cssi/SciSciGPT-SciSciNet huggingface dataset:
Adaptive parallel aggregation algorithms

Aggregation and duplicate removal are common in SQL queries. However, in the parallel query processing literature, aggregate processing has received surprisingly little attention; furthermore, for each of the traditional parallel aggregation algorithms, there is a range of grouping selectivities where the algorithm performs poorly. In this work, we propose new algorithms that dynamically adapt, at query evaluation time, in response to observed grouping selectivities. Performance analysis via analytical modeling and an implementation on a workstation-cluster shows that the proposed algorithms are able to perform well for all grouping selectivities. Finally, we study the effect of data skew and show that for certain data sets the proposed algorithms can even outperform the best of traditional approaches.
The collisio operator and long-time behavior of a perturbed two-body problem

The nature of the collision operator for a classical mechanical system whose dynamics is represented by a probability density satisfying the Liouville equation is illustrated with a soluble example. This example is that of a two-body problem with a particular perturbation. The collision operator $$\bar \psi (z)$$ is found and the time reversibility of the system is examined utilizing the analysis of Stey. For negative energies, the collision operator is zero in the limitz→i0+, while for zero energy, the collision operator is different from zero in that limit. This indicates that the system is reversible for negative energy and irreversible for zero energy.
A stochastic model of skeletal muscle based on motor unit properties

Skeletal muscle force generation stochastic model based on motor unit, discussing Poission distribution and dynamic force response
Pursuit Meter II, a Computer-Based Device for Testing Pursuit-Tracking Performance:

The Pursuit Meter II, a microcomputer-based device developed for the quantitative determination of human pursuit-tracking performance, is described. Computer-generated moving patterns are displayed on a high resolution color video monitor. For the subject the task is to attempt to superimpose a red line presented on the screen, the vertical location of which he controls with a steering device, over a blue line the computer generates as the problem. Both lines, each composed of 279 segments, are generated at the same rate, left to right on the monitor. The individual differences between the subject's response and the problem are summed and stored by the computer as an error score which correlates inversely to the subject's ability to perform the task. Three Pursuit Meter II problems were presented to 26 male college students. Our data demonstrated that different levels of performance to the problems resulted and that the Pursuit Meter II can be used to quantify human pursuit-tracking performance.
Expected time analysis of interpolation merge — a simple new merging algorithm

Abstract Binary merge is the best general-purpose merging algorithm known to date. Binary merge consists of two components: a first component in which an array index is incremented by a number nearly equal to the ratio of the sizes of the two arrays being merged followed by a second component, binary search. In this paper we formulate a simple algorithm called interpolation merge, where the binary search component is replaced with linear search, and analyze its expected behavior over data drawn from a uniform distribution. Our results, both theoretical and experimental, indicate a constant factor (≈0.75) speed-up over straight two-way merge. Further, our analysis of interpolation merge, which uses a mechanism of incremental indexing similar to that in binary merge, will hopefully lead to a better understanding of the latter algorithm. Currently, no significant results are known about the expected behavior of binary merge over data drawn from any standard probability distribution.
Olivine-liquid equilibria and the chemical activities of FeO, NiO, Fe2O3, and MgO in natural basic melts

The distribution of the cations Fe+2, Mg+2, Ni+2, Mn+2, and Ca+2 between olivine and natural basic liquid is experimentally explored at one atmosphere as functions of oxygen fugacity, temperature, and composition. By performing the experiments in equilibrium with NiFe alloys, the chemical activities of FeO, Fe2O3, and NiO were monitored in the melt and from knowledge of the thermodynamics of olivine mixing, the activity of MgO was also calculated. This is the first time that the activity of Fe2O3 has been monitored in a natural melt and also the first observations of the variation of aFeO with oxygen fugacity. Empirical models for the variation of the activities of these components as functions of oxygen fugacity, temperature, and composition are presented and the models for FeO and MgO are shown to be able to predict the olivine composition. The partition coefficients for FeO, MgO, NiO, and MnO for olivine were found to be invariant over more than 9 orders of magnitude in oxygen fugacity. The calcium partition coefficient decreases with increasing fO2, but this is due to the changing olivine composition with oxygen fugacity. Nickel, manganese, and calcium partitioning are functions of composition and temperature, although thermodynamic analysis shows that the temperature variation for NiO and MnO is primarily due to the temperature dependence of the activity coefficients rather than a large enthalpy of the exchange reactions. Empirical predictive models are presented for the partition coefficients of all of the divalent cations.
Simulation of Endovascular Neurointervention Using Silicone Models : Imaging and Manipulation

Silicone models of cerebral aneurysm and stroke pathology were produced by copying the images of clinical cases to evaluate the simulation of endovascular procedures. Conventional silicone models, silicone suture models made from separate aneurysm sac and parent artery sutured together, and animal vascular models made from vessels obtained from pigs were made. The models were incorporated in the training system for simulation of endovascular procedures under digital subtraction angiography control using a portable angiography system. The conventional silicone models provided very close reproduction of the aneurysm and vessels, even the fine branches. However, greater resistance or impact was felt, especially when passing the device through curved vessels. Stroke models were insufficiently dilated by percutaneous transluminal angioplasty or stenting. The silicone suture model was useful to avoid damage to models of giant aneurysm or models with small orifices during the lost wax procedure, whereas the projection of domes was somewhat inaccurate. The animal vascular model could not provide accurate aneurysm shape and vessel diameter, although the feel during manipulation was much more realistic.
Secondary CD8+ T-cell responses are controlled by systemic inflammation.

