cssi/SciSciGPT-SciSciNet huggingface dataset:
Pediatric occult bacteremia

Pediatric occult bacteremia is a newly-recognized clinical condition. Less than two decades ago, bacteremia was considered insignificant unless it was associated with systemic symptoms. ’ Currently, occult bacteremia is a familiar clinical disease with potential complications, broadly defined as the presence of pathogenic bacteria in the blood of a child with either “trivial” illness (e.g., upper respiratory infection, otitis media, gastroenteritis) or no focus of infection whatever.2-6 These children are generally not ill-appearing and a large number are sent home after the initial visit.7s8 Clinical usage of the term bacteremia should distinguish it from septicemia, in which bacteria in the blood are associated with significant clinical manifestations of infection.9 The child who is a compromised host (i.e., with sickle cell anemia, splenectomized, immune deficient, etc.) is at greater risk of infection and subsequent complications than the patient with an intact immune system. ‘OJ ’ The clinician evaluating potentially ill children must triage these compromised patients into a separate category when considering the possibility of occult bacteremia.12
Proposed thermodynamic method to determine the vortex mass in layered superconductors

We describe a simple method to study vortex dynamics that can determine or set an upper limit on the vortex mass. The specific heat of the vortex lattice in layered superconductors has a classical limit of 1 kB per pancake vortex if the vortex mass is zero. If the vortex mass mv is finite, a new Einstein branch of normal modes will appear with a crossover temperature ΘE ∝ mv−1, and the specific heat will saturate at a new classical limit of 2 kB per pancake vortex.
A Rapid Gene Delivery-Based Mouse Model for Early-Stage Alzheimer Disease-Type Tauopathy

The perforant pathway projection from the entorhinal cortex (EC) to the hippocampal dentate gyrus is critically important for long-term memory and develops tau and amyloid pathologies and progressive degeneration starting in the early stages of Alzheimer disease (AD). However, perforant pathway function has not been assessed in experimental models of AD, and a therapeutic agent that protects its structure and function has not yet been identified. Therefore, we developed a new adeno-associated virus-based mouse model for perforant pathway tauopathy. Microinjection into the lateral EC of vectors designed to express either human tau bearing a pathogenic P301L mutation or enhanced green fluorescent protein as a control selectively drove transgene expression in lateral EC layer II perikarya and along the entire rostrocaudal extent of the lateral perforant pathway afferents and dentate terminal field. After human tau expression, hyperphosphorylated tau accumulated only within EC layer II perikarya, thereby modeling Braak stage I of transentorhinal AD tauopathy. Expression of pathologic human tau but not enhanced green fluorescent protein led to specific dose-dependent apoptotic death of perforant pathway neurons and loss of synapses in as little as 2 weeks. This novel adeno-associated virus-based method elicits rapid tauopathy and tau-mediated neurodegeneration localized to the mouse perforant pathway and represents a new experimental approach for studying tau-driven pathogenic processes and tau-based treatment strategies in a highly vulnerable neural circuit.
Assessing family preservation programs

Abstract The major existing evaluations of family preservation programs are reviewed and assessed. Although most of the evaluations used randomized experiments or close equivalents and were well carried out, the evaluations reviewed do not provide definitive findings concerning effectiveness. The evaluations were found to have the following shortcomings: 1) The numbers of subjects were too small to detect effects reliably, 2) The programs evaluated were not given enough time to be fully operational before being evaluated, 3) The major criterion of success, placement avoidance, is arguably insufficient, and 4) The analysis strategies used were overly simple. As a consequence, the evaluations neither support nor contradict the effectiveness of family preservation strategies
Polarization of light in shallow waters

Measurements of the upwelling polarized radiance in relatively shallow waters of varying depths and benthic conditions are compared to simulationsrevealing the depolarizing nature of the seafloor. Significant correlations between simulations and measurements are attained when the appropriate unpolarized, Lambertian bottoms are included in the radiative transfer model. The bottoms used in this study produce realistic upwelling radiance distributions as well as ranges of the degree of linear polarization (DoLP) that peak between 10 and 30%. This study specifically finds that polarization in upwelling radiance is best preserved at long wavelengths in clear waters and also at short wavelengths in phytoplankton- and CDOM-rich waters. These results can thus facilitate the detection of benthic materials as well as future studies of camouflage by benthic biota.The DoLPwas found to be highly sensitive to benthic reflectance, but the angle of polarization (AoLP), which quantifies the orientation of polarization, is independent of it. The AoLP could therefore be used to communicate and sense direction underwater.
Sites of alkylation of poly(U) by agents of varying carcinogenicity and stability of products.

