cssi/SciSciGPT-SciSciNet huggingface dataset:
Organization of the 3'-terminal half of beet yellow stunt virus genome and implications for the evolution of closteroviruses.

Abstract The 3′-terminal half of the beet yellow stunt virus (BYSV) genome, 10,545 nt, has been cloned and sequenced. The sequenced portion of the BYSV genome encompasses 10 open reading frames (ORFs) and 241 nt of the 3′ untranslated region. The sequence spans, in the 5′ to 3′ direction, the C-terminal region of the replication-associated polyprotein gene (ORF 1a) which includes the set of motifs typical of helicases (HEL), the entire 53-kDa polymerase (RdRp) gene (ORF 1b), and genes encoding 30-kDa (ORF 2), 6-kDa (ORF 3), 66-kDa (ORF 4), 61-kDa (ORF 5), 25-kDa (ORF 6), 23.7-kDa (coat protein, CP) (ORF 7), 18-kDa (ORF 8), and 22-kDa (ORF 9) proteins. The double-stranded RNA “replicative form” of the BYSV was demonstrated to have a nontemplate G residue at the 3′ terminus of the (+) strand. The RdRp of BYSV is presumably expressed via a +1 ribosomal frameshift. The five-gene module conserved among closteroviruses was identified in BYSV; it includes a gene array coding for a 6-kDa small hydrophobic protein, a 66-kDa homolog of the cellular HSP70 heat shock proteins, a 61-kDa protein, and a 25-kDa diverged copy of the CP followed by the CP gene itself. Phylogenetic analysis of the replication-associated HEL and RdRp domains as well as proteins from the five-gene module demonstrated the closest relationship between BYSV and two other closteroviruses, beet yellows (BYV) and citrus tristeza (CTV) viruses. Like CTV, the BYSV genome contains a 30-kDa protein gene between the RdRp and the 6-kDa protein genes, and like BYV it has only two genes downstream of the CP gene. The organization of the BYSV genome appears to be intermediate between BYV and CTV, which suggests that these three viruses might represent three distinct but probably close stages in the closterovirus evolution.
Estimation of critical pressures by the rackett equation

Abstract Two methods for calculating critical pressure ( P c ) values from liquid density data by using the Rackett equation are proposed. The reliability of these methods is discussed on the basis of the results obtained by predicting the P c values of nearly 100 organic compounds which are representative of many structural types. Several strategies to improve the accuracy of the proposed methods are also discussed.
The anyon fluid in the Bogoliubov approximation.

We study the free anyon fluid by extending the usual Bogoliubov approximation to the case of nonlocal "statistical" interactions. We thereby compute the ground-state energy, the spectrum of low-lying excitations, the static structure factor, and the pair distribution function. The ground-state energy depends crucially on the magnetic dimension of the anyons, a scale that is unavoidably present at the quantum level. The linearly dispersing collective mode in the excitation spectrum indicates superfluidity.
Evaluation of the use of buprenorphine for opioid withdrawal in an emergency department.

Objectives: To examine the use of buprenorphine for the treatment of opioid withdrawal (OW) in an emergency department (ED) setting. Methods: The medical records of all adult patients who presented to the study ED during a 10 week period for OW were abstracted. Subjects were categorized as receiving buprenorphine, symptomatic treatment or no pharmacologic treatment for their OW. The three groups were compared by patient and service characteristics, withdrawal symptoms and outcomes. Results: Of the 11,019 patients who presented to the ED during the 10 week study period, 158 (1.4%) were eligible. Subjects were more likely to receive buprenorphine (56%) compared to symptomatic treatment only (26%) or no pharmacologic treatment (18%). Subjects who received buprenorphine were more likely to have a history of suicide ideation (34% versus 12% p < 0.05) compared to subjects who received symptomatic treatment(s) and were less likely to present with a gastrointestinal complaint (9% versus 25% p < 0.05). Subjects who received buprenorphine were less likely to return to the same ED within 30 days for a drug-related visit (8%) compared to those who received symptomatic treatment (17%) (p < 0.05). Conclusions: Buprenorphine was a common treatment for OW in this ED without any documented adverse outcomes. Given that it did not result in an increase in drug-related return ED visits and its proven efficacy in other settings, a prospective evaluation of its potential value to ED patients who present with OW is warranted. © 2006 Elsevier Ireland Ltd. All rights reserved.
Nonclassical binding of formylated peptide in crystal structure of the MHC class lb molecule H2-M3

Abstract H2-M3 is a class Ib MHC molecule of the mouse with a 10 4 -fold preference for binding N-fonmylated peptides. To elucidate the basis of this unusual specificity, we expressed and crystallized a soluble form of M3 with a fonnylated nonamer peptide, fMYFINILTL, and determined the structure by X-ray crystallography. M3, refined at 2.1A˚resolution, resembles class la MHC molecules in its overall structure, but differs in the peptide-binding groove. The A pocket, which usually accommodates the free N-terminus of a bound peptide, is closed, and the peptide Is shifted one residue, such that the P1 side chain is lodged in the B pocket. The formyl group Is coordinated by His-9 and a bound water on the floor of the groove.
Communicating archaeology: Words to the wise

