cssi/SciSciGPT-SciSciNet huggingface dataset:
Verification of resource controller processes

Shared resources and the processes that control them play a critical role in the functioning of concurrent systems. A shared resource is viewed as an abstract data type consisting of the definition of the resource and the operations on it, with additional synchronization constraints. Here we present a technique for verifying resource controllers using the formalism of temporal logic. Properties of the operations on a given shared resource are first verified. This is followed by the verification of invariant and liveness properties of the controller. The technique is illustrated by its application to resource controller tasks in Ada. As a prerequisite for accomplishing this, we specify the semantics of Ada tasking primitives.
Negotiating Ethical Dilemmas In The Classroom From A Cross-Literary and Multicultural Context

The topic of character and ethics in public schools has been the subject of scrutiny and debate in this decade, especially with politicians and journalists. The context for this debate, however, is rarely nuanced and some of the assertions made about character and ethics by the afore-mentioned groups are highly decontextualized. In other words, there is a need for educators to weigh in on this debate with some insights from their classroom experiences throughout the entire country.
Image Pre-compensation: Balancing Contrast and Ringing

The goal of image pre-compensation is to process an image such that after being convolved with a known kernel, will appear close to the sharp reference image. In a practical setting, the pre-compensated image has significantly higher dynamic range than the latent image. As a result, some form of tone mapping is needed. In this paper, we show how global tone mapping functions affect contrast and ringing in image pre-compensation. In particular, we show that linear tone mapping eliminates ringing but incurs severe contrast loss, while non-linear tone mapping functions such as Gamma curves slightly enhances contrast but introduces ringing. To enable quantitative analysis, we design new metrics to measure the contrast of an image with ringing. Specifically, we set out to find its "equivalent ringing-free" image that matches its intensity histogram and uses its contrast as the measure. We illustrate our approach on projector defocus compensation and visual acuity enhancement. Compared with the state-of-the-art, our approach significantly improves the contrast. We believe our technique is the first to analytically trade-off between contrast and ringing.
Effects of temperature and r.f. power sputtering on electrical and optical properties of SnO2

Abstract Electrical and optical properties of SnO2, which is a photovoltaic material for solar energy conversion to electricity, have been investigated. Semi-conducting SnO2 has been grown by r.f. sputtering.We report the influence of process variables, such as substrate temperature and r.f. power. The film resistivity decreases with increasing temperature, but rises with increasing r.f. power: these can be related to crystallite size and the film orientation respectively. From the optical measurements, we deduce a variation of band-gap energy with substrate temperature. We show that the substrate temperature has a subsequent influence on the electrical and optical properties of this material.
Artin groups, rewriting systems and three-manifolds

Abstract We construct finite complete rewriting systems for two large classes of Artin groups: those of finite type, and those whose defining graphs are based on trees. The constructions in the two cases are quite different; while the construction for Artin groups of finite type uses normal forms introduced through work on complex hyperplane arrangements, the rewriting systems for Artin groups based on trees are constructed via three-manifold topology. This construction naturally leads to the question: Which Artin groups are three-manifold groups? Although we do not have a complete solution, the answer, it seems, is “not many”.
Bulk models of the sheared convective boundary layer : Evaluation through large eddy simulations

Abstract A set of first-order model (FOM) equations, describing the sheared convective boundary layer (CBL) evolution, is derived. The model output is compared with predictions of the zero-order bulk model (ZOM) for the same CBL type. Large eddy simulation (LES) data are employed to test both models. The results show an advantage of the FOM over the ZOM in the prediction of entrainment, but in many CBL cases, the predictions by the two models are fairly close. Despite its relative simplicity, the ZOM is able to quantify the effects of shear production and dissipation in an integral sense—as long as the constants describing the integral dissipation of shear- and buoyancy-produced turbulence kinetic energy (TKE) are prescribed appropriately and the shear is weak enough that the denominator of the ZOM entrainment equation does not approach zero, causing a numerical instability in the solutions. Overall, the FOM better predicts the entrainment rate due to its ability to avoid this instability. Also, the FOM i...
Enthalpy of dissociation of water at 325°C and LogK, ΔH, ΔS, and ΔCp values for the formation of NaOH(aq) from 250 to 325°C

The aqueous reactions H++OH−=H2O at 325°C and Na++OH−= NaOH(aq) at 250–325°C, were studied using a flow calorimeter. Heats of mixing of aqueous NaOH and HCl solutions were measured at 325°C. The enthalpy of water formation (ΔH=95.9 kJ-mol−1, valid at 12.4 MPa and infinite dilution) was obtained at this temperature from the heat of mixing data but differs significantly from that calculated from the Marshall-Franck equation. This calorimetric ΔH at 325°C was used in combination with literaturelog K and ΔH values at lower temperatures to derive equations representinglog K, ΔH, ΔS, and ΔCp for the formation of water from 250 to 325°C. Heats of dilution of aqueous NaOH solutions were measured at 250, 275, 300, and 325°C. Log K, ΔH, and ΔS for the formation of NaOH(aq) were determined at these temperatures from the fits of the calculated and measured heats while ΔCp values were calculated from the variation of ΔH with temperature. No previous experimental results have been reported for the formation of NaOH(aq). The isocoulombic reaction principle is tested using thelog K values obtained in this study. The plot oflog K vs. 1/T for the isocoulombic reaction NaOH(aq) +H+=H2O+Na+ is approximately linear.
Coupling of the left ventricular and arterial system

