cssi/SciSciGPT-SciSciNet huggingface dataset:
Data-Driven Iterative Trajectory Shaping for Precision Control of Flexible Feed Drives

With recent advances on material processing technologies, design requirements on modern manufacturing equipment are shifting toward achieving higher speed and accuracy rather than stiffness and load capacity. Motion systems used in additive or ultraprecision manufacturing equipment need to be designed to achieve greater dynamic positioning accuracy. As a result, feedforward (FF) control becomes an effective tool. This article presents a novel and practical FF controller design methodology to widen tracking bandwidth of precision motion systems suffering from structural dynamics and friction-induced disturbances. The proposed feedforward controller is designed to, first, compensate for the closed-loop servo dynamics to widen the command tracking bandwidth, second, mitigate unwanted vibrations, and third, compensate friction disturbance-induced positioning errors. The FF controller is structured in a trajectory prefilter form where the FF compensation signal is injected into the reference trajectory rather than torque command. This facilitates the FF controller to be applied conveniently without intervention with the servo controller. FF controller parameters are identified (tuned) automatically through machine in-the-loop-iterations. Parameter identification is posed as a convex optimization problem to realize safe and reliable auto-tuning. The proposed FF controller and its parameter tuning methodology are tested experimentally on an industrial scale multiaxis machine tool and its performance is validated.
Trans sanctity: Medievalism and the Vírgenes de la Puerta

This article introduces the reader to the photographic series Virgenes de la Puerta by Juan Jose Barboza-Gubo and Andrew Mroczek. The series has met with critical acclaim for the raw power of its images and has reached audiences across continents. The virgenes in these photographs are all transgender women of color living in Lima, Peru, and the series vividly and unapologetically portrays them as living saints. In this article, I discuss how the photographs appeal to a long history of sainthood and sanctity. Moreover, I argue that depicting the virgenes as living saints challenges the reader to re-consider Christian hamartiology: the virgenes invert a savior-saved dialectic and force the reader to imagine trans futures as well as the role of trans bodies and souls in a greater cosmology.
Complement Upregulates Runx-2 to Induce Profibrogenic Change in Aortic Valve Interstitial Cells

Abstract Background Calcium accumulation and fibrotic activities are principal mechanisms for calcific aortic valve disease (CAVD). Active complement products are observed in human stenotic aortic valves. Runt-related transcription factor 2 (Runx-2) is involved in tissue calcification. We hypothesized that complement upregulates Runx-2 to induce profibrogenic change in human aortic valve interstitial cells (AVICs). Methods AVICs were isolated from 6 normal and 6 CAVD donor valves. Cells were treated with complement cocktails. Profibrogenic activities and associated signaling molecules were analyzed by Western blot assay and collagen staining. Results Complement time and dose dependently enhanced profibrogenic activities in AVICs, and complement exposure also induced total collagen deposition in AVICs. Complement-induced profibrogenic responses were associated with increased Runx-2 expression and phosphorylation of extracellular signal-regulated kinase 1 and 2 (ERK1/2). Genetic silencing of Runx-2 decreased both matrix metalloproteinase 9 (MMP-9) and collagen I levels. Pharmacological inhibition of ERK1/2 decreased complement-mediated MMP-9, collagen I, and Runx-2 expression as well as total collagen deposition in human AVICs. Further, treating AVICs with heat-deactivated complement resulted in reduced MMP-9, collagen I, and Runx-2 levels compared with active complement treatment. Conclusions Complement induced profibrogenic activities in AVICs by activation of ERK1/2–mediated Runx-2 signaling pathways. This study demonstrates a potential role for complement-mediated CAVD pathogenesis, establishing a possible therapeutic target to limit CAVD progression.
Learning Proofs of Motion Planning Infeasibility

We present a learning-based approach to prove infeasibility of kinematic motion planning problems. Sampling-based motion planners are effective in high-dimensional spaces but are only probabilistically complete. Consequently, these planners cannot provide a definite answer if no plan exists, which is important for high-level scenarios, such as task-motion planning. We propose a combination of bidirectional sampling-based planning (such as RRT-connect) and machine learning to construct an infeasibility proof alongside the two search trees. An infeasibility proof is a closed manifold in the obstacle region of the configuration space that separates the start and goal into disconnected components of the free configuration space. We train the manifold using common machine learning techniques and then triangulate the manifold into a polytope to prove containment in the obstacle region. Under assumptions about learning hyper-parameters and robustness of configuration space optimization, the output is either an infeasibility proof or a motion plan. We demonstrate proof construction for 3-DOF and 4-DOF manipulators and show improvement over previous algorithms.
A Monocot Flower, Mirafloris burmitis gen. et sp. nov. (Monocots: Angiospermae), in Burmese Amber

A six-merous, slightly bisymmetric monocot flower in mid-Cretaceous Burmese amber is described as Mirafloris burmitis gen. et sp. nov. The perianth is composed of two whorls of 3+3 distinctly vascularized tepals connected by an irregular network of veinlets. There are two whorls of 3+3 free stamens with latrorse dehiscence positioned opposite the tepals. A single 3-lobed style arises from the center of the flower. Perigonal nectaries are located at the base of the inner tepals. The oval-spherical pollen possess a single, longitudinal suture. The fossil shows affinities to the order Liliales and family Liliaceae. This is the first showy monocot flower described from Burmese amber and based on recent phylogenetic studies, may be one of the earliest records of a fossil member of the Liliales.
Nursing students' experiences of virtual simulation when using a video conferencing system - a mixed methods study.

