cssi/SciSciGPT-SciSciNet huggingface dataset:
Design of epitaxial CVD reactors: II. Design considerations and alternatives

Abstract Design of CVD reactors is considered with the objective of maintaining stable boundary layer and achieving uniform deposition based on the theoretical relationships obtained in Part I for the mass transfer coefficient. In addition, a condition for the stability of boundary layer is utilized. A condition for uniform deposition for typical CVD reactors is derived. These considerations lead to two new design alternatives. The first alternative, which ensures uniform deposition over the entire susceptor length, involves making the contour of the reactor top wall follow a certain prescribed shape with a horizontally placed susceptor. The second design alternative. which could conceivably ensure uniform deposition for any length of the susceptor and stable boundary layer for any velocity, involves applying slight uniform suction through the holes/slits between substrates (susceptor portions supporting the substrates). The only limitation on the susceptor length (or the number of substrates) is the depletion of reactants, which can be appropriately accounted for. Detailed design and operating considerations for the design alternative are given.
A LINGUISTIC FRAMEWORK FOR DYNAMIC COMPOSITION OF DEPENDABILITY PROTOCOLS

We present a language framework for describing dependable systems which emphasizes modularity and composition. Dependability and functionality aspects of an application may be described separately providing a separation of design concerns. Futhermore, the dependability protocols of an application may be constructed bottom-up as simple protocols that are composed into more complex protocols. Composition makes it easier to reason about dependability and supports the construction of general reusable dependability schemes. A significant aspect of our language framework is that dependability protocols may be loaded into a running application and installed dynamically. Dynamic installation makes it possible to impose additional dependability protocols on a server as clients with new dependability demands are integrated into a system. Similarly, if a given dependability protocol is only necessary during some critical phase of execution, it may be installed during that period only.
Lowering of Serum Cholesterol and Triglyceride Levels by Balancing Amino Acid Intake in the White Rat

Earlier studies in rats have shown that serum cholesterol levels were significantly lower in rats fed an L-lysine-supplemented ration. This investigation was initiated to determine if the reverse was true. We reasoned that the addition of an incomplete protein to a complete rat ration would bring about an increase in serum lipid levels. This would result from the intermediary metabolic conversion of systemic amin acids not used in protein synthesis. We further postulated that supplementation of the imbalanced protein would obviate the hyperlipidemia. Gelatin was chosen as the incomplete protein since it is deficient in tryptophan, an essential amino acid. Adult male Sprague-Dawley rats fed rations with added gelatin (5, 15 and 25%) for 30 days showed significant increases in serum cholesterol and triglyceride levels. Lipid levels in rats fed L-tryptophan-supplemented diets containing the same levels of gelatin did not differ from those animals fed the control ration. The data indicate that hyperlipidemia results from the feeding of imbalanced protein. Such hyperlipidemia can be obviated by supplementation with the limiting amino acid.
Automated assessment of color Doppler M-mode early diastolic flow propagation features

Color Doppler M-mode echocardiographic imaging has been shown to provide useful information in the evaluation of left ventricular diastolic filling and function. However, descriptors of the spatiotemporal velocity inflow pattern do not take advantage of the full digital velocity map and are not available in an automated fashion. The purpose of this study was to automate the quantification of flow propagation features and evaluate their ability to assess diastolic filling abnormalities. Isovelocity contouring and gradient analysis were applied to identify features of the early filling wave. These feature parameters were compared in normal and diastolic dysfunction patient groups (N=20). Several features allowed classification of the two patient groups with sensitivity and specificity greater than 80%. This automated process may allow these features to be obtained on a regular basis and provide information for diagnosis and assessment of diastolic dysfunction.
Protein Production for Structural Genomics Using E. coli Expression

The goal of structural biology is to reveal details of the molecular structure of proteins in order to understand their function and mechanism. X-ray crystallography and NMR are the two best methods for atomic level structure determination. However, these methods require milligram quantities of proteins. In this chapter a reproducible methodology for large-scale protein production applicable to a diverse set of proteins is described. The approach is based on protein expression in E. coli as a fusion with a cleavable affinity tag that was tested on over 20,000 proteins. Specifically, a protocol for fermentation of large quantities of native proteins in disposable culture vessels is presented. A modified protocol that allows for the production of selenium-labeled proteins in defined media is also offered. Finally, a method for the purification of His6-tagged proteins on immobilized metal affinity chromatography columns that generates high-purity material is described in detail.
Estimation of the fructose diphosphatase-phosphofructokinase substrate cycle in the flight muscle of Bombus affinis.

