cssi/SciSciGPT-SciSciNet huggingface dataset:
Clarification of an index nannofossil species for the Paleocene/Eocene boundary

The first occurrence of Discoaster diastypus Bramlette and Sullivan is a marker for the CP8/CP9 zonal boundary in the widely used nannofossil zonation of Okada and Bukry (1980). This zonal boundary has commonly been used to approximate the Paleocene/Eocene boundary (e.g., Berggren et al., 1985; Perch-Nielsen, 1985). In spite of the frequent use and importance of D. diastypus in biostratigraphy, there has been some confusion about this species in the literature, including some of the most used references. For instance, Bramlette and Sullivan (1961), who first described the species, incorrectly defined D. diastypus in terms of its ray number and size (see Figure 1), and included a specimen of Discoaster falcatus Bramlette and Sullivan as an isotype of D. diastypus (Bramlette and Sullivan, 1961, pi. 11, fig. 6). Perch-Nielsen (1971, pi. 51, figs. 8 and 10) figured a specimen of Discoaster barbadiensis Tan and another specimen of Discoaster bifax Bukry as D. diastypus . These mistakes apparently have gone unnoticed and were adopted by Romein (1979, p. 168) and incorporated in the Handbook of Cenozoic Calcareous Nannoplankton (Aubry, 1984, p. 46, fig. 111; p. 48, figs. 114 and 115).
Computer Aided Diagnosis in Mammography: Its Development and Early Challenges

This article discusses the development of a technology of "computer vision" designed to assist medical practitioners diagnosing breast cancer in the 1980s and 1990s. A CAD system was designed to augment human vision by digitizing mammograms, enhancing computer-selected "regions of interest" and offering a protocol to recommend a course of action (follow up examination, biopsy, etc.). One issue that emerged following the introduction of CAD was that human vision - previously the "gold standard" for diagnostic accuracy - was influenced by the prompts the computer provided the interpreter, illuminating the paradoxes of de-skilling and the problems mediating visualization and expert decision making.
Review of Basic Background

In this chapter we review some of the basic ideas of matrix theory. It is assumed that the reader is (or was at one time) familiar with the contents of this chapter, or at least most of it, and a rather quick reading will serve to recall these basic facts as well as to establish certain notation that will be used in the remainder of the book. Some of the topics covered, especially linear equations and eigenvalues, will be expanded upon later in different ways.
Self-Efficacy and Psychological Ownership Mediate the Effects of Empowering Leadership on Both Good and Bad Employee Behaviors

This study examined the potential effects of empowering leadership on followers’ in-role performance and deviant behaviors via self-efficacy and psychological ownership over a 3-week period in a sample of 299 full-time employees working in the United States. Results from structural equation modeling demonstrated that empowering leadership was positively related to both self-efficacy and psychological ownership, which in turn were both negatively related to deviant behaviors. Alternative model comparisons and bootstrapping both confirmed the mediation effects of self-efficacy and psychological ownership. However, only one of the two mediators, self-efficacy, was positively related to followers’ in-role performance. Together, these findings highlighted the important roles of self-efficacy and psychological ownership explaining why empowering leadership may result in followers’ behaviors.
Learning the Language: The Importance of Studying Written Directions in Designing Navigational Technologies for the Blind

Independent navigation is important to individuals who are blind and visually impaired (VI). Researchers have long explored how blind and VI people navigate to inform the design of more useful, accessible wayfinding devices. However, there has been little research on the role language plays in providing effective Text-to-Speech directions for this population. In this paper, we investigate the language and cues expressed in written navigational directions exchanged between blind and VI members of a Yahoo! Group mailing list. Through qualitative analysis, we unpack the types of and frequencies of information exchanged, including how distances are represented, how direction is indicated, and what landmarks are referenced. We notably found that written directions often included warnings about when a navigator may have gone too far, which alternate routes are easier to navigate, and how welcoming and accessible destinations might be for people with disabilities.
mTORC1 promotes Schwann cell cycling and myelinogenesis

Schwann cells (SCs), the glial cells of the peripheral nervous system (PNS), protect axons and enwrap them with multilayered myelin sheaths that facilitate saltatory nerve conduction.1 Myelin synth...
Israeli View of the Obama Era: A Relationship Reexamined

The Obama era symbolized an unprecedented downward spiral in US–Israeli relations. In the short term, one can attribute the deterioration to the difficult, at times impossible, relationship between Obama and Netanyahu, who shared different political worldviews. Washington and Jerusalem clashed over the Israeli–Palestinian peace process and what to do with Iran’s nuclear program. However, these tensions did not appear to have had any impact on the US’s commitment to Israeli security or on its view of Israel as an important strategic ally. In the long run, however, the Obama era signals a shift in US demographics that is likely to have electoral consequences in the future. As a result, the “special” relationship may be “special” no more as changing public attitudes afford the US the freedom of political action to distance itself from, and at time even collide with, Israeli policies as Obama had done.
Spurious Hyperchloremia in the Presence of Elevated Plasma Salicylate: A Cohort Study.

