cssi/SciSciGPT-SciSciNet huggingface dataset:
Observations on high strain rate crack growth based on a strip yield model

In the past, analytical models have been developed for the study of rapid crack growth in a rate-dependent elastic—plastic material under conditions that permit crack advance in a cleavage mode, and separately for rapid crack advance in an elastic—plastic material when the crack advances by means of a local ductile mechanism. However, models suitable for study of rapid crack growth that permit either mode of crack advance, with the operative mode being determined by which of two competing fracture criteria prevails, have been elusive. Here, the process of dynamic tensile crack growth in a material is studied under small scale yielding conditions with the crack tip plastic zone modeled as a strip yield zone extending ahead of the advancing crack tip. Following Glennie [1] and others, rate dependence of plastic flow is taken into account by assuming that the cohesive stress in the yield zone depends linearly on the local rate of opening of the yield zone. The conditions under which a crack can advance steadily according to either of two criteria are considered. A crack tip opening criterion is identified with a locally ductile mode, and a critical stress condition is identified with a cleavage mode. The analysis leads to conditions among the applied stress intensity factor, the crack speed and the material viscosity that are necessary for sustained crack growth in either case, with the implication that the criterion that is easiest to satisfy will establish the mode by which the crack advances.
Fish oil targets PTEN to regulate NFκB for downregulation of anti-apoptotic genes in breast tumor growth

The molecular mechanism for the beneficial effect of fish oil on breast tumor growth is largely undefined. Using the xenograft model in nude mice, we for the first time report that the fish oil diet significantly increased the level of PTEN protein in the breast tumors. In addition, the fish oil diet attenuated the PI 3 kinase and Akt kinase activity in the tumors leading to significant inhibition of NFκB activation. Fish oil diet also prevented the expression of anti-apoptotic proteins Bcl-2 and Bcl-XL in the breast tumors with concomitant increase in caspase 3 activity. To extend these findings we tested the functional effects of DHA and EPA, the two active ω-3 fatty acids of fish oil, on cultured MDA MB-231 cells. In agreement with our in vivo data, DHA and EPA treatment increased PTEN mRNA and protein expression and inhibited the phosphorylation of p65 subunit of NFκB in MDA MB-231 cells. Furthermore, DHA and EPA reduced expression of Bcl-2 and Bcl-XL. NFκB DNA binding activity and NFκB-dependent transcription of Bcl-2 and Bcl-XL genes were also prevented by DHA and EPA treatment. Finally, we showed that PTEN expression significantly inhibited NFκB-dependent transcription of Bcl-2 and Bcl-XL genes. Taken together, our data reveals a novel signaling pathway linking the fish oil diet to increased PTEN expression that attenuates the growth promoting signals and augments the apoptotic signals, resulting in breast tumor regression.
Studies on the Structure, Regulation, and Pathogenic Potential of Anti-dsDNA Antibodies

Studies of anti-double-stranded (anti-ds)DNA antibodies have provided insights into how and why these antibodies arise in systemic lupus erythematosus. In this review we discuss the experimental approaches that have been used by our laboratory to study these autoantibodies. Structure/function analyses including site-directed mutagenesis have helped characterize the molecular genetics of anti-dsDNA antibodies, and more recently peptide libraries have been used to define molecular motifs that these antibodies bind. Most of the pathogenic anti-dsDNA antibodies observed in lupus are somatically mutated. We demonstrated in vitro and in vivo that anti-bacterial antibodies can mutate to acquire specificity for dsDNA. Furthermore, using a fusion partner constitutively expressing bcl-2, NSO(bcl-2), we have shown the existence of anergic or preapoptotic B cells making antibodies that cross-react with both bacterial antigen and dsDNA. Whether defects in the regulation of these antibodies might contribute to serum expression of anti-dsDNA antibodies in some individuals remains unknown. A major emphasis of this review is the regulation of anti-dsDNA antibodies in a transgenic mouse model harboring the gene for the heavy chain of a pathogenic anti-dsDNA antibody. Nonautoimmune transgenic mice effectively regulate autoreactive B cells by anergy and deletion, while their autoimmune counterparts do not. The vast majority of anergic B cells expressing high-affinity transgenic anti-dsDNA antibody fail to display allelic exclusion of the heavy chain. We postulate that this may be one mechanism that allows them to escape deletion. Comparative studies on light chain usage in both the autoimmune and the nonautoimmune transgenic mouse strains have demonstrated that within the autoreactive B-cell population, there are subsets that are differentially regulated. Ultimately transgenic animals making pathogenic autoantibodies may provide us with a system for testing novel therapies for autoimmune disease.
Neuronal activity of the locus ceruleus in awake Macaca arctoides

Neuronal activity in the locus ceruleus of awake, behaving stump-tailed monkeys increased consistently and vigorously after presentation of mildly aversive and threatening stimuli. These preliminary data increase the range of stimuli reported to elicit locus ceruleus activity in awake monkeys to include nonpainful threat signals and suggest that more studies are needed to be able to categorize locus ceruleus function from its unit activity responses.
Community-Level Successes and Challenges to Implementing Adolescent Sex Education Programs

