cssi/SciSciGPT-SciSciNet huggingface dataset:
Surface Integrals as Symmetry Generators in Supergravity Theory

Abstract It is shown that in asymptotically flat space the weakly vanishing Hamiltonian of supergravity theory has to be modified by adding to it certain surface integrals. The numerical value of the surface integrals yields the total energy-momentum, angular momentum and supercharge of the system. The surface integrals have well defined (Dirac) brackets only after the coordinates and supergauge are fixed. In that case they close according to the flat space supersymmetry algebra. If an internal symmetry is included, new surface integrals appear corresponding to the additional gauge charges.
Wound classification in pediatric general surgery: significant variation exists among providers

Background Risk-adjusted rates of surgical site infections (SSI) are used as a quality metric to facilitate improvement within a hospital system and allow comparison across institutions. The NSQIP-Pediatric, among others, uses surgical wound classification as a variable in models designed to predict risk-adjusted postoperative morbidity, including SSI rates. The purpose of this study was to measure the level of agreement in wound classification assignment among 3 providers: surgeons, operating room (OR) nurses, and NSQIP surgical clinical reviewers (SCR). Study Design An analysis was performed of pediatric general surgery operations from 2010 to 2011. Wound classification was assigned at the time of operation by the OR nurse and surgeon, and by the NSQIP SCR postoperatively, according to NSQIP methodology. Disagreement was defined as any discrepancy in classification among the 3 providers, and the level of agreement was determined using the kappa statistic. Results For the 374 procedures reviewed, there was an overall disagreement of 48% among all providers, kappa 0.48 (95% CI 0.43 to 0.53). When comparing wound classification by surgeon and NSQIP SCR, 23% of cases were in disagreement, kappa 0.74 (95% CI 0.68 to 0.78). Disagreement between OR nurse and either surgeon or NSQIP SCR was higher: 38%, kappa 0.45 (95% CI 0.38 to 0.53) and 40%, kappa 0.44 (95% CI 0.37 to 0.51). Fundoplication, appendectomy, and cholecystectomy demonstrated the highest overall disagreement (73%, 71%, and 60%, respectively). Conclusions There is significant variation in assigning surgical wound classification among health care providers. For future SSI comparative analyses, it will be critical to improve uniformity and understanding of wound class assignment among providers and institutions.
Addition of ethyl diazoacetate to bicyclic olefins

Abstract Several new derivatives of the tricyclo(3.2.1.0 2,4 octane system have been synthesized. The key reaction involved addition of ethyl diazoacetate to norbornenes and norbornadiene.
Existence of solitary internal waves in a two-layer fluid of infinite depth

Abstract : This paper concerns the existence of internal solitary waves moving with a constant speed at the interface of a two-layer fluid with infinite height. The fluids are immiscible, inviscid, and incompressible with constant but different densities. Assume that the height of the upper fluid is infinite and the depth of the lower fluid is finite. It has been formally derived before that under long-wave assumption the first-order approximation of the interface satisfies the Benjamin-Ono equation, which has algebraic solitary-wave solutions. This paper gives a rigorous proof of the existence of solitary-wave solutions of the exact equations governing the fluid motion, whose first-order approximations are the algebraic solitary-wave solutions of the Benjamin-Ono equation. The proof relies on estimates of integral operators using Fourier transforms in L2(R)- space and is different from the previous existence proof of solitary waves in a two-layer fluid with finite depth.
Prenatal and postnatal development of laterally connected orientation maps

Both environmental and genetic factors interact to produce the orientation maps found in the primary visual cortex of adult mammals. However, it is not clear how this interaction occurs during development, or whether both factors are crucial. Previous computational models have focused on either environmentally driven or genetically driven development alone. In contrast, we show that a two-stage model of development can account for a wider range of experimental data. The model explains how environmental and genetic information can be incorporated into the same neural hardware, using a common set of learning mechanisms. Our results suggest that while either environmental or genetically driven development is sufficient for maps and selectivity to form, prenatal activity speeds up early development and makes it more robust against environmental variation.
Comparative effects of ftorafur and 5-fluorouracil on DNA synthesis in rat small intestine.

Abstract The effect of equimolar doses of ftorafur (100 mg/kg) and 5-fluorouracil (65 mg/kg) on the in vivo incorporation of deoxyuridine and thymidine into the DNA of rat small intestine was studied. 5-fluorouracil produced a greater than 90% inhibition of deoxyuridine incorporation within one hour after injection. This degree of inhibition was sustained for at least 12 hours. Deoxyuridine incorporation was inhibited by 30 to 65% during the initial six hours after the injection of ftorafur. By 12 hours the rate of incorporation had returned to 66% of the control value. Neither drug inhibited thymidine incorporation into DNA. A study of the metabolic disposition of radioactively labeled ftorafur and 5-fluorouracil showed that the latter drug was more rapidly and completely converted to fluorouracil-containing nucleotides in the small intestine. The possible relationship between these findings and the reported differences in the toxicity of the two drugs is discussed.
A new manual muscle test for assessing the entire trapezius muscle

