cssi/SciSciGPT-SciSciNet huggingface dataset:
The gic for model selection : a hypothesis testing approach

Abstract We consider the model (subset) selection problem for linear regression. Although hypothesis testing and model selection are two different approaches, there are similarities between them. In this article we combine these two approaches together and propose a particular choice of the penalty parameter in the generalized information criterion (GIC), which leads to a model selection procedure that inherits good properties from both approaches, i.e., its overfitting and underfitting probabilities converge to 0 as the sample size n→∞ and, when n is fixed, its overfitting probability is controlled to be approximately under a pre-assigned level of significance.
Electric vehicle smart charging and vehicle-to-grid operation

Electric vehicle EV charging must be optimised for grid load while guaranteeing that drivers' schedules and range requirements are met. A system encompassing EV owner input via a mobile application, an aggregation middleware, a charge scheduling and vehicle-to-grid V2G operation algorithm and a radio-frequency identification reader is proposed. The algorithm's parameters and effectiveness are presented and discussed using simulation results. Simulation results show the algorithm to effectively optimise charging and V2G operation for a given electricity price curve. The proposed system is shown to alleviate grid load during peak hours, take advantage of off-peak charging benefits and generate revenue for the parking garage operator.
Evaluating Distributed Platforms for Protein-Guided Scientific Workflow

Complex and large-scale applications in different scientific disciplines are often represented as a set of independent tasks, known as workflows. Many scientific workflows have intensive resource requirements. Therefore, different distributed platforms, including campus clusters, grids and clouds are used for efficient execution of these workflows. In this paper we examine the performance and the cost of running the Pegasus Workflow Management System (Pegasus WMS) implementation of blast2cap3, the protein-guided assembly approach, on three different execution platforms: Sandhills, the University of Nebraska Campus Cluster, the academic grid Open Science Gird (OSG), and the commercial cloud Amazon EC2. Furthermore, the behavior of the blast2cap3 workflow was tested with different number of tasks. For the used workflows and execution platforms, we perform multiple runs in order to compare the total workflow running time, as well as the different resource availability over time. Additionally, for the most interesting runs, the number of running versus the number of idle jobs over time was analyzed for each platform. The performed experiments show that using the Pegasus WMS implementation of blast2cap3 with more than 100 tasks significantly reduces the running time for all execution platforms. In general, for our workflow, better performance and resource usage were achieved when Amazon EC2 was used as an execution platform. However, due to the Amazon EC2 cost, the academic distributed systems can sometimes be a good alternative and have excellent performance, especially when there are plenty of resources available.
The reform of higher education in Egypt

The historical background of higher education in Egypt, the present organizational structure, as well as current challenges and constraints are described to anchor an assessment of the strategies for educational reform which are presently underway. Higher education in Egypt witnessed uncontrolled growth throughout the decade of the 1970s until 1983 when several reforms were initiated. Three broad goals have been targeted: containing enrollments through new admissions policies and testing practices; improving program quality by updating curriculum and focusing on important learning outcomes; and promoting responsible fiscal management by developing management information systems, training administrators in their use, and exploring cost recovery from various sources. This article addresses the progress of these reforms to date, makes recommendations for their fuller development and implementation, and offers comments on their significance to other developing nations.
Promoting Student Engagement and Creativity by Infusing Art Across the Curriculum: The Arts Integration Initiative at Oklahoma City University

Christopher E. Garrett describes a faculty learning community program at Oklahoma City University that focused on improving teaching and learning through integrating the arts in a variety of disciplines, some of which may surprise you.
FCC Logging and Operator Rules

The Federal Communications Commission has adopted new rules concerning the qualifications of operators of broadcast stations. The transmitting equipment of each station will be subject to periodic inspections and a maintenance log pertaining thereto will be kept. Clarifications are listed concerning present entries in the operating log of a station. In case the station contemplates the use of automatic logging equipment, certain conditions and requirements have to be met. An automatic transmitter, if such were available, capable of correcting itself to operate in accordance with FCC rules would, of course, obviate the need for any logs or monitoring equipment.
Detoxication of Sulfur Half-Mustards by Nucleophilic Scavengers: Robust Activity of Thiopurines

Sulfur mustard (bis-(2-chloroethyl)sulfide) has been used in chemical warfare since World War I and is well known as an acutely toxic vesicant. It has been implicated as a carcinogen after chronic low-level exposure and is known to form interstrand cross-links in DNA. Sulfur and nitrogen mustards are currently of interest as potential chemical threat agents for terrorists because of ease of synthesis. Sulfur mustard and monofunctional analogues (half-mustards, 2-[chloroethyl] alkyl sulfides) react as electrophiles, damaging cellular macromolecules, and thus are potentially subject to scavenging by nucleophilic agents. We have determined rate constants for the reaction of four purine derivatives that contain nucleophilic thiol moieties with several sulfur-half-mustards. Three of these compounds, 2,6-dithiopurine, 2,6-dithiouric acid, and 9-methyl-6-mercaptopurine, exhibit facile reaction with the electrophilic mustard compounds. At near neutral pH, these thiopurines are much better nucleophilic scavengers of mustard electrophiles than other low molecular weight thiols such as N-acetyl cysteine and glutathione. Progress curves calculated by numerical integration techniques indicate that equimolar concentrations of thiopurine provide significant reductions in the overall exposure to the episulfonium ions, which are the major reactive, electrophiles produced when sulfur mustards are dissolved in aqueous solution.
Minority report on the Bush doctrine