We investigated the coupling of the left ventricle (LV) and the arterial system in eight conscious dogs, instrumented to measure LV pressure and determine LV volume from three ultrasonically determined dimensions. The LV end-systolic pressure (PES)-volume (VES) relation was determined by caval occlusion. Its slope (EES) was compared to the arterial elastance (EA), determined as PES/stroke volume. At rest, with intact reflexes, EES/EA was 0.9 +/- 0.20. EES/EA was varied over a wide range (0.18-2.59) by the infusion of graded doses of phenylephrine and nitroprusside and dobutamine. Maximum LV SW, at constant inotropic state and end-diastolic volume, occurred when EES/EA = 0.99 +/- 0.15. However, SW was within 20% of its maximum value when EES/EA was between 0.56 and 2.29. As EES/EA decreased below 0.59, SW fell precipitously. The shape of the observed relation of SW to EES/EA was similar to that predicted by the theoretical consideration of linear LV PES-VES and arterial PES-stroke volume relations. We conclude that the LV and arterial system produce maximum SW at constant VED when EES and EA are equal; however, the relation of SW to EES/EA has a broad plateau.
Visual mate-searching behaviour in the evening brown butterfly, Melanitis leda (L.) (Lepidoptera: Nymphalidae)

As in most animals, male butterflies are generally the more proactive sex with respect to seeking out mating opportunities. In most cases, males conduct their search sometime between mid-morning and mid-afternoon, but a few species are active only before dawn or after sunset. These crepuscular species offer a good opportunity to study how males deal with markedly different visual and thermal conditions. Here, I present data from a 5-month behavioural study of male Melanitis leda (Nymphalidae) at a mate-encounter site in tropical Australia. Males of this species defended perching locations along a forest edge in a similar manner to other diurnally active territorial nymphalids. They generally arrived at these sites after sunset and arrived earlier on evenings that darkened earlier. Actively mate-locating males were only seen at the site during a 25−35 min evening period, during which ambient light levels ranged between 50 and 2600 lux. Only 27% of marked territory residents were recorded again at their location of capture, but fidelity in this ‘resighted’ group ranged up to 23 days. A sample of males, captured under ambient temperatures of 24.0−27.2°C, maintained a mean thoracic excess of 8.25 ± 0.73°C, but did not appear to ‘shiver’ in the manner of other crepuscular species. Males courted conspecific females and one mating was observed. This species is an excellent candidate for further research into the evolution of mating tactics in crepuscular butterflies.
Translocation and Transcriptional Arrest during Transcript Elongation by RNA Polymerase II

RNA polymerase II may stop transcription, or arrest, while transcribing certain DNA sequences. The molecular basis for arrest is not well understood, but a connection has been suggested between arrest and a transient failure of the polymerase to translocate along the template. We have investigated this question by monitoring the movement of RNA polymerase II along a number of templates, using exonuclease III protection as our assay. We found that normal transcription is accompanied by essentially coordinate movement of the active site and both the leading and trailing edges of the polymerase. However, as polymerase approaches an arrest site, translocation of the body of the polymerase stops while transcription continues, leading to an arrested complex in which the 3′ end of the transcript is located much closer than normal to the front edge of the polymerase. Surprisingly, mutated arrest sites that no longer block transcription continue to direct the transient failure of polymerase translocation. As transcription proceeds through these sequences, the initially stationary polymerase moves forward 10-15 bases along the template in response to the addition of only 3 bases to the nascent RNA. Mutagenesis studies indicate that the sequences responsible for the transient block to polymerase movement are located downstream of the T-rich motif required for arrest. Our results indicate that blocking translocation is not sufficient to cause arrest.
Enhancement of opiate binding to neural membranes with an ethyl glycolate ester of phosphatidyl serine

In order to elucidate the mechanism by which acidic lipids enhance the stereospecific high-affinity binding of opiates to neural membranes, chemical synthesis and testing of modified lipid derivatives were undertaken. Phosphatidyl serine ethyl glycolate ester was synthesized from phosphatidyl serine (PS) and ethyl diazoacetate and purified by preparative TLC on silica gel. The PS ester enhanced the specific binding of [3H]dihydromorphine to synaptic membranes from rat brain by 26%, while the enhancement with PS was 35% over control without added lipid. In contrast to PS, there was no complex formation between the PS ester and opiates or Ca2+, ruling out these possible mechanisms. It is suggested that acidic lipids enhance opiate binding by a direct interaction with the receptor.
Studies with Thiohexital, an Anesthetic Barbiturate Metabolized with Unusual Rapidity in Man

Thiohexital, a des-methyl-thio analog of methohexital, has been found to be the most rapidly metabolized intravenous barbiturate yet studied in man. It is more highly bound to plasma proteins than are thiopental and methohexital. The uptake by human adipose tissue, studied in vivo by means of serial biopsies, was considerably less than the uptake of thiopental. An analysis which correlates clinical features of the drug with physicochemical and metabolic factors is presented. It appears that a more rational approach to drug design based on these considerations would lead to a superior anesthetic barbiturate.
Molecular origins of acetan solution properties.