Background Acute metabolic acidosis is rarely associated with a reduced or negative anion gap (AG), but several case reports have described such an abnormality occurring in the setting of acute salicylate intoxication. The underlying cause of this phenomenon is unclear. Methods In this retrospective cohort study, we reviewed our institutional database to identify all patients admitted for salicylate intoxication at Mayo Clinic (Rochester, MN, USA) from January 2010 through December 2012. Serum chloride was measured with the Cobas INTEGRA 400 plus electrode (expedited laboratory test) or Cobas 6000 (routine laboratory test). We compared blood chloride levels measured by the 2 devices in the presence of positive blood salicylate level. Results Twelve adult patients with salicylate levels >20 mg/dL had markedly elevated chloride concentrations. The median (interquartile range) chloride level at admission was 120 (107-145) mmol/L on their initial laboratory studies, resulting in reduced or even negative AGs. None of the patients had bromide toxicity, nor did they have any other identifiable cause of hyperchloremia or decreased AG. Further testing of the same blood samples with an alternative measurement system (Roche Cobas 6000) yielded normal chloride values, indicating that falsely elevated chloride values with the initial testing led to the diminished or negative AG values. Conclusion Circulating levels of salicylate can interfere with chloride measured by using routine techniques, resulting in spurious hyperchloremia outcomes and erroneous AG values. In patients with acute metabolic acidosis and abnormally reduced or negative AG, salicylate interference with chloride measurement should be suspected.
A LabVIEW based test system to characterize phasor measurement units

Phaser measurement units (PMUs) have become indispensable elements of a reliable power system network and the ability to make precise time synchronized measurements with the best possible accuracy have made these devices to be the best choice for wide area operation, protection and control in a large power system. Due to the widespread use of synchrophasor measurements, it becomes necessary to characterize each PMU based on their performance and select the appropriate device for the required application. Furthermore, the IEEE Std C37.118.1a-2014 mandates the latest performance standards for the commercial PMUs and classifies them based on their performance. This necessitates the development of a test-bed which is capable of testing different PMUs to check whether they comply with the latest IEEE standard and also to characterize the devices in terms of their accuracy and precision. This paper describes a LabVIEW based PMU testing and calibration system that was developed at Virginia Tech with the support of NIST and is capable of performing the latest steady state, dynamic and latency tests as described in the IEEE Synchrophasor standard. The testing system also provides flexibility by automatic and manual modes of operation to allow the characterization of PMUs based on the requirements of the test operator.
Brain Stem Gliomas in Children

Brain tumors are the most common solid tumors and second most common malignancies in children after the leukemias. Approximately 1100–1200 new cases of brain and central nervous system tumors are seen yearly in children under the age of 14 in the United States. Brain stem tumors account for 10%–20% of all brain tumors in children (Abramson et al. 1974; Littman et al. 1980; Bloom et al. 1990). For the purposes of this chapter, brain stem will be defined as the medulla oblangata and the pons and will exclude the thalamus and midbrain. No sex or racial predominance is noted in brain stem gliomas. The mean age at diagnosis varies from 6.5 to 8.9 years (Halperin 1985; Freeman and Suissa 1986; Eifel et al. 1987; Freeman et al. 1987; Stroink et al. 1987; Halperin et al. 1989b; Shrieve et al. 1992).
Mineral Homeostasis and Effects on Bone Mineralization in the Preterm Neonate

Most bone formation and mineralization occurs late in gestation. Accretion of adequate minerals is a key element of this process and is often interrupted through preterm birth. In utero, mineral transport is accomplished via active transport across the placenta and does not require fetal hormone input. Postnatal mineral homeostasis requires a balance of actions of parathyroid hormone, calcitonin, and vitamin D on target organs. Preterm birth, asphyxia, acidosis, and prolonged parenteral nutrition increase the risk of mineral imbalance and metabolic bone disease (MBD). Aggressive postnatal nutrition is key to preventing and treating MBD in preterm infants.
Statin use and pancreatic cancer risk in two prospective cohort studies.

Statins, 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors, are common lipid-lowering agents and may reduce the risk of several cancer types including pancreatic cancer. However, the association between statin use and pancreatic cancer risk has not been fully evaluated in prospective studies. We studied the association between statin use and incident pancreatic cancer in 113,059 participants from the prospective Nurses’ Health Study and Health Professionals Follow-up Study. Statin use was self-reported via study questionnaires and updated biennially. Hazard ratios (HRs) and 95% confidence intervals (CIs) for incidence of pancreatic cancer were estimated using multivariable Cox proportional hazards models with adjustment for potential confounders. In total, 583 participants developed incident pancreatic cancer during 1.4 million person-years of follow-up. No difference was identified in pancreatic cancer risk for regular versus non-regular statin users (multivariable-adjusted HR 0.98; 95% CI 0.82–1.16). There was no significant heterogeneity in the association of statin use with pancreatic cancer risk between the cohorts. Similarly, longer duration of regular statin use was not associated with decreased risk of pancreatic cancer (Ptrend = 0.65). The results remained similar when we examined statin use status at baseline or accounting for 4-year latency period. We observed no statistically significant effect modification for the association of statin use with pancreatic cancer risk by body mass index, smoking status, or diabetes mellitus status (all Pinteraction > 0.21). Regular statin use was not associated with pancreatic cancer risk in two large prospective cohort studies in the U.S.
Types I and II Keratin Intermediate Filaments

