cssi/SciSciGPT-SciSciNet huggingface dataset:
Failure of Au RF-MEMS switches subjected to dynamic loading

Abstract The dynamic failure of Au RF-MEMS was investigated over a wide range of loading rates by three different experimental setups: a drop weight tower, which induced a maximum peak acceleration of 600g (g: acceleration of gravity), a Hopkinson pressure bar with a maximum peak acceleration of 300,000g, and a pulsed laser loading technique with a maximum peak acceleration of 1.8 × 108g. In the drop weight tower the total load pulse duration was in the milliseconds range – much longer than the 28 μs resonant period of the devices – and no failure of any kind occurred in the RF-MEMS devices or their substrate. At 90,000g (generated in the Hopkinson bar) no damage in either the substrate or the devices was observed. However, at 200,000g, which corresponds to a loading duration of a few microseconds, i.e., comparable to the device resonant period, 10% of the switches failed although postmortem imaging showed no damage to the substrate. Damage increased after this acceleration and at 300,000g 20% of the switches failed, but, in addition, significant failure in the quartz substrate was recorded. Lastly, the pulsed laser loading technique, which has a loading pulse duration of a few tens of nanoseconds, was applied to accelerate the Au switches to 1.8 × 108g, and the probability of failure at this loading ranged from 50% to 80%. At even larger accelerations, 109g, the probability of failure was 100%. The results of this study establish the severity of dynamic failure in MEMS, despite their small mass, and its dependence on the level of acceleration which spanned about 7 orders of magnitude.
Rhesus monkeys lack a consistent peak-end effect

In humans, the order of receiving sequential rewards can significantly influence the overall subjective utility of an outcome. For example, people subjectively rate receiving a large reward by itself significantly higher than receiving the same large reward followed by a smaller one (Do, Rupert, & Wolford, 2008). This result is called the peak-end effect. A comparative analysis of order effects can help determine the generality of such effects across primates, and we therefore examined the influence of reward-quality order on decision making in three rhesus macaque monkeys (Macaca mulatta). When given the choice between a high–low reward sequence and a low–high sequence, all three monkeys preferred receiving the high-value reward first. Follow-up experiments showed that for two of the three monkeys their choices depended specifically on reward-quality order and could not be accounted for by delay discounting. These results provide evidence for the influence of outcome order on decision making in rhesus mo...
Noise Enhanced Detection as a Special Case of Randomization

It is shown in this letter that the addition of noise to data, resulting in noise enhanced detection, is equivalent to using a randomized decision rule. Since the theory of randomized decision-making is well developed, this link can be exploited to better understand the advantages, disadvantages, and general properties of noise enhanced detection. As an example, we show how some recent results can be interpreted within this more general framework.
Combined effects of deformation (strain and strain state), grain size, and carbon content on carbide precipitation and corrosion sensitization in 304 stainless steel☆

Abstract In this investigation we have examined the combined effects of temperature, aging time, carbon content, grain size, strain, and strain state (uniaxial versus rolling deformation) on sensitization development in 304 stainless steel. In general, increasing the carbon content, strain, and strain state (uniaxial → rolling) decreases the sensitization time. Reducing the grain size also accelerates the rate of sensitization development. In addition, for sufficiently small grain sizes, even with superimposed straining, the grain boundaries become dominant in Cr diffusion kinetics.
Transoral robot-assisted excision of a lingual thyroid gland

Lingual thyroid is a rare condition in which ectopic thyroid tissue is present in the base of tongue. We present a case of a 46-year-old patient with a symptomatic lingual thyroid that was successfully removed with minimal morbidity using transoral robotic surgery. The traditional treatment algorithm for lingual thyroid is reviewed. The advantages of using transoral robotic surgery to remove lingual thyroid tissue are described along with the reasons why the addition of this technique should shift treatment of lingual thyroid towards more frequent use of surgical ablation. This report is, to our knowledge, the first describing the use of transoral robotic surgery for treating lingual thyroid.
Trait fitness is not a propensity, but fitness variation is

The propensity interpretation of fitness draws on the propensity interpretation of probability, but advocates of the former have not attended sufficiently to problems with the latter. The causal power of C to bring about E is not well-represented by the conditional probability Pr(E|C). Since the viability fitness of trait T is the conditional probability Pr(organism O survives to adulthood|O has T), the viability fitness of the trait does not represent the degree to which having the trait causally promotes surviving. The same point holds for fertility fitness. This failure of trait fitness to capture causal role can also be seen in the fact that coextensive traits must have the same fitness values even if one of them promotes survival and the other is neutral or deleterious. Although the fitness of a trait does not represent the trait’s causal power to promote survival and reproduction, variation in fitness in a population causally promotes change in trait frequencies; in this sense, fitness variation is a population-level propensity.
Assessing the impact of the acid deposition control program

