cssi/SciSciGPT-SciSciNet huggingface dataset:
An anthropomimetic approach to high performance traction control

The ability to learn and adapt to changing environmental conditions, as well as develop perceptive models based on stimulus-response data, provides expert human drivers with significant advantages. When it comes to bandwidth, accuracy, and repeatability, automatic control systems have clear advantages over humans; however, most high performance control systems lack many of the unique abilities of a human expert. This paper documents our first step toward the development of a novel automatic traction control algorithm using an anthropomimetic approach. The primary objective of this approach was to synthesize a high performance longitudinal traction control system by incorporating desirable human behavior distilled from human-in-the-loop (HIL) testing on a 6-DOF driving simulator. The proposed control algorithm was developed in a general framework, and applied to the specific task of longitudinal traction control. Simulation results confirm that the proposed anthropomimetic traction control algorithm provides improved performance relative to a well-tuned conventional PID-based traction control algorithm. Results are also compared with the HIL response data from a behavioral study.
Critical properties of many-component systems

Critical properties are discussed for systems with order parameters given by n vectors S/sub a/, each with m components. The Hamiltonian has an arbitrary symmetry for each vector separately, but there is a particular kind of coupling between them. It is shown that there is an integral representation for the partition function which reduces n to an explicit parameter in an averaged partition function for the m-component model. This leads to a simple discussion of properties of the system as a function of n. In particular, it is possible to give a coherent derivation of several known and new results without the aid of perturbation theory or the renormalization-group method. It is shown that, in certain special cases, the exponents are Gaussian when n is a negative even integer and that n = 0 corresponds to the excluded-volume problem. The general case is shown to reduce to an arbitrary m-component model which is random when n = 0 and constrained when n ..-->.. infinity. A direct derivation of the large-n limit is given and leads to a variety of exactly solvable models. Expressions for the order n/sup -1/ correction are obtained in terms of correlation functions. This expansion is validmore » at all temperatures and for any order of transition, so that it is particularly suitable for considering tricritical phenomena. (auth)« less
Particle Size Classification of Glass Particles Using Aerodynamic Jet Vectoring

An experimental demonstration of a new, non-contact particle characterization technique called Aerodynamic Vectoring Particle Sorting (AVPS) is presented. AVPS uses secondary blowing and suction control flows–flows that are a fraction of the jet flow rate–to sharply change the direction of a planar, particle-laden jet. As the jet is vectored, particles present in the flow experience a resultant drag force, dependent upon their size, that balances inertia. Since this balance determines the particle's trajectory, vectoring the flow leads to a separation of particles downstream. This simple, low-pressure-drop sorting technique classifies particles with less risk of damage or contamination than currently available sorting devices. Particles from 10–40 μm and 2.5 times the density of water have been sorted to an accuracy of 1.5 μm. Sorting of heavy particles such as these is accomplished at very low speeds, reducing the tendency of damage to the particles. Lighter particles are sorted at higher speeds. Particles from 5–40 μm and 0.6 times the density of water were sorted to an accuracy of 6.6 μm. AVPS is also shown to be capable of concentrating aerosols. Our measurements indicate that an air sample containing water-like particles can be concentrated by a factor of 10 using AVPS.
Feigning neuropsychological impairment: A critical review of methodological and clinical considerations.

Abstract Despite a burgeoning literature on malingering, clinicians have few assessment tools for the accurate classification of those persons feigning cognitive and neuropsychological deficits. We examine problems inherent in the validation of these assessment measures. We identify and discuss six potential strategies for the detection of feigned neuropsychological deficits: (a) floor effect, (b) symptom validity testing (SVT), (c) performance curve, (d) magnitude of error, (e) atypical presentation, and (f) psychological sequelae. In light of the available research, we critically review specific methods which incorporate these strategies. We found that Rey's 15-Item Memory Test, as a measure of floor effect, had very low sensitivity rates. We also found considerable variability in SVT methods; a computerized version of SVT (Pritchard & Moses, 1991) that measured auditory, visual, and memory abilities had a satisfactory sensitivity of 67%. Overall, strategies that employed performance curves appeared to have the greatest promise in identifying potential malingerers. The remaining three detection strategies have not been adequately tested .
Apoptosis Signaling in Tumor Therapy

Apoptosis, the cell's intrinsic program to death, plays a central role in physiological growth control and regulation of tissue homeostasis. Tipping the balance between cell death and proliferation in favor of cell survival may result in tumor formation. Also, killing of cancer cells by cytotoxic therapies currently used for treatment of cancer, for example, chemotherapy, gamma-irradiation, immunotherapy, or suicide gene therapy, largely depends on activation of apoptosis programs in cancer cells. Accordingly, failure to undergo apoptosis in response to anticancer therapy may result in cancer resistance. Further insights into the mechanisms regulating apoptosis in response to anticancer therapy and how cancer cells evade cell death may provide novel opportunities for drug development.
On the Existence of the Halocarbonyl and Trifluoromethyl Cations in the Condensed Phase