Manual muscle testing (MMT), the trapezius muscle is an important part of the examination in patients with upper extremity dysfunction or pain. Purpose: The purpose of this study was to assess the reliability and validity of a new MMT that assesses the entire trapezius muscle instead of the usual method of separating it into three different parts. The new trapezius MMT is similar to the serratus anterior muscle test; however, the testing is performed in the frontal versus sagittal plane. Methods: A convenience sample of 11 subjects was recruited with no known shoulder pathology. Surface electromyography electrodes were placed on the upper, middle, and lower trapezius fibers according to a previously validated method and MMTs for the three different trapezius muscle test positions were normalized against the new trapezius test position. Results: The new trapezius MMT showed very high maximal voluntary isometric contraction (MVIC; 160.80%) for the upper trapezius muscle, high for the middle trapezius muscle...
Risk stratification post-myocardial infarction: is early coronary angiography the more effective strategy?

The primary management strategy for the post-myocardial infarction patient continues to be controversial despite published guidelines. In part, this is the consequence of study designs that are not directly applicable to individual patients, but also to the rapidly changing pharmacological and mechanical device armamentarium that rapidly renders clinical trial results obsolete within a few years. This review attempts to highlight those areas where there is consensus as well as to explicate those situations where common clinical practice appears to be in conflict with accepted guidelines.
The size of LALR (1) parsers

Simple statistical formulas are given for the size of an LALR(1) parser. For practical grammars the number of states of an LALR(1) parser is linear with grammar size.
The Prosthesis Salvage Operation: Immediate Replacement of the Infected Penile Prosthesis

AbstractPurpose: We describe our experience with salvage of the infected penile prosthesis at initial presentation in 11 patients.Materials and Methods: All patients with prosthesis infection who presented since 1991 were considered for salvage surgery. Contraindications to a salvage operation included necrotic infections, diabetic patients with purulence in the corporeal bodies, rapidly developing infections and erosion of the device cylinders.Results: In 1 patient in this group a salvage attempt was repeated after re-infection, for an overall success rate of 91 percent. Mean followup for the group was 21 months (range 9 to 42). Staphylococcus epidermidis was the infecting organism in 75 percent of out patients.Conclusions: Our experience demonstrates the safety and advantages of the immediate salvage technique.
Geometries of frontal fold and thrust belts: Insights from discrete element simulations

Abstract This study investigated the evolution of frontal structures of fold and thrust belts with 2D numerical simulations using the discrete element method (DEM). Of specific interest is the occurrence of triangle zones, and how mechanical stratigraphy affects the formation of the triangle zones. In our simulations, we varied the strength of a two unit stratigraphy, as well as the decollement horizons, to determine the controlling parameters of different types of frontal structures. For models with homogenous stratigraphy, deformation was concentrated along forethrusts, which involved both the upper and lower units. With the addition of a mechanically weak upper unit, deformation along forethrusts and popup structures largely occurred in the upper unit with relatively little deformation of the lower unit. With thicker decollement surfaces and strong upper and lower units, decoupling was enhanced and allowed for the formation of triangle zones in front of the deforming wedge. The triangle zones were uplifted along lower forethrusts, until a new frontal triangle zone formed. Results compared favorably with triangle zones found in the Canadian Cordillera in southern Alberta.
Quantitative analysis of sphingolipids for lipidomics using triple quadrupole and quadrupole linear ion trap mass spectrometers

Sphingolipids are a highly diverse category of bioactive compounds. This article describes methods that have been validated for the extraction, liquid chromatographic (LC) separation, identification and quantitation of sphingolipids by electrospray ionization, tandem mass spectrometry (ESI-MS/MS) using triple quadrupole (QQQ, API 3000) and quadrupole-linear-ion trap (API 4000 QTrap, operating in QQQ mode) mass spectrometers. Advantages of the QTrap included: greater sensitivity, similar ionization efficiencies for sphingolipids with ceramide versus dihydroceramide backbones, and the ability to identify the ceramide backbone of sphingomyelins using a pseudo-MS3 protocol. Compounds that can be readily quantified using an internal standard cocktail developed by the LIPID MAPS Consortium are: sphingoid bases and sphingoid base 1-phosphates, more complex species such as ceramides, ceramide 1-phosphates, sphingomyelins, mono- and di-hexosylceramides, and these complex sphingolipids with dihydroceramide backbones. With minor modifications, glucosylceramides and galactosylceramides can be distinguished, and more complex species such as sulfatides can also be quantified, when the internal standards are available. JLR LC ESI-MS/MS can be utilized to quantify a large number of structural and signaling sphingolipids using commercially available internal standards. The application of these methods is illustrated with RAW264.7 cells, a mouse macrophage cell line. These methods should be useful for a wide range of focused (sphingo)lipidomic investigations.
GPS and Airborne Gravimetry: Recent Progress and Future Plans

The logistical difficulties and expense of measuring gravity over the surface of the earth or ocean provides the motivation for developing techniques for airborne data acquisition. To meet this need, the U.S. Naval Research Laboratory (NRL) has had an active research program in airborne gravimetry since 1979. This paper provides a brief history, current status and proposed future directions of the program.
Applying pattern recognition methods to analyze the molecular properties of a homologous series of nitrogen mustard agents.

