cssi/SciSciGPT-SciSciNet huggingface dataset:
Diabetic cranial mononeuropathies: a patient's perspective.

Diabetic neuropathy is a common complication of diabetes mellitus. The cranial mononeuropathies are most prevalent among the elderly. The incidence, classifi cation, pathophysiology, assessment, and treatment of diabetic cranial mononeuropa thies are presented. The author also includes a personal experience to help diabetes educators understand the effects of these disorders so they will be better able to explain them to affected patients.
Fabrication and testing of the first 8.4-m off-axis segment for the Giant Magellan Telescope

The primary mirror of the Giant Magellan Telescope consists of seven 8.4 m segments which are borosilicate honeycomb sandwich mirrors. Fabrication and testing of the off-axis segments is challenging and has led to a number of innovations in manufacturing technology. The polishing system includes an actively stressed lap that follows the shape of the aspheric surface, used for large-scale figuring and smoothing, and a passive "rigid conformal lap" for small-scale figuring and smoothing. Four independent measurement systems support all stages of fabrication and provide redundant measurements of all critical parameters including mirror figure, radius of curvature, off-axis distance and clocking. The first measurement uses a laser tracker to scan the surface, with external references to compensate for rigid body displacements and refractive index variations. The main optical test is a full-aperture interferometric measurement, but it requires an asymmetric null corrector with three elements, including a 3.75 m mirror and a computer-generated hologram, to compensate for the surface's 14 mm departure from the best-fit sphere. Two additional optical tests measure large-scale and small-scale structure, with some overlap. Together these measurements provide high confidence that the segments meet all requirements.
Drought research and monitoring program is focus of congressional hearing

With more than 70% of the United States currently classified as being anywhere from abnormally dry to experiencing exceptional drought—according to the U.S. Drought Monitor, a consensus product of U.S. federal and academic scientists—witnesses at a 25 July U.S. House of Representatives committee hearing expressed concern about the impact of the drought and voiced strong support for reauthorizing the National Integrated Drought Information System (NIDIS). Republican and Democratic members of the House Science, Space, and Technology Committee also expressed their support for NIDIS, which is part of the National Oceanic and Atmospheric Administration's (NOAA) Climate Program Office and is currently authorized through 2012. However, members of Congress expressed differing perspectives about the potential relationship between climate change and extreme events such as drought.
Fungal mating-type loci

Our studies are supported by grants from the NIH/NIAID, the Burroughs Wellcome Fund, and the Howard Hughes Medical Institute.
Isolation and characterization of wheat ω -gliadin genes

The DNA sequences of two full-length wheat ω-gliadin prolamin genes (ωF20b and ωG3) containing significant 5´ and 3´ flanking DNA sequences are reported. The ωF20b DNA sequence contains an open reading frame encoding a 30,460-Dalton protein, whereas the ωG3 sequence would encode a putative 39,210-Dalton protein except for a stop codon at amino-acid residue position 165. These two ω-gliadin genes are closely related and are of the ARQ-/ARE-variant type as categorized by the derived N-terminal amino-acid sequences and amino-acid compositions. The ω-gliadins were believed be related to the ω-secalins of rye and the C-hordeins of barley, and analyses of these complete ω-gliadin sequences confirm this close relationship. Although the ω-type sequences from all three species are closely related, in this analysis the rye and barley ω-type sequences are the most similar in a pairwise comparison. A comparison of ω-gliadin flanking sequences with respect to that of their orthologs and with respect to wheat gliadin genes suggests the conservation of flanking DNA necessary for gene function. Sequence data for members of all major wheat prolamin families are now available.
Neuronal transmission of timing precision: dependence on intrinsic and synaptic properties

Precision of spike timing and its role in information processing is one of the key themes in systems neuroscience. As signals travel through nervous systems, the precision and reliability of the timing information is altered. Interestingly, depending on the particular system, the timing precision can be improved or reduced through propagation. For example, at the transmission from auditory nerve to brainstem the emergence of latency precision and jitter reduction is observed [1]. On the other hand, phase locking to stimulus deteriorates across levels of auditory system from very good phase locking at early stages of processing in the brainstem to weaker phase locking in the midbrain (inferior colliculus) to an even weaker one in the auditory cortex [2]. This raises the issue of which properties allow for the improvement or deterioration of the timing information. Motivated by the processing of timing information in the auditory system, we examine the cellular and synaptic properties that affect improving or decreasing the precision of spike timing through synaptic transmission. We show through combination of analysis and numerics in minimal neuronal models (integrate-and-fire and Morris-Lecar) that both improvement and deterioration of spike-time precision through transmission is possible, depending on the input times distribution, number of inputs and synaptic strength. Further, in a conductance-based model we include more nuanced intrinsic and synaptic properties, in particular, currents that switch the neuron from integrator to coincidence detector (Prescott et al., 2006; Svirskis et al., 2004). We characterize response properties that deviate from the performance of an “ideal” integrator and coincidence detector in a manner dependent on details of the intrinsic ionic currents.
An evaluation of the McGill pain questionnaire for use in dental pain assessment

