cssi/SciSciGPT-SciSciNet huggingface dataset:
Prediction of stable crack growth geometry in residually stressed glass

Processing procedures have been developed that produce stress distributions in glass with a maximum compressive stress below the surface. These glasses can exhibit rising apparent fracture toughness behavior and reduced strength variability associated with the stable growth of surface cracks under applied tensile stress. A weight function approach was used to determine stress intensity factors as a function of crack geometry for surface cracks under the effects of stress distributions similar to those found in these glasses. These calculations were then used to predict the growth behavior of surface cracks as a function of the applied and residual stress fields.
Unexpected effects of absorbed normal rabbit serum and bovine serum albumin on survival of Haemophilus influenzae type b in the infant rat.

In the course of using the infant rat model to determine the ability of various rabbit antisera to protect against challenge by Haemophilus influenzae type b we made two unexpected observations. In these experiments 4-day-old rats were inoculated s.c. on the dorsum with either rabbit serum or physiological buffers (sham serum) and then were challenged the next day with H. influenzae type b injected i.p. Bacteremia, as a marker for disease, was measured 24 h later on day 6. We observed the following, (i) Pre-immune, i.e., normal rabbit serum, containing minimal levels of antibodies to outer membrane proteins and depleted of antibodies to capsule and lipopolysaccharide, nevertheless significantly (P < 0.01) protected the rats from challenge with H. influenzae type b when compared to a sham inoculation of buffer; (ii) In the absence of a serum inoculation on day 4 (a buffer was used as a sham serum inoculation), the levels of bacteremia obtained after inoculation with bacteria on day 5 depended upon the composition of the buffer in which the H. influenzae inoculum was suspended. Use of phosphate buffered saline (PBS) resulted in higher levels of bacteremia than PBS containing 0.5% bovine serum albumin (PBS-BSA) (P < 0.001), i.e. the BSA apparently acted to protect the rats from H. influenzae infection. In fact the use of PBS-BSA as an inoculum buffer masked the protective effect noted above of the absorbed normal rabbit serum.
Redox stress and the contributions of BH3-only proteins to infarction.

Ischemia followed by reperfusion is the primary cause of tissue injury and infarction during heart attack and stroke. The initiating stimulus is believed to involve reactive oxygen species that are produced during reperfusion when electron transport resumes in the mitochondria after suppression by ischemia. Programmed death has been shown to be a significant component of infarction, and evidence indicates that multiple pathways are initiated during both ischemia and reperfusion phases. Major infarction is preceded by severe ischemia that includes hypoxia, intracellular acidosis, glucose depletion, loss of ATP, and elevation of cytoplasmic calcium. The superimposition of a reactive oxygen surge on the latter condition provides the impetus for maximal damage. Compelling evidence implicates mitochondria not only as the source of initiating ROS but also as the focal sensors that translate the redox stress signal into a cellular-death response. Pivotal to this response are the BH3-only proteins that are activa...
Aberrant DNA methylation in porcine in vitro-, parthenogenetic-, and somatic cell nuclear transfer-produced blastocysts

Early embryonic development in the pig requires DNA methylation remodeling of the maternal and paternal genomes. Aberrant remodeling, which can be exasperated by in vitro technologies, is detrimental to development and can result in physiological and anatomic abnormalities in the developing fetus and offspring. Here, we developed and validated a microarray based approach to characterize on a global scale the CpG methylation profiles of porcine gametes and blastocyst stage embryos. The relative methylation in the gamete and blastocyst samples showed that 18.5% (921/4,992) of the DNA clones were found to be significantly different (P < 0.01) in at least one of the samples. Furthermore, for the different blastocyst groups, the methylation profile of the in vitro-produced blastocysts was less similar to the in vivo-produced blastocysts as compared to the parthenogenetic- and somatic cell nuclear transfer (SCNT)-produced blastocysts. The microarray results were validated by using bisulfite sequencing for 12 of the genomic regions in liver, sperm, and in vivo-produced blastocysts. These results suggest that a generalized change in global methylation is not responsible for the low developmental potential of blastocysts produced by using in vitro techniques. Instead, the appropriate methylation of a relatively small number of genomic regions in the early embryo may enable early development to occur. Mol. Reprod. Dev. 75: 250–264, 2008. © 2007 Wiley-Liss, Inc.
Real-time NMR investigations of triple-helix folding and collagen folding diseases

Folding of the collagen triple helix provides an opportunity to look at multichain molecular assembly. This triple helix also offers unique advantages for the study of folding because the process is very slow compared to globular proteins, and the kinetics of folding can be obtained in real time by NMR. Studies on triple-helical peptides illustrate the ability to observe kinetic folding intermediates directly and the ability to propose detailed mechanisms of folding through the use of real-time NMR methods. Defective collagen folding has been implicated in various connective tissue diseases and the capacity of NMR to look at the folding of specific sites provides a tool for obtaining information about altered folding mechanisms. Comparison of folding in peptides that model normal and diseased collagens could shed light on the molecular perturbation and the etiology of disease.
Maize Nodal Root Response to Time of Soil Ridging

