cssi/SciSciGPT-SciSciNet huggingface dataset:
Optimal agent cooperation with local information

Multi-agent systems are in general believed to be more efficient, robust, and versatile than their single-agent equivalents. However, it is not an easy task to design strategies that fully exploit the multi-agent benefits, and with this in mind we address several multi-agent system design issues. Specifically, it is of central importance to determine the optimal agent group composition, which involves a trade-off between the cost and performance increase per additional agent. Further, truly autonomous agents solely rely on on-board environment measurements, the design of which requires quantifying the multi-agent performance as a function of the locally observed environment areas. In this thesis, we focus on the collaborative search for individually rewarding resources, i.e. it is possible for multiple agents to incur the same reward. The system objective is to maximize the aggregate rewards incurred. Motivated by a cooperative surveillance context, we formulate a graph traversal problem on an unbounded structured graph, and restrain the agent motion spatially so that only the lateral agent separation is controlled. We model the problem mathematically as a discrete, infinite state, infinite horizon Dynamic Program and convert it using standard techniques to an equivalent Linear Program (LP) with infinitely many constraints. The graph spatial invariance allows to decompose the LP into a set of infinitely many coupled LPs, each with finitely many constraints. We establish that the unique bounded function that simultaneously satisfies the latter LPs is the problem optimal value function. Based on this, we compute the two-agent optimal value function explicitly as the solution of an LP with finitely many constraints for small agent separations, and implicitly in the form of a recursion for large agent separations, satisfying adequate connection constraints. Finally, we propose a similar method to compute the state probability distribution in steady state under an optimal policy, summarizing the agent behavior at large separations in a set of connection constraints, which is sufficient to compute the probability distribution at small separations. We analyze and compare the optimal performance of various problem instances. We confirm and quantify the intuition that the performance increases with the group size. Some results stand out: for cone-shaped local observation, two agents incur 25% less cost than a single agent in a mine field type environment (scarce though high costs); further, for some environment specifics, a third agent provides little to no performance increase. Then, we compare various local observation zones, and quantify their effect on the overall group performance. Finally, we study the agent spatial distribution under an optimal policy, and observe that as rewards are scarcer, the agents tend to spread in order to gather information on a larger environment part. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)
Biologically inspired grasp primitives for a dexterous robotic hand to catch and lift a sphere

Joint motion profiles from nine human test subjects were recorded while catching and lifting a sphere. Significant differences between the two tasks presented themselves consistently across all test subjects. In general, larger abductions and hyperextensions of the metacarpophalangeal joints were observed. The joint motions of the test subjects were simulated in Simulink with a skeletal structure of the human hand. From the recorded motions, cubic polynomials were fit to the joint angle data to form two distinct grasp primitives. Simulations of these primitives were performed in Simulink with a skeletal structure of the Shadow Hand. These primitives were subsequently used on the physical system by a human operator who was able to pick up and catch a sphere with the Shadow Hand. An electromyogram signal measured from the forearm of the test subject was used as the input to the Shadow Hand controller. The sphere was successfully caught on five out of seven attempts with no prior practice with the system. The sphere was successfully lifted in seven of twelve attempts.
The Principles and Practice of International Commercial Arbitration: IBA Rules of Ethics for International Arbitrators (1987)

Reprinted with permission of the International Bar Association, London. © International Bar Association, 1987 INTRODUCTORY NOTE International arbitrators should be impartial, independent, competent, diligent and discreet. These rules seek to establish the manner in which these abstract qualities may be assessed in practice. Rather than rigid rules, they reflect internationally acceptable guidelines developed by practising lawyers from all continents. They will attain their objectives only if they are applied in good faith. The rules cannot be directly binding either on arbitrators, or on the parties themselves, unless they are adopted by agreement. Whilst the International Bar Association hopes that they will be taken into account in the context of challenges to arbitrators, it is emphasised that these guidelines are not intended to create grounds for the setting aside of awards by national courts. If parties wish to adopt the rules they may add the following to their arbitration clause or arbitration agreement: “The parties agree that the rules of Ethics for International Arbitrators established by the International Bar Association, in force at the date of the commencement of any arbitration under this clause, shall be applicable to the arbitrators appointed in respect of such arbitration.” The International Bar Association takes the position that (whatever may be the case in domestic arbitration) international arbitrators should in principle be granted immunity from suit under national laws, except in extreme cases of wilful or reckless disregard of their legal obligations.
Abstract 15737: Xenon Delivery Into Subarachnoid Hemorrhage via Echogenic Liposomes Provides Long-Term Neuroprotection