As archaeologists, we are often called upon to discuss our work with various groups that share our interest in human culture and human adaptation, to communicate with those whose heritage we study,...
Synthesis of tritium labelled (3R*, 5S*)‐3, 5‐dihydroxy‐9, 9‐diphenyl‐6, 8‐nonadienoate

Methyl (3R*, 5S*)-(E)-3,5-dihydroxy-9,9-diphenyl-6,8-nonadienoate (1) is a competitive inhibitor of HMG-CoA reductase, the rate-limiting step in cholesterol biosynthesis. We synthesized 1 with a tritium label at C3 in order to investigate tissue selectivity. The synthesis began with β-phenyl- cinnamaldehyde which was homologated to (E)-5,5-diphenyl-2,4-pentadienal in three steps. Addition of the dianion of methyl acetoacetate gave methyl (E)-5-hydroxy- 9,9-diphenyl-3-oxo-6,8-nonadienoate. Diastereoselective introduction of the tritium label was achieved using tritium labelled sodium borohydride, triethylborane and a catalytic amount of pivalic acid. The radiochemical yield for this step was 7.5 %, the specific activity was 13.3 mCi/mmole, and the product was >95% radiochemically pure. This method may be applicable to the preparation of other radiolabelled HMG-CoA reductase inhibitors which possess a 3,5-dihydroxy acid moiety.
Ocular volume measured by CT scans

Newer CT scans have greatly enhanced oculometric research and made it possible to measure ocular dimensions. With these measurements, ocular volume can be more accurately estimated to understand its relationship with age and sex. One hundred CT orbit scans with presumed normal eyes were used for the data base. The mean values and normal variations of ocular volumes at various ages in both sexes are presented. Rapid growth of the eyeball was noted during the first 24 months of age. It reached its peak between the ages of 18 and 30 years of age, after which there was a reduction. Results may be of help in recognizing eye abnormalities such as microophthalmus and macrophthalmia.
Design of a neural decoder by sensory prediction and error correction

Brain-machine interfaces (BMI) hold great potential to improve the quality of life of many patients with disabilities. The neural decoder, which expresses the mapping between the neural signals and the subject's motion, plays an important role in BMI systems. Conventional neural decoders are generally in the form of a kinematic Kalman filter which does not possess an explicit mechanism to deal with the unavoidable mismatch between the biological system and the model of the system used by the decoder. This paper presents a novel design of a neural decoder that uses a one-step model predictive controller to generate a control signal that compensates for the inherent model mismatch. The effectiveness of the proposed decoding algorithm compares favorably to the state-of-the-art Kalman filter in numerical simulations with different degrees of model mismatch.
Conformal conservation laws and geometric integration for damped Hamiltonian PDEs

Conformal conservation laws are defined and derived for a class of multi-symplectic equations with added dissipation. In particular, the conservation laws of energy and momentum are considered, along with those that arise from linear symmetries. Numerical methods that preserve these conformal conservation laws are presented in detail, providing a framework for proving a numerical method exactly preserves the dissipative properties considered. The conformal methods are compared analytically and numerically to standard conservative methods, which includes a thorough inspection of numerical solution behavior for linear equations. Damped Klein-Gordon and sine-Gordon equations, and a damped nonlinear Schrodinger equation, are used as examples to demonstrate the results.
Mechanism of inactivation of neuronal nitric oxide synthase by N(ω)-allyl-L-arginine

Nω-Allyl-l-arginine is shown to be a competitive reversible inhibitor and time-dependent inactivator of bovine brain nitric oxide synthase (nNOS). The enzyme is protected against inactivation by the presence of the substrate, the absence of O2, or if NADP+ is substituted for NADPH. The NADPH absorption spectrum is converted to that of NADP+ concomitant with inactivation. The latter two results indicate that redox chemistry is required for inactivation. Nω-Allyl-Nω-hydroxy-l-arginine is synthesized and shown also to be a competitive inhibitor and time-dependent inactivator of nNOS, suggesting that it is a viable intermediate in the inactivation process. Inactivation of nNOS with Nω-allyl-[14C]-l-arginine or Nω-[3H]allyl-l-arginine followed by gel filtration or dialysis results in no radioactivity bound to the enzyme. It is shown spectrophotometrically as well as by HPLC that the heme is modified to four different species during inactivation. Inductively coupled plasma atomic emission spectrophotometry is u...
Academic medical libraries' policies and procedures for notifying library users of retracted scientific publications.

