cssi/SciSciGPT-SciSciNet huggingface dataset:
Show me the code: Spatial analysis and open source

This paper considers the intersection of academic spatial analysis with the open source revolution. Its basic premise is that the potential for cross-fertilization between the two is rich, yet some misperceptions about these two communities pose challenges to realizing these opportunities. The paper provides a primer on the open source movement for academicians with an eye towards correcting these misperceptions. It identifies a number of ways in which increased adoption of open source practices in spatial analysis can enhance the development of the next generation of tools and the wider practice of scientific research and education.
Omission of routine chest x-ray after chest tube removal is safe in selected trauma patients.

Abstract Background Definitive practice guidelines regarding the utility of chest x-ray (CXR) following chest tube removal in trauma patients have not been established. The authors hypothesized that the selective use of CXR following chest tube removal is safe and cost effective. Methods A retrospective review of chest tube insertions performed at a level I trauma center was conducted. Results Patients who underwent chest tube removal without subsequent CXR had a lower mean Injury Severity Score and were less likely to have suffered penetrating thoracic injuries. These patients received fewer total CXRs and had shorter durations of chest tube therapy and shorter lengths of stay following tube removal. Subsequent reinterventions were performed more frequently in the CXR group. The annual decrease in hospital charges by foregoing a CXR was $16,280. Conclusions The selective omission of CXR following chest tube removal in less severely injured, nonventilated patients does not adversely affect outcomes or increase reintervention rates. Avoiding unnecessary routine CXR after chest tube removal could provide a significant reduction in total hospital charges.
Zollinger-Ellison Syndrome with Subsequent Association of Insulinoma

A 64-year-old woman was admitted to our hospital in 2000 for evaluation of severe epigastric pain, chronic diarrhea and a 11.5 kg weight loss over last few years. Past medical and family history were unrevealing for any endocrine tumors. Esophagogastroduodenoscopy showed severe duodenitis and an atypical post-bulbar ulcer. Because of the classic presentation, atypical peptic ulcer disease and chronic diarrhea with weight loss, we pursued a work-up for Zollinger-Ellison syndrome. Her serum gastrin level was elevated (198 pg/mL; reference range: 0-42 pg/mL). CT scan of the abdomen and endoscopic retrograde cholangiopancreatography showed a 3 cm mass in the head of the pancreas compressing the main pancreatic duct. Subsequent octreotide scan revealed an octreotide positive mass in head of the pancreas suggestive of a neuroendocrine tumor. Serum insulin, glucagon, somatostatin and vasointestinal polypeptide (VIP) levels were within normal range. She underwent a Whipple procedure in 2000 with resection of the mass that proved to be a 2.8 cm gastrinoma with focal venous and perineural invasion (Figure 1). All resected lymph nodes were negative on HE ALT 135 U/L, reference range: 7-49 U/L; alkaline phosphatase 671 U/L, reference range: 32-104 U/L). CT scan of the abdomen demonstrated a new area of low attenuation in the right lobe of the liver
A statistical approach to set classification by feature selection with applications to classification of histopathology images.

Summary Set classification problems arise when classification tasks are based on sets of observations as opposed to individual observations. In set classification, a classification rule is trained with N sets of observations, where each set is labeled with class information, and the prediction of a class label is performed also with a set of observations. Data sets for set classification appear, for example, in diagnostics of disease based on multiple cell nucleus images from a single tissue. Relevant statistical models for set classification are introduced, which motivate a set classification framework based on context-free feature extraction. By understanding a set of observations as an empirical distribution, we employ a data-driven method to choose those features which contain information on location and major variation. In particular, the method of principal component analysis is used to extract the features of major variation. Multidimensional scaling is used to represent features as vector-valued points on which conventional classifiers can be applied. The proposed set classification approaches achieve better classification results than competing methods in a number of simulated data examples. The benefits of our method are demonstrated in an analysis of histopathology images of cell nuclei related to liver cancer.
SYNTHESIS AND APPLICATIONS OF SUPRAMOLECULAR-TEMPLATED MESOPOROUS MATERIALS

The unique structure of MCM-41 silicates (shown in the picture) has provided for extremely attractive properties—uniform pore sizes greater than 20 A, surface areas exceeding 1000 m2 g−1, and long-range ordering of the pores. Recent research in supramolecular-templated mesoporous materials has led to a wide range of compositions, to uses in a variety of catalytic reactions, and to a better control of bulk morphologies.
A Service-Oriented Approach to Security--Concepts and Issues