Abstract Acetan is a branched acidic heteropolysaccharide secreted by Acetobacter xylinum . X-ray diffraction studies of oriented fibres suggest non-crystalline helices with fivefold symmetry and a pitch of 4.8 nm. Optical rotation and circular dichroism studies are consistent with the retention of the helical structure in solution and a helix-coil transition upon heating and cooling. Aqueous solutions yield high ‘low shear rate’ viscosity and shear-thin upon shearing.
Xenopus laevis P23H rhodopsin transgene causes rod photoreceptor degeneration that is more severe in the ventral retina and is modulated by light.

Rhodopsin transgenes carrying mutations that cause autosomal dominant retinitis pigmentosa in humans have been used to study rod photoreceptor degeneration in various model organisms including Xenopus laevis. To date, the only transgenes shown to cause rod photoreceptor degeneration in Xenopus laevis have been either mammalian rhodopsins or chimeric versions of rhodopsin based mainly on Xenopus laevis rhodopsin sequences but with a mammalian C-terminus. Since the C-terminal sequence of rhodopsin is highly conserved in mammals and divergent in Xenopus laevis, and mammalian and epitope-tagged rhodopsins may have unexpected properties as transgenes, we decided to test whether a Xenopus laevis rhodopsin transgence carrying only the P23H mutation could also cause rod photoreceptor degeneration. Xenopus laevis tadpoles expressing these transgenes indeed had shortened outer segments and, in severely affected animals, the loss of rod photoreceptors but not the loss of cone photoreceptors. RT-PCR analyses showed that less than 10% of mutant transgenic rhodopsin relative to wild-type endogenous rhodopsin mRNA was sufficient to produce severe rod photoreceptor degeneration. As observed in other animal models as well as humans carrying this particular rhodopsin mutation, the rod photoreceptor degeneration was most severe in the ventral retina and was modified by light. Thus, the rod photoreceptor degeneration produced in Xenopus laevis by the P23H mutation in an otherwise untagged Xenopus laevis rhodopsin is generally similar to that seen with mammalian rhodopsins and epitope-tagged versions of Xenopus laevis rhodopsin, though some differences remain to be explained.
Diphenylhydantoin reduces the outward current of the action potential in Aplysia.

Abstract Diphenylhydantoin (DPH) has been shown to prolong the repolarization phase of action potentials in Aplysia and to reduce the spike after hyperpolarization. We voltage-clamped somata of Aplysia giant neurons and measured the action potential currents to determine what alterations might be responsible for the prolonged repolarization and reduced undershoot. DPH did not affect the peak inward current; however, it did reversibly reduce the outward current at concentrations of 38 μM or greater. The data indicate that DPH reduced the voltage sensitive potassium conductance rather than the ‘A’ current or the calcium activated potassium conductance. These changes in outward current would explain the prolonged action potentials and reduced afterhypolarization seen with DPH in Aplysia.
Optical tomography of a realistic neonatal head phantom

We have begun clinical trials of optical tomography of the neonatal brain. To validate this research, we have built and imaged an anatomically realistic, tissue-equivalent neonatal head phantom that is hollow, allowing contrasting objects to be placed inside it. Images were reconstructed by use of two finite-element meshes, one generated from a computed tomography image of the phantom and the other spherical. The phantom was filled with a liquid of the same optical properties as the outer region, and two perturbations were placed inside. These were successfully imaged with good separation between the absorption and scatter coefficients. The phantom was then refilled with a liquid of increased absorption compared with the background to simulate the brain, and the absolute properties of the two regions were found. These were used as a priori information for the complete reconstruction. Both perturbations were visible, superimposed on the increased absorption of the central region. The head-shaped mesh performed slightly better than the spherical mesh, particularly when the absorption of the central region of the phantom was increased.
Therapeutic approaches for sticky situations

Abstract IBC Conference on Integrins: Applying Multidisciplinary Approaches for Targeted Therapies2IBC USA publish documentation of their conferences. For more information, write to them at IBC USA Conferences, 225 Turnpike Road, Southborough, MA 01772–1749, USA, or visit their Web site at http://www.ibcusa.com/conf/integrins. 2 , Cambridge, MA, USA, 29–30 January 1998
Mid-chain branched mono- and dimethyl alkanes in hot spring cyanobacterial mats: A direct biogenic source for branched alkanes in ancient sediments?

