cssi/SciSciGPT-SciSciNet huggingface dataset:
Spin-resolved density of states at the surface of NiMnSb

Spin-resolved photoemission measurements from polycrystalline NiMnSb films reveal spin-resolved density of states which are in qualitative agreement with local spin density functional band structure calculations [Phys. Rev. B 51, 10 436 (1995)]. The polarization of electrons close to the Fermi level is however found to be at most 40%, in contrast to the predicted half-metallic behavior. This discrepancy is attributed to lower remnant magnetization of the surface region and/or the presence of other phases.
Wave-energy density and wave-momentum density of each species of a collisionless plasma

LBL-1 0414 C • Preprint published in Physical Review A LiBRARY ANL WAVE-ENERGY DENSITY AND WAVE-MOMENTUM DENSITY OF EACH SPECIES OF A COLLISIONLESS PLASMA John R. Cary and Allan N. Kaufman November 1979 y TWO-WEEK LOAN is a Library Circulating Copy which may be borrowed a personal two weeks. copyft Divisiony Ext 6782. Prepared for the U.S. Department of Energy under Contract W-7405-ENG-48
Finite Element Analysis of Residual Stresses in High-Speed Dry Cutting of Biodegradable Magnesium-Calcium Alloy

Magnesium-Calcium (Mg-Ca) alloys have become attractive biodegradable orthopedic implant biomaterials recently. Residual stresses are proven to be very influential on degradation rate of these alloys in human anatomy. Due to time and cost inhibitive reasons, development of finite element models to predict residual stress profiles under various cutting regimes is highly desirable. In this context, a finite element model of orthogonal cutting without explicit chip formation is developed by adopting plowing depth approach in order to predict process induced residual stresses in high speed dry cutting of Mg-Ca0.8 (wt %) using diamond tools. Mechanical properties of Mg-Ca0.8 alloy at high strain rates and large strains are determined using split-Hopkinson pressure bar test. Internal state variable (ISV) plasticity model is implemented to model the material behavior under cutting regimes. The residual stress evolution process and effects of plowing speed and plowing depth on residual stress profiles are studied. Residual stress measurements are performed utilizing X-ray diffraction technique for validation purposes.Copyright © 2012 by ASME
RELATIONSHIPS AMONG REPRODUCTION, GROWTH RATES, AND PROTEIN HETEROZYGOSITY IN PONDEROSA PINE

This report summarizes a 6-yr study of male and female cone production in a population of 216 ponderosa pines whose ages, diameters, and genotypes at 7 protein polymorphisms are known. There are different schedules of male and female reproduction. The majority of cones are produced by the same few trees each year. There is a tradeoff between growth rate and female cone production but not pollen production. Differential female (but not male) cone production is associated with protein genotype. The variance of female reproductive effort declines with increasing protein heterozygosity. LONG-LIVED, iteroparous species tend to have complex life histories and variable schedules of reproduction. Reproduction is often highly varzable from year to year, and years of abundant seed production, called "mast" years, are characteristic of many forest trees. Masting seems to be advantageous in reducing seed destmction by various animals (Harper, 1977; Silvertown, 1980). While such yearly variation in reproduction is a recognized characteristic of long-lived plants, it is seldom known what proportion of a population reproduces and whether specific individuals are consistently low or high reproducers year after year. Relative allocation to pollen and seed production are also variable in long-lived species. Monoecious species are particularly interesting in this respect because they can be very flexible in their timing and allocation of energy to male and female reproduction. This flexibility is just beginning to be explored in an ecological context (Charnov, 1982; Willson, 1983; Willson and Burley, 1983). The role played by genetic variation in all this complexity is poorly known and only beginning to be documented (Dingle and Hegmann, 1982). Here we describe the associations between male and female cone production, growth rate, and protein genotypes. The data were collected
Structural evidence for a germline-encoded T cell receptor-major histocompatibility complex interaction 'codon'

All complexes of T cell receptors (TCRs) bound to peptide–major histocompatibility complex (pMHC) molecules assume a stereotyped binding 'polarity', despite wide variations in TCR-pMHC docking angles. However, existing TCR-pMHC crystal structures have failed to show broadly conserved pairwise interaction motifs. Here we determined the crystal structures of two TCRs encoded by the variable β-chain 8.2 (Vβ8.2), each bound to the MHC class II molecule I-Au, and did energetic mapping of Vα and Vβ contacts with I-Au. Together with two previously solved structures of Vβ8.2-containing TCR-MHC complexes, we found four TCR–I-A complexes with structurally superimposable interactions between the Vβ loops and the I-A α-helix. This examination of a narrow 'slice' of the TCR-MHC repertoire demonstrates what is probably one of many germline-derived TCR-MHC interaction 'codons'.
Detection and partial purification of two lipases fromCandida rugosa