Abstract Several alkylating agents of widely varying reported carcinogenicity (dimethylsulfate, diethylsulfate, ethylmethanesulfonate, methylnitrosourea, ethylnitrosourea and ethylnitrosoguanidine) were reacted with poly(U) at pH values ranging from 4.5 to 7.5. All nucleophilic centers (internal phosphate groups, ribose hydroxyls, and O 2 , N-3 and O 4 sites of the uracil base) were found reactive, though to different extents, at neutrality and in slightly acid solution. The distribution of products is a function of the alkylating agent and pH. The nitroso compounds are more reactive toward oxygens than are dialkylsulfates and alkylalkanesulfonates. The ratio of N : O alkyl products is strongly pH dependent, primarily due to the N-3 being most reactive at the higher pH values, while the diester is most reactive at the lower pH values. The extent of reaction of the O 2 , O 4 or 2′-O or ribose is not greatly affected over the pH range tested. At pH 5.0 alkyl ribophosphotriesters mainly lose alcohol to re-form a stable phosphodiester. With increasing OH − concentration, the favored reaction is chain scission at the 3′-O-P bond.
Cardiac arrhythmias in premature infants: An indication of autonomic immaturity?

Sinus arrhythmia was demonstrated in all of 30 healthy infants whose birth weights were less than 1,500 grams, and in 90 per cent of them there were also more marked arrhythmias. The severity and frequency of arrhythmias decreased as the weight and development of the infant increased.
Chromyl Chloride Chemistry on the TiO2(110) Surface

The surface chemistry of chromyl chloride (CrO2Cl2) on TiO2(110) was examined with TPD, AES, ΔΦ measurements, SSIMS, and XPS. CrO2Cl2 adsorbs on TiO2(110) at 130 K with a constant, coverage-independent sticking probability, which is presumably near unity based on TPD. ΔΦ data suggest the molecule is adsorbed with the oxygens bound to the surface and the chlorines pointing into vacuum. In TPD, multilayer CrO2Cl2 desorption occurs at 156 K, and monolayer desorption states occur at about 295 and 430 K. Approximately 0.09 ML (1 ML = 5.2 × 1014 sites/cm2) desorbs in each of the latter states. The remaining adsorbed CrO2Cl2 (0.48 ML) decomposes irreversibly above 500 K, eventually resulting in CrCl2 desorption above 700 K. No other decomposition products are observed in TPD. Adsorption of CrO2Cl2 at 585 K results in multilayer CrCl2 formation, while adsorption at or below 500 K results in a saturated monolayer. Between 500 and 700 K, XPS results suggest that the Cr deposited from CrO2Cl2 decomposition is reduce...
Software Configuration Management for JPL's Space Flight Operations Center Project

ABSTRACTConfiguration management (CM) is a discipline that is concerned with systematically controlling the configuration of a system at discrete points in time. CM is a management tool and requires constant communications. The challenge of applying our basic knowledge of CM to the development environment was nontrivial. This article relates lessons learned and suggestions for applying CM activities to software product development.
Active place recognition using image signatures

For reliable navigation, a mobile robot needs to be able to recognize where it is in the world. We previously described an efficient and effective image-based representation of perceptual information for place recognition. Each place is associated with a set of stored image signatures, each a matrix of numbers derived by evaluating some measurement functions over large blocks of pixels. One difficulty, though, is the large number of inherently ambiguous signatures which bloats the database and makes recognition more difficult. Furthermore, since small differences in orientation can produce very different images, reliable recognition requires many images. These problems can be ameliorated by using active methods to select the best signatures to use for the recognition. Two criteria for good images are distinctiveness (is the scene distinguishable from others?) and stability (how much do small viewpoint motions change image recognizability?). We formulate several heuristic distinctiveness metrics which are good predictors of real image distinctiveness. These functions are then used to direct the motion of the camera to find locally distinctive views for use in recognition. This method also produces some modicum of stability, since it uses a form of local optimization. We present the results of applying this method with a camera mounted on a pan-tilt platform.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Propagation of muon induced Cherenkov photons through a diffusive medium

Abstract Analytic functions are derived that describe the arrival time distribution of photons (photoelectrons) induced by the passage of a high energy muon through a detector containing a Cherenkov medium that has scattering and absorptive properties. These functions, derived in the diffusive approximation, are as yet the best analytic descriptions of photon propagation from a moving point source of photons. As such, usage of these functions within the context of likelihood or other reconstruction algorithms will increase the pointing accuracy of neutrino telescopes that are embedded in ice or submerged in water.
Limit Load Analysis of Cylindrical Vessels Under Internal Pressure and Axial Strain

Strain-based design is a newer technology used in safety design and integrity management of oil and gas pipelines. In a traditional stress-based design, the axial stress is relatively small compared to the hoop stress generated by internal pressure in a line pipe, and the limit state in the pipeline is usually load-controlled. In a strain-based design, however, axial strain can be large and the load-carrying capacity of pipelines could be reduced significantly below an allowed operating pressure, where the limit state is controlled by an axial strain. In this case, the limit load analysis is of great importance. The present paper confirms that the stress, strain and load-carrying capacity of a thin-walled cylindrical pressure vessel with an axial force are equivalent those of a long pressurized pipeline with an axial tensile strain. Elastic stresses and strains in a pressure vessel are then investigated, and the limit stress, limit strain and limit pressure are obtained in terms of the classical Tresca criterion, von Mises criteria, and a newly proposed average shear stress yield criterion. The results of limit load solutions are analyzed and validated using typical experimental data at plastic yield.Copyright © 2011 by ASME
Periodicity of Eclosion and Pre-Mating Behavior of Gypsy Moth

