cssi/SciSciGPT-SciSciNet huggingface dataset:
NMR Characterization of an Unusual 37 kDa Epimerization Domain of Yersinabactin Synthetase

Nonribosomal Peptide Synthetases (NRPSs) are endogenous microbial supramolecular (1-4 MDa) assemblies that are responsible for the biosynthesis of important natural products, including antibiotics. Genetic reprogramming of NRPS machinery for the generation of novel-or perhaps “designer”-antibiotics (or other therapeutics) represents the apogee of NRPS research. Our model NRPS system is yersiniabactin synthetase (YS), which produces the virulence factor yersiniabactin. Heterocycles (e.g. thiazoline rings) in natural products, such as yersiniabactin, exhibit unique medicinal properties (antibiotic, anticancer, immunosuppressant). An unusual epimerization domain (EA) in YS catalyzes the stereoconversion of a chiral heterocyclic center. Interestingly, EA itself is embedded within the primary sequence of a so-called adenylation domain (A, recognizes and activates substrates). To understand the overall choreography of catalysis, we require structural models of each catalytic domain in its monomeric state, bound to its substrate(s), and in complex with other relevant domains. NRPS domains can be difficult to crystallize in the biologically relevant conformations and complexes, so we take advantage of NMR spectroscopy, which can offer structural, kinetic, thermodynamic, and dynamical data. However, conventional bimolecular NMR experiments will fail on domains such as EA (37 kDa) largely because of relaxation losses but also spectral crowding. This work discusses how nonuniform sampling allowed us to rescue sensitivity and collect preliminary data on a partially deuterated sample. We also exploit covariance NMR spectroscopy to ease the challenging backbone assignment procedure. Using such data we report ∼70% backbone assignment. We also present a chemical biology strategy that will allow us to synthesize otherwise challenging substrates, which will facilitate measurement of steady state kinetic parameters and inform our structural models.
δ-, but not μ- and κ-, opioid receptor activation protects neocortical neurons from glutamate-induced excitotoxic injury

Recent observations from our laboratory have led us to hypothesize that delta-opioid receptors may play a role in neuronal protection against hypoxic/ischemic or glutamate excitotocity. To test our hypothesis in this work, we used two independent methods, i.e., "same field quantification" of morphologic criteria and a biochemical assay of lactate dehydrogenase (LDH) release (an index of cellular injury). We used neuronal cultures from rat neocortex and studied whether (1) glutamate induces neuronal injury as a function of age and (2) activation of opioid receptors (delta, mu and kappa subtypes) protects neurons from glutamate-induced injury. Our results show that glutamate induced neuronal injury and cell death and this was dependent on glutamate concentration, exposure period and days in culture. At 4 days, glutamate (up to 10 mM, 4 h-exposure) did not cause apparent injury. After 8-10 days in culture, neurons exposed to a much lower dose of glutamate (100 microM, 4 h) showed substantial neuronal injury as assessed by morphologic criteria (>65%, n=23, P<0.01) and LDH release (n=16, P<0. 001). Activation of delta-opioid receptors with 10 microM DADLE reduced glutamate-induced injury by almost half as assessed by the same criteria (morphologic criteria, n=21, P<0.01; LDH release, n=16, P<0.01). Naltrindole (10 microM), a delta-opioid receptor antagonist, completely blocked the DADLE protective effect. Administration of mu- and kappa-opioid receptor agonists (DAMGO and U50488H respectively, 5-10 microM) did not induce appreciable neuroprotection. Also, mu- or kappa-opioid receptor antagonists had no appreciable effect on the glutamate-induced injury. This study demonstrates that activation of neuronal delta-opioid receptors, but not mu- and kappa-opioid receptors, protect neocortical neurons from glutamate excitotoxicity.
Tacitus' fragment 2 : The anti-Roman movement of the Christiani and the nazoreans

There is little consensus as to the historical nature of the sect identified by Tacitus in Annales 15.44 as the Christiani. Nor is there any firm consensus on the authenticity and historicity of all of that fragment known as Tacitus' fragment 2 (= Sulpicius Severus (Chronica 2.30.6-7), whose references to "Christiani" are widely suspected of being later Christian interpolations. Much of this fragment is thought, nevertheless, to be from the lost portion of the fifth book of Tacitus' Historiae. A solution can be found to both of these problems by adducing from fragment 2 new evidence indicating that this fragment indeed represents a primary historical source. This new evidence takes the form of the discovery of a significant statistical relationship among the following three words: (1) The metaphor stirps (branch, descendants) used to describe the Christiani in fragment 2, (2) and (3) Nαζωραioζ and Nαζαρηνoζ (Nazorean), describing the New Testament sect associated with the of Acts 11.26. The connecting link among, as well as the common source for, the three words listed above appears to be the Hebrew netser (branch, descendants-apparently influenced by Isa 11.1), which both translates into stirps and translitcrates into N It is mathematically extremely unlikely that this link with netser represents a random coincidence. Also, it appears that a later Christian redactor of fragment 2 or his target audience would not have known of this connection. Because of this and other contextual explanations, the possibility is largely eliminated that fragment 2 could have been significantly redacted by a later Christian. We are thus left with the substantial probability that this fragment constitutes a primary historical source, most likely via Tacitus. In turn this source supplies us with a probable solution to the problem of the Christiani's identity by depicting them in fragment 2 as being major participants in the first Jewish revolt against Rome in 66-73 CE.
Algorithm architectures to support large-scale process systems engineering applications involving combinatorics, uncertainty, and risk management