An improved understanding of maize (Zea mays L.) nodal root response to soil ridging is needed to allow farmers to maximize the benefits of ridge-till tillage systems. Greenhouse (three trials, 1992 to 1994) and field (two sites in Iowa, 1992 and 1993) experiments were conducted with one maize hybrid to examine the effect of time of soil ridging on nodal root development, internode elongation, shoot dry matter, and grain yield. Maize root clumps were evaluated from unridged plants and from plants ridged either at early (V4 to V6) or late (V7) growth stages. Total numbers of nodal roots, numbers of roots per node, numbers of nodes developing functional roots, internode lengths, shoot dry matter, and grain yields (field study) were determined. Time of ridging significantly affected nodal root numbers and internode lengths. In two of the field trials, unridged maize plants produced 42.7 and 48.3 functional nodal roots, whereas plants ridged at growth stage V7 developed significantly more, 47.0 and 56.0 roots, respectively. Internodes 6 and 7, covered with soil during ridging, increased in length by as much as 124% in the field and 175% in the greenhouse when plants were ridged early rather than late. In one field trial, Internode 6 elongated to 44.1 mm with early ridging, but to less than 17.0 mm with either late or no ridging. Shoot dry matter and grain yields generally were not affected by ridging treatments in either field or greenhouse experiments. Later ridging tends to result in shorter internodes and more functional nodal roots which may be important to maize plants in terms of lodging resistance and recovery from corn rootworm (Diabrotica spp.) damage.
Degradation of oxidized proteins by autophagy during oxidative stress in Arabidopsis.

Upon encountering oxidative stress, proteins are oxidized extensively by highly reactive and toxic reactive oxidative species, and these damaged, oxidized proteins need to be degraded rapidly and effectively. There are two major proteolytic systems for bulk degradation in eukaryotes, the proteasome and vacuolar autophagy. In mammalian cells, the 20S proteasome and a specific type of vacuolar autophagy, chaperone-mediated autophagy, are involved in the degradation of oxidized proteins in mild oxidative stress. However, little is known about how cells remove oxidized proteins when under severe oxidative stress. Using two macroautophagy markers, monodansylcadaverine and green fluorescent protein-AtATG8e, we here show that application of hydrogen peroxide or the reactive oxidative species inducer methyl viologen can induce macroautophagy in Arabidopsis (Arabidopsis thaliana) plants. Macroautophagy-defective RNAi-AtATG18a transgenic plants are more sensitive to methyl viologen treatment than wild-type plants and accumulate a higher level of oxidized proteins due to a lower degradation rate. In the presence of a vacuolar H+-ATPase inhibitor, concanamycin A, oxidized proteins were detected in the vacuole of wild-type root cells but not RNAi-AtATG18a root cells. Together, our results indicate that autophagy is involved in degrading oxidized proteins under oxidative stress conditions in Arabidopsis.
Double-layer silicon waveguides in standard silicon for 3D photonics

We demonstrate a 3D photonic technology for fabrication of double-layer silicon waveguides in standard silicon. This technology eliminates the need for silicon-on-insulator (SOI) wafers and can be further expanded to multiple-layer photonics for different applications.
Production of Metallothionein and Heat-Shock Proteins in Response to Metals

Acute stress, such as heat, and some metals, such as arsenite, will induce a specific group of stress proteins referred to as heat-shock proteins. The heat-shock proteins contribute to the survival of cells following a variety of stresses. Similarly, metals such as cadmium and zinc, will increase the levels of metallothionein (MT). The metal-binding protein, MT, has also been found to have a protective role in the cellular response to acute stresses like heavy metals. The purpose of the present study was to examine the production of these proteins in response to metals. Rat hepatocytes were maintained in monolayer culture for 22 hr, and subsequently treated with various concentrations of metals for 4 hr, or incubated at 43.5 degrees C for 15-60 min. Following two washes with fresh media, the cells were labeled with [35S]-methionine (25 microCi/ml) in methionine-free media for 4 hr for determination of heat-shock protein production, or reincubated in fresh media for 20 hr for MT determination. Heat-shock protein production was determined by SDS-polyacrylamide gel electrophoresis followed by autoradiography. The autoradiograms were quantified by densitometric scanning. MT was determined by the Cd/hemoglobin affinity assay. Three metals (arsenite, cadmium, and zinc) strongly increased the heat-shock proteins. Whereas arsenite was a much less effective inducer of MT than was cadmium or zinc, arsenite was as effective as the other metals in inducing heat-shock proteins. Nickel was a good inducer of MT; however, it resulted in only a slight increase in the levels of heat-shock proteins.(ABSTRACT TRUNCATED AT 250 WORDS)
Autoproteolytic Activation of ThnT Results in Structural Reorganization Necessary for Substrate Binding and Catalysis.