Two distinct lipases produced byCanadida rugosa were identified and separated by a high resolution anion-exchange column (Mono Q) after an ethanol extraction of the crude lipase. From this Mono Q column, lipase I eluted at 0.05 M NaCl whereas lipase II eluted at 0.15 M NaCl. The less anionic nature of lipase I was also confirmed by native polyacrylamide gel electrophoresis as well as isoelectrophoresis. Both proteins have an apparent molecular weight of 58,000 by SDS-PAGE. The isoelectric points of lipase I and II are 5.6 and 5.8 respectively.
Effect of experience on in-flight orientation to host-associated cues in the generalist parasitoid Lysiphlebus testaceipes

The effect of experience on the responsiveness of the aphidiid parasitoid Lysiphlebus testaceipes (Cresson) (Hymenoptera: Aphidiidae) to host-associated cues was investigated using a wind-tunnel bioassay. Naive females were able to discriminate between uninfested wheat (Triticum aestivum L.) and wheat infested with Schizaphis graminum (Rondani) (Homoptera: Aphididae), but oviposition experience significantly increased the parasitoid's propensity to respond to aphid-infested plants with upwind, targeted flight. The behavioural change associated with such experience was acquired rapidly (within five minutes) and persisted for at least 24 h. The parasitoid could be successfully conditioned to associate a novel odour with the presence of hosts, suggesting that the increase in response to aphid-infested plants which occurs as a result of experience is probably due to associative learning of olfactory cues from the plant-aphid complex.
Optimum Profile Modifications for the Minimization of Static Transmission Errors of Spur Gears

A procedure for computing static transmission errors and tooth load sharing was developed for low and high contact ratio internal and external spur gears. A suitable optimization algorithm was used to minimize any combination of the harmonics of gear mesh frequency components of the static transmission error. Different combinations of tip and root relief may be used to achieve optimization. These include varying the starting point of relief and varying the magnitude of relief, and selecting the gear and/or the pinion teeth to be tip and/or root-relieved. Also, there exists an option for using either linear or parabolic relief. In addition to the presentation of optimal profile modifications, the effects of off-design loads, nonoptimum modifications, and random spacing errors are presented.
Protoplast induction in Chlorella pyrenoidosa

Abstract Chlorella pyrenoidosa (UTEX 1230) cells in late log phase of growth were induced to form viable protoplasts by enzymatic digestion only when incubated in 2-deoxy-d-glucose (2DG) for 24 h. The combination of hemicellulase (4% w/v), Cellulysin (4% w/v), and glucuronidase (5% v/v) with 0.8 M mannitol and 8 mM CaCl2 in modified Bristol's solution, was most effective for obtaining viable protoplasts as determined by light and electron microscopy, and vital staining with primuline (0.01% w/v). Resistance of cell walls to extensive extraction (acetolysis), and infrared analysis indicated that sporopollenin is a component of the cell wall. Transmission electron miscroscopy of acetolysed cell walls also allowed visualization of the laminate nature of the wall. This is the first report of successful induction of protoplasts from algae which contain sporopollenin in their cell walls.
Ancestral traits, parental populations, and hybrids

The distance traveled over the centuries by any human population is a rocky road; the fusion of the paths of two meandering populations often leads to an even rougher one. Tracing such a wayward child of history back to its long-lost parents presents complex problems for the physical anthropologist. For those parents may share unequally in their legacy to their offspring at the start of the journey. Many genes may disappear into the gutters of genetic drift; some byways may stop at the barricades of selection; fresh migrants may join by side roads to swell the stream; and inbreeding may narrow the roadbed. Searching for the genes that the hybrid population holds in common with alleged parents provides one clue to the relative role of the ancestors. Comparison of measurements of the living hybrid with the nearest known relatives of the presumed parents yields another clue. Resuscitation of ancestors from their bones and teeth supplies yet another link. Distinctive features of such skeletal remains are most valuable where their inheritance is understood. Bones may yield another clue from substances left within them of known genetic control. And finally all the evidence of history, every glimpse caught of the population along the route, gives knowledge of the contribution of the forebears to the living people. The ideal estimate will utilize a wide variety of information about the known groups.
Solar flare precursors

Recent progress in the study of flare precursors and onset is reviewed. New theoretical results on filament formation and erution are presented, including especially the dynamical effects of magnetic fields. Ample evidence is found that energetic processes are already at work in the onset phase, a few minutes before the rapid rise of the hard-radiation impulse. In particular, the prevalence of soft and hard X-ray preheating (to less than 100 million K) is detailed, along with a connection to the launch of coronal mass ejections. A possible interpretation of the empirical time profiles near onset is that 'preheating' signifies that the flare has slowly started, and the transition to the impulsive stage then represents a change of phase in the flare-instability process. Finally, the problem of the interpretation of microwave preflare data is delineated.
Load balancing for multi-projector rendering systems

