cssi/SciSciGPT-SciSciNet huggingface dataset:
Dynamic Dopamine Modulation in the Basal Ganglia: A Neurocomputational Account of Cognitive Deficits in Medicated and Nonmedicated Parkinsonism

Dopamine (DA) depletion in the basal ganglia (BG) of Parkinson's patients gives rise to both frontal-like and implicit learning impairments. Dopaminergic medication alleviates some cognitive deficits but impairs those that depend on intact areas of the BG, apparently due to DA "overdose." These findings are difficult to accommodate with verbal theories of BG/DA function, owing to complexity of system dynamics: DA dynamically modulates function in the BG, which is itself a modulatory system. This article presents a neural network model that instantiates key biological properties and provides insight into the underlying role of DA in the BG during learning and execution of cognitive tasks. Specifically, the BG modulates the execution of "actions" (e.g., motor responses and working memory updating) being considered in different parts of the frontal cortex. Phasic changes in DA, which occur during error feedback, dynamically modulate the BG threshold for facilitating/suppressing a cortical command in response to particular stimuli. Reduced dynamic range of DA explains Parkinson and DA overdose deficits with a single underlying dysfunction, despite overall differences in raw DA levels. Simulated Parkinsonism and medication effects provide a theoretical basis for behavioral data in probabilistic classification and reversal tasks. The model also provides novel testable predictions for neuropsychological and pharmacological studies, and motivates further investigation of BG/DA interactions with the prefrontal cortex in working memory.
A class of congruences on a posemigroup

V-completions of partially ordered algebraic systems have been studied by many authors, see Jaffard [7]. In particular, Burgess and McFadden [3] considered V-completions of posemigroups by means of ideal systems.
Oculocutaneous Albinism Associated with Corneal Mesodermal Dysgenesis

A 48-year-old woman had tyrosine-negative oculocutaneous albinism and corneal mesodermal dysgenesis of the Axenfeld type. Results of chromosome analysis were normal, and no other family members showed the association of these two conditions. The rarity with which the association has been reported suggests that this combination of findings is probably coincidental.
The measurement of substance use among adolescents: When is the ‘bogus pipeline’ method needed?☆

The use of objective measures to assess cigarette smoking among adolescents has become commonplace in research studies in recent years. This trend is based on evidence that this so called pipeline methodology can increase the disclosure of socially proscribed behaviors in a setting where adolescents might otherwise feel pressure to deny that they smoke. This paper examines the effects of the pipeline methodology alone and in combination with procedures designed to ensure anonymity on the disclosure of tobacco, alcohol, and marijuana use by young adolescents. The data indicate that the pipeline procedures significantly increase disclosure of tobacco and marijuana use when students are promised confidentiality but not anonymity. However, when anonymity was assured, disclosure of cigarette use was just as high without the pipeline; for marijuana use, disclosure was higher without the pipeline. No effects were observed for alcohol disclosure. These data are interpreted for their implications for prospective and cross sectional studies.
A class of spectral density estimators

A class of spectral windows depending on one parameter is presented and shown to include many of the common windows. The mean square rate of convergence of the associated spectral density estimators are calculated in terms of this parameter for spectral densities which are locally Lipschitz continuous The class is shown to include certain data tapers and data windows corresponding to missing observations. This is true also for the kernels of (C−α) summability which provide means for estimating the spectral density when the covariance function is periodic.
TO WHOM IT MAY CONCERN: SENATORS‘ OPENING STATEMENTS AT SUPREME COURT CONFIRMATON HEARINGS

This article examines the opening statements made by members of the Senate Judiciary Committee at Supreme Court confirmation hearings. Its aim is to identify the audiences senators target in their opening statements and to examine the messages they send to these audiences. The article shifts the focus away from the outcome of Supreme Court nominations to the “nomination discourse” of confirmation proceedings. Although senators use their opening statements to send a variety of messages to multiple audiences, they tend to emphasize the themes of judicial philosophy, the questioning of nominees, and the Senate's role in the confirmation process.
Seasonal associations of phytoplankton and planktic foraminifera in an upwelling region and their contribution to the seafloor

Abstract Seasonal occurrences of both phytoplankton and zooplankton are closely associated with upwelling and stabilization in waters overlying the San Pedro Basin. This region is situated within the Southern California Bight and is affected by variations in the general southward flowing California Current and variable intrusion of oceanic waters. Increased northerly wind stress in spring and early summer results in upwelling of deeper, nutrient-rich waters into the photic zone. A seven month time-series sediment trap experiment revealed clear patterns in seasonal succession of both phytoplankton and planktic foraminifera. Several distinct high and low flux periods occurred over the study period, some of which can be related to rapid changes in the hydrographic environment caused by upwelling and subsequent surface water stratification. Factor analysis of relative abundances of combined phytoplankton and foraminiferal taxa defines seven assemblages reflecting seven stages of production which range in duration from two to five weeks. Factor scores describe phytoplankton and foraminiferal taxa indicative of specific production stages. Periods of high flux of the more abundant diatoms and planktic foraminifera also illustrate preferred production stages and compare well with percentage-based results. A comparison of the sediment trap assemblage with local sediment from an oxygenated portion of the basin suggests that long-term phytoplankton accumulation in this region is dominated by taxa associated with winter bloom and post-upwelling bloom production, implying that brief but massive episodic events overwhelm and dominate the annually averaged diatom species assemblage found in the sediments. Foraminifera, however, are modified by dissolution to the extent that the high production periods of late spring and during upwelling are poorly represented. Rather, species indicative of early spring and post-upwelling conditions dominate the planktic foraminiferal sedimentary assemblage.
The shape of human evolution: a geometric morphometrics perspective.

