on two consecutive days. Final samples were taken after a week with no supplementation. Selected by investigators at four institutions, endpoints were protein carbonyls, TBARs (thiobarbituric reactive substances), and Heinz body formation in RBCs (red blood cells). TBARs and protein carbonyls did not change significantly with dosage. However, Heinz body formation increased at either higher or lower intakes of vitamin C. Even with daily vitamin E, Heinz bodies were significantly fewer at 500 × 2. Results indicate that even with 400 IU vitamin E daily, it is possible to distinguish the effect of different levels of vitamin C with Heinz bodies. This effect may be due to pro-oxidant action of vitamin C or to prolonged survival of RBCs.
Cytology, colposcopy, and directed biopsy: what are the limitations?

Abstract A quality control study for the evaluation and understanding of the limitations of cytology, colposcopy, and directed biopsy is presented. The importance of strict criteria for satisfactory and unsatisfactory colposcopic examinations is stressed. One may indeed decrease the need for conization in those patients who have a satisfactory colposcopic examination and directed biopsy if the criteria are adhered to. The need to maintain colposcopic skills by quality control studies of a sufficient number of patients with abnormal cytology is emphasized especially since the overall incidence of invasive disease is so low in the general population and the possibility of error with microinvasion can easily occur. The study made clear the need for quality control evaluations at intervals in order to maintain the accuracy of cytology at an acceptable level. Finally, the necessary skill in colposcopy cannot be gained in a few days, nor can it be maintained except in a clinical setting where large numbers of abnormal cytologic smears are produced.
Potential energy surfaces for heavy nuclei in the two-center model

Abstract Potential energy surfaces have been calculated for heavy nuclei in the framework of the two-center model, which has here been extended to realistic nuclear shapes. These surfaces are shown in a two-dimensional representation as a function of two parameters, one of which is a measure of the elongation of the nuclear shape and the other a measure of its constriction. The surfaces are discussed in comparison with other theoretical results and experimental information. Finally the influence of fragment shells on the potential energy surface is investigated. It is found that this influence is important already at early stages of the fission process.
Effects of surface activity, defects and mass transfer on hydrogen permeance and n-value in composite palladium-porous stainless steel membranes

Abstract The H 2 permeance of composite palladium-porous stainless steel (Pd-PSS) membranes was determined: (1) by assuming Sieverts’ law ( n = 0.5) and (2) by performing a non-linear fit in order to obtain the hydrogen permeance and the n -value. For all membranes (thickness > 15 μm) the n -value was higher than 0.6 at low temperatures ( 400 °C). The activation of the membrane with the surface either seeded with palladium or oxidized in air at 350 °C for 48 h led to lower n -values indicating that the surface reaction rate even in thick membranes with selectivities (H 2 /He) above 400 might still contribute, though to a minor extent, to the overall hydrogen permeation mechanism. For leaky membranes (selectivity ≪ 400) the Knudsen diffusion and viscous flow of molecular H 2 through the defects led to n -values as high as 0.75 at 500 °C. n -Values higher than 0.5 were also found for Pd-PSS membranes when the PSS support had a large resistance.
A system's approach to improve organ donation

Using lessons learned from the US Department of Health and Human Services National Donation Breakthrough Collaborative, New York-Presbyterian Healthcare System (NYPHS) partnered with 5 donor service areas covering its member hospitals to improve donation across the system. By integrating established communication networks with the "spread" techniques of the Breakthrough Collaborative, the NYPHS identified hospital champions and best practices and established standardized outcome metrics. The improvements that resulted were a sustained increase of 40.23% in consent rate and an initial 41.7% increase in conversion rate during the first 6 months, although that conversion rate was not sustainable. During the 8 measured periods, 21 hospitals met or exceeded the 75% conversion rate during 1 or more quarters. NYPHS was able to spread these successes and outcome metrics through its established communication networks of quarterly report cards, regular senior leader meetings, and real-time access to a secure member-only Web site, thus keeping organ and tissue donation at the forefront of hospital leaders' priorities.
Spectral mechanisms of spatially induced blackness: data and quantitative model