Objectives There is limited knowledge about students' experiences with virtual simulation when using a video conferencing system. Therefore, the aim of this study was to explore how second-year undergraduate nursing students experienced learning through virtual simulations during the COVID-19 pandemic. Methods The study had an exploratory design with both quantitative and qualitative approaches. In total, 69 nursing students participated in two sessions of virtual simulation during spring 2020, and 33 students answered online questionnaires at session 1. To further explore students' experiences, one focus group interview and one individual interview were conducted using a video conferencing system after session 2. In addition, system information on use during both sessions was collected. Results Changes in the students' ratings of their experiences of virtual simulation with the Body Interact™ system were statistically significant. The virtual simulation helped them to bridge gaps in both the teaching and learning processes. Four important aspects of learning were identified: 1) learning by self-training, 2) learning from the software (Body Interact™), 3) learning from peers, and 4) learning from faculty. Conclusions We conclude that virtual simulation through a video conferencing system can be useful for student learning and feedback from both peers and faculty is important.
Mechanisms of Estrogen Receptor-Mediated Agonistic and Antagonistic Effects

Estrogenic compounds exert a vast variety of effects in wildlife and humans. Endogenous estrogens, like estradiol, regulate growth and development of their target tissues. Exogenous compounds with estrogenic and/or anti-estrogenic activities may disrupt these regulatory pathways. Environmental or industrial chemicals and phytoestrogens interfering with the hormonal or endocrine system are defined as endocrine disruptor. The estrogen receptor is the major regulatory unit within the estrogen-signaling pathway. Effects mediated by the estrogen receptor are not solely defined by its ligand by its ligand but are rather modulated by the tissue expression of the receptor, and the cellular and genetic environment. Endocrine disruptors are able to mimic estrogens by binding to the estrogen receptor and induce or inhibit estrogenic response. Phenolic compounds, pesticides, phytoestrogens, and synthetic estrogens like diethylstilbestrol are examples of endocrine disruptors or so-called endocrine active compounds. The potential of these chemicals to interfere with the endocrine system is primarily defined by their interaction with the estrogen receptor. However, the observed physiological effects are the result of a complex interplay between the estrogen receptor, its ligand, co-regulators, and other cell signaling pathways dependent on the target tissue.
Conventional Implicatures as Tacit Performatives

L'A. analyse les connecteurs discursifs tels que but, moreover et so, ainsi que certains modificateurs tels que even et still. A la difference de l'implicature conversationnelle, la contribution de ces connecteurs a la signification d'une phrase est determinee par leur sens conventionnel. Cependant, contrairement au sens conventionnel ordinaire, leur contribution n'affecte pas les conditions de verite de la phrase. L'A. propose une analyse de ces connecteurs en termes de performatifs. Cette analyse permet de montrer que ce qui est exprime comme non-vericonditionnel par les connecteurs discursifs fait partie de leur sens conventionnel
Democratization, Civil Society, and Social Capital in the Former Communist World: Four Empirical Tests of a Sui Generis Relationship

Do democratic performance and associational life go hand in hand in post-Communist countries? The answer is supported by experiments employing averages, standard deviations, and correlations. Could new democracies be possibly an aberration from the democratic norm? Or, when we refer to them, we have to relax some assumptions of the definition of democracy?
Structure-Activity Relationships of Curcumin and Its Analogs with Different Biological Activities†

ABSTRACT: Curcumin is a constituent of the yellow pigments isolated from Curcuma longa , which is commonly named turmeric and is the major ingredient of the spice curry. Curcumin possesses many bioactivities, such as anti-oxidant, anti-inflammatory, antiviral, antifungal, cancer chemopreventive, and cancer chemotherapeutic properties. This review paper is prefaced by a general introduction to the origin and bioactivity of curcumin, followed by general synthetic routes to curcumin and its analogs. The major part of this paper examines the current structure-activity relationship studies of curcumin and various curcumin analogs relating to different bioactivities and distinct biological targets of interest to scientists worldwide. Finally, the advantages of curcumin and related compounds, which have multiple biological targets in cancer treatment, are discussed.
Flexible Robotic Arm Control: Nonlinear Ultimate Boundedness and Linear Stabilization

We treat the question of control of an elastic robotic arm of two links. Ofcourse this approach can be extended to other elastic arms. A nonlinear ultimate boundedness controller (UBC) is synthesised such that in the closed-loop system, the joint angle tracking error is uniformly bounded, and tends to a certain small neighborhood of the origin. The controller includes a reference joint angle trajectory generator and integral error feedback. Although, the joint angles are controlled using the UBC, elastic modes are excited. A feedback stabilizer is designed for the linearized model including the UBC about the terminal state which is switched only in the vicinity of the equilibrium state for stabilization. Simulation results are presented to show that in the closed-loop system including the UBC and the stabilizer, accurate joint angle trajectory following and elastic mode stabilization are accomplished in the presence of uncertainty.
Negotiating Expectations in the Field: Gatekeepers, Research Fatigue and Cultural Biases