The eclosion and pre-mating behavior of 288 male and 450 female gypsy moth, Lymantria dispar (L.), adults were observed during July 22–29, 1972. Eclosion activity of both sexes was strictly diurnal; initial daily eclosion was synchronized with sunrise. The periodicity of peak eclosion differed from day to day, and appeared to be influenced by temperature variation; temperatures above 24°C apparently enhanced eclosion. The avg time from eclosion to first flight in males was 3.56±0.12 h. Nocturnal flight occurred at temperatures above 21°C.
INTRINSIC-FACTOR ANTIBODY IN THE SALIVA OF A PATIENT WITH PERNICIOUS ANÆMIA

Abstract PRECIPITABLE antibody to intrinsic factor has been found in the saliva of a patient with pernicious anaemia. This antibody was identified by use of ammonium-sulphate precipitation and a complex of 57 Co-labelled vitamin B 12 and intrinsic factor. A radioactive coprecipitation test demonstrated that this antibody was IgA. The antibody may neutralise intrinsic-factor activity and thereby accelerate vitamin-B 12 deficiency.
Botulinum A Toxin/Dimethyl Sulfoxide Bladder Instillations for Women With Refractory Idiopathic Detrusor Overactivity: A Phase 1/2 Study

We completed a phase 1/2 trial to evaluate the safety and potential efficacy of direct intravesical instillation of a botulinum type A toxin/dimethyl sulfoxide (DMSO) solution for treatment of idiopathic detrusor overactivity in women. Twenty-five women with medication-resistant, urodynamic-confirmed idiopathic detrusor overactivity were enrolled. A total of 9 patients were treated in phase 1 of the study. Three patients were given a 66% dosing of solution; 22 patients received the full 300 units of botulinum toxin and 50 mL of DMSO (50% concentration). Adverse effects, 24-hour pad weights, episodes of incontinence, postvoid residuals, and scores on the Blaivas-Groutz anti-incontinence scale, Indevus Urgency Severity Scale, Incontinence Impact Questionnaire-short form, and Urogenital Distress Inventory (6 items) questionnaire were recorded at baseline, 1 month, and 3 months after instillation. No serious adverse effects or clinically important increases in postvoid residual occurred. Among the 21 women who completed phase 2 of the study, the median number of incontinent episodes decreased from 4 at baseline to 2 at 1 month ( P =.004) and increased to 4 at 3 months ( P =.81). Median scores improved from baseline to 1 month on the Incontinence Impact Questionnaire (from 13 to 7; P =.007) and Urogenital Distress Inventory (from 10 to 5; P =.003). Although 11 women (52%) reported severe urgency based on the Indevus Urgency Severity Scale at baseline, only 1 (5%; P P =.004) women reported severe scores at 1 and 3 months, respectively. Direct instillation of botulinum toxin/DMSO solution is safe. Its promising clinical effect warrants further evaluation in a randomized, placebo-controlled phase 3 setting.
Abstract IA15: Context-specific oncogenesis by ETS-family transcription factors

Abstract Recurrent translocation involving ETS-family transcription factors including ERG and ETV1, ETV4, and ETV5 occur in over half of prostate cancers, implicating them as driver oncogenes in prostate tumorigenesis. Two observations pose important questions. 1) The same ETS factors aberrantly expressed in prostate cancer can be endogenously highly expressed in other tissues to modulate normal physiology (e.g., ERG expression in endothelial cells and ETV1 expression in neurons). 2) Forced overexpression in prostate model systems such as immortalized human primary prostate epithelial cells and mouse prostate yields minimal phenotype. These observations indicate that ETS mediated oncogenesis is highly dependent on the cellular context, which is mediated by the cell/tissue type and cooperating lesions. We asked how cellular context affects the DNA binding, transcriptional output, and phenotype of ETS proteins. We compared human ETS dependent tumor cell lines from two lineages, prostate cancer and gastrointestinal stromal tumor and show that ETS binding is largely tissue specific. Further, we have generated genetically engineered mouse models that express ETS in different tissues, within different compartments of the prostate gland, and with different cooperating lesions. We show that ERG binding to genomic DNA is largely similar in PTEN intact and PTEN null mouse prostates. Yet, ERG can only mediate a transcriptional program that mediates an aggressive phenotype in PTEN null prostates. These data suggests that cellular context is critical for ETS transcription factor function. Citation Format: Yu Chen, Shipra Shukla, Ping Chi, Brett Carver, Charles L. Sawyers. Context-specific oncogenesis by ETS-family transcription factors [abstract]. In: Proceedings of the AACR Special Conference on Advances in Prostate Cancer Research; 2012 Feb 6-9; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2012;72(4 Suppl):Abstract nr IA15.
Effects of Season and Scale on Response of Elk and Mule Deer to Habitat Manipulation

