cssi/SciSciGPT-SciSciNet huggingface dataset:
A postimplantation lethal mutation induced by transgene insertion on mouse chromosome 8.

We have produced three lines of transgenic mice that contain additional copies of the mouse phosphoglycerate kinase 1 (Pgk1) gene. Two of these lines, 94-A and 94-K, which are descendants of a common founder, did not produce liveborn progeny carrying two copies of these transgenes (i.e., A/A, K/K, or A/K). Genotyping of midgestation embryos showed that A/K embryos are dead by Embryonic Day 10. Comparison of the level of transgene expression in the three transgenic lines ruled out PGK1 toxicity as the cause of death of A/A, A/K, and K/K embryos. The death of A/A, K/K, and A/K transgenic mice was therefore attributed to an insertional mutation disrupting a gene or genes essential for normal embryogenesis. Analysis of the structure of the 94-A and 94-K transgenes indicated that they differ in the number of tandem repeats and in the positions of the transgene-cellular DNA junctions. To determine if the two transgenes represent a single integration followed by a rearrangement or two independent integration events, we cloned the endogenous sequences surrounding the 94-A and 94-K transgene insertion sites. Restriction analysis of the isolated genomic clones indicated that the endogenous sequences abutting the 3{prime} ends of the 94-A and 94-K transgenes are more » separated by less than 20 kb, providing strong support for the single integration model. Further analysis indicated that the 94-A transgene is associated with a deletion of at least 18 kb and is located in the vicinity of a widely transcribed endogenous gene. Chromosomal mapping of the endogenous sequences flanking the 94-A and 94-K transgene insertions using mouse -hamster somatic cell hybrids and a (C57BL/6J X SPRET/Ei)F1 X SPRET/Ei backcross panel allowed us to assign the 94-A(K) transgene insertion to the subcentral region of mouse chromosome 8. 100 refs., 10 figs., 5 tabs. « less
The effects of books and gender constancy development on kindergarten children's sex-role attitudes☆

Abstract The effects of symbolic models and level of gender understanding on children's sex-role attitudes was investigated. Kindergarten boys and girls heard and discussed books whose characters depicted either traditional or nontraditional sex-role behaviors. Attitudes toward males and females were measured before and after the picture book treatment. When the study began, children were screened for gender understanding so that half were able to make other-gender constancy judgments, and half were not able to make other-gender constancy judgments. Prior to the treatment, boys and children who had attained gender constancy were slightly negative toward males and neutral toward females, whereas girls and children who had not attained gender constancy were very negative toward males and very positive toward females. Exposure to traditional books had the effect of enhancing attitudes toward males and decreasing attitudes toward females. Exposure to nontraditional books had the opposite effect of decreasing attitudes toward males and enhancing attitudes toward females. The effects of the picture book treatment on attitudes toward females were more pronounced for children who had attained other-gender constancy. Implications for social learning and cognitive-developmental theories of sex-role development are discussed.
Lake-sediment evidence for the date of deglaciation of the Hidden Lake area, Kenai Peninsula, Alaska

An abrupt environmental change is reflected in a core from Hidden Lake, Alaska, by differences in sediment type, chlorite crystallinity, and content of organic carbon and water of the sediments. This abrupt change in the sedimentary record occurred about 14,500 14C yr ago and probably marks the time of recession of the glacier from the Hidden Lake drainage basin. Deglaciation of the area was then underway, and rock flour was being deposited in the lake. After recession of the glacier from the Hidden Lake drainage basin, rock flour was no longer introduced, and organic-matter content of the sediment increased. By the dating of these changes in sediment type, we show that retreat of glaciers in this area took place significantly earlier than previously estimated; this agrees with the timing of retreat of alpine glaciers elsewhere in western North America.
Prior colonization is associated with increased risk of antibiotic-resistant Gram-negative bacteremia in cancer patients

We hypothesized that prior colonization with antibiotic-resistant Gram-negative bacteria is associated with increased risk of subsequent antibiotic-resistant Gram-negative bacteremia among cancer patients. We performed a matched case-control study. Cases were cancer patients with a blood culture positive for antibiotic-resistant Gram-negative bacteria. Controls were cancer patients with a blood culture not positive for antibiotic-resistant Gram-negative bacteria. Prior colonization was defined as any antibiotic-resistant Gram-negative bacteria in surveillance or non-sterile-site cultures obtained 2–365 days before the bacteremia. Thirty-two (37%) of 86 cases and 27 (8%) of 323 matched controls were previously colonized by any antibiotic-resistant Gram-negative bacteria. Prior colonization was strongly associated with antibiotic-resistant Gram-negative bacteremia (odds ratio [OR] 7.2, 95% confidence interval [CI] 3.5–14.7) after controlling for recent treatment with piperacillin-tazobactam (OR 2.5, 95% CI 1.3–4.8). In these patients with suspected bacteremia, prior cultures may predict increased risk of antibiotic-resistant Gram-negative bacteremia.
An Epidemiological Network Model for Disease Outbreak Detection