Experimental and theoretical studies show that neither CF3+ nor FCO+ can be stabilized in the condensed phase with presently known Lewis acids. In the case of ClCO+, stabilization with SbF6- was also not possible, but Sb3F15 possesses sufficient acidity to abstract a fluoride ion from ClFCO in the formation of ClCO+Sb3F16-. This salt was fully characterized, providing the first well-established proof for the existence of a halocarbonyl cation in the condensed phase. Theoretical calculations and thermochemical cycles were used to corroborate our experimental findings, demonstrating that is possible to predict correctly whether a molecule with three different donor sites, such as ClFCO, will form an oxygen-coordinated donor−acceptor adduct or undergo either F- or Cl- abstraction. Furthermore, a method is described for extending natural bond orbital (NBO) analyses to systems containing two different types of competing, p(π) back-donating ligands.
An exact test for testing the equality of parameter matrices in two multivariate linear models

Abstract A method of testing the hypothesis of the kind H 0 : C ′ Φ 1 M = C ′ Φ 2 M in two independent multivariate linear models is presented using the concept of generalized p-values introduced by Tsui and Weerahandi [K.W. Tsui, S. Weerahandi, Generalized p-values in significance testing of hypothesis in the presence of nuisance parameters, J. Amer. Statist. Assoc. 84 (1989) 602–607] under the assumption of error matrix variate normality and heteroscedasticity. This method calculates the exact p-value in the generalized sense. Nel [D.G. Nel, Tests for equality of parameter matrices in two multivariate linear models, J. Multivariate Anal. 61 (1997) 29– 37] provided an approximate degrees of freedom test to test this hypothesis.
Smart search agents for image/graphics-based educational databases

In this p aper, a smart a gent is proposed to search image/graphics b ased database for students and an instructor. The search procedure is based on content-based image retrieval (CBIR). In addition, the smart agent can also gives help in searching image/graphics data, answering simple questions, and optimizing educational activities graphically.
Claiming a moral minority, saccades help create a biased majority: Tracking eye movements to base rates in social predictions

Abstract How do people hold erroneous views about their own moral behavior? This study investigated the use of distributional information in self and social predictions by measuring eye movements to base rates. Across 15 scenarios, participants claimed moral superiority over a comparison peer by predicting that base rates would be less predictive of one’s own behaviors than a comparison peer’s. In support of the differential use of distributional information hypothesis, participants looked less often to base rate information when making self rather than social predictions. Eye movements mediated the relationship between target of the prediction and the strength of the relationship between base rates and behavioral likelihood estimates. Implications for self-deception in self and social judgment are discussed.
Relative Acidities of Ortho-Substituted Phenols, as Models for Modified Tyrosines in Proteins

The effects of a variety of ortho-substituents (CH3, OH, OCH3, SH, SCH3, NH2, NO2, F, Cl, CN, and imidazole) on the acidity of phenol are investigated using hybrid density functional theory. Substi ...
Notable new North and Central American records of Ephemeroptera species

ABSTRACT New regional distribution records and range extensions involving one Canadian province, 17 Mexican states, 10 USA states, and five Central American countries are given for 53 species of Ephemeroptera. In Mexico, states with the greatest number of new species records include Queretaro, Mexico, Nueva Leon and Tamaulipas. For the USA, states with the greatest number of new species records include Oklahoma, Wisconsin, Kentucky and Texas. Farrodes flavipennis, Lachlania fusca and Leptohyphes peterseni records are the first for Mexico and North America, and the presence of Tricoryhyphes mulaiki in Texas represents a new USA record. New Central American country records include Americabaetis pleturus in El Salvador, Camelobaetidius arriaga and Thraulodes zonalis in Guatemala, Euthyplocia hecuba in Honduras, and Thraulodes pacaya in Costa Rica. Highly disjunct northern range extensions discovered for Tricorythodes robacki and T. albilineatus in the St. Croix River on the Minnesota/Wisconsin border paralle...
Adaptation of tobacco hornworms to the ingestion of nicotine

Abstract Radiometric, chromatographic, and spectrophotometric data show excretion and egestion of intact nicotine to be an explantion for the adaptation of the tobacco hornworm, Protoparce sexta (Johan.), to tobacco. There was no evidence for the metabolism of nicotine to less toxic metabolites after topical, injected, or ingested doses. Although nicotine was absorbed into the blood of the hornworm, a toxic dose did not appear to accumulate at the site of action.
Input variable identification—fuzzy curves and fuzzy surfaces

Abstract When modeling a complex, poorly defined, nonlinear problem with hundreds of possible inputs, we must identify the significant inputs before any known nonlinear modeling techniques can be applied. In this paper the concept of fuzzy surfaces is introduced and used to automatically and quickly identify a subset of independent significant inputs for use in nonlinear system models.
Numerical stability analysis of nonlinear Schrödinger equation via congruence transformation