The purpose of this research was to analyze the pharmacological properties of a homologous series of nitrogen mustard (N-mustard) agents formed after inserting 1 to 9 methylene groups (-CH2-) between 2-N(CH2CH2Cl)2 groups. These compounds were shown to have significant correlations and associations in their properties after analysis by pattern recognition methods including hierarchical classification, cluster analysis, nonmetric multi-dimensional scaling (MDS), detrended correspondence analysis, K-means cluster analysis, discriminant analysis, and self-organizing tree algorithm (SOTA) analysis. Detrended correspondence analysis showed a linear-like association of the 9 homologs, and hierarchical classification showed that each homolog had great similarity to at least one other member of the series—as did cluster analysis using paired-group distance measure. Nonmetric multi-dimensional scaling was able to discriminate homologs 2 and 3 (by number of methylene groups) from homologs 4, 5, and 6 as a group, and from homologs 7, 8, and 9 as a group. Discriminant analysis, K-means cluster analysis, and hierarchical classification distinguished the high molecular weight homologs from low molecular weight homologs. As the number of methylene groups increased the aqueous solubility decreased, dermal permeation coefficient increased, Log P increased, molar volume increased, parachor increased, and index of refraction decreased. Application of pattern recognition methods discerned useful interrelationships within the homologous series that will determine specific and beneficial clinical applications for each homolog and methods of administration.
The accuracy of an ear face-bow.

Abstract A study was conducted comparing the accuracy of a new arbitrary face-bow method and a conventional arbitrary method with a true hinge axis technique. A standardized method of recording the location of the various points was described. Of the 94 different axis locations registered, 33 per cent of the conventional axis locations were within 6 mm. of the true axis, as compared to 56.4 per cent located by the ear face-bow.
Physostigmine, tacrine and metrifonate: The effect of multiple doses on acetylcholine metabolism in rat brain

The effects of two consecutive intramuscular doses of three cholinesterase inhibitors (physostigmine, tetrahydroaminoacridine and metrifonate) were compared in rats. The results revealed major differences in biochemical effects on the brain of the rat including the extent and duration of inhibition of cholinesterase, inhibition of release of acetylcholine and increase in levels of acetylcholine. Side effects were also markedly different in the time of appearance, duration and severity. These results suggest that there are significant differences in the mechanisms of action of various cholinesterase inhibitors. Since all three cholinesterase inhibitors are currently used in the experimental treatment of Alzheimer's disease, these findings have potential implications for the symptomatic therapy of these patients.
Cyclic Olefin Resist Polymers and Polymerizations for Improved Etch Resistance.

This paper will describe the strengths and unique challenges of building 193nm resists from acrylic polymers and cyclic olefin polymers. In particular, cyclic olefin (alternating) copolymer synthesis and properties will be discussed.
Finite-state phrase parsing by rule sequences

We present a novel approach to parsing phrase grammars based on Eric Brill's notion of rule sequences. The basic framework we describe has somewhat less power than a finite-state machine, and yet achieves high accuracy on standard phrase parsing tasks. The rule language is simple, which makes it easy to write rules. Further, this simplicity enables the automatic acquisition of phrase-parsing rules through an error-reduction strategy.
Regional gene therapy with a BMP‐2‐producing murine stromal cell line induces heterotopic and orthotopic bone formation in rodents

The ability to continuously deliver osteoinductive proteins to a specific anatomic site would facilitate the treatment of fracture nonunions and other clinical problems associated with bone loss. We have developed a murine model of regional gene therapy. A bone-marrow stromal cell line infected with an adenovirus expressing recombinant bone morphogenetic protein-2 cDNA secreted biologically active bone morphogenetic protein-2. These bone morphogenetic protein-2-producing cells were able to induce abundant heterotopic bone formation when implanted into the quadriceps muscle of severe combined immune deficient mice and also successfully healed large segmental femoral defects in nude rats. These studies demonstrate that regional gene therapy with continuous delivery of osteoinductive factors to a specific anatomic site can enhance the formation and repair of bone.
Wastewater reclamation, recycling and reuse: past, present, and future

The scientific basis for the current status of wastewater reclamation, recycling and reuse has evolved from developments in water and wastewater engineering coupled with increasing pressures on water resources. Milestone events that have led to the safe use of reclaimed wastewater are reviewed. The role of engineered systems associated with reclaimed wastewater is discussed in the context of the natural hydrologic cycle. A synopsis of the significant studies that form the basis for current regulatory approaches and technological innovations is presented. Current water reclamation strategies incorporate multiple measures to minimize health and environmental risks associated with various reuse applications. A combination of source control, advanced treatment process flowschemes, and other engineering controls provides a sound basis for increased implementation of water reuse applications. The feasibility of producing reclaimed water of a specified quality to fulfill multiple water use objectives is now a reality due to the progressive evolution of technologies and risk assessment procedures. Future water reuse directions are charted.
Cr-hollandite: Breaking tradition with todorokite-type manganese oxides