cis-Autoproteolysis is a post-translational modification necessary for the function of ThnT, an enzyme involved in the biosynthesis of the β-lactam antibiotic thienamycin. This modification generates an N-terminal threonine nucleophile that is used to hydrolyze the pantetheinyl moiety of its natural substrate. We determined the crystal structure of autoactivated ThnT to 1.8A through X-ray crystallography. Comparison to a mutationally inactivated precursor structure revealed several large conformational rearrangements near the active site. To probe the relevance of these transitions, we designed a pantetheine-like chloromethyl ketone inactivator and co-crystallized it with ThnT. Although this class of inhibitor has been in use for several decades, the mode of inactivation had not been determined for an enzyme that uses an N-terminal nucleophile. The co-crystal structure revealed the chloromethyl ketone bound to the N-terminal nucleophile of ThnT through an ether linkage, and analysis suggests inactivation through a direct displacement mechanism. More importantly, this inactivated complex shows that three regions of ThnT that are critical to the formation of the substrate binding pocket undergo rearrangement upon autoproteolysis. Comparison of ThnT with other autoproteolytic enzymes of disparate evolutionary lineage revealed a high degree of similarity within the proenzyme active site, reflecting shared chemical constraints. However, after autoproteolysis, many enzymes, like ThnT, are observed to rearrange in order to accommodate their specific substrate. We propose that this is a general phenomenon, whereby autoprocessing systems with shared chemistry may possess similar structural features that dissipate upon rearrangement into a mature state.
Ion-cyclotron wave dissipation channel for Alfvén waves

The effect of inhomogeneous velocity flow on Alfven wave dynamics in the solar wind is investigated. Unlike existing studies in this field that model energy deposition from high-frequency waves to solar wind particles, we consider here the possibility of obtaining high-frequency waves (in this case fast magnetosonic waves) from the ordinary Alfven wave spectrum. It is shown that the spatial inhomogeneity of the velocity field can lead to dissipation of Alfven waves through ion-cyclotron resonance. Recent Ultraviolet Coronagraph Spectrometer (UVCS/SOHO) observations indicate that preferential heating and acceleration of heavy ions occurs close to the Sun. The process described here provides a possible interpretation of such solar wind observations.
A hot new way to measure aggression: Hot sauce allocation

Laboratory experiments investigating aggressive behavior have operationalized and assessed aggression in a variety of ways; however, these measures are often problematic because they do not create a situation in which participants perceive potential for real harm to come to the target, there is a risk of actual harm to the target, or they are too familiar to participants. To overcome these limitations, we developed a new method for measuring aggression, specifically, the amount of hot sauce administered to a target known to dislike spicy foods. We summarize a series of experiments assessing theory-based hypotheses regarding aggression in which this measure is employed. We then briefly consider the strengths and limitations of this new measure. Aggr. Behav. 25:331–348, 1999. © 1999 Wiley-Liss, Inc.
Differences in prepuberal neonatally estrogenized or androgenized male rats.

Summary: The main objective of this work was to analyze the different effects produced in prepuberal male rats by neonatal androgenization or estrogenization. For this purpose male Wistar rats were injected on day one of life with 500 μg of estradiol benzoate (estrogenized animals), 500 μg of testosterone propionate (androgenized animals) or olive oil (control animals) and decapitated on day 15. At the moment of decapitation estrogenized animals showed decreases in body, testes, prostate and adrenal weights, increases in pituitary, seminal vesicles and epididymis weights, an increase in prolactin plasma levels and a decrease in those of androgens. Androgenized animals showed only decreased testes and epididymis weights and androgen plasma levels. These results evidence the presence of important qualitative differences in prepuberal neonatally estrogenized or androgenized rats, especially in the accessory sex organs. Unterschiede bei prapuberalen mannlichen Ratten, die neonatal oestrogenisiert bzw. androgenisiert wurden Zusammenfassung: Diese Arbeit will die unterschiedlichen Einflusse analysieren, die bei prapuberalen Ratten festzustellen waren, welche neonatal oestrogenisiert bzw. androgenisiert waren. Hierzu erhielten mannliche Wistar-Ratten am ersten Lebenstag 500 μg Oestradiolbenzoat, 500 μg Testosteronpropionat bzw. Olivenol. Am 15. Tag wurden die Tiere dekapitiert; zu diesem Zeitpunkt zeigten die oestrogenisierten Tiere ein reduziertes Gewicht sowie auch von Prostata, Hoden und Nebennieren, dagegen einen Anstieg des Ge-wichts der Hypophyse, der Samenblasen und des Nebenhodens sowie einen Anstieg der Prolaktinplasmawerte, jedoch einen Abfall der Androgene. Die androgenisierten Tiere zeigten demgegenuber lediglich einen Abfall des Gewichts von Hoden und Nebenhoden sowie der Androgenplasmawerte. Daraus wird abgeleitet, das diese Resultate ein Beweis. fur die Anwesenheit wichtiger, qualitativer Unterschiede bei prapuberalen mannlichen Ratten sind, wenn diese neonatal oestrogenisiert bzw. androgenisiert wurden, vor allem hinsichtlich der Sexualorgane.
Nonclassical protein sorting.