Repeated infections and experimental prime-boost regimens frequently result in the generation of secondary (2°) CD8+ T-cell responses. In contrast to primary (1°) CD8+ T cells, the parameters that influence the abundance and phenotype of 2° effector and memory CD8+ T-cell populations are largely unknown. Here, we analyze the impact of different booster infections, Ag curtailment, and systemic inflammation on the quality and quantity of secondary CD8+ T-cell responses. We show that similar to 1° CD8+ T-cell responses, the phenotype of 2° effector and memory CD8+ T-cell populations is critically dependent on the nature of the infectious pathogen and the inflammatory milieu early after infection. In addition, systemic inflammation increases the number of 2° effector and memory CD8+ T cells after booster infections and immunizations. Therefore, our data reveal new means to boost the number of 2° effector and memory CD8+ T cells in prime-boost regimens and show a surprisingly high degree of plasticity in 2° memory CD8+ T-cell phenotype that is controlled by systemic inflammation.
The Vicious Cycle: Recurrent Interactions Among the Media, Politicians, the Public, and Child Welfare Services Organizations

The vicious cycle is a sequence of events that recurs to varying degrees throughout the United States. The cycle includes interactions among the media, politicians, the public, and child welfare services organizations in response to grievous incidents of child maltreatment. These interactions have a profound impact on child welfare services organizations and those who work in them. The cycle and the influence it has on child welfare services organizations are explored with a focus on the climates and cultures in those organizations, the cycle's impact on the child welfare services workforce, and the services they provide. Proposed solutions for managing the effects of the cycle on child welfare services organizations are also considered.
Distributed Collaborative Adaptive Sensing: A Unifying Theme for a Junior Level Embedded Systems Course.

A new junior level embedded systems course uses the notion of Distributed Collaborative Adaptive Sensing as a unifying theme. The content of the course is inspired by research in weather radar networks but is mapped to an imaging system for a more manageable and tangible application. "Big-picture" lectures present concepts and applications in modern embedded systems. The labs involve problem solving in sensor data acquisition, signal processing and networked computing. The Altera DE2 board with System on Programmable Chip (SOPC) development platform, the NIOS softcore [1] and other peripherals is used along with a digital camera [7]. Assessment of the outcomes and impressions of the course indicates a significant improvement over a more traditional embedded systems course. The course materials are available online [2].
Detectability limit and uncertainty considerations for laser induced fluorescence spectroscopy in flames

Uncertainty relations are derived for fluorescence caused by laser excitation in flames. The effect of statistical and systematic uncertainties on the detectability limits for excited states are examined. Fluorescence trapping is discussed and shown to establish an upper limit on the number density that can be measured. Methods for minimizing the trapping effect are discussed.
Citrobacter meningitis in adults

Citrobacter meningitis is an uncommon infection of neonates and young children. It is rarely seen in adults. We describe a 46-year-old man with a mixed bacterial meningitis caused by C. diversus and Klebsiella oxytoca and a 64-year-old woman with C. freundii meningitis. Review of the English-language literature revealed only 2 adult patients with C. diversus meningitis and another 2, with C. freundii meningitis. The ages of these 6 aforementioned patients ranged from 31 to 84 years. Multiple facial fractures, neurosurgical procedures, alcoholism and diabetes mellitus were predisposing conditions. Among the 5 patients whose outcome was known, antibiotic therapy was successful in 4 but failed in 1. This study emphasizes that almost any of the gram-negative bacilli can cause serious infection of the central nervous system in adults in the proper setting.
Target Immunity during Mu DNA Transposition: Transpososome Assembly and DNA Looping Enhance MuA-Mediated Disassembly of the MuB Target Complex

The Mu transpososome can distinguish between proximal and distal DNA during the selection of a site for transposition. This phenomenon, termed target immunity, involves MuA-stimulated removal of MuB oligomers from sites near the Mu genome. Using a combination of ensemble and single-molecule fluorescence methods, we show that the MuA tetramer can stably associate with the DNA-bound MuB oligomer and is more efficient than monomeric MuA at stimulating the dissociation of MuB from DNA. In addition, we demonstrate that DNA looping is essential for efficient disassembly of the MuB oligomer. We propose a model in which the MuA tetramer forms a multivalent complex with the MuB oligomer and catalyzes the processive removal of MuB from DNA.
Teachers should go back to school

Talking About Leaving: Why Undergraduates Leave the Sciences byElaine Seymour andNancy M. Hewitt Westview Press: 1996. Pp. 429. $49.95, £37
A postulated mechanism for the bioluminescent oxidation of reduced flavin mononucleotide.