Best practices for adolescent sex education recommend science-based approaches. However, little is known about the capacity and needs of organizations who implement sex education programs on the local level. The purpose of this research was to describe successes and challenges of community organizations in implementing science-based sex education. Using qualitative methods, we interviewed program directors and educators in 17 state-funded adolescent pregnancy prevention/sex education programs as part of a larger mixed methods evaluation. Semi-structured interviews focused on success and challenges faced in implementing science-based approaches to program design, implementation and evaluation. Interviews were audio-recorded, transcribed and analyzed using a thematic approach. Grantees included a range of programs, from short programs on puberty and HIV for late elementary students, to skills-based curricular sex education programs for high schools, to year-long youth development programs. Key aspects of curricular choice included meeting the needs of the population, and working within time constraints of schools and other community partners. Populations presenting specific challenges included rural youth, youth in juvenile justice facilities, and working with Indiana’s growing Latino population. Programs self-developing curricula described challenges related to assessment and evaluation of impact. Programs using commercial curricula described challenges related to curricular selection and adaptation, in particularly shortening curricula, and adapting to different cultural or social groups. A remarkable degree of innovation was observed. The use of qualitative methods permitted the identification of key challenges and successes in a state-sponsored small grants program. Information can be used to enhance program capacity and quality.
Pretransplant Screening for the Development of Posttransplant Diabetes Mellitus (PTDM) † 478

Pretransplant Screening for the Development of Posttransplant Diabetes Mellitus (PTDM) † 478
Variational methods in materials sciences

The variational study of material instabilities such as phase transitions, the formation of defects in crystalline materials, the onset of microstructure and the development of fractures, has needed new mathematical techniques since the problems involved generally escape the old theories. Some of the analytical progress that has been made recently towards the understanding of these phenomena is outlined.
The N-terminus of hepcidin is essential for its interaction with ferroportin: structure-function study

Hepcidin is the principal iron-regulatory hormone. It acts by binding to the iron exporter ferroportin, inducing its internalization and degradation, thereby blocking cellular iron efflux. The bioactive 25 amino acid (aa) peptide has a hairpin structure stabilized by 4 disulfide bonds. We synthesized a series of hepcidin derivatives and determined their bioactivity in a cell line expressing ferroportin-GFP fusion protein, by measuring the degradation of ferroportin-GFP and the accumulation of ferritin after peptide treatment. Bioactivity was also assayed in mice by the induction of hypoferremia. Serial deletion of N-terminal amino acids caused progressive decrease in activity which was completely lost when 5 N-terminal aa's were deleted. Synthetic 3-aa and 6-aa N-terminal peptides alone, however, did not internalize ferroportin and did not interfere with ferroportin internalization by native hepcidin. Deletion of 2 C-terminal aa's did not affect peptide activity. Removal of individual disulfide bonds by pairwise substitution of cysteines with alanines also did not affect peptide activity in vitro. However, these peptides were less active in vivo, likely because of their decreased stability in circulation. G71D and K83R, substitutions previously described in humans, did not affect hepcidin activity. Apart from the essential nature of the N-terminus, hepcidin structure appears permissive for mutations.
Visual search by action category

Humans are sensitive to different categories of actions due to their importance in social interactions. However, biological motion research has been heavily tilted toward the use of walking figures. Employing point-light animations (PLAs) derived from motion capture data, we investigated how different activities (boxing, dancing, running, and walking) related to each other during action perception, using a visual search task. We found that differentiating between actions requires attention in general. However, a search asymmetry was revealed between boxers and walkers, i.e., searching for a boxer among walkers is more efficient than searching for a walker among boxers, suggesting the existence of a critical feature for categorizing these two actions. The similarities among the various actions were derived from hierarchical clustering of search slopes. Walking and running proved to be most related, followed by dancing and then boxing. Signal detection theory was used to conduct a non-parametric ROC analysis, revealing that human performance in visual search is not fully explained by low-level motion information.
Effect of Insertion of a Heat Flux Gage Into a High Temperature Cylindrical Blackbody Cavity on the Gage

Detailed transient thermal models have been developed to simulate a heat flux gage calibration process capable of generating high heat flux levels. These heat flux levels are of interest to the reciprocating and gas turbine engine industries as well as the aerospace industry. The transient models are based on existing, experimentally validated steady state models of a cylindrical blackbody calibration system. The steady state models were modified to include insertion of a heat flux gage into the hot zone of the calibration system, time-varying electrical current that passes through the resistance heated blackbody, and the resulting heating of the heat flux gage. Heat fluxes computed using detailed transient models were compared to experimental measurements. The calculated and measured transient heat fluxes agreed to within 2 percent, indicating that the models had captured the physical phenomena in the transient calibration. The predicted and measured transient heat fluxes were also compared for two different blackbody configurations. The effect of convection on the blackbody extension was evaluated and found to be a minor factor.
Research directions in travel demand analysis