Background Advanced disease-surveillance systems have been deployed worldwide to provide early detection of infectious disease outbreaks and bioterrorist attacks. New methods that improve the overall detection capabilities of these systems can have a broad practical impact. Furthermore, most current generation surveillance systems are vulnerable to dramatic and unpredictable shifts in the health-care data that they monitor. These shifts can occur during major public events, such as the Olympics, as a result of population surges and public closures. Shifts can also occur during epidemics and pandemics as a result of quarantines, the worried-well flooding emergency departments or, conversely, the public staying away from hospitals for fear of nosocomial infection. Most surveillance systems are not robust to such shifts in health-care utilization, either because they do not adjust baselines and alert-thresholds to new utilization levels, or because the utilization shifts themselves may trigger an alarm. As a result, public-health crises and major public events threaten to undermine health-surveillance systems at the very times they are needed most. Methods and Findings To address this challenge, we introduce a class of epidemiological network models that monitor the relationships among different health-care data streams instead of monitoring the data streams themselves. By extracting the extra information present in the relationships between the data streams, these models have the potential to improve the detection capabilities of a system. Furthermore, the models' relational nature has the potential to increase a system's robustness to unpredictable baseline shifts. We implemented these models and evaluated their effectiveness using historical emergency department data from five hospitals in a single metropolitan area, recorded over a period of 4.5 y by the Automated Epidemiological Geotemporal Integrated Surveillance real-time public health–surveillance system, developed by the Children's Hospital Informatics Program at the Harvard-MIT Division of Health Sciences and Technology on behalf of the Massachusetts Department of Public Health. We performed experiments with semi-synthetic outbreaks of different magnitudes and simulated baseline shifts of different types and magnitudes. The results show that the network models provide better detection of localized outbreaks, and greater robustness to unpredictable shifts than a reference time-series modeling approach. Conclusions The integrated network models of epidemiological data streams and their interrelationships have the potential to improve current surveillance efforts, providing better localized outbreak detection under normal circumstances, as well as more robust performance in the face of shifts in health-care utilization during epidemics and major public events.
Sex roles and the psychiatric referral process

Three studies were undertaken to explore the relationship between sex-role standards and the psychiatric referral process. Based on observations from previous literature it was hypothesized that children who exhibited behavioral characteristics inappropriate to their sex would be more likely to be referred to psychiatric facilities than would children who exhibited behavioral characteristics appropriate to their sex. The first study examined the records of an outpatient child-guidance clinic. In accord with the hypothesis, it was found that more boys than girls were referred for being emotional or passive and more girls than boys were referred for being defiant and verbally aggressive. In the two subsequent studies, samples of parents and graduate students in clinical and school psychology read hypothetical case studies in which identical behavior problems were attributed either to a boy (Bob) or to a girl (Barbara). The data from the two samples indicated that the child exhibiting the behavior inappropriate to his/her sex was seen as more severely disturbed, as more in need of treatment, and as having a less successful future than the child exhibiting sex-role appropriate behaviors.
Calculator least squares evaluation of k, yo, and y∞ for the first order rate equation

Abstract A calculator program 1 KIN 3 is described for computing by least squares the three parameters of the first order rate equation. This may be considered as abstracted from the program LSK1N 1. Coding is for the Hewlett-Packard HP-67 and HP-97 programmable calculators, but the algorithms and the coding are described in detail so as to be readily adaptable to other calculators. The y values are assigned unit weight; in practice this scalar weighting does not appreciably bias the k values.
Paper: Bifurcation to divergence and flutter in flow-induced oscillations: an infinite dimensional analysis

We outline the application of center manifold theory to a problem of flow-induced vibrations in which bifurcations occur under the action of control parameters. Using these techniques, the governing nonlinear partial differential equation (PDE) can be replaced locally by a vector field on a low dimensional manifold. The bifurcations thus detected, including 'global' bifurcations, yield a useful description of the qualitative dynamics of the original PDE.
Aedes aegypti transferrin. Gene structure, expression pattern, and regulation

Mosquitoes and all other insects so far examined have an abundant haemolymph transferrin (Tsf). The exact function of these proteins has not been determined, but they may be involved in iron transport, in oogenesis and in innate immune defence against parasites and pathogens. The Tsf gene of Aedes aegypti has been cloned and sequenced. It contains a single small intron, which contrasts it to vertebrate Tsf genes that contain up to sixteen introns. The promoter region of the gene is rich in putative NF-kappaB binding sites, which is consistent with the postulated role of Tsf in insect innate immunity. Tsf message levels are very low in embryos and early larvae, but high in late larvae, pupae and adults. Western blotting experiments revealed high levels of Tsf protein in pupae and adults. Late larvae and ovaries of blood-fed mosquitoes have little intact protein, but two prominent proteolytic degradation products. These may represent biologically active peptides, as has been shown for other organisms. Tsf message is down-regulated by inorganic iron in the diet or environment, but up-regulated by a blood meal in the adult female. The up-regulation following a blood meal may, in part, be due to the decrease in juvenile hormone (JH) that is known to follow blood feeding. Treatment of blood-fed females with methoprene, an analogue of JH, resulted in decrease of the Tsf message.
Effects of low fluences of radiations found in space on cellular systems.