This paper considers disjunctures between my expectations and experience of doing dissertation fieldwork, which I conducted in Benin between the autumns of 1997 and 1998. The research examined the nature of women’s livelihood strategies and their associated outcomes in terms of material well-being. I now believe that my feminist worldview, and my growing exhaustion as the project progressed, resulted in my minimising the importance of key aspects of fieldwork in an African context. Specifically, I downplayed the importance of negotiating with male “gatekeepers” in gaining access to the women with whom I wanted to work. While most of the time I was able to manage this well enough, one day, in particular, stands out as a time when I handled these negotiations very poorly. This paper compares the experiences of that day with another much more productive and fruitful one to examine how and why expectations and experience can diverge. A consideration of some of the issues that resulted in the “lost day” might prove instructive for other researchers.
An efficient FIR filter architecture

An efficient architecture for finite impulse response (FIR) filters is described. By exploiting the reduced complexity made possible by the use of sparse powers-of-two coefficients, an FIR filter tap can be implemented with only 2B full adders and 2B (or 4B) latches, where B is the intermediate wordlength. Word and bit level parallelism allows high sampling rates, limited only by the full adder delay. This architecture allows the implementation of high sampling rate filters of significant length on a single field-programmable gate array (FPGA), as well implementation using more conventional VLSI techniques. >
Hall exponents of matrices, tournaments and their line digraphs

Let A be a square (0, 1)-matrix. Then A is a Hall matrix provided it has a nonzero permanent. The Hall exponent of A is the smallest positive integer k, if such exists, such that A k is a Hall matrix. The Hall exponent has received considerable attention, and we both review and expand on some of its properties. Viewing A as the adjacency matrix of a digraph, we prove several properties of the Hall exponents of line digraphs with some emphasis on line digraphs of tournament (matrices).
Textron's J-HPSSL 100 kW ThinZag® laser program

A new approach (ThinZag®) for scaling Nd∶YAG solid-state slab lasers to high power levels is described. Using an innovative optical configuration, thin slabs of solid-state gain material are immersed in a flowing cooling fluid, resulting in improved thermal management. Measurements at the ∼1 kW level were conducted to compare Nd∶YAG ceramic with Nd∶YAG crystalline slabs. The ceramic slabs demonstrated comparable laser output power relative to the more standard crystalline slabs and demonstrated better optical properties, which result in improved medium uniformity. Performance results from our nominally 5 kW and 15 kW modules are also presented. The 15 kW modules represent basic building blocks for the Joint High Power Solid State 100 kW Laser (J-HPSSL) currently being designed and developed by Textron Defense Systems. Recent measurements of three nominally 15 kW modules operating as a single aperture power oscillator where outputs to 30 kW with beam quality of 3.3 XDL were measured are also included. The reported powers were for operation below maximum pump rate of the device.
Technique for making a template for temporary restorations

A fast, accurate, and simple technique for fabricating custom templates used to construct customized acrylic resin temporary crowns and fixed partial dentures has been presented. Acrylic resins are used directly on the diagnostic cast to restore single tooth contours, secure pontics to the cast, and to contour edentulous areas. Duplicate casts and impressions are not needed. Acrylic resins prove superior to wax and other materials for constructing custom templates because they will not distort or melt under the heat and pressure of the thermal vacuum machine. Thus, the template is accurate and free of melted residue on the inner template surface.
Broadband micromachined J-band directional couplers

Advances in the MMIC technology have enabled development of millimeter-wave (MMW) to terahertz radar and communication systems [1-3]. The short wavelength at these frequency bands enables the integration of antennas and other passive components with MMIC transceiver modules to develop fully integrated communication links and radar front-ends. Directional couplers are essential components in the design of radar systems. They are typically used to divide local oscillator (LO) signal between the transmit and receive stages in order to maintain coherence in the system [1]. Waveguide directional couplers are of interest for sub-MMW and terahertz applications due to their low loss and simplicity of integration with other micromachined components.
Diamond microelectrodes for use in biological environments

Abstract The response sensitivity, precision and stability of a diamond microelectrode for the measurement of catecholamines is reported on and compared with a carbon fiber microelectrode. The comparison was made (i) before and after exposure of the bare microelectrode to the laboratory atmosphere and to biological tissue, and (ii) during the in vitro measurement of norepinephrine (NE)-release from a test animal’s mesenteric artery. The surface-sensitive redox system, Fe ( CN ) 6 - 3 / - 4 , was also used to probe the electrode response. The diamond microelectrode exhibited a low, stable and pH-independent background current over a wide potential range; good sensitivity and response reproducibility for NE; and resistance to deactivation and fouling during exposure to the laboratory atmosphere and biological tissue. In contrast, the carbon fiber microelectrode exhibited a pH-dependent background current response with evidence for electroactive surface carbon–oxygen functional groups, and deactivated irreversibly during laboratory air exposure and contact with tissue. The same diamond electrode properties that are responsible for the deactivation and fouling resistance (e.g., the non-polar, H-terminated surface with no extended π electron system) are also responsible for the more sluggish catecholamine electrode reaction kinetics (e.g., absence of molecular adsorption on the hydrogen-terminated sp3-bonded carbon surface). In addition, the bare diamond microelectrode provided excellent response characteristics during the in vitro measurement of NE-release from the mesenteric artery of a laboratory test animal. The results confirm that this new microelectrode is useful for sensitive, reproducible and stable electroanalytical measurements in complex biological environments.
Basis of Variable Sensitivities of GABAA Receptors to Ethanol