Abstract Pain following tooth extraction was assessed in 60 patients using the McGill Pain Questionnaire and the Anxiety Differential, along with other measures of patient expectations and behavior. The McGill Pain Questionnaire demonstrated efficacy in assessing postextraction pain with subscale measures relating to situational anxiety, recovery time and use of analgesics. Significant overlap among the subscales (7–58% common variance) was found suggesting further scale refinement is indicated. Pain descriptive words used and mean subscale scores were similar to those previously reported for toothache pain.
Solar energy, technology policy, and institutional values

Energy policies that promote new technologies and energy sources are policies for the future. They influence the shape of emergent technological systems, and also condition our social, political and economic lives. Solar Energy, Technology Policy, and Institutional Values demonstrates the difficulties of deliberating such properties by providing a historical case study that analyses US renewable energy policy from the end of World War II through the energy crisis of the 1970s. The book illuminates the ways beliefs and values come to dominate official problem frames and get entrenched in institutions. In doing so it also explains why advocates of renewable energy have often faced ideological opposition, and why policy makers fail to take them seriously.
Evaluation of the L5178Y mouse lymphoma cell mutagenesis assay: Intralaboratory results for sixty‐three coded chemicals tested at sri international

SRI used the L5178Y mouse lymphoma cell forward mutation assay to determine the mutagenic activity of 63 coded chemicals from 16 chemical classes. Replicate experiments were performed to assess the reproducibility of the assay within the laboratory. The evaluations (positive or negative) of the first two repeat experiments with the chemicals were the same for 116 (87%) of 134 tests. Evaluational differences between the first two experiments were fewer in the presence of induced S9 (6 tests) than in the absence of S9 (12 tests). The most commonly observed variability was the magnitude of positive mutagenic responses; this may be attributed to factors such as compound solubilities, S9 activation conditions, and differential recovery of mutant cells. Some consistency was observed in the responses of compounds of various chemical classes. Generally, antibiotics (ABO) and the azo dyes, azoxy and hydrazo compounds, diazoalkanes, nitriles and azides (AZO), were mutagenic with S9; alkyl, acyl, and aryl halides, halogenated ethers, and halohydrins (HAL) were more strongly mutagenic with than without S9; and monofunctional polycyclic aromatic hydrocarbons and fluorenones (PAH) were mutagenic only with S9. Amine-1-oxides (AMO), alkyl and aryl epoxides (EPO), and nitroalkanes, nitroaromatics, nitroquinolines, nitrofurans, and nitroimidazoles (NIT) were mutagenic with and without S9; amides, sulfonamides, aromatic amines, aliphatic amines, hydroxylamines, and benzidine and its derivatives (AMI) were mutagenic without S9; and methyl carbamate (the only monofunctional carbamate) and thioureas (CBM) induced a negative response under both conditions.
Purification, characterization, and glutathione binding to selenoprotein W from monkey muscle.

Abstract Selenoprotein W was purified from monkey skeletal muscle to investigate its binding of glutathione. The purification was accomplished by concentration of the cytosol with an Amicon cell, gel filtration using Sephadex G-50, cation-exchange chromatography with CM-Sephadex, and reverse-phase high-pressure liquid chromatography using a C-18 Vydac column. Selenoprotein W was monitored during purification by slot blots. These steps resulted in an electrophoretically pure selenoprotein W preparation that was estimated by gel filtration to have molecular weight of about 10 kDa. N-terminal amino acid sequencing was used to confirm that the pure proteins were selenoprotein W. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI) revealed that the proteins existed in three masses of 9635 ± 7, 9371 ± 11, and 9330 ± 5 Da. The theoretical mass of the protein predicted from the cDNA sequence is 9330 Da. The 9635-Da form of the protein was shown to contain bound glutathione (306 Da), which could be released by reduction with dithiothreitol at 50°C. The form with a mass of 9371 Da is assumed to result from binding of an unidentified 41-Da moiety to the 9330-Da form of the protein. MALDI peptide mapping with endoproteinase Glu-C suggested that glutathione is bound to the 36th amino acid (cysteine) of selenoprotein W.
A framework for addressing stochastic and combinatorial aspects of scheduling and resource allocation in pharmaceutical R&D pipelines