Increased information intensity is greatly expanding the importance of model-based decision-making in a variety of areas. This paper reviews applications that involve large-scale combinatorics, data uncertainty, and game theoretic considerations and describes three related algorithm architectures that address these features. In particular, highly customized mathematical programming architectures are discussed for time-based problems involving significant combinatorial character. These architectures are then embedded into a simulation-based optimization (SIMOPT) architecture to address both combinatorial character and significant data uncertainty. Multiple SIMOPT objects are combined using a coordinating architecture to address game theoretic issues. A key focus of the paper is a discussion of the algorithm engineering principles necessary to mitigate the NP-complete nature of practical problems. The life cycle issues of algorithm delivery, control, support, and extensibility are important to sustained use of advanced decision-making technology. An inductive development methodology provides a means for developing sophisticated algorithms that become increasingly powerful as they are subjected to new constraint combinations. Implicit generation of formulations is crucial to routine large-scale use of mathematical programming based architectures.
Complications of acute pancreatitis: helical CT evaluation

Acute pancreatitis represents one of the more commonly encountered etiologies of acute abdominal pain. Many complications can present emergently, including pancreatic abscess, necrosis, and hemorrhage. The purpose of this pictorial essay is to educate the reader about the spectrum of CT findings in patients with complications from pancreatitis. Emphasis is placed on evaluation with helical CT, stressing optimal technique and the imaging parameters essential for accurate diagnosis.
Inverse sign of the chiral-optical effects of non-planar heteroannular cisoid dienes

Abstract The chiral-optical effects of heteroannular cisoid dienes are attributed to the dissymmetry of the skewed diene chromophore as in the case of homoannular cisoid dienes and of transoid dienes. The sign of these effects for a small number of heteroannular cisoid dienes is opposite to that predicted from the “diene rule” (1). This inversion of sign is ascribed to the change in electronic properties of the diene when, as in these compounds, the dihedral angle about the central bond is very large compared to that of the homoannular dienes. Consistent with these observations, recent theoretical treatments of the functional dependence of the rotatory strengths on the dihedral angle demonstrate that the sign of the CD and ORD effects can change at large angles.
Race, Place, and the Bounds of Humanity1

The idea of a human-animal divide as reflective of both differences in kind and in evolutionary progress, has retained its power to produce and maintain racial and other forms of cultural difference. During the colonial period, representations of similarity were used to link subaltern groups to animals and thereby racialize and dehumanize them. In the postcolonial present, however, animal practices of subdominant groups are typically used for this purpose. Using data on cultural conflicts surrounding animal practices collected from media sources, we show that such practices have become a key aspect of the human-animal boundary due to the radically changing time-space relations of postmodernity. Drawing on Spivak's notion of "wild practice, " we propose a radical democracy that includes animals as well as subaltern peoples, and argue for the rejection of dehumanization as a basis for cultural critique, given its role in perpetuating racialization and violence toward both human and non-human animals.
On Some Aradidae from the Old and New World (Hemiptera‐Heteroptera)

Kormilev, N. A. (84–05 89th Street, Woodhaven, N.Y. 11421, USA). On some Aradidae from the Old and New World (Hemiptera-Heteroptera). Zool. Scr. 5 (2): 67–78, 1976. — The author proposes and describes the following new taxa: Aradus malaisei sp.n. and A. burmensis sp.n. (both from Burma); Calisiopsis planiceps sp.n. (Brasil, S. Catarina); Aneurus burmensis sp.n. (Burma); A. brevirostris sp.n. (Malaya, Perak); A. ampliatus sp.n. (East Africa); Kiritshenkiana furconotata gen.n., sp.n. (Malaya, Perak) Apteraradus similis sp.n. (Malaya, Perak); Camerarius armigerus sp.n. (Malaya, Perak); Artabanus bellicosus sp.n. (Malaya, Perak); Arictus grandis sp.n. (Malaya, Perak); Neuroctenus burmensis sp.n. (Burma); N. perssoni sp.n. (Burma); Notapictinus plaumanni sp.n. (Brasil, S. Catarina); Mezira brasiliensis sp.n. (Brasil, S. Catarina); Mezira (Zemira) incognita sp.n. (Patria ignota); Chrysodaspis armatus sp.n. (Malaya, Perak); C. aurivillii sp.n. (Patria ignota). For two of the species the locality is unknown (patria ignota) but they were collected during a journey to Java and adjacent islands. Key to the species of Calisiopsis Champion, 1898, is given.
Continuing engineering education by electronic blackboard and videotape: a comparison of on-campus and off-campus student performance

