cssi/SciSciGPT-SciSciNet huggingface dataset:
Trimethylsilylethynyl Ketones as Surrogates for Ethynyl Ketones in the Double Michael Reaction

Trimethylsilylethynyl ketones can be desilylated in the presence of a tethered carbon diacid and induced to undergo a double Michael reaction in situ. The trimethylsilylethynyl ketones can serve as surrogates of ethynyl ketones that are difficult to prepare or isolate.
Myeloid Progenitor Cells in the Premetastatic Lung Promote Metastases by Inducing Mesenchymal to Epithelial Transition

Tumors systemically initiate metastatic niches in distant target metastatic organs. These niches, comprised of bone marrow (BM)-derived hematopoietic cells, provide permissive conditions for future metastases. However, the mechanisms by which these cells mediate outgrowth of metastatic tumor cells are not completely known. Using mouse models of spontaneous breast cancer, we show enhanced recruitment of BM-derived CD11b+Gr1+ myeloid progenitor cells in the premetastatic lungs. Gene expression profiling revealed that the myeloid cells from metastatic lungs express versican, an extracellular matrix proteoglycan. Notably, versican in metastatic lungs was mainly contributed by the CD11b+Ly6Chigh monocytic fraction of the myeloid cells and not the tumor cells or other stromal cells. Versican knockdown in the BM significantly impaired lung metastases in vivo, without impacting their recruitment to the lungs or altering the immune microenvironment. Versican stimulated mesenchymal to epithelial transition (MET) of metastatic tumor cells by attenuating phospho-Smad2 levels, which resulted in elevated cell proliferation and accelerated metastases. Analysis of clinical specimens showed elevated versican expression within the metastatic lung of breast cancer patients. Together, our findings suggest that selectively targeting tumor elicited myeloid cells or versican represents a potential therapeutic strategy for combating metastatic disease.
Recording Interferometer for Precision Wave-Length Determinations*

A recording interferometer is described which permits the precise measurement of an angle by means of interferometric measurement of chord length. The present instrument, working in conjunction with a recording spectrometer, is applied to the problem of precise wave-length determinations. Preliminary results indicate that the average deviation of a single measurement is 0.044A. The application of this interferometer to the measurement of linear or rotational motion is discussed.
Treatment Options for Patients With Unresectable Colorectal Cancer With Wild-Type KRAS

KRAS mutation has been demonstrated to be an important marker which can be utilized to identify a subset of patients who will not benefit from, and may, in fact, be harmed by, treatment with anti- EGFR agents. The presence of an exon 2 KRAS mutation tells us not to use an anti-EGFR monoclonal antibody. A KRAS wild type result tells us that the option of using an anti-EGFR monoclonal antibody does exist, however it does not compel the use of these antibodies in first-line regimens. How and when to utilize the anti-EGFR agents in the management of patients with KRAS wild type tumors is the subject of this manuscript.
Occurrence of small colloids in sea water

COLLOIDAL particles in sea water may be important in the marine chemistry of elements such as carbon and iron1,2. Non-living, submicrometre particles (0.4–1.0 µm) have recently been found to be abundant (106–107 particles ml–1) in the north Pacific3 and off Nova Scotia4, but smaller colloidal particles in sea water remain largely uncharacterized. Here we report that marine colloids <120nm in size are at least three orders of magnitude more abundant than larger submicrometre particles. Moreover, the distribution with depth of these small colloids differs markedly from that reported for their larger counterparts3. This vertical stratification suggests that small colloidal particles in sea water are reactive. Examination by transmission electron microscopy and energy-dispersive X-ray spectroscopy indicates that the colloids are largely organic, although trace metals (Fe, Al, Co) may also be present. The existence of such colloids may contribute to the discrepancy between standard and new high-temperature methods for measuring dissolved organic carbon1.
"I Need Help!" Social Class and Children's Help-Seeking in Elementary School.

What role do children play in education and stratification? Are they merely passive recipients of unequal opportunities that schools and parents create for them? Or do they actively shape their own...
A reformulation of the maxmin expected utility model with application to agency theory

Abstract Invoking the parameterized distribution formulation of agency theory, the paper develops axiomatic foundations of the principal’s and agent’s choice behaviors that are representable by the maximization of the minimum expected utility over action-dependent sets of priors. In the context of this model, the paper also discusses some implications of ambiguity aversion for the design of optimal incentive schemes.
AGING AND COGNITION

Diminution of cognitive ability is so frequently observed in elderly people that the terms senescence (old age) and dementia are perceived as being virtually synonymous. Although intellectual decline does not invariably accompany aging, older people are certainly at greater risk in this respect. Important research carried out within the past three decades has demonstrated that "senile dementia" is always a consequence of serious illness and not simply a function of old age. More discrete cognitive impairments such as aphasia and amnesia are also common in older populations because the elderly are more vulnerable to the medical conditions that produce them. Apart from these illness-based cognitive impairments, however, less debilitating decrements in mental functioning are also observed in older individuals and appear to reflect the aging process itself. As increasing numbers of elderly patients seek neurologic consultation for deteriorating intellectual capacities, physicians must be cognizant of the full spectrum of aging-associated cognitive disorders. To that end, the following discussion focuses on acquired mental dysfunction in later life.
When Work-Family Support is Misallocated: The Key Role of Supervisor-Employee Value Congruence

