cssi/SciSciGPT-SciSciNet huggingface dataset:
Asymptotics of cross-validated risk estimation in estimator selection and performance assessment

Abstract Risk estimation is an important statistical question for the purposes of selecting a good estimator (i.e., model selection) and assessing its performance (i.e., estimating generalization error). This article introduces a general framework for cross-validation and derives distributional properties of cross-validated risk estimators in the context of estimator selection and performance assessment. Arbitrary classes of estimators are considered, including density estimators and predictors for both continuous and polychotomous outcomes. Results are provided for general full data loss functions (e.g., absolute and squared error, indicator, negative log density). A broad definition of cross-validation is used in order to cover leave-one-out cross-validation, V -fold cross-validation, Monte Carlo cross-validation, and bootstrap procedures. For estimator selection, finite sample risk bounds are derived and applied to establish the asymptotic optimality of cross-validation, in the sense that a selector based on a cross-validated risk estimator performs asymptotically as well as an optimal oracle selector based on the risk under the true, unknown data generating distribution. The asymptotic results are derived under the assumption that the size of the validation sets converges to infinity and hence do not cover leave-one-out cross-validation. For performance assessment, cross-validated risk estimators are shown to be consistent and asymptotically linear for the risk under the true data generating distribution and confidence intervals are derived for this unknown risk. Unlike previously published results, the theorems derived in this and our related articles apply to general data generating distributions, loss functions (i.e., parameters), estimators, and cross-validation procedures.
Sedation in Adults Receiving Mechanical Ventilation: Physiological and Comfort Outcomes

The need for sedative therapy in critical care adults receiving mechanical ventilation is well established; 85% of intensive care unit (ICU) patients are given intravenous sedatives to help attenuate the anxiety, pain, and agitation associated with mechanical ventilation.1–4 The overall goals of the sedation are to provide stability in physiological status and comfort.4–6 However, use of inappropriately high or low levels of sedation in critically ill adults has marked risks. Inappropriately high levels of sedation, which are associated with the use of continuous intravenous infusions of sedatives,7 may lead to alterations in respiratory drive, inability to maintain and protect the airway, and unstable cardiovascular status,8 as well as prolonged duration of mechanical ventilation and ventilator-associated pneumonia.9–11 In addition, sedation increases the risk for depressive symptoms, delirium, and delusional memories of the ICU stay.12,13 Conversely, inadequate levels of sedation may result in agitation, placing intubated patients at risk for self-extubation, unstable hemodynamic status, and physical harm or injury.14 Sedation management is a multidisciplinary process, but in most ICUs, nurses are primarily responsible for making the decisions about administration and titration of sedatives.15–17 Nurses adjust sedation according to a wide range of information, including subjective assessments of patients’ amnesia and comfort needs, need to prevent self-injury by patients, efficiency of care, and the nurses’ own beliefs and interactions with patients’ families.15,18,19 Decisions to alter sedation on the basis of this non-systematic information may result in either inadequate or excessive sedation.18,19 Therefore, the first step in improving patients’ outcomes is to systematically describe physiological status and comfort outcomes for various levels of sedation. Although sedation protocols reduce the duration of mechanical ventilation20–23 and ICU costs,22,24 most protocols use a single measure of sedation, either a sedation scale or processed electroencephalographic findings, to titrate sedative therapy.25 Levels of sedation should differ according to an individual patient’s needs and disease process, resulting in deep levels of sedation for some patients and lighter levels for others.4 However, the extent to which these various levels of sedation actually achieve sedation outcomes of a stable physiological status and comfort is unknown. Therefore, the specific aim of this prospective study was to describe the relationship among sedation, stability of physiological status, and comfort during a 24-hour period in patients receiving mechanical ventilation.
The determination of corporate optimal capital structure under value maximization and informational asymmetry

Abstract In this article we examine the optimal capital structure of the firm under conditions of informational asymmetry, i.e., when the manager of the firm is viewed by the market as possessing inside information about the firm's future profitability. Unlike previous research on this topic, in this study we preserve the objective of value maximization when examining the signaling property of corporate capital structure. We also recognize explicitly the other consequences of debt financing on the value of the firm. An integrated analysis of the capital structure problem within the context of rational expectation is presented, and a signaling equilibrium is derived and discussed. The nature of the welfare costs that emerge from the existence of informational asymmetry is also analyzed.
On Comparing Income Maintenance Alternatives

This paper seeks to clarify choices in income maintenance, not to advocate a particular policy alternative. It makes explicit the trade-offs between competing objectives that are required of policymakers, but often obscured by polemics about the advantages or disadvantages of particular transfer mechanisms (e.g., negative income taxes, child allowances, demogrants). The paper first presents a critique of contemporary public debate on welfare reform and antipoverty cash transfer schemes. The next section distinguishes among the goals of reforming the present system of public assistance, substantially reducing American poverty, and making both the tax system and the social distribution of income more equitable. There follows a discussion of six criteria for evaluating and comparing alternative measures to one or another of these goals. The paper concludes with an application of the evaluative scheme to the welfare reform alternatives considered by the Nixon Administration in the spring of 1969.
An Environment for Treating Youthful Offenders: The Robert F. Kennedy Youth Center.

