cssi/SciSciGPT-SciSciNet huggingface dataset:
Robustness of CDK2 in triggering cellular senescence based on probability of DNA-damaged cells passing G1/S checkpoint

Recent experiments have shown that cellular senescence, a mechanism employed by cells for thwarting cell proliferation, plays an important role in protecting cells against cancer; therefore, a deeper understanding of cellular senescence can lead to effective cancer treatment. Inhibition of CDK2 is thought to be the critical trigger for cellular senescence. In this study, we first implement a mathematical model of G1/S transition involving the DNA-damage pathway and show that cellular senescence can be achieved by lowering CDK2. The robustness of CDK2 in triggering cellular senescence is determined from the probability (β) of DNA-damaged cells passing G1/S checkpoint for normal CDK2 and CDK2-deficient situations based on different thresholds of the peak time of two important biomarkers, CycE and E2F. The comparison of the values of β under the normal CDK2 and lower CDK2 levels reveals that reducing CDK2 levels can decrease the percentage of damaged cells passing G1/S checkpoint; more importantly, 50% reduction of CDK2 achieves 65% reduction in the percentage of damaged cells passing the G1/S checkpoint. These results point out that the developed model can highlight the possibility of lowering the bar for cellular senescence by reducing CDK2 levels. The results of investigation of β for the different thresholds of the peak times of other biomarkers show that β is insensitive to these perturbations of the peak time indicating that CDK2 activity is robust in lowering the senescence bar for low and high levels of DNA-damage. Furthermore, a mathematical formulation of robustness indicates that the robustness of CDK2 -triggered senescence increases with decreasing levels of CDK2, and is slightly greater for low-level DNA damage condition.
Private data release via learning thresholds

This work considers computationally efficient privacy-preserving data release. We study the task of analyzing a database containing sensitive information about individual participants. Given a set of statistical queries on the data, we want to release approximate answers to the queries while also guaranteeing differential privacy---protecting each participant's sensitive data.Our focus is on computationally efficient data release algorithms; we seek algorithms whose running time is polynomial, or at least sub-exponential, in the data dimensionality. Our primary contribution is a computationally efficient reduction from differentially private data release for a class of counting queries, to learning thresholded sums of predicates from a related class.We instantiate this general reduction with algorithms for learning thresholds, obtaining new results for differentially private data release. As two examples, taking {0, 1}d to be the data domain (of dimension d), we obtain differentially private algorithms for:1. Releasing all k-way conjunction counting queries (or k-way contingency tables). For any given k, the resulting data release algorithm has bounded error as long as the database is of size at least dO [EQUATION] (ignoring the dependence on other parameters). The running time is polynomial in the database size. The best sub-exponential time algorithms known prior to our work required a database of size O (dk/2) [Dwork McSherry Nissim and Smith 2006].2. Releasing any family of counting queries that is specified by a constant depth AC0 predicate. This algorithm releases accurate answers to a (1 − γ)-fraction of the queries in the family. For any γ ≥ quasipoly(1/d), the algorithm has bounded error as long as the database is of size at least quasipoly(d) (again ignoring the dependence on other parameters). The running time is quasipoly(d).The first learning algorithm uses techniques for representing thresholded sums of predicates as low-degree polynomial threshold functions. The second learning algorithm is based on a result of Jackson Klivans and Servedio [JKS 2002], and utilizes Fourier analysis of the database viewed as a function mapping queries to answers.
A Unique Informationally Efficient Allocation Mechanism In Economies With Consumption Externalities

This article investigates the informational requirements of resource allocation processes in pure exchange economies with consumption externalities. It is shown that the distributive Lindahl mechanism has a minimal informational size of the message space, and thus it is informationally the most efficient allocation process that is informationally decentralized and realizes Pareto-efficient allocations over the class of economies that include nonmalevolent economies. Furthermore, it is shown that the distributive Lindahl mechanism is the unique informationally efficient decentralized mechanism that realizes Pareto-efficient and individually rational allocations over a certain class of nonmalevolent economies.
Nonlinear Stabilization via Control Lyapunov Measure

This paper is concerned with computational methods for Lyapunov-based stabilization of an attractor set of a nonlinear dynamical system. Based upon a stochastic representation of deterministic dynamics, a Lyapunov measure is used for these purposes. The paper poses and solves the co-design problem of jointly obtaining a control Lyapunov measure and a state feedback controller. The computational framework employs set-oriented numerical techniques. Using these techniques, the resulting co-design problem is shown to lead to a finite number of linear inequalities. These inequalities determine the feasible set of the solutions to the co-design problem. A particular solution can be efficiently obtained using methods of linear programming.
Parameterization based on randomized quasi-Monte Carlo methods

