cssi/SciSciGPT-SciSciNet huggingface dataset:
A lipid molecular marker assessment of sediments from the Northern Gulf of Mexico before and after the passage of Hurricane Lili

Abstract A characterization study of lipid molecular markers was undertaken to identify the provenance of organic matter in surface sediments from the Louisiana Shelf, west of the Atchafalaya River before and after the passage of Hurricane Lili (a category 2 storm) in October 2002. During both sampling periods, terrestrially derived organic matter, as revealed by long chain n-alkanes, terrestrial aquatic hydrocarbon ratio (TARHC) and β-sitosterol, was a predominant component of the organic matter, supporting earlier studies. A petroleum derived unresolved complex mixture (UCM) was detected at each station during both sampling events and displayed no statistically significant difference between inshore and offshore stations. The absence of any relationship between the UCM and the bulk radiocarbon isotopic compositions suggests that petroleum derived organic matter does not significantly control the ages of the sedimentary organic carbon (>2000 years). In addition, sterols, linear, mono- and polyunsaturated fatty acids (FAs) from multiple organic matter sources, including diatoms, dinoflagellates and zooplankton, were also detected at each site. These compounds indicated the sources of organic matter for pre- and post-hurricane samples were similar overall. Surface area-normalized concentrations of n-alkanes and bacterially derived FAs for the pre- and post-hurricane sediments were statistically different between events whereas other parameters such as total sterol and FA concentrations were not.
Conversion of Torgov's Synthesis of Estrone into a Highly Enantioselective and Efficient Process

A very direct and efficient conversion of the achiral Torgov diketone into the natural form of O-methyl estrone is described.
Stochastic Acceleration of Low-Energy Electrons in Plasmas with Finite Temperature

This paper extends our earlier work on the acceleration of low-energy electrons by plasma turbulence to include the effects of finite temperature of the plasma. We consider the resonant interaction of thermal electrons with the whole transverse branch of plasma waves propagating along the magnetic field. We show that our earlier published results for acceleration of low-energy electrons can be applied to the case of finite temperature if a sufficient level of turbulence is present. From comparison of the acceleration rate of the thermal particles to the decay rate of the waves with which they interact, we determine the required energy density of the waves as a fraction of the magnetic energy density, so that a substantial fraction of the background plasma electrons can be accelerated. The dependence of this value on the plasma parameter α = ωpe/Ωe (the ratio of electron plasma frequency to electron gyrofrequency), plasma temperature, and turbulence spectral parameters is quantified. We show that the result is most sensitive to the plasma parameter α. We estimate the required level of total turbulence by calculating the level of turbulence required for the initial acceleration of thermal electrons and that required for further acceleration to higher energies.
Relaxation and free modes of a self-gravitating planet

The relaxation and purely radial free modes of a planet subject to a nonhydrostatic prestress caused by gravity and evidenced by the presence of high mountain ranges and deep abyssal plains are studied. It is shown that there is an infinite set of rheological models of the same type for the planet which have the same relaxation time. Additional information on the behavior of the material is needed to better specify the model. The prestress is shown to shift the period of each purely radial free mode of the planet.
Effect of the twist operator in the D1D5 CFT

The D1D5 CFT has been very useful in the study of black holes. The interac- tion in this theory involves a twist operator, which links together different copies of a free CFT. For the bosonic fields, we examine the action of this twist when it links together CFT copies with winding numbers M and N to produce a copy with winding M + N. Starting with the vacuum state generates a squeezed state, which we compute. Starting with an initial excitation on one of the copies gives a linear combination of excitations on the final state, which we also compute. These results generalize earlier computations where these quantities were computed for the special case M = N = 1. Our results should help in understanding the thermalization process in the D1D5 CFT, which gives the dual of black hole formation in the bulk.
Where do resources come from? a model of resource generation

Although the Resource-Based View of the firm (RBV) continues to gain centrality in the conversation of strategic management, several unanswered questions remain within the emerging paradigm. This article focuses on one of those questions. We propose a causal model of resource generation built around three central constructs: entrepreneurial ability, market context, and organizational context. Entrepreneurial ability generates new asset combinations that are valuable and unique, while market and organizational contexts preserve the value in these new asset combinations by providing barriers to imitation. We build a model and then consider three separate paths for generating idiosyncratic resources within a firm. Organizational values such as control and flexibility influence an organization's ability to develop resources along any given path. The issue of resource generation is particularly relevant for high technology firms, during the time that competition in these industries is driven by the need to continually develop and exploit new sources of competitive advantage.
Digital Adaptive Model following Flight Control