The authors discuss student performance in the two different systems that the University of Illinois at Urbana-Champaign employs for its remote delivery of off-campus courses in continuing engineering education. The two systems are the AT&T Gemini 100 Electronic Blackboard system and videotaping courses in a studio classroom setting. Three sets of findings are reported about comparisons of on and off-campus student performance in the same engineering courses offered from 1979 through 1986, and these findings are then related to pertinent literature. The first compares on and off-campus students in electronic blackboard courses over the seven-year period, the second compares on and off-campus students in videotape courses, and the third set of findings compares and contrasts results on student performance resulting from the two types of off-campus delivery systems. >
Nonuniversal gaugino masses and seminatural supersymmetry in view of the Higgs boson discovery

I consider models with non-universal gaugino masses at the gauge coupling unification scale, taking into account the Higgs boson discovery. Viable regions of parameter space are mapped and studied in the case of non-universality following from an F-term in a linear combination of singlet and adjoint representations of SU(5). I consider, in particular, "semi-natural" models that have small \mu, with gaugino masses dominating the supersymmetry breaking terms at high energies. Higgsino-like particles are then much lighter than all other superpartners, and the prospects for discovery at the Large Hadron Collider can be extremely challenging.
Cokriging—a computer program

Abstract Cokriging is a process wherein several variables can be jointly estimated on the basis of intervariable and spatial structure information. Presented herein is the program COKRIG, for punctual cokriging, a program in a simple form to demonstrate the utility of cokriging. Equation solution follows a modification of a method developed for the solution of large-scale linear systems. Several example problems show that, at least for earthquake data, the inclusion of intervariable information results in a more accurate BLUE (best linear unbiased estimator).
Forecasting volatility using range data: analysis for emerging equity markets in Latin America

The article suggests a simple but effective approach for estimating value-at-risk thresholds using range data, working with the filtered historical simulation. For this purpose, we consider asymmetric heterogeneous Autoregressive Moving Average (ARMA) model for log-range, which captures the leverage effects and the effects from daily, weekly and monthly horizons. The empirical analysis on stock market indices on the US, Mexico, Brazil and Argentina shows that 1% and 5% Value at Risk (VaR) thresholds based on one-step-ahead forecasts of log-range are satisfactory for the period includes the global financial crisis.
Polyethylene glycol distearate 600 with 10 per cent 1-hexadecanol; a superior embedding wax for warm climates.

A mixture of 90% polyethylene glycol distearate 600 and 10% 1-hexadecanol has a melting point of approximately 43 C and is suitable as a replacement for conventional polyester wax where laboratory temperatures are above 24 C. Sections are attached to slides by floating out on 10% formalin and picked up on slides precoated with undiluted egg albumen. Since the wax is opaque, very small specimens can be embedded after fixation in a block of 0.5% agar before dehydration and embedding in wax, thus facilitating their handling and orientation. The wax mixture sections well with a razor blade in a holder.
247Cm as a Short-lived r-Process Chronometer

Nucleocosmochronological studies1–3 have used two short-lived isotopes (relative to the age of the Solar System), 129I(τ1/2 = 1.7 × 107 yr) and 244Pu(τ1/2 = 8.2 × 107 yr). Short-lived isotopes provide valuable information about the early history of the Solar System and, in particular, about meteorite parent bodies. Additional short-lived chronometers, particularly if created by different nucleosynthetic processes, would be very useful. The two isotopes 129I and 244Pu are believed to be produced (essentially) entirely by the r-process.
Dynamo Action of Fluid Motions with Two-Dimensional Periodicity

In a previous paper it has been established that almost all spatially periodic motions of an infinite homogenous conducting fluid give magnetohydrodynamic dynamo action for almost all values of the magnetic diffusivity or resistivity A. It was shown that there is a dynamo action if and only it or some real vector j there is a growing magnetic field solution of the form where the complex vector function H(x) has the same periodicity as the motion. The complex growth rate b was studied in a first-order limit of small j to obtain the above result. In this sequel the special case of spatially periodic motions with their three components functions of the two Cartesian coordinates y and z only is considered. The first-order method establishes dynamo action for only half, in a certain sense, of the motion-resistivity combinations. It is shown that the two-dimensional spatially periodic motion u = (cos y — cos z, sin z, sin y) is a first-order dynamo, at least for almost all resistivities. Three similar motions, which are not firstorder dynamos for any resistivity, are also studied. It is proved that multiple-scale versions of all three can give growing magnetic fields for certain resistivities when terms of higher order in j are included. Heuristic descriptions of all four dynamo mechanisms are given. A numerical method is described for determining the most rapidly growing magnetic field solution ot toe above form, and results for all four motions are presented, giving the growth rate R e/, as a function of j for a range of resistivities A down to about 10~a. The first motion gives growing solutions for all resistivities in this range, the others give dynamo action only for resistivities below critical values near unity. The numerical and analytic results agree.
Recovery of DNA fragments inserted by the "tailing" method: regeneration of PstI restriction sites.