We present a theoretical framework where any randomized quasi-Monte Carlo method can be viewed and analyzed as a parameterization method for parallel quasi-Monte Carlo. We present deterministic and stochastic error bounds when different processors of the computing environment run at different speeds. We implement two parameterization methods, both based on randomized quasi-Monte Carlo, and apply them to pricing digital options and collateralized mortgage obligations. Numerical results are used to compare the parameterization methods by their parallel performance as well as their Monte Carlo efficiency.
Self-aggregation of convection in long channel geometry

Cloud cover and relative humidity in the Tropics are strongly influenced by organized atmospheric convection, which occurs across a range of spatial and temporal scales. One mode of organization that is found in idealized numerical modelling simulations is self-aggregation, a spontaneous transition from randomly distributed convection to organized convection despite homogeneous boundary conditions. We explore the influence of domain geometry on the mechanisms, growth rates and length-scales of self-aggregation of tropical convection. We simulate radiative–convective equilibrium with the System for Atmospheric Modeling (SAM), in a non-rotating, highly elongated three-dimensional (3D) channel domain of length >104 km, with interactive radiation and surface fluxes and fixed sea-surface temperature varying from 280–310 K. Convection self-aggregates into multiple moist and dry bands across this full range of temperatures. As convection aggregates, we find a decrease in upper tropospheric cloud fraction but an increase in lower tropospheric cloud fraction; this sensitivity of clouds to aggregation agrees with observations in the upper troposphere but not in the lower troposphere. An advantage of the channel geometry is that a separation distance between convectively active regions can be defined; we present a theory for this distance based on boundary layer. We find that surface fluxes and radiative heating act as positive feedback mechanisms, favouring self-aggregation, but advection of moist static energy acts as a negative feedback, opposing self-aggregation, for nearly all temperatures and times. Early in the process of self-aggregation, surface fluxes are a positive feedback at all temperatures, shortwave radiation is a strong positive feedback at low surface temperatures but weakens at higher temperatures and longwave radiation is a negative feedback at low temperatures but becomes a positive feedback for temperatures greater than 295–300 K. Clouds contribute strongly to the radiative feedback, especially at low temperatures.
Wing Drag Prediction and Decomposition

A wake integration methodology to predict the aerodynamic characteristics of three-dimensional wings in viscous subsonic and transonic flows is presented. Results indicate that wake integration is viable as a method of drag prediction and, compared to surface integration, has the added benefit of being able to provide a decomposition of the total drag into its physical components of profile, induced, and wave drag for a wing in viscous, transonic flow. Future work will involve using wake integration on postprocess flows about more complex configurations for which this study provides a sound basic framework.
BATS: Budget-Constrained Autoscaling for Cloud Performance Optimization

Autoscaling has become an integral feature of cloud computing services, allowing users to dynamically scale the cloud resources on demand for both performance and cost. Moreover, recent survey shows the importance of satisfying long-term budget constraints (e.g., monthly or yearly) for cloud users. However, meeting such constraints while optimizing delay performance is challenging: it requires the knowledge of complete offline information such as workload demand over the entire budgeting period, which is difficult to predict accurately. This paper proposes a new autoscaling system, BATS, which optimizes delay performance while meeting long-term budget constraints using only past and instantaneous workload information. Analytically, we prove that, for arbitrary workload arrival, the autoscaling algorithm of BATS achieves close-to-optimal performance even compared to the optimal solution that has complete offline information. Empirically, we build BATS autoscaler as a user-friendly service for running applications on Windows Azure. The experimental results show that BATS achieves both lower cost and less delay compared with the state-of-art threshold-based autoscaling solutions. We also run simulation studies to complement the implementation results, demonstrating the effectiveness, scalability and robustness of BATS for reducing both average and tail latency under various workload scenarios.
Enrichment of the Dust-to-Gas Mass Ratio in Bondi/Jeans Accretion/Cloud Systems due to Unequal Changes in Dust and Gas Incoming Velocities

The ratio of the Bondi and Jeans lengths is used to develop a cloud-accretion model that describes both an inner Bondi-type regime where gas pressure is balanced by the gravity of a central star and an outer Jeans-type regime where gas pressure is balanced by gas self-gravity. The gas density profile provided by this model makes a smooth transition from a wind-type inner solution to a Bonnor-Ebert-type outer solution. It is shown that high-velocity dust impinging on this cloud will tend to pile up due to having a different velocity profile from gas so that the dust-to-gas ratio is substantially enriched above the 1% interstellar medium (ISM) level.
I'm Moral, but I Won't Help You: The Distinct Roles of Empathy and Justice in Donations

Donating to charitable causes is generally perceived as a moral, prosocial behavior, but this may not always be the case. Although moral identity tends to have a positive effect on prosocial behavior, moral identity does not unconditionally enhance charitable giving. Four studies demonstrate that moral identity decreases donations when recipients are responsible for their plight. Mediation analysis reveals that empathy and justice underlie these effects such that moral identity increases donations for recipients with low plight responsibility through increased empathy, but moral identity decreases donations to recipients with high plight responsibility due to perceptions of justice. Importantly, donations to recipients who are responsible for their plight can be enhanced when donors� immorality is made salient, evoking empathy for recipients, particularly among donors with high moral identity. This research makes theoretical contributions in addition to providing implications for nonprofit organizations whose recipients may be perceived as responsible for their plight.
Improved error and work estimates for high-order elements

