cssi/SciSciGPT-SciSciNet huggingface dataset:
Independent testing of JWST detector prototypes

The Independent Detector Testing Laboratory (IDTL) is jointly operated by the Space Telescope Science Institute (STScI) and the Johns Hopkins University (JHU), and is assisting the James Webb Space Telescope (JWST) mission in choosing and operating the best near-infrared detectors. The JWST is the centerpiece of the NASA Office of Space Science theme, the Astronomical Search for Origins, and the highest priority astronomy project for the next decade, according to the National Academy of Science. JWST will need to have the sensitivity to see the first light in the Universe to determine how galaxies formed in the web of dark matter that existed when the Universe was in its infancy (z~10-20). To achieve this goal, the JWST Project must pursue an aggressive technology program and advance infrared detectors to performance levels beyond what is now possible. As part of this program, NASA has selected the IDTL to verify comparative performance between prototype JWST detectors developed by Rockwell Scientific (HgCdTe) and Raytheon (InSb). The IDTL is charged with obtaining an independent assessment of the ability of these two competing technologies to achieve the demanding specifications of the JWST program within the 0.6-5 μm bandpass and in an ultra-low background (<0.01 e-/s/pixel) environment. We describe results from the JWST Detector Characterization Project that is being performed in the IDTL. In this project, we are measuring first-order detector parameters, i.e. dark current, read noise, QE, intra-pixel sensitivity, linearity, as functions of temperature, well size, and operational mode.
RF surface resistance tuning of superconducting niobium via thermal diffusion of native oxide

Recently, Nb superconducting radio frequency cavities vacuum heat treated between 300 and 400 °C for a few hours have exhibited very high quality factors (∼5 × 1010 at 2.0 K). Secondary ion mass spectrometry measurements of O, N, and C show that this enhancement in RF surface conductivity is primarily associated with interstitial O alloying via dissolution and diffusion of the native oxide. We use a theory of oxide decomposition and O diffusion to quantify previously unknown parameters crucial in modeling this process. RF measurements of a vacuum heat-treated Nb superconducting radio frequency cavity confirm the minimized surface resistance (higher Q0) previously expected only from 800 °C diffusive alloying with N.
Neural closure models for dynamical systems

Complex dynamical systems are used for predictions in many domains. Because of computational costs, models are truncated, coarsened or aggregated. As the neglected and unresolved terms become impor...
Automating Program Structure Classification

When students write programs, their program structure provides insight into their learning process. However, analyzing program structure by hand is time-consuming, and teachers need better tools for computer-assisted exploration of student solutions. As a first step towards an education-oriented program analysis toolkit, we show how supervised machine learning methods can automatically classify student programs into a predetermined set of high-level structures. We evaluate two models on classifying student solutions to the Rainfall problem: a nearest-neighbors classifier using syntax tree edit distance and a recurrent neural network. We demonstrate that these models can achieve 91% classification accuracy when trained on 108 programs. We further explore the generality, trade-offs, and failure cases of each model.
Microstructure aware modeling of biochemical transport in arterial blood clots.

Abstract Flow-mediated transport of biochemical species is central to thrombotic phenomena. Comprehensive three-dimensional modeling of flow-mediated transport around realistic macroscale thrombi poses challenges owing to their arbitrary heterogeneous microstructure. Here, we develop a microstructure aware model for species transport within and around a macroscale thrombus by devising a custom preconditioned fictitious domain formulation for thrombus–hemodynamics interactions, and coupling it with a fictitious domain advection–diffusion formulation for transport. Microstructural heterogeneities are accounted through a hybrid discrete particle-continuum approach for the thrombus interior. We present systematic numerical investigations on unsteady arterial flow within and around a three-dimensional macroscale thrombus; demonstrate the formation of coherent flow structures around the thrombus which organize advective transport; illustrate the role of the permeation processes at the thrombus boundary and subsequent intra-thrombus transport; and characterize species transport from bulk flow to the thrombus boundary and vice versa.
A Crystal Symmetry-invariant Kobayashi–Warren–Carter Grain Boundary Model and Its Implementation Using a Thresholding Algorithm

Abstract One of the most important aims of grain boundary modeling is to predict the evolution of a large collection of grains in phenomena such as abnormal grain growth, coupled grain boundary motion, and recrystallization that occur under extreme thermomechanical loads. A unified framework to study the coevolution of grain boundaries with bulk plasticity has recently been developed by [1] , which is based on modeling grain boundaries as continuum dislocations governed by an energy based on the Kobayashi–Warren–Carter (KWC) model [2] , [3] . While the resulting unified model demonstrates coupled grain boundary motion and polygonization (seen in recrystallization), it is restricted to grain boundary energies of the Read–Shockley type, which applies only to small misorientation angles. In addition, the implementation of the unified model using finite elements inherits the computational challenges of the KWC model that originate from the singular diffusive nature of its governing equations. The main goal of this study is to generalize the KWC functional to grain boundary energies beyond the Read–Shockley-type that respect the bicrystallography of grain boundaries. The computational challenges of the KWC model are addressed by developing a thresholding method that relies on a primal dual algorithm and the fast marching method, resulting in an O ( N log N ) algorithm, where N is the number of grid points. We validate the model by demonstrating the Herring angle and the von Neumann–Mullins relations, followed by a study of the grain microstructure evolution in a two-dimensional face-centered cubic copper polycrystal with crystal symmetry-invariant grain boundary energy data obtained from the covariance grain boundary model of [4] , [5] .
Model‐assisted analyses of cluster‐randomized experiments

