cssi/SciSciGPT-SciSciNet huggingface dataset:
Computer utilization in engineering mechanics education

Abstract For the last 20 years, the Mechanics Division of the American Society for Engineering Education has surveyed engineering schools to ascertain trends in mechanics education. Every five years an extensive instrument is sent to over 200 engineering schools. This year, for the first time, a series of questions dealing with computer utilization was included. This paper will report results of computer related items only. The timing of the reported results is critical, since the advent of moderately priced computers is fairly recent and no coherent plans for computer use in mechanics have been formulated.
Maintenance of testosterone status in fitness joggers after increased training mileage.

The primary objective was to evaluate the early effect of increased training mileage on testosterone (T) status in recreational joggers. Serum total (Ttot) and free (Tfree) concentrations at rest, overnight urinary Ttot excretion, and the Ttot and Tfree responses to maximal exercise were used as indicators of T status. A group of 13 male [mean (SD) age 24.5 (2.5) years] fitness joggers [maximal oxygen consumption, $$ \dot V{\rm O}_{{\rm 2max}} $$ , 52.9 (4.9) ml·kg–1·min–1] qualified as subjects. The training intervention consisted of a 100% increase in the habitual distance run [12 (3) miles·week–1] for 2 consecutive weeks, while maintaining the customary training intensity. Blood samples were obtained at rest and after maximal exercise tests, at the beginning and end of a control week of habitual jogging (baseline) and also following the 1st and 2nd weeks of the intervention. The $$ \dot V{\rm O}_{{\rm 2max}} $$ and treadmill exercise endurance time were unchanged across sampling times. Serum Ttot and Tfree concentrations averaged 565 (62) and 24 (2.6) ng·dl–1, respectively, at baseline and did not change significantly. Urinary Ttot excretion averaged 1.5 (0.21) ng·min–1 at baseline, and also remained unchanged during the intervention. Relative increases in Ttot (23%) and Tfree (22%) were observed following maximal exercise compared to rest (P<0.05). However, the exercise-related increases in serum Ttot and Tfree were not evident after adjustment for the change in plasma volume. It was concluded, that the training intervention did not alter T status in these fitness joggers.
Low-Pressure Sorption-Enhanced Hydrogen Production

The sorption-enhanced production of hydrogen involves the simultaneous steam−methane reforming, water−gas shift, and CO2 removal reactions in the presence of a reforming catalyst and CO2 sorbent. High concentrations of H2 with low concentrations of CO are produced in a single reaction step. Pure CO2 suitable for use or sequestration may be produced during sorbent regeneration. This study examined the sorption-enhanced H2 production reactions at low pressure, which also requires a low reaction temperature so that the sorbent will retain its effectiveness for CO2 capture. H2 concentrations in excess of 96 mol % (dry basis) and CO concentrations as low as 7 ppmv (dry basis) were produced in tests between 1 and 5 bar and 400 and 460 °C using a H2O-to-CH4 feed ratio of 3. Calcined Arctic SHB dolomite proved to be an effective CO2 sorbent that did not require pretreatment for sulfur removal.
A complete backbone spectral assignment of lipid-free human apolipoprotein E (apoE)

Apolipoprotein E is an exchangeable apolipoprotein that plays an important role in lipid/lipoprotein metabolism and cardiovascular diseases. Recent evidence indicates that apoE is also critical in several other important biological processes, including Alzheimer’s disease, cognitive function, immunoregulation, cell signaling and infectious diseases. Although the X-ray crystal structure of the apoE N-terminal domain was solved in 1991, there is no structure available for the apoE C-terminal domain and full-length apoE. Here we report a complete NMR backbone spectral assignment of lipid-free human apoE.
Development of a steel component combustion model for fires involving pure oxygen systems

