cssi/SciSciGPT-SciSciNet huggingface dataset:
Regulation of Epithelial Na+ Transport by Soluble Adenylyl Cyclase in Kidney Collecting Duct Cells

Alkalosis impairs the natriuretic response to diuretics, but the underlying mechanisms are unclear. The soluble adenylyl cyclase (sAC) is a chemosensor that mediates bicarbonate-dependent elevation of cAMP in intracellular microdomains. We hypothesized that sAC may be an important regulator of Na+ transport in the kidney. Confocal images of rat kidney revealed specific immunolocalization of sAC in collecting duct cells, and immunoblots confirmed sAC expression in mouse cortical collecting duct (mpkCCDc14) cells. These cells exhibit aldosterone-stimulated transepithelial Na+ currents that depend on both the apical epithelial Na+ channel (ENaC) and basolateral Na+,K+-ATPase. RNA interference-mediated 60-70% knockdown of sAC expression comparably inhibited basal transepithelial short circuit currents (Isc) in mpkCCDc14 cells. Moreover, the sAC inhibitors KH7 and 2-hydroxyestradiol reduced Isc in these cells by 50-60% within 30 min. 8-Bromoadenosine-3′,5′-cyclic-monophosphate substantially rescued the KH7 inhibition of transepithelial Na+ current. Aldosterone doubled ENaC-dependent Isc over 4 h, an effect that was abolished in the presence of KH7. The sAC contribution to Isc was unaffected with apical membrane nystatin-mediated permeabilization, whereas the sAC-dependent Na+ current was fully inhibited by basolateral ouabain treatment, suggesting that the Na+,K+-ATPase, rather than ENaC, is the relevant transporter target of sAC. Indeed, neither overexpression of sAC nor treatment with KH7 modulated ENaC currents in Xenopus oocytes. ATPase and biotinylation assays in mpkCCDc14 cells demonstrated that sAC inhibition decreases catalytic activity rather than surface expression of the Na+,K+-ATPase. In summary, these results suggest that sAC regulates both basal and agonist-stimulated Na+ reabsorption in the kidney collecting duct, acting to enhance Na+,K+-ATPase activity.
THE FOOD OF THE PINE MARTEN MARTES MARTES IN WEST ROSS‐SHIRE, SCOTLAND

This paper concerns the food of the pine marten Marles martes in the Beinn Eighe National Nature Reserve, West Ross-shire, between 1956 and 1958. The technique of studying food from droppings and the need for correction factors are discussed. The study is based on 337 droppings. The food eaten was varied both in size and nature but small rodents and small birds formed the bulk of the food at all times of the year. Coleoptera, Lepidoptera, carrion, fish and berries were eaten seasonally. Small prey appeared to be preferred. Ninety per cent of the small rodents eaten were short-tailed voles Microtus agrestis despite the fact that bank voles Clethrionomys glareolus and woodmice Apodemus sylvaticus were probably more abundant and the martens' activity rhythm brought them into contact with all three species.
Evolution of the miR-290–295/miR-371–373 Cluster Family Seed Repertoire

Expression of the mouse miR-290–295 cluster and its miR-371–373 homolog in human is restricted to early embryos, primordial germ cells, the germ line stem cell compartment of the adult testis and to stem cell lines derived from the early embryonic lineages. Sequencing data suggest considerable seed diversification between the seven homologous pre-miRNAs of miR-290–295 but it is not clear if all of the implied miR-290–295 seeds are also conserved in the human miR-371–373 cluster, which consists of only three homologous pre-miRNAs. By employing miRNA target reporters we show that most, if not all, seeds in miR-290–295 are represented in miR-371–373. In the mouse, pre-miR-290, pre-miR-292 and pre-miR-293 express subsets of the miRNA isoforms processed from the single human pre-miR-371. Comparison of the possible miR-290–295/miR-371–373 seed repertoires in placental mammals suggests a model for the evolution of this miRNA cluster family, which would be otherwise difficult to deduce based solely on pre-miRNA sequence comparisons. The conservation of co-expressed seeds that is characteristic of miR-290–295/miR-371–373 should be taken into account in models of the corresponding miRNA-target interaction networks.
Dystroglycan: Emerging Roles in Mammary Gland Function

Dystroglycan (DG) is a single receptor that binds to multiple basement membrane proteins and forms a transmembrane link to the actin cytoskeleton. It was first isolated as a component of the dystrophin–glycoprotein complex, which plays a role in the maintenance of muscle cell integrity and is defective in many muscular dystrophies. Although studied most extensively in muscle tissues, DG is present at most cell–basement membrane interfaces, and only recently has investigation of DG functions in nonmuscle cells gained momentum. Information emerging from recent studies in epithelial cells is implicating DG in a wide range of critical cell responses to the basement membrane, ranging from organization of tissue architecture to cell survival. Moreover, DG functions appear to be frequently absent in carcinoma cells, implicating its loss in cancer progression. Although many questions remain as to its precise role in mammary tissue, DG is emerging as a potentially important player in mammary gland function.
Design, synthesis, and evaluation of carbamate-substituted analogues of (+)-discodermolide.