Hot spring cyanobacterial mats from Yellowstone National Park, U.S.A. and the Orakei Korako thermal area, New Zealand have been found to contain suites of monomethyl alkanes, compounds frequently reported in cultured and natural populations of cyanobacteria. The complete range of possible structural isomers for mid-chain branching for C17/C18 and C16/C18 alkanes occurs in the two mats, respectively. Several C19 dimethyl and C20 multibranched alkanes were also observed as major hydrocarbons of the Orakei Korako mat. The recognition of series of mid-chain branched alkanes in modern cyanobacterial mats suggests that their occurrence in ancient sediments may reflect direct biogenic contributions, rather than formation by diagenetic processes.
Exploring the margins: A Second Source for Anonymous 7

(1992). Exploring the margins: A Second Source for Anonymous 7. Journal of Musicological Research: Vol. 12, No. 3, pp. 213-243.
Memory Function and the Clinical Differentiation of Dementing Disorders

For the demented patient, relatively accurate bedside diagnosis is feasible by use of a carefully designed neurologic examination coupled with an understanding of the neuroanatomy of memory and related cognitive processes. Further confirmation of the clinical diagnosis by the application of selected laboratory diagnostic procedures can then result in an appropriate plan of treatment. With the promise of continued development of new therapeutic modalities for specific dementing illnesses such as Alzheimer's disease, a parallel improvement in diagnostic precision seems mandatory in order to permit detection of the disease at an earlier stage. A clinical anatomic approach with special emphasis on the understanding and assessment of memory function is suggested as a starting point. It is hoped that the serial examination of a significant number of patients by this method will eventually yield clues to aid in the earlier differential diagnosis of dementia.
Characterization of hydrogels formed from acrylate modified poly(vinyl alcohol) macromers

Abstract Poly(vinyl alcohol) was modified with pendent acrylate groups to form a macromer that was crosslinked via photopolymerization. Polymerization behavior was studied for several initial macromer concentrations using DSC and Near-IR spectroscopy. Under mild photoinitiating conditions (e.g. 0.05 wt% initiator and less than 20 mW/cm2 of 365 nm light), the hydrogels polymerized to 100% conversion in less than 5 min. To characterize the network structure, the hydrogels formed from the acrylated poly(vinyl alcohol) macromer were compared to gels that were chemically crosslinked with glutaraldehyde and gels that were physically crosslinked by semi-crystalline regions introduced through freeze–thaw cycles. The equilibrium swelling ratio and compressive modulus were characterized for all of the resulting PVA hydrogels, and related to the network structure (i.e. M c ) through a modified Flory–Rehner equation and rubber elasticity theory.
Concept Learning as a Function of Type, Identifiability, and Variety of Instructional Instances.

AbstractSubject matter concept attainment by adult Ss was studied by experimentally manipulating instructional instances which were either positive or negative, clear or obscure, or presented in large or small variety. Training and testing instances were composed of case studies communicated via prose descriptions that had been analyzed for relevant and irrelevant attributes. Conceptualization was defined as generalization within and discrimination between classes and was assessed by having 176 undergraduate volunteers classify new positive and negative case studies after instruction comprised of a definition and selected instances. Two three-way ANOVAs followed by tests of simple effects revealed that instance type, identifiability, and variety have differential effects on generalization and discrimination.
Development of 1.25 THz SIS mixer for Herschel Space Observatory

ABSTRACT We summarize the development and the delivery of two SIS mixers for the 1.1-1.25 THz band of the heterodyne spectrometer of Herschel Observatory (HSO). The quasi-op tical SIS mixer has two Nb/Al N/NbTiN junctions with the area of 0.25 um 2 . The Josephson critical current density in the junction is 30-50 kA/cm . The tuning circuit integrated with SIS junc tion has the base electrode of Nb and a gold wire layer. With the new SIS mixers the test receiver maximum Y factor is 1.41. The minimum receiver uncorrected DSB noise temperature is 450 K. The SIS receiver noise corrected for the loss in the optics is 350-450 K across the 1100-1250 GHz band. The receiver has a uniform sensitivity in the full IF range of 4-8 GHz. The sub-micron sized SIS junction shape is optimized to ease the suppression of the Josephson current, and the receiver operation is stable. The measured mixer beam pattern is symmetrical and, in a good agreement with the requirements, has the f/d =4.25 at the central frequency of the operation band. The minimum DSB SIS receiver noise is close to 6 hv/k, the lowest value achieved thus far in the THz frequencies range. Keywords: SIS mixer, THz frequency, far infrared, low noise, Herschel space observatory, radio astronomy.
THE IDEOLOGY OF BINARY OPPOSITION: SUBJECT/OBJECT DUALITY AND ANTHROPOLOGY