Abstract Academic medical libraries have a responsibility to inform library users regarding retracted publications. Many have created policies and procedures that identify flawed journal articles. A questionnaire was sent to the 129 academic medical libraries in the United States and Canada to find out how many had policies and procedures for identifying retracted publications. Of the returned questionnaires, 59% had no policy and no practice for calling the attention of the library user to retracted publications. Forty-one percent of the libraries called attention to retractions with or without a formal policy for doing so. Several responding libraries included their policy statement with the survey. The increasing number of academic medical libraries that realize the importance of having policies and practices in place highlights the necessity for this procedure.
Oribatid mite predation by small ants of the genus Pheidole

Using “cafeteria experiments” with forest soil and litter, I obtained evidence that at least some small Neotropical species of Pheidole prey on a wide array of slow-moving invertebrates, favoring those of approximately their own size. The most frequent prey were oribatid mites, a disproportion evidently due in part to the abundance of these organisms. The ants have no difficulty breaking through the calcified exoskeleton of the mites.
Neurosurgery in the decade of the brain. The 1990 AANS presidential address.

✓ The decade of the 1990's has provided neurosurgery with multiple challenges and opportunities. Numerous developments hold a promise for making the 1990's the most rewarding decade of the 20th century for neurosurgery. The “Decade of the Brain” resolution, adopted by the United States House and Senate and signed into law by President Bush in 1989, has provided the specialty with staggering opportunities. Neurosurgery and the basic and clinical neurosciences would be strengthened by the development of a major new philanthropic organization called the “American Brain Association” that would carry the activities of the Decade of the Brain into the 21st century. Major efforts are being made to improve organized neurosurgery's responsiveness to member needs. These include the strategic planning project undertaken by the Board of Directors of the American Association of Neurological Surgeons (AANS) and efforts to strengthen the Joint Council of State Neurosurgical Societies. The AANS has been extremely active ...
Modeling and Behavior of Steel Plate Connections Subject to Various Fire Scenarios

Shear connections are common connection types and they are designed to resist only shear loads. In a fire event, the axial restraint provided by adjacent structure creates unanticipated compressive and tensile forces in the beam and thus the connection. Using finite-element models, this study examines single-plate shear connections that are bolted to the beam and welded to the supporting girder. A floor subassembly, which includes the beam, girder, slab, and connection, is modeled so that appropriate forces are applied to the connection. The model is validated with the experiments of bolted lap splice plates at elevated temperatures, as well as full-scale experiments. This paper (1) illustrates efficient modeling methods for these floor subassemblies; (2) evaluates the importance of the slab in the connection response; and (3) examines the effects of the rate of heating and cooling on the connection. The results show that care needs to be taken as to how the concrete slab is represented in the model. The heating and cooling rates affect the beam stress distribution, peak temperatures, and peak displacements, but not the peak beam axial force. Also, the cooling phase creates large tensile forces in the connection which can lead to failure.
The surgical treatment of pancreatic disease.

Periampullary carcinoma and chronic pancreatitis are the most frequent indications for operations on the pancreas. Exploration and resection by pancreaticoduodenectomy is the preferred method of treatment for carcinoma of the periampullary region when the malignancy is localized to this area and when it does not invade the superior mesenteric vein. A direct anastomosis of the remaining pancreatic duct to the side of the jejunum is performed when possible. Total pancreatectomy has been utilized for extensive carcinomas of the pancreas and for early lesions with an essentially normal pancreatic parenchyma to avoid the hazards of the pancreaticojejunal anastomosis. Chronic pancreatitis has been treated by various operative procedures. Duct stenosis and calculi, fibrosis and inflammation, and occasional pseudocyst formation commonly occur in the head of the gland. This area seems to act as a site of origin and perpetuation of the disease process. Proximal pancreatic resection by pancreaticoduodenectomy is being performed more frequently with anastomosis of five to 15 per cent of the pancreatic tail to the jejunum. Diabetes may be prevented and some external pancreatic enzyme function may thereby be preserved. In any pancreaticoduodenectomy, preservation of the entire stomach and first portion of the duodenum and intact pylorus should be considered. Preliminary observations suggest that the presence of an intact stomach and a functioning pylorus tend to lessen the digestive disturbances following this resection. After total pancreatectomy, further efforts should be made to extract and regraft the patient's viable islet of Langerhans cells from the excised pancreas. A reliable method of restoring insulin production would extend the use of total pancreatectomy for both malignant and benign pancreatic disease.
Highlights from PHENIX II – Exploring the QCD medium

Much of the present experimental effort at RHIC is now directed towards understanding the properties of the hot and dense colored medium created in A+A collisions. Recent results from PHENIX on the dynamical evolution of the medium and its response to high momentum probes are presented, and their impact on our overall understanding of heavy-ion collisions is discussed.
Principles and applications of polymerase chain reaction: basic science for the practicing physician.

