cssi/SciSciGPT-SciSciNet huggingface dataset:
Use of symmetry groups in sliding mode control of nonlinear distributed parameter systems

Sliding mode control theory is applied to a class of distributed parameter systems. The viability of using symmetry groups to aid in feedback control of such systems is discussed. A conjecture is presented that leads to the calculation of the control law. To support the conjecture, the method is applied to the control of a chemical reactor.
Genetic variation at the mtDNA ND-1 locus among North American wild and hatchery brown trout (Salmo trutta)

Despite extensive knowledge of mitochondrial DNA (mtDNA) variation in European brown trout (Salmo trutta) populations, little is known about their nucleotide sequence variation in North America. The objective of this study was to quantify single nucleotide polymorphisms (SNPs) at the ND-1 mtDNA locus of 62 brown trout from hatcheries in Michigan and Wisconsin as well as Michigan streams and Lake Michigan. We identified 25 SNPs that characterized nine distinct mtDNA haplotypes in the Wild Rose, Gilchrist and Seeforellen brown trout strains. Although most SNPs were represented by synonymous nucleotide substitutions, three individuals of the Seeforellen strain had non-synonymous nucleotide changes. MtDNA haplotypes identified in North American brown trout in this study showed nucleotide similarity at the ND-1 locus to brown trout from northern Europe.
Coronavirus N protein N-terminal domain (NTD) specifically binds the transcriptional regulatory sequence (TRS) and melts TRS-cTRS RNA duplexes

All coronaviruses (CoVs), including the causative agent of severe acute respiratory syndrome (SARS), encode a nucleocapsid (N) protein that harbors two independent RNA binding domains of known structure, but poorly characterized RNA binding properties. We show here that the N-terminal domain (NTD) of N protein from mouse hepatitis virus (MHV), a virus most closely related to SARS-CoV, employs aromatic amino acid-nucleobase stacking interactions with a triple adenosine motif to mediate high-affinity binding to single-stranded RNAs containing the transcriptional regulatory sequence (TRS) or its complement (cTRS). Stoichiometric NTD fully unwinds a TRS-cTRS duplex that mimics a transiently formed transcription intermediate in viral subgenomic RNA synthesis. Mutation of the solvent-exposed Y127, positioned on the β-platform surface of our 1.75 A structure, binds the TRS far less tightly and is severely crippled in its RNA unwinding activity. In contrast, the C-terminal domain (CTD) exhibits no RNA unwinding activity. Viruses harboring Y127A N mutation are strongly selected against and Y127A N does not support an accessory function in MHV replication. We propose that the helix melting activity of the coronavirus N protein NTD plays a critical accessory role in subgenomic RNA synthesis and other processes requiring RNA remodeling.
Cartographic Visualization: An Assessment and Epistemological Review*

Abstract This article examines the concept of cartographic visualization. The value of cartographic visualization as an essential component in the study of geographic phenomena is discussed. Ontological and epistemological perspectives are addressed, with examinations of positivist, realist, postmodern, feminist, and anarchist approaches to visualization. Critiques of cartographic visualization from social theorists and quantitative positivists are presented. The author asserts that cartographic visualization is not restricted to any one particular epistemological framework but may combine methods of knowledge production. For comprehensive analysis of spatial data, cartographic visualization must be included along with other qualitative and quantitative analysis. *I would like to thank three anonymous reviewers, as well as Zhi-Yong Yin and Jeffery McMichael, for their insightful comments and suggestions. I would also like to thank Andrew J. Herod and the “8910 Support Group” for the stimulating reading an...
A second look at Faster, Better, Cheaper

"Faster, Better, Cheaper" (FBC) was a systems development methodology used by NASA in the 1990s. While usually a deprecated practice, we find that, with certain caveats, it is a viable approach. To determine this we utilized a stochastic AI tool to determine the behavior of FBC for several case studies. In these case studies we compare results of using FBC with that of other optimization policies. In our tests, FBC is as advantageous a policy to use with projects as other policies, while avoiding their apparent downfalls.
Mechanical Buckling of Veins Under Internal Pressure

Venous tortuosity is associated with multiple disease states and is often thought to be a consequence of venous hypertension and chronic venous disease. However, the underlying mechanisms of vein tortuosity are unclear. We hypothesized that increased pressure causes vein buckling that leads to a tortuous appearance. The specific aim of this study was to determine the critical buckling pressure of veins. We determined the buckling pressure of porcine jugular veins and measured the mechanical properties of these veins. Our results showed that the veins buckle when the transmural pressure exceeds a critical pressure that is strongly related to the axial stretch ratio in the veins. The critical pressures of the eight veins tested were 14.2 ± 5.4 and 26.4 ± 9.0 mmHg at axial stretch ratio 1.5 and 1.7, respectively. In conclusion, veins buckle into a tortuous shape at high lumen pressures or reduced axial stretch ratios. Our results are useful in understanding the development of venous tortuosity associated with varicose veins, venous valvular insufficiency, diabetic retinopathy, and vein grafts.
On Characterizing Integral Stopping Time Functionals on Diffusions as Solutions to Boundary Value Problems

