cssi/SciSciGPT-SciSciNet huggingface dataset:
Bcl-2 Family Genetic Profiling Reveals Microenvironment-Specific Determinants of Chemotherapeutic Response

The Bcl-2 family encompasses a diverse set of apoptotic regulators that are dynamically activated in response various cell intrinsic and extrinsic stimuli. An extensive variety of cell culture experiments have identified effects of growth factors, cytokines and drugs on BCL-2 family functions, but in vivo studies have tended to focus on role of one or two particular members in development and organ homeostasis. Thus, the ability of physiologically relevant contexts to modulate canonical dependencies that are likely to be more complex has yet to be investigated systematically. In this study, we report findings derived from a pool-based shRNA assay that systematically and comprehensively interrogated the functional dependence of leukemia and lymphoma cells upon various BCL-2 family members across many diverse in vitro and in vivo settings. This approach permitted us to report the first in vivo loss of function screen for modifiers of the response to a frontline chemotherapeutic agent. Notably, our results reveal an unexpected role for the extrinsic death pathway as a tissue-specific modifier of therapeutic response. In particular, our findings demonstrate that particular tissue sites of tumor dissemination play critical roles in demarcating the nature and extent of cancer cell vulnerabilities and mechanisms of chemoresistance.
An Investigation of Diffuse Interstellar Gas toward a Large, Low-Extinction Window into the Inner Galaxy

H? and H? spectroscopy with the Wisconsin H? Mapper (WHAM) reveals a strong concentration of high-velocity emission in a ?5? ? 5? area centered near (l, b) = (27?, - 3?), known as the Scutum cloud. The high velocities imply that we are detecting optical emission from near the plane of the Galaxy out to the tangent point at heliocentric distances of D? 6 kpc, assuming that the gas participates in circular Galactic rotation. The ratio of the H? to H? emission as a function of velocity suggests that dust along these lines of sight produces a total visual extinction of AV ? 3 at D? ~ 6 kpc. This makes it possible to use optical emission lines to explore the physical conditions of ionized gas in the inner Galaxy. At a Galactocentric distance RG ? 4 kpc, for example, we find that the H+ has an rms midplane density of ?1 cm-3 with a vertical scale height of ?300 pc. We also find evidence for an increase in the flux of Lyman continuum photons and an increase in the ratio of ionized to neutral hydrogen toward the inner Galaxy. We have extended the measurements of E(B - V) in this direction to distances far beyond what has been accessible through stellar photometry and find E(B - V)/NH to be near the local mean of 1.7 ? 10-22 cm2 mag, with evidence for an increase in this ratio at RG ? 4 kpc. Finally, our observations of [N II]??6583, [S II]??6716, and [O III]??5007 toward the window reveal that in the inner Galaxy the temperature of the gas and the ionization state of oxygen increase with increasing height from the midplane.
Plane Curves with Prescribed Triple Points: A Toric Approach

We will use toric degenerations of the projective plane ℙ2 to give a new proof of the triple points interpolation problems in the projective plane. We also give a complete list of toric surfaces that are useful as components in this degeneration.
Highly Diastereoselective Preparation of anti-1,2-Diols by Catalytic Addition of Alkynylsilanes to α-Silyloxyaldehydes

The catalytic, diastereoselective coupling of α-silyloxy aldehydes and alkynylsilanes catalyzed by a nickel(0) N-heterocyclic carbene complex provides an effective entry to anti-1,2-diols. The scope of couplings and extent of diastereoselection are excellent across a range of substrates.
Numerical modeling of endogenic thermal anomalies on Europa

Abstract A variety of recent resurfacing features have been observed on Europa, which may produce thermal anomalies detectable by a future mission. However, the likelihood of such a detection depends on their size and lifetimes. The results of this numerical study suggest that the lifetime of a thermal anomaly associated with the emplacement of 100 m of water onto the surface of Europa is several hundred years, and ∼10 years for 10 m of water. If warm ice is emplaced on the surface instead of liquid water, these lifetimes decrease by up to a factor of two. Exploration of model parameters indicates that a thin insulating surface layer can double thermal anomaly lifetimes, anomalies emplaced at a latitude of 80° can remain detectable nearly a factor of two longer than those at equatorial latitudes, and anomalies on the night side can remain detectable for up to ∼20% longer than those on the day side. High temperatures are very short-lived as the surface ice cools very rapidly to below 200 K due to sublimation cooling. Assuming steady-state resurfacing, the number of detectable thermal anomalies associated with the emplacement of 100 m of water would be on the order of 10 if the typical resurfacing area is 15 km 2 . If recent resurfacing is dominated by chaos regions with typical areas of 100 to 1000 km 2 and lifetimes of 1000 to 4000 years, the number of detectable thermal anomalies would be on the order of 1 to 10.
Expressing ethnicity through behaviors of a robot character

