cssi/SciSciGPT-SciSciNet huggingface dataset:
Gatifloxacin and moxifloxacin: an in vitro susceptibility comparison to levofloxacin, ciprofloxacin, and ofloxacin using bacterial keratitis isolates ☆

Abstract Purpose We compared the in vitro susceptibility patterns and the minimum inhibitory concentrations (MICs) of gatifloxacin (GAT) and moxifloxacin (MOX) (fourth-generation fluoroquinolones) to ciprofloxacin (CIP) and ofloxacin (OFX) (second-generation fluoroquinolones) and levofloxacin (LEV; third-generation fluoroquinolone) using bacterial keratitis isolates. The goal was to determine whether the fourth-generation fluoroquinolones offer any advantages over the second- and third-generation fluoroquinolones. Design Experimental laboratory investigation. In contrast to an epidemiologic prevalence study, this study was designed to compare the relative susceptibility of each bacterial group to different fluoroquinolones by deliberate selection of representative isolates that were both susceptible and resistant to second-generation fluoroquinolones. Methods In retrospect, the MICs of 177 bacterial keratitis isolates were determined to CIP, OFX, LEV, GAT, and MOX using E tests. A relative susceptibility analysis was performed for each bacterial group that included separate bacterial groups that were resistant to second-generation fluoroquinolones. The NCCLS susceptibility patterns and the MICs were compared statistically. Comparing MICs, the antibiotic with the lower MICs has greater antibacterial activity. Results For most keratitis isolates, there were no susceptibility differences among the five fluoroquinolones. The fourth-generation fluoroquinolones did, however, demonstrate increased susceptibility for Staphylococcus aureus isolates that were resistant to CIP, LEV and OFX. In general, CIP demonstrated the lowest MICs for gram-negative bacteria. The MICs for fourth-generation fluoroquinolones were statistically lower than the second-generation fluoroquinolones for all gram-positive bacteria tested. Comparing the two fourth-generation fluoroquinolones, MOX demonstrated lower MICs for most gram-positive bacteria, whereas GAT demonstrated lower MICs for most gram-negative bacteria. Conclusions Based on in vitro testing, the fourth-generation fluoroquinolones may offer some advantages over those currently available for the treatment of bacterial keratitis. Clinical studies will be required to confirm these results.
Estimated rates of carbon tetrachloride removal in the thermocline and deep waters of the East Sea (Sea of Japan)

Abstract Dissolved carbon tetrachloride (CCl4) was measured for the first time in the East Sea (Sea of Japan) during the summer of 1999. Fairly high concentrations (> 0.5 pmol kg−1 at the minimum) of CCl4 were observed throughout the water column to the bottom (> 3500 m), with evidence of significant depletion of this compound in the well-oxygenated thermocline waters. CCl4 loss rates below 200 m depth were estimated to range from near zero to 0.05 yr−1 using a tracer-calibrated mixing model, and from 0.04 to 0.07 yr−1 using the CFC-12 partial pressure (pCFC-12) age technique. The results from the mixing model and pCFC-12 age technique are in fairly good agreement in the upper 1500 m of water column, but show systematic differences in the deep waters below 1500 m that are likely due to biases in the pCFC-12 age technique. Despite relatively rapid removal in the upper 500 m water column, the low removal rates for CCl4 in the cold, deep waters of the East Sea estimated using the mixing model ( 2000 m) indicate that this compound can be a potentially useful quantitative ocean tracer in certain regions.
An investigation of the long-run relationship between pollution performance and economic performance: The case of pulp and paper firms

Abstract Studies in environmental economics have tended to examine the impact of pollution performance on economic performance from a macro perspective. Management and accounting studies have focused on the short run. No real consensus has emerged from these studies taken as a whole as to the relationship between pollution performance and economic performance. In this study the economic impact of pollution performance is examined from a micro long-run perspective. Pollution is measured at the plant level and economic performance is measured both using the company as a whole and using just the segment specifically affected by pollution abatement. The analysis is done for both a 6-year and a 9-year time horizon. The association between three measures of pollution performance and five measures of economic performance for the company as a whole is tested using the Spearman rank correlation coefficients. To test the association between the pulp and paper segment and the three measures of pollution, two measures of economic performance were correlated with the pollution measures. The results indicate that the firms were not negatively impacted economically by abating water pollution in their pulp and paper mills. These results do not support the expectation that there would be a negative impact on the economic performance from pollution abatement activities of the firms. These findings are consistent with the finding of earlier studies. Furthermore, it may have policy implications when the US considers future environmental legislation.
Hysteresis properties of titanomagnetites: Grain-size and compositional dependence