Abstract In this paper, we present a congruence transformation for studying the numerical stability condition of the nonlinear Shrodinger equation i u t + u x x + p u + q | u | 2 u = 0 , i 2 = − 1 , subject to homogeneous Neumann boundary conditions, where p and q are real parameters. The congruence transformation takes advantage of a special structure of the matrices that result from Galerkin’s discretization with piecewise linear functions and product approximation for the nonlinear term by decoupling the system of perturbation into independent subsystems. This transformation can also be applied to solving any linear system T x = b if T is of the same special structure.
Routine Evaluation of the Distal Colon Remnant Before Hartmann’s Reversal is Not Necessary in Asymptomatic Patients

Background Reversal of Hartmann’s is a common surgical procedure. Routine preoperative evaluation of the distal colonic/rectal remnant (DCRR) with contrast and/or endoscopic studies is frequently performed despite lack of evidence to support this practice. We hypothesize that asymptomatic patients can safely undergo Hartmann’s reversal without preoperative DCRR evaluation.
Regulation of Luteinizing Hormone Secretion in Male Sheep by Endogenous Estrogen

Both androgens and estrogens are implicated in the regulation of gonadotropin secretion in the male. Three experiments were conducted to determine the physiological importance of estradiol (E2) in the feedback regulation of LH secretion in male sheep. In the first experiment, LH secretion in castrate rams (wethers) was shown to be susceptible to the picomolar concentrations of E2 found in intact rams. In the second experiment, aminoglutethimide (AG) was administered to testosterone-implanted wethers to block aromatization of testosterone and ascertain the possible consequences of E2 deprivation on testosterone-mediated LH suppression. AG had no apparent effect on serum testosterone, but reduced serum E2 by half and increased serum LH approximately 3-fold. These data suggest that aromatization of testosterone to E2 is a physiologically important step in the regulation of LH secretion in the ram and that aromatization occurs, at least in part, in peripheral tissues. The relative contributions of peripherall...
In Front of Your Nose

Interoperability in the Grocery Store The spirit of this column is to take what we can from our everyday experiences, events, places, and services—in other words, experiences that are right in fron...
Optimizing Power Transfer Efficiency and Bandwidth for Near Field Communication Systems

Near-field communication (NFC) is a specification for short-range wireless links operating at 13.56 MHz in the high-frequency (HF) band. The achievable bandwidth, efficiency, and range of lightweight, size-constrained, low-power NFC systems are limited by fundamental theorems of small antenna theory. We develop a relationship between near field power transfer and radiation efficiency for dipole-type antennas, which is applicable to both communications and wireless power transfer applications, and present modeled and experimentally measured results for the bandwidth efficiency product of two ferrite loop antenna designs. The model is used to determine the optimal geometrical parameters that maximize this figure of merit for a given antenna size. Modeled and measured results show that ferrite loops can approach theoretical limits on performance for the bandwidth efficiency product of an antenna with a given size.
Domestic credit and the balance of payments in Ghana

This model strives to assess the relationship between domestic credit and the balance of payments in Ghana during the 1961—75 period in an effort to guide policymakers in generating credit policies aimed at reaching a particular balance of payments objective. An equation is derived and estimated which specifies the relationship between domestic credit, exports, capital flows, and net foreign assets within a constraint imposing balance of payments equilibrium. The general conclusions of the analysis are that excessive increases in domestic credit were the principal cause for the balance of payments deficits incurred by Ghana during the period considered.
Hydrogenation of electron traps in bulk GaAs and GaP

The effect of hydrogenation on a variety of electrically active defects in bulk single-crystal GaAs and GaP has been observed using transient capacitance spectroscopy. Approximately half the different defect states in these materials were neutralised by hydrogen incorporation. The efficiency of neutralisation was slightly more pronounced for defects in GaAs compared to those in GaP.
Gender differences, clinical correlates, and longitudinal outcome of bipolar disorder with comorbid migraine

Objective Migraine is a common comorbidity of bipolar disorder and is more prevalent in women than men. We hypothesized comorbid migraine would be associated with features of illness and psychosocial risk factors that would differ by gender and impact outcome. Method A retrospective analysis was conducted to assess association between self-reported, physician-diagnosed migraine, clinical variables of interest, and mood outcome in subjects with DSM-IV bipolar disorder (N = 412) and healthy controls (N = 157) from the Prechter Longitudinal Study of Bipolar Disorder, 2005-2010. Informed consent was obtained from all participants. Results Migraine was more common in subjects with bipolar disorder (31%) than in healthy controls (6%) and had elevated risk in bipolar disorder women compared to men (OR = 3.5; 95% CI, 2.1-5.8). In men, migraine was associated with bipolar II disorder (OR = 9.9; 95% CI, 2.3-41.9) and mixed symptoms (OR = 3.5; 95% CI, 1.0-11.9). In comparison to absence of migraine, presence of migraine was associated with an earlier age at onset of bipolar disorder by 2 years, more severe depression (β = .13, P = .03), and more frequent depression longitudinally (β = .13, P = .03). Migraine was correlated with childhood emotional abuse (P = .01), sexual abuse (P = 4 × 10⁻³), emotional neglect (P = .01), and high neuroticism (P = 2 × 10⁻³). Protective factors included high extraversion (P = .02) and high family adaptability at the trend level (P = .08). Conclusions Migraine is a common comorbidity with bipolar disorder and may impact long-term outcome of bipolar disorder, particularly depression. Clinicians should be alert for migraine comorbidity in women and in men with bipolar II disorder. Effective treatment of migraine may impact mood outcome in bipolar disorder as well as headache outcome. Joint pathophysiologic mechanisms between migraine and bipolar disorder may be important pathways for future study of treatments for both disorders.
Radiation Therapy and Mechanical Dilation of Endobronchial Obstruction Secondary to Wegener's Granulomatosis