The thrust of this paper can be described as an attempt to critically address the fundamen? tal historical oppositon in anthropology ? the anthropologist and his* context. The history of mainstream anthropology has to a great ex? tent consisted of the struggle to legitimate the supposed natural opposition between subject and object, an opposition steeped in Cartesian duality and one which I propose to be a false epistemological construct of an ideological nature which mirrors particular patterns of production and reproduction on a societal level. To use the phraseology of Anthony Wilden, I want to suggest that the way out of this false duality is situated in the radical "deconstruc tion of the dominant scientific discourse" [ 1 ] as one aspect of the parallel deconstruction of our exploitive and alienating social context itself. Such is the task of a critical anthropol? ogy. The history of anthropology has been domi? nated by various attempts to create a science of "methods" with which, like the telescope of the astronomer, reality may be discovered
The Identity Question for African Youth Developing the New While Maintaining the Old

The identity question is one that African immigrants have to contend with in the acculturation into the American society. The confluence of different cultures detracts continuity of the ethnic iden...
Constraint partitioning in penalty formulations for solving temporal planning problems

In this paper, we study the partitioning of constraints in temporal planning problems formulated as mixed-integer nonlinear programming (MINLP) problems. Constraint partitioning is attractive because it leads to much easier subproblems, where each is a significant relaxation of the original problem. Moreover, each subproblem is very similar to the original problem and can be solved by any existing solver with little or no modification. Constraint partitioning, however, introduces global constraints that may be violated when subproblems are evaluated independently. To reduce the overhead in resolving such global constraints, we develop in this paper new conditions and algorithms for limiting the search space to be backtracked in each subproblem. Using a penalty formulation of a MINLP where the constraint functions of the MINLP are transformed into non-negative functions, we present a necessary and sufficient extended saddle-point condition (ESPC) for constrained local minimization. When the penalties are larger than some thresholds, our theory shows a one-to-one correspondence between a constrained local minimum of the MINLP and an extended saddle point of the penalty function. Hence, one way to find a constrained local minimum is to increase gradually the penalties of those violated constraints and to look for a local minimum of the penalty function using any existing algorithm until a solution to the constrained model is found. Next, we extend the ESPC to constraint-partitioned MINLPs and propose a partition-and-resolve strategy for resolving violated global constraints across subproblems. Using the discrete-space ASPEN and the mixed-space MIPS planners to solve subproblems, we show significant improvements on some planning benchmarks, both in terms of the quality of the plans generated and the execution times to find them.
A behavioural output enhancing effect of imipramine in pigeons

Abstract Imipramine causes an increase in behavioural output of pigeons working on a multiple schedule of positive reinforcement. In the same circumstances, desmethylimipramine and methamphetamine, but not chlorpromazine, generally had similar effects.
Strategic Plan for Coordinating Rural Intelligent Transportation System (ITS) Transit Development in the Great Smoky Mountains National Park

The Great Smoky Mountains National Park, located along the border between North Carolina and Tennessee, is the most visited national park in the United States. This rugged, mountainous area presents many transportation challenges. The immense popularity of the Smokies and the fact that the primary mode of transportation within the park is the personal vehicle have resulted in congestion, damage to the environment, impacts on safety, and a degraded visitor experience. Access to some of the Smokies historical, cultural, and recreational attractions via a mass transit system could alleviate many of the transportation issues. Although quite a few organizations are proponents of a mass transit system for the Smokies, there is a lack of coordination among all parties. In addition, many local residents are not completely comfortable with the idea of transit in the Smokies. This document provides a brief overview of the current transportation needs and limitations in the Great Smoky Mountains National Park, identifies agencies and groups with particular interests in the Smokies, and offers insights into the benefits of using Intelligent Transportation Systems (ITS) technologies in the Smokies. Recommendations for the use of rural ITS transit to solve two major transportation issues are presented.
Understanding the Factors Affecting Degree Completion of Doctoral Women in the Science and Engineering Fields.

This chapter examines the retention and degree completion of doctoral women in the science fields. The research shows that the lower degree completion rate for women may be a result of fewer opportunities for research assistantships.
Fractured solutions in the calculus of variations

We derive necessary conditions and sufficient conditions for a strong minimum of a variational problem over a class of functions which allow for a finite number of fractures (simple discontinuities) in the dependent variable. Our analysis is applicable, with some modification, to variational problems which arise in the optimization of hydrodynamically lubricated bearings.
Structural contributions to the pressure-tuned charge-density-wave to superconductor transition in ZrTe 3 : Raman scattering studies

Superconductivity evolves as functions of pressure or doping from charge-ordered phases in a variety of strongly correlated systems, suggesting that there may be universal characteristics associated with the competition between superconductivity and charge order in these materials. We present an inelastic light (Raman) scattering study of the structural changes that precede the pressure-tuned charge-density-wave (CDW) to superconductor transition in one such system, ${\mathrm{ZrTe}}_{3}$. In certain phonon bands, we observe dramatic linewidth reductions that accompany CDW formation, indicating that these phonons couple strongly to the electronic degrees of freedom associated with the CDW. The same phonon bands, which represent internal vibrations of ${\mathrm{ZrTe}}_{3}$ prismatic rods, are suppressed at pressures above $\ensuremath{\sim}10\phantom{\rule{0.28em}{0ex}}\mathrm{kbar}$, indicating a loss of long-range order within the rods, specifically amongst intrarod Zr-Te bonds. These results suggest that the pressure-induced suppression of CDW order observed in ${\mathrm{ZrTe}}_{3}$ is structurally driven and provide insights into the origin of pressure-induced superconductivity in this material.
Dissecting microbial employment.