SUMMARY Work estimates for high-order elements are derived. The comparison of error and work estimates shows that even for relative accuracy in the 0.1% range, which is one order below the typical accuracy of engineering interest (1% range), linear elements may outperform all higher-order elements. As expected, the estimates also show that the optimal order of element in terms of work and storage demands depends on the desired relative accuracy. The comparison of work estimates for high-order elements and their finite difference counterparts reveals a work-ratio of several orders of magnitude. It thus becomes questionable if general geometric flexibility via micro-unstructured grids is worth such a high cost. Copyright © 2013 John Wiley & Sons, Ltd.
Decay of Solutions of Wave-type Pseudo-differential Equations over p-adic Fields

We show that the solutions of p–adic pseudo-differential equations of wave type have a decay similar to the solutions of classical generalized wave equations.
A flow-map model for analyzing pseudothresholds in fault-tolerant quantum computing

An arbitrarily reliable quantum computer can be efficiently constructed from noisy components using a recursive simulation procedure, provided that those components fail with probability less than the fault-tolerance threshold. Recent estimates of the threshold are near some experimentally achieved gate ?delities. However, the landscape of threshold estimates includes pseudothresholds, threshold estimates based on a subset of components and a low level of the recursion. In this paper, we observe that pseudothresholds are a generic phenomenon in fault-tolerant computation. We define pseudothresholds and present classical and quantum fault-tolerant circuits exhibiting pseudothresholds that differ by a factor of 4 from fault-tolerance thresholds for typical relationships between component failure rates. We develop tools for visualizing how reliability is influenced by recursive simulation in order to determine the asymptotic threshold. Finally, we conjecture that refinements of these methods may establish upper bounds on the fault-tolerance threshold for particular codes and noise models.
Causal inference in statistics: An overview

This review presents empiricalresearcherswith recent advances in causal inference, and stresses the paradigmatic shifts that must be un- dertaken in moving from traditionalstatistical analysis to causal analysis of multivariate data. Special emphasis is placed on the assumptions that un- derly all causal inferences, the languages used in formulating those assump- tions, the conditional nature of all causal and counterfactual claims, and the methods that have been developed for the assessment of such claims. These advances are illustrated using a general theory of causation based on the Structural Causal Model (SCM) described in Pearl (2000a), which subsumes and unifies other approaches to causation, and provides a coher- ent mathematical foundation for the analysis of causes and counterfactuals. In particular, the paper surveys the development of mathematical tools for inferring (from a combination of data and assumptions) answers to three types of causal queries: (1) queries about the effects of potential interven- tions, (also called "causal effects" or "policy evaluation") (2) queries about probabilities of counterfactuals, (including assessment of "regret," "attri- bution" or "causes of effects") and (3) queries about direct and indirect effects (also known as "mediation"). Finally, the paper defines the formal and conceptual relationships between the structural and potential-outcome frameworks and presents tools for a symbiotic analysis that uses the strong features of both.
The Casimir effect for conical pistons

In this paper we utilize ζ-function regularization techniques in order to compute the Casimir force for massless scalar fields subject to Dirichlet and Neumann boundary conditions in the setting of the conical piston. The piston geometry is obtained by dividing the bounded generalized cone into two regions separated by its cross section positioned at a with a ∈ (0, b) with b > 0. We obtain expressions for the Casimir force that are valid in any dimension for both Dirichlet and Neumann boundary conditions in terms of the spectral ζ-function of the piston. As a particular case, we specify the piston to be a d-dimensional sphere and present explicit results for d = 2, 3, 4, 5.
A practical approach to polar codes

In this paper, we study polar codes from a practical point of view. In particular, we study concatenated polar codes and rate-compatible polar codes. First, we propose a concatenation scheme including polar codes and Low-Density Parity-Check (LDPC) codes. We will show that our proposed scheme outperforms conventional concatenation schemes formed by LDPC and Reed-Solomon (RS) codes. We then study two rate-compatible coding schemes using polar codes. We will see that polar codes can be designed as universally capacity achieving rate-compatible codes over a set of physically degraded channels. We also study the effect of puncturing on polar codes to design rate-compatible codes.
Simplicity of noncommutative Dedekind domains

The following dichotomy is established: A finitely generated, complex Dedekind domain that is not commutative is a simple ring. Weaker versions of this dichotomy are proved for Dedekind prime rings and hereditary noetherian prime rings.
How well do we know the neutron structure function