A patient with Wegener's granulomatosis, which was otherwise well controlled with steroids and cyclophosphamide, had persistent total obstruction of an inflamed left mainstem bronchus. The inflammation resolved, and the lung expanded following radiation therapy. However, intermittent atelectasis and pneumonia occurred distal to a residual short stricture. Repeated dilation endoscopically with Plummer bougies has proven effective in maintaining good ventilation and preventing recurrence of the atelectasis and pneumonia in the left lung for 18 months.
Sulfur isotopic analysis of 3–10 micromole samples of SO2 from sulfides, sulfates, and whole rocks using conventional combustion and mass spectrometric techniques

Abstract Both the CuO [Grinenko, V.A., 1962. The preparation of sulphur dioxide for isotope analysis. Zn. Neorgan. Khim. 7, 2478–2483; Fritz, P., Drimmie, R.J., Nowicki, V.K., 1974. Preparation of sulfur dioxide for mass spectrometer analyses by combustion of sulfides with copper oxide. Analytical Chemistry, 46, 164–166.] and V2O5–SiO2 [Yanagisawa, F., Sakai, H., 1983. Thermal decomposition of barium sulfate–vanadium pentaoxide–silica glass mixtures for preparation of sulfur dioxide in sulfur isotope ratio measurements. Analytical Chemistry, 55, 985–987; Ueda, A., Krouse, H.R., 1986. Direct conversion of sulphide and sulphate minerals to SO2 for isotope analyses. Geochemical Journal, 20, 209–212.] methods of `off-line' SO2 production from sulfide and sulfate minerals for sulfur isotope measurements are shown to be suitable for samples containing as little as 3 μmoles of S. δ 34 S values relative to a laboratory standard fall within ±0.1‰ for samples larger than 10 μmoles, and ±0.4‰ (maximum observed value) for smaller samples. Preheating of reagents, particularly native Cu that is used to reduce SO3 to SO2, is necessary for sulfide samples that produce less than ∼10 μmoles SO2. The pretreatment reduces blank effects and potential contaminant interferences. The CuO–Cu method is also suitable for combustion of whole rock samples containing as little as 150 ppm S. δ 34 S reproducibilities are not as good as for mineral separates, but are within ±0.5‰ for samples that contain between 170 and 350 ppm S.
Dynastic parties: Organization, finance and impact

In the aftermath of the 2009 national elections in India a number of commentators observed that Indian party politics is a dynastic affair. Why is this the case? This paper claims that absence of a...
Diamond and diamond-like carbon from a preceramic polymer

The synthesis of poly(hydridocarbyne), one of a class of carbon-based random network polymers and a structural isomer of polyacetlyene, is reported. The network backbone of this polymer is primarily composed of tetrahedrally hybridized carbon atoms, each bearing one hydride substituent and linked via three carbon-carbon single bonds into a three-dimensional random network of fused rings. This atomic-level carbon network backbone confers unusual properties on the polymer, including facile thermal decomposition to form diamond or diamond-like carbon high-quality films at atmospheric pressure, by direct deposition or by chemical vapor deposition (CVD), without the use of hydrogen or any other reagent.
New Evidence of the Interdependence in the Labor-Supply Behavior of White Couples

A logit technique is used to estimate couples' joint probabilities of various labor-force statuses, given their personal characteristics. Conditional probabilities of the labor-force status of spouses are inferred. An analysis of these probabilities suggests that, while spouses appear to be complementary in participation decisions, there is also evidence of substitutability in spouses' work hours, ceteris paribus.
Deletion, Methylation, and Expression of the NKX3.1 Suppressor Gene in Primary Human Prostate Cancer

