cssi/SciSciGPT-SciSciNet huggingface dataset:
Second-Best Prioritization of Environmental Cleanups

Yearly allocations to EPA Superfund cleanups are relatively fixed, but the EPA has significant leeway over which sites to clean within a given year. However, the EPA currently does not consider any economic criteria when ordering sites for remediation. Given the local economic benefits to cleaning, the EPA may be able to increase overall social welfare by considering certain economic criteria. We build a theoretical model that incorporates both the short-run and long-run cleanup benefits and identifies the site and location characteristics that impact welfare. We then use calibrated Monte Carlo simulations to compare 6 feasible cleanup policies and 1 infeasible best-case policy to the status quo policy. We find that the best of the feasible policies can on average improve welfare by 1.88% of the status quo policy, though the administrative costs are likely non-trivial. A similarly beneficial alternative may be to use a set of heuristics regarding site characteristics to order cleanups. In order of importance, the ranking criteria are: site cleanup cost (cheapest first), long-term economic damages from waste, areas currently in a recession, and local discount rates. Ex ante local economic stability has no significant effect. This set of heuristics sees a slightly smaller mean welfare increase (1.85%). Notably, since 3 of the 4 criteria are easily observable, this increase is nearly costless.
Factors influencing adherence to an app-based exercise program in adolescents with painful hyperkyphosis.

Software applications (apps) could potentially promote exercise adherence. However, it is unclear whether adolescents with painful hyperkyphosis will use an app designed for a home exercise program. The purpose of this study is to assess factors regarding adherence to an app-based home exercise program in adolescents with hyperkyphosis and back pain who were provided a one-time exercise treatment. Twenty-one participants were instructed in a one-time exercise treatment and asked to complete a home exercise program 3 times a week for 6 months using an app called PT PAL. At a 6-month follow-up, 14 participants completed a survey assessing factors related to their experiences using the app and their treatment engagement. Although most participants did not use the app, they reported performing their exercises a few times per week. The adolescent participants considered the app to be more of a barrier than a supportive measure for promoting exercise adherence. Most participants still reported bothersome back pain. Although adherence to the 6-month app-based home exercise program was not successful, adolescents still viewed technology support such as text reminders as a potential solution. ClinicalTrials.gov Identifier: NCT03212664 . Registered 11 July 2017. Retrospectively registered.
Color Centers in Mg F 2

The effects of radiation temperature and intensity on the colorability of Mg${\mathrm{F}}_{2}$ single crystals obtained from various commercial sources were investigated. The results show that the radiation-damage process in Mg${\mathrm{F}}_{2}$ is photochemical in nature and strikingly similar to that in the alkali halides. In the past it has been proposed that long-range focusing events are, in part, responsible for the photochemical coloration of the alkali halides. However, in Mg${\mathrm{F}}_{2}$ there are no obvious long-range focusing directions, and the data suggest that such a process is not necessary for the production of photochemical damage. The radiation equilibrium observed to prevail between $F$ and $M$ centers in KCl is also evident in Mg${\mathrm{F}}_{2}$, and this effect was used to propose that absorption bands at 370 and 400 nm are due to $M$ centers.
Landscape genetics of the foundational salt marsh plant species black needlerush ( Juncus roemerianus Scheele) across the northeastern Gulf of Mexico

Common species important for ecosystem restoration stand to lose as much genetic diversity from anthropogenic habitat fragmentation and climate change as rare species, but are rarely studied. Salt marshes, valuable ecosystems in widespread decline due to human development, are dominated by the foundational plant species black needlerush (Juncus roemerianus Scheele) in the northeastern Gulf of Mexico. We assessed genetic patterns in J. roemerianus by measuring genetic and genotypic diversity, and characterizing population structure. We examined population connectivity by delineating possible dispersal corridors, and identified landscape factors influencing population connectivity. A panel of 19 microsatellite markers was used to genotype 576 samples from ten sites across the northeastern Gulf of Mexico from the Grand Bay National Estuarine Research Reserve (NERR) to the Apalachicola NERR. Genetic distances (FST and Dch) were used in a least cost transect analysis (LCTA) within a hierarchical model selection framework. Genetic and genotypic diversity results were higher than expected based on life history literature, and samples structured into two large, admixed genetic clusters across the study area, indicating sexual reproduction may not be as rare as predicted in this clonal macrophyte. Digitized coastal transects buffered by 500 m may represent possible dispersal corridors, and developed land may significantly impede population connectivity in J. roemerianus. Results have important implications for coastal restoration and management that seek to preserve adaptive potential by sustaining natural levels of genetic diversity and conserving population connectivity. Our methodology could be applied to other common, widespread and understudied species.
On-line Bayesian-based Model-set Management Method with Case Study of Steam Reforming Prediction under Various Feed Compositions