Purpose: In recent years, there has been a large increase in the amount of space-related radiation biology research being conducted. This review will discuss selected issues related to cellular responses to the types of radiations found in space, with emphasis on comparison of cellular effects from high versus low linear energy transfer (LET) radiations and on effects that might be expected to predominate at the low radiation fluences characteristic of space, e.g., bystander effects and adaptive responses.Conclusions: Space radiation is unique and complex, being composed of galactic cosmic rays and solar particles. Not surprisingly, space radiation biology is also unique and complex. Responses in cells traversed by high atomic number, high energy (HZE) particles are different, at least in part, from the responses of cells exposed to low LET photons not just quantitatively but also qualitatively. This is illustrated by discussion of four sets of data – clustering of DNA damages, foci of DNA repair-related ...
Objective evaluation of the microscopic image sharpness for diagnostic metaphase chromosomes

The purpose of this study is to objectively investigate image sharpness of the metaphase chromosomes at different scanning speeds. In cytogenetic imaging, high scanning speed is sometimes applied to optimize the efficiency. However, at high scanning speed, the obtained image may be deteriorated, due to the scanning blur, under exposure and random vibration of the scanning stage. In this study, the image sharpness of metaphase chromosomes is objectively evaluated. A standard resolution target and several metaphase chromosomes are first imaged under different speeds, by a prototype scanning microscope. Then the sharpness of the acquired images is objectively assessed using a sharpness function. For this prototype system, the results demonstrate that the image sharpness of the metaphase chromosomes is optimized when the scanning speed is 0.8mm/s, under the specified experimental conditions. The results of this study may be useful for optimizing the efficiency and quality of clinical cytogenetic imaging procedures.
Highly turbulent premixed flames stabilied in a co-axial jet flame burner

A co-axial jet flame configuration is found to provide a stable turbulent premixed flame for a wide range of turbulence conditions up to u′/SL of 20 and higher, for an outer to inner diameter ratio of 8 in the current burner. This flame configuration supports premixed flames in flows with initial mean flow velocity in xcess of 150 m/s. Thus, this arrangement can be used for premixed flame stabilization for large flow velocities and for investigations of turbulent premixed flames over a wide range of turbulence properties, with u′/SL exceeding 10 in a steady jet flame. An increase in inner jet velocity increases the turbulence intensity, and a gradual increase in the turbulence intensity from the outer flame to the inner flame acts to stabilize the flames. Flame surface properties such as the flame perimeter ratio and flame curvature statistics are also obtained, where the flame curvature exhibits a nearly symmetric PDF at high turbulence levels in spite of the jet flame geometry.
Direct plasmid mediated transfection of adult murine brain cells in vivo using cationic liposomes

Regional alteration of brain function by directed gene transfer may allow for the investigation and treatment of both inherited and acquired diseases of brain. Examples of inherited CNS diseases that may be investigated by regional gene transfer include the mucopolysaccharidoses (MPS). a group of lysosomal storage diseases characterized by the accumulation of glycosaminoglycans within the neuroglial cells of the CNS [16]. Enzymatic correction directed to the CNS of animals with MPS would allow the analysis of the biochemical, histological and functional effects associated with transgene expression. Further, since metabolic cooperation occurs between various cell types within the brain, a regional correction of MPS deficiency may produce a more diffuse level of biochemical and/or functional improvement. On the other hand, neurodegenerative conditions such as Parkinson's or Alzheimer's are acquired diseases that exhibit a characteristic regional neuropathology, and amelioration of CNS manifestation may result from the regional expression of specific gene products [6,23]. These hypotheses could be tested by the development of methods to mediate the production of transgenic proteins in anatomically defined brain regions. Gene transfer to specific brain regions may be approached by direct somatic cell gene transfer. Since adult mammalian CNS cells do not readily undergo cell division and are long lived, they represent an ideal target for somatic cell gene transfer. Previous efforts at somatic cell
Chronic imaging of amyloid plaques in the live mouse brain using multiphoton microscopy

Transgenic mice expressing the human Amyloid Precursor Protein (APP) develop amyloid plaques as they age. These plaques resemble those found in the human disease. Multiphoton laser scanning microscopy combined with a novel surgical approach was used to measure amyloid plaque dynamics chronically in the cortex of living transgenic mice. Thioflavine S (thioS) was used as a fluorescent marker of amyloid deposits. Multiphoton excitation allowed visualization of amyloid plaques up to 200 micrometers deep into the brain. The surgical site could be imaged repeatedly without overt damage to the tissue, and individual plaques within this volume could be reliably identified over periods of several days to several months. On average, plaque sizes remained constant over time, supporting a model of rapid deposition, followed by relative stability. Alternative reporters for in vivo histology include thiazine red, and FITC-labeled amyloid-(Beta) peptide. We also present examples of multi-color imaging using Hoechst dyes and FITC-labeled tomato lectin. These approaches allow us to observe cell nuclei or microglia simultaneously with amyloid-(Beta) deposits in vivo. Chronic imaging of a variety of reporters in these transgenic mice should provide insight into the dynamics of amyloid-(Beta) activity in the brain.
Short-wavelength gravity lineations and unusual flexure results at the Puka Puka volcanic ridge system