Sized fractions of x = 0.6, 0.4, 0.2 and 0.0 titanomagnetites were studied with a vibration magnetometer. In the course particles (d > 150 μm), no compositional dependence of hysteresis parameters was found. HC was less than 50 Oe, HR/HC > 4 and JR/JS < 10−2, reflecting multi-domain behaviour. In contrast, fine particles (d ⋍ 0.1 μm) revealed systematic grain-size dependence of parameters with coercive force as high as 2,000 Oe in x = 0.6 titanomagnetite. Grain-size dependence studies revealed broad transition sizes for the onset of true multi-domain behaviour depending upon which factor is chosen. In magnetite it varies from 10 to 20 μm. The experimental critical size for single-domain behaviour for magnetite is about 0.1 μm and for x = 0.6 titanomagnetite 1–2 μm.
Exploiting Mass Measurements in Different Environments: Density, Magnetic Susceptibility, and Thermogravimetry

The measurement of mass in different surroundings allows one to measure the density of materials and their interaction with magnetic fields or their temperature dependence. Although most curricula cover the use of analytical scales, many leave out mass measurements in different environments. We describe some of the current instrumentation and applications in this area, including a novel and inexpensive method for measuring magnetic susceptibility.
More Evidence of the Need for an Ergonomic Standard

Background In 1999, the Occupational Safety and Health Administration (OSHA) proposed regulations designed to reduce work related inquiries by limiting worker exposure to “ergonomic risk factors.” Congress subsequently overturned the regulations. We provide additional evidence on earnings losses attributable to musculoskeletal disorders (MSDs), and thus on the need for an ergonomic standard. Methods Regression techniques are used to analyze data from a survey of injured workers that has been matched to employer-reported earnings data covering pre- and post-injury periods, and to workers' compensation claims records. Results MSDs lead to large and persistent earnings losses. Cost estimates used by OSHA to justify the 1999 EPS are corroborated. Losses are greatest among workers who file workers compensation claims, but nonclaimants also have losses. Conclusions Earnings losses and lost productivity associated with work-related MSDs are substantial and an ergonomic standard could be cost effective. Am. J. Ind. Med. 45:329–337, 2004. © 2004 Wiley-Liss, Inc.
A sanitary “arc-fixed partial denture”: Concept and technique of pontic design

The design of and rationale for a sanitary arc-fixed partial denture have been described. Reproduction of the anatomic contours of a certain portion of the buccal and lingual surfaces is believed to be responsible for the significant increase in patients' acceptance of this type of pontic design.
Sacral fractures with neurological injury: is early decompression beneficial?

During a 6-year period, 177 patients with a displaced sacral fracture were treated at our level-one trauma centre. At the initial presentation, 13 patients demonstrated a neurological deficit as a result of their sacral fracture. Six patients underwent surgical decompression, and seven patients were managed without surgical decompression. All patients were re-assessed at an average follow-up of 27.1 (range 12–84) months using the modified SOFCOT Index and the SF-36. Patients undergoing surgical decompression had a significantly better neurological improvement as measured by the modified SOFCOT Index (p=0.014). Moreover, patients undergoing surgical decompression had a significantly better physical function than the patients that were managed without surgical decompression, as measured by the SF-36 (p=0.044). We therefore believe that patients undergoing surgical decompression achieve better neurological improvement and better functional results.
On cutoff optimization methods in infinite-dimensional spaces and applications

A general formulation of cutoff optimization methods in infinite-dimensional spaces is given. Various convergence aspects of these methods are proved under general assumptions. The concept of strong and weak convergence is studied. Estimates of convergence rates under certain assumptions are obtained. Applications to optimal control theory and approximation theory are illustrated.
On user criteria for data model evaluation

The emergence of a database technology in recent years has focused interest on the subject of data models. A data model is the class of logical data structures which a computer system or language makes available to the user for the purpose of formulating data processing applications. The diversity of computer systems and languages has resulted in a corresponding diversity of data models, and has created a problem for the user in selecting a data model which is in some sense appropriate to a given application. An evaluation procedure is needed which will allow the user to evaluate alternative models in the context of a specific set of applications. This paper takes a first step toward such a procedure by identifying the attributes of a data model which can be used as criteria for evaluating the model. Two kinds of criteria are presented: use criteria, which measure the usability of the model; and implementation criteria, which measure the implementability of the model and the efficiency of the resulting implementation. The use of the criteria is illustrated by applying them to three specific models: an n-ary relational model, a hierarchic model, and a network model.
Near-field communication-based secure mobile payment service

The loss of customer account information makes headlines all too often. The Payment Card Industry (PCI) Data Security Standard (DSS) has generated resistance from merchants because of its cost and complexity. Unfortunately, innovating in the Point of Sale (PoS) space is hard because the protocols have been standardized, tightly constraining new ideas. Using mobile phones as payment devices opens up some opportunities, but any solution must minimize changes in the back-end processing. This paper describes a Near Field Communication (NFC) based mobile phone payment solution in a service-oriented environment, which provides the needed data protection without requiring costly changes to the payment processing infrastructure. In the payment transaction path, a personal mobile phone is viewed as a single, user-trusted touch point. Compared to other solutions available, our approach better protects user credentials, provides better user control over the transaction, and supports both proximity and remote transactions. The prototype has been integrated with an instore kiosk application and a HP multi-channel banking platform to demonstrate its value in the retail environment.
Transient encephalopathy in a postoperative non-alcoholic female with Marchiafava-Bignami disease