Abstract Manipulation of forest habitat via mechanical thinning or prescribed fire has become increasingly common across western North America. Nevertheless, empirical research on effects of those activities on wildlife is limited, although prescribed fire in particular often is assumed to benefit large herbivores. We evaluated effects of season and spatial scale on response of Rocky Mountain elk (Cervus elaphus) and mule deer (Odocoileus hemionus) to experimental habitat manipulation at the Starkey Experimental Forest and Range in northeastern Oregon, USA. From 2001 to 2003, 26 densely stocked stands of true fir (Abies spp.) and Douglas-fir (Pseudotsuga menziesii) were thinned and burned whereas 27 similar stands were left untreated to serve as experimental controls. We used location data for elk and mule deer collected during spring (1 Apr–14 Jun) and summer (15 Jun–31 Aug) of 1999–2006 to compare use of treated and untreated stands and to model effects of environmental covariates on use of treated stan...
Glycan microarray analysis of Candida glabrata adhesin ligand specificity

The Candida glabrata genome encodes at least 23 members of the EPA (epithelial adhesin) family responsible for mediating adherence to host cells. To better understand the mechanism by which the Epa proteins contribute to pathogenesis, we have used glycan microarray analysis to characterize their carbohydrate-binding specificities. Using Saccharomyces cerevisiae strains surface-expressing the N-terminal ligand-binding domain of the Epa proteins, we found that the three Epa family members functionally identified as adhesins in Candida glabrata (Epa1, Epa6 and Epa7) bind to ligands containing a terminal galactose residue. However, the specificity of the three proteins for glycans within this class varies, with Epa6 having a broader specificity range than Epa1 or Epa7. This result is intriguing given the close homology between Epa6 and Epa7, which are 92% identical at the amino acid level. We have mapped a five-amino-acid region within the N-terminal ligand-binding domain that accounts for the difference in specificity of Epa6 and Epa7 and show that these residues contribute to adherence to both epithelial and endothelial cell lines in vitro.
Modulation of murine allergic rhinosinusitis by CpG oligodeoxynucleotides.

Background Allergic rhinosinusitis is characterized by eosinophilic inflammation of the upper airway, which is induced by TH-2 cytokines. CpG oligodeoxynucleotides (ODN) are known to induce TH-1 and to suppress TH-2 cytokines in a variety of settings, including murine models of asthma. Objective To examine the effect of CpG ODN in a murine model of upper airway allergic inflammation and to correlate with reduction of its manifestations of sneezing and nasal scratching. Methods BALB/c mice were sensitized using Ovalbumin (Ova) intraperitoneally and challenged with aerosolized Ova. CpG ODN were administered at the time of Ova sensitization. Outcomes measured included nasal symptoms, submucosal eosinophilia in the areas lined by respiratory or olfactory epithelium, and bone marrow eosinophilia. To delineate the mechanism of CpG ODN-induced suppression of eosinophilic inflammation, in vitro experiments were carried out to examine the effect of stimulation with Ova on splenocytes obtained from mice that were treated with CpG or control ODN (or no ODN) in vivo. Supernatant was collected after 72 hours of incubation and cytokines were measured by enzyme linked immunosorbent assay. Results CpG ODN administered at the time of Ova sensitization effectively abrogated nasal symptoms and eosinophilic upper airway inflammation compared with mice treated with control ODN or with no ODN. Cytokine data revealed that Ova sensitization suppressed IFN-γ and induced IL-4 and IL-5 compared with non-sensitized mice. CpG ODN treatment reversed these effects. Conclusion CpG ODN prevents the development of TH-2-mediated eosinophilic inflammation and symptoms in a murine model of allergic rhinosinusitis.
Beak Trimming Effects on Beak Length and Feed Usage for Growth and Egg Production

Two experiments were conducted to compare beak treatment effects on pullets of three genetic stocks. Within each stock, equal numbers were assigned to three treatments: no beak trimming (IN), beak trimming once (1X), and beak trimming twice (2X). Beak treatment, genetic stock, and age effects along with interactions among main effects were examined for production-associated traits during rearing and brief periods of early egg production. Beaks of 1X and 2X pullets remained shorter than those of IN pullets through final measurements at 36 and 32 wk of age in Experiments 1 and 2, respectively. However, differences in beak length decreased as age increased. Upper beaks of 2X pullets remained shorter than those of 1X pullets, but lower beaks of 1X and 2X pullets did not differ by 20 wk in Experiment 2. Weight gains, feed usage, and efficiency of growth were affected by beak treatments. Beak trimming reduced gains, feed eaten, feed wasted, and total feed used, and 2X pullets used their feed more efficiently for weight gain and egg production. A general decrease occurred in differences among beak treatments for weight gains, feed eaten, feed wasted, and efficiency of gains with increasing age during rearing. Nevertheless, significant differences in feed consumed, feed wasted, and efficiency of feed used for egg production indicated an economic advantage in favor of beak trimming.
On the L ∞ -norm of extreme points for crossing supermodular directed network LPs