Study of morphological form is fundamental to the discipline of paleoanthropology. The size and shape of our ancestors' anatomical features have long been the focus of research on hominin systematics, phylogeny, functional morphology, ontogeny, variation, and evolutionary change. Early physical anthropologists relied on both qualitative descriptions of anatomical shape and linear measurements to assess variation among hominins. The seminal works of W. W. Howells1 and C. E. Oxnard2 helped to bring multivariate techniques to the forefront of physical anthropology. Howells' intention was the objective delineation of components of shape, which could then fuel further analyses and interpretations, as well as clarification of the ways that growth influences interindividual and interpopulational differences in shape. He expressed concern that previous comparisons of individual measurements did not capture the overall shape of the skull, which is “expressed by the relations between measurements.”1:3 Similarly, Oxnard recognized that a multivariate approach to the study of complex shapes allows “for such perturbations (e.g., variation and covariation)…that are difficult to evaluate by eye and impossible to reveal by measurement and simple analysis alone.”2:6 While multivariate methods offered clear advantages over univariate or bivariate representations of shape, the analysis of traditional morphometric measures such as linear distances, angles, and ratios, has limitations when it comes to quantifying the complex geometry of some anatomical structures. © 2012 Wiley Periodicals, Inc.
Transient Thermo-Elasto-Plastic Spherical Contact Analyses Considering Effects of Thermal Softening and Heat Partition

Frictional heating leads to the temperature rise, thermal expansion, and the thermo-elasto-plastic deformation, which may be responsible for the failure of components under contact and relative motion. This paper reports the development of a three-dimensional thermo-elasto-plastic contact model of counterformal bodies, which account for the transient heat transfer, temperature-dependent strain hardening behavior of materials, and realistic heat partition between surfaces. An extensive study on the contact of a sliding half-space over a stationary ball is conducted using this model.Copyright © 2008 by ASME
On the solid—liquid phase transition

The mechanism by which fluidity is brought about and maintained is discussed. It is suggested that fluidity arises when sufficient energy is coupled from acoustic modes to fluid modes. The coupling mechanism involves the nonlinearity in an essential way, so that the critical amplitude of the acoustic modes necessary to initiate fluidity is analogous to the critical “pump” amplitude in a laser necessary to initiate the laser action. The Lindemann law for melting expressed in terms of a critical amplitude ratio of the acoustic vibrations becomes a natural consequence of the model. Since the model describes primarily the development of fluidity within a single phase, additional discussion is given to show the relationship to the customary interpretation of melting as a first-order phase transition between two independent phases.
Preventing perinatal depression in low-income home visiting clients: a randomized controlled trial.

Objective To assess the efficacy of a 6-week cognitive-behavioral intervention in preventing the onset of perinatal depression and reducing depressive symptoms among low-income women in home visitation programs. Method Sixty-one women who were pregnant or who had a child less than 6 months of age and who were assessed as at risk for perinatal depression were randomized to a 6-week, group-based cognitive-behavioral intervention or usual home visiting services. Study participants were predominately African American, unmarried, and unemployed. Intervention sessions were led by a licensed clinical social worker or clinical psychologist. Home visitors provided 1-on-1 reinforcement of key intervention messages between group sessions. Depressive symptoms were measured with the Beck Depression Inventory-II (Beck, Steer, & Brown, 1996), and major depressive episodes were measured with the Maternal Mood Screener (MMS; Le & Munoz, 1998). Outcomes were assessed at baseline and at 1 week and 3 months postintervention. Results Repeated measures analysis of variance indicated that there was a significant Time × Condition interaction, F(2, 112) = 4.1, p = .02. At 3 months postintervention, 9 of 27 (33%) women receiving usual care reported levels of depressive symptoms that met clinical cutoff for depression on the MMS compared with 3 of 32 (9%) women in the intervention condition, χ²(1, N = 59) = 5.18, p Conclusion This study provides preliminary data on the efficacy of a cognitive-behavioral intervention to prevent perinatal depression among home visiting clients and suggests it is feasible to embed such an intervention in home visitation programs. A larger trial is warranted to attempt to replicate study findings.
Factors Supporting the Development and Utilization of an Outcome-Based Performance Measurement System in a Chemical Health Case Management Program