Cluster-randomized experiments are widely used due to their logistical convenience and policy relevance. To analyze them properly, we must address the fact that the treatment is assigned at the cluster level instead of the individual level. Standard analytic strategies are regressions based on individual data, cluster averages, and cluster totals, which differ when the cluster sizes vary. These methods are often motivated by models with strong and unverifiable assumptions, and the choice among them can be subjective. Without any outcome modeling assumption, we evaluate these regression estimators and the associated robust standard errors from a design-based perspective where only the treatment assignment itself is random and controlled by the experimenter. We demonstrate that regression based on cluster averages targets a weighted average treatment effect, regression based on individual data is suboptimal in terms of efficiency, and regression based on cluster totals is consistent and more efficient with a large number of clusters. We highlight the critical role of covariates in improving estimation efficiency, and illustrate the efficiency gain via both simulation studies and data analysis. Moreover, we show that the robust standard errors are convenient approximations to the true asymptotic standard errors under the design-based perspective. Our theory holds even when the outcome models are misspecified, so it is model-assisted rather than model-based. We also extend the theory to a wider class of weighted average treatment effects.
Terrain Adaptive Vehicles

Research on walking vehicles and variable configuration wheeled vehicles is reviewed. The central feature of the vehicles discussed is terrain adaptive capability. The principal elements of the technical problems of coordination and control are discussed for each vehicle type. Examples of each vehicle type are discussed and an extensive reference list is provided. Although the article is primarily a review article, it contains a new discussion of the coordination problem of robotic mechanisms.
Co-worker altruism and unemployment

Abstract It is well-known that social relationships and altruism among workers foster cooperation in the workplace and, therefore, may have beneficial effects for firms. Yet it is unclear how and to what extent co-worker altruism impacts labor market outcomes. In this paper, we find that, although co-worker altruism may be seamless in good times, it may impact the functioning of labor markets during bad times. Specifically, co-worker altruism may potentially lead to wage rigidity and involuntary unemployment in economic downturns. These results seem to be consistent with recent empirical findings.
Partially pooled propensity score models for average treatment effect estimation with multilevel data

Causal inference analyses often use existing observational data, which in many cases has some clustering of individuals. In this paper we discuss propensity score weighting methods in a multilevel setting where within clusters individuals share unmeasured confounders that are related to treatment assignment and the potential outcomes. We focus in particular on settings where models with fixed cluster effects are either not feasible or not useful due to the presence of a large number of small clusters. We found, both through numerical experiments and theoretical derivations, that a strategy of grouping clusters with similar treatment prevalence and estimating propensity scores within such cluster groups is effective in reducing bias from unmeasured cluster-level covariates under mild conditions on the outcome model. We apply our proposed method in evaluating the effectiveness of center-based pre-school program participation on children's achievement at kindergarten, using the Early Childhood Longitudinal Study, Kindergarten data.
Information Theoretic Secure Aggregation with User Dropouts

In the robust secure aggregation problem, a server wishes to learn and only learn the sum of the inputs of a number of users while some users may drop out (i.e., may not respond). The identity of the dropped users is not known a priori and the server needs to securely recover the sum of the remaining surviving users. We consider the following minimal two-round model of secure aggregation. Over the first round, any set of no fewer than $U$ users out of $K$ users respond to the server and the server wants to learn the sum of the inputs of all responding users. The remaining users are viewed as dropped. Over the second round, any set of no fewer than $U$ users of the surviving users respond (i.e., dropouts are still possible over the second round) and from the information obtained from the surviving users over the two rounds, the server can decode the desired sum. The security constraint is that even if the server colludes with any $T$ users and the messages from the dropped users are received by the server (e.g., delayed packets), the server is not able to infer any additional information beyond the sum in the information theoretic sense. For this information theoretic secure aggregation problem, we characterize the optimal communication cost. When $U\leq T$ , secure aggregation is not feasible, and when $U > T$ , to securely compute one symbol of the sum, the minimum number of symbols sent from each user to the server is 1 over the first round, and $1/(U-T)$ over the second round.
Efficient linear dsDNA tagging using deoxyuridine excision.