A general method has been developed for the recovery of any DNA fragment inserted into a cloning vehicle containing a single endonuclease PstI site. Endonuclease PstI sites are regenerated by the addition of one or more deoxyguanosine residues to the 3' termini of the PstI-cleaved vehicle by terminal deoxynucleotidyl transferase. Chain elongation by terminal deoxynucleotidyl transferase is then continued with dITP, dATP or dGTP. A plasmid vehicle, pAO1, containing a single PstI site has been constructed. Insertional (foreign) DNA fragments that were “tailed” with dCTP have been annealed to PstI-deaved pAO1 that was “tailed” with dGTP. When the annealed fragments were used to transform competent Escherichia coli cells, the single-stranded DNA gaps in the recombinant plasmids were repaired. Plasmids recovered from transformed bacteria could be cleaved by PstI into the insertional DNA with dG:dC tracts and linear pAO1 molecules.
Handling of Single Brain Metastasis

As recently as a few decades ago, the diagnosis of metastasis was a sure death sentence. The malignant tumor had clearly spread to distant regions and mortality was imminent and una
Tactile Recognition and Localization Using Object Models: The Case of Polyhedra on a Plane

This paper discusses how data from multiple tactile sensors may be used to identify and locate one object, from among a set of known objects. We use only local information from sensors: 1) the position of contact points and 2) ranges of surface normals at the contact points. The recognition and localization process is structured as the development and pruning of a tree of consistent hypotheses about pairings between contact points and object surfaces. In this paper, we deal with polyhedral objects constrained to lie on a known plane, i.e., having three degrees of positioning freedom relative to the sensors. We illustrate the performance of the algorithm by simulation.
Height, weight, and mortality in a population of longshoremen.

Abstract The 3,992 examined longshoremen, averaging 17 per cent over Metropolitan standard of weight for height, show no excess of mortality from all causes and no excess from coronary heart disease during the first 5 years after examination. They show no gradient of total mortality with weight, even those 40 per cent and more over Metropolitan standard of weight for height showing no excess mortality. The 78 examined longshoremen who died of coronary heart disease in the 5 years after examination did not differ in weight from the total of those examined. Only 12 of the 78 coronary heart deaths occurred among those diagnosed as having coronary heart disease after referral for positive findings at the multiphasic screening examination.
Integrating Service Learning into the College Chemistry Curriculum

General chemistry students often complain that they are unmotivated because they see no applications of chemical principles in ‘real life.’ Instructors become frustrated by these complaints because they see the world as nothing less than a cornucopia of applications of chemistry. How can students learn that chemistry does apply to real life? In this paper, we describe service learning, a powerful strategy for integrating chemistry, community service, and real-life applications in the general chemistry curriculum.
Dynamic disparity adjustment and histogram-based filtering of range data for fast 3-D hand tracking

Range data is very important in human-computer interaction applications. Although less costly, range acquisition and processing still presents a speed vs data reliability tradeoff. This paper proposes a method that, given noisy and generally unreliable range data, can filter out erroneous information using range histograms for regions of interest selected in registered color data. Then, using the resulting consistent data that has passed filters, this method limits the depth search space dynamically using motion history and its current state. Experimental results demonstrate the success of the proposed algorithm. Using filtered range data, the algorithm correctly identified the hand involved in manipulation 99.85% of the time. Dynamic disparity adjustment produced a speedup of 60.17% over a static disparity range selection. An application to virtual reality navigation is also presented.
Surface immunoglobulin-mediated B-cell activation in the absence of detectable elevations in intracellular ionized calcium: a model for T-cell-independent B-cell activation

Abstract We recently showed that anti-immunoglobulin conjugated to high molecular weight dextran is 1000-fold more mitogenic for B cells than unconjugated anti-immunoglobulin. This system serves as a model for T-cell-independent type 2 antigens such as haptenated Ficoll, dextran, and bacterial polysaccharides, which can also stimulate B-cell proliferation and antibody production at low concentrations. We show here that conjugated anti-immunoglobulin, at concentrations that stimulate significant increases in expression of major histocompatibility complex class II molecules and incorporation of thymidine into DNA, does not induce detectable modulation of surface immunoglobulin. These results indicate that the facilitated T-cell-independent B-cell activation by polysaccharide antigens may result from inability to modulate surface immunoglobulin, possibly resulting in persistent and/or repetitive signaling. Early large increases in Ca2+ and breakdown of inositol phospholipids presently thought to be involved in transduction of the mitogenic signal are not detectable at low concentrations of conjugated anti-immunoglobulin, raising the possibility that these biochemical events may not in fact be central to this signaling pathway.
Air pollutant retention within a complex of urban street canyons