Because of the wide applicability of choice modeling techniques, Horowitz's paper implies that this research could be expected to yield benefits extending far beyond the transportation community. This paper builds upon a number of issues raised in the Horowitz's review and makes several additional observations. The problem of data inadequacy is examined in the second section. Lack of data is seen not only as an impediment to further progress on techniques for choice modeling but also as a restriction on the exploration of new hypotheses about travel behaviour. It is argued that a carefully-conceived data collection effort is a neccessary prerequisite to progress in travel demand theory. For paper by Horowitz see IRRD 287445.
ELASTOGRAPHIC IMAGING OF THERMAL LESIONS IN THE LIVER IN VIVO FOLLOWING RADIOFREQUENCY ABLATION: PRELIMINARY RESULTS

Radiofrequency (RF) ablation is an interstitial focal ablative therapy that can be used in a percutaneous fashion. This modality provides in situ destruction of hepatic tumors. However, local recurrence rates after RF ablative therapy are as high as 34% to 55%, believed to be due in part to the inability to visualize accurately the zone of necrosis (thermal lesion). This can lead to the incomplete ablation of the tumor, generally in areas near the tumor edges. In this paper, we show that ultrasound (US)-based in vivo elastography can accurately depict thermal lesions after thermal therapy. However, elastography of the liver and other abdominal organs is challenging due to the difficulty in providing controlled and reproducible compression. The use of the RF ablation probe as the compressor/displacement device reduces lateral slippage or nonaxial motion that may occur with externally applied compressions or imaging during the respiratory cycle. This technique also provides controlled and reproducible compressions of the liver for in vivo elastographic imaging. Comparison of elastograms with histology of ablated tissue demonstrates a close relationship between elastographic image features and histopathology.
Relative Contributions of Naturalistic and Constructed Support: Two Studies of Women with Type 2 Diabetes

Do distinct sources of social support have differential effects on health? Although previous research has contrasted family and friend support (naturalistic support), research on the relative effects of naturalistic support and constructed support (e.g., support groups) is extremely rare. Two studies of women with type 2 diabetes were conducted that assessed the independent effects of naturalistic and constructed support on physical activity and glycosylated hemoglobin (HbA1c). Participants were women diagnosed with type 2 diabetes from the intervention arms of two randomized controlled trials: primarily European American women (Study 1; N = 163) and exclusively Hispanic women (Study 2; N = 142). Measures assessed physical activity, HbA1c, and friend and family support at baseline and at 6 months, as well as group support after 6 months of intervention. In Study 1, only group support was related to increases in physical activity (ΔR2 = .036). In Study 2, group support and family support showed independent effects on increases in physical activity (ΔR2 = .047 and .060, respectively). Also, group support was related to decreases in HbA1c in Study 1 (ΔR2 = .031) and Study 2 (ΔR2 = .065). Overall, constructed (group) support was related to outcomes most consistently, but naturalistic (family) support showed some independent relation to physical activity improvement.
Children of Seropositive Mothers in the U.S. AIDS Epidemic

Seven to ten thousand American children are orphaned each year when their mothers die from AIDS. AIDS-affected families with children have four acute needs. First, many parents with AIDS are indigent with no prospect of employment, and need welfare or disability-based income support. Second, parents need accessible and affordable health care for themselves and their children. Third, parents need legal services to secure the custody and guardianship of their children. Finally, many orphaned children require placements in homes through foster care and adoptive systems. Current legislative initiatives have proposed to change federal entitlement spending programs in ways that could make it less likely that AIDS-affected families would receive these safety-net services.
Real-time monitoring of laser hot-wire cladding of Inconel 625

Abstract Laser hot-wire cladding (LHWC), characterized by resistance heating of the wire, largely increases the productivity and saves the laser energy. However, the main issue of applying this method is the occurrence of arcing which causes spatters and affects the stability of the process. In this study, an optical spectrometer was used for real-time monitoring of the LHWC process. The corresponding plasma intensity was analyzed under various operating conditions. The electron temperature of the plasma was calculated for elements of nickel and chromium that mainly comprised the plasma plume. There was a correlation between the electron temperature and the stability of the process. The characteristics of the resulted clad were also investigated by measuring the dilution, hardness and microstructure.
Statistical analysis of acoustic measurements for assessing pavement surface condition

This work presents a method for assessing pavement surface condition using measurements from a microphone mounted underneath a moving vehicle. Such measurements will include tire-generated sound, which carries much information about the road condition, as well as noise generated by the wind and vehicle. The proposed method uses Principal Component Analysis (PCA) to extract the tire-generated sound from the noisy measurements. The analysis begins with acoustic pressure measurements made over constant and known road conditions. Fourier transforms are taken over various time windows and a PCA is performed over the resulting vectors, yielding to a set of principal component vectors for that road condition. Each road condition is characterized by a set of principal component vectors. These vector sets are used to analyze measurements from a road with unknown road conditions by finding the vector set that best represents the acoustic measurements from that road. Successful applications of this method are demonstrated by accurate estimations of the mean texture depth (MTD) of pavement directly from acoustic measurements.
Library Orientation and Instruction—1987

