cssi/SciSciGPT-SciSciNet huggingface dataset:
Studies of Archaebacterial Bipolar Tetraether Liposomes by Perylene Fluorescence

Membrane packing and dynamics of bipolar tetraether liposomes composed of the polar lipid fraction E (PLFE) from the thermoacidophilic archaebacterium Sulfolobus acidocaldarius have been studied by perylene fluorescence. At a probe-to-PLFE lipid ratio of 1:400, we have detected an unusual fluorescence intensity increase with increasing temperature, while the fluorescence lifetime changed little. As the ratio was decreased, the intensity anomaly was diminished. At 1:3200 and 1:6400, the anomaly disappeared. A remarkable perylene intensity anomaly was also observed in bilayers composed of saturated monopolar diester phosphatidylcholines at their main phase transition temperatures. These results suggest that the intensity anomaly may be due to probe aggregation caused by tight membrane packing. At the same probe-to-lipid ratio (1:400), however, 1, 2-diphytanoyl-sn-glycero-3-phosphocholine (DPhPC) and 1, 2-diphytanoyl-sn-glycero-3-phosphoglycerol (DPhPG) liposomes did not exhibit any intensity anomaly with increasing temperature. This suggests that DPhPC and DPhPG liposomes are more loosely packed than PLFE liposomes; thus the branched methyl groups are not the contributing factor of the tight membrane packing found in PLFE liposomes. Using a multiexcitation method, we have also determined the average (R), in-plane (R(ip)), and out-of-plane (R(op)) rotational rates of perylene in PLFE liposomes at various temperatures (20-65 degrees C). R and R(ip), determined at two different probe-to-lipid ratios (1:400 and 1:3200), both undergo an abrupt increase when the temperature is elevated to approximately 48 degrees C. These data suggest that PLFE liposomes are rigid and tightly packed at low temperatures, but they begin to possess appreciable "membrane fluidity" at temperatures close to the minimum growth temperature ( approximately 50 degrees C) of thermoacidophilic archaebacteria.
Development and Testing of the Survey of Illness Beliefs in Heart Failure Tool

This study establishes reliability and construct validity of the Survey of Illness Beliefs in Heart Failure (HF) tool, which measures the accuracy and certainty of illness beliefs people have about HF. Factor analysis produced a 2-component structure of 14 items that revealed accurate and inaccurate illness beliefs (alpha=0.87 and 0.71, respectively). Construct validity was supported with significantly greater accuracy in illness belief scores in patients evaluated or listed for heart transplantation or enrolled in an HF research study (P=.008 and .02, respectively). The reliability and validity of the tool is sufficient to support its use in clinical research.
Validity of the bilinear rate equation for exciton annihilation and expressions for the annihilation constant

The validity of the well-known bilinear rate equation, used for the interpretation of exciton annihilation observations in molecular crystals, is examined on the basis of a recently constructed exact theory of the annihilation process. Experimentally attainable situations, in which the traditional equation is not applicable, are pointed out and alternative equations are given for use in such cases. Explicit expressions for the annihilation constant γ are given for situations in which the usual rate equation is applicable.
Baseline shifts do not predict attentional modulation of target processing during feature-based visual attention

Cues that direct selective attention to a spatial location have been observed to increase baseline neural activity in visual areas that represent a to-be-attended stimulus location. Analogous attention-related baseline shifts have also been observed in response to attention-directing cues for non-spatial stimulus features. It has been proposed that baseline shifts with preparatory attention may serve as the mechanism by which attention modulates the responses to subsequent visual targets that match the attended location or feature. Using functional MRI, we localized color- and motion-sensitive visual areas in individual subjects and investigated the relationship between cue-induced baseline shifts and the subsequent attentional modulation of task-relevant target stimuli. Although attention-directing cues often led to increased background neural activity in feature specific visual areas, these increases were not correlated with either behavior in the task or subsequent attentional modulation of the visual targets. These findings cast doubt on the hypothesis that attention-related shifts in baseline neural activity result in selective sensory processing of visual targets during feature-based selective attention.
Is phase-shift mask technology production-worthy?

The feasibility and potential of Phase-Shift Mask (PSM) for sub- 0.5 urn fabrication have been clearly demonstrated. In the '91 SPIE Microlithography Syrnposium, a total of 18 papers on PSM were presented. Many new, innovative designs have been proposed. However, there is still a myriad of technical and logistic problems, which must be resolved for production implementation. We organized the workshop and panel discussion in the hope that the participants would collectively make an assessment of the maturity of the technology and reach a common understanding of the key issues.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Effects of various RIE process-induced damages on MOSFET characteristics

A systematic study of the degradation of MOSFETs performance and reliability caused by various reactive ion etching (RIE) process steps are conducted. It is found that the polysilicon RIE process significantly increases the electron trapping as an active damage, thus causing higher initial V t and lower initial G m of NMOSFETs. In addition, while NMOSFETs with via antenna structures show largest RIE- induced degradation compared to other antenna devices. Our results also indicate Fowler-Nordheim stress results are well correlated with those from hot carrier stressing for monitoring RIE-induced latent damages, suggesting that Fowler-Nordheim stress is an efficient method to monitor RIE damage in a short time.
Errors in extension measurements from planar faults observed on seismic reflection lines