NKX3.1 is a prostate-specific homeoprotein and tumor suppressor that is affected by the loss of 8p21 in prostate cancer. In mice, Nkx3.1 haploinsufficiency results in prostatic dysplasia and complements cancer formation induced by loss of other suppressor genes. However, NKX3.1 expression can be immunohistochemically detected in most primary prostate cancers. We examined the relationship between suppressor gene haploinsufficiency, methylation, and quantitative NKX3.1 expression levels in primary prostate cancer. NKX3.1 gene copy number was assessed by microsatellite analysis, fluorescence in situ hybridization, and quantitative PCR. NKX3.1 gene methylation was determined in prostate cancer cell lines and we thereby identified potential CpG methylation sites for methylation-specific PCR analysis in tissues. We validated and then applied an internally controlled fluorescence immunomicroscopic assay for NKX3.1 protein expression in 48 primary prostate cancer specimens from radical prostatectomies. NKX3.1 loss of heterozygosity was found in 27 of 43 tissues tested. Classic CpG island methylation of the NKX3.1 gene was not found in either prostate cancer cell lines or tissues. However, in 33 of 40 samples tested, CpG sites at -921, -903, and -47 were methylated to a greater degree in malignant than in adjacent normal cells. In 43 of 48 samples, NKX3.1 protein expression was reduced from 0.34 to 0.90 compared with adjacent normal luminal epithelium (mean of all samples, 0.68; 95% confidence interval, 0.05). In 12 cases that also had high-grade prostatic intraepithelial neoplasia, NKX3.1 expression levels were similar in preinvasive and invasive cancer cells and significantly lower than adjacent normal cells. Even in the presence of allelic loss, NKX3.1 expression is reduced over a wide range in prostate cancer at the time of prostatectomy, suggesting that diverse factors influence expression. Samples with protein expression below the median level in cancer cells had both NKX3.1 deletion and selective CpG methylation.
Silicon Insertion into Boranes: A Rational Synthetic Route to Silicon-Containing Heteroboranes.

The reactive dianion nido-B10H122- has been shown to insert silicon moieties to generate heteroundecaboranes of the form 7-R-7-SiB10H12-. NMR data for two new derivatives (R = H, Ph) are presented in addition to a proposed mechanism of insertion.
SEASONAL CHANGES IN THE THYROID AND INTERRENAL GLANDS OF THE TROPICAL AUSTRALIAN SKINK, LEIOLOPISMA RHOMBOIDALIS.

Abstract Seasonal variation in the thyroid and interrenal glands of the lizard Leiolopisma rhomboidalis was noted over a period of 12 months. Material was collected in the tropical region of north-eastern Australia. Least seasonal variation was noted in the thyroid and interrenal glands of the nongravid females. Gravid females exhibited greater variation than nongravid females and less than the males in both endocrine organs studied. The cold season (May–August) was the period of least activity of both thyroid and interrenal glands. Greatest thyroid activity in the males occurred during the hot, dry season (September–December). Greatest interrenal activity of the males occurred during the hot, wet season (January–April). Thyroid activity seems related to reproductive activity-yolk maintenance in the females, and copulation and territory defense in the males. Interrenal activity also, to a lesser degree, appears related to reproduction in this lizard. Without experimental work it is impossible at present to establish more positive interrelationships between thyroid and interrenal gland activity.
Pretreatment of sunflower stalks for biogas production

Sunflower stalks were subjected to commercial-scale pretreatment by hot-water maceration and steam-explosion technology to enhance biogas production. The technology involved does not require heavy construction nor does it consume any additional energy, chemicals, or rare catalysts. Process parameters regarding the mass flow, operating temperature, retention times, hydromodule, pressure, micropore area, formation of inhibitors, and especially the methane yields were plotted in detail to allow further optimization of the design. It was found that the optimal settings should come from both the macerator and steam-explosion subunits because various synergistic effects may be achieved.
Caching for bursts (C-Burst): let hard disks sleep well and work energetically

High energy consumption has become a critical challenge in all kinds of computer systems. Hardware-supported Dynamic Power Management (DPM) provides a mechanism to save disk energy by transitioning an idle disk to a low-power mode. However, the achievable disk energy saving is mainly dependent on the pattern of I/O requests received at the disk. In particular, for a given number of requests, a bursty disk access pattern serves as a foundation for energy optimization. Aggressive prefetching has been used to increase disk access burstiness and extend disk idle intervals, while caching, a critical component in buffer cache management, has not been paid a specific attention. In the absence of cooperation from caching, the attempt to create bursty disk accesses would often be disturbed due to improper replacement decision made by energy unaware caching policies. In this paper, we present the design of a set of comprehensive energy-aware caching schemes, called C-Burst, and its implementation in Linux kernel 2.6.21. Our caching schemes leverage the 'filtering' effect of buffer cache to effectively reshape the disk access stream to a bursty pattern for energy saving. The experiments under various scenarios show that C-Burst schemes can achieve up to 35% disk energy saving with minimal performance loss.
Reappraisal of endosonography of ampullary tumors: correlation with transabdominal sonography, CT, and MRI.