BACKGROUND The GABA(A) system is believed to be one of the crucial target sites for ethanol. However, in the literature, data using various preparations yielded controversial conclusions regarding the ethanol potency to modulate the activity of GABA(A) receptors. We have previously shown that the potency of n-alcohols to potentiate GABA-induced currents is correlated with their carbon chain length. This correlation was further compared among four cell types in an attempt to explain the variable potencies of ethanol to potentiate GABA responses. METHODS Whole-cell patch clamp experiments were performed to determine and compare the potencies of n-alcohols in potentiating GABA-induced currents in rat dorsal root ganglion (DRG) neurons, human embryonic kidney cells expressing the rat alpha1beta2gamma2S or alpha1beta2gamma2L subunits, and rat cortical neurons. RESULTS The GABA(A) receptors of the four cell types tested were all sensitive to n-alcohols, albeit with different potencies and efficacies. The effective concentration to increase GABA-induced currents to 125% of control (EC125) was correlated with the carbon chain length of n-alcohols, but slopes for this relationship are different among DRG neurons, the alpha1beta2gamma2S, and alpha1beta2gamma2L subunits. Thus, the potencies of lower alcohols such as ethanol differed among these cell types although higher alcohols such as n-octanol were almost equally potent. In cortical neurons, however, the relationship was shifted in the direction of longer carbon chains, indicating that their sensitivity was lower than those of the other three cell types. The ethanol EC125 values as obtained by experiments or those by extrapolation (in parenthesis) from the EC125-carbon chain length relationship were: 169 (103) mM for DRG neurons, 501 (333) mM for the alpha1beta2gamma2L subunits, 781 (674) mM for the alpha1beta2gamma2S subunits, and (1897) mM for cortical neurons. CONCLUSIONS It was concluded that the GABA(A) receptors of these four cell types were basically sensitive to n-alcohols including ethanol but the sensitivity curve was shifted to the lower side in the order of decreasing sensitivity of DRG neurons > alpha1beta2gamma2L > alpha1/beta2gamma2S > cortical neurons.
Enhancement of Respiration and Fermentation in Algae by Blue Light

In the dark, algae live on their reserve substances and respire very slowly. In this state a little blue light can stimulate their dark metabolism considerably. This regulatory effect may be the basis for several responses of plants to blue light.
MEDULLARY VAGAL EFFECTS OF D-LYSERGIC ACID DIETHYLAMIDE IN THE DECEREBRATE CAT.

DESPITE the fact that 2-brom-d-lysergic acid (BOL-148) and d-lysergic acid diethylamide (LSD-25) are both potent anti-metabolites of serotonin in vitro1,2, they do not exhibit similar behavioural or pharmacological effects in vivo. LSD-25 has been shown to produce bradycardia, a decrease in respiratory rate and hypotension in the pento-barbitalized, intact cat3. This is in contrast to the hypertension and tachycardia produced in spinal animals. The explanation advanced for these effects has been that in the intact animal the hypertension and tachycardia, due to peripheral vasoconstriction, are masked by more potent effects of LSD-25 on higher centres. BOL-148 was also shown to have no effect on heart rate and a weak nonspecific effect on blood pressure in the intact anaesthetized cat in doses up to 1 mg/kg (ref. 3). In the decerebrate cat, ergot alkaloids cause hypotension and bradycardia via medullary vagal centres4,5. Therefore, we attempted to study possible vagal effects of LSD-25 and BOL-148 in the decerebrate cat.
Performance Improvement of Abstractions Through Context Dependent Transformations

The use of abstractions enhances several aspects of a software system, especially its maintainability, reusability, and comprehensibility. However, it decreases the performance of the software. Context dependent transformations can effectively remove the performance loss of abstractions while preserving all their advantages. We state the conditions which the transformations should satisfy and develop four general transformation rules. Language mechanisms are proposed which permit the transformation directives to be embedded in the source code. This can be used to automate the transformations. It also facilitates an approach to incremental performance improvement.
Relaxation methods for problems with strictly convex costs and linear constraints

Consider the problem of minimizing a strictly convex possibly nondifferentiable and nonseparable cost subject to linear constraints. We propose a dual coordinate ascent method for this problem that uses inexact line search and either essentially cyclic or Gauss-Southwell order of coordinate relaxation. We show, under very weak conditions, that this method generates a sequence of primal vectors converging to the optimal primal solution. Under an additional regularity assumption, and assuming that the effective domain of the cost function is polyhedral, we show that a related sequence of dual vectors converges in cost to the optimal cost. If the constraint set has an interior point in the effective domain of the cost function, then this sequence of dual vectors is bounded and each of its limit points is an optimal dual solution. When the cost function is strongly convex, we show that the order of coordinate relaxation can become progressively more chaotic. These results significantly improve upon those obtained previously.
The distribution of the Theil U-statistic in bivariate normal populations

Abstract This note provides an exact finite sample distribution for the Theil (1966) U-statistic in correlated bivariate normal populations. The type II error rate using the F-distribution is shown to increase with the square of the correlation coefficient.
Fluoride-promoted cross-coupling reactions of alkenylsilanols. Elucidation of the mechanism through spectroscopic and kinetic analysis.