Keratins-types I and II-are the intermediate-filament-forming proteins expressed in epithelial cells. They are encoded by 54 evolutionarily conserved genes (28 type I, 26 type II) and regulated in a pairwise and tissue type-, differentiation-, and context-dependent manner. Here, we review how keratins serve multiple homeostatic and stress-triggered mechanical and nonmechanical functions, including maintenance of cellular integrity, regulation of cell growth and migration, and protection from apoptosis. These functions are tightly regulated by posttranslational modifications and keratin-associated proteins. Genetically determined alterations in keratin-coding sequences underlie highly penetrant and rare disorders whose pathophysiology reflects cell fragility or altered tissue homeostasis. Furthermore, keratin mutation or misregulation represents risk factors or genetic modifiers for several additional acute and chronic diseases.
The Creep Buckling of a Double Membrane Spherical Shell

A simple model study is carried out and is followed by an analysis of the axisymmetric creep buckling of a complete spherical shell under external pressure. The Norton-Bailey constitutive equations are used to describe the secondary creep behavior and elastic effects are retained. The shell is considered to be initially imperfect with an imperfection in the shape of the classical buckling mode. The wall of the shell is replaced by a double membrane (“sandwich”) wall in the analysis. The problem is formulated using the Donnel–Mushtari–Vlasov equilibrium and kinematic equations appropriately modified to include the influence of initial stress-free imperfections in the radius. A perturbation scheme is used to solve the equations and closed form expressions for the radial and tangential deflections as a function of time are obtained. Results are compared with predictions from a finite-difference model and are found to yield a very good estimate of the deformation behavior when the initial imperfection is small.
The Ocular Motor System: Normal and Clinical Studies

In order to give an appropriate overview of our clinical studies in the ocular motor system and to exemplify the close interaction of the clinician and the bioengineer, we will provide a review of the work of the Miami ocular motor neurophysiology laboratory, including studies on subjects and patients and the implications they hold for the control of eye movements.
Surveying ADR Knowledge and Practices Among US Gastroenterologists.

BACKGROUND The adenoma detection rate (ADR) is of primary importance to the quality of screening colonoscopy. An online survey was conducted to assess knowledge and practices on ADR. METHODS Paid questionnaire distributed by email. Eligible respondents were board certified gastroenterologists who perform >80 colonoscopies per month with 3 to 35 years practice after fellowship. RESULTS There were 250 respondents. In total, 39% were unaware that ADR applies only to screening colonoscopies and 76% incorrectly answered that ADR includes sessile-serrated polyps/adenomas. A total of 51% of respondents incorrectly believe the threshold is set at 25% because 25% is a national ADR average. Many also believe the threshold depends on the patient population (current evidence suggests adjusting ADR for factors other than age and sex is unnecessary). 75% ranked ADR as highly important. 80% reported tracking ADR. A busy practice was the most common reason for not tracking ADR. Caps, chromoendoscopy, and good bowel preparation were viewed as valuable for improving ADR (this is true except for caps). High-definition colonoscopes and education were considered less valuable, despite evidence indicating that both are associated with improved ADR. In total, 57% reported not sharing ADR information with their patients, and 59% reported that no patients in the last 6 months asked for their ADR. CONCLUSIONS The importance of ADR as a quality measure is well understood, but there are misconceptions among gastroenterologists regarding the definition and measurement of ADR, and which methods are proven to increase ADR. Patients are having very little impact on ADR measurement.
Radiographically Occult Symptomatic Lunotriquetral Coalition in a Child.

Carpal coalitions are congenital segmentation anomalies with an abnormal union of one or more carpal bones. They can be broadly classified as osseous or non-osseous and as partial or complete. Lunotriquetral coalitions are the most common type of carpal coalition and are typically asymptomatic and detected incidentally. However, there are several case reports and small case series reporting symptomatic non-osseous lunotriquetral coalitions, which show findings on radiographs. This is a report of a case of a child with a symptomatic non-osseous lunotriquetral coalition which was undetected on initial radiographs but diagnosed on a subsequent wrist magnetic resonance imaging (MRI).
A probabilistic framework to incorporate mixed-data type features: Matrix factorization with multimodal side information

Abstract Recommender systems that exclusively rely on past interactions between the users and the items underperform in settings with very few observations. Their performance at such extreme sparsity can be improved by exploiting the side information of the users and the items including the demographics and the item descriptions. However, such side information is mostly heterogeneous and multimodal, including both numerical and categorical features to yield a non-trivial incorporation process. Researchers have addressed this problem mainly by converting the categorical features into numerical ones or forming numerical similarity matrices. This paper presents a different approach in the form of a novel Bayesian probabilistic generative framework which can effectively incorporate multimodal side information into the matrix factorization (MF-MSI) model. With the help of local quadratic bounds on the categorical likelihoods, we derive a scalable and computationally efficient iterative optimization method based on the variational EM to learn the posterior distributions of latent variables for both the users and the items. A comprehensive experimental study on both simulated and real benchmark datasets demonstrate the proof-of-concept where the additional side information improves both the prediction accuracy and the ranking performance over more than a dozen popular baseline models. Finally, the proposed MF-MSI model claims state-of-the-art performance in the majority of the test scenarios when compared to more recently introduced recommender systems which can also utilize the side information via different techniques.
Effect of Unit Operations Laboratory Course Structure on Learning and Self-Efficacy.