Purpose. To reappraise the accuracy of transabdominal sonography (US), CT, MRI, and endosonography (EUS) in the diagnosis and staging of ampullary tumors. Method. We reviewed the medical records and the images of 41 consecutive patients with ampullary tumors. Tumor detection rate and accuracy of TNM (tumor–node–metastasis) staging of malignant tumors were determined. Imaging findings were correlated with histopathologic findings. Results. The detection rates for ampullary tumors were 97.6% for EUS, 81.3% for MRI, 28.6% for CT, and 12.2% for US (p 0.05 for EUS versus MRI). The accuracy in T staging for ampullary carcinomas was 72.7% for EUS, 53.8% for MRI, and 26.1% for CT (p 0.05 for EUS versus MRI). The accuracy in N staging for ampullary carcinomas was 66.7% for EUS, 76.9% for MRI, and 43.5% for CT with no statistically significant difference between the 3 modalities. The sensitivity in detecting malignant lymph nodes was 46.7% for EUS, 25.0% for MRI, and 0% for CT (p 0.05 for EUS versus MRI; p > 0.05 for MRI versus CT). Transpapillary stenting, advanced tumor extension (>T2), large tumor size (>2 cm), tumor differentiation, and endoscopic appearance of tumor growth did not significantly influence EUS accuracy in T or N staging (p > 0.05). Conclusion. EUS was superior to CT and was equivalent to MRI for tumor detection and T and N staging of ampullary tumors. Neither indwelling stents nor tumor size, differentiation, or endoscopic appearance affected the staging accuracy of EUS. © 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2009
Dynamic Motion Generation for Redundant Systems Under External Constraints

Dynamics of mechanical systems during motion usually involves reaction forces and moments due to the interaction with external objects or constraints from the environment. The problem of predicting the external reaction loads under rigid-body assumption has not been addressed extensively in the literature in terms of optimal motion planning and simulation. In this presentation, we propose a formulation of determining the external reaction loads for redundant systems motion planning. For dynamic equilibrium, the resultant reaction loads that include the effects of inertia, gravity, and general applied loads, are distributed to each contact points. Unknown reactions are determined along with the system configuration at each time step using iterative nonlinear optimization algorithm. The required actuator torques as well as the motion trajectories are obtained while satisfying given constraints. The formulation is applied to several example motions of multi-rigid-body systems such as a simple 3-degree-of-freedom welding manipulator and a highly articulated whole-body human mechanism. The example results are compared with the cases where the reactions are pre-assigned. The proposed formulation demonstrates realistic distribution of external reaction loads and the associated goal-oriented motions that are dynamically consistent.Copyright © 2010 by ASME
The Absence of Insulin Signaling in the Heart Induces Abnormalities in Ventricular Repolarization

Diabetes mellitus is associated with cardiac arrhythmias, ventricular fibrillation and sudden death. These cardiac effects may result directly from the absence of insulin signaling in the heart or as in indirect consequence of diabetic sequelae (e.g., hyperlipidemia, hypertension or coronary artery disease). To study the electrical consequences of absent insulin signaling in the heart, we used a cardiac-specific insulin receptor knock-out (CIRKO) mouse model. We recorded action potentials and K+ currents in myocytes isolated from CIRKO mice and their control littermates. Action potential duration at 90% (APD90) was significantly prolonged in left ventricle, apex and septum from CIRKO mice compared to WT. Conversely, no differences in APD90 were observed in right ventricular myocytes. Outward potassium currents recorded using whole-cell voltage clamp method showed a reduction in both peak and sustained current in CIRKO mice. Neither the voltage dependence of steady-state inactivation nor recovery from inactivation of the rapidly inactivating outward K+ current (Ito,f) were affected. In addition, the inward rectifier K+ current (IK1) was not different between both groups. Consistent with the APD prolongation, CIRKO mice showed QT interval prolongation, compared to WT littermates. Western blot and real time q-PCR analyses revealed that the protein levels and mRNA expression of Kv4.2 were significantly reduced in CIRKO hearts. We conclude that the absence of insulin signaling in the heart causes a reduction in Kv4.2 message and protein that in turn, reduces Ito,f, prolongs APD in left ventricle and prolongs the QT interval.
Novel post-synthetic generation, isomeric resolution, and characterization of Fapy-dG within oligodeoxynucleotides: differential anomeric impacts on DNA duplex properties

Accumulation of damaged guanine nucleobases within genomic DNA, including the imidazole ring opened N 6 -(2-Deoxy-a,b-D-erythro-pentafuranosyl)2,6-diamino-4-hydroxy-5-formylamidopyrimidine (Fapy-dG), is associated with progression of agerelated diseases and cancer. To evaluate the impact of this mutagenic lesion on DNA structure and energetics, we have developed a novel synthetic strategy to incorporate cognate Fapy-dG site-specifically within any oligodeoxynucleotide sequence. The scheme involves the synthesis of an oligonucleotide precursor containing a 5-nitropyrimidine moiety at the desired lesion site via standard solid-phase procedures. Following deprotection and isolation, the Fapy-dG lesion is generated by catalytic hydrogenation and subsequent formylation. NMR assignment of the Fapy-dG lesion (X) embedded within a TXT trimer reveals the presence of rotameric and anomeric species. The latter have been characterized by synthesizing the tridecamer oligodeoxynucleotide d(GCGTACXC ATGCG) harboring Fapy-dG as the central residue and developing a protocol to resolve the isomeric components. Hybridization of the chromatographically isolated fractions with their complementary d(CGCATGCGTACGC) counterpart yields two FapydG · C duplexes that are differentially destabilized relative to the canonical G · C parent. The resultant duplexes exhibit distinct thermal and thermodynamic profiles that are characteristic of a- and b-anomers, the former more destabilizing than the latter. These anomer-specific impacts are discussed in terms of differential repair enzyme recognition, processing and translesion synthesis.
Dallas Peck selected for USGS