Abstract This article opens with a quotation, concerning the goals of the Robert P. Kennedy Youth Center (KYC). It describes both the philosophical stance and the implementation of that philosophy within the center. Issues discussed range from the administrative structure through descriptions of inmate classification and treatment. Educational and vocational programs as well as the token economy systems are discussed. The major evaluative and research studies that were done at KYC are summarized. Although the center has ceased to be a demonstration project, the findings from KYC are deemed to be more important now than at the time the studies were conducted as they, individually and collectively, reflect on a model for corrections that is relevant for the future.
THE EFFICACY OF VARIOUS KINDS OF ERROR FEEDBACK FOR IMPROVEMENT IN THE ACCURACY AND FLUENCY OF L2 STUDENT WRITING

Abstract This research uses experimental and control group data to show that students’ correction of grammatical and lexical error between assignments reduces such error in subsequent writing over one semester without reducing fluency or quality. A second study further examines how error correction should be done. Should a teacher correct errors or mark errors for student self-correction? If the latter, should the teacher indicate location or type of error or both? Measures include change in the accuracy of both revisions and of subsequent writing, change in fluency, change in holistic ratings, student attitudes toward the four different kinds of teacher response, and time required by student and teacher for each kind of response. Findings are that both direct correction and simple underlining of errors are significantly superior to describing the type of error, even with underlining, for reducing long-term error. Direct correction is best for producing accurate revisions, and students prefer it because it is the fastest and easiest way for them as well as the fastest way for teachers over several drafts. However, students feel that they learn more from self-correction, and simple underlining of errors takes less teacher time on the first draft. Both are viable methods depending on other goals.
Gene expression following low dose inhalational Francisella tularensis (SchuS4) exposure in Balb/c mice and the potential role of the epithelium and cell adhesion

Abstract Interactions between Francisella tularensis and the host are slowly being elucidated. Microarray technology was used to further characterise the response of Balb/c mice after inhalation of the virulent F. tularensis , SchuS4. The validated array data revealed changes in expression of 476 genes across a 96 h time course following infection ( p ≤ 0.05). These data confirm down-regulation of the toll-like receptor pathway (TLR3, 4, 5, 7 and 8), and the induction of IFN-γ inducible genes (T-cell specific GTPase, β2 microglobulin and interleukin 21). The overall response appears to be two staged with an initial up-regulation of genes involved in apoptosis, TNFα production and antigen presentation. This is followed by a large alteration of expression at 96 h as the host succumbs to infection. A key regulatory time-point has been identified at 24 h post challenge, where several transcriptional events may predicate the progression of infection; these include transcriptional regulators of inflammation and proteolytic pathways. Pathway analysis indicates a novel role for cell–cell adhesion and extracellular matrix modulation in infection. Transcripts representing cellular junctions, focal adhesion and adherens junctions changed following infection. Additionally, aspects of extracellular matrix remodelling have been confirmed at the protein level, suggesting an important role of the respiratory epithelium in host response to F. tularensis warranting further study.
DIBUTYRL CYCLIC AMP (DBCAMP) DOES NOT ALTER AMINO ACID ACCUMULATION BY BRUSH BORDER MEMBRANE VESICLES (BBMV)

DIBUTYRL CYCLIC AMP (DBCAMP) DOES NOT ALTER AMINO ACID ACCUMULATION BY BRUSH BORDER MEMBRANE VESICLES (BBMV)
A METHOD FOR DEVELOPING BRACHYURAN EGGS IN VITRO1

The larvae of six species of Brachyura have been successfully hatched by detaching the eggs from the female, placing them in compartmented boxes, and maintaining them on an Eberbach variable speed shaker at constant temperatures at different salinities. In addition to providing thousands of normal larvae of known species for experimental purposes, the method has the following advantages: it provides adequate aeration, prevents the spread of fungi and protozoans throughout the egg mass, and permits the use of a relatively small number of eggs from the same animal in a limited space.
Verification of a Mesoscale Data-Assimilation and Forecasting System for the Oklahoma City Area during the Joint Urban 2003 Field Project

Abstract The National Center for Atmospheric Research (NCAR) and the U.S. Army Test and Evaluation Command have developed a multiscale, rapid-cycling, real-time, four-dimensional data-assimilation and forecasting system that has been in operational use at five Army test ranges since 2001. This system was employed to provide operational modeling support for the Joint Urban 2003 (JU2003) Dispersion Experiment, conducted in Oklahoma City, Oklahoma, during July 2003. To better support this mission, modifications were made to the nonlocal boundary layer (BL) parameterization (known as the Medium Range Forecast scheme) of the fifth-generation Pennsylvania State University–NCAR Mesoscale Model, in order to improve BL forecasts. The NCEP–Oregon State University–Air Force–Hydrologic Research Laboratory land surface model was also improved to better represent urban forcing. Verification of the operational model runs and retrospectively simulated cases show 1) a significantly reduced low bias in the forecast surface...
Intradistrict Resource Reallocation for Latino English Language Learners: An Exploratory Multiple Case Study Approach.