Abstract A mechanism is presented for the luciferase catalyzed oxidation of reduced flavin mononucleotide with oxygen in the presence of long-chain aldehyde. The mechanism involves the formation of a flavin peroxy anion which attacks aldehyde. A Baeyer-Villiger type shift leads to oxidation of aldehyde to acid, and to formation of hydroxide and excited protonated flavin which emits a photon. The mechanism is consistent with known details of the bioluminescent reaction and with known reactions of flavins and allows several verifiable predictions to be made.
Quantification of the familial contribution to juvenile idiopathic arthritis

Objective We previously demonstrated that there is familial aggregation of juvenile idiopathic arthritis (JIA). Using a large JIA cohort, we sought to identify additional clusters of JIA cases and to calculate robust estimates of the relative risk (RR) of JIA in the siblings and cousins of JIA probands. We also estimated the population attributable risk (PAR) of familial factors in JIA. Methods A probabilistic record-linking analysis was performed by matching the records of 862 patients with JIA with the records of ∼7 million individuals in the Utah Population Database (UPDB), a computerized genealogic database. For each patient, 5 control subjects matched for birth year and sex were selected from the UPDB. Specialized software was used to test for familial aggregation of disease, to estimate the magnitude of familial risks, and to identify families at high risk of disease. Results We identified 22 founders who had significantly more descendants with JIA than expected (5–13 descendants; P values ranged from <0.0001 to <0.008). The PAR of familial factors for JIA was ∼13%. The RR of JIA in the siblings of patients was significantly increased (11.6, 95% confidence interval [95% CI] 4.9–27.5, P < 2.59 × 10−8). The RR of JIA in first cousins was also increased (5.82, 95% CI 2.5–13.8, P < 6.07 × 10−5). Conclusion We have identified the largest sets of JIA pedigrees described to date. Approximately 13% of cases of JIA can be attributed to familial factors. Siblings and first cousins of probands with JIA have an increased risk of JIA. The observed decline in the magnitude of risk between siblings and cousins suggests that JIA is influenced by shared genetic factors.
Free rider estimation : refining the use of surveys

Abstract The accurate measurement of free ridership is a significant issue for evaluators and program managers of demand-side management programs. The use of survey questionnaires will continue to be a cost-effective, although limited, approach in determining the level of free ridership. The use of innovative questionnaire designs and questions will enable researchers to reduce the level of uncertainty regarding free ridership. We examine the issue of free ridership through the use of multiple questions and through sectoral analysis.
Abduction with (Dis)honor: Sovereigns, Brigands, and Heroes in the Ottoman World

This essay is interested in the ways in which acts of abduction, their significations, and the identities of abductors changed over the course of the sixteenth and seventeenth centuries. At the start of this period, abduction was a positive force for the honor and reputation of the Ottoman sultanate, but it gradually turned into an act that threatened the state’s authority. Powerful abductors—those whose deeds aroused public admiration or alarm, or perhaps both—are our principal subject. If at the start of the sixteenth century abduction was an act that could enhance a monarch’s renown, it was losing its force as emblematic conduct of the royal victor. By the mid-century, the ideal sultan was less a warrior of legendary prowess than a prudent statesman more interested in treaties with his enemies than personal violence against them. Moreover, he was now the prosecutor of abduction. Around 1540, imperial law began to crack down on abduction by prescribing the dire punishment of castration. As if in response, the uses of abduction as a public assertion of honor, power and valor began to be appropriated by opponents of the government’s vision of order—rebels and disaffected servants of the state.
The Role of Motivational Values in the Construction of Change Messages.

We examined how 106 early-career professionals constructed video change messages involving a ban on remote working. These professionals constructed three types of statements: vision statements, dir...
Differential tumor suppressor properties and transforming growth factor- β responsiveness of p57KIP2 in leukemia cells with aberrant p57KIP2 promoter DNA methylation

To investigate if the tumor suppressor properties of p57KIP2 are dependent on its DNA methylation status, we studied the impact of several stress stimuli in leukemic cell lines with different p57KIP2 promoter DNA methylation levels. p57KIP2 reactivation was observed after stimulation with transforming growth factor-β, other cytokines, high-density culture or serum withdrawal in p57KIP2 promoter unmethylated cells but not in methylated cells. In these cells, p57KIP2 reactivation required the use of a hypomethylating agent or a histone deacetylase inhibitor. Overexpression of p57KIP2 in p57KIP2 promoter methylated leukemic cell lines resulted in cell growth arrest and the induction of apoptosis. In contrast, overexpression of p57KIP2 in partially methylated cells only resulted in a moderate inhibition of cell growth and had no impact on apoptosis. Transduction of unmethylated cells expressing high levels of p57KIP2 with p57KIP2 short hairpin RNA resulted in increased cell proliferation. These results suggest that the tumor suppressive properties of p57KIP2 in leukemia may depend on the intrinsic promoter DNA methylation status of the gene.
Fetal alcohol syndrome: the vulnerability of the developing brain and possible mechanisms of damage