Volcanologist Dallas Peck has been chosen by the Reagan administration to be the next director of the United States Geological Survey (USGS). Peck, chief geologist of the USGS since 1977, is a past president of AGU's section on Volcanology, Geochemistry and Petrology. If the Senate approves Reagan's choice, Peck will become the 11th director of the USGS, succeeding H. William Menard, who resigned in January. Doyle G. Frederick, associate director, has been serving as acting director. Dallas Peck is highly regarded throughout the Survey. His field studies include notable work in the Cascades of western Oregon, in the Sierra Nevada batholith, and at the Lava Lakes in Hawaii. He has been involved with geological projects in Alaska as well as with numerous studies in the U.S. related to geothermal and volcanic energy sources.
Prices, costs, and competition at the technology frontier: A model for semiconductor memories☆

Abstract Economic competition, both internationally and within national borders, is being profoundly affected by relative ability to participate in markets with short product cycles and significant learning periods. However, effective tools for examining policies in this context have yet to be developed. This paper attempts a first step by presenting an empirical model for the semiconductor memory industry. As an illustration, the model is used to analyze recent developments in the competition between U.S. and Japanese producers.
The shorted turn in the linear actuator of a high performance disk drive

The shorted turn in the linear actuator is analyzed using a transformer circuit model. Formulas are developed to calculate the transient response of the coil current in terms of the geometry. Results obtained by modeling compare favorably with experimentally obtained results.
A Simple Performance-Based Index for Assessing Multiple Agroecosystem Functions

Evaluating the impact agricultural practices have on agroecosystem functions is essential to determine the sustainability of management systems. This paper presents an approach to determine the relative sustainability of agricultural practices. A simple ranking procedure using a relative scoring method is proposed to discriminate among treatments based on the status of crop and soil parameters within different agroecosystem functions. Summing scores across agroecosystem functions allows for the identification of agricultural practices that are performing optimally based on functions included in the procedure. An example, using data from a long-term cropping systems experiment in the western Corn Belt, found the indexing procedure to successfully discern differences in overall performance across four agroecosystem functions between conventional [continuous corn (Zea mays L.) cropping sequence at a fertilization rate of 180 kg N ha -1 ] and alternative [corn-oat (Avena sativa L.) + clover (Trifolium pratense L.)-grain sorghum [Sorghum bicolor (L.) Moench]-soybean [Glycine max (L.) Merr.] cropping sequence at a fertilization rate of 90 kg N ha 1 } management systems. The simplicity, inclusiveness, and inherent flexibility of the indexing procedure can be considered benefits and drawbacks, depending on the point of view taken. Data requirements of the approach, however, are stringent. Consequently, its most appropriate use may be with data from long-term agroecosystem experiments.
Agents of Change: Pathways through which Mentoring Relationships Influence Adolescents' Academic Adjustment.

A conceptual model was tested in which the effects of mentoring relationships on adolescents' academic outcomes were hypothesized to be mediated partially through improvements in parental relationships. The parameters of the model were compared with those of an alternative, in which improved parental relationships were treated as an outcome variable rather than a mediator. The study included 959 young adolescents (M age = 12.25 years), all of whom applied to Big Brothers Big Sisters programs. The adolescents were randomly assigned to either the treatment or control group and administered questions at baseline and 18 months later. The hypothesized model provided a significantly better explanation of the data than the alternative. In addition to improvements in parental relationships, mentoring led to reductions in unexcused absences and improvements in perceived scholastic competence. Direct effects of mentoring on global self-worth, school value, and grades were not detected but were instead mediated through improved parental relationships and scholastic competence. Implications of the findings for theory and research are discussed.
Promoting Mexican Immigrant Families' Weil-Being: Learning from Parents What is Needed to Have a Strong Family:

This study explored factors that Mexican immigrant parents deem necessary to promote the well-being of their families. Mexican immigrant parents participated in focus groups following the passage of SB1070 in Arizona. Findings revealed four interrelated constructs that parents aim for to strengthen their families: family norms and practices; transmitting Latino culture; work and education; and goals and motivation. Participants' responses broaden and contextualize our understanding of Mexican immigrants' family norms. In light of anti-immigrant policies and sentiment, participants stressed maintaining/transmitting their culture, including the Spanish language, to promote their children's ethnic identity development; they also stated that parents' internal drive is crucial to promoting their families' well-being. Opportunities to ground interventions on Mexican family strengths are discussed.
Controlled-flying proximity sliders for head-media spacing variation suppression in ultralow flying air bearings

As the slider's flying height (FH) continues to be reduced in hard disk drives, the flying height modulation (FHM) due to disk morphology and interface instability caused by highly nonlinear attractive forces becomes significant. Based on the concept that the FH of a portion of the slider that carries the read/write element can be adjusted by a piezoelectric actuator located between the slider and suspension and that the FH can be measured by use of the magnetic readback signal, a new 3-degree of freedom analytic model and an observer-based nonlinear compensator are designed to achieve ultralow FH with minimum modulation under short range attractive forces. Numerical simulations show that the FHM due to disk waviness is effectively controlled and reduced.
How and to what extent are free radicals involved in the nonoxidative thermal dehydrochlorination of poly(vinyl chloride)

