cssi/SciSciGPT-SciSciNet huggingface dataset:
Application of lattice Boltzmann method, finite element method, and cellular automata and their coupling to wave propagation problems

Three different computational techniques were applied to wave propagation problems. Those techniques were the lattice Boltzmann method, finite element method, and cellular automata. The formulation of each technique was presented, and the coupling procedures of those techniques were also presented. For example, a part of the problem domain was solved using one analysis technique while the other part was analyzed by another technique. Such coupled techniques may overcome the difficulties that a single technique has, and they may also provide their own advantages of two different methods in a single analysis depending on application problems. For example, one technique is computationally more efficient while another is useful to model a complex or irregular shape of domain. Combining the two techniques will be beneficial to solve a complex domain shape with computational efficiency. The accuracy of the different techniques including the coupled methods was numerically demonstrated by comparing their solutions to other solutions available for wave propagation problems in 1-D and 2-D.
Mode of Action for Linear Peptide Inhibitors of HIV-1 gp120 Interactions

The linear peptide 12p1 (RINNIPWSEAMM) was previously isolated from a phage display library and was found to inhibit interaction of HIV-1 gp120 with both CD4 and a CCR5 surrogate, mAb 17b [Ferrer, M., and Harrison, S. (1999) J. Virol. 73, 5795-5802]. In this work, we investigated the mechanism that leads to this dual inhibition of gp120 binding. We found that there is a direct interaction of 12p1 with gp120, which occurs with a binding stoichiometry of 1:1. The peptide inhibits binding of monomeric YU2 gp120 to both sCD4 and 17b at IC(50) values of 1.1 and 1.6 microM, respectively. The 12p1 peptide also inhibited the binding of these ligands to trimeric envelope glycoproteins, blocked the binding of gp120 to the native coreceptor CCR5, and specifically inhibited HIV-1 infection of target cells in vitro. Analyses of sCD4 saturation of monomeric gp120 in the presence or absence of a fixed concentration of peptide suggest that 12p1 suppression of CD4 binding to gp120 is due to allosteric inhibitory effects rather than competitive inhibition of CD4 binding. Using a panel of gp120 mutants that exhibit weakened inhibition by 12p1, the putative binding site of the peptide was mapped to a region immediately adjacent to, but distinguishable from, the CD4 binding footprint. In the case of the peptide, the effects of single-12p1 residue substitutions and various peptide truncations indicate that the side chain of Trp7 and other structural elements of 12p1 are critical for gp120 binding or efficient inhibition of binding of a ligand to gp120. Finally, 12p1 was unable to inhibit binding of sCD4 to a gp120 mutant that is believed to resemble the CD4-induced conformation of gp120. These results suggest that 12p1 preferentially binds gp120 prior to engagement of CD4; binding of the peptide to gp120 limits the interaction with ligands (CD4 and CCR5) that are generally crucial for viral entry. More importantly, these results indicate that 12p1 binds to a unique site that may prove to be a prototypic target for novel CD4-gp120 inhibitors.
Duration and Timing of Sleep are Associated with Repetitive Negative Thinking

Higher levels of repetitive negative thinking (RNT; a perseverative and abstract focus on negative aspects of one’s experience) are associated with reduced sleep duration. This information is already informing theory and clinical practice. However, we are not aware of any studies examining the relation between RNT and the timing of sleep. We examined both disorder specific measures of RNT and a transdiagnostic measure of the RNT process in relation to sleep duration and timing in a sample of 100 unselected undergraduates. Replicating prior findings, shorter sleep duration was cross-sectionally associated with more rumination and delayed sleep timing was associated with more obsessive–compulsive symptoms. Further, extending this prior work, the transdiagnostic measure of RNT was associated with shorter sleep duration and delayed sleep timing. Individuals who endorsed a preference for later sleep and activity times also reported more RNT. These findings suggest that RNT may be uniquely related to both sleep duration and timing.
Fibrin Sealant Tissue Adhesive−Review and Update

The field of surgical tissue adhesives is rapidly developing, with multiple products now available. Fibrin sealant, the first widely available tissue adhesive, continues to be used in traditional as well as in new and creative ways. The product is now fully mature as a hemostatic agent in cardiac, liver, and spleen surgery. It is also useful as a sealant in a variety of clinical applications, including procedures such as colonic anastomosis, as well as in seroma prevention following soft tissue dissection. Newer uses such as reduced suture vascular and intestinal anastomosis, fistula closure, surgery in patients with hemophilia, and laparoscopic/endoscopic procedures are being studied in both laboratory and clinical settings. The most recent additions to the capabilities of fibrin sealant include the use of this tissue adhesive as a slow-release drug delivery system and as a substrate for cellular growth and tissue engineering. This article will review the basis of fibrin sealant effectiveness and will also cover the recent developments in the rapidly evolving employment of this material.
Genotoxic effects of complex marine sediment extracts on V79 chinese hamster lung fibroblasts