Multi-projector systems are increasingly being used to provide large-scale and high-resolution displays for next-generation interactive 3D graphics applications, including large-scale data visualization, immersive virtual environments, and collaborative design. These systems must include a very high-performance and scalable 3D rendering subsystem in order to generate high-resolution images at real-time frame rates. This paper describes a sort-first parallel rendering system for a scalable display wall system built with a network of PCs, graphics accelerators, and portable projectors. The main challenge is to develop scalable algorithms to partition and assign rendering tasks effectively under the performance and functionality constraints of system area networks, PCs, and commodity 3-D graphics accelerators. We have developed three coarse-grained partitioning algorithms, incorporated them into a working prototype system, and run initial experiments aimed at evaluating algorithmic trade-offs and performance bottlenecks in such a system. Results of our experiments indicate that the coarse-grained characteristics of the sort-first architecture are well suited for constructing a parallel rendering system running on a PC cluster.
Thyrotropin can increase the steady state level of a messenger ribonucleic acid species (glyceraldehyde-3-phosphate dehydrogenase) in thyroid cells by decreasing its rate of disappearance.

A cDNA clone (G18) was selected from an FRTL5 rat thyroid cell cDNA library by a differential screening procedure designed to identify TSH-responsive genes in thyroid cells. Nucleotide sequence analysis indicated that G18 was rat a-glyceraldehyde-3-phosphate dehydrogenase (GAPD). On Northern blot analysis, TSH increased GAPD mRNA levels in FRTL5 cells, reaching a maximum (4- to 10-fold above basal in different experiments) after approximately 24 h of TSH stimulation. Run-on transcription assays with nuclei prepared from quiescent and TSH-stimulated FRTL5 cells indicated that the action of TSH to increase GAPD mRNA levels was not associated with an increase in the transcriptional activity of this gene. Examination of the rate of disappearance of GAPD mRNA levels after inhibition of mRNA transcription by actinomycin-D revealed that TSH stimulation of FRTL5 cells stabilized the GAPD mRNA (t1/2 extended from 9 to 56 h). In summary, the present data provide the first demonstration that TSH can increase the lev...
A case of protracted coxsackie virus meningoencephalitis in a marginally immunodeficient child treated successfully with intravenous immunoglobulin

A child with acute lymphocytic leukemia who was in clinical remission and developed coxsackie B4 meningoencephalitis is presented. Despite minimal evidence of immunodeficiency, the patient had progression of neurologic disease clinically, electroencephalographically and on laboratory evaluation of spinal fluid. A dramatic response to the use of intravenous immunoglobulins is reported and its rationale explained.
SU‐FF‐T‐616: Influence of Respiratory Motion On Helical Tomotherapy Treatment Planning for Chest Wall Irradiation

Purpose: To investigate the influence of respiratory motion on helical tomotherapy treatment plans for chest wall irradiation. Methods and Materials: Helical tomotherapy plans were generated on 3DCT and 4DCT data for post‐mastectomy radiation therapy patients. Plans were generated on the 4DCT data for 0% phase (full inspiration), 50% phase (full exhalation), and the minimum and maximum intensity projection (MIP) data. Since TomoTherapy dose delivery incorporates a temporal component, the result of respiratory motion is dependent on the specific phase interplay of the breathing cycle and the TomoTherapy rotation. As an approximation, we performed treatment planning on the extrema phases (i.e., full inhale and full exhale) of the breathing cycle. Though this does not represent true respiration, it does represent the worst case effect of respiration as a displacement of the anatomy relative to the treatment beam for the entire delivery. Plans were compared based on dose volume histograms (DVHs) for the planning target volume (PTV) and organs at risk (OARs), dose homogeneity indices (DHIs), percentage of PTV receiving the prescription dose, minimum dose received by 90% of PTV, and maximum (Dmax) and minimum (Dmin) doses in the PTV. Results: DVHs show insignificant differences for OAR (lungs,heart) for the four planning geometries. The tumor control probability (TCP) is 100% for all cases, and DHI varies from 0.125 to 0.165 (hot spots 110–113%, cold spots 96–98%). Conclusions: We conclude that there is little dosimetric and radiobiological difference among these results and that the respiratory motion does appear to have a clinically significant effect on the treatment plans. Conflict of Interest: This work was supported in part by a research agreement with TomoTherapy, Inc.
Coronary angioscopy before and after stent deployment

ABSTRACT Coronary angioscopy was used in attempt to visualize the internal architecture of cardiac vessels before and afterdeployment of Palmaz-Schatz stents in 50 patients. The vessel was successfully visualized in 48 (96%) of thesepatients. In 24 patients, angioscopy was pertormed both after preliminary balloon angioplasty and then again after stent deployment. In all 24 patients the diameter of the lumen appeared larger after stent deployment ascompared to after balloon angioplasty. In 16 of these 24 patients a dissection was documented by angioscopy after balloon angioplasty. The dissection was absent after stent deployment in all 16 patients. In seven patients, thrombus that was not apparent by angiography was visualized by angioscopy. Moreover, in four patients,thrombus that was suggested by angiography could not be confirmed by angioscopy. Other significantobservations by angioscopy included: (1) the visualization of atherosclerotic plaque bulging into the vessellumen at the stent articulation site in nine patients; (2) the visualization of significant stenoses upstream or
Fracture interpretation using electronic presentation: a comparison.

