cssi/SciSciGPT-SciSciNet huggingface dataset:
DNA repair and transcription

The transcription factor TFIIH continues to be a subject of interest. In addition to its function as a repair and transcription factor, TFIIH includes a cyclin-dependent kinase and a cyclin, which raises the possibility that nucleotide excision repair (NER), RNA polymerase II transcription and cell cycle control are connected. Progress in mechanistic studies of NER include the identification of dual incision activities operating on either side of base damage and the isolation of a repairosome supercomplex in yeast. Additionally, NER has been demonstrated in reconstituted human and yeast systems, both of which include TFIIH.
Competitive Consecutive Electron Transfer in Determination of Ionization Potentials: Ketene Derivatives

Kinetics of competitive consecutive electron transfer was used to determine ionization potentials of transient species. Kinetics of two-stage electron transfer reactions in aprotic solvent was studied using 355 nm laser flash photolysis. The concentrations of transients produced by the laser flash photolysis were monitored by their light absorption. Triplet-excited tetrachloro-p-benzo-quinone (p-chloranil) generated by a 355 nm laser flash oxidized diethyl ketene, diphenyl ketene, or phenyl ethyl ketene to form radical cations. The ketene radical cations, in turn, oxidized tertiary amine, forming ground state ketene and ammonium radical cation. The kinetics of the disappearance of ketene radical cations (and/or appearance of ammonium radical cations) due to consecutive, competitive electron transfer to ketene and p-chloranil radical cations was monitored. By monitoring kinetics in the presence of tertiary amines with different oxidation potentials, it was established that in acetonitrile the oxidation potential of diethyl ketene was 5.4 eV; for phenyl ethyl ketene, it was approximately 4.8 eV; and for diphenyl ketene, it was 4.6 eV. The results were in agreement with the oxidation potentials of ketenes computed using published data.
Predicting weather and climate: Uncertainty, ensembles and probability

Abstract Simulation-based weather and climate prediction now involves the use of methods that reflect a deep concern with uncertainty. These methods, known as ensemble prediction methods, produce multiple simulations for predictive periods of interest, using different initial conditions, parameter values and/or model structures. This paper provides a non-technical overview of current ensemble methods and considers how the results of studies employing these methods should be interpreted, paying special attention to probabilistic interpretations. A key conclusion is that, while complicated inductive arguments might be given for the trustworthiness of probabilistic weather forecasts obtained from ensemble studies, analogous arguments are out of reach in the case of long-term climate prediction. In light of this, the paper considers how predictive uncertainty should be conveyed to decision makers.
Temperature dependence of tracer diffusion coefficients in polystyrene

The temperature dependence of the tracer diffusion coefficient D* of long deuterated polystyrene (d-PS) chains of molecular weight M>Mc, where Mc is the critical molecular weight for entanglement, diffusing into highly entangled PS matrices, each of molecular weight P = 2×107, is studied using forward recoil spectrometry. It is found that the temperature dependence of D*/T, reflected primarily in the monomeric friction coefficient, is accurately described by a Vogel equation. The constants that are used to fit these results are independent of M and are the same as those used to fit the temperature dependence of the zero shear rate viscosity of polystyrene.
Wallace Coulter's life and his impact on the world

2013 is the centenary of Wallace Coulter's birth. He was an engineer, inventor, entrepreneur and visionary. He transformed the practice of laboratory hematology with his invention of the Coulter Principle and its application to blood cell analysis, together with the company he founded to bring it and his subsequent inventions and innovations to the world. He was born in modest circumstances and he remained modest in his outlook on life, despite his magnificent achievements, his successes, his numerous prestigious awards and his wealth later in life. This article traces his early life, his career, his achievements and the immense benefits he brought to the people of this planet.
Talcott Parsons: The social relations of individualism and economy

Abstract Talcott Parsons' critique of utilitarian individualism, possessive forms of property and contract, and instrumentalism provides grounds for a relational and nonreductive analysis of individualism and economy. Rather than defining individualism and economic action through possessions and market relations, individuals and such core economic categories as property, wealth, contract, and profit are established through differentiating social processes, interactions among institutions, and integrative norms and values. Instead of leading to atomism, overdetermination, or an exogenous overlay of norms on instrumental rationality, relational and reflective dimensions of concepts for the analysis of economic action are paramount. A critical appropriation of these concepts provides an expansive view of individualism and economic action, emphasizing the integration of economic and noneconomic factors in shaping economic action. The paper concludes by illustrating these themes empirically.
Right and left dorsolateral pre-frontal rTMS treatment of refractory depression: A randomized, sham-controlled trial