Achieving homophily, or association based on similarity, between a human user and a robot holds a promise of improved perception and task performance. However, no previous studies that address homophily via ethnic similarity with robots exist. In this paper, we discuss the difficulties of evoking ethnic cues in a robot, as opposed to a virtual agent, and an approach to overcome those difficulties based on using ethnically salient behaviors. We outline our methodology for selecting and evaluating such behaviors, and culminate with a study that evaluates our hypotheses of the possibility of ethnic attribution of a robot character through verbal and nonverbal behaviors and of achieving the homophily effect.
B physics with the CDF Run II upgrade

During the Run 1 data taking period, from 1992 through 1995, CDF has acquired 110 pb{sup {minus}1} of p{anti p} collisions at a center of mass energy of 1,800 GeV. This data has provided many results on B physics, and provides a basis for extrapolating to Run 2, which is scheduled to start in 1999 after major upgrades to both the accelerator and detector. The authors present herein a summary of Run 1 results relevant to an analysis of the CP asymmetry in B {yields} J/{psi}K{sub s}, the CDF upgrade plans for Run 2, and some of the main B physics goals related to the exploration of the origin of CP violation.
Operator based multiscale method for compressible flow

Multiscale methods have been developed for accurate and efficient numerical solution of flow problems in large-scale heterogeneous reservoirs. A scalable and extendible Operator Based Multiscale Method (OBMM) is described here. OBMM is cast as a general algebraic framework. It is natural and convenient to incorporate more physics in OBMM for multiscale computation. In OBMM, two operators are constructed: prolongation and restriction. The prolongation operator is constructed by assembling the multiscale basis functions. The specific form of the restriction operator depends on the coarse-scale discretization formulation (e.g., finitevolume or finite-element). The coarse-scale pressure equation is obtained algebraically by applying the prolongation and restriction operators to the fine-scale flow equations. Solving the coarse-scale equation results in a high quality coarse-scale pressure. The fine scale pressure can be reconstructed by applying the prolongation operator to the coarse-scale pressure. A conservative fine-scale velocity field is then reconstructed to solve the transport (saturation) equation. We describe the OBMM approach for multiscale modeling of compressible multiphase flow. We show that extension from incompressible to compressible flows is straightforward. No special treatment for compressibility is required. The efficiency of multiscale formulations over standard fine-scale methods is retained by OBMM. The accuracy of OBMM is demonstrated using several numerical examples including a challenging depletion problem in a strongly heterogeneous permeability field (SPE 10).
Accounting for Experimental Noise Reveals That mRNA Levels, Amplified by Post-Transcriptional Processes, Largely Determine Steady-State Protein Levels in Yeast

Cells respond to their environment by modulating protein levels through mRNA transcription and post-transcriptional control. Modest observed correlations between global steady-state mRNA and protein measurements have been interpreted as evidence that mRNA levels determine roughly 40% of the variation in protein levels, indicating dominant post-transcriptional effects. However, the techniques underlying these conclusions, such as correlation and regression, yield biased results when data are noisy, missing systematically, and collinear---properties of mRNA and protein measurements---which motivated us to revisit this subject. Noise-robust analyses of 24 studies of budding yeast reveal that mRNA levels explain more than 85% of the variation in steady-state protein levels. Protein levels are not proportional to mRNA levels, but rise much more rapidly. Regulation of translation suffices to explain this nonlinear effect, revealing post-transcriptional amplification of, rather than competition with, transcriptional signals. These results substantially revise widely credited models of protein-level regulation, and introduce multiple noise-aware approaches essential for proper analysis of many biological phenomena.
Coupled external cavity photonic crystal enhanced fluorescence

We report a fundamentally new approach to enhance fluorescence in which surface adsorbed fluorophore-tagged biomolecules are excited on a photonic crystal surface that functions as a narrow bandwidth and tunable mirror of an external cavity laser. This scheme leads to ∼10× increase in the electromagnetic enhancement factor compared to ordinary photonic crystal enhanced fluorescence. In our experiments, the cavity automatically tunes its lasing wavelength to the resonance wavelength of the photonic crystal, ensuring optimal on-resonance coupling even in the presence of variable device parameters and variations in the density of surface-adsorbed capture molecules. We achieve ∼105× improvement in the limit of detection of a fluorophore-tagged protein compared to its detection on an unpatterned glass substrate. The enhanced fluorescence signal and easy optical alignment make cavity-coupled photonic crystals a viable approach for further reducing detection limits of optically-excited light emitters that are used in biological assays. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
An enantioselective total synthesis of phomopsolide C

A flexible enantioselective route to highly functionalized α,β-unsaturated δ-lactones, has allowed for the synthesis of phomopsolide C. This approach derives its asymmetry from (S)-lactic acid and by applying the Sharpless catalytic asymmetric dihydroxylation to vinylfuran. The resulting diols are produced in high enantioexcess and can be stereoselectively transformed into α,β-unsaturated-δ-lactones via a short highly diastereoselective oxidation and reduction sequence. A Wittig olefination reaction was used to introduce the side chain in either cis or trans form that was further elaborated into phomopsolide C.
Consumer and relationship factors associated with shared decision making in mental health consultations.