The preferred model for the extension of brittle crust involves the rotation of planar fault blocks. We show that in general the distortion at the ends of the blocks does not affect the measurement of extension. The horizontal displacement on a normal fault, the heave, is observed with little distortion on a seismic reflection time-section. It can be used to estimate the amount of extension. We demonstrate that the sum of the heaves is not equal to the actual elongation if the blocks have rotated. However, the error in the extension factor, β, introduced by equating elongation with the sum of the heaves is small. It increases with the amount of rotation from 0 for no rotation to 13% for the maximum observed angle of rotation of 30o. We compare this value with the practical error introduced by uncertainties in seismic velocities when the elongation is measured from a depth-converted seismic section. This latter error is significantly smaller being approximately 5% for an error in velocity of 20% when the rotation angle is less than 30o.
Problems and Benefits Reported by Stroke Family Caregivers. Results From a Prospective Epidemiological Study

Background and Purpose— Stroke symptoms can be very stressful for family caregivers, but most knowledge about the prevalence and stressfulness of stroke-related patient problems is derived from convenience samples. In addition, little is known about perceived benefits of the stroke caregiving experience. The purpose of this study was to determine the prevalence and stressfulness of stroke-related problems, and perceived benefits of caregiving, as reported by an epidemiologically derived sample of caregivers of stroke survivors. Methods— Stroke survivors (N=75) from a prospective epidemiological study of stroke, the REasons for Geographic and Racial Differences in Stroke (REGARDS) study, and their family caregivers were followed. Caregivers were given a comprehensive telephone interview 8 to 12 months after the stroke, using measures of stroke patient problems, caregiver appraisals of the stressfulness of these problems, and perceived benefits of caregiving. Results— Caregivers rated patient problems with ...
The formation and dynamics of proton wires in channel environments.

Abstract By virtue of an accurate interaction model, the equilibrium and dynamical properties of an excess proton in aqueous systems are studied, in which the water and excess proton are confined to hydrophobic cylindrical channels. Solvation structures of the excess proton and its mobility along the channel are considered as a function of the channel radius. It is found that when the aqueous proton systems are sufficiently constricted there is a substantial increase in the diffusion of the excess proton charge accompanied by a decrease in the diffusion of water molecules along the channel. Such systems present clear evidence for the possible existence of "proton wires."
Hollow fiber contained liquid membrane separation of citric acid

Citric acid was successfully separated from an aqueous solution using the hollow fiber contained liquid membrane (HFCLM) technique. In this technique, the organic liquid membrane is contained in the shell side between two sets of hollow fibers; feed solution flows through one set of fibers and the strip solution flows through the other set. Tri-n-octylamine diluted in various organic solvents was used as a complexing agent for facilitated transport of citric acid from an aqueous solution. Pure water and aqueous sodium hydroxide were used as stripping agents. Membrane life and stability problems encountered in supported liquid membranes are eliminated. A mathematical model of facilitated solute transport through HFCLM that accounts for the interfacial reversible reaction kinetics and diffusion process inherent in carrier-facilitated transport is presented. Experimental data agreed well with the theoretical predictions for permeators achieving almost complete solute recovery.
Effect of donor (I) or acceptor (N) co-doping on Cr doped (ZnTe)12 clusters

Abstract We report a first principles density functional theory in the local spin density approximation study of the energetics and the magnetism of (ZnTe) 12 clusters, doped with the transition metal Cr along with impurities of either acceptor or donor types, and their effect on the energetics and local as well as global magnetism in the clusters.
Densified biomass can cost-effectively mitigate greenhouse gas emissions and address energy security in thermal applications

Regional supplies of biomass are currently being evaluated as feedstocks in energy applications to meet renewable portfolio (RPS) and low carbon fuel standards. We investigate the life cycle greenhouse gas (GHG) emissions and associated abatement costs resulting from using densified switchgrass for thermal and electrical energy. In contrast to the large and positive abatement costs for using biomass in electricity generation ($149/Mg CO2e) due to the low cost of coal and high feedstock and power plant operation costs, abatement costs for replacing fuel oil with biomass in thermal applications are large and negative (−$52 to −$92/Mg CO2e), resulting in cost savings. Replacing fuel oil with biomass in thermal applications results in least cost reductions compared to replacing coal in electricity generation, an alternative that has gained attention due to RPS legislation and the centralized production model most often considered in U.S. policy. Our estimates indicate a more than doubling of liquid fuel displ...
Experimental trials of the northern flying squirrel (Glaucomys sabrinus) traversing managed rainforest landscapes: perceptual range and fine-scale movements