Simple mechanical linkages are often unable to cope with the many control problems associated with high performance aircraft maneuvering over a wide flight envelope. One procedure for retaining uniform handling qualities over such an envelope is to implement a digital adaptive controller. Towards such an implementation an explicit adaptive controller, which makes direct use of online parameter identification, has been developed and applied to the linearized equations of motion for a typical fighter aircraft. The system is composed of an online weighted least squares identifier, a Kalman state filter, and a single stage real model following control law. The corresponding control gains are readily adjustable in accordance with parameter changes to ensure asymptotic stability if the conditions for perfect model following are satisfied and stability in the sense of boundedness otherwise.
A Gluing Algorithm for Distributed Simulation of Multibody Systems

A new gluing algorithm is presented that can be used tocouple distributed subsystem models fordynamics simulation of mechanical systems. Using this gluingalgorithm, subsystem models can be analyzed attheir distributed locations, using their own independent solvers,and on their own platforms. The gluing algorithmdeveloped relies only on information available at the subsysteminterfaces. This not only enables efficientintegration of subsystem models, but also engenders modelsecurity by limiting model access only to the exposedinterface information. These features make the algorithm suitablefor a real and practical distributed simulationenvironment.
Optimal broadcast in all-port wormhole-routed hypercubes

We give an optimal algorithm that broadcasts on an n-dimensional hypercube in O(n/ log/sub 2/ (n+1)) routing steps with wormhole, e-cube routing and all-port communication. Previously, the best algorithm of P.K. McKinley and C. Trefftz (1993) requires [n/2] routing steps. We also give routing algorithms that achieve tight time bounds for n /spl les/7. >
Introduction to rotational-echo, double-resonance NMR

Rotational-echo, double-resonance nuclear magnetic resonance (REDOR) is a magic-angle spinning experiment for measuring internuclear distances between heteronuclear spin pairs. The basic principles of the REDOR technique are presented. The experimental requirements necessary for quantitative REDOR measurements are also provided. ©1998 John Wiley & Sons, Inc. Concepts Magn Reson 10: 277–289, 1998
Inflation induced Planck-size black hole remnants as dark matter

While there exist various candidates, the identification of dark matter remains unresolved. Recently it was argued that the generalized uncertainty principle (GUP) may prevent a black hole from evaporating completely, and as a result there should exist a Planck-size BHR at the end of its evaporation. We speculate that the stability of BHR may be further protected by supersymmetry in the form of extremal black hole. If this is indeed the case and if a sufficient amount of small black holes can be produced in the early universe, then the resultant BHRs can be an interesting candidate for DM. We demonstrate that this is the case in the hybrid inflation model. By assuming BHR as DM, our notion imposes a constraint on the hybrid inflation potential. We show that such a constraint is not fine-tuned. Possible observational signatures are briefly discussed.
Price-based protocols for fair resource allocation: Convergence time analysis and extension to leontief utilities

We analyze several distributed, continuous time protocols for a fair allocation of bandwidths to flows in a network (or resources to agents). Our protocols converge to an allocation that is a logarithmic approximation, simultaneously, to all canonical social welfare functions (i.e., functions that are symmetric, concave, and nondecreasing). These protocols can be started in an arbitrary state. Although a similar protocol was known before, it only applied to the simple bandwidth allocation problem, and its stability and convergence time were not understood. In contrast, our protocols also apply to the more general case of Leontief utilities, where each user may place a different requirement on each resource. Furthermore, we prove that our protocols converge in polynomial time. The best convergence time we prove is O (n log ncMAXaMAX/cMINaMIN), where n is the number of agents in the network, cMAX and cMIN are the maximum and minimum capacity of the links, and amax, amin are respectively the largest and smallest Leontief coefficients. This time is achieved by a simple Multiplicative Increase, Multiplicative Decrease (MIMD) protocol that had not been studied before in this setting. We also identify combinatorial properties of these protocols that may be useful in proving stronger convergence bounds. The final allocations by our protocols are supported by usage-sensitive dual prices that are fair in the sense that they shield light users of a resource from the impact of heavy users. Thus, our protocols can also be thought of as efficient distributed schemes for computing fair prices.
The Range of Five-Coordinate Group 13-Salen Compounds

The present publication will provide an overview of the formation of selected five-coordinate aluminum, gallium, and indium compounds.
Multi-channel Analysis of Surface Waves (MASW) in Karst Terrain, Southwest Georgia: Implications for Detecting Anomalous Features and Fracture Zones

ABSTRACT Multi-channel analysis of surface waves (MASW) was used to map bedrock topography, image anomalies in the soil overburden, and detect variations in the degree of limestone weathering in covered, karst terrain near Albany, Georgia. Surface-wave data were acquired along seven parallel lines and two perpendicular cross-lines. Two surveys using a hammer and moving van-source were conducted to address the trade-off between lateral resolution and depth penetration. Resolution matrices show that the depth ranges most effectively imaged are 0.5–4 m for half-spread hammer data, 3–12 m for full-spread hammer data, and 8–20 m for van-source data. A steep S-velocity gradient marked by the 350 m/s contour at depths of 9–12 m is interpreted as the bedrock surface, in agreement with coincident borehole data. The models indicate variations within limestone bedrock (S-velocity: 350–700 m/s) and anomalous zones within the sandy-clay overburden. Standard penetration tests at two locations 45-m apart confirm variati...
Ab initio no-core shell model and microscopic reactions: Recent achievements

We report on recent microscopic calculations of reaction properties based upon the nuclear structure of the ab initio no-core shell model (NCSM).
Synthesis of aminoshikimic acid.