Background: Consequences of subarachnoid hemorrhage (SAH) including intracerebral bleeding and vasospasm result in permanent neurologic dysfunction or death. We have developed Xenon-containing echogenic liposomes (Xe-ELIP) and have demonstrated early cellular neuroprotection. We hypothesize that stabilizing cells in the neurovascular unit in the early stages of SAH provides long-term neurovascular benefit. Methods: Xe-ELIP were prepared by a pressurization-freeze method. Sprague Dawley rats (n=90) were evaluated: sham, SAH with no treatment, and following SAH ELIP only @30 minutes, Xe-ELIP @30 minutes, ELIP only @2 hours, Xe-ELIP @2 hours, and Xe-ELIP in multiple doses. SAH was induced by an endovascular perforation method. All treatments were administrated intravenously for 5 minutes in combination with ultrasound application over the common carotid artery to trigger Xe release from the circulating Xe-ELIP. Xe concentration in the carotid arteries was measured using gas chromatography-mass spectroscopy (...
On Stable Bundles of Ranks 2 and 3 on P^3

We study rank 3 stable bundles E on P^3 as extensions of a line bundle B on a smooth surface S in P^3 by the direct sum of three copies of O_{P^3}(-\nu). In most cases, S (the dependency locus of three sections of E(\nu)) lies in the Noether-Lefschetz locus. We give a detailed analysis when S contains a line L and B is constructed from divisors of the form aL+bC for H=L+C a hyperplane section of S. We study the parameter space of this construction and compare it to the full (Gieseker-Maruyama) moduli space. We also analyse the case when B is a power of the hyperplane bundle. The same approach is used to study rank 2 bundles on P^3.
Low carnitine intake and altered lipid metabolism in infants

We examined the effect of dietary carnitine on variables of lipid metabolism in human infants. Normal male full-term infants were fed an isolated soy-protein-based formula with or without added carnitine from age 6-9 d to age 112 d. Growth and food intake were measured throughout the study. At ages 56 and 112 d serum concentrations of carnitine, free fatty acids, and triglycerides and urinary excretion of carnitine and medium-chain dicarboxylic acids were measured. Serum carnitine concentrations were lower in all infants fed unsupplemented formula. There was no difference in growth or food intake between the two groups of infants. Serum free fatty acid concentrations were significantly higher in the infants not receiving dietary carnitine. Moreover, excretion of all three medium-chain dicarboxylic acids was significantly higher in infants not receiving dietary carnitine. We conclude that lack of dietary carnitine affects lipid metabolism of infants during the first 4 mo of life.
Zinc status of highly trained women runners and untrained women.

Endurance training effects on zinc status were assessed by comparing 13 highly trained (HT) and 10 untrained (UT) women. Blood and 24-h urine samples before and after a 25-mg oral Zn load, and 3-d dietary records were evaluated. Mean daily Zn intakes did not differ and were below the Recommended Dietary Allowances for both groups. Fasting concentrations of plasma Zn, serum albumin, alpha 2-macroglobulin, and erythrocyte Zn content did not differ. However, HT women had significantly (p less than 0.05) higher urinary Zn excretion (HT: 6.7 +/- 0.8 and UT: 4.5 +/- 0.7 mumol/d) and reduced responses to the oral Zn than did UT in terms of maximal responses (HT: 11.0 +/- 1.6 and UT: 16.2 +/- 1.2 mumol/L) and areas under the curve (HT: 34.8 +/- 2.7 and UT: 43.6 +/- 2.7 mumol.L-1.4h-1). The greater urinary Zn excretion by HT women may reflect higher rates of skeletal muscle turnover. Whether their reduced responses to the Zn load reflect differences in plasma volume, entry or removal of plasma Zn, or absorption is unknown.
Evaluation of Naturally‐Occurring Organisms as Food for Juvenile Crayfish Procambarus clarkii1

Nutritionally important food items for crayfish have been difficult to identify and little information exists for third instar (first-feeding) crayfish. In this study, three major groups of potentially-important foods were fed to communally-reared third instar crayfish (Procambarus clarkii) and weight gain and survival were measured over a 30 day period. Mean weight gain (% increase) of crayfish fed the zooplankton Daphnia magna alone or in combination with other food items, ranged 2, 277–3, 239%, while mean weight gain of crayfish fed unidentified aquatic bacteria, the aquatic macrophyte Myriophyllum spicatus, combinations of bacteria and plant, or a negative control ranged 254–767%. No significant interaction of food items was detected. Bacteria appear to be a utilizable nutritional source for juvenile crayfish, but, using the methods employed in this study, do not support maximum rates of weight gain. Thus, pond management strategies that maximize zooplankton populations at the time of crayfish hatching might be beneficial.
Hybridization of Desmodium species

Under different light regimes, Desmodium canum(Gmel.) Schin. & Thell. responded as a long-day plant, D. intortum(Mill.) Urb. and D. uncinatum(Jacq.) dc. as short-day plants, and D. sandwicense E. Mey. as photoperiod-insensitive. Tripping method with anther removal, washing of stigmas and pollen transfer was simple and less time-consuming, gave an equal number of hybrids but more selfed progenies than the tedious method of emasculating prior to anthesis. A high percentage of selfing indicated that the four species are self-compatable and that foreign pollen did not show advantage over that from the same plant. Silver marking of the leaflet midrib of D. sandwicense and D. uncinatum in crosses with D. intortum was a useful dominant marker, but did not appear in the cross D. canum × D. uncinatum. Brown flecking of D. intortum leaflet was a dominant characteristic and occurred on the progenies from crosses with D. sandwicense and D. uncinatum along with the silver marking. Stem growth habit, leaflet form, and pubescence were helpful but less reliable for identifying hybrids. F1 hybrids were readily verified by isozyme patterns of esterase and peroxidase, the zymograms having common and different bands of the parents.
Review: In stable obstructive CAD, PCI plus medical therapy (MT) does not differ from MT alone

Source Citation Stergiopoulos K, Boden WE, Hartigan P, et al. Percutaneous coronary intervention outcomes in patients with stable obstructive coronary artery disease and myocardial ischemia: a coll...
Multiple unloadings by nectar foragers in honey bees: a matter of information improvement or crop fullness?