The following is an annotated list of materials dealing with orientation to library facilities and services, instruction in the use of information resources, and research and computer skills that are related to retrieving and using information. This is the fourteenth review to be published in Reference Services Review and lists items in English published in 1987. A few items are not annotated because the compiler could not obtain copies of them for this review.
Structure determination with HREELS and LEED: The molecular structure of chemisorbed benzene on Pd(111)

Abstract The combination of HREELS (high-resolution electron energy-loss spectroscopy) and LEED (low-energy electron diffraction) has been successfully applied to study complicated coadsorption structures of benzene and CO on various transition metal surfaces. Through these studies, different benzene structures have emerged depending on the substrate metal. Recent work concerns coadsorption of benzene and CO on Pd(111), where an almost gas-phase like benzene structure has been detected.
Scanning electrochemical microscopy of membrane transport in the reverse imaging mode.

Scanning electrochemical microscopy (SECM), operated in reverse imaging mode (RIM), has been used to visualize the steady-state transport of molecules entering into porous membranes. RIM imaging is advantageous for investigating transport across biological membranes in situations where the SECM tip can access only the exterior membrane surface. Examples of RIM images of a synthetic membrane (mica with pores filled with the ion-selective polymer Nafion) and a biological membrane (hairless mouse skin) recorded during diffusive and iontophoretic transport, are reported. RIM imaging during diffusive transport allows visualization of the depletion of solute molecules in the solution adjacent to the pore openings. However, an accumulation of solute molecules above the pore opening is observed during iontophoresis, which is a consequence of the separation of the solute from the solvent (i.e., ultrafiltration). The separation results from differences in the rates of molecule transfer across the pore/solution interface when electroosmotic flow is operative. The results suggest that RIM imaging may be useful for measuring the kinetics of interfacial molecule transfer at biological membranes.
Protecting Civilians…or Soldiers? Humanitarian Law and the Economy of Risk in Iraq

The level of non-combatant casualties in modern Western warfare is determined in large part by the way in which policymakers apportion risk between soldiers and civilians. In the U.S. counterinsurgency in Iraq, a “kinetic” strategy and a muscular doctrine of force protection have lowered the threshold for the use of violence and, in many cases, transferred risk from soldiers to civilians. Particularly in areas deemed hostile, aggressive tactics make up for a shortage of soldiers on the ground and direct violence toward non-combatants. This is not the fog of war: even unintended civilian casualties flow predictably from policy choices. Perceptions of risk increasingly govern U.S. interpretations of its humanitarian obligations under international law, threatening to dilute the doctrine of proportionality and reverse the customary and legal relationship between combatants and non-combatants. Only late in the war has the U.S. administration recalibrated risks and launched a more orthodox counterinsurgency strategy.
The role of strongly interface/surface adsorbed impurities on the purification process via crystallization methods

Abstract This paper focuses first on the differences in impurity partitioning during crystallization between the case where the adsorbed impurity is interface mobile and does not upset the interface partitioning via altering the driving force needed for the molecular attachment part of the overall crystallization process and the case where the molecular attachment kinetics are strongly altered by the adsorption process. These considerations are then applied to crystals of both elemental materials and AB compounds where, for the latter, it can be shown that the differential molecular factors between A and B always lead to non-stoichiometric crystals and that some adsorption examples can greatly accentuate this effect. Finally, some cases of severe adsorption strongly favor the formation of a filamentary interface which significantly decreases the efficiency of the purification process.
Using Metaphors to Uncover the Selves in my Practice

This study describes how one teacher educator used metaphor as a self-study tool over an eight-year period. Several methods of eliciting metaphors are discussed and the effects of multiple metaphors on the educator's perspectives on practice are highlighted. The interplay among the metaphors and their meaning is described and used to provide additional insights. The work demonstrates how long-term use of metaphors can be a way to step back from practice, take a new look at the meaning of the particulars of practice, and reframe events of practice. Potential avenues for improvement of practice emerged from these interpretations, and the effects of these changes and possible future efforts are discussed.
Does race affect readmission to hospital after critical illness