1. Substrate cycling of fructose 6-phosphate through reactions catalysed by phosphofructokinase and fructose diphosphatase was estimated in bumble-bee (Bombus affinis) flight muscle in vivo. 2. Estimations of substrate cycling of fructose 6-phosphate and of glycolysis were made from the equilibrium value of the (3)H/(14)C ratio in glucose 6-phosphate as well as the rate of (3)H release to water after the metabolism of [5-(3)H,U-(14)C]glucose. 3. In flight, the metabolism of glucose proceeded exclusively through glycolysis (20.4mumol/min per g fresh wt.) and there was no evidence for substrate cycling. 4. In the resting bumble-bee exposed to low temperatures (5 degrees C), the pattern of glucose metabolism in the flight muscle was altered so that substrate cycling was high (10.4mumol/min per g fresh wt.) and glycolysis was decreased (5.8mumol/min per g fresh wt.). 5. The rate of substrate cycling in the resting bumble-bee flight muscle was inversely related to the ambient temperature, since at 27 degrees , 21 degrees and 5 degrees C the rates of substrate cycling were 0, 0.48 and 10.4mumol/min per g fresh wt. respectively. 6. Calcium ions inhibited fructose diphosphatase of the bumble-bee flight muscle at concentrations that were without effect on phosphofructokinase. The inhibition was reversed by the presence of a Ca(2+)-chelating compound. It is proposed that the rate of fructose 6-phosphate substrate cycling could be regulated by changes in the sarcoplasmic Ca(2+) concentration associated with the contractile process.
Accurate and efficient inductance extraction for SoC noise and signal integrity

With the advent of 500 MHz+ SoC designs, recent intensive on-chip inductance research and publications from academia and semiconductor industry have resulted in early adoptions of interconnect inductance extraction tools by state-of-the-art SoC designers for noise and signal integrity modeling. For those early tool developers and adopters, we propose a set of comprehensive criteria toward an on-chip inductance gold standard to insure accuracy. The three essential criteria for an inductance gold standard we propose are: (1) accurate partial inductance formulae; (2) rigorous 3-D electromagnetic field simulations; (3) comprehensive eddy-current-limited loop and mutual inductance extraction. After brief descriptions of three widely used empirical inductance modeling equations, the necessity of a PEEC-based 3-D electromagnetic field simulation is explained by using nanometer-technology-based SoC interconnect cases. For accurate noise and signal integrity predictions, synthesizing RLCK netlists for SPICE-level circuit simulators is then performed to depict the effects caused by the eddy-current-limited loop and mutual inductance extracted using the gold standard.
Detecting fractions of electrons in the high- T c cuprates

We propose several tests of the idea that the electron is fractionalized in the underdoped and undoped cuprates. These include the ac Josephson effect and tunneling into small superconducting grains in the Coulomb blockade regime. In both cases, we argue that the results are qualitatively modified from the conventional ones if the insulating tunnel barrier is fractionalized. These experiments directly detect the possible existence of the chargon---a charge e spinless boson---in the insulator. The effects described in this paper provide a means to probing whether the undoped cuprate (despite its magnetism) is fractionalized. Thus, the experiments discussed here are complementary to the flux-trapping experiment we proposed in our earlier work [T. Senthil and Matthew P. A. Fisher, Phys. Rev. Lett. 86, 292 (2001)].
Electrochemistry combined on-line with atomic mass spectrometry and related techniques for trace-metal analysis and electrode-reaction studies

Abstract Electrochemistry (EC) combined on-line with atomic mass spectrometry (MS) and related techniques (e.g., inductively coupled plasma atomic emission spectrometry, ICP–AES) affords an avenue for analysis of metals present at ultratrace levels and the effective elimination of matrix effects detrimental to atomic MS and spectrometric techniques. In addition, electrode reactions involving inorganic species can be conveniently studied, and analyte accumulated and released from adsorbates or electroactive thin films can be accurately quantified. This review summarizes recent advances based on EC coupled with atomic MS and related techniques for trace-metal analysis and studies of electrode processes. Particular emphasis is placed on EC combined with ICP–MS (EC–ICP–MS) and electrospray–MS (EC–ES–MS). I describe criteria for selecting the suitable EC flow-cell designs and the MS sample-introduction systems or interfaces. The versatility of this hyphenated technique is well reflected in the different systems studied and the possibility of electrolytic and non-electrolytic accumulation of trace analytes for subsequent sensitive MS detections.
Physical properties, geochemistry, and diagenesis of xenarthran teeth: Prospects for interpreting the paleoecology of extinct species