The design, syntheses, and biological evaluation of 22 totally synthetic analogues of the potent microtubule-stabilizing agent (+)-discodermolide (1) have been achieved. Structure−activity relationships of the C(19) carbamate were defined, exploiting two synthetically simplified scaffolds, as well as the parent (+)-discodermolide framework.
Achieving synaptically relevant pulses of neurotransmitter using PDMS microfluidics.

Abstract Fast synaptic transmission is mediated by post-synaptic ligand-gated ion channels (LGICs) transiently activated by neurotransmitter released from pre-synaptic vesicles. Although disruption of synaptic transmission has been implicated in numerous neurological and psychiatric disorders, effective and practical methods for studying LGICs in vitro under synaptically relevant conditions are unavailable. Here, we describe a novel microfluidic approach to solution switching that allows for precise temporal control over the neurotransmitter transient while substantially increasing experimental throughput, flexibility, reproducibility, and cost-effectiveness. When this system was used to apply ultra-brief (∼400 μs) GABA pulses to recombinant GABA A receptors, members of the cys-loop family of LGICs, the resulting currents resembled hippocampal inhibitory post-synaptic currents (IPSCs) and differed from currents evoked by longer, conventional pulses, illustrating the importance of evaluating LGICs on a synaptic timescale. This methodology should therefore allow the effects of disease-causing mutations and allosteric modulators to be evaluated in vitro under physiologically relevant conditions.
Extraction of 1-methylnaphthalene and m-cresol with supercritical carbon dioxide and ethane

Extraction equilibrium of two liquids (1-methylnaphthalene and m-cresol) separately with two supercritical solvents (carbon dioxide and ethane) are determined in a semi-flow apparatus at three temperatures (308, 318 and 328 K) and pressures to 240 bar.
A reactive molecular dynamics study of the thermal decomposition of perfluorodimethyl ether.

Classical reactive molecular dynamics (RMD) simulation is used to model the thermal decomposition of perfluorodimethyl ether (CF3OCF3), which is relevant as a simple molecule containing the necessary architectural elements to study the chemical stability of perfluoropolyether lubricants. The RMD algorithm employs nonreactive interaction potentials for the reactants and products. The reactivity is implemented through a coarse-grained simulation algorithm, incorporating elements from both the quantum and macroscopic descriptions of the reaction. The RMD scheme maps the quantum mechanically determined transition state onto a set of geometric triggers. When a configuration matching those triggers is found in the RMD simulation, the reaction instantaneously occurs. A brief, local equilibration process stabilizes the configuration, and the simulation continues. Using two geometric triggers, the RMD simulation can describe quantitatively the temperature dependence of the thermal decomposition of CF3OCF3, when co...
The effect of human pattern-recognition abilities in improving DSS performance

In this paper, the function of a data-centred decision-support system (DSS) is simulated to investigate whether the incorporation of human pattern-recognition abilities significantly improves the performance of a system. Two decision making scenarios are considered. In one scenario, there is no human interaction, whereas the other scenario uses the pattern-recognition capabilities of humans. The simulation is performed by mining 10,000 records in 980 replications. The DSS has the ability to take corrective actions with the purpose of keeping the incoming data records within a given set of upper and lower boundaries. The results indicate that incorporating pattern-recognition ability in a DSS significantly improves the system's performance. However, the impact of human input is not linear with respect to system performance. Our study shows that a moderate degree of human intervention will usually provide the greatest positive impact on the system's performance.
The RecA Protein as a Model Molecule for Molecular Systematic Studies of Bacteria: Comparison of Trees of RecAs and 16S rRNAs from the Same Species.

The evolution of the RecA protein was analyzed using molecular phylogenetic techniques. Phylogenetic trees of all currently available complete RecA proteins were inferred using multiple maximum parsimony and distance matrix methods. Comparison and analysis of the trees reveal that the inferred relationships among these proteins are highly robust. The RecA trees show consistent subdivisions corresponding to many of the major bacterial groups found in trees of other molecules including the alpha, beta, gamma, delta, epsilon proteobacteria, cyanobacteria, high-GC gram-positives, and the Deinococcus-Thermus group. However, there are interesting differences between the RecA trees and these other trees. For example, in all the RecA trees the proteins from gram-positive species are not monophyletic. In addition, the RecAs of the cyanobacteria consistently group with those of the high-GC gram-positives. To evaluate possible causes and implications of these and other differences phylogenetic trees were generated for small-subunit rRNA sequences from the same (or closely related) species as represented in the RecA analysis. The trees of the two molecules using these equivalent species-sets are highly congruent and have similar resolving power for close, medium, and deep branches in the history of bacteria. The implications of the particular similarities and differences between the trees are discussed. Some of the features that make RecA useful for molecular systematics and for studies of protein evolution are also discussed.
The use of 129I as an isotopic tracer and its determination along with normal 127I by neutron activation—The isolation of iodine from a variety of materials