Objective To review the technology of polymerase chain reaction (PCR) and its use in diagnostic medicine and biomedical research. Data Sources A literature review was performed using the PubMed database for English-language articles published between January 1, 1985, and November 31, 2007, using the following keywords: polymerase chain reaction, real-time polymerase chain reaction , and applications of real-time polymerase chain reaction. Study Selection Select review articles and primary articles relevant to medical applications of PCR were chosen. Results As a revolutionary technique, PCR provides a rapid and accurate means of amplifying DNA. It has enabled the cloning and manipulation of genes for biomedical research and has facilitated the diagnosis of genetic, infectious, and oncologic diseases. The use of reverse transcriptases to evaluate RNA levels and the extension of PCR technology to quantify DNA amplification in real time has brought major advances to the application of PCR. By allowing the determination and quantification of changes in gene expression, these techniques have provided a greater understanding of disease processes and now serve as a foundation for diagnostics and basic science research. Conclusions Both PCR and real-time PCR have dramatically changed the field of basic science and diagnostic medicine. These technologies are now a well-established, indispensable part of research and clinical laboratories.
Limiting cross sections for multiphoton coupling

The availability of extraordinarily bright femtosecond ultraviolet sources is rapidly extending the study of nonlinear atomic responses into an unexplored regime involving intensities in the range of ∼10 20 W/cm 2 . An estimate is made, covering approximately ten orders of magnitude in intensity, of the effective cross section for nonlinear energy transfer to atoms undergoing subpicosecond irradiation. This treatment, which includes: (a) threshold measurements for low stages of ionization in the low intensity regime ( 10 19 W/cm 2 ), indicates that the cross section for energy transfer in the high intensity (>10 19 W/cm 2 ) high Z limit falls in a relatively narrow range between simply established upper and lower bounds. The values of these limits are σ m =8 πλ c 2 (upper) and the magnitude of the total photoabsorption cross section of Cf at the K edge (lower). Based on this analysis, the maximum cross section for heavy atoms in the high intensity limit is expected to be approximately max ∼10 −20 cm 2 , a value which represents an energy transfer rate of ∼1 W/atom for an assumed intensity of 10 20 W/cm 2 . Coupling of this strength would enable the creation of highly energetic and strongly nonequilibrium states of matter and motivates the conclusion that stimulated emission in the X-ray range can be Estimation de la section efficace effective du transfert d'energie non lineaire vers des atomes soumis a une irradiation subpicoseconde. (Mesures de seuil d'ionisation, determination experimentale pour le transfert total d'energie a intensite intermediaire de la section efficace moyenne, et estimations theoriques pour le regime en champ fort). Application a l'emission stimulee dans le domaine des rayons X
Spatial Sorting Algorithms for Parallel Computing in Networks

Many basic techniques in computer science have been founded on the assumption that physical computing resources are scarce but orderly, and that the cost of effective direct communication between physically distant parts of a computer system is affordable. In large scale cluster computing installations, fine-grained parallel computing hardware, or wireless mesh networks, these familiar assumptions may not hold. In this paper we present adaptations of two especially simple classic sequential sorting algorithms, namely bubble sort and insertion sort, to parallel execution in spatially constrained networks of devices, using particle systems and asynchronous automata graphs. In both cases we are able to get significant speed-ups of these na\"ive $O(n^2)$ algorithms, attaining linear time complexity or better given sufficient parallelism. For insertion sort, we obtain these results without depending on any but statistical properties the network medium. We discuss potential extensions of these physically and biologically inspired techniques to more complex parallel algorithms.
Induction of leaf senescence in Arabidopsis thaliana by long days through a light‐dosage effect

Given the influence of photoperiod on reproductive development and whole-plant senescence in monocarpic plants, one would suspect that leaf senescence in these plants might be under photoperiodic control. In Arabidopsis thaliana, which is monocarpic and also a nonobligate long-day (LD) plant, LDs (16 h, 300 μmol m−2 s−1) caused leaves to die earlier than did short days (SDs, 10 h). Since leaf longevity was not paralleled by the reproductive development in the present study, the reproductive structures did not seem to be the primary controls of leaf senescence. The LD effect appeared to depend on the amount of light rather than on day length, for leaves given LDs at reduced light intensity (180 μmol m−2 s−1) lived longer than those in LDs with full light. In addition, the higher light intensity promoted chlorophyll loss and anthocyanin accumulation in LDs. Thus, senescence of these leaves seems to be governed by light dosage rather than photoperiod. Light may play a natural role in promoting the senescence of A. thaliana leaves.
The Importance of Student Models in Intelligent Tutoring for Complex-Dynamic Systems

Many computer-based training systems present instruction linearly, with exactly one path through the system that each student must follow. Students have little control over the pace, content branching, or flow of instruction. Student modeling within intelligent tutoring systems addresses these issues by interpreting student behaviors, representing the student's knowledge, and providing personalized instructional content. However, there is disagreement over the necessary content and structure of student models and their general utility. This paper discusses the development of an intelligent tutoring architecture with two instantiations that use sophisticated student models. Similar tutors with scaled-down student models will be used to evaluate the effectiveness of the differing student modeling approaches.
Constraining a numerical geodynamo model with 100 years of surface observations