Marchiafava-Bignami disease (MBD) is historically reported in middle-aged alcoholic men. We describe the presentation, course and radiological findings of a young non-alcoholic woman who developed encephalopathy and MRI findings consistent with MBD postoperatively. She returned to baseline after vitamin supplementation. We believe it is important to diagnose MBD because it is a potentially reversible encephalopathy.
Relative fitness models for storage

Relative fitness is a new black-box approach to modeling storage devices. Whereas conventional black-box models train to predict a device's performance given "device-independent" workload characteristics, relative fitness models learn to predict the changes in performance between specific devices. There are two advantages. First, unlike conventional modeling, relative fitness does not depend entirely on workload characteristics; performance and resource utilization (e.g., cache usage) can also be used to describe a workload. This is beneficial when workload characteristics are difficult to express (e.g., temporal locality). Second, because relative fitness models are constructed for each pair of devices, changes in workload characteristics (e.g., I/O inter-arrival delay) can be modeled. Therefore, unlike a conventional model, a relative fitness model can be used by applications with a closed I/O arrival process. In this article, we present relative fitness as an evolution of the conventional model and share some early results.
Equivariant and nonequivariant module spectra

Abstract Let G be a compact Lie group, let RG, be a commutative algebra over the sphere G-spectrumSG, and let R be its underlying nonequivariant algebra over the sphere spectrum S. When RG is split as an algebra, as holds, for example, for RG = MUG. we show how to “extend scalars” to construct a split RG-modale MG = RG ΛR M from an R-module M. We also show how to compute the coefficients M ∗ G in terms of the coefficients R ∗ G , R ∗ , and M ∗ . This allows the wholesale construction of highly structured equivariant module spectra from highly structured nonequivariant module spectra. In particular, it applies to construct MUG-modules from MU-modules and therefore gives conceptual constructions of equivariant Brown-Peterson and Morava K-theory spectra.
Bilingual Experience in the Hungarian and German Immigrant Communities of the San Francisco Bay Area

Studies on the interaction of languages are gaining importance in today’s world, characterized by accelerated migration and increasing cultural exchange. Unlike most research in this field, which concentrate on one embedded language against a matrix language, this fieldwork-based study examines the linguistic life in two immigrant populations, Hungarian and German, against the background of English. The primary focus of this article is the description of the bilingual and bicultural experience of the two groups. The discussion of language and identity will take a central place in the paper, and diglossia, bilingualism, loyalty, and language as social behavior will also be touched upon (section 4). This is complemented by a socio-historical portrayal of these speech communities of San Francisco, set forth in the preceding section 3. Section 5 provides an outline of the informant sets, spanning three generations in each linguistic cohort, and illustrates the subjects’ attitude towards maintenance. The final, sixth section offers qualitative and quantitative comparative statements about the results of linguistic interference and the ongoing attrition process, thus contributing to our understanding of contact linguistic mechanisms, and shedding light on specific grammatical and lexical features that are most prone to attritional forces.
Severe achondroplasia with developmental delay and acanthosis nigricans (SADDAN): Phenotypic analysis of a new skeletal dysplasia caused by a Lys650Met mutation in fibroblast growth factor receptor 3

We previously discovered a novel missense mutation (Lys650Met) in the tyrosine kinase domain of the fibroblast growth factor receptor 3 (FGFR3) gene in four unrelated individuals with a condition we called "severe achondroplasia with developmental delay and acanthosis nigricans" (SADDAN) [Tavormina et al., 1999: Am. J. Hum. Genet. 64:722-731]. Here we present a more detailed clinical account of the SADDAN phenotype. The FGFR3 Lys650Met mutation results in severe disturbances in endochondral bone growth that approach and overlap those observed in thanatophoric dysplasia, type I. However, this mutation is most often compatible with survival into adulthood. Other unusual bone deformities, such as femoral bowing with reverse (i.e., posterior apex) tibial and fibular bowing and "ram's horn" bowing of the clavicle, are also seen in some patients. In addition to skeletal dysplasia, progressive acanthosis nigricans, and central nervous system structural anomalies, seizures and severe developmental delays are observed in surviving SADDAN patients. Despite its location within the same FGFR3 codon as the thanatophoric dysplasia type II mutation (Lys650Glu) and a similar effect on constitutive activation of the FGFR3 tyrosine kinase, the Lys650Met is not associated with cloverleaf skull or craniosynostosis.
Incentive Motivation, Cognitive Control, and the Adolescent Brain: Is It Time for a Paradigm Shift?