Abstract Let τ be the first exit time of a diffusion x(t) from a bounded domain Ω ⊂ ℝ n . This paper demonstrates that certain integral functionals ϕ↦E[ ϕ(t)dt | x(0) = x], ϕ:[0, ∞) → ℝ, may be characterized as solutions to elliptic boundary value problems. The result is established using probabilistic arguments together with results from the theory of partial differential equations. One particular functional, a stochastic analogue of the Fourier transform, is analyzed carefully. Its basic computational properties, including an inversion formula, are developed.
Beyond the street corner: The hidden diversity of high-poverty neighborhoods

The widely reported social pathologies of urban ghettos, barrios, and other slum areas have played a prominent role in the backlash against Aid to Families with Dependent Children and other social programs. The policy debate, however, has been fueled by a series of stereotypes about the characteristics of the residents of such neighborhoods. This article complements existing ethnographic research on high-poverty neighborhoods by examining social and economic data from the 1990 Census on all neighborhoods in U.S. metropolitan areas. High-poverty areas are found to contain a surprising amount of social and economic diversity. Although some residents clearly engage in “underclass” lifestyles, many of their neighbors are not public-assistance recipients and do participate in the labor market, albeit in lower-skill occupations and for fewer hours and lower wages. Other similarities and differences between high-poverty areas and other neighborhoods are explored, leading to a richer understanding of the nature o...
Productivity and OPC reticle inspectability using multibeam UV wavelength inspection

In order to extend the life of DUV lithography to the 130 nm design rule and below, optical proximity correction (OPC) and phase shift masks (PSM) have become increasingly common. The implementation of low k1 lithography in IC production requires inspection systems with smaller linewidth capability and higher sensitivity to obtain high yields in advanced reticle production. This paradigm presents greater inspection challenges for current UV tools. When inspections are run on advanced reticles on current tools, the number of false and nuisance defect detections are so high as to make inspecting these reticles unmanageable. The amount of de-sense required to bring false and nuisance detections down also causes real defects to be missed. The TeraStar SLF27 is the next generation reticle inspection tool from KLA-Tencor. The TeraStar addresses these problems with new algorithms that allow inspection of OPC features without desensing the detectors. Complementing this are triple-beam optics and the ability to run pattern and STARlightT inspections concurrently giving a net gain in the throughput and productivity of the tool. Here we present the first results from the use of the TeraStar in a production environment.
Geochemical and strontium isotopic characteristics of parental Aleutian arc magmas: evidence from the basaltic lavas of Atka

Eighteen flows from a basal stratigraphic sequence on the Aleutian Island of Atka were analyzed for major elements, trace elements and initial 87Sr/86Sr ratios. Petrographically, these lavas contain abundant plagioclase (24–45%) and lesser amounts of olivine (<7%), magnetite and clinopyroxene phenocrysts. Compositionally, the lavas are high-alumina (∼20wt%) basalts (48–51 wt% SiO2) with low TiO2 (<1%) and MgO (<5%). Within the section, compositional variations for all major elements are quite small. While MgO content correlates with olivine phenocryst contents, no such relationship exists between the other oxides and phenocryst content. These lavas are characterized by 8–10 ppm Rb, high Sr (610–669 ppm), 308–348 ppm Ba and very constant Zr (23–29 ppm) and Sc (23–29 ppm) abundances. Ni and Cr display extremely large compositional ranges, 12–118 ppm and 12–213 ppm, respectively. No correlation exists between trace element concentrations and phenocryst contents. Strontium isotopic ratios show a small but significant range (0.70314–0.70345) and are slightly elevated with respect to typical MORB. No systematic correlation between stratigraphic position and petrography or geochemistry is evident. REE abundances measured on six samples are LREE enriched ((La/ Yb)N = 2.20–2.81) and display similar chondrite normalized patterns. One sample has a slight positive Eu anomaly but the other lavas do not. Compared to other Aleutian basalts of similar silica content, these lavas are less LREE enriched and have lower overall abundances. The geochemical characteristics of these basalts suggest they represent true liquid compositions despite their highly porphyritic nature. Published phase relations indicate fractionation of a more MgO-rich magma could not have produced these lavas. The high Al2O3 and low MgO and compatible element abundances suggest a predominantly oceanic crustal source for parental high-alumina basalts.
Using a triad approach in the assessment of hazardous waste site leaching from a superfund site to an adjacent stream