SUMMARY To constrain numerical geodynamo models with surface geomagnetic observations, we develop an assimilation scheme for mapping surface geomagnetic data into numerical dynamo solutions. This approach is similar to the optimal interpolation that has been used in atmospheric data assimilation for many years. The scheme is numerically stable and computationally efficient, and has been tested in a series of observing system simulation experiments with either simplified MHD systems or synthetic data from numerical dynamo simulations. In this study, the algorithm is integrated with our MoSST core dynamics model and is tested with 100-yr surface geomagnetic observations, starting in 1900. These experiments use 5 and 20-yr analysis intervals, and forecasts are made every 5 yr starting from 1905. We show that forecast errors gradually reduce over the course of the assimilation. Shorter assimilation runs (starting in 1960 and 1980) result in much larger forecast errors. We investigate the causes of the error reduction by examining how the assimilation impacts the unobserved variables. We discuss the implications for the ability of much longer assimilation runs to constrain the physical fields within the Earth's outer core.
Hayek, Liberalism and Social Knowledge

The Nobel prizewinner F. A. Hayek has spent his long career defending classical liberalism and the free market from those wishing to introduce planning and greater “rationality” into social life. As this study tries to show, Hayek's defence of market liberalism is predicated on his theory of social knowledge and how liberal principles and processes are best suited to cope with our limited ability to utilize this knowledge. He argues that we can cope best with our ignorance by resisting the temptations to set up centralized decision-making mechanisms and by accepting the discovery procedure of the market mechanism. Unlike other attempts to defend classical liberalism, Hayek offers a radically new knowledge-based foundation. If Marx's work could be labelled an economically-based sociology, Hayek's work could be labelled an epistemologically-based politics. But is his epistemological defence simply an ideological move to defend against attacks levelled at capitalism, or has he provided an indisputable foundation to justify the maintenance of liberal orders?
Role of iPLA2 in the regulation of Src trafficking and microglia chemotaxis

Microglia are immune effector cells in the CNS and their activation, migration, and proliferation play crucial roles in brain injuries and diseases. We examined the role of iPLA2 in the regulation of microglia chemotaxis toward ADP. Inhibition of iPLA2 by BEL or iPLA2 knock-down exerted a significant inhibition on PI3K activation and chemotaxis. Further examination revealed that iPLA2 knock-down abrogated Src activation which is required for PI3K activation and chemotaxis. Colocalization studies demonstrated that cSrc-GFP was retained in the endosomal recycling compartment (ERC) in iPLA2 knock-down cells, but addition of arachidonic acid (AA) could restore cSrc trafficking to the plasma membrane by allowing the formation/release of recycling endosomes associated with cSrc-GFP. Using BODIPY-AA, we showed that AA is selectively enriched in recycling endosomes. These results suggest that AA is required for the cSrc trafficking to the plasma membrane by controlling the formation/release of recycling endosomes from the ERC.
A Manto Carlo Technique for Solving Eddy Current Problems

With the recent progress in the parallel processing technology, there comes the need to reinvestigate various techniques employed in computational electromagnetics. The Monte Carlo technique discussed is one alternative that has the attractive feature of requiring very little set up time. Because no grid or volume discretization is involved, a smaller demand on storage capacity is required. The approach proposed in based on the random walk idea of a particle saying about in a medium, and registering information upon contact with a boundary. The standard Helmholtz type equation encountered in eddy current problem in solved by lotting one particle become multiple particles in its walk through the problem. Application to a simple 2-D eddy current problem is presented. The results indicate that on a data parallel system such as Maspar MP-1, the Monte Carlo method become competitive as a total solution approach for problems involving more than 400 unknowns.
Toxic effects of PCB126 and TCDD on shortnose sturgeon and Atlantic sturgeon.

Exposure to chemical contaminants is often invoked to explain recruitment failures to populations of sturgeon worldwide, but there is little empirical evidence to support the idea that young sturgeon are sensitive at environmentally relevant concentrations. The authors used shortnose sturgeon (Acipenser brevirostum) and Atlantic sturgeon (Acipenser oxyrinchus) as models to investigate the sensitivities of sturgeon to early-life-stage toxicities from embryonic exposures to graded doses of polychlorinated biphenyl 126 (PCB126) and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Survival to hatching of shortnose sturgeon decreased with increasing dose, although the duration of the embryonic period was not significantly altered by exposure in either species. Morphometric features of larvae of both species were affected by dose, including shortening of the body, reduction in head size, reduction in quantity of yolk reserves, and reduction in eye size. Eye development in both species was delayed with increasing dose for both chemicals. The persistence of larvae in a food-free environment decreased inversely with dose in both species, with sharp declines occurring at PCB126 and TCDD doses of ≥1 ppb and ≥0.1 ppb, respectively. Dose-responsive early-life-stage toxicities reported here are among the more sensitive found in fish and occurred at burdens similar to those found in situ in a sympatric bottom-dwelling bony fish in the Hudson River Estuary. The present study is among the first demonstrating the sensitivity of any sturgeon to the hallmark early-life-stage toxicities induced by aryl hydrocarbon receptor agonists. Environ. Toxicol. Chem. 2012; 31: 2324–2337. © 2012 SETAC
Whole genome profiling of spontaneous and chemically induced mutations in Toxoplasma gondii