This article seeks to contribute to the recent discussion regarding school finance, teacher quality, and English language learners (ELLs) based on a comparative study within a school district with a significant ELL population. The study described in this article utilizes an exploratory multiple case study methodology to examine the complex relationship between resource allocation (both fiscal and personnel) and educational outcomes for ELL students. This study addresses whether there are differences in resource allocation between a high-ELL, Program Improvement, Title I school and a high-ELL, non-Program Improvement, Title I school within a single district. The study findings show significant differences in the educational resources allocated between the selected schools and suggest that resources (both fiscal and personnel) do in fact impact school outcomes. This study has research, policy, and practice implications related to resource allocation that affect school achievement, equity, and social justice...
Perceived versus actual factors associated with adoption and maintenance of an evidence-based physical activity program

The public health burden of arthritis requires the dissemination of evidence-based physical activity (PA) programs for arthritis. This study examined perceived vs. actual factors related to the adoption and maintenance of PA programs and Fit and Strong! Six focus groups (n = 46) were conducted in two states with potential Fit and Strong! providers. Key informant interviews (n = 18) were conducted with actual Fit and Strong! providers. Participant interest was a primary motivator for PA program adoption in both focus groups and key informant interviews. Fit and Strong’s evidence base was a motivator for adoption among focus group participants. The primary perceived barrier to adopting Fit and Strong! among focus group participants was cost/resource limitations compared to scheduling among key informants. Evidence-based programs need to craft different messages to deal with barriers perceived and experienced by providers engaged in specific stages of the translation process.
Optimal design of elastic rods under axial gravitational load using the maximum principle

Abstract Optimal design problems for structural elements in equilibrium often come in pairs in which the cost function for one problem becomes a constraint for the second. In particular, the problem of minimizing structural volume or weight under size and stress constraints has a dual in which potential energy is minimized for fixed volume of material. These dual problems are solved here for a linearly elastic rod hanging from a rigid support. The design variable is the cross-sectional area of the rod. The method used is the Maximum Principle of Pontryagin and Hestenes, rather than the function space methods used by others for similar problems.
Luminescent properties of solution-grown ZnO nanorods

The optical properties of solution-grown ZnO nanorods were investigated using photoluminescence and cathodoluminescence. The as-grown nanorods displayed a broad yellow-orange sub-band-gap luminescence and a small near-band-gap emission peak. The sub-band-gap luminescence can only be observed when exciting above band gap. Scanning cathodoluminescence experiments showed that the width of the sub-band-gap luminescence is not due to an ensemble effect. Upon reduction, the sub-band-gap luminescence disappeared and the near-band-gap emission increased. Compared to ZnO powders that are stoichiometric and oxygen deficient, we conclude that the yellow-orange sub-band-gap luminescence most likely arises from bulk defects that are associated with excess oxygen.
Determination of molecular surface structure, composition, and dynamics under reaction conditions at high pressures and at the solid-liquid interface.

In the last two decades, surface-science experiments and techniques have been developed to focus on obtaining molecular information under reaction conditions at high pressures (near or above 1 bar) and liquid interfaces. This Minireview describes the results of these studies obtained by surface-sensitive laser spectroscopies, scanning tunneling microscopy, and X-ray spectroscopies usually practiced at a synchrotron light source. The use of model surfaces, single crystals, and monodisperse nanoparticles with variable size (1–10 nm) and shape facilitates meaningful interpretation of the experimental data. These methods allow evaluation of the molecular structures of intermediates, oxidation states of metals, and mobility of adsorbants. New techniques that are likely to make major contributions to the investigation of surfaces under reaction conditions are also discussed.
The risk of developing a vancomycin-resistant Enterococcus bloodstream infection for colonized patients

Epidemiology Between 2 to 4 million patients each year develop health care-acquired infections in the United States. Infection resulting from vancomycin-resistant Enterococcus (VRE) is now the second to third most common cause of nosocomial infections in the United States. VRE is most often transmitted by the contaminated hands, clothing, and equipment of health care workers. Patients with VRE bloodstream infections (BSIs) have increased rates of recurrent BSI (16.9% vs 3.7%, respectively, P P = .04) compared with those with vancomycin-susceptible BSI. Additionally, transfer of the gene responsible for vancomycin resistance to S aureus has been demonstrated in vitro, and reports of clinical infections because of vancomycin-resistant Staphylococcus aureus have been reported from many areas of the world, including the United States. Risk factors for VRE colonization and infection include prolonged length of hospital stay, use of broad-spectrum antibiotics, having an indwelling invasive device, and close proximity to another VRE-colonized or -infected patient; however, risk factors for developing VRE BSI among colonized patients have not been fully described. Infection Control Infection control measures for VRE include antibiotic-usage control, reducing contamination of the environment with proper cleaning and disinfection, and reducing contamination of health care workers by use of contact precautions. Health care-acquired BSIs can also be effectively controlled by closely following central venous line prevention guidelines and complying with the central venous line bundle. Control and prevention of VRE colonization and thus infection would be expected to reduce morbidity, reduce health care costs, and save lives.
Nitrogen fixation activity of a filamentous, nonheterocystous cyanobacterium in the presence and absence of exogenous, organic substrates