We present a detailed analysis of the uncertainty in the neutron F{sub 2}n structure function extracted from inclusive deuteron and proton deep-inelastic scattering data. The analysis includes experimental uncertainties as well as uncertainties associated with the deuteron wave function, nuclear smearing, and nucleon off-shell corrections. Consistently accounting for the Q{sup 2} dependence of the data and calculations, and restricting the nuclear corrections to microscopic models of the deuteron, we find significantly smaller uncertainty in the extracted F{sub 2}n/F{sub 2}p ratio than in previous analyses. In addition to yielding an improved extraction of the neutron structure function, this analysis also provides an important baseline that will allow future, model-independent extractions of neutron structure to be used to examine nuclear medium effects in the the deuteron.
Cubical token systems

The paper deals with combinatorial and stochastic structures of cubical token systems. A cubical token system is an instance of a token system, which in turn is an instance of a transition system. A formal theory based on a system of four independent axioms for cubical token systems and main algebraic properties of these systems are introduced. A representation theorem for a cubical token system is established asserting that the graph of such a system is cubical. Stationary distributions for random walks on cubical token systems are calculated.
Capacity Bounds for Broadcast Channels With Confidential Messages

This paper studies capacity bounds for discrete memoryless broadcast channels with confidential messages. Two private messages as well as a common message are transmitted; the common message is to be decoded by both receivers, while each private message is only for its intended receiver. In addition, each private message is to be kept secret from the unintended receiver where secrecy is measured by equivocation. Both inner and outer bounds are proposed to the rate equivocation region for broadcast channels with confidential messages. The proposed inner bound generalizes Csiszar and Korner's rate equivocation region for broadcast channels with a single confidential message, Liu 's achievable rate region for broadcast channels with perfect secrecy, Marton's and Gel'fand-Pinsker's achievable rate region for general broadcast channels. The proposed outer bounds, together with the inner bound, help establish the rate equivocation region of several classes of discrete memoryless broadcast channels with confidential messages, including the less noisy, deterministic, and semideterministic broadcast channels. Furthermore, specializing to the general broadcast channel by removing the confidentiality constraint, the proposed outer bounds reduce to new capacity outer bounds for the discrete memory broadcast channel.
Bounds on expansion in LZ'77-like coding

We investigate the maximum increase in number of phrases that results from changing k consecutive symbols in a string x having length n parsed using an LZ'77-like algorithm. We consider a class of compression algorithms that partition a sequence into a collection y of nonoverlapping, variable-length phrases and encode them. Each phrase either is a singleton or matches a substring that starts to its left. We show that changing a single symbol of x in position i can yield an expansion that is of order O(n-i)/sup 2/3/ as (n-i)/spl rarr//spl infin/. Our lower bound requires an alphabet size of O(n-i)/sup 1/3/. We also show that changing k consecutive symbols starting from position i can yield an expansion having a similar but somewhat more involved form. The paper contains both analytically derived upper and lower bounds, and algorithms for numerically computing tighter bounds. While deriving the bounds, we provide a detailed analysis of how expansion can arise when changing consecutive symbols. This problem is motivated by management policies for computer systems, such as the IBM Memory eXpansion Technology (MXT) or the IBM iSeries compressed disks, that use LZ'77-like coding on small compression units, such as 1-4 kbyte, and store the compressed data in memory or on disk tracks. Here, when a change of a portion of the compression unit occurs, for example, an L2 cache line, or a 512-byte disk sector, the data is recompressed and potentially stored in a different location. Knowing the maximum expansion, rather than the average expansion, is an important factor for designing policies for allocation and management of memory or disk space.
Analyzing the Anglo-American Hegemony in the Times Higher Education Rankings

This study analyzes the 2009 Times Higher Education-QS top 200 universities in the world. Based on this analysis the study claims that the THS reflects the phenomenon of Anglo-American hegemony. The United States with 54 universities and the United Kingdom with 29 dominated the THS. In addition, six out of every ten universities on the top 200 list were located in countries that were at one time partly or fully colonized by the United Kingdom. This study identifies a number of factors that contributed to a country having at least one university ranked on the list: Age of an institution, endowment of an institution, the size of a nation's population, gross domestic products (GDP) and GDP per capita, level of international trade (exports/imports), colonial heritage and language.
The OAI data-provider registration and validation service

I present a summary of recent use of the Open Archives Initiative (OAI) registration and validation services for data-providers. The registration service has seen a steady stream of registrations since its launch in 2002, and there are now over 220 registered repositories. I examine the validation logs to produce a breakdown of reasons why repositories fail validation. This breakdown highlights some common problems and will be used to guide work to improve the validation service.
Serum and MRI biomarkers in mobile device texting: a pilot study.