Successful dispersal in many species may be a function of the distance at which animals can perceive a particu- lar landscape feature (i.e., perceptual range), as well as energetic costs associated with traversing the distance towards that feature. We used a model, relating perceptual range to body size of mammals, to predict the perceptual range of the north- ern flying squirrel (Glaucomys sabrinus (Shaw, 1801)) in fragmented forests of Southeast Alaska. We hypothesized that the perceptual range of flying squirrels would be 325.5-356.5 m in clearcuts and 159.7-174.9 m in second-growth stands. The distance advantage in clearcuts may, however, be lost if the cost of transport in that habitat is higher. Our results sug- gest that as heuristically predicted by the model, the perceptual range of flying squirrels was greater in clearcut habitats than in second-growth stands. Nonetheless, for both habitats the actual perceptual range was significantly shorter than pre- dicted by the model. We found that precipitation, and associated cloud cover and illumination, and wind speed, which af- fect olfaction capabilities, influenced orientation success. Although squirrels more often oriented towards the forest edge in clearcuts, they paused more often during their movements, which may lead to higher costs of dispersing through this habitat. The application of the mass-based model to nonagricultural landscapes should be done with caution, and variables such as wind and illumination be measured concurrently. Our data illustrate that dispersing squirrels likely will not venture into managed habitats because logging creates clearcuts larger than the perceptual range of these mammals.
Selection for short introns in highly expressed genes.

Transcription is a slow and expensive process: in eukaryotes, approximately 20 nucleotides can be transcribed per second1,2 at the expense of at least two ATP molecules per nucleotide3. Thus, at least for highly expressed genes, transcription of long introns, which are particularly common in mammals, is costly. Using data on the expression of genes that encode proteins in Caenorhabditis elegans and Homo sapiens, we show that introns in highly expressed genes are substantially shorter than those in genes that are expressed at low levels. This difference is greater in humans, such that introns are, on average, 14 times shorter in highly expressed genes than in genes with low expression, whereas in C. elegans the difference in intron length is only twofold. In contrast, the density of introns in a gene does not strongly depend on the level of gene expression. Thus, natural selection appears to favor short introns in highly expressed genes to minimize the cost of transcription and other molecular processes, such as splicing.
Constraint isomorphism and correction algorithms for violations

The issue discussed here may be best understood by a specific case study: the total tardiness problem, an NP-complete job scheduling problem. In this problem, two parameter sets are commonly employed. For easy reference, we call one set “data parameters” and the other “characteristic parameters.” Processing time and due date for each individual job are data parameters, and the tardiness factor, τ, and relative range of due dates, δ, are characteristic parameters. For the simplest, single machine model, each job is processed by the single machine at a time. n jobs wait for processing at time t =0 , and they have processing times p1, p2, ..., pn ,a nddue dates d1, d2, ..., dn, respectively. The objective of the problem is to determine the order of jobs to be processed to minimize the total tardiness.
Economic Models of Speculative Attacks and the Drachma Crisis of May 1994

Speculative attacks on fixed or ‘fixed but adjustable’ exchange rate regimes seem to have become a standard feature of the landscape of foreign exchange markets. The supposed excesses of seemingly untethered financial markets have been documented for some time, but only recently have the concerted attacks by speculators on exchange-rate regimes begun to occupy the popular imagination.Economic models of this phenomenon, however, have been around for some time, and are useful in characterizing the real-world speculative attacks that have occurred in the last 10–15 years in a number of countries. In this paper, we provide a brief overview of one such model. We also sketch some implications of that model for the speculative attack on the Greek drachma in May 1994.
The Predynastic of Egypt

The Predynastic of Egypt, spanning an interval from ca. 4000 to 3050 B.C., was an eventful period. After the inception of food production in the Nile Valley at least a millennium before, it was the time when the identity of Egyptian society was forged. Egypt was settled by refugees from the deserts of the eastern Sahara and the southern Levant, fleeing from mid-Holocene droughts, and became a melting pot of indigenous Nilotes and desert herders, part-time cultivators, and hunters. Within a millennium, an increasing dependence on agriculture led to sedentary life and, in some cases, to the development of sizable communities. By 4000 B.C., the settled communities had also developed a distinct division of labor between men and women and ritual and religious beliefs in which women, grain, fertility, and death were salient and interrelated elements. The Predynastic communities were also faced by the most destabilizing factor of agricultural economy, namely, fluctuations of yield. Attempts to dampen the fluctuations through interregional integration led to the emergence of community representatives and eventually chiefs. Legitimation of the status of chiefs through affiliation with the traditional and supernatural power associated with women, fertility, and death and the acquisition of exotic goods stimulated trade and an industry in funerary goods. Enlargement of economic units through alliances, with occasional incidences of fighting, especially after 3600 B.C., led to the rise of a state society governed by supreme rulers. The wedding of the funerary cult of Late Predynastic Egypt with political power and military might was the basis for the most fascinating aspects of Ancient Egypt—religion and kingship.
The Poetics of Expiration: Felicia Hemans