5-Amino-5-deoxyshikimic acid (aminoshikimic acid) was synthesized from glucose using recombinant Amycolatopsis mediterranei and also synthesized by a tandem, two-microbe route employing Bacillus pumilus and recombinant Escherichia coli.
Are Morally Motivated Decision Makers Insensitive to the Consequences of Their Choices

Is morally motivated decision making different from other kinds of decision making? There is evidence that when people have sacred or protected values (PVs), they reject trade-offs for secular values (e.g., "You can't put a price on a human life") and tend to employ deontological rather than consequentialist decision principles. People motivated by PVs appear to show quantity insensitivity. That is, in trade-off situations, they are less sensitive to the consequences of their choices than are people without PVs. The current study examined the relation between PVs and quantity insensitivity using two methods of preference assessment: In one design, previous results were replicated; in a second, PVs were related to increased quantity sensitivity. These and other findings call into question important presumed properties of PVs, suggesting that how PVs affect willingness to make trade-offs depends on where attention is focused, a factor that varies substantially across contexts.
A Least Squares Solution for Use in the Six-Port Measurement Technique

Although based on the use of simple amplitude detectors, it is possible to obtain complex values of reflection coefficient, via the six-port technique, from the intersection of three circles in the complex plane. In a typical case, the circle centers are detemined primarily by the six-port design and are nominally constant, while the radii are proportional to the square root of the ratio of the output of three of the detectors to a fourth one. As a practical matter, however, these circles will not intersect in a point because of noise or other errors in the detectors.This paper develops a presedure for choosing Gamma in this context. Moreover, the question of what may be inferred about the system performance from the extent of this intersection failue is briefly considered.
Topotactic Transformations of Metal–Organic Frameworks to Highly Porous and Stable Inorganic Sorbents for Efficient Radionuclide Sequestration

Innovative solid-phase sorbent technologies are needed to extract radionuclides from harsh media for environmental remediation and in order to close the nuclear fuel cycle. Highly porous inorganic materials with remarkable sorptive properties have been prepared by topotactic transformations of metal–organic frameworks (MOFs) using both basic and acidic solutions. Treatment of Ti and Zr nanoMOFs with NaOH, Na3PO4, and H3PO4 yields Ti and Zr oxides, oxyphosphates, and phosphates via sacrificial removal of the organic ligands. This controlled ligand extraction process results in porous inorganic materials, which preserve the original MOF morphologies and impart useful surface functionalities, but are devoid of organic linkers. Structural investigation by X-ray absorption spectroscopy reveals preservation of the coordination environment of the scattering metal. Changing the MOF template introduces different metal and structural possibilities, while application of different digest solutions allows preparation ...
The Income Gradient and Distribution-Sensitive Measures of Overweight in the U.S.

This paper considers alternate measures of overweight in the U.S. that are sensitive to changes in the body-mass index (BMI) distribution, more robust to measurement error and continuous in the body-mass index (BMI) at the overweight threshold. The measures suggest that standard prevalence rates may be understating the severity of the problem. Since 1971, overweight prevalence has increased by 40% while the distribution-sensitive measure has increased by 174%. They also provide some useful insight into socioeconomic differences in overweight. For example, overweight prevalence rates for the poor and the rich have been very similar over the last 30 years, with the rich have a slightly higher rate in the most recent 2001- 2002 data. In contrast, the distribution sensitive measures reveal that overweight rich people exceed the overweight threshold by 23% while the overweight poor exceed the threshold by a much greater amount (31%) on average.
Optimal Scheduling of Biochemical Analyses on Digital Microfluidic Systems

Digital microfluidic systems (DMFS) are an emerging class of lab-on-a-chip systems that manipulate individual droplets of chemicals on a planar array of electrodes. The biochemical analyses are performed by repeatedly moving, mixing, and splitting droplets on the electrodes. Mixers and storage units, composed of electrodes, are two important functional resources. Mixers perform droplet mixing and splitting operations, while storage units store droplets that have been produced for subsequent mixings. In this paper, we focus on minimizing the completion time of biochemical analyses by exploiting the binary tree representation of analyses to schedule mixing operations. Using pipelining, we overlap mixing operations with input and transportation operations. We find the lower bound of the mixing completion time based on the tree structure of input analyses, and calculate the minimum number of mixers Mlb required to achieve the lower bound. We present a scheduling algorithm for the case with a specified number of mixers M , and prove it is optimal to minimize the mixing completion time. We also analyze resource constraint issues for two extreme cases. For the case with just one mixer, we prove that all schedules that keep the mixer busy at all times result in the same mixing completion time and then design algorithms for scheduling and to minimize the number of storage units. For the case with zero storage units, we find the minimum number of mixers required. We extend our analyses and algorithms assuming identical mixing durations to the case of different mixing durations. Finally, we illustrate the benefits of our scheduling methods on an example of DNA polymerase chain reaction (PCR) analysis.
'Place Prosperity vs People Prosperity' Revisited: An Old Issue with a New Angle