Various mechanisms for authentication and access control have been developed over time. Operating systems and DBMS implement such mechanisms and support quite rich access control models. A major limitation, however, of such mechanisms is that they are not extensible; thus whenever an application domain requires more sophisticated access controls or authentication, the applications must include logics for such controls. Such an approach leads to increased costs in application development and maintenance. For these reasons, models and mechanisms apt to separate those functions have emerged, also fostered by XML and Web services.-At the same time, the need to drive the behaviour of security through clearly stated and machine-processable policies has fostered the development of various policy models and policy management mechanisms. A policy-based approach enhances flexibility, and reduces the application development costs. Changes to the access control or authentication requirements simply entail modifying the policies, without requiring changes to the applications. It is thus clear that an important approach to the problem of security is represented by the development of policy-based security services providing all functions for security management relevant to applications. Such an approach is particularly promising for applications organized according to the Service Oriented (SOA) paradigm. In this paper we discuss basic concepts of such an approach to security and we present a reference architectural framework. We discuss three relevant classes of security services, namely digital identity management services, authentication services, access control services, and outline research directions for each such class
On the intersection theory of the moduli space of rank two bundles

We give an algebro-geometric derivation of the known intersection theory on the moduli space of stable rank 2 bundles of odd degree over a smooth curve of genus g. We lift the computation from the moduli space to a Quot scheme, where we obtain the intersections via equivariant localization with respect to a natural torus action.
The impact of NRZ data asymmetry on the performance of a space telemetry system

The author derives an expression for the power spectral density of an asymmetric nonreturn-to-zero (NRZ) data stream. This formula is used to investigate how the data bandwidth varies with data asymmetry. The threshold levels of undesired spectral components that fall into the carrier tracking loop bandwidth are determined by examining the derived spectral density. Based on this formula, a simple technique is developed for the computation of bit signal-to-noise ratio (SNR) degradation due to data asymmetry. The telemetry bit SNR degradations derived using this technique are compared with the results obtained previously by M.K. Simon et al. (1978) and with measurements by the electronic systems test laboratory (ESTL) at the Lyndon B. Johnson Space Center. >
A decomposition approach to flow control in tandem production systems

Proposes a decomposition method to production rate control for a tandem production system in which machines are subject to failures and repairs. The basic idea of the author's method is to decompose the system into single-machine systems. The interaction between the machines is characterized by shortage/starvation costs.
Coupling pulsed dye oscillators using a phase conjugate resonator.

Four pulsed dye oscillators are coherently combined into a single phase conjugate resonator through the self-pumped conjugation process in a single crystal of BaTiO3. We have measured the locking range and energy scaling behavior of the system. The locking range is of the order of hundreds of wavelengths. Our best results are close to the theoretical limit and show that one can obtain output energy approximately proportional to N, the number of dye gain cells. Since the N output beams are locked in phase, this implies that the peak far-field intensity would scale as N2. We also report two properties of the photorefractive phase conjugate mirror that are relevant to such a system: the fluence required for start-up (9 J/cm2) and the field of view (0.1 sr).
Global well-posedness of the Benjamin–Ono equation in low-regularity spaces

We prove that the Benjamin-Ono initial value problem is globally well-posed in the Sobolev spaces $H^\sigma_r$, $\sigma\geq 0$.
Nonlinear Outcome of Gravitational Instability in Cooling, Gaseous Disks

Thin, Keplerian accretion disks generically become gravitationally unstable at large radii. I investigate the nonlinear outcome of such instability in cool disks using razor-thin, local, numerical models. Cooling, characterized by a constant cooling time τc, drives the instability. I show analytically that if the disk can reach a steady state in which heating by dissipation of turbulence balances cooling, then the dimensionless angular momentum flux density α = -1. Numerical experiments show that (1) if τc 3Ω-1 then the disk reaches a steady, gravitoturbulent state in which Q ~ 1 and cooling is balanced by heating due to dissipation of turbulence; (2) if τc 3Ω-1, then the disk fragments, possibly forming planets or stars; (3) in a steady, gravitoturbulent state, surface density structures have a characteristic physical scale ~64GΣ/Ω2 that is independent of the size of the computational domain.
Tumor Necrosis Factor-α–Converting Enzyme (ADAM17) Mediates GPIbα Shedding From Platelets In Vitro and In Vivo

Interaction of the platelet receptor glycoprotein (GP) Ib-V-IX with von Willebrand factor exposed at a site of vascular injury is an essential step in the initiation of a hemostatic plug. Proteolytic cleavage (shedding) of the GPIbα subunit was first described >25 years ago, the protease mediating this event as well as its physiological function, however, have not been elucidated. We reported recently that shedding of GPIbα induced by platelet storage or mitochondrial injury involves a platelet-derived metalloproteinase(s). Here we show that GPIbα shedding in response to mitochondrial injury or physiological activation is inhibited in platelets obtained from chimeric mice, which express inactive tumor necrosis factor-α converting enzyme (TACEΔZn/ΔZn) in blood cells only. Shedding was also inhibited in mouse and human platelets in the presence of 2 potent TACE inhibitors: TAP1 and TMI-1. Our data further suggest that TACE is important in the regulation of GPIbα expression in vivo because we observed an ≈90...
Biological activities of pyridoacridines.