Hemans’s “poetics of expiration” is contrasted to the high Romantic “poetics of effusion,” the former devoted to insubstantiality, the latter to the monumental. Critics from Walter Scott to Kingsley Amis have berated Hemans’s extreme superficiality, but, as Jerome McGann has argued, it can be seen as her bid to imagine substance on the brink of its dissolution. This essay shows, through careful readings of her poems, that though dissolution and death figure in this poetics of expiration, at its heart is a reversal from “emptying out” to “proliferation.” A dying into the moment has a certain life-yield that Hemans calls “holiness.” Reading not only the reception history of Hemans but also Hemans’s reception of high Romantic poets show us that we have misunderstood her aims: attuning ourselves to her praise for the enactment of her highest poetic goals in poetry by others helps us to see them in her works as well.
Polypyrrolones for membrane gas separations. I. Structural comparison of gas transport and sorption properties

Despite efforts by the membrane community to develop polymeric materials with improved O2/N2 separation performance, limited progress has occurred for almost a decade. Molecular sieving media, which can exhibit gas separation properties superior to polymers, tend to be brittle and uneconomical to produce for large-scale membrane separation processes. Considering this, the polymer structures investigated in this work were designed to mimic aspects of the structure of molecular sieving media such as zeolites and carbon molecular sieves while maintaining the processability associated with polymers. Significantly attractive gas separation material properties were obtained using hyper rigid polypyrrolone copolymers with controlled packing disruptions between flat, packable segments. The gas transport properties in the materials changed dramatically as a result of different average interchain spacing. Moreover, all of the polypyrrolones studied in this work exhibited performance lying on or above the existing O2/N2 upper bound trade-off line between permselectivity and permeability. These results, therefore, may point the way to a new cycle of membrane materials improvements for gas separations. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 1235–1249, 1999
Relativistic reversal of the ponderomotive force in a standing laser wave

Effect of relativistic reversal of the ponderomotive force (PF), reported earlier for a collinear configuration of electron and laser standing wave [A. E. Kaplan and A. L. Pokrovsky, Phys. Rev. Lett., 95, 053601 (2005)], is studied here theoretically for various types of polarizations of the laser beam. We demonstrated that the collinear configuration, in which the laser wave is linearly polarized with electric field $\stackrel{P\vec}{E}$ parallel to the initial electron momentum ${\stackrel{P\vec}{p}}_{0}$, is the optimal configuration for the relativistic reversal. In that case, the transverse PF reverses its direction when the incident momentum is ${p}_{0}=mc$. The reversal effect vanishes in the cases of circular and linear with $\stackrel{P\vec}{E}\ensuremath{\perp}{\stackrel{P\vec}{p}}_{0}$ polarizations. We have discovered, however, that the counter-rotating circularly polarized standing waves develop attraction and repulsion areas along the axis of laser, in the laser field whose intensity is homogeneous in that axis, i.e., has no field gradient.
Renal iron handling in the nephrotic syndrome

Renal iron handling in the nephrotic syndrome. Renal iron handling was characterized in three experimental models of the nephrotic syndrome: puromycin aminonucleoside, adriamycin and nephrotoxic serum. In adriamycin-induced nephrotic syndrome, which has previously been shown to result from alterations in pore size of the filtration barrier, the transferrin leak was most severe with a fractional clearance of 25%, a value identical to albumin. In contrast, in puromycin nephrotic syndrome and nephrotoxic serum nephritis the fractional clearance of transferrin was never greater than 2% and consistently less than the fractional clearance of albumin. The fact that iron/transferrin ratios in urine and serum were frequently different, sometimes higher other times lower, documents that iron and transferrin can be dissociated in tubule fluid and handled differently in regards to tubule uptake. Kidney iron concentration is also increased in both immunological and non-immunological forms of nephrotic syndrome. In the proximal tubule iron is present largely on the luminal aspect of the cell. In contrast, the major deposition of iron occurs in the lysosomes of the distal tubule cells. Kidney iron concentration does not correlate with tubule fluid iron content but can be prevented from increasing by systemic iron and/or transferrin depletion. This suggests that iron enters the distal tubule cells with transferrin via its receptors from the basolateral side of the distal tubule cells. In association with the increase tubule fluid and kidney iron, there is a marked reduction in kidney selenium and copper content. It is concluded that urinary iron and transferrin losses can vary greatly in different types of experimental renal diseases, and that iron and transferrin can be dissociated in the tubule fluid. The increase iron in association with the reduction of copper and selenium, presumably with their respective enzymes, could place the kidney at risk for injury from free radicals.
Women's Responses to Written Nutrition Messages

One hundred forty-three adult women voluntarily provided written responses to mes sages on the topics of weight control and vitamin supplements. These messages were written in two styles: those defined as “high human interest” were written in the first person and in a highly personal style; in contrast, “low human interest” messages presented the information in an equally readable format, but with less personal lan guage. After reading the message on weight control, the women recorded more thoughts which related to their own experiences with dieting and weight control. However, in response to the message about vitamin supplements, respondents wrote more questions or asked for clarification. The level of the respondent's nutrition knowledge was signifi cantly correlated with the total number of responses written after reading the vitamin supplement message and also with responses to the “high human interest” messages.
It gets better ... all in good time: messianic rhetoric and a political theology of social control