We discuss extensions of Jain’s framework for network design [8] that go beyond undirected graphs. The main problem is approximating a minimum cost set of directed edges that covers a crossing supermodular function. We show that iterated rounding gives a factor 3 approximation, where factor 4 was previously known and factor 2 was conjectured. Our bound is tight for the simplest interpretation of iterated rounding. We also show that (the simplest version of) iterated rounding has unbounded approximation ratio when the problem is extended to mixed graphs.
Capital, technology, and specialization in the neoclassical model

Abstract The paper studies the effects of technology and capital stock on trade using simulation. For this purpose, the paper develops and evaluates a model that is distinguished by its use of the Eaton–Kortum framework to explain intra-industry trade instead of the usual Armington assumption. It is found that the magnitudes and in many cases signs of the effects of capital stock and technology on specialization are very country-specific. This implies that the regression studies that estimate cross-country average effects have limited value. Looking at the volume of trade, the paper finds that capital endowments and industry-level comparative advantages have little effect on the volume of trade — the reduced inter-industry trade between more similar countries is compensated by increased intra-industry trade. Producer heterogeneity, on the other hand, has a significant effect on the volume of trade. The paper evaluates the accuracy of the model's forecasts by performing historical simulations for 1975–95, with the results showing that the model's predictions are accurate.
Rapid Construction of Adenoviral Vectors by Lambda Phage Genetics

Continued improvements of adenoviral vectors require the investigation of novel genome configurations. Since adenovirus can be generated directly by transfecting packaging cell lines with viral genomes isolated from plasmid DNA, it is possible to separate genome construction from virus production. In this way failure to generate a virus is not associated with an inability to generate the desired genome. We have developed a novel lambda-based system that allows rapid modification of the viral genome by double homologous recombination in Escherichia coli. The recombination reaction and newly generated genome may reside in a recombination-deficient bacterial host for enhanced plasmid stability. Furthermore, the process is independent of any restriction endonucleases. The strategy relies on four main steps: (i) homologous recombination between an adenovirus cosmid and a donor plasmid (the donor plasmid carries the desired modification[s] and flanking regions of homology to direct its recombination into the viral genome); (ii) in vivo packaging of the recombinant adenoviral cosmids during a productive lambda infection; (iii) transducing a recombination-deficient E. coli lambda lysogen with the generated lysate (the lysogen inhibits the helper phage used to package the recombinant andenoviral cosmid from productively infecting and destroying the host bacteria); (iv) effectively selecting for the desired double-recombinant cosmid. Approximately 10,000 double-recombinant cosmids are recovered per reaction with essentially all of them being the correct double-recombinant molecule. This system was used to generate quickly and efficiently adenoviral genomes deficient in the E1/E3 and E1/E3/E4 regions. The basis of this technology allows any region of the viral genome to be readily modified for investigation of novel configurations.
The Slow Pace of Rapid Technological Change: Gradualism and Punctuation in Technological Change

Discussions of technological change have offered sharply contrasting perspectives of technological change as gradual or incremental and the image of technological change as being rapid, even discontinuous. These alternative perspectives are bridged using the punctuated equilibrium framework of evolutionary biology. Using this framework, it is argued that the critical event is not a transformation of the technology, but speciation—the application of existing technology to a new domain of application. As a result of the distinct selection criteria and the degree of resource abundance in the new domain, a new technological form may emerge. The new technological form may be able to penetrate other niches and, in particular, may precipitate a process of 'creative destruction' and out-compete prior technologies. This framework is applied to an historical study of wireless communication from the early experimental efforts of Hertz to the modern development of wireless telephony.
RF capture studies for injection into a synchrotron

The capture process for a rapid cycling proton synchrotron is studied by numerical simulation. The RF programming is optimized to allow efficient capture such that minimum particle losses and reasonable capture voltage are attained. The total capture time is constrained to be less than 700 /spl mu/seconds. Two methods of trapping the injected beam by the synchrotron RF system are examined: by stationary adiabatic capture and by synchronous injection in a standing bucket of the ring. In the adiabatic method, the nonlinear function of Lilliequist and Symon(1959) is employed. The simulation allows the "tracking back" of the original distribution of any set of particles, in particular of those not captured at a given time, which is useful in studying injection alternatives such as shaping the phase-space density prior to injection. The simulation results will be used to design a chopper system to facilitate loss-free injection. >
Studies in Postural Control Systems Part I: Torque Disturbance Input

The postural control system in normal humans is studied by applying a mechanical torque disturbance to the system. It is shown that the response of the system can be approximated by a second-order differential equation where the parameters depend on the state of the system.
Propranolol: pooled Michaelis-Menten parameters and the effect of input rate on bioavailability.

