cssi/SciSciGPT-SciSciNet huggingface dataset:
Reactive oxygen species generated by PAH o-quinones cause change-in-function mutations in p53.

Polycyclic aromatic hydrocarbons (PAHs) in tobacco smoke may cause human lung cancer via metabolic activation to ultimate carcinogens. p53 is one of the most commonly mutated tumor suppressor genes in this disease. An analysis of the p53 mutational database shows that G to T transversions are a signature mutation of lung cancer. Aldo-keto reductases (AKRs) activate PAH trans-dihydrodiol proximate carcinogens to yield their corresponding reactive and redox-active o-quinones, e.g., benzo[a]pyrene-7,8-dione (BP-7,8-dione). We employed a yeast reporter system to determine whether PAH o-quinones or the ROS they generate cause change-in-function mutations in p53. N-Methyl-N-nitroso-N'-nitro-guanidine, a standard alkylating mutagen was used as a positive control. MNNG caused a dose-dependent increase in mutant yeast colonies and at the highest concentrations 8-14% of the yeast colonies were mutated and were characterized by G:C to A:T transitions in the p53 DNA binding domain. Treatment of p53 cDNA with micromolar concentrations of (+/-)-anti-7,8-dihydroxy-9alpha,10alpha-epoxy-7,8,9,10-tetrahydro-benzo[a]pyrene, (anti-BPDE, an ultimate carcinogen) or sub-micromolar concentrations of BP-7,8-dione in the presence of redox-cycling conditions (NADPH and CuCl(2)) also caused p53 mutations in a dose-dependent manner. We found that no mutants were observed with PAH o-quinones or NADPH alone. p53 mutagenesis by BP-7,8-dione was attenuated by ROS scavengers and completely abrogated by a combination of superoxide dismutase and catalase, indicating that both superoxide anion and hydroxyl radicals were the responsible mutagens. The bulk of the mutations detected were single-point mutations and were not random in occurrence. Over 46% of BP-7,8-dione-induced mutations were G:C to T:A transversions, consistent with the formation of 8-oxo-dGuo or its secondary oxidation products. In addition, 25% of these mutations were at hotspots in p53 which are known to be mutated in lung cancer. Together these data suggest that PAH o-quinones generate an endogenous mutagen (ROS) which leads to p53 inactivation. These observations provide an alternative route to G to T transversions that dominate in p53 in lung cancer.
Cantonese: Basic Course

30 lessons including dialogues for conversation practice, pronunciation and grammar explanations, practice drills, vocabulary listings, etc.
A contemporary evaluation of cytoreductive nephrectomy with tumor thrombus: Morbidity and long-term survival.

Abstract Background: Metastatic renal cell carcinoma (RCC) is an aggressive entity that frequently invades the venous system. We evaluated the morbidity and survival of patients with tumor thrombus who undergo cytoreductive nephrectomy. Materials and methods: We identified 56 patients from our institution’s database who had a primary renal tumor in place and documented metastases at the time of surgery. We reviewed demographic and pathologic characteristics from these patients as well as complications and overall survival. Results: Median age was 58 (37–77). There were 33 patients (59%) who had tumor thrombus with 21 (64%) involving the renal vein, 10 (30%) involving the infradiaphragmatic inferior vena cava (IVC), and 2 (6%) involving the supradiaphragmatic IVC. Median tumor size for thrombus patients was 12 cm (5–29). There were 8 (14.2%) who had complications, including 1 death. Thrombus patients were significantly more likely to have a complication ( P = 0.008). Median survival for all patients was 10.7 months (0.3–61). There was no significant difference in overall survival between patients with and without thrombus ( P = 0.76). Conclusions: Patients who undergo cytoreductive nephrectomy with a tumor thrombus have a higher rate of complications as compared to patients undergoing cytoreductive nephrectomy without tumor thrombus. The long-term survival, however, was not statistically different and thus aggressive surgery for select metastatic RCC patients is warranted.
A family of 3D continuously differentiable finite elements on tetrahedral grids

A family of continuously differentiable piecewise polynomials of degree 9 and higher, on general tetrahedral grids, is constructed, by simplifying and extending the P"9 element of Zenisek. A mathematical justification and numerical tests are presented. The current computing power is still limited for the computation with 3D C"1 finite elements in general. The construction here mainly serves the purposes of understanding and ensuring the approximation properties of C"1 finite elements spaces on tetrahedral grids. In particular, this construction indicates that the 3D divergence-free C"0-P"k elements have the full order of approximation for any degree k>=8.
Chronic Pain, Physical Symptoms, and Type a Behavior in Young Adults

7 subjects (mean age of 27 yr.) who complained of chronic pain symptoms were compared to seven age- and sex-matched controls on the following variables: number of physical symptoms, Type A tendency...
Using Economic Input-Output Life Cycle Assessment to Guide Sustainable Design