Abstract Xenarthrans (also called edentates) include modern armadillos, sloths, and numerous extinct clades (e.g., glyptodonts and ground sloths) that lack enamel on their teeth. In contrast to mammals with tooth enamel, which oftentimes preserves geochemical proxy data, paleoecological interpretations of xenarthrans based on geochemical analyses (e.g. stable isotopes) have been limited. Xenarthrans have evolved a distinctive outer dentine layer that seems to be the functional analog of enamel. Here we evaluate the physical and chemical properties of xenarthran outer dentine to understand its potential use for investigating geochemical proxies. The mean hardness (H) of xenarthran outer dentine (3.8) is significantly less than that of enamel (5.7) and there is no difference in H between the two main groups, i.e., armadillos (cingulates) and pilosans (sloths). Although the mean H does not change significantly during diagenesis, its range increases, indicating the replacement of secondary minerals (e.g., carbonate representing the lower range) within the original hydroxylapatite mineral lattice. Results of FT-IR analyses indicate that xenarthran outer dentine has a high degree of organics and H2O, similar to normal dentine, and its crystallinity index and carbonate content are affected in varying degrees during diagenesis. Thus, although xenarthran outer dentine functions like enamel, it retains compositional similarities to dentine. The uptake of rare earth elements (REE) was analyzed from three late Neogene localities in Florida as a proxy for understanding diagenesis in xenarthrans as compared to other mammals. Relative to modern specimens, the fossils have about two orders of magnitude higher concentrations of REE. Uptake rates vary significantly among different dental tissues, i.e., bone > dentine (both inner and outer) > enamel. REE concentrations of fossil vertebrate specimens vary significantly between different localities. The REE Index (ratio of outer dentine/bone or enamel/bone for a given specimen) is proposed here to evaluate relative diagenesis in xenarthrans and other mammals, respectively. Other (non-xenarthran) mammals tend to have a lower REE Index, interpreted to represent less diagenesis. Nevertheless, many xenarthrans likewise have a low REE Index relative to other mammals at the same locality, indicating a similar degree of diagenesis. While the REE Index will likely be a reliable indicator of relative diagenesis in xenarthrans, the outer dentine provides challenges to the ultimate goal of interpreting proxy geochemical (e.g., stable isotope) data from these extinct mammals.
Pion yields and pion spectra from nuclear collisions

Abstract Pion yields and pion spectra from collisions of heavy symmetric systems are calculated in a statistical model up to 2 GeV/nucleon beam energy. We use a version of the FREESCO event generator that includes the Δ-resonance, Coulomb effects and recently developed description of the collective flow and transparency. Results are compared to available data and the applicability and limitations of the statistical treatment are studied. We point out the need for dynamical effects to explain the two-temperature shape of the pion spectra.
Similarities between Exogenously- and Endogenously- Induced Envelope Stress: The Effects of a New Antibacterial Molecule, TPI1609-10

Antibiotics with novel and/or multiple targets are highly desirable in the face of the steady rise of clinical antibiotic resistance. We have screened and identified small molecules, typified by the compound TPI1609-10 (aka SM10), with antibiotic activity against both gram-positive and gram-negative bacteria. SM10 was screened in vitro to bind branched Holliday junction intermediates of homologous recombination and tyrosine recombinase-mediated recombination; thus, the cellular targets of the small molecules were expected to include the RuvABC Holliday junction resolvasome and the XerCD complex involved in proper segregation of replicated chromosomes to daughter cells. SM10 indeed induces DNA damage and filamentation in E. coli. However, SM10 also induces envelope stress and causes increased production of intracellular reactive oxygen species. In addition, SM10 has similar effects to endogenously-induced envelope stress via overproducing outer membrane proteins (OmpC and OmpF), which also induces the SOS response, chromosome fragmentation, and production of reactive oxygen species. The synergy between SM10, and cerulenin, a fatty acid synthesis inhibitor, together with the SM10 hypersensitivity of cpx and rpoE mutants, further support that SM10's mode of action damages membrane damage. The lethality of SM10 treatment and of OmpC overproduction are observed in both aerobically- and anaerobically-grown cells, and is accompanied by substantial DNA damage even anaerobically. Thus, only some DNA damage is due to reactive oxygen. We propose that membrane depolarization and the potential reduction in intracellular pH, leading to abasic site formation, cause a substantial amount of the DNA damage associated with both SM10 treatment and endogenous envelope stress. While it is difficult to completely exclude effects related to envelope damage as the sources of DNA damage, trapping intermediates associated with DNA repair and chromosome segregation pathways remains very likely. Thus SM10 may have distinct but synergistic modes of action.
Fragaria: A genus with deep historical roots and ripe for evolutionary and ecological insights

The cultivated strawberry, Fragaria ×ananassa, is one of the youngest domesticated plants. Its 18th century origin via hybridization in Europe between the North American F. virginiana and the South American F. chiloensis was documented by the botanist Antoine Nicolas Duchesne. His 1766 "Natural History of Strawberries" is an extraordinary work that integrates fundamental discoveries on the biology, ecology, and phylogeny of Fragaria with applied information on cultivation and ethnobotanical uses, serving as an inspiration for current research in the genus. Fragaria species exhibit the full range of sexual systems in the gynodioecy pathway from hermaphroditism to dioecy (and back again), as well as variation in self-compatibility, and evidence of sex chromosomes with female heterogamety. The genus is also characterized by interspecific hybridization and polyploidy, with a natural range of ploidy levels from diploids to decaploids. This biological diversity, combined with the availability of genomic resources and the ease of growing and experimenting with the plants, makes Fragaria a very attractive system for ecological and evolutionary genomics. The goal of this review is to introduce Fragaria as a model genus and to provide a roadmap for future integrative research. These research directions will deepen our understanding of the ecological and evolutionary context that shaped the ancestors of the cultivated strawberry, not only providing information that can be applied to efforts to shape the future of this important fruit crop but also our understanding of key transitions in plant evolution.
ENVIRONMENTAL EFFECTS OF THE PAC BARONESS OIL AND COPPER SPILL