'Place prosperity vs people prosperity' is a familiar shorthand expression of various issues in designing national policies to assist persons and places that are economically depressed. The paper reviews some traditional issues, including those introduced by Louis Winnick, who coined the phrase in the title, and also introduces some new ones. It suggests that 'sense of place' is relevant to the policy debate, because sense of place is a factor in regional and local identity and is an important form of intangible capital that has positive externalities. The paper relies on principles of benefit-cost analysis, and it notes that a concern for the sense of place is consistent with some recent developments in economic theory, namely in the theory of household production and theories of 'fairness' and community values. It also includes an appreciation of the work of Ben Chinitz, whose emphasis on 'supply' in regional analysis is consistent with a respect for the sense of place and is also relevant to a discussi...
An out-of-equilibrium model of the distributions of wealth

The distribution of wealth among the members of a society is herein assumed to result from two fundamental mechanisms: trade and investment. An empirical distribution of wealth shows an abrupt change between the low–medium range, that may be fitted by a non-monotonic function with an exponential-like tail such as a gamma distribution, and the high wealth range, that is well fitted by a Pareto or inverse power-law function. We demonstrate that an appropriate trade-investment model, depending on three adjustable parameters associated with the total wealth of a society, a social differentiation among agents, and economic volatility referred to as investment, can successfully reproduce the distribution of empirical wealth data in the low, medium and high ranges. Finally, we provide an economic interpretation of the mechanisms in the model and, in particular, we discuss the difference between classical and neoclassical theories regarding the concepts of value and price. We consider the importance that out-of-e...
Entropic Latent Variable Integration via Simulation

This paper introduces a general method to convert a model defined by moment conditions that involve both observed and unobserved variables into equivalent moment conditions that involve only observable variables. This task can be accomplished without introducing infinite-dimensional nuisance parameters using a least favorable entropy-maximizing distribution. We demonstrate, through examples and simulations, that this approach covers a wide class of latent variables models, including some game-theoretic models and models with limited dependent variables, interval-valued data, errors-in-variables, or combinations thereof. Both point- and set-identified models are transparently covered. In the latter case, the method also complements the recent literature on generic set-inference methods by providing the moment conditions needed to construct a generalized method of moments-type objective function for a wide class of models. Extensions of the method that cover conditional moments, independence restrictions, and some state-space models are also given.
Flash vacuum pyrolysis of 2-diazo-8-oxabicyclo[3.2.1]Oct-6-en-3-ones. A new method for the preparation of propadienones.

Abstract When diazoketones 3a and 3b are pyrolysed at 430°C and 10 −4 torr, they undergo loss of N 2 followed by Wolff rearrangement and loss of furan by retro Diels-Alder reaction to yield the desired propadienones 1 ( a,b ). If argon is added to the pyrolysate mixture, these reactive compounds can be trapped under matrix isolation conditions at 22 K and observed by FTIR. Upon photolysis, 1b yields carbon monoxide and 2-butyne.
Reliable kinetic Monte Carlo simulation based on random set sampling

Kinetic Monte Carlo (KMC) method has been widely used in simulating rare events such as chemical reactions or phase transitions. Yet lack of complete knowledge of transitions and the associated rates is one major challenge for accurate KMC predictions. In this paper, a reliable KMC (R-KMC) mechanism is proposed in which sampling is based on random sets instead of random numbers to improve the robustness of KMC results. In R-KMC, rates or propensities are interval estimates instead of precise numbers. A multi-event algorithm based on generalized interval probability is developed. The weak convergence of the multi-event algorithm towards the traditional KMC is demonstrated with a generalized Chapman---Kolmogorov equation.
Late-Occurring Vancomycin-Associated Acute Kidney Injury in Children Receiving Prolonged Therapy