Abstract In order to make the 1·7 × 107 year 129I useful as an iodine tracer a neutron activation procedure was used for its determination. A procedure involving high temperature ignition in a stream of oxygen was devised for the isolation of iodine from a variety of materials. After activation and decontamination a large sodium iodide, well-type crystal was used as a selective detector for the 130I activation product. The normal iodine content of a sample is readily determined at the same time.
Differing in vitro Survival Dependency of Mouse and Rat NG2+ Oligodendroglial Progenitor Cells

NG2 chondroitin sulfate proteoglycan is a surface marker of oligodendroglial progenitor cells (OPCs) in various species. In contrast to well-studied rat OPCs, however, we found that purified mouse NG2 surface positive cells (NG2+ cells) require additional activation of cyclic AMP (cAMP) signaling for survival in a medium containing 30% B104 neuroblastoma conditioned medium supplemented with fibroblast growth factor-2 (B104CM+FGF2), whereas B104CM+FGF2 alone is sufficient for survival and selective proliferation of rat OPCs. After induction of in vitro differentiation, more than 90% of mouse NG2+ cells became O4-positive, and a majority expressed myelin basic protein by 5 day of differentiation, which confirmed the identity of isolated mouse NG2+ cells as OPCs. In comparison to rat OPCs, mouse OPCs in B104CM+FGF2 were less motile, and demonstrated lower basal phosphorylation levels of ERK1/2 and cAMP response element-binding protein (CREB) and a higher incidence of apoptosis mediated by the intrinsic pathway. Transient up-regulation of cAMP-CREB signaling partially inhibited apoptosis of mouse OPCs independently of the ERK pathway. This study demonstrates a difference in trophic requirements between mouse and rat OPCs, with an essential role for cAMP signaling to preserve viability of mouse OPCs. © 2009 Wiley-Liss, Inc.
Reductions in expression of growth regulating genes in skeletal muscle with age in wild type and myostatin null mice

Background Genes that decline in expression with age and are thought to coordinate growth cessation have been identified in various organs, but their expression in skeletal muscle is unknown. Therefore, our objective was to determine expression of these genes (Ezh2, Gpc3, Mdk, Mest, Mycn, Peg3, and Plagl1) in skeletal muscle from birth to maturity. We hypothesized that expression of these genes would decline with age in skeletal muscle but differ between sexes and between wild type and myostatin null mice.
Effects of Illumination and Prey Contrast on Survival and Growth of Larval Yellow Perch Perca flavescens

Abstract The influence of illumination and prey contrast on survival, growth, and feeding of larval yellow perch fed Artemia sp. nauplii was tested in an experimental upflow culture system. The treatment with high light level and high prey contrast (205 lux, black background) supported the best survival (mean, 44.2%) and growth (mean total length, 8.9 mm; mean wet weight, 5.0 mg) from hatching to age 14 d. Mean survival was 37.2% when light was low and prey contrast high (75 lux, black background). In the remainder of the tests, survival to age 14 d ranged from 0 to 6.9%. Low light and low prey contrast caused a 1–2 d delay in initial feeding. Visibility of the prey resulting from contrast with the surroundings, rather than light level, accounted for most of the variation in the ability of yellow perch larvae to acquire adequate food.
Verbal Short-Term Memory Encoding of Learning Disabled, Deaf, and Normal Readers

The present study investigated the hypothesis that nonstrategic verbal encoding abilities are deficient in learning disabled readers. Normal, deaf, and learning disabled children matched on chronological age, IQ, and sex were randomly assigned to named and unnamed stimulus pretraining conditions and compared on subsequent performance on a probe-type serial memory task. Although overt rehearsal was inhibited, strong primacy effects were found for both the named and the unnamed condition. The named condition was superior to the unnamed condition for both normal and deaf but not for learning disabled children. Results were interpreted to indicate a deficient verbal-visual integrative process in disabled children occurring prior to the application of mnemonic strategies. To what extent is short-term memory of visual stimuli dependent upon verbal processes in learning disabled and normal readers? This basic question has generated extensive research on the mnemonic strategies used by learning disabled and nondisabled children. The results suggest that normal children are superior in serial recall tasks which presumably require rehearsal and other mnemonic processes (e.g., Hagen, Meacham, & Mesibov, 1970; Tarver, Hallahan, Kauffman, & Ball, 1976). However, efforts to fully understand processing of visual materials have been hampered by nonstrategic factors, such as differences in verbal-visual integrative abilities in learning disabled and nondisabled subjects (cf. Vellutino, 1977; Vellutino, Steger, DeSetto, & Phillips, 1975). Swanson (1978) found that pretraining in naming unfamiliar visual stimuli resulted in similar acquisition of names by disabled and normal readers. However, disabled children's subsequent recall performance was inferior to that of normal readers, suggesting that the disabled did not use the previously acquired labels to mediate recall. These results indicate that encoding processes, such as verbal-visual integration, may be important for recall differences in normal and disabled
Little science confronts the data deluge: habitat ecology, embedded sensor networks, and digital libraries