Recent characterization of the major protein-targeting systems in both yeast and mammalian cells has provided detailed descriptions of how cellular transport processes operate. Increasingly, however, novel protein-sorting mechanisms are being uncovered. These newly discovered ‘alternative' mechanisms of protein sorting ensure accurate delivery of numerous cellular constituents either to their resident compartment or, in many cases, to the cellular protein-degradation machinery. Like the better characterized ‘classical' protein-sorting systems, ‘nonclassical' targeting mechanisms involve both membrane translocation through protein channels and vesicle-mediated transport. This review discusses our current understanding of these nonclassical protein-sorting pathways and their role in eukaryotic cells.
Separation of church and space: Religious influences on public support for U.S. space exploration policy

Abstract Despite growing interest in the relationship between religion and outer space, the influence of religion on space policy attitudes remains a mostly unexplored topic. This study fills this research gap by treating space exploration as a policy issue for examination by religion and politics theory. It uses data from the General Social Survey and three Pew surveys to construct several logistic regression models. Space policy support, the dependent variable, is operationalized in seven ways as the antecedents of policy views (i.e., space knowledge and interest), actual policy/funding views, and policy expectations. Religion, the key independent variable, is operationalized as belonging (tradition), behavior (church attendance), beliefs, and salience. In addition, one survey permits the identification of the nature of science messages espoused by clergy. The findings reveal that Evangelical Protestants in the U.S. are the least supportive of space policy. However, evidence shows that pro-science messages from the pulpit can change Evangelicals' perceptions of space exploration. The article concludes with calls for increased, concerted outreach to Evangelicals and other religious publics by the space community. These efforts are essential if the American republic will pursue greater space exploration in the near future. Ultimately, religions must ensure their survival by embracing space.
Hip Dysplasia Is More Severe in Charcot-Marie-Tooth Disease Than in Developmental Dysplasia of the Hip

Background Patients with Charcot-Marie-Tooth disease may develop hip dysplasia. Hip geometry in these patients has not been well described in the literature.
Effects of glycose on NADP and NAD glutamate dehydrogenase activities and their relation to ammonium and pH levels in cultures of Bipolaris maydis race T

NADP-glutamate dehydrogenase (NADP-GDH) and NAD-glutamate dehydrogenase (NAD-GDH) activities from Bipolaris maydis race T (ATCC 36180) were determined by measuring the change in absorbance at 340 nm of either reduced NADP or NAD in a reaction mixture of NH4C1, α-ketoglutarate and a cell free extract of the fungus. NADP-GDH activity was high at 48 h, but low at 72 and 96 h when the fungus was incubated on a reciprocal shaker at 28 °C in a mineral salts medium containing 2 g/l glucose and 4 g/l Lasparagine. In contrast, in these cultures NAD-GDH activity was low at 48 h, but high at 72 and 96 h. At 72 and 96 h glucose was not detected in the culture medium. In addition, levels of ammonium and pH increased from 0.0 μmoles/ml and pH 5.8 at 48 h to 10.6 μmoles/ml and pH 7.2 at 72 h, and to 23.0 μmoles/ml and pH 8.4 at 96 h. Fungal mycelia were transferred after 48 h of incubation on media containing 2 g/l glucose and 4 g/l L-asparagine to fresh media containing 0, 2 or 5 g/l glucose with and without 4 g/l L-asparagine. Twenty-four h after transfer to fresh media containing 5 g/l glucose with L-asparagine or 2 or 5 g/l glucose without L-asparagine, NADP-GDH activity was high and NAD-GDH activity was low. Glucose was detected in the culture medium, ammonium was not detected and the pH remained unchanged or decreased. In contrast, 24 h after transfer to fresh media with 0 or 2 g/l glucose with L-asparagine and on media lacking glucose or L-asparagine, NADP-GDH activity was low and NAD-GDH activity was high. Glucose was not detected in the culture medium, ammonium levels were high and the pH increased. Thus, accumulation of ammonium and pH increases accompanying depletion of glucose in a L-asparagine medium could be related to a change in the capacity of B. maydis race T to assimilate and produce ammonium via pathways involving glutamate dehydrogenases.
Information Matrix for Pareto(IV), Burr, and Related Distributions

Abstract In this paper the exact form of information matrix for Pareto(IV) and related distributions is determined. The Pareto(IV) family being very general includes more specialized families of Pareto(I), Pareto(II), and Pareto(III), and the Burr family of distributions, as special cases. These distributions, for example, arise as tractable parametric models in actuarial science, economics, finance, and telecommunications. Additionally, a useful mathematical result with its own domain of importance is obtained. In particular, explicit formula for the improper integral , with b > 0 and non-negative integer m, is derived.
A laboratory scale piezoelectric array for underwater measurements of the fluctuating wall pressure beneath turbulent boundary layers

To capture the full spectrum of the fluctuating wall pressure beneath a turbulent boundary layer (TBL) provides a unique challenge in transducer design. This paper discusses the design, construction and testing of an array of surface-mounted piezoelectric ceramic elements with the goal of having both the spatial resolution and the frequency bandwidth to accurately sense the low-frequency, low-wavenumber events beneath a TBL at moderately low Reynolds numbers. The array is constructed from twenty 1.27 cm tall prismatic rods with 0.18 cm × 0.16 cm cross-section made of Navy type II piezoelectric ceramic material. Calibration was performed by comparing the response of a Navy H56 precision-calibrated hydrophone to the outputs of each element on the array for a given input from a Navy J9 projector. The elements show an average sensitivity of −184 dB (re: 1 V μPa −1 ) and are assembled with a centre-to-centre spacing of 0.2 cm. Measurements of the fluctuating wall pressure below a 2d TBL with Reynolds numbers (based on momentum thickness) ranging from 2100 to 4300 show that the dimensions of the elements are between 64 and 107 viscous length units, respectively. A spatial and temporal footprint of the fluctuating wall pressure reveals convective speeds averaging 75% of the free stream velocity.
Memory of simple learning in young, middle-aged, and aged C57/BL6 mice.