Abstract Short-wavelength gravity lineations aligned parallel to the direction of absolute motion of the Pacific plate, and a newly discovered series of linear, elongate volcanic ridges in the south-central pacific Ocean are just two of the many geophysical and geochemical anomalies that have been observed in this area. These Puka Puka volcanic ridges can be traced for 2600 km along the trough of a major gravity lineation and stretch from close to the East Pacific Rise, in the east, to the Tuamotu Islands in the west. The ridges were the focus of a recent cruise to this area that collected high quality gravity and multi-beam swath bathymetry data, in addition to dredge samples that are suitable for radiometric age dating. A complete 2-D lithospheric flexure analysis of these new data reveals that each of the volcanic ridges is associated with an unusually low effective elastic plate thickness. Previous workers showed this region to be characterised by lower than expected elastic thickness values, which were interpreted in terms of both regional and more localised thermal anomalies in the oceanic lithosphere. The new flexure results obtained for the volcanic ridges in this study confirm these low values. Lithospheric stretching and small-scale convection models that have been put forward to explain the origin of the lineations and volcanic ridges have been re-examined in light of these new results but neither is found to satisfactorily explain all of the observations.
AN IMPROVED TECHNIQUE FOR TRACK PROFILE MEASUREMENT IN NUCLEAR EMULSIONS

Abstract A microdensitometer utilizing a signal averaging digital computer has been developed to discriminate between the charges of particles producing short tracks in nuclear emulsions. For each track the photoelectric profiles of ten track segments, each 5.0 μm long, were averaged and the result plotted, yielding a mean profile curve. Results of measurements made on tracks produced by known particles of charges 1, 2 and 3 are presented. The normalized area of the profile curve was found to give the best charge separation. Measured photometric mean track width values were corrected for the depth of the tracks in the emulsion. The charge groups were completely separated by measurement of 50 μm of each track, requiring less than 15 min per track.
Search for strange quark matter with the BNL-E864 spectrometer

The results of the charged strange quark matter search from central 11.6 A GeV/c Au + Pb collisions in experiment E864 at the BNL-AGS are presented. We have analysed the approximately 6 billion central interactions sampled during the 1995 run for positively and negatively charged strangelet candidates. The results of the 1995 analysis, in which our full calorimeter and high-mass trigger system were used, are nearly three orders of magnitude more sensitive than our 1994 results, and are the best and most model independent sensitivities at AGS energies.
Soybean oil in dried egg mixes

Dried egg mixes prepared commercially with hydrogenated-winterized soybean, corn, or cottonseed oils were evaluated for initial flavor and for flavor storage stability. Quality evaluations were made on products from two processing plants; flavor, color, stability, and mix volumes were determined periodically during storage at 100 F for 1 year. All mixes contained 15% of the specified oil and were air-packaged in 6 oz laminated foil pouches. Replicated triangle flavor tests on reconstituted dried eggs (scrambled) indicated that neither an analytical-type taste panel nor a palatability panel could distinguish between the mixes containing the different vegetable oils. All samples, regardless of oil component, deteriorated at ca. the same rate when stored at elevated temperatures. Minor differences in flavor scores, color indices, and mix volumes were noted in samples stored at 100 F for 9 or 12 months. A dried egg mix made with hydrogenated-winterized soybean oil could not be distiguished, after 4 months’ aging at 100 F, from a fresh (unaged) mix made with corn oil. After 6 months’ storage at 100 F all aged mixes, regardless of the vegetable oil used in their preparation, could be distinguished from the fresh corn oil mix.
Carboxylic acid microbial metabolites of the natural benzoquinone, maesanin

Maesanin (1) is a naturally occurring bioactive benzoquinone isolated from the fruits of Maesa lanceolata (Myrsinaceae). Three carboxylic acid metabolites of maesanin were isolated in the course of a prospective microbial transformation study. The first metabolite, 2, was produced by Lipomyces lipofer ATCC 10742 and was characterized as (Z)-15-(2‘-hydroxy-5‘-methoxy-3‘,6‘-dioxocyclohexa-1‘,4‘-dienyl)pentadec-5-enoic acid. Metabolites 3 and 4 were produced by Rhodotorula rubra ATCC 20129 and were characterized as 6-(2‘-hydroxy-5‘-methoxy-3‘,6‘-dioxocyclohexa-1‘,4‘-dienyl)hexanoic acid and 4-(2‘-hydroxy-5‘-methoxy-3‘,6‘-dioxocyclohexa-1‘,4‘-dienyl)butanoic acid, respectively.
Distribution of larval krill and zooplankton in association with hydrography in Marguerite Bay, Antarctic Peninsula, in austral fall and winter 2001 described using the Video Plankton Recorder

