cssi/SciSciGPT-SciSciNet huggingface dataset:
High-performance liquid chromatographic determination of the stereoisomeric metabolites of ibuprofen.

Abstract A stereospecific reversed-phase high-performance liquid chromatographic (HPLC) method has been developed to simultaneously quantitate the stereoisomers of the two major metabolites of ibuprofen: hydroxyibuprofen and carboxyibuprofen. The metabolites were derivatized with S-(α)-methylbenzylamine to form diastereomeric amides which were separated and quantified on a C8 column. The validity of the stereoselective assay was confirmed by comparison with a non-stereoselective HPLC method. The stereoselective assay was applied to the quantification of all the stereoisomeric ibuprofen metabolites in urine from human volunteers dosed with racemic ibuprofen or the individual enantiomers of ibuprofen. Significant substrate and product stereoselectivities were observed in the formation of carboxyibuprofen.
Blowing model for turbulent boundary-layer dust ingestion

Abstract : The rate at which dust is ingested into a turbulent boundary layer is deduced for the case of a semi-infinite flat plate and for the boundary layer behind a moving shock wave. Conventional turbulent boundary-layer theory is used. It is assumed that the local dust-ingestion rate corresponds to the 'blowing' rate at which the local unblown surface shear C(f,0) is reduced to a value C(f,t) that is just sufficient to maintain surface particles in a mobile state. It is further assumed that the particle-velocity equilibration distance is small compared with the local boundary-layer thickness. It is found that erosion rate and boundary-layer thickness parameters are weakly (logarithmically) dependent on C(f,O)/C(f,t) and the maximum dust loading within the boundary layer is approximately equal to one. The theoretical predictions for local erosion rate, boundary thickness, and dust density are compared with the limited experimental results of Hartenbaum and Ausherman for the semi- infinite flat plate and moving-shock cases, respectively. Agreement within about a factor of two is obtained. Further comparison with experiment is recommended.
Effects of Diffraction and Partial Reflection in Multilayered Gradient Index Polymer Lenses

Multilayered gradient index polymer lenses are fabricated with many layers of polymers with different refractive indices. It is shown that, in principle, diffractive and reflective losses are <4 x 10-4for a typical lens.
Concentration of ACTH in Cavernous Sinus and Peripheral Blood Collected from Unanesthetized Sheep.

SummaryA simple technic for puncturing the cavernous sinus of unanesthetized sheep through the foramen ovale has been described. Cavernous sinus plasma showed at least a 2-fold greater concentration of ACTH than peripheral plasma collected simultaneously from the recurrent tarsal vein.The authors arc indebted to Priscilla Tippett for illustration and to Angela Boryczka, Roy Shackle-ford, and Vina Sera for technical assistance.
Pollination of the heterostylous Galápagos native, Cordia lutea (Boraginaceae)

The hypothesis of this study was that in the Galapagos Islands, fruit and seed set via nocturnal pollination would exceed that of diurnal pollination due to greater insect activity at night typical of hot, arid regions. Cordia lutea, a heterostylous member of the Galapagos flora, was submitted to pollination experiments, visitor observations, nectar sampling, pollen transfer studies, pollen-ovule ratio studies, and pollen measurements. Flowers set fruit and seed via open pollination, autonomous autogamy, facilitated autogamy, facilitated cross-pollination, diurnal pollination, and nocturnal pollination. There was a significant difference in fruit set between flowers experiencing legitimate cross-pollinations (pin × thrum) and those experiencing all other pollination treatments except facilitated autogamy. There was no significant difference in seed set among any of the treatments, but there was a trend toward greater seed set for flowers experiencing open-pollination, legitimate cross-pollination, and nocturnal pollination. There was no significant difference in fruit set or seed set between flowers experiencing diurnal pollination and nocturnal pollination, although there was a trend toward greater seed set resulting from nocturnal pollination. Carpenter bees were the most effective diurnal pollinators, whereas moths were the most effective nocturnal pollinators. Of the two, moths are more efficient at transporting pollen from plant to plant. Results indicate that an overall low productivity of this species is due to pollen limitation exacerbated by nectar robbing. Cordia lutea exhibits a mixed mating system, producing a relatively low level of fruits through a combination of self- and cross-pollination, facilitated by the relatively few insects that are available.
Reflections on rational choice—The existence of systematic irrationality

Abstract The behavioral challenge to the rational choice paradigm is oriented toward individual decision-making. Behavioral irrationality does not mean chaos. Most irrational behavior involves the exercise of reasoning. In reality, decision makers do not behave with full knowledge and/or optimal computational power in pursuit of maximizing expected utility. Besides reviewing critiques to the rationality paradigm for judgments and preferences and exploring the impact of culture on people's economic behavior, this paper is the first to call the attention of researchers to the phenomenon of systemic irrationality. Irrationality may exist at the aggregate or societal level, a conclusion based on the observation that large segments of the population are incapable of making decisions in accord with traditional rationality—groups such as those who have a psychiatric disorder, those who are taking medications, those with limited intelligence, those from the lower social classes, children and adolescents, and the elderly. Even those who are not included in the aforementioned groups, but who take medications for medical conditions may have their decision-making impaired to some extent. Therefore, it is argued that rationality in economic decision-making may be the exception rather than the norm.
Conflicts of Interest: A Case Study Exploring Constraints on Educational Leaders’ Agency as Representatives of Refugee Interests