We conducted a prospective, randomized, sham-controlled, double blind, parallel group study of right or left pre-frontal rTMS in 48 subjects with medication-resistant depression. Two thousand (50x8-s trains of 5Hz) stimuli at MEP threshold were delivered each weekday for 2weeks. We employed a sham coil and simultaneous electrical stimulation of the scalp to simulate rTMS. Mean (+/-S.D.) reductions in the HAMD-24 from baseline to 3-months were not significantly different between rTMS and sham treatment groups. However, right cranial stimulation (sham or rTMS) was significantly more effective than left cranial stimulation (sham or rTMS) (P=0.012). Mean (+/-S.D.) reductions in the HAMD from baseline to 3 months were: left: 28.1 (+/-5.36) to 19.2 (+/-11.2); and right 27.2 (+/-4.2) to 11.5 (+/-9.4). Left rTMS achieved a reduction in HAMD 9.5 points greater than that achieved by left sham, a benefit greater than that reported in a recent multi-center Phase III trial of rTMS (O'Reardon et al., 2007), albeit not statistically significant. These results suggest that somatosensory stimuli that repeatedly engage the left hemisphere may be important to the achievement of therapeutic effect.
Political Skill at Work

The article reviews the book “Political Skill at Work,” by Gerald R. Ferris, Sherry L. Davidson and Pamela L. Perrewe.
NSAIDs inhibit the activation of egr-1 gene in microvascular endothelial cells. A key to inhibition of angiogenesis?

Nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin, indomethacin (IND), ibuprofen and newer cyclooxygenase-2 selective NSAIDs (e.g. celecoxib) delay gastric ulcer healing partly through the inhibition of angiogenesis, but the molecular mechanisms involved are not fully elucidated. Effective angiogenesis is required for ulcer healing to supply oxygen and nutrients to the healing site. The early growth response factor (Egr-1) is a transcription factor, which is rapidly activated by a variety of extracellular signals or tissue injury and is important for angiogenesis to occur. This study aimed to determine whether indomethacin (IND) and/or the selective COX-2 inhibitor, NS-398, interfere with egr-1 gene expression in human microvascular endothelial cells (HMVEC) in response to vascular endothelial growth factor (VEGF) stimulation. HMVEC were treated with 0.5 mM IND or 100 μM NS-398 for 16 h, and then VEGF (10 ng/ml) or vehicle was added. Egr-1 mRNA and protein expression levels were determined by RT-PCR and Western-blotting, respectively. VEGF treatment caused a significant elevation of Egr-1 mRNA (261±21%, P<0.001) and protein expression (174±15%, P<0.01) vs. vehicle. IND pre-treatment significantly inhibited VEGF-induced Egr-1 mRNA expression by 29±4% (P<0.01) and protein expression by 41±8% (P<0.05). NS-398 inhibited VEGF-induced Egr-1 mRNA and protein expression by 23±3% and 35±4%, respectively (both P<0.01). Since trancriptional activation of egr-1 is responsible for expression of proteins involved in proliferation of endothelial cells essential for angiogenesis, these results provide a new mechanism for NSAIDs' interference with angiogenesis.
Do parental cash transfers weaken performance in college

Abstract When parents support children in college, does this undermine the incentive to do well? The authors test the hypothesis that parental cash transfers induce college students to commit moral hazard in their studies on a sample of nearly 1300 undergraduates at two Midwestern universities. After controlling for a wide variety of factors influencing college performance, it was found that those students receiving at least partial coverage from their parents for tuition and books: (1) failed their courses more often than self-financed students; (2) were at higher risk of being placed on academic probation; and (3) earned lower GPAs.
ASSESSING REPOSITORY TECHNOLOGY: WHERE DO WE GO FROM HERE?

Three sample information retrieval systems, archie, autoLib, and Wide Area Information Service (WAIS), are compared with regard to their expressiveness and usefulness, first in the general context of information retrieval, and then as perspective software reuse repositories. While the representational capabilities of these systems are limited, they provide a useful foundation for future repository efforts, particularly from the perspective of repository distribution and coherent user interface design.
Use of sphere phantoms to measure the 3D MTF of FDK reconstructions

To assess the resolution performance of modern CT scanners, a method to measure the 3D MTF is needed. Computationally, a point object is an ideal test phantom but is difficult to apply experimentally. Recently, Thornton et al. described a method to measure the directional MTF using a sphere phantom. We tested this method for FDK reconstructions by simulating a sphere and a point object centered at (0.01 cm , 0.01 cm, 0.01 cm) and (0.01 cm, 0.01 cm, 10.01 cm) and compared the directional MTF estimated from the reconstructed sphere with that measured from an ideal point object. While the estimated MTF from the sphere centered at (0.01 cm , 0.01 cm, 0.01 cm) showed excellent agreement with that from the point object, the estimated MTF from a sphere centered at (0.01 cm , 0.01 cm, 10.01 cm) had significant errors, especially along the fz axis. We found that this is caused by the long tails of the impulse response of the FDK reconstruction far off the central plane. We developed and tested a new method to estimate the directional MTF using the sphere data. The new method showed excellent agreement with the MTF from an ideal point object. Caution should be used when applying the original method in cases where the impulse response may be wide.
Supporting change through local action

To improve current civil society and achieve the possibilities globalization offers, we must incorporate an education-for-empowerment approach to lifelong learning. This chapter explores the potential, promise, and implications for local action and dialogue.
High-Pressure Vapor−Liquid Equilibrium for Dimethyl Ether + 2-Propanol and Dimethyl Ether + 2-Propanol + Water