It can be argued that adolescents’ decision making is biased more by motivational factors than by cognitively driven calculations of outcome probabilities. Brain-based models, derived from structural and functional neuroimaging perspectives to account for this bias, have focused on purported differences in rates of development of motivational and regulatory-control systems. This article proposes a neurochemically based framework for understanding adolescents’ behavioral biases_and suggests that there should be an increased focus on the dopaminergic substrates of incentive motivation, which increases into adolescence and decreases thereafter. The article also discusses the manner in which this increase interacts with executive control systems in affecting self-regulation.
Parental Social Support, Ethnicity, and Energy Balance-Related Behaviors in Ethnically Diverse, Low-Income, Urban Elementary Schoolchildren

Abstract Objective This study assessed levels of child-reported parent and family social support associated with physical activity (PA) and fruit and vegetable consumption (FVC) by ethnicity among a lower-income sample of US elementary school students. Design Analysis of cross-sectional baseline data of an elementary school–based study from fall, 2010. Setting Nineteen schools in a large urban school district in central Texas. Participants Fourth- and fifth-grade children (n = 581) and their parents. Main Outcome Measures Child-reported parental and family social support, 7-day PA, previous day FVC, and weight status. Analysis Child-reported social support, PA, and FVC using descriptive statistics, ANOVA, chi-square tests, and multiple linear regressions were examined. Results Child-reported parent and family social support varied by ethnicity ( P P Conclusions and Implications Whereas child-reported social support was associated with energy balance–related behaviors across ethnic groups, lower perceived parental and family social support for Hispanic children may represent an important opportunity for intervention.
The state of engrailed expression is not clonally transmitted during early Drosophila development

Abstract In Drosophila embryos, boundaries of lineage restriction separate groups of cells, or compartments. engrailed is essential for specification of the posterior compartment of each segment, and its expression is thought to mark this compartment. Using a new photo-activatable lineage tracer, we followed the progeny of single embryonic cells marked at the blastoderm stage. No clones straddled the anterior edges of engrailed stripes (the parasegment border). However, posterior cells of each stripe lose engrailed expression, producing mixed clones. We suggest that stable expression of engrailed by cells at the anterior edge of the stripe reflects, not cell-intrinsic mechanisms, but proximity to cells that produce Wingless, an extracellular signal needed for maintenance of engrailed expression. If control of posterior cell fate parallels control of engrailed expression, cell fate is initially responsive to cell environment and cell fate determination is a later event.
Expert configuration systems: A survey and lessons learned

Abstract One particular area within expert systems where applications are increasing is configuration management. The need for accurately configuring hardware is an important requirement for many manufacturing organizations. This paper surveys some of the work that is being done in developing expert configuration systems. The paper also presents some lessons learned
Photophoretic modification of the transport of absorbing particles across combustion gas boundary layers

Abstract Since radiation energy fluxes can be comparable to or even dominate ‘convective’ (Fourier) fluxes in large fossil-fuel-fired power stations and furnaces, we examine particle drift (‘phoresis’) induced by the nonuniform photon-produced heating of particles in a ‘host’ gas. Our analysis of the resulting photophoretic particle velocity shows that photophoresis is a significant transport mechanism for micronsized absorbing particles in high radiative transfer combustion environments, with equivalent photophoretic diffusivity ratios (dimensionless photophoretic velocities) being as large as 10% of the better-known thermophoretic diffusivity. Since previous experimental results demonstrated that thermophoresis causes over a 3-decade increase in small particle deposition rates by convective diffusion, clearly, for small, absorbing particles, photophoresis will also be an important contributor to observed deposition rates. Accordingly, we present predicted dimensionless mass transfer coefficients for particle transport across non-isothermal laminar gaseous boundary layers, including the simultaneous effects of both particle thermophoresis and photophoresis. It is also shown that our earlier ‘additive suction velocity’ prediction/correlation scheme successfully anticipates the present numerical (large Schmidt number, laminar boundary layer) results for radiative/conductive flux ratios encountered in practice.
Orientale multi-ringed basin interior and implications for the petrogenesis of lunar highland samples

The lunar Orientale basin is a 900 km diam circular topographic depression covering an area of over 700,000 sq km on the western limb of the moon. Three major rings surround the central Mare Orientale. Orientale basin structures are considered along with Orientale basin deposits and the sequence of formation of structures and deposits. It is found that the structures and facies are related in time and mode of origin to the formation of a major impact crater approximately 620 km in diam. The study suggests that the Orientale basin configuration is very nearly the same as its geometry at its time of formation. The formation of multiringed basins such as Orientale provides a mechanism for an instantaneous production of tremendous volumes of melted lunar crystal material.
Prognostic implications of loss of heterozygosity at 8p21 and 9p21 in head and neck squamous cell carcinoma.