Abstract A targeted metagenomics approach profiles the methylotrophic microbes in lake sediments.
Inverting the selectivity of aquaporin 6: Gating versus direct electrostatic interaction

Specialized transmembrane proteins form channels that facilitate the transport of ions and other molecules across the membranes and thus play crucial role in many life processes. The understanding of these systems has increased enormously in recent years because of advances in structural and biochemical studies (e.g., refs. 1 and 2). However, key questions remain with regards to the exact factors that control the selectivity and gating of ion transport across membranes. To understand these factors, it would very useful to quantify the energy contributions that allow some ions to permeate while blocking others, and thus allow channels to fulfill their specific physiological functions. Although the availability of structural information paved the way for detailed scrutiny of different hypotheses and models, there is still a clear need for well defined experimental test cases. In this issue of PNAS, a study of aquaporin 6 (AQP6) by Liu et al. (3) provides a crucial test case in which a mutation of a single residue (a change of Asn-60 to Gly) completely changes the conductance, converting AQP6 from an anion channel to a water-selective channel. This finding provides extremely valuable information whose full “translation” to a functional model probably will require more structural information as well as the use of computer modeling approaches. This is not the first time that studies of the aqauporin family have provided a challenge and a guide to the understanding of ion selectivity. Most members of the aquaporin family allow water molecules to pass through membranes but block ions, including hydronium ions (2). The reason for the blockage of proton transport through aquaporin was the subject of recent studies (4–8 …
Information-theoretic evaluation of predicted ontological annotations.

Motivation: The development of effective methods for the prediction of ontological annotations is an important goal in computational biology, with protein function prediction and disease gene prioritization gaining wide recognition. Although various algorithms have been proposed for these tasks, evaluating their performance is difficult owing to problems caused both by the structure of biomedical ontologies and biased or incomplete experimental annotations of genes and gene products. Results: We propose an information-theoretic framework to evaluate the performance of computational protein function prediction. We use a Bayesian network, structured according to the underlying ontology, to model the prior probability of a protein’s function. We then define two concepts, misinformation and remaining uncertainty, that can be seen as information-theoretic analogs of precision and recall. Finally, we propose a single statistic, referred to as semantic distance, that can be used to rank classification models. We evaluate our approach by analyzing the performance of three protein function predictors of Gene Ontology terms and provide evidence that it addresses several weaknesses of currently used metrics. We believe this framework provides useful insights into the performance of protein function prediction tools. Contact: ude.anaidni@garderp Supplementary information: Supplementary data are available at Bioinformatics online.
A constraint oriented approach to inverse problems for kinematically redundant manipulators

Recently a number of measures of mechanism dexterity have been proposed in the robotics literature. These are defined as functions of the configuration, and are primarily promoted as criteria which should be optimized in the planning of robot motions. In this paper, a coordinate-free version of the manipulatability index is presented. This permits the index to be evaluated in a meaningful way for a (kinematically redundant) mechanism operating under imposed functional constraints on the joint variables. Such an intrinsic quantity is useful for deciding which of several possible constraints yields the best performance of a given mechanism, and conversely, it may be employed as a constraint oriented figure-of-merit in the design of kinematically redundant manipulators. It also provides a new computational tool for finding the singularitites inherent in most approaches to redundancy resolution by means of functional constraints.
Agouti/Melanocortin Interactions with Leptin Pathways in Obesity

The cloning of mouse obesity genes and their human homologues provides unique opportunities to identify novel cellular targets for therapeutic intervention. The first of these to be cloned, agouti, antagonizes central nervous system melanocortin receptor (MCR) binding, resulting in hyperphagia and an obesity/hyperinsulinemia syndrome. There appears to be significant crosstalk between the agouti and leptin signaling systems. Agouti antagonism of central nervous system (CNS) MCR binding inhibits the anorexic effects of leptin, whereas agouti up-regulates adipocyte leptin expression, serving to limit the magnitude of agouti-induced obesity. The effects of agouti and leptin mutations on obesity, however, are independent and additive. Agouti also regulates adipocyte lipid metabolism, functioning both to increase the expression and activity of lipogenic genes and to inhibit lipolysis. Both of these actions occur via a Ca2+-dependent mechanism, suggesting that modulation of adipocyte Ca2+ transport may be a key target for further investigation.
Information conveyed through brain-control: cursor versus robot