Abstract Managing a pharmaceutical R&D pipeline is a complex undertaking that involves an inter-play of strategic and tactical decision-making around portfolio selection, activity scheduling and resource allocation across multiple projects along a multi-year scope. In this paper we focus on improving the quality of pharmaceutical resource management decisions and practices. Pharmaceutical resource management is broadly comprised of decisions relating to scheduling and allocation of limited resources across development activities of multiple drug projects that are subject to technological and market uncertainties, long development cycle times as well as work process constraints. These complexities only magnify the risk of sub-optimal resource management. Notwithstanding this risk, the literature on joint optimization of scheduling and resource allocation decisions in the context of pharmaceutical R&D pipelines is limited. In this paper, a framework— SIM-OPT is proposed as an integrated resource management tool with the goals of maximizing the portfolio's expected net present value (ENPV), controlling risk and reducing drug development cycle times. The framework includes three key components: (1) a stochastic simulation of the pharmaceutical work flow process, (2) a ‘resource manager’ based on a mixed integer linear programming formulation that schedules and allocates resources as a function of demands from the simulated work process and (3) a ‘strategy learner’ that evaluates the impact of various resource strategies on the financial and cycle time performance of the simulated pipeline and draws key learnings. The output is a recommended set of resource management strategies and their impacts on expected return, risk and cycle time metrics. The effectiveness of the framework is demonstrated via its application to two industrial case studies drawn from a major pharmaceutical corporation. This approach offers potential benefits in terms of its ability to transform key learnings into efficient and reliable resource management practices that are well aligned with the overall business strategy.
Detection of weak link superconductivity by magnetically modulated electrical resistance

Abstract A new technique, based on observing the effect of magnetic field modulation on the DC resistance of superconductors, sensitively detects the presence of weak links in granular high temperature superconductors. The phase detected response to the magnetic modulation shows a peak at T c for both metallic and ceramic superconductors, analogous to that observed in magnetically modulated microwave absorption. A second peak, attributed to weak links, is observed below T c in the ceramic oxide superconductors when tailing is present in the resistance vs. temperature curve.
Histopathological changes in the temporal bone in kwashiorkor.

Histopathological changes in the temporal bone in kwashiorkor The histopathological changes in human temporal bones are described for 2 cases of kwashiorkor–a protein/calorie malnutrition (PCM) state. There is photographic evidence of severe damage to the middle and inner ears and to the vestibulocochlear nerve. The middle ear shows evidence of chronic otitis media, a common clinical finding in kwashiorkor. Significantly, the round window membranes in both cases showed thickening and infiltration with inflammatory cells. The inner ear showed the loss of cellular elements and hair cell loss in the spiral organ. A marked decrease of spiral ganglion cells and demyelination of the vestibulocochlear nerve were also seen.
Insulin Enhances Development of Functional Voltage-Dependent Ca2+ Channels in Aneurally Cultured Human Muscle

Voltage-dependent Ca2+ channels were studied by the binding of the potent Ca2+ channel antagonist PN200-110 and by the K+-induced 45Ca2+ uptake in human muscle cultured aneurally in the presence of insulin, fibroblast growth factor, and epidermal growth factor, added in combination or individually. Compared to the muscle grown in medium without growth factors, 14-15 days of treatment with insulin (10 micrograms/ml) alone or in combination with two other growth factors caused a 3.4- and 3.8-fold increase per culture dish in the number of PN200-110 binding sites, respectively. There was no change in the affinity of the ligand-receptor complex. Under the same conditions, there was also fourfold increase of the K+-induced 45Ca2+ uptake in cultured human muscle. Neither fibroblast growth factor nor epidermal growth factor alone influenced PN200-110 binding sites. Our study demonstrates that insulin enhances the development of functional voltage-dependent Ca2+ channels in cultured human muscle.
Intermediate-term outcomes of endovascular treatment for symptomatic chronic mesenteric ischemia.

Objective Endovascular therapy for chronic mesenteric ischemia (CMI) has been increasingly utilized. Early outcomes compare favorably with open mesenteric bypass—the current gold standard. The goal of this study is documentation of intermediate-term anatomic and functional outcomes of endovascular mesenteric revascularization for symptomatic CMI. Methods This is a retrospective review of all patients undergoing endovascular treatment of symptomatic CMI from July 2002 to March 2008. Study endpoints included periprocedural mortality, major morbidity, patency, symptomatic recurrence, and survival. Endpoints were analyzed using actuarial methods. Results Sixty-six mesenteric arteries (78.8% stenotic/21.2% occluded) were treated in 49 patients. One or more vessels were treated in each case; however, four mesenteric artery total occlusions (3 SMAs/1 IMA) could not be crossed. Initial symptom relief was noted in 89.8% (n = 44) with no change in 5 patients. Single-vessel treatments were performed in 32 patients (65.3%) and two-vessel interventions in 17 (34.7%). The 30-day mortality rate was 2.0% (n = 1). Major complications occurred in 8 patients (16.3%). The mean follow-up duration was 37.4 ± 2.98 months (range, 0-66). Restenosis on follow-up imaging occurred in 64.9% (n = 24) of the 37 patients who had radiographic surveillance at a mean follow-up interval of 8.5 ± 1.9 months and was diagnosed most often by Duplex scan or computed tomographic angiography (CTA). Fourteen patients (28.6%) developed recurrent symptoms with 13 requiring a reintervention. Actuarial 36-month freedom from symptomatic recurrence was 60.9% ± 9.4%. Two-vessel treatment was protective against symptom recurrence (P = .0014) and reintervention (P = .0060) by univariate analysis. A total of 19 reinterventions were required in 14 patients (28.6%) at a mean of 17 months from the original treatment. Primary patency at 36 months was 63.9 ± 8.5%. Actuarial survival at 48 months was 81.1% ± 6.1% with no CMI-related deaths in the study cohort. Conclusion Intermediate (3-year) follow-up indicates that significant restenosis and symptom recurrence are common following the endovascular treatment of symptomatic CMI. Thirty percent of the cohort required a reintervention, one-third of which were conversions to surgical reconstruction. Similar to the surgical paradigm of two-vessel revascularization, endovascular treatment of multiple mesenteric arteries produced better outcomes. A first-line endovascular approach to patients with CMI is a reasonable clinical strategy, but close follow-up is mandatory.
Grafts of fibroblasts genetically modified to secrete NGF, BDNF, NT-3, or basic fgf elicit differential responses in the adult spinal cord