Loss of heterozygosity (LOH) in chromosomal regions that harbor tumor suppressor genes from tumor tissue may lead to decreased survival time in cancer patients with squamous cell carcinoma of the head and neck (HNSCC). We studied 8 regions frequently lost in HNSCC in 150 patients having a primary diagnosis of HNSCC. Tumor and normal tissue DNA were genotyped for microsatellite repeat markers in 8 unlinked chromosomal regions. The association between LOH and death from HNSCC was investigated, weighted by number of informative markers per region and adjusted for age at diagnosis, self-reported race, tumor stage and current smoking status. LOH at 3 chromosomal regions were independently associated with reduced survival. A greater risk for cancer mortality was observed for LOH at chromosomal regions 3p24.3-p14.3 (p = 0.02), 8p21.3-p11.21 (p = 0.02) and 9p24.2-p21.2 (p = 0.03). In these regions, LOH at one or more markers was observed in 66.9%, 43.3% and 60.6% of patients, respectively. Survival times were significantly shorter for those with LOH at marker NEFL on 8p21.2 (relative risk = 6.15; p = 0.0002) and at D9S126 on 9p21.2 (relative risk = 5.96; p = 0.0003). Our results indicate that LOH at several chromosomal sites may offer additional independent prognostic information beyond traditional indicators such as tumor stage and age. © 2004 Wiley-Liss, Inc.
Turbofan engine database as a preliminary design tool

Abstract A large database of currently manufactured turbofan engines with a bypass ratio of at least 2.0 was compiled in 1996. Key parameters (dry weight, length, fan diameter, nacelle diameter, cruise thrust, air mass flow, bypass ratio, total pressure ratio, take-off specific fuel consumption, and cruise specific fuel consumption) were plotted, most as a function of take-off thrust. The resulting plots are a rich source of basic information, which can be used to quickly define an engine for use in a preliminary airplane design. The database is sorted by take-off thrust and can also be used to determine if an existing engine can be used in the proposed airplane. Relationships are suggested for use in preliminary design.
Head Waves as Mechanism for Azimuthal PP AVO Magnitude Anomalies

Summary We performed physical seismic modeling experiments to simulate seismic reflections off the top of an anisotropic fracture model with horizontal transverse symmetry (HTI). Our study examined the role that head waves play in the anomalous PP AVO magnitudes for reflection data shot at different (inline) azimuth with respect to the general fracture direction. We show that head waves occur at different critical offsets/angles depending on the direction by which seismic waves are incident on the plane of the HTI model (i.e. the fracture plane direction). Specifically, head waves occur at greater offsets or wider critical angle as the shooting inline becomes more perpendicular to fractures.
Health status as a potential mediator of the association between hemodialysis vascular access and mortality

Background It is unknown whether the selection of healthier patients for arteriovenous fistula (AVF) placement explains higher observed catheter-associated mortality among elderly hemodialysis patients. Methods From the United States Renal Data System 2005-2007, we used proportional hazard models to examine 117 277 incident hemodialysis patients aged 67-90 years for the association of initial vascular access type and 5-year mortality after accounting for health status. Health status was defined as functional status at dialysis initiation and number of hospital days within 2 years prior to dialysis initiation. Results Patients with catheter alone had more limited functional status (25.5 versus 10.8% of those with AVF) and 3-fold more prior hospital days than those with AVF (mean 18.0 versus 5.4). In the unadjusted model, the likelihood of death was higher for arteriovenous grafts (AVG) {Hazard ratio (HR) 1.20 [95% CI (1.16-1.25)], catheter plus AVF [HR 1.34 (1.31-1.38)], catheter plus AVG [HR 1.46 (1.40-1.52)] and catheter only [HR 1.95 (1.90-1.99)]}, compared with AVF (P . Conclusions The observed attenuation in mortality differences previously attributed to access type alone suggests the existence of selection bias. Nevertheless, the persistence of an apparent survival advantage after adjustment for health status suggests that AVF should still be the access of choice for elderly individuals beginning hemodialysis until more definitive data eliminating selection bias become available.
PECAM-1 interacts with nitric oxide synthase in human endothelial cells: implication for flow-induced nitric oxide synthase activation.

Objective— We have previously shown that fluid shear stress (FSS) triggers endothelial nitric oxide synthase (eNOS) activity in endothelial cells and that the mechanotransduction mechanisms responsible for activation discriminate between rapid changes in FSS and FSS per se. We hypothesized that the particular sublocalization of eNOS at the cell–cell junction would render it responsive to activation by FSS temporal gradients. Methods and Results— In human umbilical vein endothelial cells (HUVECs), immunofluorescence revealed strong eNOS membrane staining at the cell–cell junction colocalizing with platelet/endothelial cell adhesion molecule-1 (PECAM-1). In PECAM-1 −/− mouse aorta, eNOS junctional localization seen in the wild type was absent. Similarly, junctional staining was lost in wild-type aorta near intercostal artery branches. eNOS/PECAM-1 association in HUVECs was confirmed by coimmunoprecipitation. When HUVECs were subjected to a 0.5s impulse of 12 dynes/cm2, a transient disruption of the eNOS/PEC...
A new framework for QoS provisioning in WLANS using p-persistent 802.11 MAC