e-Science promises to increase the pace of science via fast, distributed access to computational resources, analytical tools, and digital libraries. "Big science" fields such as physics and astronomy that collaborate around expensive instrumentation have constructed shared digital libraries to manage their data and documents, while "little science" research areas that gather data through hand-crafted fieldwork continue to manage their data locally. As habitat ecology researchers begin to deploy embedded sensor networks, they are confronting an array of challenges in capturing, organizing, and managing large amounts of data. The scientists and their partners in computer science and engineering make use of common datasets but interpret the data differently. Studies of this field in transition offer insights into the role of digital libraries in e-Science, how data practices evolve as science becomes more instrumented, and how scientists, computer scientists, and engineers collaborate around data. Among the lessons learned are that data on the same variables are gathered by multiple means, that data exist in many states and in many places, and that publication practices often drive data collection practices. Data sharing is embraced in principle but little sharing actually occurs, due to interrelated factors such as lack of demand, lack of standards, and concerns about publication, ownership, data quality, and ethics. We explore the implications of these findings for data policy and digital library architecture. Research reported here is affiliated with the Center for Embedded Networked Sensing.
Notes on the Distribution and Ecology of Riccia rhenana in Georgia

Abstract. The thallose liverwort Riccia rhenana is one of three species in the taxonomically challenging “Riccia fluitans” complex that typically occur as floating aquatics. Taxonomic uncertainty has made it difficult to determine the geographical distributions and ecological affinities of these species. A further complication is that these plants are widespread and common in the aquarium trade, raising the possibility of human introductions. Recently we collected R. rhenana from a highly distinctive habitat: a cold, clear, high-flow spring in the Chattahoochee National Forest in northwest Georgia. Subsequent checking of earlier collections revealed that this species appears to be restricted to these unusual habitats within a small area in the northwestern corner of the state and in the vicinity of Pine Mountain in westcentral Georgia. We urge other collectors in the Southeast to seek additional localities for these plants and to reexamine earlier collections with these geographical and ecological correla...
Fine-scale measurements of sediment roughness and subbottom variability

As part of the Asian Seas International Acoustics Experiment (ASIAEX), this paper describes the results of fine-scale characterization of surficial sediments at a site in the East China Sea using a conductivity probe. This probe is a modified version of a system originally developed for high-frequency acoustic backscatter applications [see Tang et al., "Fine-scale volume heterogeneity measurements in sand" IEEE J. Oceanic Eng., vol. 27, pp. 546-560, 2002, and Briggs et al., "Characterization of interface roughness of rippled sand off Fort Walton Beach, Florida," IEEE J. Oceanic Eng., vol. 27, pp. 505-514, 2002]. The new system has a single conductivity sensor that can move in both vertical and horizontal directions with controlled steps while taking data, thus resulting in a two-dimensional (2-D) grid on which medium conductivity is measured. Because sediment conductivity is much smaller than that of the overlaying seawater, bottom roughness is determined by selecting the grid points at which conductivity has a sudden drop along each vertical profile. Subbottom density variations are obtained by converting conductivity data to density using Archie's law and core density data. The spatial resolution of the measurements is designed to obtain environmental data suitable for modeling acoustic backscatter in the midfrequency (3-4 kHz) range. The results of this paper include the spectrum of sediment interface roughness and subbottom density gradient profiles. Error analysis is conducted to provide bounds on the results. It is found that bottom roughness is dominated by small features caused by bottom-dwelling organisms. A model is developed to simulate the random distributions of these bottom features. The model employs a superposition of discrete features, which results in a power spectrum that is consistent with the measured power spectrum. Potentially, this kind of model can provide a remote sensing means to estimate bottom biological populations through measuring sound backscatter from the bottom. Although the subbottom heterogeneity spectrum is not obtained at the present time because of measurement errors, it is found that sediment density variance is less than 0.5%, implying that bottom backscatter may be caused primarily by bottom roughness.
Filling constraints for spin-orbit coupled insulators in symmorphic and nonsymmorphic crystals

We determine conditions on the filling of electrons in a crystalline lattice to obtain the equivalent of a band insulator--a gapped insulator with neither symmetry breaking nor fractionalized excitations. We allow for strong interactions, which precludes a free particle description. Previous approaches that extend the Lieb-Schultz-Mattis argument invoked spin conservation in an essential way and cannot be applied to the physically interesting case of spin-orbit coupled systems. Here we introduce two approaches: The first one is an entanglement-based scheme, and the second one studies the system on an appropriate flat "Bieberbach" manifold to obtain the filling conditions for all 230 space groups. These approaches assume only time reversal rather than spin rotation invariance. The results depend crucially on whether the crystal symmetry is symmorphic. Our results clarify when one may infer the existence of an exotic ground state based on the absence of order, and we point out applications to experimentally realized materials. Extensions to new situations involving purely spin models are also mentioned.
Symbiotic Deficiencies Associated with a coxWXYZ Mutant of Bradyrhizobium japonicum