Objective To examine the influence of race on 7-day hospital readmission rates after discharge of critically ill patients. Methods Racial status is a risk factor for early (within 7 days) hospital readmission after initial recovery from critical illness and respiratory failure. This was a retrospective cohort study that took place in a 350-bed community hospital. Adult patients who received mechanical ventilation during their intensive care unit stay were included. Study subjects were categorized as white, black (non-Hispanic), Hispanic, and Asian/other. The main outcome measure was readmission to the hospital within 7 days of discharge. Secondary outcomes were hospital mortality and durations of hospital and intensive care unit stay. Comparisons were made across racial groups. Results Of 772 patients, 172 (22.3%) died, and 96 of the 591 discharged patients (16.2%) were readmitted within 7 days. Race was not a determinant of rapid readmission: 11.6% of blacks ( P = . 2), 20.6% of Hispanics ( P = . 3) and 16.5% of whites were readmitted within 7 days. Readmitted patients were more likely to have been discharged to a rehabilitation or extended care facility rather than to home (22.1% vs 2.2%, P P = . 004), to be aged ≥ 80 years (24.4% vs 13.9%, P = . 005), and to be female (19.5% vs 13.7%, P = . 04). Multivariate logistic regression analyses demonstrated that discharge to a place other than home (odds ratio 10.1, 95% confidence interval 3.6–28.3) and prolonged duration of mechanical ventilation (odds ratio 2.8, 95% confidence interval 1.1–6.9) were independently associated with readmission. Race did not significantly influence in-hospital mortality. Overall, the deceased were older and more likely to be female, and had longer durations of mechanical ventilation and medical and surgical intensive care unit stays. Conclusion Contrary to our hypothesis, race was not associated with rapid readmission or mortality of critically ill patients. Factors independently associated with rapid readmission were mechanical ventilation beyond 29 days and disposition to an acute rehabilitation or skilled nursing facility. Further studies are required to ascertain whether these factors are generalizable or idiosyncratic to our institution.
Interferometric Measurement of the Angular Sizes of Dwarf Stars in the Spectral Range K3-M4

We have used the Palomar Testbed Interferometer to measure the angular diameter of five dwarf stars of spectral types K3-M4. Using the 110 m baseline and observing in H and K bands allows us to measure angular diameters with an accuracy of 2%-8% for stars with apparent angular diameters approaching 1 milliarcsecond. We provide results for both uniform-disk and limb-darkened models and compare our results with theoretical predictions. At the current level of precision our measurements are consistent with most widely accepted models, but further observations should be able to provide useful empirical constraints.
Energy levels of rare earth ions in cubic crystal fields

Abstract Cubic crystal field Stark splittings have been calculated for the lowest term of the rare earth ions Ce 3+ through Sm 3+ and Tb 3+ through Yb 3+ for combined fourth and sixth order potentials. Energy level diagrams corresponding to eightfold coordination are given for seven choices of the ratio of sixth to fourth order terms, ranging from pure fourth order field to about five times the ratio to be expected on a point charge model. The splittings in different ions are compared on the assumption that the crystal field intensities and the expectation values for the fourth and sixth powers of the rare earth f -electron radius vary smoothly through the rare earth series. Experimental information on garnets suggests that the ratio of sixth to fourth order terms is about twice that to be expected on a point charge model for these crystals. For this ratio there is a marked tendency in ions to the right of gadolinium for the crystal field levels to cluster into two groups separated by a gap large compared with the spacings within each group. The total Stark splitting is found to be of comparable magnitude for all the rare earth ions, with somewhat larger values at the ends of the series than in the middle.
Osmotic Properties of Aqueous Solutions Containing Caffeine

An improved form of the thermoelectric osmometer developed by one of the authors has been used to study solutions of p -aminobenzoic acid, citric acid, sodium citrate, sodium salicylate, sodium benzoate, morphine hydrochloride, and papaverine hydrochloride alone and in combination with caffeine. The measured colligative property is plotted against concentration of caffeine. These data are described by two intersecting straight lines for each substance. The point of intersection occurs at different positions on the caffeine scale depending upon the nature and concentration of the complexing agent. The shift along the caffeine scale from the break in the pure caffeine data is divided by the concentration of the complexing agent to give a characteristic complexing capacity number. Osmotic coefficients may be calculated from tabulated slopes.
The isotopic composition of uranium and lead in Allende inclusions and meteoritic phosphates

We measured the isotopic compositions of U and Pb in eight Ca-Al-rich inclusions from the Allende chondrite, in whitlockite from the St. Severin chondrite, and in a whitlockite and a whole rock sample from the Angra dos Reis achondrite (ADOR). The total range in ^(235)U/^(238)U in the acid-soluble phases of the Allende inclusions and meteoritic whitlockites is from 1/137.6 to 1/138.3, and to within the error limits (3–20‰) indistinguishable from normal terrestrial U. The ^(235)U/^(238)U ratios for whitlockites from St. Severin and ADOR are the same as that in the bulk meteorites and are normal. The Pb isotopic compositions of the acid-soluble phases of the Allende coarse-grained inclusions (except C-1) give a mean ^(207)Pb/^(206)Pb model age of4.559 ± 0.015AE which is consistent with the observation of normal U isotopic composition. The Pb isotopic compositions of coarse-grained (FUN) inclusion, C-1, and of two fine-grained inclusions from Allende indicate that the U-Pb systems of these samples have evolved differently from the rest of the meteorite. The ^(207)Pb/^(206)Pb model ages for the whitlockites and for bulk ADOR are the same as those for St. Severin whitlockite,4.551 ± 0.004AE. The Pb results from St. Severin indirectly constrain the value of the U isotopic abundance to be within 7.4‰ of normal. Both the directly measured235U/238U and the Pb data on St. Severin are in complete disagreement with claims of large ^(235)U excess reported by other workers on the same meteorite. The Th/U ratios of some acid-soluble phases of Allende inclusions and of meteoritic whitlockite show varying degrees of enrichment of Th relative to U by factors of 2 to 25 relative to the bulk meteorites. Previous studies have shown that ^(244)Pu/^(238)U ratios in whitlockite are also fractionated relative to the bulk meteorites. The observation of no isotopic effects in U reported here does not support the claims of either fractionation of ^(247)Cm/^(238)U or of a large amount of live ^(247)Cm at the early stage of formation of the solar system. Using the present data we obtain a limit of ^(247)Cm/^(235) U≤ 4 × 10^(−3) at the time of meteorite formation or differentiation. This implies that the last major “r” process contribution to the material in the protosolar nebula was ∼10^8 years prior to ^(26)Al formation and injection.
Multidisciplinary contributions from crystal chemical and geochemical studies: The 2002 Benjamin Franklin Medal in earth science presented to Alexandra Navrotsky