Abstract Steam reforming is the most widespread process for the generation of hydrogen-rich synthesis gas from light carbohydrates. One of the operation and design challenges is that the feed materials are various from natural gas, shale gas, to liquid gas, or naphtha. The optimal operating conditions identified under one type of feed may not be functional well under another one. Even within the same type feed, the compositions may vary large enough in continuous operation that requires online operating conditions tuning. Currently, two types of control strategies are applied to address the issue: one is feedforward control that the feed composition is measured in advance so that the operating conditions could be set accordingly. However, the performance would rely on the accuracy of the process model, and may not be robust on feed composition disturbances. The other is simple PID feedback control that the conditions are adjusted by the product composition feedback. However, the complexity of the multi-input multi-output (MIMO) steam reforming may bring challenges to the PID controller design. In this paper, a Bayesian-based model-set management method is introduced for constructing a statistically superior model set for online model-based control application. First, a number of steam reforming models are developed on various feed types or compositions. Then the optimal operating conditions are identified on the weighted model predictions. During online application, the measured product compositions are feedback to adjust the weights by a Bayesian-based statistical method. A repeated use of the method keeps the weights updated constantly based on the newly available system data, which makes the model-set-based prediction more precise, robust, and adaptive to various feeds automatically. The efficiency of the method is demonstrated by studying a steam reforming system with different feeds.
Conclusions and Further Work

There has been significant interest in radical pair reactions for a number of years [1, 2, 3, 4, 5], due to their relevance to a number of biological and technological systems [6, 7, 8, 9, 10, 11]. In particular, the effect of magnetic fields on radical pair reactions has been widely studied [12, 13, 14, 15, 16], with even very weak magnetic interactions able to dramatically change the rate and yield of a reaction [17, 18]. In this thesis, we have developed both quantum mechanical and semiclassical methods of simulating radical pair reactions, and then applied those methods to three real systems in order to obtain some physical insight into their behaviour. Here we shall summarise our findings, before suggesting two areas for further work where the application of the semiclassical theory introduced in Sect. 3.1 has shown promising early results.
Rotational Control Method with Transformer Loss Savings in Solid-State Transformer based Converter System

This paper presents a novel control strategy for high-frequency transformer loss reduction in modular solid-state transformer (SST) based converter system. The modular SST design is based on an ac-dc power-electronic building block (PEBB) comprised of an H-bridge at the AC input and a bi-directional soft-switching isolated dc-dc converter with a high frequency transformer. The AC terminals of input H-bridges are connected in series and directly coupled to the AC line, while the output DC terminals are all connected in parallel at low voltage. The key innovation described in the paper is the control scheme that reduces core and winding losses associated with the dc-dc resonant stage by turning off the selected dc-dc converters in synchronism with the line voltage. The prototype for test described in this paper is based on a modular SST where each module is rated at 50 kVA, with a 200 kHz transformer using 1.7 kV SiC MOSFETs, but the described control concepts are more broadly applicable to similar topologies.
PROGNOSTIC UTILITY OF A MODIFIED HEART SCORE WHEN DIFFERENT TROPONIN CUT-POINTS ARE USED

Although the recommended cut-point for cardiac troponin (cTn) is the 99th%, many institutions use cut-points that are multiples higher than the 99th%. Prior studies have shown that patients with a HEART Score (HS) ≤ 3 and normal serial cTn values (modified HS) are at low risk for adverse events.
Evaluation of the Psychometric Properties of the Teacher Efficacy for Promoting Partnership Measure Among a Sample of Head Start Educators

The current study reports the evidence for the reliability (via coefficient α, coefficient ω) and validity (via confirmatory factor analysis, correlations) of the Teacher Efficacy for Promoting Par...
HUGHES STOVIN SYNDROME: A RARE FORM OF BEHCET’S DISEASE PRESENTING AS RECURRENT INTRACARDIAC THROMBI

Hughes Stovin syndrome (HSS) is very rare, believed to be a cardiovascular variant of Behcet's disease, characterized by an association of multiple pulmonary artery aneurysms and peripheral venous thrombosis. Intracardiac thrombi is a rare presentation, found in 6 patients among the 38 case reports
Association of Category of Cattle Exposure with Tuberculosis Knowledge among Dairy Workers in Bailey County, Texas.

Objective: To determine the knowledge of tuberculosis (TB) among dairy workers in Bailey County, Texas. Methods: A cross-sectional study design was used to collect 225 survey responses concerning knowledge of TB among dairy workers on 10 dairy farms in Bailey County, Texas. Subjects used iPad tablets to log responses to 15 demographic questions and a 17-item TB knowledge quiz, measured by: (1) TB characteristics, (2) TB transmission, (3) TB symptoms, (4) TB diagnosis, (5) TB treatment, and (6) bovine TB. A proxy for exposure, dairy workers were classified into categories of cattle exposure - high, medium, and low. Results: Relative to the medium/low group, workers in the high group tended to be younger (32.6 (SD 11.0)), Guatemalan (52.6%), K'iche' speaking (37.8%), males (89.1%) with less years living in the U.S. (10.8 [SD 12.5]) and lower levels of formal education completed (59.6% with no formal/elementary level). Overall, the average score was 7.1 (SD 4.9) out of 17 (41.8% out of 100.0%). Relative to one another, the medium/low group (8.0 (SD 4.6) out of 17) scored better than the high group (6.7 [SD 5.1] out of 17). No significant associations were found between the category of exposure and TB knowledge score. Conclusion: Deficiencies in TB knowledge were identified in all categories of exposure. TB training on dairy farms should include all measured tested in this study and should be administered to all workers regardless of the category of exposure.
On the two-potential constitutive modeling of dielectric elastomers