Working from Walter Benjamin’s “On the Concept of History,” this essay examines the recent interest in the messianic and messianicity in continental philosophy. To ground its discussion, the essay analyzes two recent cultural examples of messianic rhetoric – Barack Obama’s 2008 and 2012 presidential campaigns and Dan Savage’s 2010 It Gets Better Project, in order to explore hidden theological dimensions of recent cultural and political discourse in the US. The essay argues that both examples showcase a reliance on the language of the messianic promise as a means of creating a docile public focused on imagined future liberation rather than a critical confrontation of the often violent and disturbing realities of the now. At the same time that the essay problematizes messianic rhetoric’s connection to deeply entrenched narratives of “progress,” the essay also works to posit alternative visions of the messianic and to question whether it is possible to redefine the concept of messianism without relying on a ...
Trade, Pollution Transfers and Spillovers: Conditions for Welfare Outcomes

I use a model of indirect utility and compensated demand functions to analyze conditions for welfare effects when countries engage in trade involving a pollutant. The paper questions whether there is a transfer problem in such a trade and what conditions could set the stage for welfare effects. The results show that, countries’ (both trade partner’s and non-participants’) welfares increase not necessarily with distance from the pollution generating location (country) but with their marginal propensities to consume the good, substitutability in the good in question, the type of good (normal, Giffen and or inferior) and the spatial separability of the pollutant.
The Crucial Importance of Production and Operations Management

The history of the recent decline of production and operations management (POM) in academic importance is traced. POM's fundamental importance as a functional area is argued on the basis of four criteria: (I) centrality in organizations; (2) share of organizational resources; (3) pervasiveness in industrial society; and (4) significance in social change.
NDE of rivet holes in aging aircraft components using Lamb waves

This paper is concerned with the quantitative nondestructive evaluation of corrosion around and cracks emanating from rivet holes in typical aircraft structural components. Current techniques for detecting defects around rivet holes are time consuming and qualitative. A recently developed ultrasonic technique using plate guided Lamb waves as probes has been found to be successful in laboratory specimens and appear to have the potential to improve the speed and robustness of the inspection. The general features and future prospects of the method is described in the paper.
OA13.01. Mind-Body Medicine Skills training for self-care and emotional well-being in medical students

Purpose The purpose of this study was to examine the effect of a Mind-Body Medicine program for enhancing self-care and well-being among first year medical students. Depression and anxiety are common among medical students (West et al, 2011) and physicians (Krasner et al, 2009). Further, distress among medical students is associated with poor patient care (Dyrbye et al, 2010; Krasner et al, 2009). Thus, prevention and self-care have become central to medical education. One approach to developing self-care competencies among medical students is through enhancing mind-body skills. At the GUMC, these skills are taught in a Mind-Body Skills (MBMS) program. The 11week MBMS program includes teaching of self-awareness, relaxation, meditation, guided imagery, biofeedback, physical exercise, art, music and movement. The program promotes self-care within a context of group support.
Site-directed mutagenesis studies of rat steroid 5α-reductase (isozyme-1): mutation of residues in the cofactor binding and C-terminal regions

We have investigated the roles of highly conserved glycine (G175, G185), negatively charged (E188, D165) and histidine residues (H233, H237) in rat steroid 5alpha-reductase (isozyme-1), on NADPH, testosterone (T) binding and enzyme activity. The mutations G175R and G175S result in a two- to threefold increase in K(m)(NADPH) and an approximately fourfold decrease in the V(max) with no change in K(m)(T). The mutation G185W resulted in a fivefold decrease in K(m)(NADPH) and an eightfold decrease in V(max), with no change in K(m)(T), whereas the mutations E188Q and D165N both resulted in inactive enzyme. Steady-state kinetic measurements showed that the mutation H233R resulted in an approximately 40-fold decrease in V(max), an approximately 20-fold increase in K(m)(T) and no alteration in K(m)(NADPH), whereas the mutation H237R resulted in virtually inactive enzyme. The results suggest that the conserved glycines are not essential for cofactor binding and activity, and that the negatively charged residues may contribute to enzyme stability, whereas the C-terminal histidines appear to be involved in substrate binding and catalytic activity.
THE TASK AHEAD1

(1961). THE TASK AHEAD. Annals of the Association of American Geographers: Vol. 51, No. 4, pp. 345-356.
Facile preparation of carbapenem synthons via microwave-induced rapid reaction

Abstract A simplified and stereocontrolled synthesis of α-vinyl and α-alkyl β-lactams has been achieved in open vessels under microwave irradiation in unmodified domestic microwave ovens. These compounds - prepared in the course of a few minutes for each reaction step (including catalytic transfer hydrogenation) - are convenient synthons for various cis and trans carbapenems.
Methods of extinction risk assessment developed for US West Coast salmon