Spectral efficiency functions and tests of additivity were obtained with three observers to identify possible chromatic contributions to spatially induced blackness. Stimuli consisted of a series of monochromatic (400–700 nm; 10-nm steps), 52-arcmin circular test lights surrounded by broadband (x=0.31, y=0.37), 63–138-arcmin annuli of fixed retinal illuminance. The stimuli were imaged on the fovea in Maxwellian view as 500-ms flashes with 10-s interstimulus intervals. Observers decreased the intensity of the test center until it was first perceived as completely black. Action spectra determined for two surround levels [2.5 and 3.5 log trolands] had three sensitivity peaks (at approximately 440, 540, and 600 nm). However, when monochromatic surrounds were adjusted to induce blackness in a broadband center, action spectra were unimodal and identical to functions obtained by heterochromatic flicker photometry. Tests of additivity revealed that when blackness is induced by a broadband surround into a bichromatic center, there is an additivity failure of the cancellation type. This additivity failure indicates that blackness induction is influenced, in part, by signals from opponent-chromatic pathways. A quantitative model is presented to account for these data. This model assumes that blackness induction is determined by the ratio of responses to the stimulus center and the annulus, and while signals from the annulus are based only on achromatic information, responses from the center are based on both chromatic and achromatic properties of the stimulus.
Electoral Competition and the Growth of Public Spending in 13 Industrial Democracies, 1950 to 1983

This article examines a theoretically important issue that has received surprisingly little attention: whether the process of democratic competition for public office has fueled the growth of domestic spending in the capitalist democracies since World War II. Probably because it is difficult to measure electoral competition in multiparty systems, existing comparative studies of public spending either ignore this question or use dubious measures of electoral competition. This study presents and tests some conceptually more appealing measures of competition. The results show a strong, robust relationship between improved indicators of electoral competition and the growth of domestic spending from 1950 to 1973 and 1973 to 1983. The study concludes by analyzing the implications of the findings for economic performance in the capitalist democracies and for the democratic management of fiscal policy.
Low-Temperature Simulation of Hypersonic Melting Ablation and the Observed Wave Patterns

Low temperature simulation of hypersonic melting ablation and wave patterns of gas-liquid interface
Developing preservice teachers' pedagogical content knowledge of slope

Abstract Three preservice teachers participated in a secondary mathematics methods course and then taught a basic algebra course. The study examined the development of their knowledge of students' difficulties with slope and their knowledge of representations for teaching slope. Data sources included written assignments, interview transcripts, and transcripts of the basic algebra lessons. The preservice teachers focused on conceptual and procedural aspects of students' knowledge and developed a variety of representations for teaching slope. However, they inconsistently developed the concept of slope in real-world situations. The development of pedagogical content knowledge of slope may require the use of nontraditional curriculum materials.
Presence of glutamine and asparagine in enzymatic hydrolysates of oxytocin and vasopressin.

SummaryIn papain hydrolysates of oxytocin and vasopressin, asparagine and glutamine were found to be present. The asparagine and glutamine were identified by chromatography on paper and starch.
Border molding in mandibular denture impressions

A modification of the border molding technique for lower dentures has been presented to increase the accuracy of this procedure.
Discontinuous Polyacrylamide Electrophoresis for β-Lactoglobulin Typing of Cow's Milk

Abstract The use of a spacer gel, in vertical polyacrylamide gel electrophoresis for β -lactoglobulin typing, gives better results than previous methods where only one gel concentration was used. The method is a modification of that in Technical Bulletin 140 of the E-C Appartus Corporation. The advantages of the method are speed, improved resolution, economy (cost of chemicals reduced by 50%), and dependability.
A rapid spectrophotometric method for the determination of esterase activity

We have developed a spectrophotometric assay method which continuously records esterase activity at 510 nm by monitoring absorbance changes due to the formation of a diazo dye complex. In our method, alpha-naphthyl ester substrates are hydrolyzed by enzymatic action to alpha-naphthol which couples to Fast Blue RR salt (a diazonium salt) forming a diazo dye complex. Our method is unique in directly monitoring the formation of the diazo dye complex without extracting the color of the complex as in other methods that use naphthyl esters and diazo coupling of reaction products. The method appears to be limited to alpha-naphthyl ester substrates, however, since beta-naphthyl esters did not give a linear change in absorbance in the enzymatic reactions tested. With this assay method, one can use a single substrate both to determine esterase units quantitatively in solution and to detect esterase staining activity on gel electrophoresis.
Economic feasibility of using composted feedlot manure on dryland maize