A mammalian in vitro system was used to evaluate the genotoxic potential of two complex environmental samples. Sister chromatid exchanges (SCEs) were measured in Chinese hamster V79 lung fibroblast cells, following exposure to whole extracts of sediments collected from a highly contaminated harbor — Black Rock Harbor, Connecticut (BRH) — and from a reference site — central Long Island Sound (CLIS). Characterization of BRH sediment by analysis of prepared chemical extracts revealed high concentrations of polyaromatic hydrocarbons, anthraquinones, carbazoles, and several inorganic substances that are genotoxic and capable of inducing SCEs. The CLIS sediment, although cleaner than BRH sediment, does contain low levels of similar contaminants. For instance, BRH sediment contains 3.16 μg/g of the polynuclear aromatic hydrocarbon benzo[a]pyrene (BP), whereas CLIS sediment contains only 0.807 μg/g BP. Sediments were extracted with organic solvents and redissolved in dimethyl sulfoxide (DMSO) for culture exposure. Following exposure, extract-treated cells were evaluated for increased frequencies of SCEs. All assays were performed with and without exogenous S9 activation. Positive responses were observed only in the presence of exogenous S9 metabolism. Results indicated a concentration-dependent increase in SCEs in cells exposed to whole BRH sediment extracts and a smaller but significant increase in SCEs in cells exposed to whole CLIS sediment extracts. Four times as much CLIS material (0.13 g extracted sediment [dry wt.]/ml of exposure media) was needed to induce a significant doubling in SCEs, compared to BRH material, in which only 0.03 g extracted sediment (dry wt.)/ml of exposure media was needed. These findings imply that this short-term in vitro bioassay can be used to evaluate the genotoxic potential of complex environmental samples such as contaminated marine sediments.
Oesophageal varix bleed

23 Caugant DA. Population genetics and molecular epidemiology of Neisseria meningitidis. APMIS 1998; 106: 505–25. 24 Spiegel A, Greindl I, Bordonado JL, et al. Fiabilite du diagnostic de meningite cerebospinale en periode epidemique. A propos de l’epidemie de Tchad en 1988. Bull Soc Pathol Exot 1990; 83: 642–48. 25 Lewis R, Nathan N, Communier A, et al. Mieux detecter les epidemies de meningite a meningocoque en Afrique: une nouvelle recommendation. Cahiers Sante (in press). 26 Wenger J, Tikhomirov E, Barakamfitiye D, Bele O, Heymann DL. Meningococcal vaccine in sub-Saharan Africa. Lancet 1997; 350: 1709. 27 Kaninda AV, Varaine F, Henkens M, Paquet C. Meningococcal vaccine in sub-Saharan Africa. Lancet 1997; 350: 1708. 28 Reingold AL, Hightower AW, Bolan GA, et al. Age-specific differences in duration of clinical protection after vaccination with meningococcal polysaccharide A vaccine. Lancet 1985; 2: 114–18. 29 MacLennan J, Obaro S, Deeks J, et al. Immune response to revaccination with meningococcal A and C polysaccharides in Gambian children following repeated immunisation during early childhood. Vaccine 1999; 17: 3086–93. 30 Hassan-King MKA, Wall RA, Greenwood BM. Meningococcal carriage, meningococcal disease and vaccination. J Infect 1988; 16: 55–59. 31 Blakebrough IS, Greenwood BM, Whittle HC, Bradley AK. Failure of meningococcal vaccination to stop the transmission of meningococci in Nigerian schoolboys. Ann Trop Med Parasitol 1983; 77: 175–78. 32 Campagne G, Garba A, Fabre P, et al. Safety and immunogenicity of three doses of a Neisseria meningitidis A+C diphtheria conjugate vaccine in infants from Niger. Pediatr Infect Dis J 2000; 19: 144–50. ARTICLES
Angioscopic evaluation of periprocedural and postprocedural abrupt closure after percutaneous coronary angioplasty

Abrupt closure remains a significant complication of PTCA. On the basis of the presumption of underlying cause (thrombus, dissection, spasm), various empiric medical and mechanical interventions have been used to prevent and/or treat this event. Despite these measures, however, abrupt closure remains a highly unpredictable occurrence with a substantial incidence of myocardial infarction and angioplasty-related morbidity and mortality. Direct visualization of the site of abrupt closure may allow determination of responsible mechanisms and appropriate treatment strategies. Intracoronary visualization using a new angioscope was carried out in two cases of abrupt closure after percutaneous coronary angioplasty. The angioscope features a movable fiberoptic bundle that provides continuous and uninterrupted imaging of the coronary artery segment incorporating the site of abrupt closure. In one patient with intraprocedural closure angioscopy revealed obstruction of the lumen with extruded plaque material. In a second patient with postprocedural closure, however, imaging at the site of coronary artery occlusion revealed a mass consistent with a large platelet thrombus. Intracoronary evaluation with angioscopy may yield important characteristics that identify lesions at risk for abrupt closure. Further elucidation of the mechanisms underlying abrupt closure may allow more appropriate selection of therapeutic interventions.
Elastic and inelastic scattering of 15 MeV polarized deuterons from Ti, Cr, Fe and Ni isotopes