The mechanism of the palladium-catalyzed cross-coupling reaction of (E)-dimethyl-(1-heptenyl)silanol ((E)-1) and of (E)-diisopropyl-(1-heptenyl)silanol ((E)-2) with 2-iodothiophene has been investi...
On a generalization of the fundamental identity of Wald

Abstract : This paper extends the fundamental identity of Wald in the theory of sequential analysis to the case where the variables are Markovian rather than independent.
Insulin-like Growth Factor Binding Protein-4 Differentially Inhibits Growth Factor-induced Angiogenesis *

An in-depth understanding of the molecular and cellular complexity of angiogenesis continues to advance as new stimulators and inhibitors of blood vessel formation are uncovered. Gaining a more complete understanding of the response of blood vessels to both stimulatory and inhibitory molecules will likely contribute to more effective strategies to control pathological angiogenesis. Here, we provide evidence that endothelial cell interactions with structurally altered collagen type IV may suppress the expression of insulin-like growth factor binding protein-4 (IGFBP-4), a well documented inhibitor of the IGF-1/IGF-1R signaling axis. We report for the first time that IGFBP-4 differentially inhibits angiogenesis induced by distinct growth factor signaling pathways as IGFBP-4 inhibited FGF-2- and IGF-1-stimulated angiogenesis but failed to inhibit VEGF-induced angiogenesis. The resistance of VEGF-stimulated angiogenesis to IGFBP-4 inhibition appears to depend on sustained activation of p38 MAPK as blocking its activity restored the anti-angiogenic effects of IGFBP-4 on VEGF-induced blood vessel growth in vivo. These novel findings provide new insight into how blood vessels respond to endogenous inhibitors during angiogenesis stimulated by distinct growth factor signaling pathways.
The Structure of the Extracellular Domain of Triggering Receptor Expressed on Myeloid Cells Like Transcript-1 and Evidence for a Naturally Occurring Soluble Fragment

Triggering receptor expressed on myeloid cells like transcript-1 (TLT-1) is an abundant platelet-specific, type I transmembrane receptor. The extracellular fragment of TLT-1 consists of a single, immunoglobulin-like domain connected to the platelet cell membrane by a linker region called the stalk. Here we present evidence that a soluble fragment of the TLT-1 extracellular domain is found in serum of humans and mice and that an isoform of similar mass is released from platelets following activation with thrombin. We also report the crystal structure of the immunoglobulin domain of TLT-1 determined at the resolution of 1.19 A. The structure of TLT-1 is similar to other immunoglobulin-like variable domains, particularly those of triggering receptor expressed on myeloid cells-1 (TREM-1), the natural killer cell-activating receptor NKp44, and the polymeric immunoglobulin receptor. Particularly interesting is a 17-amino acid segment of TLT-1, homologous to a fragment of murine TREM-1, which, in turn, showed activity in blocking the TREM-1-mediated inflammatory responses in mice. Structural similarity to TREM-1 and polymeric immunoglobulin receptor, and evidence for a naturally occurring soluble fragment of the TLT-1 extracellular domain, suggest that this immunoglobulin-like domain autonomously plays an as yet unidentified, functional role.
Refinement of a Population-Based Bayesian Network for Fusion of Health Surveillance Data

The project was to refine a prototype population-based Bayes Network module for live implementation in the U.S. Department of Defense ESSENCE system to combine syndromic and clinical evidence sources to monitor health at hundreds of military care facilities. Evidence types included outpatient data records, laboratory tests, and filled prescription records. The multi-level approach included expanded data queries, data-sensitive algorithm selection, improved transformation of algorithm outputs to alert states, and hierarchical Bayesian Network training. Algorithmic and network thresholds were adjusted with stochastic optimization using 24 documented outbreak datasets.
Does fast magnetic reconnection exist

The main features of the Priest-Forbes (1986) and Priest-Lee (1990) models of magnetic reconnection in astrophysical plasmas are discussed, and the Priest-Lee model is generalized to include inflow pressure gradients and thus different regimes of reconnection. It is shown that different scaling results can be obtained depending on the boundary conditions. These results are compared to the ones observed in the numerical experiments of Biskamp (1986) and Lee and Fu (1986). It is concluded that numerical experiments with suitably designed boundary conditions are likely to exhibit fast reconnection, and that such reconnection is a common process in astrophysical and space plasmas.
Fatty acid composition of selected prosthecate bacteria

The cellular fatty acid composition of 14 strains of Caulobacter species and types, two species of Prosthecomicrobium, and two species of Asticcacaulis was determined by gas-liquid chromatography. In most of these bacteria, the major fatty acids were octadecenoic acid (C18:1), hexadecenoic acid (C16:1) and hexadecanoic acid (C16:0). Some cyclopropane and branched chain fatty acids were detected in addition to the straight chained acids. Hydroxytetradecanoic acid was an important component of P. enhydrum but significant amounts of hydroxy acids were not detected in other prosthecate bacteria examined.
Molecular imaging of alkylguanine-DNA alkyltransferase: further evaluation of radioiodinated derivatives of O6-benzylguanine.