Average steady-state propranolol plasma concentration (Css) were calculated from published steady-state propranolol clearance data for dose rates (R0) of 40, 80,160, 240, and 320 mg/day in divided doses every 6 hours. The Css-R0 data for each of four subjects were fit essentially perfectly by the equation: Css = KSSR0/ (Vm — R0). Very similar Vm and Km values were obtained with the Vmi and Kmi values for four parallel Michaelis-Menten pathways of propranolol metabolism. It is shown by use of the mean Vm and Km values that the propranolol input rate profoundly affects its bioavailability, which is expected for a first-pass drug that follows Michaelis-Menten elimination kinetics after oral dosing. This most likely explains the poor bioavailability of propranolol after a sustained-release formulation. The decreased bioavailability of propranolol when the number of subdivisions of the daily dose is increased is also explained. Clinical Pharmacology and Therapeutics (1985) 37, 481–487; doi:10.1038/clpt.1985.76
Modelling techniques for tutoring systems

Abstract An intelligent tutoring system (ITS) must incorporate models not only of knowledge of the real world and knowledge possessed by the learner but also of the relationship between the teacher and the learner. The role of the ITS is to coordinate a conversation between knowledge bases in both tutor and learner, simulating Socratic dialogue rather than rote learning and mechanical testing. Tutor and learner may take different perspectives but must come to agree that they share the same understanding. Modelling techniques used in ITS must be both grounded in theory and empirically validated if the ITS is to be successful. Our rationale is found in Conversation Theory. We discuss theories which provide suitable foundations for modelling in an ITS. We describe experiments performed to assess their effectiveness and we describe the ACME system built to explore modelling techniques for ITS.
Analysis and Design of Forward Converter With Energy Regenerative Snubber

An energy regenerating snubber for a forward converter is presented. The proposed snubber uses a tertiary transformer winding and beneficially exploits transformers' leakage inductances. The proposed snubber is capable of resetting the transformer, as well as eliminating leakage inductance voltage spike across the power switch. The proposed snubber recycles the recovered energy partially to the load and partially back to the source. This paper presents theoretical analysis, simulation and experimental results.
GUARANTEED INITIALIZATION OF DISTRIBUTED SPACECRAFT FORMATIONS

In this paper we present a solution to the formation initialization (FI) problem for N distributed spacecraft located in deep space. Our solution to the FI problem is based on a three-stage sky search procedure that reduces the FI problem for N spacecraft to the simpler problem of initializing a set of sub-formations.
Methods for patient-level costing in the VA system: are they applicable to Canada?

In his article “Determination of VA Health Care Costs,” Barnett (2003 [this issue]) describes various methods available to estimate costs in the U.S. Veterans Affairs (VA) health care system. These methods include direct measurement, pseudo bills combining VA patient-level utilization data and non-VA cost lists, cost functions based on regression analysis using non-VA cost estimates, and average cost databases. The need for these methods arises from the fact that VAhospitals do not prepare patient bills, the primary source of health care costs used in U.S. health economic studies. Barnett (2003) suggests that the principles of cost determination described in his article can be applied to other settings where billing data are not available. This is the case in Canada, where acute-care hospitals are publicly funded through global operating budgets. Because very few hospitals have information systems that produce reliable patient-level costing data, Canadian health economists rely on similar cost-estimation methods to those detailed by Barnett. The parallels between VAhealth care costing methods and those used by Canadian investigators are detailed in the remainder of this commentary.
Competitive dominance among sessile marine organisms in a high Arctic boulder community

In most hard substrate environments, space is a limiting resource for sessile organisms. Competition for space is often high and is a structuring force within the community. In the Beaufort Sea's Boulder Patch, crustose coralline red algae are major space occupiers. This research determined if coralline algae were com- petitively dominant over other sessile organisms. To test this hypothesis, overgrowth was documented in terms of ''winners'' and ''losers'' on the contact borders between different species. Crustose corallines occurred in over 80% of the observed interactions but were only winners in approximately half of them. Most frequently, bry- ozoans, tunicates, and sponges were superior competi- tors over crustose corallines, while at the same time these invertebrate groups were among the least abundant space occupiers.
Relationship of DNA double-strand breaks to synapsis in Drosophila.

The relationship between synaptonemal complex formation (synapsis) and double-strand break formation (recombination initiation) differs between organisms. Although double-strand break creation is required for normal synapsis in Saccharomyces cerevisiae and the mouse, it is not necessary for synapsis in Drosophila and Caenorhabditis elegans . To investigate the timing of and requirements for double-strand break formation during Drosophila meiosis, we used an antibody that recognizes a histone modification at double-strand break sites, phosphorylation of HIS2AV (γ-HIS2AV). Our results support the hypothesis that double-strand break formation occurs after synapsis. Interestingly, we detected a low (10-25% of wildtype) number of γ-HIS2AV foci in c(3)G mutants, which fail to assemble synaptonemal complex, suggesting that there may be both synaptonemal complex-dependent and synaptonemal complex-independent mechanisms for generating double-strand breaks. Furthermore, mutations in Drosophila Rad54 ( okr ) and Rad51 ( spnB ) homologs cause delayed and prolonged γ-HIS2AV staining, suggesting that double-strand break repair is delayed but not eliminated in these mutants. There may also be an interaction between the recruitment of repair proteins and phosphorylation.
Historically browsed jewelweed populations exhibit greater tolerance to deer herbivory than historically protected populations