A triad approach was used in the evaluation of sediment in the Wolf River adjacent to the North Hollywood Dump, a federally listed superfund site. Chemical analyses were done for 18 organochlorine pesticides, 21 polychlorinated biphenyl (PCB) congeners, and 10 metals. Sediment toxicity was evaluated with freshwater invertebrates, Chironomus tentans and Hyalella azteca. Benthic macroinvertebrate diversity and abundance were assessed with a family-level biotic index. Mean Al, Ba, Cd, Cu, Fe, Ni, Pb, and Zn concentrations were significantly higher in sediments collected in the spring. Both spring and fall sediments exhibited toxicity downstream from, adjacent to, and upstream from the dump, with toxicity significantly higher in fall sediments; however, a consistent trend was not observed. Toxicity was typically greater in the fall, and metal concentrations were typically higher in spring sediments, suggesting that metals were not responsible for the toxicity. Sediment-associated organochlorine pesticide and PCB congener concentrations were all below detectable limits, suggesting that these potential contaminants are not contributing to the observed toxicity. No differences were found in benthic macroinvertebrate community structure, which was composed of predominantly pollution-tolerant families, among seasons or river reaches, which appear to be limited by the physical characteristics of the river (e.g., substrate instability, low total organic carbon (<0.6%), and water velocity). Sediments in urban reaches of the Wolf River appear to be degraded; the North Hollywood Dump cannot be isolated as a source of toxicity in this study. In situ testing, sediment toxicity identification and evaluation testing, acid-volatile sulfide analyses, or artificial substrate work would be appropriate to follow.
A re-examination of the cloacal sacs and gland of the blind snake, Leptotyphlops dulcis (Reptilia: Leptotyphlopidae).

The cloacal sacs of Leptotyphlops dulcis are nonglandular, posterior evaginations of the cloaca. The median cloacal gland is tubuloalveolar. Similar unpaired cloacal glands as well as paired sacs are noted in certain colubrid snakes. Terminology applied to these cloacal derivatives is discussed, and a standardization of names is provided.
Intercellular dye migration and electrotonic coupling within neuronal networks of the crayfish brain

Intercellular dye migration (dye coupling) was studied in conjunction with functional indices of electrotonic coupling in 52 sensory interneurons of the brain and circumesophageal connectives of the crayfish,Procambarus clarkii. Dye-coupling was observed in 19 of the 52 successful injections. Dye-coupling between the symmetrically homologous medial giant neurons was observed in two out of three observations (Fig. 1). Dye-coupling was also observed between nongiant symmetrical homologues on five occasions and within clusters of morphologically similar cells on eight occasions. Seven of the preparations revealed coupling among three or more neurons (Figs. 4, 7; Table 1). In 18 of the 19 observations of dye-coupling, the dye was transferred exclusively from interneurons to other interneurons. The one exception was an interneuron to motoneuron transfer. In no instance was the dye transferred to a primary afferent. This is consistent with previous electrophysiological evidence indicating chemical synapses between primary afferents and interneurons. Dye-coupled cells also exhibited functional evidence consistent with the presence of electrotonic coupling among descending sensory interneurons: i) Two way excitatory transmission (Fig. 5); ii) Negligible transmission delay; iii) Synaptic potentials which follow presynaptic pulse trains at rates of up to 200 Hz and without attenuation (Fig. 6). It is concluded that a significant proportion of the descending interneurons are organized in electrotonically coupled networks of two to five morphologically similar neurons.
Discrimination among Spawning Concentrations of Lake Superior Lake Herring Based on Trace Element Profiles in Sagittae

Abstract Little is known about the stock structure of lake herring Coregonus artedi in Lake Superior, and recent increases in harvestable stock sizes has led to expanded exploitation in some areas. Research on marine teleosts has demonstrated that chemical differences in sagittal otoliths can be used for identification of fish stocks. We used plasma emission spectrophotometry to measure the concentrations of 10 trace elements in the sagittal otoliths from lake herring captured at eight spawning sites in Lake Superior and from Little Star Lake. an inland lake outside the Lake Superior basin. Discriminant function analysis indicated that elemental concentrations provided site-specific information but that considerable overlap existed among some locations, especially those in western Lake Superior. Correct classification rates varied from 12.0% to 86.1% and were generally higher for spawning locations from embayments in eastern Lake Superior and for the outgroup population from Little Star Lake. The results ...
Light narrowing of magnetic resonances in ensembles of nitrogen-vacancy centers in diamond

We investigate optically detected magnetic resonance signals from an ensemble of nitrogen-vacancy centers in diamond. The signals are measured for different light powers and microwave powers, and the contrast and linewidth of the magnetic-resonance signals are extracted. For a wide range of experimental settings of the microwave and light powers, the linewidth decreases with increasing light power, and more than a factor of 2 ``light narrowing'' is observed. Furthermore, we identify that spin-spin interaction between nitrogen-vacancy centers and substitutional nitrogen atoms in the diamond leads to changes in the line shape and the linewidth of the optically detected magnetic resonance signals. Finally, the importance of the light-narrowing effect for optimizing the sensitivity of magnetic-field measurements is discussed.
Experiences with predicting resource performance on-line in computational grid settings

In this paper, we describe methods for predicting the performance of Computational Grid resources (machines, networks, storage systems, etc.) using computationally inexpensive statistical techniques. The predictions generated in this manner are intended to support adaptive application scheduling in Grid settings, and on-line fault detection. Wedescribe a mixture-of-experts approach to non-parametric, univariate time-series forecasting, and detail the effectiveness of the approach using example data gathered from "production" (i.e. non-experimental) Computational Grid installations.
Emulsification of Hydrocarbon Fermentation Broth by Surfactants

In order to perform hydrocarbon fermentation satisfactorily, it was necessary to get the sample representing the real feature of the broth. However, Corynebacterium hydrocarboclastus S10B1, which could accumulate a good deal of l-glutamic acid, formed a coagulated mass of cells like pellet as they grew up, making the broth heterogeneous, To obtain homogeneous broth, addition of some kinds of surfactants was examined. It was made clear that addition of higher alcohol ethers of polyoxyethylene having H.L.B. value of about 15 was effective and emulsified broth could be obtained. Thus time course studies could be performed in hydrocarbon fermentation.
Twin fetuses in fetu.