Fetal alcohol exposure has multiple deleterious effects on brain development, and represents a leading known cause of mental retardation. This review of the effects of alcohol exposure on the developing brain evaluates results from human, animal andin vitro studies, but focuses on key research issues, including possible mechanisms of damage. Factors that affect the risk and severity of fetal alcohol damage also are considered.
A nonsynergistic strain of a granulosis virus of the armyworm, Pseudaletia unipuncta☆

Abstract A granulosis virus isolated in Hawaii from the larva of the armyworm, Pseudaletia unipuncta , acts as a synergist and enhances the nuclear-polyhedrosis virus in infecting the armyworm larva. On the other hand, a granulosis virus obtained from Oregon (probably collected in California) is not capable of enhancing the nuclear-polyhedrosis virus. This difference in the synergistic property is not directly associated with the virulence of the viruses from the two separate sources. The virus from Hawaii at a concentration below its infectious dose does not enhance the nuclear-polyhedrosis virus. The viruses from the two sources also differ in the lengths of the virus rod enclosed within a developmental membrane and of the capsule. On the basis of differences in their synergistic property and in their sizes, the granulosis viruses from the two sources are considered as separate strains.
An overview of the assessment of aquatic ecosystem health using benthic invertebrates

Community structure or species composition of benthic invertebrates has frequently been used in environmental monitoring and assessment of aquatic systems. Three general approaches have been taken: the ‘saprobic’ approach, which requires detailed knowledge of taxonomy and is most effective in measuring impacts from sewage effluents; diversity indices, which do not require detailed knowledge of species requirements but ignore information provided by important species and tend to lose information; and biotic indices, which combine both approaches. In the past few years considerable advances have been made by applying multivariate statistical techniques to large data matrices and relating benthic community structure to key environmental variables. Using these techniques it is possible to establish reference communities for a set of environmental conditions, to predict the benthic community that should occur at new sites and thus measure deviation from an expected community type. This suggests that environmental criteria and objectives can be established based on biological variables as opposed to the more traditional chemical approach.
The cytoarchitecture of the brain stem of the domestic pig

The cytoarchitecture and topography of some brain stem nuclei of the pig have been studied intransversely and sagitally cut, Nissl and Weigert stained, semiserial section. The cytology of those brain stem nuclei which receive an afferent supply from the ventrolateral funculus of the spinal cord is described. This study was found to be a necessary prologue to the study of distribution and terminations of spinal cord afferents to the brain stem in this species. The recognition of a nuclear pattern within the brain stem of the pig which is quite similar to that described in other species is noted.
Crystallization and preliminary X-ray data for peanut agglutinin

Lectins are polyvalent carbohydrate-binding proteins that can agglutinate cells having the appropriate saccharides on their surfaces. Although they were discovered in plants, lectins are found in all types of living organisms. Their biological functions are not completely understood, but they tend to be involved in interactions with components of the cell surface or the extracellular environment [l]. There are several hypotheses regarding their functions. In plants, lectins may participate in binding of nitrogen-fixing bacteria to the roots of legumes [2,3] and in defense against infection [4]. In animals, lectins may also serve protective function [5], as well as roles in receptor-mediated pinocytosis of partially degraded glycoproteins [6] and in intercellular recognition during differentiation [7]. Because of the specificity of their interactions with the carbohydrate moieties of glycolipids and glycoproteins, lectins have played an increasingly important role in studies of membranes from normal and cancerous cells [8], blood typing and the study of blood group substances [8], the purification of glycoproteins and polysaccharides [8] and the triggering of lymphocytes to undergo blastogenesis [9]. Peanut agglutinin (PNA) is a lectin that is specific for terminal D-galactosyl residues [ 10,l l] with an additional preference for N-acetylgalactosamine in the penultimate position [lo]. This specificity allows the use of PNA to detect the T-antigen on erythrocyte surfaces [ 121, to study T lymphocyte subpopulations [13], and to separate mature and immature thymocytes [ 141. The physical properties of PNA have been examined by circular dichroism, gel chromatography and sedimentation techniques [15]. It is a tetramer of Mr 98 000. The circular dichroism spectrum of PNA changes in the near ultraviolet upon binding lactose; whereas, the far ultraviolet spectrum remains unchanged [ 151. The thermodynamic parameters, which have been determined by ultraviolet difference spectroscopy, are similar to those of other plant lectins [ 161. The first forty residues have been sequenced and are homologous to the sequences of lectins from ten other leguminous plants [17]. The homology to concanavalin A (Con A) is particularly interesting since the amino terminal residue of PNA would be aligned with residue 123 of Con A. There are additional similarities between these two proteins in their metal binding properties [ 161 and CD spectra WI. In this paper we are reporting conditions for the crystallization of PNA in the presence and absence of lactose. The crystals of the PNA-lactose complex are suitable for structural analysis, and their space group has been determined.
Target energy effects on Type 1 and Type 2 visual persistence