Abstract A goal of the acidic deposition control program in the United States has been to link emissions control policies, such as those mandated under Title IV of the US Clean Air Act Amendments (CAAA) of 1990, to improvements in air and water quality. Recently, several researchers have reported trends in the time series of pollutant data in an effort to evaluate the effectiveness of the CAAA in reducing the acidic deposition problem. It is well known that pollutant concentrations are highly influenced by meteorological and climatic variations. Also, spatial and temporal inhomogeneities in time series of pollutant concentrations, induced by differences in the data collection, reduction, and reporting practices, can significantly affect the trend estimates. We present a method to discern breaks or discontinuities in the time series of pollutants stemming from emission reductions in the presence of meteorological and climatological variability. Using data from a few sites, this paper illustrates that linear trend estimates of concentrations of SO2, aerosol SO42−, and precipitation-weighted SO42− and NO3− can be biased because of such complex features embedded in pollutant time series.
Interaction between cell sodium and the amiloride-sensitive sodium entry step in rabbit colon.

Ouabain abolishes the short-circuit current (Isc) and decreases the transepithelial conductance (Gt) of rabbit colon. In contrast, amphotericin B elicits a maximumIsc and markedly increasesGt. However, inboth instances the amiloride-sensitive Na entry step is completely blocked, presumably due to an increase in cell Na. Conversely, when Na-depleted tissues are suddenly exposed to 140mm Na, the amiloride-sensitiveIsc and the amiloride-sensitive component ofGt(aGNa) increase abruptly to their maximum values and the decline to steady-state plateaus with a half time of ∼ 6 min; throughout the decline (Isc/aGNa)=ENa is constant at a value of 95 mV. In the presence of amphotericin B, theIsc abruptly rises to the same maximum but does not decline. These findings indicate that in the presence of 140mm Na the conductance of the amiloride-sensitive Na entry step can vary from a maximum value of approximately 1.6 mmhos/cm2 when cell Na is depleted, to zero when cell Na is abnormally elevated (e.g., in the presence of ouabain or amphotericin B). Our findings are consistent with a system in which the pathway responsible for transcellular Na transport parallels another cellular compartment with which it communicates. The Na capacity of the active transport pathway appears to be very small so that this compartment fills rapidly after exposure of Na-depleted cells to 140mm Na, and active transepithelial Na transport is initiated and reaches steady-state levels quickly. The Na capacity of the second compartment is much larger; the Na content of this compartment appears to be responsible for the negative feedback effect on the permeability of the amiloride-sensitive entry step.
Computing the volume is difficult

For every polynomial time algorithm which gives an upper bound $$\overline {vol}$$ (K) and a lower boundvol(K) for the volume of a convex setK?Rd, the ratio $$\overline {vol}$$ (K)/vol(K) is at least (cd/logd)d for some convex setK?Rd.
Biotechnology and polymer chemistry: a growing relationship

DuPont is using biotechnology to make chemical compounds and materials, especially polymers and polymer intermediates - demonstrating that biotechnology can lead to more effective and productive manufacturing processes for traditional chemical businesses as well as pharmaceuticals, agricultural products, and new products for improved nutrition and health.
Economic aspects of fisheries management with 200 mile resource zones: The Northwest Atlantic area

The purpose of this paper will be to review the progress and preliminary results of a NSF/RANN funded study on management in resource zones. The main parts of the study are as follows: (1) Scope of Problem. A substantive analysis of the scope of the management problems involved in 200 mile fishing zones. (2) History of Fishing and Geographical Effects of Zone. A brief history of the biological and economic aspects of exploitation in the study area and a simple geographical analysis of how a 200 mile zone will redistribute management potential. (3) National Management Problems. An analysis of possible regulatory procedures open to the U. S. for managing stocks that will be under its exclusive control. Variables under study will be efficiency of harvest, total and regional employment effects, potential for license revenues, the combination of national and foreign fishing power used, including the potential and desirability of a 100% American fleet, balance of payment effects, etc.
Modal moment index for damage detection in beam structures

Health monitoring and damage detection in structures such as airframes are crucial to their safety and performance. Damage-induced changes in natural frequencies, damping ratios and mode shapes can be detected using experimental modal analysis (EMA), which has recently enjoyed intense research for application in structural health monitoring. A main theme of the current research has been to formulate a parameter, calculated using the measured changes in eigenparameters, which exhibits a significant “jump” at the damage location and whose value is a direct measure of the severity of the damage. A damage-sensitive parameter thus serves to localize the damage and to assess its severity, and it should likewise minimize the likelihood of false indications or of missing damage. Here, using finite element analysis of the damaged cantilevered beam, we study several existing parameters and introduce a new parameter called the Modal Moment Index (MMI). MMI is shown to jump sharply at the damage site and to have a direct relationship to the damage level.
Analysis of the Role of the Mitogen-Activated Protein Kinase in Mediating Cyclic-Adenosine 3′,5′-Monophosphate Effects on Prolactin Promoter Activity