To better manage our work demands and family demands, we often erect mental or physical “boundaries” to help manage our experiences. However, preferences for preserving these boundaries differ across individuals (e.g., some individuals may prefer to segment work/family roles, while others may prefer to integrate these roles) and employees may not always have similar preferences/values as their supervisors. We investigated the process through which employee-supervisor value congruence regarding boundary management strategies impacts work-family conflict (WFC) and job attitudes. We anticipated that value congruence would mitigate WFC through the receipt of family-supportive supervisor behavior (FSSB). We analyzed data from 815 staff members from four southern universities using PROCESS (Preacher & Hayes, 2008) and found that value congruence indirectly affects WFC, job satisfaction, and affective commitment through the mediating mechanism of FSSB.
Imaginal and verbal mnemonics as related to paired-associate learning and directionality of associations

Using a paradigm where unmixed paired-associate lists of concrete and abstract pairs were first learned followed by a mixed list of both pair types, concrete pairs were markedly superior to abstract pairs, but showed less improvement from unmixed to mixed lists. Subsequent recall tests showed superior forward over backward recall and more unidirectional recall (forward or backward but not both) for abstract than concrete pairs (which showed associative symmetry). Abstract-pair performance was better for subjects reporting more sentence mnemonics, but use of images was uncorrelated with concrete-pair performance. Recall also improved significantly with increased number of prior recall tests, which also produced more sentence mnemonics for abstract pairs but did not change mnemonic strategies for concrete pairs.
Why No Parties?: Investigating the Disappearance of Democrat-Whig Divisions in the Confederacy

The impact of political parties on political life in the United States has long been a subject of much interest to political scientists and other scholars. Works, beginning with Woodrow Wilson, Congressional Government: A Study in American Society (Baltimore: Johns Hopkins University Press, 1881), comprise a good many political science classics. Below I will refer to James L. Sundquist, Dynamics of the Party System: Alignment and Realignment of Political Parties in the United States (Washington, DC: Brookings, 1983); Gary W. Cox and Mathew D. McCubbins, Legislative Leviathan: Party Government in the House (Berkeley: University of California Press, 1993); John H. Aldrich, Why Parties?: The Origin and Transformation of Party Politics in America (Chicago: University of Chicago Press, 1995); and Sarah A. Binder, Minority Rights, Majority Rule: Partisanship and the Development of Congress (Cambridge: Cambridge University Press, 1997). In pursuit of a general theory of political parties, some scholars have focused on the origins of parties, believing that to understand their goals and actions, one must first understand why parties form. In particular, the rational-choice view of party formation has been the most prevalent view in recent years. John F. Hoadley, “The Emergence of Political Parties in Congress,” American Political Science Review 74 (1980): 757–79; John F. Hoadley, Origins of American Political Parties, 1789–1803 (Lexington: University of Kentucky Press, 1986); Joseph A. Schlesinger, Political Parties and the Winning of Office (Ann Arbor: University of Michigan Press, 1991); Joel H. Silbey, The American Political Nation, 1838–1893 (Stanford: Stanford University Press, 1991); John H. Aldrich and Ruth W. Grant, “The Antifederalists, the First Congress, and the First Parties,” Journal of Politics 55 (1993): 295–326; Aldrich, Why Parties?. To rational-choice scholars, parties are “endogenous” institutions, extralegal instruments created by political office seekers to further their goals and ambitions by solving various collective-action and social-choice problems. Thomas Schwartz, The Logic of Collective Choice (New York: Columbia University Press, 1986); Thomas Schwartz, “Why Parties?,” Research Memorandum, Department of Political Science, University of California at Los Angeles, 1989; Cox and McCubbins, Legislative Leviathan; Aldrich, Why Parties?. Stated another way, parties are a rational response by politicians to the complexities they face in the political world.
The Enumeration of Totally Symmetric Plane Partitions

Abstract A plane partition is totally symmetric if, as an order ideal of N 3 , it is invariant under all (six) permutations of the coordinate axes. We prove an explicit product formula for the number of totally symmetric plane partitions that fit in a cube of order n . This settles a conjecture published in 1980 by Andrews (who also attributed it to Macdonald and Stanley) and finishes the program of enumerating plane partitions belonging to each of the 10 symmetry classes proposed by Stanley in 1986. As a corollary of the proof, we also obtain a new proof of the formula, first obtained by Mills, Robbins, and Rumsey, for the number of plane partitions that are invariant under cyclic permutations and transposed complementation.
The influence of mechanical properties on wall stress and distensibility of the dilated ascending aorta