ABSTRACT A study was conducted to investigate the initial environmental effects of an offshore oil and copper spill resulting from the sinking of the freighter Pac Baroness approximately 19 kilometers (km) southwest of Point Conception, California, at a water depth of 430 meters (m). Gas chromatography with mass spectrometry detection (GC/MS) was used to examine the distribution and levels of hydrocarbons in surficial sediments and to compare patterns of hydrocarbons in the sediments to those of a source-oil sample obtained from the vessel. Potential impacts of the spill on macroinfauna were also evaluated by examining changes in community structure and composition and in abundances of component species, based on comparison between control and wreck-site samples. Results of the chemical analyses show that sediment samples collected in the vicinity of the Pac Baroness contain elevated levels of hydrocarbons and other petroleum components that clearly originate from the oil on board the sunken vessel. Stati...
Using naphthalene-2-thiolate ligands in the design of hydrogenase models with mild proton reduction overpotentials

Abstract Diiron–carbonyl complexes coupled to naphthalene-2-thiolate ligands, [(μ-naphthalene-2-thiolato)2Fe2(CO)6] (1) and [(μ-naphthalene-2-thiolato)2Fe2(CO)5PPh3] (2), have been usefully prepared and structurally characterized. As models for the active site of hydrogenase enzymes, these compounds have been examined as electrocatalysts for the reduction of proton to produce molecular hydrogen. In the presence of acetic acid, 1 and 2 catalyze the electrochemical production of molecular hydrogen with mild overpotentials of −0.54 and −0.51 V versus Fc/Fc+, respectively. The overpotential for compound 1 is 260 mV smaller than that of the analogous compound, [(μ-SPh)2Fe2(CO)6].
Amrinone preconditioning in the isolated perfused rabbit heart.

Abstract Background . Ischemic preconditioning (IPC) reduces infarct size in experimental preparations. IPC, however, is not without detrimental effects. We studied amrinone as a possible alternative to IPC. Methods . Isolated perfused rabbit hearts were given a 5-minute infusion of 10 μmol/L amrinone followed by a 5-minute washout (n = 6). The anterior descending artery was then occluded for 1 hour and reperfused for 1 hour. Six hearts underwent IPC, with two episodes of 5-minute global ischemia followed by 5-minute reperfusion before LAD occlusion; eight control hearts received no preconditioning. Left ventricular pressure and ischemic zone epicardial monophasic action potentials were continuously monitored. Results . IPC but not amrinone reduced peak pressure before anterior descending artery occlusion. Peak pressure fell significantly during ischemia and reperfusion in all hearts. End diastolic pressure rose significantly during reperfusion in control and IPC hearts but not in amrinone hearts. Action potentials shortened during ischemia in all hearts. They returned to preocclusion values in control hearts but lasted beyond preocclusion values in IPC and amrinone hearts. Both the incidences of ventricular fibrillation and infarct size were significantly reduced in amrinone hearts but not in IPC hearts. Conclusions . Amrinone is not only a useful inotropic agent but is also a superior preconditioning agent when compared to IPC.
Cardiac transplantation for the treatment of adults with congenital heart disease: a single center experience

patients who had an ICD placed for ventricular tachycardia or syncope with known left ventricular dysfunction and/or severe transplant coronary artery disease (TCAD). Methods: Six heart transplant patients with symptoms of left ventricular dysfunction and/or severe TCAD by angiography presented with syncope or non-sustained ventricular tachycardia on cardiac monitoring. Due to the implied risk of sudden death, these patients underwent percutaneous ICD placement [Medtronic (2), Guidant, Atlas, Ventak, CPI]. Results: The average age of the six patients was 58 years and the average time to ICD after heart transplant was 82 months (range 53 to 155 months). 4/5 patients had reduced echo left ventricular ejection fraction between 18 and 45% and 5/6 patients had severe 2 to 3 vessel TCAD. 2/6 patients died suddenly within four months of having the ICD placed. The two patients had progression of TCAD at absaopsy. The four remaining patients have had no firing of the ICD and have had routine ICD follow-up. The longest patient has had the ICD for 65 months with progression of his TCAD. Conclusion: ICD placement does not necessarily protect heart transplant patients from sudden death especially if they have progression of underlying TCAD. Further experience with ICD in heart transplant patients is needed prior to establishing a policy regarding the use of this life saving device.
Motor Vehicle Crashes: The Association of Alcohol Consumption with the Type and Severity of Injuries and Outcomes

The effect of alcohol ingestion on short-term outcomes for trauma patients is indeterminate. Experimental and clinical reports often conflict. The objective of this study was to investigate the prevalence of positive alcohol screens, the effect of alcohol ingestion on injury patterns, severity, and outcomes in patients who were involved in motor vehicle crashes (MVC). MVC patients aged > 10 years treated in any of the 13 trauma centers in Los Angeles County during the calendar year 2003 were studied. All patients underwent routine alcohol screening on admission. The alcohol negative group ("no ETOH") had a blood alcohol level (BAL) of 0.005 g/dL to or = 0.08 g/dL, respectively. Logistic regression was performed to compare injury severity, complications, survival, and length of hospital stay among the three groups. Of the 3025 patients studied, 2013 (67%) were in the no ETOH group, 216 (7%) were in the low ETOH group, and 796 (26%) were in the high ETOH group. Levels were not associated with injury severity, Emergency Department hypotension, or Intensive Care Unit length of stay. Patients with an injury severity score > 15 and a high BAL had a higher incidence of severe head trauma (head abbreviated injury score > 3) and increased incidence of sepsis. However, in this group of severely injured, the high ETOH group had a significantly better survival rate than patients in the no ETOH group (adjusted odds ratio 0.41, 95% confidence interval 0.16-0.94, p = 0.05). Severely injured MVC victims with a high BAL have a higher incidence of severe head trauma and septic complications than no ETOH patients. However, the high ETOH group had superior adjusted survival rates.
Limitation of podocyte proliferation improves renal function in experimental crescentic glomerulonephritis