The mechanisms mediating cAMP effects to stimulate transcription of the PRL gene have been examined. Treatments that elevate intracellular cAMP concentrations were found to stimulate the mitogen-activated protein kinase (MAPK) in GH3 cells. Elevated cAMP was also found to stimulate activation of the GTP-binding protein, Rap1. Rap1GAP1 reduced cAMP-induced phosphorylation of MAPK, offering evidence that Rap1 may play a role in mediating activation of MAPK. Treatment of GH3 cells with PD98059, an inhibitor of the MAPK pathway, reduced the ability of forskolin to activate a PRL reporter gene, providing evidence that MAPK contributes to cAMP-mediated effects on the PRL promoter. As previous studies have implicated Ets factor binding sites within the PRL promoter in mediating responses to MAPK, we expected that the Ets sites would also play a role in cAMP responsiveness. Surprisingly, mutation of all of the consensus Ets factor binding sites in the proximal PRL promoter greatly reduced responsiveness to epider...
Real-time prediction of power system frequency in FNET: A state space approach

This paper proposes a novel approach to predict power frequency by applying a state-space model to describe the time-varying nature of power systems. It introduces the Expectation maximization (EM) and prediction error minimization (PEM) algorithms to dynamically estimate the parameters of the model. In this paper, we discuss how the proposed models can be used to ensure the efficiency and reliability of power systems in Frequency Monitoring Network (FNET), if serious frequency fluctuation or measurement failure occur at some nodes; this is achieved without requiring the exact model of complex power systems. Our approach leads to an easy online implementation with high precision and short response time that are key to effective frequency control. We randomly pick a set of frequency data for one power station in FNET and use it to estimate and predict the power frequency based on past measurements. Several computer simulations are provided to evaluate the method. Numerical results showed that the proposed technique could achieve good performance regarding the frequency monitoring with very limited measurement input information.
Biosynthetic methods for incorporating positron‐emitting radionuclides into compounds of biomedical interest

The progress that has been made in incorporating the short-lived, positron-emitting isotopes N-13 and C-11, into biologically active compounds by biosynthetic means is reviewed. These methods include the use of whole cells or plant leaves to carry out a sequence of metabolic reactions, such as nitrogen fixation or photosynthesis, and the use of purified enzymes to catalyze specific chemical reactions, to form the labeled compounds.
Heidegger's concept of presence

The central question in Heidegger's philosophy, early and late, is that concerning the meaning of being. Recently, some have suggested that Heidegger himself interprets being to mean presence (Anwesen, Anwesenheit, Praesenz), citing as evidence lectures dating from the 1920s to the 1960s. I argue, on the contrary, that Heidegger regards the equation between being and presence as the hallmark of metaphysical thinking, and that it only ever appears in his texts as a gloss on the philosophical tradition, not as an expression of his own ontological commitments. In his early work Heidegger seeks to confront and even correct the traditional interpretation of being by challenging its narrow preoccupation with presence and the present. By the 1930s, however, he abandons the idea that there is anything to‐be intrinsically right or wrong about with regard to the meaning of being and turns his attention instead to what he calls ‘appropriation’ (Ereignis) or the truth of being, that is, the essentially ahistorical co...
Adaptation and generalization in acceleration-dependent force fields

Any passive rigid inertial object that we hold in our hand, e.g., a tennis racquet, imposes a field of forces on the arm that depends on limb position, velocity, and acceleration. A fundamental characteristic of this field is that the forces due to acceleration and velocity are linearly separable in the intrinsic coordinates of the limb. In order to learn such dynamics with a collection of basis elements, a control system would generalize correctly and therefore perform optimally if the basis elements that were sensitive to limb velocity were not sensitive to acceleration, and vice versa. However, in the mammalian nervous system proprioceptive sensors like muscle spindles encode a nonlinear combination of all components of limb state, with sensitivity to velocity dominating sensitivity to acceleration. Therefore, limb state in the space of proprioception is not linearly separable despite the fact that this separation is a desirable property of control systems that form models of inertial objects. In building internal models of limb dynamics, does the brain use a representation that is optimal for control of inertial objects, or a representation that is closely tied to how peripheral sensors measure limb state? Here we show that in humans, patterns of generalization of reaching movements in acceleration-dependent fields are strongly inconsistent with basis elements that are optimized for control of inertial objects. Unlike a robot controller that models the dynamics of the natural world and represents velocity and acceleration independently, internal models of dynamics that people learn appear to be rooted in the properties of proprioception, nonlinearly responding to the pattern of muscle activation and representing velocity more strongly than acceleration.
Minichromosome maintenance as a genetic assay for defects in DNA replication.

Minichromosome maintenance (mcm) is an effective genetic assay for mutants defective in DNA replication. Two classes of mcm mutants have been identified using this screen: those that differentially affect the activities of certain autonomously replicating sequences (ARSs) and those that uniformly affect the activities of all ARSs. The ARS-specific MCM genes are essential for the initiation of DNA replication. Among these are members of the MCM2-7 family that encode subunits of the preinitiation complex and MCM10, whose gene product interacts with members of the Mcm2-7 proteins. Among the ARS-nonspecific MCM gene products are chromosome transmission factors. Refinement of this genetic assay as a screening tool and further analysis of existing mcm mutants may reveal new replication initiation proteins.
Pre-clinical Dementia: Does it Exist?