The Western Antarctic Peninsula is a critical locus of Antarctic krill Euphausia superba abundance and thought to be a site of successful overwintering, particularly for the larval stages. A primary goal of the Southern Ocean GLOBEC program was to describe factors that contribute to the overwintering success of krill in this region. As part of this effort we conducted Video Plankton Recorder (VPR) surveys during austral fall and winter, 2001. The VPR survey yielded high-resolution distributions of larval krill, other plankton, and marine snow in relation to hydrography from a series of transect lines orthogonal to the coast on the continental shelf of the Western Antarctic Peninsula. Four taxa (larval krill, copepods, polychaetes, pteropods) and marine snow were numerous during fall; much lower abundances of all categories were present during winter, with only larval krill, copepods, and polychaetes present in any abundance. Distributions of plankton and marine snow were associated with water-mass types and the vertical structure of the environment, particularly for larval krill that were primarily associated with the pycnocline. During fall, larval krill were present across the entire shelf, with high abundances at the shelf break. Copepods were most numerous at depth during fall, consistent with ontogenetic migration to depth at the onset of winter.
Activity of protein kinase C during the differentiation of chick limb bud mesenchymal cells.

Abstract To investigate the relationship between protein kinase C (PKC) and chondrogenesis, PKC activity was assayed in cultures of stage 23/24 chick limb bud mesenchymal cells under various conditions. PKC activities of cytosolic and particulate fractions were low in 1 day cultured cells. As chondrogenesis proceeds, cytosolic PKC activity increased more than twofold, while that of the particulate fraction increased only slightly. Three days' treatment of cultures with phorbol-12-myristate-13-acetate (PMA, 5 × 10−8 M) inhibited chondrogenesis judged by the accumulation of Alcian blue bound to the extracellular matrix and depressed PKC activity in cytosolic fraction. When cells were grown for 3 days in control medium after 3 days' treatment with PMA, chondrogenesis resumed and PKC activity recovered to normal values. PKC activity in cultures plated at low density (2 × 106 cells/ml) where chondrogenesis is reduced was as low as that in 1 day cultured cells plated at high density (2 × 107 cells/ml) or that in PMA treated cells. On the other hand, staurosporine promoted chondrogenesis without affecting PKC activity. Furthermore, reversal of PMA's inhibitory effect on chondrogenesis by staurosporine was not accompanied by recovery of PKC activity. These data indicate that increases in PKC activity is closely related to chondrogenesis and that PMA inhibits chondrogenesis by depressing PKC. However, staurosporine's enhancing effect on chondrogenesis is not related to PKC activity.
Nucleotide sequence and structure of integrated bovine leukemia virus long terminal repeats.

Bovine leukemia virus (BLV) proviruses, harbored by the productively infected fetal lamb kidney (FLK-BLV) cell line, were cloned in bacteriophage lambda L47. The nucleotide sequence of the proviral long terminal repeats (LTR) with flanking cell and virus DNA have been determined. The BLV LTR is 531 bp in length and is bounded by the dinucleotides 5'-TG...CA-3', which are part of a 3-bp inverted repeat. The integrated provirus is flanked by 6-bp direct repeats of cellular DNA. A tRNApro primer binding site is present starting 2 bp downstream of the 5' LTR. In addition to sequencing integrated proviral DNA clones, the nucleotide sequence of a cDNA clone, representing the 3' end of genomic viral RNA, was determined; thus revealing the RNA polyadenylation site and R:U5 boundary within the LTR. Unlike most other retroviruses, a consensus polyadenylation signal, "AATAAA," is not located proximal to the BLV polyadenylation site. The RNA initiation site, defining the U3:R boundary, was located in the BLV LTR by S1 nuclease mapping. This site is approximately 25 bp downstream of an A + T-rich region which probably encompasses a Goldberg-Hogness ("TATAA") box and about 90 bp downstream of a potential "CCAAT" box. The BLV LTR possesses a U3 region of 204 bp, an unusually long R region of 241 bp, and a U5 region of 86 bp.
Lack of association between plasma-renin and history of heart-attack or stroke in patients with essential hypertension.