Abstract The elastic and inelastic scattering of 15 MeV polarized deuterons from 48 Ti, 50 Ti, 52 Cr, 54 Fe, 56 Fe, 58 Ni, 60 Ni, 62 Ni and 64 Ni has been investigated. Angular distributions of the cross section and vector analyzing power iT 11 have been measured for most of these nuclei. The tensor analyzing powers T 20 and T 22 have been studied for 54 Fe, 56 Fe, and 62 Ni in both elastic and inelastic scattering; T 21 has been measured for 54 Fe and 56 Fe. Cross sections and vector analyzing powers are reasonably well explained by the optical model for elastic scattering and by the DWBA with a macroscopic form factor for the inelastic scattering. Anomalous behavior of the N = 28 nuclei found in the inelastic scattering of polarized protons is not present for deuterons. The effect of a distorted spin-orbit term is negligible. Tensor analyzing powers for both elastic and inelastic scattering are poorly fitted with standard procedures; the introduction of a T R tensor potential does not improve the predictions.
Action of Ammonium Sulfate Solution on Dry Milk Powders

Abstract Milk powders dispersed in concentrated solution of ammonium sulfate maintain their structural configurations in spite of loss of lactose and calcium. In 95% saturated ammonium sulfate solutions, protein is not removed but lactose and calcium are rapidly and completely removed. In 50% saturated ammonium sulfate, some whey proteins were also removed without affecting the particles physical appearance. Some fragmentation occurred in all foam spray-dried powders probably from coalescence of interior gas bubbles in these less dense particles. Agglomerates of instantized skimmilk powder were broken down to their fundamental particles by the ammonium sulfate solutions, appearing thereafter much the same as noninstantized skimmilk particles. These phenomena indicate that, in the terminal stages of drying, proteins may interact to form a continuous phase in spray-dried milk and that lactose may be the bridging material in the formation of powder particle aggregates during instantizing.
Identification of communication networks in Spo0F: a model for phosphorylation-induced conformational change and implications for activation of multiple domain bacterial response regulators

Abstract Fundamental to understanding the mechanism by which phosphorylation activates bacterial signal transduction response regulator proteins is the identification of regions and residues that are responsible for the phosphorylation-induced conformational change. Here we review results from structural and protein dynamics investigations, and combine them with mutagenesis studies on the response regulator protein Spo0F to suggest a model in which a network of buried and surface residues link surface regions required for protein:protein interactions to the site of phosphorylation. The network described for Spo0F may provide pathways through which information is transmitted from the site of phosphorylation, propagating a conformational change many angstroms away. The general applicability of the communication network model for all bacterial response regulator proteins is discussed.
Predicting the need for laparotomy in pediatric trauma patients on the basis of the ultrasound score.

Background: It is possible to quantify the amount of hemoperitoneum seen on focused assessment with sonography for trauma (FAST) using a simple scoring system that had previously been shown to correlate with the need for subsequent laparotomy in adults. A score of 3 or greater was shown to be highly accurate in predicting the need for laparotomy. We hypothesized that this scoring system might also predict the need for laparotomy in pediatric trauma patients. Methods: We retrospectively reviewed all records for patients 15 years and younger who underwent FAST after blunt trauma. A positive ultrasound examination was defined as one containing free intraperitoneal fluid with or without solid organ injury. The ultrasound score (USS) was defined as the depth of the deepest pocket of fluid collection measured in centimeters plus the number of additional spaces where fluid was seen. Results: Thirty-eight (19.6%) of 193 patients who had FAST performed had positive ultrasound examinations. Thirty-seven patients with complete records were analyzed. There were no differences between patients with a USS ≤3.0 and those with a USS > 3.0 in terms of admission pulse, Glasgow Coma Scale score, Injury Severity Score, or the proportion of patients who were initially hypotensive. One of 22 patients with a USS ≤3.0 required therapeutic laparotomy versus 8 of 15 patients with a USS > 3.0 (p = 0.002). For a USS > 3.0, sensitivity, specificity, and accuracy in predicting therapeutic laparotomy were 89%, 75%, and 78%, respectively. CoflclvsloAl Ultrasound quantification of hemoperitoneum by a simple scoring system may serve as a useful adjunct to traditional clinical parameters in predicting the need for subsequent laparotomy in pediatric patients. Prospective validation with a larger study is required.
DESCRIPTION, PERFORMANCE, AND CALIBRATION OF A CHARGE-COUPLED-DEVICE CAMERA

A description is given of the SAO CCD camera using the 100 x 100 Fairchild chip operated in a direct imaging mode, together with extensive data on its performance in the laboratory and at the telescope. Short descriptions of the cryogenic, electronic, computer control, and optical systems are presented. Laboratory measurements of the correction for the nonuniformity in sensitivity, linearity, system noise, quantum efficiency, and dark current are discussed. Calibrations of the positions and magnitudes of standard stars in clusters and the surface brightness of a standard galaxy are analyzed. These measurements illustrate the effectiveness of the camera as a photometric detector and also calibrate the parameters of the system.
2×CO2 and Solar Variability Influences on the Troposphere Through Wave-Mean Flow Interactions