Site-specific strategies for exchanging segments of dsDNA are important for DNA library construction and molecular tagging. Deoxyuridine (dU) excision is an approach for generating 3' ssDNA overhangs in gene assembly and molecular cloning procedures. Unlike approaches that use a multi-base pair motif to specify a DNA cut site, dU excision requires only a dTâdU substitution. Consequently, excision sites can be embedded in biologically active DNA sequences by placing dU substitutions at non-perturbative positions. In this work, I describe a molecular tagging method that uses dU excision to exchange a segment of a dsDNA strand with a long synthetic oligonucleotide. The core workflow of this method, called deoxyUridine eXcision-tagging (dUX-tagging), is an efficient one-pot reaction: strategically positioned dU nucleotides are excised from dsDNA to generate a 3' overhang so that additional sequence can be appended by annealing and ligating a tagging oligonucleotide. The tagged DNA is then processed by one of two procedures to fill the 5' overhang and remove excess tagging oligo. To facilitate its widespread use, all dUX-tagging procedures exclusively use commercially available reagents. As a result, dUX-tagging is a concise and easily implemented approach for high-efficiency linear dsDNA tagging.
Effective voice: Beyond exit and affect in online communities:

Online communities provide ample opportunities for user self-expression but generally lack the means for average users to exercise direct control over community policies. This article sets out to i...
Multilinear Algebra for Distributed Storage

Exact-repair regenerating codes (ERRCs) are a class of codes designed for distributed storage systems. A distributed storage system is a collection of devices that collaborate to store a large file...
USP21 and OTUD3 Antagonize Regulatory Ribosomal Ubiquitylation and Ribosome-Associated Quality Control

Defects within mRNAs or nascent chains that halt ribosomal progression can trigger ribosomeassociated quality control (RQC) pathways that facilitate mRNA and nascent polypeptide destruction as well as ribosome recycling. Failure to remove defective mRNAs or nascent chains can lead to the accumulation of cytotoxic protein aggregates and proteotoxic stress. We previously established that the E3 ligase ZNF598 catalyzes regulatory ribosomal ubiquitylation of specific 40S ribosomal proteins required for downstream RQC events. Utilizing an optical RQC reporter we identify OTUD3 and USP21 as deubiquitylating enzymes that antagonize ZNF598-mediated 40S ubiquitylation and facilitate ribosomal deubiquitylation following RQC activation. Overexpression of either USP21 or OTUD3 enhances readthrough of stall-inducing sequences as compared to knock-in cells lacking individual RRub sites suggesting that combinatorial ubiquitylation of RPS10 (eS10) and RPS20 (uS10) is required for optimal resolution of RQC events and that deubiquitylating enzymes can limit RQC activation.
Tusas: A fully implicit parallel approach for coupled phase-field equations

Abstract We develop a fully-coupled, fully-implicit approach for phase-field modeling of solidification in metals and alloys. Predictive simulation of solidification in pure metals and metal alloys remains a significant challenge in the field of materials science, as microstructure formation during the solidification process plays a critical role in the properties and performance of the solid material. Our simulation approach consists of a finite element spatial discretization of the fully-coupled nonlinear system of partial differential equations at the microscale, which is treated implicitly in time with a preconditioned Jacobian-free Newton-Krylov method. The approach is algorithmically scalable as well as efficient due to an effective preconditioning strategy based on algebraic multigrid and block factorization. We implement this approach in the open-source Tusas framework, which is a general, flexible tool developed in C++ for solving coupled systems of nonlinear partial differential equations. The performance of our approach is analyzed in terms of algorithmic scalability and efficiency, while the computational performance of Tusas is presented in terms of parallel scalability and efficiency on emerging heterogeneous architectures. We demonstrate that modern algorithms, discretizations, and computational science, and heterogeneous hardware provide a robust route for predictive phase-field simulation of microstructure evolution during additive manufacturing.
Local finite element approximation of Sobolev differential forms

We address fundamental aspects in the approximation theory of vector-valued finite element methods, using finite element exterior calculus as a unifying framework. We generalize the Clement interpolant and the Scott-Zhang interpolant to finite element differential forms, and we derive a broken Bramble-Hilbert lemma. Our interpolants require only minimal smoothness assumptions and respect partial boundary conditions. This permits us to state local error estimates in terms of the mesh size. Our theoretical results apply to curl-conforming and divergence-conforming finite element methods over simplicial triangulations.
On the stabilization of relative trace formulae: Descent and the fundamental lemma

Abstract Motivated by the study of periods of automorphic forms and relative trace formulae, we develop the theory of descent necessary to study orbital integrals arising in the fundamental lemma for a general class of symmetric spaces over a p-adic field F. More precisely, we prove that a connected symmetric space over F enjoys a notion of topological Jordan decomposition, which may be of independent interest, and establish a relative version of a lemma of Kazhdan that played a crucial role in the proof of the Langlands–Shelstad fundamental lemma. As our main application, we use these results to prove the endoscopic fundamental lemma for the unit element of the Hecke algebra for the symmetric space associated to unitary Friedberg–Jacquet periods.
Quantization of gravity in spherical harmonic basis