Abstract The relation between plasma-renin activity and the occurrence of heart-attacks and strokes was examined in 371 Black patients with essential hypertension, who were categorised as having low, normal, or high renin activity according to their 24-hour sodium excretion. The incidence of such complications was found to be identical in each of the renin subgroups. No evidence was found to support the proposal that patients with low renin hypertension are protected against these complications, or that high renin activity is vasculotoxic per se. These findings are not consistent with the view that plasma-renin activity is a potential risk factor in uncomplicated essential hypertension, and emphasise the need for effective therapy in all hypertensive patients regardless of the plasma-renin activity.
A Bayesian Approach to Estimating Decision Parameters in a Replacement Inventory System

This paper deals with the estimation of decision parameters in a special class of inventory systems in which the rate of stock depletion depends on the internal operations of the parent organization instead of market demands. Stocking decisions for this type of inventory systems are unique in that demands for the stocked items are internal demands, sporadic in some instances, infrequent in others, and almost never the direct results of conscious economic decisions. To cope with the peculiar situation, Bayesian point and interval estimation procedures are used. The estimated probability measures provide a basis on which stocking decisions pertinent to this type of inventory systems can be made or evaluated. Specific statistical postulates are made, and a numerical example is given for illustration. The possibility of applying the estimated results to one of the existing inventory models is briefly discussed at the end.
Structural Analysis for the American Airlines Flight 587 Accident Investigation: Global Analysis

NASA Langley Research Center (LaRC) supported the National Transportation Safety Board (NTSB) in the American Airlines Flight 587 accident investigation due to LaRC's expertise in high-fidelity structural analysis and testing of composite structures and materials. A Global Analysis Team from LaRC reviewed the manufacturer s design and certification procedures, developed finite element models and conducted structural analyses, and participated jointly with the NTSB and Airbus in subcomponent tests conducted at Airbus in Hamburg, Germany. The Global Analysis Team identified no significant or obvious deficiencies in the Airbus certification and design methods. Analysis results from the LaRC team indicated that the most-likely failure scenario was failure initiation at the right rear main attachment fitting (lug), followed by an unstable progression of failure of all fin-to-fuselage attachments and separation of the VTP from the aircraft. Additionally, analysis results indicated that failure initiates at the final observed maximum fin loading condition in the accident, when the VTP was subjected to loads that were at minimum 1.92 times the design limit load condition for certification. For certification, the VTP is only required to support loads of 1.5 times design limit load without catastrophic failure. The maximum loading during the accident was shown to significantly exceed the certification requirement. Thus, the structure appeared to perform in a manner consistent with its design and certification, and failure is attributed to VTP loads greater than expected.
Impacts of government policies, economic conditions, and past migration on net migration in the USA: 1992–93

The determinants of net migration rates including government taxes and welfare spending for 48 contiguous states and the District of Columbia during 1992–93 are examined. The weighted least squares (WLS) method is employed assuming dependent variable heteroscedasticity. Major findings indicate that net migration rates vary positively with employment growth, hourly earnings, percentage of possible sunshine, and past net migration, and they are negatively correlated with state and local tax burdens, welfare spending, violent crime, and percentage of population in the age groups of 18–24 and 24–34. Thus, Sir John Hicks's theory that migration was mainly caused by net economic advantages is confirmed. These results may have policy implications in the area of job creation, tax policy, welfare reform, the allocation of limited budget to different programmes and law enforcement.
Spectrographic Electrodes for Refractory Samples

When attempts are made to volatilize completely samples which contain a significant amount of certain refractory oxides in the carbon arc, difficulty is encountered in containing these samples in the electrode. Of the common substances the oxides of calcium and aluminum are the worst offenders. After the more volatile constituents have been driven off, these oxides form a tight bead of very high surface tension, having no tendency to wet the carbon surface, and when this stage is reached the turbulent gas of the arc stream ejects the bead.
Thermal charging effects of Hydrogen in Copper and CuAl alloys

Abstract Thermal charging of hydrogen into copper at 1000°C followed by a rapid quench produces hardening and a slight decrease in the positron Doppler peak parameter P relative to control samples. Deformation of copper after thermal charging of hydrogen produces an extra hardness increase relative to argon as well as an increase in P. In Cu4Al alloy (actual composition, 3.69 wt.% Al and balance copper), thermal charging of hydrogen followed by deformation produces only one-third of the hardness increase produced by thermal charging alone. A slight increase in P is found in the alloy in both deformed and undeformed regions of charged samples. For copper it takes 3 h at 1000°C in hydrogen to observe fully the decrease in P and 4 h in ambient temperature air for the decrease in P to recover. In the Cu4Al alloy, proton pinning of stacking faults results in very effective hardening of annealed material but the protons in this case are not very effective in screening the defects from positrons, presumably because of the low probability of positron trapping close to a proton site in a widely extended fault. In copper, however, protons can quite effectively screen dislocations from detection by positrons. This provides a very effective way of studying hydrogen-defect interactions and hydrogen egress from dislocation traps.
A method for determination of optimal image enhancement for the detection of mammographic abnormalities

We present a paradigm for empirical evaluation of digital image enhancement algorithms for mammography that uses psychophysical methods for implementation and analysis of a clinically relevant detection task. In the experiment, the observer is asked to detect and assign to a quadrant, or indicate the absence of, a simulated mammographic structure characteristic of cancer embedded in a background image of normal breast tissue. Responses are indicated interactively on a computer workstation. The parameter values for the enhancement applied to the composite image may be varied on each trial, and structure detection performance is estimated for each enhancement condition. Preliminary investigations have provided insight into an appropriate viewing duration, and furthermore, suggest that nonradiologists may be used under this methodology for the tasks investigated thus far, for predicting parameter values for clinical investigation. We are presently using this method in evaluating several contrast enhancement algorithms of possible benefit in mammography. These methods enable an objective, clinically relevant evaluation, for the purpose of optimal parameter determination or performance assessment, of digital image-processing methods potentially used in mammography.
Effect of diverse mammalian gonadotropins on estrogen and progesterone production by cultured rat granulosa cells