Abstract This paper describes the development and utilization of a performance measurement system installed in the case management program for chronic substance abusers who are committed for chemical dependency treatment in Hennepin County, Minnesota. The system (operational for over four years) produces quarterly management reports which display client characteristics at program entry as well as client outcomes achieved during and following the six-month commitment period. Institutionalization of the system within the program and the associated measurement of client characteristics and outcomes have helped to standardize case planning and to sensitize program staff to both client needs and the outcomes toward which staff and client efforts should be directed. Finally, the paper describes the special studies that have been generated from the performance measurement system's database. These include the development of caseload difficulty indices, and multivariate investigations of the relationship between c...
Calibrating Induction Electrodes Using Cathode Ray Beams

Electron beams, accelerated by cathode ray guns, were used to calibrate Zero Gradient Synchrotron (ZGS) beam induction electrodes, without dependence upon the accuracy of RF instruments. Apparatus and technique are described and discussed.
Diffusion of oxygen into still sea water

Bucket experiments were conducted to measure the rate of diffusion of oxygen into sea water, stripped of dissolved oxygen to about 1 mg/1, of "homogeneous" salinity of 26-30\permil and with a "stable" temperature gradient. In five successive tests, the water required about 60 hours, under calm laboratory conditions, to exceed 7 mg/1 at all depths in the bucket. Results of these tests indicated input of oxygen to be much more rapid than expected from molecular diffusion of the Fickian type, giving a diffusion coefficient of 6 \times 10^{-3} cm2sec-1compared to 2 \times 10^{-5} cm2sec-1. It is suggested that evaporation in the thin water layer at the air/ water boundary increases the salinity sufficiently to initiate the transfer of oxygen from the atmosphere into sea water by convective movements, even in the presence of a stable temperature gradient and in the absence of turbulence.
Males with Down's syndrome and nonneurogenic neurogenic bladder

ABSTRACTPurpose: We assessed the relationship of trisomy 21 with the most severe dysfunctional elimination syndrome, nonneurogenic neurogenic bladder or the Hinman-Allen syndrome.Materials and Methods: We retrospectively reviewed our experience with children with Down’s syndrome (trisomy 21) in a 10-year period and identified a subset who presented for the evaluation and treatment of urinary tract infections associated with severe disorders of urinary and fecal elimination.Results: Four males 9 months, 14 years, 18 years and 21 years old met the criteria for review. All patients underwent radiological and urodynamic evaluation, and were diagnosed with hydronephrosis and prostatic urethral dilatation with pelvic floor spasticity. Renal function studies showed a creatinine of 0.7 mg./dl. in the 9-month-old, 1.2 mg./dl. in the 14-year-old, 1.9 mg./dl. in the 18-year-old and 2.2 mg./dl. in the 21-year-old patient. Three patients underwent surgical treatment to protect the upper urinary tract, including bladde...
Plasticity of male mating behaviour in a marine bioluminescent ostracod in both time and space

Spectacular and abundant light displays consisting of highly complex and repeated vertical trains of secreted bioluminescent pulses are ejected into the water column above shallow grass beds in the western Caribbean about an hour after the sun sets if there is no moon present. These are male courtship displays produced by upwardly swimming male Photeros (formerly Vargula) annecohenae, small (
Early biochemical responses to photodynamic therapy monitored by NMR spectroscopy.

Studies directed at determining the biochemical events that lead to tumor cytotoxicity following photodynamic therapy, a promising new approach for treatment of neoplasia, have demonstrated that exposure of R3230AC mammary tumors to hematoporphyrin derivative or Photofrin II plus visible light caused marked impairment of mitochondrial enzymes functioning in oxidative phosphorylation and electron transport. 31P-NMR spectroscopy has now demonstrated that a rapid and striking decrease in NTP (ATP) levels, concomitant with a marked increase in P;, occurs in tumors shortly after photodynamic therapy. These effects appear to be fluence related. Possible changes in tumor vascularity, as detected by 2H-NMR measurements of the uptake of D20, were not observed under the conditions studied. Taken together with our earlier results, we conclude that the reduction in tumor ATP levels in situ, probably via inhibition of mitochondrial function, is a direct and early response of neoplastic tissue to porphyrin-induced photosensitization.
Alveolar Type II Epithelial Cell Dysfunction in Rat Experimental Hepatopulmonary Syndrome (HPS)

The hepatopulmonary syndrome (HPS) develops when pulmonary vasodilatation leads to abnormal gas exchange. However, in human HPS, restrictive ventilatory defects are also observed supporting that the alveolar epithelial compartment may also be affected. Alveolar type II epithelial cells (AT2) play a critical role in maintaining the alveolar compartment by producing four surfactant proteins (SPs, SP-A, SP-B, SP-C and SP-D) which also facilitate alveolar repair following injury. However, no studies have evaluated the alveolar epithelial compartment in experimental HPS. In this study, we evaluated the alveolar epithelial compartment and particularly AT2 cells in experimental HPS induced by common bile duct ligation (CBDL). We found a significant reduction in pulmonary SP production associated with increased apoptosis in AT2 cells after CBDL relative to controls. Lung morphology showed decreased mean alveolar chord length and lung volumes in CBDL animals that were not seen in control models supporting a selective reduction of alveolar airspace. Furthermore, we found that administration of TNF-α, the bile acid, chenodeoxycholic acid, and FXR nuclear receptor activation (GW4064) induced apoptosis and impaired SP-B and SP-C production in alveolar epithelial cells in vitro. These results imply that AT2 cell dysfunction occurs in experimental HPS and is associated with alterations in the alveolar epithelial compartment. Our findings support a novel contributing mechanism in experimental HPS that may be relevant to humans and a potential therapeutic target.
Sequential tests on a multinomial distribution and a Markov chain