Pure oxygen systems pose significant fire and explosion risk to equipment, operations, and personnel if a loss of oxygen containment occurs. In industrial oxygen systems, combustion of metal can be initiated by a variety of ignition sources. The combustion of process vessel walls, components, or piping can result in loss of containment of pressurized oxygen. Automatic shutdown and isolation systems are designed to detect loss of containment, incipient loss of containment due to process parameters (e.g., pressure drop), or internal fire conditions. The effectiveness of these isolation systems is dependent upon the speed with which they activate after the initiating event. The prediction of failure modes and time scales can be an important tool in the design, operation, and maintenance of industrial high purity oxygen systems. Modeling of metal consumption in oxygen fueled fires requires consideration of multiple ignition mechanisms. Previously published experimentation has been motivated by the need to compare the relative burn resistance of metals and nonmetals under a variety of operating conditions, but has not produced a tool to inform the potential for loss of containment in oxygen systems based on the different ignition mechanism failure modes. This work aims to develop a series of theoretical models using experimental results and kinetic relationships in order to predict loss of containment in piping for industrial systems for combinations of different failure modes. Using this type of analysis, process designers can make informed decisions on the design of high purity oxygen systems, the timescale required by emergency shutdown systems, and schedules for routine maintenance and inspection. © 2014 American Institute of Chemical Engineers Process Saf Prog 33: 299–304, 2014
Decisionmaking by Third Parties in Settling Disputes1

This study concerns decisionmaking by men who serve as third parties in disputes between two other individuals. A study was made of hearings at which a government official (O) attempted to judge the merits of a wage claim brought by a worker (C) against his former employer (D). O's attitudes before and after the hearing were assessed, and a content analysis was made of a script of the hearing process. O was the most active participant in the interaction. O developed more attitudinal structure about the case than he had had initially, and showed an increase in the degree of his evaluative differentiation between the contending parties. Unexpectedly, the consistency of O's attitudes about each party decreased somewhat in cases where he announced a decision. A striking pattern of evidence occurred concerning the special relation that usually developed between O and the “loser” of the case (the party less preferred by O at the end.) He reacted more negatively to the loser than he did positively to the winner. It was suggested that a postdecision contention between O and the loser was triggered by O's revelation of his judgment and that the subsequent interchange resulted in O's having a clear and negative view of the loser at the conclusion of the hearing.
On the nature of the companion to Van Biesbroeck 8

Results of the first numerical evolutionary calculations for very low-mass stars with ages up to the age of the Galaxy are presented. The calculations shed new light on the nature of the recently discovered object VB 8B, the companion to Van Biesbroeck's star no. 8, and support the identification of this object as a low-mass star in which hydrogen burning was never able to establish thermal equilibrium. For plausible ages of this binary stellar system, the mass of VB 8B is estimated to be in the range 0.04-0.08 solar mass. The object is supported primarily by degenerate electron pressure; its present values of central density and temperature are found to be 500-2000 g/cu cm and 1.0-1.5 million K. An orbital period of more than about 40 yr is predicted for the binary system. The presented evolutionary tracks are also applicable to the interpretation of observations of other very low-luminosity dwarfs.
Quantum interference of tunnel trajectories between states of different spin length in a dimeric molecular nanomagnet

An experimental study of a ‘dimeric’ single-molecule magnet—consisting of two coupled half-wheels of spin 7/2 each—provides evidence for quantum interference between the two sub-systems. Tunable electron spins in solid media are among the most promising candidates for qubits1. In this context, molecular nanomagnets have been proposed as hardware for quantum computation2. The flexibility in their synthesis represents a distinct advantage over other spin systems, enabling the systematic production of samples with desirable properties, for example, with a view to implementing quantum logic gates3,4. Here, we report the observation of quantum interference associated with tunnelling trajectories between states of different total spin length in a dimeric molecular nanomagnet. We argue that the interference is a consequence of the unique characteristics of a molecular Mn12 wheel, which behaves as a molecular dimer with weak ferromagnetic exchange coupling: each half of the molecule acts as a single-molecule magnet, whereas the weak coupling between the two halves gives rise to an extra internal spin degree of freedom within the molecule—that is, its total spin may fluctuate. More importantly, the observation of quantum interference provides clear evidence for quantum-mechanical superpositions involving entangled states shared between both halves of the wheel.
The ex vivo isolated skeletal microvessel preparation for investigation of vascular reactivity.