a b s t r a c t Epidemiological studies of health effects associated with ambient air pollution are subject to uncertainty in the effects estimates related to the spatial and temporal variability of ambient air pollution. This study examines meteorological and concentration decay data for an urban canopy in Oklahoma City, OK to develop a modeling approach that can be used to estimate spatiotemporal variability in contaminant retention that could add bias or uncertainty to epidemiological results. Concentration and microscale turbulent wind data from the Joint Urban 2003 study were reanalyzed to examine scaling relationships between contaminant residence time in urban street canyons, urban boundary layer winds, and urban topography. Street-level sulfur hexa fluoride (SF6) concentration time series were reviewed to find time periods that included a peak and decay. Exponential decay curves were fitted to each period, and a characteristic residence time was derived from each model slope. That residence time was nondimensionalized by the ratio of mean urban boundary layer wind speed to height of the building just upwind of the street canyon in which the concentration was measured. Sonic detection and ranging (SODAR) data were used to assess atmospheric turbulence conditions at times concurrent with the concentration decay measurements. Reynolds number ( Re ) was calculated from the 15-min average wind velocity and ranged from 2.1 ! 10 6 to 7.6 ! 10 7 . Nondimensional residence time ( H) ranged from 3.7 to 996 with a median of 13.3. Inverse relationships were validated between H and Re and between H and the street canyon aspect ratio. These relationships provided a mechanism to understand time-varying ventilation within a street canyon. The results shown here were intended to demonstrate how scaling relationships derived from the transport equation can be used to provide rapid estimates of characteristic decay times for the purpose of estimating variability in the concentrations encountered in an urban environment. This could be a useful tool to reduce uncertainty in air pollution epidemiological study results related to spatial and temporal variability in urban concentrations. Published by Elsevier Ltd.
Measurement of kon without a rapid‐mixing device

We have recently designed a biochemistry laboratory experiment for the purpose of providing students an advanced experience with enzyme kinetics and the kinetics of binding. Bestatin, a well-known and commercially available general protease inhibitor, is a slow-binding inhibitor of aminopeptidase isolated from Aeromonas proteolytica. The binding is on a timescale slow enough for measurement without the use of a rapid-mixing device. Aminopeptidase inhibition is detected via a standard colorimetric assay with an inexpensive commercially available substrate. The binding of bestatin follows first order binding kinetics with a rate constant kon of 59 ± 5 M−1 s−1. This aminopeptidase is well characterized with several crystal structures and a published Ki, which students can then use to calculate the value for koff.
Annealing Effect of Cermet Membranes on Hydrogen Permeability

Ni–SrCe0.8Yb0.2O3−δ cermet membranes are being developed to separate hydrogen from hydrogen-containing gas mixtures at high temperature. The hydrogen flux of an annealed membrane showed higher flux...
A Clinicopathologic Study of Optic Neuropathies Associated by Intracranial Mass Lesions by Quantification of Remaining Axons

We examined three patients with intracranial mass lesions that damaged the anterior visual pathway and studied this damage histologically after the patients died. Estimation of the number of surviving axons in the six optic nerves generally showed the greatest atrophy to be in the temporal sector in cross sections immediately behind the globe. More posterior to the globe, atrophy appeared greatest in the center of several nerves. This pattern of damage may result from particular vulnerability of macular axons to damage along the anterior visual pathway. Optic disk pallor was present in two eyes that had less than 40% of the normal number of axons remaining, while one optic disk appeared to be normal with 70% of the axons intact. Afferent pupillary defects were observed in two patients who had two to three times as many remaining axons in the contralateral optic nerve as in the nerve on the side of the defect.
Effects of host temperature and gastric and duodenal environments on microsporidia spore germination and infectivity of intestinal epithelial cells

Approximately 14 of the more than 1,000 species of microsporidia infect humans, only two of which, Enterocytozoon bieneusi and Encephalitozoon intestinalis, cause intestinal microsporidiosis. Clinical isolates of three microsporidia species, E. intestinalis, Encephalitozoon hellem, and the insect parasite, Anncaliia (Brachiola, Nosema) algerae were used in a spore germination assay, and enterocyte attachment and infection assays were performed to model the potential roles of gastric and duodenal environments and host temperature in determining why only one of these microsporidia species causes intestinal microsporidiosis. Enterocyte infection with A. algerae spores was 10% that of the Encephalitozoon species, a difference not attributable to differences in spore attachment to host cells. Prior spore treatment with pepsin in HCl, pancreatic enzymes, or ox bile did not inhibit germination or enterocyte infection by the three microsporidia species. While the Encephalitozoon species differentiated to mature spores within 3 days, the time taken for many enterocytes to turn over, A. algerae took 3-5 days to produce mature spores, near the upper limit for enterocyte turnover in vivo. Thus, host temperature may contribute to A. algerae not causing human intestinal microsporidiosis, but none of the factors tested account for the inability of E. hellem to cause such an infection.
Wake properties of a single gas bubble in three-dimensional liquid-solid fluidized bed

Abstract Experiments were performed to investigate the wake properties of a single gas bubble in a three-dimensional liquid-solid fluidized bed via a video camera moving at the same speed as the bubble. The solids holdup in the fluidized bed varied up to around 10%. The bubble size varied from 5 to 20 mm with corresponding bubble Reynolds numbers ranging from 1000 to 6500. The bubble was observed to have two types of wake configurations depending on the bubble size: the asymmetric/helical vortex wake for small bubbles and the symmetric wake for large bubbles. The bubble shape and relative rise velocity in the fluidized bed can be well-represented by correlations developed for single bubbles in liquid media, although the bubble shape in liquid-solid media is slightly more flattened compared to that in liquid media. The bubble rocking frequency was found to be independent of particle properties and to correspond in magnitude to the vortex shedding frequency in a two-dimensional liquid-solid fluidized bed. The average primary wake size in three dimensions is comparable to that in two dimensions.
Time-frequency structure of the high-resolution ECG