Abstract In an earlier paper, a sequential test of the equality of probabilities in a multinomial distribution was proposed, and compared to fixed sample size tests in the special case of two categories. In the present paper, the test is generalized to testing any simple hypothesis about a multinomial distribution, and compared to fixed sample size tests when the number of categories is large. The method of construction of the test is used to construct tests with precisely the desired level of significance, for multinomial and other problems, including Markov chains.
Saccade latency reveals episodic representation of object color

While previous studies suggest that identity, but not color, plays a role in episodic object representation, such studies have typically used tasks in which only identity is relevant, raising the possibility that the results reflect task demands, rather than the general principles that underlie object representation. In the present study, participants viewed a preview display containing one (Experiments 1 and 2) or two (Experiment 3) letters, then viewed a target display containing a single letter, in either the same or a different location. Participants executed an immediate saccade to fixate the target; saccade latency served as the dependent variable. In all experiments, saccade latencies were longer to fixate a target appearing in its previewed location, consistent with a bias to attend to new objects rather than to objects for which episodic representations are being maintained in visual working memory. The results of Experiment 3 further demonstrate, however, that changing target color eliminates these latency differences. The results suggest that color and identity are part of episodic representation even when not task relevant and that examining biases in saccade execution may be a useful approach to studying episodic representation.
Posttranslational Modification of Mitochondrial Transcription Factor A in Impaired Mitochondria Biogenesis: Implications in Diabetic Retinopathy and Metabolic Memory Phenomenon

Mitochondrial transcription factor A (TFAM) is one of the key regulators of the transcription of mtDNA. In diabetes, despite increase in gene transcripts of TFAM, its protein levels in the mitochondria are decreased and mitochondria copy numbers become subnormal. The aim of this study is to investigate the mechanism(s) responsible for decreased mitochondrial TFAM in diabetes. Using retinal endothelial cells, we have investigated the effect of overexpression of cytosolic chaperone, Hsp70, and TFAM on glucose-induced decrease in mitochondrial TFAM levels, and the transcription of mtDNA-encoded genes, NADH dehydrogenase subunit 6 (ND6) and cytochrome b (Cytb). To investigate the role of posttranslational modifications in subnormal mitochondrial TFAM, ubiquitination of TFAM was assessed, and the results were confirmed in the retina from streptozotocin-induced diabetic rats. While overexpression of Hsp70 failed to prevent glucose-induced decrease in mitochondrial TFAM and transcripts of ND6 and Cytb, overexpression of TFAM ameliorated decrease in its mitochondrial protein levels and transcriptional activity. TFAM was ubiquitinated by high glucose, and PYR-41, an inhibitor of ubiquitination, prevented TFAM ubiquitination and restored the transcriptional activity. Similarly, TFAM was ubiquitinated in the retina from diabetic rats, and it continued to be modified after reinstitution of normal glycemia. Our results clearly imply that the ubiquitination of TFAM impedes its transport to the mitochondria resulting in subnormal mtDNA transcription and mitochondria dysfunction, and inhibition of ubiquitination restores mitochondrial homeostasis. Reversal of hyperglycemia does not provide any benefit to TFAM ubiquitination. Thus, strategies targeting posttranslational modification could provide an avenue to preserve mitochondrial homeostasis, and inhibit the development/progression of diabetic retinopathy.
Scattering From Surface RoughnessÃ¢â¬â?Implications On X-Ray Imaging

Results of an analysis of surface profile measurements by J. Bennett on a set of very smooth flat surfaces is presented. Visible scattering profiles are predicted and compared with measured scatter profiles. The predicted scatter profiles are integrated for compari-son with total integrated scatter measurements (TIS). Using the model analysis at X-ray wavelengths illustrates the impact of various surface profiles on X-ray imaging.© (1981) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Fifteen years' progress in the design of industrial diesel-electric switchers

The advent of a practical line of diesel-electric industrial switching locomotives waited upon the development of high-speed automotive-type diesel engines and suitable electric transmission and control equipment. When these were made available some 15 years ago, the forerunner of the present industrial switching locomotive was designed. The intervening years have witnessed steady progress in expansion, standardization, and refinement of this line of locomotives. Today it embraces units of varying size and power adequate to meet practically every type of industrial switching duty.
Short carbon fiber reinforced epoxy coating as a piezoresistive strain sensor for cement mortar

Abstract Epoxy containing 10 vol.% short carbon fibers and applied as a coating (0.2 mm thick) directly on cement mortar was found to be an effective piezoresistive strain sensor for tensile strain up to 0.042% and compressive strain down to −0.11%. Exceeding these strain limits caused damage in the coating. The strain sensitivity (reversible fractional increase in electrical resistance per unit strain) was 94–97 and 20–24 when the strain was contraction and expansion, respectively. The irreversible fractional increase in resistance per unit strain was 0.5–2.3 and 15–69 when the strain was contraction and expansion, respectively; it increased with increasing magnitude of strain. The resistance change was almost totally reversible when the strain was contraction, but was only partly reversible when the strain was expansion. The sensor in coating form was similar to that in bulk form in the electromechanical behavior.
Rapid and sensitive detection of protein biomarker using a portable fluorescence biosensor based on quantum dots and a lateral flow test strip.