This work lays out the two-potential framework for the constitutive modeling of dielectric elastomers. After its general presentation, where the constraints imposed by even electromechanical coupling, material frame indifference, material symmetry, and entropy imbalance are all spelled out, the framework is utilized to put forth a specific constitutive model for the prominent class of isotropic incompressible dielectric elastomers. The model accounts for the non-Gaussian elasticity and electrostriction typical of such materials, as well as for their deformation-enhanced shear thinning due to viscous dissipation and their time-dependent polarization due to electric dissipation. The key theoretical and practical features of the model are discussed, with special emphasis on its specialization in the limit of small deformations and moderate electric fields. The last part of this paper is devoted to the deployment of the model to fully describe the electromechanical behavior of a commercially significant dielectric elastomer, namely, the acrylate elastomer VHB 4910 from 3M.
PREDICTING Lyα AND Mg II FLUXES FROM K AND M DWARFS USING GALAXY EVOLUTION EXPLORER ULTRAVIOLET PHOTOMETRY

A star's ultraviolet (UV) emission can greatly affect the atmospheric chemistry and physical properties of closely orbiting planets with the potential for severe mass loss. In particular, the Lyα emission line at 1216 A, which dominates the far-ultraviolet (FUV) spectrum, is a major source of photodissociation of important atmospheric molecules such as water and methane. The intrinsic flux of Lyα, however, cannot be directly measured due to the absorption of neutral hydrogen in the interstellar medium and contamination by geocoronal emission. To date, reconstruction of the intrinsic Lyα line based on Hubble Space Telescope spectra has been accomplished for 46 FGKM nearby stars, 28 of which have also been observed by the Galaxy Evolution Explorer (GALEX). Our investigation provides a correlation between published intrinsic Lyα and GALEX far- and near-ultraviolet (NUV) chromospheric fluxes for K and M stars. The negative correlations between the ratio of the Lyα to the GALEX fluxes reveal how the relative strength of Lyα compared to the broadband fluxes weakens as the FUV and NUV excess flux increase. We also correlate GALEX fluxes with the strong NUV Mg II h+k spectral emission lines formed at lower chromospheric temperatures than Lyα. The reported correlations provide estimates ofmore » intrinsic Lyα and Mg II fluxes for the thousands of K and M stars in the archived GALEX all-sky surveys. These will constrain new stellar upper atmosphere models for cool stars and provide realistic inputs to models describing exoplanetary photochemistry and atmospheric evolution in the absence of UV spectroscopy.« less
Design and Implementation of a Tool to Assess Students’ Understanding of Metabolic Pathways Dynamics and Regulation

This article describes a biochemistry educator community-driven effort to design and implement a course-based instrument to assess undergraduate students’ understanding of metabolic pathway dynamic...
Radiative corrections for factorized jet observables in heavy ion collisions

I look at the renormalization of the medium structure function and a medium induced jet function in a factorized cross section for jet substructure observables in Heavy Ion collisions. This is based on the formalism developed in \cite{Vaidya:2020lih}, which uses an Open quantum system approach combined with the Effective Field Theory(EFT) for forward scattering to derive a factorization formula for jet observables which work as hard probes of a long lived dilute Quark Gluon Plasma(QGP) medium. I show that the universal medium structure function that captures the observable independent physics of the QGP has both UV and rapidity anomalous dimensions that appear due to medium induced Bremsstrahlung. The resulting Renormalization Group(RG) equations correspond to the BFKL equation and the running of the QCD coupling respectively. I present the first results for the numerical impact of resummation using these RG equations on the mean free path of the jet in the medium. I also briefly discuss the prospects of extending this formalism for a short lived dense medium.
Amino Acids in Cell Signaling: Regulation and Function

Amino acids are the main building blocks for life. Aside from their roles in composing proteins, functional amino acids and their metabolites play regulatory roles in key metabolic cascades, gene expressions, and cell-to-cell communication via a variety of cell signaling pathways. These metabolic networks are necessary for maintenance, growth, reproduction, and immunity in humans and animals. These amino acids include, but are not limited to, arginine, glutamine, glutamate, glycine, leucine, proline, and tryptophan. We will discuss these functional amino acids in cell signaling pathways in mammals with a particular emphasis on mTORC1, AMPK, and MAPK pathways for protein synthesis, nutrient sensing, and anti-inflammatory responses, as well as cell survival, growth, and development.
MLED: A Layered Architecture for Reducing Undetected Error Probability in File Transfer