Summary Description is given of twin “fetusesin fetu” which were successfully removed from a female infant on the fifth day of life. A brief summary of the literature is presented, including pathogenesis, descriptions, and treatments of these lesions. A fetus in fetu is a form of teratoma, and it should always be removed, along with its membranes, to insure a cure.
Diffusion of oxygen and carbon dioxide in thermally crystallized syndiotactic polystyrene

The diffusion, solubility, and permeability behavior of oxygen and carbon dioxide were studied in amorphous and semicrystalline syndiotactic polystyrene Is-PS). The crystallinity was induced in s-PS by crystallization from the melt and cold crystallization. Crystalline s-PS exhibited very different gas permeation behavior depending on the crystallization conditions. The behavior was attributed to the formation of different isomorphic crystalline forms in the solid-state structure of this polymer. The β crystalline form was virtually impermeable for the transport of oxygen and carbon dioxide. In contrast, the α crystalline form was highly permeable for the transport of oxygen and carbon dioxide. High gas permeability of the a crystals was attributed to the loose crystalline structure of this crystalline form containing nanochannels oriented parallel to the polymer chain direction. A model describing the diffusion and permeability of gas molecules in the composite permeation medium, consisting of the amorphous matrix and the dispersed crystalline phase with nanochannels, was proposed. Cold crystallization of s-PS led to the formation of a complex ordered phase and resulted in complex permeation behavior.
The emergence of second-tier auditors in the post-SOX era: An analysis of accounting conservatism ☆

Abstract The increased resource constraints experienced by Big-N audit firms as a result of the passage of Sarbanes-Oxley Act (SOX) contributed to the emergence of second-tier audit firms as viable alternatives to the Big N for public company clients, as suggested by the PCAOB. This study provides a comparative examination of an important property of accounting numbers, earnings conservatism, for clients of Big-N and second-tier audit firms in both the pre- and post-SOX periods. Our findings indicate that, while there is a general increase in conservatism in the post-SOX period, there is no significant difference in conservatism between clients of Big-N and second-tier auditors in either the pre- or post-SOX periods. In addition, the results show greater conservatism in the post-SOX period among clients of Big-N and second-tier firms relative to that of other (non-Big-N/non-second-tier) audit firms. Overall, the results lend support to the PCAOB’s recommendation concerning the use of second-tier auditors as a viable alternative to the Big-N and to the effectiveness of SOX in increasing reporting conservatism among clients of all auditors conducting public company audits in the post-SOX period.
Spinoza on self-consciousness and nationalism

In this essay the A. focus upon the concept of self-consciousness and nationalism as developed in Spinoza's physics, psychology of man, and extended into his treatment of political community
Synovium and the Innate Inflammatory Network in Osteoarthritis Progression

This review focuses on the recent advancements in the understanding of innate immunity in the pathogenesis of osteoarthritis, particularly with attention to the roles of damage-associated molecular patterns (DAMPs), pattern recognition receptors (PPRs), and complement in synovitis development and cartilage degradation. Endogenous molecular products derived from cellular stress and extracellular matrix disruption can function as DAMPs to induce inflammatory responses and pro-catabolic events in vitro and promote synovitis and cartilage degradation in vivo via PRRs. Some of the DAMPs and PRRs display various capacities in driving synovitis and/or cartilage degradation in different models of animal studies. New findings reveal that the inflammatory complement cascade plays a key in the pathogenesis of OA. Crosstalk between joint tissues such as synovium and cartilage communicated at the cellular level within the innate immune inflammatory network is implicated to play an important role in OA progression. Further studies on how the innate immune inflammatory network impacts the OA disease process at different stages of progression will lead to the development of new therapeutic strategies.
Capital Asset Pricing and Farm Real Estate

those of other investments. Accordingly, this paper uses the capital asset pricing model (CAPM) to estimate risk premiums required to hold farm real estate in a well-diversified market portfolio. Risk premiums are estimated for farm real estate at the national level and for ten farm production regions of the United States. CAPM results then are evaluated in light of farm real estate's unique characteristics.
Abstract 1786: Improved survival with gemcitabine and CTLA-4 blockade in a murine model of prostate cancer