A portable fluorescence biosensor with rapid and ultrasensitive response for protein biomarker has been built up with quantum dots and a lateral flow test strip. The superior signal brightness and high photostability of quantum dots are combined with the promising advantages of a lateral flow test strip and result in high sensitivity and selectivity and speed for protein detection. Nitrated ceruloplasmin, a significant biomarker for cardiovascular disease, lung cancer, and stress response to smoking, was used as model protein biomarker to demonstrate the good performances of this proposed quantum dot-based lateral flow test strip. Quantitative detection of nitrated ceruloplasmin was realized by recording the fluorescence intensity of quantum dots captured on the test line. Under optimal conditions, this portable fluorescence biosensor displays rapid responses for nitrated ceruloplasmin with the concentration as low as 1 ng/mL. Furthermore, the biosensor was successfully utilized for spiked human plasma sa...
A new ankylosaur (Dinosauria: Ankylosauria) from the Lower Cretaceous Cloverly Formation of central Montana

A cranium and other associated skeletal elements representing a new ankylosaurid dinosaur, Tatankacephalus cooneyorum gen. et sp. nov. possess several diagnostic features that indicate that this ne...
Neutrino opacities in nuclear matter

Abstract Neutrino–matter cross sections and interaction rates are central to the core-collapse supernova phenomenon and, very likely, to the viability of the explosion mechanism itself. In this paper, we describe the major neutrino scattering, absorption, and production processes that together influence the outcome of core collapse and the cooling of protoneutron stars. One focus is on energy redistribution and many-body physics, but our major goal is to provide a useful resource for those interested in supernova neutrino microphysics.
Sugar and structural change in the Cuban economy

Abstract Diversification of the economy away from sugar was high among the economic priorities of the Cuban revolutionary government in power since 1959. This essay explores whether sugar's role in the structure of the economy has in fact changed significantly in the last 25 years or so by examining three aspects of structural change: specialization in production, export concentration, and effects of changes in world sugar market prices on economic growth. The analysis suggests that policies of the revolutionary government have had a marginal impact in reducing sugar's role. Plans to increase sugar production and exports through the end of the century virtually assure that sugar will continue to play a predominant role in the economy.
CXCL16 REGULATES ANGIOTENSIN II-INDUCED INFLAMMATION AND PROTEINURIA

Hypertension is a major cause of chronic kidney disease. Recent studies have shown that inflammation plays a critical role in the pathogenesis and progression of hypertensive kidney disease. However, the signaling mechanisms underlying the induction of inflammation are poorly understood. We have found that CXCL16, a recently discovered chemokine, is induced in the kidney in a murine model of angiotensin II (Ang II)-induced hypertension. Therefore, we examined whether CXCL16 regulates inflammatory cell infiltration and renal injury using CXCL16 knockout (CXCL16-KO) mice. Wild-type (WT) and CXCL16-KO mice were treated with Ang II via subcutaneous osmotic minipumps at 1500 ng/kg/min for up to 4 weeks. To accelerate renal injury, all mice were subjected to unilateral nephrectomy and received 1% NaCl in drinking water. WT and CXCL16-KO mice had virtually identical blood pressure at baseline. Ang II treatment led to an increase in blood pressure that is similar between WT and CXCL16-KO mice. Immunohistochemical analysis showed that targeted disruption of CXCL16 inhibits infiltration of F4/80+ macrophages and CD3+ T cells in the kidney of Ang II treated mice compared with WT mice. Real time RT-PCR demonstrated that targeted disruption of CXCL16 reduced gene expression of inflammatory cytokines (IL-1β and TNF-α) in the kidney of Ang II treated mice. Histological analysis revealed that CXCL16 deficiency inhibited Ang II-induced renal injury. Furthermore, targeted deletion of CXCL16 reduced Ang II-induced proteinuria and podocyte loss. In Summary, our results indicate that CXCL16 plays a pivotal role in the development of renal injury and proteinuria through regulation of macrophage and T cell infiltration.
Oxidative metabolism of aflatoxin B1 by lipoxygenase purified from human term placenta and intrauterine conceptal tissues