Dr. Alexandra Navrotsky is currently a Faculty Member at the University of California, Davis, and holds a joint appointment in the Departments of Chemical Engineering; Materials Science; Chemistry; Geology; and Land, Air and Water Resources. Dr. Alexandra Navrotsky is being awarded a Franklin Medal for her work in crystal chemistry and in many different allied disciplines. Just the enormous volume of her accomplishments is award worthy. At press time she has 370 journal papers, 15 written, reviewed and/or edited books and 51 review papers and/or book chapters. Dr. Navrotsky has contributed thermodynamic data on hundreds of binary and ternary compounds, has generalized these data into concepts of bonding energies, and has used physics and chemistry to importantly contribute insights into ceramics, metallurgy, materials research, mantle petrology and, of course, crystal chemistry.
Purinergic modulation of ethanol-induced sleep time in long-sleep and short-sleep mice.

The long-sleep (LS) and short-sleep (SS) mice were selectively bred for differences in sensitivity to the depressant effects of ethanol. In addition to their differential sensitivity to ethanol, they are also differentially sensitive to purinergic agonists and antagonists. This suggests that there may be differences in the purinergic systems of these lines of mice which may aid in understanding how they differ in ethanol sensitivity. We have investigated whether these drugs are capable of modifying acute ethanol sensitivity as measured by ethanol-induced loss of the righting response (ethanol sleep time), waking blood and brain ethanol concentrations, and blood ethanol elimination rate. The purinergic agonists cyclohexyladenosine (CHA), l-phenylisopropyladenosine (PIA), 2-chloroadenosine (CAD), and N-ethylcarboxamidoadenosine (NEC) increased sleep time in both LS and SS mice, however, LS mice were generally more affected than SS. The LS and SS mice were also differentially sensitive to the purinergic antagonists, theophylline and caffeine. Blood and brain ethanol concentration on awakening suggested that CNS sensitivity to acute ethanol administration was altered by pretreatment with agonists but not antagonists. Two agonists, CHA and NEC, significantly lowered ethanol elimination in both lines of mice while PIA, CAD, and the antagonists theophylline, and caffeine were without affect on elimination rate. These data support previous observations that adenosine-mediated systems may be involved in the modulation of ethanol sensitivity.
Traumatic brain injury induces neuroinflammation and neuronal degeneration that is associated with escalated alcohol self-administration in rats.

Background Traumatic brain injury (TBI) affects millions of people each year and is characterized by direct tissue injury followed by a neuroinflammatory response. The post-TBI recovery period can be associated with a negative emotional state characterized by alterations in affective behaviors implicated in the development of Alcohol Use Disorder in humans. The aim of this study was to test the hypothesis that post-TBI neuroinflammation is associated with behavioral dysfunction, including escalated alcohol intake.
The M4 muscarinic receptor-selective effects on keratinocyte crawling locomotion

We have investigated how the cholinergic system of epidermal keratinocytes (KC) controls migratory function of these cells. Several molecular subtypes of muscarinic acetylcholine receptors (mAChRs) have been detected in KC. Early results suggested that M4 is the predominant mAChR regulating cell motility. To determine muscarinic effects on lateral migration of KC, we used an agarose gel keratinocyte outgrowth system (AGKOS) which provides for measurements of the response of large cell populations (> 104 cells). Muscarine produced a dose-dependent stimulatory effect on cell migration (p < 0.05). This activity was abolished by atropine, which decreased migration distance when given alone. To identify the mAChR subtype(s) mediating these muscarinic effects, we substituted atropine with subtype-selective antagonists. Tropicamide (M4-selective) was more effective at decreasing the migration distance than pirenzepine and 4-DAMP at nanomolar concentrations. We then compared lateral migration of KC obtained from M4 mAChR knockout mice with that of wild-type murine KC, using AGKOS. In the absence of M4 mAChR, the migration distance of KC was significantly (p < 0.05) decreased. These results indicate that the M4 mAChR plays a central role in mediating cholinergic control of keratinocyte migration by endogenous acetylcholine produced by these cells.
The dynamics of precipitate evolution in elastically stressed solids—I. Inverse coarsening