Introduction: Immunotherapy with CTLA-4 blockade has resulted in dramatic responses in patients with advanced melanoma and prostate cancer. However, only 10-30% of patients have a response, therefore there is a need to increase the efficacy of CTLA-4 blockade. In this work we tested the hypothesis that combinatorial approaches incorporating tumor destruction with conventional chemotherapy and CTLA-4-blockade would synergize to significantly increase anti-tumor activity in vivo. Experimental Procedure: Mice with a transplantable prostate tumor (TRAMPC2) were treated with 5 doses of gemcitabine alone, or followed by immunotherapy with CTLA-4 blockade. Control mice were treated with isotype antibody. Tumor growth was measured by calipers and mice were sacrificed when tumors reached 15mm. Progression was followed over time and CD8 T cell responses to the tumor specific antigen SPAS were examined by tetramer staining and functional assays ex vivo. Data: Mice treated with the combination gemcitabine and α-CTLA-4 had improved survival over mice treated with gemcitabine alone. The majority of mice treated with control Hamster Ig or CTLA-4 blockade died (median survival 59 days for both groups). The median survival of mice treated with gemcitabine was 72 days with 50% having long-term survival. The addition of α-CTLA-4 to gemcitabine treatment increased median survival to > 125 days with 65% of mice with long term survival (p Conclusion: Combination chemo- and immunotherapy with gemcitabine and α-CTLA-4 improves survival. This is associated with an accumulation of CD8 cells that are tumor specific. Depletion of CD8 cells reduces the efficacy of this treatment. This study supports further investigation into the additive effects of chemotherapy with CTLA-4 blockade. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1786. doi:10.1158/1538-7445.AM2011-1786
Quotient Rings of Polynomial Rings.

Let R be a commutative ring with identity. The multiplicatively closed sets U2={f∈R[X]: c(f)−1=R}, (U2)={f∈U2: f is regular} and S={f∈R[X]: c(f)=R} are studied. By considering various equalities between these sets, many characterizations of Noetherian rings are found. In particular, a Noetherian ring R has depth ≤1 if and only if S=(U2): and each maximal ideal of a Noetherian ring is regular if and only if U2=(U2).
The effects of induced mood on expectancy-based illusory correlations

Abstract Two studies investigated the impact of induced mood states on expectancy-based illusory correlations about occupational groups. We expected incongruency between the valence of induced mood and the valence of presented stimulus information to increase difficulty of processing, which was in turn expected to increase the magnitude of illusory correlations. In the first study, subjects in whom a positive, negative, or neutral mood had been induced read sentences that described members of four occupational groups with stereotypic and unrelated positive or negative attributes. Illusory correlations in subjects' judgments (overestimations of the frequency with which stereotypic, relative to unrelated, attributes had described each occupational group) were stronger when the valence of the attributes was incongruent with mood state. In Experiment 2, subjects took longer to read sentences containing stereotype-unrelated attributes than to read sentences containing stereotype-confirming material when the valence of the descriptive attributes was incongruent with subjects' mood state. Implications of these findings for theoretical accounts of the effects of mood on stereotyping are discussed.
Triton's Geyser-Like Plumes: Discovery and Basic Characterization

One model for the mechanism driving the plumes of the four active geyser-like eruptions observed by Voyager 2 on Triton is a heating up of nitrogen ice in a subsurface greenhouse environment, where nitrogen gas pressurized by solar heating explosively vents to the surface carrying clouds of ice and dark particles into the atmosphere. A temperature increase of less than 4 K above the ambient surface value of 38 + or - 3 K suffices to drive the plumes to 8-km altitude. Each eruption may last a year or more, over the course of which 0.1 cu km of ice is sublimed.
Increased cerebrospinal fluid F2-isoprostanes are associated with aging and latent Alzheimer's disease as identified by biomarkers

Alzheimer’s disease (AD) is a common age-related chronic illness with latent, prodrome, and fully symptomatic dementia stages. Increased free radical injury to regions of brain is one feature of prodrome and dementia stages of AD; however, it also is associated with advancing age. This raises the possibility that age-related free radical injury to brain might be caused in part or in full by latent AD. We quantified free radical injury in the central nervous system with cerebrospinal fluid (CSF) F2-isoprostanes (IsoPs) in 421 clinically normal individuals and observed a significant increase over the adult human lifespan (P < 0.001). Using CSF amyloid (A) β42 and tau, we defined normality using results from 28 clinically normal individuals <50 years old, and then stratified 74 clinically normal subjects ≥60 years into those with CSF that had normal CSF Aβ42 and tau (n = 37); abnormal CSF Aβ42 and tau, the biomarker signature of AD (n = 24); decreased Aβ42 only (n = 4); or increased tau only (n = 9). Increased CSF F2-IsoPs were present in clinically normal subjects with the biomarker signature of AD (P < 0.05) and those subjects with increased CSF tau (P < 0.001). Finally, we analyzed the relationship between age and CSF F2-IsoPs for those clinically normal adults with normal CSF (n = 37) and those with abnormal CSF Aβ42 and/or tau (n = 37); only those with normal CSF demonstrated a significant increase with age (P < 0.01). These results show that CSF F2-IsoPs increased across the human lifespan and that this age-related increase in free radical injury to brain persisted after culling those with laboratory evidence of latent AD.
Aligned carbon nanotube sheet high efficiency particulate air filters