We report vapor−liquid equilibrium data for the system dimethyl ether (DME) + 2-propanol at 323.45, 348.45, and 373.45 K and for the system dimethyl ether + 2-propanol + water at 323.25, 348.05, and 373.15 K. The experimental data are correlated using the Peng−Robinson equation of state and the Elliott−Suresh−Donohue equation of state. We explore the properties of dimethyl ether in the ternary system as a near-critical or supercritical solvent or cosolvent. The data for the dimethyl ether solutions are compared to literature data for ternary systems containing propylene or propane + 2-propanol + water. Dimethyl ether exhibits relatively higher solubility in the aqueous phase, leading to enhanced volatility of water at relatively low pressures compared to the case for propane. On the other hand, dimethyl ether also becomes completely soluble in the aqueous solution at relatively low pressures, precluding two-phase mass transfer under certain conditions.
High survival of mouse oocytes/embryos after vitrification without permeating cryoprotectants followed by ultra-rapid warming with an IR laser pulse

Vitrification is now the main route to the cryopreservation of human and animal oocytes and preimplantation embryos. A central belief is that for success, the cells must be placed in very high concentrations of cryoprotective solutes and must be cooled extremely rapidly. We have shown recently that these beliefs are incorrect. Over 90% of mouse oocytes and embryos survive being cooled relatively slowly even in solutions containing only 1/3(rd) the normal solute concentrations, provided that they are warmed ultra-rapidly at 10(7)°C/min by a laser pulse. Nearly all vitrification solutions contain both permeating and non-permeating solutes, and an important question is whether the former protect because they permeate the cells and promote intracellular vitrification (as is almost universally believed), or because they osmotically withdraw a large fraction of intracellular water prior to cooling. The answer for the mouse system is clearly the latter. When oocytes or embryos are placed in 1 molal concentrations of the impermeable solute sucrose, they osmotically lose ~85% of their cellular water in less than 2 minutes. If the cells are then cooled rapidly to -196°C, nearly 90% remain viable after warming, again provided that the warming is ultra rapid.
Coagulation changes in individuals with sickle cell trait.

Sickle cell disorders, such as Hb SS and Hb SC, are associated with a hypercoagulable state that may contribute to the vaso-occlusive episodes observed in the disorders. To what extent increased coagulation activity occurs in individuals with sickle cell trait has had limited study. Because such information may help clarify clinical and pathologic findings that may occur in these individuals and may be useful in clarifying the hypercoagulable state in sickle cell disease, we have examined individuals with Hb AS to determine the extent that increased coagulation activity does occur. We measured d-dimers, thrombin-antithrombin (TAT) complexes, prothrombin fragment 1.2 (F1.2), absolute blood monocyte levels, proteins C and S, and isotypes of antiphospholipid antibodies in individuals with Hb AS and in matched controls (Hb AA). Results showed that d-dimers, TAT, and F1.2 were increased significantly above normal levels. Absolute blood monocyte levels were increased. The d-dimers, TAT, F1.2, and monocyte counts showed significant increasing trends through groups of increasing severity (Hb AA, Hb AS, Hb SC, and Hb SS). Our study shows that individuals with Hb AS have increased coagulation activity, with d-dimers, TAT, and F1.2 being consistent indicators. The measures of coagulation activity in Hb AS are lower than in patients with Hb SC and Hb SS disease. These results extend our previous observation that the degree of coagulation activation parallels the degree of disease severity among sickle cell genotypes. The findings suggest that monocytosis, with the possible expression of monocyte-derived tissue factor, and the associated hypercoagulable state are driven by disease severity.
Novel THz imaging array using high resistivity metasurfaces

In this paper, lossy metasurfaces are employed in the design of uncooled terahertz (THz) bolometers on polymer substrate. The metasurface bolometer is composed of a metal backed low loss dielectric substrate and thin patterned lossy metal layer. Numerical simulations using finite element method (FEM) are carried out to design optimal unit cells with high absorptivity. An array of these unit cells are combined together to form a pixel element of an imaging array. Unit cells with center frequency of 0.1 and 0.4 THz are designed. A 3×3 imaging array operating at 0.1THz is fabricated on a plastic substrate and measured results are presented. An image of a concealed object inside a paper envelope is also demonstrated in transmission mode using this array. Results show that high sensitivity THz bolometers can be fabricated on low-cost substrates using strongly absorbing metasurfaces.
Level of automation and failure frequency effects on simulated lunar lander performance