The isolated microvessel preparation is an ex vivo preparation that allows for examination of the different contributions of factors that control vessel diameter, and thus, perfusion resistance1-5. This is a classic experimental preparation that was, in large measure, initially described by Uchida et al.15 several decades ago. This initial description provided the basis for the techniques that was extensively modified and enhanced, primarily in the laboratory of Dr. Brian Duling at the University of Virginia6-8, and we present a current approach in the following pages. This preparation will specifically refer to the gracilis arteriole in a rat as the microvessel of choice, but the basic preparation can readily be applied to vessels isolated from nearly any other tissue or organ across species9-13. Mechanical (i.e., dimensional) changes in the isolated microvessels can easily be evaluated in response to a broad array of physiological (e.g., hypoxia, intravascular pressure, or shear) or pharmacological challenges, and can provide insight into mechanistic elements comprising integrated responses in an intact, although ex vivo, tissue. The significance of this method is that it allows for facile manipulation of the influences on the integrated regulation of microvessel diameter, while also allowing for the control of many of the contributions from other sources, including intravascular pressure (myogenic), autonomic innervation, hemodynamic (e.g., shear stress), endothelial dependent or independent stimuli, hormonal, and parenchymal influences, to provide a partial list. Under appropriate experimental conditions and with appropriate goals, this can serve as an advantage over in vivo or in situ tissue/organ preparations, which do not readily allow for the facile control of broader systemic variables. The major limitation of this preparation is essentially the consequence of its strengths. By definition, the behavior of these vessels is being studied under conditions where many of the most significant contributors to the regulation of vascular resistance have been removed, including neural, humoral, metabolic, etc. As such, the investigator is cautioned to avoid over-interpretation and extrapolation of the data that are collected utilizing this preparation. The other significant area of concern with regard to this preparation is that it can be very easy to damage cellular components such as the endothelial lining or the vascular smooth muscle, such that variable source of error can be introduced. It is strongly recommended that the individual investigator utilize appropriate measurements to ensure the quality of the preparation, both at the initiation of the experiment and periodically throughout the course of a protocol.
Mosquito Saliva Serine Protease Enhances Dissemination of Dengue Virus into the Mammalian Host

Dengue virus (DENV), a flavivirus of global importance, is transmitted to humans by mosquitoes. In this study, we developed in vitro and in vivo models of saliva-mediated enhancement of DENV infectivity. Serine protease activity in Aedes aegypti saliva augmented virus infectivity in vitro by proteolyzing extracellular matrix proteins, thereby increasing viral attachment to heparan sulfate proteoglycans and inducing cell migration. A serine protease inhibitor reduced saliva-mediated enhancement of DENV in vitro and in vivo, marked by a 100-fold reduction in DENV load in murine lymph nodes. A saliva-mediated infectivity enhancement screen of fractionated salivary gland extracts identified serine protease CLIPA3 as a putative cofactor, and short interfering RNA knockdown of CLIPA3 in mosquitoes demonstrated its role in influencing DENV infectivity. Molecules in mosquito saliva that facilitate viral infectivity in the vertebrate host provide novel targets that may aid in the prevention of disease.
Single Photon Emission Computerized Tomography With Capromab Pendetide Plus Computerized Tomography Image Set Co-Registration Independently Predicts Biochemical Failure

Purpose: We evaluate the usefulness of pretreatment 111Indium capromab pendetide (ProstaScint™) planar imaging (immunoscintigraphy) plus single photon emission tomography co-registration with computerized tomography scans to detect occult metastatic disease and predict for biochemical failure, in a cohort of patients with a clinical diagnosis of localized adenocarcinoma of the prostate referred for primary radiotherapy.Materials and Methods: Patients were followed after radiotherapy for evidence of biochemical failure using 2 criteria of prostate specific antigen clinical nadir +2 ng/ml and American Society for Therapeutic Radiology and Oncology Consensus definitions. Median followup was 58.8 months (mean 64.8). Clinical risk factors defined 3 risk groups of high (51), intermediate (72) and low (116).Results: Overall biochemical failure was 18.3% vs 11.8% by the 2-BFC at 8-year actuarial analysis with 58.8 months median followup. By the CN +2 definition the control date for the cohort is 34.8 months. Pret...
Sentence-order feedback during processing of sequential or spatial texts