Abstract Objectives We sought to determine how intrinsic mechanical properties of dilated ascending aorta influence in vivo distensibility and wall stress, potential contributing factors to the risk of aortic rupture and dissection. Methods Fresh tissue from patients undergoing ascending aortic replacement for Marfan syndrome (n = 8, age 38 ± 14 years), bicuspid aortic valve with associated aneurysm (n = 20, age 55 ± 12 years), or idiopathic degenerative aneurysm (n = 7, age 64 ± 9 years) was analyzed for elastic properties and circumferential residual stress. Histologic specimens were graded for elastin fragmentation, cystic changes, fibrosis, and necrosis. Distensibility and wall stresses were predicted with a cylindrical mathematical model of the aorta. Results Elastic properties of aortic tissue were nonlinear and extensibility decreased with age. Moderate or severe elastin fragmentation was prevalent in tissue from patients with the Marfan syndrome and more common in tissue from younger patients. Model-predicted mean circumferential stress did not vary significantly with age or patient group, but increased with aortic lumen diameter and systolic blood pressure. Model-predicted distensibility decreased with age in bicuspid aortic valve and degenerative aneurysm groups. Differences in distensibility were correlated with differences in elastic properties. Conclusions The age dependence of elastic properties of dilated ascending aorta is consistent with that of normal aorta observed in previous studies. Increases in mean circumferential stress with blood pressure and diameter support the clinical importance of blood pressure control and serial evaluation of aortic diameter. Declining wall strength with age may increase the risk of rupture or dissection.
Toward Telemetry-driven Analytics for Understanding Players and their Avatars in Videogames

A great deal of research has gone into understanding the relationships between social behaviors, player preferences, and identities in both real-world and virtual environments. In this works-in-progress report, we describe AIRvatar, a tool that telemetrically collects data such as session-based time durations and click events during the process of avatar customization within a videogame of our own creation. We present results from a user-study of 181 players, highlighting how social phenomena such as gender-related stereotypes of users can be revealed, particularly when players' self-identified real world genders contrast with the gender identities of their avatars.
A better way to teach knot tying: a randomized controlled trial comparing the kinesthetic and traditional methods.

Abstract Background Knot tying is a fundamental and crucial surgical skill. We developed a kinesthetic pedagogical approach that increases precision and economy of motion by explicitly teaching suture-handling maneuvers and studied its effects on novice performance. Methods Seventy-four first-year medical students were randomized to learn knot tying via either the traditional or the novel "kinesthetic" method. After 1 week of independent practice, students were videotaped performing 4 tying tasks. Three raters scored deidentified videos using a validated visual analog scale. The groups were compared using analysis of covariance with practice knots as a covariate and visual analog scale score (range, 0 to 100) as the dependent variable. Partial eta-square was calculated to indicate effect size. Results Overall rater reliability was .92. The kinesthetic group scored significantly higher than the traditional group for individual tasks and overall, controlling for practice (all P P Conclusions For novices, emphasizing kinesthetic suture handling substantively improved performance on knot tying. We believe this effect can be extrapolated to more complex surgical skills.
APPROXIMATE POLYNOMIAL EXPANSION METHOD FOR INVERTING LAPLACE TRANSFORMS OF IMPULSE RESPONSES

We evaluate a method for inversion of Laplace transforms based on analytical expressions of temporal moments substituted into generalized Laguerre polynomial expansions. The moment expressions are derived from the Laplace transform of an impulse response function, a computation that can be performed by a symbolic manipulation computer program. Only the lower-order moments that contribute to the Poisson function are necessary for quite accurate approximations of heat and mass transfer, as well as chemical mixing and reaction problems, in the range of models between a stirred tank and a long column.
Ly-m11: the H-3 region of mouse chromosome 2 controls a new surface alloantigen.

Spleen cells from an SJL mouse immunized with 70'/3 cells, an established pre-B cell line, were fused with cells of the nonsecretor myeloma line NS.1. One established hybridoma cell line (clone K10.6) continuously secreted antibody that recognized a new antigenic specificity tentatively named Ly-m19. This newly found antigen is detectable on both T and B cells. Cytotoxicity assays reveal that 75 percent of the spleen and lymph-node cells, 35 percent of bone-marrow cells, and 15 percent of thymus cells reacted with antibody of clone K10.6. Strains expressing the specificity Ly-m19.1 are characterized by negative reactions and include the strains AKR, CE/J, RF/J, GR/A, SJL, P/J, BDP/J, and LG/J. All other strains so far tested are Ly-m19.2. This strain distribution pattern distinguishes Ly-m19 from any known murine lymphocyte alloantigen, but it parallels the Lyb-2c haplotype. Linkage test of a set of AKXL recombinant inbred strains revealed close linkage of Ly-m19 and Lyb-2 loci on mouse chromosome 4.
A Subspace Approach To Determining Sensor Gain And Phase With Applications To Array Processing

Exact characterization of the array in terms of its geometry and the sensor gain and phase is important in beamforming and directions-of-arrival estimation problems. In practice the sensor gain and phase may not be known exactly due to drift in the sensor characteristics. We present a subspace approach which uses the received array signals to estimate the sensor gain and phase. We assume that the directions-of-arrival of some of the several sources that impinge on the array are known and show how this information can be used to determine sensor parameters. The resulting estimates can then be used to improve the robustness of array processing algorithms both for directions-of-arrival estimation and beamforming. Results of simulations carried out to verify the performance of this method are presented.
Triaenophoriasis in Lake Erie white bass, Morone chrysops.