A unit operations laboratory course was significantly modified to be an open-ended problem-based experience with an emphasis on teamwork and communication skills. Students were surveyed to assess gains in engineering self-efficacy as well as to indicate which course structure components were most beneficial to learning. Students showed significant gains in communication and design self-efficacy. Lectures were rated unimportant, while lab reports, oral presentations, teamwork, and open-ended problems were rated as highly important for learning.
Nonchaotic Models and Predictability of the Users' Volume Dynamics on Internet Platforms

Internet platforms' traffic defines important characteristics of platforms, such as price of services, advertisements, speed of operations. The traffic is usually estimated with the help of the traditional time series models (ARIMA, Holt-Winters, etc.), which are successful in short term extrapolations of sufficiently denoised signals. We propose a dynamical system approach for the modeling of the underlying process. The method allows to discuss the global qualitative properties of the dynamics' phase portrait and long term tendencies. The proposed models are nonchaotic, the long term prediction is reliable, and it explains the fundamental properties and trend of various types of digital platforms. Because of these properties, we call the flow of these models the {\it trending flow}. Utilizing the new approach, we construct the two-sided platform models for the volume of users, that can be applied to this http URL, this http URL or this http URL. We consider a generalization of the two-sided platforms' models to multi-sided platforms. If the equations' are cooperative, the flow is trending, and it helps to understand the properties of the platforms and reliably predicts the long term behavior. We show how to reconstruct the governing differential equations from time series data. The external effects are modeled as system's parameters (initial conditions).
Effects of Routine Checkups and Chronic Conditions on Middle-Aged Patients with Diabetes.

Purpose. Middle-aged males and females with diabetes are more likely to have poor physical (PH) and mental health (MH); however, there is limited research determining the relationship between MH and PH and routine check-up in diabetic middle-aged adults, especially by gender. The purpose of this study was to determine whether PH and MH status differ by routine check-up in middle-aged (age 45–64) adults with diabetes in the general population. Methods. This cross-sectional analysis used data from the 2017 BRFSS conducted by the CDC for adults aged 45–64 who reported having diabetes in Florida ( ), Kentucky ( ), Maryland ( ), New York ( ), and Ohio ( ). Multiple logistic regression by state and gender was used to determine the relationship between MH and PH status and routine check-up while controlling for health-related, socioeconomic, and demographic factors. Results. Across states, up to one-half reported good PH (32–50%), over one-half reported good MH (46–67%), and most reported having a routine check-up (87–93%). Adjusted analysis indicated that MH and PH were not significantly related to routine check-up, but both were inversely related to having diabetes plus two other health conditions. Conclusions. Overall, routine check-up was not related to good PH and MH in this target population; however, a number of health conditions were inversely related to good PH and MH status. In a primary care setting for this target population, there may be a low to moderate prevalence of good PH and MH and a high prevalence of having a routine check-up and having multiple health conditions. It is recommended to automatically screen this target population for PH, MH, other chronic conditions, and physical activity and treat concurrently.
In the Interior of Capital’s Exterminism: Burning up: a global history of fossil fuel consumption, by Simon Pirani, London, Pluto, 2018, 255 pp., $27.00/£17.09 (paperback), ISBN 10: 0745335616The birth of energy: fossil fuels, thermodynamics, and the politics of work, by Cara New Daggett, Durham, NC, Duke University Press, 2019, $26.95 (paperback), ISBN 10: 1478006323

To dig up the fossilized lifeforms of previous millennia, burn them for fuel to heat homes, propel cars, and send electricity through grids is not only a physical-technological act, but a political...
Computing as Curricular Peripheral

This paper builds on research done at our institution for an aspect of an REU summer program. Several Computer Science students tested avenues for varying complexities of game design and drew predictions and conclusions of their potential implementation into other academic disciplines. We look to Media Studies as one field with encouraging prospects for overlap, and discuss plans for a pilot course in Media Studies at a partnering institution for Spring 2020 which would make use of this possibility. Using this course as a model, we draw conclusions about the prospects, as well as possible limitations of computing as a peripheral to other academic fields, keeping in mind the importance of maintaining academic identity for all cooperating disciplines across the board.
Unusual cyanide and methyl binding modes at a dicobalt macrocycle following acetonitrile C–C bond activation