In this paper, we propose a new framework which consists of three components viz., a p-persistent 802.11-based core MAC layer which provides optimum channel utilization, a scheduler that provides service differentiation between different classes of traffic in the contention phase of 802.11 and an admission control which provides statistical QoS guarantees. The current 802.11e EDCF protocol uses the same set of parameters viz., CW"m"i"n, CW"m"a"x, CW, AIFS, and PF for both channel access and service differentiation. We show that using these parameters to achieve a specific desired throughput differentiation is a very cumbersome task. We present detailed performance results of our framework using the NS2 simulator to demonstrate the effectiveness of the scheduler and the core MAC layer. Compared to 802.11 adaptive EDCF, our scheduler consistently achieves the desired throughput differentiation and easy tuning. The core MAC layer achieves better delays in terms of channel access, average packet service time and one hop delay and also achieves higher system throughput than the AEDCF for a given service differentiation ratio. We also develop an analytical model for the p-persistent 802.11 in the core MAC layer under unsaturated load conditions and present closed forms for the average packet service time and one hop delay. We consider both the ''no retry limit'' and ''finite retry limit'' cases and validate the analytical model by extensive simulation results.
Disk drive control: The early years

Abstract One of the persistently exciting control applications is that of disk drive servos. From the start in the early 1950s to the massive capacity commodity drives of the early 2000s, the problem of accessing data on rotating disk media has provided a wealth of control challenges to be solved. This survey paper traces the early history of disk drive control from the first disk drive in 1956 to the first commercial drive with Magneto-Resistive heads in 1990. Rather than the approach used in (Abramovitch and Franklin, 2002 a ) in which the histories of the components were outlined first, we will focus on the feedback loop itself in those early days. The paper will survey the different areas of the disk drive control problem and how they evolved.
Query processing in LDV: a secure database system

An overview is given of the query processing of the multilevel secure database management system (MLS/DBMS), LOCK Data Views (LDV), for the secure distributed Data Views contract. The authors summarize design issues such as data distribution, polyinstantiation, and response assembly. They show the need for a security policy for a database system that builds on the classical security policies for operating systems. They describe some of the problems associated with multilevel databases and their approach to solving them. They also explain how a pipeline organization helps to minimize the amount of design and code that must be trusted and/or verified. >
On behavioral modeling of analog and mixed-signal circuits

Behavioral simulation of complex, inherently highly nonlinear mixed-signal systems is often the only effective way to evaluate possible system performance before fabrication and characterization of the hardware system. Transistor-level, SPICE, simulations of these systems are often practically impossible because of the enormous computational time required due to the many interactions of all the nonlinearities and the widely separated system time constants. New behavioral models for useful electronic functions have been developed as straightforward mathematical descriptions that can be evaluated by general purpose mathematical programs and system simulators. The models are targeted for MATLAB and use standard MATLAB expressions and linked C and FORTRAN codes. An example PLL behavioral model is presented and evaluated by comparing simulated performance to actual experimental integrated circuit performance. >
Phase-Phase and Phase-Neutral Switching Surges on 500-kV Open-Ended Lines

System insulation requirements on EHV systems, especially above 345 kV, are predominantly a function of switching surge overvoltages. Modem lightning arrester and circuit breaker technology and increased knowledge and understanding of insulation systems relative to switching surges have allowed substantial economics at higher transmission levels.
Algorithms to determine the edges of a convex hull from its vertices

Trying to develop a fast algorithm that finds all the edges of a convex hull produced three different ideas. The analysis of these resulted in geometric and theoretical findings. One of the contributions of this paper is to describe the three algorithms. The dissemination of the geometric insights and the theory developed is also a contribution. Since one of the objectives is execution speed, the paper presents the results of a computational analysis. The article reports on the algorithms’ theoretical complexity and computational performance. This includes a comparison among themselves and against the best available algorithm for the same problem. Two of the new algorithms are efficient, especially in the case of large scale problems. The paper also explains that these algorithms can be accelerated by means of well-known speed-up techniques. Implementing an output sensitive algorithm by Dula and Lopez (2006) into one of the new algorithms produced the fastest approach.
Assessing the Role of Local Communication Networks in Neighborhood Disorder and Crime

This study conceptualizes local communication networks as a unique source of neighborhood collective efficacy. Data from the Seattle Neighborhoods and Crime Survey were used to create neighborhood-level measures of structural factors, friendship/kinship networks, organizational participation, local communication networks, collective efficacy, disorder, and crime victimization. Results indicate that socioeconomic status and residential stability have positive effects on local communication networks. The measure of local communication networks is positively related to collective efficacy, which in turn has decreased effects on disorder and crime victimization. Implications are discussed in terms of the role of communication in building a safe community.
The Detectability of Local Deviations from a Typical Expressive Timing Pattern

In three experiments, musically trained listeners tried to detect local deviations from a typical pattern of expressive timing in the initial measures of Chopin9s Etude in E Major. The goal of the experiments was to neutralize structurally based perceptual biases ("timing expectations") that had been revealed previously in the detectability of local deviations from metronomic timing in the same music. In Experiment 1, which presented deviations from full-scale expressive timing, the perceptual biases were reversed, indicating that listeners9 timing expectations were smaller than the typical timing variation in performance. Experiments 2 and 3 therefore presented deviations from a down-scaled timing pattern (25% or 10% of its original magnitude). Although neither experiment succeeded in completely neutralizing the perceptual biases, correlational evidence suggested that listeners9 timing expectations were about five times smaller than typical expressive timing variations. The small, essentially subliminal size of the listeners9 timing expectations is consistent with recent findings of related unintentional timing variation in deliberately metronomic performance and in finger-tap synchronization with a metronomic rendition of the same music.
Application of Smart Structures to Aircraft Health Monitoring