We perform canonical quantization of gravity in the background of a Schwarzschild black hole in the generalized Regge-Wheeler gauge proposed in Kallosh and Rahman [Quantization of gravity in the black hole background, Phys. Rev. D 104, 086008 (2021)]. We find that the Hamiltonian at the quadratic level is unitary and ghost-free. Two canonical degrees of freedom are associated with Zerilli-Moncrief and Cunningham-Price-Moncrief functions of the metric perturbations. The $\ensuremath{\ell}l2$ part of the Hamiltonian vanishes. This quantization with the unitary Hamiltonian for gravity is valid also in Minkowski space in spherical coordinates.
Advances in trajectory optimization for space vehicle control

Abstract Space mission design places a premium on cost and operational efficiency. The search for new science and life beyond Earth calls for spacecraft that can deliver scientific payloads to geologically rich yet hazardous landing sites. At the same time, the last four decades of optimization research have put a suite of powerful optimization tools at the fingertips of the controls engineer. As we enter the new decade, optimization theory, algorithms, and software tooling have reached a critical mass to start seeing serious application in space vehicle guidance and control systems. This survey paper provides a detailed overview of recent advances, successes, and promising directions for optimization-based space vehicle control. The considered applications include planetary landing, rendezvous and proximity operations, small body landing, constrained attitude reorientation, endo-atmospheric flight including ascent and reentry, and orbit transfer and injection. The primary focus is on the last ten years of progress, which have seen a veritable rise in the number of applications using three core technologies: lossless convexification, sequential convex programming, and model predictive control. The reader will come away with a well-rounded understanding of the state-of-the-art in each space vehicle control application, and will be well positioned to tackle important current open problems using convex optimization as a core technology.
The Gross–Zagier–Zhang formula over function fields

We prove the Gross–Zagier–Zhang formula over global function fields of arbitrary characteristics. It is an explicit formula which relates the Neron-Tate heights of CM points on abelian varieties and central derivatives of associated quadratic base change L-functions. Our proof is based on an arithmetic variant of a relative trace identity of Jacquet. This approach is proposed by Zhang. We apply our results to the Birch and Swinnerton–Dyer conjecture for abelian varieties of $${\mathrm {GL}}_2$$ -type. In particular, we prove the conjecture for elliptic curves of analytic rank 1.
Decentralized Time and Energy-Optimal Control of Connected and Automated Vehicles in a Roundabout

We consider the problem of controlling Connected and Automated Vehicles (CAVs) traveling through a three-entry roundabout so as to jointly minimize the travel time and energy consumption while providing speed-dependent safety guarantees and satisfying velocity and acceleration constraints. We first design a systematic approach to dynamically determine all conflicting CAVs defining the safety constraints under different CAV sequencing policies. A joint optimal control and barrier function (OCBF) method is then applied to efficiently obtain a controller that optimally tracks the unconstrained optimal control solution while guaranteeing the satisfaction of all constraints. Simulation experiments performed to compare the OCBF controller to a baseline of human-driven vehicles show its effectiveness under different roundabout configurations and sequencing policies.
Learning Treatment Effects in Panels with General Intervention Patterns

The problem of causal inference with panel data is a central econometric question. The following is a fundamental version of this problem: Let $M^*$ be a low rank matrix and $E$ be a zero-mean noise matrix. For a `treatment' matrix $Z$ with entries in $\{0,1\}$ we observe the matrix $O$ with entries $O_{ij} := M^*_{ij} + E_{ij} + \mathcal{T}_{ij} Z_{ij}$ where $\mathcal{T}_{ij} $ are unknown, heterogenous treatment effects. The problem requires we estimate the average treatment effect $\tau^* := \sum_{ij} \mathcal{T}_{ij} Z_{ij} / \sum_{ij} Z_{ij}$. The synthetic control paradigm provides an approach to estimating $\tau^*$ when $Z$ places support on a single row. This paper extends that framework to allow rate-optimal recovery of $\tau^*$ for general $Z$, thus broadly expanding its applicability. Our guarantees are the first of their type in this general setting. Computational experiments on synthetic and real-world data show a substantial advantage over competing estimators.
Health endowments, schooling allocation in the family, and longevity: Evidence from US twins.