This communication describes the C–C bond activation of acetonitrile and the trapping of the methyl and cyanide fragments by macrocyclic, dicobalt complexes. Both products display unique structural features as a result of the constraints imposed by the macrocycle. The bridged species [(3PDI2)Co2(μ-CN)(PMe3)2][OTf] ([Co2CN]+) exhibits atypical Co–CN–Co binding, and upon either phosphine dissociation or oxidation, the flexible ligand framework is able to switch between different binding modes of μ-cyanide. Further, the bridging methyl species [(3PDI2)Co2(μ-CH3)(PMe3)][OTf] ([Co2CH3]+) is the first structurally characterized dicobalt complex with a bridging methyl group.
Parameter learning for latent network diffusion

Diffusion processes in networks are increasingly used to model dynamic phenomena such as the spread of information, wildlife, or social influence. Our work addresses the problem of learning the underlying parameters that govern such a diffusion process by observing the time at which nodes become active. A key advantage of our approach is that, unlike previous work, it can tolerate missing observations for some nodes in the diffusion process. Having incomplete observations is characteristic of offline networks used to model the spread of wildlife. We develop an EM algorithm to address parameter learning in such settings. Since both the E and M steps are computationally challenging, we employ a number of optimization methods such as nonlinear and difference-of-convex programming to address these challenges. Evaluation of the approach on the Red-cockaded Woodpecker conservation problem shows that it is highly robust and accurately learns parameters in various settings, even with more than 80% missing data.
Is Oxford Nanopore sequencing ready for analyzing complex microbiomes

This minireview will discuss the improvements in Oxford Nanopore (Oxford; sequencing technology that make the MinION a viable platform for microbial ecology studies. Specific issues being addressed are the increase in sequence accuracy from 65 to 96.5% during the last 5 years, the ability to obtain a quantifiable/predictive signal from the MinION with respect to target molecule abundance, simple-to-use GUI-based pathways for data analysis and the modest additional equipment needs for sequencing in the field. Coupling these recent improvements with the low capital costs for equipment and the reasonable per sample cost makes MinION sequencing an attractive option for virtually any laboratory.
Impacts of Tropical Cyclones on Longleaf Pine Ecosystems of Florida: Tropical Cyclogenesis, Landfall Frequencies, and Climate Change

Tropical storms and hurricanes (collectively hereafter, tropical cyclones) are among the most destructive forces in nature, with a total energy yield far exceeding that of volcanic eruptions and seismic activity. In addition to damaging winds, land-fall tropical cyclones generate excessive rain and storm surge, which commonly combine to create serious flooding. These threats are of particular concern to coastal areas of the southeastern United States, most especially in the State of Florida. This paper reviews environmental factors that lead to tropical cyclone formation, with a specific focus on (1) storm history and spatial distribution in Florida, and (2) the potential relationship between climate change and the frequency of tropical cyclones in the North Atlantic Ocean. Tropical cyclones are formed from a complex combination of meteorological conditions, driven primarily by the release of excess heat from the surface waters of the ocean, along with an unstable atmosphere comprising air temperatures decreasing and wind speeds increasing with altitude. Among the coastal counties (or parishes and boroughs, where appropriate) from Texas to Maine, Florida has experienced by far the highest frequency of tropical cyclones, especially the southern tip of peninsular Florida, with its most populous county (Miami-Dade) receiving 25 hits from 1900 to 2010, second only to Monroe County (32 hits) during that period. Frequencies of all categories of cyclones (tropical storms, hurricanes, major hurricanes) have exhibited statistically-significant increases from 1850 to the present. Cyclone frequencies were significantly correlated with increases in mean air and ocean temperatures, both of which have increased over the past, suggesting a causal relationship with anthropogenic climate change.
Acoustic Droplet Vaporization of Perfluorocarbon Droplets in 3D-Printable Gelatin Methacrylate Scaffolds

Scientists face a significant challenge in creating effective biomimetic constructs in tissue engineering with sustained and controlled delivery of growth factors. Recently, the addition of phase-shift droplets inside the scaffolds is being explored for temporal and spatial control of biologic delivery through vaporization using external ultrasound stimulation. Here, we explore acoustic droplet vaporization (ADV) in gelatin methacrylate (GelMA), a popular hydrogel used for tissue engineering applications because of its biocompatibility, tunable mechanical properties and rapid reproducibility. We embedded phase-shift perfluorocarbon droplets within the GelMA resin before crosslinking and characterized ADV and inertial cavitation (IC) thresholds of the embedded droplets. We were successful in vaporizing two different perfluorocarbon---perfluoropentane (PFP) and perfluorohexane (PFH)--cores at 2.25- and 5-MHz frequencies and inside hydrogels with varying mechanical properties. The ADV and IC thresholds for PFP droplets in GelMA scaffolds increased with frequency and in stiffer scaffolds. The PFH droplets exhibited ADV and IC activity only at 5 MHz for the range of excitations below 3MPa investigated here and at threshold values higher than those of PFP droplets. The results provide a proof of concept for the possible use of ADV in hydrogel scaffolds for tissue engineering.
A robust packet scheduling algorithm for proportional delay differentiation services