Reliability in petabyte-scale file transfers is critical for data collected from scientific instruments. We introduce a Multi-Layer Error Detection (MLED) architecture that significantly reduces the Undetected Error Probability (UEP) in file transfer. MLED is parameterized by a number of layers $n$ , and a policy $P_{i}$ for each layer $1 \le i \le n$ that describes its operation. MLED generalizes existing error detection approaches used in file transfer. We show conditions under which MLED reduces UEP. Analytical results show that a petabyte-size file transfer in MLED with $n=2$ using CRC-32s improves UEP by $2.49E\,+\,28$ compared to a single-layer CRC-64, when the BER is 10−10.
Design applications of compact MOSFET model for extended temperature range (60-400K)

An advanced MOSFET model for the 60–400 K temperature range is developed starting with the industry standard PSP model. The new model is experimentally verified, implemented in a commonly used circuit simulator and tested for convergence. This provides a robust and accurate description of low temperature MOSFET characteristics, including analogue performance. Simulations on a switched-capacitor integrator design are performed to illustrate the capabilities of the new model and to justify a new design methodology for the extended temperature range.
Steganography with Imperfect Samplers.

The goal of steganography is to pass secret messages by disguising them as innocent-looking covertexts. Real world stegosystems are often broken because they make invalid assumptions about the system’s ability to sample covertexts. We examine whether it is possible to weaken this assumption. By modeling the covertext distribution as a stateful Markov process, we create a sliding scale between real world and provably secure stegosystems. We also show that insufficient knowledge of past states can have catastrophic results.
Energy and timing characterization of VLSI charge-pump phase-locked loops

Phased locked loops (PLLs) are frequently employed in high-speed communication links, RF demodulation systems and SOCs for frequency synthesis. As wireless portable systems become standard, performance and power PLL models are essential in order to explore design trade-offs and feasible power reductions. We present a PLL timing model, review results of our power model and couple them with expressions for jitter estimation. The model has been validated and shown to be within 5% of circuit level simulation numbers.
Chapter 4 The Pyridine Alkaloids

Publisher Summary Two facts concerning tobacco are significant. Although growing tobacco was restricted in Europe and Asia by the need for food crops, the world production for the season 1945-46 was estimated at 6,654,000,000 lbs. One of the factors forcing the economics of Britain into an unfavorable position is the import of tobacco into that country from the dollar areas. These two facts clearly illustrate that at least one of the pryidine alkaloids occupies a unique position of economic and industrial importance, commensurate with its theoretical interest. There are isolated instances where the parent bases, pyridine and piperidine, have been found to occur in nature. However, it is the more complex members of this series of bases that have attracted the attention of alkaloid chemists. The distribution of the more complex pyridine alkaloids in the plant kingdom is more widespread. In this chapter, the various groups of alkaloids are classified according to the position of the substituents and the degree of substitution in the pyridine nucleus (the term “pyridine” is used loosely in this classification scheme to include also those alkaloids with a piperidine nucleus) of the index compound or main member of each group of alkaloids.
Matching and record linkage

This overview gives background on a number of statistical methods that have been proven effective for record linkage. To prepare data for the main computational algorithms, we need parsing/standardization that allows us to structure the free-form names, addresses, and other fields into corresponding components. The main parameter-estimation methods are unsupervised methods that yield 'optimal' record linkage parameters. Extended methods provide estimates of false match rates in both unsupervised and, with greater accuracy, in semi-supervised situations. Finally, the paper describes ongoing research for adjusting standard statistical analyses for linkage error. WIREs Comput Stat 2014, 6:313-325. doi: 10.1002/wics.1317
Verbal Aspect and the Greek Future: ἕξω and σχήσω

The verb ἔχω has two future formations, ἕξω and σχήσω. Opinion is divided, however, as to whether there is any semantic difference between them. In the view of some, ἕξω shows imperfective aspect (‘will have, keep’), σχήσω perfective aspect (‘will hold back, prevent’). Others deny that any such aspectual distinction can be drawn, pointing to passages where the supposedly aoristic σχήσω is clearly durative. Examination of the evidence from seven authors reveals that, despite the decline of the (-)σχησ- future, the two forms are nearly always used in distinct ways, which can often be characterized as aspectual. First, the (-)σχησ- future is used more often of telic events. Second, it is preferred when the verb has the meaning ‘prevent’, especially when it has a prepositional prefix; as this sense shows higher transitivity than the ‘have’ semantics of the (-)ἑξ- future, it is reasonable to associate it with the perfective aspect.
Foster Parent Satisfaction: Differences by Gender

In this study, we examine the different mechanisms that lead to satisfaction with fosterparenting for men and women. We use a dataset of foster parents in Ohio in 1993 andanalyze the data using Structural Equation Modeling (SEM). We find that men are moreinfluenced by feelings of efficacy and possibly experience, whereas women are moreinfluenced by the social worker and feelings of competence. These different mechanismsimply different role identification and different treatment by a social worker for men andwomen.
Toward an Animal Model of Gambling: Delay Discounting and the Allure of Unpredictable Outcomes