Neuronal and axonal responses to neurotrophic factors in the developing spinal cord have been relatively well characterized, but little is known about adult spinal responses to neurotrophic factors. We genetically modified primary rat fibroblasts to produce either nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), or basic fibroblast growth factor (bFGF), then grafted these neurotrophic factor-secreting cells into the central gray matter of the spinal cord in adult rats. Spinal cord lesions were not made prior to grafting. From 2 wk to 6 mo later, sensory neurites of dorsal root origin extensively penetrated NGF-, NT-3-, and bFGF-producing grafts, whereas BDNF-secreting grafts elicited no growth responses. Putative noradrenergic neurites also penetrated NGF-secreting cell grafts. Local motor and corticospinal motor axons did not penetrate any of the neurotrophic factor-secreting grafts. These results indicate that unlesioned or minimally lesioned adult spinal cord sensory and putative noradrenergic populations retain significant neurotrophic factor responsiveness, whereas motor neurites are comparatively resistant even to those neurotrophic factors to which they exhibit survival dependence during development. Grafts of genetically modified cells can be a useful tool for characterizing neurotrophic factor responsiveness in the adult spinal cord and designing strategies to promote axonal regeneration after injury.
Cystic adventitial disease of the popliteal artery.

A53-year-old man presented with intermittent claudication of his right leg and a painless walking distance of about 120 meters. On examination there were no stigmata of generalized arterial disease. The peripheral pulses were present with the limb extended but disappeared during knee joint flexion. Color-coded Doppler sonography resulted in the diagnosis of a high-grade stenosis of the supragenicular popliteal artery, which was confirmed by magnetic resonance angiography (Figure 1), demonstrating the scimitar sign, a curvilinear defect marking an eccentrically located, smoothly demarcated stenosis in an otherwise normal artery. Axial magnetic resonance imaging (Figure 2) revealed a cystic lesion (straight arrows) nearly occluding the popliteal arterial lumen (curved arrow). The high signal intensity on T1-weighted images suggested a rather high protein content of this lesion. Because of the typical location and clinical signs, cystic adventitial disease was suspected. At operation, after the popliteal artery had been exposed via a posterior approach, cystic advential disease was confirmed by the presence of its pathognomonic features. The arterial caliber showed a circumscribed enlargement, from which, on longitudinal incision, a yellowish-colored, pressurized, gelatinous, viscid, mucoid mass escaped (Figure 3). The adventitial layer was completely resected, preserving the arterial continuity and thereby restoring flow (Figure 4). No connection with the knee joint could be demonstrated in this case. After an uneventful postoperative course the patient is free of symptoms with a follow-up of 28 months.
Feature-based representational scheme of a solid modeler for providing dimensioning and tolerancing information

Abstract Presently available CAD data models have no problem handling the basic shape design of an object as required but they are not properly manufacturing-oriented. It is not possible to represent the dimensioning and tolerancing information or other technological information (such as material data, the surface roughness and accuracy data, feature information, etc.). This paper discusses the requirements of a new CAD data model and proposes a feature-based representation scheme based on the hybrid CSG/B-Rep data structure. This hybrid structure exploits the advantages of both CSG and B-Rep models in representing tolerance information. A relational graph structure (face-based data model of B-Rep) of the object is maintained at each hierarchical level of object construction for associating tolerance and other attributes.
Gender Differences in High-school Students' Views about Science

This study examined gender differences in 79 high‐school students’ attitudes towards their science classes, their perceptions of science and scientists, and their views about majoring in science. The study identified some of the subtleties underlying females’ low participation in, and interest in, science documented in previous research. Four themes emerged from responses on the rating scales and questionnaire. First, even when females planned to major in science, they were more interested than males in the people‐oriented aspects of their planned majors. Second, biology was the one exception to females’ low interest in science. Third, females often planned a science major mainly because they needed a science background in order to enter a health profession such as medicine or physical therapy. Fourth, females generally found science uninteresting and the scientific lifestyle (as perceived by them) unattractive. Implications for teaching science were discussed.
Intrinsic viscosity of polydisperse branched polymers