When a honey bee forager returns to her hive and unloads nectar, she sometimes transfers her entire load to one bee, but other times she makes a series of unloadings to several bees. One intriguing hypothesis for why foragers make multiple unloadings is the Information Improvement hypothesis: multiple unloadings improve a forager’s estimate of the difficulty in finding a receiver bee, and thus of the allocation of labor between nectar collecting and nectar processing. In this paper, we discuss a possible weakness in the empirical evidence in support of the Information Improvement hypothesis. We also present a competing hypothesis, the Crop Fullness hypothesis: multiple unloadings arise from a mismatch between the amount of nectar a forager has to unload and the amount of nectar a receiver can imbibe. Finally, we test the two hypotheses by checking their predictions regarding the conditions under which multiple unloadings occur and which bee (forager or receiver) breaks off the first unloading when a forager makes multiple unloadings. We find that multiple unloadings are common only at times of high nectar influx and that most often it is the receiver, not the forager, who breaks off the first unloading. We argue that both of these findings are contradictory to the Information Improvement hypothesis but are consistent with the Crop Fullness hypothesis. Furthermore, we relate our findings to a recent theoretical study (Gregson et al., 2003) which shows, by means of a simulation model, that the level of multiple unloadings observed can be accounted for by a mismatch between the crop loads of foragers and the crop capacities of receiver bees. We combine our measurements with the Gregson et al. model to identify the rule used by receiver bees in deciding when to stop receiving more nectar. We conclude that receivers make this decision during the course of an unloading, not after completing an unloading. Finally, with this conclusion in hand, we test the Gregson et al. model by comparing predictions and observations on how full receivers are when they decide to break off an unloading. We find a remarkable agreement (prediction: 60%, observation: 52–59%), in strong support of the model.
Fluvial responses to environmental perturbations in the Northern Mediterranean since the Last Glacial Maximum

Abstract The numerical model HydroTrend, that produces daily time series of water discharge and sediment load to the ocean, is applied to three Mediterranean drainage basins to: (i) simulate the water and sediment flux changes to sedimentary basins through time and (ii) determine the impact of potential forcing factors on sediment and water fluxes to sedimentary basins and how this impact varied through time. Climate (precipitation, temperature and glacier equilibrium line) and drainage basin (basin elevation, drainage area and reservoir) reconstructions of the Po, Rhone and Tet river basins over the last 21 000 Cal. years B.P. are used as input to the model. Simulated sediment fluxes at the river mouth for the Po, Rhone and Tet River systems during the late Pleistocene were considerably higher compared to Holocene pristine sediment flux, with a factor 3.5, 2.4 and 2.4 respectively. For the Po River system and the Rhone River, deglaciation in the late Pleistocene is the main factor, responsible for these higher sediment fluxes. Drainage basin area change due to sea-level rise is the main cause of decrease in sediment flux for the Tet River system and to a certain extent for the Po River system. Man-made reservoirs reduced sediment flux to the ocean for the Po, Rhone and Tet rivers over the last 3–6 decades with a factor of 1.3, 3.8 and 2.4 respectively. Fluvial responses to climate and basin variations are reflected in the peak flood discharge and sediment concentration curves, where present-day water peak flood curves for all three rivers are the highest in the last 21 000 Cal. years B.P. However, their associated sediment concentration curves show opposite results because of diminishing glacial area and the impact of reservoirs. The Tet River system has the ability to generate hyperpycnal plumes although the occurrence frequency changes over time. Prior to 15 500 Cal. years B.P. the river system area was extended due to the low sea level, causing a less favorable regime to generate hyperpycnal events. Presently sediment trapping due to man-made reservoirs alters the river ability to generate hyperpycnal events.
Stepfathers and Stepfamily Education

Although stepfamily education is believed to improve family relationships, little is known about how stepfamily education impacts stepfather relationships specifically. Using a systems theory approach, this qualitative study examines the experiences of 14 European American stepfathers who participated in a 12-hour research-based stepfamily education course. Although the majority of men initially needed some encouragement to attend, they all felt the experience was worthwhile. Participants discussed their motivation for attendance, as well as the perceived benefits of taking the course including increased family bonding, relationship skill development, and enhanced fathering practices. The findings support ongoing efforts to help stepfathers be successful in their roles and relationships with their stepchildren. Implications for practice and recommendations for engaging stepfathers are provided.
A comparison of open architecture standards for the development of complex military systems: GRA, FACE, SCA NeXT (4.0)