Laboratory investigations of gambling are sometimes criticized as lacking ecological validity because the stakes wagered by human subjects are not real or no real monetary losses are experienced. These problems may be partially addressed by studying gambling in laboratory animals. Toward this end, data are summarized which demonstrate that laboratory animals will work substantially harder and prefer to work under gambling-like schedules of reinforcement in which the number of responses per win is unpredictable. These findings are consistent with a delay discounting model of gambling which holds that rewards obtained following unpredictable delays are more valuable than rewards obtained following predictable delays. According to the delay discounting model, individuals that discount delayed rewards at a high rate (like pathological gamblers) perceive unpredictably delayed rewards to be of substantially greater value than predictable rewards. The reviewed findings and empirical model support the utility of studying animal behavior as an ecologically valid first-approximation of human gambling.
Bond dissociations in hypervalent ammonium radicals prepared by collisional neutralization of protonated six‐membered nitrogen heterocycles

Hypervalent organic ammonium radicals were generated by collisional neutralization with dimethyl disulfide of protonated 1,4-diazabicyclo[2.2.2]octane (1H+), N,N′-dimethylpiperazine (2H+) and N-methylpiperazine (3H+). The radicals dissociated completely on the 5.1 μs time-scale. Radical 1H• underwent competitive N−H and N−C bond dissociations producing 1,4-diazabicyclo[2.2.2]octane and small ring fragments. Dissociations of radical 2H• proceeded by N−H bond dissociation and ring cleavage, whereas N−CH3 bond cleavage was less frequent. Radical 3H• underwent N−H, N−CH3 and N−Cring bond cleavages followed by post-reionization dissociations of the formed cations. The pattern of bond dissociations in the hypervalent ammonium radicals derived from six-membered nitrogen heterocycles is similar to those of aliphatic ammonium radicals. © 1997 John Wiley & Sons, Ltd.
Intra-cavity absorption spectroscopy with narrow-ridge microfluidic quantum cascade lasers.

We demonstrate microfluidic laser intra-cavity absorption spectroscopy with mid-infrared λ≈9µm quantum cascade lasers. A deep-etched narrow ridge waveguide laser is placed in a microfluidic chamber. The evanescent tails of the laser mode penetrate into a liquid on both sides of the ridge. The absorption lines of the liquid modify the laser waveguide loss, resulting in significant changes in the laser emission spectrum and the threshold current. A volume of liquid as small as ~10pL may, in principle, be sufficient for sensing using the proposed technique. This method, similar to the related gas-phase technique, shows promise as a sensitive means of detecting chemicals in small volumes of solutions.
Proving Properties of Complex Data Structures

This paper is concerned with proving properties of programs which use data structures. The goal is to be able to prove that all instances of a class (e.g. as defined in Simula) satisfy some property. A method of proof which achieves this goal, generator induction, is studied and compared to other proof rules and methods: inductive assertions, recursion induction, computation induction, and, in some detail, structural induction. The paper concludes by using generator induction to prove a characteristic property of an implementation of hashtables.
A Test of the Air-Seeding Hypothesis Using Sphagnum Hyalocysts

“Air-seeding” is a proposed mechanism for the initiation of water stress embolism in dead plant cells. During air-seeding, external air is drawn into the lumen of a dead plant cell through a pore or crack in the cell wall. The resulting bubble may expand to fill the lumen, thus embolizing the cell. The data presented confirm that Sphagnum hyalocysts can embolize by air-seeding when the pressure difference across the air-water meniscus is given by ΔP = 0.3/D (derived from the capillary equation), where ΔP is the pressure difference across the meniscus (megapascal), and D is the diameter (micrometer) of the pore through which the air bubble enters.
Modeling of a Partial-Flow, Diesel, Lean NOx Trap Systems

Lean NOx Traps (LNTs) have shown promise for Diesel applications; however, production implementation in vehicles poses a number of challenges. Much of the literature reports on LNT systems in which the catalyst always receives the full flow of exhaust from the engine, referred here as full-flow regeneration systems. Another implementation of the LNT is one in which the exhaust can be partially or fully diverted from the catalyst to allow local introduction of the necessary reductants for regeneration. The physical aspects of one such system, as well as a control-oriented model are presented with experimental validation. In the system described here, the exhaust flow is diverted around the catalyst during regenerations. In the low exhaust flow through the catalyst, reductant is added (Diesel fuel typically) which provides the rich conditions for regenerating the trap. This allows the engine to continue to run in normal lean mode, which overcomes one of the major challenges for full-flow regeneration systems. Successful regeneration with liquid Diesel fuel is strongly dependent on catalyst temperature, which is addressed by proper thermal management of the system through the addition of fuel prior to regeneration. In this paper, both component level and vehicle level simulations are presented in terms of fuel economy versus NOx reduction. Several different system configurations and control strategies are compared.Copyright © 2005 by ASME
Pathogenesis of craniofacial and body wall malformations induced by ochratoxin A in mice