The terminal oxidase complexes encoded by coxMNOP and coxWXYZ were studied by analysis of mutations in each of the two oxidases. Carbon monoxide difference spectra obtained from membranes of coxMNOP mutant bacteroids were like those obtained for the wild type, whereas bacteroid membranes of a coxWXYZ mutant were deficient in CO-reactive cytochrome b. Experiments involving cyanide inhibition of oxidase activity were consistent with the conclusion that the coxX mutant is deficient in a membrane-associated O2-binding component. The viable cell number (bacteria that could be recultured from crushed nodules) was 20 to 29% lower for the coxX mutant than for the wild-type or the CoxN- strain. In three separate greenhouse studies, nodules of a coxX mutant had significantly lower (28 to 34% less) acetylene reduction rates than the wild-type nodules did, and plants inoculated with a double mutant (coxMNOP coxWZYZ) had rates 30% lower than those of wild-type-inoculated plants.
On the performance of COPS-PR and NETCONF in an integrated management environment for DiffServ-enabled networks

Although COPS-PR is a policy management protocol already found in commercial network equipments, the IETF has been also working on the standardization of the NETCONF protocol, which can be seen as a competing solution when employed for QoS management. NETCONF seems to have the potential to become a feasible alternative to the established management protocols (e.g., SNMP), but few is known about its behavior and performance when it is used together with COPSPR. In this paper we present and evaluation of NETCONF and COPS-PR in a management environment for DiffServ-enabled networks. NETCONF to COPS-PR gateways have been developed in order to integrated COPS-PR commercial equipments into networks managed via NETCONF-capable management stations. Through such gateways a set of evaluations have been performed in order to draw the picture of integrated NETCONF and COPS-PR for QoS management. The results presented in this paper can help network operators in selecting adequate management setups, as well as provide guidelines for the improvement of NETCONF.
Kinematics of rotating panels of E-W faults in the San Andreas system: what can we tell from geodesy?

SUMMARY Sets of E- to NE-trending sinistral and/or reverse faults occur within the San Andreas system, and are associated with palaeomagnetic evidence for clockwise vertical-axis rotations. These structures cut across the trend of active dextral faults, posing questions as to how displacement is transferred across them. Geodetic data show that they lie within an overall dextral shear field, but the data are commonly interpreted to indicate little or no slip, nor any significant rate of rotation. We model these structures as rotating by bookshelf slip in a dextral shear field, and show that a combination of sinistral slip and rotation can produce the observed velocity field. This allows prediction of rates of slip, rotation, fault-parallel extension and fault-normal shortening within the panel. We use this method to calculate the kinematics of the central segment of the Garlock Fault, which cuts across the eastern California shear zone at a high angle. We obtain a sinistral slip rate of 6.1 ± 1.1mmyr –1 , comparable to geological evidence, but higher than most previous geodetic estimates, and a rotation rate of 4.0 ± 0.7 ◦ Myr –1 clockwise. The western Transverse Ranges transect a similar shear zone in coastal and offshore California, but at an angle of only 40 ◦ . As a result, the faults, which were sinistral when they were at a higher angle to the shear zone, have been reactivated in a dextral sense at a low rate, and the rate of rotation of the panel has decreased from its long-term rate of ∼5 ◦ to 1.6 ◦ ± 0.2 ◦ Myr –1 clockwise. These results help to resolve some of the apparent discrepancies between geological and geodetic slip-rate estimates, and provide an enhanced understanding of the mechanics of intracontinental transform systems.
Effect of isoflurane on aortic impedance in mice

Isoflurane is the most commonly used anesthetic in mice. We studied the effect of low and high levels of isoflurane (also a potent coronary vasodilator) on aortic impedance in mice. Aortic impedance was determined using pressure and flow velocity signals at baseline (B, pentobarbital anesthesia), low (Isol, 1%), and high (Iso2.5, 2.5%) levels of isoflurane. Significant differences were observed in peak and mean flow velocities, systolic, diastolic, mean and pulse pressures at B and Iso2.5. However in impedance indices only peripheral vascular resistance was significantly different. No changes were observed in the harmonic components that represent pulsatile characteristics of the aorta. Peak left ventricular (LV) pressure was significantly lower at Iso2.5 when compared to B, but ±dP/dt and τ (time constant of LV relaxation) did not change significantly indicating that LV contractility was unaffected. These results show that various levels of isoflurane cause significant changes in vascular hemodynamics and care must be taken to minimize these differences when using isoflurane as an anesthesia.
Digit ratio links prenatal hormone exposure with adult lung function