Objective:This study explored the association between shared decision making and consumers’ illness management skills and consumer-provider relationships.Methods:Medication management appointments for 79 consumers were audio recorded. Independent coders rated overall shared decision making, minimum level of shared decision making, and consumer-provider agreement for 63 clients whose visit included a treatment decision. Mental health diagnoses, medication adherence, patient activation, illness management, working alliance, and length of consumer-provider relationships were also assessed. Correlation analyses were used to determine relationships among measures.Results:Overall shared decision making was not associated with any variables. Minimum levels of shared decision making were associated with higher scores on the bond subscale of the Working Alliance Inventory, indicating a higher degree of liking and trust, and with better medication adherence. Agreement was associated with shorter consumer-provider r...
Cluster Trees on Manifolds

In this paper we investigate the problem of estimating the cluster tree for a density f supported on or near a smooth d-dimensional manifold M isometrically embedded in ℝD. We analyze a modified version of a k-nearest neighbor based algorithm recently proposed by Chaudhuri and Dasgupta (2010). The main results of this paper show that under mild assumptions on f and M, we obtain rates of convergence that depend on d only but not on the ambient dimension D. Finally, we sketch a construction of a sample complexity lower bound instance for a natural class of manifold oblivious clustering algorithms.
Match-Point Solutions for Robust Flutter Analysis

The computation of robust e utter speeds presents a signie cant advancement over traditional types of e utter analysis. In particular, π-method analysis is able to generate robust e utter speeds that represent worst-case e ight conditions with respect to potential modeling errors. Robust e utter speeds may be computed using a model formulation that has been previously presented; however, that formulation has limitations in its ability to generate a match-point solution. A model formulation is introduced for which π-method analysis is guaranteed to compute a match-point solution. The match-point solution is immediately realized by analyzing a single model so the computation time is reduced from the previous approach that required iterations. Also, the solution is able to consider parametric uncertainty in any element, whereas the previous formulation did not consider mass uncertainty. The match-point formulation is derived by properly treating the nonlinear perturbations and uncertainties that affect theequation of motion. TheAerostructures Test Wing isused to demonstrate thatthe π-method analysis computes match-point e utter speeds using this new formulation.
Low-Mass Stars and Substellar Objects in the NGC 1333 Molecular Cloud

We present the results of near-infrared imaging and low-resolution near-infrared spectroscopy of low-mass objects in the NGC 1333 molecular cloud. A JHK survey of an 114 × 117 area of the northern cluster was conducted to a sensitivity of K ≤ 16 mag. Using near-infrared magnitudes and colors from this and previously published surveys, 25 brown dwarf candidates were selected toward the high-extinction cloud core. Spectra in the K band were obtained and comparisons of the depths of water vapor absorption bands in our candidate objects with a grid of dwarf, subgiant, and giant standards were made to derive spectral types. These data were then used to derive effective temperatures and stellar luminosities that, when combined with theoretical tracks and isochrones for pre–main-sequence objects, resulted in estimates for their masses and ages. The models suggest a median age for the sample of less than 1 Myr with substellar masses for at least nine of the candidates, including the X-ray flare source ASR 24. Surface gravities have been estimated for the brown dwarf candidates and, for a given spectral type, are found to more closely resemble dwarfs than giants. Using the near-infrared imaging data and age estimates from the spectroscopic sample, an extinction-limited sample in the northern cluster was defined. Consistent with recent studies of other young clusters, this sample exhibits an accretion disk frequency of 0.75 ± 0.20 and a mass spectrum slope across the hydrogen-burning limit of α ≤ 1.6, where dN/dM ∝ M-α.
Secure communication in the low-SNR regime: A Characterization of the energy-secrecy tradeoff

Secrecy capacity of a multiple-antenna wiretap channel is studied in the low signal-to-noise ratio (SNR) regime. Expressions for the first and second derivatives of the secrecy capacity with respect to SNR at SNR = 0 are derived. Transmission strategies required to achieve these derivatives are identified. In particular, it is shown that it is optimal in the low-SNR regime to transmit in the maximum-eigenvalue eigenspace of Φ = H m † H m − N m /N e H e † H e where H m and H e denote the channel matrices associated with the legitimate receiver and eavesdropper, respectively, and N m and N e are the noise variances at the receiver and eavesdropper, respectively. Energy efficiency is analyzed by finding the minimum bit energy required for secure and reliable communications, and the wideband slope. Increased bit energy requirements under secrecy constraints are quantified. Finally, the impact of fading is investigated.
Spin-flip equation-of-motion coupled-cluster electronic structure method for a description of excited states, bond breaking, diradicals, and triradicals.