Limitation of podocyte proliferation improves renal function in experimental crescentic glomerulonephritis. Background Many forms of glomerular diseases are characterized by injury to the glomerular visceral epithelial cell, or podocyte, which usually results in depletion of podocyte number. However, in diseases where podocyte proliferation occurs there is a rapid decline in renal function. The consequences of inhibiting podocyte proliferation on renal function have not been fully established. At the level of the cell cycle, cyclin-dependent kinase 2 (CDK2) is required for proliferation. Methods To determine if decreasing podocyte proliferation improves renal function, CDK2 activity was reduced with the purine analogue roscovitine in mice with antibody-induced experimental glomerulonephritis. Nephritic animals given vehicle, dimethyl sulfoxide (DMSO), served as control. Blood urea nitrogen (BUN), proteinuria, and renal histology were assessed at days 5 and 14 of disease. Results Inhibiting CDK2 activity resulted in a marked decrease in glomerular DNA synthesis [5-bromo-2′-deoxyridine (BrdU) staining] in Roscovitine-treated animals at day 5 of nephritis ( P P P Conclusion Inhibiting podocyte proliferation in experimental glomerulonephritis is associated with improvement in renal function and histology, suggesting that inhibiting CDK2 activity is a potential therapeutic target for glomerular diseases characterized by podocyte proliferation.
Manufacture of 21 MB Floptical disk using acousto-optically controlled laser ablation process

Iomega decided that be developing our own Floptical media production equipment, we could enhance the basic Floptical technology with our servowriting experience and capabilities acquired from our own patented BernoulliTM Box magnetic storage technology. This technology synthesis has led to our proprietary laser ablation servowriting equipment for magnetic media. This system has been dubbed LightSaberTM.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Institutional core values: operationalising the constructs

This research begins to operationalise eight institutional core values at a mid‐sized, Midwestern Catholic university. The survey sought examples of ways in which the graduate students in a master of arts in teaching and leadership programme had and/or had not experienced the institutional core values with the same professor during their four‐course research sequence. The 55 respondents (26% rate) yielded 220 comments contributing to at least three themes for each core value. The results did begin the process of operationlising the core values, while educational best practice was layered through and among the themes. Though generalisation to other populations is not an intended outcome of this research, the 26% return rate and potential responder bias were identified as two possible limitations. Among other ideas, future research is suggested to include additional graduate students and undergraduate students from all disciplines and a variety of faith‐based institutions.
Supramolecular Pseudorotaxane Polymers from Complementary Pairs of Homoditopic Molecules

Self-assembly of supramolecular pseudorotaxane polymers from complementary homoditopic building blocks comprised of bis(dibenzo-24-crown-8) esters derived from the hydroxymethyl crown ether and aliphatic diacid chlorides (CxC, x = number of methylene units in the diacid segment) and 1,10-bis[p-(benzylammoniomethyl)phenoxy]alkane bis(hexafluorophosphate)s (AyA, y = number of methylene units in the linker) has been studied. 1H NMR spectroscopic studies of bis[(2-dibenzo-24-crown-8)methyl] sebacate (C8C) with dibenzylammonium hexafluorophosphate (6) showed that the two binding sites of the ditopic host are equivalent and independent (no positive or negative cooperativity). Likewise the binding sites in 1,10-bis[p-(benzylammoniomethyl)phenoxy]decane bis(hexafluorophosphate) (A10A) were shown to behave independently with dibenzo-24-crown-8 (1a). Then using 1H NMR spectroscopy on dilute equimolar solutions (<1 mM) of CxC and AyA association constants were estimated for the formation of the linear (lin-CxC•AyA) ...
Finding effective ways to teach non-traditional students: A different model of teaching and learning