Abstract The synthesis of a tunneled hollandite-type manganese oxide with interstitial and framework Cr 3+ is described. This unique material is prepared from a layered buserite precursor under conditions previously believed to only yield todorokite-type manganese oxides with larger tunnels. The influence of Cr 3+ in promoting the hollandite structure has been investigated by selectively placing the cation either in interstitial or framework sites. The use of framework Cr 3+ in combination with other interstitial cations generates related hollandite and todorokite derivatives. Catalytic oxidation reactions with benzyl alcohol and carbon monoxide have also been examined.
Matrix formulation of co-kriging

The matrix form of the general co-kriging problem is presented. Matrix solutions are given for SRFs with covariance functions, for IRFs of order zero using variograms and for universal co-kriging. General methods for obtaining cross-covariance or cross-variogram models are given. The relationship of the general co-kriging problem to the problem of one under sampled variable is presented.
A ring chromosome No. 16 in an infant with primary hypoparathyroidism

A male infant whose clinical features included hypertelorism epicanthic folds, beak-shaped nose, high-arched palate, micrognathia, low-set ears with slit-like openings of the external auditory canal, and bilateral cryptorchidism was found to have a ring chromosome No. 16. Hypoparathyroidism was diagnosed at 4 1/2 months of age. The proband had four different cell populations associated with the instability of the ring chromosome. The haptoglobin, Kell, Duffy, and Rh loci were not in the deleted portions of chromosome No. 16. The possible relationship of the chromosomal abnormality to hypoparathyroidism is discussed.
Biophysics of P2X receptors

The P2X receptor is the baby brother of the ligand-gated ion channel super-family. An understanding of its role in human physiology is still developing, and no one truly knows how it works to transport ions across the membrane. In this study, we review some aspects of P2X channel biophysics, concentrating on ion permeation and gating. P2X channels transport both small and large cations and anions across cell membranes in a manner that depends on both the subunit composition of the receptor and the experimental conditions. We describe the pore properties of wild-type receptors and use the altered phenotypes of mutant receptors to point the way towards a structural model of the pore.
Feeding on protists and particulates by the leptocephali of the worm eels Myrophis spp. (Teleostei: Anguilliformes: Ophichthidae), and the potential energy contribution of large aloricate protozoa

The food sources of the leptocephali of the teleostean superorder Elopomorpha have been controversial, yet observations on the leptocephali of the worm eels, Myrophis spp. (family Ophichthidae) collected in the northern Gulf of Mexico indicate active, not passive, feeding. Leptocephali had protists in their alimentary canals. Estimates of the physiological energetics of worm eels indicate that large aloricate protozoa including ciliates could provide substantial energy to these leptocephali toward the end of the premetamorphic and metamorphic stages, given the low energy requirements of metamorphosing leptocephali. Global ocean warming will likely force a shift in oceanic food webs; a shift away from large protozoa toward smaller protists is possible. Such a disruption of the oceanic food webs could further compromise the survival of leptocephali.
Intrasubject variation in sustained-release theophylline absorption

Abstract Intrasubject variability in the absorption characteristics of two sustained-release theophylline products was examined. Eight healthy, nonsmoking, adult volunteers received a single 250 mg Slo-Phyllin Gyrocap on two separate study days and a single 304 mg Theo-due tablet on two other study days. Plasma samples were collected over a 24-hr period after each dose and were assayed for theophylline content. Absorption parameters were determined, including peak plasma concentration, peak time, absorption rate; time until 94% absorbed, and area under the plasma concentration time curve. Marked intrasubject variation in these absorption parameters was found by examination of duplicate plasma concentration time curves. These differences are not apparent from examination of mean data only. The implications of this dose-to-dose variation for the individual patient are discussed.
Strategic Management and the Straightjacket: An Editorial Essay