The spin-flip (SF) approach to multireference situations (e.g., bond breaking, diradicals, and triradicals) is described. Both closed- and open-shell low-spin states are described within a single reference formalism as spin-flipping, e.g., α → β, excitations from a high-spin reference state for which both dynamical and nondynamical correlation effects are much smaller than for the corresponding low-spin state. Formally, the SF approach can be viewed as an equation-of-motion model, where target states are sought on the basis of determinants conserving the total number of electrons but changing the number of α and β electrons.
Synthesis of the apoptosis inducing agent apoptolidin. Assembly of the C(16)-C(28) fragment.

A stereoselective synthesis of the C(16)−C(28) fragment of the apoptosis inducing agent apoptolidin is described. Key steps include two propionate aldol reactions and a stereoselective Mukaiyama aldol addition of enolsilane 19 to β-methoxy aldehyde 4.
Vortex Induced Vibration and Frequency Lock-in of an Airfoil at High Angles of Attack

Vortex-induced vibration is a fluid instability where vortices due to secondary flows exert a periodic unsteady force on the elastic structure. Under certain circumstances, the shedding frequency can lock into the structure natural frequency and lead to limit cycle oscillations. These vibrations may cause material fatigue and are a common source of structural failure. This work uses a frequency domain, harmonic balance (HB) computational fluid dynamics (CFD) code to predict the natural shedding frequency and lock-in region of an airfoil at very high angles of attack. The numerical results are then successfully compared to experimental data from wind tunnel testings.
A higher-dimensional model of the nucleon–nucleon central potential

Based on a theory of extra dimensional confinement of quantum particles [E. R. Hedin, Physics Essays, 2012, 25(2): 177], a simple model of a nucleon-nucleon (NN) central potential is derived which quantitatively reproduces the radial profile of other models, without adjusting any free parameters. It is postulated that a higher-dimensional simple harmonic oscillator confining potential localizes particles into three-dimensional (3D) space, but allows for an evanescent penetration of the particles into two higher spatial dimensions. Producing an effect identical with the relativistic quantum phenomenon of zitterbewegung, the higher-dimensional oscillations of amplitude ħ/(mc) can be alternatively viewed as a localized curvature of 3D space back and forth into the higher dimensions. The overall spatial curvature is proportional to the particle’s extra-dimensional ground state wave function in the higher-dimensional harmonic confining potential well. Minimizing the overlapping curvature (proportional to the energy) of two particles in proximity to each other, subject to the constraint that for the two particles to occupy the same spatial location one of them must be excited into the 1st excited state of the harmonic potential well, gives the desired NN potential. Specifying only the nucleon masses, the resulting potential well and repulsive core reproduces the radial profile of several published NN central potential models. In addition, the predicted height of the repulsive core, when used to estimate the maximum neutron star mass, matches well with the best estimates from relativistic theory incorporating standard nuclear matter equations of state. Nucleon spin, Coulomb interactions, and internal nucleon structure are not considered in the theory as presented in this article.
Fault-tolerant adaptive and minimal routing in mesh-connected multicomputers using extended safety levels

The minimal routing problem in mesh-connected multicomputers with faulty blocks is studied. Two-dimensional meshes are used to illustrate the approach. A sufficient condition for minimal routing in 2D meshes with faulty blocks is proposed. Unlike many traditional models that assume all the nodes know global fault distribution, our approach is based on the concept of an extended safety level, which is a special form of limited fault information. The extended safety level information is captured by a vector associated with each node. When the safety level of a node reaches a certain level (or meets certain conditions), a minimal path exists from this node to any nonfaulty nodes in 2D meshes. Specifically, we study the existence of minimal paths at a given source node, limited distribution of fault information, and minimal routing itself. We propose three fault-tolerant minimal routing algorithms which are adaptive to allow all messages to use any minimal path. We also provide some general ideas to extend our approaches to other low-dimensional mesh-connected multicomputers such as 2D tori and 3D meshes. Our approach is the first attempt to address adaptive and minimal routing in 2D meshes with faulty blocks using limited fault information.
FISHERY MANAGEMENT IN A HOUSEHOLD ECONOMY: WILL INDIVIDUAL TRANSFERABLE QUOTAS SYSTEM WORK?

Individual transferable quotas system is widely regarded as the best fishery management regime. The literature, however, has ignored the consequence of this managerial system when implemented in an economy where fishermen are both producer and consumer of its own harvest. This article analyzes the behavior of fishing households based on the household model when individual transferable quota system is introduced under missing labor market. It is shown that the individual transferable quotas system could adversely redistribute the quotas through quotas trade and thus cause social inefficiency.
The Penn State Computing Condominium Scheduling System