This study considers the problem of representing high-resolution ECG (HRECG) signals in the time-frequency plane using spectrotemporal mapping (STM). High-resolution ECG signal components overlap in both time and frequency. The central issue with STM techniques is whether sufficient time-frequency resolution exists to discriminate normal and abnormal QRS signals. The trade-off between signal resolution in time and in frequency must be made without a priori knowledge of the HRECG's time-frequency structure. A simulation experiment was performed to examine the time-frequency distribution of normal, abnormal low-level (late potentials), and bundle branch block components of the QRS. Results suggest that discrimination of these signals with STM is problematic. Signals and noise within the HRECG ensemble can, however, be easily distinguished. This observation forms the basis of a new optimally filtered ensemble averaging technique for signal-to-noise ratio enhancement.
The effect of landscape structure on community self-organization and critical biodiversity

Critical biodiversity has been defined as the level of species richness at which communities are most susceptible to disturbance, where even small perturbations resulting from the introduction or extinction of a single species may trigger a mass extinction event. Beyond this threshold, it has been hypothesized that ordered communities with well-defined spatial structure will spontaneously form; these ordered communities are predicted to be resilient to small perturbations such that mass extinctions will no longer occur. We adopted a complex systems approach to explore how landscape pattern affected the critical biodiversity threshold (Sc) and the ability of communities to self-organize in heterogeneous random and fractal landscapes representing a gradient of spatial contagion. Communities that evolved in random and clumped fractal (H = 1.0) landscapes attained nearly the same average species richness (random S = 22, fractal S = 20.5), but the range of variation in community species richness was 3× greater in random landscapes (random CV = 66%, fractal CV = 21%). Some communities that formed on random landscapes collapsed completely and never recovered, whereas complete system collapse never occurred on landscapes with a high degree of spatial contagion (clumped fractal). Nevertheless, spatial contagion initially enhanced the susceptibility of communities to mass extinction, and thus the critical biodiversity threshold was higher in landscapes with high spatial contagion (random Sc = 15; clumped fractal Sc = 20). In other words, a greater number of species was ultimately required to buffer communities from the small perturbations that occasionally triggered mass extinctions on these highly ordered landscapes. The likelihood of attaining this critical biodiversity was also affected by landscape structure. Communities on clumped fractal landscapes evolved to (or got stuck at) the critical biodiversity threshold, whereas communities with an intermediate degree of order ( H = 0.5) generally evolved beyond this point and attained a high level of species richness. Spatial structure is not a prerequisite for the emergence of community structure, but organized communities are inevitable in highly structured (ordered) landscapes. Order begets order and this order ultimately enhances system stability and the susceptibility of the system to mass extinction. © 2004 Elsevier B.V. All rights reserved.
Foodborne Salmonella ecology in the avian gastrointestinal tract

Foodborne Salmonella continues to be a major cause of salmonellosis with Salmonella Enteritidis and S. Typhimurium considered to be responsible for most of the infections. Investigation of outbreaks and sporadic cases has indicated that food vehicles such as poultry and poultry by-products including raw and uncooked eggs are among the most common sources of Salmonella infections. The dissemination and infection of the avian intestinal tract remain somewhat unclear. In vitro incubation of Salmonella with mammalian tissue culture cells has shown that invasion into epithelial cells is complex and involves several genetic loci and host factors. Several genes are required for the intestinal phase of Salmonella invasion and are located on Salmonella pathogenicity island 1 (SPI 1). Salmonella pathogenesis in the gastrointestinal (GI) tract and the effects of environmental stimuli on gene expression influence bacterial colonization and invasion. Furthermore, significant parameters of Salmonella including growth physiology, nutrient availability, pH, and energy status are considered contributing factors in the GI tract ecology. Approaches for limiting Salmonella colonization have been primarily based on the microbial ecology of the intestinal tract. In vitro studies have shown that the toxic effects of short chain fatty acids (SCFA) to some Enterobacteriaceae, including Salmonella, have resulted in a reduction in population. In addition, it has been established that native intestinal microorganisms such as Lactobacilli provide protective mechanisms against Salmonella in the ceca. A clear understanding of the key factors involved in Salmonella colonization in the avian GI tract has the potential to lead to better approach for more effective control of this foodborne pathogen.
Chronic Obstructive Pancreatitis as a Delayed Complication of Pancreatic Trauma