Successful design for the environment (DfE) requires the designer to understand the life cycle impact of design decisions. However, estimating life cycle implications of design choices using traditional process-based life cycle assessment (LCA) is typically too time- and resource-intensive to be practical as part of the design process. We examine the use of economic input-output life cycle assessment (EIO-LCA) as a tool to support sustainable design by helping the designer to quickly determine which aspects of the product dominate its lifetime emissions. Compared to traditional process-based LCA, EIO-LCA produces estimates at a more aggregated level using data on economic transactions and emissions from each sector of the economy. However, EIO-LCA computes full supply chain emissions associated with output from a particular sector in seconds, and for many products these aggregate-level data are sufficient to determine which aspects of the product dominate and to guide sustainable design efforts. We explore two product design examples where a quick scoping exercise with EIO-LCA identifies clear areas of focus for design improvement and innovation.Copyright © 2011 by ASME
Sensation Seeking and Cortical Augmenting-Reducing

The experiment was designed to establish the relationship between the Sensation Seeking Scales (SSS) and cortical augmenting-reducing. Forty-nine male undergraduate Ss were used. Ss were presented with five intensities of light flashes in randomly presented blocks of trials at each intensity. Averaged evoked response (AER) amplitudes were measured at each intensity of light. Augmenting-reducing was measured for each S as the slope of the relationship between stimulus intensity and amplitude of response. This slope measure correlated very significantly (r= .59) with the Disinhibition subscale of the SSS and positively, but not significantly, with other subscales. Comparing the low and high scorers on the Disinhibition scale, a significant interaction between groups and stimulus intensities was found but no main effects of stimulus intensity or groups were found. The high Disinhibitors did not differ from the lows at the low stimulus intensities but did differ significantly at the highest intensity where the lows showed a marked reducing tendency. The results show an interesting convergence between the Disinhibition type of sensation seeking, manic tendencies, and the AER.
An Experimental Investigation of Relativistic Effects in GPS

Relativistic corrections have been implemented for the GPS satellites to account for time dilation and difference in gravitational potential for satellite clocks with respect to clocks on the earth. No similar corrections are known to be made for GPS receivers on dynamic platforms. This paper presents an investigation into the relativistic effects proposed in [I/. It is shown that two of the three terms affecting the receiver clock proposed in [ll are satellite dependent, a result that is not borne out by experimental data. This finding supports the conclusion in [2] that there are no differences among the earth- centered, earth-fisted (ECEF), earth-centered inertial (ECI,,, and topocentric reference frames as long as the appropriate transformations are applied.
Alteration of Systolic Time Intervals in Right Ventricular Failure

Systolic time intervals (STI) were measured in matched patients with and without right ventricular failure (RVF). STI were calculated from brachial arterial pressure tracings obtained at cardiac catheterization in four groups of patients: 1) controls, without RVF; 2) acute pulmonary embolism with and without acute RVF; 3) mitral stenosis, with and without chronic RVF; 4) primary pulmonary hypertension, with chronic RVF. In patients with pulmonary embolism without acute RVF, STI were normal. However, patients with acute RVF due to pulmonary embolism had significantly shortened left ventricular ejection times (LVETc) and significantly increased pre-ejection periods (PEPc) and increased PEPc/LVETc ratios (P < 0.05, P < 0.001, P < 0.001 respectively). Similar results were obtained in patients with chronic RVF. In patients with mitral stenosis without RVF, STI were normal. However, in patients with chronic RVF due to mitral stenosis or primary pulmonary hypertension, PEPc and PEPc/LVETc ratios were lengthened ...
Skin color constancy for illumination invariant skin segmentation

Accuracy of skin segmentation algorithms is highly sensitive to changes in lighting conditions. When the lighting condition in a scene is different from that in the training examples, miss-classification rate of the skin segmentation algorithms is high. Using color constancy approach we aim to compensate for skin color variations to achieve accurate skin color segmentation. Skin color constancy is realized in an unsupervised manner by using the color changes observed on a face for different illuminations to drive the model. By training on few faces of different ethnicities, our model is able to generalize the color mapping for any unseen ethnicity. The color changes observed are used to learn the color mapping from one lighting condition to the other. These mappings are represented in a low dimensional subspace to obtain basis vector fields. Using these basis vector fields we can model the nonlinear color changes to transform skin colors in arbitrary lighting conditions to a reference lighting condition. We show the proof of concept of unsupervised skin color constancy on faces from the PIE database. Skin segmentation is performed on the color compensated faces using a Skin Distribution Map (SDM), which is trained on skin colors in reference lighting condition.
An orthotopic, postsurgical model of luciferase transfected murine osteosarcoma with spontaneous metastasis