The pseudophyllidean tapeworm, Triaenophorus nodulosus, was found in 51% of the adult white bass, Morone chrysops, sampled from western Lake Erie during the summer of 1973. Prevalence of infection with Triaenophorus increased with size and age of fishes. This worm is responsible for the disease triaenophoriasis, which is grossly characterized by large, white cysts, dark-brown “streaks” and hemorrhages in the liver. Microscopically, there is an acute inflammatory response, necrosis of liver parenchyma, squamous metaplasia, fibrosis and displacement of liver tissue as the tapeworm grows. Many plerocercoids were necrotic and surrounded by a dense tissue. The pathophysiology of extensive liver obstruction needs to be investigated as well as its effect upon infected fish populations.
Formation and Crystallization of Yeast RNA Polymerase II Elongation Complexes

Minimal templates were devised for the efficient generation of yeast RNA polymerase II transcription elongation complexes. A 33-base pair DNA with a 15-residue dC tail at one 3'-end supported the formation of a complex containing the polymerase paused at nucleotide 11 of the duplex region and an RNA of 14-16 residues. The same template could yield an arrested complex with the enzyme at nucleotide 13-15 and RNA of 15-17 residues. These complexes were stable for at least a week under various conditions and could be resolved by gel electrophoresis or purified by ion exchange chromatography. The purified paused complex formed crystals capable of x-ray diffraction to 3.5 A resolution. The complex remained active in the crystal and, in the presence of nucleoside triphosphates, could efficiently extend the transcript in situ.
Reinitiation at the λ DNA origin accompanies the host SOS response

Abnormal reinitiation of replication from lambda origins has previously been found during infection in the presence of caffeine or cis-diamminedichloroplatinum II (cis-Pt) or when lambda infects a P2 lysogen. It was further shown that the reinitiations arising from cis-Pt treatment took place during the SOS response induced by the template damage caused by the drug. It is now shown that SOS induction by uv irradiation of the host also results in reinitiation events and that it is the SOS response itself rather than some other direct effect of the damaged host template that is responsible for the phenomenon. Parental sections of lambda replicative intermediates can supercoil, whereas daughter segments cannot. To explain the control that prevents reinitiation, it is proposed that normally the origin sequence has to be under superhelical tension to be a suitable substrate for the initiating machinery; once a round is in progress, the daughter origin sequences would not be under such tension and would therefore be inactive. It is shown that in an SOS environment the proposed requirement for a superhelical origin sequence is relaxed and consequently the control against reinitiation lost. Under such conditions, primary growing points that have encountered template lesions terminate and amore » new wave of replication initiates.« less
Neutron powder diffraction study of the superconducting quaternary intermetallic compound YNi2B2C

Abstract The crystal structure of YNi2B2C has been refined at room temperature using powder neutron diffraction data obtained from samples prepared by arc-melting. The nominal composition YNi3B2.5C yields a phase assemblage of principally 85 volume % YNi2B2C relative to Ni2B, and the YNi2.5B2C composition yields 93 volume % relative to 7 volume % Ni3B. YNi2B2C is apparently incongruently melting. The crystal structure is simply viewed as a “stuffed” derivative of the common layered ThCr2Si2-type structure, by inserting C atoms in the lanthanide (actinide) layer. Structural data for the most phase-pure title compound include: I4/mmm symmetry, a=3.5257(1) A , c=10.5336(4) A and x(B)=0.3589(4) . The atomic sites appear to be fully occupied, and there is no indication of B↔Ni disorder. The arc-melted YNi3B2.5C (nominal) sample has a superconducting Tc of 15.6 K, as defined by the onset of diamagnetism.
Other Teachers' Teaching: Understanding The Roles of Peer Group Collaboration in Teacher Reflection and Learning

Although most innovative professional development encourages reflective dialogue among teachers, we still know very little about how such dialogue enables teacher learning. This study describes how teachers make sense of the conflicts among their intended goals and actual practices by responding to their peers' teaching. Four teachers in a large urban high school each taught, evaluated, and shared four lessons they designed to enact self-identified goals absent from their practices. Patterns across the critiques, questions, compliments, and self-critiques that the teachers used to respond to others' lessons indicate the different ways they used the peer context to diversify, personalize, or slow down their thinking about their own teaching, and cross-case patterns reveal how they all learned in ways that would have been less likely in non-peer contexts. The findings suggest why diverse reflective peer groups are crucial starting points for larger professional networks designed to support systemic changes ...
Imaging studies in a unique familial dysmyelinating disorder