Next generation sequencing is helping to overcome limitations in organisms less accessible to classical or reverse genetic methods by facilitating whole genome mutational analysis studies. One traditionally intractable group, the Apicomplexa, contains several important pathogenic protozoan parasites, including the Plasmodium species that cause malaria. Here we apply whole genome analysis methods to the relatively accessible model apicomplexan, Toxoplasma gondii, to optimize forward genetic methods for chemical mutagenesis using N-ethyl-N-nitrosourea (ENU) and ethylmethane sulfonate (EMS) at varying dosages. By comparing three different lab-strains we show that spontaneously generated mutations reflect genome composition, without nucleotide bias. However, the single nucleotide variations (SNVs) are not distributed randomly over the genome; most of these mutations reside either in non-coding sequence or are silent with respect to protein coding. This is in contrast to the random genomic distribution of mutations induced by chemical mutagenesis. Additionally, we report a genome wide transition vs transversion ratio (ti/tv) of 0.91 for spontaneous mutations in Toxoplasma, with a slightly higher rate of 1.20 and 1.06 for variants induced by ENU and EMS respectively. We also show that in the Toxoplasma system, surprisingly, both ENU and EMS have a proclivity for inducing mutations at A/T base pairs (78.6% and 69.6%, respectively). The number of SNVs between related laboratory strains is relatively low and managed by purifying selection away from changes to amino acid sequence. From an experimental mutagenesis point of view, both ENU (24.7%) and EMS (29.1%) are more likely to generate variation within exons than would naturally accumulate over time in culture (19.1%), demonstrating the utility of these approaches for yielding proportionally greater changes to the amino acid sequence. These results will not only direct the methods of future chemical mutagenesis in Toxoplasma, but also aid in designing forward genetic approaches in less accessible pathogenic protozoa as well.
A general computer aided tool to assess the impact of component value tolerance on power supply performance

A computer-based tool for checking the effects of component value variation within a specified tolerance range is discussed. A model-building process is described for handling the single nonlinear equation that describes the investigated system over one complete cycle. Perturbation and subsequent linearization of the equation are used to obtain a linear continuous system for an 'averaged' system model. This procedure is used for the analysis of a full-bridge converter circuit. >
A High Percentage of Beef Bull Pictures in Semen Catalogues Have Feet and Lower Legs that Are Not Visible

A total of 1379 beef bull pictures were surveyed to determine visibility of feet and legs from four American semen company websites. Five different breeds were represented: Angus, Red Angus, Hereford (polled and horned), Simmental, and Charolais. In addition to visibility, data on other variables were collected to establish frequencies and correlations. These included breed, color, material that obscured visibility, such as grass, picture taken at livestock show or outside, semen company, photographer, video, and age of bull. A foot and leg visibility score was given to each bull picture. Only 19.4% of the pictures had fully visible feet and legs. Both the hooves and dewclaws were hidden on 32.5% of the pictures. Correlation between bull's birthdate and the first four visibility scores was statistically significant (P < 0.0001). As age increased the feet and legs were more likely to be visible in the bull's picture. This may possibly be due to greater availability of both photo editing software and digital photography. One positive finding was that 6% of the bulls had a video of the bull walking which completely showed his feet and legs.
Seasonal modulations in the Eddy field of the South Pacific Ocean

Abstract Decade-long satellite altimeter data from the Ocean Topography Experiment (TOPEX)/Poseidon and European Remote Sensing Satellite-1 and-2 (ERS-1/2) missions are analyzed to investigate the eddy signals in the South Pacific Ocean. High–eddy kinetic energy (EKE) bands with well-defined annual cycles are detected along the eastward-flowing surface currents of the South Tropical Countercurrent (STCC) between 21°–29°S and the South Equatorial Countercurrent (SECC) centered near 9°S. Overriding the westward-flowing South Equatorial Current (SEC), the STCC layer has the sign of its mean potential vorticity gradient opposite to that in the SEC layer, subjecting the vertically sheared STCC–SEC system to baroclinic instability. In austral winter, the STCC–SEC system is baroclinically more unstable than in other seasons because of the large vertical shear and weak stratification. This seasonal variation in the intensity of baroclinic instability is responsible for the seasonal modulation of the STCC's EKE fi...
Generalized trigonometric identities and invariant imbedding