Ochratoxin A (OA), a mycotoxin commonly found in soils and on moldy food such as cereal grains, is a potent teratogen. The present investigation was designed to examine the teratogenicity of OA administered acutely at early post-implantation stages in mice, with particular emphasis on the pathogenetic basis of induced malformations. Maternal OA administration on gestational day (GD) 7 or 8 resulted in excessive cell death in selected cell populations. After a single dose of 2–4 mg/kg, excessive amounts of cell death was notable within 6 hours, and persisted to 36 hours post-treatment. As observed in GD 14 or 18 fetuses, the spectrum of induced craniofacial malformations included exencephaly, midfacial clefting, cleft lip, as well as hypotelorism, and synophthalmia associated with holoprosencephaly. Body wall defects involved either the abdominal wall alone, or in combination with the thoracic wall, resulting in partial or complete exposure of the viscera. Potential mechanisms for OA-induced selective cell killing are discussed. © 1993 Wiley-Liss, Inc.
Lyme borreliosis spirochete Erp proteins, their known host ligands, and potential roles in mammalian infection

Lyme borreliae naturally maintain numerous distinct DNA elements of the cp32 family, each of which carries a mono- or bicistronic erp locus. The encoded Erp proteins are surface-exposed outer membrane lipoproteins that are produced at high levels during mammalian infection but largely repressed during colonization of vector ticks. Recent studies have revealed that some Erp proteins can serve as bacterial adhesins, binding host proteins such as the complement regulator factor H and the extracellular matrix component laminin. These results suggest that Erp proteins play roles in multiple aspects of mammalian infection.
Effects of angiotensin II receptor blockade on remnant glomerular permselectivity

This study examined the mechanisms by which angiotensin II (Ang II) receptor blockade improves glomerular barrier function in rats with reduced nephron number. Proteinuria was measured at four weeks after 5/6 renal ablation, and rats were then divided into a group which received the Ang II receptor blocker MK954 and a group which received no treatment. Studies performed one week later showed that Ang II receptor blockade reduced proteinuria without altering GFR in renal ablated rats. Micropuncture studies showed that Ang II blockade reduced both mean arterial pressure (142 +/- 7 mm Hg, ablation without treatment; 105 +/- 2 mm Hg, ablation with treatment) and glomerular transcapillary pressure (54 +/- 3 mm Hg, ablation without treatment; 43 +/- 1 mm Hg, ablation with treatment). Dextran sieving studies showed that untreated rats developed a size-selective defect characterized by increased transglomerular passage of neutral dextrans with radii 54 to 76 A and a charge-selective defect characterized by an increased transglomerular passage of anionic dextran sulfate with a radius of approximately 18 A. Ang II blockade reduced fractional clearance values for large neutral dextrans near to values observed in normal rats but had no effect on the fractional clearance of dextran sulfate (0.68 +/- 0.11, ablation without treatment; 0.66 +/- 0.08, ablation with treatment; 0.46 +/- 0.05, normal rats). These findings indicate that reducing Ang II activity improves size-selectivity without affecting charge-selectivity in injured remnant glomeruli.
On the similarity of functional connectivity between neurons estimated across timescales.

A central objective in neuroscience is to understand how neurons interact. Such functional interactions have been estimated using signals recorded with different techniques and, consequently, different temporal resolutions. For example, spike data often have sub-millisecond resolution while some imaging techniques may have a resolution of many seconds. Here we use multi-electrode spike recordings to ask how similar functional connectivity inferred from slower timescale signals is to the one inferred from fast timescale signals. We find that functional connectivity is relatively robust to low-pass filtering—dropping by about 10% when low pass filtering at 10 hz and about 50% when low pass filtering down to about 1 Hz—and that estimates are robust to high levels of additive noise. Moreover, there is a weak correlation for physiological filters such as hemodynamic or Ca2+ impulse responses and filters based on local field potentials. We address the origin of these correlations using simulation techniques and find evidence that the similarity between functional connectivity estimated across timescales is due to processes that do not depend on fast pair-wise interactions alone. Rather, it appears that connectivity on multiple timescales or common-input related to stimuli or movement drives the observed correlations. Despite this qualification, our results suggest that techniques with intermediate temporal resolution may yield good estimates of the functional connections between individual neurons.
Intrauterine nutrition and aggression

WITH the increase in conflict and aggression in human society, the underlying causes of aggression take on added significance. The laboratory investigation of human aggression is difficult primarily because of ethical considerations. Animal aggression must therefore serve as a model for the experimental study of suspected causes of aggression. One potential cause is malnutrition, which has been assessed by studies of the effects of prenatal zinc deficiency and intra-uterine undernutrition on aggressive behaviour in the adult rat. Prenatal zinc deficiency was chosen because it has been found to significantly reduce the size of the brains of foetal1 and neonatal rats2, to impair the synthesis of DNA in the rat brain3, and to decrease the activity of RNA polymerase in neonatal rat liver4 and brain5. When zinc deficiency is very severe an increased incidence of central nervous system teratology occurs in the foetal rat6. Behavioural deficits such as impaired avoidance learning have also been observed1,7.
Employee-rated job demands: Implications for prevention of occupational back injuries