. Identification of syndromes that will progress to dementia carries immense importance for the management of these diseases when therapies are available and for future research into effective early prevention. Evidence supporting the presence of a preclinical phase for dementia has arisen from a range of different areas. Clinical and epidemiological studies have identified both cognitive and neurological abnormalities which predict the future development of dementia. Similarly, various neuroimaging techniques have identified abnormalities in asymptomatic subjects with significant risk for developing Alzheimer's disease and subjects who show mild cognitive deficits. Neuropathological series are hampered by non-representative study populations and poor antemortem data but in studies where informants have been utilised to provide details of subjects' antemortem cognitive function, evidence indicates that the presence of brain pathology is associated with cognitive deficits. This paper reviews the current literature exploring the presence of a pre-clinical phase for dementia, identifies the weaknesses in this research and provides suggestions for future research.
Prediction of corrosion behavior using neural network as a data mining tool

Abstract A supervised neural network (NN) method was used as a data mining tool to predict corrosion behavior of metal alloys. The NN model learned the underlying laws that map the alloy’s composition and environment to the corrosion rate. Existing corrosion data on corrosion allowable as well as corrosion resistive alloys were collected for both DC and AC corrosion experiments. The data mining results allow us to categorize and prioritize certain parameters (i.e. pH, temperature, time of exposure, electrolyte composition, metal composition, etc.) and help us understand the synergetic effects of the parameters and variables on electrochemical potentials and corrosion rates.
Effects of cryogenic thalamic lesions on the somesthetic evoked response in man.

Abstract The effects of cryogenic lesions of certain thalamic nuclei (mainly VL, VPL and VPM) were determined during surgery on the somesthetic evoked response recorded from the cerebral cortex with epidural and scalp electrodes. A total of 102 dyskinesic patients undergoing cryothalamectomy (without premedication) as a means of relieving incapacitating motor symptoms were used for this study. Somesthetic responses were elicited with electrical stimulation of the contralateral median nerve at the wrist at 1, 2, and 3 x sensory threshold. The evoked responses were algebraically summated using conventional computer techniques. Selective lesions of nucleus VL in nineteen cases did not significantly after the evoked responses recorded in the first 125 msec after the stimulus. Lesions of nucleus VL and a portion of VPL which produced transient paresthesias during freezing, did not significantly depress most components of the evoked response in thirteen cases. However, some of the early components were slightly reduced. Massive lesions of VPL encroaching on VPM and possibly CM produced obvious paresthesias of the hand and reduced all components of the evoked response in fifteen cases. It is suggested that the major components of the somesthetic evoked response within 125 msec following stimulation, are primarily mediated through nucleus VP of the thalamus. The contribution of CM, if any, to the passage of some of the later components is uncertain. In some patients discrepancies between the amplitude of the somesthetic evoked potential and subjective complaints of paresthesias were noted. However, in patients with severe paresthesias involving the contralateral hand and wrist, the somesthetic evoked response to stimulation of the median nerve at the wrist was statistically significantly reduced.
Decrease in glutathione levels of kidney and liver after injection of methionine sulfoximine into rats.

After rats were injected with the convulsant methionine sulfoximine, there was a rapid decrease in the glutathione concentrations of the kidney and liver, but there was no measurable effect (within 5 hours) on brain glutathione. The maximum decreases in the glutathione concentrations of kidney and liver were observed 1 hr after injection and were about 60 and 40%, respectively, of the control levels. The findings suggest that there may be at least two pools of tissue glutathione. Studies in which other amino acids were injected, and earlier in vitro studies, are consistent with the conclusion that methionine sulfoximine affects glutathione synthesis in vivo by inhibiting γ-glutamylcysteine synthetase. Injection of glycylglycine also decreased glutathione levels, an effect probably mediated by γ-glutamyltranspeptidase.
The Nitric Oxide Pathway Is Amplified in Venular vs Arteriolar Cultured Rat Mesenteric Endothelial Cells

To determine if there are differences in nitric oxide activity between pre- and postcapillary microvessels, we studied cultured rat mesenteric arteriolar and venular endothelial cells (RMAEC, RMVEC). We measured expression of endothelial nitric oxide synthase (eNOS), the activity of eNOS, and L-arginine transport in live RMAEC and RMVEC and the L-arginine content of RMAEC and RMVEC lysates. The abundance of eNOS was significantly greater in RMVEC vs RMAEC; this was also true for freshly harvested, pooled microvessels. Baseline NOS activity was higher in RMVEC than in RMAEC. NG-monomethyl-L-arginine (L-NMA; 5 mM) inhibited NOS activity by approximately 70-80% in both RMAEC and RMVEC, indicating that metabolism of l-arginine is largely via NOS. Intracellular L-arginine levels were higher in RMVEC vs RMAEC and well above the eNOS Km in both cell types. L-arginine levels increased with L-NMA in both RMAEC and RMVEC, presumably due to reduced substrate utilization. Since L-arginine transport was not higher in RMVEC vs RMAEC, this may reflect higher intracellular arginine synthesis. A higher intrinsic level of baseline NO production in the postcapillary microvascular endothelium may reflect both the contribution of venular derived NO to control of arteriolar tone and a key role of venular-derived NO in local thrombosis control.
Neuropsychological deficit and learning disability in children with psychiatric disorders: a preliminary report.