The relationships between molecular weight distribution and structure in polymerizations with long-chain branching were reviewed and extended. Results were applied to an experimental examination of intrinsic viscosity in polydisperse, trifunctionally branched systems. Several samples of poly(vinyl acetate) were prepared by bulk polymerization under conditions of very low radical concentration. The relative rate constants for monomer transfer, polymer transfer, and terminal double-bond polymerization were established from the variation of Mn and Mw with the extent of conversion. Average branching densities were then calculated for each sample and ranged as high as 1.5 branch points/molecule. Intrinsic viscosities [η]B were measured in three systems: a theta-solvent, a good solvent, and one that was intermediate in solvent interaction. These results were compared with calculated viscosities, [η]L, which would have been observed if all the molecules had been linear. The values of [η]B/[η]L were substantially the same in all three solvents. The variation of this ratio with branching density was compared with the theory of Zimm and Kilb as adapted to polydisperse systems. Discrepancies were noted, and the adequacy of present model distribution functions for branched polymers was questioned.
Effect of metabolic acidosis on branched-chain amino acids in uremia.

Fasting plasma concentrations of branched-chain amino acids (BCAA) valine, leucine, and isoleucine were measured in 20 young patients (aged 18±2 years) with end-stage renal disease just before initiation of dialysis and compared with 7 healthy controls (aged 19±1 years). Plasma valine, leucine, and isoleucine were all lower than control values (P<0.01 in all 3 cases). Plasma valine, but not leucine and isoleucine, correlated with venous pH (P<0.02). Plasma valine, leucine, or isoleucine did not correlate with blood urea nitrogen or serum creatinine. Seven patients (aged 18±1 years) on maintenance hemodialysis with metabolic acidosis were then studied before and after 2 weeks of oral sodium bicarbonate (NaHCO3) treatment to correct the acidosis. To control for the effect of additional sodium, they were also studied after 2 weeks of an equivalent amount of oral sodium chloride (NaCl). Oral NaHCO3 treatment led to significant increases in venous pH and serum bicarbonate concentrations, but no significant change in total and ionized calcium, phosphate, sodium, potassium, creatinine, blood urea nitrogen, and intact parathyroid hormone concentrations. Oral NaCl did not change any of the biochemical parameters. Fasting plasma concentrations of BCAA were measured. Before treatment of acidosis, uremic patients had low plasma concentrations of valine, leucine, and isoleucine compared with controls. Following 2 weeks of NaHCO3 treatment, there were significant increases in the plasma concentrations of valine and leucine (P<0.01), although the values did not normalize. There were no changes in plasma concentrations of valine and leucine following 2 weeks of NaCl. The plasma concentration of isoleucine was not different during baseline (acidotic) and treatment periods with NaHCO3 and NaCl. Thus treatment of metabolic acidosis ameliorated abnormalities in plasma concentrations of valine and leucine in patients with uremia on hemodialysis.
Potential Vorticity of the Madden-Julian Oscillation

AbstractThis study explores the extent to which the dynamical structure of the Madden–Julian oscillation (MJO), its evolution, and its connection to diabatic heating can be described in terms of potential vorticity (PV). The signature PV structure of the MJO is an equatorial quadrupole of cyclonic and anticyclonic PV that tilts westward and poleward. This PV quadrupole is closely related to positive and negative anomalies in precipitation that are in a swallowtail pattern extending eastward along the equator and splitting into off-equatorial branches westward. Two processes dominate the generation of MJO PV. One is linear, involving MJO diabatic heating alone. The other is nonlinear, involving diabatic heating and relative vorticity of perturbations spectrally outside the MJO domain but spatially constrained to the MJO convective envelope. The MJO is thus partially a self-sustaining system and partially a consequence of scale interaction of MJO-constrained stochastic processes. Convective initiation of th...
Speech analysis and segmentation by parametric filtering

A new set of digital signal processing techniques for detecting changes in a speech signal is considered. The overall approach is called parametric filtering, and it yields several promising new diagnostics for speech analysis and segmentation including in particular, the demodulated lag-one autocorrelation /spl gamma//sub /spl theta//(/spl eta/), the time-correlation analysis plot, and the /spl gamma//sub /spl theta//(/spl eta/)-based distortion measures. Initial experiments described in this paper establish the potential significance of the parametric filtering method and these new diagnostics for speech analysis and segmentation.
Behavioral and histopathological effects of fluoranthene on bullfrog larvae (Rana catesbeiana)