Tightly coupled, poorly encapsulated, hardware and software implementations have resulted in systems that are rigid and fragile. These systems lack desirable architectural attributes including efficient extensibility, technology insertion, hardware and software portability, and effective use of Commercial Off The Shelf (COTS) equipment. The realization of flexible and robust systems without a supporting architecture is difficult, requires significant system rework, and precludes the concept of a product line. Three recently generated examples of standards intended to mitigate these fundamental engineering shortcomings are the Software Communications Architecture (SCA) promoted by the Joint Tactical Radio System (JTRS) Joint Program Engineering Office (JPEO), the Government Reference Architecture (GRA) promoted by ARMY CERDEC, and the Future Avionics Capability Environment (FACE) promoted by The Open Group and sponsored by NAVAIR. In this paper we compare these three architectural standards relative to the concerns identified in each and the techniques proposed. We find that these three approaches promote similar key concerns and use similar techniques to achieve a loosely coupled, modular architecture that allows the realization of flexible and robust systems.
Omega-3 Polyunsaturated Fatty Acids: A Potential New Treatment of Immune Renal Disease

Omega-3 polyunsaturated fatty acids are among new treatments being tested for efficacy in immune renal disease. The principal omega-3 polyunsaturated fatty acids are eicosapentaenoic acid and docosahexaenoic acid. They are derived from alpha-linolenic acid, which is found mainly in marine lipids. Eicosapentaenoic acid and docosahexaenoic acid undergo biologic transformation into trienoic eicosanoids that alter inflammatory mediators and vascular reactivity, both of which are important in the pathogenesis of certain glomerular immune diseases. Investigators have shown that proteinuria was prevented and survival was prolonged in autoimmune models of nephritis after dietary supplementation with fish oil. Furthermore, vascular damage may be modified by the influence of eicosapentaenoic acid and docosahexaenoic acid on blood rheology, aggregation of platelets, and plasma lipids. In short-term clinical studies, omega-3 polyunsaturated fatty acids seem to diminish cyclosporine-induced nephrotoxicity and the attendant complication of hypertension, to inhibit inflammatory and atherogenic mechanisms in lupus nephritis, and to preserve renal function and reduce proteinuria in IgA nephropathy. Long-term clinical trials for testing fish oil in these three clinical conditions are under way to confirm or refute these apparent beneficial therapeutic results.
Current Opinions on Medical Radiation: A Survey of Oncologists Regarding Radiation Exposure and Dose Reduction in Oncology Patients

Purpose The aim of this study was to evaluate oncologists' opinions about the use of ionizing radiation in medical imaging of oncology patients. Methods An electronic survey was e-mailed to 2,725 oncologists at the top 50 National Cancer Institute–funded cancer centers. The survey focused on opinions on CT dose reduction in oncology patients and current philosophies behind long-term imaging in these patients. Results The response rate was 15% (415 of 2,725). Eighty-two percent of respondents stated that their patients or families have expressed anxiety regarding radiation dose from medical imaging. Although fewer than half of oncologists (48%) did not know whether CT dose reduction techniques were used at their institutions, only 25% were concerned that small lesions may be missed with low-dose CT techniques. The majority of oncologists (63%) follow National Comprehensive Cancer Network guidelines for imaging follow-up, while the remainder follow other national guidelines such as those of the Children's Oncology Group, the American Society of Clinical Oncology, or clinical trials. Ninety percent of respondents believe that long-term surveillance in oncology patients is warranted, particularly in patients with breast cancer, melanoma, sarcoma, and pediatric malignancies. The majority of oncologists would consider the use of low-dose CT imaging in specific patient populations: (1) children and young women, (2) those with malignancies that do not routinely metastasize to the liver, and (3) patients undergoing surveillance imaging. Conclusions Cumulative radiation exposure is a concern for patients and oncologists. Among oncologists, there is support for long-term imaging surveillance despite lack of national guidelines.
Institutions and the stabilization of party systems in the new democracies of Central and Eastern Europe

Most explanations of party system stability focus on the strength of mass-elite linkages. We highlight the role of institutions, focusing on how electoral rules and elected institutions, especially the presidency, impact elites' incentives to coordinate on a stable set of parties or to form new parties, thus affecting electoral volatility. Using Central and Eastern European elections data, we find that directly elected presidents increase volatility and that presidential power magnifies this effect. Absent a directly elected president, high district magnitude is associated with increased volatility, but district magnitude dampens the impact of an elected president on volatility; hence, our findings underscore the interactive impact of institutions on party systems. We also find evidence that bicameralism and concurrence of presidential and parliamentary elections decrease electoral volatility. Our model not only explains persistently high electoral volatility in Eastern Europe, but the extreme stability of Western European party systems.
The Triumph of Agency over Structure: Shimon Peres and the Israeli Nuclear Program