School-aged children comprise 35–40 percent of the annual influx of new refugees. Yet, refugee parents have limited avenues of political representation until they attain citizenship. As the vanguard of government, schools offer refugee populations opportunities for representation through the agency of the educational leaders. Deploying surrogate representation as a theoretical lens, this case study explored how educational leaders represented the interests of the refugee populations they serve. Findings suggest that educational leaders’ agency is curtailed by: (1) rational agency in conflict with policy incentives, and (2) inaccurate assumptions about the refugee population's educational preferences and interest in participating in educational decision making.
Using cadmium-113 NMR spectrometry to study metal complexation by natural organic matter

Because of its relatively high natural abundance and the broad range of chemical shifts (900 ppm), 113Cd is a potentially excellent istope for NMR studies of metal binding sites of natural organic matter (NOM). This paper presents a 113Cd NMR study of the effects of pH and, to a lesser extent, Cd/C molar ratio on the complexation of cadmium ion by Suwannee River NOM. Spectra are presented for solutions ranging in pH from 3.6 to 9.0 and ranging in Cd/C ratio from 0.0013 to 0.0068. At acidic pH, a single somewhat sharp peak is observed, but more complex spectra are obtained at alkaline pH. These changes indicate that Cd−NOM exchange rates are much faster at acidic pH, where the concentration of free Cd2+ is greatest. Under nearly all the conditions of Cd/C ratio and pH that were used, Cd2+ is primarily coordinated by O donor atoms, probably in carboxyl groups. At high pH, some evidence of Cd2+ coordination by N donor atoms is observed. No evidence of Cd2+ ions coordinated by S donor atoms was observed in th...
High-pressure synthesis of high-purity diamond crystal

Abstract High-purity type IIa diamond crystals of weight 1–2 carats, containing less than 0.1 ppm chemical impurities and few inclusions, have been successfully synthesized by a temperature gradient method at high pressures and temperatures. The concentration of nitrogen impurities in the diamond crystals was reduced to less than 0.1 ppm by adding an element of the IVa group to the solvent as a nitrogen getter. The boron impurity concentration was reduced to less than 0.1 ppm by using a high-purity graphite (
EXAMINING TEST ITEMS FOR DIFFERENTIAL DISTRACTOR FUNCTIONING AMONG STUDENTS WITH LEARNING DISABILITIES

This study examined whether distractor choices functioned differently for students without learning disabilities than they functioned for students with learning disabilities who received no accommodation, students with learning disabilities who received a read-aloud accommodation, and students with learning disabilities who received some form of accommodation other than read-aloud. The study's purpose was twofold: (a) to examine the results of the DDF analysis to determine whether the distractors functioned differently for the various groups of students and (b) to aid in determining whether the test may be modified for those students with learning disabilities by removing a distractor while maintaining adequate test validity and information.
Generation expansion planning under uncertainty with emissions quotas

Abstract Generation expansion planning for hydro-thermal power systems aims to find optimal investment decisions among a set of possible power plant projects. For any given investment plan, expansion planning models must account for investment costs as well as expected operational costs. Additionally, when modeling hydro-thermal power systems, one must consider the inherent uncertainty in hydro inflows because variations in inflows can significantly impact operational decisions. To model the expansion planning problem for a hydro-thermal power producer, we propose a novel decomposition algorithm, based on Benders decomposition. The Benders master problem computes the investment decisions while the separation problems are emissions-constrained, least-cost, and stochastic hydro-thermal scheduling problems. The separation problems are solved using a standard stochastic dual dynamic programming (SDDP) algorithm. To demonstrate the effectiveness of the approach, we present a case study for Panama's power system. The computational results allow us to price carbon dioxide emissions reductions, aiding the evaluations of environmental policies.
Current Operators and Majorana Equation for the Hydrogen Atom from Dynamical Groups

It is proved that the dipole operator in the hydrogen atom is the product of an element in the Lie algebra and of a group element of the conformal group $O(4, 2)$. A relativistic wave equation containing the total momentum only is set up which describes the internal structure of the system purely group theoretically and gives the correct mass spectrum. The diagonalization of this equation determines a new basis of states in which the dipole operator is simply an element of the Lie algebra. The angle of transformation to the new basis is evaluated to be $\ensuremath{\theta}=2invtan(1\ensuremath{-}\frac{\ensuremath{\epsilon}}{n})$, or, $\ensuremath{\theta}=log(\frac{2n}{\ensuremath{\epsilon}})$, where $n$ is the principal quantum number and $\ensuremath{\epsilon}$ is essentially the fine-structure constant.
Immiscible lipids control the morphology of patchy emulsions