Kinetic analyses based on the resonance delocalization energies of polyenes and polyenyl radicals are used to rule out the free-radical mechanisms of Arlman and of Winkler and Stromberg for the growth of conjugated polyenes during the thermolysis of poly(vinyl chloride) under nonoxidizing conditions. Possible sources of radicals during the thermolysis are described, and the radicals that cause the greatest reduction in thermal stability are identified as those that result from the reaction of polyenes with HCl. The way in which these radicals accelerate dehydrochlorination is discussed. J. VINYL ADDIT. TECHNOL., 2012. © 2012 Society of Plastics Engineers
Testing the Role of Adolescent Sexual Initiation in Later-Life Sexual Risk Behavior A Longitudinal Twin Design

The consistent association between adolescent sexual initiation (ASI) and risky adult sexual behavior (RASB) has generally been assumed to indicate that ASI has a causal effect on RASB; consequently, it is assumed that delaying ASI will reduce RASB. Yet the ASI-RASB association might be better accounted for by some third variable. We evaluated the causal role of ASI (initiation of oral, anal, or vaginal sex at or before age 16) in influencing RASB in a longitudinal sample of 2,173 twins (followed from ages 11 to 24 or from ages 17 to 29) using two methods: the discordant-twin design and the propensity-score design. The former controlled for unmeasured genetic and shared environmental factors, and the latter controlled for measured nonshared environmental factors. We replicated the link between ASI and RASB reported in previous research, but results from the discordant-twin and propensity-score analyses suggested that this association is better explained by common genetic or environmental risk factors than as a causal effect. These findings suggest that preventing ASI is unlikely to reduce RASB.
Measurement and real-time cancellation of vibration-induced phase noise in a cavity-stabilized laser

We demonstrate a method to measure and actively reduce the coupling of vibrations to the phase noise of a cavity-stabilized laser. This method uses the vibration noise of the laboratory environment rather than active drive to perturb the optical cavity. The laser phase noise is measured via a beat note with a second unperturbed ultra-stable laser while the vibrations are measured by accelerometers positioned around the cavity. A Wiener filter algorithm extracts the frequency and direction dependence of the cavity response function. Once the cavity response function is known, real-time noise cancellation can be implemented by use of the accelerometer measurements to predict and then cancel the laser phase fluctuations. We present real-time noise cancellation that results in a 25 dB reduction of the laser phase noise power spectral density.
Transfer learning algorithms for image classification

An ideal image classifier should be able to exploit complex high dimensional feature representations even when only a few labeled examples are available for training. To achieve this goal we develop transfer learning algorithms that: (1) Leverage unlabeled data annotated with meta-data; and (2) Exploit labeled data from related categories. In the first part of this thesis we show how to use the structure learning framework (Ando and Zhang, 2005) to learn efficient image representations from unlabeled images annotated with meta-data. In the second part we present a joint sparsity transfer algorithm for image classification. Our algorithm is based on the observation that related categories might be learnable using only a small subset of shared relevant features. To find these features we propose to train classifiers jointly with a shared regularization penalty that minimizes the total number of features involved in the approximation. To solve the joint sparse approximation problem we develop an optimization algorithm whose time and memory complexity is O( n log n) with n being the number of parameters of the joint model. We conduct experiments on news-topic and keyword prediction image classification tasks. We test our method in two settings: a transfer learning and multitask learning setting and show that in both cases leveraging knowledge from related categories can improve performance when training data per category is scarce. Furthermore, our results demonstrate that our model can successfully recover jointly sparse solutions. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)
Sketcha: a captcha based on line drawings of 3D models

This paper introduces a captcha based on upright orientation of line drawings rendered from 3D models. The models are selected from a large database, and images are rendered from random viewpoints, affording many different drawings from a single 3D model. The captcha presents the user with a set of images, and the user must choose an upright orientation for each image. This task generally requires understanding of the semantic content of the image, which is believed to be difficult for automatic algorithms. We describe a process called covert filtering whereby the image database can be continually refreshed with drawings that are known to have a high success rate for humans, by inserting randomly into the captcha new images to be evaluated. Our analysis shows that covert filtering can ensure that captchas are likely to be solvable by humans while deterring attackers who wish to learn a portion of the database. We performed several user studies that evaluate how effectively people can solve the captcha. Comparing these results to an attack based on machine learning, we find that humans possess a substantial performance advantage over computers.
A new universal random coding bound for the multiple-access channel

The minimum average error probability achievable by block codes on the two-user multiple-access channel is investigated. A new exponential upper bound is found which can be achieved universally for all discrete memoryless multiple-access channels with given input and output alphabets. It is shown that the exponent of this bound is greater than or equal to those of previously known bounds. Moreover, examples are given where the new exponent is strictly larger.