1measured the lung function of South Korean males and females who were hospitalized for an unrelated surgery. Information about smoking habits was collected and digit ratios were measured. They found a positive correlation between digit ratio and lung function, and secondarily, that the association was more robust in males than in females, evidenced by the fact that correlations between parameters of lung function and digit ratio persisted only for males when multivariate analyses were performed. Additionally, the relationship between digit ratio and lung function disappeared in smokers, indicative of the relatively greater influence of smoking on lung function. The authors concluded that low digit ratios predict poor lung function. To further evaluate the findings, it is helpful to place the results in context with other digit ratio studies. Although digit ratio is regarded as a sexually dimorphic trait, differences between the sexes are small and ranges are overlapping. In virtually every report of significant sex differences, male digit ratio is lower than female digit ratio (more testosterone produces lower digit ratio). However, the present study found male values (0.955 ± 0.035) to be higher than female values (0.936 ± 0.030); the reason for the low female ratios is unclear. Race and ethnicity are also known to influence digit ratios. In one study comparing ethnic differences in children, a different Oriental (Han) population showed sex differences in digit ratio in the expected direction (males lower than females) with males averaging
Magneto-Optic Imaging for aircraft skins inspection: A probability of detection study of simulated and experimental image data

The increasing fleet of aging aircrafts has resulted in an increasing demand for cost effective nondestructive evaluation (NDE) techniques that are accurate, reliable and easy to use. Magneto-Optic Imaging (MOI) is such a technique, which has gained wide acceptance for detection of both surface and subsurface defects in multi-layer aircraft structures. The main advantage of MOI is rapid inspection and ease of interpreting image data in contrast to complex impedance signals from conventional eddy current instruments. One missing piece of the puzzle for advanced MOI systems is how to quantitatively analyze the MO images and understand the detectability limits when image data are acquired under varying operational conditions. This paper presents a probability of detection (POD) study that is conducted using both simulation model-predicted and experimental MO image data. Simulated panels from 3-D FEM model and experimental panels with machined defects are used to generate data for data interpretation by human inspectors or automated systems and subsequently for POD studies. The POD curves demonstrate the merits in optimizing inspection parameters that maximized the performance of current MOI systems. Parameters quantifying the detectability of MO image data using skewness functions are also presented and discussed.
Gamma-ray self attenuation calculations in neutron activation ananlysis: A problem overlooked

Neutron activation analysis has for many years been considered to be a method that relatively is free from matrix interference. While this may be true for the majority of samples such as liquid, biological, air filters and geological aluminum-silicate specimens, there are many other types of samples that contains high Z materials in relatively high abundance that do attenuate low and medium energy gamma-rays. Samples such as heavy metal contaminated soils, ore concentrates and meteorites are prime examples. One can minimize the gamma-ray attenuation phenomena by using small masses of sample. This is not possible when using field environmental samples that are more than often not homogenous, and more sample mass is needed. Using a program called SELFABS, we have developed a very careful evaluation of the self-attenuation factors for a several of low and high Z reference materials. Special attention was given to the effect of the sample mass. Our conclusions indicate that while a great effort is given to various QA/QC procedures little literature information is ever published on the need or use for the calculation of these self-attenuation factors.
Ergodic capacity and average rate-guaranteed scheduling for wireless multiuser OFDM systems

The challenging task of scheduling multi-user orthogonal frequency-division multiplexed transmissions amounts to jointly optimum allocation of subcarriers, rate and power resources. The optimization problem for deterministic channels reduces to an integer program known to be exponentially complex. Interestingly, the present paper shows that almost surely optimal allocation is possible at low complexity in the wireless setup, provided that the random fading channel has continuous distribution function. Specifically, it is established that the ergodic capacity achieving allocation follows a greedy water-filling scheme with linear complexity in the number of users and subcarriers. The result extends to accommodate fairness through general utility functions and constraints on the minimum average user rates. When the channel distribution is known, the optimal on-line scheme relies on low-complexity provably convergent subgradient iterations to obtain pertinent dual variables off line. To accommodate channel uncertainties, stochastic subgradient iterations provide dual variables on line with guaranteed convergence to their off-line counterparts.
Seismic geomorphology and tectonostratigraphic fill of half grabens, West Natuna Basin, Indonesia

Synrift stratigraphy of the Cenozoic grabens in the West Natuna Basin (WNB) is commonly poorly constrained because few deep wells exist. Stratal slices were produced from high-quality Gabus and Belanak three-dimensional (3-D) seismic surveys to image synrift depositional architectures. Using 3-D seismic geomorphology, we identified five facies that were used to construct a detailed seismic stratigraphic interpretation. The interpreted synrift stratigraphy of the WNB shows a strong tectonic control. From this type of analysis, potential hydrocarbon system elements can be identified and mapped. Thus, in petroleum exploration situations in which few well data exist, 3-D seismic geomorphology can be used to provide key stratigraphic insights.
A microeconomic model for simultaneous gate sizing and voltage scaling for power optimization