Objective: We aimed to determine if serum biochemical and MRI biomarkers differed between high volume (≥ 230 texts sent/day; n = 5) and low volume (≤ 25 texts sent/day; n = 5) texters. A secondary ...
A MODIFIED FORM OF THE TRUE‐FALSE TEST

Ever since McCall1 first formally introduced the true-false test, many articles in educational magazines, as well as chapters in pedagogical books, have been devoted to this popular "new type" test. Moreover, a careful examination of the complete bibliography of such testing, prepared by Brinkley,2 reveals that most of the contributions bearing upon the true-false test either describe the test, analyze its merits and shortcomings, or discuss the statistical considerations relative to the guessing factor as it affects the scoring. To date few attempts to modify the form of the true-false test so as to eliminate objections which are generally recognized as inherent in its present form have been recorded ; but expressions of a desire for its improvement are not infrequently found. Barthelmess, for example, points out the weakness of the true-false "as an instrument for diagnosing special individual difficulties," and says further, "if a test could be devised which would have all the advantages of the true-false and correct for this disadvantage, it would be heartily wel comed."3 A few modifications of the test, however, have been sug gested. Knight requires his students to mark the test questions "T," "F," and "U" (undecided) and gives them time only to read each statement and make an instantaneous decision. An ad vantage of this modification, he thinks, is that it "discourages the proclivity to borrow from one's neighbors."4 Farwell gives
Automatic Mapping of Social Networks of Actors from Text Corpora: Time Series Analysis

To illustrate the WORDij approach to automatic social network identification from large volumes of text, this research mined the social networks among President Clinton’s cabinet members (n=24) and also President G.W. Bush’s cabinet members (n=45) over each of their two terms based on the members co-occurrence in news stories. The software used a time-slice interval of 30 days for Clinton stories because the average days between Gallup presidential job approval poll ratings was 30 days, resulting in 97 time slices. For Bush the average number of days between polls was 22 days, resulting in a 132-point time series. This synchronized the social networks with presidential job approval ratings. Clinton and Bush had nearly opposite relationships between network centrality and job approval. Automatic network analysis of social actors from textual corpora is feasible and enables testing hypotheses over time.
Quantitative analysis of the implementation of economic plans in Latin America

Abstract In this paper an index of plan implementation is defined and applied to the 1960–1970 educational plans of Latin American countries. Statistical analysis is used to specify the determinants of the values of the index. It is shown that a lack of statistical data and of qualified personnel are the main reasons for insufficient plan implementation.
Mixing Times for Markov Chains on Wreath Products and Related Homogeneous Spaces

We develop a method for analyzing the mixing times for a quite general class of Markov chains on the complete monomial group $G \wr S_n$ and a quite general class of Markov chains on the homogeneous space $(G\wr S_n) / (S_r\times S_{n-r})$. We derive an exact formula for the $L^2$ distance in terms of the $L^2$ distances to uniformity for closely related random walks on the symmetric groups $S_j$ for $1 \leq j \leq n$ or for closely related Markov chains on the homogeneous spaces $S_{i+j}/ (S_i~\times~S_j)$ for various values of $i$ and $j$, respectively. Our results are consistent with those previously known, but our method is considerably simpler and more general.
Codex-dp: co-design of communicating systems using dynamic programming

We present a novel algorithm based on dynamic programming with binning to find, subject to a given deadline, the minimum-cost coarse-grain hardware/software partitioning and mapping of communicating processes in a generalized task graph. The task graph includes computational processes which communicate with each other by means of blocking/nonblocking communication mechanisms at times including, but also other than, the beginning or end of their lifetime. The proposed algorithm has been implemented and experimental results are reported.
Laser Spectroscopy of UO: Characterization and Assignment of States in the 0- to 3-eV Range, with a Comparison to the Electronic Structure of ThO

Abstract Wavelength-resolved fluorescence excitation techniques have been used to record 33 electronic transitions of UO at a resolution of 0.03 cm-1. Nine low-lying electronic states that correlated with either U2+(5f37s)O2− or U2+(5f27s2)O2− were characterized. With few exceptions, Ω assignments were unambiguously determined from observations of the first lines in at least two rotational branches. Accurate term energies and rotational constants are reported. Deperturbed constants of ωe = 846.5 cm−1 and Re = 1.8383 A have been determined for the ground state of the 5f37s configuration, and ωe = 934.9 cm−1 and Re = 1.7932 A for states of the 5f27s2 configuration. Ligand field theory models were used to analyze the low-energy electronic structure of UO. Fitted values of the ligand field parameters B20(5f) = 6488, B40(5f) = 742, and B60(5f) = 118 cm−1 did not agree with values calculated using a relativistic Dirac-Fock formalism B20(5f) = 26 130, B40(5f) = 12 130, and B60(5f) = 12 020 cm−1). Ligand field theory calculations were also used in an attempt to provide configurational assignments for the excited states of UO and ThO. Experimentally derived values for ΔB00(nl/n′l′) parameters were used to predict the electronic structures of UO and UO′. The energies of 23 electronic configurations of UO, and 19 electronic configurations of UO+, have been calculated. The density distributions of the bound states of UO and UO+ up to their ionization limits were also calculated.
The inverse electron demand Diels-Alder click reaction in radiochemistry.