The Family Psychology Institrrts of Binghamton, IVY Based on an examination of the papers of Geschwind and Galaburda (1985), who postulated an association between learning disabilities and unilateral delays in cortical development and the research of Porter and Rourke (1985) who identified specific subtypes of "socioemotional" dysfunction among children with learning disabilities, an investigation of the relationship between type of psychopathology (i.e., somatic vs affective vs behavioral dysfunction) and nature of neuropsychological impairment was initiated at our Institute. The purpose of this initial study was to test the hypothesis that children displaying both academic and behavioral, affective or somatic problems would also show evidence of neuropsychological impairment. In our study were examined 42 Caucasian children (34 boys, 8 girls, with an average of 11.7 yr.) who were referred for treatment for academic problems and psychiatric disorders. Each child was evaluated via methods described by Selz and Reitan (1979). By using a criterion of performance of two years below chronologicaI age on a measure of academic achievement, The Peabody Individual Achievement Test, a WISC-R Full Scale IQ 1 90, a scaled score of at least 2 on any of the Reitan tests, and a T score of at least 70 on any of the clinical scales on The Personality Inventory for Children, 4396 of our sample (4 girls and 14 boys) displayed significant neuropsychological deficits, in addition to psychopathology and academic problems. Given the large percentage of children displaying this pattern in our preliminary study, therapists are cautioned to examine thoroughly the neuropsychological functioning of children displaying a combination of academic and psychiatric problems prior to initiating treatment.
Neurotrophins: Keeping track of changing neurotrophic theory

The requirement for neurotrophins in the development of specific neuronal populations is endorsed by transgenic mice lacking neurotrophin receptors, but central nervous regions of the mice are paradoxically unaffected.
Research Note: Scalding Conditions Can Improve the Appearance of Broilers with Scabby-Hip Syndrome

Abstract On processed broiler carcasses, scabs and scratches have become a common cause of downgrading and trimming for commercial processors. Currently, processors may have little or no recourse in reducing the incidence of this problem in the field, but the present report indicates that scalding conditions can improve the appearance of broiler carcasses with scabby hip lesions. Soft-scalding (53.3 C, 120 s) resulted in fewer (P
Ion-Exchange Chromatography of Egg Yolk 3. Species Differences

Abstract NO INFORMATION has been reported on species variations in the fractions of egg yolk obtained by ion-exchange chromatography. Seideman (1966) developed a chromatographic procedure for the fractionation of egg yolk. These results were further published by Seideman et al. (1969). This technique was used to indicate changes in egg yolk caused by pasteurization, centrifugation, freezing and spray drying (see Seideman, 1966; and Seideman and Cotterill, 1969). The purpose of this paper is to show that this same technique can be used to demonstrate differences in turkey, goose and chicken egg yolk. MATERIALS AND METHODS The yolk material was collected and chromatographed as described in a previous paper by Seideman et al. (1969). The chicken eggs were from two populations of birds selected for different traits from the University of Missouri Poultry Farm. The goose egg yolk was from Embdem geese, and the turkey yolk was obtained from Broad Breasted Bronze…
Product-Line Management in Professional Organizations: an Empirical Test of Competing Theoretical Perspectives

Guided by two competing theoretical perspectives, we investigated effects of structure on performance and human resource outcomes of general hospitals. Neither a product-line nor a functional struc...
Matching law choice analyses of ethanol and sucrose consumption in alcohol-preferring (P), nonpreferring (NP), and Sprague-Dawley (SD) rats.

Background: Quantitative models of choice, such as the matching law and behavioral economics, allow for the analysis of alcohol consumption within a choice context. Such models can provide further knowledge of phenotypic differences between selected lines of rats. The current study applied the generalized matching law to the ethanol (EtOH) and sucrose consumption of alcohol-preferring (P), nonpreferring (NP), and Sprague–Dawley (SD) rats. Methods: Male P, NP, and SD rats were trained to consume increasing concentrations of EtOH and water in a limited access, 2-bottle choice procedure. The animals were then given concurrent access to pairs of differing EtOH solutions (2, 4, 6, and 10%, v/v) for 1 h/d. A subset of animals from each rat type was subsequently given access to 8% sucrose for 1 h/d for 5 days, and then concurrent access to pairs of differing sucrose solutions (3, 8, and 15%, w/v) for 1 h/d. The generalized matching law was used to assess the relationship between the relative EtOH and sucrose concentrations and the relative volumes of solutions consumed. Results: The P rats consumed more EtOH and sucrose than the NP and SD rats overall. However, only the P rats consistently consumed disproportionately greater quantities of the higher EtOH concentration than the lower one, indicating overmatching. Additionally, all 3 types of rats displayed overmatching in the sucrose choice experiment. Conclusions: These data provide further evidence of phenotypic differences between the P rats and other types of rats, and suggest that the generalized matching law can be a useful tool for describing rats' EtOH or sucrose consumption in a 2-bottle choice, limited access paradigm.
Force control and degree of motor impairments in chronic stroke.

