cssi/SciSciGPT-SciSciNet huggingface dataset:
Preliminary simulations in the use of fast neutrons to detect explosives hidden in cargo containers

Fast neutrons have the potential to be a powerful tool in explosives detection. Methods using elastically scattered neutrons would likely require fewer incident neutrons than those that depend on neutron absorption or inelastic scatter due to an increased interaction probability. This reduction would dramatically reduce dose rates and induced target radioactivity. In this study, a series of Monte Carlo (MCNP5) simulations were completed in order to investigate the use of elastically scattered neutrons in explosives detection, specifically explosives hidden inside standard-sized cargo containers. Fast neutrons were simulated with energies of 2.4 MeV, 14.1 MeV, or equivalent to that of a Cf-252 neutron source. Neutrons and gamma rays were tallied in seven idealized detectors arranged around a cargo container. Initial simulations characterized neutron scattering behavior in several different materials, including water, oil, steel, air, soil, and the explosive, RDX (C2H6N6O6). Further simulations dealt with a theoretical scenario in which a 1.87 m diameter solid sphere of RDX was placed inside a cargo container, shielded with water, oil, or steel, and probed using 14.1 MeV neutrons. Next, the presence of the ground was incorporated into this scenario. Several strategies were then used to determine possible flags that could determine the presence of the RDX. One strategy consisted of searching for changes in the backscattered neutron tallies due to changes in hydrogen concentration when RDX was present. A second strategy involved investigating the changes in scattered neutron flux at specific energies as a function of angle. Other potential flags were found by comparing the ratios of elastic and inelastic peaks in the neutron spectra at seven different angles. Preliminary analysis using this method showed several promising possibilities for detecting hidden explosives, such as an almost 20 fold decrease in the ratio of 9.8 MeV and 9.2 MeV neutrons at 60deg when RDX is present in an isolated oil-filled cargo container.
Overcoming the power wall: Connecting voltage domains in series

This paper analyzes an alternative for system-level power configuration of digital circuits. To overcome the "power wall" and enable low supply voltages for digital circuits, the voltage domains of microprocessors or other digital circuit elements are connected in series. This enhances overall system efficiency and performance by allowing both the digital circuits and the power delivery circuits to operate in their region of highest efficiency. Power consumption is dramatically reduced because multiple, independent voltage levels enable each processor to operate at its local minimum energy point. A comparative analysis of series and parallel voltage domains concludes that series voltage domains consume less power. Various voltage regulations schemes ranging from software, firmware, and hardware are presented. Some of the challenges and opportunities of series circuits are discussed.
Driving Performance, Adaptation, and Cognitive Workload Costs of Logo Panel Detection as Mediated by Driver Age

This study investigated the effect of on-road visual sign usage on young (≤22 years), middle-aged (23–64 years), and elderly (65+ years) driver performance, adaptive vehicle control behavior and mental workload. Eight simulated highway driving scenarios (the primary task) were presented along with an embedded secondary task of familiar business logo sign identification. Driver workload was manipulated by varying logo panel counts on service signs, including 6- and 9-panels. Results revealed comparable driving performance among the 9- and 6-logo conditions but significant differences in sign identification among age groups. Elderly drivers produced significantly lower sign identification accuracy than other age groups (at 54–57%). Both elderly and young drivers demonstrated significantly higher cognitive workload (reduced blink duration) in response to secondary task demands as compared to middle-aged drivers. The workload during sign identification led to significantly greater elderly adaptation behaviors (higher speed reductions) and performance degradations (greater lane deviations).
Review of Hendery (2012), Relative Clauses in Time and Space: A Case Study in the Methods of Diachronic Typology

Review of Hendery, Rachel. 2012. Relative Clauses in Time and Space: A case study in the methods of diachronic typology. (Typological Studies in Language.) Amsterdam/Philadelphia: John Benjamins. 281 pp. Hardbound: ISBN 978 90 272 0682 4 | €95.00 / $143.00 | e-Book: ISBN 978 90 272 7368 0 | €95.00 / $143.00
Total Synthesis of (-)-N-Methylwelwitindolinone B Isothiocyanate

The asymmetric synthesis of (−)-N-methylwelwitindolinone B isothiocyanate is reported. Critical challenges overcome through these studies include the stereoselective installation of the sterically congested C13 alkyl chloride and control of the wayward reactivity of the indole unit to standard oxidants. A Pt-catalyzed hydrosilylation helped stymie unwanted rearrangements facilitated by vinyl group participation during the chloride installation step, and a new FeII-catalyzed oxidation accomplished the problematic conversion of indole into 2-indolinone.
Population Based Paternity Rate and Partner Birth Outcomes among Utah Men with Inflammatory Bowel Disease

Population Based Paternity Rate and Partner Birth Outcomes Among Utah Men With Inflammatory Bowel Disease
Towards conformational fidelity of a quaternary HIV-1 epitope: computational design and directed evolution of a minimal V1V2 antigen