Research efforts at Innovative Dynamics have produced sensors and signal processing software that can be integrated into an advanced Health Monitoring System (HMS) to increase the safety of aging aircraft. HMS is a unique distributed system based on "smart structures" technology. By monitoring the vibration signature of a structure, HMS determines structural abnormalities using a network of sensor arrays and distributed processors. Pattern recognition techniques are utilized to classify the sensor signals and determine the type of defect. The memory of the system is formed through a learning pro cess in which a systematic series of experiments is presented to the system.
Control Selection and Participation in an Ongoing, Population-based, Case-Control Study of Birth Defects The National Birth Defects Prevention Study

To evaluate the representativeness of controls in an ongoing, population-based, case-control study of birth defects in 10 centers across the United States, researchers compared 1997-2003 birth certificate data linked to selected controls (n = 6,681) and control participants (n = 4,395) with those from their base populations (n = 2,468,697). Researchers analyzed differences in population characteristics (e.g., percentage of births at > or =2,500 g) for each group. Compared with their base populations, control participants did not differ in distributions of maternal or paternal age, previous livebirths, maternal smoking, or diabetes, but they did differ in other maternal (i.e., race/ethnicity, education, entry into prenatal care) and infant (i.e., birth weight, gestational age, and plurality) characteristics. Differences in distributions of maternal, but not infant, characteristics were associated with participation by selected controls. Absolute differences in infant characteristics for the base population versus control participants were < or =1.3 percentage points. Differences in infant characteristics were greater at centers that selected controls from hospitals compared with centers that selected controls from electronic birth certificates. These findings suggest that control participants in the National Birth Defects Prevention Study generally are representative of their base populations. Hospital-based control selection may slightly underascertain infants affected by certain adverse birth outcomes.
FIRST “Winged” and X-Shaped Radio Source Candidates

A small number of double-lobed radio galaxies are found with an additional pair of extended low surface brightness 'wings' of emission giving them a distinctive 'X'-shaped appearance. One popular explanation for the unusual morphologies posits that the central supermassive black hole (SMBH)/accretion disk system underwent a recent realignment; in a merger scenario, the active lobes mark the post-merger axis of the resultant system (e.g., Merritt & Ekers 2002). However, this and other interpretations are not well tested on the few (about one dozen) known examples. In part to remedy this deficiency, a large sample of winged and X-shaped radio sources is being compiled for a systematic study. An initial sample of 100 new candidates is described as well as some of the follow-up work being pursued to test the different scenarios.
Arl2 and Arl3 regulate different microtubule-dependent processes.

Arl2 and Arl3 are closely related members of the Arf family of regulatory GTPases that arose from a common ancestor early in eukaryotic evolution yet retain extensive structural, biochemical, and functional features. The presence of Arl3 in centrosomes, mitotic spindles, midzones, midbodies, and cilia are all supportive of roles in microtubule-dependent processes. Knockdown of Arl3 by siRNA resulted in changes in cell morphology, increased acetylation of α-tubulin, failure of cytokinesis, and increased number of binucleated cells. We conclude that Arl3 binds microtubules in a regulated manner to alter specific aspects of cytokinesis. In contrast, an excess of Arl2 activity, achieved by expression of the [Q70L]Arl2 mutant, caused the loss of microtubules and cell cycle arrest in M phase. Initial characterization of the underlying defects suggests a defect in the ability to polymerize tubulin in the presence of excess Arl2 activity. We also show that Arl2 is present in centrosomes and propose that its action in regulating tubulin polymerization is mediated at centrosomes. Somewhat paradoxically, no phenotypes were observed Arl2 expression was knocked down or Arl3 activity was increased in HeLa cells. We conclude that Arl2 and Arl3 have related but distinct roles at centrosomes and in regulating microtubule-dependent processes.
Effect of chirality on the transient signal wave front

We analyze the behavior of the wave front of a transient pulse propagating in an isotropic homogeneous chiral material and discuss the role of chirality and its underlying physics on the pulse’s rise time, ringing frequency at the early time of arrival, and state of polarization at the wave front. We use the one-resonance model of dispersion for the material parameters. It is shown that the chirality of the medium decreases the ringing frequency at the early time as compared with the nonchiral case and causes the rotation of the plane of polarization and the evolution of the cross-polarized component at the transient signal wave front. Potential applications and motivations for the present study are also mentioned.
Army's Activities In Artificial Intelligence/Robotics