Age differences in retention were studied by comparing habituation of activity in 2-, 12- and 24-month-old mice as a function of repeated exposures to a novel environment. Mice were placed in a small chamber for 3 min and retested both 4 and 8 days later. Between-session forgetting was evident in 12- and 24-month-old mice because (1) total activity scores on retest days were higher than those for 2-month-old mice and (2) activity levels at the end of one session and the beginning of the next session did not differ in older mice, whereas activity was lower at the beginning of a session in 2-month-old mice. Retention deficits were observed in all age groups when the interval between the first and second exposures was increased to 8 days.
Meconium aspiration syndrome in term neonates with normal acid-base status at delivery: Is it different?

Abstract Objective: Our aim was to compare the clinical characteristics of meconium aspiration syndrome in cases with pH ≥7.20 and in those with pH Study Design: Medical records of diagnostic codes from the International Classification of Diseases, Ninth Revision, were used to identify neonates with severe meconium aspiration syndrome who had been delivered at our institution from 1994 through 1998. Severe meconium aspiration syndrome was defined as a mechanical ventilator requirement of >48 hours. Clinical data including neonatal outcomes of cases of meconium aspiration syndrome associated with umbilical pH ≥7.20 at delivery were compared with data on outcomes of cases with pH Results: During this 4-year study period, 4985 singleton term neonates were delivered through meconium-stained amniotic fluid. Forty-eight cases met all study criteria, and pH values at delivery were as follows: pH ≥7.20, n=29, and pH P = 1.0). Conclusion: Normal acid-base status at delivery is present in many cases of severe meconium aspiration syndrome, which suggests that either a preexisting injury or a nonhypoxic mechanism is often involved. (Am J Obstet Gynecol 2001;184:1422-6.)
Free and esterified sterols of cotton buds and anthers

Capillary gas liquid chromatography analyses were conducted on free and esterified sterol fractions of cotton (Gossypium hirsutum cv. Stoneville 213) floral buds and anthers. The free sterols of both cotton buds and anthers consist mainly of the common plant sterols sitosterol, stigmasterol and 24ζ-methylcholest-5-en-3β-ol. The composition of esterified sterols of cotton buds and anthers were similar, and consisted of pollinastanol, 31-norcycloartanol, cycloartenol, 31-norcycloartenol, 24-dehydropolinastanol and sitosterol. Desmosterol was also present in both the free and esterified sterols of anthers. The identities of the sterols were confirmed by gas chromatography-mass spectrometry analyses. Esterified sterols accounted for 46.7 and 88.7% of total sterols of cotton bud and anthers, respectively. The ratio of esterified sterol to free sterol per gram of tissue is about 8∶1 in anthers. The Δ5-sterols of the esterified sterols of cotton buds and anthers account for only 17 and 9.2% of the total sterols, respectively.
Root system morphology of Quercus rubra L. planting stock and 3-year field performance in Iowa

On 3 sites, 3-year performance of 1+0 northern red oak (Quercus rubra L.) seedlings was evaluated with respect to initial root system grade. Seven hundred twenty nursery-run bareroot northern red oak seedlings were graded according to numbers of large (>1mm) first-order lateral roots and outplanted in spring 1987 on eight 90-tree plots distributed among three sites in central Iowa. Survival, height growth, and diameter growth were significantly greater for seedlings with 10 or more large first-order lateral roots than for seedlings with 4 or fewer. Seedling survival and growth were significantly and positively related to initial root grade. First-year height growth, however, was significantly and negatively correlated with initial height. Combined results for seedling survival and growth indicated that red oak seedlings with five or more large first-order lateral roots have a greater probability of success both in terms of survival and early growth than do those with four or fewer first-order lateral roots.
An electron microscopic evaluation of bacteria inhabiting rotating biological contactor biofilms during various loading conditions

Abstract The biofilms growing in all compartments of two rotating biological contactors, subjected to various organic loading rates during treatment of municipal wastewater, were examined by transmission electron microscopy. The morphological and ultrastructural characteristics of the biofilms correlated closely with the compartmental organic loading rate to which they were exposed. At high organic loading rates, oxygen limitations were indicated by the presence of large numbers of cells with poly‐β‐hydroxybutyrate (PHB) and sulphur‐like inclusions. As the loading rate decreased there was a decrease in PHB and sulphur‐like storage in the biofilm bacteria. At low loading rates, pros‐thecate bacteria were the predominant biofilm constituents. In compartments where nitrification occurred, bacteria that possessed extensive cytomembranes and convoluted cell surfaces predominated.
Estimating Latent Variable Interactions with the Unconstrained Approach: A Comparison of Methods to Form Product Indicators for Large, Unequal Numbers of Items