The purposes of this study were to determine whether (1) fractures are interpreted differently after digitization and electronic presentation; (2) there are differences in accuracy between screen radiographs and electronic presentation; (3) differences in interpretation are a function of monitor resolution; and (4) differences in interpretation between radiographs and electronic images relate to radiological subspecialty. Forty cases with fractures of varying degrees of subtlety and 35 cases without fractures were interpreted. Radiographs were digitized with 2 different systems and displayed on 3 monitors of different spatial resolution. Four radiologists, with varying experience, were asked to decide whether fractures were present, absent, or they were uncertain. Accuracy of interpretation increased with improved electronic image presentation and monitor resolution. The sensitivity, specificity, and accuracy of fracture detection on System A were 63%, 98%, and 78%, respectively. The results were 72%, 98%, and 84% with System B. System C results were 81%, 97%, and 88% with Lumiscan 75, and 82%, 96%, and 88% with Lumiscan 150. Sensitivity, specificity, and accuracy results of the original radiograph interpretation were 89%, 95%, and 92%. Results were significantly different for System A. No significant differences were found for the other systems compared with film radiographs. System A did not have adequate monitors for interpretation of subtle fractures. Systems B and C were capable of displaying even subtle fractures. Our initial results indicate that interpretation with high-quality 1K×1K monitors is substantially similar to radiograph interpretation.
Dye-Binding Capacity of Milk Proteins for Amido Black 10B and Orange G

Summary Orange G dye shows more stoichiometry in its reaction with milk proteins than does Amido Black, although the latter gives a higher dye-binding capacity (DBC). DBC values for the major milk proteins have been determined at three levels of protein and for both dyes. In general, there is a parallel trend in the amount of each dye bound, showing that the same protein groups are involved. DBC values for Amido Black decrease more rapidly with increasing protein :dye ratios than do the corresponding values for Orange G. Absorbancy indices for the purest dyes available were determined: K = 46.9 for Orange G at 475 mµ, and K = 81.5 for Amido Black at 615 mµ. These values are for concentrations expressed as mg/ml in a 1-cm cuvette. Since there is so much variability in dye assays, it is recommended that absorbancy index be used to standardize the dye reagent.
Temporomandibular disorders and chronic pain: Disease or illness?

Temporomandibular disorders (TMD) are examined from a biopsychosocial or illness perspective. Data are reviewed in accordance with the concept that TMD is a chronic pain condition that shares many features with other common chronic pain conditions. TMD is placed within the same biopsychosocial model currently used to study and manage all common chronic pain conditions. The concept of chronic pain dysfunction, which has emerged as a critical consideration for chronic pain research and management, is also reviewed. Most chronic pain patients seem to bear their condition adequately and thus maintain adaptive levels of psychosocial function. By contrast, a psychosocially dysfunctional segment of the chronic pain population appears unable to cope as well and demonstrate higher rates of depression, somatization, and health care use, even though persons in this segment are not different from their functional peers on the basis of observable organic pathology. Finally, data are reviewed from longitudinal, epidemiologic, and experimental intervention studies that substantiate these two perspectives.
The effects in vivo of hypoxia on brain injury.

Abstract To separately analyze the hypoxic component of hypoxic-ischemic encephalopathy, rats were prepared such that their p a 0 2 was maintained at 20 mmHg while maintaining systemic arterial pressures. During the 20-min experiment, brain oxygen concentration and extracellular amino acid concentrations were monitored. At sacrifice, the brains were studied for morphologic evidence of injury by immunocytochemical staining for the non-constituitive stress protein HSP-72 or neuronal death by acid fuchsin staining. Oxygenated rats subjected to global ischemia were prepared for comparison. In these experiments, hypoxia resulted in no increase in extracellular glutamate concentration, and no morphologic injury was detected. Thus, hypoxia without ischemia is well tolerated by brain.
The effects of ethnicity on career paths of advanced/specialized law enforcement officers

The effects of ethnicity on the career paths of advanced and specialized law enformcement officers are examined. Analyses focus on two measures of possible perceived or actual employment discrimination by ethnicity. Ethnicity is found to be a minor indicator of rank compared to experience and education. A differential distribution of rank by ethnicity was found in some departments and in the total sample in some rank categories. Lack of ethnic diversity became increasingly disproportional as rank rose. Analysis of length of assignment shows all minority groups and females proceeding through their career paths more quickly than white males. Findings are presented with policy implications.
The Effect Of Short Term, Light Resistive Exercise On Well Elders