Abstract It is shown under weak hypotheses that systems of 2n linear differential equations in 2n variables generate sets of identities similar in structure to the classical trigonometric identities. For clarity of exposition only the case n = 1 is actually treated, but all final equations are written in such a manner as to be directly applicable to matrix systems (n > 1). These identities allow one to avoid, in a very simple way, certain difficulties which often occur in the integration of the Riccati equations arising from application of the invariant imbedding method to two point boundary value problems associated with such linear systems. The overall usefulness of the imbedding method is thereby considerably extended. One analytical and one numerical example are given to illustrate the actual use of these identities.
PAMMEGISCHIA AND TRICHOFOENUS DISCARDED (AULACOID HYMENOPTERA)

It is strange that such a distinct genus as Aulacus should not have been recognized by American workers, but there seems to be no doubt that our Pammegischia Provancher, 1883 is merely Aulacus Jurine, 1807.
Reasonable Expectations: Oral Proficiency Goals for Intermediate-Level Students of German.

This article reports a study gauging the average oral proficiency as measured by the American Council on the Teaching of Foreign Languages (ACTFL) Oral Proficiency Interview (OPI) of college students (N = 20) studying German at the end of their fourth semester. All OPIs were official ACTFL double-rated interviews. Proficiency, as measured by the OPI, ranged between Novice High and Intermediate Mid. Discussion centers on reasonable expectations for high school graduation and for college language requirements.
Global and serial neurons form A hierarchically arranged interface proposed to underlie memory and cognition

It is hypothesized that the cholinergic and monoaminergic neurons of the brain from a global network. What is meant by a global network is that these neurons operate as a unified whole, generating widespread patterns of activity in concert with particular electroencephalographic states, moods and cognitive gestalts. Apart from cholinergic and monoaminergic global systems, most other mammalian neurons relay sensory information about the external and internal milieu to serially ordered loci. These "serial" neurons are neurochemically distinct from global neurons and commonly use small molecule amino acid neurotransmitters such as glutamate or aspartate. Viewing the circuitry of the mammalian brain within the global-serial dichotomy leads to a number of novel interpretations and predictions. Global systems seem to be capable of transforming incoming sensory data into cognitive-related activity patterns. A comparative examination of global and serial systems anatomy, development and physiology reveals how global systems might turn sensation into mentation. An important step in this process is the permanent encoding of memory. Global neurons are particularly plastic, as are the neurons receiving global inputs. Global afferents appear to be capable of reorganizing synapses on recipient serial cells, thus leading to enhanced responding to a signal, in a particular context and state of arousal.
Reproductive biology of a filter-feeding amphipod, Leptocheirus pinguis , with extended parental care

Leptocheirus pinguis (Stimpson, 1853) is a widely distributed, abundant, endobenthic amphipod that engages in extended parental care, i.e. females host their juveniles in their burrows for extended time periods. I examined reproduction and population biology of L. pinguis at mean low water (MLW) in muddy sediment in Lowes Cove, Maine, USA. Cores around individual burrows were taken monthly in 1994 and 1995, and four seasonal samples were taken at different tidal heights. During the major reproductive periods in spring/early summer and in the fall, females produced several consecutive broods and hosted growing offspring in their burrows. Juveniles remained in their mothers' burrows until they reached a length of 5 mm (approximately one-third adult size) or more. At the study site, the majority of amphipods in individual burrows were adult females. Following the main reproductive periods, subadult individuals were found in their own burrows, but densities did not increase following the reproductive period in spring/early summer 1994, probably because large numbers of L. pinguis emigrated via the water column between June and December. L. pinguis is an annual species. Many members of the cohort born in spring/early summer start reproducing in the fall, and survive until the following spring when they produce several broods. Members of the cohort born in the fall start reproducing the following spring and also produce several consecutive broods. Both the spring/early summer and fall cohorts die off after the major reproductive period in the following spring/early summer. High standing stocks of microphytobenthos occur in soft-bottoms at MLW, and I conclude that L. pinguis can engage in extended parental care there because its food is abundant year-round. The limited expandability and low stability of burrows in soft-bottoms at MLW do not permit long persistence of parent–offspring groups in L.␣pinguis.
Diagnosis of subarachnoid hemorrhage: are we doing better?