This Monte Carlo simulation study investigated methods of forming product indicators for the unconstrained approach for latent variable interaction estimation when the exogenous factors are measured by large and unequal numbers of indicators. Product indicators were created based on multiplying parcels of the larger scale by indicators of the smaller scale, multiplying the three most reliable indicators of each scale matched by reliability, and matching items by reliability to create as many product indicators as the number of indicators of the smallest scale. The unconstrained approach was compared with the latent moderated structural equations (LMS) approach. All methods considered provided unbiased parameter estimates. Unbiased standard errors were obtained in all conditions with the LMS approach and when the sample size was large with the unconstrained approach. Power levels to test the latent interaction and Type I error rates were similar for all methods but slightly better for the LMS approach.
Some Acute and Chronic Effects of Dieldrin on the Sailfin Molly, Poecilia Latipinna

Abstract A flowing water dilutor system is described that delivers known, consistent concentrations of pesticide in filtered sea water to six pairs of 90 liter aquaria. In this system sailfin mollies, Poecilia latipinna, were exposed to various concentrations of dieldrin in both acute and chronic experiments. More than half of the experimental fishes survived 0.0015 and 0.00075 ppm of pesticide for 34 weeks. However, 0.012 ppm dieldrin killed all exposed fishes within the first week. Fishes exposed to 0.0075 ppm of pesticide contained more than 1.0 ppm in gills and blood after only one hour. After 144 hours exposure gills, blood, and brain each contained more than 6.0 ppm as determined by gas chromatography. Dieldrin concentrations in the gut, liver, and muscle after 144 hours ranged from 2.0 ppm to over 8 ppm. The mortality rate was accelerated after twenty-four hours when all sampled tissues contained between 5 and 11 ppm of dieldrin.
Patients' autonomy: three models of the professional-lay relationship in medicine.

Health care is not merely a matter of individual encounters between patients and physicians or other health care personnel. For patients and those who provide health care come to these encounters already possessed of learned habits of perception and judgment, valuation and action, which define their roles in relation to one another and affect every aspect of their encounter. So the presuppositions of these encounters must be examined if our understanding of patients' autonomy is to be complete. In this paper I sketch three models of what is presupposed in the relationship between the health care professional and the lay patient; and I discuss the ways in which patients' autonomy is preserved and/or compromised under each of the three models. The models discussed are the Guild Model, the Commercial Model, and the Interactive Model.
A quantitative measure of the reliability of searches of spectral libraries

Abstract A quantitative measure of library search reliability has been developed. Applications of the quantitative reliability metric (QRM) for evaluating the reliability of library searches for unknown target spectra and the use of this measure to detect the failure of a library search caused by noise, contaminant peaks and missing library spectra are discussed. The effects of noise and composite infrared spectra of mixtures on the QRM are examined for test sets of 561 infrared spectra. The QRM is also used to evaluate the performance of a search of an infrared library compressed by eigenvector projection.
Numerical modeling of cyclic mobility based on fuzzy-set concepts in plasticity theory

Abstract In this paper, the application of an efficient, transparent and accurate kinematic-cyclic constitutive model based on the fuzzy-set concepts and incremental plasticity theory is presented to show its capability in modeling cyclic mobility of saturated granular soil. The nature and kinematic mechanism of the membership functions in the fuzzy-set constitutive model are illustrated. The model’s capability of modeling soil dilatancy is investigated. Important features of volume change and pore water pressure build-up related to soil cyclic mobility are captured. The formulation of the proposed model is relatively simple and it can be readily implemented in finite element codes. The enhanced fuzzy-set model is capable of simulating ground motion problems particularly related to cyclic mobility, soil liquefaction, and spreading behavior.
Microscopic versus empirical effective interactions in a single j shell

Effective-interaction matrix elements within a single j shell can be determined directly from experimental data. Such matrix elements have been found to be much different from those calculated microscopically within a complete major shell. The recent work of Moszkowski et al. showed that this difference is at least partially due to the severe truncation to a single j shell. We have constructed the microscopic effective interaction for a single j shell using two different methods: (1) simple perturbation theory and (2) explicit projection from the full major shell to a single j shell. We conclude that the empirical matrix elements and the full major-shell matrix elements should not agree, since the model spaces are different. On top of this the empirical values and the microscopic results for a single j shell would be expected to be similar only when the configurations vertical-bar ( j/sup 2/) JT> are very pure.
Families of transposable elements, population structure and the origin of species

Background Eukaryotic genomes harbor diverse families of repetitive DNA derived from transposable elements (TEs) that are able to replicate and insert into genomic DNA. The biological role of TEs remains unclear, although they have profound mutagenic impact on eukaryotic genomes and the origin of repetitive families often correlates with speciation events. We present a new hypothesis to explain the observed correlations based on classical concepts of population genetics.
Interrelationships of desoxycorticosterone, cortisone and vitamin C in the genesis of mesenchymal lesions.