Abstract The economic feasibility of using composted manure from KwaZulu-Natal midlands feedlots in combination with commercial N in production of dryland grain maize [Zea mays (L.)] was evaluated. Effective disposal of large quantities of manure from large scale feedlots is a concern. Yield data from Cedara experiment station were used to estimate a quadratic production function where maize grain yield is a function of manure and commercial fertiliser N application rates. Four rates of commercial N (0, 50, 100 and 200 kg ha−1) and five rates of composted feedlot manure (0, 5, 10, 20 and 30t ha−1, as is basis) in a factorial arrangement were applied to dryland maize. The production function estimate was used to determine the combination of composted manure and commercial N, which maximized net returns. The results suggest that a compost application rate of 15t ha−1 with 20 kg ha−1 of commercial N would be economically feasible when the price of commercial N, including application charges, is R4.50 kg−1 an...
Lattice damage in ion implanted silicon-germanium alloys

The damage produced in Si{sub 1-x}Ge{sub x} alloys (0{le}x{le}1) by implantation of 70--100 keV {sup 30}Si{sup +} has been measured as a function of temperature and fluence by ion channeling. For all compositions, the damage efficiency decreased sharply as the implant temperature was increased between room temperature and 150{degrees}C. Furthermore, the damage efficiency in alloys of intermediate compositions (0.34{le}x{le}0.5) exceeds that in Ge, especially at elevated temperatures, despite the larger cascade energy density in Ge. It is shown that this behavior can be described based on a model in which the point-defect mobility is the dominant factor controlling damage retention, rather than the cascade energy density. This approach provides a framework for understanding other temperature-dependent phenomena related to damage growth in Si-Ge alloys including dose-rate effects and damage saturation in MeV implantation.
Measurements with a 35 psec gate time microchannel plate camera

Measurements of the x-ray gate time of 0.2 mm thick microchannel plates with an L/D aspect ratio of 20 as opposed to the more usual L/D=40, demonstrate that gate times of 35 ps can be achieved. Good agreement with time dependent modelling is demonstrated. 7 refs., 4 figs., 2 tabs.
Progress Towards a Vaccine for Lyme Disease

Although Lyme disease was first described no more than 20 years ago, knowledge has accumulated to the point that prototype vaccines are currently in advanced stages of clinical trials. A mouse model of Lyme disease facilitated efforts to describe protective immunity, which appears to depend mainly on the presence of antispirochaetal antibody. A recombinant major outer surface protein A (rOspA) fully protects mice and other hosts against infection and disease. A unique mode of action is apparent in that circulating antibody is ingested during the bloodmeal taken by the infectious tick, and serves to attenuate or destroy spirochaetes before they are transmitted to the vaccinated host. To date, 2 prototype Lyme disease vaccines, based upon rOspA, appear to be immunogenic and safe in humans. Testing such vaccines for efficacy will require careful surveillance of thousands of subjects and may take many years for completion, given the chronic nature of Lyme disease and the requirement that a vaccine induce a response that prevents infection as well as disease.
Adenovirus Serotype 5 Neutralizing Antibodies Target both Hexon and Fiber following Vaccination and Natural Infection

The immunogenicity of adenovirus serotype 5 (Ad5) vectors has been shown to be suppressed by neutralizing antibodies (NAbs) directed primarily against the hexon hypervariable regions (HVRs). However, the role of NAbs directed against other capsid components, particularly the adenovirus fiber, remains unclear. Here we show that Ad5 NAbs target both hexon and fiber following vaccination and natural infection. Utilizing neutralization assays with capsid chimeric vectors, we observed that NAb responses to hexon appeared dominant and NAb responses against fiber were subdominant in sera from vaccinated mice, vaccinated humans, and naturally exposed humans. A novel chimeric Ad5 vector in which both the hexon HVRs and the fiber knob were exchanged nearly completely evaded Ad5-specific NAbs both in vitro and in vivo.
A solution to a problem of Dubins and savage

A problem left open in Dubins and Savages' "How to Gamble if You Must" is solved. Introduction In section 3, chapter 8 of Dubins and Savage [1] the question is raised as to whether or not stationary gambling houses on (-c~, oo), with utility function /{x>0}, can admit value functions which are both continuous mid not strictly increasing. The purpose of this paper is to provide a reasonably simple example having both properties. Main Section The idea is to modify the following simple stationary gambling house which has only one gamble available at each fortune x: 2 1~ l"(x) = {"/=} where ~', : 5~,_1 + 5 "+" This gambling house has a utility function given by U(x)=I if x>_0; = 2 if x < 0 . The utility function for the house should be thought of as the probability (under the optimal strategy) of attaining the positive half line, [0, oo). We will supplement this gambling house by an infinite set of gambles {Ai)iel with the property * Research partially supported by NSF Grant DMS 91-57461. Received October 28, 1991 and in revised form August 19, 1992
Demonstration of the auxiliary-field Monte Carlo approach for sd-shell nuclei