Amphibians are potentially sensitive indicator organisms of environmental stress because of their permeable skins and biphasic life cycles. The goals of this study were to use behavioral and histopathological endpoints to examine the sublethal effects of fluoranthene exposure in conjunction with solar ultraviolet radiation on bullfrog larvae. Exposure to fluoranthene and simulated solar ultraviolet radiation for 48 h caused a significant effect on locomotor behavior at 60 {micro}g fluoranthene/L. At 96 h, however, hyperactivity was noted in the 40-{micro}g fluoranthene/L exposure. The skin of bullfrog larvae was sensitive to the phototoxic effects of fluoranthene. Following exposure to sublethal levels of fluoranthene there were signs of necrosis as well as structural alterations in the skin when examined using light microscopy. Based on these results, the photoinduced toxicity of fluoranthene, and hence other phototoxic polycyclic aromatic hydrocarbons, pose a potential hazard to ranid larvae well within the water solubility limits of the compound.
Reduced-order modeling of Markov and hidden Markov processes via aggregation

In this paper we study the problem of approximating a Markov process with a large number of states by another one with fewer states. While there are many ways to do this, we focus on a method known as ‘aggregation’, that is, combining states of the original Markov process in an attempt to reduce the size of the state space. The problem of ‘optimal’ aggregation is formulated as one of minimizing the relative entropy rate between the two Markov processes, using the results in a companion paper. An exact solution to the optimization problem is intractable, as it requires one to solve a combinatorial optimization problem. As an alternative, we present a heuristic that is quite feasible and produces sub-optimal aggregations. The same approach is then extended to hidden Markov models. At present there is no closed-form formula for the relative entropy rate (or Kullback-Leibler) divergence rate between two hidden Markov processes. Hence we study instead the joint state and output process, which is Markov, and aggregate that instead. In such an approach, the resulting aggregated process is in general not a joint process, and even if it is, it is not a hidden Markov process. So we suggest a procedure for ensuring that the aggregated process is indeed a hidden Markov process.
Temperature-sensitive TREK currents contribute to setting the resting membrane potential in embryonic atrial myocytes.

TREK channels belong to the superfamily of two-pore-domain K+ channels and are activated by membrane stretch, arachidonic acid, volatile anaesthetics and heat. TREK-1 is highly expressed in the atrium of the adult heart. In this study, we investigated the role of TREK-1 and TREK-2 channels in regulating the resting membrane potential (RMP) of isolated chicken embryonic cardiac myocytes. At room temperature, the average RMP of embryonic day (ED) 11 atrial myocytes was −22 ± 2 mV. Raising the temperature to 35°C hyperpolarized the membrane to −69 ± 2 mV and activated a large outwardly rectifying K+ current that was relatively insensitive to conventional K+ channel inhibitors (TEA, 4-AP and Ba2+) but completely inhibited by tetracaine (200 μm), an inhibitor of TREK channels. The heat-induced hyperpolarization was mimicked by 10 μm arachidonic acid, an agonist of TREK channels. There was little or no inwardly rectifying K+ current (IK1) in the ED11 atrial cells. In marked contrast, ED11 ventricular myocytes exhibited a normal RMP (−86.1 ± 3.4 mV) and substantial IK1, but no temperature- or tetracaine-sensitive K+ currents. Both RT-PCR and real-time PCR further demonstrated that TREK-1 and TREK-2 are highly and almost equally expressed in ED11 atrium but much less expressed in ED11 ventricle. In addition, immunofluorescence demonstrated TREK-1 protein in the membrane of atrial myocytes. These data indicate the presence and function of TREK-1 and TREK-2 in the embryonic atrium. Moreover, we demonstrate that TREK-like currents have an essential role in determining membrane potential in embryonic atrial myocytes, where IK1 is absent.
Research Needed to Support Clinical Use of Biomarkers as Prognostic Indicators for Patients with Heart Failure

Despite extensive research and numerous publications biomarkers have yet to fulfill their promise as prognostic indicators that can be widely used in the care of patients with heart failure. Specific clinical applications need to be identified for informative analyses of data that emphasize the most directly applicable measures of predictive performance.
Origin of ruffles: Linkage to other protrusions, filopodia and lamellae

Abstract Although growth factor-initiated cascades in cells are networked with mechanisms such as “inside-out signaling”, it is not known how these pathways are integrated. Earlier studies reported that ruffling was enhanced and filopodia reduced in transformed cells. Since dissecting relationships among features was impossible if subjective recognition was relied upon, features in two epithelial cell lines were recognized by latent factor analysis. Factor-based classification revealed four protrusion classes, but none of them corresponded to ruffles. Loss of filopodia, defined by factor 4 (F4) values, accounted for the greatest change in features of oncogenically transformed cells. Factor 5 (F5, lamella) was unchanged during transformation of an airway epithelium cell line. The tumor promoter, phorbol 12-myristate 13-acetate (PMA), increased ruffling but decreased filopodia. F4 retained this relationship to ruffling in untreated cells and at multiple times after treatment. F5 values decreased but were positively correlated with measures of ruffling. Because factors are created as mutually orthogonal variables, this suggested that ruffles were not flagged in factor analysis because they originate from other features. Actin filament capping with sub-micromolar cytochalasin D (Cyto D) suppressed ruffling without affecting F4 or F5. Cyto D increased factor 7 (F7) values, thus showing specificity for this feature. However, cytochalasin treatment of PMA-treated cells that had developed stress fibers increased F4 and decreased F5. The results suggest that PMA changes the state of the cytoskeleton, causing protrusions to show novel responses to Cyto D compared to untreated cells. Results suggest that the factors identify physiologically distinct features.
Group Theory of the Spontaneously Broken Gauge Symmetries