SummaryCortisone inhibits many of the manifestations of scurvy in the guinea pig while desoxycorticosterone aggravates the condition. These activities of the hormones probably depend on their actio...
Thermal blooming of rapidly slued laser beams

Thermal blooming of laser beams propagating through the atmosphere has generally been treated for cases of small wind speed transverse to the beam. The present calculation examines the associated density changes for air moving through a beam at near sonic speeds. The problem is treated for the one-dimensional case only; an exact solution to the nonlinear hydrodynamic equations for the steady state is derived. The solution shows that, at near sonic speeds, the density changes grow drastically with Mach value, while agreeing with the previous results at low wind speeds. In the vicinity of Mach I, the solution becomes invalid, probably due to the nonexistence of a steady state. The effect of the density changes on the beam are not calculated here.
A Facile Enzymatic Synthesis of Uridine Diphospho-[14C]galacturonic Acid

Galacturonic acid (GalA) is a major component of plant cell-wall-derived pectins. It can be also found in the cell-surface polysaccharides of different microorganisms, including several symbiotic and pathogenic bacteria. Uridine diphosphogalacturonic acid (UDP-GalA) is a likely donor for GalA during the biosynthesis of these polysaccharides. A highly efficient, yet simple, method is presented for generating and purifying UDP-[14C]GalA. Commercially available UDP-[14C]-galactose was quantitatively oxidized (>95% conversion) to UDP-[14C]GalA in the presence of high levels of galactose oxidase and catalase, at prolonged incubation times. Following this one-step enzymatic oxidation, UDP-[14C]GalA was purified using a polyethyleneimine cellulose column with a single-step 1 M NaCl elution. The authenticity of the purified UDP-[14C]GalA was verified by its relative mobility on thin-layer chromatograms, analysis of its chemical hydrolysis products, and 1H NMR spectroscopy. Our yield of >90% is much higher than by previously described methods. The method may serve as a prototype for the preparation of other radiolabeled uronic acids and their nucleotide derivatives.
Millimeter-wave interferometric imaging sensors

Interferometric imaging holds the potential for significant improvements in capability for compact, close range millimeter-wave imaging sensors. This paper reviews the fundamental principles of interferometric imaging. Standard imaging array designs and their effect on resulting images are discussed, and simulated reconstructions of notional scenes are presented.
Developing an Efficient Region Growing Engine for Image Segmentation

Image segmentation is a crucial part of image processing applications. Currently available approaches require significant computer power to handle large images. We present an efficient region growing algorithm for the segmentation of multi-spectral images in which the complexity of the most time-consuming operation in region growing, merging segment neighborhoods, is significantly reduced. In addition, considerable improvement is achieved by preprocessing, where adjacent pixels with close colors are gathered and used as initial segments. The preprocessing provides substantial memory savings and performance gain without a noticeable influence on segmentation results. In practice, there is an almost linear dependency between the runtime and image size. Experiments show that large satellite images can be processed using the new algorithm in a few minutes on a moderate desktop computer.
Structure of variant-3 scorpion neurotoxin from Centruroides sculpturatus Ewing, refined at 1.8 A resolution.

The three-dimensional structure of the variant-3 protein neurotoxin from the scorpion Centruroides sculpturatus Ewing has been determined by X-ray diffraction data. The initial model for the 65-residue protein was obtained at 3 A resolution by multiple-isomorphous-replacement methods. The structure was refined at 1·8 A resolution by restrained difference-Fourier methods, and by free-atom, block-diagonal least-squares. Considering the 4900 reflections for which d = 1·8−7 A and F0 > 2·5σ(F0), the final R-index is 0·16 for the restrained model, and 0·14 for the free-atom model. Average estimated errors in atomic co-ordinates are about 0·1 A. The refined structure includes 492 protein atoms; one molecule of 2-methyl-2,4-pentanediol, which is tightly bound in a hydrophobic pocket on the surface of the protein; and 72 additional solvent sites. The major secondary structural features are two and a half turns of α-helix and a three-strand stretch of antiparallel β-sheet. The helix is connected to the middle strand of the β-sheet by two disulfide bridges, and a third disulfide bridge is located nearby. Several loops extend out of this dense core of secondary structure. The protein displays several reverse turns and a highly controted proline-rich, COOH-terminal segment. One of the proline residues (Pro59) assumes a cis-conformation. The structure involves 44 intramolecular hydrogen bonds. The crystallographic results suggest two major corrections in the published primary structure; one of these has been confirmed by new chemical sequence data. The protein displays a large flattened surface that contains a high concentration of hydrophobic residues, along with most of the conserved amino acids that are found in the scorpion neurotoxins.
Extraneous particles shed from large soil particles

Abstract Large soil particles (predominantly montmorillonite) shed small (submicron- and micron-sized) particles when collected in water or on membrane filters or upon collision with an obstacle. Small particles present in large numbers in the interstices of a large soil particle are released into air or water and form an independent aerosol or hydrosol colloidal suspension leaving the parent particles practically unchanged. The shed particles did not originally belong to the aerosol or hydrosol population but are released in the sampling apparatus; consequently the determined concentration of aerosol particles is not representative of the aerosol concentration in air. Da- and h-μm aerosol particles act as accretion centers for cloud droplets when ingested by a cloud; they form large drops which shatter and form numerous fragments. The shed hydrosol particles in water drops formed on those fragments provide additional freezing nuclei that freeze these water drops. Studies of natural aerosol particles must include not only their size, surface structure and chemical composition, but also the function those aerosol particles perform in nature as condensation and ice-forming nuclei.
Influence of hydroxypropyl-β-cyclodextrin (HPCD) on the bioavailability and biodegradation of pyrene