Abstract Purpose An inverse correlation has been established between tumor levels of the DNA repair protein alkylguanine-DNA alkyltransferase (AGT) and a positive outcome after alkylator chemotherapy. Quantitative imaging of AGT could provide important information for patient-specific cancer treatment. Several radiolabeled analogues of O 6 -benzylguanine (BG), a potent AGT inactivator, have been developed and shown to be capable of labeling pure AGT protein. Herein, two of these analogues — O 6 -3-[*I]iodobenzylguanine ([*I]IBG) and O 6 -3-[*I]iodobenzyl-2′-deoxyguanosine ([*I]IBdG) — were further evaluated in two murine xenograft models. (AcO) 2 -[ 131 I]IBdG, a peracetylated derivative of IBdG, also was investigated as an alternative agent. Methods Several biodistribution studies of radioiodinated IBG and IBdG were performed in TE-671 human rhabdomyosarcoma and DAOY human medulloblastoma murine xenograft models. Mice were treated with BG or its nucleoside analogue dBG to deplete the tumor AGT content. The effect of unlabeled IBG and that of 7,8-benzoflavone (BF), an inhibitor of the cytochrome P-450 isozyme CYP1A2, on the tumor uptake of the tracers was determined. The uptake of (AcO) 2 -[ 131 I]IBdG along with that of [ 125 I]IBdG in DAOY cells in vitro was determined in the presence and absence of a nucleoside transporter inhibitor, dipyridamole. Results Pretreatment of mice either with BG or dBG failed to reduce tumor levels of [*I]IBG or [*I]IBdG even though such treatments completely depleted tumor AGT content. Treatment of mice with BF increased tumor uptake of [ 125 I]IBG by 56%; however, differentiation of tumors with and without AGT still was not possible. (AcO) 2 -[ 131 I]IBdG, a peracetylated derivative of IBdG, had a higher uptake in vitro in DAOY tumor cells. However, its uptake, like that of [ 125 I]IBdG, was blocked by dipyridamole. Conclusions Taken together, these results suggest that labeled agents that are more specific for cellular AGT and that are more metabolically stable are needed.
The production of high performance YBa2Cu3O7 using nitrogen dioxide

Energy Dispersive X-ray Spectroscopy (EDS) was used to show that the elemental homogeneity of YBa2Cu3O7 powders can be improved substantially by heating the powder in a nitrogen dioxide-containing atmosphere (e.g., 950°C), followed by annealing in oxygen at 950°C, and slow-cooling to room temperature. The improved homogeneity results in a substantially larger flux exclusion signal for the NO2-treated powder, as measured by both ac and dc techniques. The experimental results suggest a mechanism which involves the formation of a small amount of molten Ba(NO3)2, which acts as a flux that dissolves the constituents and reprecipitates them as high purity YBa2Cu3O7.
An Experimental Investigation on the Effect of Post-Injection Strategies on Combustion and Emissions in the Low-Temperature Diesel Combustion Regime

In order to meet future emissions regulations, new combustion concepts are being developed. Among them, the development of low-temperature diesel combustion systems has received considerable attention. Low NOx emissions are achieved through minimization of peak temperatures occurring during the combustion process. Concurrently, soot formation is inhibited due to a combination of low combustion temperatures and extensive fuel-air pre-mixing. In this study, the effect of late-cycle mixing enhancement by post injection strategies on combustion and engine-out emissions in the low-temperature combustion regime was investigated experimentally and numerically. The baseline operating condition considered for low-temperature combustion was 1500 rev/min, 3bar IMEP with 50% EGR rate, and extension to high loads was considered by means of post injection. Post injection strategies gave very favorable emission results in the low temperature combustion regime at all loads. With small second fuel injected amounts, better soot emissions were found. However, the determination of the dwell between the injections was found to be very important for the emissions. Since post injection leads to late-cycle mixing improvement, further reductions in soot emissions were achieved without deteriorating the NOx emissions. To explain these results, numerical analysis was also done using the KIVA-CHEMKIN code. The simulations show that optimal combustion requires that the post injection fuel avoid fuel rich regions formed from the main injection.Copyright © 2005 by ASME
Comparison of reactivity in a flow reactor and a single cylinder engine

Abstract The relative reactivity of 2:1:1 and 1:1:1 mixtures of n-decane:n-butylcyclohexane:n-butylbenzene and an average sample of JP-8 were evaluated in a single cylinder engine and compared to results obtained in a pressurized flow reactor. At compression ratios of 14:1, 15:1, and 16:1, inlet temperature of 500 K, inlet pressure of 0.1 MPa, equivalence ratio of 0.23, and engine speed of 800 RPM, the autoignition delay times were, from shortest to longest, the 2:1:1, followed by the 1:1:1, and then the JP-8. This order corresponded with recent results in a pressurized flow reactor, where the preignition oxidation chemistry was monitored at temperatures of 600–800 K, 0.8 MPa pressure, and an equivalence ratio of 0.30, and where the preignition reactivity from highest to lowest was the 2:1:1, followed by the 1:1:1, and the JP-8. This shows that the relative reactivity at low temperatures in the flow reactor tracks the autoignition tendencies in the engine for these particular fuels.
Carbon cycle. The roots of the matter.