Research output in strategic management has enjoyed enormous growth over the last two decades. As a scholar in strategic management, I find growth of the field to be gratifying. However, as a frequent field observer of large firms, I am often struck by the sense that most of this research is irrelevant to what is going on in such firms today. This is most troubling when I reflect on the seeming modest impact research in strategic management has had on either practice or government policy. By contrast, financial economists have significantly influenced the national debate on U.S. firms and international competitiveness in the 1980's, and much of their research has found ready application on Wall Street. This is likely due to their willingness to both address issues of relevance today and make forceful prescriptive recommendations. In this regard topics such as LBO's, hostile takeovers, junk bonds, executive compensation, corporate governance, acquisitions, divestitures, and government intervention in security markets come to mind. I believe that scholars in strategic management could have had much of great value to say about many of these topics in the 1980's, especially international competitiveness. Furthermore, these largely unheard voices disagreed substantially with the recommendations of financial economists. Why has the proliferation of research in strategic management not been accompanied by increasing impact? Like the editors of this journal (Daft and Lewin 1990) have observed about organization studies generally, I feel that much research in strategic management seems increasingly and prematurely stuck in a "normal science straightjacket." As Daft and Dr. Buenger (1990) put it, "strategic management has been ensnared by the rituals and paraphernalia of normal science" (p. 82). The purpose of this essay is to discuss some specific aspects of this evolving "straightjacket" for strategic management and make some pragmatic proposals for breaking free. It is intended as editorial comment (i.e., opinion) not scholarly analysis. Certainly some, and perhaps many, in the field will disagree with what I say. At the same time, I know that many will agree. Hopefully, the essay will help stimulate further reflective thinking in the field. If it does this it will have achieved its goal. I accept the assertion that research in strategic management should have relevance to understanding actual managers, actual strategic decisions, actual businesses units, actual firms, and actual industries as they exist today or are likely to exist in the future. I further believe that the results of this research should ultimately find important application in both industry and government. There are several aspects of research in strategic management that seem to contribute to what Daft and Lewin call a "sense of irrelevance" and "incremental, footnote-on-footnote research." Much current research is based on concepts developed decades ago on the basis of studies of firms as they and their environments were
Scaling of confinement with major and minor radius in the Tokamak Fusion Test Reactor.

Plasma-size scans have been performed in the Tokamak Fusion Test Reactor to investigate the effect of major and minor radius upon energy confinement in high-recycling plasmas heated by neutral-beam injection. The major radius, minor radius, and aspect ratio were varied over a large range ({ital a}=0.4--0.9 m, {ital R}=2.08--3.2 m, {ital R}/{ital a}=2.8--8.0). The energy confinement measured with diamagnetic and kinetic diagnostics scales strongly with major radius, and weakly or negatively with minor radius.
Three-dimensional anisotropic physical optics modeling of three-wave mixing

A three-wave mixing crystal is an anisotropic material. To model beam propagation through such a medium, one must have a propagator which includes the anisotropic effects, such as walkoff, in addition to the usual diffraction effect. This requirement leads to the specific exponential forms appearing in the set of coupled differential equations we use to model the nonlinear coupling. In this paper, three coupled beams in two transverse dimensions (i.e., with arbitrary initial cross sections) are propagated through an anisotropic three-wave mixing crystal with their bulk absorption and surface losses included. We present the theory of anisotropic propagation and the field coupling of three wave-mixing, including phase matching/mismatching. Results from the full numerical simulations are compared with experimental data. Our numerical approach avoids a number of simplifications common in analytical treatments, thereby providing more realistic modeling of experimental situations.
Tetragonal Iron Sulfide

Studies of synthetic iron sulfides formed from aqueous solution at 25°C and atmospheric pressure have revealed the existence of a new phase, tetragonal FeS. This phase is formed as the initial corrosion product of metallic iron or steel in solutions of hydrogen sulfide. It has been discovered as an iron corrosion product in the sediments of the Mystic River at Boston, Massachusetts.
Recombinant juvenile hormone esterase, an effective tool for modifying juvenile hormone-dependent expression of the early trypsin gene in mosquitoes

The study of the changes in the steady-state levels of the early trypsin (ET) messenger RNA (mRNA) was used as a sensitive assay for measuring the effects of recombinant juvenile hormone esterase (rJHE) on juvenile hormone (JH)-dependent gene expression in mosquitoes. ET is a female-specific protease present in the midgut of the yellow fever mosquito Aedes aegypti during the first few hours after ingestion of a blood meal. Transcription of the early trypsin gene is part of the normal postemergence maturation of the midgut in the adult female, and it is regulated by JH. JHE was cloned from Heliothis virescens and expressed in a baculovirus vector. Injection of rJHE into mosquitoes resulted in an increase of JHE activity in the haemolymph. Injection of rJHE into newly emerged adult females delayed the normal increase in steady-state levels of ET mRNA observed in controls. Topically applied methoprene (a JH analogue) reversed the effect of rJHE. Injection of increasing concentrations of rJHE into 3-day-old unfed females resulted in a dose-dependent decrease in the steady-state levels of ET mRNA after 24 h. The effect of rJHE was transient, once the enzyme was cleared (72 h after injection), the steady-state levels of ET mRNA were restored. The injection of rJHE is an effective tool for modifying JH-dependent expression of the early trypsin gene in mosquitoes.
Aortic atheroma is related to outcome but not numbers of emboli during coronary bypass