The proportional delay differentiation (PDD) model is an important approach for relative differentiated services provisioning on the Internet. It aims to maintain pre-specified packet queueing-delay ratios between different classes of traffic at each hop. Existing PDD packet scheduling algorithms are able to achieve the goal in long time-scales when the system is highly utilized. The paper presents a new PDD scheduling algorithm, called Little's average delay (LAD), based on a proof of Little's law. It monitors the arrival rate and the cumulative delays of the packets from each traffic class, and schedules the packets according to their transient queueing properties so as to achieve the desired class delay ratios in both short and long time-scales. Simulation results show that, in comparison with other PDD scheduling algorithms, LAD can provide no worse level of service quality in long time-scales and more accurate and robust control over the delay ratio in short time-scales. In particular, LAD outperforms its main competitors significantly when the desired delay ratio is large.
Reductio ad Hitlerum: Trumping the Judicial Nazi Card

Hitler was a vegetarian, as was Gandhi. Therefore, Gandhi, like Hitler, was evil. The absurdity of the above statement will be apparent to most readers. Indeed, the ability to understand why these premises do not lead to the conclusion following them is fundamental to being able to understand or perform legal analysis. Nonetheless, judicial opinions commonly include arguments that compare people and institutions with honorable intentions and authority derived from legitimate sources to Hitler, other Nazis or Nazism. For example, in considering whether a Miami police department acted lawfully when it randomly boarded buses and asked passengers for permission to search their bags for drugs, a state court judge reminded readers that Florida was not “Hitler’s Berlin, nor Stalin’s Moscow, [nor]...white supremacist South Africa.” Justice Thurgood Marshall found this language so convincing that he quoted it in a dissenting opinion when the Supreme Court subsequently addressed the legality of this police technique. Dozens of similar examples exist in American judicial opinions.This article has two goals. First, to analyze the reductio ad hitlerum fallacy, which is a pun of reductio ad absurdum coined by ethicist Leo Strauss for the fallacy that calls on the reader to condemn anything that has a common attribute to Hitler. Second, this article seeks to help readers develop a framework for using the tools of classical logic to analyze arguments and recognize fallacies (including reductio ad hitlerum) as a way to improve legal argumentation and critical thinking.
Trust Management in Distributed Databases

Businesses and the military must be able to incorporate information from a number of sources in different formats to remain competitive. As the need for information increases, more applications are utilizing distributed databases. Data is collected from multiple sources in multiple formats and is combined into data warehouses or datamarts. For example, military applications are incorporating distributed databases to combine sensor information for use in command and control. Intelligent agents can already search the web for information sources. However, issues of interconnectivity among the agents and information sources, data overflow, data validity, and security remain to be addressed. This article addresses the security and data validity issues. Specifically, the article addresses trust management and its application to obtaining information utilizing an inherently untrustworthy medium.
Morphology and Kinematics of the Molecular, Atomic, and Ionized Gas in the Inner Seven Parsecs of the Galaxy

The gas in the inner few parsecs of the Galaxy is of interest for two principal reasons: it is an important part of the contents of that region, which is closely related to the hypothesized feeding mechanism of active galactic nuclei, and it provides an important probe of the gravitational potential of the nuclear star cluster and possible black hole. Between about 1.5 and 7 pc, most of the gas is molecular, with much of it forming a rotating disk, with orbital speed ~ 110km s-1. Inside of 1.5 pc, the gas is partially ionized. The ionized component shows a complicated pattern of streamers, at least the two brightest of which he near the plane of the molecular disk. The velocities of the ionized gas rise from that of the molecular gas at 1.5 pc to > 300 km s-1 at 0.1 pc from the center. These observations give strong support for the existence of a central black hole of ~2 × 106 M⊙, embedded in a star cluster containing 2.5 – 3.0 × 106 M⊙ per parsec of radius.
Enzyme Complex Which Couples Glycerol-3-Phosphate Dehydrogenation to Fumarate Reduction in Escherichia coli

Abstract Anaerobic growth of Escherichia coli on glycerol as carbon source and fumarate as hydrogen acceptor results in the induction of both anaerobic sn-glycerol-3-phosphate (G3P) dehydrogenase and fumarate reductase. In previous studies, the G3P dehydrogenase was measured by the G3P-dependent reduction of a tetrazolium dye mediated by phenazine methosulfate in the presence of flavine mononucleotide and flavine adenine dinucleotide, and fumarate reductase was measured by the fumarate-dependent oxidation of reduced flavine mononucleotide. Results from the present study indicate that these two enzymes actually constitute a functional complex which is sedimentable at 200,000 × g in 2 h and which can catalyze the dehydrogenation of G3P at the expense of fumarate without any added cofactor. This coupling activity is not constituted by simply mixing an extract containing anaerobic G3P dehydrogenase with another extract containing fumarate reductase. Additional evidence for an organized complex is provided by the high degree of sensitivity of the coupled reaction to low concentrations of the detergents Triton X-100 and Emasol 1130 in comparison with the individual activities of the two component enzymes measured with the aid of artificial cofactors.
Computer based optimization techniques for the design of HDSL