This essay provides a framework for understanding the implications of the Bush administration's War on Terror, through an analysis of Stephen Spielberg's 2002 futuristic film, Minority Report. In brief, the film explores the trade‐offs between security and freedom, overlaid upon intersections between free will and external determinism, by following the fate of John Anderton, an anti‐crime crusader in the US government's Department of Precrime. Anderton is a true believer in Precrime, a government agency that uses “precognitive” human psychics and advanced brain‐imaging technology to discover and prevent violent crime before it occurs. Spielberg's film, released in summer 2002, has been called prescient for the eerie similarity between Precrime and post‐Patriot Act Department of Justice operations. The analysis suggests a broader relevance, in illuminating the ethical dilemmas and practical political pitfalls of the administration's new foreign policy doctrine of “anticipatory self‐defense,” or preemptive ...
Determination of monovalent and divalent cations and chloride in the carbacephalosporin loracarbef by ion chromatography

Abstract Sensitive determination of monovalent and divalent cations and chloride in the carbacephalosporin antibiotic loracarbef can be achieved by separation on a high-capacity cation-exchange column followed by chemically suppressed conductivity detection. The methods developed in our laboratory for these determinations are characterized by the absence of matrix interference, rapid separation, ease of sample preparation and good sensitivity. Of these benefits, it is the minimization of matrix interference supplied by micromembrane chemical suppression that has made this technique so powerful for this application. Advantage is taken of the acid-base chemistry of loracarbef, resulting in a drastic reduction in its concentration in the eluent prior to detection of the analytes of interest. Linearities in the presence of the matrix (coefficient of determination ⪢ 0.995) and recoveries from the matrix are excellent (100 ± 2%). However, when the suppression components exhibit decreased efficiency, systems employing eluents composed of both hydrochloric and diaminopropionic acids are susceptible to problems such as poor peak shape, high background conductivity, and noise thus making accurate determinations difficult. Both the suppression system and the eluent are assessed in relation to the sources of high background conductivity and noise.
Meeting the Challenges of Police Governance in Trinidad and Tobago

In response to a crisis of heightened crime and lowered public confidence, Trinidad and Tobago has embarked upon a package of reforms intended to transform the governance, and ultimately the performance, of its Police Service. Trinidad and Tobago's governance problems issue from its colonial heritage and conflicts between cultural groups in the society. The old system of governance created the appearance of governance, but dysfunctional results. Adapted from the model of the Independent Commission on Policing for Northern Ireland, Trinidad and Tobago's reformed system consolidates more administrative authority in the office of police commissioner, enhances the Government's capacity to provide policy direction, while creating independent watchdog entities to hold the Police Service accountable. These arrangements afford the opportunity to strengthen the legitimacy of all governing entities, greater internal and external control, transparency and effective technical management. But success ultimately requires major changes in the habits of all governing entities, changes that only committed leadership in Government, the police and party politics can ensure.
On-chip supercontinuum optical trapping and resonance excitation of microspheres

We demonstrate the simultaneous optical manipulation and analysis of microscale particles in a microfluidic channel. Whispering gallery modes (WGMs) in dielectric microspheres are excited using the evanescent field from a silicon nitride waveguide. A supercontinuum source is used to both trap the microspheres to the surface of the waveguide and excite their resonant modes. All measurements are in plane, thus providing an integrated optofluidic platform for lab-on-a-chip biosensing applications.
Wegener granulomatosis: Prostatic involvement and bladder outlet obstruction

Abstract Renal involvement is present in about 90 percent of patients with Wegener granulomatosis and only sporadically is the remainder of the genitourinary tract affected. Prior to 1974, the mean survival rate was five months from the time of diagnosis. Since 1974, therapy with cytotoxic drugs, cyclophosphamide or azathioprine, has produced remissions in about 95 percent of patients. Herein, a case is reported that presented with bladder outlet obstructive symptoms, secondary to prostatic involvement with Wegener granulomatosis. After treatment with cyclophospharnide and prednisone, the patient's urinary obstructive symptoms promptly resolved.
Carbon, sulfur and O2 across the Permian–Triassic boundary

Abstract A model for the carbon and sulfur cycles across the Permian–Triassic boundary has been constructed from carbon and sulfur isotopic data. Results indicate a drop in global organic matter burial, the formation of an anoxic deep ocean, and a large drop in atmospheric oxygen over the time span 270 to 240 Ma. Much of these changes were probably due to a drop in terrestrial productivity and preservation and an increase in global aridity.
Role of Internet-based information flows and technologies in electoral revolutions: The case of Ukraine’s Orange Revolution