Background. The relation between aortic atheroma severity and stroke after coronary artery bypass grafting is established. The relation between atheroma severity and other outcome measures or numbers of emboli has not been determined. Methods. Using transesophageal echocardiography, we determined the severity of atheroma in the ascending, arch, and descending aortic segments in 84 patients undergoing operations. Seventy patients were monitored using transcranial Doppler ultrasonography. Results. The incidence of stroke was 33.3% among 9 patients with mobile plaque of the arch and 2.7% among 74 patients with nonmobile plaque ( p = 0.011). Cardiac complications were not significantly related to atheroma severity in any aortic segment. Length of stay was significantly related to atheroma severity in the aortic arch ( p = 0.025) and descending segment ( p = 0.024). The presence of severe atheroma in both the arch and descending segments was associated with significantly longer hospital stays as compared with patients with severe atheroma in neither segment ( p = 0.05). Numbers of emboli were greater in patients with severe atheroma at clamp placement, although the differences did not achieve statistical significance. Conclusions. Aortic atheroma severity is related to stroke and to the duration of hospitalization after coronary artery bypass grafting. The lack of correlation between numbers of emboli and atheroma severity suggests that many emboli may be nonatheromatous in nature.
Forced copulation as a conditional alternative strategy in camel crickets

In the animal kingdom, males typically acquire reproductive access to females through courtship, nuptial gifts, or combat. In many species, small or poor-condition males that are unable to produce an attractive display, proffer an adequate mating gift, or dominate in male–male competition may resort to forced copulation. Forced copulation has been previously demonstrated in the camel cricket Pristoceuthophilus marmoratus and is uniquely facilitated by male hind leg weaponry that functions in both intrasexual competition and sexual coercion. Because male leg armaments are positively allometric, the largest males would seem best equipped to force-copulate, although they might be the most attractive to females, and so least likely to adopt a forced copulation strategy. In order to resolve this potential paradox and determine which males are in fact most likely to force-copulate, we manipulated male body size using diet and performed mating trials. Results showed that (1) male size increased with diet quality, (2) females appear to prefer larger males, and (3) smaller males were more likely to attempt forced copulation. Our results thus suggest that forced copulation is a condition-dependent alternative mating tactic used by small males unattractive to females.
Gyrase and Topo IV modulate chromosome domain size in vivo

In bacteria, DNA supercoil movement is restricted to subchromosomal regions or 'domains.' To elucidate the nature of domain boundaries, we analysed reaction kinetics for gammadelta site-specific resolution in six chromosomal intervals ranging in size from 14 to 90 kb. In stationary cultures of Salmonella typhimurium, resolution kinetics were rapid for both short and long intervals, suggesting that random stationary barriers occur with a 30% probability at approximately 80 kb intervals along DNA. To test the biochemical nature of domain barriers, a genetic screen was used to look for mutants with small domains. Rare temperature-sensitive alleles of DNA gyrase and Topo IV (the two essential type II topoisomerases) had more supercoil barriers than wild-type strains in all growth states. The most severe gyrase mutants were found to have twice as many barriers in growing cells as wild type throughout a 90 kb interval of the chromosome. We propose that knots and tangles in duplex DNA restrain supercoil diffusion in living bacteria.
Selective versus comparative processing

Abstract Simonson et al. (forthcoming) propose a new theory of comparison selection that explains which particular alternatives will be considered in a wide variety of judgment and choice tasks. Comparison selection depends on the latitude of acceptance, comparison fluency, and the interaction between these factors. Importantly, these factors integrate a wide variety of seemingly unrelated variables, and the theory is useful for generating novel hypotheses. However, because comparative processing occurs relatively infrequently, it is important to take a step back and specify the conditions under which comparative processing is likely to occur. Comparative processing is likely only when the motivation and the opportunity to process information carefully are high, when consumers lack knowledge about distributional standards, or when stimulus-based judgment is likely. The two types of processes have different antecedents, consequences, and implications for debiasing.
Fossil wood in coal-forming environments of the late Paleocene-early Eocene Chickaloon Formation.

The early Cenozoic Chickaloon Formation is the main coal-bearing sequence in south-central Alaska. Coal and associated plant macrofossils are well exposed in the Eska, Premier, and Jonesville Coal Groups in the Wishbone Hill District. There is a striking variation in the degree and mode of preservation of fossil trees in a vertical sequence through these coal groups. We examined the wood taxonomy, mineralogy, and geochemistry to elucidate potential cause(s) for these differences. The wood anatomy indicates that the wood is all assignable to the Cupressaceae (Taxodiaceae s.str.) and assignable to the form genus Taxodioxylon Hartig emend. Gothan. However, we found no significant variation in the taxonomy of the wood between stratigraphic layers. The wood generally becomes better preserved in the Jonesville Coal Group. Wood from the stratigraphically lower Premier Coal Group exhibits greater plastic deformation and contains less well-preserved wood anatomical features. The wood from the overlying Jonesville Coal Group retains most of its original morphology, but has suffered from brittle fracture. The geochemistry and mineralogy of the wood follow a pattern that corresponds to the degree of preservation. The less well-preserved wood tends to have a higher concentration of iron carbonate minerals (e.g., siderite and ankerite), whereas the better preserved wood contains more calcium carbonate or silica. All evidence points to rapid permineralization of the original wood, although the least well-preserved wood shows evidence of greater organic matter decomposition than the better preserved wood. The wood taxonomy and mode of preservation of wood from the upper part of the Chickaloon Formation is similar to wood from coeval fossil forests that developed at higher (polar) paleolatitudes.
Estimation of the confidence limits of oligonucleotide-array-based measurements of differential expression