The effects of varying target energy (luminance and duration) were determined for two different types of visual persistence. Type 1 persistence, which reflects the latency for perceived offset of a brief stimulus, was found to be inversely related to target energy. Type 2 persistence, which reflects the total perceived duration of the fading stimulus trace, was found to be positively related to target energy. These results for both types of persistence were established with the common asynchrony-judgment task and with a simple reaction time task. The opposite relationships for the two types of visual persistence with target-energy manipulations were discussed in terms of: (1) the different processes believed to underlie Type 1 and Type 2 persistences and (2) the disparate empirical results frequently reported in the current persistence literature.
The isolation of strand-specific nicking endonucleases from a randomized SapI expression library

The Type IIS restriction endonuclease SapI recognizes the DNA sequence 5'-GCTCTTC-3' (top strand by convention) and cleaves downstream (N1/N4) indicating top- and bottom-strand spacing, respectively. The asymmetric nature of DNA recognition presented the possibility that one, if not two, nicking variants might be created from SapI. To explore this possibility, two parallel selection procedures were designed to isolate either top-strand nicking or bottom-strand nicking variants from a randomly mutated SapI expression library. These procedures take advantage of a SapI substrate site designed into the expression plasmid, which allows for in vitro selection of plasmid clones possessing a site-specific and strand-specific nick. A procedure designed to isolate bottom-strand nicking enzymes yielded Nb.SapI-1 containing a critical R420I substitution near the end of the protein. The top-strand procedure yielded several SapI variants with a distinct preference for top-strand cleavage. Mutations present within the selected clones were segregated to confirm a top-strand nicking phenotype for single variants Q240R, E250K, G271R or K273R. The nature of the amino acid substitutions found in the selected variants provides evidence that SapI may possess two active sites per monomer. This work presents a framework for establishing the mechanism of SapI DNA cleavage.
Aluminum-27 NMR study of some AlCl3−MCl molten systems

Aluminum-27 NMR was used to investigate AlCl3−MCl (M=Li, Na, K, Butylpyridinium) molten mixtures. In AlCl3 rich mixtures, the27Al resonance line was resolved into two components corresponding to the AlCl4− and Al2Cl7− species, which were shown to undergo chemical exchange line broadening. This broadening was found to be cation and temperature dependent.
Genetic Transfer Systems for Delivery of Plasmid Deoxyribonucleic Acid to Lactobacillus acidophilus ADH: Conjugation, Electroporation, and Transduction

Lactobacillus acidophilus ADH is a bacteriocin-producing human isolate that adheres to human fetal intestinal cells and human ileal cells. We have employed both electroporation and conjugation methodologies to transfer various plasmids to L. acidophilus ADH. Furthermore, we have demonstrated transduction of plasmid DNA within this strain by a temperate bacteriophage (phi adh) harbored by L. acidophilus ADH. Plasmid pGK12 was introduced into strain ADH by electroporation at frequencies as high as 3.3 X 10(5) transformants/micrograms of plasmid DNA. Transconjugants of strain ADH were recovered at frequencies of 10(-2) (pAMB1), 10(-4) (pVA797::Tn917), and 10(-4) (pVA797) per donor cell after filter-mating with Lactococcus lactis ssp. lactis. Plasmid pGK12 was transduced from a phage phi adh lysogen into a recipient strain of L. acidophilus ADH at an average frequency of 3.4 X 10(-8) transductants/pfu. Transformants, transconjugants, or transductants were verified by both phenotype and plasmid profile for acquisition of plasmid DNA. The ability to transfer plasmids and mobilize DNA sequences by electroporation, conjugation, and transduction will augment our efforts to define and characterize the activities of L. acidophilus in the intestinal tract.
Congenital heart diseases: post-operative appearance on multi-detector CT—a pictorial essay

Echocardiography is considered as an initial imaging modality of choice in patients with congenital heart disease (CHD), and magnetic resonance (MR) imaging is preferred for detailed functional information. Multi-detector computed tomography (CT) plays an important role in clinical practice in assessing post-operative morphological and functional information of patients with complex CHD when echocardiography and MR imaging are not contributory. Radiologists should understand and become familiar with the complex morphology and physiology of CHD, as well as with various palliative and corrective surgical procedures performed in these patients, to obtain CT angiograms with diagnostic quality and promptly recognise imaging features of normal post-operative anatomy and complications of these complex surgeries.
1178 PULMONARY SUPEROXIDE DISMUTASE (PSOD) ACTIVITY IN THE EUTHYROID (E) AND ATHYROTIC (Tx) OVINE FETUS

Animal studies have shown that the development of pulmonary oxygen toxicity is enhanced in the hyperthyroid and delayed in the hypothyroid state. PSOD activity was studied in 5 E at 130 and 5 E at 140 days (d) gestation and compared to 5 Tx at 130 and 5 Tx at 140 d gestation. All Tx were surgically thyroidectomized at 95 to 99 d gestation. Although the Tx lung contained an increase number of smaller sized cells compared to E, there was no change in cell number or size within the Tx or E groups from 130 to 140 d. The PSOD activity per cell was decreased in E from 130 to 140 d, but tended to increase in Tx. Thus, in E, PSOD activity per cell decreases with increasing gestational age. Hypothyroidism in the ovine fetus during the last trimester retards fetal lung growth and alters PSOD activity.
Gallop: the benefits of wide-area computing for parallel processing