We report the imaging findings in five patients with a unique dysmyelinating disorder. MR studies of these infants showed obstructive hydrocephalus caused by mass effect produced by an enlarged cerebellum. The white matter of an enlarged cerebrum and cerebellum showed delayed myelination. Proton spectroscopy showed normal N-acetylaspartate (NAA) levels. While the dysmyelinating disorder was clearly differentiated from Canavan disease by an absence of elevated NAA and differing histopathologic findings and autosomal-dominant inheritance pattern, there were similarities to this disease in the presentation and, to some extent, in the initial imaging findings.
Long-Term Effects of Grazing and Haying on Soil Nutrient Dynamics in Forage-Based Beef Cattle Operations

ABSTRACT Nutrient levels over a 15-year period (1988–2002) were compared to evaluate the long-term effects of differing pasture management treatments (grazed-only or grazed and hayed) on soil phosphorus (P) and other crop nutrients (K, Ca, and K) in subtropical pastures planted with either bahiagrass (BG, Paspalum notatum Flugge) or rhizoma peanut (Arachis glabrata Benth)-mixed grass association (RP-G). Pasture management (P ≤ 0.001) significantly affected the levels of soil P and other crop nutrients. Mehlich-1 concentrations of P tended to be smaller (21%) in pasture fields that were both grazed and hayed than pasture fields that were grazed only. This may have occurred because hay removal lowered soil P levels. During the last 15 years (1988–2002), Mehlich-1 concentrations for P, K, Ca, Mg, and soil pH have declined by about 7, 38, 46, 61, and 23% in pastures with BG and 27, 55, 76, 56, and 22% for pasture fields with RP-G that were grazed in spring and hayed in early fall, respectively. Calcium appear...
Spatial Pattern of Uncertainties: An Accuracy Assessment of the TIGER Files

This study discusses the ways how the positional accuracy of the TIGER files can be measured and spatially reported. Many people and companies use the address range of the TIGER files with the geocoding package within a Geographic Information Systems (GIS). However, the problem is that many people have little understanding of the inaccuracy of the TIGER files. This study examines the relationships between the distribution of inaccuracy and physical factors such as stream and urbanity. Next, the inaccuracy of the hydrography shape file of TIGER 2000 files is calculated by comparing it with the stream points data of United States Geological Survey (USGS)’s Geographic Names Information System. Finally, this study examines whether there are individual patterns in each spatial data by comparing the spatial pattern of the inaccuracies of the road and hydrography shape file.
A carbon nanotube cortical neuron with spike-timing-dependent plasticity

This paper describes a carbon nanotube synapse circuit that exhibits Spike-Timing Dependant Plasticity (STDP). These synapses are found in cortical (e.g. pyramidal) neurons. Experiments with the synapse in a neuron circuit demonstrate changes in synaptic potential with pre- and post-spiking timing variations. The circuit design is biomimetic and changes in control voltages representing neurotransmitter concentration lead to changes in synaptic strength. The experiments are demonstrated with SPICE simulations using carbon nanotube transistor models.
The mechanics of dunes and antidunes in erodible-bed channels

An analytic model of free-surface flow over an erodible bed is developed and used to investigate the stability of the fluid-bed interface and the characteristics of the bed features. The model is based on the potential flow over a two-dimensional, moving, wavy bed with a sinusoidal profile of varying amplitude, and a sediment transport relation in which the transport rate is proportional to a power of the fluid velocity at the level of the bed. By assuming that the dominant wavelength is that for which the rate of amplitude growth is the greatest, expressions are obtained for the wavelength and velocity of the bed features. In addition, conditions for the occurrence of the different configurations, dunes, flat bed, and antidunes, are found from the model. The predicted wavelengths of antidunes and ranges of wavelengths of dunes, and the predicted conditions for change of bed configuration are found to be in good agreement with experimental data. Finally, brief consideration is given to the factors involved in determining the maximum heights of the bed features and surface waves.
Motherhood and Tenure: Can Catholic Universities Support Both?.

This paper presents a plan for the implementation of more family-friendly policies at Catholic colleges and universities, both as a matter of justice for women and on behalf of the well being of families. It is motivated by the teachings of the Catholic social tradition that emphasize the equality and dignity of women; the importance of the dual vocations of Christian parents, who are called to raise children and to work more publicly on behalf of the common good; and the inherent value of children and their right to be properly nutured and educated within the Christian family. Our starting point is the condition of families in the U.S. today as they struggle to thrive in spite of tremendous demands placed on parents who also work outside the home. We examine the negative effects on women and families that result from a refusal to accommodate parents with young children in the workplace. We are concerned in particular with the challenges faced by women academics at colleges and universities who are also mothers. We argue that, by and large, these women are not adequately supported in academia, even at Catholic universities, in spite of that tradition’s professed commitment to the health and well being of families. Finally we offer several concrete suggestions by which universities may better support women academics who are mothers, thereby contributing to the well being of women and families.
Single-Image Molecular Analysis for Accelerated Fluorescence Imaging

We have developed a new single-molecule fluorescence imaging analysis method, SIMA, that improves the temporal resolution of single-molecule localization and tracking studies to millisecond timescales without compromising the nanometer range spatial resolution [1,2,3,4]. In this method, the width of the fluorescence intensity profile of a static or a mobile molecule, imaged using submillisecond to milliseconds exposure time, is used for localization and dynamics analyses. We apply this method to three single-molecule investigations: (1) axial localization precision measurements, (2) subdiffraction molecular separation measurements, and (3) protein diffusion coefficient measurements in free solution.
Follow the Money: Who Benefits From the Federal Aviation Administration's DBE Program?