Increasing surgical experience with the immediate consequences of pancreatic injuries has resulted from parallel growth in the volume of motor vehicle accidents and societal violence. However, few surgeons are aware that complications may be considerably delayed following pancreatic trauma, occurring in some cases months to years after apparent recovery from the original injury. In four patients with blunt pancreatic trauma initially treated by non-operative means, stricture of the main pancreatic duct developed over a period of months as a result of progressive fibrosis at the site of ductal injury. Pancreatic duct hypertension was demonstrated to be present in the obstructed duct, and secondary changes of chronic pancreatitis developed in the obstructed segment of the gland (“upstream” chronic pancreatitis). Seven similar patients with delayed onset of chronic obstructive pancreatitis after pancreatic trauma were found in the literature. Symptoms related to these acquired ductal strictures are most commonly those of abdominal pain and recurrent episodes of acute pancreatitis. Recognition of post-traumatic chronic obstructive pancreatitis principally involves awareness that injuries to the pancreatic duct can produce remote complications. Pancreatoenteric drainage, or resection of the obstructed segment of pancreas, provides prompt and effective relief.
Energies, geometries, and charge distributions of ZN molecules, clusters, and biocenters from coupled cluster, density functional, and neglect of diatomic differential overlap models

We present benchmark databases of Zn-ligand bond distances, bond angles, dipole moments, and bond dissociation energies for Zn-containing small molecules and Zn coordination compounds with H, CH3, C2H5, NH3, O, OH, H2O, F, Cl, S, and SCH3 ligands. The test set also includes clusters with Zn-Zn bonds. In addition, we calculated dipole moments and binding energies for Zn centers in coordination environments taken from zinc metalloenzyme X-ray structures, representing both structural and catalytic zinc centers. The benchmark values are based on relativistic-core coupled cluster calculations. These benchmark calculations are used to test the predictions of four density functionals, namely B3LYP and the more recently developed M05-2X, M06, and M06-2X levels of theory, and six semiempirical methods, including neglect of diatomic differential overlap (NDDO) calculations incorporating the new PM3 parameter set for Zn called ZnB, developed by Brothers and co-workers, and the recent PM6 parametrization of Stewart. We found that the best DFT method to reproduce dipole moments and dissociation energies of our Zn compound database is M05-2X, which is consistent with a previous study employing a much smaller and less diverse database and a much larger set of density functionals. Here we show that M05-2X geometries and single-point coupled cluster calculations with M05-2X geometries can also be used as benchmarks for larger compounds, where coupled cluster optimization is impractical, and in particular we use this strategy to extend the geometry, binding energy, and dipole moment databases to additional molecules, and we extend the tests involving crystal-site coordination compounds to two additional proteins. We find that the most predictive NDDO methods for our training set are PM3 and MNDO/d. Notably, we also find large errors in B3LYP for the coordination compounds based on experimental X-ray geometries.
Regulation of liver regeneration by suppressors of cytokine signaling-3

control Rotenone (10uM) FCCP control FCCP (10uM) Thapsigargin control Thapsigargin (1uM) Oligomycin control Oligomycin (5ug/mL) RU360 control RU360 (10uM) Ratio of rates (RR)a 0.83 0.11 1.29 0.29 0.80 0.06 3.18 1.17 1.00 0 1.08 0.10 1.00 0 2.1 0.47 0.80 0.14 0.67 0.14 Fluorescenceb 0.23 0.084 0.48 0.16 0.29 0.05 0.74 0.13 0.16 0.05 0.09 0.04 0.18 0.08 0.41 0.12 0.23 0.07 0.26 0.08 Number of cells 67 41 92 84 28 40 24 55 31 49
Sutureless anchors in shoulder surgery

Since the introduction of sutureless anchors for shoulder surgery in the late 1980s, multiple reports of their success in shoulder surgery have been published. Current use of sutureless anchors in shoulder surgery include stabilization and rotator cuff surgeries. Techniques for rotator cuff repair and Bankart stabilization are described in this article. The overriding reason for their continued use is the simplicity of their insertion, making them a very attractive alternative for arthroscopic shoulder surgery. Usually a guide wire is inserted through the rotator cuff or the capsulolabral tissue and driven into the bone. The cannulated drill or tap is then inserted over the guide wire to the desired level and exchanged for the placement of the sutureless anchor. A review of the latest literature reveals that these procedures’ overall success is inferior to that of suture anchors. Furthermore, sutureless anchors have also been associated with possibly significant complications such as inflammatory reactions, intraarticular migration, and failure of reduction, although the relative incidence compared with suture anchors is unclear. However, there may still be a place for sutureless anchors in clinical practice.
Promoting Wellness in Alaskan Villages: Integrating Traditional Knowledge and Science of Wild Berries

People draw upon multiple forms of environmental knowledge, from scientific to highly contextual local or traditional forms of knowledge, to interpret problems and gauge risks in complex socio-ecological systems. In collaboration with three remote Alaska Native communities, and using an interdisciplinary, participatory, and mixed methods research approach, we explored traditional ecological knowledge and scientific aspects of wild berries and the broader context of community health and environmental change. Combining site visits, key informant interviews, focus groups, survey questionnaires, portable field bioassays, and laboratory follow-up analyses, our research revealed the importance of local subsistence resources for community wellness. Multiple berry species were found to have powerful bioactive health properties for ameliorating metabolic syndrome as well as importance for community wellness. Communities differed in the degree to which they characterized berries as healthy foods and perceived environmental risks including climate change. Findings suggest the importance of incorporating locally available foods and socio-cultural traditions into community wellness programming. This article also discusses challenges and opportunities associated with transdisciplinary, participatory research with indigenous communities.
Techniques for large zone segmentation of seismic images