Microwire electrode arrays were implanted in the motor and premotor cortical areas of rhesus macaques. The recorded activity was used to control the three-dimensional movements of a virtual cursor and of a robotic arm in real time. The goal was to move the cursor or robot to one of eight targets. Average information conveyed about the intended target was calculated from the observed trajectories at 30-ms intervals throughout the movements. Most of the information about intended target was conveyed within the first second of the movement. For the brain-controlled cursor, the instantaneous information transmission rate was at its maximum at the beginning of each movement (averaged 4.8 to 5.5 bits/s depending on the calculation method used). However, this instantaneous rate quickly slowed down as the movement progressed and additional information became redundant. Information was conveyed more slowly through the brain-controlled robot due to the dynamics and noise of the robot system. The brain-controlled cursor data was also used to demonstrate a method for optimizing information transmission rate in the case where repeated cursor movements are used to make long strings of sequential choices such as in a typing task.
Antioxidant Treatment Prevents Renal Damage and Dysfunction and Reduces Arterial Pressure in Salt-Sensitive Hypertension

The goal of this study was to test the hypothesis that oxidative stress in Dahl salt-sensitive (SS) rats on a high-sodium intake contributes to the progression of renal damage, the decreases in renal hemodynamics, and the development of hypertension. We specifically studied whether antioxidant therapy, using vitamins C and E, could help prevent renal damage and glomerular filtration rate (GFR) and renal plasma flow reductions and attenuate the increases in arterial pressure. Thirty-three 7- to 8-week old Dahl SS/Rapp strain rats were placed on either a high-sodium (8%) or a low-sodium (0.3%) diet with or without vitamin E (111 IU/d) in the food and 98 mg/d vitamin C in the drinking water for 5 weeks. Rats were equipped with indwelling arterial and venous catheters at day 21. By day 35 in the rats with high-sodium diet, vitamin C and E treatment significantly decreased renal cortical and medullary O2*- release, mean arterial pressure, urinary protein excretion, glomerular necrosis, and renal tubulointerstitial damage. At this time, GFR significantly decreased in the high-sodium diet group (1.6+/-0.2 mL/min) when compared with either the high-sodium plus vitamins C and E (2.9+/-0.2 mL/min) or the low-sodium diet group (2.9+/-0.3 mL/min). In SS rats on high-sodium diet, renal plasma flow decreased 40%, and this reduced flow was restored by vitamin treatment. In Dahl salt-sensitive hypertension, increased oxidative stress plays an important role in the renal damage, decreases in renal hemodynamics, and increases in arterial pressure that occur. Antioxidant treatment with vitamins C and E improves renal dysfunction, lessens renal injury, and decreases arterial pressure in Dahl salt-sensitive hypertension.
Atmospheric CO2 enrichment alters energy assimilation, investment and allocation in Xanthium strumarium.

Summary • Energy-use efficiency and energy assimilation, investment and allocation patterns are likely to influence plant growth responses to increasing atmospheric CO2 concentration ([CO2]). Here, we describe the influence of elevated [CO2] on energetic properties as a mechanism of growth responses in Xanthium strumarium. • Individuals of X. strumarium were grown at ambient or elevated [CO2] and harvested. Total biomass and energetic construction costs (CC) of leaves, stems, roots and fruits and percentage of total biomass and energy allocated to these components were determined. Photosynthetic energy-use efficiency (PEUE) was calculated as the ratio of total energy gained via photosynthetic activity (Atotal) to leaf CC. • Elevated [CO2] increased leaf Atotal, but decreased CC per unit mass of leaves and roots. Consequently, X. strumarium individuals produced more leaf and root biomass at elevated [CO2] without increasing total energy investment in these structures (CCtotal). Whole-plant biomass was associated positively with PEUE. Whole-plant construction required 16.1% less energy than modeled whole-plant energy investment had CC not responded to increased [CO2]. • As a physiological mechanism affecting growth, altered energetic properties could positively influence productivity of X. strumarium, and potentially other species, at elevated [CO2].
STABILITY AND SPECIFICITY OF MEANING IN LIFE AND LIFE SATISFACTION OVER ONE YEAR

Meaning in life and life satisfaction are both important variables in well-being research. Whereas an appreciable body of work suggests that life satisfaction is fairly stable over long periods of time, little research has investigated the stability of meaning in life ratings. In addition, it is unknown whether these highly correlated variables change independent of each other over time. Eighty-two participants (mean age = 19.3 years, SD 1.4; 76% female; 84% European-American) com- pleted measures of the presence of meaning in life, the search for meaning in life, and life satisfaction an average of 13 months apart (SD = 2.3 months). Moderate stability was found for presence of mean- ing in life, search for meaning in life, and life satisfaction. Multiple regressions demonstrated specificity in predicting change among these measures. Support for validity and reliability of these variables is discussed.
Linear Versus Quadratic Amplitude Feedback in Active Control of Compressor Rotating Stall