The Disadvantaged Business Enterprise (DBE) component of federal transportation programs creates important competitive advantages for firms considered to be socially and economically disadvantaged. Every recipient of federal transportation funds must set annual and contract goals targeting the DBE share of contract dollars. All firms owned by women and minorities are presumed to be socially disadvantaged and can become certified DBEs. DBE programs have been subject to legal and political controversy since they were enacted in 1982. This article is based on data of 5,385 contracts' worth $1.94 billion awarded by 423 recipients of the Federal Aviation Administrations fund in FY 2004. Findings show that race-conscious rather than race-neutral goals are predominantly used, that DBEs are greatly overutilized as subcontractors given the goals airports have set, and that the principal DBE group beneficiary of the awards is White women. Policy recommendations are offered.
The electrostatic field of an infinite array of cylinders

Infinite arrays of cylinders with square cross sections are analyzed using the method of field matching. By applying the method to the volume between the cylinder and the boundary of the cell, the electrostatic field in the volume can be determined. The results presented include the variation of the electrostatic field between the cylinders for various ratios of the half length of one side of the cylinder to the spacing between cylinders, the capacitance of the cylinders, and other characteristics. Various plots of the field are shown and are compared to the results of previous work. Some indication of the accuracy of the analysis is given. >
Expression of non-adrenergic imidazoline sites in rat cerebral cortical astrocytes.

Clonidine and related imidazoline agents, beside binding to α2-adrenergic receptors, have been shown to bind to a non-adrenergic site (imidazoline sites) in brain and peripheral tissues. However, which cell types in brain, namely neurons or glia, express this binding site and the cellular effects of activation of this site are not known. We investigated the cellular localization of imidazoline binding sites in cultured rat cortical astrocytes and neurons. Membranes prepared from cultured astrocytes showed specific, high affinity binding (KD: 4 nM) for 3H-idazoxan with about tenfold higher number of binding sites than α2-adrenergic sites (Bmax: 220 vs. 20 fmol/mg protein). Displacement studies exhibited the rank order of potency: cirazoline > idazoxan > amiloride > clonidine >>> epinephrine = ruawolscine defining this site as I-2a subtype of imidazoline binding sites. Moreover, the binding was inhibited by K+ but not by Na+, another characteristic of imidazoline binding sites. In contrast, membranes prepared from cultured neurons showed fewer binding sites for 3H-idazoxan that were completely displaced by adrenergic agents. Incubation of astrocytes with idazoxan, but not rauwolscine, resulted in a concentration-dependent increase in the levels of mRNA for the astrocyte specific molecule glial fibrillary acidic protein. We conclude that (a) the non-adrenergic imidazoline binding sites are expressed in astrocytes but not in neurons in rat cerebral cortex and (b) these “receptors” may influence astrocyte physiology by regulating the levels of GFAP. © 1993 Wiley-Liss, Inc.
Effect of Molting Method and Dietary Energy on Postmolt Performance of Two Strains of Single Comb White Leghorn Hens

SUMMARY This experiment was a 4 × 2 × 2 factorial arrangement of 4 dietary energy levels (2,767, 2,806, 2,846, and 2,886 kcal of ME/kg), 2 molting methods (feed withdrawal and the low-salt diet), and 2 strains (Bovans White and Dekalb White). The objective of this study was to determine the effect of dietary energy and molting method on postmolt performance of 2 strains of commercial White Leghorns. Before the molt, Bovans and Dekalb hens were randomly divided into 2 groups. Feed was withdrawn from half of the hens (66 wk of age) for 9 d. A molt feed was fed from d 10 to 28. The other half of the hens was fed a low-salt diet for 28 d. After the molt, Bovans White hens (n = 720) and Dekalb White hens (n = 720) at 70 wk of age were randomly divided into 16 treatments (6 replicates of 15 birds per treatment). Bovans hens had significantly lower egg weight, percent of eggshell, egg specific gravity, and Haugh units than Dekalb hens, whereas Bovans hens had significantly higher egg production than Dekalb hens. Increasing dietary energy had no significant effect on any parameter other than yolk color. As dietary energy increased, feed conversion improved numerically from 2.13 to 2.05, resulting in a 3.8% improvement of feed conversion. With increasing dietary energy, hens adjusted feed intake, according to egg mass, to achieve the quantities of dietary energy (5.8 to 5.9 kcal) intake per gram of egg. An ideal dietary energy level for optimal postmolt performance and profits could not be determined for hens during phase 1 of the second cycle. Other than slightly reduced egg production and egg specific gravity during phase 1, feeding the low-salt diet to induce molt could be used as an alternative for the conventional feed withdrawal method.
New Books across the Disciplines