Covering: 1983–2003This review consolidates biological activity data reported for pyridoacridine 1 molecules in the literature from 1983–2003 into several tables with brief discussions of assays used and results obtained. This review summarizes recent progress in structure activity relationships for analogues of amphimedine 2 and ascididemin 3 classes of pyridoacridines and correlates reported molecular mechanisms of action with biological activities.
Synthesis and photocleavage of a new dimeric bis(o-nitrobenzyl) diether tether

A new photocleavable linker, 4,4′-bis(alkoxymethyl-3,3′-dinitro)biphenyl, is reported that undergoes photolysis at two positions to release two equivalents of primary, secondary, or benzylic alcohol in yields that are higher than those obtained from the analogous monomeric o-nitrobenzyl ethers.
Kinetics of Titanium(IV) Chloride Oxidation

The oxidation rate of TiCl4 vapor was measured by FTIR spectroscopy between 700° and 1000°C in a furnace aerosol reactor. The reaction rate was found to be first order with respect to TiCl4 and to follow the Arrhenius form. The apparent activation energy for the reaction was 88.8 ± 3.2 kJ/mol and the preexponential factor 8.26 × 104 s−1. A kinetic mechanism for the oxidation of TiCl4 was proposed that was consistent with the observed dependence of oxygen concentration on the apparent rate constant.
Delay of transfer from the intensive care unit: a prospective observational study of incidence, causes, and financial impact

Introduction: A paucity of literature exists regarding delays in transfer out of the intensive care unit. We sought to analyze the incidence, causes, and costs of delayed transfer from a surgical intensive care unit (SICU). Methods: An IRB-approved prospective observational study was conducted from January 24, 2010, to July 31, 2010, of all 731 patients transferred from a 20-bed SICU at a large tertiary-care academic medical center. Data were collected on patients who were medically ready for transfer to the floor who remained in the SICU for at least 1 extra day. Reasons for delay were examined, and extra costs associated were estimated. Results: Transfer to the floor was delayed in 22% (n = 160) of the 731 patients transferred from the SICU. Delays ranged from 1 to 6 days (mean, 1.5 days; median, 2 days). The extra costs associated with delays were estimated to be $581,790 during the study period, or $21,547 per week. The most common reasons for delay in transfer were lack of available surgical-floor bed (71% (114 of 160)), lack of room appropriate for infectious contact precautions (18% (28 of 160)), change of primary service (Surgery to Medicine) (7% (11 of 160)), and lack of available patient attendant ("sitter” for mildly delirious patients) (3% (five of 160)). A positive association was found between the daily hospital census and the daily number of SICU beds occupied by patients delayed in transfer (Spearman rho = 0.27; P < 0.0001). Conclusions: Delay in transfer from the SICU is common and costly. The most common reason for delay is insufficient availability of surgical-floor beds. Delay in transfer is associated with high hospital census. Further study of this problem is necessary.
Iterative receivers for space-time block-coded OFDM systems in dispersive fading channels

We consider the design of iterative receivers for space-time block-coded orthogonal frequency-division multiplexing (STBC-OFDM) systems in unknown wireless dispersive fading channels, with or without outer channel coding. First, we propose a maximum-likelihood (ML) receiver for STBC-OFDM systems based on the expectation-maximization (EM) algorithm. By assuming that the fading processes remain constant over the duration of one STBC code word and by exploiting the orthogonality property of the STBC as well as the OFDM modulation, we show that the EM-based receiver has a very low computational complexity and that the initialization of the EM receiver is based on the linear minimum mean square error (MMSE) channel estimate for both the pilot and the data transmission. Since the actual fading processes may vary within one STBC code word, we also analyze the effect of a modeling mismatch on the receiver performance and show both analytically and through simulations that the performance degradation due to such a mismatch is negligible for practical Doppler frequencies. We further propose a turbo receiver based on the maximum a posteriori-EM algorithm for STBC-OFDM systems with outer channel coding. Compared with the previous noniterative receiver employing a decision-directed linear channel estimator, the iterative receivers proposed here significantly improve the receiver performance and can approach the ML performance in typical wireless channels with very fast fading, at a reasonable computational complexity well suited for real-time implementations.
News on the Internet

Newspapers are in trouble. Circulation and advertising are down as readers shift from print to online media. Although changing reader preferences and the loss of lucrative classified advertising to online sources are major worries, the news media seems preoccupied with news aggregators and bloggers who distribute news content on the internet without permission. Newspapers are not the only ones worried about the unauthorized distribution of “their” news on the internet. Financial services companies are unhappy about the distribution of their ”hot” stock recommendations and other content providers seek to control online news ranging from movie schedules to business ratings. Traditional copyright doctrine offers varying degrees of protection for the literary format of the news — broad in scope for the text of news stories, narrower and less certain for smaller expressions like news headlines and leads. Content providers want more. They seek to control the online distribution not just of their literary forms, but of the very facts that are the news itself. The battle is being waged on two fronts. One involves an attempt to extend the traditional scope of copyright beyond the protection of expression into the previously forbidden realm of facts. The second front involves efforts by content providers to enlist the century-old common law tort of misappropriation. The reemergence of the misappropriation tort from the shadow of federal copyright law is somewhat improbable, resting as it does on a single paragraph of legislative history, extracted from an ABA Committee Report, that was directed at a portion of the copyright revision bill that was never actually enacted. Nevertheless, its application to news on the internet has been cheered by many commentators. This Article examines the recent attempts by content providers to gain control over facts through federal copyright law and the common law tort of
Numerical Analysis of Flowfields Generated by Accelerating Flames