Aflatoxin B1 (AFB1) is a teratogen in rodents and may be a human transplacental carcinogen. Although the presence of DNA adducts of AFB1 in the human placentas has been noted, the enzyme(s) responsible for the bioactivation was not identified. In this investigation, the linoleic acid (LA)-dependent cooxidation of AFB1 catalyzed by lipoxygenase (LO) purified by Con A affinity chromatography from the term placentas of nonsmokers was studied. HPLC chromatograms detected the presence of 5- and 15-HETE as the major metabolites and 12-HETE as a minor metabolite upon incubation of arachidonic acid (AA) with affinity purified human term placental LO. These results suggest that a mixture of LO isozymes is present in the affinity-purified enzyme preparations of term placentas. The optimal assay conditions to observe maximum rate of epoxidation included incubation of 250 microM AFB1 with 80 micrograms LO and 3.5 mM LA at pH 7.2. AFB1-8,9-tris-diol produced in the reaction was estimated spectrofluorimetrically. A Vmax of 432 +/- 26 pmol of AFB1-8,9-tris diol produced/min/mg protein and a Km of 77 microM for AFB1 were observed. The AFB1-8,9-tris-diol formation was dependent on the incubation time, concentration of enzyme protein, AFB1, and LA. LO catalyzed epoxidation of AFB1 was inhibited by NDGA, BHT, BHA, ETI, and gossypol. The evidence presented here clearly demonstrates that placental LO is capable of epoxidation of AFB1. Similar results were observed with LO preparations of human intrauterine conceptal tissues at 8-10 weeks of gestation.
A novel reconfigurable origami spring antenna

A foldable origami spring structure is presented in this paper, which can be expanded and collapsed. Based on this structure, one origami antenna is designed with operating frequency that can be changed based on its height. The return loss, far-field radiation pattern and peak gain of this antenna are presented.
NONLINEAR SEQUENCE-DEPENDENT STRUCTURE OF NIGRAL DOPAMINE NEURON INTERSPIKE INTERVAL FIRING PATTERNS

Firing patterns of 15 dopamine neurons in the rat substantia nigra were studied. These cells alternated between two firing modes, single-spike and bursting, which interwove to produce irregular, aperiodic interspike interval (ISI) patterns. When examined by linear autocorrelation analysis, these patterns appeared to reflect a primarily stochastic or random process. However, dynamical analysis revealed that the sequential behavior of a majority of these cells expressed "higher-dimensional" nonlinear deterministic structure. Dimensionality refers to the number of degrees of freedom or complexity of a time series. Bursting was statistically associated with some aspects of nonlinear ISI sequence dependence. Controlling for the effects of nonstationarity substantially increased overall predictability of ISI sequences. We hypothesize that the nonlinear deterministic structure of ISI firing patterns reflects the neuron's response to coordinated synaptic inputs emerging from neural circuit interactions.
Prokaryotic genomes: the emerging paradigm of genome-based microbiology.

Abstract Comparative analysis of the complete sequences of seven bacterial and three archaeal genomes leads to the first generalizations of emerging genome-based microbiology. Protein sequences are, generally, highly conserved, with ∼70% of the gene products in bacteria and archaea containing ancient conserved regions. In contrast, there is little conservation of genome organization, except for a few essential operons. The most striking conclusions derived by comparison of multiple genomes from phylogenetically distant species are that the number of universally conserved gene families is very small and that multiple events of horizontal gene transfer and genome fusion are major forces in evolution.
Matrix stiffness affects endocytic uptake of MK2-inhibitor peptides.

In this study, the role of substrate stiffness on the endocytic uptake of a cell-penetrating peptide was investigated. The cell-penetrating peptide, an inhibitor of mitogen-activated protein kinase activated protein kinase II (MK2), enters a primary mesothelial cell line predominantly through caveolae. Using tissue culture polystyrene and polyacrylamide gels of varying stiffness for cell culture, and flow cytometry quantification and enzyme-linked immunoassays (ELISA) for uptake assays, we showed that the amount of uptake of the peptide is increased on soft substrates. Further, peptide uptake per cell increased at lower cell density. The improved uptake seen on soft substrates in vitro better correlates with in vivo functional studies where 10–100 µM concentrations of the MK2 inhibitor cell penetrating peptide demonstrated functional activity in several disease models. Additional characterization showed actin polymerization did not affect uptake, while microtubule polymerization had a profound effect on uptake. This work demonstrates that cell culture substrate stiffness can play a role in endocytic uptake, and may be an important consideration to improve correlations between in vitro and in vivo drug efficacy.
Design and synthesis of molecules with switchable chirality via formation and cleavage of metal-ligand coordination bonds.

Here we describe a design and synthesis of organic molecules with switchable central chirality via simple cleavage and formation of metal−ligand coordination bonds, as a potentially useful and conceptually new approach to the design of a new generation of organic chiroptical molecular switches.
Xenogeneic cytotoxic T-cell clones recognize alloantigenic determinants on HLA-A2