We study the phase behavior of immiscible mixtures of phospholipids and cholesterol at the interface of oil-in-water emulsions, which governs the surface morphology of patchy droplets. Emulsification with lipid mixtures leads to domain formation with a variety of shapes, such as spots, disordered stripes, hemispheres and rings. We map out the ternary immiscibility diagram of our system, which allows one to control the geometry of patches on the droplet surface. By contrast to short-lived domains on liposomes, image analysis of the individual domains shows that emulsion spots grow towards a steady state size distribution and remain stable over weeks. These domains are functionalized with biotinylated lipids, which makes them useful candidates for directed self-assembly through specific interactions via streptavidin. Here we bind streptavidin coated beads to these lipids and find that the binder diffusion constant depends on the morphology of the droplet. These fluid patchy particles offer a versatile system in which the geometry and the dynamics of the sticky patches are under control.
Glucose-regulated insulin production in the liver improves glycemic control in type 1 diabetic mice

Objective Type 1 diabetes results from autoimmune destruction of beta-cells in the pancreas. Our objective is to reconstitute a glucose-responsive system in the liver to regulate hepatic insulin production for improving glycemic control in type 1 diabetes.
Transgenic mice expressing β-galactosidase in mature neurons under neuron-specific enolase promoter control

Abstract To gain insights into transcription factors defining neuronal identity, we generated transgenic mice carrying a 1.8 kb rat neuron-specific enolase (NSE) promoter fragment fused to an E. coli lacZ gene. Four of seven transgenic families expressed transgene RNA in the nervous system but not in most other tissues. Histochemical analysis of adult brain from the two lines with highest lacZ mRNA levels showed neuron-specific, pan-neuronal β-galactosidase activity. Developmental RNA and histochemical analyses showed parallel onset of transgene and endogenous NSE gene expression in various neuronal cell types, although the magnitude of NSE mRNA accumulation later in development was not matched by the transgene. These results suggest that cis -acting regulatory elements, subject to neuron-specific control, are located within 1.8 kb upstream from the NSE gene.
A probabilistic estimation framework for predictive modeling analytics

IBM ProbE (for probabilistic estimation) is an extensible, embeddable, and scalable modeling engine, particularly well-suited for implementing segmentation-based modeling techniques, wherein data records are partitioned into segments and separate predictive models are developed for each segment. We describe the ProbE framework and discuss two key business solutions that have been built using ProbE: the IBM Underwriting Profitability Analysis for insurance risk management, and the IBM Advanced Targeted Marketing for Single Events for direct mail database marketing.
The Inexact Science of Congressional Redistricting

Incumbent politicians are understandably nervous when electoral rules are altered. In the case of the U.S. House of Representatives, members are well aware that a change in decade is accompanied by the near certainty that their own district lines will be redrawn. These incumbents know that changes resulting from the reallocation of congressional seats among states and the shift of population within states could have a shattering effect on their careers: their districts could be eliminated; they could be thrown into a district with another House incumbent; their district lines could be radically redrawn, destroying their traditional bases of support.
Observations of shear-augmented diffusion processes and evaluation of effective diffusivity from current measurements in Corpus Christi Bay

Abstract Studies on the process of diffusion in fluids have shown that in the presence of a shear structure within the current field, the observed spreading of a marked fluid can be augmented significantly. Shear-diffusion becomes the dominant diffusion process after a time Tn, the initialization time has elapsed. Given the existence of a vertical shear structure within the flow field, the characteristic vertical mixing time, Tc having an inverse relation to vertical turbulent diffusivity, Kz governs this initialization time. This study focuses on the observation of shear-augmented diffusion process in a shallow wind-driven body of water leading up to the development of numerical algorithms for obtaining an effective diffusivity, Ke from shear-current measurements at spatial scales ∼1000 m. This was part of a series of dye-tracer experiments conducted in Corpus Christi Bay, Texas. Numerical estimates are provided for Tn using the value of Kz determined from the temporal current fluctuations based on velocity correlation function, Rτ of the velocity time-series. An algorithm was developed by discretization of an equation of the form K i = u i ′ 2 ¯ T c I i (i=x,y) which was then used in the evaluation Ke based on numerical estimates of Tc and the shear coefficient Ii. It was found that in the presence of shear-current structure, predicted Ke values along two orthogonal directions were ∼104 and 105 cm2/s, respectively, about 10–20 times higher than estimates obtained based on turbulence alone and confirmed through visual observations and statistical estimates of the size of the diffusing dye cloud.
Temporary Integration, Resilient Inequality: Race and Neighborhood Change in the Transition to Adulthood