Summary 1. Browsing by overabundant white-tailed deer (Odocoileus virginianus) has altered ecological relationships in forest communities across eastern North America. Recent but limited work suggests that deer browsing also selects for particular plant defensive traits. 2. We hypothesized that browsing by deer has imposed selection on defensive traits in an annual native wildflower, orange jewelweed (Impatiens capensis). 3. To test this hypothesis, we collected individuals from 26 natural populations across a 5000 km 2 area in New York State, USA. Half of these populations were historically protected from deer and half were exposed to heavy browsing. We planted individuals in common gardens subjected to natural deer browsing or no browsing. 4. Individuals from historically browsed populations exhibited significantly higher tolerance than those from historically protected populations. Herbivory by deer reduced lifetime fruit production by only 20% in historically browsed populations, as opposed to 57% in historically protected populations. Two mechanisms were correlated with this increased tolerance: increased number of flowering days and increased fruits per flowering node. 5. Synthesis. The increased tolerance of historically browsed populations suggests that these populations evolved increased tolerance or that historically protected populations lost tolerance over time. Variation in tolerance traits in native plant species may allow them to persist in the face of rapid ecological change.
POSTFLEDGING FORSTER'S TERN MOVEMENTS, HABITAT SELECTION, AND COLONY ATTENDANCE IN SAN FRANCISCO BAY

Abstract. Relatively little is known about birds during the postfledging period when flighted chicks have left the nest and must learn to forage independently. We examined postfledging movements, habitat selection, and colony attendance of Forster's Terns (Sterna forsteri) radio-marked just before they fledged in San Francisco Bay, California. The proportion of the day spent at their natal colony declined as juveniles aged, from 65% at the time of fledging to 5000 m by their fifth week. Time of day also influenced colony attendance, with older terns spending more time at the colony during nighttime hours (20:00 to 05:00) than during the day (06:00 to 19:00), when they were presumably foraging. Home ranges and core-use areas averaged 12.14 km2 and 2.23 km2, respectively. At each of four spatial scales of analysis, postfledgin...
Quantifying Lipid Contents in Enveloped Virus Particles with Plasmonic Nanoparticles

NIH grants RO1CA138509 (B.M.R.), RO1A1064099 (S. G., and 1R56Al104393 (B.M.R. and S. G.; Ethan Edmonds support (CHE 1156666)
The Association of Spinal and Gastroesophageal Anomalies Case Report and Review

Severe cervical radiculopathy occurred in a child with gastroesophageal dupli cation who had a previously unrecognized vertebral malformation. We review the literature on the association of vertebral and gastroesophageal anomalies and discuss the recent studies in human embryology which detail the relations of notochord to endoderm and neural ectoderm at about 3 weeks of gestation. This case illustrates the opportunity of preventing nerve root or spinal cord compromise due to such vertebral anomalies when the possibility of their association with gastroesophageal duplication is considered.
Reconfigurable sampling of the electric field at the reflecting surface of folded arrayed waveguide grating multiplexers

We describe the use of a reflective arrayed waveguide grating multiplexer in conjunction with a digital micromirror device to modulate the electric field distribution in the grating. Modulation of the electric field is accomplished by turning individual digital mirrors on and off. By imposing a reconfigurable grating superstructure on the digital mirror array, we can change the free-spectral range of the device and alter the overall transmission spectra. The experimental results are in excellent agreement with model calculations. This type of a device is expected to be useful in generation of reconfigurable sequences of ultrashort pulses.
Computation-free preconditioners for the parallel solution of power system problems

Solution of a set of linear equations Ax=b is a recurrent problem in power system analysis. Because of computational dependencies, direct methods have proven to be of limited value in both parallel and highly vectorized computing environments. The preconditioned conjugate gradient method has been suggested as a better alternative to direct methods. The preconditioning step itself is not particularly well suited to parallel processing. Partitioned inverse representations of A are better suited to high performance computation. However, obtaining the partitioned inverse matrices can be expensive. This paper describes two techniques for preconditioning based on the partitioned inverses where the preconditioner matrix is obtained directly from an incomplete factorization without the need for additional numerical computation. Experiments indicate a 50% reduction in solution time in a parallel environment.
CARE Track for Advanced Cancer: Impact and Timing of an Outpatient Palliative Care Clinic