Background: Acute kidney injury (AKI) in patients receiving vancomycin has been associated with trough concentrations ≥15 mg/L and longer therapy duration. The objective of this study was to determine the incidence and factors associated with late AKI in children receiving ≥8 days of vancomycin therapy. Methods: Children aged 30 days to 17 years who were admitted to our institution and received intravenous vancomycin for at least 8 days during January to December of 2007 and 2010 and had a suspected or proven gram-positive infection were included. Late AKI was categorized as AKI occurring after the first 7 days of therapy and within 48 hours following vancomycin discontinuation. The primary outcome was incidence of late AKI as determined by modified pRIFLE criteria. Results: One-hundred sixty-seven patients were included, with a median (interquartile range) age (years) and weight (kg) of 2 (1-7) and 12.5 (8.9-23.8). Late AKI was identified in 12.6% (21/167). A higher percentage of late AKI patients receiv...
Quartic del Pezzo surfaces over function fields of curves

We classify quartic del Pezzo surface fibrations over the projective line via numerical invariants, giving explicit examples for small values of the invariants. For generic such fibrations, we describe explicitly the geometry of spaces of sections to the fibration, and mappings to the intermediate Jacobian of the total space. We exhibit examples where these are birational, which has applications to arithmetic questions, especially over finite fields.
A comparison of cyclohexanone and tetrahydro-4H-thiopyran-4-one 1,1-dioxide as pharmacophores for the design of peptide-based inhibitors of the serine protease plasmin.

The plasminogen system is important in the proteolytic cascade that facilitates angiogenesis, a process that is essential for tumor growth and metastasis. The serine protease plasmin has a central role in the plasminogen system. This protease acts by degrading several components of the basement membrane and by activating other proteases. Therefore, inhibition of plasmin may be an effective method for blocking angiogenesis and, as a result, inhibiting the growth of primary tumors and secondary metastases. Three pairs of plasmin inhibitors were synthesized to compare the relative potency of inhibitors that are based upon a cyclohexanone or a tetrahydro-4H-thiopyran-4-one 1,1-dioxide nucleus. Compounds 1, 3, and 5 were cyclohexanone-based inhibitors, whereas compounds 2, 4, and 6 were tetrahydro-4H-thiopyran-4-one 1,1-dioxide-based inhibitors. Compounds 5 and 6 are reasonable inhibitors with IC50 values of 25 and 5.5 μM, respectively. Comparisons of the IC50 values of the three pairs show that the electron-w...
Composition profiling of graded dielectric function materials by spectroscopic ellipsometry

Abstract In this work, the characterization of graded composition layers in transparent materials by spectroscopic ellipsometry (SE) is described. The sensitivity limits were modeled by comparing calculated spectra for samples with and without diffusion profiles at the sample surface for several glass compositions. It was found that for known index profile shapes, the depth sensitivity can be quite high. The sensitivity of the technique increases as the diffusion depth and refractive index contrast increases. The accuracy of the thickness determination depends on the total thickness of the graded layer; for a given system, the accuracy of the composition measurements did not depend on the surface concentration. Leached alkali-aluminosilicate and modified lead silicate glasses were examined by SE to experimentally confirm the modeling predictions on the composition depth profiling. Extremely good correlation between the SE-determined depth profile and SIMS measurements on similar samples was obtained for the case of the modified lead silicate glass. For the aluminosilicate glass, simultaneous roughening of the glass surface during etching makes composition profiling more difficult.
Why we (usually) don't have to worry about multiple comparisons

Abstract Applied researchers often find themselves making statistical inferences in settings that would seem to require multiple comparisons adjustments. We challenge the Type I error paradigm that underlies these corrections. Moreover we posit that the problem of multiple comparisons can disappear entirely when viewed from a hierarchical Bayesian perspective. We propose building multilevel models in the settings where multiple comparisons arise. Multilevel models perform partial pooling (shifting estimates toward each other), whereas classical procedures typically keep the centers of intervals stationary, adjusting for multiple comparisons by making the intervals wider (or, equivalently, adjusting the p values corresponding to intervals of fixed width). Thus, multilevel models address the multiple comparisons problem and also yield more efficient estimates, especially in settings with low group-level variation, which is where multiple comparisons are a particular concern.
Efficient estimation and stratified sampling

Abstract In this paper we investigate estimation of a class of semi-parametric models. The part of the model that is not specified is the marginal distribution of the explanatory variables. The sampling is stratified on the dependent variables, implying that the explanatory variables are no longer exogenous or ancillary. We develop a new estimator for this estimation problem and show that it achieves the semi-parametric efficiency bound for this case. In addition we show that the estimator applies to a number of sampling schemes that have previously been treated separately.
Restructuring with What Success? A Case Study of Russian Firms

This case study of enterprise restructuring utilizes data collected from thirty-two former state-owned firms in Taganrog, Russia, in the summer and fall of 1999. These data are used to construct three composite measures of enterprise restructuring. When defined broadly to include several dimensions of the restructuring process, the “restructuring threshold” is achieved by half of the privatized firms participating in the project. The firms achieving this threshold are distributed across all industries included in the sample. Regardless of the composite measure used, more than one-third of the former state-owned firms participating in this project attained the “active” restructuring designation. The results indicate that (1) production assortment changes appear to be ongoing among those firms engaged in restructuring activities, (2) employment changes appear to involve a mixed strategy with regard to timely wage payments, workforce size, and the benefits package; and (3) outsider ownership is more prevalent among the group of firms designated as restructuring than among those firms that failed to achieve the “restructuring threshold.” To put into perspective the economic and business environment in which these former state-owned firms operate, a comparison is made to a group of de novo firms that were surveyed under the auspices of the same project.
Measuring Residential Real Estate Risk and Return