This article focuses on neighborhood and geographic change arising with the first "selection" of an independent residential setting: the transition out of the family home. Data from two sources-the Project on Human Development in Chicago Neighborhoods, and the Panel Study of Income Dynamics-are used to provide complementary analyses of trajectories of change in geographic location and neighborhood racial and economic composition during young adulthood. Findings indicate that for young adults who originate in segregated urban areas and remain in such areas, the period of young adulthood is characterized by continuity in neighborhood conditions and persistent racial inequality from childhood to adulthood. For young adults who exit highly segregated urban areas, this period is characterized by a substantial leveling of racial inequality, with African Americans moving into less-poor, less-segregated neighborhoods. However, the trend toward racial equality in young adulthood is temporary, as the gaps between whites and blacks grow as the young adults move further into adulthood. Crucial to the reemergence of racial inequality in neighborhood environments is the process of "unselected" change, or change in neighborhood conditions that occurs around young adults after they move to a new neighborhood environment.
QUALITATIVE RESEARCH AND THE LEGITIMIZATION OF KNOWLEDGE

Reservatinos about qualitative research often center around contentions that, since qualitative methods are so subjective and uncontrolled, the results of qualitative research are not valid and reliable. While many qualitative researchers in education have attempted to improve the trustworthiness of their results by making their methods more systematic, we argue that qualitative researchers cannot establish the trustworhiness of their findings, regardles of the methods they use. Rather, the legitimization of knwoledge requires the judgement of an entire community of stakeholders. In the absence of certainty, knowledge is an ethical matter, one in which the judgement of each stakeholder must count.
Irish writing characteristics

A discussion of Irish writing instruction from the 1920s to present and a look at some of the more distinguishing features in the written hand.
Evidence Sets: Modeling Subjective Categories

Zadeh's Fuzzy Sets are extended with the Dempster-Shafer Theory of Evidence into a new mathematical structure called Evidence Sets, which can capture more efficiently all recognized forms of uncertainty in a formalism that explicitly models the subjective context dependencies of linguistic categories. A belief-based theory of Approximate Reasoning is proposed for these structures. Evidence sets are then used in the development of a relational database architecture useful for the data mining of information stored in several networked databases. This useful data mining application establishes an Artificial Intelligence model of Cognitive Categorization with a hybrid architecture that possesses both connectionist and symbolic attributes.
Conceptual Challenges in Poverty and Inequality: One Development Economist's Perspective *

The last thirty years in the analysis of inequality and poverty, especially in developing countries, has seen two phases —a phase of conceptual advancement, followed by a phase of application and policy debate. Both phases were exciting and useful in their own way, but the applied phase has significantly exhausted the potential of the conceptual advances of two decades ago, and new advances have been few and far between. However, there is now a need, and an opening, for a new phase of conceptual advances, advances that will make use of shifting methodological terrain in mainstream economics, and that will answer emerging policy questions that would otherwise have no easy answers (or, perhaps, too easy answers).
Metacognitive awareness of learning strategies in undergraduates

Two studies examined undergraduates’ metacognitive awareness of six empirically-supported learning strategies. Study 1 results overall suggested an inability to predict the learning outcomes of educational scenarios describing the strategies of dual-coding, static-media presentations, low-interest extraneous details, testing, and spacing; there was, however, weak endorsement of the strategy of generating one’s own study materials. In addition, an independent measure of metacognitive self-regulation was correlated with scenario performance. Study 2 demonstrated higher prediction accuracy for students who had received targeted instruction on applied memory topics in their psychology courses, and the best performance for those students directly exposed to the original empirical studies from which the scenarios were derived. In sum, this research suggests that undergraduates are largely unaware of several specific strategies that could benefit memory for course information; further, training in applied learning and memory topics has the potential to improve metacognitive judgments in these domains.
THE TAKEN-FOR-GRANTED

This essay constitutes a theoretical account of how speakers interpret that which is taken for granted in messages. It is argued that the term “taken for granted” (TFG) is useful in reconsidering research concerning enthymemes, argument theory, indirect speech acts, conversational maxims, pragmatic implication, and a number of other areas. When combined with materials from the symbolic interactionist literature on alignment, the TFG concept provides a framework for a model of how speakers interpret unspoken portions of utterances.
Bromide Interference: Is Less Really Better?