A numerical technique is presented for the analysis of nonsteady flowfields generated by accelerating flames in gaseous media. The problem is formulated in Eulerian coordinates and the solution is based on the extension of the floating shock-fitting technique to all the discontinuities and their interactions occurring in the flowfield. Besides shock waves, the discontinuities taken into account thus far consist of contact surfaces, deflagration, and detonation fronts. The governing partial differential equations are integrated by the use of an explicit second-order accurate, finite-difference scheme, while special algorithms are introduced for the treatment of segments of the flowfield where the influence zones of discontinuities overlap. Actual interactions between them are treated by the polar intersection method. The technique is applied to the case of a steady flame experiencing an abrupt increase in burning speed, leading either to the establishment of a new steady flame flow system or to further acceleration culminated by the transition to detonation. A demarcation line between the two regimes of solutions, depending on the value of the initial burning speed and the magnitude of its abrupt increase, is established, and the physical validity of this criterion is corroborated by experimental evidence.
Discrepancy Convergence for the Drunkard's Walk on the Sphere

We analyze the drunkard's walk on the unit sphere with step size $\theta$ and show that the walk converges in order $C/\sin^2(\theta)$ steps in the discrepancy metric ($C$ a constant). This is an application of techniques we develop for bounding the discrepancy of random walks on Gelfand pairs generated by bi-invariant measures. In such cases, Fourier analysis on the acting group admits tractable computations involving spherical functions. We advocate the use of discrepancy as a metric on probabilities for state spaces with isometric group actions.
Sudden acceleration of a laminar boundary layer by a moving belt

Abstract : The paper suggested a method for analysis of boundary layers encountering a sudden change in boundary conditions based on a transformation into a new coordinate system which, though not appropriate for the original boundary layer, is nevertheless essential to the description of the perturbation caused by the new boundary conditions. Specifically, an incompressible, laminar boundary layer of the Falkner-Skan type is assumed to be suddenly accelerated by a belt moving in the plane of the wall at a constant speed in the downstream direction. General equations for such a flow are solved far away from, as well as close to, the location at which the boundary layer first encounters the moving belt. The results have shown that not only can the separation of the boundary layer be thus shifted infinitely far downstream, but also that a sufficiently rapid movement of the belt can produce in short distance a substantial acceleration of the flow leading to over-all frictional thrust instead of drag. As one may have intuitively expected, this last effect becomes greater the larger the belt velocity and the smaller the momentum loss of the original layer. (Author)
The effect of expiration dates and perceived risk on purchasing behavior in grocery store perishable categories

Abstract In this article, the authors examine consumers' behavior with respect to expiration dates for grocery store perishable products. A better understanding of such behavior can both guide efforts to educate consumers about the risks associated with perishables that are approaching their expiration dates and help managers implement effective promotional strategies for these products throughout the course of their shelf lives. Both of these approaches can help reduce waste due to spoilage.
Simultaneous Topology Optimization of Membrane Wings and Their Compliant Flapping Mechanisms

This work explores the interdependencies between the topological design of a compliant flapping mechanism and that of a flight-loaded elastic membrane-wing skeleton. This is done via a monolithic aeroelastic framework that encompasses the compliant-mechanism deformation, the motion of a flexible wing, and the transmission of aerodynamic and inertial forces back into the mechanism. A cellular-based evolutionary topology optimization scheme is used for mechanism design, wing design, or both simultaneously. The latter approach is shown to provide superior performance as this allows the tightly coupled nature of the two structures to be fully exploited. The results presented here also demonstrate potential issues that arise during wing design if the flapping kinematics are assumed to be prescribed. Finally, the mechanism topology is further improved via a gradient-based sizing/shape optimization to decrease actuator requirements as well as the time-dependent elastic stresses.
A period-processor-time-minimal schedule for cubical mesh algorithms