Structure-based approaches to antigen design utilize insights from antibody (Ab):antigen interactions and a refined understanding of protective Ab responses to engineer novel antigens presenting epitopes with conformations relevant to eliciting or discovering protective humoral responses. For human immunodeficiency virus-1 (HIV-1), one model of protection is provided by broadly neutralizing Abs (bnAbs) against epitopes present in the closed prefusion trimeric conformation of HIV-1 envelope glycoprotein, such as the variable loops 1-2 (V1V2) apex. Here, computational design and directed evolution yielded a novel V1V2 sequence variant with potential utility for inclusion in an immunogen for eliciting bnAbs, or as an epitope probe for their detection. The computational design goal was to engineer a minimal single-chain antigen with three copies of the V1V2 loops to support maintenance of closed prefusion V1V2 trimeric conformation and presentation of bnAb epitopes. Via directed evolution of this computationally designed single-chain antigen, we isolated a V1V2 sequence variant that in monomeric form exhibited preferential recognition by quaternary-preferring and conformation-dependent mAbs. Structural context and transferability of this phenotype to V1V2 sequences from all strains of HIV-1 tested suggest a conformation-stabilizing effect. This example demonstrates the potential utility of computational design and directed evolution-based protein engineering strategies to develop minimal, conformation-stabilized epitope-specific antigens.
Biophilic Cities: What Are They?

while we are already designing biophilic buildings and the immediate spaces around them, we must increasingly imagine biophilic cities and should support a new kind of biophilic urbanism. Exactly what is a biophilic city, what are its key features and qualities? Perhaps the simplest answer is that it is a city that puts nature first in its design, planning, and management; it recognizes the essential need for daily human contact with nature as well as the many environmental and economic values provided by nature and natural systems.
Looking Back: My Half Century as a Sociologist of Aging and Society

The 1960s do not seem to have been a propitious time to embark on a major project exploring social aspects of aging in the United States. In those days, when the baby boom cohorts were about to come of age, public attention was on young people rejecting traditional ways and in apparent revolt against those over 30 – not on aging, which was generally thought of primarily as growing old. Yet it was at that time that Matilda White Riley received a major grant from the Ford Foundation and the Russell Sage Foundation to pull together, evaluate, and analyze social science knowledge about the middle and later years. It was then, in the initial stages of the project, that I was invited to join in what turned out to be a lifelong career studying age and aging and a decades long association, collaboration, and friendship with Matilda Riley, one of the leading scholars in the field.
Thermal expansion behavior of δ-zirconium hydrides: Comparison of δ hydride powder and platelets

Abstract The thermal expansion coefficient of δ hydrides and the evolution of the d-spacing of δ hydride platelets in Zircaloy-4 during heat treatments were investigated by conducting synchrotron x-ray diffraction experiments. Identical experiments enabled a direct comparison of the d-spacing of δ zirconium hydride platelets with the d-spacing of the powder δ hydrides. By analyzing the experimental data of this study and the data available in the literature, the thermal expansion coefficient of pure δ hydrides was determined as 14.1 10−6 °C−1. A direct comparison of the d-spacings of δ hydride platelets in CWSR Zry-4 sheet and the powder δ hydride samples showed an evolution of temperature-dependent strains within the δ hydride precipitates in which the strain components normal to the platelet edges exceed that normal to the platelet face during cooling/precipitation but not during heating/dissolution above approx. 200 °C.
Cristóbal de Villalpando’s Adoration of the Magi: A Discussion of Artist Technique

As a key participant in the 1686 revitalization of the Guild of Painters and Gilders of Mexico City, Cristobal de Villalpando (c. 1649–1714) played a critical role in establishing a high standard of practice for painters in seventeenth-century Mexico and beyond.[1][1] Signed and dated at the
EarthCaching as a Possible Way to Raise Environmental Awareness

EarthCaching is a special form of geocaching. An EarthCache offers an earth science lesson by visiting a unique geological feature. The aim of the study was to find out if people who are involved in EarthCaching act more environmentally friendly than other persons, because the intensive study of physical geographic phenomena in nature could have positive effects on environmental awareness. The questionnaire from Schahn’s SEU 3 survey (1999) was used as the basis for the questionnaire the author used. The data was collected at the EarthCaching event in Goslar 2015. The answers were evaluated with the help of the program SPSS 24. First, the typical characteristics of EarthCachers are shown, which are then related to the results of Schahn’s questionnaire. The results suggest that there is a connection between environmental awareness and EarthCaching. In particular, the creation of EarthCaches can be conducive to environmental awareness. As the results show, this type of cache could be used even more in the future in the context of environmental education.
Nature beyond control: how expectations should inform decisions about human germline engineering.