The Penn State RS/6000 SP is a uniquely acquired and operated computing facility. This 143 CPU machine, centrally located and jointly owned, is a result of collaboration between academic departments, research groups, and the central academic computing facility. It is the largest on- campus resource at Penn State for meeting the high performance computing needs. Due to the joint ownership structure of the machine, the job scheduling requirements are significantly different from the usual methods of job processor allocation in distributed memory parallel machines. After several years of adapting different queuing systems, primarily the Distributed Queuing System, to our needs, it became obvious that the conventional scheduling systems did not serve the machine scheduling requirements unique to the Penn State SP. We concluded that a robust and easily configurable system needs to be developed to meet our unique needs. We have drawn inspiration from and modeled our system on EASY. As with EASY, we use the application programming interface of LoadLeveler to implement our scheduler. Our scheduler is named Penn State Condominium Scheduler (PSCS). PSCS does policy implementation and job execution on the machine is done by LoadLeveler. PSCS is written to facilitate easier configuration and administration. It does not have any processor architecture dependence. It is similar to the native scheduler in LoadLeveler in this regard. PSCS has incorporated three unique features: (i) node owner affinity which ensures fairness by allocation based on ownership, (ii) backfilling which ensures efficient utilization of resources, and (iii) affinity for services provided which ensures proper matching of jobs to the processors based on memory, software and other requirements. Jobs from users who own nodes in the SP complex have affinity to those particular processors owned by them. They also have preferences granted to them depending on their ownership level. Once the demand from the node owners is met, the next important goal is to keep the machine as fully occupied with running jobs as possible. This is accomplished by backfilling. This scheduler incorporates these features which are most important to successful implementation of multi-owner, centrally located, heterogeneous computing facilities.
A hierarchical graph model of the semantics of programs

The problem of developing an adequate formal model for the semantics of programming languages has been under intensive study in recent years. Unlike the area of syntax specification, where adequate models have existed for some time, the area of semantic specification is still in the formative stages. Development of formal semantic models has proceeded along two main lines, lambda-calculus models (e.g., Landin, Strachey) and directed graph models (e.g., Narasimhan, Floyd). This paper describes a model for the semantics of programs based on hierarchies of directed graphs.
The SADC’s Infrastructure : A Regional Perspective

Infrastructure improvements boosted growth in the Southern African Development Community (SADC) by 1.2 percentage points per capita per year during 1995-2005, mainly from access to mobile telephony. Road network improvements made small growth contributions, while power sector inadequacy had a negative impact. Infrastructure improvements that matched those of Mauritius, the regional leader, could boost regional growth performance by 3 percentage points. SADC's 15 member countries include small, isolated economies with island states, a mix of low- and middle-income countries, and larger countries with potentially large economies. The economic geography reinforces the importance of regional infrastructure development to create a larger market and greater economic opportunities. The region's infrastructure indicators are high for Africa. The regional road network is well-developed, and surface transport is comparatively cheap, but subject to delays and long-haul fees. An extensive railway system competes directly with road transport. With integration and improvements, SADC's ports could form an effective transshipment network. Air transport, dominated by South Africa, is the best in Africa. Electricity in southern Africa is well developed; the region leads Africa in generation capacity and low rates, but access is limited. ICT services are the most accessible among the regions, though expensive. Landlocked countries still need to be connected, and greater competition is needed to reduce costs. Completing and maintaining SADC's infrastructure will require $2.1 billion annually for a decade. For small countries, and large countries with small revenues, the burden may be insurmountable without external assistance.
Optimal exchange-rate policy in a low interest rate environment

This paper examines optimal exchange policy when nominal interest rates are unusually low, as experienced by several Asian economies and Japan since July 2006. The paper finds that in such environments, it is optimal to create a nominal depreciation to offset contractionary disturbances. However, the limited scope of monetary policy easing may compromise the ability of the central bank to create a nominal depreciation especially if the central bank makes decisions on monetary policy making on a discretionary basis. In order to successfully create a nominal depreciation, the central bank needs to rely on the expectations channel, by making a credible promise to keep its currency weak going forward. Finally, trade liberalization, by enhancing the role of the exchange rate channel on the transmission mechanism, may allow the central bank to achieve lower average inflation.
Nitric oxide reverses prostaglandin-induced inhibition in ovarian progesterone secretion in rats