The design and optimization of the high-speed digital subscriber line (HDSL) need powerful computational strategies. Traditional techniques of distributing poles and zeros on Smith charts generally do not work. In the past, such approaches have lead to suboptimal designs for applications where the data capacity sought is considerably less than the Shanon capacity of the lines. Typical subscriber loops are less than perfect and for the current demands on the HDSL at T1/T2 and E1 rates every possible venue for the HDSL design need to be investigated, if not exploited. The authors present flexible computational techniques that explore and optimize system components in view of operating environment of the HDSL and/or the asymmetric digital subscriber line (ADSL), and the inherent limitations of the system components. The optimization occurs automatically by forcing the computer to track the effects of incremental changes of the subsystem performance (e.g. echo cancelers or equalizers), or the component values (R's and C's in the matching circuits) in context of the functional constraints of the line (HDSL, ADSL, duplex, dual-duplex, triplex, etc.) in conjunction with the subscriber loop (CSA, Loops >
Beyond immediate hypersensitivity: evolving roles for IgE antibodies in immune homeostasis and allergic diseases.

Immunoglobulin E (IgE) antibodies have long been recognized as the antigen-specific triggers of allergic reactions. This review briefly introduces the established functions of IgE in immediate hypersensitivity and then focuses on emerging evidence from our own investigations as well as those of others that IgE plays important roles in protective immunity against parasites and exerts regulatory influences in the expression of its own receptors, FceRI and CD23, as well as controlling mast cell homeostasis. We provide an overview of the multifaceted ways in which IgE antibodies contribute to the pathology of food allergy and speculate regarding potential mechanisms of action of IgE blockade.
Thermodynamics of Three-Way Multibranch Loops in RNA†

RNA multibranch loops (junctions) are loops from which three or more helices exit. They are nearly ubiquitous in RNA secondary structures determined by comparative sequence analysis. In this study, systems in which two strands combine to form three-way junctions were used to measure the stabilities of RNA multibranch loops by UV optical melting and isothermal titration calorimetry (ITC). These data were used to calculate the free energy increment for initiation of a three-way junction on the basis of a nearest neighbor model for secondary structure stability. Imino proton NMR spectra were also measured for two systems and are consistent with the hypothesized helical structures. Incorporation of the experimental data into the mfold and RNA structure computer programs has contributed to an improvement in prediction of RNA secondary structure from sequence.
Emotional suppression mediates the relation between adverse life events and adolescent suicide: implications for prevention.

Suicidal ideation substantially increases the odds of future suicide attempts, and suicide is the second leading cause of death among adolescents. A history of adverse life events has been linked with future suicidal ideation and attempts, although studies examining potential mediating variables have been scarce. One probable mediating mechanism is how the individual copes with adverse life events. For example, certain coping strategies appear to be more problematic than others in increasing future psychopathology, and emotional suppression in particular has been associated with poor mental health outcomes in adults and children. However, no studies to date have examined the potential mediating role of emotional suppression in the relation between adverse life events and suicidal thoughts/behavior in adolescence. The goal of the current study was to examine emotional suppression as a mediator in the relation between childhood adversity and future suicidal thoughts/behaviors in youth. A total of 625 participants, aged 14–19 years, seeking ER services were administered measures assessing adverse life events, coping strategies, suicidal ideation in the last 2 weeks, and suicide attempts in the last month. The results suggest that emotional suppression mediates the relation between adversity and both (1) suicidal thoughts and (2) suicide attempts above and beyond demographic variables and depressive symptoms. This study has important implications for interventions aimed at preventing suicidal thoughts and behavior in adolescents with histories of adversity.
Incidence of deep vein thrombosis is increased with 30 mg twice daily dosing of enoxaparin compared with 40 mg daily.

Abstract Background The purpose of this study was to analyze whether 2 standard dosing regimens of enoxaparin (30 mg twice daily vs 40 mg once daily) would result in different deep vein thrombosis (DVT) rates and anti-factor Xa activity (anti-Xa) in surgical patients. Methods Patients who required enoxaparin for prophylaxis were followed prospectively. Demographics were recorded. Patients underwent standardized duplex screening. Peak anti-Xa levels were drawn on 4 consecutive days. Results Sixty-three patients were followed up (28 patients on 30 mg twice daily, 35 patients on 40 mg once daily). There was no significant difference in demographics between groups. Twenty-five percent of patients on 30 mg twice daily developed a DVT, whereas 2.9% of patients on 40 mg once daily developed a DVT. Patients on 30 mg twice daily had significantly lower anti-Xa levels. Conclusions The incidence of DVT is increased in surgical patients who receive 30 mg twice daily dosing of enoxaparin compared with 40 mg daily. Dosing of 40 mg once daily results in significantly higher peak anti-Xa levels compared with 30 mg twice daily.
Stem Cell Transplantation