A variety of climate forcings are now thought to be able to influence planetary wave dynamics in the troposphere by affecting the propagation of planetary waves out of the troposphere. However, this propagation pattern is sensitive to the details of the corresponding zonal wind changes. Here we discuss two forcing mechanisms that alter zonal winds and subsequent tropospheric responses: changes in atmospheric CO 2 concentrations, and solar forcing in conjunction with the QBO. Increased atmospheric CO 2 concentrations can be shown to influence planetary wave refraction so as to produce an intensified residual circulation in the subtropical lower stratosphere (which increases transport of tropospheric species into the stratosphere). In our GCM experiments, the low latitude response appears qualitatively robust over a wide range of tropical warming magnitudes, although the quantitative circulation change depends upon the degree of tropical warming as influenced by convection and cloud cover changes; it varies by a factor of three with a factor of three change in tropical warming. At higher latitudes, this equatorward planetary wave refraction has been associated with an increase in the high phase of the Arctic Oscillation. In the model experiments, the extratropical response depends upon the magnitude of both low and high latitude warming in the troposphere; with SST and sea ice changes that result in a weaker Hadley Cell and greater high latitude warming, the Arctic Oscillation phase change may be negative. The QBO alters the latitudinal gradient of the zonal wind in the stratosphere, and solar heating, in association with ozone response, alters the vertical gradient of the zonal wind. Both gradients affect the refractive properties of planetary waves uniquely for each individual combination of tropical east/west winds and solar maximum/minimum activity. In the model, when we consider solar maximum compared to solar minimum conditions, the east (west) phase of the QBO results in a relative high (low) phase of the Arctic Oscillation with corresponding temperature changes. Observed and modeled surface air temperature variations calculated between the solar cycle extremes in the different QBO phases are similar in magnitude to those derived from regression of monthly data on the AO, both being on the order of observed interannual variations.
Output sector munificence and supplier control in industrial channels of distribution: a contingency approach

Abstract Despite the previous finding that a scarce output sector condition increases the extent of supplier control over distributor operations, the exact nature of that effect remains vague. Relying on recent recognition that the governance of exchange relationships is driven by the interaction between environmental uncertainty (including munificence of the output sector) and interfirm dyadic conditions rather than by environmental uncertainty per se, the author maintains that the effect of output sector munificence on supplier control is contingent on two moderators: interdependence between channel members as a proxy of the interfirm structural condition and distributor satisfaction as a proxy of the interfirm attitudinal condition. The results of a national survey of industrial distributors support distinctive moderating effects of bilateral interdependence and distributor satisfaction.
The Hexameric Helicase DnaB Adopts a Nonplanar Conformation during Translocation

DNA polymerases can only synthesize nascent DNA from single-stranded DNA (ssDNA) templates. In bacteria, the unwinding of parental duplex DNA is carried out by the replicative DNA helicase (DnaB) that couples NTP hydrolysis to 5' to 3' translocation. The crystal structure of the DnaB hexamer in complex with GDP-AlF(4) and ssDNA reported here reveals that DnaB adopts a closed spiral staircase quaternary structure around an A-form ssDNA with each C-terminal domain coordinating two nucleotides of ssDNA. The structure not only provides structural insights into the translocation mechanism of superfamily IV helicases but also suggests that members of this superfamily employ a translocation mechanism that is distinct from other helicase superfamilies. We propose a hand-over-hand mechanism in which sequential hydrolysis of NTP causes a sequential 5' to 3' movement of the subunits along the helical axis of the staircase, resulting in the unwinding of two nucleotides per subunit.
Renovascular reconstruction: Factors affecting long-term prognosis in 919 patients followed up to 31 years

Abstract During the 31-year period from May 3, 1955, to May 12, 1986, renovascular reconstructions were performed on 919 patients. The mean age of the 529 men was 54 ± 0.58 (SE) years and, of the 390 women, 48 ± 0.7 years. Mean preoperative diastolic blood pressure was 110 ± 0.6 mm Hg. The most common causes of renal artery stenosis were atherosclerosis in 647 patients, fibromuscular disease in 161 patients, and renal artery aneurysm in 51 patients. In the remaining 60 patients, other causes were present, including kinks and fibrous bands. The most common surgical procedures were Dacron bypass graft (780 arteries) and endarterectomy with or without a patch graft (329 arteries). Four hundred sixty-nine patients had associated operations, the most common of which were abdominal aortic aneurysmectomy in 231 and aortoiliofemoral reconstruction in 141 patients. The perioperative mortality rate was 5.5% (51 of 919 overall); for renal procedures alone, it was 1.7% (8 of 450) and for combined surgical procedures, 9.2% (43 of 469). The overall graft patency rate at a follow-up of 18.8 ± 1.9 months was 88.6% (381 of 430) and at a second follow-up of 50 ± 4.3 months, 86.7% (111 of 128). Analysis of long-term blood pressure response and factors affecting late survival indicated that patients with preoperative diastolic pressures of >100 mm Hg and renal artery stenosis of >70% had the best blood pressure responses and that male sex, increasing age, bilateral renal stenosis, and associated vascular operations lowered the survival rate whereas fibromuscular disease enhanced the duration of survival. Thus, renal artery reconstruction resulted in sustained good long-term relief of hypertension and preservation of renal function in most patients. Some subgroups of younger patients had better survival rates, but this was not true of the subgroups of the elderly.
Effects of Conditioned Medium from Different Cultured Cell Types on Aromatase Expression in Adipose Stromal Cells