Abstract Aerosol filters, made with conventional micro-fiber fabrics, are designed to efficiently capture small particles from the air. Filters constructed of nano-fiber fabric structures provide even greater filtration efficiency than conventional micro-fiber fabrics due to their higher surface area and smaller pore size. Carbon nanotubes (CNTs) are very small diameter fibers that have the potential to be integrated into filters to further increase particle capture efficiency. In this study, CNT sheets, drawn from millimeter tall CNT arrays, were integrated between traditional micro-fiber fabrics to produce aerosol filters. The filtration performance of the novel filters showed that when the number of CNTs layers increased, the filtration efficiency increased dramatically, while the pressure drop also increased. In order to meet high efficiency particulate air (HEPA) filter requirements with a reasonable pressure drop, CNTs were laid in a cross-plied structure within the filter. The results demonstrated that the three layer cross-ply structure provided 99.98% filtration efficiency at 0.3 μm particle size at a 10 cm/s face velocity, making it a viable method for producing low basis weight HEPA filters utilizing CNTs as the main filtration component.
Antigen-specific proteolysis by hybrid antibodies containing promiscuous proteolytic light chains paired with an antigen-binding heavy chain.

The antigen recognition site of antibodies consists of the heavy and light chain variable domains (VL and VH domains). VL domains catalyze peptide bond hydrolysis independent of VH domains (Mei, S., Mody, B., Eklund, S. H., and Paul, S. (1991) J. Biol. Chem. 266, 15571–15574). VH domains bind antigens noncovalently independent of VL domains (Ward, E. S., Gussow, D., Griffiths, A. D., Jones, P. T., and Winter, G. (1989) Nature 341, 544–546). We describe specific hydrolysis of fusion proteins of the hepatitis C virus E2 protein with glutathione S-transferase (GST-E2) or FLAG peptide (FLAG-E2) by antibodies containing the VH domain of an anti-E2 IgG paired with promiscuously catalytic VL domains. The hybrid IgG hydrolyzed the E2 fusion proteins more rapidly than the unpaired light chain. An active site-directed inhibitor of serine proteases inhibited the proteolytic activity of the hybrid IgG, indicating a serine protease mechanism. The hybrid IgG displayed noncovalent E2 binding in enzyme-linked immunosorbent assay tests. Immunoblotting studies suggested hydrolysis of FLAG-E2 at a bond within E2 located ∼11 kDa from the N terminus. GST-E2 was hydrolyzed by the hybrid IgG at bonds in the GST tag. The differing cleavage pattern of FLAG-E2 and GST-E2 can be explained by the split-site model of catalysis, in which conformational differences in the E2 fusion protein substrates position alternate peptide bonds in register with the antibody catalytic subsite despite a common noncovalent binding mechanism. These studies provide proof-of-principle that the catalytic activity of a light chain can be rendered antigen-specific by pairing with a noncovalently binding heavy chain subunit.
Performance standards improve American Board of Surgery In-Training Examination scores.

Abstract Purpose Although several studies have evaluated factors affecting American Board of Surgery In-Training Examination (ABSITE) performance, none has examined the impact of setting a minimally acceptable standard. It was hypothesized that establishing such a criterion would improve ABSITE scores. Methods An expectation for residents to score at the 35th percentile or higher was established in 1996. The proportion of test scores above or below the 35th and 50th percentiles for the time periods before and after institution of the standard were compared using Fisher’s exact test. The subsequent performance of residents scoring below the 35th percentile was analyzed for the 2 time periods. Results After the institution of the standard, the proportion of scores below the 35th percentile decreased from 46.7% to 21.9% (p = 0.0005). Similarly, the proportion of scores at or above the national average increased from 42.1% to 65.6% (p = 0.0005). After establishing the standard, fewer residents continued to have scores below the criterion in subsequent years. Conclusions Establishing a performance criterion improved ABSITE scores. The decision to institute a standard must be individualized for each program. The rationale for the standard and a plan to assist residents failing to achieve the benchmark must be communicated.
Decoupling Sparsity and Smoothness in the Discrete Hierarchical Dirichlet Process

We present a nonparametric hierarchical Bayesian model of document collections that decouples sparsity and smoothness in the component distributions (i.e., the "topics"). In the sparse topic model (sparseTM), each topic is represented by a bank of selector variables that determine which terms appear in the topic. Thus each topic is associated with a subset of the vocabulary, and topic smoothness is modeled on this subset. We develop an efficient Gibbs sampler for the sparseTM that includes a general-purpose method for sampling from a Dirichlet mixture with a combinatorial number of components. We demonstrate the sparseTM on four real-world datasets. Compared to traditional approaches, the empirical results will show that sparseTMs give better predictive performance with simpler inferred models.
Representation in Congressional Campaigns: Evidence for Discounting/Directional Voting in U.S. Senate Elections

Several recent studies suggest that voters may prefer candidates who propose policies that are similar to, but more extreme than, the voters’ sincere policy preferences. This may arise either because voters vote directionally based on the direction and intensity of candidates’ proposals or, alternatively, because voters recognize that elected officials face obstacles to implementing their policy agenda and therefore discount the candidates’ policy promises. Using data from the Pooled Senate Election Study, we evaluate the discounting/directional hypothesis versus the alternative proximity hypothesis, by conducting individual-level and aggregate-level analyses of voting in 95 Senate races held in 1988–90–92. Our results support the discounting/directional hypothesis, that voters reward candidates when they present distinctly noncentrist positions on the side of the issue (liberal or conservative) favored by their constituency. These findings have important implications for understanding voting behavior, po...
A 7.27 GHz ${\rm Q}$ -Enhanced Low Noise Amplifier RFIC With 70 dB Image Rejection Ratio