Nitrogen-starved cells of the filamentous, nonheterocystous cyanobacterium, Plectonema boryanum 581, were cultured microaerophilically in the presence and absence of exogenous, organic substrates (fructose, glucose, sucrose, and CO2) to determine the effect of an external carbon source on nitrogenase activity. In unsupplemented and in fructose-, glucose-, and sucrose-enriched cultures, nitrogenase activity was detected 75 min after the exclusion of oxygen, compared to 90 min for the CO2-supplemented cultures. Nitrogenase activity increased for more than 40 h at levels unique to each carbon-supplemented and unsupplemented culture. The relationship between nitrogenase activity, carbon source, and glycogen content is discussed.
Tapping Technology: Creating Web-Based Tutorials for Master Gardeners

ABSTRACT Many successful Extension programs depend on the knowledge and expertise of volunteer Master Gardeners. It is important that Master Gardeners take advantage of research-based information and tips and tricks to finding quality information on the Web. This article outlines a successful cooperative project in which segments of a traditional classroom instruction session for Master Gardeners were modified into tutorials. The tutorials were then offered via the Web and used as part of the Master Gardener training.
A quantitative CFD benchmark for Sodium Fast Reactor fuel assembly modeling

Abstract This paper details a CFD model of a 19-pin wire-wrapped sodium fuel assembly experiment conducted at Oak Ridge National Laboratory in the 1970s. Model sensitivities were tested for cell size, turbulence closure, wire-wrap contact, inlet geometry, outlet geometry, and conjugate heat transfer. The final model was compared to the experimental results quantitatively to establish confidence in the approach. The results were also compared to the sub-channel analysis code COBRA-IV-I-MIT. Experiment and CFD computations were consistent inside the bundle. Comparison between experimental temperature measurements from thermocouples embedded in the heated length of the bundle are consistently reproducible with CFD code predictions across a wide range of operating conditions. The demonstrated agreement provides confidence in the predictive capabilities of the approach. However significant discrepancy between the CFD code predictions and the experimental data was found at the bundle outlet. Further sensitivity studies are presented to support the conclusion that this discrepancy is caused by significant uncertainty associated with the experimental data reported for the bundle outlet.
Attenuation of the influenza virus sickness behavior in mice deficient in Toll-like receptor 3.

Certain sickness behaviors occur consistently in influenza-infected humans and mice. These include body temperature changes, somnolence, and anorexia. Several cytokines serve as mediators of the influenza acute phase response (APR), including these sickness behaviors, and one likely inducer of these cytokines is dsRNA produced during viral replication. TLR3 is known to be one of the host cellular components capable of recognizing dsRNA and activating cytokine synthesis. To determine the role of TLR3-detected viral dsRNA in the causation of viral symptoms, TLR3-deficient mice (TLR3 knockouts, or KOs) were infected with a marginally-lethal dose of mouse-adapted X-31 influenza virus. TLR3 KOs and their wild-type (WT) controls were monitored for baseline body temperature, locomotor activity, and sleep profiles prior to infection. Both mouse strains were then infected and monitored for changes in these sickness behaviors plus body weight changes and mortality for up to 14 days post-infection. Consistent with the observations that influenza pathology is reduced in TLR3 KOs, we showed that hypothermia after post-infection day 5 and the total loss of body weight were attenuated in the TLR3 KOs. Sleep changes characteristic of this infection model [particularly increased non-rapid-eye-movement sleep (NREMS)] were also attenuated in TLR3 KOs and returned to baseline values more rapidly. Locomotor activity suppression was similar in both strains. Therefore virus-associated dsRNA detected by TLR3 appears to play a substantial role in mediating several aspects of the influenza syndrome in mice.
Estimating Effective Sample Size for Monitoring Length Distributions: A Comparative Study of Georges Bank Groundfish

Abstract Because of the aggregative behavior of fish, effective sample size is more meaningful than total sample size for estimating the length distribution of a fish stock. We estimated the effective sample sizes for mean length distributions of six groundfish species from Georges Bank using data collected by a Study Fleet Program implemented by the School for Marine Science and Technology (SMAST) at the University of Massachusetts–Dartmouth. Both statistical and simulation methods were applied. Skewness and kurtosis were also used as proxies for length distributions. The statistical result suggests that the estimated effective sample size is much less than the number of fish measured in the initial SMAST Study Fleet Program, while the simulation method suggests that for most groundfish species reducing the total number of fish to 20% will not affect the variance, skewness, and kurtosis of the population length. For the SMAST Study Fleet Program, increasing the number of sampling stations can improve sam...
Nodal Control in a Vibrating Beam