This article advances the proposition that when the negotiator is empowered to reach an agreement on behalf of his or her government, agency has the potential to triumph over structure. The negotiator whose personal attributes include flexibility, sensitivity, inventiveness, tenacity and patience is more likely to meet this potential. Shimon Peres, the director-general of Israel’s Ministry of Defense in the mid-1950s, possessed many of these traits. He was also given virtually free rein by Prime Minister and Defense Minister David Ben-Gurion to pursue negotiations with France over the acquisition of a nuclear reactor. Despite significant structural hurdles – financial difficulties, domestic opposition, u.s. disapproval, and an unstable and divided French Fourth Republic – Peres’s unorthodox diplomacy allowed Israel to become a nuclear power. This case highlights the oft-overlooked role of agency in political science, in general, and in international negotiations, in particular.
The Differential Relationship Between Parental Worry and Adolescent Outcomes by Linguistic Preference Among Low-Income Mexican American Families

This study examined the moderating effects of parents’ linguistic preference, as a proxy for acculturation, on the relationship between parental worry and problem behaviors among 130 Mexican American early adolescents (M age = 13; 51 % male) living in public housing neighborhoods in the Southwestern United States. Based on the family stress model we hypothesized that adolescents whose parents reported more general worry would have higher rates of delinquency and substance use and those who reported higher levels of parental supervision would have lower rates of delinquency and substance use. We hypothesized that these relationships would differ by linguistic preference, with Spanish language being equated to less acculturation and more risky. Hierarchal linear models controlling for multiple children in the same family indicated that worry among parents predicted higher rates of delinquency and substance use for adolescents whose parents were more acculturated whereas no relationship was found for less acculturated parents. No support was found for the protective effect of parental supervision and parental worry did not predict levels of supervision. These findings suggest that global worry among parents may impact delinquency and substance use among adolescents in families with parents who prefer Spanish through pathways other than supervision. The protective effect of Spanish language preference, which may indicate lower parental acculturation among Mexican American youth, indicates the need for more research examining possible mediators of the relationship between living in high-risk environments such as public housing and adolescent delinquency and substance use in this population.
Comparison of Summarized Sires and Sampling Sires in Artificial Insemination. 1. Production and Reproduction

Abstract A breeding project was initiated in 19 state-owned Holstein herds in Pennsylvania to determine the differences in reproduction and production traits between daughters of summarized sires and sampling sires available from AI organization. Each herd was divided randomly into two groups; females in one group were bred to summarized sires, and females in the other group were bred to sampling sues. First service conception rates were similar for the two groups of sires (46.3% for summarized and 45.6% for sampling sires). Services needed to produce a milking daughter averaged 6.65. There were no significant differences between the two groups of females for any of the reproductive or management factors studied. Although not significantly different, lactational yields tended to be higher for daughters of summarized versus sampling sires. The summarized sires used in the project were of higher transmitting ability for production traits than the average of summarized AI sires and the sampling sires were about average of all sampling sires at the time of use. Breeding group differences in first generation daughter yields were similar to sire transmitting ability differences.
Functional interrelationships between follicles greater than 4 mm and the follicle-stimulating hormone surge in heifers.

The interrelationships between the FSH surge that initiates a follicular wave and the follicles in the wave were examined in heifers. In experiment 1, - 5-mm follicles were ablated 5 days after ovulation and heifers (n = 6/group) received a total dosage of 0, 37.5, 75, or 150 units of porcine FSH. Half of the FSH dosage was administered 24 h after ablation followed by the other half 12 h later. Blood samples were taken after the initial FSH injection for FSH assay, and ovaries were examined daily with ultrasound to monitor follicle growth. There were progressively higher FSH concentrations at the mean peak (8 h after initial injection in all groups) as the dosage increased (interaction of dose and time; p < 0.001). Compared to values in controls, the highest dosage (150 units) approximately doubled the number of 5- and 6-mm follicles; this then progressed into a 4to 7-fold increase in the number of 7- and 8-mm follicles. In experiment 2, either all (controls; n = 6), two (n = 11), one (n = 6), or zero (n = 6) follicles of the first wave of an estrous cycle were retained and the remaining were ablated upon reaching 5 mm. Scanning and blood sampling were performed every 8 h for 72 h after the initial ablation. Mean FSH concentrations during 0 to 72 h decreased (p < 0.004) as the number of retained follicles increased. In heifers in the onefollicle group, the randomly chosen 5-mm follicle developed the characteristics of a dominant follicle. The following conclusions were made: 1) the number of follicles that advanced into a follicular wave was increased by exaggerating the height of the FSH surge, 2) all 5-mm follicles of a wave contributed to the declining portion of the FSH surge, and 3) any 5-mm follicles at the emergence of a wave were capable of becoming the dominant follicle.
Electronic structure of rhodium

Local-density, all-electron, self-consistent energy-band calculations are reported for face-centered-cubic rhodium. The Fermi surface is obtained; charge form factors, the Compton profile, and the optical conductivity are determined. Results are compared with other calculations and with experiment where these exist. A possible ferromagnetic state is found for an increased lattice constant with a moment developing at about a=8.17 a.u.
Differences in rRNA metabolism of primary and SV40-transformed human fibroblasts