In assessing extinction risk for Pacific salmon (Oncorhynchus spp.), a variety of interacting risk factors are considered, some of which can be quantified but many of which are qualitative. In addition to the common measures of population abundance and trends for individual populations, these factors include ecological and genetic effects of hatchery fish, changes in life history traits, selective effects of harvest, trends in freshwater habitat condition, and climate variation. Combining such information into an assessment of the overall degree of risk facing populations and species relies heavily on scientific judgement rather than explicit quantitative criteria. To organize multifactor information and ensure consistency, a risk-matrix method has been implemented in which individual risk factors are scored on a 5-point scale, and then combined into an overall assessment of extinction risk.
Influence of Flexibility on the Fatigue Performance of the Base Plate Connection in High-Mast Lighting Towers

This study investigates the effect of base connection geometry on base plate flexibility and the fatigue performance of multisided high-mast lighting towers. Three parametric studies investigating the effect of base plate thickness, tube wall thickness, and anchor rod configuration are discussed in this paper. The results of this study show that of the geometric parameters considered, base plate thickness has the largest influence on the stresses in the tube wall adjacent to the weld toe. By increasing the base plate thickness of the tower, significant improvement to the fatigue life is observed because the maximum stress, and hence stress range, at the base plate-to-tube wall thickness is reduced due to a reduction in local bending in the tube wall.
XPD Helicase Speeds through a Molecular Traffic Jam

Helicases and other DNA translocases must travel along crowded substrates. In this issue, Honda et al. (2009) report that the archaeal XPD helicase can bypass a single-stranded DNA-binding protein without either molecule being ejected from the DNA.
The Influence of Marginal Buyers on Monopolistic Competition

Two extreme views of marginal buyers, 121.— Professor Hotelling's case, 122.— Professor Chamberlin fails to recognize their importance, 122.— Another view of the same situation, 123.— Effect on his conclusions, 126.— Another possibility under differentiation of product, 129.— A further stage: competitors still more numerous, 132.— Conclusions, 134.
COMMUNITY ECOLOGY AND THE GENETICS OF INTERACTING SPECIES

panding the synthesis of ecology and genetics. Ecology 84: 545-558. Odum, E. P. 1969. The strategy of ecosystem development. Science 164:262-270. Palumbi, S. R. 2001. Humans as the world's greatest evolutionary force. Science 293:1786-1790. Pimm, S. L. 1982. Food webs. Chapman and Hall, London, UK. Roughgarden, J. 2002. Evolution reduced to ecology: history of conflict and cooperation between disciplines. Ecological Society of America 2002 Annual Meeting Abstracts: 45. Sober, E. 1984. The nature of selection. MIT Press, Cambridge, Massachusetts, USA. Wade, M. J. 1978. A critical review of the models of group selection. Quarterly Review of Biology 53:101-104. Whitfield, J. 2002. Neutrality versus the niche. Nature 417: 480-481. Whitham, T G., W. P. Young, G. D. Martinsen, C. A. Gehring, J. A. Schweitzer, S. M. Shuster, G. M. Wimp, D. G. Fischer, J. K. Bailey, R. L. Lindroth, S. Woolbright, and C. R. Kuske. 2003. Community genetics: a consequence of the extended phenotype. Ecology 84:559-573. Wilbur, H. M. 1972. Competition, predation, and the structure of the Ambystoma-Rana sylvatica community. Ecology 53: 3-21. Williams, G. C. 1992. Natural selection: domains, levels, and challenges. Oxford University Press, Oxford, UK. Wilson, D. S. 1980. The natural selection of populations and communities. Benjamin/Cummings, Menlo Park, California, USA.
Will the Opacich Fieldwork Model Work

One of the dilemmas for occupational therapy fieldwork education is how to maintain and promote a holistic approach when our traditional model is a separatist one. Traditionally and historically, most Level II fieldwork education has been offered in 2- or 3-month experiences, with one affiliation being in a physical disabilities setting, another in a mental health setting, and a third, if chosen, in a pediatrics or specialty setting, although this arrangement has never been prescribed by AOTA. The shortage of psychosocial fieldwork sites and the increasing demands for efficacy have forced us to examine not only how we will meet the unrelenting need for sites but also how we will fulfill the expectations for effective and meaningful applied education for our students. Although health care delivery, and even health care reform, are reimbursement driven, we cannot abandon the humanistic and holistic values on which our profession was built. Reflection on our roots leads us to the importance of the inclusion of psychosocial considerations for every client. One way to accomplish this is to have sites that function within a medical model, where the primary focus is biological, include psychosocial issues in their treatment planning more overtly, just as sites whose primary focus is psychosocial need to become more overt about addressing clients' biological needs. A collaborative approach between academic and fieldwork educators would be necessary to provide training and support for affecting these changes. The fieldwork reconceptualization offered by Opacich is intriguing.(ABSTRACT TRUNCATED AT 250 WORDS)
Magnetotelluric observations in the western Ouachita Mountains, southeastern Oklahoma