Abstract Internet computing has emerged, as an attractive paradigm for many applications that require access to distributed resources such as telemedicine, collaboratories, and transaction systems. For applications that require high performance, the Internet is assumed to be inappropriate. However, it is possible to obtain high performance for parallel scientific applications in an Internet environment. A wide-area scheduling system called Gallop has been developed to exploit opportunities for high performance using remote Internet resources for these applications. This paper describes the Gallop architecture and scheduling model, and performance results obtained for three parallel applications. The initial results indicate that wide-area parallel processing can lead to better performance even with Internet technology, but that current Internet bandwidth is a major bottleneck for file and binary transfer. This overhead limits the class of suitable applications to those that are large-grained or that will be run multiple times to amortize the transfer cost.
Temperature-Controlled Depth Profiling of Poly(methyl methacrylate) Using Cluster Secondary Ion Mass Spectrometry. 1. Investigation of Depth Profile Characteristics

Secondary ion mass spectrometry employing an SF5+ polyatomic primary ion source was used to depth profile poly(methyl methacrylate) (PMMA) at a series of temperatures ranging from −75 °C to 125 °C, where the primary glass transition for PMMA occurs at 105 °C. The depth profile characteristics (e.g., interface widths, sputter rates, damage accumulation factors, normalized intensities, and overall secondary ion stability or constancy) were monitored as a function of temperature. It was found that, at low temperatures, the quality of the depth profiles improved considerably, having decreased damage accumulation, higher normalized intensities, and decreased interface widths, particularly at −75 °C. Higher temperatures were correlated with increased sputter rates. However, the improvements in interfacial widths and decreased damage accumulation were not as prevalent as observed at low temperatures. The importance of glass transition temperature (Tg) on the depth profile characteristics was also apparent. The r...
Validation of the Hoffmann and Edwards' S(IV)-H2O2 mechanism

Abstract Hoffmann and Edwards' (1975) theoretical expression for the second order rate constant of the oxidation of dissolved S(IV) by H 2 O 2 was successfully fit to data from six different experiments.
Native American Art: The Collections of the Ethnological Museum Berlin/Sun Dogs and Eagle Down: The Indian Paintings of Bill Holm

Native American Art: The Collections of the Ethnological Museum Berlin, Peter Bolz and Hans-Ulrich Sanner Seattle: University of Washington Press, 1999.240 pp. 162 color and 65 black and white photos, bibliography, index. $40.00 (paper). Sun Dogs and Eagle Down: The Indian Paintings of Bill Holm, Steven C. Brown and Lloyd J. Averill Seattle: University of Washington Press, 2000.x. 198 pp. 76 color photos, notes, bibliography. $35.00 (cloth).
A Classification of Spatial Stiffness Based on the Degree of Translational–Rotational Coupling

Previously, we have shown that, to realize an arbitrary spatial stiffness matrix, spring components that couple the translational and rotational behavior along/about an axis are required. We showed that, three such coupled components and three uncoupled components are sufficient to realize any full-rank spatial stiffness matrix and that, for some spatial stiffness matrices, three coupled components are necessary. In this paper, we show how to identify the minimum number of components that provide the translational-rotational coupling required to realize an arbitrarily specified spatial stiffness matrix. We establish a classification of spatial stiffness matrices based on this number which we refer to as the degree of translational-rotational coupling (DTRC). We show that the DTRC of a stiffness matrix is uniquely determined by the spatial stiffness mapping and is obtained by evaluating the eigenstiffnesses of the spatial stiffness matrix. The topological properties of each class are identified. In addition, the relationships between the DTRC and other properties identified in previous investigations of spatial stiffness behavior are discussed.
Elevated body temperature directly contributes to heat stress infertility of broiler breeder males

Alterations in the male reproductive tract, sperm, or both may be responsible for heat stress infertility of broiler breeder males. The present study was conducted to determine the direct effects of hyperthermia during heat stress on sperm viability, the spermquality index (SQI), and seminal plasma ion concentrations by incubation of semen in vitro at and above normal body temperature. Thirty-seven Cobb males were divided into the upper (best group = B) and lower (poor group = P) 50% of the population according to their SQI. Semen characteristics and seminal plasma ion concentrations (Ca++, Na+, K+, and Cl-) for B and P males were evaluated at two temperature treatments (41.5 and 42.5 C) and four incubation times (0, 30, 60, and 90 min). The results revealed that sperm viability and the SQI were decreased by increasing incubation temperature and duration of exposure. Seminal plasma ion concentrations were not affected by semen incubation temperature; however, plasma Ca++ concentration in the P-SQI group was higher than that of the B-SQI group. Seminal plasma K+ concentration increased in both SQI groups over time. In conclusion, it is apparent that changes in semen characteristics due to elevated body temperature alone contribute to heat stress infertility of broiler breeders.
The Undirected Incomplete Perfect Phylogeny Problem