Abstract rRNA metabolism was compared in primary human diploid fibroblasts (WI-38) and in SV40-transformed cultures derived from WI-38 (VA-13 and SV-C52). Both in actively growing and nondividing diploid fibroblasts, mature rRNA, labeled with 3 Huridine or 3 H-methyl-methionine, decayed with a half-life of 72 ± 4 hr. In contrast, in growing SV40-transformed cells, as in HeLa and other established lines, rRNA was stable, and only began to show a half-life shorter than 700 hr as the cells reached maximum density. To determine the relative importance of degradation and synthesis in maintaining the cellular content of rRNA, the net synthesis of rRNA was evaluated by measurements of the transcription, processing and wastage of pre-rRNA. Accumulation of 3 H-methyl-methionine into precursors and mature rRNA was quantitated by an established computer program (Wolf and Schlessinger, 1977). The relative synthetic rates of 45S pre-rRNA increased by 50% or less in the transformed cells. In all cases, the rates of processing were identical and little if any nuclear wastage was observed: all of the 45S pre-rRNA gave rise to mature 28S and 18S rRNA. In growing normal cells, the net level of RNA could therefore be accounted for by the balance of the transcription of 45S pre-rRNA and cytoplasmic decay of 18S and 28S rRNA. In growing transformed cells, 18S and 28S rRNA were stable, and hence the net formation of rRNA was determined only by the rate of synthesis. This qualitative difference could give transformed cells a selective advantage.
Computing indicators of creativity

Divergent thinking has been linked to creative processes leading to innovative artifacts. Measuring creative divergence can be difficult. Across the USA, the Scalable Game Design (SGD) Project includes thousands of student participants building their own games through learning computational thinking (CT). To evaluate these games, a technique, the Computational Thinking Pattern Analysis (CTPA) [1], was developed, refined and used successfully. Under three different learning conditions, divergence was computed through CTPA, and then analyzed and explored as an indication of creativity.
An algebraic theory of multi-product decisions

We exploit the existence of matrix group symmetries on a production possibility set to identify group symmetries on the profit function. The groups are isomorphic, and provide a pre-ordering on firm preferences over prices. Together with additional structure on the technology, symmetries generate comparative statics on price responses. Linear and other invariances place bounds on firm choice vectors. Reflection group asymmetries on the feasible choice set also support welfare rankings over prices. The methods are adapted to study consumer decisions.
A modular framework for the analysis and optimization of power generation systems with CCS

Abstract A significant number of efforts are underway to develop and assess technologies that will lead to technically and economically viable routes to reduce the CO 2 emissions of fossil energy systems, particularly coal-fired power plants. Developing technologies to reduce emissions from these sources is essential for controlling atmospheric levels of CO 2 because of the widespread reliance on coal as an inexpensive and abundant energy source. Two major systems-level design challenges exist. The first is how to design new plants that incorporate CCS technology. The second is how to retrofit existing plants to capture CO 2 . Both design challenges can benefit from an optimization approach, which considers the application of multiple potential technologies and analyzes ways in which the whole plant-wide system can be integrated to increase overall efficiency. This paper will present a modular framework for the analysis and optimization of power generation systems with CCS that helps to meet these design challenges. In order to more completely understand the economic and operational tradeoffs associated with the various potential carbon capture technologies, and how they can be applied to new and existing plants, a unified, systemic framework has been developed to provide a common basis for evaluation. Given the complexity of the design problem and the fact that new technologies are continually being developed, this framework is modular in nature and incorporates algorithms for the selection, integration and optimization of carbon capture technologies for both new and existing plants. In addition to the framework itself, this paper discusses simulation modules representing various capture technologies and power plant components. The framework provides the means to link the various modules together in order to provide a holistic, systems perspective of plant wide operations. Results of analyses and optimization scenarios performed with the framework are also presented.
Removal of large fragments of the extensor process of the distal phalanx via arthrotomy in horses: 14 cases (1992-1998).

Objective—To evaluate the outcome of horses with large fragments of the extensor process of the distal phalanx that were removed by use of arthrotomy. Design—Retrospective study. Animals—14 horses with large fragments of the extensor process of the distal phalanx. Procedure—Medical records for horses with large fragments of the extensor process that were removed by use of arthrotomy were reviewed. Data retrieved from medical records included signalment, use of horse, affected limb, lameness history, lameness examination findings, radiographic findings, surgical technique, and outcome. Follow-up evaluation was obtained by telephone interview. Results—Most affected horses were < 5 years old and had a history of chronic lameness. Lameness grade ranged from 1/5 to 4/5. Fragments involved 20 to 45% of the dorsopalmar articular surface of the distal phalanx. Eight of 14 horses had a successful outcome. Outcome was not associated with age, duration or severity of lameness, or fragment size. Conclusions and Clini...
Approximate structured singular value computation via Frobenius norms

Two algorithms are presented to aid in the approximation of the structured singular value through minimization of the Frobenius norm. The first algorithm allows the uncertain terms to be complex. The second algorithm considers only real variations for real uncertain terms. An example problem is included, and advantages and disadvantages are discussed. >
Sequence and functional relationships between androgen-binding protein/sex hormone-binding globulin and its homologs protein S, Gas6, laminin, and agrin.