Internet-based information and communication technologies (ICTs) and the information flows they support have played an important role in the advancement of society. In this paper we investigate the role of Internet-based ICTs in electoral revolutions. Employing a case study approach, we examine the part played by ICTs during the Orange Revolution in Ukraine (2000-2004). Roles and activities of the dissenters, as well as their associates, the incumbent authorities and their allies are analyzed with regard to Internet-based technologies during the electoral revolution in Ukraine. The case of the Orange Revolution is particularly salient, as even though only one-two percent of the Ukrainian population had access to the Internet, this was sufficient to mobilize the citizens towards an eventually successful revolution. This paper lays the groundwork for further investigations into use of ICTs by political dissenters.
Circumnuclear Shock and Starburst in NGC 6240: Near-IR Imaging and Spectroscopy with Adaptive Optics

We have obtained adaptive optics, high spatial resolution (0.15 arcsecond) K-band spectra and images of the region around the two active nuclei in NGC 6240 which show the presence of circumnuclear shocks. The data are consistent with the thermal excitation mechanism being the dominant one in the nuclear region. UV fluorescence and associative detachment may also contribute to the fraction of the energy emitted through molecular hydrogen transitions. The near-IR continuum emission appears closely associated with the two active nuclei. The morphological similarities between the near-IR images and the Chandra X-ray images indicate the same mechanisms may be responsible for the emission in near-IR and X-ray band.
Protracted spawning of St Lawrence River northern pike (Esox lucius): simulated effects on survival, growth, and production

Abstract – An individual-based early life history model demonstrated that the timing and distribution of St Lawrence River northern pike (Esox lucius) spawning could affect subsequent young-of-year (YOY) production during nursery and influence year-class formation. Three different spawning patterns have emerged from empirical studies, where egg deposition occurred along the entire littoral gradient beginning in seasonally flooded emergent habitats in tributaries, progressing to submerged aquatic vegetation in shallow bays, and ending in deep water littoral habitats (up to 6 m). The spawning period is protracted, and typically lasts 6–8 weeks due to the presence of a strong thermal gradient. The model used temperature as the driving variable to predict egg abundance, stage-specific development, growth, survival, and ultimately relative production of YOY northern pike within 1-ha plots representative of the three habitats. Earlier spawning (mean 21 days) and higher mean daily survival and growth yielded higher YOY net production for tributaries (mean = 3095.4 g ha−1, SD = 2028.6) relative to the shallow bay habitat (202.5 g ha−1, SD = 125.7). In contrast, deep littoral habitat represented an ecological sink with little production (<0.9 g ha−1). The results demonstrate the importance of the linkage between spawning and nursery processes in determining reproductive success.
Best practices in information technology (IT) management: insights from K‐12 schools’ technology audits

Information regarding best practices of information technology (IT) management in K‐12 schools provides school leaders with a basis for developing their own IT systems or evaluating their existing systems. Important as this information is, limited literature coverage exists on this topic. Over 100 technology audits conducted by graduate students in school organizations in north‐east Ohio in the United States have yielded insights of best practices that school leaders should find useful. The insights discussed in this article include attention to the access rate of users, leadership promise, technology planning, staff development, technical support, strategic hardware and software procurement, the technology budget, and an expanded view of infrastructural facilities. The article concludes with recommendations to school leaders who are interested in taking their IT practices to another level of excellence.
The impact of patient-centered communication on patients' decision making and evaluations of physicians: a randomized study using video vignettes.

Abstract Objective To assess the impact of patient-centered communication (PCC) behaviors on patients' evaluations of physicians and acceptance of clinical recommendations. Methods We randomized 248 patients to view video-recorded, standardized vignettes, depicting a cardiologist using a high vs. low degree of PCC while recommending bypass surgery to a patient with angina and 3-vessel coronary artery disease. We compared patients' ratings of the physician and their decision making in response to the physician's recommendation, for high vs. low PCC vignettes. Results Patients viewing high PCC vignettes rated the video physician more favorably overall (3.01 vs. 2.12, p p p p Conclusion Patients expressed greater confidence in physicians who used more PCC behaviors, and greater willingness to accept an evidence-based recommendation. Practice implications PCC may make physicians more effective in the delivery of evidence-based care.
Another approach to the Truncated Pentagonal Number Theorem

Recently, in three separate papers, Andrews and Merca, Yee, and Kolitsch and Burnette proved some results concerning the Truncated Pentagonal Number Theorem. In this paper, a family of generating functions that keeps track of the number of different parts in a partition will be studied. This family of generating functions can be used to get the earlier results on the Truncated Pentagonal Number Theorem as well as several other results.
Disulfonic stilbenes prevent β-amyloid (25–35) neuronal toxicity in rat cortical cultures