This paper describes the application of the ability requirements approach to study the relationship between back injuries and job demands. The procedure used groups of active workers to construct profiles of job demands by rating physical abilities needed to perform various tasks in the job. Environmental demands were similarly rated. Profiles were developed for 25 high injury rate jobs in a mass transit company. Worker ratings of job demands were correlated with back injury rates. The results confirm that back injuries are associated with physical effort or work conditions in some jobs. Several abilities formed a single factor of physical effort while the present inventory of work conditions did not. A multidimensional job description of physical effort, environmental and organizational factors is proposed to explain adequately occupational back injuries in the public transportation, construction and utilities.
Review of analytical measurements facilitated by drop formation technology

The use of drops in chemical analysis methodology and instrumentation has a deeply rooted past in the area of electrochemistry through the evolution of the dropping mercury electrode (DME). This history has also been deeply rooted in the field of surface science due to the inextricable connection between surface tension forces and drop formation. While the use of the DME is well established, the evolution of drop-based analytical measurements using aqueous and/or organic drops is a rapidly emerging and diverse field, encompassing several interdisciplinary areas of science: surface science and interfacial surface tension phenomena, spectroscopic detection, analytical instrumentation hyphenation, liquid membrane separation, reagent chemistry, electrochemistry, and so on. This review of 112 references covers various aspects of drop-based analytical measurements involving aqueous and/or organic drops. The review is divided into four sections, although the classification of a particular reference into a given section can sometimes be argued. The first section considers the use of drops as a detector component. The second section deals with fundamental studies that probe drop-related chemical and physical phenomena that are relevant to current and future developments in analytical chemistry. The next section covers recent advances in the area of microfluidic sample handling and instrumentation hyphenation. The final section reports upon emerging technologies aimed toward drop-based chemical analyzers that incorporate a number of steps in a chemical analysis: microextraction, preconcentration, reagent chemistry, microfluidic handling, and detection.
Sex differences in defence of eggs and nestlings by northern mockingbirds, Mimus polyglottos

Abstract Northern mockingbirds, Mimus polyglottos, actively defended eggs and nestlings from humans visiting nests. There was a significant positive correlation between levels of defence by mates within pairs. Pairs in which males strongly attacked intruders displayed greater nesting success than pairs in which males did not. By several measures, males defended offspring more than females did: males approached closer when defending nestlings but not eggs, and engaged in more attacks on the intruder during both egg and nestling stages. Males, but not females, increased their frequency of attacks from the egg to the nestling stage. More males than females struck the intruder when defending nestlings. When defending nestlings, males followed the intruder to the edge of the territory more often than did the females and vocalized more frequently during encounters with intruders. Both sexes hovered over the intruder infrequently during the egg stage. During the nestling stage, males hovered more than females, but the sexes hovered at similar distances overhead. Birds tending to hover over the intruder were mated to birds that likewise hovered. Males, but not females, approached intruders more closely as nestlings aged. A decrease in the distance of approach to the intruder with age of the eggs was related to nest revisitation. A similar decrease in distance of approach with the ageing of nestlings was not explained as a nest revisitation effect. A male-biased sex ratio of adults in this population may favour the condition where males defend offspring more strongly than do females.
Functional aspects of the retina relating to infrared focal plane arrays

Research of vertebrate and invertebrate vision systems has revealed them to be remarkable assemblies of simple cells performing collectively various image processing and analysis tasks. Among these are counted edge enhancement, noise suppression, dynamic range compression, and motion and object orientation detection. These functions are achieved due to the massively parallel structure of these systems and appropriate non-linear inter-cell interactions, among them lateral inhibition. The high degree of connectivity existent in the vertebrate retina is currently beyond reach of integrated implementations; however, even its approximations applied to focal plane arrays can result in enhanced and more sophisticated performance. These approximations are discussed mathematically by means of methods developed for analysis of neural networks. A photoreceptor lateral interaction network, Grossberg's shunting neural network, and a novel modified version of the latter are compared in their effect on spatial nonuniformity noise and edge enhancement. These two qualities are of special interest in the case of infrared imaging. The modified shunting network combines an adaptive lateral signal spread amongst photodetectors with non-linear, multiplicative lateral inhibition. The first effect serves to reduce the effects of spatial noise, while the second, by its differentiating nature, removes low spatial frequencies and enhances high spatial frequency components inherent to the image.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Fc intermediate (Fci), a papain-generated fragment of human IgG, intermediate in charge, molecular weight and cleavage between the Fc and Fc' fragments of IgG