Abstract Androgen-binding protein/sex hormone-binding globulin ( ABP SHBG ) is an extracellular binding protein that regulates the bioavailability of sex steroids. ABP SHBG is closely related to the globular (G) domain of vitamin K-dependent protein S family of proteins and more distantly related to the G domains of several extracellular matrix proteins. ABP SHBG appears to have evolved from the fusion of two ancestral G domains. Expanding evidence suggests that ABP SHBG has other functions that are mediated through membrane binding, including signal transduction; however, the types of binding proteins (receptors) have not been identified. Sequence comparisons of ABP SHBG with G domains of its homologs protein S, Gas6, laminin, and agrin have identified regions of ABP SHBG that may bind receptors related to homolog receptors. These membrane receptors include β-integrins, α-dystroglycan, and receptor tyrosine kinases. The G domains of laminin and related proteins have clearly evolved from a common ancestor to interact with specific receptors and binding proteins. It remains to be determined if ABP SHBG followed this evolutionary pathway.
Oxidative stress accumulates in adipose tissue during aging and inhibits adipogenesis.

Aging constitutes a major independent risk factor for the development of type 2 diabetes and is accompanied by insulin resistance and adipose tissue dysfunction. One of the most important factors implicitly linked to aging and age-related chronic diseases is the accumulation of oxidative stress. However, the effect of increased oxidative stress on adipose tissue biology remains elusive. In this study, we demonstrate that aging in mice results in a loss of fat mass and the accumulation of oxidative stress in adipose tissue. In vitro, increased oxidative stress through glutathione depletion inhibits preadipocyte differentiation. This inhibition of adipogenesis is at least in part the result of reduced cell proliferation and an inhibition of G1→S-phase transition during the initial mitotic clonal expansion of the adipocyte differentiation process. While phosphorylation of the retinoblastoma protein (Rb) by cyclin/cdk complexes remains unaffected, oxidative stress decreases the expression of S-phase genes downstream of Rb. This silencing of S phase gene expression by increased oxidative stress is mediated through a transcriptional mechanism involving the inhibition of E2F recruitment and transactivation of its target promoters. Collectively, these data demonstrate a previously unrecognized role of oxidative stress in the regulation of adipogenesis which may contribute to age-associated adipose tissue dysfunction.
Persistent elevation of serum interleukin-6 in intraabdominal sepsis identifies those with prolonged length of stay.

Abstract Background/purpose Elevated serum interleukin-6 (IL-6) levels in patients with intraabdominal sepsis have been associated with increased morbidity and mortality. The authors hypothesized that after surgical intervention a persistent elevation of IL-6 would more accurately reflect the inflammatory state and thus predict the subsequent time to recovery better than the preoperative value alone. Methods Nineteen consecutive children with peritonitis and manifestations of the systemic inflammatory response syndrome were enrolled prospectively. IL-6 levels were determined from pre- and postoperative serum samples (within 12 to 24 hours) by enzyme-linked immunosorbant assay (ELISA). Patient postoperative length of stay (LOS) was recorded. Results Before surgery, patient serum IL-6 levels ranged from 48 to 132,546 pg/mL. LOS ranged from 4 to 60 days, with subjects falling into 2 groups of ≤11 (n = 14) and ≥25 (n = 5) days. Using an IL-6 level greater than 500 pg/mL to predict a prolonged LOS (>11 days), a persistent elevation of IL-6 postoperatively appears to increase the likelihood of a prolonged LOS. Conclusions Persistent IL-6 levels greater than 500 pg/mL may be useful in identifying pediatric intraabdominal sepsis patients with prolonged LOS and presumably greater morbidity. Rapid identification of these patients may allow for novel therapeutic interventions.
C 63 u NQR Measurement of Stripe Order Parameter in La 2 − x Sr x CuO 4

We demonstrate that one can measure the charge-stripe order parameter in the hole-doped ${\mathrm{CuO}}_{2}$ planes of ${\mathrm{La}}_{1.875}{\mathrm{Ba}}_{0.125}{\mathrm{CuO}}_{4}$, ${\mathrm{La}}_{1.48}{\mathrm{Nd}}_{0.4}{\mathrm{Sr}}_{0.12}{\mathrm{CuO}}_{4}$, and ${\mathrm{La}}_{1.68}{\mathrm{Eu}}_{0.2}{\mathrm{Sr}}_{0.12}{\mathrm{CuO}}_{4}$ utilizing the wipeout effects of ${}^{63}\mathrm{Cu}$ nuclear quadrupole resonance. Application of the same approach to ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{CuO}}_{4}$ reveals the presence of similar stripe order for the entire underdoped superconducting regime $\frac{1}{16}\ensuremath{\lesssim}x\ensuremath{\lesssim}\frac{1}{8}$.
Bi-modal imaging of atherosclerotic plaques: Automated method for co-registration between fluorescence lifetime imaging and intravascular ultrasound data