Perhaps the most scientifically challenging phase of the terrestrial carbon cycle occurs below ground. Innovative experiments, carried out in northern Sweden, illustrate the huge influence of roots and associated fungi.
Dielectric properties of polymers at microwave frequencies: a review

Abstract A review of the dielectric loss spectra of polymers at microwave frequencies has been carried out. While the main focus of attention is the frequency range from 100 MHz to 100 GHz, loss spectra outside this region are also reviewed because variations in temperature can cause a shift of dielectric loss into or out of the microwave range. A large volume of data for low loss polymers (polyethylene, polypropylene and poly(tetrafluoroethylene)), which are used in the communications industry, was available for review. Other polymers, for which data were available and which have significant loss at microwave frequencies are: polystyrene, poly(vinylchloride), poly(vinylidene chloride), poly(vinylidene fluoride), poly(methyl-methacrylate), poly(methyl acrylate), poly(oxymethylene), poly(ethylene oxide), poly(propylene oxide), polyacetylene, and poly(sulphur nitride). Also, the microwave dielectric properties of engineering thermoplastics such as poly(phenylene oxide), polycarbonate and polysulphane have been reviewed. The origins of microwave dielectric loss in polymers are categorized as: (a) dipolar absorption dispersions in both crystalline and amorphous polymers; (b) dipolar losses due to impurities, additives or fillers in a polymer material; (c) microwave absorption in conducting polymers (polyacetylene and poly(sulphur nitride)) for which the current carriers are electrons; and (d) photon-phonon absorption spectra corresponding to the density of states in amorphous regions of a polymer material.
Electron spin resonance and instabilities in metal insulator semiconductor systems

Abstract Electron spin resonance measurements combined with electrical measurements provide an “atomic scale” understanding of trapping centers in amorphous insulating thin films and their interfaces with silicon.
“IF I TAKE MY PILLS I’ll GO HUNGRY”: THE CHOICE BETWEEN ECONOMIC SECURITY AND HIV/AIDS TREATMENT IN GRAHAMSTOWN, SOUTH AFRICA

Based on 14 months of ethnographic research in Grahamstown, South Africa, I argue that economic inequalities and structural barriers have created dire situations in which people living with HIV/AIDS (PLWHA) often are forced to choose between economic security and health security. While the rollout of antiretroviral treatment (ART) has been initiated in various stages throughout the country, the availability of treatment has created unanticipated and adverse responses. Many PLWHA who are too sick to work rely solely on social assistance grants as their only form of income. To qualify for what are locally known as “disability grants,” patients must demonstrate and maintain a CD4 count of 200 or below, which ironically, also is the marker to begin ART. This has created a complex dilemma as patients have begun to modify their adherence to and/or refuse ART to maintain low CD4 counts, in an effort to continue to receive their “disability grant,” thereby sustaining their economic and food security. Future HIV/AIDS programs must develop initiatives that do not conflict with patient treatment and prevention strategies but, rather, provide a holistic approach to economic and health security, particularly in resource-poor communities.
The Agenda Setting Function of the Mass Media At Three Levels of "Information Holding"

The objective of this study was to extend the theoretical concept of agenda setting to include three levels of peoples' information holding: (1) awareness of general issues; (2) awareness of proposed solutions; (3) specific knowledge about the proposals. A content analysis of three media and a survey were conducted to examine whether or not agenda setting is operative at Levels 2 and 3, since previous research has consistently shown agenda setting at Level 1. Concerning economic issues, high intercorrelations among media regarding economic content were found at Level 2. Agenda setting was found at both Levels 2 and 3, with newspapers primarily setting the agenda for all media users. In contrast to prior agenda setting studies which have found television to play a substantial role in setting the public agenda at Level 1, television was not round to be setting peoples' agenda at Levels 2 and 3.
Solid-phase microextraction with pH adjustment for the determination of aromatic acids and bases in water

Adjusting the pH of water samples before performing solid-phase microextraction (SPME) analysis can be used to selectively extract organic acids (at pH 2) and bases (at pH 12). Sorption behavior of test organics is predictable based on the acid dissociation constant in water. In general, polyacrylate (PA) and Carbowax-divinylbenzene (CW-DVB) show substantially higher fiber/water sorption coefficients (Kd values) than a polydimethylsiloxane (PDMS) coated fiber. Gas chromatography-flame ionization detection (GC-FID) detection limits with the CW-DVB sorbent are approximately 0.5 to 10 ng/ml in a 2-ml water sample for a variety of aromatic amines, phenols, and chlorinated phenols, and are approximately 1 to 50 ng/ml for the same solutes using the PA sorbent. However, the PA fiber is more selective (depending on the water pH) for the acid or base components than the CW-DVB fiber. With proper pH adjustment, the recovery of spiked aromatic amines and phenols from a surface wetlands water ranged from 73 to 118% of the known values, with a precision (R.S.D.) of approximately 5 to 20%. SPME quantitation of phenols in a coal gasification wastewater using a PA fiber also gave excellent agreement with conventional methylene chloride extraction, although continued use of a single fiber with this wastewater led to poorer precision.
Microbial community structure in sand on two olive ridley arribada nesting beaches, Playa La Flor, Nicaragua and Playa Nancite, Costa Rica