Increased serum bromide may result from the ingestion of various drugs and from environmental exposures. Chloride methods that are less susceptible to bromide interference have a clinical disadvantage in that they are less likely to arouse suspicion in cases of bromide toxicity. When there is a clinical suspicion of bromide toxicity, differences among various analyzers in the amount of interference caused by bromide may be exploited to confirm this suspicion and to estimate the concentration of bromide in serum.
Human Immunodeficiency Virus Matrix Tyrosine Phosphorylation: Characterization of the Kinase and Its Substrate Requirements

During virus assembly, a subset of human immunodeficiency virus (HIV) matrix (MA) molecules is phosphorylated on C-terminal tyrosine. This modification facilitates infection of nondividing cells by allowing for the recruitment of the karyophilic MA into the viral core and preintegration complex. MA tyrosine phosphorylation is accomplished by a cellular protein kinase which is incorporated into virions. In this study, we have investigated the nature of this enzyme as well as the determinants of MA necessary for its phosphorylation. Employing an in vitro kinase assay, we found that the MA tyrosine kinase activity is present in various cultured cell lines including CEM and SupT1 T-lymphoid cells, Namalwa B cells, 293 and CV-1 kidney fibroblasts, and P4 HeLa cells. In addition, it could be detected in platelets, macrophages, and activated peripheral blood lymphocytes (PBLs) but not in erythrocytes and resting PBLs isolated from human blood. Subcellular localization of the kinase activity by cell fractionation demonstrated that it is enriched in cellular membranes. In HIV type 2 (HIV-2) particles, the MA tyrosine kinase is associated with the inner leaflet of the viral membrane, while the tyrosine-phosphorylated MA is localized to the core. Individual mutations of each of the last eight residues immediately upstream of the C-terminal tyrosine (Y132) of HIV-1 MA did not prevent Y132 phosphorylation, suggesting that the kinase does not require a highly specific sequence adjacent to the C-terminal tyrosine. Confirming this, we found that the MA of murine leukemia virus, the sequence of which is only moderately homologous to that of HIV-1 and HIV-2 MA, is also C-terminally tyrosine phosphorylated.
Inferring Identity Using Accelerometers in Television Remote Controls

We show that accelerometers embedded in a television remote control can be used to distinguish household members based on the unique way each person wields the remote. This personalization capability can be applied to enhance digital video recorders with show recommendations per family-member instead of per device or as an enabling technology for targeted advertising. Based on five 1-3 week data sets collected from real homes, using 372 features including key press codes, key press timing, and 3-axis acceleration parameters including dominant frequency, energy, mean, and variance, we show household member identification accuracy of 70-92% with a Max-Margin Markov Network (M3N) classifier.
Bayesian Threshold Estimation

Bayesian estimation of a threshold time (hereafter simply threshold) for the receipt of impulse signals is accomplished given the following: 1) data, consisting of the number of impulses received in a time interval from zero to one and the time of the largest time impulse; 2) a model, consisting of a uniform probability density of impulse time from zero to the threshold, and constituting the probability density from which the data impulses are drawn randomly and independently; and 3) a prior probability density of threshold which is linear from a positive initial threshold to one and that is zero otherwise, or which is uniform from zero to one. The posterior probability density of threshold is found with the number of impulses, the time of the largest time impulse, and the initial threshold as parameters, and with the first two parameters fixed, the initial threshold is found that maximizes the entropy of the posterior probability density. It is shown that for some values of initial threshold, including the value that maximizes entropy, the following three estimates of threshold from the posterior probability density are all different: the maximum (maximum a posteriori or MAP estimate), the mean (mean squared error or MMSE estimate), and the maximum for a uniform prior probability density (maximum likelihood or ML estimate). This easily understood and practical Bayesian threshold estimation problem has two aspects of pedagogical interest: 1) the problem is unusual in that the MAP, MMSE, and ML estimates are generally different-in typical problems with Gaussian or uniform models and prior probability densities, at least two of these three estimates are equal; 2) the problem constitutes a clear illustration of how an unknown parameter in the prior probability density (here, initial threshold) may be specified so as to achieve a desired property for the posterior probability density (here, maximum entropy).
THE APPLICATION OF DISCRETE CHOICE MODELS TO WILDLIFE RESOURCE SELECTION STUDIES

This paper introduces the theory and application of discrete choice models to resource selection studies. Discrete choice models calculate the probability of an individual selecting a resource as a function of the attributes of that resource and all other available resources. The data for these attributes may be continuous or categorical. When availability is the same for all individuals and only two resources are available, the multinomial logit discrete choice model reduces to the logistic model. Discrete choice models and advances in GIS technology give the researcher flexibility in defining resource availability separately for each individual over time and space. The output of the discrete choice approach also provides managers with a tool to explore the effects of potential management actions and provides researchers with new hypotheses deserving of further investigation. To illustrate the application of discrete choice models to resource selection studies, we present a case study of summer diurnal bed site selection by elk (Cervus elaphus) in Custer State Park, South Dakota, United States. The results demonstrate the importance of factors relating to thermal regulation, hiding cover, and potentially forage, in elk bed site selection in this region.
Io and Jupiter: The volcano-magnetosphere connection