We apply the auxiliary-field Monte Carlo approach to the nuclear shell model in the 1s-0d configuration space. The Hamiltonian was chosen to have isovector pairing and isoscalar multipole-multipole interactions, and the calculations were performed within the fixed-particle, canonical ensemble. The results demonstrate the feasibility of the method for N≠Z even-even and odd-odd N=Z nuclei. In particular, static observables for even-even Ne isotopes and 22Na compare well with results obtained from exact diagonalization of the Hamiltonian. Response functions are presented for 22Ne and compared with exact results, and the viability of cranked calculations for N≠Z even-even nuclei is addressed. We present methods for computing observables in the canonical ensemble using Fourier extraction, and for determining the nucelar shape.
HOW CAN SCIENCE HELP US CARE FOR NATURE? HERMENEUTICS, FRAGILITY, AND RESPONSIBILITY FOR THE EARTH

In this review essay, Clarence Joldersma argues for a novel role for science in developing an affirmative answer to his title question, “How can science help us care for nature?” He does so in dialogue with Clare Palmer's edited volume, Teaching Environmental Ethics, Dirk Postma's Why Care for Nature? and Michael Bonnett's Retrieving Nature. Joldersma suggests that although each book can help address the issue of how to teach students to care for nature, he parts company with their stance that we must go beyond science to develop a metaphysics of nature adequate to the task. Relying on the same Heideggerian framework as Postma and Bonnett, Joldersma comes to a different assessment of the role of science. He does so by arguing for a hermeneutic understanding of science as social practice and by claiming that science so construed can disclose the planet as earth (in the later Heidegger's sense), for which we owe thanks. This disclosure reveals earth as that which is fragile and for which we are responsible.
Phase II trial of erlotinib in women with squamous cell carcinoma of the vulva

Abstract Objective To evaluate the efficacy and toxicity of erlotinib in the management of squamous cell carcinoma (SCC) of the vulva. Methods Patients with vulvar lesions amenable to surgery or chemoradiation (cohort 1) or those with metastatic measurable disease (cohort 2) received erlotinib 150mg daily. Patients were monitored for toxicity. Responses were determined by digital photography or RECIST 1.1. Cohort 1 underwent pre and post treatment biopsies. EGFR immunohistochemistry (IHC), fluorescence in-situ hybridization (FISH), and mutational analysis were performed. Results 41 patients were enrolled: 17 in cohort 1 and 24 in cohort 2. Notable grade 3 or 4 toxicities included allergic reaction (1), diarrhea/electrolyte abnormalities (3), ischemic colitis (1), and renal failure (3) and electrolyte abnormalities (n=2). Mean number of cycles for cohort 2 was 3.3. Overall clinical benefit rate was 67.5% with 11 (27.5%) partial responses (PR), 16 (40.0%) stable disease (SD), and 7 (17.5%) progressive disease. Responses were of short duration. All pre and post treatment biopsies exhibited 2–3+ EGFR staining. 5 of 14 patients (35%) were found to have EGFR amplification (n=3) or high polysomy/trisomy (n=2). These five patients had either a PR (n=3) or SD (n=2). Gain of function mutations were not been identified. Conclusions This is the first reported controlled trial evaluating erlotinib for the management of vulvar carcinoma. Toxicities were acceptable given the lack of treatment options for these patients. Given the observed clinical benefits erlotinib may represent one of the most active agents available to treat vulvar SCC.
Metal−Organic Frameworks from Silicon- and Germanium-Centered Tetrahedral Ligands