This article explains how common misconceptions about residential real estate returns contribute to unrealistic expectations about house price appreciation. The article evaluates several comprehensive ways of computing residential real estate returns and discusses the relation between real estate return and risk. We review the role of real estate in household portfolios, the overall economy, and the financial crisis and discuss why decline in the real estate market imposes economy-wide risks.
A novel rearrangement reaction accompanying alkyl metaphosphate extrusion on low-temperature photolysis of 2,3-oxaphosphabicyclo[2.2.2]octene derivatives

Abstract On photolysis in propionitrile or THF solution at −75°, three phosphonates (1-adamantyl, neopentyl, and ethyl as O-substituents) with the 2,3-oxaphosphabicyclo[2,2,2] octene ring system underwent extensive rearrangement accompanying the usual result at room temperature of metaphosphate extrusion. The rearrangement product contains a cyclopropane ring, arising from detachment of the bridgehead-bound oxygen followed by attack on the double bond and subsequent ring closure. The rearrangement does not occur with related phosphonamides but has been detected with a phosphine oxide.
Content management in a mobile ad hoc network: beyond opportunistic strategy

We study the challenging problem of strategic content placement in a dynamic MANET. Existing content placement techniques cannot cope with such network dynamics since they are designed for fixed networks. Opportunistic caching approaches are insufficient as they do not actively manage contents for certain goals. In this paper, we present a novel content management approach, called LACMA that leverages the location information available to mobile devices via GPS. The main insight behind LACMA is to bind data to geographic location as opposed to network nodes. This location-based strategy decouples the content placement problem from the changing network topology, and allows us to design an optimisation framework even in a dynamic MANET environment. We present key components of LACMA used for strategic content placement and content-location binding through proactive content push. We evaluate LACMA and compare its performance with existing caching schemes and show that LACMA considerably outperforms existing schemes over a wide range of scenarios.
Speed-of-light limitations in passive linear media

We prove that well-known speed-of-light restrictions on electromagnetic energy velocity can be extended to a new level of generality, encompassing even nonlocal chiral media in periodic geometries, while at the same time weakening the underlying assumptions to only passivity and linearity of the medium (either with a transparency window or with dissipation). As was also shown by other authors under more limiting assumptions, passivity alone is sufficient to guarantee causality and positivity of the energy density (with no thermodynamic assumptions). Our proof is general enough to include a very broad range of material properties, including anisotropy, bianisotropy (chirality), nonlocality, dispersion, periodicity, and even delta functions or similar generalized functions. We also show that the ``dynamical energy density'' used by some previous authors in dissipative media reduces to the standard Brillouin formula for dispersive energy density in a transparency window. The results in this paper are proved by exploiting deep results from linear-response theory, harmonic analysis, and functional analysis that had previously not been brought together in the context of electrodynamics.
Instability of Thallium‐Containing Superconductor Phases in Isothermal Equilibrium with Thallium Oxide

Knowledge of the equilibrium conditions under which the superconducting phases in the Tl-Ca-Ba-Cu-O system are stable would enable the controlled preparation of these materials. Isothermal equilibrium between samples in this quaternary system and Tl2O vapor from a condensed thallium oxide source has been studied. None of the superconductor phases coexisted in equilibrium with thallium oxide under the conditions employed. Instead, two previously unknown ternary thallium-calcium-barium oxides and one previously unknown thallium-calcium oxide were observed. The equilibrium phase assemblage at temperatures between 825° and 925°C consisted of the most thallium-rich ternary oxide plus CuO, although small amounts of the other thallium-rich phases may be required to balance stoichiometry. The vapor pressure of Tl2O established by pure, condensed thallium oxide clearly exceeds the stability limit for the superconductor phases. If the thallium-containing superconductors are stable phases at high temperature, they will exist over some range of lower Tl2O partial pressure.
Forward engineering of synthetic bio-logical AND gates

Abstract The field of synthetic biology has produced genetic circuits capable of emulating functional paradigms seen in digital electronic circuits. Examples are bistable switches, oscillators, and logic gates. The present work combines detailed mechanistic-kinetic models and stochastic simulation techniques as well as the techniques of in vivo molecular biology to study the potential of a synthetic, single promoter AND gate. This device is composed of elements of the tet , lac , and λ-phage promoters and is responsive to the commonly used inducers IPTG and aTc, producing GFP as an output signal. The quantitative behavior of the AND gate phenotype is studied both in numero and in vivo as a function of promoter topology. The model is constructed from kinetic data obtained from the literature and yields clearly defined ON/OFF logical behavior at realistic inducer concentrations. These behaviors are matched with observed in vivo data obtained through fluorescence-activated cell sorting. The effect of incomplete repression by weaker LacI repressor is also investigated and quantified. The simulation results, coupled with in vivo data, not only identify important design degrees of freedom, but also provide parameters that can be used to guide future synthetic designs using these common regulatory elements.
How Teaching World Religions Brought a Truce to the Culture Wars in Modesto, California.