OBJECTIVE To determine whether serum-free (SF) conditioned media (CM) from several human breast cancer cell lines and primary stromal cell cultures contain factor(s) that mimic the marked stimulatory effects of serum on aromatase activity and aromatase P450 (P450arom) gene expression in adipose stromal cells in culture (ASC) in the presence of dexamethasone (DEX). METHODS Adipose stromal cells, harvested from fresh adipose specimens, were grown to confluence, switched to SF media, and then incubated in the presence or absence of DEX with CM from T47-D breast cancer cells, pre-treated with or without 17 beta-estradiol (E2), and with CM from stromal cell cultures. Aromatase activity of the ASC was determined by the [3H] water release assay. Total RNA was isolated, and reverse transcription-polymerase chain reaction was performed to determine the expression of various 5'-termini. RESULTS T47-D CM stimulated aromatase activity in a concentration-dependent manner, similar to that of serum, in ASC incubated with DEX. Estrogen potentiated this in a dose-dependent fashion. The ASC CM and endometrial stromal cell CM also markedly induced aromatase activity in ASC. Heat inactivation destroyed the stimulating ability of CM. The majority of P450arom 5'-termini expressed by ASC incubated with CM plus DEX contained the promoter I.4-specific sequence. CONCLUSIONS Conditioned media from several breast cancer cell lines and primary stromal cell cultures can mimic the effects of serum in the presence of DEX to stimulate aromatase activity in ASC. These results suggest that undefined, heat-labile and proteinaceous factors are present in CM that stimulate P450arom expression in a fashion similar to that of serum.
Evolution of Wolbachia pipientis transmission dynamics in insects

Wolbachia pipientis is an intracellular bacterial parasite of arthropods that enhances its transmission by manipulating host reproduction, most commonly by inducing cytoplasmic incompatibility. The discovery of isolates with modified cytoplasmic incompatibility phenotypes and others with novel virulence properties is an indication of the potential breadth of evolutionary strategies employed by Wolbachia.
Communicating Hydrocephalus as a Complication of Isolated CNS Angiitis—A Case Report

A sixty-six-year-old man presented with headache, left hemiparesis, right crural monoparesis, and urinary and fecal incontinence. A picture consistent with cerebral angiitis was seen angiographically. After systemic angiitis and CNS infection were excluded, the diagnosis of isolated angiitis of the central nervous system was made. The patient responded well to corticosteroid therapy. However, a few months after initial presentation, he developed signs and symptoms suggestive of hydrocephalus. Serial CT scans of the head and radioisotope cisternography confirmed this diagnosis. The communicating hydrocephalus that developed was considered a complication of the CNS angiitis. A review of the literature on angiitis of the CNS is presented and the mechanism of the development of hydrocephalus is discussed.
Word-boundary-related duration patterns in English

Abstract Segments and syllables with identical distinctive feature specifications in the lexicon can be produced with strikingly different durations in different contexts, depending for example on the location of a lexical word boundary. In a study of 11 triads like tune acquire, tuna choir and tune a choir, durational differences between, e.g.,tune acquire and tuna choir occurred on either side of the word boundary in a variety of prominence contexts, broadly confirming earlier findings in the literature for a more limited set of stimuli. In general, duration measurements fortune ♯a♯choir tokens were found to be intermediate between those oftune ♯acquire and tuna♯choir, suggesting that boundaries at function words are weaker than boundaries between two content words. In addition, an investigation of the distribution of durational differences across and within syllables was conducted to evaluate five duration adjustment mechanisms proposed in the literature. Support was found for word-initial lengthening, polysyllabic shortening, accentual lengthening, and syllable ratio equalization, but not for word-final lengthening.
The Invasive New Zealand Mud Snail (Potamopyrgus antipodarum) in Lake Erie

The New Zealand mud snail (Potamopyrgus antipodarum) is an invasive species in Europe, Japan, Australia, and North America. In the western United States it is a species of special concern where population densities in some rivers and streams are very large (∼300,000 per m2) and considerable ecological effects of its presence have been reported. Much less about the effects of this species is known in the Great Lakes, where the snail was found in Lake Ontario and the St. Lawrence River in 1991. Here we report the occurrence of the snail in Lake Erie. Two P. antipodarum were collected in 18 m deep water (sampling range 5–18 m) in Lake Erie off shore of Presque Isle State Park near Erie, Pennsylvania in the summer of 2005 and others were collected off of Sturgeon Point in Lake Erie (sampling range 5–20 m) south of Buffalo, NY and in the central basin of Lake Erie (18 m) in 2006. This finding demonstrates that this species continues to expand its range in the Great Lakes. The range expansion increases the likelihood that it may become established in rivers and streams emptying into the Great Lakes where higher densities and greater ecological damage may result.
Evaluation of aflatoxin B1 mutagenesis: addition of glutathione and glutathione-S-transferase to the Salmonella mutagenicity assay.