Osteosarcoma (OS) is the most common bone tumor in humans. Newer, more clinically relevant models of OS are required to investigate novel therapeutics. The ability to study spontaneous micrometastases in the absence of a primary tumor is important since this is the manner in which most patients are treated clinically. Therefore, we have developed a novel model of murine OS using the DLM8 cell line, which is syngeneic to C3H mice. We have engineered these cells to express firefly luciferase so the development of metastases can be followed serially and non-invasively. These cells form osteolytic/osteoproductive lesions and metastasize spontaneously after orthotopic implantation in the proximal tibia, and the development of soft-tissue metastasis can be followed serially by luciferase expression following amputation. We have demonstrated a significant prolongation of disease-free and overall survival in the surgical adjuvant setting following treatment with doxorubicin or carboplatin, drugs which form the mainstay of treatment for human OS. In conclusion, we have developed a novel surgical adjuvant model of metastatic OS in immunocompetent mice that closely recapitulates the clinical situation, allowing the evaluation of novel therapeutics in the context of minimal residual disease.
Design, Synthesis, Structure, and Gas (N2, Ar, CO2, CH4, and H2) Sorption Properties of Porous Metal-Organic Tetrahedral and Heterocuboidal Polyhedra

A strategy based on assembling metal ions and organic carboxylate links has been applied for the design and synthesis of a new class of porous, truncated tetrahedral and heterocuboidal polyhedra, whose pore size and functionality can be systematically varied. The synthesis of this series of metal-organic polyhedra (MOPs) employs sulfate-capped oxygen-centered iron-carboxylate trimers, Fe3O(CO2)3(-)(SO4)3, as rigid nodes separated by linear (phenyl, biphenyl, terphenyl, and tetrahydropyrene) or trigonal (benzenetriphenyl) links to yield five highly crystalline polyhedra of general formula [NH2(CH3)2]8[Fe12O4(-)(SO4)12(link)x(py)12].G (x = 6 for linear or 4 for trigonal, py = pyridine, G = guests). In this series, the size of each polyhedron has been varied from 20.0 to 28.5 A (on edge), and the corresponding pore diameter from 7.3 to 13.3 A. Gas sorption isotherms were measured for three members of this series to reveal significant uptake of gases (N2, Ar, CO2, H2, CH4) and benzene and exhibit Type I sorption behavior that is indicative of permanent porosity. The apparent surface areas for these compounds range from 387 to 480 m(2)/g.
Some computationally relevant group theoretic structures of fixed charge problems

Among the most commonly occurring mixed-integer problems in operations research are linear programs with fixed charge objective functions. In this paper special structures of the equivalent form of such problems obtained from optimal solutions to their continuous relaxations are characterized and exploited in a series of penalty procedures for branch-and-bound type algorithms. The selection, construction, and solution of such penalty problems are discussed, and computational experience with the procedures is presented.
Stress and Coping with a Professional Challenge in Entering Masters of Social Work Students: The Role of Self‐Compassion

The study examined the role of religiosity, spirituality, and self‐compassion in responding to a professional stressor among first year masters of social work students. A total of 66 entering students from two masters of social work programs in the western United States participated in a paper‐pencil survey. While religiosity and spirituality did not influence the stress and coping process, self‐compassion did. In particular, multivariate analyses showed that overidentification, a negative component of self‐compassion, was associated with increased stress, while common humanity, a positive component of self‐compassion, was associated with effective coping. Implications of study findings for social work education are discussed.
Modeling Sensible and Latent Heat Transport in Crop and Residue Canopies

Modeling of latent and sensible heat exchange in crop and residue canopies is complicated by the fact that the equations for the two processes are strongly coupled and require simultaneous solution. We derive a set of uncoupled equations where the new fluxes are enthalpy and isothermal latent heat and the new driving forces are equivalent temperature and vapor pressure deficit. The canopy network equations, using the new driving variables, are reduced, using Thevenin's theorem, to a single potential and a single resistance for each flux.
On the role of indium underlays in the prevention of thermal grooving in thin gold films

Abstract Thin gold films are potentially important for metallizations in microelectronic devices because of the high activation energy of gold for electrotransport. A high activation energy ensures a longer lifetime of microelectronic devices compared with those in which aluminum metallizations are used. When electromigration is no longer the principal failure mechanism, other failure mechanisms, caused by d.c. stressing, might become important. One possibility is grain boundary grooving. Preliminary studies have shown that grain boundary grooving in thin gold films is prevented by inserting an indium underlay between the gold film and the substrate. The objective of this work was to investigate the mechanisms for the prevention of grain boundary grooving in In/Au composite films by comparing the microstructural evolution of pure gold films with In/Au composite films during isothermal annealing. Microstructures were characterized in terms of grain size, grain size distribution, preferred orientation and surface morphology utilizing transmission electron microscopy (TEM), cross-sectional TEM, scanning electron microscopy and X-ray diffraction. The chemical reactions and the distributions of the phases were monitored by selected area diffraction in TEM, and by Auger electron spectroscopy sputter profiling. It was found that the principal mechanisms that inhibit grain boundary grooving in IN/Au composite films area as follows. 1. (1) Indium underlays modify the microstructure of gold films by randomizing the orientation of the grains, refining the grain size, narrowing the grain size distribution and roughening the surface of the gold films. 2. (2) Indium is redistributed on gold films and forms In2O3 on the free surface and within the film during air annealing. 3. (3) The In2O3 on the surface “caps” the surface of gold films and limits mass transport during annealing. 4. (4) The In2O3 within the gold film, presumably residing at grain boundaries, impedes grain growth by pinning the grain boundary migration.
Race and prevailing wage laws in the construction industry: Reply to Azari-Rad and Philips