Despite a growing consensus among scholars and activists about the importance of religion, proposals for teaching about it have often been a source of division rather than unity in American public school districts. Faced with familiar cultural conflicts, Modesto, California, chose to become the first public school district in the USA to require all high school students to take an extended and independent course in world religions. The results of the first, large‐scale empirical research on the effects of teaching about religion in USA public schools provides evidence that Modesto’s bold approach was worth the risk. Surveys and interviews administered to students show statistically significant increases in students’ knowledge about other religions, and levels of passive tolerance – willingness to refrain from discrimination – and active tolerance – willingness to act to counter discrimination. The course has not been the subject of lawsuits or complaints by parents and has gained acceptance among all of Mo...
Validation of the mental alternation test with the mini-mental state examination in geriatric psychiatric inpatients and normal controls

The Mental Alternation Test (MAT) is a bedside test of cognition that was used for the detection of human immunodeficiency virus (HIV)-related cognitive impairment. It has been shown to have good reproducibility and inter-rater reliability, and takes only 60 seconds to administer. To assess the utility of the MAT in the geriatric primary care and geriatric psychiatric settings, we used the Mini-Mental State Examination (MMSE) as a further validation of the test. This cohort study included 20 geriatric psychiatric inpatients, 15 normal geriatric controls, and four normal adult controls. The study was conducted within the inpatient psychiatric unit of a referral hospital. Scores on the MAT and the MMSE were compared using correlation calculations. Test score means and standard deviations were computed for each study population. Test score cutoffs derived from a previous study were used to determine the sensitivity and specificity of the MAT as compared with the MMSE. The MAT score was found to correlate significantly with the MMSE score (r =.84, P <.0001). Scores on the MAT were predictive of scores on the MMSE, with a sensitivity of 91% and a specificity of 100%. We conclude that MAT is a good test of cognition in both geriatric primary care and geriatric psychiatric populations. It has both good specificity and sensitivity, and its ease of administration and inter-rater reliability make it a useful diagnostic tool for identifying those patients who may need further cognitive evaluations.
Dark matter caustics.

The late infall of cold dark matter onto an isolated galaxy such as our own produces flows with definite velocity vectors at any physical point in the galactic halo. It also produces caustics which are places where the dark matter density is very large. The outer caustics are topological spheres whereas the inner caustics are rings. The self-similar model of galactic halo formation predicts that the caustic ring radii a n follow the approximate law \({a_{{n \sim {{1} \left/ {n} \right.}}}}\). In a recent study of 32 extended and well-measured galactic rotation curves, we found evidence for this law.
Short-time transport properties of bidisperse suspensions and porous media: a Stokesian Dynamics study

We present a comprehensive computational study of the short-time transport properties of bidisperse hard-sphere colloidal suspensions and the corresponding porous media. Our study covers bidisperse particle size ratios up to 4 and total volume fractions up to and beyond the monodisperse hard-sphere close packing limit. The many-body hydrodynamic interactions are computed using conventional Stokesian Dynamics (SD) via a Monte-Carlo approach. We address suspension properties including the short-time translational and rotational self-diffusivities, the instantaneous sedimentation velocity, the wavenumber-dependent partial hydrodynamic functions, and the high-frequency shear and bulk viscosities and porous media properties including the permeability and the translational and rotational hindered diffusivities. We carefully compare the SD computations with existing theoretical and numerical results. For suspensions, we also explore the range of validity of various approximation schemes, notably the pairwise additive approximations with the Percus-Yevick structural input. We critically assess the strengths and weaknesses of the SD algorithm for various transport properties. For very dense systems, we discuss in detail the interplay between the hydrodynamic interactions and the structures due to the presence of a second species of a different size.
Prognostics of Machine Condition Using Energy Based Monitoring Index and Computational Intelligence

A study is presented on applications of computational intelligence (CI) techniques for monitoring and prognostics of machinery conditions. The machine condition is assessed through an energy-based feature, termed as "energy index," extracted from the vibration signals. The progression of the "monitoring index" is predicted using the CI techniques, namely, recursive neural network (RNN), adaptive neurofuzzy inference system (ANFIS), and support vector regression (SVR). The proposed procedures have been evaluated through benchmark data sets for one-step-ahead prediction. The prognostic effectiveness of the techniques has been illustrated through vibration data set of a helicopter drivetrain system gearbox. The prediction performance of SVR was better than RNN and ANFIS. The improved performance of SVR can be attributed to its inherently better generalization capability. The training time of SVR was substantially higher than RNN and ANFIS. The results are helpful in understanding the relationship of machine conditions, the corresponding indicating feature, the level of damage or degradation, and their progression.
INC: a language for incremental computations