Metal−organic frameworks (MOFs) have been constructed from the reaction of Si(C6H4CO2H)4 and of Ge(C6H4CO2H)4 with Zn(II). The two structures are quite different from each other, and both are different from that of the known MOF of C(C6H4CO2H)4 with Zn(II). The zinc portion of the carbon system is a dinuclear zinc-oxo cluster with square-planar geometry, that of the silicon system consists of zinc-oxo chains containing two zinc atoms with different geometries, and that of the germanium system consists of linear zinc-oxo clusters containing three zinc atoms with two different geometries. For the silicon system, the secondary building unit around zinc is a distorted tetrahedron, whereas for the germanium system, the secondary building unit around zinc is a bipyramid with eight coordination. The differences in morphology may be due to the more open geometry provided as the M−C bond increases from carbon to germanium. Both MOFs have considerable vacancy in the crystal lattice, calculated to be ca. 42% for the...
Carbide phases on iron-based Fischer-Tropsch synthesis catalysts part I: Characterization studies

The characterization of iron carbide phases formed on iron-based Fischer-Tropsch catalysts is reviewed in this part with particular emphasis on Mossbauer and XPS studies of selected iron and supported iron catalysts, in combination with some specific results in activity and selectivity. Mossbauer studies have shown clearly the evolution of bulk carbide species on iron catalysts under synthesis reaction conditions; the relationship of these to the nature of near-surface species and their temporal evolution under synthesis conditions is indicated by XPS results. Comparisons among reduced, unreduced and carbided iron catalysts are given; XPS and reaction results suggest that Fe3O4 is active for synthesis even in the absence of carbide phases.
Racial Disparity in Surgical Mortality after Major Hepatectomy

Background The relationship between surgical mortality and race has not been studied for major hepatectomy. We sought to quantify and explore the nature of racial disparities in surgical mortality after major hepatectomy in a nationally representative cohort of patients. Study Design We conducted a retrospective cohort study using data from the Nationwide Inpatient Sample (1998 to 2005). Adult patients undergoing major hepatectomy within 1 day of nontrauma admission were included. Logistic regression models were used to assess the variation of in-hospital mortality by race after adjustment for other risk factors. Results The study cohort consisted of 3,552 observations representing 17,794 patients undergoing major hepatectomy. Unadjusted analyses revealed that African-American patients had a two-fold increased odds of surgical mortality (odds ratio 2.22, 95% CI 1.38 to 3.57) relative to Caucasians. Even after adjustment for other risk factors, African Americans had a two-fold increased odds of surgical mortality (odds ratio 2.15, 95% CI 1.28 to 3.61) relative to Caucasians. Stratified analyses restricting the cohort to patients without comorbidities, those with neoplasms, those with private insurance, or those treated at high-volume hospitals all demonstrated racial disparities in surgical mortality. Conclusions In-hospital mortality after major hepatectomy varies substantially by race. After adjustment for potential confounders, African-American patients have two-fold higher population-level odds of surgical mortality than Caucasian patients do. Our analyses suggest that clinical factors, insurance status, and hospital factors do not account for these differences. Additional studies to clarify the nature of this disparity and identify targets for intervention are warranted.
On-chip generation of microbubbles as a practical technology for manufacturing contrast agents for ultrasonic imaging.

This paper presents a new manufacturing method to generate monodisperse microbubble contrast agents with polydispersity index (σ) values of <2% through microfluidic flow-focusing. Micron-sized lipid shell-based perfluorocarbon (PFC) gas microbubbles for use as ultrasound contrast agents were produced using this method. The poly(dimethylsiloxane) (PDMS)-based devices feature expanding nozzle geometry with a 7 μm orifice width, and are robust enough for consistent production of microbubbles with runtimes lasting several hours. With high-speed imaging, we characterized relationships between channel geometry, liquid flow rate Q, and gas pressure P in controlling bubble sizes. By a simple optimization of the channel geometry and Q and P, bubbles with a mean diameter of <5 μm can be obtained, ideal for various ultrasonic imaging applications. This method demonstrates the potential of microfluidics as an efficient means for custom-designing ultrasound contrast agents with precise size distributions, different gas compositions and new shell materials for stabilization, and for future targeted imaging and therapeutic applications.
SOMATIC EMBRYOGENESIS AND PLANT REGENERATION IN TISSUE CULTURES OF PANICUM MAXIMUM JACQ.

Callus tissue cultures were initiated from immature embryos, mature embryos and young inflorescences of Guinea grass (Panicum maximum Jacq.) on Murashige and Skoog's (MS) medium supplemented with 2.5-10 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D). Calluses were transferred onto the same nutrient medium with 0.2 mg/l 2,4-D, or without 2,4-D. In callus cultures derived from immature embryos and young inflorescence segments, plantlets were produced via somatic embryogenesis after 3-5 wk. Young plants were successfully transplanted to pots and grown in the greenhouse. Plant development in callus obtained from mature embryos took place through the organization of shoot meristems. Regenerated plants were shown to have the normal tetraploid chromosome number of 2n = 4x= 32.
Ia-like alloantigens in the chicken: Serologic characterization an ontogeny of cellular expression.