Long-term murine cytotoxic T-cell clones arising in response to stimulation with human lymphoblastoid cells and reactive with the HLA-A2 antigen are characterized. These clones distinguish between HLA-A2 and 21 other serologically defined HLA-A and -B antigens. In addition, most clones discriminate between prototypical HLA-A2 antigens, expressed by the majority of HLA-A2-positive individuals, and variant HLA-A2 antigens, which are serologically identical with the prototype, but distinguishable by human cytotoxic T cells and by biochemical analysis. This discrimination is reflected as an inability to cause any significant lysis of variant HLA-A2-expressing target cells at effector-to-target ratios 10- to 100-fold greater than those giving 50% lysis of prototype HLA-A2-expressing cells. By screening a panel of serologically HLA-A2-positive cells, a new variant HLA-A2-expressing cell line has been defined. The recognition patterns of these xenogeneic clones are suggested to reflect recognition of alloantigenic polymorphic determinants. Based on the strong bias in the xenogeneic T-cell repertoire for such determinants, we propose a model for T-cell recognition of class I products of the major histocompatibility complex.
Single electron capture by multiply charged /sup 28/Si ions in atomic and molecular hydrogen

Cross sections for single electron capture by ${\mathrm{Si}}^{q+}$ ($2\ensuremath{\le}q\ensuremath{\le}9$) incident on atomic and molecular hydrogen have been measured in the relative-collision-velocity range (3.1-6.3)\ifmmode\times\else\texttimes\fi{}${10}^{8}$ cm/s. All measured cross sections decrease monotonically with relative velocity and scale roughly as ${q}^{N}$. The values of $N$ needed to fit the data range from \ensuremath{\sim}2 to \ensuremath{\sim}3 and increase with velocity. Cross sections averaged over incident charge states $q$ for molecular hydrogen are larger than for atomic hydrogen, becoming twice as large for relative velocities greater than 4\ifmmode\times\else\texttimes\fi{}${10}^{8}$ cm/s. For the limited cases where comparison was possible, we found the classical-trajectory Monte Carlo calculation to give a good account of the experimental results.
Electrochemiluminescent detection of metal cations using a ruthenium(II) bipyridyl complex containing a crown ether moiety.

The effects of metal ions on the electrochemiluminescence (ECL) properties of (bpy)2Ru(AZA-bpy) (bpy = 2,2‘-bipyridine; AZA-bpy = 4-(N-aza-18-crown-6-methyl-2,2‘-bipyridine) have been investigated. The electrochemistry, photophysics and ECL of Ru(bpy)32+ in the presence of Pb2+, Hg2+, Cu2+, and K+ are reported. The anodic oxidation of Ru(bpy)32+ produces ECL in the presence of tri-n-propylamine (TPrA) in 50:50 (v/v) CH3CN:H2O solution. Increases in ECL efficiency (photons generated per redox event) up to 20-fold that depend on both the concentration and nature of the metal ion have been observed, making this an interesting system for electrochemiluminescence metal ion sensing.
Integration of multiple components in polystyrene-based microfluidic devices part I: fabrication and characterization

In Part I of a two-part series, we describe a simple and inexpensive approach to fabricate polystyrene devices that is based upon melting polystyrene (from either a Petri dish or powder form) against PDMS molds or around electrode materials. The ability to incorporate microchannels in polystyrene and integrate the resulting device with standard laboratory equipment such as an optical plate reader for analyte readout and pipets for fluid propulsion is first described. A simple approach for sample and reagent delivery to the device channels using a standard, multi-channel micropipette and a PDMS-based injection block is detailed. Integration of the microfluidic device with these off-chip functions (sample delivery and readout) enables high-throughput screens and analyses. An approach to fabricate polystyrene-based devices with embedded electrodes is also demonstrated, thereby enabling the integration of microchip electrophoresis with electrochemical detection through the use of a palladium electrode (for a decoupler) and carbon-fiber bundle (for detection). The device was sealed against a PDMS-based microchannel and used for the electrophoretic separation and amperometric detection of dopamine, epinephrine, catechol, and 3,4-dihydroxyphenylacetic acid. Finally, these devices were compared against PDMS-based microchips in terms of their optical transparency and absorption of an anti-platelet drug, clopidogrel. Part I of this series lays the foundation for Part II, where these devices were utilized for various on-chip cellular analysis.
A New Methodology for Sensor Selection in Process Monitoring of Reconfigurable Machining Systems (RmSs)

This article outlines a new approach for selecting an appropriate monitoring system for any given machining system. Presented are the concepts of fault, sensor, signal processing and computing spaces and their generic characteristics. Study of their fundamental properties reveals that there are certain levels of uncertainty involved in describing them. This has led us to the adoption of fuzzy systems theory as a fundamental tool for development of the “Mapping Theory”. It is shown that based on the characteristics of the faults and the type of machining operations, it is possible to rank the sensors based on their characteristics and to come up with an appropriate multi-sensor monitoring system. Examples are provided to show the effectiveness of the approach.Copyright © 2002 by ASME
Unusual form of endobronchial Aspergillosis in a patient with cystic fibrosis.