An incremental computation is one that is performed repeatedly on nearly identical inputs. Incremental computations occur naturally in many environments, such as compilers, language-based editors, spreadsheets, and formatters. This article describes a proposed tool for making it easy to write incremental programs. The tool consists of a programming language, INC, and a set of compile-time transformations for the primitive elements of INC. A programmer defines an algorithm in INC without regard to efficient incremental execution. The transformations automatically convert this algorithm into an efficient incremental algorithm. INC is a functional language. The implementation of an INC program is a network of processes. Each INC function is transformed into a process that receives and transmits messages describing changes to its inputs and outputs. We give an overview to the language and illustrate the incremental techniques employed by INC. We present the static and incremental complexity bounds for the primitive INC functions. We also present some example programs illustrating INC's flexibility.
On the jets associated with galactic superluminal sources

Recent observations of GRS 1915+105 and GRO J1655+40 reveal superluminal motions in Galactic sources. This Letter examines the physical conditions within these Galactic sources, their interaction with their environment, and their possible formation, and contrasts them with their extragalactic counterparts. In particular, e+-e- and e-p jets are contrasted; constraints on particle acceleration in the jets are imposed using X-ray and radio observations; and the γ-ray flux from e+-e- jets expected at EGRET energies and the flux in infrared lines from an e-p jet are estimated. It is also suggested that these sources may exhibit low-frequency radio lobes extending up to several hundred parsecs in size, strong, soft X-ray absorption during the birth of the radio components, and emission-line strengths anticorrelated with the X-ray flux. The implications for other X-ray transients are briefly discussed.
Improved Mean-flow Solution for Slab Rocket Motors with Regressing Walls

The Navier‐Stokes equations are solved to obtain an approximate description of the mean e ow in a slab rocket motor with two evenly regressing walls. The scope is limited to two-dimensional incompressible and chemically nonreactive viscous e ow. The transformed governing equation is solved numerically, using e nite differences, and asymptotically, using variation of parameters and small parameter perturbations in the blowing Reynolds number R. Results are correlated and compared via variations in R and the dimensionless wall regression rate. For hard blowing and moderate regression rates the effect of wall motion on the velocity is found to be small. Conversely,forfast-burningpropellants,suchasthosebeing developed forhigh-accelerationvehicles,regressioneffects seem ine uential. Inclusion of viscous dissipation is also found to be important in assessing the total e ow vorticity, especially when R<102. The current geometric cone guration is relevant to motor simulations using ducted channels with porous walls. For validation purposes comparisons with numerical solutions are carried out alongside end-process verie cations. Because the resulting model incorporates viscosity and wall motion, it allows for an improved description of the unsteady acoustico-vortical solution whose assessment is strongly ine uenced by the mean e ow.
Discovery of the cadmium isotopes

Thirty-seven cadmium isotopes have been observed so far and the discovery of these isotopes is discussed here. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.
Compactness for manifolds and integral currents with bounded diameter and volume

By Gromov’s compactness theorem for metric spaces, every uniformly compact sequence of metric spaces admits an isometric embedding into a common compact metric space in which a subsequence converges with respect to the Hausdorff distance. Working in the class of oriented k-dimensional Riemannian manifolds (with boundary) and, more generally, integral currents in metric spaces in the sense of Ambrosio–Kirchheim and replacing the Hausdorff distance with the filling volume or flat distance, we prove an analogous compactness theorem in which however we only assume uniform bounds on volume and diameter.
Contortions of encapsulated alkyl groups.

Rotors are recalled as early molecular devices that transmit information through changes in conformation. Specific cases involve bipyridyls and biphenyls in which the biaryl bond acts as a fulcrum to relay applied stresses from one site to another. New types of molecular stress encountered by encapsulated molecules are identified—including bending, straightening, squeezing, grinding and compression. For flexible molecules in reversibly formed capsules a fluid model of recognition is proposed that is neither lock-and-key nor induced fit. Instead, the guest assumes the shape that best fills the available space, even if contortions to higher energy conformations are required. For encapsulated alkanes, a delicate balance of attraction and repulsion exists when the size of a guest molecule approaches the space available to it. The complexes are analyzed by both NMR and computational methods and detailed maps of the host–guest interfaces in solution are provided. The reversible transition of an encapsulated alkane between a compressed, coiled conformation and a relaxed, extended one is described. The system is a spring-loaded molecular device under the control of acids and bases that offers an alternative to the rotors of current molecular machinery.