In the ongoing discussion about the risks of reproductive human germline modification, scant attention has been paid to whether it could be reconciled with theories of psychological well-being. Even if safety and feasibility challenges could be overcome and germline engineering technology could be implemented in ways that avoid exacerbating social inequality, we would still have to question whether germline modification would promote circumstances that lead to better psychological experiences for parents, society, and the genetically edited person. This paper posits that germline engineering would produce expectations of being able to control the manifestation of an individual’s characteristics, which will inevitably be upset by our limited understanding of how genes interact with each other and with the environment. Drawing on self-discrepancy and relative deprivation theories, it is suggested that both editing and being edited could lead to unmet expectations and thus negative emotional states that would offset benefits of successful intended genetic changes.
Lagrangian particle method for compressible fluid dynamics

Abstract A new Lagrangian particle method for solving Euler equations for compressible inviscid fluid or gas flows is proposed. Similar to smoothed particle hydrodynamics (SPH), the method represents fluid cells with Lagrangian particles and is suitable for the simulation of complex free surface/multiphase flows. The main contributions of our method, which is different from SPH in all other aspects, are (a) significant improvement of approximation of differential operators based on a polynomial fit via weighted least squares approximation and the convergence of prescribed order, (b) a second-order particle-based algorithm that reduces to the first-order upwind method at local extremal points, providing accuracy and long term stability, and (c) more accurate resolution of entropy discontinuities and states at free interfaces. While the method is consistent and convergent to a prescribed order, the conservation of momentum and energy is not exact and depends on the convergence order. The method is generalizable to coupled hyperbolic–elliptic systems. Numerical verification tests demonstrating the convergence order are presented as well as examples of complex multiphase flows.
Probing light gauge bosons in tau neutrino experiments

The tau neutrino is probably the least studied particle in the standard model (SM), with only a handful of interaction events being identified so far. This can in part be attributed to their small production rate in the SM, which occurs mainly through ${D}_{s}$ meson decay. However, this also makes the tau neutrino flux measurement an interesting laboratory for additional new physics production modes. In this study, we investigate the possibility of tau neutrino production in the decay of light vector bosons. We consider four scenarios of anomaly-free $U(1)$ gauge groups corresponding to the $B\ensuremath{-}L$, $B\ensuremath{-}{L}_{\ensuremath{\mu}}\ensuremath{-}2{L}_{\ensuremath{\tau}}$, $B\ensuremath{-}{L}_{e}\ensuremath{-}2{L}_{\ensuremath{\tau}}$, and $B\ensuremath{-}3{L}_{\ensuremath{\tau}}$ numbers, analyze current constraints on their parameter spaces, and explore the sensitivity of DONuT as well as the future emulsion detector experiments $\mathrm{FASER}\ensuremath{\nu}$, SND@LHC, and SND@SHiP. We find that these experiments provide the leading direct constraints in parts of the parameter space, especially when the vector boson's mass is close to the mass of the $\ensuremath{\omega}$ meson.
Treatment of ST-segment elevation myocardial infarction during COVID-19 pandemic.

The number of cases of the coronavirus-induced disease-2019 (COVID-19) continues to increase exponentially worldwide. In this crisis situation, the management of ST-segment elevation myocardial infarction (STEMI) is challenging. In this review, we outline the risks and benefits of primary PCI vs. thrombolysis for STEMI. While thrombolysis may seem like a good choice, many patients have a contraindication and could end up using more resources. Also, with a high probability of the angiogram showing non-obstructed coronary arteries during acute infections, primary PCI should be the preferred strategy.
Time Out of Control

This chapter examines time as a complex aspect of air mobility. It suggests that the irritating experience of demand for punctuality and agonizing delays, along with the phenomenon of jet lag associated with traveling across multiple time zones, characterize the disordered perception of time in the Airworld. It also shows how the kaleidoscopic and chaotic representation of time produces unique outcomes in contemporary air travel fiction. Writers, artists, and filmmakers juggle multiple layers of time, which they compress, expand, and suspend, producing unique configurations and temporal experiences for their characters.
Drug Targeting via Platelet Membrane-Coated Nanoparticles

Platelets possess distinct surface moieties responsible for modulating their adhesion to various disease-relevant substrates involving vascular damage, immune evasion, and pathogen interactions. Such broad biointerfacing capabilities of platelets have inspired the development of platelet-mimicking drug carriers that preferentially target drug payloads to disease sites for enhanced therapeutic efficacy. Among these carriers, platelet membrane-coated nanoparticles (denoted 'PNPs') made by cloaking synthetic substrates with the plasma membrane of platelets have emerged recently. Their 'top-down' design combines the functionalities of natural platelet membrane and the engineering flexibility of synthetic nanomaterials, which together create synergy for effective drug delivery and novel therapeutics. Herein, we review the recent progress of engineering PNPs with different structures for targeted drug delivery, focusing on three areas, including targeting injured blood vessels to treat vascular diseases, targeting cancer cells for cancer treatment and detection, and targeting drug-resistant bacteria to treat infectious diseases. Overall, current studies have established PNPs as versatile nanotherapeutics for drug targeting with strong potentials to improve the treatment of various diseases.
Adding the Humanities into Math Curriculum Development: A UX Study on Writing Mathematical Arguments

In this paper, we report on a longitudinal benchmark study of student ability to write mathematical arguments in an advanced mathematics course redesigned with input from a team of researchers in the arts and humanities. To track student progress and experience, researchers from mathematics, humanities, and UX/technical communication departments distributed and collected assessments given at the beginning and end of nine sections over one academic year. Each semester, approximately half the courses were taught using the new curriculum and the other half used the original one. Assessment one demonstrated that the new curriculum does significantly increase students’ improvement between beginning and end assessments, whereas the original curriculum did not. Assessment two demonstrated that students felt the new curriculum integrated the course material and assignments more than the existing curriculum and also reported a more enjoyable experience. Assessment three demonstrated that instructors generally feel that the new curriculum aids students’ participatory education and allows them to confront difficult concepts in a more agile environment and cooperative atmosphere. Therefore, we argue for more collaboration inside a STEAM-environment for the mutual benefit of implementing curricular development inspired by Arts and Humanities pedagogy.
Semiconductor to metal transition in the solids/melts of Te and pseudo-binary of Hg1−xCdxTe for x = 0, 0.1, and 0.2