Anion exchange proteins were recently identified among some of the proteins found clustered together in the hallmark plaques and tangles of Alzheimer's patient's brains. Anion exchange proteins underlie chloride/bicarbonate exchange, cell shape regulation and participate in removal of aged cells by the immune system. In this study we compared the neuroprotective efficacy of an anion exchanger inhibitor, 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS), against beta-amyloid((25-35)) neurotoxicity, staurosporine-induced apoptosis and glutamate-induced necrosis in primary cortical cultures. We demonstrate potent neuroprotective efficacy with DIDS against beta-amyloid((25-35)) and staurosporine, but not against glutamate. Our results suggest that anion exchange proteins may play an important role in beta-amyloid toxicity and that DIDS may represent a viable therapeutic agent for Alzheimer's disease.
Collection Development in an Era of Full-Text and “Package Deals”

The emergence of digitized full-text databases for subscription, either solely or as part of “package deals” offered by database providers and consortia, has provided the opportunity for academic i...
The influence of ancymidol on morphology, anatomy, and chlorophyll levels in developing and mature Helianthus annuus leaves

Ancymidol foliar spray at 132 mg·liter−1 a.i. modified leaf anatomy of developing Helianthus annuus L. ‘Mammoth Russian’ leaves, but not of mature leaves. Ancymidol was effective in retarding plant growth when applied at the young seedling or at a more mature stage of growth. Ancymidol increased leaf weight per unit area and chlorophyll content on an area and unit weight basis, regardless of stage of leaf development. Total chlorophyll per leaf was also increased in mature leaves. Thus, darker green foliage due to increased chlorophyll content and modified leaf anatomy responses were determined to be independent effects.
Seismic Image Resolution: Numerical Investigation of Role of Migration Imaging Operator

The resolution of seismic migration imaging is often given as some function of the data aperture, the size of the Fresnel zone at the image location, the frequency of the data used in the migration and the illumination of the target region. Traditional resolution analysis is based on calculation of a Point Spreading Function (PSF) in the wavenumber domain from the scattering wavenumbers at the image point. This spectral representation can be converted into a space-domain PSF by Fourier Transform. However, other issues influence image resolution or distort migrated images. For example, the velocity model is generally not reliably known and variations of the model from the true structure can have a significant impact on image focus, thus reducing resolution. Another factor that limits resolution is the type and accuracy of the propagator used in imaging. To compare the resolution of images obtained when using ray-based Kirchhoff migration with that obtained from wave equation migration, we developed a 2D heterogeneous model that can be numerically simulated. Poststack migrations of exploding reflector data obtained for the model show that the PSF are influenced by the migration operator and are not necessarily the same as expected from the range of scattering wavenumbers estimated using a simple analysis approach.
Classification of exporting firms according to sales and growth into a share matrix

An export growth share matrix, which divides firms into four categories based on export percentage and anticipated growth, was developed from an analysis of past literature and an empirical data base. Implications are then developed for each category of firms to help the government encourage exporting and to improve managerial decisions regarding marketing abroad.
Preparation of magnetic graphene composites with hierarchical structure for selective capture of phosphopeptides

A novel graphene composite affinity material consisting of graphene scaffolds, Fe3O4 nanoparticles for actuation and fully covered porous titania nanostructures as affinity coating has been designed and constructed. The obtained magnetic graphene composites have a saturation magnetization (Ms) value of 7.3 emu g−1, a BET specific surface area of 111.8 m2 g−1 and an average pore size of 15.1 nm for the porous affinity coating. The multifunctional graphene composites can realize the selective capture and convenient magnetic separation of target phosphopeptides by taking advantage of the decorated magnetic nanoparticles, highly pure and well crystallized affinity coating, and unique porous structure. The sensitivity and selectivity of the affinity graphene composites were evaluated using digests of standard proteins and complex biosamples as well as by comparison with the widely used TiO2 affinity microspheres. The results show that the affinity graphene composites can realize selective capture and rapid separation of low-abundant phosphopeptides from complex biological samples. Thus, this work will contribute to future applications in the purification and separation of specific biomolecules, in particular low-abundant phosphopeptide biomarkers.
Characterization of a binding protein specific for 17β-estradiol and estrone in rat pregnancy plasma

Abstract 1. 1. The estrogen-binding component in the plasma of the pregnant rat has been characterized further. As established by competitive binding with [ 3 H]estradiol, binding virtually was restricted to estrone and 17β-estradiol. 2. 2. The binder sedimented in sucrose gradients at 4.1 S. It likely is a protein because trypsin abolished the 4.1-S binding peak; ribonuclease and deoxyribonuclease did not. 3. 3. Results of gel filtration on calibrated columns of Sephadex G-200 imply a molecular weight of approx. 50 000 and a Stokes radius of 30 A. The calculated frictional coefficient, 1.2, suggests that the material is globular. 4. 4. The apparent association constant, estimated by equilibrium dialysis, was 1·10 9 M −1 for 17β-estradiol. Plasma from 14-day pregnant rats had a binding capacity of 3.6·10 −10 mole (97.6 ng) of 17β-estradiol per ml. 5. 5. The binding protein of pregnant-rat plasma differs from the sex steroid-binding globulin of human plasma in its binding and physical properties.
Generalized (η,ρ)-Invex Functions and Global Semiparametric Sufficient Efficiency Conditions for Multiobjective Fractional Programming Problems Containing Arbitrary Norms