Abstract We analyze data from the Minnesota Twin Registry (MTR), combined with the Socioeconomic Survey of Twins (SST), and new mortality data, and contribute to two bodies of literature. First, we demonstrate a beneficial causal effect of education on health and longevity in contrast to other twin-based studies of the US population, which show little or no effect of education on health. Second, we present evidence that is consistent with parental compensation through education for differences in their children’s endowments that predict health, but find no evidence that parents reinforce differences in endowments that predict earnings. We argue that there is a bias towards detecting reinforcement both in this paper and in the literature. Despite this bias, we still find statistical evidence of compensating behavior. We account for observed and unobserved confounding factors, sample selection bias, and measurement error in education.
If You Build It, “They/Them” Will Come: The Misgendering of Transgender Nonbinary Athletes Is Discrimination on the Basis of Sex

This article provides necessary context to adequately engage in a discussion about transgender and nonbinary individuals, including defined terms. It then provides a brief history of Title IX, articulates the requirements for compliance with the statute, and discusses its application to transgender athletes. Next, this article provides an overview of Title VII of The Civil Rights Act of 1964 and the recent statutory analysis of its prohibition on employment discrimination because of sex in Bostock v. Clayton County extends that analysis to the statutory language of Title IX, and summarizes the recent interpretation by the Department of Education applying that analysis to Title IX. The article then discusses the implications of the persistent misgendering of transgender nonbinary athletes and argues that only by allowing all athletes to compete as their true gender will the inclusive goals of Title IX be realized. The article concludes that the requirements for Title IX compliance are not inclusive of transgender nonbinary athletes and contradictory to the prohibition on discrimination on the basis of sex articulated by the statute itself. The article proposes several necessary changes to the language of those requirements for compliance and argues that the Department of Education must make changes in its interpretation toward more inclusive language to truly achieve the goals of Title IX.
Empirical Evidence on Jumps and Large Fluctuations in Individual Stocks

We make use of the extant testing methodology of Barndorff-Nielsen and Shephard (2006) and Ait-Sahalia and Jacod (2009a, b, c) to examine the importance of jumps, and in particular “large” and “small” jumps, using high frequency price returns on 25 stocks in the DOW 30 and S&P futures index. In particular, we examine jumps from both the perspective of their contribution to overall realized variation and their contribution to predictive regressions of realized volatility. We find evidence of jumps in around 22.8% of the days during the 1993-2000 period, and in 9.4% of the days during the 2001-2008 period, which implies more (jump induced) turbulence in financial markets in the previous decade than the current decade. Also, it appears that frequent “small” jumps of the 1990s have been replaced to some extent with relatively infrequent “large” jumps in recent years. Interestingly, this result holds for all of the stocks that we examine, supporting the notion that there is strong comovement across jump components for a wide variety of stocks, as discussed in Bollerslev, Law and Tauchen (2008). In our prediction experiments using the class of linear and nonlinear HAR-RV, HAR-RV-J and HAR-RV-CJ models proposed by Muller, Dacorogna, Dave, Olsen, Puctet, and von Weizsackeret (1997), Corsi (2004) and Andersen, Bollerslev and Diebold (2007). We find that the “linear” model performs well for only very few stocks, while there is significant improvement when instead using the “square root” model. Interestingly, the “log” model, which performs very well in their study of market indices, performs approximately equally as well as the square root model when our longer sample of market index data is used. Moreover, the log model, while yielding marked predictability improvements for individual stocks, can actually only be implemented for 7 of our 25 stocks, due to data singularity issues associated with the incidence of jumps at the level of individual stocks.
Stratum Corneum Defensive Functions: An Integrated View

Most epidermal functions can be considered as protective, or more specifically, as defensive in nature. Yet, the term "barrier function" is often used synonymously with only one such defensive function, though arguably its most important, i.e., permeability barrier homeostasis. Regardless of their relative importance, these protective cutaneous functions largely reside in the stratum corneum (SC). In this review, I first explore the ways in which the multiple defensive functions of the SC are linked and interrelated, either by their shared localization or by common biochemical processes; how they are co-regulated in response to specific stressors; and how alterations in one defensive function impact other protective functions. Then, the structural and biochemical basis for these defensive functions is reviewed, including metabolic responses and signaling mechanisms of barrier homeostasis. Finally, the clinical consequences and therapeutic implications of this integrated perspective are provided.
Transcription and Alignment of the TIMIT Database

Publisher Summary The TIMIT acoustic-phonetic database was designed jointly by researchers at MIT, TI, and SRI. It was intended to provide a rich collection of acoustic phonetic and phonological data, to be used for basic research as well as the development and evaluation of speech recognition systems. There are a total of 450 MIT sentences used in the TIMIT database. These were generated by hand in an iterative fashion, with the goal that they should be phonetically rich. To aid in the sentence generation process, Webster's Pocket Dictionary is used which, contains nearly 20,000 words. Words or word-sequences containing particular phone pairs could be accessed from this dictionary automatically, which greatly facilitated the database design process. The database consists of a total of 6,300 sentences from 639 speakers, representing over 5 hours of speech material, and was recorded by researchers at TI. This chapter describes the transcription and alignment of the TIMIT database, which was performed at MIT.
The relationship of salt to hypertension.