A human-in-the-loop experiment was conducted at the NASA Ames Research Center Vertical Motion Simulator, where instrument-rated pilots completed a simulated terminal descent phase of a lunar landing. Ten pilots participated in a 2 x 2 mixed design experiment, with level of automation as the within-subjects factor and failure frequency as the between-subjects factor. The two evaluated levels of automation were high (fully automated landing) and low (manual controlled landing). During test trials, participants were exposed to either a high number of failures (75% failure frequency) or low number of failures (25% failure frequency). In order to investigate the pilots' sensitivity to changes in levels of automation and failure frequency, the dependent measure selected for this experiment was accuracy of failure diagnosis, from which D Prime and Decision Criterion were derived. For each of the dependent measures, no significant difference was found for level of automation and no significant interaction was detected between level of automation and failure frequency. A significant effect was identified for failure frequency suggesting failure frequency has a significant effect on pilots' sensitivity to failure detection and diagnosis. Participants were more likely to correctly identify and diagnose failures if they experienced the higher levels of failures, regardless of level of automation.
The medial accessory nucleus of bechterew: A cell group within the anatomical limits of the rostral oculomotor complex receives a direct prefrontal projection in the monkey

The medial accessory nucleus of Bechterew, a vertically oriented cell group in the rostral lateral oculomotor nucleus (OMN), contiguous dorsally with the nucleus of Darkschewitsch (ND) and ventrally with the parvocellular red nucleus, is separated from the interstitial nucleus of Cajal (IC) by a small paraoculomotor fascicle (POF) that forms the anatomical limits of the OMN. Horseradish peroxidase (HRP) gel implants in the prearcuate frontal cortex dorsal to the caudal third of the principal sulcus in the monkey resulted in an anterogradely labeled bilateral projection to this paraoculomotor cell group. The functional role of this largely overlooked nucleus is yet to be determined. However, the failure to retrogradely label following HRP injections involving both the extraocular muscles and ciliary ganglion suggests that it cannot be classified as belonging to either the somatic or the visceral cell column at the present time. We suggest that, like IC and ND, it probably contributes to the POF of the medial longitudinal fasciculus and may be involved in internuclear connections. There is little doubt that it has been involved inadvertently in studies of oculomotor connections.
The effect of trifluoperazine, a calmodulin antagonist, on the growth of normal and malignant epidermal keratinocytes in culture

Calmodulin, a cytoplasmic calcium binding protein, is present in concentrations two- to four-fold higher in malignant cells compared to normal cells. In an effort to learn the significance of these elevated levels, we examined the effect of calmodulin blockage on the growth of normal and malignant keratinocytes in vitro. The level of calmodulin in SCC12.B2, a line of keratinocytes derived from an epidermal squamous cell carcinoma (SCC), was about 3.5 times greater than in normal, human newborn foreskin keratinocytes. When exposed to trifluoperazine (TFP), an inhibitor of calmodulin, cell growth was reduced primarily in the cultures of normal keratinocytes. This growth inhibition resulted from two changes in the replicating population of cells, namely an increase in cell cycle length and an increase in rate of cell cycle withdrawal. Cell cycle withdrawal is the irreversible arrest of the cell cycle and is an early event in keratinocyte terminal differentiation. There was no measurable effect on the cell cycle time or withdrawal rate in SCC12.B2. The increased resistance to growth arrest in SCC cells may be a consequence of the elevated level of calmodulin in these cells.
Evolution of the Cluster Mass and Correlation Functions in a ΛCDM Cosmology

The evolution of the cluster mass function and the cluster correlation function from z = 0 to 3 is determined using ~106 clusters obtained from high-resolution simulations of the current best-fit ?CDM cosmology (?m = 0.27, ?8 = 0.84, h = 0.7). The results provide predictions for comparisons with future observations of high-redshift clusters. A comparison of the predicted mass function of low-redshift clusters with observations from early Sloan Digital Sky Survey data and the predicted abundance of massive distant clusters with observational results favor a slightly larger amplitude of mass fluctuations (?8 ~ 0.9) and lower density parameter (?m ~ 0.2); these values are consistent within 1 ? with the current observational and model uncertainties. The cluster correlation function strength increases with redshift for a given mass limit; the clusters were more strongly correlated in the past because of their increasing bias with redshift?the bias reaches b ~ 100 at z = 2 for M > 5 ? 1013 h-1 M? clusters. The richness-dependent cluster correlation function, represented by the correlation scale versus cluster mean separation relation, R0-d, is generally consistent with observations. This relation can be approximated as R0 = 1.7d0.6 h-1 Mpc for d ~ 20-60 h-1 Mpc. The R0-d relation exhibits surprisingly little evolution with redshift for z < 2; this finding can provide a new test of the current ?CDM model when compared with future observations of high-redshift clusters.
Regulation of immune responses of the intestinal mucosa