As the education landscape continues to evolve, non-traditional students are becoming a growing number in the demographics of college graduates. Many of these students, including working professionals, adult learners, and first generation college goers, start their education at a community college and later transfer to a four-year institution to finish their bachelor's degree. Juggling multiple commitments such as jobs and family obligations, lack of access to resources and role models, and a K-12 education that often does not reflect a solid foundation, collectively result in a learning experience that does not align or mirror the standard "college experience" of a traditional student. Yet teaching and instruction techniques have remained the same for this population. In this paper, we will share our experience over the past four years in running a bachelor's degree completion program for such non-traditional students. We will address some of the challenges faced by this group and also some of the innovative ways that we have constructed a curriculum that could connect, inspire, and motivate our students. Our long-term goal is to construct a pedagogical methodology that would better be suited for non-traditional students and to provide a support system that ensures their success.
A market for organs

p ublic awareness of the critical shortage of cadaveric human organs made available for transplantation was recently heightened by the unfortunate case of Mickey Mantle. Mr. Mantle's need for and relatively rapid receipt of a liver transplant brought widespread attention to the plight of thousands of other sufferers of heart, liver, lung, and kidney failure whose lives depend upon timely receipt of a suitable organ for transplantation. It also brought considerable suspicion and outright scorn regarding the integrity of the current system used to allocate these scarce organs among the growing pool of patients needing them. Disputes about allocation issues, however, tend to have the undesirable effect of diverting attention away from the more serious topic of devising public policies that will ultimately resolve the organ shortage. If the shortage problem is eliminated, allocation issues become moot. Consequently, the principal message that should emerge from Mr. Mantle's case is not one involving the fairness of the system used to allocate those organs that are procured. Rather, it is that our current public policy has failed miserably to address the organ shortage. And that failure, in turn, has caused needless suffering and death. Rather than begrudging Mr. Mantle his transplant, we should seek out new public policies that will deliver the gift of life to others as well. In this essay, we propose an alternative public policy that, we believe, is capable of fully resolving the organ shortage. This policy relies upon the powerful incentives provided by free market forces to bring forth the additional supply of organs required to meet demand. We compare this policy--organ markets-to the major policy alternatives currently under discussion and find that, in every case, the performance properties of the market system dominate. We also consider both the economic and ethical arguments that have been raised in opposition to organ markets and find each of them to be demonstrably specious. As a result, we conclude that the current legal restriction on the purchase and sale of cadaveric organs should be lifted. This relatively simple "alteration of our public policy would eliminate the organ shortage and, thereby, save thousands of lives each year.
Conical foil x-ray telescope performance predictions for space astronomy applications

In this paper, conical foil x-ray telescope technology is reviewed and performance predictions of the Danish Space Research Institute XSPECT telescope design are conducted. Analysis includes discussion of geometrical aberrations, diffraction effects, assembly and alignment errors, and optical fabrication errors. NASA's Optical Surface Analysis Code and Encircled Energy for Grazing incidence optics computer codes are used to predict geometrical performance and model degradation effects of residual surface irregularities. Results are incorporated into a system error budget and parametric image quality predictions are performed. Finally, a summary of image quality predictions and an evaluation of conical foil telescope technology for space astronomy applications are presented.
Fiber Optic Guided Functional Electrical Stimulation with Microscale Photovoltaic Neurostimulator Devices

We report on study of optically activated functional electrical stimulation using a high efficiency microscale photovoltaic device as a neuro stimulator, integrated with a biocompatible, lossless, interference-free glass optical fiber for signal and energy transport.
Electromagnetic scattering from two dielectric spheres: further comparisons between theory and experiment.

Results of experimental measurements and theoretical calculations concerning the scattering of plane wave radiation by a system of two interacting spheres are presented. In particular, the complex scattering amplitude of such a system and the phenomena of specular resonances are addressed. Preliminary calculations of the two-sphere Muller matrix are also considered.
Tests of a heterogeneous bidders theory of first price auctions

Abstract This paper reports the results of eight first price sealed bid auction market experiments using cash motivated subjects to test a constant relative risk averse model (CRRAM) of equilibrium bidding behavior of heterogeneous bidders.
Comparison of low-density lipoprotein modification by myeloperoxidase-derived hypochlorous andhypobromous acids

Abstract Myeloperoxidase (MPO), a heme enzyme secreted by activated phagocytes, catalyzes the oxidation of halides to hypohalous acids. At plasma concentrations of halides, hypochlorous acid (HOCl) is the major strong oxidant produced. In contrast, the related enzyme eosinophil peroxidase preferentially generates hypobromous acid (HOBr). Since reagent and MPO-derived HOCl converts low-density lipoprotein (LDL) to a potentially atherogenic form, we investigated the effects of HOBr on LDL modification. Compared to HOCl, HOBr caused 2–3-fold greater oxidation of tryptophan and cysteine residues of the protein moiety (apoB) of LDL and 4-fold greater formation of fatty acid halohydrins from the lipids in LDL. In contrast, HOBr was 2-fold less reactive than HOCl with lysine residues and caused little formation of N-bromamines. Nevertheless, HOBr caused an equivalent increase in the relative electrophoretic mobility of LDL as HOCl, which was not reversed upon subsequent incubation with ascorbate, in contrast to the shift in mobility caused by HOCl. Similar apoB modifications were observed with HOBr generated by MPO/H2O2/Br−. In the presence of equivalent concentrations of Cl− and Br−, modifications of LDL by MPO resembled those seen in the presence of Br− alone. Interestingly, even at physiological concentrations of the two halides (100 mM Cl−, 100 μM Br−), MPO utilized a portion of the Br− to oxidize apoB cysteine residues. MPO also utilized the pseudohalide thiocyanate to oxidize apoB cysteine residues. Our data show that even though HOBr has different reactivities than HOCl with apoB, it is able to alter the charge of LDL, converting it into a potentially atherogenic particle.
A framework for specifying group decision-making mechanisms