The ability of gonadotropins from six mammalian species to stimulate estrogen and progesterone production was investigated in granulosa cells of hypophysectomized estrogen-primed immature female rats. Granulosa cells were cultured for 2 days in the presence of delta 4-androstenedione (10(-7) M) with or without various gonadotropin preparations. Treatment with follitropin (follicle-stimulating hormone, FSH) from human, rat, ovine, porcine, equine, and bovine origins resulted in dose-dependent increases in steroidogenesis from negligible amounts to maximal levels of approximately 4-8 and 12-30 ng/10(5) cells for estrogen and progesterone, respectively. The ED50 values of the FSH preparations for stimulation of steroidogenesis were: human: 1-4 ng/ml; ovine: 2.5-30 ng/ml; rat: 1.6-4.0 ng/ml; porcine: 7.5-20 ng/ml; equine 2.5-6 ng/ml; and bovine greater than 100 ng/ml. Lutropin (luteinizing hormone, LH) from rat, ovine, bovine, and porcine origins, human chorionic gonadotropin (hCG), the alpha-subunit of human FSH and the beta-subunit of human LH were ineffective in stimulating steroidogenesis, indicating the specificity of the assay system for FSH. In a high concentration (600 ng/ml), the beta-subunit of human FSH-stimulated steroidogenesis to a small extent. Furthermore, pregnant mare serum gonadotropin and equine LH also caused a dose-dependent stimulation of estrogen and progesterone production, the half-maximal response values (ED50) being 1.8-4 and 7.5-10 ng/ml, respectively. This is consistent with previous in vivo and in vitro findings, showing the potent FSH activities of these hormones. Thus, the cultured rat granulosa cell system provides a sensitive assay for measuring FSH activities of gonadotropins from various mammalian species.
Lost in cyberspace: Barriers to bridging the digital divide in e-politics

In our analysis of e-political participation among a 2003-random sample survey of 478 respondents drawn from Iowa, Pennsylvania and Colorado, six blocks of variables were entered: (1) socio-demographic (2) place effects, (3) voting, (4) technology use (VCR, cell phone, etc.) and computer apathy, (5) attitudes toward technology and (6) specific uses of the internet. In the final block, younger and White respondents are more apt to be e-citizens. Computer training apathy decreases, and IT advantages increase, support for e-citizenry. Seeking medical e-information and making e-purchases increases engagement in e-politics. No main effects of place are found. For Colorado and Iowa residents, less-engaged voters reported less online political engagement, while those who are more likely to vote are also more likely to be advocates of e-politics. The final model explains 56% of the variation in e-government participation.
Characterization of a monoclonal antibody defining a macrophage activation-specific cell surface antigen.

Abstract Macrophages have been obtained from the peritoneal cavities of C57BL/6 mice following treatment with C . parvum , MVE-2, mineral oil, or thioglycollate. Cell populations were primarily composed of mononudear phagocytes as determined by a latex bead uptake assay. Macrophages obtatned from C . parvum or MVE-2 were activated as judged by enhanced cytostatic activity against two tumor cell target lines. Thioglycollate-elicited macrophages demonstrated much lower cytostatic ability. Rats were immunized with activated MVE-2 macrophages. Hybridomas were prepared by fusion with a non-secreting myeloma cell line followed by cloning. Cell supernates were selected on the basis of binding to activated but not elicited macrophages. The monoclonal antibody produced has been characterized by flow cytometry. The antibody does not react with syngeneic erythrocytes, thymocytes, or spleen cells. Reaction with thioglycollate macrophages is very low. Alternatively, intense binding is found on activated macrophages. This antigen which accompanies macrophage activation for tumor ce11 cytostasis is designated as macrophage activation antigen-1 (MAA-1). Several important physiological changes accompany the process of macrophage activation. For example, activated macrophages demonstrate enhanced microbicidal, phagocytic, secretory, and tumoricidal activity (for reviews see refs. 1,2). Concommitant alterations in cell surface properties have been observed. These include: (a) changes in surface morphology and spreading (3–5), (b) altered lipid and protein content (6,7), (c) decreases in 5'-nucleotidase activity and alkaline phosphodiesterase (8), increases in leucine aminopeptidase (8), decreases in mannose receptors (11,12), and antigen F4/80 (11), (d) increases in la antigens (11,12), and (e) increased tumor cell binding (13). These structural and functional modifications indicate that activated macrophages represent a unique class of functionally differentiated cells (9). Antigenic modifications accompanying macrophage differentiation are of special interest. Markers for specific macrophage classes might be useful in defining differentiation pathways, dissecting type-specific functional activities such as tumor cytotoxicity, and providing a means to identify macrophage subsets in heterogeneous cell populations. In the present work we have taken the first step in this direction by defining a cell surface macrophage activation antigen.
The relationship between liquidity, corporate governance, and firm valuation: Evidence from Russia