Microarrays can be used to simultaneously measure the differential expression states of many mRNA's in two samples. Such measurements are limited by systematic and random errors. Systematic errors include labeling bias, imperfect feature morphologies, mismatched sample concentrations, and cross-hybridization. Random errors arise from chemical and scanning noise, particularly for low signals. We have used a combination of fluor-exchanged two-color labeling and improved normalization methods to minimize systematic errors from labeling bias, imperfect features, and mismatched sample concentrations. On-array specificity control probes and experimentally proven probe design algorithms were used to correct for cross-hybridization. Random errors were reduced via automated non-uniform feature flagging and an advanced scanner design. We have scored feature significance, using established statistical tests. We have then estimated the intrinsic random measurement error as a function of average probe signal via sample self-comparison experiments (human K-562 cell mRNA). Finally, we have combined all of these tools in the analysis of differential expression measurements between K-562 cells and HeLa cells. The results establish the importance of the elimination of systematic errors and the objective assessment of the effects of random errors in producing reliable estimates of differential expression.
An Idealized Comparison of One-Way and Two-Way Grid Nesting

Abstract Most mesoscale models can be run with either one-way (parasitic) or two-way (interactive) grid nesting. This paper presents results from a linear 1D shallow-water model to determine whether the choice of nesting method can have a significant impact on the solution. Two-way nesting was found to be generally superior to one-way nesting. The only situation in which one-way nesting performs better than two-way is when very poorly resolved waves strike the nest boundary. A simple filter is proposed for use exclusively on the coarse-grid values within the sponge zone of an otherwise conventional sponge boundary condition (BC). The two-way filtered sponge BC gives better results than any of the other methods considered in these tests. Results for all wavelengths were found to be robust to other changes in the formulation of the sponge boundary, particularly with the width of the sponge layer. The increased reflection for longer-wavelength disturbances in the one-way case is due to a phase difference bet...
A cancer-associated lactate dehydrogenase is expressed in normal retina

An unusual isozyme of lactate dehydrogenase, lactate dehydrogenase k, is found in high concentrations in cultured cells transformed by the Kirsten murine sarcoma virus and in many human cancer tissues. In experiments described here high levels of a lactate dehydrogenase k activity were detected in extracts of normal rodent retina. This activity had the same key properties as the human tumor isozyme, namely, a highly cathodic electrophoretic mobility and inhibition of enzymatic activity by oxygen and 5',5'-dipurinenucleoside tetraphosphates. Expression of this activity in the retina may be related to the high aerobic glycolysis characteristic of the retina, a metabolic feature shared with many tumors.
The effects of alcohol on cyclic AMP in mouse brain

Detailed analysis of the dose-response and time-course relationship of ethanol to changes in adenosine 3′,5′-cyclic monophosphate (cAMP) content of mouse brain revealed several patterns of response, including both decreases and increases depending on brain area. Whole-brain cAMP content was decreased with ethanol injection at all doses (0.4–3.2 g/kg), and reflected the decreased levels in the cortex. The subcortical and cerebellar levels underwent a significant increase with doses of 1.6 and 3.2 g/kg, respectively. In all brain areas, significant changes in cAMP content occur within 10 min after ethanol injection; elevated levels persist for 30–60 min in the subcortex and cerebellum, but remain significantly depressed in the cortex at 3 h. These dynamic changes in brain cAMP levels after ethanol administration may reflect variations in neurotransmitter activity.
Ventricular Constraint Using the Acorn Cardiac Support Device Reduces Myocardial Akinetic Area in an Ovine Model of Acute Infarction

Background Left ventricular remodeling secondary to acute myocardial infarction (AMI) is characterized by ventricular dilatation and regional akinesis. In this study, we investigated the effect of passive constraint on akinetic area development. Methods and Results The effect of passive constraint on akinetic area was investigated in 10 sheep using tissue-tagging magnetic resonance imaging (MRI). A baseline MRI study was followed by the creation of an anterior infarct. After 1 week, the animals received a second MRI study. A cardiac support device (CSD) was then placed over the epicardium in 5 sheep whereas the remaining animals served as controls. A terminal study was performed at the 2-month postinfarct in both groups. The akinetic area at 1-week postinfarct was similar in both groups. At the terminal time-point, the akinetic area in the control group was similar to the 1-week time-point whereas in the CSD group, the area of akinesis decreased ( P= 0.001). A comparison of the 2 groups at the terminal time-point demonstrates a significantly diminished area of akinesis in the CSD group ( P= 0.004). The relative area of akinesis followed a similar pattern. End-systolic and end-diastolic wall thickness was significantly greater in the CSD group at terminal ( P= 0.001). In addition, the minimum wall thickness was greater in the CSD group compared with the controls ( P= 0.04). Conclusions Passive constraint reduced akinetic area development secondary to AMI. The attenuation of regional wall stress may prevent the incorporation of the border zone into the infarct, decreasing infarct size and providing a promising new therapy for patients after an AMI.
From natural products to biological tools