The purpose of this paper is to develop a fairly large number of sets of global semiparametric sufficient efficiency conditions under various generalized (η, ρ)-invexity assumptions for a multiobjective fractional programming problem involving arbitrary norms.
Effect of lifestyle modification on adipokine levels in obese subjects with insulin resistance.

Objective: To study the effect of weight loss in response to a lifestyle modification program on the circulating levels of adipose tissue derived cytokines (adipokines) in obese individuals with insulin resistance. Research Methods and Procedures: Twenty-four insulin-resistant obese subjects with varying degrees of glucose tolerance completed a 6-month program consisting of combined hypocaloric diet and moderate physical activity. Adipokines [leptin, adiponectin, resistin, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6)] and highly sensitive C-reactive protein were measured before and after the intervention. Insulin sensitivity index was evaluated by the frequently sampled intravenous glucose tolerance test. Results: Participants had a 6.9 ± 0.1 kg average weight loss, with a significant improvement in sensitivity index and reduction in plasma leptin (27.8 ± 3 vs. 23.6 ± 3 ng/mL, p = 0.01) and IL-6 (2.75 ± 1.51 vs. 2.3 ± 0.91 pg/mL, p = 0.012). TNF-α levels tended to decrease (2.3 ± 0.2 vs. 1.9 ± 0.1 pg/mL, p = 0.059). Adiponectin increased significantly only among diabetic subjects. The reductions in leptin were correlated with the decreases in BMI (r = 0.464, p < 0.05) and with changes in highly sensitive C-reactive protein (r = 0.466, p < 0.05). Discussion: Weight reduction in obese individuals with insulin resistance was associated with a significant decrease in leptin and IL-6 and a tendency toward a decrease in circulating TNF-α, whereas adiponectin was increased only in diabetic subjects. Further studies are needed to elucidate the relationship between changes of adipokines and the health benefits of weight loss.
A review of PV/T technologies: Effects of control parameters

Abstract Both air and water cooled PV/T collectors have enjoyed growing attentions in recent years. Investigators have reported PV/T research data within a wide range of control parameters. In this paper, the effects of the major control parameters on the thermal/electrical performance of PV/T collectors are compiled and reviewed. Figures and tables are provided to give an overall picture about how PV/T performance could be improved in terms of these parameters. Although investigators understand the effects of different parameters, the improvement of PV/T performance by optimizing these parameters has not been fully realized.
An inhibitor of integrin receptors blocks long-term potentiation.

BEHAVIORAL AND NEURAL BIOLOGY RAPID COMMUNICATION An Inhibitor of Integrin Receptors Blocks Long-Term Potentiation U . STAUBLI, P. VANDERKLISH, AND G. LYNCH ] Center for the Neurobiology of Learning and Memory, University of California, Irvine, California 92717 A wide variety of cell-cell and cell-matrix interactions are now known to be mediated by members of a large family of heterodimeric trans- membrane proteins known as integrins (Ruoslahti & Pierschbacher, 1987). Integrins possess an extracellular receptor site that binds particular matrix components including laminin, fibronectin, vitronectin, and col- lagens, and an intracellular domain that associates with elements of the membrane cytoskeleton. Given that they play a critical role in forming adhesive contacts in many types of cells, the possibility exists that in- tegrins are also important in the development and maintenance of syn- aptic contacts. In support of this is the observation that integrin-like proteins are found in the nervous system and participate in the devel- opment of anatomical organization. Long-term potentiation (LTP) is as- sociated with changes in the ultrastructure of the synaptic region and possibly the formation of new contacts (Lee, Schottler, Oliver, & Lynch, 1980), effects that might well be expected to involve adhesion proteins including integrins. To explore this idea, we incubated hippocampal slices with the RGDS (Arg-Gly-Asp-Ser) tetrapeptide, a compound that acts as a partial competitive inhibitor of the interactions between integrins and their endogenous ligands (Rouslahti & Pierschbacher, 1987), and tested for LTP in the Schaffer-commissural projections in field CA1. Slices were prepared and maintained in an interface chamber (i.e., surface exposed to a moist, oxygenated atmosphere) using methods and techniques described elsewhere. Two to four slices from a single hip- pocampus were typically tested for LTP. This involved placing two hi- Research was supported by the Air Force Office of Scientific Research (AFOSR Grant 86-0099) to G.L. and the National Science Foundation (NSF Grant BNS-8809316) to U.S. Reprint requests should be addressed to U. Staubli. Copyright © 1990 by Academic Press, Inc, All rights of reproduction in any form reserved.
The effect of backside roughness on Al interconnect dimensions for RF CMOS SOI devices