Vibration control is an important engineering problem and many methods for both active and passive vibration absorption have been developed. This paper deals with developing a method to achieve nodal control at the point of excitation in a Bernoulli-Euler beam. Singh and Ram in [3] have shown that under certain conditions that have been characterized in [3] the steady state motion of a certain degree of freedom in a harmonically excited conservative system may be absorbed by both passive and active means. Ram in [1] has developed a method to eliminate the steady state motion of a prescribed location in a continuous system like rod under the influence of a harmonic excitation. He has presented a closed form solution for the control gain in terms of infinite product of eigenvalues. This thesis extends the approach in [1] to achieve nodal control for suppressing vibration at prescribed location in beams and provides a simpler formula for the control gain in terms of eigenfunctions. It is established that, for a uniform Bernoulli-Euler beam, the steady state motion at the point of excitation can be absorbed by means of a control force determined from displacement information at the point of application. A closed form solution for the control gain is presented and a criterion for implementing the control by active and passive means is developed. The result for the control gain is generalized for the case of a non-uniform beam. It is also shown through some examples that the theory can be also applied to eliminate the steady state motion at any desired location other than the point of excitation. Analysis is also performed to determine the optimal control force and investigate the stability of the overall system. Several controllability graphs are shown and meaningful conclusions are drawn from these graphs. An experiment is designed to validate the proposed theory and display its practicality. The developed theory will provide a strong foundation for realizing realistic and convenient methodologies in control applications in cases like surgical procedures, drilling and turning operations etc. However, one of the many direct applications of this method is structural vibration control in an aircraft wing. Several measurements such as vibrational response, air temperature, wind velocity etc are required in order to monitor flight conditions in an aircraft. These data also assist the pilot in flying the aircraft. Sensors and data collection circuitry form an entire network of the electrical wiring all in and around the airplane body. Data acquisition devices are also located on the wing of the airplane. Shielding of these devices from undesirable vibration of the wing is critical in order to avoid noise in the gathered data and prevent physical damage. Exclusion of steady state vibration at the locations of these devices provides the motivation for this investigation.
Closed form solution for strain energy release rate distribution in debonded one-edge free postbuckled composite flanged joints

Abstract A closed form model predicting debond growth in composite flanged joints is presented. This model calculates the non-uniform distribution of strain energy release rate (G) across the crack front. Such a model is useful for assessing the effects of partial debonds in adhesively-bonded joints that are subjected to compressive loads. The model’s accuracy is gauged by comparison of the G profile prediction with finite element analysis (FEA) based virtual crack closure technique (VCCT) calculations. For the woven glass/epoxy joints analyzed, it was found that the closed form model predicted the peak values of G to within 20% of the FEA calculated values when the applied far-field strain eo was greater than 1.3 times the strain at which the flange first buckles, i.e., the critical buckling strain ecr. At moderate loads (eo
Measurement of Debye length in laser‐produced plasma

A technique for measuring the Debye length of an expanded laser produced plasma was devised. With an independent measurement of electron density, the plasma electron temperature could then be ascertained.
NIST/IEEE Virtual Manufacturing Automation Competition: from earliest beginnings to future directions

This paper provides an overview of the National Institute of Standards and Technology (NIST)/IEEE Virtual Manufacturing and Automation Competition (VMAC). Detailed information will be provided on the competition's objectives, history, and operation. In addition, the supporting software infrastructure will be discussed.
KGF boosts thymic archiTECture

[Comment on Rossi et al, page 3803][1]The thymic epithelium supports thymocyte development, from entry of progenitors, through T-lineage commitment, positive and negative selection, and final export. KGF boosts thymopoiesis by working directly on thymic epithelial cells. The thymus is essential not
The conception of audience in Perelman and Isocrates: Locating the ideal in the real

The author compares two theoretical models which develop constructs of an ideal audience. Chaim Perelman's universal audience serves a methodological function within the New Rhetoric which provides for the examination of philosophical arguments on values. Implicit within the work of Isocrates is a competing image which asserts that the ideal audience is empowered by the conditions of argument to engage the advocate in discursive praxis to construct and embody a consensus on contingency-driven value debates. The author concludes that the concept of an ideal audience will be most valuable where interest in adherence to theses is less central than attendance to relationships born in and borne by discourse. Such a view has purchase within a constitutive view of rhetorical relations which asserts that the most useful role for argument is as an invitation to engagement. The situation of argumentation within a deontological ethics requires the partnership and participation of individuals in a mutually constructed discursive praxis.
Legal literacy: Coproducing the law in technical communication

This article discusses the need for technical communicators to develop a more sophisticated understanding of the relationship between law and their work. The author reviews the discipline's literature regarding the relationship between law and technical communication and argues that technical communicators must learn to see themselves as coproducers of the law. To that end, the author offers pedagogical strategies for helping technical communication students develop skills for recognizing the legal implications of their work.
Geometry optimization in Cartesian coordinates: the end of the Z -matrix?