Fc intermediate (Fci) is a papain-generated fragment of human IgG which is intermediate in charge, mol. wt and state of cleavage between the Fc and Fc' fragments of IgG. It is composed of two polypeptide chains of unequal mol. wt held together by non-covalent bonds between the C gamma 3 regions. The larger polypeptide chain has both a C gamma 2 and C gamma 3 domain and its N-terminus is at Leu 235 (60%) and Leu 234 (40%) (IgGl Eu numbering). The smaller polypeptide chain is composed of a C gamma 3 domain with its N-terminus at Gly 341. The carboxy-termini obtained by carboxypeptidase digestion and by a computer program which determined the most probable sequences by fitting the amino acid compositions to the sequence of IgG Eu Fc were heterogeneous involving residues 440-446 for the large polypeptide chain and 429-436 for the small one. The calculated mol. wt of the large polypeptide chain was 26,183, assuming the N-terminus at Leu 234 and C-terminus at 446 and including the carbohydrate moiety. The calculated mol. wt for the small polypeptide chain was 10,682, with the N-terminus at 341 and assuming the C-terminus at 434, for a combined mol. wt of 36,865 for the Fci fragment. Sedimentation equilibrium ultracentrifugation of Fci under non-dissociating conditions showed an Mn of 36,200 +/- 1200, an Mw of 36,400 +/- 600 and an Mz of 37,000 +/- 300 g/mole. The best yields of Fc were obtained with a 6-hr digestion and the best yields of Fcl and Fc' were obtained with digestion for 18 hr in phosphate buffer. Digestion in Tris buffer for 18 hr gave results similar to the 18-hr digestion in phosphate buffer except the yields of Fc' were less. This fragment may be useful for exploring biological functions of human IgG Fc. In addition, some Fc fragments obtained by papain digestion of human IgG either in phosphate or Tris buffer are not covalently bonded and are probably cleaved on the carboxy-terminal side of the interchain disulfide bonds at Leu 234 or Leu 235, the N-termini for the large polypeptide chain of Fci. This indicates that, if disulfide bonded Fc fragments are needed, gel filtration under dissociating conditions will be necessary to remove non-covalently bonded Fc.
A forced-choice study of edge detectors in the human visual system*

Psychophysical studies using masking procedures to investigate the possible existence of edge detectors in the human visual system have typically been flawed by methodological errors and omissions that make their findings uninterpretable. An example of such a study is given and evaluated, and a replication of that study, using a spatial forced-choice methodology, is reported in detail. The results of this replication are shown to contradict the critical findings of the earlier study; furthermore, it is suggested that any ambiguities in the results of this replication can be interpreted in terms of methodological and procedural factors, rather than in terms of higher-order neurological constructs. Finally, a further test of this methodological interpretation is proposed.
Global achievements in sustainable land management

Identification and development of sustainable land management is urgently required because of widespread resource degradation from poor land use practices. In addition, the world will need to increase food production to meet the nutritional needs of a growing global population without major environmental degradation. Ongoing climate change and its impacts on the environment is an additional factor to consider in identifying and developing sustainable land use practices. The objectives of this paper are to: (1) provide a background to the need for sustainable land management, (2) identify some of its major components, and (3) discuss some examples of sustainable land management systems that are being practiced around the world. Some common components of this type of management are: (1) understanding the ecology of land management, (2) maintenance or enhancement of land productivity, (3) maintenance of soil quality, (4) increased diversity for higher stability and resilience, (5) provision of economic and ecosystem service benefits for communities, and (6) social acceptability. Several examples of sustainable land management systems are discussed to illustrate the wide range of systems that have been developed around the world including agroforestry, conservation agriculture, and precision agricultural systems. Improved technology, allowing for geater environmental measurement and for improved access and sharing of information, provides opportunities to identify and develop more sustainable land management practices and systems for the future.
Approximate Circular and Straight-Line Path Generation With High-Performance Function-Generating Linkages

Generation de trajectoires approximativement lineaire ou circulaire a l'aide de mecanismes generateurs de fonction hautement performants
Epidemiology of Viral Hepatitis and Hepatocellular Carcinoma

Most cases of hepatocellular carcinoma (HCC) are associated with cirrhosis related to chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infection. Changes in the time trends of HCC and most variations in its age-, sex-, and race-specific rates among different regions are likely to be related to differences in hepatitis viruses that are most prevalent in a population, the timing of their spread, and the ages of the individuals the viruses infect. Environmental, host genetic, and viral factors can affect the risk of HCC in individuals with HBV or HCV infection. This review summarizes the risk factors for HCC among HBV- or HCV-infected individuals, based on findings from epidemiologic studies and meta-analyses, as well as determinants of patient outcome and the HCC disease burden, globally and in the United States.
Nonlinear Tracking Controllers Design

In this paper we present a new technique for design of nonlinear feedback controllers that yield satisfactory tracking performance for a class of dynamic systems. The controller is based on minimization of predicted tracking errors. Some tracking convergence properties of the controller are established. In the face of model uncertainties, we show that the unique structure of the controller allows robust stable tracking via high-gain feedback. Possible modifications for adaptive control in the presence of parameter uncertainties are discussed. Practical usefulness and effectiveness of the approach are exemplified by an autopilot design problem for a missile.