We investigate the problem of dynamic power optimization through gate sizing and voltage scaling under a given delay constraint. Several algorithms have been proposed in the literature to handle gate sizing and voltage scaling independently or together with the goal of satisfying certain power budget constraints without affecting the timing constraints. Decentralized algorithms have been proposed in the literature for distributing a divisible resource among the components of the system. We formulate the problems as economic models that attempt to distribute the delay among the gates of the circuit such that the dynamic power of the circuit is optimized. Since, optimizing all the gates in the circuit at the same time can be computationally intensive, the gates in a given path are handled together. The circuits are represented as economic models and mathematical formulations are developed which are further transformed as game theoretic models for which Nash equilibrium based solutions are investigated. Thus, the main contribution of this work is the application of microeconomic models and game theory for these VLSI CAD problems. Models are developed for the gate sizing, voltage scaling and simultaneous gate sizing and voltage scaling problems. The algorithms are iterative, fast, simple and can lead to rapid convergence. Competition among the gates can provide the best overall optimization. In the proposed algorithms, the gates compete against each other to optimize their power consumption and hence that of the entire circuit. The proposed solutions yield better power optimization than other methods as shown in the experimental results for MCNC '91 benchmark circuits.
Concerning KAr dating of a basalt flow from the Tahoe-Tioga interglaciation, Sawmill Canyon, southeastern Sierra Nevada, California

Abstract New KAr ages for a basalt flow interbedded with Tahoe and Tioga tills in Sawmill Canyon, southeastern Sierra Nevada, slightly refine previously published ages for the flow and provide an estimate of 53,000 ± 44,000 yr for the Tahoe-Tioga interglaciation.
Maximization of steady‐state Bacterial production in a chemostat with pH and substrate control

This analytical study deals with the steady-state behavior and control of microbial growth in continuous cultures. A second order Haldane-Monod model of continuous cultures is used as a basis for study of the effects of the adjustment of pH by the addition of acidic (or basic) materials. The treatment of a hydrogen ion concentration, in addition to substrate and microbial concentrations as state variables, results in a third order system of equations describing the process. The analysis of the system in equilibrium yields several admissible steady states, that is, steady states which satisfy all constraints. An optimal control problem is formulated and subsequently solved to maximize steady-state microbial production.
Incidence of intracranial hemorrhage in patients with atrial fibrillation who are prone to fall.

PURPOSE: Patients at high risk for falls are presumed to be at increased risk for intracranial hemorrhage, and high risk for falls is cited as a contraindication to antithrombotic therapy. Data substantiating this concern are lacking. METHODS: Quality improvement organizations identified 1245 Medicare beneficiaries who were documented in the medical record to be at high risk of falls and 18 261 other patients with atrial fibrillation. The patients were elderly (mean 80 years), and 48% were prescribed warfarin at hospital discharge. The primary endpoint was subsequent hospitalization for an intracranial hemorrhage, based on ICD-9 codes. RESULTS: Rates (95% confidence interval [CI]) of intracranial hemorrhage per 100 patient-years were 2.8 (1.9‐4.1) in patients at high risk for falls and 1.1 (1.0‐1.3) in other patients. Rates (95% CI) of traumatic intracranial hemorrhage were 2.0 (1.3‐3.1) in patients at high risk for falls and 0.34 (0.27‐0.45) in other patients. Hazard ratios (95% CI) of other independent risk factors for intracranial hemorrhage were 1.4 (1.0‐3.1) for neuropsychiatric disease, 2.1 (1.6‐2.7) for prior stroke, and 1.9 (1.4‐2.4) for prior major bleeding. Warfarin prescription was associated with intracranial hemorrhage mortality but not with intracranial hemorrhage occurrence. Ischemic stroke rates per 100 patient-years were 13.7 in patients at high risk for falls and 6.9 in other patients. Warfarin prescription in patients prone to fall who had atrial fibrillation and multiple additional stroke risk factors appeared to protect against a composite endpoint of stroke, intracranial hemorrhage, myocardial infarction, and death. CONCLUSION: Patients at high risk for falls with atrial fibrillation are at substantially increased risk of intracranial hemorrhage, especially traumatic intracranial hemorrhage. However, because of their high stroke rate, they appear to benefit from anticoagulant therapy if they have multiple stroke risk factors.
Energy-efficient data movement with sparse transition encoding

Data movement over long on-chip interconnects is a major contributor to system energy. This paper presents novel signaling and encoding techniques that toget her improve the energy efficiency of data communication between the processor cores and the last level cache. The proposed techniques make the interconnect energy proportional to the number of ones in the transferred data block (i.e., the block's hamming weight), regardless of the previous state of the interconnect. The hamming weight of each cache block is kept low through a sparse data encoding approach to minimize interconnect energy. Simulation results show that the proposed communication scheme reduces the overall L2 cache energy by 30% on a set of eleven parallel applications with a 0.5% average performance degradation.
The adult central nervous system: Anatomy and physiology

The human brain consists of three basic subdivisions – the cerebral hemispheres, the brain stem, and the cerebellum. Speech is represented by two main areas – Broca’s area in the inferior frontal lobe (expressive speech) and the Wernicke’s area in the temporoparietal cortex (interpretation of language) (Fig. 1.1). Language localization is found in 96% of population in the left. The basal ganglia are a collection of nuclei deep in the white matter of cerebral cortex and contain the substantia nigra. A decrease in function of the dopaminergic neurons located in the substantia nigra causes Parkinson’s disease. The cerebral hemispheres are connected together medially by the corpus callosum. The limbic areas of the brain include the hypothalamus, amygdala, hippocampus, and limbic cortex. Optic nerve (second) leaves the retina of the eye and travels to the optic chiasm, located just below and in front of the pituitary gland. In the optic chiasm, the optic nerve fibers arising from the nasal half of each retina cross over to the other side; but the nerve fibers originating in the temporal retina do not cross over.
The Effect of Co-Administration of Death Camas (Zigadenus spp.) and Low Larkspur (Delphinium spp.) in Cattle