Geometry optimization directly in Cartesian coordinates using the EF and GDIIS algorithms with standard Hessian updating techniques is compared and contrasted with optimization in internal coordinates utilizing the well known Z-matrix formalism. Results on a test set of 20 molecules show that, with an appropriate initial Hessian, optimization in Cartesians is just as efficient as optimization in internals, thus rendering it unnecessary to construct a Z-matrix in situations where Cartesians are readily available, for example from structural databases of graphical model builders
Genetic Control of Recombination Partner Preference in Yeast Meiosis: Isolation and Characterization of Mutants Elevated for Meiotic Unequal Sister-Chromatid Recombination

Meiotic exchange occurs preferentially between homologous chromatids, in contrast to mitotic recombination, which occurs primarily between sister chromatids. To identify functions that direct meiotic recombination events to homologues, we screened for mutants exhibiting an increase in meiotic unequal sister-chromatid recombination (SCR). The msc (meiotic sister-chromatid recombination) mutants were quantified in spo13 meiosis with respect to meiotic unequal SCR frequency, disome segregation pattern, sporulation frequency, and spore viability. Analysis of the msc mutants according to these criteria defines three classes. Mutants with a class I phenotype identified new alleles of the meiosis-specific genes RED1 and MEK1, the DNA damage checkpoint genes RAD24 and MEC3, and a previously unknown gene, MSC6. The genes RED1, MEK1, RAD24, RAD17, and MEC1 are required for meiotic prophase arrest induced by a dmc1 mutation, which defines a meiotic recombination checkpoint. Meiotic unequal SCR was also elevated in a rad17 mutant. Our observation that meiotic unequal SCR is elevated in meiotic recombination checkpoint mutants suggests that, in addition to their proposed monitoring function, these checkpoint genes function to direct meiotic recombination events to homologues. The mutants in class II, including a dmc1 mutant, confer a dominant meiotic lethal phenotype in diploid SPO13 meiosis in our strain background, and they identify alleles of UBR1, INP52, BUD3, PET122, ELA1, and MSC1-MSC3. These results suggest that DMC1 functions to bias the repair of meiosis-specific double-strand breaks to homologues. We hypothesize that the genes identified by the class II mutants function in or are regulators of the DMC1-promoted interhomologue recombination pathway. Class III mutants may be elevated for rates of both SCR and homologue exchange.
Global shadowing of pseudo-Anosov homeomorphisms

We prove that if f: M2→ M2 is pseudo-Anosov and if g ⋍ f then there is a closed subset X ⊂ M2 and a continuous surjection π: X→ M that is homotopic to inclusion such that f ° π = π ° g|X.
Evolution of New Function through a Single Amino Acid Change in the Yeast Repressor Sum1p

The SUM1-1 mutation is an example of a single amino acid change that results in new function. Wild-type Sum1p in Saccharomyces cerevisiae is a DNA-binding repressor that acts locally, whereas mutant Sum1-1p forms an extended repressive chromatin structure. By characterizing a panel of mutations in which various amino acids replaced the critical residue, threonine 988, we found that threonine was required for wild-type function and that in the absence of threonine the association of Sum1p with DNA was reduced. Isoleucine, the amino acid in mutant Sum1-1p, was required for the novel spreading property. Thus, the SUM1-1 mutation results in both a loss and a gain of function. The presence of isoleucine caused Sum1-1p to self-associate, a property that may promote spreading. In addition, isoleucine enabled Sum1-1p to associate with the origin recognition complex (ORC) and accumulate near ORC binding sites. Thus, both threonine and isoleucine at position 988 enable Sum1p to form intermolecular interactions. We propose that interaction domains may be hotspots for gain-of-function mutations because alterations in such domains have the potential to redirect a protein to new sets of binding partners. In addition, self-association of chromatin proteins may promote the formation of extended chromatin structures.
Catch Composition and Reproduction of the Spiny Lobster Panulirus versicolor at Palau

Abstract Diver catches of the spiny lobster Panulirus versicolor contribute to a tropical small-scale fishery at Palau, Western Caroline Islands. When commercial catches were sampled during October 1969-October 1970, the population had sustained relatively little fishing pressure and much of that had been of a subsistence nature. Males and females combined ranged from 5.6 cm to 13.2 cm in carapace length. The sexes were equally abundant overall, although females were significantly more abundant in the smallest size class and males were significantly more abundant in the larger size classes. Females attained reproductive maturity at about 8.2 cm carapace length, which is markedly above the size at which this species entered the fishery. A high level of sustained reproduction throughout the year is suggested by the data.
Lorenz Dominance and the Variance of Logarithms