The effect of light resistive exercise on thigh muscle strength and endurance was studied in well elderly subjects. Strength and endurance measurements were taken before and after a six week exercise regime using the Biodex isokinetic dynamometer. The results demonstrated no significant difference between the preexercise and postexercise measurements. It was concluded that the resistance used in this study was too low to effect muscle strength or endurance. Clinicians should be cognizant that exercise without the appropriate amount of resistance may not have an effect on well elderly individuals.
Targeting FoxO1 with AS1842856 Suppresses Adipogenesis

Hyperplasia (i.e., increased adipogenesis) contributes to excess adiposity, the hallmark of obesity that can trigger metabolic complications. As FoxO1 has been implicated in adipogenic regulation, we investigated the kinetics of FoxO1 activation during adipocyte differentiation, and tested the effects of FoxO1 antagonist (AS1842856) on adipogenesis. We found for the first time that the kinetics of FoxO1 activation follows a series of sigmoid curves, and reveals the phases relevant to clonal expansion, cell cycle arrest, and the regulation of PPARγ, adiponectin, and mitochondrial proteins (complexes I and III). In addition, multiple activation-inactivation transitions exist in the stage of terminal differentiation. Importantly, persistent inhibition of FoxO1 with AS1842856 almost completely suppressed adipocyte differentiation, while selective inhibition in specific stages had differential effects on adipogenesis. Our data present a new view of FoxO1 in adipogenic regulation, and suggest AS1842856 can be an anti-obesity agent that warrants further investigation.
EXPERIMENTAL HIGH JEJUNOSTOMY IN THE DOG, WITH BLOOD CHEMICAL STUDIES

1. The effect of high jejunostomy upon the life and chemical changes of the blood of dogs is here reported. 2. Sodium chloride solution administered in sufficient quantity after high jejunostomy prolongs the life of dogs. 3. Such experimental findings as these warrant a careful cinical study of the effects of high jejunostomy so frequently used in the treatment of acute intestinal obstruction.
The activity of Clostridium histolyticum proteinase on synthetic substrates.

Abstract An extracellular proteinase preparation of Cl. histolyticum has been prepared by precipitation of cell-free filtrates with methanol. This preparation was essentially free from collagenase activity, lethal toxin, and intracellular peptidase activity. When the cell-free filtrates were adjusted to pH values from 4.5 to 8.5 and then precipitated with methanol at final concentrations of 40–67% the products obtained had essentially the same activity toward synthetic substrates. The proteinase preparation hydrolyzed l -arginine methyl ester, α-benzoyl- l -argininamide, the ethyl, benzyl, and isopropyl esters of α-benzoylarginine, and very slowly, l -lysine methyl ester. The pH optimum for the hydrolysis of l -arginine methyl ester in phosphate buffer was about 7.2. The proteinase could be activated by cysteine, glutathione, and potassium cyanide. Citrate, borate, veronal, and tris(hydroxymethyl)-aminomethane buffers partially inhibited the proteinase action on arginine methyl ester. A method has been described for the use of l -arginine methyl ester as a substrate for following the purification and characterization of the proteinase. The activity of the proteinase toward l -arginine methyl ester can be increased fourfold by reprecipitation in the presence of zinc acetate with low concentrations of ethanol.
Brianthein Z, A new polyfunctional diterpene From the Gorgonian

Abstract A novel diterpene and possible chemotaxonomic marker has been isolated from the gorgonian Briareum polyanthes . The gross structure has been determined and relative configuration is proposed.
Public Perceptions of Privatization in Ethiopia: A Case for Public Good or Private Gain?

Abstract Ethiopia is one of the many countries in sub-Saharan Africa attempting to privatize various state-owned enterprises since 1994. This study examined public perceptions about Ethiopia's privatization policy and procedures. Results support the concerns over the public's inability to know about, be involved in and comment upon public policies affecting Ethiopia's future. Findings also support the literature that a privatization policy is effective only when institutional and technical capacities for proper implementation are in place. Further, findings raise questions about the efficacy of privatization in a national context where interests may be misrepresented.
Oligomers of the prion protein fragment 106-126 are likely assembled from β-hairpins in solution, and methionine oxidation inhibits assembly without altering the peptide's monomeric conformation

A portion of the prion protein, PrP106-126, is highly conserved among various species and is thought to be one of the key domains involving amyloid formation of the protein. We used ion mobility spectrometry-mass spectrometry (IMS-MS) in conjunction with replica exchange molecular dynamics (REMD) to examine the monomeric and oligomeric structures of normal PrP106-126 and two nonaggregating forms of the peptide, an oxidized form in which both methionine residues are oxidized to methionine sulfoxide and a control peptide consisting of the same amino acids as PrP106-126 in a scrambled sequence. Our ion mobility and simulation data indicate the presence of a population of beta-hairpin monomers for the normal and oxidized peptides. This is supported by our CD data indicating that a monomer solution of the normal peptide contains approximately 46% beta-sheet and approximately 23% beta-turn content, in excellent agreement with our REMD simulations. Oligomerization was seen by IMS-MS for the normal peptide only, not the oxidized peptide or the control sequence. Both our IMS-MS and CD data suggest that this oligomerization results from the association of ordered beta-hairpin monomers rather than disordered monomers. Structural analysis shows that the normal and oxidized peptides have similar secondary and tertiary structural properties, suggesting that the inhibition of aggregation caused by methionine oxidation stems from mediating interpeptide interactions rather than by altering the peptide's monomeric conformation. In contrast, an increase in alpha-helical and random coil structural components relative to the normal peptide might be responsible for the lack of observed aggregation of the control peptide.
Prairie rattlesnake seasonal migrations: episodes of movement, vernal foraging and sex differences