In the interlude between spacecraft encounters with Jupiter, Earth-bound observers using clever and powerful techniques have made substantial headway in monitoring two major phenomena: volcanos on Jupiter's moon Io (most active in the solar system) and Jupiter's magnetosphere (largest and densest of all the planets). While these two may seem unrelated, planetary scientists believe they are quite closely tied. Astronomers are working together to probe the fundamental and enigmatic connection between volcanos and magnetospheres. Volcanic activity on Io is powered not by radioactive heating, as it is on Earth, but by the continual flexing of Io by Jupiter's intense gravitational field, which generates heat as in a rapidly flexed tennis ball. Most of this heat is eventually radiated into space from a series of hot volcanic centers, or “hot spots,” where the surface is up to several hundred degrees hotter than its surroundings. The heat radiation is so intense that Io literally “glows in the dark” at infrared wavelengths, allowing astronomers with infrared telescopes to follow the frequent changes in the level of volcanic activity.
Evaluation of a reversed-phase column (Supelcosil LC-ABZ) under isocratic and gradient elution conditions for estimating octanol–water partition coefficients

The solvation parameter model is used to identify suitable chromatographic models for estimating the octanol–water partition coefficient for neutral compounds of varied structure by reversed-phase liquid chromatography. The stationary phase Supelcosil LC-ABZ with methanol–water mobile phases affords a series of suitable correlation models for estimating the octanol–water partition coefficient (log KOW) under isocratic and gradient elution conditions. Isocratic separations with mobile phase compositions containing from about 25 to 40% (v/v) methanol provide the most accurate results for log KOW values in the range −0.1 to 4.0. Gradient separations programmed from 5 to 100% (v/v) methanol are suitable for faster separations of compounds with large log KOW values. The standard error in the estimate for the regression models of the predicted log KOW values against literature values are 0.135 log units for the 30% (v/v) methanol–water isocratic system and 0.263 log units for the methanol–water gradient system. Isocratic retention factors predicted from two gradient separations with gradient times of 15 and 45 min afford a poorer fit for the correlation models between log KOW and the estimated retention factors than that of either the above isocratic and gradient models. Plots of the retention factor (log k) as a function of mobile phase composition are generally non-linear. Values of log kW obtained by non-linear extrapolation to a volume fraction of 0% (v/v) methanol do not afford a useful model for estimating log KOW.
Correlates of Attention in a Model of Dynamic Visual Recognition

Given a set of objects in the visual field, how does the the visual system learn to attend to a particular object of interest while ignoring the rest? How are occlusions and background clutter so effortlessly discounted for when recognizing a familiar object? In this paper, we attempt to answer these questions in the context of a Kalman filter-based model of visual recognition that has previously proved useful in explaining certain neurophysiological phenomena such as endstopping and related extra-classical receptive field effects in the visual cortex. By using results from the field of robust statistics, we describe an extension of the Kalman filter model that can handle multiple objects in the visual field. The resulting robust Kalman filter model demonstrates how certain forms of attention can be viewed as an emergent property of the interaction between top-down expectations and bottom-up signals. The model also suggests functional interpretations of certain attention-related effects that have been observed in visual cortical neurons. Experimental results are provided to help demonstrate the ability of the model to perform robust segmentation and recognition of objects and image sequences in the presence of varying degrees of occlusions and clutter.
ML and Bayesian impulse restoration based object recognition in photon limited noise

In this paper two new object recognition and localization approaches are proposed in photon-limited noise. These approaches are based on ML and Bayesian impulse restoration (IR). For the ML approach, the expectation-maximization (EM) algorithm followed by non-linear filtering that highlights impulses is used. For the Bayesian approach, a novel prior that captures the impulsive nature of the desired solution is proposed and an extension of the EM algorithm is used to find the solution. The localization receiver operating characteristics (LROC) curve is used to quantify the performance of the proposed algorithms. Numerical experiments of an extensive Monte-Carlo study are presented. These experiments demonstrate that the proposed ML-IR approach is superior to traditional likelihood ratio detection approaches for this problem. Furthermore, they also demonstrate that the proposed Bayesian-IR framework outperforms its ML counterpart.
OCDMA-coded free-space optical links for wireless optical-mesh networks

We propose a wireless optical-mesh network based on optical code-division multiple-access (OCDMA)-coded free-space optical links. The performance of the proposed network under intermediate and strong turbulence channel conditions is investigated for synchronous and asynchronous OCDMA. We show that synchronous OCDMA using complementary Walsh-Hadamard codes operating at a raw bit rate of 622 Mb/s per user can achieve a bit-error rate of 10/sup -9/. This is achievable in channels with strong turbulence and high temporal correlation, or in channels with intermediate turbulence conditions; reasonable conditions based on channel characteristics inferred from the refractive index spectrum. For asynchronous OCDMA using optical orthogonal codes (OOCs), using a lower bound, we show that asynchronous OCDMA using OOCs cannot achieve acceptable performance for the same channel conditions, due to interference limitations.
A Completely Integrated Low Jitter CMOS PLL for Analog Front Ends in Systems on Chip Environment