Collaborating agents need to make group decisions to establish their initial commitment to a proposed group activity [8] and, once committed, to coordinate the updating of their intentions related to that activity [6]. (We call the first sort context-free group decisions and the latter context-bound.) In addition, collaborating agents must be able to reason effectively about their participation in group decision-making processes.
Psychopharmacology during pregnancy

Abstract When major psychiatric illness accompanies pregnancy, it is important to weight the risks of prescribing medication against the risks of withholding medication. This article summarizes available data about the risks of untreated psychiatric disorders and the risks of commonly used psychopharmacologic agents during pregnancy. Potential risks of the latter include morphologic teratogenicity, behavioral teratogenicity, fetal and neonatal toxicity, neonatal withdrawal, and effects on the pregnant woman. Certain prescribing practices can minimize the possible risks. These include using nonpharmacologic psychiatric interventions in cases in which they are effective, supplementing specific nutritional elements, finding the minimum effective dose, avoiding certain drug combinations when possible, tapering doses gradually for pregnant women and neonates, and using pharmacologic antagonists to reverse toxicity. Patient education about the additive risks of alcohol drinking, cigarette smoking, stress, poor nutrition, and lack of prenatal care can also improve outcome. Discussing treatment options in detail will help pregnant patients make informed choices about psychopharmacology during pregnancy.
Phosphodiesterase 8A (PDE8A) regulates excitation-contraction coupling in ventricular myocytes

Abstract In ventricular myocytes, activation of protein kinase A (PKA) by 3'-5' cyclic adenosine monophosphate (cAMP) increases the force of contraction by increasing L-type Ca2+ channel currents (ICa) and sarcoplasmic reticulum (SR) Ca2+ release during excitation–contraction coupling. Cyclic-nucleotide phosphodiesterases (PDEs) comprise a large family of enzymes whose role in the cell is to regulate the spatial and temporal profile of cAMP signals by controlling the degradation of this second messenger. At present, however, the molecular identity and functional roles of the PDEs expressed in ventricular myocytes are incompletely understood. Here, we tested the hypothesis that PDE8A plays a critical role in the modulation of at least one compartment of cAMP and hence PKA activity during β-adrenergic receptor (βAR) activation in ventricular myocytes. Consistent with this hypothesis, we found that PDE8A transcript and protein are expressed in ventricular myocytes. Our data indicate that evoked [Ca2+]i transients and ICa increased to a much larger extent in PDE8A null (PDE8A−/−) than in wild-type (WT) myocytes during β-adrenergic signaling activation. In addition, Ca2+ spark activity was higher in PDE8A−/− than in WT myocytes. Our data indicate that PDE8A is a novel cardiac PDE that controls one or more pools of cAMP implicated in regulation of Ca2+ movement through cardiomyocyte.
Light-induced EPR spectra of reaction centers fromRhodobacter sphaeroides at 80 K: Evidence for reduction of QB by B branch electron transfer in native reaction centers

Photosynthetic reaction centers (RCs) fromRhodobacter sphaeroides capture solar energy by electron transfer from primary donor D to quinone acceptor QB through the active A branch of electron acceptors. The light-induced electron paramagnetic resonance (EPR) spectrum from native RCs that had Fe2+ replaced by Zn2+ was investigated at cryogenic temperature (80 K, 35 GHz). In addition to the light-induced signal due to the formation of D+.QA−. observed previously, a small fraction (ca. 5%) of the signal displayed very different characteristics. The signal was absent in RCs in which the QB was displaced by the inhibitor stigmatellin. Its decay time (τ=6 s) was the same as observed for D+.QB−. in mutant RCs lacking QA, which is significantly slower than for D+.QA−. (τ=30 ms). Its EPR spectrum was identical to that of D+.QB−.. The quantum efficiency for forming the major component of the signal was the same as that found for mutant RCs lacking QA (ϕ=0.2%) and was temperature independent. These results are explained by direct photochemical reduction of QB via B branch electron transfer in a small fraction of native RCs.
Analysis of heterogeneity in daunorubicin uptake by human leukemia cells using laser flow cytometry

Heterogeneity in daunorubicin uptake by leukemic blast cells obtained from the bone marrow of 16 patients with acute leukemia (10 acute nonlymphocytic leukemia and 6 acute lymphocytic leukemia) was determined by laser flow cytometry following drug treatment in vitro for 1 hr. Fluorescence profiles of cellular anthracycline levels in the various samples indicated a marked heterogeneity in daunorubicin uptake and the range of detectable drug fluorescent cells was 34% – 99%. A retrospective analysis of disease outcome in these patients who were treated with a daunorubicin or doxorubicin containing induction regimen indicated the following: (a) 8 of 11 patients who entered complete remission had > 80% of leukemic blast cells accumulating detectable amounts of daunorubicin; and (b) 3 of 4 patients who did not respond to chemotherapy had < 40% of the leukemic blast cells accumulating detectable amounts of daunorubicin. These results suggest that laser flow cytometry may be useful in determining qualitative and quantitative differences in daunorubicin levels in heterogeneous tumor cell populations.
Localized urethral cancer in women