The effects of elastic stress generated by a misfit between a particle and matrix on the morphological evolution of a two-phase microstructure have been investigated. The particles were allowed to evolve by the flow of mass through the matrix with the interfacial concentrations given by the elastic stress-modified Gibbs-Thompson equation. We find that neither the total elastic nor the total interfacial energy must decrease with time during the evolution of the particles. Two misfitting particles were never observed to be stable with respect to coarsening, in contrast to the predictions of energetic calculations using particles of fixed morphology. However, inverse coarsening, wherein a small particle grows at the expense of a large particle, was quite common in systems with more than two particles. This inverse coarsening process can, in some cases, be accompanied by a decrease in the total interfacial energy in the system. We also find that particles which are aligned along the elastically soft directions of the crystal can evolve by the flow of mass through the thin regions of matrix separating these particles.
The FKG Inequality for Partially Ordered Algebras

The FKG inequality asserts that for a distributive lattice with log-supermodular probability measure, any two increasing functions are positively correlated. In this paper we extend this result to functions with values in partially ordered algebras, such as algebras of matrices and polynomials.
Spindle checkpoint component Mad2 contributes to biorientation of homologous chromosomes.

Abstract Cell cycle checkpoints sense defects in chromosome metabolism, halt the cell cycle, and activate pathways that repair the defects. The spindle checkpoint arrests the cell cycle in response to defects in the interaction between microtubules and kinetochores (the proteinaceous complex assembled on centromeric DNA), but no repair function has been demonstrated for this checkpoint. We show that the roles of two spindle checkpoint components, Mad2 and Mad3, differ in meiosis I. In the absence of Mad2, meiosis I nondisjunction occurs at a high frequency and can be corrected by delaying the onset of anaphase [1]. The absence of Mad3 does not induce nondisjunction, even though mad3 Δ cells cannot arrest the cell cycle in response to kinetochores that lack either microtubules or tension on the linkage between chromosomes and microtubules. The two proteins have different roles in chromosome alignment. Compared to wild type and mad3 Δ cells, mad2 Δ mutants are slower to attach homologous chromosomes to opposite poles of the spindle. This observation suggests that Mad2 plays a role in reorienting chromosomes that are incorrectly attached to the spindle as well as delaying the cell cycle, whereas Mad3 is needed for the cell cycle delay, but not for chromosome reorientation.
A MAC protocol to support QoS for multimedia traffic transmission over ad hoc networks

Multimedia communication over wireless networks has become the driving technology for many important applications, experiencing dramatic market growth and promising revolutionary experiences in personal communication, gaming, entertainment, military, security, environment monitoring, and more. The advances in wireless communications and growth of real-time applications have necessitated the development of wireless networks that can support high Quality of Service (QoS). In this paper, we introduce a reservation based, asynchronous MAC protocol called Multi-rate Multi-hop MAC Protocol (MMMP) for multi-hop Ad hoc networks that provides QoS guarantees for multimedia traffic. MMMP achieves this by providing service differentiation for multi-rate real-time traffic (both real time constant bit rate traffic and real time variable bit rate traffic) and guaranteeing a bounded end-to-end delay for the same while still catering to the throughput requirements of non real time traffic. In addition, it administers bandwidth preservation via a feature called 'Smart Drop' and implements efficient bandwidth usage through a mechanism called 'Release Bandwidth'. Simulation results on the QualNet simulator indicate that MMMP outperforms IEEE 802.11 on all performance metrics and can efficiently handle a large range of traffic intensity. It also outperforms other similar state of the art MAC protocols.
Behavior Evolution and Event-Driven Growth Dynamics in Social Networks

In many social networks, the connections between actors are formed because they participate in the same event, such as a set of scholars coauthoring a paper and a person making phone calls or having teleconferences with his friends. Therefore, we propose an event-driven framework for creating network growth models. We also notice that in evolving networks, both the behavior of the whole network and the behavior of nodes evolve over time. For example, we observe in collaborative networks that the growth rates of the communities and the average number of coauthors in papers change as the network sizes increase over time, and researchers' interactions with local groups and remote groups also evolve over time with their experience (degree). These observations motivate us to propose a behavior evolution-aware event-driven locality and attachedness based model to capture the growth dynamics in social networks. Based on some informative metrics of network structure and properties, such as degree distribution, degree-dependent clustering coefficients, and degree-dependent average degree of neighbors, the experiments suggest that our model can better characterize the growing process and simulate important network structures observed in real networks than other non-event driven and non-behavior aware models.
1167 A NEUROMUSCULAR MECHANISM PREVENTING AIRWAY OBSTRUCTION