The background information is reviewed regarding the American Society for Clinical Nutrition task force consensus statement on salt. Information links hypertension to dietary sodium. Only a fraction (between 9 and 20 percent) of human subjects are genetically susceptible to developing hypertension by middle life. Within this group, a lifelong restriction of NaCl intake to levels less than 60 mEq/day in adults will probably prevent hypertension indefinitely. It requires a much lower level of Na intake to reduce established hypertension, as little as 20 mEq/day to reduce severe levels. Control of body weight and correction of obesity are beneficial for the prevention and treatment of hypertension. The risk of a low sodium diet to individuals with salt-losing renal disease or adrenal insufficiency would be profound
Optical properties of artificial non-heme iron proteins derived from bovine serum albumin.

Abstract Three types of artificial non-heme iron proteins can be prepared from bovine serum albumin. Two of these are prepared by incubating serum albumin with iron either in the presence or absence of 2-mercaptoethanol. A third type is prepared by incubating serum albumin with 2-mercaptoethanol, iron, and inorganic sulfide. The latter type resembles ferredoxin spectrally and contains 5 to 8 moles of iron and 4 to 7 moles of inorganic sulfide per mole of protein. This protein-iron-sulfide complex however can be distinguished from the ferredoxin, adrenodoxin, and rubredoxin by comparison of the circular dichroic spectra. The Cotton effects in the 300 to 350 mµ region have been provisionally assigned to electronic transitions arising from the iron-protein interaction, whereas the Cotton effects in 350 to 440 mµ region appear to be related to iron-sulfide interaction.
Identification with the Aggressor

In the early 1970s, four Swedish men were held captive in a bank vault for six days during a robbery attempt. The captives reported an emotional bonding with their captors, essentially identifying with their aggressors; this phenomenon was dubbed the Stockholm syndrome. Keywords: alcohol; antianxiety drugs; video games; Stockholm syndrome; Patty hearst
Systems research at WARDA

WARDA was restructured and became a CGIAR center in 1986. Research is organized by ecosystems, including the upland-inland valley swamp continuum, the Sahel irrigated rice ecosystem, and the mangrove rice ecosystem programs. This paper discusses the institutional and collaborative requirements for systems research in West Africa. It also proposes a symmetry in complexity and integration between researched system and research system. An open-center concept was developed at WARDA as a means to achieve a critical mass of scientists and to encourage a more interdisciplinary and interinstitutional integration for systems research. Examples of the concept are the task-force system that integrates the effects of NARS and WARDA, the consortium program that focuses on inland valleys in the humid zone, and the Sahel diagnostic network that emphasizes crop-climate interactions in the arid zone. A need to intensify training programs to achieve full NARS-IARC partnership in systems research has been identified. WARDA’s systems research on Sahel irrigated rice is presented in more detail, with an emphasis on cropping calendar x genotype x climate interactions. The regional variations in crop calendars was analyzed and explained using simulation methods. Improvements are now sought through breeding and organizational studies at the level of the village or irrigation scheme.
The biological profile of PD 0325901: A second generation analog of CI-1040 with improved pharmaceutical potential

4003 CI-1040, the first MEK inhibitor to enter clinical evaluation, was advanced into development based on promising preclinical activity. While Phase 1 data pointed to promising hints of clinical activity, efficacy in Phase 2 single agent screening studies was insufficient to warrant continued development. Target suppression in Phase 1 tumor biopsies was 50% at 24 hours post-dosing. In comparison, CI-1040 at a much higher dose (150 mg/kg) could only inhibit pERK levels for roughly 8 hours, returning to control levels by 24 hours after treatment. Oral efficacy comparisons revealed that the dose required to produce a 70% incidence of complete tumor responses (C26 model) was 25 mg/kg/day versus 900 mg/kg/day for PD0325901 and CI-1040, respectively. Anticancer activity of PD 0325901 has been demonstrated for a broad spectrum of human tumor xenografts, significantly inhibiting the growth of 6 out of 7 human tumor models tested. PD 0325901 was also shown to be highly efficacious and effective at inhibiting ERK phosphorylation when administered by the IV route. The improved anticancer activity of PD0325901 compared to CI-1040 is likely due to several contributing pharmacological factors, including longer duration and greater potency of MEK inhibition, as well as greater solubility leading to improved bioavailability, and increased metabolic stability. Based on its highly specific inhibition of MEK and its overall pharmaceutical profile, PD0325901 has the potential to provide ultimate validation of MEK as an anticancer drug target. Phase 1 trials with this agent are underway.
Epidermal growth factor-mediated effects on equine vascular smooth muscle cells