The first magnetotelluric (MT) analysis of the Ouachita Mountains region is presented. Magnetotelluric data acquired at 19 sites along a 60-km profile in southeastern Oklahoma were used to image the western extension of the Ouachita Mountains and to determine the poorly known subsurface interaction between the Pennsylvanian Tishomingo‐Belton uplift and the subsurface extension of the exposed western Ouachita Mountains. Drill‐hole data, geologic mapping, seismic reflection profiles, and 1-D and 2-D MT-derived models indicate that lying beneath the low‐resistivity Gulf Coastal Plain sediments are 2–3 km of deep‐water lower Pennsylvanian (Jackfork Group) sediments and 6–8 km of Ouachita facies lithologies, mainly consisting of the Stanley Group. Beneath the profile’s northern section are 2–4 km of Atoka Formation sediments, probably deposited within the Arkoma basin, that underlie thrusted zones of the Stanley Group. The most unique feature is a high‐resistivity zone beneath stations 7–9, interpreted to be P...
Elastic interaction of two precipitates subjected to an applied stress field

Using the Born approximation to an integral equation, analytic approximations are obtained for the strain fields and interaction energies associated with two elastic inhomogeneities subjected to a uniformly applied stress field. Solutions are obtained for two spheres of unequal size and two rectangular parallelepipeds also of different dimensions in isotropic media for an applied tensile stress. The method employed can be extended to systems of more than two inhomogeneities and other precipitate morphologies.
Unsteady flows of a third-order viscoelastic fluid

Unsteady third-order viscoelastic flow is examined for the purpose of determining a method by which certain material constants in theRivlin-Ericksen theory can be measured. The concept of an intrinsic pressure hole error is used, and an expression for this error is derived for third-order flow. It is also shown that the velocity field for unsteady creeping motion of a third-order fluid is identical at any time to a corresponding steady third-order flow. The pressure field, however, depends upon the rate of change of the flow with time.
The Large Window Ductus: A Surgical Trap

A rare window type of patent ductus arteriosus is reported that was large (15 mm in maximal transverse dimension) but had virtually no length and hence was externally invisible. The smaller aortic isthmus (4 mm in diameter), which was intrapericardial, was mistaken for the ductus and was inadvertently clip-occluded, leading to death. After a specific diagnosis is made, the large window ductus should be patched on cardiopulmonary bypass with a transpulmonary approach.
Application of a theory of simulation to models of mobile communication systems (invited talk) (abstract only)

Computer simulation can be seen as a composition of local maps. This axiomatic treatment, known as Sequential Dynamical Systems (SDS), has been developed at Los Alamos over the last three years. The composed dynamics depend on the local maprs, their dependencies which are represented by a graph with the maps located at the vertices and edges indicating dependency, and the order of evaluation of the maps. The determination of the isomorphy of two such SDS is a central question. In fact, distributed computing environments can also be viewed as SDS. Thus, the mapping of one SDS into another isomorphic SDS is of importance to the idea of a valid representation on a computing architecture as well as to obtain a better understanding of what a computer simulation is.The detailed simulation of moving transceivers in large scale urban environments is possible using TRANSIMS, an applied transportation system simulation project also at Los Alamos. By projecting the locations onto a grid-like structure, and assigning local rebroadcast algorithms to those locations, we induce an SDS that directly represents the communication system at a point in time. The dynamics of the packet flows are consequently simulated by the SDS.The semantics of the SDS, in the sense of what the simulation is doing (routing, resource allocation, congestion control, etc) can be provided by analysis of the SDS in terms of its approximation of some algorithm.Some realistic examples of our approach to scalable simulation of mobile communication systems will be provided.
The effects of egg weight on subsequent broiler performance.

Abstract INTRODUCTION INVESTIGATIONS concerning the relationship of egg weight and subsequent performance of broilers to various ages have led to conflicting reports. O’Neil (1950), working with Barred Plymouth Rocks, concluded that those chicks hatching with the highest percentage of the original weight of the egg are heavier at eight weeks of age, more efficient in feed consumption and have a lower rate of mortality. Wiley (1950) likewise concluded that a positive trend in body weight and livability existed in favor of birds from large eggs. Although this trend was not statistically significant, he did find significant differences in feed conversion in favor of birds hatched from larger eggs. Any advantage in favor of birds from large eggs was usually overcome by twelve weeks of age as evidenced by the reduction in magnitude of the correlations between egg size and chick weight from 3–12 weeks of age. That chicks from large…
Too small to overlook

Voluntary reporting of nanomaterials by industry has failed. Mandatory measures are a step in the right direction, but the field needs more data sharing and oversight, say Andrew Maynard and David Rejeski.
Strong Trans Influence Methoxymethyl Ligand in B(12) Cobaloxime and Imine/Oxime Model Complexes: Structural, Spectroscopic, and Molecular Mechanics Investigations