This letter presents a low noise amplifier (LNA) RFIC with notch filter implemented in a 0.13 μm SiGe BiCMOS technology. The LNA/filter combination utilizes Q-enhanced techniques to achieve a high gain and high image rejection ratio (IRR) simultaneously. The amplifier operates at 7.27 GHz and achieves 22.5 dB gain with an IIR of 70 dB. The measured noise figure and IIP3 of the LNA are better than 5.1 dB and -13 dBm, respectively. The LNA dissipates 21 mW power with a 1.7 V supply.
Surgical treatment of choledochal cysts

Biliary cystic disease is uncommon in Asia and very rare in Europe and the Americas. Patients with biliary cysts may present as infants, children, or adults. When patients present as adults, they are more likely to have stones in the gallbladder, common duct, or intrahepatic ducts and to present with biliary colic, acute cholecystitis, cholangitis, or gallstone pancreatitis. With increasing age at presentation, the risks of intrahepatic strictures and stones, segmented hepatic atrophy/hypertrophy, secondary biliary cirrhosis, portal hypertension, and biliary malignancy all increase significantly. Factors to be considered when performing surgery on patients with biliary cystic disease include: (1) age, (2) presenting symptoms, (3) cyst type, (4) associated biliary stones, (5) prior biliary surgery, (6) intrahepatic strictures, (7) hepatic atrophy/hypertrophy, (8) biliary cirrhosis, (9) portal hypertension, and (10) associated biliary malignancy. In general, regardless of age, presenting symptoms, biliary stones, prior surgery or other secondary problems, surgery should include cholecystectomy and excision of extrahepatic cyst(s). With respect to the distal bile duct, the surgical principle should be excision of a portion of the intrapancreatic bile duct with care to not injure the pancreatic duct or a long common channel. Resection of the pancreatic head should be reserved for patients with an established malignancy. With respect to the intrahepatic ducts, surgery should be individualized depending on whether (1) both lobes are involved, (2) strictures and stones are present, (3) cirrhosis has developed, or (4) an associated malignancy is localized or metastatic. When the liver is not cirrhotic, hepatic parenchyma should be preserved even when strictures and stones are present. If cirrhosis is advanced, hepatic transplantation may be indicated, but this sequence of events is unusual. If a malignancy has developed, oncologic principles should be followed. Whenever possible, resection of a localized tumor including adjacent hepatic parenchyma and regional lymph nodes should be performed.
Extensively Drug-Resistant Tuberculosis

It has been many years since a single agent was recommended for treatment of active tuberculosis (TB). Despite this, there is strong evidence that multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) are present in all regions of the world, and there is also evidence that the incidence of drug-resistant forms of TB is increasing. Results of the survey of antituberculosis drug resistance in the world discussed in detail were published in a landmark article in the New England Journal of Medicine and in a longer, more-detailed monograph issued directly by the World Health Organization (WHO). The survey reported that MDR-TB cases were found in all regions of the globe and in many regions at levels far higher than had been expected. The major problem in diagnosis of XDR-TB is the lack of culture facilities for sputum in much of the world, particularly in high-burden countries. Treatment of MDR-TB and XDR-TB is largely empirical, as no controlled clinical trials of treatment regimens have been conducted. Fueled by the human immunodeficiency virus (HIV) epidemic, MDR-TB and XDR-TB have the potential to spread rapidly and cause a great deal of morbidity and mortality. Aggressive drug therapy, sometimes combined with surgery, can achieve good outcomes in a majority of cases, but these approaches are available mostly in resource-rich nations, with limited availability in countries where the disease is most common.
Ordinal Judgments in the Rat: An Understanding of Longer and Shorter for Suprasecond, but Not Subsecond, Durations

An emerging corpus of clinical and neuroimaging data suggests that subsecond and suprasecond durations are represented via 2 distinct mechanisms in humans; however, surprisingly, behavioral data to this effect are lacking. In our first experiment, we perform the first systematic exploration of subsecond and suprasecond timing within the same session in nonhuman subjects. Rats were trained to judge the relative duration of 2 sequential stimuli, responding on one lever if the first stimulus was longer or on a second lever if the converse was true. Our data provide strong evidence of an abstract understanding of longer and shorter for durations in the suprasecond range, whereas responding was at chance levels for durations in the subsecond range. Data from a second experiment reveal that this pattern is not due to an inability to time subsecond signals, as rats respond systematically in subsecond and suprasecond bisection tasks. Together, our results provide the first clear behavioral evidence of a discontinuity in the mental time line. These data from rats are discussed in light of similar findings of a discontinuity in the mental number line in human infants.
On Optimal Harvesting in Stochastic Environments: Optimal Policies in a Relaxed Model