This paper reports the experimentally measured thermal and electrical conductivities from which the Lorenz numbers as functions of temperature were derived for the solids and melts of elemental Te and samples of Hg1−xCdxTe of x = 0, 0.1, and 0.2. The structural changes in the vicinity of the solid–liquid phase transition of elemental Te and various Hg1−xCdxTe solid solutions were assessed by closely examining these experimental properties and the derived Lorenz numbers. The values of Lorenz numbers for the solids of these samples were higher than the value of L0, i.e., the Lorenz number for the free-electron gas derived by Sommerfeld [Naturwissenschaften 15, 825 (1927)], implying the characteristics of a non-degenerate semiconductor. With the increasing value of x, or the larger bandgap, the materials become more non-degenerate with larger deviation from L0. As the solids started to melt, the measured values of the Lorenz number for all samples started to decrease and eventually reached and maintained at values close to L0 at higher temperatures. The trend of the Lorenz number indicates the transition from a non-degenerate semiconductor of the solid samples to a metal or degenerate semiconductor when the temperatures of the samples reached above their liquidus temperatures.
Resting heart rate as a surrogate for improvement in intermediate risk pulmonary embolus patients

Abstract Background Pulmonary embolism (PE) response teams (PERT) have been developed to improve in-hospital mortality. Identifying intermediate risk PE patients that will progress despite anticoagulation is difficult, especially because outcomes with modern anticoagulation are quite good. Objective The primary aim of this study was to evaluate the rate of anticoagulation failure (new deep vein thrombosis or PE, right ventricular failure resulting in shock, cardiac arrest, or PE-attributable death) in intermediate risk PE patients managed by PERT. The secondary objective was to determine whether there was a significant decrease in heart rate 24 h after initiation of anticoagulation in intermediate risk PE. Methods This was a retrospective observational study of patients treated for acute intermediate risk PE at the University of Rochester Medical Center who also had outpatient followup between November 2016–June 2019. Results Ninety-two patients presented as intermediate-risk PE and had outpatient followup. Seventy-four patients were initially treated with anticoagulation. None of these patients failed anticoagulation. Of the eighteen intermediate risk patients that underwent advanced intervention, none failed anticoagulation first. There was significant decrease in resting heart rate 24 h after starting therapeutic anticoagulation, 107 beats/min vs 89 beats/min, p = 0.0001. Conclusion We did not observe anticoagulation failure in the management of acute, intermediate risk PE. Reductions in heart rate may reflect improvements in right ventricular function; we hypothesize that those whose heart rate does not fall may be optimal candidates for advanced intervention.
Soil Science Contribution to an Airplane Crash Investigation, Ruidoso, New Mexico

Investigation of a plane crash near Ruidoso, New Mexico revealed foreign biological material and soil in the fuel system of the engine. In-flight accumulation of the soil was claimed by the plaintiffs as one cause for the crash. EDX X-ray maps and spectra were taken by the plaintiff's experts and showed patterns consistent with silicates. The defense hypothesis was that the soil accumulated after the crash while the debris was in a storage yard and exposed to the elements for several months. Many of the parts were covered in muddy water (mud puddles) before the plaintiffs investigated the parts for soil accumulation. The soil composition on the parts was found to be similar to that in the storage yard. Further, the plane was exposed to an intense fire after the crash, and if the soil had been subjected to such temperatures it would have oxidized to a red color. Soil from the storage yard, the crash site, and from an area in Montana where the plane landed on an unpaved runway was exposed to heat up to 1,000°C in the laboratory and the soil turned red. Soil from the fuel component was not red, although a small piece adhering to the outside of the wreckage was red suggesting exposure to the post-crash fire. It was concluded that the engine parts were contaminated with soil after the crash, and that pre-crash accumulation of soil, as a supplement or alternative to biological contamination, was not a viable explanation.
Occult Communications: On Instrumentation, Esotericism, and Epistemology

Viewed from the perspective of the occult, formerly straight and narrow conduits of reason may even begin to resemble irregular relays composed of irregular twists and turns. This essay offers a brief overview of key literature on spiritualism and the occult, some larger reflections on the place of the occult within studies of science and communications, and brief summaries of the essays contained in this volume.
Effects of fluoride on magnesium deficiency in the guinea pig.