The patterns of symmetry breaking in the gauge theories are investigated systematically in the general rotation groups and unitary groups, with Higgs scalars in the various representations up to second-rank tensors. The occurrences of the fermion mass relations and pseudo-Goldstone bosons are also discussed in various cases.
Can Legacy Systems Beget Product Lines

In many respects it is easier to formulate an architecture for a family of products if one assumes that the systems are being developed from scratch. But the vast majority of systems development efforts today start from a cornucopia of legacy systems. Significant progress in component-based architecture, system understanding, object-technology, and net-centric computing now makes it possible to evolve these legacy systems to a state in which they exhibit many of the characteristics of product lines. Systems in well-established domains are migrating to distributed object systems that exhibit large-scale reuse from a core set of assets while keeping the legacy systems largely intact. Many of these systems have evolved without overtly using product line terminology or practices and have been off the radar screen of the product line community as a starting point for product families. The advocates of product lines need to recognize this "distributed legacy evolution model" as an integral part of their practices for developing information systems.
Social welfare functions that satisfy Pareto, anonymity, and neutrality, but not independence of irrelevant alternatives

In the presence of Pareto, non-dictatorship, full domain, and transitivity, an extremely weak independence condition disallows both anonymity and neutrality.
Alloy solidification in systems containing a liquid miscibility gap

Directional solidification methods have been used to examine the growth of fibrous, or tubular, composite samples in alloys close to the monotectic reaction: Liquid 1 Solid + Liquid 2. The binary systems Al-In, Cu-Pb and Cd-Ga have been examined and some use made of a transparent analogue, succinnonitrile-water. The solidification behavior appears to relate to the height of the miscibility gap in such systems and it is demonstrated how ternary additions which change this height (Sn to Al-In, Al to Cu-Pb) modify the microstructures dramatically. These structural changes are discussed with reference to the relative surface energies between two immiscible liquids and a third (solid) phase. The phase spacings and transitions in microstructure are discussed in terms of diffusion processes at the monotectic front.
A comparative approach for the investigation of biological information processing: an examination of the structure and function of computer hard drives and DNA.

Background: The robust storage, updating and utilization of information are necessary for the maintenance and perpetuation of dynamic systems. These systems can exist as constructs of metal-oxide semiconductors and silicon, as in a digital computer, or in the “wetware” of organic compounds, proteins and nucleic acids that make up biological organisms. We propose that there are essential functional properties of centralized information-processing systems; for digital computers these properties reside in the computer’s hard drive, and for eukaryotic cells they are manifest in the DNA and associated structures. Methods: Presented herein is a descriptive framework that compares DNA and its associated proteins and sub-nuclear structure with the structure and function of the computer hard drive. We identify four essential properties of information for a centralized storage and processing system: (1) orthogonal uniqueness, (2) low level formatting, (3) high level formatting and (4) translation of stored to usable form. The corresponding aspects of the DNA complex and a computer hard drive are categorized using this classification. This is intended to demonstrate a functional equivalence between the components of the two systems, and thus the systems themselves. Results: Both the DNA complex and the computer hard drive contain components that fulfill the essential properties of a centralized information storage and processing system. The functional equivalence of these components provides insight into both the design process of engineered systems and the evolved solutions addressing similar system requirements. However, there are points where the comparison breaks down, particularly when there are externally imposed information-organizing structures on the computer hard drive. A specific example of this is the imposition of the File Allocation Table (FAT) during high level formatting of the computer hard drive and the subsequent loading of an operating system (OS). Biological systems do not have an external source for a map of their stored information or for an operational instruction set; rather, they must contain an organizational template conserved within their intra-nuclear architecture that “manipulates” the laws of chemistry and physics into a highly robust instruction set. We propose that the epigenetic structure of the intra-nuclear environment and the non-coding RNA may play the roles of a Biological File Allocation Table (BFAT) and biological operating system (Bio-OS) in eukaryotic cells.
Recent Advances of Structural Life Assessment and Related Problems

Structural life assessment (SLA) is a diversified field and is based on the theories of fracture mechanics, fatigue damage process, probability of failure and reliability. SLA is not only governed by the theory of fracture mechanics and fatigue damage process, but by the type of loading. The theory of fracture mechanics may be classified into quasi-static fracture mechanic and dynamic fracture mechanics. The problem of singularity encountered in fracture mechanics has been resolved by the new theory of peridynamics described by integro-differential equation of motion. The basic ingredients of the theory of fracture mechanics will be presented in terms of linear elastic fracture mechanics (LEFM) and elasto-plastic fracture mechanics (EPFM) , dynamic fracture mechanics and peridynamics. The amount of energy available for fracture is usually governed by the stress field around the crack, which is measured by the stress intensity factor. SLA depends on the failure modes and the probabilistic description of failure.
Intersectionality in Electoral Politics: A Mess Worth Making