Abstract Background: Studies suggest that outpatient palliative care can reduce hospitalization and increase hospice utilization for patients with cancer, however there are insufficient resources to provide palliative care to all patients from time of diagnosis. It is also unclear whether inpatient consultation alone provides similar benefits. A better understanding of the timing, setting, and impact of palliative care for patients with cancer is needed. Objectives: The purpose of this study was to measure timing of referral to outpatient palliative care and impact on end-of-life (EOL) care. Design: The Comprehensive Assessment with Rapid Evaluation and Treatment (CARE Track) program is a phased intervention integrating outpatient palliative care into cancer care. In Year 1 patients were referred at the discretion of their oncologist. Setting: Academic medical center. Measurements: We compared EOL hospitalization, hospice utilization, and costs of care for CARE Track patients compared to those never seen ...
Position of Ag reflection layer and its effect on GaN LED light extraction efficiency

We uses Finite Difference Time Domain (FDTD) based simulations directly compare six state of art GaN LED structures. The six structures include three conventional LEDs, and three LEDs with a patterned sapphire substrate and SiO2 nanorod array. Since Ag reflection layers have been used recently in Gallium Nitride (GaN) LEDs to improve light extraction efficiency. A reflection layer is placed either between the U-GaN and sapphire layers or at the bottom of the sapphire substrate in our simulation. We present the effect of Ag reflection layer position on output power for each structure. With the reflection layer located at the bottom of the sapphire substrate, we show that changing sapphire substrate height strongly affects light extraction efficiency. The conventional LED with an appropriate sapphire height design and a bottom Ag reflector can be the most efficient device.
Electronics development for the ATLAS liquid argon calorimeter trigger and readout for future LHC running

Abstract The upgrade of the LHC will provide 7 times greater instantaneous and 10 times greater total luminosities than assumed in the original design of the ATLAS Liquid Argon (LAr) Calorimeters. Radiation tolerance criteria and an improved trigger system with higher acceptance rate and longer latency require an upgrade of the LAr readout electronics. In the first upgrade phase in 2019–2020, a trigger readout with up to 10 times higher granularity will be implemented. This allows an improved reconstruction of electromagnetic and hadronic showers and will reduce the background for electron, photon and energy-flow signals at the first trigger level. The analog and digital signal processing components are currently in their final design stages and a fully functional demonstrator system is operated and tested on the LAr Calorimeters. In a second upgrade stage in 2024–2026, the readout of all 183,000 LAr Calorimeter cells will be performed without trigger selection at 40 MHz sampling rate and 16 bit dynamic range. Calibrated energies of all cells will be available at the second trigger level operating at 1 MHz, in order to allow further mitigation of pile-up effects in energy reconstruction. Radiation tolerant, low-power front-end electronics optimized for high pile-up conditions are currently being developed, including pre-amplifier, ADC and serializer components in 65–180 nm technology. This contribution will give an overview of the future LAr readout electronics and present research results from the two upgrade programs.
The patterns of schizophrenia in adolescence; a report on 50 cases of adolescent girls.

A survey is presented of the patterns of schizophrenia seen in adolescent girls. A preliminary study of 50 cases indicates that there are three types based on differences in pre-psychotic development. Each group has special features in diagnosis, prognosis, and treatment.
Reef Fishes, Seaweeds, and Corals

The coral-seaweed-herbivore triangle is an accepted generalization embedded within a highly complex web of biotic interactions and abiotic conditions that bring exceptions. The pattern is confirmed by observations that herbivorous fishes and urchins can have very strong effects on the standing crop of reef macroalgae, thereby opening space for corals to thrive. However, other factors, such as the abundance and distribution of territorial damselfishes, shelter for schooling herbivores, water motion, and nutrient flux, as well as multiple stressors on corals, can modify this basic pattern, sometimes strongly. High levels of herbivory lead to dominance by low-lying algae, including crustose corallines that may foster coral settlement. The intensity of herbivory by schooling fishes often varies unimodally with depth: low in very shallow water due to wave stress and other factors limiting accessibility by fishes, high at moderate depths, and low in deeper water where coral growth that provides shelter for fishes declines. Dense stands of macroalgae tend to thrive where herbivores are rare due to lack of habitat complexity that provides refuges from predation. Herbivorous damselfishes can act as natural cages by inhibiting schooling grazers and maintaining a high diversity of mid-successional algae within their territories via moderate grazing (intermediate-predation effect). These algal mats not only inhibit coral growth, but also serve as localized refugia for small invertebrates and newly settled fishes. Nutrients also play a pivotal role in structuring benthic algal productivity, standing crops, and species assemblages. Besides directly consuming corals or algae, reef fishes can also affect invertebrate corallivores and herbivores, causing subsequent indirect effects on reef benthos. Examples include predation on the corallivorous crown-of-thorns seastar and herbivorous sea urchins, the latter causing halos around patch reefs where urchins remain near cover. From a management perspective, conserving herbivores is clearly important for keeping reef algae in check. Maintaining both the abundance and species diversity of herbivores of a variety of sizes, especially via marine reserves, is likely the best means of ensuring that macroalgae do not displace corals. Such rules of thumb are likely essential for fostering the ecological resilience of coral reefs, especially in the context of a warming and acidifying ocean.