In the Winter 1999 issue of the Journal of Labor Research (“Prevailing Wage Laws and Black Employment in the Construction Industry”), I reported a significant inverse relationship between the strength of states’ prevailing wage laws and the prospects for black employment in the construction industry. My conclusions are challenged by Azari-Rad and Philips in “ Race and Prevailing Wage Laws in the Construction Industry,” in this issue. This reply responds with new evidence reinforcing the previously asserted relationship: black employment ratios in construction are better in states that don’t have prevailing wage laws than in states that do, and they lessen as the strength of those laws increase. Furthermore, prevailing wage law repeal has apparently benefited black employment opportunities in the construction industries of the states where it has occurred.
Rapid purification of cobalamin-binding proteins using immobilized aminopropylcobalamin

Abstract Aminopropylcobalamin (AP-Cbl), prepared from 3-chloropropylamine and cob(I)alamin, was immobilized on CNBr-activated Sephacryl beads. The product, Sephacryl-aminopropylcobalamin, contained ca. 1 μmol of AP-Cbl/ml of beads. Cobalamin-binding proteins in biological fluids were adsorbed selectively and quantitatively by Sephacryl-aminopropylcobalamin. After being washed to remove extraneous protein, the beads were photoirradiated to release the cobalamin-binding proteins as their aquacobalamin complexes. The latter could be converted to labeled cyanocobalamin complexes by treatment with [ 14 C]KCN. The efficacy of this affinity chromatographic method is illustrated by the purification to near homogeneity and in high yield of three representative proteins: transcobalamin II from rabbit serum, intrinsic factor from human gastric juice, and R binder from human saliva.
Long-term outcome of dialysis patients in the United States with coronary revascularization procedures

Long-term outcome of dialysis patients in the United States with coronary revascularization procedures. Background The optimal method of coronary revascularization in dialysis patients is controversial, as previous small retrospective studies have reported increased cardiac events after percutaneous transluminal coronary angioplasty (PTCA) compared with coronary artery bypass (CAB) surgery. The purpose of this study was to compare the long-term survival of chronic dialysis patients in the United States following PTCA or CAB surgery. Methods Dialysis patients hospitalized from 1978 to 1995 for first coronary revascularization procedure after initiation of renal replacement therapy were retrospectively identified from the United States Renal Data System database. Survival for the endpoints of all-cause death, cardiac death, myocardial infarction, and cardiac death or myocardial infarction was estimated by the life-table method and was compared by the log-rank test. The impact of independent predictors on survival was examined in a Cox regression model with comorbidity adjustment. Results The in-hospital mortality was 5.4% for 6887 PTCA patients and 12.5% for 7419 CAB patients. The two-year event-free survival (± SE) of PTCA patients was 52.9 ± 0.7% for all-cause death, 72.5 ± 0.7% for cardiac death, and 62.0 ± 0.7% for cardiac death or myocardial infarction. In CAB patients, the comparable survivals were 56.9 ± 0.6, 75.8 ± 0.6, and 71.3 ± 0.6%, respectively ( P Conclusions In this retrospective study, dialysis patients in the United States had better survival after CAB surgery compared with PTCA, but our study does not exclude the possibility of more unfavorable coronary anatomy in the PTCA patients at baseline. Our data support the need for prospective trials of newer percutaneous coronary revascularization procedures in dialysis patients.
Conditioned inhibition of the nictitating membrane response in rabbits following hypothalamic and mesencephalic lesions.

Rabbits were trained on a Pavlovian conditioned inhibition (CI) task using light as the reinforced conditioned stimulus (CS+) and the same light compounded with a tone as the nonreinforced CS-. The conditioned response was the nictitating membrane response. After attaining a criterion of CI performance, animals received radio-frequency lesions of the hypothalamus (n = 11) or midbrain (n = 14). For the hypothalamic lesion cases, primary damage extended from the optic chiasm to the pretectal region. For the mesencephalic lesion cases, primary damage ranged from the most rostral portions of the periaqueductal grey (PAG) caudally to the tegmental reticular formation at the level of the third nerve. Prior research suggested that the hypothalamic lesions would disrupt retention of CI by increasing responding to the CS-. Except where a lesion impinged upon the zona incerta, no CI disruption was observed. In accordance with previous studies (Berthier, N.E. and Moore, J.W., Physiol. Behav., 25 (1980) 667-673; Mis, F.W., J. Comp. Physiol. Psychol., 91 (1977) 975-988), post-lesioning CI disruption was observed in some of the mesencephalic lesion cases involving the posterior commissure, PAG and/or accessory oculomotor nuclei. However, CI performance recovered over the course of retraining.
A Heterogeneous Expression Pattern for Nanog in Embryonic Stem Cells