The present studies were undertaken to determine whether nitric oxide (NO) is involved in the regulation of ovarian progesterone and oestradiol secretion in rats. Immature female Sprague-Dawley rats at 27 days of age were injected s.c. with 4 IU pregnant mare's serum gonadotrophin (PMSG) and were killed 72 h after the injection. The ovaries were collected, weighed and cultured in Dulbecco's modified Eagle's medium containing saline, NO donor, NO synthesis inhibitor or prostaglandin F2 alpha (PGF2 alpha). After 24 h culture, the medium concentrations of progesterone and oestradiol were measured by radioimmunoassay. Results showed that: (i) diethylenetriamine (DETA)/NO (1 x 10(-6), 1 x 10(-5), 1 x 10(-4) M), an NO donor, caused a dose-dependent increase in progesterone synthesis (355 +/- 43, 443 +/- 46, 647 +/- 55 ng/g ovary respectively, P < 0.01) with a concomitant decrease in ovarian oestradiol secretion (408.1 +/- 50.7, 272.9 +/- 28.2, 132.6 +/- 34.6 pg/g ovary respectively, P < 0.01); (ii) neither progesterone nor oestradiol concentrations in the culture medium were altered by DETA without NO; (iii) NG-nitro-l-arginine methyl ester (1 x 10(-4) M), an inhibitor of NO synthesis, did not significantly affect progesterone and oestradiol secretion by rat ovaries; (iv) PGF2 alpha(1 x 10(-6) M) caused a fall in progesterone and oestradiol synthesis; (v) co-incubation with DETA/NO, significantly reversed the PGF2 alpha-induced decrease in progesterone concentrations from 184 +/- 29 to 388 +/- 60 ng/g (P < 0.01), but not that of oestradiol. It can be concluded that NO up-regulates progesterone secretion and down-regulates oestradiol secretion in rat ovaries, and NO can reverse PGF2 alpha-induced inhibition in ovarian progesterone secretion.
Formation of a trans-bicyclo[3.3.0]Octane by tandem anionic cyclization: evidence for the highly stereoselective irreversible nature of 5-hexen-1-yllithium cyclizations

Abstract Tandem anionic cyclization of 4-ethenyl-6-hepten-1-yllithium ( 7 ), prepared from the corresponding iodide ( 6 ) by low - temperature lithium - iodine exchange, occurs rapidly at room temperature in the presence of TMEDA to give ( trans-3-bicyclo[3.3.0]octyl )methytlithium ( 9 ). Hydrolysis of the reaction mixture delivers 3-methyl- trans -bicyclo[3.3.0]octane in 87% yield.
Policy reforms for sustainable irrigation management – a case study of Indonesia

This paper is based on the results of a one-year study and analysis of irrigated agriculture in Indonesia (1997–98). The overall purpose of the study was to review past policy approaches to irrigation development and management, evaluate their effectiveness, and recommend options for the future. The results show that in spite of large government expenditures in irrigation development, crop productivity (cropping intensity and yields) has remained stagnant through the 1990s. The financial and political crises of 1998 have further led to mass poverty, especially in rural Indonesia. The paper concludes that the Indonesian policy makers must once again restore high-quality rural growth by promoting sustainable uses of land and water resources. It suggests appropriate policy reforms and programs that can promote the desired productivity of irrigated agriculture in Indonesia. Copyright © 2001 John Wiley & Sons, Ltd. Cet article est base sur les resultats d'une analyse des cultures irriguees en Indonesie (1997–98). L'objectif principal consiste a examiner l'efficacite de la politique de gestion et de developpement, et a formuler des recommendations pour l'avenir. Les resultats montrent qu'en depit de ressources gouvernementales considerables, en irrigation, la production agricole (intensite et production) est demeuree stagnante durant la decennie 1990. Les crises financieres et politiques de 1998 ont conduit a la pauvrete, particulierement en Indonesie rurale. En conclusion, la politique en Indonesie devrait voir au developpement de haute qualite en milieu rural en favorisant l'utilisation continue du territoire et des ressources hydriques. L'article suggere des reformes appropriees des programmes visant une productivite accrue des terres irrigues en Indonesie. Copyright © 2001 John Wiley & Sons, Ltd.
A Power Conversion Concept for the Jupiter Icy Moons Orbiter

The Jupiter Icy Moons Orbiter (JIMO) mission is currently under study by the Office of Space Science under the Project Prometheus Program. JIMO is examining the use of Nuclear Electric Propulsion (NEP) to carry scientific payloads to three Jovian moons. A potential power system concept includes dual 100 kWe Brayton converters, a deployable pumped loop heat rejection subsystem, and a 400 Vac Power Management and Distribution (PMAD) bus. Many trades were performed in aniving at this candidate power system concept. System-level studies examined design and off-design operating modes, determined startup requirements, evaluated subsystem redundancy options, and quantified the mass and radiator area of reactor power systems from 20 to 200 kWe. In the Brayton converter subsystem, studies were performed to investigate converter packaging options, and assess the induced torque effects on spacecraft dynamics due to rotating machinery. In the heat rejection subsystem, design trades were conducted on heat transport approaches, material and fluid options, and deployed radiator geometries. In the PMAD subsystem, the overall electrical architecture was defined and trade studies examined distribution approaches, voltage levels, and cabling options.
A Programmable Transformer Coupled Converter for High-Power Space Applications

A programmable transformer coupled converter (PTCC) is being developed by NASA/Marshall Space Flight Center for application in future large space power systems. The PTCC uses an internal microprocessor to control the output characteristics of its three Cuk integrated magnetics type power stages which have a combined capability of 5.4 kW (30 V at 180 A). Details of design trade-offs and test results are presented.
Performance of trellis-coded CPM with iterative demodulation and decoding