The variance of logarithms is a widely used inequality measure which is well known to disagree with the Lorenz criterion. Up to now, the extent and likelihood of this inconsistency were thought to be vanishingly small. We find that this view is mistaken : the extent of the disgreement can be extremely large; the likelihood is far from negligible. (This abstract was borrowed from another version of this item.)
Anisotropic properties of strained viscoelastic fluids. I. A method for measuring strain birefringence

A mechanism has been devised for the purpose of introducing a sudden strain of calculable amount into a viscoelastic fluid. The principle of the apparatus relies upon the deformation caused by the rotation of an elliptical sleeve about a flexible tube containing polymer solution. An apparatus has been constructed which can produce a 90° rotation (with consequent deformation) in the period of one millisecond. The detection of the strained state is accomplished by means of strain birefringence. In this way, relaxation can be studied in concentrated solutions for a time range beyond one millisecond.
Augmenting Antitumor T-Cell Responses to Mimotope Vaccination by Boosting with Native Tumor Antigens

Vaccination with antigens expressed by tumors is one strategy for stimulating enhanced T-cell responses against tumors. However, these peptide vaccines rarely result in efficient expansion of tumor-specific T cells or responses that protect against tumor growth. Mimotopes, or peptide mimics of tumor antigens, elicit increased numbers of T cells that crossreact with the native tumor antigen, resulting in potent antitumor responses. Unfortunately, mimotopes may also elicit cells that do not crossreact or have low affinity for tumor antigen. We previously showed that one such mimotope of the dominant MHC class I tumor antigen of a mouse colon carcinoma cell line stimulates a tumor-specific T-cell clone and elicits antigen-specific cells in vivo, yet protects poorly against tumor growth. We hypothesized that boosting the mimotope vaccine with the native tumor antigen would focus the T-cell response elicited by the mimotope toward high affinity, tumor-specific T cells. We show that priming T cells with the mimotope, followed by a native tumor-antigen boost, improves tumor immunity compared with T cells elicited by the same prime with a mimotope boost. Our data suggest that the improved tumor immunity results from the expansion of mimotope-elicited tumor-specific T cells that have increased avidity for the tumor antigen. The enhanced T cells are phenotypically distinct and enriched for T-cell receptors previously correlated with improved antitumor immunity. These results suggest that incorporation of native antigen into clinical mimotope vaccine regimens may improve the efficacy of antitumor T-cell responses.
STRATEGIC BENEFITS TO FIRMS ISSUING PRIVATE EQUITY PLACEMENTS

For young technology firms, acquiring resources can often be costly due to the information asymmetry and uncertainty that exist surrounding the new technology. We contend that firms able to issue private equity can better manage their ability to mobilize three kinds of resources: capital, research partners, and commercial partners. We investigate the existence of long-term, strategic benefits to private placements, and a number of factors may determine the long-term effectiveness of this governance form. Overall, the empirical analyses demonstrates that private placements provide long-term benefits to firms by reducing hazards associated with information asymmetry. Copyright © 2003 John Wiley & Sons, Ltd.
Proton damage in LEDs with wavelengths above the silicon wavelength cutoff

Proton damage is investigated for LEDs with wavelengths of 1050 and 1550 nm. The results are compared to results for an advanced AlGaAs double heterojunction LED. Unlike the AlGaAs LED, light output degradation for the long wavelength LEDs became nonlinear with current after irradiation; more degradation was observed at lower forward currents. Minimal annealing was observed in the long wavelength LEDs during forward current injection. Mechanisms are proposed that are related to the material properties.
Adaptive scheduling and control using artificial neural networks and expert systems for a hierarchical/distributed FMS architecture

An adaptive expert scheduler that learns by itself and adapts to the dynamic FMS (flexible manufacturing system) environment was developed. This hybrid system uses a symbiotic architecture composed of expert systems and artificial neural networks and provides a learning scheme guided by past experience. The artificial neural networks recognize patterns in the tasks to be solved in order to select the best scheduling rule according to different criteria. The expert systems, on the other hand, drive the inference strategy and interpret the constraints and restrictions imposed by the upper levels of the control hierarchy of the flexible manufacturing system. The level of self-organization achieved provides a system with a higher probability of success than traditional approaches. >
Design of a Microfabricated Rankine Cycle Steam Turbine for Power Generation