Nanog is a critical homeodomain factor responsible for maintaining embryonic stem (ES) cell self-renewal and pluripotency. Of interest, Nanog expression is not homogeneous in the conventional culture of murine ES cells. A Nanog-high population expresses markers for pluripotent ES cells, whereas a Nanog-low population expresses markers for primitive endoderm, such as Gata6. Since the inner cell mass of early blastocysts has recently been reported to be heterogeneous in terms of Nanog and Gata6 expression, ES cells appear to closely resemble the developing stage from which they originate. We further demonstrate that Nanog can directly repress Gata6 expression through its binding to the proximal promoter region of the Gata6 gene and that overexpression of Nanog reduces heterogeneity during ES cell maintenance. Interestingly, Nanog heterogeneity does not correlate with the heterogeneous expression of stage-specific embryonic antigen-1, suggesting that multiple but overlapping levels of heterogeneity may exist in ES cells. These findings provide insight into the factors that control ES cell self-renewal and the earliest lineage commitment to primitive endoderm while also suggesting methods to promote homogeneity during ES cell maintenance. Disclosure of potential conflicts of interest is found at the end of this article.
Superspreading: A possible mechanism

Abstract It is suggested that superspreading of droplets of dilute aqueous solutions of siloxane surfactants over a hydrophobic surface is driven by: (i) the spreading at their leading edges of the surfactant as bilayers, (ii) the suction of water in the hydrophilic atmosphere between the two layers and (iii) the displacement of the surfactant and water by a Marangoni effect intensified by the formation of bilayers. An explanation is provided for the observation that the rate of spreading passes through a maximum at an optimum degree of surface wettability (surface hydrophobicity).
Multi-walled Carbon Nanotubes/Poly(L-lactide) Nanocomposite Strain Sensor for Biomechanical Implants

Many biomedical applications require high sensitivity for measuring strain induced in biomechanical structures. Although current metallic foil strain gauges are capable of measuring strain deformations, their low sensitivity and relatively large size render them unsuitable for implantable and wearable application. In this paper, we present a novel nanocomposites strain sensor using poly(L- lactide) (PLLA) as a host polymer matrix and multi-walled carbon nanotubes (MWNTs) as filler. The PLLA matrix improves load transfer across the nanotubes by means of better interfacial bonding between polymer and carbon nanotubes filler, thus endowing the nanocomposites material with excellent piezoresistive property. Experimental results using a fabricated nanocomposites strain sensor is presented demonstrating its linear response and high gauge factor. Due to biocompatibility and biodegradability of PLLA, the proposed sensor is attractive for many biomedical and wearable applications.
Rai1 duplication causes physical and behavioral phenotypes in a mouse model of dup(17)(p11.2p11.2).

Genomic disorders are conditions that result from DNA rearrangements, such as deletions or duplications. The identification of the dosage-sensitive gene(s) within the rearranged genomic interval is important for the elucidation of genes responsible for complex neurobehavioral phenotypes. Smith-Magenis syndrome is associated with a 3.7-Mb deletion in 17p11.2, and its clinical presentation is caused by retinoic acid inducible 1 (RAI1) haploinsufficiency. The reciprocal microduplication syndrome, dup(17)(p11.2p11.2), manifests several neurobehavioral abnormalities, but the responsible dosage-sensitive gene(s) remain undefined. We previously generated a mouse model for dup(17)(p11.2p11.2), Dp(11)17/+, that recapitulated most of the phenotypes observed in human patients. We have now analyzed compound heterozygous mice carrying a duplication [Dp(11)17] in one chromosome 11 along with a null allele of Rai1 in the other chromosome 11 homologue [Dp(11)17/Rai1– mice] in order to study the relationship between Rai1 gene copy number and the Dp(11)17/+ phenotypes. Normal disomic Rai1 gene dosage was sufficient to rescue the complex physical and behavioral phenotypes observed in Dp(11)17/+ mice, despite altered trisomic copy number of the other 18 genes present in the rearranged genomic interval. These data provide a model for variation in copy number of single genes that could influence common traits such as obesity and behavior.
Fatty acid oxidation and some participating enzymes in animal organs.

Abstract 1. 1. The activity of an enzyme of the fatty acid oxidation cycle is compared to the activity of both short- and long-chain carnitine acyltransferase in organs of rat, pigeon and locust. 2. 2. In muscular tissue a constant relation between the activity of the tranferases and the capacity for fatty acid oxidation is established. 3. 3. In liver and kidney the activity of the long-chain transferase follows the activity of the fatty acid oxidation cycle; this, however, does not hold for short-chain transferase. 4. 4. As carnitine acyltransferases are important in fatty acid transport within the mitochondria, these results can be explained by accepting differences in the structure of the mitochondrial membranes between the different organs.
A Gated Electrostatic Ion Trap To Repetitiously Measure the Charge and m/z of Large Electrospray Ions

The design and operation of a new type of ion trap provides a way to measure mass, charge, and velocity of large individual electrospray ions (>1 MDa, >250 charges) repeatedly during the time the ion is trapped. The trap consists of an image charge detection tube mounted between two ion mirrors. The mirrors are sets of parallel electrodes drilled with holes aligned with the bore of the detector tube. The device relies on voltages applied to the electrodes to establish symmetrically opposing ion focusing mirrors for the purpose of cycling ions through the charge detection tube many times. This design does not use magnetic or radio frequency fields to trap ions. Gating one of the mirrors to 0 V while maintaining voltages appropriate for reflecting ions on the opposite mirror allows an ion to pass through the holes in the mirror and enter the detector tube. A low-noise charge-sensitive amplifier, connected to the tube, reproduces the image charge of individual ions as they pass through the detector tube. Whe...
Purple membrane vesicles: morphology and proton translocation.