The largest lymphoid organ in the body, the intestine, is also the most intriguing and complex. At its root, the gastrointestinal immune system must permit the absorption of nutrients while protecting against invasion of pathogens. In the process, it must sort through vast antigenic challenges and orchestrate an immune response appropriate to the occasion. Whereas the general outline of mucosal immunity has been defined with respect to the phenotype of the immune cells that compose the mucosal immune system, the ontogeny of these immune cells, and the regulation of IgA responses, the details that control mucosal T cell activation and suppression that coordinate this elaborate mucosal network continue to perplex. This review highlights unique aspects of T cell regulation within the intraepithelial lymphocyte (IEL) and lamina propria lymphocyte (LPL) compartments when compared with lymphocytes in the periphery. In general, IEL are largely extrathymically derived, have a limited TCR repertoire capable of recognizing common microbiologic Ags, and demonstrate predominantly cytolytic functions. LPL are thymically derived, highly activated lymphocytes with predominantly Th2 phenotype. LPL activation is distinct from classic memory T cells in their CD2/CD28 predominance that likely contributes to limiting TCR/CD3-mediated signals in the mucosa. Ag presentation in the gut may involve nonclassical, nonpolymorphic class I-like molecules expressed by epithelial cells that may positively select extrathymically derived lymphocyte populations as well as tolerize self-reactive lymphocytes. These special features of the mucosal immune system are integrated to downregulate immune responses to ubiquitous lumenal Ags.
Freshwater fungi: Fossil record and paleoecological potential

Abstract Representatives of most major groups of fungi occur in lakes or streams, either parasitizing other aquatic organisms or living as saprophytes on autochthonous or allochthonous organic matter. Aquatic fungi are of considerable importance in the population dynamics of plankton and in nutrient cycling via the detritus food chain. A brief survey of the classification of living freshwater fungi is presented. The simple structure of many living phycomycetes, coupled with a classification system which relies on developmental criteria and the flagellation of ephemeral zoospores, makes interpretation of fossil forms difficult. Unambiguous published fossil records of freshwater fungi are few: Chytridiomycete sporangia on plant spores and scars on pollen thought to have been produced by water molds, phycomycetous hyphae, and spores of aquatic hyphomycetes. Helicoon and Casaresia are reported from the Miocene of the Pacific Northwest. Quilonia is reinterpreted as a tetraradiate aquatic spore. The potential of fungal remains in paleolimnological investigations is considerable. Parasitic forms, which should be sought on their hosts, offer clues concerning the evolution of host/parasite relationships through time and amplify understanding of host population dynamics. Allochthonous fungal spores are a promising source of information concerning the surrounding watershed. Interpretation of fossil data is hampered by a lack of equivalent studies of fungal populations in modern lakes.
Design and fabrication of electrostatic actuators with corrugated membranes for MEMS deformable mirror in space

A novel Microelectromechanical Systems (MEMS) deformable mirror technology for large, lightweight, segmented space telescopes is being proposed.
An Overview Of Cardiovascular Disease Burden In The United States

Cardiovascular disease (CVD) is the leading cause of death and a major cause of disability worldwide. In the United States, CVD accounted for 34.4 percent of the 2.4 million deaths in 2003 and rema...
Trends in power semiconductor devices

This paper reviews recent trends in power semiconductor device technology that are leading to improvements in power losses for power electronic systems. In the case of low voltage ( 100 V) power rectifiers, the silicon P-i-N rectifier continues to dominate but significant improvements are expected by the introduction of the silicon MPS rectifier followed by the GaAs and SiC based Schottky rectifiers. Equally important developments are occurring in power switch technology. The silicon bipolar power transistor has been displaced by silicon power MOSFETs in low voltage ( 100 V) systems. The process technology for these MOS-gated devices has shifted from V-MOS in the early 1970s to DMOS in the 1980s, with more recent introduction of the UMOS technology in the 1990s. For the very high power systems, the thyristor and GTO continue to dominate, but significant effort is underway to develop MOS-gated thyristors (MCTs, ESTs, DG-BRTs) to replace them before the turn of the century. Beyond that time frame, it is projected that silicon carbide based switches will begin to displace these silicon devices.
A framework for the organization and discovery of information resources in a www environment using association, classification and deduction

The Semantic Web is envisioned as a next-generation WWW environment in which information is given well-defined meaning. Although the standards for the Semantic Web are being established, it is as yet unclear how the Semantic Web will allow information resources to be effectively organized and discovered in an automated fashion. This dissertation research explores the organization and discovery of resources for the Semantic Web. It assumes that resources on the Semantic Web will be retrieved based on metadata and ontologies that will provide an effective basis for automated deduction. An integrated deduction system based on the Resource Description Framework (RDF), the DARPA Agent Markup Language (DAML) and description logic (DL) was built. A case study was conducted to study the system effectiveness in retrieving resources in a large Web resource collection. The results showed that deduction has an overall positive impact on the retrieval of the collection over the defined queries. The greatest positive impact occurred when precision was perfect with no decrease in recall. The sensitivity analysis was conducted over properties of resources, subject categories, query expressions and relevance judgment in observing their relationships with the retrieval performance. The results highlight both the potentials and various issues in applying deduction over metadata and ontologies. Further investigation will be required for additional improvement. The factors that can contribute to degraded performance were identified and addressed. Some guidelines were developed based on the lessons learned from the case study for the development of Semantic Web data and systems.
Sentinel lymph node dissection is technically feasible in older breast cancer patients