Using a directed acyclic graph (dag) model of algorithms, we investigate precedence-constrained multiprocessor schedules for the n/spl times/n/spl times/n directed mesh. This cubical mesh is fundamental, representing the standard algorithm for square matrix product, as well as many other algorithms. Its completion requires at least 3/sup n/spl minus/2/ multiprocessor steps. Time-minimal multiprocessor schedules that use as few processors as possible are called processor-time-minimal. For the cubical mesh, such a schedule requires at least /spl lsqb/3n/sup 2//4/spl rsqb/ processors. Among such schedules, one with the minimum period (i.e., maximum throughput) is referred to as a period-processor-time-minimal schedule. The period of any processor-time-minimal schedule for the cubical mesh is at least 3/sup n/2/ steps. This lower bound is shown to be exact by constructing, for n a multiple of 6, a period-processor-time-minimal multiprocessor schedule that can be realized on a systolic array whose topology is a toroidally connected n/2/spl times/n/2/spl times/3 mesh. >
Autonomous Helicopter Tracking and Localization Using a Self-surveying Camera Array

A Self-surveying Camera Array (SSCA) is a vision-based local-area positioning system consisting of multiple ground-deployed cameras that are capable of self-surveying their extrinsic parameters while tracking and localizing a moving target. This paper presents the self-surveying algorithm being used to track a target helicopter in each camera frame and to localize the helicopter in an array-fixed frame. Three cameras are deployed independently in an arbitrary arrangement that allows each camera to view the helicopter's flight volume. The helicopter then flies an unplanned path that allows the cameras to calibrate the relative locations and orientations by utilizing a self-surveying algorithm that is extended from the well-known structure from motion algorithm and the bundle adjustment technique. This yields the cameras'extrinsic parameters enabling real-time helicopter positioning via triangulation. This paper also presents results from field trials, which verify the feasibility of the SSCA as a readily-deployable system applicable to helicopter tracking and localization. The results demonstrate that, compared to the differential GPS solution as true reference, the SSCA alone is capable of positioning the helicopter with meter-level accuracy. The SSCA has been integrated with onboard inertial sensors providing a reliable positioning system to enable successful autonomous hovering.
Test generation of C-testable array dividers

The design of C-testable array dividers that are tested with a test set of constant length irrespective of the circuit size is presented. The results show that the proposed designs of n-by-n nonrestoring and restoring array dividers are C-testable and can be fully tested using only 20 and 40 test patterns, respectively. Algorithms that generate the test patterns and expected outputs are also provided. >
Response of the Midlatitude Jets, and of Their Variability, to Increased Greenhouse Gases in the CMIP5 Models

This work documents how the midlatitude, eddy-driven jets respond to climate change using model output from phase 5 of the Coupled Model Intercomparison Project (CMIP5). The authors consider separately the North Atlantic, the North Pacific, and the Southern Hemisphere jets. The analysis is not limited to annualmean changes in the latitude and speed of the jets, but also explores how the variability of each jet changes with increased greenhouse gases. All jetsarefoundto migratepolewardwith climatechange:theSouthernHemispherejetshiftspolewardby 28 of latitude between the historical period and the end of the twenty-first century in the representative concentration pathway 8.5 (RCP8.5) scenario, whereas both Northern Hemisphere jets shift by only 18 .I n addition, the speed of the Southern Hemisphere jet is found to increase markedly (by 1.2ms 21 between 850 and 700hPa), while the speed remains nearly constant for both jets in the Northern Hemisphere. More importantly, it is found that the patterns of jet variability are a strong function of the jet position in all three sectors of the globe, and as the jets shift poleward the patterns of variability change. Specifically, for the Southern Hemisphere and the North Atlantic jets, the variability becomes less of a north‐south wobbling and more of a pulsing (i.e.,variationin jet speed).In contrast,for the North Pacificjet, the variabilitybecomesless of a pulsing and more of a north‐south wobbling. These different responses can be understood in terms of Rossby wave breaking, allowing the authors to explain most of the projected jet changes within a single dynamical framework.
Signal transduction and control of lacrimal gland protein secretion: a review.

Proteins in lacrimal gland fluid are secreted primarily by the acinar cells. Secretory proteins are synthesized in the endoplasmic reticulum, modified in the Golgi apparatus, stored in secretory granules, and released upon a change in the cellular level of second messenger. The second messenger level is controlled by a process termed signal transduction. Agonists, primarily neu-rotransmitters in the lacrimal gland, bind to receptors in the basolateral membrane of Secretory cells. This interaction activates enzymes in the membrane that cause production of second messengers. It has been hypothesized that second messengers stimulate secretion by activating specific protein kinases to phosphorylate proteins important for secretion. In the lacrimal gland, cholinergic agonists stimulate protein secretion. They act by activating phospholipase C to break down phosphatidylinositol bisphosphate into 1,4,5-inositol trisphosphate (1,4,5-IP3) and diacylglycerol (DAG). 1,4,5-IP3 causes release of Ca2+ from intracellula...
Ablation of XP-V gene causes adipose tissue senescence and metabolic abnormalities