Objective: This study determined the variability and regularity of force production in impaired upper extremities of chronic stroke survivors. Two hypotheses included: (1) stroke will increase the variability and regularity of force output in comparison to age-matched controls and (2) degree of motor impairments will be positively correlated with the variability and regularity of force output. Methods: Nine chronic stroke and nine age-matched controls performed unimanual isometric wrist and finger extension movements for 20 s to three different target force levels. Force output was indexed by magnitude, accuracy, variability, and regularity. Stroke motor impairment levels were determined by Fugl-Meyer upper extremity assessment. Results: The stroke group demonstrated increased variability and regularity of the force output. Further, motor impairments scaled with increase in variability and regularity of force output. Conclusions: The variability and regularity of force differentiated isometric contractions performed by chronic stroke survivors from age-matched controls. Moreover, in clinical settings an objective assessment of force control on variability and regularity appears to be most meaningful at 25% of MVC. Significance: Increased variability contributes to reduced steadiness in force output. Increased regularity characterizes the adaptability losses in motor capabilities following stroke. This knowledge may facilitate planning and evaluating rehabilitation protocols.
MAXIMIZING MAGNETIC ENERGY STORAGE IN THE SOLAR CORONA

The energy that drives solar eruptive events such as coronal mass ejections (CMEs) almost certainly originates in coronal magnetic fields. Such energy may build up gradually on timescales of days or longer before its sudden release in an eruptive event, and the presence of free magnetic energy capable of rapid release requires nonpotential magnetic fields and associated electric currents. For magnetic energy to power a CME, that energy must be sufficient to open the magnetic field to interplanetary space, to lift the ejecta against solar gravity, and to accelerate the material to speeds of typically several hundred km s{sup -1}. Although CMEs are large-scale structures, many originate from relatively compact active regions on the solar surface-suggesting that magnetic energy storage may be enhanced when it takes place in smaller magnetic structures. This paper builds on our earlier work exploring energy storage in large-scale dipolar and related bipolar magnetic fields. Here we consider two additional cases: quadrupolar fields and concentrated magnetic bipoles intended to simulate active regions. Our models yield stored energies whose excess over that of the corresponding open field state can be greater than 100% of the associated potential field energy; this contrasts with maximum excess energies of onlymore » about 20% for dipolar and symmetric bipolar configurations. As in our previous work, energy storage is enhanced when we surround a nonpotential field with a strong overlying potential field that acts to 'hold down' the nonpotential flux as its magnetic energy increases.« less
Large D/H variations in bacterial lipids reflect central metabolic pathways

Large hydrogen-isotopic (D/H) fractionations between lipids and growth water have been observed in most organisms studied to date. These fractionations are generally attributed to isotope effects in the biosynthesis of lipids, and are frequently assumed to be approximately constant for the purpose of reconstructing climatic variables. Here, we report D/H fractionations between lipids and water in 4 cultured members of the phylum Proteobacteria, and show that they can vary by up to 500‰ in a single organism. The variation cannot be attributed to lipid biosynthesis as there is no significant change in these pathways between cultures, nor can it be attributed to changing substrate D/H ratios. More importantly, lipid/water D/H fractionations vary systematically with metabolism: chemoautotrophic growth (approximately −200 to −400‰), photoautotrophic growth (−150 to −250‰), heterotrophic growth on sugars (0 to −150‰), and heterotrophic growth on TCA-cycle precursors and intermediates (−50 to +200‰) all yield different fractionations. We hypothesize that the D/H ratios of lipids are controlled largely by those of NADPH used for biosynthesis, rather than by isotope effects within the lipid biosynthetic pathway itself. Our results suggest that different central metabolic pathways yield NADPH—and indirectly lipids—with characteristic isotopic compositions. If so, lipid δD values could become an important biogeochemical tool for linking lipids to energy metabolism, and would yield information that is highly complementary to that provided by ^(13)C about pathways of carbon fixation.
Exendin‐4 differentiation of a human pancreatic duct cell line into endocrine cells: Involvement of PDX‐1 and HNF3β transcription factors