The effects of glutathione (GSH) and the combination of GSH and glutathione-S-transferase (GST) on aflatoxin B/sub 1/ (AFB/sub 1/) mutagenesis in the Salmonella mutagenicity assay using Salmonella typhimurium strains TA98 and TA100 were tested. Ten concentrations of AFB/sub 1/ (0-1.0 ..mu..g/plate) were added to a liver microsomal homogenate (S9 mix) or to S9 mix containing GSH or S9 mix containing the combination of GSH + GST. One third of the samples were plated directly. Two-thirds were incubated for 30 min at 37/sup 0/C prior to plating, and of those, half included bacteria. The results show that the addition of GSH and GSH + GST affected AFB/sub 1/ mutagenesis by forming the AFB/sub 1/-GSH conjugate and decreasing the availability of AFB/sub 1/-8,9-epoxide. The effect of GST on GSH activity varied with the strain because of the different amounts of S9 mix used. The formation of the AFB/sub 1/-GSH conjugate was verified by using reverse-phase high-performance liquid chromatography for quantitation of AFB/sub 1/ and detection of AFB/sub 1/-GSH.
On the Absolute Magnitudes of the O Stars

The conclusion published in 1992 by Garmany & Stencel from a study of northern OB associations, that the absolute magnitudes of the O stars show "a large scatter ... intrinsic to the classification system," is critically examined. It is found that the differences between their derived absolute magnitudes of O stars and this author's 1973 calibration exhibit large systematic effects in several associations, ranging from -0.74 to +1.02 mag with substantially smaller dispersions. Of course, when these results are combined, the scatter equals the full range of the systematic effects. To investigate the possibility of distance errors, the Garmany & Stencel B0–B2.5 stars in the same associations are subjected to the same analysis. The results for the B stars show no significant systematic differences, eliminating errors in the association distances derived by Garmany & Stencel from the B stars as the source of the differences found for the O stars. It is noteworthy that the dispersions in the absolute magnitudes of the B stars within a given association are similar to or larger than those of the O stars. An examination of the distribution on the sky of the stars shows that the O and B stars in the discrepant associations are generally not colocated; such was already known to be the case for the important Perseus OB1 association. It is suggested that despite their efforts to improve them, significant problems remain with the association memberships adopted by Garmany & Stencel; the relatively small dispersions of the O star absolute magnitudes even in the discrepant cases indicate that they belong to different, usually more distant associations near the lines of sight to the B associations with which they have been mistakenly connected. Several individual cases of unrecognized multiple systems and classification errors are also found in the Garmany & Stencel sample. It is concluded that the scatter in the absolute magnitudes of the O stars is not as large as found by Garmany & Stencel, and not larger than that of the B stars.
The photochemical reaction center of the bacteriochlorophyll b-containing organism Thiocapsa pfennigii

Abstract A photochemical reaction-center preparation has been made from a second bacteriochlorophyll b-containing organism, Thiocapsa pfennigii. The reaction-center unit is thought to be composed of one P-960, four bacteriochlorophyll, two bacteriopheophytin, one carotenoid molecules and polypeptides of Mr 40000, 37000, 34000, 27000 and 26000 probably plus quinones and metal atoms. The preparation also contains a low-potential cytochrome c-555 and a high-potential cytochrome c-557 bound to the reaction center in a 3–4:2–3:1 molar ratio with respect to P-960. The 40 kDa subunit is associated with the cytochromes, while the 37, 34 and 27 + 26 kDa subunits are proposed to be equivalent to the H, M and L polypeptides of bacteriochlorophyll a-containing reaction centers. The cytochromes are oxidized by P-960+. The three near-infrared absorption bands at 788, 840 and 968 nm are assigned to bacteriopheophytin, bacteriochlorophyll and the primary donor (P-960), respectively. The 778 nm peak resolves into two at 77 K; no further resolution of the other two peaks occurs. Illumination of the sodium dithionite-reduced reaction centers at 77 K by 960 nm-light results in P-960, transferring one electron from cytochrome c-555 mainly to a bacteriopheophytin molecule, absorbing at 781 nm. A similar treatment at room temperatures reduces most of the two bacteriopheophytin molecules. It is argued that both bacteriopheophytin molecules, possibly with some contribution from bacteriochlorophyll, form an intermediary electron-carrier complex between P-960 and a quinone in T. pfennigii. We could not substantiate that a bacteriochlorophyll molecule precedes the bacteriopheophytins in the electron transfer sequence. Although the biochemical characteristics of the reaction center are very similar to those of the other known bacterioclorophyll b-containing reaction center, that from Rhodopseudomonas viridis, their spectral characteristics are not. This has helped elucidate more about the function of each spectral form and led us to conclude that the 850 nm form in Rps. viridis is not the higher energy transition of the special pair of bacteriochlorophyll molecules forming P-960. Laser-flash-in-duced absorbance changes in T. pfennigii reaction-center preparation should now lead to a more complete understanding of the mechanism of the primary photochemical event.
SOX and the regulated firm