AbstractThis paper examines the objective of optimally harvesting a single species in astochastic environment. This problem has previously been analyzed in Alvarez (2000)using dynamic programming techniques and, due to the natural payoﬀ structure ofthe price rate function (the price decreases as the population increases), no optimalharvesting policy exists. This paper establishes a relaxed formulation of the harvestingmodel in such a manner that existence of an optimal relaxed harvesting policy can notonly be proven but also identiﬁed. The analysis imbeds the harvesting problem in aninﬁnite-dimensional linear program over a space of occupation measures in which theinitial position enters as a parameter and then analyzes an auxiliary problem havingfewer constraints. In this manner upper bounds are determined for the optimal value(with the given initial position); these bounds depend on the relation of the initialpopulation size to a speciﬁc target size. The more interesting case occurs when theinitial population exceeds this target size; a new argument is required to obtain a sharpupper bound. Though the initial population size only enters as a parameter, the valueis determined in a closed-form functional expression of this parameter.Key Words. Singular stochastic control, linear programming, relaxed control.AMS subject classiﬁcation. 93E20, 60J60.
Development of a constrained motion algorithm for the shuttle remote manipulator system (SRMS)

This paper presents the development of new mathematical models and algorithms for constrained dynamics of the SRMS and their use in supplementing the On-Orbit Element Simulation (OES) developed by NASA and Lockheed Engineering and Sciences Company (LESC). Emphasis has been placed on maximizing computational efficiency in order to achieve real time implementation and on minimizing modifications to the original open chain OES code. Simulation results for grasping a fixed payload and frictionless planar sliding of a payload are given. Constraint violations are minimized using a simple proportional/derivative control technique. >
Changes in Continence and Erectile Function Between 2 and 4 Years After Radical Prostatectomy

Purpose: There is a paucity of information on changes in continence and erectile function beyond 2 years after radical prostatectomy. We prospectively examined changes in continence and erectile function between 2 and 4 years after radical prostatectomy.Materials and Methods: Between October 2000 and August 2003, 731 consecutive men underwent open retropubic radical prostatectomy for clinically localized prostate cancer. Preoperative and postoperative continence, and erectile function were ascertained using the UCLA Prostate Cancer Index. The 48-month prospective self-assessment followup questionnaire captured changes in urinary control and erectile function between 24 and 48 months, including marked, moderate or slight improvement, no change or worsening.Results: Overall between 24 and 48 months after radical prostatectomy 23.4% and 42.3% of men showed any degree of improvement in continence and erectile function, and 12.2% and 19.8% showed marked and moderate improvement in continence and erectile funct...
Assessing Scientific Measures of Disability

In recent years, there has been an intense drive to promote quantitative measures of disability. Despite evidence demonstrating the existence of social and political dimensions of disability, medical definitions, emphasizing individual functional capacity, have tended to prevail. The present article reviews and critiques existing and emerging disability measures and discusses methodological alternatives based on the life experiences of disabled people as a strategy for improving the scientific measurement of disability.
Double aortic arch in an adult undergoing coronary bypass surgery : a therapeutic dilemma?

Double aortic arch is a congenital anomaly that is rarely found in adults. Typically, this is treated in infancy secondary to symptoms. We describe the treatment of an asymptomatic adult male that was diagnosed with double aortic arch during cardiac catheterization.
Listening for recollection: a multi-voxel pattern analysis of recognition memory retrieval strategies.

Recent studies of recognition memory indicate that subjects can strategically vary how much they rely on recollection of specific details vs. feelings of familiarity when making recognition judgments. One possible explanation of these results is that subjects can establish an internally-directed attentional state ("listening for recollection") that enhances retrieval of studied details; fluctuations in this attentional state over time should be associated with fluctuations in subjects' recognition behavior. In this study, we used multi-voxel pattern analysis of fMRI data to identify brain regions that are involved in listening for recollection. Specifically, we looked for brain regions that met the following criteria: 1) Distinct neural patterns should be present when subjects are instructed to rely on recollection vs. familiarity, and 2) fluctuations in these neural patterns should be related to recognition behavior in the manner predicted by dual-process theories of recognition: Specifically, the presence of the recollection pattern during the pre-stimulus interval (indicating that subjects are "listening for recollection" at that moment) should be associated with a selective decrease in false alarms to related lures. We found that pre-stimulus activity in the right supramarginal gyrus met all of these criteria, suggesting that this region proactively establishes an internally-directed attentional state that fosters recollection. We also found other regions (e.g., left middle temporal gyrus) where the pattern of neural activity was related to subjects’ responding to related lures after stimulus onset (but not before), suggesting that these regions implement processes that are engaged in a reactive fashion to boost recollection.
Behavioural outcome of regulatory problems in infancy

UNLABELLED Infant regulatory problems at 3 mo of age and later hyperkinetic problems in childhood were evaluated in a prospective longitudinal study. CONCLUSION There was a less favourable long-term behavioural outcome in children with multiple regulatory problems. However, family adversity clearly outweighed infant regulatory problems as a predictor of hyperkinetic symptoms.
Design of low-loss and polarization-insensitive reflection grating-based planar demultiplexers

A method for designing polarization-insensitive reflection grating-based planar optical demultiplexer is presented. The grating profile is modified to obtain minimum loss variation over a large (31 nm) bandwidth. Also, the maximum polarization dependent loss variation of only 0.27 dB is obtained over the same spectral range.