Alloantisera raised in highly inbred lines of chickens, 72 and 15I5 , by reciprocal immunization with lymphocytes were shown by immunofluorescence to react with B cells, cells of the monocyte-macrophage series, and an unidentified population of mononuclear cells prevalent in the spleen and bone marrow. Variable immunogenicity of the ‘Ia’2 and ‘Ia’15 alloantigens was observed. The alloantigens detected by these sara could be redistributed on the B-cell surface independently of immunoglobulin determinants or previously recognized antigens encoded by the major histocompatibility complex (B locus), and were more resistant to proteolysis than slgM. Analysis of several inbred lines of chickens revealed an association between expression of these antigens and the B haplotype. Strains of the B2 haplotype expressed the antigen detected by anti-7 2 and vice versa. These data suggest that the B-cell alloantigens detected are encoded by genes linked to the MHC and may be analogous to la antigens of mice and DR antigens of man. ‘Ia’ alleles were co dominantly expressed on lymphocytes of F1 hybrids. During ontogeny ‘a’+ cells were first detected in the bursa at 10 days of incubation , 3 days before ‘Ia’+. IgM+ cells could be detected. Both ‘Ia’+.IgM+ and ‘Ia’+.IgM− populations of bursal cells increased in parallel until day 18, when plateau levels were reached. Development of ‘Ia’+.IgM− cells throughout the body was unaffected by bursectomy at hatching. Cell surface expression of ‘Ia’ antigens was apparently increased with B-Iymphocyte maturation and was detectable on most, but not all, mature plasma cells.
Supercritical Carbon Dioxide Extraction of Lipids and Cholesterol from Dehydrated Chicken Meat

Supercritical carbon dioxide (SC-CO2) extraction was studied for removal of lipids and cholesterol from dried chicken meat powder and chunks. Two combinations of pressure and temperature were used: 299 atm and 45 C, and 381 atm and 55 C, both providing a fluid density of .90 g/cm3. For a given quantity of CO2, at the higher temperature and pressure, significantly (P < .05) more lipids and cholesterol were extracted from the powder. At 381 atm and 55 C, approximately 89% of the lipids and 90% of the cholesterol were removed from the dehydrated chicken meat powder. With respect to the chunk chicken meat, about 93% of the lipids and 82% of the cholesterol were extracted at 299 atm and 45 C. It seemed that the SC-CO2 extraction process was more efficient when chunks were used. Protein was concentrated as cholesterol and lipids were removed by SC-CO2 extraction of both chicken meat types, and Hunterlab L values increased but aL values decreased, indicating a lighter color with less redness. This research indicated that SC-CO2 extraction holds promise for substantially reducing lipids and cholesterol in chicken meat.
Patterns of grain‐size dependent sediment transport in low‐ordered, ephemeral channels

Sediment data were analyzed to determine grain-size dependant factors affecting sediment transport in a low-ordered, ephemeral watershed. Sediment and flow samples were collected during 22 flow events at the outlet of a 4·53 ha sub-watershed within the Walnut Gulch Experimental Watershed in south-eastern Arizona. Measured concentrations ranged from 4191 to 115 045 mg l−1 and included grain sizes up to 8·0 mm in diameter. Two grain-size dependent transport patterns were observed, that of the finer grain-size fraction (approximately < 0·25 mm) and that of a coarser grain-size fraction (approximately ≥ 0·25 mm). The concentration of the fine fraction decreased with flow duration, peaking near the beginning of a flow event and declining thereafter. The concentration of the fine fraction showed slight trends with season and recovery period. The concentration of the coarse fraction displayed a slight negative trend with instantaneous discharge and was not correlated with event duration. These patterns typically produced a condition where the majority of the fine fraction of the sediment yield was evacuated out of the watershed before the hydrograph peak while the majority of the coarser sediment was evacuated during the falling limb of the hydrograph. Each grain-size dependent transport pattern was likely influenced by the source of the associated sediment. At the flow event time scale, the fines were primarily wash load, supplied from the hillslopes and the coarser grains were entrained from the channel bed. Because transport patterns differ based on grain size, attempts to define the total sediment concentration and sediment yield by the behavior of a single grain-size fraction may lead to erroneous results, especially when a large range of sediment grain sizes are present. Copyright © 2010 John Wiley & Sons, Ltd.
Multispacecraft observations of the hard X-ray emission from the giant solar flare on 2003 November 4