Obesity and the metabolic syndrome have evolved to be major health issues throughout the world. Whether loss of genome integrity contributes to this epidemic is an open question. DNA polymerase η (pol η), encoded by the xeroderma pigmentosum (XP-V) gene, plays an essential role in preventing cutaneous cancer caused by UV radiation-induced DNA damage. Herein, we demonstrate that pol η deficiency in mice (pol η−/−) causes obesity with visceral fat accumulation, hepatic steatosis, hyperleptinemia, hyperinsulinemia, and glucose intolerance. In comparison to WT mice, adipose tissue from pol η−/− mice exhibits increased DNA damage and a greater DNA damage response, indicated by up-regulation and/or phosphorylation of ataxia telangiectasia mutated (ATM), phosphorylated H2AX (γH2AX), and poly[ADP-ribose] polymerase 1 (PARP-1). Concomitantly, increased cellular senescence in the adipose tissue from pol η−/− mice was observed and measured by up-regulation of senescence markers, including p53, p16Ink4a, p21, senescence-associated (SA) β-gal activity, and SA secretion of proinflammatory cytokines interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) as early as 4 wk of age. Treatment of pol η−/− mice with a p53 inhibitor, pifithrin-α, reduced adipocyte senescence and attenuated the metabolic abnormalities. Furthermore, elevation of adipocyte DNA damage with a high-fat diet or sodium arsenite exacerbated adipocyte senescence and metabolic abnormalities in pol η−/− mice. In contrast, reduction of adipose DNA damage with N-acetylcysteine or metformin ameliorated cellular senescence and metabolic abnormalities. These studies indicate that elevated DNA damage is a root cause of adipocyte senescence, which plays a determining role in the development of obesity and insulin resistance.
Were the Good Old Days That Good? Changes in Managerial Stock Ownership Since the Great Depression

We document that ownership by officers and directors of publicly traded firms is on average higher today than earlier in the century. Managerial ownership has risen from 13 percent for the universe of exchange-listed corporations in 1935, the earliest year for which such data exist, to 21 percent in 1995. We examine in detail the robustness of the increase and explore hypotheses to explain it. Higher managerial ownership has not substituted for alternative corporate governance mechanisms. Lower volatility and greater hedging opportunities associated with the development of financial markets appear to be important factors explaining the increase in managerial ownership. THE SEPARATION OF OWNERSHIP AND CONTROL of firms has generated an enormous literature since the publication of Berle and Means' The Modern Corporation and Private Property (1932). In both academic and public policy circles, there has been much debate about the consequences of "absentee ownership" (Veblen (1923)) and what policies should be undertaken to remedy the situation. Berle and Means warn that the separation of ownership and control "destroys the very foundation on which the economic order of the past three centuries has rested" and assert that the "[d]ispersion in the ownership of separate enterprises . . . has already proceeded far, it is rapidly increasing, and appears to be an inevitable development" of the modern cor
Synthesis and spectral characterization of medium ring distannacycloalkanes and their Lewis acid derivatives

Abstract A study of the syntheses and some properties of several methyl substituted acyclic and cyclic bidentate organotin Lewis acids has been carried out. Of particular interest were cyclic species with 7-, 8-, 9- and 10-membered rings. The distannaalkanes and distannacycloalkanes were converted to the chlorides by chlorodemethylation with tin chlorides or mercuric chloride; this reaction was accompanied by ring cleavage in some cases. Chlorides, in turn, were readily converted to the methanesulfonates and trifluoromethanesulfonates. 1 H, 13 C and 119 Sn NMR and IR spectral data were used to gain information concerning structures, conformations and aggregation behavior. The mesylates are associated in chloroform; the triflates are not.
The LRPD test: speculative run-time parallelization of loops with privatization and reduction parallelization

Current parallelizing compilers cannot identify a significant fraction of parallelizable loops because they have complex or statically insufficiently defined access patterns. As parallelizable loops arise frequently in practice, we advocate a novel framework for their identification: speculatively execute the loop as a doall and apply a fully parallel data dependence test to determine if it had any cross-iteration dependences; if the test fails, then the loop is reexecuted serially. Since, from our experience, a significant amount of the available parallelism in Fortran programs can be exploited by loops transformed through privatization and reduction parallelization, our methods can speculatively apply these transformations and then check their validity at run-time. Another important contribution of this paper is a novel method for reduction recognition which goes beyond syntactic pattern matching: it detects at run-time if the values stored in an array participate in a reduction operation, even if they are transferred through private variables and/or are affected by statically unpredictable control flow. We present experimental results on loops from the PERFECT Benchmarks, which substantiate our claim that these techniques can yield significant speedups which are often superior to those obtainable by inspector/executor methods.
Optimal Material Logistics Planning in Congested Construction Sites