Abstract We investigate the initial and long-term market reactions in three regulated industries to the debate and ultimate passage of Sarbanes–Oxley (SOX) legislation. We argue that market reactions may differ for regulated industries relative to the broad market based on perceived differences in the costs and benefits from the legislation. Our results indicate that the initial reaction to the passage was more positive for regulated firms compared with non-regulated firms. These results are generally consistent with a compliance cost based explanation, although the underlying motivation for the results differs across industries. However, over longer post-SOX holding periods, the regulated samples outperformed the S&P 500 but underperformed their matched samples. Lower longer-term accounting profits in terms of ROA argue against significantly lower compliance costs associated with SOX.
Theory of the angular distribution of photoelectrons ejected from optically active molecules and molecular negative ions

It is shown that the angular distribution of photoelectrons ejected on absorption of left or right circularly polarized light by a mixture of randomly oriented dextrorotatory and levorotatory optical isomers behaves as $A\ifmmode\pm\else\textpm\fi{}Bcos\ensuremath{\theta}+C{cos}^{2}\ensuremath{\theta}$, where $\ensuremath{\theta}$ is the angle between the photoelectron momentum and photon direction of incidence and $\ifmmode\pm\else\textpm\fi{} Bcos\ensuremath{\theta}$ is introduced by the presence of unequal numbers of each isomer. All coefficients of ${cos}^{n}\ensuremath{\theta}$ are of order $\ensuremath{\alpha}$, and analysis shows that $B$ can be as large as $A$ and $C$.
Euler's partition theorem and the combinatorics of ℓ-sequences

Euler's partition theorem states that the number of partitions of an integer N into odd parts is equal to the number of partitions of N in which the ratio of successive parts is greater than 1. It was shown by Bousquet-Melou and Eriksson in [M. Bousquet-Melou, K. Eriksson, Lecture hall partitions II, Ramanujan J. 1 (2) (1997) 165-185] that a similar result holds when ''odd parts'' is replaced by ''parts that are sums of successive terms of an @?-sequence'' and the ratio ''1'' is replaced by a root of the characteristic polynomial of the @?-sequence. This generalization of Euler's theorem is intrinsically different from the many others that have appeared, as it involves a family of partitions constrained by the ratio of successive parts. In this paper, we provide a surprisingly simple bijection for this result, a question suggested by Richard Stanley. In fact, we give a parametrized family of bijections, that include, as special cases, Sylvester's bijection and a bijection for the lecture hall theorem. We introduce Sylvester diagrams as a way to visualize these bijections and deduce their properties. In proving the bijections, we uncover the intrinsic role played by the combinatorics of @?-sequences and use this structure to give a combinatorial characterization of the partitions defined by the ratio constraint. Several open questions suggested by this work are described.
Conscious and unconscious detection of semantic anomalies

When asked What superhero is associated with bats, Robin, the Penguin, Metropolis, Catwoman, the Riddler, the Joker, and Mr. Freeze? people frequently fail to notice the anomalous word Metropolis. ...
Computational Soundness of a Call by Name Calculus of Recursively-scoped Records

The paper presents a calculus of recursively-scoped records: a two-level calculus with a traditional call-by-name @l-calculus at a lower level and unordered collections of labeled @l-calculus terms at a higher level. Terms in records may reference each other, possibly in a mutually recursive manner, by means of labels. We define two relations: a rewriting relation that models program transformations and an evaluation relation that defines a small-step operational semantics of records. Both relations follow a call-by-name strategy. We use a special symbol called a black hole to model cyclic dependencies that lead to infinite substitution. Computational soundness is a property of a calculus that connects the rewriting relation and the evaluation relation: it states that any sequence of rewriting steps (in either direction) preserves the meaning of a record as defined by the evaluation relation. The computational soundness property implies that any program transformation that can be represented as a sequence of forward and backward rewriting steps preserves the meaning of a record as defined by the small step operational semantics. In this paper we describe the computational soundness framework and prove computational soundness of the calculus. The proof is based on a novel inductive context-based argument for meaning preservation of substituting one component into another.
Domain-specific bias in arginine/lysine usage by protein toxins

The content of lysine and arginine residues in a number of A-B type protein toxins has been examined. It is found that the A subunit, or its equivalent, often shows a strong bias in the type of basic amino acid residue used tending towards nearly exclusive use of either arginine or lysine rather than use of both, whereas the B subunit or its equivalent shows no such bias. Although arginine codons are GC-rich and lysine codons are AT-rich, the content of GC and AT in the genes coding for the toxins does not adequately explain this bias. Other explanations are discussed, including the possibility that the bias is linked to catalytic function or membrane interaction. Understanding this bias may yield valuable insights into toxin structure and function. Furthermore, identification of bias in sequences may be a useful tool for identifying new toxins and their domains.
Behavioral Treatments of Suicidal Behaviors. Definitional Obfuscation and Treatment Outcomes

This chapter focuses on a review of randomized clinical trials of both psychosocial and behavioral interventions designed to directly reduce rates of suicide and parasuicidal behavior, including suicide attempts. It begins with an overview of the definitional difficulties in this field and then proceeds to an overview of treatment issues and a comprehensive review of treatment studies aiming to reduce suicidal behavior among suicidal individuals. Twenty studies are discussed. Eighteen studies randomly assigned subjects to the experimental and control condition; the other two studies assigned subjects in an alternating sequential fashion. Analyses showed that four psychosocial intervention studies and one pharmacotherapy study have reported efficacious results when compared to treatments-as-usual or placebo controls. From another perspective, when outpatient psychosocial interventions were examined, the strongest predictor of whether the experimental treatment would be more effective than the control was whether high-risk suicidal individuals were included. Psychosocial interventions appear to be most effective with the more high-risk individuals. Language: en
Fabrication of an Extreme Ultraviolet Glancing Incidence Telescope