Prior to the recent reauthorization of the Voting Rights Act of 1965, I was involved in numerous conversations regarding strategies for its renewal. These conversations prompted me to reflect not only on the impact of the Voting Rights Act for African-American citizenship but in particular on the ways in which it did for African-American women what the Constitution and its amendments had previously failed to do. After all, it is not until the passage of this legislation that African-American women are first extended a modicum of citizenship in the United States.
Directional interpolation of images based on visual properties and rank order filtering

The goal of this research is to develop interpolation techniques which preserve or enhance the local structure critical to image quality. Preliminary results are presented which exploit either the properties of vision or the properties of the image in order to achieve the goals. Directional image interpolation is considered which is based on a local analysis of the spatial image structure. The extension of techniques for the design of linear filters based on properties of human perception reported previously to enhance the perceived quality of interpolated images is considered. >
State synchronization in local-interaction networks is robust with respect to time delays

This is among the first results that suggest that multi-agent systems that interact through time-invariant, nearest-neighbor rules, can synchronize their states regardless of the size of communication delays. Network connectivity and consistency in the use of neighbor state information is all that is needed. The analysis in this paper is performed in discrete time and is based on the properties of non-negative matrices. Due to the fact that the state transition matrix is no more ergodic, the results of [1] cannot be applied. A crucial observation regarding the delayed dynamics allows the reduction of the model and the establishment of ergodicity for the system’s state transition matrix.
Excitation-emission matrix fluorescence based determination of carbamate pesticides and polycyclic aromatic hydrocarbons

Abstract The ability to accurately quantitate trace pesticides and polycyclic aromatic hydrocarbons (PAHs) by excitation–emission matrix (EEM) fluorescence spectroscopy, when coupled with parallel factor analysis (PARAFAC) deconvolution of the EEM spectra, is demonstrated and discussed. Two EEM fluorometers were investigated. One fluorometer, using a cuvette cell sample holder, realized limits of detection of 1.1, 6.6, and 13 ppb for 1-naphthol, carbaryl, and carbofuran in methanol mixtures, respectively. 0.2 ppb limits of detection were also observed for three PAHs. With this fluorometer, the PARAFAC model was employed to resolve the analyte spectra from overlapping fluorescence signals and Raman scattering profiles. Employing a second fluorometer with a fiber-optic probe for remote sampling yielded 10–30 ppb limits of detection for 9 PAHs. The PARAFAC model was required here to resolve the PAH spectra from the instrumental background.
The non-impulsive stretch-receptor complex of the crab: a study of depolarization--release coupling at a tonic sensorimotor synapse.

A new preparation for the study of synaptic transmission is described from the thoracic ganglion of the crab Callinectes sapidus . The central anatomy of the nonimpulsive stretch-receptor neurons of the thoracic-coxal joint and that of the promotor motoneurons with which they form synaptic junctions was studied with intracellular cobalt staining and light and electron microscopy. Attention was centred on the interaction of the stretch-receptor T-fibre and the four large motoneurons supplying the promotor muscle which have their cell-bodies on the dorsal surface of the ganglion. The presynaptic terminal region of the T-fibre appeared to be a simple cylinder in form with a diameter of 40-60 μm and containing large stores of synaptic vesicles at its periphery, opposite the complex of motoneuron dendrites. The transmission characteristics of the junctions between receptor cell and motoneurons were studied by transmembrane current injection into the isolated T-fibre by means of a sucrose gap and simultaneous intracellular recording with microelectrodes from the presynaptic terminal and the somata of postsynaptic cells. It was shown that depolarization-release coupling in the T-fibre has similar properties to those that have been demonstrated in the squid giant synapse, with the same values for ‘threshold’, peak release and ‘suppression potential’. The crab synapses differ from that of the squid in that they normally transmit prolonged, graded depolarizations (i.e. receptor potentials) which are decrementally conducted from the periphery. Consistent with this role, the junctions were found to be capable of continuous tonic transmission over many seconds without the strong depletion seen in more phasic synapses. In a study of the relation between the synaptic properties and the stretch reflex it was shown that some of the time- and amplitude-dependent behaviour of the overall reflex can be encoded at the level of the synaptic transmission, largely through the parameter of transmitter availability. Conduction of electrical signals in the proximal and presynaptic part of the sensory fibre was also investigated. Transient responses to step depolarizing currents in the fibre indicate the existence of a mechanism for the partial compensation of capacitative distortion in the decrementally conducted receptor potential. This is the first example of intracellular recording from presynaptic terminals of nonimpulsive neurons with simultaneous monitoring of postsynaptic potential changes, allowing for a direct analysis of depolarization-release coupling characteristics. The use of the preparation for further study of synaptic physiology and sensorimotor systems is discussed.