Several issues that have been overlooked or only partially addressed in previous literature related to the active control of compressor rotating stall are clarie ed. This is accomplished via a detailed local stability analysis of the rotating stall inception point and the locally branched unstalled and stalled equilibria. The analysis is based on the e rst-term Galerkin approximation of the Moore ‐Greitzer model (Moore, F. K., and Greitzer, E. M., “ A Theory of Post-StallTransientsinAxialCompressorSystems,Part1,DevelopmentofEquations,”JournalofTurbomachinery , 1986), and it is valid for an arbitrary compressor map and a parabolic throttle characteristic. It is generically performed for a rather large class of throttle feedback control laws. Each such law is proportional to the rotating stall amplitude, raised to a strictly positive exponent. The proportionality constant is a nonnegative feedback gain. It is shown that linear feedback renders the rotating stall inception point and the neighboring stalled branch locally asymptotically stable for any value of the feedback gain. Quadratic feedback on the other hand represents a limiting case of control effectiveness and can at best lead to conditional local stability; that is, it can render the stall inception point and the neighboring stalled branch locally asymptotically stable only for sufe ciently high values of the feedback gain. Finally, sublinear feedback, namely, feedback with an exponent less than unity, not only unconditionally stabilizes the stall inception point and the neighboring stalled branch, but also completely smooths out any transition to rotating stall. These results extend and in some places contrast previous work on the subject that has dismissed such linear or sublinear feedback and concentrated mainly on quadratic feedback as a viable means of controlling compressor rotating stall.
AMPK-Mediated Inhibition of mTOR Kinase Is Circumvented during Immediate-Early Times of Human Cytomegalovirus Infection

Human cytomegalovirus (HCMV) infection increases synthetic rates in infected cells. The resulting increase in energy utilization could potentially increase the AMP:ATP ratio, causing activation of 5′-AMP-activated protein kinase (AMPK). Activated AMPK promotes inhibition of mammalian target of rapamycin (mTOR) kinase, which could be deleterious to the viral infection. Using the AMPK-activating drug 5-amino-4-imidazolecarboxamide ribose (AICAR), we showed that, by 12 h post-HCMV infection, inhibition of mTOR by AMPK is circumvented. However, growth curves showed that progeny virion production is inhibited when AICAR is added, suggesting other inhibitory effects of AICAR or activated AMPK.
Ionic Contamination-Humidity Effects on GaAs FETs

A study was made to determine the susceptibility to failure of present commercially available GaAs FETs as a result of the concurrent exposure to temperature cycling, high relative humidity, and ionic contamination. Devices with Al and Au/refractory gates from four different suppliers were studied. Devices with Au/refractory gates were less susceptible to degradation as a result of the hostile environment. Failure mechanisms were determined and correlated with the electrical degradation of the devices.
The effect of femoral and acetabular version on clinical outcomes after arthroscopic femoroacetabular impingement surgery.

Background: The impact of proximal femoral and combined femoral and acetabular version on patient-reported outcomes after arthroscopic surgery for femoroacetabular impingement (FAI) remains undefined. The purpose of this study was to identify associations of proximal femoral version as well as combined version (McKibbin index) with disease-specific, validated, patient-reported outcomes following arthroscopic correction of symptomatic FAI. Methods: A prospective hip arthroscopy registry was utilized to evaluate 243 patients who underwent arthroscopic surgery to correct FAI. Femoral version and the McKibbin index were measured prospectively on preoperative computed tomography scans. Disease-specific, patient-reported outcomes included the modified Harris hip score (mHHS) and the Hip Outcome Score (HOS) ADL (Activities of Daily Living) and Sports subscales. Disease impact on quality of life was determined with use of the International Hip Outcome Tool (iHOT-33). Comparative analyses were used to evaluate the impact of femoral version on changes in patient-reported outcome scores; multiple regression was used to adjust for potential confounders. Results: The patient cohort contained 243 patients (123 female and 120 male) with a mean age of 29.2 years and a mean postoperative follow-up of twenty-one months (range, twelve to forty-two months). The cohort experienced significant improvements (p < 0.001) in all patient-reported outcome measures, with most patients improving by at least the minimal clinically important difference for all of these measures. The mean improvement was 20 points for the mHHS, 15 for the HOS ADL, 23 for the HOS Sports, and 23 for the iHOT-33. When stratified by femoral version, the postoperative improvements in patients with relative femoral retroversion (<5° anteversion) were clinically important but of significantly smaller magnitude than those in the other version groups. We did not find any associations between the McKibbin index and any patient-reported outcomes. Conclusions: Although clinically important improvements can be expected after arthroscopic FAI surgery in all femoral version groups, patients with relative femoral retroversion (<5° femoral anteversion) may experience less improvement than those with normal or increased version. Level of Evidence: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.
Role of lanthanum in the gate stack: Co-sputtered TaLaN metal gates on Hf-based dielectrics

We examine the characteristics of TaLaN metal gates in direct contact with HfO"2 dielectric, in particular focusing on the effect of La in the gate stack for NMOS applications. Effective work functions (EWF) and vacuum work functions (WF) are measured as a function of lanthanum content in TaLaN without any intentional heating using X-ray photoelectron spectroscopy, U-V photoelectron spectroscopy, and electrical C-V measurements. We find that the addition of lanthanum to tantalum nitride lowered both the EWF and the WF of the metal gate by ~0.2eV and ~0.9eV, respectively. Furthermore, XPS indicates that lanthanum in TaLaN at the interface with HfO"2 is primarily bonded to nitrogen rather than oxygen and not reacting with the dielectric.