To function as a conduit for air, the extrathoracic airway (ETA) must resist closure when intraluminal pressure decreases during inspiration. Previous work (Fed. Proc., in press) suggested that a neuromuscular mechanism opposes ETA closure. Current experiments elucidate this mechanism. The ETA segment most vulnerable to passive closure was determined. Closing pressure (CP) was defined as that negative intraluminal pressure at which pressure changes are no longer transmitted across the ETA. In 5 rabbits, 30-32 days old, post mortem CP of the ETA was -6.0 ± 1.8 cm H2O; in each case, the nose and trachea remained open at -40 cm H2O, thus implicating the pharynx or larynx as the site of closure. In anesthetized rabbits, forward inspiratory movement of the hyoid bone and associated soft tissues was observed. Electromyography of muscles which pull the hyoid and tongue forward (mylohyoid, geniohyoid, genioglossus) demonstrated phasic inspiratory activity which increased during asphyxia from airway occlusion. Post mortem, the action of these muscles was simulated by traction on the hyoid. CP of the ETA with hyoid traction was -14.2 ± 3.1 cm H2O compared to -6.0 ± 1.8 cm H2O without traction (N=5, p <.01, paired t-test). This difference in CP with and without traction suggests that the mylohyoid, geniohyoid and genioglossus muscles function as accessory muscles of respiration to prevent inspiratory airway obstruction.
Assessing population-level variation in the mitochondrial genome of Euphausia superba using 454 next-generation sequencing

The Antarctic krill (Euphausia superba Dana 1852) is widely distributed throughout the Southern Ocean, where it provides a key link between primary producers and upper trophic levels and supports a major commercial fishery. Despite its ecological and commercial importance, genetic population structure of the Antarctic krill remains poorly described. In an attempt to illuminate genetic markers for future population and phylogenetic analysis, five E. superba mitogenomes, from samples collected west of the Antarctic Peninsula, were sequenced using new 454 next-generation sequencing techniques. The sequences, of lengths between 13,310 and 13,326 base pairs, were then analyzed in the context of two previously-published near-complete sequences. Sequences revealed relatively well-conserved partial mitochondrial genomes which included complete sequences for 11 of 13 protein-coding genes, 16 of 23 tRNAs, and the large ribosomal subunit. Partial sequences were also recovered for cox1 and the small ribosomal subunit. Sequence analysis suggested that the cox2, nad5, and nad6 genes would be the best candidates for future population genetics analyses, due to their high number of variable sites. Future work to reveal the noncoding control region remains.
Platelet-derived growth factor prevents G0 growth arrest

Baserga1 has summarised evidence that there are two growth states in which cells have a diploid content of DNA; G1—the interval between mitosis and S phase in exponentially growing cultures—and G0, a quiescent state entered only when conditions for growth are suboptimal. G0 can be distinguished from G1 by temporal measurements; for BALB/c 3T3 cells, the lag time between G0 and S phase is never shorter than 12 h (ref. 2), whereas in exponentially growing cells the mean lag time between mitosis and S (G1 by definition) lasts 5–6 h (ref. 3). G0 can also be distinguished from G1 by some biochemical parameters including G0- and G1-specific intracellular proteins4,5. SV40- or polyoma virus-transformed cells cannot enter G0 to become quiescent6–9. Serum induces the growth of BALB/c 3T3 cells in tissue culture. It sustains the growth of exponentially replicating populations, and causes density-inhibited cells to leave G0 and replicate10–12. Serum contains several sets of hormonal growth factors which have recently been defined2,13,14. One of these hormones, the platelet-derived growth factor (PDGF), is released into serum during the clotting process; PDGF is absent in platelet-poor plasma, the liquid portion of unclotted blood15–19. It promotes the growth of G0-arrested cells2,16 by stimulating cells to become ‘competent’ to enter the S phase2; plasma allows these competent cells to progress through G0/G1, synthesise DNA2,20 and divide13. We now show that PDGF has a second function. It prevents replicating cells from entering G0.
Science and sociology butt heads in tomography experiment in Sacred Mountains

After a lengthy battle against opposition by specific interest groups, researchers with the Jemez Tomography Experiment (JTEX) investigated the crustal structure beneath a large, continental silicic magmatic system in the Jemez Mountains of New Mexico (Figure 1) in 1995. The seismic component involved both active and passive sources as well as a modest effort to interpret existing magnetotelluric data acquired during geothermal exploration of Valles caldera. While the data are still being processed and interpreted, early results indicate that magma is present in the middle crust and that an additional negative velocity anomaly exists at the base of the crust. Additionally, the southeastern part of the caldera is at least a kilometer deeper than the northwestern part.
Electrostatic storage tube

ALL COMPUTING machines and information-processing devices require some type of storage. Analogue computers have information storage scattered through the machine as part of the computing elements. For example, an electronic analogue computer might have a simple resistance-inductance-capacitance computing circuit whose basic storage would be twofold. The instructions for the type of computation would be stored in the interconnections of the resistance, inductance, and capacitance components. The initial conditions and partial and final results would be stored as current and voltage in the components of the computer.