Backside roughness variation on incoming Silicon-On-Insulator (SOI) wafers can cause systematic variations in the dimensions of Al interconnects. Wafers with more backside roughness are more effectively cooled during reactive ion etching (RIE), resulting in a lower wafer temperature during the etch, and a larger line width. The backside roughness of the SOI substrate must be considered in order to minimize wafer-to-wafer variations in the Al linewidth.
Fast response to East Coast earthquake advances seismic science

At a briefing on 23 August, exactly 1 year after a magnitude 5.8 earthquake shook a large portion of the East Coast of the United States, scientists and public safety officials called it a significant seismic event that could help with better understanding the potential for future seismic events in the region. Officials also are moving forward with a number of measures to improve public response efforts to East Coast earthquakes. During the briefing, held in front of the Washington Monument in Washington, D. C., Marcia McNutt, director of the U.S. Geological Survey (USGS), said the event—with its epicenter near the town of Mineral, Va., in Louisa County—was “the most significant” earthquake ever to strike the United States east of the Rocky Mountains. She said that more people experienced the quake than any other in U.S. history. About 148,000 people reported ground shaking on the USGS “Did You Feel It?” Web site, and those reports helped to determine within minutes that the energy had radiated out of the earthquake in an asymmetric manner to the northeast and southwest. “In a sense, this earthquake took aim, and Washington, D. C., was in its path,” she said.
Anciently duplicated genes reduce uncertainty in molecular clock estimates

Deciphering the histories of lineages as they have unfolded over billions of years, and placing them in the context of the known fossil record and Earth’s biogeochemical events, is a challenging task in evolutionary biology. Shortly after discovering the molecular structure of DNA and determining the first amino acid sequences of proteins, it was recognized that the evolutionary distances among lineages could be estimated from the changes observed in nucleotide and amino acid sequences (substitutions). Combined with the hypothesis that steady accumulation of substitutions over time is analogous to the “ticking” of a clock [and hence the moniker “molecular clock” (1)], the relative divergence times among lineages could be estimated from the genetic distances among them. Estimating the times of the major evolutionary events in the history of Earth’s biosphere could be made when the branches of the evolutionary tree are calibrated with available fossil evidence, allowing conversion of the relative divergence times to the absolute estimates (2). Realization that the molecular clock “ticks” unevenly within and across genes, among different lineages and over time, as well as a scarce and often controversial fossil record, ultimately led to a development of a new class of Bayesian “relaxed clock” models (3). These models do not require all lineages to evolve at the same rate and allow incorporation of heterogeneous (as well as vague) prior information from multiple genes, a large number of taxa, and multiple calibration points (3). Despite these methodological advances, dating various past evolutionary events has continued to produce conflicting estimates and wide uncertainty intervals. In PNAS, Shih and Matzke (4) introduce a clever approach to decrease the uncertainty associated with the inferred dates via additional constraints provided by anciently duplicated gene families.
The escape of O from Mars: Sensitivity to the elastic cross sections

Abstract We have predicted the escape fluxes of energetic O from Mars for high and low solar activity models of the martian thermosphere, using a Monte Carlo code to determine the escape probabilities as a function of altitude and energy. Among the most important inputs to this code are the integral and differential elastic cross sections for hot O with various target species in the background atmosphere. In previous studies, we assumed that the integrated elastic cross section for each target species was 3 × 10 −15 cm 2 . Here we adopt more realistic elastic cross sections for O with each target species. We have identified calculations or measurements of such cross sections as a function of energy for O with seven of the twelve background species in our models. We adopt as constant a value that is appropriate to the 2–3 eV energy range, which is just above the escape energy of O. For the five background species for which there are no data, we estimate the elastic cross sections as similar to those of a species of approximately the same size. The most important species for which there are no reported cross sections for elastic interactions with O is CO 2 , which is the major species in the martian thermosphere below about 200 km. For our nominal model we adopt an elastic cross section that is slightly larger than that for O with N 2 . We then test the sensitivity of the model to the O–CO 2 cross section by adopting values that are smaller or larger than this value. We report O escape probabilities for four cases, and the resulting escape fluxes and rates. There are small but not insignificant differences between the escape probabilities and fluxes for these cases. For low solar activity there is a factor of 2–3 range in the computed escape fluxes; for high solar activity, the factors are smaller, of the order of 1.5 or less. We compare these results with those of our previous calculations for a common constant collision cross section. We find that the O escape fluxes for the latter case, which are of the order of (2–4) × 10 8 cm −2 s −1 , are larger by factors of 9–28 than those of the four test cases here, which are in the range ∼(1–6) × 10 7 cm −2 s −1 .
Biochemical and Genetic Analysis of the Four DNA Ligases of Mycobacteria