Exendin-4 (EX-4), a long acting agonist of GLP-1, induces an endocrine phenotype in Capan-1 cells. Under culture conditions which include serum, approximately 10% of the cells contain insulin and glucagon. When exposed to EX-4 (0.1 nM, up to 5 days), the number of cells containing insulin and glucagon increased to approximately 40%. Western blot analysis detected a progressive increase in protein levels of glucokinase and GLUT2 over 3 days of EX-4 treatment. We explored the sequence of activation of certain transcription factors known to be essential for the beta cell phenotype: PDX-1, Beta2/NeuroD, and hepatocyte nuclear factor 3beta (HNF3beta). Double immunostaining showed that PDX-1 coexisted with insulin and glucagon in EX-4-treated cells. Treatment caused an increase in PDX-1 protein levels by 24 h and induced its nuclear translocation. Beta2/NeuroD protein levels also increased progressively over 24 h. HNF3beta protein level increased twofold as early as 6 h after EX-4 treatment. EMSA results indicated that EX-4 caused a 12-fold increase in HNF3beta binding to PDX-1 promoter area II. Beta2/NeuroD protein levels progressively increased after 24 h treatment. Differentiation to insulin-producing cells was also seen when Capan-1 cells were transfected with pdx-1, with 80% of these cells expressing insulin 3 days after transfection. PDX-1 antisense totally inhibited such conversion. During the differentiation of duct cells to endocrine cells, cAMP levels (EX-4 is a ligand for the GLP-1, G-protein coupled receptor) and MAP kinase activity increased. Our results indicate that EX-4 activates adenylyl cyclase and MAP kinase which, in turn, may lead to activation of transcription factors necessary for an endocrine phenotype.
Reconfigurable Hardware Based Dynamic Data Aggregation in Wireless Sensor Networks

WSNs typically comprise of sensing nodes with limited computational capability and onboard power. The sensed data in a WSN is transmitted from an individual node to a network sink in a multi-hop fashion. Since transmission costs are often several orders of magnitude larger than computational costs, the efficiency of the WSN can be improved by in-network data aggregation techniques. This is, however, problematic because the aggregation to be performed depends on the requirements of the end user / application, and is either unknown at the time of deployment or changes over time. Implementation of fixed aggregation algorithms limits the utility of the network. Software-based implementation of dynamic aggregation techniques offers the required flexibility but has significant processing overhead, especially when the size of the network increases. In this paper, we reduce the processing overhead by implementing dynamic data aggregation using reconfigurable cluster heads (RCHs) based on Field Programmable Gate Arrays (FPGAs). Such an implementation provides the necessary flexibility in data aggregation techniques demanded by real-time applications, while resulting in significant reduction in the query processing time and the overall power consumption in the network. The objective of the paper is to address the performance improvement in Wireless Sensor Networks (WSNs) through the use of reconfigurable cluster heads. Our results demonstrate that different data aggregation algorithms can be dynamically and efficiently implemented on the RCHs in run-time. The proposed approach is a crucial first-step towards the implementation of programmable WSNS.
The development of thin film barriers for encapsulating organic electronics

In this work, we investigate several approaches to the development of encapsulation of organic electronics. A combination of plasma enhanced chemical vapor deposition, atomic layer deposition, and physical vapor deposition are used to make single layer and multilayer thin films and study the impact of structure on effective water vapor transmission rates. It was found that multilayer thin films consisting of organic and inorganic layers as well as inorganic nanolaminates provided the highest performance barrier films with effective water vapor transmission rates less than 5 × 10−5 g/m2/day. Materials such as atomic layer deposition deposited Al 2 O 3 also showed excellent initial performance, but were found to be susceptible to corrosion from water. Combining alumina with other materials was found to improve the long-term performance of the alumina films. Integration of these films into organic solar cell platforms was shown to effectively maintain shelf lifetime performance for more than 7000 h.
Unbalance and harmonic mitigation using battery inverters

Slight unbalance in voltage in a distribution system can result in high unbalance in currents due to induction machine loads. Further, a wide spectrum of harmonic components will be generated in currents due to uncontrolled power electronic loads employing diode-bridge rectifiers. Power quality becomes a critical issue for a microgrid if both induction machine loads and rectifier loads exist. Mitigation of unbalanced and harmonic currents without additional investments is of interest of utility companies. With energy storage systems such as batteries installed for peak shaping and valley filling, power quality improvement through voltage source converter (VSC) based battery inverters is proposed in this paper. This paper develops a Unbalanced Current (UC) and Harmonic Current (HC) controller for battery inverters based on the structure of Proportional-Resonance (PR) controller. Real-Time simulations carried out in RT-LAB demonstrate the grid current can be successfully improved to meet the IEEE standard when the negative sequence component of grid voltage is lower than 4% for the study system in this paper.
Principal Component Analysis of Phenolic Acid Spectra

Phenolic acids are common plant metabolites that exhibit bioactive properties and have applications in functional food and animal feed formulations. The ultraviolet (UV) and infrared (IR) spectra of four closely related phenolic acid structures were evaluated by principal component analysis (PCA) to develop spectral models for their rapid detection. Results demonstrated that UV and IR spectra could discriminate between each of the phenolic acids in overall models. Calculation of model scores and loadings showed that derivative UV spectra accounted for 99% variation with 2 principal components (PC) while derivative IR spectra required 3 PCs. Individual PCA models were developed for ferulic acid and p-coumaric acid using derivative UV spectra for detection and classification by soft independent modeling of class analogy (SIMCA). The application of this spectral technique as a classification model is expected to promote the use of agricultural residues as a source of these phenolic compounds.
Reduced Feedback Schemes Using Random Beamforming in MIMO Broadcast Channels