Experiments were conducted with young growing guinea pigs to study the magnesium :fluoride relationship at several dietary levels of magnesium and of fluoride. Addition of fluoride (100 or 200 ppm) to a diet suboptimal in magnesium (0.04% ) alleviated soft tissue calcinosis. The effect was evident after 6 and 12 weeks of feeding and appeared to be mediated through a sparing of the magnesium require ment. Growth depression, serum magnesium decrease, and bone magnesium loss were moderated by fluoride addition to the low magnesium diet. The magnesium-sparing and anticalcinatory effects of fluoride were less pronounced in animals fed 0.009% magnesium. A higher level of fluoride (300 ppm) was toxic to guinea pigs fed the low magnesium (0.04% ) diet, but not to those fed 0.21% magnesium. Magnesium deficiency was associated with an increase in heart potassium content which was retarded by 100 ppm dietary fluoride. In comparison with data reported previously, species differences are apparent in the magnesium:fluoride interrelationship between the guinea pig, dog and rat.
Unique glycosylation of three keratan sulfate proteoglycan isoforms

Recent work demonstrates isoforms of bovine corneal keratan sulfate proteoglycan containing structurally unique core proteins of 25 and 37 kDa (Funderburgh, J., and Conrad, G. (1990) J. Biol. Chem. 265, 8297-8303). In the current study, two forms (37A and 37B) of the 37-kDa protein were separated by ion-exchange chromatography after removal of keratan sulfate with endo-beta-galactosidase. Keratan sulfate linkage sites in core proteins were labeled with UDP-[3H]galactose using galactosyltransferase. Labeled proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and analyzed by tryptic digestion and reversed-phase chromatography. The 37A protein has three keratan sulfate-linkage sites, and the 37B and 25-kDa proteins each contain one linkage site. Reversed-phase tryptic maps of the three proteins differed in total peptide profile and in glycosylated peptides labeled with periodate-[3H]-NaBH4. Tryptic mapping of the two 37-kDa isoforms after deglycosylation showed differences in total tryptic peptides, in peptides labeled with [14C]iodoacetic acid, and in peptides recognized by antibodies to a mixture of the 37-kDa cores. Antibody to a synthetic peptide with N-terminal sequence obtained from mixed 37-kDa cores reacted exclusively with the 37B isoform. These results show that bovine corneal keratan sulfate proteoglycan has three different core proteins each with distinct glycosylation and unique primary structure.
Magnetic Fields in Clusters: Theory vs. Observations

It is now well established that the plasma in galaxy clusters is magnetized. In some cases, at least, the field is strong enough to be dynamically important. Perhaps this is the time to move past simple detection experiments, and to work towards a general understanding of the strength, structure and maintenance of the cluster field.
Durability Studies of Hybrid Composite of E-Glass/Carbon Fibers in Different Solvents for Bridge Deck Panel Application

Objective An experimental study was carried out to investigate the solvent uptake in E-glass/Carbon Fiber composites with two types of epoxy systems: SC-15 and 635 epoxy resins in water, saltwater and antifreeze. These resins were infused into carbon, E glass and a hybrid of carbon and E-glass fabrics. Unconditioned samples with 635 epoxy resin system showed better flexural properties in case of both carbon fiber and hybrid composites but poor response when used as a matrix for E-glass fibers compared to SC-15 epoxy resin. Flexural properties for conditioned samples were determined after an immersion period of 8 weeks at room temperature and results showed that the 635 epoxy resin has a poor retention of flexural properties compared to SC-15 epoxy resin with highest degradation recorded for samples fabricated using E-glass fabrics. Moisture absorption curves did not follow the Fick’s law of diffusion except for first week of immersion. Lowest solvent uptake was recorded in antifreeze while highest was recorded in saltwater. Low operation temperature was exhibited by 635 epoxy resin with lower values of glass transition temperature compared to SC-15 epoxy resin. Storage modulus and glass transition temperatures determined from dynamic mechanical analysis (DMA) showed that composites with 635 epoxy resin system had better storage modulus while those with SC-15 had higher glass transition temperatures. Highest degradation in storage modulus was seen in E-glass-635 epoxy samples when conditioned with salt water while the maximum reduction in the glass transition temperature was seen for E-glass-635 epoxy samples conditioned with water.Copyright © 2014 by ASME
Rockel Stephen J.. Carriers of Culture: Labor on the Road in Nineteenth-Century East Africa. Portsmouth, N.H.: Heinemann, 2006. Social History of Africa Series, xix + 345 pp. Photographs. Illustrations. Maps. Tables. Notes. Bibliography. Index. $124.95. Cloth. $29.95. Paper.