The development of a total synthetic approach for the antimitotic disorazole C 1 and the design of a peptide isostere linked to the reactive oxygen scavenger 2,2,6,6-tetra- methylpiperidine-N-oxyl (TEMPO) demonstrate established as well as novel strategies for mining the therapeutic potential of natural products.
Vascular risk factors and longitudinal changes on brain MRI: The ARIC study

Objective: To evaluate associations between vascular risk factors and changes in burden of infarcts, ventricular size (VS), sulcal widening (SW), and white matter hyperintensities (WMH) in an initially middle-aged, biracial cohort from the Atherosclerosis Risk in Communities (ARIC) study. Methods: Initial brain magnetic resonance (MR) scans and evaluations for vascular risk factors were performed in 1,812 ARIC participants in 1994–1995. In 2004–2006, 1,130 ARIC participants underwent repeat MR scans. MR scans were rated using a validated 9-point scale for VS, SW, and WMH. Infarcts were recorded. Multiple logistic regression analysis was used to assess associations between vascular risk factors and change between MR scans of one or more grades in VS, SW, WMH, or appearance of new infarcts, controlling for age, sex, and race. Results: At baseline, the 1,112 participants with usable scans (385 black women, 200 black men, 304 white women, 223 white men) had a mean age of 61.7 ± 4.3 years. In adjusted models, diabetes at baseline was associated with incident infarcts (odds ratio [OR] 1.95, 95% confidence interval [CI] 1.29–2.95) and worsening SW (OR 2.10, 95% CI 1.36–3.24). Hypertension at baseline was associated with incident infarcts (OR 1.73, 95% CI 1.23–2.42). In subjects with the highest tertile of fasting blood sugar and systolic blood pressure at baseline, the risk of incident infarcts was 3.68 times higher (95% CI 1.89–7.19) than those in the lowest tertile for both. Conclusion: Both atrophic and ischemic imaging changes were driven by altered glycemic and blood pressure control beginning in midlife.
Aminoacyl-tRNA synthetase-induced cleavage of tRNA

Abstract Aminoacyl-tRNA synthetases interact with their cognate tRNAs in a highly specific fashion. We have examined the phenomenon that upon complex formation E. coli glutaminyl-tRNA synthetase destabilizes tRNA(Gln) causing chain scissions in the presence of Mg2+ ions. The phosphodiester bond cleavage produces 3'-phosphate and 5'-hydroxyl ends. This kind of experiment is useful for detecting conformational changes in tRNA. Our results show that the cleavage is synthetase-specific, that mutant and wild-type tRNA(Gln) species can assume a different conformation, and that modified nucleosides in tRNA enhance the structural stability of the molecule.
UCSC on REC 2006 Blog Opinion Mining.

The University of California Santa Cruz team submitted three runs for the TREC Blog Track opinion mining task. We developed a two stage retrieval system. We started with retrieving relevant documents from the corpus for each topic, and then ran each retrieved document through a classifier to estimate the probability that the document contains opinion expressions. The documents were ranked according to the product of the retrieval score and the estimated probability. The Lemur search engine, which is based on the language modeling approach, was used for retrieval. A Bayesian Logistic Regression classifier was trained using a noisy training data set from other domains, which include news articles, product reviews and movie reviews. All runs are automatic.
Trypanosoma brucei RNA binding proteins p34 and p37 mediate NOPP44/46 cellular localization via the exportin 1 nuclear export pathway.

We have previously identified and characterized two novel nuclear RNA binding proteins, p34 and p37, which have been shown to interact with a family of nucleolar phosphoproteins, NOPP44/46, in Trypanosoma brucei . These proteins are nearly identical, the major difference being an 18-amino-acid insert in the N terminus of p37. In order to characterize the interaction between p34 and p37 and NOPP44/46, we have utilized an RNA interference (RNAi) cell line that specifically targets p34 and p37. Within these RNAi cells, we detected a disruption of a higher-molecular-weight complex containing NOPP44/46, as well as a dramatic increase in nuclear NOPP44/46 protein levels. We demonstrated that no change occurred in NOPP44/46 mRNA steady-state levels or stability, nor was there a change in cellular protein levels. These results led us to investigate whether p34 and p37 regulate NOPP44/46 cellular localization. Examination of the p34 and p37 amino acid sequences revealed a leucine-rich nuclear export signal, which interacts with the nuclear export factor exportin 1. Immune capture experiments demonstrated that p34, p37, and NOPP44/46 associate with exportin 1. When these experiments were performed with p34/p37 RNAi cells, NOPP44/46 no longer associated with exportin 1. Sequential immune capture experiments demonstrated that p34, p37, NOPP44/46, and exportin 1 exist in a common complex. Inhibiting exportin 1-mediated nuclear export led to an increase in nuclear NOPP44/46 proteins, indicating that they are exported from the nucleus via this pathway. Together, our results demonstrate that p34 and p37 regulate NOPP44/46 cellular localization by facilitating their association with exportin 1.