A random beamforming scheme for the Gaussian MIMO broadcast channel with channel quality feedback is investigated and extended. Considering the case where the n receivers each have N receive antennas, the effects of feeding back various amounts of signal-to-interference-plus-noise ratio (SINR) information are analyzed. Using the results from order statistics of the ratio of a linear combination of exponential random variables, the distribution function of the maximum order statistic of the SINR observed at the receiver is found. The analysis from viewing each antenna as an individual user is extended to allow combining at the receivers, where it is known that the linear MMSE combiner is the optimal linear receiver and the CDF for the SINR after optimal combining is derived. Analytically, using the Delta Method, the asymptotic distribution of the maximum order statistic of the SINR with and without combining is shown to be, in the nomenclature of extreme order statistics, of type 3. The throughput of the feedback schemes are shown to exhibit optimal scaling asymptotically in the number of users. Finally, to further reduce the amount of feedback, a hard threshold is applied to the SINR feedback. The amount of feedback saved by implementing a hard threshold is determined and the effect on the system throughput is analyzed and bounded.
Developmental influences on speech-motor equivalence: some implications for articulatory disordered children

The peak amplitude of EMG activity was measured from the orbicularis oris superior (OOS), orbicularis oris inferior (OOI) and masseter muscles for 3 normal 4-yr.-old children and compared to past data gathered on a group of articulatory disordered children, normal children, and adults. The 4-yr.-olds evidenced greater average peak EMG activity than the other groups, suggesting that speech-sound production becomes more efficient with maturation. Also, levels of variability obtained for the younger children were considerably smaller than for the normal speakers across the three muscles, showing that motor equivalence changes with age whereby the flexibility in the control of articulators increases. The coefficient of variation for the OOI muscle for the disordered children, however, was similar to that for the 4-yr.-olds, while the corresponding data for the other two muscles paralleled those for normal ones. These findings were interpreted as reflecting a delay in the development of speech-motor equivalence that affects certain muscles while sparing others.
Endogenous cardiac stem cells for the treatment of heart failure

Stem cell-based therapies hold promise for regenerating the myocardium after injury. Recent data obtained from phase I clinical trials using endogenous cardiovascular progenitors isolated directly from the heart suggest that cell-based treatment for heart patients using stem cells that reside in the heart provides significant functional benefit and an improvement in patient outcome. Methods to achieve improved engraftment and regeneration may extend this therapeutic benefit. Endogenous cardiovascular progenitors have been tested extensively in small animals to identify cells that improve cardiac function after myocardial infarction. However, the relative lack of large animal models impedes translation into clinical practice. This review will exclusively focus on the latest research pertaining to humans and large animals, including both endogenous and induced sources of cardiovascular progenitors.
Equilibrium dialysis studies of polyamine binding to DNA.

Binding constants and binding site sizes for the interactions of the polyamines spermine (+4), spermidine (+3), and putrecine (+2) with helical DNA have been determined as a function of ionic conditions and temperature by equilibrium dialysis using 14C-labeled polyamines. In addition, competition equilibrium dialysis has been used to determine binding parameters for the divalent cations putrescine and Mg2+ from the competitive effect of these ions on the binding of spermine or spermidine. In all cases, the logarithm of the binding constant (log Kobs) varies linearly with the logarithm of the monovalent salt concentration; the slopes d log Kobs/d log[NaCl] are proportional to the valence of the ligand, and values of the extrapolated binding constants at 1M NaCl obtained from the intercepts are small (of order 1–10M−1). In those cases examined, Kobs is insensitive to temperature; the free energy of binding is predominantly entropic. Consequently, polymines as DNA-binding ligands behave analogously to the oligolysines investigated previously [cf. Record, Lohman & de Haseth (1976) J. Mol. Biol.107, 145–158; Lohman, de Haseth & Record (1980) Biochemistry19, 3522–3530]. The interactions of these oligocations with DNA are predominantly electrostatic and are driven by the release of thermodynamically bound electrolyte ions from the vicinity of the DNA. The extent to which these oligocations are localized at individual phosphate binding sites or delocalized on the DNA molecule is currently not known.
Photopigments and color vision in the nocturnal monkey,Aotus

The owl monkey (Aotus tridrgutus) is the only nocturnal monkey. The photopigments of Aotus and the relationship between these photopigments and visual discrimination were examined through (1) an analysis of the tlicker photometric electroretinogram (ERG), (2) psychophysical tests of visual sensitivity and color vision, and (3) a search for the presence of the photopigment gene necessary for the production of a short-wavelength sensitive (SWS) photopigment. Roth electrophysiological and behavioral measurements indicate that in addition to a rod photopigment the retina of this primate contains only one other photopigment type-a cone pigment having a spectral peak cu 543 nm. Earlier results that suggested these monkeys can make crude color discriminations are interpreted as probably resulting from the joint exploitation of signals from rods and cones. Although Aotus has no functional SWS photopigment, hybridization analysis shows that A&us has a pigment gene that is highly homologous to the human SWS photopigment gene. Aotus trivirgatus Cone photopigments Monkey color vision Monochromacy Photopigment genes Evolution of color vision