A historical summary of the Army activities in artificial intelligence and robotics (AI/R) in the last one and one-half years indicates Army interest in AI/R from the laboratories to the Secretariat. Numerous funded and unfunded efforts are now planned by the laboratories even though AI/R technologies lack maturity necessary for autonomous battlefield systems in the 1990's. The potential applications of AI/R systems to Army needs appear to be limitless. DARCOM and TRADOC have prioritized AI/R requirements and plans for five high priority Demonstrators have been prepared. These demonstrators reflect the need to get started with todays technologies. Technological enhancements provided by additional research and development can provide additional autonomy in product improvement phases of the system development cycle.© (1983) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Efficient Reductions for Imitation Learning

Imitation Learning, while applied successfully on many large real-world problems, is typically addressed as a standard supervised learning problem, where it is assumed the training and testing data are i.i.d.. This is not true in imitation learning as the learned policy influences the future test inputs (states) upon which it will be tested. We show that this leads to compounding errors and a regret bound that grows quadratically in the time horizon of the task. We propose two alternative algorithms for imitation learning where training occurs over several episodes of interaction. These two approaches share in common that the learner’s policy is slowly modified from executing the expert’s policy to the learned policy. We show that this leads to stronger performance guarantees and demonstrate the improved performance on two challenging problems: training a learner to play 1) a 3D racing game (Super Tux Kart) and 2) Mario Bros.; given input images from the games and corresponding actions taken by a human expert and near-optimal planner respectively.
Primary Attraction of the Mountain Pine Beetle to Lodgepole Pine in Oregon

Dispersing Dendroctonus ponderosae landed preferentially on lodgepole pines with fire scars and decay ( P = 0.023 and P = 0.008, respectively, by joint binomial distribution analysis).
Adaptive heave compensation via dynamic neural networks

This paper discusses the problem of adaptive heave compensation. A new estimator based on dynamic recurrent neural networks is applied to this problem. It is shown that the new algorithm is well suited for online implementation and has excellent performance. Computational results via extensive simulations are provided to illustrate the effectiveness of the algorithm. A comparative evaluation with conventional methods is also provided. >
Nucleosides. CXLIX. Novel and practical synthesis of alpha-monofluoro- and alpha,alpha-difluorothymidine (F-TDR and F2-TDR).

Di-O-tert-butyldiphenylsilyl (BDPS)-thymidine (2) was converted to α-bromo-3', 5'-di-O-BDPS-thymidine (3) by photobromination. Crude 3 was hydrolyzed to the α-hydroxythymidine derivative 4 which was oxidized with MnO2 to the 5-formyluracil nucleoside 5. Fluorination of 4 with diethylamino-sulfur trifluoride afforded the protected α-fluorothymidine 6. Similarly, 5 was converted into the α, α-difluorothymine nucleoside 7. These protected fluorothymidines (6 and 7) were deblocked by treatment with tetra-n-butylammonium fluoride to give α-fluorothymidine(8, F-TDR) and α, α-difluorothymidine (9, F2-TDR).
Bombieri's mean value theorem

The purpose of this paper is to give a short proof of an important recent theorem of Bombieri [2] on the mean value of the remainder term in the prime number theorem for arithmetic progressions. Applications of the theorem have been made by Bombieri and Davenport [3], Rodriques [9], and Elliott and Halberstam [5]. For earlier versions of the theorem and a survey of other applications, see Barban [1], and Halberstam and Roth [7, Chapter 4].
Allogeneic blood transfusion and postoperative duration of mechanical ventilation: effects of red cell supernatant, platelet supernatant, plasma components and total transfused fluid

Background and Objectives In patients undergoing open-heart surgery, allogeneic blood transfusion (ABT) may be related to an enhanced inflammatory response and impaired pulmonary function, resulting in a need for prolonged mechanical ventilation. Transfused red blood cell (RBC) supernatant, platelet supernatant or plasma components, may exercise varying effects on pulmonary function, because these fluids differ in their content of soluble biological-response modifiers. Materials and Methods The records of 416 patients undergoing coronary artery bypass graft operations at the Massachusetts General Hospital were reviewed. Possible predictors and the number of days of postoperative ventilation, as well as the number of all transfused blood components, were recorded. The association between mechanical ventilation past the day of operation and the volume of transfused RBC supernatant, platelet supernatant, or plasma components, was calculated by logistic regression analyses. Results The volume of each transfused fluid differed (P < 0·0001) among patients ventilated for 0, 1, 2, 3, or ≥ 4 days after the day of the operation. After adjusting for the effects of confounding factors, the volume of administered RBC supernatant was associated (P = 0·0312) with the likelihood of postoperative ventilation past the day of operation, but the volume of platelet supernatant, plasma components, or total transfused fluid was not (P = 0·1528, P = 0·1847, and P = 0·0504, respectively). Conclusions These results are congruent with the hypotheses that ABT may impair postoperative pulmonary function and that any such adverse effect of ABT is probably mediated by the supernatant fluid of stored RBCs. Both hypotheses should be examined further, in future studies of the outcomes of ABT.