The results of treatments for localized carcinoma of the urethra were assessed in 21 consecutive women treated at our institutions over a twenty year period. Only one of the tumors was confined to the distal urethra. Eighty-six percent invaded the periurethral tissues and 24% were known to be associated with regional lymph node metastases. Fifty-seven percent were adenocarcinomas. Five patients refused active therapeutic intervention and expired within one to 30 months following diagnosis. Sixteen patients were treated with extirpative surgery, radiation therapy, or combinations of the two. Four are free of disease at one, four, eleven, and 15 years after treatment. Nine developed pelvic recurrences, two developed pelvic recurrences and distant metastases and one developed distant metastases only from six to 72 months (mean, 19 months) after initial treatment. Eight of these 12 patients died at two to 13 months (mean, 8 months) after secondary treatment, two are alive with residual pelvic tumor, and two are clinically free of disease at 7 and 48 months. Only six patients were known to have distant metastases at the time of death and five of these six had adenocarcinomas. Advanced localized urethral cancer in women is difficult to eradicate and usually fatal.
Simple Analytical Dual-Band Spectral-Spatial RF Pulses for B1+ and Susceptibility Artifact Reduction in Gradient Echo MRI

Susceptibility artifacts and transmission radio frequency (RF) field (B(1) +) inhomogeneity are major limitations in high-field gradient echo MRI. Previously proposed numerical 2D spectral-spatial RF pulses have been shown to be promising for reducing the through-plane signal loss susceptibility artifact by incorporating a frequency-dependent through-plane phase correction. This method has recently been extended to 4D spectral-spatial RF pulse designs for reducing B(1) + inhomogeneity as well as the signal loss. In this manuscript, we present simple analytical pulse designs for constructing 2D and 4D spectral-spatial RF pulses as an alternative to the numerical approaches. The 2D pulse capable of exciting slices with reduced signal loss and is lipid suppressing. The 4D pulse simultaneously corrects signal loss as well as the B(1) + inhomogeneity from a body coil transmitter. The pulses are demonstrated with simulations and with gradient echo phantom and brain images at 3T using a standard RF body coil. The pulses were observed to work well for multiple slices and several volunteers.
Technique To Improve Visualization Of Elusive Tree-Ring Boundaries In Aspen (Populus tremuloides)

Abstract A simple, quick, and inexpensive technique to improve visualization of aspen (Populus tremuloides) tree rings under the microscope, the ‘shadow technique’, is described. The technique assumes appropriate preparation of increment cores or cross-sections and works well on the lighter portions of the sample with fungus- and bacteria-free wood. The shadow technique was used successfully to elucidate tree-ring boundaries in small diameter ( 100 annual rings. Crossdating verified whether the elusive rings were missing or false rings. Aspen tree-ring measurement will be greatly enhanced with the shadow technique and preliminary investigation suggests it could be used on other species such as curlleaf mountain mahogany (Cercocarpus ledifolius).
A multilevel control bulk queueing system with vacationing server

This article studies a Markov chain describing the evolution of the queue in a general single-server bulk queueing system with continuously operating (or, equivalently vacationing) server, semi-Markov modulated compound Poisson input, queue length dependent service time, and multilevel control server capacity. We establish a necessary and sufficient criterion for ergodicity of this Markov chain and find its stationary distribution. As an example a single-server queueing system is considered, and some explicit results are obtained in this case.
How many patients with severe sepsis are needed to confirm the efficacy of drotrecogin alfa activated? A Bayesian design.

Objectives Controversies concerning the pivotal trial and negative results from other Drotrecogin alfa activated (DAA) trials have raised questions about its efficacy in severe sepsis patients. Based on all available evidence, our study aimed to respond to: (1) What is the current probability that DAA is not better than the control? If the current probability is not small, e.g. greater than 0.05, then (2) How many patients will be needed for the DAA confirmatory trial?
Metabolism of benzo(a)pyrene to reactive intermediate(s) via prostaglandin biosynthesis.

Abstract We have examined the oxidation of benzo (a) pyrene (BP) to electrophilic metabolites during the formation of prostaglandins (PG) and thromboxanes (TX) from arachidonic acid (AA) by guinea pig lung microsomal protein. In the presence of NADPH or AA, electrophilic metabolites of [14C]-BP were generated which were non-extractable from microsomal protein and thus assumed to be covalently bound. The total amount of BP metabolized in the presence of NADPH was 2–2 1 2 times the amount of BP metabolized in the presence of AA. Only 4–5% of BP metabolized by the NADPH mediated mixed-function oxidase system was covalently bound, whereas 12–15% of the BP metabolized in the presence of AA was covalently bound to tissue protein and DNA. Quinones were the major metabolites produced by the AA dependent system, while dihydrodiols were the major metabolites formed by the NADPH dependent system. 7, 12-Dimethyl-benzanthracene, and 7,8-BP-dihydrodiol, but not 3 hydroxy-BP were also oxidized by PG synthetase to reactive metabolites.