Mycobacterium tuberculosis encodes an NAD(+)-dependent DNA ligase (LigA) plus three distinct ATP-dependent ligase homologs (LigB, LigC, and LigD). Here we purify and characterize the multiple DNA ligase enzymes of mycobacteria and probe genetically whether the ATP-dependent ligases are required for growth of M. tuberculosis. We find significant differences in the reactivity of mycobacterial ligases with a nicked DNA substrate, whereby LigA and LigB display vigorous nick sealing activity in the presence of NAD(+) and ATP, respectively, whereas LigC and LigD, which have ATP-specific adenylyltransferase activity, display weak nick joining activity and generate high levels of the DNA-adenylate intermediate. All four of the mycobacterial ligases are monomeric enzymes. LigA has a low K(m) for NAD(+) (1 microm) and is sensitive to a recently described pyridochromanone inhibitor of NAD(+)-dependent ligases. LigA is able to sustain growth of Saccharomyces cerevisiae in lieu of the essential yeast ligase Cdc9, but LigB, LigC, and LigD are not. LigB is distinguished by its relatively high K(m) for ATP (0.34 mm) and its dependence on a distinctive N-terminal domain for nick joining. None of the three ATP-dependent ligases are essential for mycobacterial growth. M. tuberculosis ligDDelta cells are defective in nonhomologous DNA end joining.
Temperature-composition phase diagrams of binary blends of block copolymer and homopolymer

Abstract The temperature–composition phase diagrams for six pairs of diblock copolymer and homopolymer are presented, putting emphasis on the effects of block copolymer composition and the molecular weight of added homopolymers. For the study, two polystyrene- block -polyisoprene (SI diblock) copolymers having lamellar or spherical microdomains, a polystyrene- block -polybutadiene (SB diblock) copolymer having lamellar microdomains, and a series of polystyrene (PS), polyisoprene (PI), and polybutadiene (PB) were used to prepare SI/PS, SI/PI, SB/PS, and SB/PB binary blends, via solvent casting, over a wide range of compositions. The shape of temperature–composition phase diagram of block copolymer/homopolymer blend is greatly affected by a small change in the ratio of the molecular weight of added homopolymer to the molecular weight of corresponding block ( M H,A / M C,A or M H,B / M C,B ) when the block copolymer is highly asymmetric in composition but only moderately even for a large change in M H,A / M C,A ratio when the block copolymer is symmetric or nearly symmetric in composition. The boundary between the mesophase (M 1 ) of block copolymer and the homogeneous phase (H) of block copolymer/homopolymer blend was determined using oscillatory shear rheometry, and the boundary between the homogeneous phase (H) and two-phase liquid mixture (L 1 +L 2 ) with L 1 being disordered block copolymer and L 2 being macrophase-separated homopolymer was determined using cloud point measurement. It is found that the addition of PI to a lamella-forming SI diblock copolymer or the addition of PB to a lamella-forming SB diblock copolymer gives rise to disordered micelles (DM) having no long-range order, while the addition of PS to a lamella-forming SB diblock copolymer retains lamellar microdomain structure until microdomains disappear completely. Thus, the phase diagram of SI/PI or SB/PB blends looks more complicated than that of SI/PS or SB/PS blends.
Low noise current optoelectronic integrated receiver with an internal equalizer for Gbit/s long wavelength optical communications

The optoelectronic integrated circuit (OEIC) attracts much attention because of its potential for high speed and low noise operation. As for the receivers of long wavelength optical communications, a PIN photodiode and field effect transistors (FETs), such as junction FETs and high electron mobility transistors (HEMTs), have been integrated using various growth and fabrication techniques.1-3 Although operation of receiver OEICs at Gbit/s data rate has been reported, most of the receivers need an external buffer stage and external equalizer to achieve high sensitivity and good responsivity. The first (to our knowledge) successful fabrication of a receiver OEIC with internal equalizer and buffer stage is demonstrated.
Role of membrane lipid asymmetry in aging

Recent advances in our understanding of the asymmetric distribution of lipids across nervous system membranes coupled with the application of biophysical techniques to examine transbilayer structure and function have led to the formulation of a new hypothesis. The author hopes that the insights presented herein will stimulate investigation into this developing new field. The theory provides an approach to correlation the accumulation of nervous tissue membrane peroxidative and cross-linking damage, the loss of transbilayer lipid asymmetry, and loss of transbilayer neuroendocrine, transport, secretory and immunoregulatory functions. Central to this scheme is the role of membrane lipid asymmetry in regulation to and/or coupling of transbilayer functions.
A New Class of Single Event Soft Errors

A new class of single event transient errors, referred to here as "single event disturb errors", is described. These errors are potentially as troublesome as single event upsets. Computer simulations demonstrate that disturb errors have critical charges less than or equal to those for logic upset in all circuits, and rates approaching those for upset in state-of-the-art sRAM circuits with polysilicon resistor loads. The errors cannot be prevented by resistive decoupling, and elude many current single event error testing methods.
Clinical aspects of depression in a home for the aged.