The isolation of Aspergillus fumigatus from airway secretions from patients with cystic fibrosis (CF) is common and usually denotes asymptomatic colonization or allergic broncho-pulmonary aspergillosis (ABPA). A 12-year-old boy with CF acutely developed moderately severe symptoms of unremitting cough, fever, dyspnea, weight loss, and cyanosis. Chest radiographs demonstrated widespread unilateral infiltrates and volume loss. By bronchoscopy tenacious mucous plugs were seen occluding the left lower lobe bronchus. Cultures from sputum and sequential bronchoalveolar lavage grew Aspergillus fumigatus, but other significant criteria for diagnosing APBA were lacking. No improvement was seen with a 3 week course of systemic corticosteroid and antibiotic therapy. Treatment with amphotericin B and short-term mechanical ventilation resulted in rapid resolution of all symptoms. This form of endobronchial aspergillosis has not been described previously. Pediatr Pulmonol. 1993; 16:69–73. © 1993 Wiley-Liss, Inc.
Flavaspidic acid: A biochemical probe for the study of metabolic pathways in hepatocytes

Abstract Displacement of fatty acids or their CoA esters from the cytosolic fatty acid-binding-protein (FABP) by β-flavaspidic acid-N-methyl-glucaminate (flavaspidic acid) shifted the flow of lactate from the lipogenic to the gluconeogenic pathway in hepatocytes isolated from livers of fed rats. Analyses of radiolabel in products of 1 hour incubations utilizing 40 mM DL-sodium lactate (U- 14 C sodium lactate or 3 H 2 O) as substrate showed fatty acid synthesis to be depressed in the presence of 5 mM flavaspidic acid to levels ranging to 28% of control. Glucose synthesis, on the other hand, rose to a level 809% of control, a rate approximately equivalent to the maximal rate of gluconeogenesis found in hepatocytes from diabetic rats. The production of ketone bodies was not influenced by flavaspidic acid whereas CO 2 production decreased reflecting the diversion of the flow of lactate from the lipogenic to the gluconeogenic pathway. These results are presented in support of the hypothesis that unbound long-chain acyl CoA esters act as physiological effectors of the adenine nucleotide translocation and through this action, integrate lipogenic and gluconeogenic activities. Flavaspidic acid thus serves as a useful probe for studies of the role of long chain acyl CoA esters in the intracellular regulation of intermediary metabolism and of the modulation exerted by the FABP.
Fourier-transformed 13C NMR spectra of polyuridylic acid, uridine, and related nucleotides — The use of 31POC13C couplings for conformational analysis

Abstract The 13 C magnetic resonance spectra of polyuridylic acid, uridine, and related nucleotides in aqueous solution are reported. Earlier assignments of the 2′ and 3′ resonances are corrected. Conformational information is derived from the chemical shifts and from the magnitudes of 31 POC 13 C couplings. These couplings are shown to be particularly useful. The polynucleotide backbone is found to have distinct conformational preferences.
Some velocity profile effects in empty tubes

Abstract Several investigators have observed that macromolecular solutes deviate from the dispersion behavior predicted on the basis of a parabolic velocity profile. These experimental observations are discussed in the light of numerical computations on unsteady state mass and momentum-transport with concentration-dependent viscosity.
Risk Perception in an Interest Group Context: An Examination of the TMI Restart Issue1

Human response to environmental hazards and risks has been the subject of considerable research by social scientists. Work has traditionally focused on either individual response to the risks of an ongoing or future threat (hazards research), or group and organizational response to a specific disaster event (disaster research). As part of a larger investigation of the restart of the Unit 1 reactor at Three Mile Island (TMI), we examined the response of interest groups active in the restart issue to the continued threat of TMI and to future risks due to restart. After reviewing the restart issue in general, the paper examines the local dimensions of the restart issue from interest group perspectives. A method for defining appropriate issues at the community level is reviewed. We then discuss differences in the perceived local impacts of alternative decisions, and systems of beliefs associated with differing perceptions. Finally, we discuss the implications of interest group versus individual perceptions of local issues for decision making about TMI, in particular, and about technological hazards management, in general. Associated implications for determining socially acceptable risk levels are identified. Our research led us to three major conclusions: (1) in contrast to other types of hazards, interest groups are a critical unit of analysis for understanding how beliefs and behaviors form in response to the presence of technological hazards; (2) the divergence of positions between groups, even though they may have shared the same physical experience, is understandable if not always predictable, (3) the resolution of policy debates where risks are a major focus of the arguments should recognize the legitimacy of these divergent positions by allowing participation of the various interest groups in the decision process. Such participation helps ensure that the decision strategy is responsive to local concerns, thereby increasing the likelihood of acceptance of the ultimate decision and thus producing a publicly acceptable level of risk.
Improvements in the dual LCD-based stereo display (Invited Paper)

The benefits of stereo vision are numerous and quickly become apparent when attempting to perform simple tasks without the aid of stereo cues. The proliferation of remotely operated vehicles and indirect viewing applications has resulted in an increased need to see the operational environment in stereo. Several approaches to the display of stereo imagery have been demonstrated. Stereoscopic displays typically require the user to wear special headgear. Autostereoscopic displays require no headgear but typically have tight limitations on the position of the viewer's head. Previous papers have described a new type of stereoscopic display based on dual liquid crystal displays. The new display provides a stereo view without temporal or spatial multiplexing. Several prototype displays have been built and demonstrated to potential users with favorable reviews. With a successful proof-of-principle prototype completed, the effort is focusing on improvements to the image quality, consolidating the electronics, and packaging the display for use in rugged environments. The results of this effort should produce a rugged, compact, multiuse stereo display.