Purple membrane vesicles prepared by different techniques differ widely in their morphology and ability to establish a proton gradient in the light. The procedures used to prepare active vesicles do not completely dissociate the purple membrane and thus preserve a preferential orientation of the protein, while most of the lipid is exchanged for added lipid. Responses to illumination are largely determined by the size of the vesicles and the degree to which bacteriorhodopsin is preferentially oriented. Any attempt to compare the interaction of different lipids with bacteriorhodopsin by measuring the pH response must take these factors into account.
An implementation of Eisner v. Macomber

Eisner v. Macomber , 252 U.S. 189 (1920), a corporate tax case, was the principal illustration of a theory of legal reasoning and legal argumentation proposed more than ten years ago. Although the theory was described in some detail, using the vocabulary of prototypes and deformations, it was never fully implemented. There were two main problems: (1) the knowledge represen- tation languages available at the time were not suf- ciently expressive, and (2) as a result, the central concept of a prototype was never suciently formal- ized. These problems have been remedied by subse- quent work, and the present paper describes an im- plementation (in PROLOG) of the original theory. A study of the implemented system provides a rational reconstruction of the arguments of Justice Pitney and Justice Brandeis in this seminal corporate tax case.
Semiempirical valence-bond resonance energies for alternant conjugated hydrocarbons containing four-membered rings

Resonance energies of alternant conjugated hydrocarbons containing six-membered and four-membered rings are discussed via the semiempirical valence bond (VB) theory. After generating the higher-order effective VB model according to cluster-expansion theory, the aromaticity or antiaromaticity of the above compounds is quantified in a correct manner. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2003
Immunology of tuberculosis and implications in vaccine development

Mycobacterium tuberculosis is a very successful pathogen that can survive and persist in the human host in the face of a robust immune response. This immune response is sufficient to prevent disease in the majority of infected persons, providing compelling evidence that immunity to tuberculosis is possible. However, it is more striking that the strong immune response is not generally effective at eliminating the organisms, during either initial infection or the persistent or latent phase of infection. Studies in animal models and in humans have demonstrated the wide range of immune components involved in the effective response against M. tuberculosis. These components include T cells (both CD4+ and CD8+), cytokines, including IFN-gamma, IL-12, TNF-alpha, and IL-6, and macrophages. The precise roles and functions of these cells and molecules (and others) are still being defined and may differ in acute and chronic infection. These immune responses are directed towards containing or eliminating the tubercle bacillus within the tissues of the host. The estimated eight million new cases of tuberculosis each year clearly demonstrate that these responses are not always effective. M. tuberculosis has obviously evolved a variety of mechanisms to evade destruction by the immune response. Studying both the host and the pathogen will elucidate potential vaccine candidates. In this review, the known functions of immune components in the response to M. tuberculosis and implications for vaccine development will be discussed.
Investigation of radiation damage effects in neutron irradiated CCD

Abstract A Charge Coupled Devices (CCD)-based vertex detector is a leading option for vertex detection at the future linear collider. A major issue for this application is the radiation hardness of such devices. Tests of radiation hardness of CCDs used in the SLD vertex detector, VXD3, have been reported earlier. The first measurements of 1998 involved a spare VXD3 CCD that was irradiated with neutrons from a radioactive source (Pu–Be), and from a nuclear reactor. In 2003, we had the opportunity to disassemble the VXD3 detector and study the nature of the radiation damage it incurred during 3 years of operation at SLC. In the preparation for this study, additional experiments with the spare VXD3 CCD were performed. These included measurements of trapping times in neutron irradiated CCDs. Results, reported here, will help us better understand the mechanism of radiation damage effects and develop techniques to minimize performance degradation due to radiation damage.
Stress mapping of undamaged, strained, and failed regions of bone using Raman spectroscopy.

Stress differences via spectral shifts that arise among failed, strained, and undamaged regions of bone can be determined using Raman spectroscopy and double-notch specimens. A double-notch specimen is a model in which the early stages of fracture can be examined. At four-point bending, fracture occurs at one of the notches. Tissue near each notch is representative of bone in a state either directly before or after bone failure. Raman images are acquired among three regions: control, strained root of unbroken notch, and failed root of fractured notch. The center of gravities CGs, a way to monitor wavenumber shifts, of the phosphate v1 band are calculated. A PO 4 v1 band shift most likely corresponds to a change in spacing between phosphate cations and anions. This spectral shift is converted into stress values using the dv/dP coefficient, determined by applying known pressures/stresses and measuring the change in position of the PO4 v1 band. In comparison to control regions, the residual stress in strained and failed regions is significantly higher p=0.0425 and p=0.0169, respectively. In strained regions, residual stress is con- centrated near the corners of the unbroken notch, whereas in failed regions the high stresses are confined near the edge of the fracture.
Synthetic Imogolite Paracrystals