"New Books across the Disciplines" is a bibliographic resource that facili- tates a cross-disciplinary survey of recent publications. Its scope ranges from late antiquity to the seventeenth century. Coverage is comprehensive for the large majority of North American and British publishers. Other European titles are included whenever received. Books are classified under variable topical headings and listed alphabetically by author's name. Entries include complete bibliographical data and annotations. Unless designated for paper- back editions, prices given are for cloth editions. For paperback reprint edi- tions, original publication dates are given in parentheses. With few excep- tions, books appearing here have been published within the previous two years. Many will be listed here before they are ordered and shelved by libraries.
Cross contamination of Escherichia coli O157:H7 between lettuce and wash water during home-scale washing

Lettuce and leafy greens have been implicated in multiple foodborne disease outbreaks. This study quantifies cross contamination between lettuce pieces in a small-scale home environment. A five-strain cocktail of relevant Escherichia coli O157:H7 strains was used. Bacterial transfer between single inoculated lettuce leaf pieces to 10 non-inoculated lettuce leaf pieces that were washed in a stainless steel bowl of water for 30 s, 1 min, 2 min, and 5 min was quantified. Regardless of washing time, the wash water became contaminated with 90-99% of bacteria originally present on the inoculated lettuce leaf piece. The E. coli O157:H7 concentration on initially inoculated leaf pieces was reduced ∼ 2 log CFU. Each initially uncontaminated lettuce leaf piece had ∼ 1% of the E. coli O157:H7 from the inoculated lettuce piece transferred to it after washing, with more transfer occurring during the shortest (30 s) and longest (5 min) wash times. In all cases the log percent transfer rates were essentially normally distributed. In all scenarios, most of the E. coli O157:H7 (90-99%) transferred from the inoculated lettuce pieces to the wash water. Washing with plain tap water reduces levels of E. coli O157:H7 on the inoculated lettuce leaf pieces, but also spreads contamination to previously uncontaminated leaf pieces.
Sexual and social competition: broadening perspectives by defining female roles.

Males figured more prominently than females in Darwin's view of sexual selection. He considered female choice of secondary importance to male–male competition as a mechanism to explain the evolution of male ornaments and armaments. Fisher later demonstrated the importance of female choice in driving male trait evolution, but his ideas were largely ignored for decades. As sexual selection came to embrace the notions of parent–offspring and sexual conflict, and experimental tests of female choice showed promise, females began to feature more prominently in the framework of sexual selection theory. Recent debate over this theory has centred around the role of females, not only over the question of choice, but also over female–female competition. Whereas some have called for expanding the sexual selection framework to encompass all forms of female–female competition, others have called for subsuming sexual selection within a broader framework of social selection, or replacing it altogether. Still others have argued for linking sexual selection more clearly to other evolutionary theories such as kin selection. Rather than simply debating terminology, we must take a broader view of the general processes that lead to trait evolution in both sexes by clearly defining the roles that females play in the process, and by focusing on intra- and inter-sexual interactions in males and females.
On the use of reset to increase the testability of interconnected finite-state machines

We propose a DFT solution for synchronous sequential circuits described as interconnections of finite-state machines, that takes into account specific requirements for justification of test sequences and propagation of fault effects occurring during test generation. We present this solution in the context of the output sequence justification problem. The proposed DFT solution is based on the use of reset. Three types of reset mechanisms are considered, having increasing overhead and increasing flexibility. The third type allows every output sequence over the output alphabet of a machine to be justified.
Biochemical Analysis of Neutral Endopeptidase Activity of the Cat Carotid Body

The carotid body contains enkephalins and tachykinins1–3. Several studies have shown that these peptides may be of importance in chemoreception3–6. Mechanisms that regulate the levels of these peptides in the carotid body have not been studied. Generally, neuropeptides are degraded by specific proteases7. The enzyme-neutral endopeptidase (also called enkephalinase (E.C.3.4.24.11)) is involved in the metabolism of ekephalins and tachykinins in the brain and kidney7,8.
Electronic transport properties of diamondoids

Abstract The electronic transport properties of diamantanes as a model of diamondoids (nanodiamonds) were studied by first-principles calculations. For this purpose, diamantane with thiol group was sandwiched between gold electrodes. Additionally, the effect of substitution of equatorial tertiary carbons on conductance was examined in detail. The conductance of boron- and phosphorus-substituted diamantanes was nearly the same as that of non-substituted diamantane, whereas the conductance of nitrogen-doped diamantane was higher. This is due to the fact that the nitrogen-substitution increases the transmittance at the Fermi level by the overlap of nitrogen 2p and sulfur 3s orbitals. Furthermore, the heteroatom-substituted diamantanes exhibited current rectification to a certain degree.
Self-assembled peptides for coating of active sulfur nanoparticles in lithium–sulfur battery