Stephen J. Rockel. Carriers of Culture: Labor on the Road in NineteenthCentury East Africa. Portsmouth, N.H.: Heinemann, 2006. Social History of Africa Series, xix + 345 pp. Photographs. Illustrations. Maps. Tables. Notes. Bibliography. Index. $124.95. Cloth. $29.95. Paper. In this critical addition to East African historiography, Stephen Rockel brings together social, economic, and cultural history sensibilities to produce a compelling foundational work on East African caravan porter culture. Long-distance trading networks linked East Africa's interior with the global trading system and enabled all manner of European interventions in the continent; it is no exaggeration to say that these trade networks would have been impossible without porters: "Without porters, nothing would have moved" (4). Nonetheless, "the omnipresent porter has become almost invisible [in African historiography] "(5). To reconstruct the social history of this vital group, Rockel expertly synthesizes an impressive array of evidence-oral interviews, colonial documents, mission materials (though he seems not to have used any archives in Germany), and published memoirs by well-known European explorers. Layers of misconceptions abound on caravan culture, perpetuated by imperialist and humanitarian defenders of European antislavery interventions in East Africa and by subsequent historians who uncritically accepted these perspectives. Rockel's careful study shows that East African porters were by and large not captives, as the "slave myth" asserts, but professionals who participated in an emergent migrant wage labor culture and economy, driven by both external demand and internal precedent. Indeed, his careful work challenges previous scholarship that depicts African porters as social climbers, slaves, or unaware individuals (usually men) who responded blindly to the capitalist juggernaut without concern for collective working conditions, wage levels, or professional standards. Instead, he argues convincingly that caravan porters creatively engaged with a "translated modernity" (10), within which they "develop [ed] a transitional form of wage labor shaped by indigenous precapitalist labor norms but closely linked to merchant capital and the global economy "(6). Rockel likens caravan culture to the "crew culture" (23-28) of sailing ships, which functioned through recognition of common ethics, honor codes, and customary practices to protect group members as they carried out their dangerous work. Emphasizing mobility as a defining cultural factor, diis comparison underscores the fusion of global economic imperatives with local cultural initiatives in die development of professional caravan culture. …
Rural Revitalization in New Mexico: A Grass Roots Initiative Involving School and Community.

The Rural Education Bureau of the New Mexico Public Education Department has established a program to address the special needs of schools and communities in the extensive rural areas of the state. High poverty rates, depopulation and a general lack of viable economic opportunity have marked rural New Mexico for decades. The program underway aims at establishing holistic community socioeconomic revitalization at the grass roots level with the schools playing a leading role. Initiatives include community conversations with key leaders to determine necessary steps to take in encouraging economic growth and attracting businesses, the institution of entrepreneurship within the community, the transformation of the school into a community resource and the encouragement of place-based education within schools. In the second year of this program there are 13 school districts actively involved in the enhancement of their schools and community. The program adopted many of the principles for rural revitalization seen in the remote communities of South Australia.
Infinite Dimensional Lie Algebras

Introduction Notational conventions 1. Basic definitions 2. The invariant bilinear form and the generalized casimir operator 3. Integrable representations of Kac-Moody algebras and the weyl group 4. A classification of generalized cartan matrices 5. Real and imaginary roots 6. Affine algebras: the normalized cartan invariant form, the root system, and the weyl group 7. Affine algebras as central extensions of loop algebras 8. Twisted affine algebras and finite order automorphisms 9. Highest-weight modules over Kac-Moody algebras 10. Integrable highest-weight modules: the character formula 11. Integrable highest-weight modules: the weight system and the unitarizability 12. Integrable highest-weight modules over affine algebras 13. Affine algebras, theta functions, and modular forms 14. The principal and homogeneous vertex operator constructions of the basic representation Index of notations and definitions References Conference proceedings and collections of paper.
Poisson structure and invariant manifolds on Lie groups

For a discrete mechanical system on a Lie group G determined by a (reduced) Lagrangian l we define a Poisson structure via the pull-back of the Lie-Poisson structure on g^∗ by the corresponding Legendre transform. The main result shown in this paper is that this structure coincides with the reduction under the symmetry group G of the canonical discrete Lagrange 2-form ω_L on G × G. Its symplectic leaves then become dynamically invariant manifolds for the reduced discrete system.
Dependence of the relative sensitivity factor of nitrogen on various oxynitride dielectric matrixes

Abstract The relative sensitivity factor (RSF) plays a critical role in the quantification of nitrogen concentration in oxynitride gate oxide measured using secondary ion mass spectrometry (SIMS). The RSF depends primarily on the matrixes where the nitrogen resides under conditions in which the parametric settings of the SIMS equipment remain unchanged. In this article, different types of oxynitride dielectric films have been prepared under several different fabrication processes including decoupled plasma nitridation, thermal nitridation by nitric oxide (NO) and nitrous oxide (N 2 O), which resulted in the formation of significantly different chemical bonding and micro-structures for the oxynitride. The nitrogen RSF values of these oxynitride films were determined using the ratio of the species SiN − and 30 Si − from the Time-of-Flight SIMS. It was found that the overall RSF values from the point-by-point algorithm ranged from 1.15 × 10 21 to 2.41 × 10 21 atoms/cm 3 . These account for about 2 times the difference in the RSF values.
Packing conflicts in the Z′ = 5 structure of CF3(CF2)3(CH2)10COOH

Dimers of the partially fluorinated amphiphile 1-(perfluoro­butyl)undecanoic acid, CF3(CF2)3(CH2)10COOH, crystallize in the same basic packing arrangement found for many n-alkyl carboxylic acids. The unit cell of the fluorinated compound, however, contains five independent molecules rather than the one found for most n-alkyl carboxylic acids including CH3(CH2)13COOH. The structures of the two C15 acids are compared. The structural modulations that lead to the large value of Z′ can be understood as resulting from the conflict between the necessity of filling space densely and uniformly and the tendency of unlike groups to be segregated spatially. The few other known structures of compounds with both (CF2)n and (CH2)m regions show evidence of the same conflict.
Vascular Morphogenesis and the Formation of Vascular Networks