The inverse electron-demand Diels-Alder (IEDDA) cycloaddition between 1,2,4,5-tetrazines and strained alkene dienophiles is an emergent variety of catalyst-free ‘click’ chemistry that has the potential to have a transformational impact on the synthesis and development of radiopharmaceuticals. The ligation is selective, rapid, high-yielding, clean, and bioorthogonal and, since its advent in 2008, has been employed in a wide variety of chemical settings. In radiochemistry, the reaction has proven particularly useful with 18F and has already been utilized to create a number of 18F-labeled agents, including the PARP1-targeting small molecule 18F-AZD2281, the αvβ3 integrin-targeting peptide 18F-RGD, and the GLP-1-targeting peptide 18F-exendin. The inherent flexibility of the ligation has also been applied to the construction of radiometal-based probes, specifically the development of a modular strategy for the synthesis of radioimmunoconjugates that effectively eliminates variability in the construction of these agents. Further, the exceptional speed and biorthogonality of the reaction have made it especially promising in the realm of in vivo pretargeted imaging and therapy, and pretargeted imaging strategies based on the isotopes 111In, 18F, and 64Cu have already proven capable of producing images with high tumor contrast and low levels of uptake in background, nontarget organs. Ultimately, the characteristics of inverse electron-demand Diels–Alder click chemistry make it almost uniquely well-suited for radiochemistry, and although the field is young, this ligation has the potential to make a tremendous impact on the synthesis, development, and study of novel radiopharmaceuticals.
Stochastic Maximum-Likelihood DOA Estimation in the Presence of Unknown Nonuniform Noise

This correspondence investigates the direction-of-arrival (DOA) estimation of multiple narrowband sources in the presence of nonuniform white noise with an arbitrary diagonal covariance matrix. While both the deterministic and stochastic Cramer-Rao bound (CRB) and the deterministic maximum-likelihood (ML) DOA estimator under this model have been derived by Pesavento and Gershman, the stochastic ML DOA estimator under the same setting is still not available in the literature. In this correspondence, a new stochastic ML DOA estimator is derived. Its implementation is based on an iterative procedure which concentrates the log-likelihood function with respect to the signal and noise nuisance parameters in a stepwise fashion. A modified inverse iteration algorithm is also presented for the estimation of the noise parameters. Simulation results have shown that the proposed algorithm is able to provide significant performance improvement over the conventional uniform ML estimator in nonuniform noise environments and require only a few iterations to converge to the nonuniform stochastic CRB.
The SIR-C/X-SAR Synthetic Aperture Radar system

The Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) was a joint United States/German/Italian space agency imaging radar system successfully flown aboard the shuttle Endeavor in April 1994 and again in September/October 1994. The multifaceted SIR-C/X-SAR represents a major technological step forward in radar remote sensing and is the first spaceborne multifrequency, polarimetric SAR. The United States developed SIR-C operated at L- and C-band, each with quad polarization. The SIR-C antenna was an active phased array, with the capability for electronic beam steering and multiple swath width illumination. The German/Italian X-SAR operated at X-band with a single polarization using a slotted waveguide antenna, mechanically steerable in elevation. SIR-C and X-SAR were designed to operate synchronously, collecting data over common sites synchronously. A total of 143 hours (93 terabits) of SAR data were recorded on tape. >
Relativistic dynamics of accelerating particles derived from field equations

In relativistic mechanics the energy-momentum of a free point mass moving without acceleration forms a four-vector. Einstein’s celebrated energy-mass relation E=mc2 is commonly derived from that fact. By contrast, in Newtonian mechanics the mass is introduced for an accelerated motion as a measure of inertia. In this paper we rigorously derive the relativistic point mechanics and Einstein’s energy-mass relation using our recently introduced neoclassical field theory where a charge is not a point but a distribution. We show that both the approaches to the definition of mass are complementary within the framework of our field theory. This theory also predicts a small difference between the electron rest mass relevant to the Penning trap experiments and its mass relevant to spectroscopic measurements.
A model for hydrogen-induced piezoelectric effect in InP HEMTs and GaAs PHEMTs

We have developed a model for the impact of the hydrogen-induced piezoelectric effect on the threshold voltage of InP HEMTs and GaAs PHEMTs. We have used two-dimensional (2-D) finite element simulations to calculate the mechanical stress caused by a Ti-containing metal gate that has expanded due to hydrogen absorption. This has allowed us to map the 2-D piezoelectric charge distribution in the semiconductor heterostructure. We then used a simple electrostatics model to calculate the impact of this piezoelectric polarization charge on the threshold voltage. The model explains experimental observations of hydrogen-induced threshold voltage shifts, both in InP HEMTS and in GaAs PHEMTs. It also suggests ways to mitigate the hydrogen sensitivity of these devices.
CONSERVATION LARYNGEAL SURGERY VERSUS TOTAL LARYNGECTOMY FOR RADIATION FAILURE IN LARYNGEAL CANCER