: This study concerns the patterns and treatment of depressive syndromes occurring in 26 of the residents of a home for the aged, during a three-year period. Depression is an omnipresent threat in such a setting. Admission to a geriatric facility, often the stimulus for a depressive reaction, may be experienced as a massive psychosocial insult calling for major coping activity on the part of the patient. Persons with a prior history of depressive episodes are most likely to become depressed at this time. Depressive behavior also can occur after a period of residence and usually is a reaction to an experienced loss (which may be judged minor by the staff) or a clue to somatic decline. Treatment of depression in a geriatric facility requires first of all an active, optimistic program which is individually oriented. Psychiatric treatment is required for those who are more severely depressed. The biological and social fragility of this group of patients is stressed.
Determination of the enantiomeric composition of guest molecules by chemometric analysis of the UV-visible spectra of cyclodextrin guest-host complexes.

Multivariate statistical techniques were applied to the UV spectra of a series of solutions at pH 12 containing a fixed concentration (30 mM) of β-cyclodextrin (β-CD) and a fixed concentration (15 mM) of 2-phenylglycine (φ-Gly) with various known enantiomeric compositions. Multivariate correlation of the spectral data for the solutions containing the φ-Gly/β-CD guest−host complexes with the known enantiomeric composition of the φ-Gly samples was accomplished by partial-least-squares regression. When the multivariate model was used to predict the enantiomeric purity of a test set of samples over the mol fraction range of 0.5−0.9 R-φ-Gly, the average magnitude of the relative errors in the mol fraction determination of enantiomeric composition was 3%. A plot of the enantiomeric composition predicted by the model versus the known enantiomeric composition of the calibration set gave a straight line with a correlation coefficient of 0.955, a slope of 1.05, and an offset of 5.61 × 10-4.
Radiofrequency Ablation With a Gaussian Heat Source in a Realistic Reconstructed Hepatic Geometry

This study describes a detailed methodology for modeling a three-dimensional radiofrequency ablation procedure using reconstructed porous tissue geometries. In this study, MRI images of a sectioned liver tissue containing arterial vessels are converted into a finite element mesh. An rf heat source in the form of a spherically symmetric Gaussian distribution, fit from a previously computed profile, is employed Computations of temperature rise were performed for transient rf procedures in the case where the tumor is located near the bifurcation point of a hepatic artery. Results demonstrate a significant effect due to convective cooling by the large vessels. Substantial asymmetries in the temperature profiles indicate ablation procedures that may achieve adequate tumor destruction in some regions, but that elevate the temperature only minimally in other regions, thereby permitting possible tumor recursion. These critical features of the temperature field are due to the directional nature of the arterial flow and are difficult to capture with models that treat perfusion with a scalar source term in the bioheat equation.Copyright © 2003 by ASME
The organizational politics of the ASA

The American Sociological Association’s Report on Future Organizational Trends arose from worries that the ASA is disintegrating into a conglomerate of mutually oblivious specialities. The proliferation of sections was regarded as an aspect of this disintegration that the ASA might be able to control. But the committee charged with examining the problem of sections concluded that section expansion has become a major form of political mobilization within the association, and that sections act as a counterweight to the bureaucratic centralization of the ASA as a whole. On balance, the committee opted for the local vitalization going on in sections as against the more abstract concerns of the ASA central governing bodies.
The influence of fatigue stress on the creep behaviour of metals

Abstract A theoretical model, which considers the nature of crystallographic slip in the grain and the heterogeneous stress distribution arised from grain orientations, is proposed for the calculation of cyclic creep behavior of metals. Here the hardening mechanisms which cause the creep rate of slip systems to decrease are generally classified into two broad groups: isotropic, and directional or kinematic; under cyclic deformation the influence of isotropic mechanisms was found to gradually give way to the kinematic mechanisms. An implication of this transition is a softer substructure under cyclic loading, and with the heterogeneous stress field it can also assist the backward dislocation motion, or strain recovery, upon unloading. Indeed, backward dislocation motion and the transition of hardening mechanisms were found to be the major driving forces for cyclic creep acceleration. If this transition takes place too slowly cyclic creep retardation may result. This micromechanical model was applied to study the cyclic creep behavior of a 99.999% pure aluminum. The results, including the effect of fractional unloading, were seen to be in accord with the experimental data.
Frank Parsons: Promoter of a Progressive Era

There is much that cannot be known about Parsons but his life remains both understandable and exemplary to today's students of career development. It is relevant to recall history and to seek explanations regarding the origins of career counseling by considering Parsons as a man in his time. He was a forward thinker and a promoter of the Progressive years. Many of the issues he was concerned with, such as the eight-hour day, profit sharing, the role of education in preparing the citizen for society, urban planning, and ownership of public utilities remain current concerns. His devotion to principle and total dedication to public betterment are qualities which, as Zytowski stated in 1985, remain needed in leaders for our times.