A recent workshop organized by Luisa Iruela-Arispe and Brant Weinstein and sponsored by the North American Vascular Biology Organization (NAVBO) brought 200 developmental biologists together at the Asilomar Conference Center in Pacific Grove, California, to share some of their latest findings. This superb meeting synthesized data from a variety of model systems ranging from Urbilateria (a common ancestor to vertebrates and invertebrates), fruit flies, frogs, zebrafish, and mice to human genetic disorders. Participants enjoyed lively discussions on developmental vascular biology while experiencing the natural beauty of the Pacific Coast.
Investigation Into Cumulative Damage Rules to Predict Fretting Fatigue Life of Ti-6Al-4V Under Two-Level Block Loading Condition

The effects of variable amplitude loading on fretting fatigue behavior of titanium alloy Ti-6Al-4V were examined. Fretting fatigue tests were carried out under constant stress amplitude and three different two-level block loading conditions: high-low (Hi-Lo), low-high (Lo-Hi), and repeated block of high and low stress amplitudes. The damage fractions and fretting fatigue lives were estimated by linear and non-linear cumulative damage rules. Damage curve analysis (DCA) and double linear damage rule (DLDR) were capable to account for the loading order effects in Hi-Lo and Lo-Hi loadings. In addition, the predictions by DCA and DLDR were better than that by linear damage rule (LDR). Besides its simplicity of implementation, LDR was also capable of estimating failure lives reasonably well. Repeated two-level block loading resulted in shorter lives and lower fretting fatigue limit compared to those under constant amplitude loading. The degree of reduction in fretting fatigue lives and fatigue strength depended on the ratio of cycles at lower stress amplitude to that at higher stress amplitude. Fracture surface of specimens subjected to Hi-Lo and repeated block loading showed the clear evidence of change in stress amplitude of applied load. Especially, the repeated two-level block loading resulted in characteristic markers which reflected change in crack growth rates corresponding to different stress amplitudes.
Mechanism of enhanced sensitivity of linear poly(ethylenimine)-carbon black composite detectors to carboxylic acid vapors

Abstract Enhanced sensitivity towards volatile carboxylic acid vapors is obtained when the basic, amine-containing polymer, linear poly(ethylenimine), l -PEI, is used as the insulating component in a carbon black-polymer composite vapor detector. Specifically, at a partial pressure of analyte corresponding to 1% of its vapor pressure at room temperature, the signal-to-noise ratio for detection of acetic acid is 10 3 times larger than that for non-acidic organic vapors. Measurements of the mass uptake, thickness change, and electrical conductivity of such composites have been performed to elucidate the mechanism of this sensitivity enhancement towards volatile carboxylic acid vapors. These data have allowed quantification of the relative contributions of electrical percolation effects, increases in analyte sorption, and charge-induced swelling effects in determining the response characteristics of l -PEI composites.
Do Ranger Stations Deter Poaching Activity in National Parks in Thailand

As protected areas become more accessible via transportation networks, fragmentation, and encroachment from the borders, carnivores in these areas frequently decline. To counter these pressures, patrolling and active wildlife enforcement are widely accepted as fundamental conservation strategies. Using the case example of Khao Yai National Park (KYNP) and data from a camera trap survey, we modeled and evaluated the effectiveness of ranger stations in reducing human access and illegal activities, and in increasing prey and predator presence. This type of data and analysis is needed to monitor and evaluate enforcement effectiveness and develop adaptive management strategies. At KYNP, we used camera-trapping data as a proxy to evaluate whether or not a positive impact of ranger stations on wildlife distribution could outweigh edge effects from human disturbance. We assessed factors affecting the distribution of poachers and wildlife using Maxent. Our analysis was based on 217 camera trap locations (6260 trap nights) and suggests that ungulates and poachers persist nearby ranger stations. Rangers should increase patrolling efforts of border areas; however, increasing wildlife patrolling in inaccessible areas with mobile range units may be more effective than establishing more ranger stations along park boundaries.
Interpretation of Flow Reactor Based Ignition Delay Measurements

Compositional variation of global gas supplies is becoming a growing concern. Both the range and rate-of-change of this variation is expected to increase as global markets for Liquefied Natural Gas (LNG) continue to expand. Greater fuel composition variation poses increased operational risk to gas turbine engines employing lean premixed combustion systems. Information on ignition delay at high pressure and intermediate temperatures is valuable for lean premixed gas turbine design. In order to avoid autoignition of the fuel/air mixture within the premixer, the ignition delay time must be greater than the residence time. Evaluating the residence time is not a straight forward task because of the complex aerodynamics due to recirculation zones, separation regions, and boundary layers effects which may create regions where the local residence times may be longer than the bulk or average residence time. Additionally, reliable experiments on ignition delay at gas turbine conditions are difficult to conduct. Devices for testing include shock tubes, rapid compression machine and flow reactors. In a flow reactor ignition delay data are commonly determined by measuring the distance from the fuel injector to the reaction front (L) and dividing it by the bulk or average flow velocity (U) under steady flow conditions to obtain a bulk residence time which is assumed to be equal to the ignition delay time. However this method is susceptible to the same boundary layer effects or recirculation zones found in premixers. An alternative method for obtaining ignition delay data in a flow reactor is presented herein, where ignition delay times are obtained by measuring the time difference between fuel injection and ignition using high speed instrumentation. Ignition delay times for methane, ethane and propane at gas turbine conditions were in the range of 40–500 ms. The results obtained show excellent agreement with recently proposed chemical mechanisms for hydrocarbons at low temperature/high pressure conditions.Copyright © 2009 by ASME
The α7β1 Integrin Mediates Adhesion and Migration of Skeletal Myoblasts on Laminin