The CH(2)OCH(3) ligand has a large trans influence comparable to that of bulky alkyl groups but lacks the complication of marked steric effects. However, crystals of model complexes with this ligand have proved difficult to obtain. The crystal structures of the cobaloximes reported here, Me(3)BzmCo(DH)(2)CH(2)OCH(3).0.6CH(3)OH (1) and 4-MepyCo(DH)(2)CH(2)OCH(3) (2) [DH = monoanion of dimethylglyoxime, Me(3)Bzm = 1,5,6-trimethylbenzimidazole, and 4-Mepy = 4-methylpyridine], triple the number of cobaloxime structures with CH(2)OCH(3). Also, these are the first structures in this class of models with an N-donor planar heterocyclic axial donor ligand, L. The planes of the Me(3)Bzm and 4-Mepy ligands are almost perpendicular to the respective planes of the four equatorial DH nitrogen donors and bisect the (O(-))N-Co-N(OH) angles. The Co-N(L) bond distances average 2.096(2) A, confirming the strong trans influence of CH(2)OCH(3). Geometry optimization via molecular mechanics using MacroModel 5.0 and an AMBER-type force field was applied to both cobaloxime-type and imine/oxime-type B(12) models. In our initial work with some imine/oxime models, the calculated structures did not compare well to the solid-state structures. Therefore, adjustments to the force field were evaluated. The major adjustment that improved the fit of the computed and experimental structures was an approximately 10% reduction of the van der Waals (vdw) parameters for both the N donors and the C(sp(2)) atoms linked to the N donors; this adjustment may reflect the electron-withdrawing effect of the metal center. Analysis of (1)H-(13)C coupling constants of Me(3)Bzm lends support to the concept that the atoms in the ligands were modified, but only slightly, by the metal center. To reproduce the dependence of geometric features on the trans influence, different force field parameters for L-Co bonds were used for compounds with weak (Cl) and those with strong (CH(2)OCH(3)) trans influence ligands. These small modifications allowed us to model the structural features of both classes of models well.
Gas-Liquid Chromatographic Deterpmination of 2- (O-Chlorophenyl) -2- (P-Chlorophenyl)-Acetic Acid in Biological Fluids

AbstractA gas-liquid chromatographic method for the determination of 2-(o-chlorophenyl)-2-(p-chlorophenyl)-acetic acid in human blood and urine has been developed. The procedure is based on ether extraction of acidified whole blood or urine, derivatization with boron trifluoride-methanol, and GLC analvsia. This method can detect 0.1 uq/ml of compound in blood. Analysis of blood and urine from human volunteers indicated that the procedure is suitabla for pharmacokinetics studies and clinical monitoring of patients.
Nanoscale energy storage materials produced by hydrogen-driven metallurgical reactions

Nanoscale energy storage materials offer enhanced kinetics, material stability and gravimetric capacity, with respect to their bulk counterparts. Hydrogen-driven metallurgical reactions (HDMR) represent a novel method for synthesis of these nanomaterials. Nanoscale and nanocomposite electrodes for Li-ion batteries synthesized by HDMR demonstrate reversible lithium cycling at low temperature (298 °C). The nanocomposite electrodes are composed of an electrochemically active species (Li-Sn, Li-Al-Sn and Li-Al-Si) imbedded within an inert Li 2 O matrix. These electrodes are prepared in the charged state and therefore do not suffer from the first cycle capacity loss that is characteristic of the intermetallic anodes. This novel synthesis technique may also be applied to the preparation of new hydrogen storage compounds.
Critical issues in applications of self-assembled monolayers

Abstract Molecular self-assembly of supported monolayers can produce a variety of structures with different types of surface functional groups and with varied topography. Such structural flexibility promises many applications. In addition, strategies for precision chemical patterning have evolved which expand the possibilities. Real applications of these monolayers will require precise control of structural features which in turn depends critically upon improved understanding of such factors as formation mechanisms and mixed composition phase stability. Recent advances show that such an understanding should evolve in the future.
High Definition in Minimally Invasive Surgery: A Review of Methods for Recording, Editing, and Distributing Video

The use of high-definition cameras and monitors during minimally invasive procedures can provide the surgeon and operating team with more than twice the resolution of standard definition systems. Although this dramatic improvement in visualization offers numerous advantages, the adoption of high definition cameras in the operating room can be challenging because new recording equipment must be purchased, and several new technologies are required to edit and distribute video. The purpose of this review article is to provide an overview of the popular methods for recording, editing, and distributing high-definition video. This article discusses the essential technical concepts of high-definition video, reviews the different kinds of equipment and methods most often used for recording, and describes several options for video distribution.
Combining the best of bulk and surface micromachining using Si (111) substrates

This process combines the best features of bulk and surface micromachining. It enables the production of stress free, thick, virtually arbitrarily shaped structures with well defined, thick or thin sacrificial layers, high sacrificial layer selectivity and large undercuts using IC compatible, processes. The basis of this approach is the use of readily available {111} oriented substrates, anisotropic Si trench etching, SiN masking and KOH etching.