The hard X-ray emission from the giant solar flare on 4 November 2003 (∼1947 UT) was observed by the hard X-ray/gamma ray spectrometer on the Ulysses spacecraft located at ∼114 degrees west of the Sun-Earth line at a distance of 5.28 All from the Sun A small hard X-ray burst during the early rise of the giant flare and a part of the decay of the hard X-ray emission associated with the giant flare were also observed by the hard X-ray imager an the RHESSI satellite located near the Earth. The maximum of the hard X-ray emission during the giant flare could not be observed by the RHESSI instrument because of satellite night. The flare view angles for Ulysses and RHESSI were ∼31° West and 83° East respectively. The H-α flare (importance 3B) was located at S19 W83 in the active region NOAA 10486. GOES observations of the associated soft X-ray emission saturated during the period 1943-1958 UT. It has been estimated that the soft X-ray maximum occurred at ∼1947 UT with peak flux equivalent to NOAA class ≥ X28. OVSA radio observations show that the flare produced intense microwave emission, the peak flux at 15.4 GHz being ∼60 000 sfu at - 1945 UT. Intense type II, III and IV radio hursts have also been reported at metric and decimetric wavelengths. RHESSI has provided 10-100 keV X-ray images and spectra for 1930-1936 UT (the early rise of the flare) and 10-30 keV images and spectra for 2016-2114 UT (a part of the late decay of the flare). Ulysses observed an increase in 25-150 keV X-rays from 1933 UT to 2015 UT with the maximum at ∼1944 UT, almost simultaneously with the maximum in 15.4 GHz radio emission and ∼3 min before the maximum in the soft X-ray emission. This indicates that the X-ray emission observed by Ulysses was mostly non-thermal. An assumed hard X-ray spectrum of ∼E 3.5 photons cm -2 s -1 keV -1 for >20 keV photons leads to an energy dissipation rate of ∼6.4 x 10 31 erg s -1 at the time of the hard X-ray maximum. The total energy in >20 keV electrons released during the flare is estimated to be ∼1.3 x 10 34 erg.
Modification of dopaminergic receptor sensitivity in rat brain after amygdaloid kindling

Alterations in dopaminergic receptor sensitivity in various brain areas have been demonstrated in the rat after the kindling of seizures by repeated amygdala stimulation. Using a radioligand binding assay with [3H]spiroperidol as the ligand and butaclamol as the specific antagonist in crude brain homogenates, high- and low-affinity receptor sites have been shown to be differentially affected in various brain areas with respect to both density of sites and affinity for ligand.
Modern Spin Relaxation Techniques for Liquid Crystals: Nuclear Spin Probes in Thermotropic Mesophases

The existence of well-resolved dipolar and/or quadrupolar splittings in the NMR spectra of solutes in ordered phases greatly facilitates analysis of nulcear spin relaxation pathways in terms of individual spectral density parameters evaluated at well-defined frequencies. Both auto- and cross-correlation terms are experimentally accessible via an appropriate combination of modern pulse techniques, and this detailed information is of use in assessing the validity of various models for molecular motion in ordered systems. Spectral density data for small, rigid solutes in nematic mesophases can be rationalized in terms of rotational diffusion, including effects of static order, together with order director fluctuations. The techniques developed for the simpler nematics can readily be used for solutes in the smectic phase as well as for studies of the liquid crystalline solvent molecules themselves.
Assembly and molecular organization of self-assembled lipid bilayers on solid substrates monitored by surface plasmon resonance spectroscopy.