The incomplete perfect phylogeny (IPP) problem and the incomplete perfect phylogeny haplotyping (IPPH) problem deal with constructing a phylogeny for a given set of haplotypes or genotypes with missing entries. The earlier approaches for both of these problems dealt with restricted versions of the problems, where the root is either available or can be trivially reconstructed from the data, or certain assumptions were made about the data. In this paper, we deal with the unrestricted versions of the problems, where the root of the phylogeny is neither available nor trivially recoverable from the data. Both IPP and IPPH problems have previously been proven to be NP-complete. Here, we present efficient enumerative algorithms that can handle practical instances of the problem. Empirical analysis on simulated data shows that the algorithms perform very well both in terms of speed and in terms accuracy of the recovered data.
A Dominant Negative Inhibitor of the Egr Family of Transcription Regulatory Factors Suppresses Cerebellar Granule Cell Apoptosis by Blocking c-Jun Activation

To investigate the role of the Egr family of transcription regulatory factors in neuronal apoptosis, we examined the effect of a dominant negative Egr inhibitor construct in a well characterized in vitro paradigm, cerebellar granule cell death induced by withdrawal of depolarizing concentrations of extracellular potassium. We found that this apoptotic stimulus increases the activity of a reporter gene driven by the Egr response element and that a dominant negative inhibitor of Egr-mediated transcription blocks granule cell apoptosis. In contrast, apoptosis of immature granule cells induced by cytosine arabinoside is not inhibited by the Egr inhibitor construct. Because activation of c-Jun is an essential step in granule cell death induced by potassium deprivation, but not cytosine arabinoside, we asked whether the Egr inhibitor acts by influencing c-Jun activation or its ability to induce apoptosis. We found that the Egr inhibitor does not block the ability of a constitutively active c-Jun construct to induce apoptosis in these cells but does suppress activation of c-Jun-mediated transcription induced by lowering extracellular potassium concentration. Furthermore, the Egr inhibitor blocks the ability of MEKK1 [mitogen-activated protein kinase (MAPK) kinase kinase 1], an upstream kinase capable of stimulating the JNK (c-Jun N-terminal protein kinase)–c-Jun pathway, to induce apoptosis and activate c-Jun. Together, these studies indicate that the Egr family of transcription factors plays a critical role in neuronal apoptosis and identify c-Jun activation as an important downstream target of the Egr family in this process.
Robust speech recognition using a Small Power Boosting algorithm

In this paper, we present a noise robustness algorithm called Small Power Boosting (SPB). We observe that in the spectral domain, time-frequency bins with smaller power are more affected by additive noise. The conventional way of handling this problem is estimating the noise from the test utterance and doing normalization or subtraction. In our work, in contrast, we intentionally boost the power of time-frequency bins with small energy for both the training and testing datasets. Since time-frequency bins with small power no longer exist after this power boosting, the spectral distortion between the clean and corrupt test sets becomes reduced. This type of small power boosting is also highly related to physiological nonlinearity. We observe that when small power boosting is done, suitable weighting smoothing becomes highly important. Our experimental results indicate that this simple idea is very helpful for very difficult noisy environments such as corruption by background music.
How many mechanisms do regulatory T cells need

A plethora of new regulatory T cell (Treg) mechanisms have recently emerged. This raises two important questions. First, how many molecules or mechanisms are required for Treg to work? Second, how should we evaluate the contribution of any given Treg molecule/mechanism and how is this likely to relate (or not) to the phenotype seen in Scurfy/Foxp3-deficient mice? In this discussion piece, I will briefly outline our current understanding of the Treg arsenal and address these important questions.
Post-anoxic myoclonus: A case presentation and review of management in the rehabilitation setting

Post-anoxic myoclonus is a rare movement disorder manifested by diffuse action-triggered jerking movements that may result in significant disability. The incidence of this disorder is not clearly established, but over 122 cases have so far been reported in the literature. The pathogenesis is not entirely known, although it has been hypothesized that particular susceptibility of the Purkinje cells of cerebellum to anoxic injury may play a key role. A case is presented of an independently living 60-year-old woman admitted to the rehabilitation unit with diffuse myoclonus after sustaining a cardio-pulmonary arrest. She presented with severe jerking movements in all extremities with startle to noise and exacerbations upon attempting any purposeful actions. The patient's myoclonus was controlled by a variety of anti-epileptic medications. The patient initially responded to a combination of divalproex sodium and zonisamide, but relapsed in several weeks, requiring addition of levetriacetam and clonazepam. At a 1-year follow-up she demonstrated a significant improvement in ambulation and self-care activities. This case illustrates that, although patients with post-anoxic myoclonus cannot be fully cured, their quality of life can be significantly improved by rehabilitation interventions.
Postoperative Troponin Screening: A Cardiac Cassandra?