Stem cell transplantation (SCT), also referred to as bone marrow transplantation or hematopoietic SCT, is a treatment in which hematopoietic stem cells are administered to a patient, usually as treatment for hematologic cancer or bone marrow failure. Prior to infusion of stem cells, patients receive fully myeloablative or reduced-intensity chemotherapy both to reduce tumor burden and to allow engraftment of the stem cells. There are several potential sources of the hematopoietic stem cells in clinical use. In autologous SCT, hematopoietic stem cells are collected from the patient prior to chemotherapy and infused after treatment to rescue the hematopoietic system. In allogeneic SCT, hematopoietic stem cells are donated by a close relative or genetically matched unrelated individual and infused after conditioning chemotherapy. Availability of suitably matched donors remains a major limitation to SCT and new advances now allow for more flexibility in matching human leukocyte antigens (HLA) between donors and recipients. Alternative stem cell sources include the use of partially matched relatives, partially matched unrelated donors, and umbilical cord fetal blood.
Splitting water with rust: hematite photoelectrochemistry

This article focuses on the promise, problems and progress of utilizing hematite for photocatalyzed water oxidation. Issues which require further research are also presented.
Absolute rate constants for the reaction of silyl with nitric oxide, ethylene, propyne, and propylene, and the silyl recombination reaction

Abstract The kinetics of the reactions SiH 3 + SiH 3 and SiH 3 + NO, SiH 3 + C 3 H 6 , C 3 H 4 , and C 2 H 4 are examined with time-resolved IR diode laser spectroscopy. The use of SiH 3 Br as a precursor for direct photochemical production of SiH 3 at 193 nm is demonstrated. SiH 3 is observed to react with NO ( k (NO) = (2.5 ± 0.5) × 10 −12 cm 3 molecule −1 s −1 ), C 3 H 6 and C 3 H 4 ( k (C 3 H 6 ) = (2.4 ± 0.3) × 10 −13 and k (C 3 H 4 ) ⩽ (1.8 ± 0.4) × 10 −14 cm 3 molecule −1 s −1 ) but is unreactive toward C 2 H 4 ( k (C 2 H 4 ) ⩽ (3 ± 3) × 10 −15 cm 3 molecule −1 s −1 ). An upper limit to the bimolecular rate constant for the radical recombination process, SiH 3 + SiH 3 , is determined, k rc ⩽ (6.1 ± 3.5) × 10 −11 cm 3 molecule −1 s −1 .
Edge-connectivity in regular multigraphs from eigenvalues

Abstract Let G be a d -regular multigraph, and let λ 2 ( G ) be the second largest eigenvalue of G . In this paper, we prove that if λ 2 ( G ) d − 1 + 9 d 2 − 10 d + 17 4 , then G is 2-edge-connected. Furthermore, for t ≥ 2 we show that G is ( t + 1 ) -edge-connected when λ 2 ( G ) d − t , and in fact when λ 2 ( G ) d − t + 1 if t is odd.
Effects of tenorraphy on the gliding function and tensile properties of partially lacerated canine digital flexor tendons.

Abstract Management of a partially lacerated digital flexor tendon within zone II remains controversial. To address this issue, we undertook an evaluation of the impact of tenorrhaphy on the gliding function and tensile properties of canine flexor tendons with lacerations involving either 30% or 70% of their cross-sectional area. Assessment of tendon excursion and joint rotation after 6 weeks of postoperative controlled passive mobilization failed to reveal any statistically significant benefit from tenorrhaphy on the gliding function. In fact, we demonstrated a significant negative effect of repair on tendons with 30% lacerations. Moreover, no significant differences between the structural properties or integrity of the repaired and nonrepaired tendons could be demonstrated. Thus, in light of the inherent tensile properties in these partially lacerated tendons, our data suggest that digital function of partially lacerated tendons of up to 70% of the cross-sectional area may be preserved without primary repair. However, additional work is needed to more definitively address this issue in a clinical context. (J Hand Surg 1999;24A:302–309. Copyright © 1999 by the American Society for Surgery of the Hand.)
Towards optimizing the reliability of real-time transmission in multi-hop wireless LANs

Three factors have been often shown to significantly affect the reliability of real-time transmission in wireless local area networks--transmission rate, power, and packet size. We analyze these factors and determine the optimal combination of factors subject to time constraints that yields the most reliable transmission of real-time data. We propose a cross-layer framework to jointly design the routing and MAC protocol combined with our optimization approach. The approach under a non-real-time routing protocol that produces a path metric is compared with a real-time routing protocol. Additionally, the real-time routing protocol enhances a guaranteed rate with our approach. Our experiments reveal that real-time performance in terms of miss ratio and throughput is significantly increased in lossy link and heavy traffic environments. Miss ratio and average throughput are improved by up to 25% over existing real-time routing protocols and 30% over a MAC protocol, respectively.
Modeling neutron guides using Monte Carlo simulations

Abstract Four neutron guide geometries, straight, converging, diverging and curved, were characterized using Monte Carlo ray-tracing simulations. The main areas of interest are the transmission of the guides at various neutron energies and the intrinsic time-of-flight (TOF) peak broadening. Use of a δ-function time pulse from a uniform Lambert neutron source allows one to quantitatively simulate the effect of guides’ geometry on the TOF peak broadening. With a converging guide, the intensity and the beam divergence increases while the TOF peak width decreases compared with that of a straight guide. By contrast, use of a diverging guide decreases the intensity and the beam divergence, and broadens the width (in TOF) of the transmitted neutron pulse.