Abstract Many aspects of myogenesis are believed to be regulated by myoblast interactions with specific components of the extracellular matrix. For example, laminin has been found to promote adhesion, migration, and proliferation of mammalian myoblasts. Based on affinity chromatography, the α7β1 integrin has been presumed to be the major receptor mediating myoblast interactions with laminin. We have prepared a monoclonal antibody, O26, that specifically reacts with both the X1 and the X2 extracellular splice variants of the α7 integrin chain. This antibody completely and selectively blocks adhesion and migration of rat L8E63 myoblasts on laminin-1, but not on fibronectin. In contrast, a polyclonal antibody to the fibronectin receptor, α5β1 integrin, blocks myoblast adhesion on fibronectin, but not on laminin-1. The α7β1 integrin also binds to a mixture of laminin-2 and laminin-4, the major laminin isoforms in developing and adult skeletal muscle, but O26 is a much less potent inhibitor of myoblast adhesion on the laminin-2/4 mixture than on laminin-1. Based on affinity chromatography, we suggest that this may be due to higher affinity binding of α7X1 to laminin-2/4 than to laminin-1.
Immunocompetent cells of the chicken. I. Specific surface antigenic markers on bursa and thymus cells.

Specific antisera to chicken thymus and to bursa of Fabricius were obtained in rabbits. After appropriate absorption and dilution all four anti-thymus sera, in the presence of guinea pig C', killed >90% of thymus and 90% of bursa cells and <==10% of thymus cells. These antisera were cytotoxc for a large percentage of antibody-forming cells and killed approximately 30% of spleen cells The other two anti-bursa sera were somewhat less potent but showed similar specificity. The surface antigen detected by these antisera was named chicken bursa-derived lymphocyte antigen (CBuLA). Rabbit antisera to chicken immunoglobulin were cytotoxic for bursa but not for thymus cells and killed a similar percentage of spleen cells as did anti-bursa sera. They were also cytotoxic for antibody-forming cells.
Ability of the Listeria monocytogenes strain Scott A to cause systemic infection in mice infected by the intragastric route.

Listeriosis is an important food-borne disease that causes high rates of morbidity and mortality. For reasons that are not clear, most large outbreaks of human listeriosis involve Listeria monocytogenes serotype 4b. Relatively little is known about the pathogenesis of listeriosis following gastrointestinal exposure to food-borne disease isolates of L. monocytogenes. In the present study, we investigated the pathogenesis of systemic infection by the food-borne isolate Scott A in an intragastric (i.g.) mouse challenge model. We found that the severity of infection with L. monocytogenes Scott A was increased in mice made neutropenic by administration of monoclonal antibody RB6-8C5. This observation was similar to a previous report on a study with the laboratory strain L. monocytogenes EGD. Prior administration of sodium bicarbonate did not enhance the virulence of L. monocytogenes strain Scott A for i.g. inoculated mice. Following i.g. inoculation of mice, two serotype 4b strains of L. monocytogenes (Scott A and 101M) achieved a greater bacterial burden in the spleen and liver and elicited more severe histopathological damage to those organs than did a serotype 1/2a strain (EGD) and a serotype 1/2b stain (CM). Of the four strains tested, only strain CM exhibited poor survival in synthetic gastric fluid in vitro. The other three strains exhibited similar patterns of survival at pHs of greater than 5 and relatively rapid (<30 min) loss of viability at pHs of less than 5.0. Growth of L. monocytogenes Scott A at temperatures of 12.5 to 37 degrees C did not affect its ability to cause systemic infection in i.g. inoculated mice. These observations suggest that the serotype 4b L. monocytogenes strains Scott A and 101M possess one or more virulence determinants that make them better able to cause systemic infection following inoculation via the g.i. tract than do the serotype 1/2 strains EGD and CM.
Activity limitation, chronic disease, and comorbid serious psychological distress in U.S. adults--BRFSS 2007.

Objectives: This study examines the prevalence of self-reported activity limitation from poor physical or mental health in the past 30 days among a sample of noninstitutionalized U.S. adults. The associations between frequent activity limitation, chronic diseases, and comorbid serious psychological distress (SPD) were also examined.
Carbon Isotope Fractionation in the System CO 2 (gas)—CO 2 (aqueous)—HCO 3 − (aqueous)

Carbon isotope fractionation between gaseous carbon dioxide and aqueous bicarbonate decreases from 9.2 to 6.8 parts per thousand over the temperature range 0°–30° C. This fractionation occurs in the hydration stage, not in the passage of atmospheric carbon dioxide through the air–water interface.