Scarcity of construction site space imposes serious challenges for contractors in planning material supply and site logistics. Existing models of material logistics and site layout planning face critical performance limitations in congested construction sites, due to their inability of modeling and utilizing interior building spaces for long-term material storage. This paper presents the development of a new Congested Construction Logistics Planning (C2LP) system that facilitates the optimal utilization of interior building spaces by considering shifting some of the non-critical activities in order to generate sufficient interior space for material storage areas. Accordingly, the model is designed to optimize two main conflicting objectives; minimizing site logistics costs and minimizing project criticality. Site logistics cost include material ordering, stock-out, carrying, and layout costs. These two objectives are optimized considering four main categories of decision variables: material supply, interior storage plan, exterior layout, and shifting of non-critical activities. The model is designed to incorporate a group of critical constraints, such as exterior layout and activities-materials spatiotemporal constraints. The performance and capabilities of the proposed model are evaluated using an application example of the construction of a multi-storey building in a congested site.
Three-dimensional range data interpolation using B-spline surface fitting

Many optical range sensors use an Equal Angle Increment (EAI) sampling. This type of sensors uses rotating mirrors with a constant angular velocity using radar and triangulation techniques, where the sensor sends and receives the modulated coherent light through the mirror. Such an EAI model generates data for surface geometrical description that has to be converted, in many applications, into data which meet the desired Equal Distance Increment orthographic projection model. For an accurate analysis in 3D images, a 3D interpolation scheme is needed to resample the range data into spatially equally-distance sampling data that emulate the Cartesian orthographic projection model. In this paper, a resampling approach using a B-Spline surface fitting is proposed. The first step is to select a new scale for all X, Y, Z directions based on the 3D Cartesian coordinates of range data obtained from the sensor parameters. The size of the new range image and the new coordinates of each point are then computed according to the actual references of (X, Y, Z) coordinates and the new scale. The new range data are interpolated using a B-Spline surface fitting based on the new Cartesian coordinates. The experiments show that this 3D interpolation approach provides a geometrically accurate solution for many industrial applications which deploy the EAI sampling sensors.
Dark matter from dynamical SUSY breaking

We consider explicit models of dynamical supersymmetry breaking where dark matter is a 10–100 TeV strongly-interacting composite state carrying no standard model quantum numbers. These constructions are simple variants of well-known supersymmetry breaking mechanisms, augmented to allow for a large “flavor” symmetry. Dark matter is the lightest composite modulus charged under this symmetry and is a viable cold dark matter candidate with a thermal relic abundance. This is an attractive possibility in low-scale gauge-mediated scenarios where the gravitino is the lightest superparticle. A light R-axion associated with supersymmetry breaking is present in these hidden sectors and serves as the portal between dark matter and the standard model. Such scenarios are relevant for present and future indirect detection experiments.
Why is the Japanese Conviction Rate So High

Abstract Conviction rates in Japan exceed 99 percent. Because Japanese judges can be penalized by a personnel office if they rule in ways the office dislikes, perhaps they face biased incentives to...
Constraints on Titan's topography through fractal analysis of shorelines

Titan’s north polar hydrocarbon lakes offer a unique opportunity to indirectly characterize the statistical properties of Titan’s landscape. The complexity of a shoreline can be related to the complexity of the landscape it is embedded in through fractal theory. We mapped the shorelines of 290 of the north polar titanian lakes in the Cassini synthetic aperture radar dataset. Out of these, we used a subset of 190 lake shorelines for our analysis. The fractal dimensions of the shorelines were calculated via two methods: the divider/ruler method and the box-counting method, at length scales of (1–10) km and found to average 1.27 and 1.32, respectively. The inferred power-spectral exponent of Titan’s topography (β) from theoretical and empirical relations is found to be ⩽2, which is lower than the values obtained from the global topography of the Earth or Venus. Some of the shorelines exhibit multi-fractal behavior (different fractal dimensions at different scales), which we interpret to signify a transition from one set of dominant surface processes to another. We did not observe any spatial variation in the fractal dimension with latitude; however we do report significant spatial variation of the fractal dimension with longitude. A systematic difference between the dimensions of orthogonal sections of lake shorelines is also noted, which signifies possible anisotropy in Titan’s topography. The topographic information thus gleaned can be used to constrain landscape evolution modeling to infer the dominant surface processes that sculpt the landscape of Titan.
Heterogeneous Gain Learning and the Dynamics of Asset Prices

This paper presents a new agent-based financial market. It is designed to be both simple enough to gain insights into the nature and structure of what is going on at both the agent and macro levels, but remain rich enough to allow for many interesting evolutionary experiments. The model is driven by heterogeneous agents who put varying weights on past information as they design portfolio strategies. It faithfully generates many of the common stylized features of asset markets. It also yields some insights into the dynamics of agent strategies and how they lead to market instabilities.
Conversion of D-mannose into 1,5-anhydro-D-allitol-4,6-acetonide; unusual intramolecular epoxy alcohol opening in base

reatment of 3-tosyl-D-mannose-4,6-acetonide 9 with sodium borohydride affords an epoxy alcohol 11 which on treatment with base gives 1,5-anhydro-D-allitol-4,6-acetonide 15 by a 6-endo opening of the rearranged epoxy alcohol 13 rather than the product of a 5-exo opening, namely a C-ribose acetonide derivative 14.
Overview of the ags cold snake power supplies and the new RHIC sextupole power supplies