This paper describes the PLL designed for the analog front-end of the silicon tuner in the cable modem system. The PLL is used to generate clocks (150-175MHz) for the DAC and hence the phase noise (jitter) requirement is very aggressive (15ps rms, which is less than 1 degree of integrated phase error). Low noise design for all the main blocks was a key to achieve this. Care was taken to reduce reference spurs and supply/substrate injected spurs. The PLL uses two supplies. Charge pump and voltage controlled oscillator (VCO) work off a 3.3V analog supply as it can give maximum VCO control voltage compliance, which helps reduce VCO gain, and hence reference and supply/substrate induced spurs. The digital part works off 1.8V supply as 1.8V core transistors give fastest switching which reduces phase noise in the dividers. The 3.3V to 1.8V interfaces have been optimized for the desired edges of output clock and phase comparison clock so that they have minimum contribution to phase error. Optimum loop bandwidth, PSRR and supply filtering were achieved to minimize phase noise and spurious modulation. The reference spur has been reduced by minimizing charge and clock feedthrough in the charge pump, and using a fourth order loop filter. The VCO is a differential current-starved ring oscillator. The VCO stages have large signal swing and large Gm to minimize the phase noise.
Path-based encoding efficiency of wavelet-based compressed imagery

This paper presents a method for testing the performance of different path-based coders of wavelet transformed imagery. Path-based coders are very popular techniques for compressing wavelet-transformed imagery, but there has been little knowledge formally documented on the most efficient method of path traversal for the coding process. Thus, this paper presents the findings of several performance tests using two path-based coding techniques. These techniques are used to independently code each subband of several wavelet transformed images using different coding paths in each test. The results are documented and give rise to conclusions on how to best traverse each subband in a wavelet-transformed image for most efficient coding
Effects of sandblasting and silica-coating procedures on pure titanium

Silica coating titanium improves chemomechanical bonding. Sandblasting is recommended as a pretreatment to thermal silica coating (Silicoater MD) or as part of a tribochemical silica coating process (Rocatec). This study evaluated the effects of sandblasting and coating techniques on volume loss, surface morphology and composition changes in pure titanium. Volume loss of titanium was similar to values reported for base alloys and does not seem to be critical for the clinical fit of restorations. Embedded alumina particles were found in the titanium after sandblasting and the alumina content increased to a range of 27.5-39.3 wt% as measured by EDS. Following tribochemical silica coating, a layer of small silica particles remained on the surface, increasing the silica content to a range of 17.9-19.5 wt%. Ultrasonic cleaning removed loose alumina or silica particles from the surface, resulting in only slight decreases in alumina or silica contents, suggesting firm attachment of most of the alumina and silica to the titanium surface. Silica content following thermal silica coating treatment increased only slightly from the sandblasted specimen to 1.4 wt%. The silica layer employed by these silica coating methods differs widely in both morphology and thickness. These results provide a basis for explanation of adhesive failure modes in bond strength tests and for developing methods to optimize resin bonding. Clinically, ultrasonic cleaning of sandblasted and tribochemically silica coated titanium should improve resin bonding as loose surface particles are removed without relevant changes in composition.
Classifying High-Dimensional Text and Web Data Using Very Short Patterns

In this paper, we propose the "democratic classifier", a simple pattern-based classification algorithm that uses very short patterns for classification, and does not rely on the minimum support threshold. Borrowing ideas from democracy, our training phase allows each training instance to vote for an equal number of candidate size-2 patterns. The training instances select patterns by effectively balancing between local, class, and global significance of patterns. The selected patterns are simultaneously added to the model for all applicable classes and a novel power law based weighing scheme adjusts their weights with respect of each class. Results of experiments performed on 121 common text and Web datasets show that our algorithm almost always outperforms state of the art classification algorithms, without any parameter tuning. On 100 real-life Web datasets, the average absolute classification accuracy improvement was as great as 9.4% over SVM, Harmony, C4.5 and KNN. Also, our algorithm ran about 3.5 times faster than the fastest existing pattern-based classification algorithm.
Spatial Prediction of Landslide Hazard Using Logistic Regression and ROC Analysis

An empirical modeling of road related and non-road related landslide hazard for a large geographical area using logistic regression in tandem with signal detection theory is presented. This modeling was developed using geographic information system (GIS) and remote sensing data, and was implemented on the Clearwater National Forest in central Idaho. The approach is based on explicit and quantitative environmental correlations between observed landslide occurrences, climate, parent material, and environmental attributes while the receiver operating characteristic (ROC) curves are used as a measure of performance of a predictive rule. The modeling results suggest that development of two independent models for road related and non-road related landslide hazard was necessary because spatial prediction and predictor variables were different for these models. The probabilistic models of landslide potential may be used as a decision support tool in forest planning involving the maintenance, obliteration or development of new forest roads in steep mountainous terrain.
Influence of Body Size on Dietary Nutrition of White-Tailed Deer Odocoileus virginianus