It is well known that the limited aqueous solubilities of polycyclic aromatic hydrocarbons (PAH) often reduce their bioavailability to bacterial populations. The objective of this study was to test the impact of a solubility-enhancement reagent, hydroxypropyl-beta-cyclodextrin (HPCD), on the bioavailability and biodegradation of pyrene. No measurable loss of pyrene occurred for the control vials throughout the first 22 weeks of the experiment, indicating the absence of mass loss via abiotic transformation and volatilization. The vials containing pyrene and the degrader isolate (Burkholderia CRE 7), but no HPCD, also exhibited no measurable loss of pyrene throughout the experiment. Conversely, biodegradation of pyrene appears to have been initiated after approximately 15 weeks for the vials containing 10(4) mg l(-1) HPCD. By the end of the experiment, approximately 14% (w/w) of the pyrene was biodegraded in the presence of HPCD. These results indicate that HPCD may be useful for enhancing the bioavailability and biodegradation of pyrene and other PAHs.
Exact expected values of variance estimators for simulation

We formulate exact expressions for the expected values of selected estimators of the variance parameter (that is, the sum of covariances at all lags) of a steady-state simulation output process. Given in terms of the autocovariance function of the process, these expressions are derived for variance estimators based on the simulation analysis methods of nonoverlapping batch means, overlapping batch means, and standardized time series. Comparing estimator performance in a first-order autoregressive process and the M/M/1 queue-waiting-time process, we find that certain standardized time series estimators outperform their competitors as the sample size becomes large. © 2007 Wiley Periodicals, Inc. Naval Research Logistics 54: 397-410, 2007
An unexpected role for normal accommodative vergence in strabismus and amblyopia.

Accommodative vergence was measured using the Muller experimental paradigm in which target movement along the line of sight of the viewing eye results in large movement of the fellow (covered) eye. Our paper demonstrates an unexpected predominance of accommodative vergence over disparity vergence in patients with constant strabismus amblyopia, intermittent strabismus, and amblyopia without strabismus. Comparison of accommodative vergence responses in these patients with responses from normal subjects using symmetrical and asymmetrical targets under binocular and monocular conditions established the normal character of the patients' accommodative vergence and the absence of disparity vergence in most of them. The intermittent absence of disparity vergence in certain of our patients--some with surgically corrected strabismus, some with moderate amblyopia, and some with amblyopia treated with orthoptics--raises questions of clinical and neurophysiological interest. Preliminary results on the effects of amblyopia on accommodative responses are also presented.
Generation of Submicron Mass/Volume-Monodisperse Aerosols with a Nebulizer-Impactor-Electrostatic Classifier System

A study was undertaken to investigate the mass size dispersion of particles classified according to their electrical mobilities. This is of primary concern in experiments that measure a concentration dependent property of the classified particles. Initially, the mass size distribution of particles produced by the 3-jet Collison, 6-jet Collison, and Misty-Ox nebulizers was measured. A 0–2 stage impactor was placed after the nebulizers and the size mass distribution was measured again. The polydisperse particle stream was then used to generate “size classified” aerosol and the mass size distribution of the equal mobility particles was calculated and measured. It was found that without an impactor in line, the aerosol stream contained a significant mass fraction of multiply charged particles. When an impactor was inserted directly after the nebulizers, the multiply charged particles were effectively removed and the particles were nearly monodisperse.
On-Board Imaging Validation of Optically Guided Stereotactic Radiosurgery Positioning System for Conventionally Fractionated Radiotherapy for Paranasal Sinus and Skull Base Cancer

Purpose To evaluate the positioning accuracy of an optical positioning system for stereotactic radiosurgery in a pilot experience of optically guided, conventionally fractionated, radiotherapy for paranasal sinus and skull base tumors. Methods and Materials Before each daily radiotherapy session, the positioning of 28 patients was set up using an optical positioning system. After this initial setup, the patients underwent standard on-board imaging that included daily orthogonal kilovoltage images and weekly cone beam computed tomography scans. Daily translational shifts were made after comparing the on-board images with the treatment planning computed tomography scans. These daily translational shifts represented the daily positional error in the optical tracking system and were recorded during the treatment course. For 13 patients treated with smaller fields, a three-degree of freedom (3DOF) head positioner was used for more accurate setup. Results The mean positional error for the optically guided system in patients with and without the 3DOF head positioner was 1.4 ± 1.1 mm and 3.9 ± 1.6 mm, respectively ( p p = .057). No positional drift was observed in the patients without the 3DOF head positioner. Conclusion Our initial clinical experience with optically guided head-and-neck fractionated radiotherapy was promising and demonstrated clinical feasibility. The optically guided setup was especially useful when used in conjunction with the 3DOF head positioner and when it was recalibrated to the shifts using the weekly portal images.