Epidermal growth factor (EGF) receptor binding kinetics and EGF-mediated stimulation of DNA synthesis and cellular proliferation were studied in cultured vascular smooth muscle cells (VSMC) from the equine thoracic aorta. Binding studies, using murine 125I-labeled EGF, indicate the presence of a single class of high-affinity binding sites (apparent KD = 2.8 X 10(-11) M), with an estimated maximal binding capacity of 5,800 sites/cell. EGF stimulated [3H]thymidine uptake in confluent quiescent monolayers in a dose-dependent fashion, half-maximal stimulation occurring at 7.5 X 10(-11) M. Likewise, EGF-mediated cellular proliferation was dose dependent (50% effective dose = 5 X 10(-11) M) under reduced serum concentrations. Equine VSMC contain specific receptors for EGF, and EGF can stimulate DNA synthesis and proliferation in these cultured cells, which suggests that EGF may participate in the proliferative changes observed in equine distal digital peripheral vascular disease.
Baudelaire et L'art Espagnol: Poésie, esthétique, critique d’art

Among writers interested in Spain, Baudelaire seems to have had a singular perspective on documents related to travel in Spain and Spanish works of art. The tragic and melancholic sensibility that characterizes Baudelaire's writing goes beyond considerations of local color. Through his readings and assiduous gallery visits, Baudelaire develops his own thought, strangely detached from widespread stereotypes of exoticism and alterity. His distinctive method of combining the Beautiful and the bizarre leads him toward the strangeness of the baroque. As a writer and poet, Baudelaire goes to the heart of Spanish aesthetics in some of his least-known writings, including several poems in The Flowers of Evil. Keywords: Baudelaire, Spain, aesthetics, poetry, art, Flowers of Evil.
Cellular robotic system with stationary robots and its application to manufacturing lattices

Cellular robotic systems (CRS) use a large number of robots operating in a cellular space under distributed control. A subclass, CRS with stationary robots and passive objects (SCRS), is examined. An SCRS consists of an array of stationary robots at fixed locations. They are used to manipulate a collection of objects within the cellular space such that predefined (global) static and dynamic properties for the 'field' of objects are induced by distributed algorithms. Example protocols of 1D SCRS that form various patterns of objects are presented. As an application of SCRS, a manufacturing lattice (ML) is defined as a collection of uniformly shaped and densely packed cells. Typical geometric shapes of ML cells are rectangular, rhombus, hexagonal, or triangle. MLs support batch processing of single products as well as flexible manufacturing and prototyping. The proposed mechanical structure and electrical control mechanism of MLs are also discussed. >
Longitudinal distribution of canine respiratory heat and water exchanges.

We assessed the longitudinal distribution of intra-airway heat and water exchanges and their effects on airway wall temperature by directly measuring respiratory fluctuations in airstream temperatu...
Preparation of cross sections of thin-coated sheet steel for analytical electron microscopy observation

A method of preparing thinned cross sections of coated sheet steel (Galvalume) for observation in an analytical electron microscope (AEM) was developed. Steel panels dipped for 4 sec in baths of 55% by weight (wt pct) Al-1.7 wt pct Si-balance Zn, and 55 wt pct Al-6.88 wt pct Si-balance Zn at 610°C were examined. The ratio of the intensity of the K and L x-ray lines from the same element was used in determining the foil thickness. The AEM results compared favorably to results obtained using electron microprobe analysis (EMPA).
Translational applications of evaluating physiologic variability in human endotoxemia

Dysregulation of the inflammatory response is a critical component of many clinically challenging disorders such as sepsis. Inflammation is a biological process designed to lead to healing and recovery, ultimately restoring homeostasis; however, the failure to fully achieve those beneficial results can leave a patient in a dangerous persistent inflammatory state. One of the primary challenges in developing novel therapies in this area is that inflammation is comprised of a complex network of interacting pathways. Here, we discuss our approaches towards addressing this problem through computational systems biology, with a particular focus on how the presence of biological rhythms and the disruption of these rhythms in inflammation may be applied in a translational context. By leveraging the information content embedded in physiologic variability, ranging in scale from oscillations in autonomic activity driving short-term heart rate variability to circadian rhythms in immunomodulatory hormones, there is significant potential to gain insight into the underlying physiology.
Top Ten List in Sepsis

Schroder and colleagues expand our growing knowledge of genetic predisposition to septic shock by examining the relationship of gender to tumor necrosis factor (TNF)gene Nco1 polymorphism. Several recent reports indicate that patients who possess the TNF2 homozygous genotype for this polymorphism have a higher incidence of severe sepsis, higher TNFserum concentrations, and a lower likelihood of survival once sepsis develops. In this prospective study of 201 patients with severe sepsis, the 68 women had a higher survival rate than the men, but no association of survival to different genotypes was found in women. In contrast, the mortality rate was significantly increased in 133 men who were homozygous for TNF2 compared to other genotypes. Since previous sepsis studies from the same investigators demonstrated higher interleukin (IL)-10 levels in women and higher TNFlevels in men, it may be that genetically determined patterns of cytokine response to injury or infection may differ among the sexes and may influence outcome.
Phytoplankton associations with the variable nepheloid layer on the Texas continental shelf