Background. Total laryngectomy is the standard of care for surgical salvage of radiation failure in laryngeal cancer. However, the role of conservation laryngeal surgery in this set- ting remains unclear. The objective was to compare the efficacy of conservation versus total laryngectomy for salvage of radia- tion failure in patients who initially presented with T1 or T2 squa- mous cancer of the larynx. Methods. A 21-year retrospective analysis of patients who received surgery at a single comprehensive cancer center after definitive radiation therapy is reported. At recurrence, the pa- tients were reevaluated and then underwent a total laryngectomy or, if possible, a conservation laryngeal procedure. The charts of 105 patients who failed radiation treatment for primary laryngeal cancer and who subsequently underwent surgical salvage were reviewed for this study. Eighty-nine were male (84.8%). The mean age was 60.3 years. The median follow-up time after sur- gery was 69.4 months. Most patients with recurrence after radio- therapy required total laryngectomy (69.5%; 73/105). Conserva- tion laryngeal surgery was performed for 32 patients (31.5%). Concomitant neck dissections were performed on 45 patients (45.5%). Results. In 14 patients, local or regional recurrence devel- oped after salvage surgery: 9 patients after total laryngectomy (12.3%; 9/73), and 5 patients (15.6%; 5/32) after conservation la- ryngeal surgery. This difference was not statistically significant, nor was there a difference in disease-free interval for the two procedures (p ¼ .634, by log-rank test). Distant metastasis developed in 13 patients. Most developed in the setting of local and/or regional recurrence, but distant metastasis occurred as the only site of failure in 6 of the patients who had undergone total laryngectomy but in 1 of the conservation surgery patients treated for a supraglottic laryngeal cancer. The overall mortality for patients who underwent total laryngectomy was also higher: 73.74% (54/73) versus 59.4% (19/32) for patients who under- went a conservation approach (p ¼ .011 by log-rank test). Conclusions. Although conservation laryngeal surgery was possible in a few patients with local failure after radiotherapy, conservation laryngeal surgery is an oncologically sound alter- native to total laryngectomy for these patients. V C 2006 Wiley
Novel sorting network-based architectures for rank order filters

This paper presents two novel sorting network-based architectures for computing high sample rate nonrecursive rank order filters. The proposed architectures consist of significantly fewer comparators than existing sorting network-based architectures that are based on bubble-sort and Batcher's odd-even merge sort. The reduction in the number of comparators is obtained by sorting the columns of the window only once, and by merging the sorted columns in a way such that the number of candidate elements for the output is very small. The number of comparators per output is reduced even further by processing a block of outputs at a time. Block processing procedures that exploit the computational overlap between consecutive windows are developed for both the proposed networks. >
Doubly Salient Permanent-Magnet Machine With Skewed Rotor and Six-State Commutating Mode

We propose new concepts for the design, optimization, and control of a doubly salient permanent-magnet machine (DSPM). We employ a uniform pole width so that the width of the rotor pole is the same as that of the stator salient pole. This design aims to minimize the cogging torque. Second, we used a skewed rotor with one-half the pole width to improve the commutation. Finally, based on the flux linkage of the skewed rotor, we used a six-state commutating mode to control the motor. We validated the feasibility of these new design concepts by simulations, field analysis, and experimental measurements of the prototype.
Pharmaceutical regulation and innovative performance: a decision-theoretic model

In this paper we develop a model of the impact of the drug approval process on the terms of a contract between a pharmaceutical company that requires the services of a contract research organization (CRO) to carry out testing of new drug molecules. Results show that if the equilibrium contract includes a variable payment (royalty), the CRO gives more eort to create a more accurate result, the more strict the FDA approval process. We also …nd that given the royalty shares in the contract if the FDA demands more accuracy in results as a condition of approval, then the CRO will generate more accurate results from late stage tests. However, greater FDA stringency in the approval process bene…ts pharmaceutical companies because the greater is FDA stringency, the less is the risk of a drug recall. We also …nd that in order to employ a CRO in the testing process, the pharmaceutical company's prior probability that the drug is of high quality must be very high. JEL categories: L24, L65
The eukaryotic initiation factor 2 kinase GCN2 protects against hepatotoxicity during asparaginase treatment.

Asparaginase is an important drug in the treatment regimen for acute lymphoblastic leukemia. Asparaginase depletes circulating asparagine and glutamine, activating an amino acid stress response (AA...
MEASURING THE CONTRIBUTIONS OF KNOWLEDGE MANAGEMENT SYSTEMS TO THE STRATEGIC COMPETITIVENESS OF ORGANIZATIONS: A REVIEW AND A MODEL

Why and how do Knowledge Management Systems (KMS) contribute to the strategic competitiveness of organizations? This paper reviews the literature and proposes a model in which KMS is viewed from three different perspectives: (1) crucial resource; (2) driver of absorptive capacity; and (3) innovation adopted by the organization. The paper critiques the method used by KMS researchers whereby co-variation of KMS and competitiveness is utilized to study the relationship between these variables. The model proposed here is a multi-stage process. The successful use of KMS generates intermediate outcomes that in turn impact the organization and produces improved strategic competitiveness. The different approaches to KMS and the stage-process allow for the unique attributes of knowledge systems, different from information systems. The advantages and limitations of the model are discussed.
CONSEQUENCES OF MODELING HABIT PERSISTENCE