Seismic techniques play an important role in the exploration for hydrocarbon deposits. The authors describe three knowledge-based segmentation techniques and compare their performance on a real seismic image. The first technique is based on a run length statistics algorithm extended by a decision process which incorporates heuristic rules to influence the segmentation. The second and third techniques are based on texture energy measures algorithms augmented by two knowledge-based classification processes. The knowledge-based process of the second technique is controlled by a parallel region growing scheme and that of the third technique is controlled by an iterative quadtree spitting scheme. Their results show that the third technique, which is based on texture measures augmented with a knowledge-based quadtree splitting scheme, provides a better segmentation of the test image than the other two.
Depressed perivascular sensory innervation of mouse mesenteric arteries with advanced age

Key points The dilatory role for sensory innervation of mesenteric arteries (MAs) is impaired in Old (∼24 months) versus Young (∼4 months) mice. We investigated the nature of this impairment in isolated pressurized MAs. With perivascular sensory nerve stimulation, dilatation and inhibition of sympathetic vasoconstriction observed in Young MAs were lost in Old MAs along with impaired dilatation to calcitonin gene-related peptide (CGRP). Inhibiting NO and prostaglandin synthesis increased CGRP EC50 in Young and Old MAs. Endothelial denudation attenuated dilatation to CGRP in Old MAs yet enhanced dilatation to CGRP in Young MAs while abolishing all dilatations to ACh. In Old MAs, sensory nerve density was reduced and RAMP1 (CGRP receptor component) associated with nuclear regions of endothelial cells in a manner not seen in Young MAs or in smooth muscle cells of either age. With advanced age, loss of dilatory signalling mediated through perivascular sensory nerves may compromise perfusion of visceral organs. Abstract Vascular dysfunction and sympathetic nerve activity increase with advancing age. In the gut, blood flow is governed by perivascular sensory and sympathetic nerves but little is known of how their functional role is affected by advanced age. We tested the hypothesis that functional sensory innervation of mesenteric arteries (MAs) is impaired for Old (24 months) versus Young (4 months) C57BL/6 male mice. In cannulated pressurized MAs preconstricted 50% with noradrenaline and treated with guanethidine (to inhibit sympathetic neurotransmission), perivascular nerve stimulation (PNS) evoked dilatation in Young but not Old MAs while dilatations to ACh were not different between age groups. In Young MAs, capsaicin (to inhibit sensory neurotransmission) blocked dilatation and increased constriction during PNS. With no difference in efficacy, the EC50 of CGRP as a vasodilator was ∼6-fold greater in Old versus Young MAs. Inhibiting nitric oxide (l-NAME) and prostaglandin (indomethacin) synthesis increased CGRP EC50 in both age groups. Endothelial denudation reduced the efficacy of dilatation to CGRP by ∼30% in Old MAs yet increased this efficacy ∼15% in Young MAs while all dilatations to ACh were abolished. Immunolabelling revealed reduced density of sensory (CGRP) but not sympathetic (tyrosine hydroxylase) innervation for Old versus Young MAs. Whereas the distribution of CGRP receptor proteins was similar in SMCs, RAMP1 associated with nuclear regions of endothelial cells of Old but not Young MAs. With advanced age, the loss of sensory nerve function and diminished effectiveness of CGRP as a vasodilator is multifaceted and may adversely affect splanchnic perfusion.
Effects of symptoms of co-morbid psychopathology on challenging behaviours among infants and toddlers with Autistic Disorder and PDD-NOS as assessed with the Baby and Infant Screen for Children with aUtIsm Traits (BISCUIT).

Purpose: To examine whether level of symptoms of co-morbid psychopathology exacerbated challenging behaviours in young children with autism spectrum disorders (ASD).Method: Using the Baby and Infant Screen for Children with aUtIsm Traits (BISCUIT)–Part 2 which measures co-morbid symptoms and the BISCUIT- Part 3 which examines challenging behaviours, 362 infants and toddlers with ASD were evaluated.Results: Findings showed that participants scoring high on symptoms of Avoidance and Tantrum/Conduct problems had greater rates of aggressive/destructive behaviours, self-injurious behaviours (SIB) and stereotypies compared to those with low scores. Participants with high levels of Inattention/Impulsivity or Eat/Sleep concerns, compared to those with low levels, demonstrated greater aggressive/destructive behaviour and stereotypies. For symptoms of Anxiety/Repetitive Behaviours, participants with high scores displayed greater levels of stereotypies.Conclusions: Symptoms of co-morbid psychopathology are present a...
Common-Space Ideal Points, Committee Assignments, and Financial Interests in the State Legislatures

We present a new unified dataset of common-space ideal points, committee assignments, and financial interests for all state legislators in 1999. We describe the compilation of the dataset and offer a few possible applications.