Development of lithium–sulfur (Li–S) battery is hindered by poor cyclability due to the loss of sulfur, although Li–S battery can provide high energy density. Coating of sulfur nanoparticles can help maintain active sulfur in the cathode of Li–S battery, and hence increase the cyclability. Among myriad of coating materials, synthetic peptides are very attractive because of their spontaneous self-assembly as well as electrical conductive characteristics. In this study, we explored the use of various synthetic peptides as a coating material for sulfur nanoparticles. Atomistic simulations were carried out to identify optimal peptide structure and density for coating sulfur nanoparticles. Three different peptide models, poly-proline, poly(leucine–lysine) and poly-histidine, are selected for this study based on their peptide–peptide and peptide-sulfur interactions. Simulation results show that both poly-proline and poly(leucine–lysine) can form self-assembled coating on sulfur nanoparticles (2–20 nm) in pyrrolidinone, a commonly used solvent for cathode slurry. We also studied the structural integrity of these synthetic peptides in organic [dioxolane (DOL) and dimethoxyethane (DME)] electrolyte used in Li–S battery. Both peptides show stable structures in organic electrolyte (DOL/DME) used in Li–S battery. Furthermore, the dissolution of sulfur molecules in organic electrolyte is investigated in the absence and presence of these peptide coatings. It was found that only poly(leucine–lysine)-based peptide can most effectively suppress the sulfur loss in electrolyte, suggesting its potential applications in Li–S battery as a coating material.
High-order strand grid methods for shock turbulence interaction

ABSTRACTIn this work, we examine the flux correction method for three-dimensional transonic turbulent flows on strand grids. Building upon previous work, we treat flux derivatives along strands with high-order summation-by-parts operators and penalty-based boundary conditions. A finite-volume like limiting strategy is implemented in the flux correction algorithm in order to sharply capture shocks. To achieve turbulence closure in the Reynolds-Averaged Navier–Stokes equations, a robust version of the Spalart–Allmaras turbulence model is employed that accommodates negative values of the turbulence working variable. Validation studies are considered which demonstrate the flux correction method achieves a high degree of accuracy for turbulent shock interaction flows.
Classroom Experiments: Is More More?

Studies have demonstrated that classroom experiments have a positive effect on student achievement in economics courses. Questions remain regarding the appropriate number of experiments. In the current study we attempt to determine whether more intensive use of classroom experiments is associated with greater student achievement. Our data contains variation in the number of experiments administered in a principles of microeconomics course. We find that participation in classroom experiments has a positive, but diminishing, marginal benefit on students' final course scores. We also find that classroom experiments can bridge some achievement gaps (between older and younger students, between whites and minorities).
Discussion about the application of sample size in the prediction of disease using GM (1,1) model

Objective To explore the suitable number of samples by using GM( 1,1) model to build predictive mode.Methods According to the incidence of hepatitis A,syphilis and Japanese Encephalitis in Hubei province from 1991 to2011,the consecutive data of 4 years and 10 years respectively were extracted to build the model and make the prediction.There after,the modeling and forecast accuracy were analyzed and compared. Results The comparison of the number of different samples showed that the success rate of fitting between hepatitis A and syphilis was of no significant difference,while there was significant difference with JE,the absolute percentage error and success rate of forecast among the three diseases showed no significant difference. Conclusions It is advisable to use the smallest possible sample size,when the original data change showed a regular exponential change. However,when the index variation characteristics of the original data fluctuated,a sufficient number of samples should be collected until it could fully express the index variation.
The Well-bottom Fluid Field Analysis of One-cone Bit

It is testified by many facts that single nozzle and dual nozzles have a good clean effect. We study some kinds that are often used. In order to find out the best kind, we can give some good advice to the water system design of one-cone bit.
Phase contrast x-ray imaging signatures for homeland security applications

Gratings-based phase contrast imaging is a promising new radiographic technique providing three distinct contrast mechanisms, absorption, phase, and scatter, using a conventional x-ray tube source. We investigate the signatures available in these three contrast mechanisms with particular attention towards potential homeland security applications. We find that the scatter mode in particular is sensitive to textured materials, enabling lowered detection limits than absorption for materials such as powders. We investigate the length scales to which our imaging system is sensitive.
Thermodynamic Additivity for Impacts of Base-Pair Substitutions on Association of the Egr-1 Zinc-Finger Protein with DNA.

The transcription factor Egr-1 specifically binds as a monomer to its 9 bp target DNA sequence, GCGTGGGCG, via three zinc fingers and plays important roles in the brain and cardiovascular systems. Using fluorescence-based competitive binding assays, we systematically analyzed the impacts of all possible single-nucleotide substitutions in the target DNA sequence and determined the change in binding free energy for each. Then, we measured the changes in binding free energy for sequences with multiple substitutions and compared them with the sum of the changes in binding free energy for each constituent single substitution. For the DNA variants with two or three nucleotide substitutions in the target sequence, we found excellent agreement between the measured and predicted changes in binding free energy. Interestingly, however, we found that this thermodynamic additivity broke down with a larger number of substitutions. For DNA sequences with four or more substitutions, the measured changes in binding free e...