In this paper, we study the stationary and non-stationary equilibria of a deterministic, pure exchange, two-period overlapping generations model with habit persistence. We show that preferences with multiplicative habits can lead to quite different equilibrium outcomes compared to subtractive ones. The two most commonly adopted habit specifications can differ in terms of homotheticity, gross substitutability, and uniqueness of equilibria. We illustrate these differences in terms of steady-state equilibria, as well as local dynamics.
Practical aerobic oxidations of alcohols and amines with homogeneous copper/TEMPO and related catalyst systems.

Alcohol and amine oxidations are common reactions in laboratory and industrial synthesis of organic molecules. Aerobic oxidation methods have long been sought for these transformations, but few practical methods exist that offer advantages over traditional oxidation methods. Recently developed homogeneous Cu/TEMPO (TEMPO = 2,2,6,6-tetramethylpiperidinyl-N-oxyl) and related catalyst systems appear to fill this void. The reactions exhibit high levels of chemoselectivity and broad functional-group tolerance, and they often operate efficiently at room temperature with ambient air as the oxidant. These advances, together with their historical context and recent applications, are highlighted in this minireview.
Technology mapping for SOI domino logic incorporating solutions for the parasitic bipolar effect

We present a technology mapping algorithm for implementing a random logic gate network in domino logic. The target technology of implementation is silicon-on-insulator (SOI). SOI devices exhibit an effect known as parasitic bipolar effect (PBE), which can lead to incorrect logic values in the circuit. Our algorithm solves the technology mapping problem by permitting several transformations during the mapping process in order to avoid PBE, such as transistor reordering, altering the way that transistors are organized into gates, and adding pMOS discharge transistors. We minimize the total cost of implementation, which includes discharge transistors required for correct functioning. Our algorithm generates solutions that reduce the number of discharge transistors required by 53% and reduces the size of the final solution by 6.3% on average. We compare our results with a modification of a current technology mapping algorithm for bulk CMOS domino logic that reduces the cost of the final solution and find that our algorithm outperforms this method.
A Polymer‐Supported Phosphoramide as a Lewis‐Base Catalyst for the Catalytic Aldol Reaction

The aldol reactions between trichlorosilyl enol ethers and aldehydes were catalyzed by an environmentally benign polymer-supported phosphoramide organocatalyst. Eight examples are reported with moderate to good chemical yields and stereoselectivity. Significant rate enhancements were observed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Experimental realization of Shor's quantum factoring algorithm using nuclear magnetic resonance

The number of steps any classical computer requires in order to find the prime factors of an l-digit integer N increases exponentially with l, at least using algorithms known at present. Factoring large integers is therefore conjectured to be intractable classically, an observation underlying the security of widely used cryptographic codes. Quantum computers, however, could factor integers in only polynomial time, using Shor's quantum factoring algorithm. Although important for the study of quantum computers, experimental demonstration of this algorithm has proved elusive. Here we report an implementation of the simplest instance of Shor's algorithm: factorization of N = 15 (whose prime factors are 3 and 5). We use seven spin-1/2 nuclei in a molecule as quantum bits, which can be manipulated with room temperature liquid-state nuclear magnetic resonance techniques. This method of using nuclei to store quantum information is in principle scalable to systems containing many quantum bits, but such scalability is not implied by the present work. The significance of our work lies in the demonstration of experimental and theoretical techniques for precise control and modelling of complex quantum computers. In particular, we present a simple, parameter-free but predictive model of decoherence effects in our system.
Blending Online Asynchronous and Synchronous Learning.

In this article I will share a qualitative self-study about a 15-week blended 100% online graduate level course facilitated through synchronous meetings on Blackboard Collaborate and asynchronous discussions on Blackboard. I taught the course at the University of Tennessee (UT) during the spring 2012 semester and the course topic was online learning environments. The primary research question of this study was: How can the designer/instructor optimize learning experiences for students who are studying about online learning environments in a blended online course relying on both synchronous and asynchronous technologies? I relied on student reflections of course activities during the beginning, middle, and the end of the semester as the primary data source to obtain their insights regarding course experiences. Through the experiences involved in designing and teaching the course and engaging in this study I found that there is room in the instructional technology research community to address strategies for facilitating online synchronous learning that complement asynchronous learning. Synchronous online whole class meetings and well-structured small group meetings can help students feel a stronger sense of connection to their peers and instructor and stay engaged with course activities. In order to provide meaningful learning spaces in synchronous learning environments, the instructor/designer needs to balance the tension between embracing the flexibility that the online space affords to users and designing deliberate structures that will help them take advantage of the flexible space.