Abstract Background Previous studies suggested that sentinel lymph node (SLN) identification rates are lower in older breast cancer patients. This study was undertaken to compare identification rates in patients 70 years of age and older versus those younger than 70 years in a large cohort undergoing sentinel lymph node dissection (SLND). Study Design: Patients undergoing SLND between August 1993 and December 2006 were identified and grouped by age. Clinicopathologic data and details regarding the procedure were reviewed. Results: Of the 3995 patients undergoing SLND, 3406 (85.3%) were under 70 years of age, and 589 (14.7%) were 70 years or older. Age was significantly associated with clinical stage ( P = .001) and tumor grade ( P P = .01). Conclusion: Sentinel lymph node dissection can be performed with high identification rates regardless of patient age. Breast cancer patients 70 years and older with clinically negative axillary lymph nodes should be offered SLND, as the presence of lymph node metastasis may alter adjuvant therapy recommendations.
Effects of Porcelain/Alloy Interfacial Diffusion Zones on Thermo-mechanical Strain

Chemical bonding between dental porcelains and alloys results from interdiffusion of porcelain and metal ions. An interfacial diffusion zone is created which, most likely, has properties different from those of bulk materials. The changed interface might affect experimental measurements of thermo-mechanical strain. To determine the magnitude and conditions under which this would occur, the interface was modeled as the intermediate layer of a three-layered porcelain-veneered split-metal ring. Layer thicknesses and coefficients of thermal expansion were varied, and the effects on gap change after cooling through 500 degrees C were calculated. Results are presented in a series of 14 Figs., ten curves each, which depict not only interfacial effects, but are extended for use in interpretation of the effects of properties of opaques and glazes as well. Under most conditions, the interface will not affect experimental measurements; some special exceptions are noted.
Sidelobe reduction for matched filter range processing

Linear frequency modulation (LFM) matched filtering results in range sidelobes. These sidelobes are often objectionable because they may mask small targets or may be mistaken for targets themselves. Various methods of sidelobe control are investigated and their performance is measured. The methods of sidelobe reduction include dual apodization, spatially variant apodization, and leakage energy minimization. Nonlinear frequency modulation (NLFM) matched filtering is also investigated. A simulation was run to compare LFM with sidelobe control and NLFM, all using moderately low pulse compression ratios. Results suggest that generally, NLFM matched filtering has better detection and estimation characteristics than LFM with sidelobe control.
The journal communication system for MIS research

Journals constituting the formal communication system for Management Information System (MIS) research are described and analyzed. Six measures of journal importance in communicating MIS research are developed based upon MIS expert opinions, published MIS articles, and citation analysis. Four strata of journals are proposed utilizing a composite indicator of journal importance. The research has implications for MIS researchers seeking suitable publication outlets, for academic administrators evaluating research efforts, for editors wishing to establish MIS coverage policy, and for librarians making MIS journal acquisition decisions.
Adaptive texture image retrieval in transform domain

A large number of algorithms have been proposed to retrieve and analyze texture images. While much effort has been made to find algorithms applicable to all textures for superior retrieval performance, less work has been done to adaptively integrate various texture retrieval and analysis algorithms. As no individual texture retrieval algorithm is suited for every texture category, a hybrid scheme would outperform any individual method. In this paper, an adaptive retrieval scheme (ARS) for texture image indexing is proposed to dynamically adapt different transforms to different texture patterns for better retrieval performance. The experiments on the Brodatz texture database show that ARS significantly outperforms any individual transform.
Representing and using numerical information.

Issues of mental representation are central to cognitive psychology and indeed to psychology in general. This article synthesizes recent theoretical and empirical research concerning cognitive representations in one specific domain, that of numbers. First, several forms of cognitive numerical representation are defined, and the roles the various forms may play in numerical processing are considered. Then, two current representational issues that have generated some controversy are examined: In what form are arithmetic table facts (e.g., 4 x 7 = 28) stored in memory, and what forms of representation are involved in converting numerals from one form to another (as in reading 604 aloud as "six hundred four")? In the course of the discussion the major current theories of numerical cognition are described, with emphasis on how they differ in their assumptions about numerical representations and how these differences are reflected in the positions taken on various specific issues.
Altered ependyma and leptomeninges in transgenic mice that over express FGF2 and amyloid precursor protein: evidence for early hydrocephalus

Background Disruption of CNS microvessels and CSF-bordering cells (ependyma, choroid plexus and leptomeninges) can alter fluid flow among the CNS compartments. This leads to hydrocephalus. An excess of basic fibroblast growth factor (FGF2) or amyloid precursor protein (APP), from which A-Beta fragments derive, predisposes to altered fluid dynamics and amyloid retention. We combined these risk factors to accelerate development of hydrocephalus. Hypothesis: Doubly-transgenic animals, overexpressed for FGF2 and APP, have greater morbidity in respect to compromised CSF turnover and toxic A-Beta effects. We also postulated CSF/brain and blood/brain interfaces to be especially vulnerable in double overexpression.
Damage evolution during freeze–thaw cycling of cement mortar, studied by electrical resistivity measurement