Four 24-h cruises occupied a station at 33m depth on the Texas continental shelf during June, July, September and November 1978. Samples collected at 4-h intervals investigated the state of selected physical, chemical and biological factors potentially important to phytoplankton associated with the nepheloid layer. The nepheloid layer varied in thickness and in density within and between cruises. Phytoplankton biomass was differentially associated with the nepheloid layer in June and July but not in September and November. The first two cruises showed a mixed phytoplankton community (>20μm) composed of pelagic and benthic species and a net carbon-fixation within the nepheloid layer. Based on photic zone depth, enhanced phytoplankton biomass resulting from growth can theoretically accumulate within the nepheloid layer between the coast and the 70-m contour from July to September. This phytoplankton concentration may provide an important food reservoir to eligible herbivores during the summer months.
Eye colours in the parasitic waspHabrobracon and their behaviour in multiple recessives and in mosaics

1. Four loci for eye-colour differences have been found inHabrobracon. They segregate independently.
Molecular Detection of Culture-Confirmed Bacterial Bloodstream Infections with Limited Enrichment Time

Conventional blood culturing using automated instrumentation with phenotypic identification requires a significant amount of time to generate results. This study investigated the speed and accuracy of results generated using PCR and pyrosequencing compared to the time required to obtain Gram stain results and final culture identification for cases of culture-confirmed bloodstream infections. Research and physician-ordered blood cultures were drawn concurrently. Aliquots of the incubating research blood culture fluid were removed hourly between 5 and 8 h, at 24 h, and again at 5 days. DNA was extracted from these 6 time point aliquots and analyzed by PCR and pyrosequencing for bacterial rRNA gene targets. These results were then compared to those of the physician-ordered blood culture. PCR and pyrosequencing accurately identified 92% of all culture-confirmed cases after a mean enrichment time of 5.8 ± 2.9 h. When the time needed to complete sample processing was included for PCR and pyrosequencing protocols, the molecular approach yielded results in 11.8 ± 2.9 h compared to means of 27.9 ± 13.6 h to obtain the Gram stain results and 81.6 ± 24.0 h to generate the final culture-based identification. The molecular approach enabled accurate detection of most bacteria present in incubating blood culture bottles on average about 16 h sooner than Gram stain results became available and approximately 3 days sooner than the phenotypic identification was entered in the Laboratory Information System. If implemented, this more rapid molecular approach could minimize the number of doses of unnecessary or ineffective antibiotics administered to patients.
Effects of organization and semantic similarity on recall and recognition

Three experiments were performed to extend the previous finding that number of cate-gories (NC) in organized, categorized lists determines the number of words recalled. The NC also influences recognition both in immediate tests and in a delay of two weeks. False alarm rates in recognition are generally unaffected by the use of synonyms as fillers, suggesting that perceptual features of words are used at least in addition to semantic features. To accommodate the novel finding that organization affects recognition, a model for the case of subject-organized lists was presented which introduces the notion of a postrecognition retrieval check. Previous findings on the relation between NC and recall were replicated.
Simultaneous measurement of adenosine and hypoxanthine in human umbilical cord plasma using reversed-phase high-performance liquid chromatography with photodiode-array detection and on-line validation of peak purity.

Abstract A new, robust and sensitive reversed-phase high-performance liquid chromatographic method was developed for concomitant measurement of plasma concentrations of the ATP catabolites adenosine and hypoxanthine in human umbilical cord blood. Deproteinized cord plasma was chromatographed on Hypersil C 18 columns, using UV photodiode-array detection, spectral analysis of peaks and on-line confirmation of peak purity. Elution with a gradient of acetonitrile–tetrahydrofuran in ammonium dihydrogen phosphate buffer pH 4.7, yielded sharp, well-resolved peaks of adenosine and hypoxanthine within 16 min. Peak areas were quantified from external calibration curves and converted to plasma concentrations via cord blood hematocrits. In seven deliveries, gestational ages 32–40 weeks, adenosine (range, 0.1–2.1 μ M ) was less than hypoxanthine (range, 1.6–18.5 μ M ) in the same cord plasma sample. Arteriovenous levels of each purine were similar, except in an abruptio placenta delivery.
The graph-theoretic analogue of Tietze's characterization of a convex set and its generalization†

Introduction. One of the most satisfying theorems in the theory of convex sets states that a closed connected subset of a topological linear space which is locally convex is convex. This was first established in En by Tietze and was later extended by other authors (see (3)) to a topological linear space. A generalization of Tietze's theorem which appears in (2) shows if S is a closed subset of a topological linear space such that the set Q of points of local non-convexity of S is of cardinality n < ∞ and S ~ Q is connected, then S is the union of n + 1 or fewer convex sets. (The case n = 0 is Tietze's theorem.)