Abstract The structural properties of lipid films, made from a squalene/butanol solution containing varying amounts (0–15 mg/ml) of egg phosphatidylcholine and deposited on a thin metallic silver layer, were investigated using surface plasmon resonance (SPR) spectroscopy. Optical parameters (thickness, refractive index and extinction coefficient) of such supported self-assembled lipid membranes were obtained from a theoretical analysis of the experimental SPR curves. The mass of the lipid membrane and the area and volume occupied by one lipid molecule were also calculated. The results were consistent with the formation of durable and homogeneous lipid bilayers on the solid substrate, and indicated similarities in structural properties between the present lipid bilayers and freely suspended and Langmuir-Blodgett bilayer membranes. Such bilayers represent a simple model for biological membranes, as well as providing a means of immobilizing proteins for various practical applications, including receptor-based sensors and molecular devices. The results confirm the value of the SPR technique for investigating the properties of thin biomolecular dielectric films deposited on a metal surface.
Basal junctions at synaptic endings of turtle visual cells.

It has been often assumed that the first synapse of the visual pathway is confined to the region where the visual cell ending is indented by processes of other retinal elements (4, 9, 15), identified as horizontal and bipolar cells (11, 16). In the vicinity of the indented area, the visual cells contain small vesicles similar to those found at other synapses (3, 13, 14), and dense lamellae are conspicuously placed between the branches of the indenting processes (9). This recessed junction has received considerable attention in the past, but recently the existence of other junctional areas between visual cells and second order neurons has been suggested in the primate and frog retinas (6, 7, 11). In those instances junctions were found at the basal surface of cone pedicles, and structures interpreted as filaments extending between both cell membranes were noted in the frog retina (6). During the course of previous work on toad and rat retinas, I have also occasionally noticed the presence of opaque cross-bars in the intercellular gaps surrounding visual cell endings. These structures did not seem to be located within the area of the recessed junction, but the complex architecture of the toad and rat retinas made this interpretation
Plasma concentrations of choline in man following choline chloride

Abstract Plasma choline levels were measured in patients being treated with choline chloride for movement disorders. Following single doses of 5 g given orally in aqueous solution, plasma concentrations rose to a peak within four hours and then rapidly declined. The degree of increase was variable both between and within patients. During chronic treatment, plasma choline concentrations tended to rise as the dose increased, although the relationship was not strong. The highest concentrations attained by patients were always at a dose of 16 or 20 g daily. Following chronic treatment, the disappearance of choline from plasma was rapid, with most patients reaching baseline by four days. Choline chloride is generally given in four divided doses, which seems reasonable in the early stages of treatment. Most therapeutic effect is seen when patients are treated with daily doses in the 12 to 20 g range, doses likely to produce substantial increases in plasma choline concentration. However, the relationship of plasma choline concentration to clinical efficacy may be tenuous. Following discontinuation of treatment, clinical improvement tends to persist long after plasma choline has returned to baseline concentrations.
Prevention of Systemic Arterial Embolism in Chronic Rheumatic Heart Disease by Means of Protracted Anticoagulant Therapy

Seven clinic outpatients with mitral stenosis and auricular fibrillation complicated by systemic embolism have been maintained on Dicumarol for periods of 20 to 48 months. None has had a recognized embolism while on therapy. Dicumarol administration has been interrupted in each case for periods of six days to four months. Three additional systemic embolic episodes in two individuals occurred during this interval. Hemorrhagic manifestations have occurred on three occasions. The study suggests that: (a) protracted Dicumarol therapy is an effective means of preventing recurrent embolism in individuals with chronic rheumatic heart disease; (b) it is applicable to the average clinic outpatient.
"About last night": The social ecology of sexual behavior relative to alcohol use among adolescents and young adults in substance abuse treatment.

Abstract Data were collected in face-to-face interviews from 120 substance-abusing adolescents and young adults (87 men, 33 women; M age=17.2 years old) recruited from residential and nonresidential treatment facilities in South Florida. Participants described two recent sexual events, one with and one without concurrent alcohol use. Participants described social aspects of these sexual events, actual and intended behaviors, and their feelings about sex in the two alcohol-use contexts. High levels of discrete, risky behaviors occurred in both contexts. Event analysis produced only limited evidence suggesting a higher level of risk in the alcohol-use context. Participants reported less positive feelings about sex when alcohol was used.
Developing outpatient mental health services for managed care.

This article offers a strategic framework for developing an outpatient mental health service in a managed care environment. The principles discussed have been derived from the development in a university hospital outpatient clinic that serves a mixture of privately and publicly funded patients. The private sector is a more open system in contrast to the public sector in that conservation of resources and stewardship of patients is more of a shared value between payer and provider in the latter. 2 This article first describes the diverse groups that are interested in the success of such an outpatient service. It then offers a set of clinical principles to guide its development and reviews how these services may be implemented.