In many rangeland settings, there is more than one potential poisonous plant. Two poisonous plants that are often found growing simultaneously in the same location in North American rangelands are death camas (Zigadenus spp.) and low larkspur (Delphinium spp.). The objective of this study was to determine if co-administration of death camas would exacerbate the toxicity of low larkspur in cattle. Cattle dosed with 2.0 g of death camas/kg BW showed slight frothing and lethargy, whereas cattle dosed with both death camas and low larkspur showed increased clinical signs of poisoning. Although qualitative differences in clinical signs of intoxication in cattle co-treated with death camas and low larkspur were observed, there were not any significant quantitative differences in heart rate or exercise-induced muscle fatigue. Co-treatment with death camas and low larkspur did not affect the serum zygacine kinetics, however, there was a difference in the larkspur alkaloid kinetics in the co-exposure group. Overall, the results from this study suggest that co-exposure to death camas and low larkspur is not significantly more toxic to cattle than exposure to the plants individually. The results from this study increase our knowledge and understanding regarding the acute toxicity of death camas and low larkspur in cattle.
On architectural knowledge and form generation: a theoretical framework using knowledge-based system

The relationship between form generation and architectural knowledge has not yet been adequately established in building design. Form generation, addressing issues of stylistic expression and artistic creativity, is often considered exciting and mystical. Architectural knowledge, consisting of data, facts, and procedures, is thought rigid and uninteresting. Nonetheless, It equips architects with the necessary skills to create safe and healthy environments that fulfill their intended function and harmonize with the natural, cultural, and social contexts. Form generation should not be treated as a separate act of invention, but as an integral part of the design process. It is imperative to examine the underlying factors that inform, regulate, and determine the generation of architectural forms. These factors, which influence design decisions and constitute an architectural knowledge base, consist of: (1) authoritative regulations and standards, (2) programmatic requirements, (3) technology and building materials, (4) physical and socio-cultural environments, and (5) form generation strategies. Based on a review the generative capability of shape grammar developed by Stiny and Gips (1978), a theoretical framework that integrates a form generation mechanism into an architectural knowledge-based system is developed. The idea of frame (Minsky, 1975) is used as the elementary structure for architectural knowledge representation. To implement the inference process of the knowledge-based system, the framework adopts a KBS development shell, Teknowledge M4.0, to formulate the knowledge bases in the form of production rules system. The result is a computational framework that links architecture knowledge, i.e. design data, rules, and procedures, to a form generation mechanism. Thanks to the inference engine, this integrated framework produces sufficient and necessary knowledge in support of design decision-making, and facilitates an informed process of form generation. Its functionality is demonstrated by using the tulou, a type of vernacular architecture created by the Hakka Chinese as a case study. By establishing and implementing a design model that bridges form and knowledge, this study makes a contribution to ongoing research towards a comprehensive, rational, and efficient process of architectural design.
Adapting to Personality Over Time: Examining the Effectiveness of Dialogue Policy Progressions in Task-Oriented Interaction

This paper explores dialogue adaptation over repeated interactions within a taskoriented human tutorial dialogue corpus. We hypothesize that over the course of four tutorial dialogue sessions, tutors adapt their strategies based on the personality of the student, and in particular to student introversion or extraversion. We model changes in strategy over time and use them to predict how effectively the tutorial interactions support student learning. The results suggest that students leaning toward introversion learn more effectively with a minimal amount of interruption during task activity, but occasionally require a tutor prompt before voicing uncertainty; on the other hand, students tending toward extraversion benefit significantly from increased interaction, particularly through tutor prompts for reflection on task activity. This line of investigation will inform the development of future user-adaptive dialogue systems.
Forest to Pastura: development or destruction?

The expansion of artifical or planted pastures (repasto) at the expense of both natural forest and cropland has brought major changes to the landscape and economy of Central America in recent years. On the pioneer fronts at the forest margin agriculture is commonly a transitory stage between forest felling and the establishment of permanent pasture. In the past 15 years the area in planted pasture and the total numbers of beef cattle have nearly doubled in several Central American countries while the per capita consumption of beef has actually declined. The "grassland revolution" that is occuring in Central America and Panama has been based almost exclusively on grass species of African origin which have in most cases been introduced into Central America only in this century. Of these jaragua, guinea, pangola, and kikuyu are the most important. The ecologic consequences of the conversion of forest to pasture are little understood. Intensive management practices, including the application of high-cost and scarce fertilizers and carefully-manged rotational grazing, will probably be necessary to sustain the productivity of these lands under conditions of tropical climate.