Abstract Functional study of animal migration in nature requires both description and empirical analysis of component episodes of movement dedicated to the potential solution of problems in survival. Good study systems are those exhibiting larger patterns of migration that can be partitioned empirically into functionally analysable, component episodes. This facilitates analysis of alternative explanations both for larger cycles of migration and the component episodes that comprise them. Free-ranging prairie rattlesnakes, Crotalus viridis viridis, are good subjects in this respect. Results of a long-term field study of radiotagged individuals indicate that while both males and females search for small mammal prey in the first half of the brief, 35-month summer in Wyoming, males but not females search for mates in the second half of the season. Females continue to forage for the duration of the season. Accordingly, males must search for and locate two stations in time and space (food and mates) each season, while females need search only for one (food). Given this difference, males and females exhibit predicted differences in key patterns of seasonal activity. Males exhibit significantly greater spatial searching efficiency during the vernal foraging episode than females, allowing males to concentrate foraging activities into the first half of the season, so that the second can be largely dedicated to a search for females. The mating system of prairie rattlesnakes in Wyoming is best described as prolonged mate searching polygyny.
Urban Industrial Reform in China: Problems and Prospects

This article places urban industrial reform in China in its broad historical context. The reform initiatives to date are a direct reaction to shortcomings of planning. While decentralization and increased reliance on markets and short-range managerial decisionmaking are more commonly noted in discussions about change in China, interpretation of current reforms should emphasize centralization of certain long-range aspects of the planning process, such as investment and basic price structure. Events prior to and following Tiananmen Square become more meaningful within this broader perspective.
The Effects of Age at Kindergarten Entry on the Reading Proficiency of African American and European American Students

European American students are more likely delayed entrance in kindergarten than African American students. This study examined whether age at kindergarten entry influences the reading proficiency skills of African American and European American students at the start of kindergarten, at the end of first grade, and at the end of third grade. Using a sample of 1,320 African Americans and 4,399 European American public school students from the Early Childhood Longitudinal -Study-K-5, the study found that age at kindergarten entrance had a significant effect on the reading proficiency at the start of kindergarten and by the end of third grade. In addition, the study found that when entering kindergarten when age eligible, the reading proficiency skills of African American and European American students were not significantly different and neither was the reading proficiency growth between kindergarten and third grade.
Angiotensin-Converting Enzyme and Lipoprotein(a) as Risk Factors for Myocardial Infarction

In this issue Badenhop et al1 present a study of genetic markers in schoolchildren and death from coronary artery disease or myocardial infarction or a history of coronary artery bypass surgery or angioplasty in their grandparents. The study shows a correlation between these end points and both an angiotensin-converting enzyme (ACE) genotype and the plasma concentration of lipoprotein(a) [Lp(a)]. These observations remind us that we do not fully understand the risk factors governing coronary artery disease. Over many years, a wealth of studies have identified smoking, hypertension, sex, increased low-density lipoprotein (LDL) cholesterol, diabetes mellitus, and a sedentary lifestyle as having a significant impact on the incidence of arteriosclerosis and myocardial infarction or stroke. Yet data from the Framingham Study show that the probability of developing one of the manifestations of coronary artery disease within 10 years is 6% for a 50-year-old man without any of the known risk factors; for a 60-year-old man in the same condition, the probability is 9%.2 It is not surprising, then, that the identification of other risk factors for arteriosclerosis and its consequences —especially those factors for which a positive linkage exists between a genetic locus and disease—remains the focus of considerable research activity. Of particular interest in the context of the report by Badenhop et al1 are the plasma concentrations of angiotensin II and Lp(a). Angiotensin II is a potent vasoconstrictor, cardiac inotropic agent, and smooth muscle cell growth factor. Elevated levels of angiotensin II have been recognized for some time to correlate with hypertension, and they appear to be associated with an increased risk of myocardial infarction.3 The plasma and tissue concentrations of angiotensin II are determined by the renin-angiotensin system. The enzyme renin cleaves its substrate angiotensinogen to release an inactive peptide, angiotensin I. A second enzyme, …
Comparison of the aerodynamic size distribution of chain-like aggregates measured with a cascade impactor and a spiral centrifuge.