Imogolite is a structurally microporous tubular clay comprising one-dimensional pore channels that are ~1 nm in diameter. In addition to its novel tubular morphology, a notable structural characteristic of imogolite is its occurrence in paracrystalline tube bundles in which the individual tubes are close-packed with their axes in parallel alignment. We have developed a technique that aligns and tightly packs the tube bundles over macroscopic dimensions, in a manner analogous to the alignment and packing of the individual imogolite tubes within the bundles. This extends the range of imogolite paracrystallinity, effectively eliminating mesoporosity and non-tubular phases.
Thermoelastic limit cycling of zippered cross section spacecraft booms

The phenomenon of thermal flutter of open cross section storable tubular extendible member (STEM) spacecraft booms was first observed in OGO IV and subsequently on a number of other satellites. Theoretical work ultimately ascribed the anomalous, undamped oscillations to the low torsional rigidity of the open section booms. This was confirmed when 'zippered' cross section booms, with substantially higher torsional rigidity, were later flown without exhibiting thermal flutter. However, zippered STEM booms generally have sizeable torsional backlash zones. It is shown here that small amplitude thermoelastic limit cycling within this backlash zone is theoretically possible and is the likely explanation for undamped oscillations recorded on Voyager 1 and 2 in the early stages of the Voyager mission.
Effect of heart-rate control training on heart-rate discrimination.

4 subjects were exposed to discrimination-testing procedures before and after biofeedback training to increase and decrease their heart rates. Results indicated significant increases and decreases in heart rate, as well as a significant improvement in accuracy of discrimination. The results suggest improvements in discrimination may occur as a function of feedback training.
ENCEPHALOPATHY FOLLOWING INFLUENZA IMMUNIZATION.

A case of encephalopathy apparently secondary to the administration of influenza vaccine is reported. Although neurologic sequelae of prophylactic inoculations are not rare, encephalopathy following influenza immunization has been infrequently reported.
Supervisory telerobotics testbed for unstructured environments

A telerobotics testbed for performing tasks such as assembly and repair of spacecraft in unstructured environments is described. This fully operational multiarm system can operate in teleoperated or supervisory control modes, as well as mixed shared-control modes, thus enabling operations in totally to partially unstructured environments. Various sources of uncertainty are identified and approaches to minimize their effects are presented. In the teleoperated mode, the system uses two force-reflecting hand controllers to operate two manipulator arms. A third arm is utilized to position four cameras to view the scene. In the supervisory mode, the system can be operated from three different levels: task, process, and servo levels, providing different levels of autonomy and performance. Various tools are provided so that an operator can perform tasks even when objects are partially occluded or their positions are not known a priori.
The computer program STRUCTURE does not reliably identify the main genetic clusters within species: simulations and implications for human population structure.

One of the primary goals of population genetics is to succinctly describe genetic relationships among populations, and the computer program STRUCTURE is one of the most frequently used tools for doing so. The mathematical model used by STRUCTURE was designed to sort individuals into Hardy–Weinberg populations, but the program is also frequently used to group individuals from a large number of populations into a small number of clusters that are supposed to represent the main genetic divisions within species. In this study, I used computer simulations to examine how well STRUCTURE accomplishes this latter task. Simulations of populations that had a simple hierarchical history of fragmentation showed that when there were relatively long divergence times within evolutionary lineages, the clusters created by STRUCTURE were frequently not consistent with the evolutionary history of the populations. These difficulties can be attributed to forcing STRUCTURE to place individuals into too few clusters. Simulations also showed that the clusters produced by STRUCTURE can be strongly influenced by variation in sample size. In some circumstances, STRUCTURE simply put all of the individuals from the largest sample in the same cluster. A reanalysis of human population structure suggests that the problems I identified with STRUCTURE in simulations may have obscured relationships among human populations—particularly genetic similarity between Europeans and some African populations.
Formulation of a Ritz-Galerkin Type Procedure for the Approximate Solution of the Neutron Transport Equation*

Abstract The one-group neutron transport equation is commonly given as an integrodifferential equation for the neutron density ψ(x, ω) over a domain G × S in the five-dimensional phase space E 3 × S(¦ ω ¦ = 1) . In this paper we show how, by decomposing the domain of the transport operator into a complementary pair of manifolds by means of a projection operator, any transport problem can be formulated, on either manifold, in terms of a symmetric positive definite operator. We use Friedrichs' method to extend the operator to a selfadjoint operator and look for a generalized solution by minimizing a certain functional over the appropriate Hilbert space. A Ritz-Galerkin type approximation procedure is formulated, and an estimate for the difference between the exact and approximate solution is given. The procedure is illustrated for a special choice of finite dimensional subspace.
HEME OXYGENASE-MEDIATED RESISTANCE TO OXYGEN TOXICITY IN HAMSTER FIBROBLASTS