See related article, pages 1216–1221. When I began practicing emergency medicine 25 years ago, a stroke patient’s arrival to the emergency department (ED) did not elicit the frenetic burst of activity that it currently does. For that matter, neither did the arrival of a heart attack patient—until the approval of thrombolytic treatment for myocardial infarction. For patients with cerebrovascular emergencies, new treatment options such as thrombolytics and pro-coagulants demand earlier and accurate diagnosis. The shift to early aneurysm obliteration for aneurysmal subarachnoid hemorrhage (SAH) makes its early and accurate diagnosis equally important. Forty percent of patients with SAH die, and 30% of survivors are left with significant neurological disability1; however, nearly half of all patients present in good clinical condition.2 In this group, early treatment prevents rebleeding and results in excellent outcomes. Unfortunately, numerous investigations over several continents and decades document that physicians miss the diagnosis of SAH with a disappointing frequency.3–10 In this issue of Stroke ,11 Vermeulen and Schull present data suggesting that Canadian emergency physicians miss the diagnosis of SAH in 5.4% of cases. Although this may seem like a high miss rate, it is much lower than what has been previously reported. A 2000 review of the subject showed that SAH was misdiagnosed in 32% of 685 cases pooled from 4 large studies.12 The average time delay was 6 days. Most misdiagnosed patients present in good clinical condition but their condition often deteriorates by the time of the second visit. Analysis suggests 3 recurring, largely preventable errors are responsible for physician misdiagnosis: lack of awareness of the spectrum of presentation of SAH, failure to perform (and understand the limitations of) computed tomographic imaging (CT scan), and failure to …
Differential Microstrip and Slot-Ring Antennas for Millimeter-Wave Silicon Systems

Differential on-chip microstrip and slot-ring antennas with a quartz superstrate are presented for wafer-scale silicon systems. The antennas are fed at the nonradiating edge, which is compatible with differential coupled-lines, and are built on a 0.13-μ m CMOS process with a layout that meets all the metal density rules. A high radiation efficiency is achieved using a 100- μm quartz superstrate placed on top of the silicon chip. Both antennas have a measured gain varies from about 2 to 3 dBi at 91-94 GHz, with a - 10-dB S11 bandwidth of 7-8 GHz and a simulated radiation efficiency of >;50%. The designs are compatible with single- and multielement transceivers, and with wafer-scale imaging systems and power-combining arrays.
Coupled mode analysis and demonstration of an electrooptic frequency shifter

We present a semiclassical wave mixing analysis to study the effect of a microwave field on a train of short optical pulses in a traveling wave modulator structure. The devices can achieve long range and continuous shifting. Experimental results from such device will be shown.
A parallel implementation of the discrete wavelet transform

For signal and image analysis, the wavelet transform possesses the ability to extract details from the signal or image. Higher frequency components are extracted using finer time resolution, and lower frequency components are extracted using coarser time resolution. The transform decomposes a scanned signal into localized contributions for multiscale analysis. The authors present a general multiprocessor architecture for the efficient computation of signal decomposition with general wavelet bases. Their discrete wavelet transform (DWT) architecture is composed of a linear array of commercially available processors, which is easily reconfigurable for variable sized windows of data to be transformed. The use of commercially available processors replaces the costly special-purpose VLSI chip, and can be reprogrammed for other digital signal processing applications. Combining the filtering and decimation processes in the decomposition stage via a block state-space formulation achieves an efficient real-time implementation. >
Three-dimensional nanopillar-array photovoltaics on low-cost and flexible substrates

Solar energy represents one of the most abundant and yet least harvested sources of renewable energy. In recent years, tremendous progress has been made in developing photovoltaics that can be potentially mass deployed. Of particular interest to cost-effective solar cells is to use novel device structures and materials processing for enabling acceptable efficiencies. In this regard, here, we report the direct growth of highly regular, single-crystalline nanopillar arrays of optically active semiconductors on aluminium substrates that are then configured as solar-cell modules. As an example, we demonstrate a photovoltaic structure that incorporates three-dimensional, single-crystalline n-CdS nanopillars, embedded in polycrystalline thin films of p-CdTe, to enable high absorption of light and efficient collection of the carriers. Through experiments and modelling, we demonstrate the potency of this approach for enabling highly versatile solar modules on both rigid and flexible substrates with enhanced carrier collection efficiency arising from the geometric configuration of the nanopillars.
Venous thromboembolism in African-Americans: A literature-based commentary

Among the cardiovascular diseases and after ischemic heart disease and stroke, venous thromboembolism (VTE) is the third leading cause of death in the U.S. (3). Although VTE is seen across most ethnic groups in the U.S. as well as throughout the world, the rate varies. In the U.S., American Indians/Alaskan Natives as well as Asians have been reported to have a significantly lower rate of deep vein thrombosis (DVT) and pulmonary embolism (PE) as compared to blacks and whites. In sharp conrast blacks appear to have much higher rates than whites. Although these rate differences are thought in part by some to be attributable to disparities in diagnosis and care as well as genetics, it nevertheless is important to define as well as to understand the true incidence and impact so that both public health and clinical resources can be maximally utilized. The purpose of this commentary is to review the VTE burden in the U.S. with respect to ethnicity in terms of clinical demographics and genetics with particular emphasis on blacks.
Whistleblowing And External Auditors

New federal legislation now makes it mandatory for auditors to disclose observed mis-conduct to outside agencies. This article examines this legislation and presents data from a national sample of 353 auditors to explore the level of support for these new regulations. The vast majority of auditors are found to oppose the legislation, but there are also major differences in opinion for different groups of auditors. The implications of these survey results are then discussed.