This paper presents the system-level and component design of a micro steam turbine power plant-on-a-chip which implements the Rankine cycle for micro power generation. The microfabricated device consists of a steam turbine that drives an integrated micropump and generator. Two-phase flow heat exchangers are also integrated on-chip with the rotating components to form a complete micro heat engine unit, converting heat to electricity. The system-level design includes cycle analysis and overall performance predictions, accounting for the expected performance of miniaturized components, thermal and structural integrity of the microsystem, and system-level trade-offs for optimal overall performance. Operating principles and design studies are also presented for the core component, with emphasis on a multistage, planar, radial microturbine and a spiral groove viscous pump. Design consideration for two-phase flow heat exchangers, microbearings, seals and micro-generators are also presented. Expected power levels range from 1–12 W per chip with energy conversion efficiency in the range of 1–11%. This suggests power density of up to 12 kW/kg for this technology, which is an order of magnitude greater than competing technologies, such as thermoelectrics. This study suggests the viability of a micro Rankine power plant-on-a-chip, but also identifies critical engineering challenges that must be met for practical implementation.Copyright © 2003 by ASME
Nanostructural Differentiation between Live and Dead Escherichia coli Cells Using FT-IR Spectroscopy and Comparison of Detection Limits to Quantitative PCR (qPCR)

Fourier-transform infrared spectroscopy (FT-IR) utilizes nanostructural differences between bacterial cells for the rapid identification, classification, and differentiation of many species of bacteria, but most studies have used only live cells. A rapid and reliable method for determining the total number of live and dead bacterial cells in a food could prevent the distribution of unsafe products to consumers. In this study, infrared spectra (4000-700 cm-1) were collected using a Continuμm IR microscope attached to a ThermoNicolet Nexus 670 FT-IR spectrophotometer from varying concentrations of live and dead E. coli (ATTC 25922) cells. Spectra were analyzed using chemometric methods. Canonical variate analysis (CVA) and Mahalanobis distances (MD) quantified the spectral differences between 100% live and 100% dead bacteria, with linear discriminant analysis (LDA) using principal components able to successfully classify and differentiate between the two treatments (50 out of 50 correctly assigned). CVA and MD were also 100% successful in quantifying the spectral differences between 100% dead bacteria and samples containing as little as 0.1% live cells. The PLS method accurately quantified live cells in the presence of dead cells (R = 0.981), and Cooman plots showed clear separation between clusters of live and dead bacteria. To compare detection limits with qPCR, dead bacterial cells were treated with ethidium bromide monoazide (EMA) to prevent amplification of DNA from these cells and enable the detection of both live and dead cells using universal bacterial primer sets. The qPCR techniques using EMA-treated bacteria could also detect live cell concentrations as low as 0.1%. However, the total analysis time for detection using qPCR is ∼6 hours in comparison to ∼30 minutes using FT-IR. Therefore, FT-IR is a useful tool for the rapid differentiation between live and dead bacterial samples, even when the concentration of live bacteria is as low as 0.1% of the target microbe.
Optimizing electrostatic field calculations with the adaptive Poisson-Boltzmann Solver to predict electric fields at protein-protein interfaces. I. Sampling and focusing.

Continuum electrostatics methods are commonly used to calculate electrostatic potentials in proteins and at protein–protein interfaces to aid many types of biophysical studies. Despite their ubiquity throughout the biophysical literature, these calculations are difficult to test against experimental data to determine their accuracy and validity. To address this, we have calculated the Boltzmann-weighted electrostatic field at the midpoint of a nitrile bond placed at a variety of locations on the surface of the protein RalGDS, both in its monomeric form as well as when docked to four different constructs of the protein Rap, and compared the computation results to vibrational absorption energy measurements of the nitrile oscillator. This was done by generating a statistical ensemble of protein structures using enhanced molecular dynamics sampling with the Amber03 force field, followed by solving the linear Poisson–Boltzmann equation for each structure using the Applied Poisson–Boltzmann Solver (APBS) softwa...
Evaluation of contact resistance for isotropic electrically conductive adhesives

Electrically conductive adhesives are discussed and studied with ever-increasing interest as an alternative to solder interconnection in microelectronics circuit packaging. A similar level of scrutiny that is used to evaluate contact resistance performance for interconnections made with solder and separable connectors is necessary for electrically conductive adhesives. Experience with solder interconnection and separable connectors shows low initial contact resistance of less than 10 m/spl Omega/ when bulk conductor material is minimized in the measurement scheme. Stability is typically determined to be less than a 5-10 m/spl Omega/ change as a function of stress. The main intent of this study is to characterize the electrical contact resistance performance of joints made with isotropic electrically conductive adhesives. A copper comb pattern test vehicle was designed and fabricated using 0.25-mm thick lead frame material. The plating finishes that were applied to the copper substrate included a palladium alloy, gold, tin, and nickel. Test samples were made with several electrically conductive adhesives. Samples consisted of two comb patterns bonded to each other making a gang of 40 lap joints. Variables from circuit packaging such as coefficient of thermal expansion mismatches are purposely avoided in this study. Contact resistance measurements were made initially and as a function of time during environmental tests. Stresses included thermal cycling, thermal aging, and temperature and humidity conditioning. The stability of electrical contact resistance is shown to be influenced by both plating metallurgy and the conductive adhesive itself. Contact resistance equivalent to solder is possible with some electrically conductive adhesives on appropriate metallurgical finishes. Mechanically, adhesive joints are less robust than solder joints, and therefore care must be taken to eliminate or minimize the effects of mechanical loading. >