The cardiovascular management of the patient undergoing noncardiac surgery has been in evolution for the last 35 years. Over this time frame, 2 secular trends have advanced in parallel but provided contrary practice implications for the care of the surgical patient. First, cardiovascular event rates have been dropping significantly over time. In 1977, Goldman et al1 created a risk evaluation system that predicted a 22% rate of life-threatening cardiovascular events and >50% mortality in the highest-risk group in 1001 patients undergoing surgery. These rates of events have dropped significantly each decade since. Finks et al2 reported 2 years ago a mere 2.8% national mortality rate for open abdominal aortic aneurysm repair, the exemplar of routine, high-risk surgery. These numbers were recapitulated worldwide for high-risk patients undergoing noncardiac surgery in the Perioperative Ischemic Evaluation (POISE) trial.3 Improvements in surgical and anesthetic techniques, perioperative medical therapy, and intensive care have contributed to the significant improvement in outcomes. Article see p 2264 Second, the sensitivity of testing to detect evidence of cardiovascular disease or ischemia has increased dramatically. In this same time frame, risk assessment has evolved from stress testing to nuclear-vasodilator testing, inotropic echocardiographic assessment, cardiac magnetic resonance imaging, and positron emission tomographic scanning. Counterintuitively, the ability to accurately detect smaller and smaller amounts of disease has not improved postoperative cardiovascular event prognostication. Indeed, the positive predictive value for each of these modalities in predicting a cardiovascular event remains <20%.4 The poor performance may be attributed to 2 components. First, improvements in disease detection foster inclusion of patients previously deemed healthy by less sensitive modalities. Indeed, it is the specific coronary heart disease detection improvement that undermines its prognostic value in the stable patient by diminishing the risk of the group with a positive study. Second, ever-dropping event …
Comparing parallel performance of Go and C++ TBB on a direct acyclic task graph using a dynamic programming problem

Concurrent programming languages Go and C++ Threading Building Blocks (TBB) offer high level parallel programming mechanisms built on top of threads. Go goroutines and TBB task classes are used as the computation units that are mapped to physical threads on multi-core processors. The synchronization mechanisms in Go and TBB are the channel and the task scheduler, respectively. We utilized these mechanisms to implement a parallel version of the optimal binary search tree dynamic programming algorithm in Go and TBB. Both implementations tile the iteration space and construct and evaluate a direct acyclic task graph for optimal parallelism without over constraints. We compared Go and TBB speedup and performance to create a benchmark of how efficient these two languages are at evaluating a direct acyclic task graph. Our experimental results show that the overhead of task scheduling and synchronization in TBB is much smaller than Go and that the overall performance of TBB is 1.6 to 3.6 times faster than Go. TBB provided super linear speedup under certain conditions, which we attribute to the majority of the test data being cached and the negative cost of task scheduling and synchronization. We conclude that TBB task scheduling and synchronization is faster than Go and that the top speedup of TBB is greater than that of Go.
Dynamic Assortment Customization with Limited Inventories

We consider a retailer with limited inventory of identically priced, substitutable products. The retailer faces a market with multiple segments of customers that are heterogeneous with respect to their product preferences. Customers arrive sequentially, and the firm decides which subset of products to offer to each arriving customer depending on the customer’s preferences, the inventory levels, and the remaining time in the season. We show that it is optimal to limit the choice set of some customers (even when the products are in stock), reserving products with low inventory levels for future customers who may have a stronger preference for those products. In certain settings, we prove that it is optimal to follow a threshold policy under which a product is offered to a customer segment if its inventory level is higher than a threshold value. The thresholds are decreasing in time and increasing in the inventory levels of other products. We introduce two heuristics derived by approximating the future margi...
The Dickeya dadantii biofilm matrix consists of cellulose nanofibres, and is an emergent property dependent upon the type III secretion system and the cellulose synthesis operon

Dickeya dadantii is a plant-pathogenic bacterium that produces cellulose-containing biofilms, called pellicles, at the air–liquid interface of liquid cultures. D. dadantii pellicle formation appears to be an emergent property dependent upon at least three gene clusters, including cellulose synthesis, type III secretion system (T3SS) and flagellar genes. The D. dadantii cellulose synthesis operon is homologous to that of Gluconacetobacter xylinus, which is used for industrial cellulose production, and the cellulose nanofibres produced by D. dadantii were similar in diameter and branching pattern to those produced by G. xylinus. Salmonella enterica, an enterobacterium closely related to D. dadantii, encodes a second type of cellulose synthesis operon, and it produced biofilm strands that differed in width and branching pattern from those of D. dadantii and G. xylinus. Unlike any previously described cellulose fibre, the D. dadantii cellulose nanofibres were decorated with bead-like structures. Mutation of the cellulose synthesis operon genes resulted in loss of cellulose synthesis and production of a cellulase-resistant biofilm. Mutation of other genes required for pellicle formation, including those encoding FliA (a sigma factor that regulates flagella production), HrpL (a sigma factor that regulates the T3SS), and AdrA, a GGDEF protein, affected both biofilm and cell morphology. Mutation of the cellulose synthase bcsA or of bcsC resulted in decreased accumulation of the T3SS-secreted protein HrpN.