Interleaved trellis-coded systems with full response continuous-phase modulation (CPM) are considered. Upper bounds on the bit-error rate performance are derived for coherent detection on the additive white Gaussian noise and flat Rayleigh fading channels by considering the trellis code, interleaver, and CPM modulator as a serially concatenated convolutional code. A coherent receiver that performs iterative demodulation and decoding is shown to provide good bit error performance. Finally, a noncoherent iterative receiver is proposed and is shown to perform close to the coherent iterative receiver.
Creativity and its Correlates in Emotionally Disturbed Preschool Children

Summary.-In the present study, correlational data were gathered on 16 emotionally disturbed preschoolers ranging in age from 3 to G yr. The relationships of interest were those between creativiry, intelligence, the mastery of socioemotional objectives, and the length of time spent in a treatment program for emotionally disturbed children. Also, the amount and nature of the emotionally disturbed children's creativity were compared with the creative behaviors of normal preschool youngsters. The analysis yielded no significant differences between the emotionally disturbed preschoolers and the standardization sample of the creativiry measure. Significant relationships were found between overall creativiry and the mastery of socio-emotional objectives and between length of time in treatment and the scoring category of imagination of the creativity measure. A positive but non-significant correlation was found between the over-all creativity and the intelligence of the disturbed preschoolers. Discussion concerned similarities between therapeutic techniques and methods for fostering creative development as well as the importance of understanding creative strengths in emotionally disturbed children.
Nonlinear Stability of Time-Periodic Viscous Shocks

In order to understand the nonlinear stability of many types of time-periodic travelling waves on unbounded domains, one must overcome two main difficulties: the presence of embedded neutral eigenvalues and the time-dependence of the associated linear operator. This problem is studied in the context of time-periodic Lax shocks in systems of viscous conservation laws. Using spatial dynamics and a decomposition into separate Floquet eigenmodes, it is shown that the linear evolution for the time-dependent operator can be represented using a contour integral similar to that of the standard time-independent case. By decomposing the resulting Green’s distribution, the leading order behavior associated with the embedded eigenvalues is extracted. Sharp pointwise bounds are then obtained, which are used to prove that time-periodic Lax shocks are linearly and nonlinearly stable under the necessary conditions of spectral stability and minimal multiplicity of the translational eigenvalues. The latter conditions hold, for example, for small-oscillation time-periodic waves that emerge through a supercritical Hopf bifurcation from a family of time-independent Lax shocks of possibly large amplitude.
Managing Performance Analysis with Dynamic Statistical Projection Pursuit

Computer systems and applications are growing more complex. Consequently, performance analysis has become more difficult due to the complex, transient interrelationships among runtime components. To diagnose these types of performance issues, developers must use detailed instrumentation to capture a large number of performance metrics. Unfortunately, this instrumentation may actually influence the performance analysis, leading the developer to an ambiguous conclusion. In this paper, we introduce a technique for focussing a performance analysis on interesting performance metrics. This technique, called dynamic statistical projection pursuit, identifies interesting performance metrics that the monitoring system should capture across some number of processors. By reducing the number of performance metrics, projection pursuit can limit the impact of instrumentation on the performance of the target system and can reduce the volume of performance data.
On the ground state wave function of matrix theory

We propose an explicit construction of the leading terms in the asymptotic expansion of the ground state wave function of BFSS SU(N ) matrix quantum mechanics. Our proposal is consistent with the expected factorization property in various limits of the Coulomb branch, and involves a different scaling behavior from previous suggestions. We comment on some possible physical implications.
Characterization and quantification of the role of coherence in ultrafast quantum biological experiments using quantum master equations, atomistic simulations, and quantum process tomography

Long-lived electronic coherences in various photosynthetic complexes at cryogenic and room temperature have generated vigorous efforts both in theory and experiment to understand their origins and explore their potential role to biological function. The ultrafast signals resulting from the experiments that show evidence for these coherences result from many contributions to the molecular polarization. Quantum process tomography (QPT) is a technique whose goal is that of obtaining the time-evolution of all the density matrix elements based on a designed set of experiments with different preparation and measurements. The QPT procedure was conceived in the context of quantum information processing to characterize and understand general quantum evolution of controllable quantum systems, for example while carrying out quantum computational tasks. We introduce our QPT method for ultrafast experiments, and as an illustrative example, apply it to a simulation of a two-chromophore subsystem of the Fenna-Matthews-Olson photosynthetic complex, which was recently shown to have long-lived quantum coherences. Our Fenna-Matthews-Olson model is constructed using an atomistic approach to extract relevant parameters for the simulation of photosynthetic complexes that consists of a quantum mechanics/molecular mechanics approach combined with molecular dynamics and the use of state-of-the-art quantum master equations. We provide a set of methods that allow for quantifying the role of quantum coherence, dephasing, relaxation and other elementary processes in energy transfer efficiency in photosynthetic complexes, based on the information obtained from the atomistic simulations, or, using QPT, directly from the experiment. The ultimate goal of the combination of this diverse set of methodologies is to provide a reliable way of quantifying the role of long-lived quantum coherences and obtain atomistic insight of their causes.
Context-based entropy coding of block transform coefficients for image compression