Several authors have suggested that chain-like aggregates fragment in the jets of cascade impactors and that the impactor consequently underestimates the median aerodynamic diameter and overestimates the geometric standard deviation (GSD). The aerodynamic size distribution of (Pu0.14U0.86)O2.2 aggregates were measured simultaneously with two Mercer cascade impactors and a LAPS spiral centrifuge to investigate this problem. Although the median aerodynamic diameters were generally in good agreement, the impactor consistently measured higher values for the GSD than did the spiral centrifuge. Based on experiments in which losses in the centrifuge inlet were measured, it was concluded that the centrifuge had measured the aerodynamic size distribution more accurately than the impactor. Interception of chain-like aggregates on the first few impactor stages may have been the primary reason for the disparity between the impactor and centrifuge measurements.
A constrained mixture model for arterial adaptations to a sustained step change in blood flow

A sustained change in blood flow results in an arterial adaptation that can be thought to consist of two general steps: an immediate vasoactive response that seeks to return the wall shear stress to its homeostatic value, and a long-term growth and remodeling process that seeks to restore the intramural stresses and, if needed, the wall shear stress toward their homeostatic values. Few papers present mathematical models of arterial growth and remodeling in general, and fewer yet address flow-induced changes. Of these, most prior models build upon the concept of “kinematic growth” proposed by Skalak in the early 1980s (Skalak R (1981) In: Proceedings of the IUTAM Symposium on finite elasticity. Martinus Nijhoff, The Hague, pp 347–355). Such approaches address important consequences of growth and remodeling, but not the fundamental means by which such changes occur. In this paper, therefore, we present a new approach for mathematically modeling arterial adaptations and, in particular, flow-induced alterations. The model is motivated by observations reported in the literature and is based on a locally homogenized, constrained mixture theory. Specifically, we develop a 3-D constitutive relation for stress in terms of the responses of the three primary load-bearing constituents and their time-varying mass fractions, with the latter accounting for the kinetics of the turnover of cells and extracellular matrix in changing, stressed configurations. Of particular importance is the concept that the natural configurations of the individual constituents can evolve separately and that this leads to changes in the overall material properties and empirically inferred residual stress field of the vessel. Potential applications are discussed, but there is a pressing need for new, theoretically motivated data to allow the prescription of specific functional forms of the requisite constitutive relations and the values of the associated material parameters.
Critical roles for nitric oxide and ERK in the completion of prosurvival autophagy in 4OHTAM-treated estrogen receptor-positive breast cancer cells

Autophagy is a mechanism of tamoxifen (TAM) resistance in ER-positive (ER+) breast cancer cells. In this study, we showed in ER+ MCF7 cells that 4-hydroxytamoxifen (4OHTAM) induced cellular nitric oxide (NO) that negatively regulates cellular superoxide (O2−) and cytotoxicity. 4OHTAM stimulated LC3 lipidation and formation of monodansylcadaverine (MDC)-labeled autophagic vesicles dependent on O2−. Depletion of NO increased O2− and LC3 lipidation, yet reduced formation of MDC-labeled autophagic vesicles. Instead, NO-depleted cells formed remarkably large vacuoles with rims decorated by LC3. The vacuoles were not labeled by MDC or the acidic lysosome-specific fluorescence dye acridine orange (AO). The vacuoles were increased by the late stage autophagy inhibitor chloroquine, which also increased LC3 lipidation. These results suggest NO is required for proper autophagic vesicle formation or maturation at a step after LC3 lipidation. In addition, 4OHTAM induced O2−-dependent activation of ERK, inhibition of which destabilized lysosomes/autolysosomes upon 4OHTAM treatment and together with depletion of NO led to necrotic cell death. These results suggest an essential role for endogenous NO and ERK activation in the completion of pro-survival autophagy.
Volunteering in a Short-Term English Immersion Program for Spanish-Speaking Adults

This article describes English immersion programs in Spain, where native English speakers volunteer as conversation partners and informal tutors for native Spanish speakers. These Spaniards are at ...
A security model for military message systems

Military systems that process classified information must operate in a secure manner; i.e., they must adequately protect information against unauthorized disclosure, modification, and withholding. A goal of current research in computer security is to facilitate the construction of multilevel secure systems, systems that protect information of different classificationsfrom users with different clearances. Security models are used to definethe concept of security embodied by a computer system. A single model, called the Bell and LaPadula model, has dominated recent efforts to build secure systems but has deficiencies. We are developing a new approach to defining security models based on the idea that a security model should be derived from a specificapplication. To evaluate our approach, we have formulated a security model for a family of military message systems. This paper introduces the message system application, describes the problems of using the Bell-LaPadula model in real applications, and presents our security model both informally and formally. Significantaspects of the security model are its definition of multi-level objects and its inclusion of application-dependent security assertions. Prototypes based on this model are being developed.
POSAML: A visual modeling language for middleware provisioning