The role of heme oxygenase (HO)-1 was evaluated in the oxygen-resistant hamster fibroblast cell line, O2R95, which moderately overexpress HO when compared with the parental cell line, HA-1. To suppress HO-1 expression, O2R95 were transfected with HO-1 antisense oligonucleotide or treated with tin-mesoporphyrin (SnMP). To increase HO-1 expression, cells were transfected with HO-1 cDNA in a pRC/cytomegalovirus (CMV) vector. All cells were challenged with a 48-h exposure to 95% O2 (hyperoxia). When HO activity was suppressed, O2R95 cells had significantly decreased cell viability, increased susceptibility to lipid peroxidation, and increased protein oxidation in hyperoxia. In contrast, further overexpression of HO-1 did not improve resistance to oxygen toxicity. Antisense-transfected cells and SnMP-treated cells with lowered HO activity showed increased levels of cellular heme compared with controls. In the HO-1 cDNA-transfected O2R95 cells, cellular heme was lowered compared with controls; however, cellular redox active iron levels were increased. We conclude that HO mediates cytoprotection to oxygen toxicity within a narrow range of expression. We speculate that this protective effect may be mediated in part through increased metabolism of the pro-oxidant heme but that higher levels of HO activity obviate protection by increased redox active iron release.
The wear behaviour of electro-codeposited Ni–SiC composites

Abstract In this study, attempt has been made to investigate the wear resistance of Ni–SiC composites manufactured by electro-codeposition process, which is significantly correlated to the vol.% SiC in the matrix. In addition, the vol.% of SiC is closely related to the concentration of submicron SiC and the surfactant in the bath. It is found that the surfactant CTAB can not only disperse the SiC particles well in the electrolyte therefore leading to better homogeneously distributed SiC particles in the matrix but also enhances the SiC vol.% embedded in codeposition layer. It is confirmed that the wear resistance of codeposited layer increases with increasing submicron-size vol.% SiC.
Experimental analysis of Msx-1 and Msx-2 gene expression during chick mandibular morphogenesis

Homeobox-containing genes are thought to be involved in regulating pattern formation in a variety of tissues during embryogenesis. We have examined the expression of the homeobox-related genes Msx-1 and Msx-2 during the development of the chick mandibular arch. Northern blot hybridization indicates that transcripts for both Msx-1 (1.6 Kb) and Msx-2 (3 Kb) are present in the mandibular arch as early as stage 18. The levels of both transcripts in the whole mandible decrease as cartilage is formed in vivo and in vitro. Using in situ hybridization, transcripts of Msx-1 were localized in high amounts to the mesenchyme of the mesial tips of the arches. Msx-2 transcripts were localized in high amounts to medial regions of the arches. Little or no hybridization of either probe was detected in the chondrogenic and myogenic regions of the arches. Transcripts of both genes were also excluded from calcified bone and cartilage. Our results further demonstrate that the mesial tip mesenchyme expressing Msx-1 includes areas of highly proliferative cells and has in vitro chondrogenic potential. The region of mesenchymal cells expressing the Msx-2 gene overlap with areas of developmentally programmed cell death which also contain very few proliferative cells and lack chondrogenic potential in vitro. These results are consistent with the possibility that Msx-1 may be involved in the outgrowth of the mandibular arch and Msx-2 may be involved in both developmentally programmed cell death and delineating the non-chondrogenic region of the medial part of the mandibular arch.
Chromosomal evolution of the Hawaiian Telmatogeton (Chironomidae, Diptera)

It is only in the Hawaiian Islands that species of the otherwise marine genus Telmatogeton have evolved into freshwater. An analysis of polytene chromosomes and karyotypes of two marine species and five freshwater species revealed that paracentric inversions and centric fusions were important in chromosomal evolution. The sequence of polytene chromosome bands common to most species, established as the Telmatogeton standard sequence, is found in a population of T. torrenticola from West Maui. Most species and other populations of T. torrenticola may be derived from the standard sequence by paracentric inversions. Similarities with the standard band sequence places T. japonicus (n=7) rather than T. pacificus (n=4) in the proposed phylogeny as the species closest to the marine ancestor of the freshwater species. One of three species (T. fluviatilis from Oahu, T. torrenticola from West Maui, or an undescribed species from East Maui), each with seven pairs of chromosomes is considered to be closest to the original freshwater species. T. torrenticola is a complex species in which there is an accumulation of fixed inversions and centric fusions in stepwise fashion in populations from west to east (West Maui n=7; East Maui n=6; Kohala Mountains n=5 and Mauna Kea n=4 both from the island of Hawaii). The population of T. torrenticola from Molokai has a reduced chromosome number (n=4) and fixed inversions. T. abnormis and T. hirtus, the only species which exhibit differentiated sex chromosomes, may be derived from the standard sequency by paracentric inversions. T. abnormis (n=4) has a simple XY system and T. hirtus (n=3/4) has a complex XY1Y2 system. Unique sequences of bands, differences in staining intensity of puffs and bands, and an inversion form the basis for the differentiation of the various Y-chromosomes in these species.