A technique is described for use in the fabrication of glancing incidence telescopes which operate at large grazing angles (i.e., 8 to 15 degrees). Precision conic section plunge laps are used in a controlled grinding procedure to initially generate imaging surfaces which have a minimum of subsurface damage. A numerically controlled Moore Number 3 Measuring Machine is used throughout the fabrication procedure. Surface geometry accuracies on the order of one-tenth micron have been achieved.
Omnidirectional increase in threshold for image shifts during saccadic eye movements.

The visual system must maintain a stable metric ofvisual space despite changes in the retinal position ofthe world during eye movements. To meet thischallenge, there must be a mechanism for differen­tiating retinal shifts due to eye movement from shiftsdue to the displacement of objects in the world.Whipple and Wallach (1978) have termed this an"accounting" mechanism, while we have previouslydiscussed it as a frame-of-reference computation(Stark, Kong, Schwartz, Hendry, & Bridgeman,1976). This mechanism becomes less sensitive duringtarget displacements due to saccades, an effect whichhas been analyzed experimentally as a saccadic sup­pression of displacement. The failure of subjects todetect target movements occurring during eyemovements, then, provides a tool for investigating themechanism which accomplishes subjective stabiliza­tion.The recent paper of Whipple and Wallach in
Reduction of hepatosteatosis and lipid levels by an adipose differentiation-related protein antisense oligonucleotide.

Background & Aims: Nonalcoholic fatty liver disease (NAFLD) is characterized by excessive triglyceride accumulation in hepatocytes. Expression of the lipid droplet protein adipose differentiation-related protein (ADRP) is increased in NAFLD, but whether this is causally linked to hepatic lipid metabolism is unclear. We postulated that a reduction in ADRP would ameliorate hepatic steatosis and improve insulin action. Methods: Leptin deficient Lepob/ob and diet-induced obese (DIO) mice were treated with antisense oligonucleotide (ASO) against ADRP, and effects on hepatic and serum lipids and glucose homeostasis were examined. Results: ADRP ASO specifically decreased ADRP mRNA and protein levels in the livers of Lepob/ob and DIO mice, without altering the levels of other lipid droplet proteins, that is, S3-12 and TIP47. ADRP ASO suppressed expression of lipogenic genes, reduced liver triglyceride content without affecting cholesterol, attenuated triglyceride secretion, and decreased serum triglyceride and alanine aminotransaminase levels. The reduction in hepatic steatosis by ADRP ASO was associated with improvement in glucose homeostasis in both Lepob/ob and DIO mice. Conclusions: This study demonstrates a crucial role for the lipid droplet protein ADRP in regulation of lipid metabolism. Reduction in hepatic ADRP level using an antisense oligonucleotide reverses hepatic steatosis, hypertriglyceridemia, and insulin resistance in obese mice, suggesting that ADRP may be targeted for the treatment of NAFLD and associated lipid and glucose abnormalities.
Teaching Integrity in Empirical Research: A Protocol for Documenting Data Management and Analysis

This article describes a protocol the authors developed for teaching undergraduates to document their statistical analyses for empirical research projects so that their results are completely reproducible and verifiable. The protocol is guided by the principle that the documentation prepared to accompany an empirical research project should be sufficient to allow an independent researcher to replicate easily and exactly every step of the data management and analysis that generated the results reported in a study. The authors hope that requiring students to follow this protocol will not only teach them how to document their research appropriately, but also instill in them the belief that such documentation is an important professional responsibility.
Theoretical studies of the radical reaction H2CSiH2 + H

Abstract Ab initio molecular orbital calculations on the transition states and barrier heights for the addition of atomic hydrogen to silaethylene are carried out. The activation energy for the addition to the silicon site is lower than that to the carbon site, while the exothermicity is smaller.
Gene Expression and Fast Construction of Distributed Evolutionary Representation

The gene expression process in nature produces different proteins in different cells from different portions of the DNA. Since proteins control almost every important activity in a living organism, at an abstract level, gene expression can be viewed as a process that evaluates the merit or "fitness" of the DNA. This distributed evaluation of the DNA would not be possible without a decomposed representation of the fitness function defined over the DNAs. This paper argues that, unless the living body was provided with such a representation, we have every reason to believe that it must have an efficient mechanism to construct this distributed representation. This paper demonstrates polynomial-time computability of such a representation by proposing a class of efficient algorithms. The main contribution of this paper is two-fold. On the algorithmic side, it offers a way to scale up evolutionary search by detecting the underlying structure of the search space. On the biological side, it proves that the distributed representation of the evolutionary fitness function in gene expression can be computed in polynomial-time. It advances our understanding about the representation construction in gene expression from the perspective of computing. It also presents experimental results supporting the theoretical performance of the proposed algorithms.