Next generation distributed applications are often hosted on heterogeneous platforms including different kinds of middleware. Due to the applications' growing functional complexity and their multiple quality of service (QoS) requirements, system developers are increasingly facing a substantial number of middleware provisioning challenges, which include configuring, optimizing and validating the middleware platforms for QoS properties. Traditional techniques for middleware provisioning tend to use non-intuitive, low-level and technology-specific approaches, which are tedious, error prone, and non-reusable across different technologies. Quite often the middleware provisioning activities are carried out by different actors without much interaction among them, which results in an iterative trial-and-error process to provisioning. Higher level abstractions, particularly those that use visual models, are effective in addressing these challenges. This paper describes the design of a visual modeling language called POSAML (pattern-oriented software architecture modeling language) and associated tools that provide an intuitive, higher level and unified framework for provisioning middleware platforms. POSAML provides visual modeling capabilities for middleware-independent configurations and optimizations while enabling automated middleware-specific validation of system QoS properties.
A Hierarchical Model for Firewall Policy Extraction

Firewalls are one of the most widely used mechanisms against security threats in distributed andnetwork systems.However, principled methodologies for firewall extraction policies have been scarcely investigated so far.We introduce a new model for translating low level firewall rules into higher abstraction level rules which allow for the inference of firewall policies. In order to do so, we introduced a new methodology based on rules' decorrelation algorithms that compute hierarchical firewall policies from lower level firewall rules. Further, we define a new effective model for the explicit extraction of blacklisted and whitelisted hosts and networks.
Improving the mean field approximation via the use of mixture distributions

Mean field methods provide computationally efficient approximations to posterior probability distributions for graphical models. Simple mean field methods make a completely factorized approximation to the posterior, which is unlikely to be accurate when the posterior is multimodal. Indeed, if the posterior is multi-modal, only one of the modes can be captured. To improve the mean field approximation in such cases, we employ mixture models as posterior approximations, where each mixture component is a factorized distribution. We describe efficient methods for optimizing the Parameters in these models.
A Numerical Study of Worker Exposure to a Gaseous Contaminant: Variations on Body Shape and Scalar Transport Model

Abstract Three-dimensional computational fluid dynamics simulations are used to investigate the distribution and level of contaminant concentrations in the true breathing zone (at the nose and mouth) when toxic airborne contaminants are released within an arm's length in front of the worker who has his back to the airflow. The effects of different body shapes on fluid flow and concentration patterns around the body in a wind tunnel were evaluated and clarified that a sharp body or a block may not be a good surrogate for the human form in consideration of occupational and environmental health studies. The comparison of the concentration field calculated with the Eulerian and Lagrangian methods revealed that the Eulerian method has a more diffusive nature than the Lagrangian method. The concentrations at different locations were also compared to determine the optimum sampling location. It was found that the concentration at the breathing zone may be significantly different from the one at the chest area. Th...
Legacies of historical land use on regional forest composition and structure in Wisconsin, USA (mid-1800s-1930s-2000s).

Historical land use can influence forest species composition and structure for centuries after direct use has ceased. In Wisconsin, USA, Euro-American settlement in the mid- to late 1800s was accompanied by widespread logging, agricultural conversion, and fire suppression. To determine the maximum magnitude of change in forest ecosystems at the height of the agricultural period and the degree of recovery since that time, we assessed changes in forest species composition and structure among the (1) mid-1800s, at the onset of Euro-American settlement; (2) 1930s, at the height of the agricultural period; and (3) 2000s, following forest regrowth. Data sources included the original U.S. Public Land Survey records (mid-1800s), the Wisconsin Land Economic Inventory (1930s), and U.S. Forest Service Forest Inventory and Analysis data (2000s). We derived maps of relative species dominance and tree diameters for the three dates and assessed change using spatial error models, nonmetric multidimensional scaling ordination, and Sorenson distance measures. Our results suggest that since the mid-1800s, hemlock and white pine have declined in absolute area from 22% to 1%, and the proportion of medium (25-,50 cm) and large-diameter (� 50 cm) trees of all species has decreased from 71% to 27% across the entire state. Early-successional aspen-birch is three times more common than in the mid-1800s (9% vs. 3%), and maple and other shade-tolerant species are increasing in southern areas formerly dominated by oak forests and savannas. Since the peak agricultural extent in the 1930s, species composition and tree size in northern forests have shown some recovery, while southern forests appear to be on a novel trajectory of change. There is evidence of regional homogenization, but the broad north-south environmental gradient in Wisconsin constrains overall species composition. Although the nature of the future forests will be determined in part by climate change and other exogenous variables, land use is likely to remain the driving factor.
What Are Nature's "natural" Ways Of Computing?

Today’s circuit elements are built out of physical materials, effectively characterized by macroscopic properties. To maintain the current rate ofprogress in miniaturization, we’ll eventually have to design compu ting elements based directly on microscopic physical effects. ln order best to exploit Nature’s potential for computation, we’ll have to ask a lot of questions before starting to give orders. What are Nature’s predispositions when it comes to computing? What types of computational processes are more naturally and directly supported by physics? What classes of computing tasks stand favored by Nature’s predispositions?