Damage evolution during freeze-thaw cycling of cement mortar was found by electrical resistivity measurement to involve damage accumulating gradually cycle by cycle until failure. The damage inflicted during cooling was more significant than that inflicted during heating. Damage infliction occurred smoothly throughout cooling from 52 to 20 C. Failure occurred at the coldest point of a temperature cycle. Electrical resistivity measurement allowed simultaneous monitoring of temperature and damage. An increase in temperature caused the resistivity to decrease reversibly, but with hysteresis, which grew with cycling. The effects of freezing and thawing on the resistivity were small compared to the effect of temperature on the resistivity. D 2002 Elsevier Science Ltd. All rights reserved.
Monte Carlo methods in the physical sciences

I will review the role that Monte Carlo methods play in the physical sciences. They are very widely used for a number of reasons: they permit the rapid and faithful transformation of a natural or model stochastic process into a computer code. They are powerful numerical methods for treating the many-dimensional problems that derive from important physical systems. Finally, many of the methods naturally permit the use of modern parallel computers in efficient ways. In the presentation, I will emphasize four aspects of the computations: whether the computation derives from a natural or model stochastic process; whether the system under study is highly idealized or realistic; whether the Monte Carlo methodology is straightforward or mathematically sophisticated; and finally, the scientific role of the computation.
An integrative modeling approach to elucidate suction-feeding performance

SUMMARY Research on suction-feeding performance has mostly focused on measuring individual underlying components such as suction pressure, flow velocity, ram or the effects of suction-induced forces on prey movement during feeding. Although this body of work has advanced our understanding of aquatic feeding, no consensus has yet emerged on how to combine all of these variables to predict prey-capture performance. Here, we treated the aquatic predator–prey encounter as a hydrodynamic interaction between a solid particle (representing the prey) and the unsteady suction flows around it, to integrate the effects of morphology, physiology, skull kinematics, ram and fluid mechanics on suction-feeding performance. We developed the suction-induced force-field (SIFF) model to study suction-feeding performance in 18 species of centrarchid fishes, and asked what morphological and functional traits underlie the evolution of feeding performance on three types of prey. Performance gradients obtained using SIFF revealed that different trait combinations contribute to the ability to feed on attached, evasive and (strain-sensitive) zooplanktonic prey because these prey types impose different challenges on the predator. The low overlap in the importance of different traits in determining performance also indicated that the evolution of suction-feeding ability along different ecological axes is largely unconstrained. SIFF also yielded estimates of feeding ability that performed better than kinematic traits in explaining natural patterns of prey use. When compared with principal components describing variation in the kinematics of suction-feeding events, SIFF output explained significantly more variation in centrarchid diets, suggesting that the inclusion of more mechanistic hydrodynamic models holds promise for gaining insight into the evolution of aquatic feeding performance.
TRYPSINOGEN DEFICIENCY DISEASE.

An infant with severe growth failure, hypoproteinemia, and edema is described. Clinical and laboratory studies indicate that this disorder results from an impaired capacity to hydrolyze ingested protein. By means of specific pancreatic proteolytic enzyme assays, it was established that the primary defect is a complete absence of trypsinogen. Absence of trypsinogen results in secondary failure of activation of chymotrypsinogen and procarboxypeptidase. The disorder responds favorably to dietary management. Genetic aspects of this disease are discussed.
Spontaneously Arising mutL Mutators in Evolving Escherichia coli Populations Are the Result of Changes in Repeat Length

Over the course of thousands of generations of growth in a glucose-limited environment, 3 of 12 experimental populations of Escherichia coli spontaneously and independently evolved greatly increased mutation rates. In two of the populations, the mutations responsible for this increased mutation rate lie in the same region of the mismatch repair gene mutL . In this region, a 6-bp repeat is present in three copies in the gene of the wild-type ancestor of the experimental populations but is present in four copies in one of the experimental populations and two copies in the other. These in-frame mutations either add or delete the amino acid sequence LA in the MutL protein. We determined that the replacement of the wild-type sequence with either of these mutations was sufficient to increase the mutation rate of the wild-type strain to a level comparable to that of the mutator strains. Complementation of strains bearing the mutator mutations with wild-type copies of either mutL or the mismatch repair gene uvrD rescued the wild-type mutation rate. The position of the mutator mutations—in the region of MutL known as the ATP lid—suggests a possible deficiency in MutL9s ATPase activity as the cause of the mutator phenotype. The similarity of the two mutator mutations (despite the independent evolutionary histories of the populations that gave rise to them) leads to a discussion of the potential adaptive role of DNA repeats.
Dorsoventral Patterning: A Serpin Pinned down at Last

Dorsoventral patterning in Drosophila has long been known to involve a cascade of proteases, held in the inactive zymogen state prior to signaling. At long last, the prediction that a protease inhibitor is involved in this pathway has been shown to be true, with the identification of a serpin that plays a key part in Drosophila embryonic patterning.
Formulation of highly soluble poly(ethylene glycol)-peptide DNA condensates