Microbial relative abundance, diversity and richness were assessed based on 16S rRNA gene-based TRF community analysis via terminal restriction fragment (TRF) analysis on two olive ridley turtle arribada nesting beaches in Central America, Playa La Flor in Nicaragua and Playa Nancite in Costa Rica. Arribada beaches have very high densities of egg clutches in small areas, and the sand contains numerous broken eggs due to turtles inadvertently disturbing previously laid clutches. The high organic content (broken eggs) in the sand causes microbial build up in clutches, which in return may affect hatching success. Phylotype relative abundance (fragment abundance) differed with nest density and distance from the water at both Playa Nancite and Playa La Flor. Higher relative abundance of certain bacterial species in high nest density areas may have contributed to lower hatching success. Bacterial diversity and richness increased with nest density and were higher in the zones closer to vegetation suggesting that bacterial diversity and richness may be important factors affecting hatching success of olive ridley eggs on these nesting beaches. To better conserve olive ridley sea turtles and manage egg harvest on arribada nesting beaches further studies should focus on identifying bacterial species that are pathogenic to turtle eggs and their effects on hatching success.
A molecular model for the genetic and phenotypic characteristics of the mouse lethal yellow (Ay) mutation

Abstract Lethal yellow (Ay) is a mutation at the mouse agouti locus in chromosome 2 that causes a number of dominant pleiotropic effects, including a completely yellow coat color, obesity, an insulin-resistant type II diabetic condition, and an increased propensity to develop a variety of spontaneous and induced tumors. Additionally, homozygosity for Ay results in preimplantation lethality, which terminates development by the blastocyst stage. The Ay mutation is the result of a 170-kb deletion that removes all but the promoter and noncoding first exon of another gene called Raly, which lies in the same transcriptional orientation as agouti and maps 280 kb proximal to the 3' end of the agouti gene. We present a model for the structure of the Ay allele that can explain the dominant pleiotropic effects associated with this mutation, as well as the recessive lethality, which is unrelated to the agouti gene.
Organization of programming languages for business information systems majors

The course CS8 “Organization of Programming Languages” of Curriculum '78 is presented in the context of a program for Business Information Systems at a small business college. The applicability of this course to the Information Systems curriculum is considered. It is asserted that the successful inclusion of this course suggests the desirability of including the other core computer science material, as defined in Curriculum '78, in a program for Information Systems.
SU(3)⊗SU(3), Symmetry Breaking, and Cabibbo Angle

Making use of bootstrap equations for symmetry-breaking vectors in $({3}^{*},3)\ensuremath{\bigoplus}(3,{3}^{*})$ and $(1,8)\ensuremath{\bigoplus}(8,1)$ representations of $\mathrm{SU}(3)\ensuremath{\bigotimes}\mathrm{SU}(3)$ with both octet and 27-plet electromagnetic and weak driving terms, and requiring partial conservation of vector current and the Cabibbo angle ${\ensuremath{\theta}}_{c}\ensuremath{\ne}0$, we obtain a solution of the form of Gell-Mann, Oakes, and Renner for semistrong breaking interaction. Knowing the deviation from $\mathrm{SU}(2)\ensuremath{\bigotimes}\mathrm{SU}(2)$ in their work, we get ${\ensuremath{\theta}}_{c}\ensuremath{\approx}0.22$. The nonleptonic $\ensuremath{\Delta}S=1$ interaction cannot be rotated away as it is in $(1,8)\ensuremath{\bigoplus}(8,1)$. Also the electromagnetic tadpole cannot be in $({3}^{*},3)\ensuremath{\bigoplus}(3,{3}^{*})$ but can be in $(1,8)\ensuremath{\bigoplus}(8,1)$.
Vascular Oxidant Stress Enhances Progression and Angiogenesis of Experimental Atheroma

Background— Although multiple pathological processes have been associated with oxidative stress, the causative relation between oxidative stress and arterial lesion progression remains unclear. Methods and Results— To test the effect of creating arterial wall oxidative stress, we compared progression of mouse carotid lesions induced by flow cessation in the wild-type (WT) versus transgenic mice (Tgp22vsmc), in which overexpression of p22phox, a critical component of NAD(P)H oxidase was targeted to smooth muscle cell (SMC). Compared with WT mice, arterial lesions grew significantly larger in Tgp22vsmc (P<0.001) and demonstrated elevated hydrogen peroxide (H2O2) and vascular endothelial growth factor (VEGF) levels at all time points examined (P<0.001, n=4 animals per time point), probably related to increased expression of hypoxia inducible factor (HIF)-1α via SMC oxidative stress in the Tgp22vsmc arteries, both basally (203±12% versus WT, P<0.001, n=3) and after lesion formation. Interestingly, Tgp22vsmc l...
Regulating the criminal justice snooper

Abstract Existing and anticipated restrictions on the conducting of social research present several opportunities and problems for criminal justice researchers. After reviewing those restrictions, the admittedly controversial techniques of covert and concealed research are used to show how restrictions may influence the direction criminal justice research follows in the coming years. A devil's advocate role is taken and covert and concealed research is championed in order to encourage academicians and practitioners to be both aware and wary of external restrictions on the conducting of social research.
When write is wrong: is all our professional literature on the same page?

This article looks at recent descriptions and analyses of the library and information science professional literature, primarily journal publications. Other professional literatures are also reviewed. Finally, a brief analysis of the content of six professional journals for articles published in 1993 is included.