The two rings in the Relativistic Heavy Ion Collider (RHIC) were originally constructed with 24 sextupole power supplies, 12 for each ring. Before the start of run 7, 24 new sextupole power supplies were installed, 12 for each ring. Individual sextupole power supplies are now each connected to six sextupole magnets. A superconducting snake magnet and power supplies were installed in the Alternating Gradient Synchrotron (AGS) and commissioned during RHIC run 5, and used operationally in RHIC run 6. The power supply technology, connections, control systems and interfacing with the quench protection system for both these systems will be presented.
Does the Milky Way Produce a Nuclear Galactic Wind

We detect high-velocity absorbing gas using Hubble Space Telescope and Far Ultraviolet Spectroscopic Explorer medium-resolution spectroscopy along two high-latitude active galactic nucleus (AGN) sight lines (Mrk 1383 and PKS2005� 489)aboveandbelowtheGalacticcenter(GC).Theseabsorptionsaremoststraightforwardlyinterpreted as a wind emanating from the GC that does not escape from the Galaxy’s gravitational potential. Spectra of four comparisonBstarsareusedtoidentifyandremoveforegroundvelocitycomponentsfromtheabsorption-lineprofiles of O vi ,N v ,C ii ,C iii ,C iv ,S iii ,S iiii, and Si iv. Two high-velocity (HV) absorption components are detected along each AGN sight line, three redshifted and one blueshifted. Assuming that the four HV features trace a large-scale Galactic wind emanating from the GC, the blueshifted absorber is falling toward the GC at a velocity of 250 � 20 km s � 1 , which can be explained by ‘‘Galactic fountain’’ material that originated in a bound Galactic wind. The otherthreeabsorbersrepresentoutflowingmaterial;thelargestderivedoutflowvelocityis+250 � 20 km s � 1 ,which is only 45% of the velocity necessary for the absorber to escape from its current position in the Galactic gravitational potential. All four HV absorbers are found to reach the same maximum height above the Galactic plane ( zmax jj ¼ 12 � 1 kpc), implying that they were all ejected from the GC with the same initial velocity. The derived metallicity limits of k10%–20% solar are lower than expected for material recently ejected from the GC unless these absorbers also contain significant amounts of hotter gas in unseen ionization stages.
Total Synthesis of Amaryllidaceae Alkaloids Utilizing Sequential Intramolecular Heterocyclic Azadiene Diels−Alder Reactions of an Unsymmetrical 1,2,4,5-Tetrazine

Convergent total syntheses of anhydrolycorinone, hippadine, and anhydrolycorinium chloride are detailed, enlisting sequential inverse electron demand Diels−Alder reactions of an unsymmetrical N-acyl-6-amino-1,2,4,5-tetrazine.
Asynchronous Computing in Sense Amplifier-Based Pass Transistor Logic

This paper presents the design and implementation of a low-energy asynchronous logic topology using sense amplifier-based pass transistor logic (SAPTL). The SAPTL structure can realize very low energy computation by using low-leakage pass transistor networks at low supply voltages. The introduction of asynchronous operation in SAPTL further improves energy-delay performance without a significant increase in hardware complexity. We show two different self-timed approaches: 1) the bundled data and 2) the dual-rail handshaking protocol. The proposed self-timed SAPTL architectures provide robust and efficient asynchronous computation using a glitch-free protocol to avoid possible dynamic timing hazards. Simulation and measurement results show that the self-timed SAPTL with dual-rail protocol exhibits energy-delay characteristics better than synchronous and bundled data self-timed approaches in 90-nm CMOS.
Distilled Sensing: Adaptive Sampling for Sparse Detection and Estimation

Adaptive sampling results in significant improvements in the recovery of sparse signals in white Gaussian noise. A sequential adaptive sampling-and-refinement procedure called Distilled Sensing (DS) is proposed and analyzed. DS is a form of multistage experimental design and testing. Because of the adaptive nature of the data collection, DS can detect and localize far weaker signals than possible from non-adaptive measurements. In particular, reliable detection and localization (support estimation) using non-adaptive samples is possible only if the signal amplitudes grow logarithmically with the problem dimension. Here it is shown that using adaptive sampling, reliable detection is possible provided the amplitude exceeds a constant, and localization is possible when the amplitude exceeds any arbitrarily slowly growing function of the dimension.
An Analysis of Online Examinations in College Courses

This research evaluates the use of online esa~ninaiions in college courses from both instructor and student perspectives. Instructional software was developed at Kansas State University to administer online homework assignments and examinations. Survey data were collected from two classes to measure and evaluate the level of student preikrences for online examinations. The statistical determinants of student preferences for online testing were identified and quantified using logistic regression analysis. Strategies for the effective use of online examinations arc summarized for potential adopters of online examinations. Key CVorc1.s: online examinations, st~~dent learning. teaching technology, undel-graduatc tcaching JEI, Classification: A22