Two poly(ethylene glycol) (PEG)-peptides were synthesized and tested for their ability to bind to plasmid DNA and form soluble DNA condensates with reduced spontaneous gene expression. PEG-vinyl sulfone or PEG-orthopyridyl disulfide were reacted with the sulfhydryl of Cys-Trp-Lys(18) (CWK(18)) resulting in the formation of nonreducible (PEG-VS-CWK(18)) and reducible (PEG-SS-CWK(18)) PEG-peptides. Both PEG-peptides were prepared on a micromole scale, purified by RP-HPLC in >80% yield, and characterized by (1)H NMR and MALDI-TOF. PEG-peptides bound to plasmid DNA with an apparent affinity that was equivalent to alkylated (Alk)CWK(18), resulting in DNA condensates with a mean diameter of 80-90 nm and zeta (zeta) potential of +10 mV. The particle size of PEG-peptide DNA condensates was constant throughout the DNA concentration range of 0. 05-2 mg/mL, indicating these to be approximately 20-fold more soluble than AlkCWK(18) DNA condensates. The spontaneous gene transfer to HepG2 cells mediated by PEG-VS-CWK(18) DNA condensates was over two orders of magnitude lower than PEG-SS-CWK(18) DNA condensates and three orders of magnitude lower than AlkCWK(18) DNA condensates. PEG-VS-CWK(18) efficiently blocked in vitro gene transfer by reducing cell uptake. The results indicate that a high loading density of PEG on DNA is necessary to achieve highly soluble DNA condensates that reduce spontaneous in vitro gene transfer by blocking nonspecific uptake by HepG2 cells. These two properties are important for developing targeted gene delivery systems to be used in vivo.
Standard Reference Materials to support measurement of fatty acids

The National Institute of Standards and Technology offers a variety of natural-matrix and solution-based Standard Reference Materials (SRM) that are characterized for fatty acid composition. The natural-matrix SRM are intended primarily for use as control materials, but other uses include method validation, the development of new analytical methods, and use as a component in achieving traceability of measurements. The use of complex-matrix reference materials for instrument calibration is not recommended; solution calibrants are better suited to this task. In addition to calibration, solution SRM can be used as spiking solutions for fortification of samples, in studying extraction recoveries, for developing chromatographic separations, and as authentic standards for identifying constituents in more complex-matrix extracts. The use of SRM to support the measurement of fatty acids is relevant to a broad spectrum of applications including compliance with and accuracy of nutritional labeling, food manufacturing tolerances (e. g., infant formulas), traceability of measurements for food exports, clinical nutritional measurements, and characterization of alternative energy sources (e. g., biodiesel). Currently, nearly 30 SRM are available with certified, reference, and information values reported for fatty acids. Additional SRM are under development that will complement these reference materials by providing fatty acid profiles in different types of matrices.
Targeting Hsp90 and its co-chaperones to treat Alzheimer's disease.

Introduction: Alzheimer’s disease, characterized by the accumulation of hyperphosphorylated tau and β amyloid (Aβ), currently lacks effective treatment. Chaperone proteins, such as the heat shock protein (Hsp) 90, form macromolecular complexes with co-chaperones, which can regulate tau metabolism and Aβ processing. Although small molecule inhibitors of Hsp90 have been successful at ameliorating tau and Aβ burden, their development into drugs to treat disease has been slow due to the off- and on-target effects of this approach as well as challenges with the pharmacology of current scaffolds. Thus, other approaches are being developed to improve these compounds and to target co-chaperones of Hsp90 in an effort to limit these liabilities.Areas covered: This article discusses the most current developments in Hsp90 inhibitors including advances in blood–brain barrier permeability, decreased toxicity and homolog-specific small-molecule inhibitors. In addition, we discuss current strategies targeting Hsp90 co-ch...
Porous Monoliths: Stationary Phases of Choice for High Performance Liquid Chromatography in Various Formats

Modern porous monoliths have been conceived as a new class of stationary phases for high performance liquid chromatography (HPLC) in classical columns in the early l990s and later extended to the capillary format. These monolithic materials are prepared using simple processes carried out in an external mold (inorganic monoliths) or within the confines of the column (organic monoliths and all capillary columns). These methods afford macroporous materials with large through-pores that enable applications in a rapid flow-through mode. Since all the mobile phase must flow through the monolith, the convection considerably accelerates mass transport within the monolithic separation medium and improves the separations. As a result, the monolithic columns perform well even at very high flow rates. The applications of monolithic capillary columns are demonstrated on numerous separations in the HPLC mode.
On Some Issues of United States Tornado Climatology

Abstract A continuing problem in dealing with climatology data concerning tornadoes in the United States is the validity of the quantitative information contained in the various available data bases. Two aspects of tornado data are discussed: the F-scale rating and the occurrence of very long path length events. The argument is advanced that the F-scale is more properly thought of as a damage scale than as an intensity scale. Failing to recognize this leads to confusion and controversy regarding the F-scale ratings assigned to events in the data base. Changing perceptions of tornadoes have led to some questions concerning the actual frequency of very long path lengths, on the order of 100 statute miles (160.9 km) or more. Evidence is presented that at least some of the events classified as having long tracks are most likely the result of misinterpreting the results of a series of short-path tornadoes, produced by a single supercell thunderstorm. Some discussion is presented concerning the implications of ...