Abstract Intraspecific competition is one of the major factors that can have an effect on the resources utilized within a habitat. Differences in diet quality of selected forage have been noted in size-dimorphic ungulates. However, on an intraspecific basis, data demonstrating a body size influence on diet quality are lacking. We examined diet quality across a range of body masses (14–76 kg) in white-tailed deer Odocoileus virginianus (n = 108) in a 2,628-ha enclosure at Kerr Wildlife Management Area, Kerr County, Texas, USA. The quality of the diet consumed was determined by crude protein, acid detergent fiber, and neutral detergent fiber content of digesta in the rumen–reticulum. Results indicated that in relation to body mass, the ratio of crude protein to acid detergent fiber was greater for smaller bodied white-tailed deer. By consuming a diet higher in crude protein than did large bodied individuals, small-bodied individuals should meet their high mass-specific metabolic demands more efficiently. ...
Responses of plant populations and communities to environmental changes of the late Quaternary

The environmental and biotic history of the late Quaternary represents a critical junction between ecology, global change studies, and pre-Quaternary paleobiology. Late Quaternary records indicate the modes and mechanisms of environmental variation and biotic responses at timescales of 101–104 years. Climatic changes of the late Quaternary have occurred continuously across a wide range of temporal scales, with the magnitude of change generally increasing with time span. Responses of terrestrial plant populations have ranged from tolerance in situ to moderate shifts in habitat to migration and/or extinction, depending on magnitudes and rates of environmental change. Species assemblages have been disaggregated and recombined, forming a changing array of vegetation patterns on the landscape. These patterns of change are characteristic of terrestrial plants and animals but may not be representative of all other life-forms or habitats. Complexity of response, particularly extent of species recombination, depends in part on the nature of the underlying environmental gradients and how they change through time. Environmental gradients in certain habitats may change in relatively simple fashion, allowing long-term persistence of species associations and spatial patterns. Consideration of late Quaternary climatic changes indicates that both the rate and magnitude of climatic changes anticipated for the coming century are unprecedented, presenting unique challenges to the biota of the planet.
The Autonomy of the (Syntactic) Lexicon and Syntax: Insertion Conditions for Derivational and Inflectional Morphemes

A central concern of western grammar has always been the proper characterization of what can be called non-finite verbal constructions: the infinitive, the gerund, and the participle. Under the aegis of generative grammar, progress toward this goal has been swift, in comparison to what went before; the principal clarifications will be outlined just below.
Discrete angle biasing in Monte Carlo radiation transport

An angular biasing procedure is presented for use in Monte Carlo radiation transport with discretized scattering angle data. As in more general studies, the method is shown to reduce statistical weight fluctuations when it is combined with the exponential transformation. This discrete data application has a simple analytic form that is problem independent. The results from a sample problem illustrate the variance reduction and efficiency characteristics of the combined biasing procedures, and a large neutron and gamma-ray integral experiment is also calculated. A proposal is given for the possible code generation of the biasing parameter rho and the preferential direction ..cap omega../sub 0/ used in the combined biasing schemes.
Indirect pulse shaping by parametric transfer

There has been much recent interest in generating mid-infrared (MIR) shaped pulses, useful for various applications such as extending ultrafast coherent control studies to vibrational systems of molecules of chemical and biological interests. Although high resolution pulse shaping capabilities exist for the visible and near-infrared (NIR) wavelengths [1, 2], direct phase and amplitude pulse shaping in the MIR has yet to be demonstrated. The main difficulty is the lack of appropriate materials for the usual direct methods of pulse shaping. Liquid crystal modulators absorb in the MIR; acousto-optic materials such as TeO2 and GaP, though transparent, have very low diffraction efficiency. One solution is to shape pulses in the visible or near-infrared wavelengths and transfer the shape to a pulse of another wavelength by a nonlinear optical process. There have been some recent successes in this approach[3]. However, in all these cases the shaped pulses are the result of nonlinear optical process between two pulses with similar bandwidth, and the resolution of the final pulse shape may be limited as it is a non-trivial convolution between the two input pulses. On the other hand, an OPA process pumped by a narrower spectral bandwidth pulse can effect a high fidelity transfer of a broadband pulse shape to another pulse of a different wavelength. We demonstrate this principle by generating complex high resolution shaped pulses with considerable pulse energy at NIR by a β-barium borate (BBO) based noncollinear optical parametric amplification (NOPA)[4] of visible shaped pulses [5]. We also demonstrate, for the first time to our knowledge, that with similar principles, a potassium niobate (KNB) based NOPA can amplify NIR shaped pulses with high fidelity and thereby obtaining MIR (3−4 µm) shaped pulses.
Interior Permanent Magnet Machine

An interior permanent magnet machine includes a stator including a plurality of electrical conductors. The interior permanent magnet machine further includes a rotor concentrically disposed in relation to the stator. The rotor is configured to rotate relative to the stator about a rotational axis and includes a plurality of polar pieces arranged annularly about the rotational axis. At least one of the polar pieces includes a magnetic layer configured to magnetically interact with the electrical conductors. The magnetic layer has a substantially conic section shape.