The risk of atherosclerosis plaque rupture cannot be assessed by the current imaging systems and thus new multi-modal technologies are under investigation. This includes combining a new fluorescence lifetime imaging (FLIm) technique, which is sensitive to plaque biochemical features, with conventional intravascular ultrasound (IVUS), which provides information on plaque morphology. In this study we present an automated method allowing for the co-registration of imaging data acquired based on these two techniques. Intraluminal studies were conducted in ex-vivo segments of human coronaries with a multimodal catheter integrating a commercial IVUS (40 MHz) and a rotational side-viewing fiber based multispectral FLIm system (355 nm excitation, 390±20, 452±22 and 542±25 nm acquisition wavelengths). The proposed method relies on the lumen/intima boundary extraction from the IVUS polar images. Image restoration is applied for the noise reduction and edge enhancement, while gray-scale peak tracing over the A-lines of the IVUS polar images is applied for the lumen boundary extraction. The detection of the guide-wire artifact is used for the angular registration between FLIm and IVUS data, after which the lifetime values can be mapped onto the segmented lumen/intima interface. The segmentation accuracy has been assessed against manual tracings, providing 0.120±0.054 mm mean Hausdorff distance. This method makes the bi-modal FLIm and IVUS approach feasible for comprehensive intravascular diagnostic by providing co-registered biochemical and morphological information about atherosclerotic plaques.
Gender differences in the impact of stressful life events on changes in body mass index.

Abstract Objective The positive association between stress and weight has been consistently demonstrated, particularly in women. The effect of stress on changes in weight, however, is less clear. Methods A total of 33,425 participants in Wave 1 and Wave 2 surveys of the National Epidemiologic Survey on Alcohol and Related Condition (NESARC) were included in this study. The study examined the relationship between stressful life events during the 12 months prior to the Wave 2 interview and changes in body mass index (BMI) between Wave 1 and Wave 2 interviews. Results Women reported significantly greater increases in BMI than men. Stressful life events, particularly job-related changes, legal problems, and death of family or friends, were associated significantly with increases in BMI among women but not men. Conclusions In a nationally representative sample, stressful life events were associated with greater weight gain in women. Prevention of weight gain in women should focus on the behavioral and physiological mechanisms underlying female-specific effects of stressful life events on weight gain.
A comprehensive meteorological modeling system?RAMS

This paper presents a range of applications of the Regional Atmospheric Modeling System (RAMS), a comprehensive mesoscale meterological modeling system. Applications discussed in this paper include large eddy simulations (LES) and simulations of thunderstorms, cumulus fields, mesoscale convective systems, mid-latitude cirrus clouds, winter storms, mechanically- and thermally-forced mesoscale systems, and mesoscale atmospheric disperision. A summary of current RAMS options is also presented. Improvements to RAMS currently underway include refinements to the cloud radiation, cloud microphysics, cumulus, and surface soil/vegetative parameterization schemes, the parallelization of the code, development of a more versatile visualization capability, and research into meso-α-scale cumulus parameterization.
A numerical method for simulating non-Newtonian fluid flow and displacement in porous media

Abstract Flow and displacement of non-Newtonian fluids in porous media occurs in many subsurface systems, related to underground natural resource recovery and storage projects, as well as environmental remediation schemes. A thorough understanding of non-Newtonian fluid flow through porous media is of fundamental importance in these engineering applications. Considerable progress has been made in our understanding of single-phase porous flow behavior of non-Newtonian fluids through many quantitative and experimental studies over the past few decades. However, very little research can be found in the literature regarding multi-phase non-Newtonian fluid flow or numerical modeling approaches for such analyses. For non-Newtonian fluid flow through porous media, the governing equations become nonlinear, even under single-phase flow conditions, because effective viscosity for the non-Newtonian fluid is a highly nonlinear function of the shear rate, or the pore velocity. The solution for such problems can in general only be obtained by numerical methods. We have developed a three-dimensional, fully implicit, integral finite difference simulator for single- and multi-phase flow of non-Newtonian fluids in porous/fractured media. The methodology, architecture and numerical scheme of the model are based on a general multi-phase, multi-component fluid and heat flow simulator — TOUGH2. Several rheological models for power-law and Bingham non-Newtonian fluids have been incorporated into the model. In addition, the model predictions on single- and multi-phase flow of the power-law and Bingham fluids have been verified against the analytical solutions available for these problems, and in all the cases the numerical simulations are in good agreement with the analytical solutions. In this presentation, we will discuss the numerical scheme used in the treatment of non-Newtonian properties, and several benchmark problems for model verification. In an effort to demonstrate the three-dimensional modeling capability of the model, a three-dimensional, two-phase flow example is also presented to examine the model results using laboratory and simulation results existing for the three-dimensional problem with Newtonian fluid flow.
Multifunctional Proteins: Calmodulin clarified

Genetic analysis in yeast is helping to dissect the multiple functions of calmodulin: mutations have been made that uncouple calmodulin from single targets among many.