It has been well established that state-of-the-art wavelet image coders outperform block transform image coders in the rate-distortion (R-D) sense by a wide margin. Wavelet-based JPEG2000 is emerging as the new high-performance international standard for still image compression. An often asked question is: how much of the coding improvement is due to the transform and how much is due to the encoding strategy? Current block transform coders such as JPEG suffer from poor context modeling and fail to take full advantage of correlation in both space and frequency sense. This paper presents a simple, fast, and efficient adaptive block transform image coding algorithm based on a combination of prefiltering, postfiltering, and high-order space-frequency context modeling of block transform coefficients. Despite the simplicity constraints, coding results show that the proposed coder achieves competitive R-D performance compared to the best wavelet coders in the literature.
Pyroxene europium valence oxybarometer: Effects of pyroxene composition, melt composition, and crystallization kinetics

The behavior of multivalent elements such as Fe, Cr, V, and Eu in magmatic systems res ects the fO2 of the environment. In particular, Eu behavior in pyroxene from basaltic systems has been demonstrated to be an effective measure of fO2 . We selected two nearly isochemical lunar pigeonite basalts (15058, 15499), a lunar high-Ti basalt (75035), and Pasamonte (representing asteroid 4 Vesta, an unequilibrated eucrite), to explore other potential variables that may affect this indicator of fO2 . All of these basalts crystallized at an fO2 of approximately IW-1, yet they experienced different cooling and crystallization histories and their pyroxenes exhibit a wide range of compositional trajectories within the pyroxene quadrilateral. There are several variables that ins uence the Eu/Eu* recorded in pyroxene that may compromise the determination of fO2 . Previous experimental studies show that pyroxene composition ins uences the ability of pyroxene to accommodate REE and fractionate Eu 2+ from Eu 3+ . We demonstrate that in addition to the ins uence of Ca in the M2 site, the Al content in the pyroxene and its ins uence on coupled substitutions will also ins uence the fractionation of Eu 2+ from Eu 3+ . For example, the coupled substitution T Si 4+ + M2 R 2+ → T Al 3+ + M2 REE 3+ may accommodate REE 3+
Decoupling capacitor effects on switching noise

The experimental procedures and test vehicles used for the characterization of the decoupling capacitor efficiency in reducing the power supply differential switching noise of the multichip-module (MCM) package structure employed in the IBM ES/9000 system are described. The experimental results are summarized for various switching elements. It is demonstrated that careful design of the test vehicles, tester systems, and probes makes the accurate measurement of Delta-1 noise feasible. Experimental results on the BOBCAT tester show that the decoupling capacitor efficiency in reducing the peak of the differential Delta-1 noise is 50-67%. This efficiency can be increased by reducing the effective inductance in the decoupling capacitor current return path. >
Chiral rhodium(II) carboxamides. A new class of catalysts for enantioselective cyclopropanation reactions

Abstract Chiral Rh2L4 (L = 4-substituted-oxazolidinones and methyl 2-pyrrolidone-5-carboxylate) having two nitrogen-rhodium bonds in the cis geometry at each rhodium face are effective catalysts for enantioselective intermolecular cyclopropanation reactions.
Finite Horizons, Intertemporal Substitution, and Fiscal Policy

This article synthesizes two strands of current macroeconomic research in fiscal policy by allowing for finite lifetimes in an intertemporal substitution model. Among other things, the article establishes that in such a model, public debt issuance is contractionary with respect to current output, a conclusion in strong contrast with conventional macroeconomic analysis.
A Decompilation Approach to Partitioning Software for Microprocessor/FPGA Platforms

In this paper, we present a software compilation approach for microprocessor/FPGA platforms that partitions a software binary onto custom hardware implemented in the FPGA. Our approach imposes less restrictions on software tool flow than previous compiler approaches, allowing software designers to use any software language and compiler. Our approach uses a back-end partitioning tool that utilizes decompilation techniques to recover important high-level information, resulting in performance comparable to high-level compiler-based approaches.
Superconducting Proximity Effect and Majorana Fermions at the Surface of a Topological Insulator

We study the proximity effect between an s-wave superconductor and the surface states of a strong topological insulator. The resulting two-dimensional state resembles a spinless px+ipy superconductor, but does not break time reversal symmetry. This state supports Majorana bound states at vortices. We show that linear junctions between superconductors mediated by the topological insulator form a nonchiral one-dimensional wire for Majorana fermions, and that circuits formed from these junctions provide a method for creating, manipulating, and fusing Majorana bound states.
Necessary and sufficient conditions for parameter convergence in adaptive control

Using Generalized Harmonic Analysis, a complete description of parameter convergence in Model Reference Adaptive Control (MRAC) is given in terms of the spectrum of the exogenous reference input signal. Roughly speaking, if the reference signal 'contains enough frequencies' then the parameter vector converges to its correct value. If not, it converges to an easily characterizable subspace in parameter space.