Abstract This paper examines the hypotheses that liquidity improves corporate governance, and better governance enhances valuation of Russian firms. We find a positive causal relationship between measures of liquidity and corporate governance. Additionally, we document the strong positive impact of corporate governance on valuation. Our results are economically significant. For example, we document that a 10% decrease in the proportion of zero return days implies a 0.34% increase in transparency and disclosure, which in turn leads to a 9.6% increase in firm valuation. Our research findings shed light on the important role of liquidity in improving corporate governance and valuation.
Constitutive Equation of an Al-12.7Si-0.7Mg Alloy in Superplastic Deformation

The hot deformation characteristics of Al-12.7Si-0.7Mg alloy were investigated on an Instron5500 electronic universal testing machine at strain rates ranging from 1.67×10-4 s-1 to 1.67×10-3 s-1 and testing temperatures ranging from 460 °C to 520 °C. The results show that strain rate had a great effect on the flow stress. The flow stress increased with increasing the strain rate. The true stress-strain curves of the Al-12.7Si-0.7Mg alloy were obtained, and the strain rate sensitivity and hot deformation parameters of deformation activation energy were calculated. The hot deformation constitutive equation with hyperbolic sine form was also obtained. The test calculations demonstrate that the constitutive equation describes the deformation features of the Al-12.7Si-0.7Mg alloy well.
Exploring the role of mononuclear phagocytes in the epididymis

The onslaught of foreign antigens carried by spermatozoa into the epididymis, an organ that has not demonstrated immune privilege, a decade or more after the establishment of central immune tolerance presents a unique biological challenge. Historically, the physical confinement of spermatozoa to the epididymal tubule enforced by a tightly interwoven wall of epithelial cells was considered sufficient enough to prevent cross talk between gametes and the immune system and, ultimately, autoimmune destruction. The discovery of an intricate arrangement of mononuclear phagocytes (MPs) comprising dendritic cells and macrophages in the murine epididymis suggests that we may have underestimated the existence of a sophisticated mucosal immune system in the posttesticular environment. This review consolidates our current knowledge of the physiology of MPs in the steady state epididymis and speculates on possible interactions between auto-antigenic spermatozoa, pathogens and the immune system by drawing on what is known about the immune system in the intestinal mucosa. Ultimately, further investigation will provide valuable information regarding the origins of pathologies arising as a result of autoimmune or inflammatory responses in the epididymis, including epididymitis and infertility.
THE THROMBOCYTOPENIA OF CANCER: Prospects for Effective Cytokine Therapy

The previous 10 years have witnessed the development of increasing needs for platelet transfusion in support of aggressive therapies of malignancy. Despite gains in our understanding of platelet preparation, storage, and transfusion, alternative therapies are clearly desirable. During the late 1980s at least six distinct cytokines that display effects on megakaryocyte growth and differentiation-IL-3, KL, GM-CSF, IL-6, IL-11, and LIF- and a synthetic growth factor, PIXY 321, were cloned and characterized. Although none of these cytokines fulfill all of the physiologic roles of thrombopoietin, in its absence several have undergone extensive preclinical and preliminary clinical testing. Of these, IL-11 and PIXY 321 hold promise for clinical amelioration of thrombocytopenia in cancer patients. With the recent cloning of thrombopoietin and its promise in preclinical trials, the role of each of these recombinant proteins in clinical medicine is undergoing careful evaluation. As with erythropoietin and G-CSF before it, given its normal role in the regulation of platelet production, Tpo would appear to provide the greatest physiologic stimulus to platelet production in states of natural and iatrogenic marrow failure. Careful clinical trials of the agent are needed to determine whether the hormone will fulfill this promise. The following decade will most certainly see the resolution of many of the complications of thrombocytopenia and its transfusional support.
Developmental verbal control of behavior: Implications for self-instructional training☆

Abstract Kindergarten, first-grade, and second-grade children (5, 6, and 7 years of age, respectively) performed a Luria-type verbal control task in which motor responses are initiated to positive stimuli and inhibited to negative stimuli. The task was performed by motor responding only and verbal self-directed motor responding, with these conditions reversed in sequence for one half of each grade group. Although motor responding and verbal-motor responding by the two younger groups were generally poor, their performance equalled that of the second graders when the verbalizing condition followed the silent, motor-only condition. For these children, verbalizing appeared to constitute a second task which interfered with motor responding. Prior practice on motor-only responding, however, facilitated subsequent, concurrent performance of the two tasks. No interference or practice effects were found for the second graders. The results suggested that self-instructional training programs are likely to be successful when adequate verbal-motor coordination can be assumed or when the motor response is within the child's repertoire.