This study is a continuation of work on the effects of feedback on text processing. Subjects reconstructed scrambled versions of two qualitatively similar texts. One version was based on the sequential order of locations encountered on a drive through a town (route); the other described the same place in geographical terms (survey). The results confirmed previous research, which showed the following: (1) Readers can develop a surface memorial representation of the text without further processing; (2) readers can recall significant amounts of fragmented ideas; and (3) feedback seems to differentially assist recall rather than recognition of original text. The implications for instructional assistance are discussed.
Phase diagrams of binary mixtures of biaxial nematogens

Abstract A mean field theory is used to describe nematic phases of binary mixtures of biaxial molecules. Using a general pseudopotential consistent with the D2h symmetry of the constituent particles, the theory is used to calculate the elements of the order tensors necessary to describe the orientational order in binary mixtures in both uniaxial and biaxial nematic phases. For a single component, the model only requires one parameter, r 2, a ratio of anisotropic interaction strengths, to predict the temperature dependence of the four order parameters. The temperature dependence of the orientational distribution functions is illustrated for both rod-like and plate-like molecules. For binary mixtures, three anisotropic interaction strengths, r 1, r 2, and r 3, are needed to calculate the order parameters of both components as a function of concentration and temperature. The free energy is evaluated to predict the phase stability of the mixture. By systematically varying the anisotropic interaction strengths...
Optimal Control of Hidden Markov Models With Binary Observations

A hidden Markov model (HMM) consisting of a controlled Markov chain and a binary output is considered. The binary output reports the occurrence of a certain state (versus any other state) in the Markov chain. The transition matrix of the Markov chain depends on a control vector which is to be chosen to minimize a discounted infinite-horizon cost function. The information provided for decision making is the entire history of the binary output which presents an incomplete knowledge of the Markov chain and, as a consequence, leads to a stochastic control problem with partial observations. The solution to such a problem is a control policy consisting of two components: an estimator to derive the posterior probability distribution of the Markov chain from the observation set, and a nonlinear control law to map this estimate into the control vector. This paper introduces a nonlinear state-space representation for the estimator, develops analytical expressions for the control law, and presents numerical methods for efficient computation of the optimal control. Application of these results to optimal management of a class of inventory systems is discussed, and the performance of optimal control for this application is examined by numerical simulations.
Treatment of Graves' disease: The American way

The treatment of patients with Graves' disease involves a physician making a clinical decision between one of the three modalities available for treatment, administering the treatment and following the patients. There appears to be a difference in treatment bias for treating the 'average' patient with Graves' disease, with American physicians preferring radioactive iodine while their European and Japanese cohorts prefer long-term anti-thyroid drugs. There are no facts to support this bias. The treating physician usually makes the decision based on his or her preference. In addition, American physicians are under pressure to prescribe the most cost-effective therapy, leading to an even stronger bias towards radioactive iodine.
Populations, prey capture and sharing, and foraging of the Paraguayan Ponerine Odontomachus chelifer Latreille.

Summary In central Paraguay, the ponerine ant Odontomachus chelifer is found in densities of less than one colony/ha in mixed woodland, and is almost always associated with Atta sexdens, the dominant leaf-cutting ant. Individual colony populations number less than 150. Foraging was found to be highly seasonal, and to be preceded by the formation of preforage aggregations. With increasing colony hunger, foraging activity increased. Moreover, definite preferences were shown for certain common termite prey species. With increasing colony hunger, less food was shared among workers.
Predicting the Quality of One-Dimensional Periodic Micro and Nano Structures Fabricated via Wrinkling

Wrinkling of thin films due to buckling-based surface instabilities is a fast and inexpensive technique for template-free fabrication of periodic micro/nano scale structures. Although one-dimensional (1-D) periodic micro and nano structures have been fabricated via wrinkling in the past, wrinkling is not yet appropriate for a manufacturing environment. This is because it is currently not possible to predict and control the quality of the fabricated patterns. Pattern quality is quantified in terms of the uniformity of the pattern, i.e., defect density within the patterned area. Herein, we (i) identify the process parameters that affect pattern quality, (ii) model the effect of these parameters on wrinkling quality and (iii) quantify the feasible operating region for a target pattern quality. During wrinkling, dislocation defects are observed due to local geometric imperfections such as voids or variations in the material properties. We have developed a finite element model of the wrinkling process that accounts for voids in the material. The wavelength and amplitude predictions of this model were found to be within ∼13% of the experimental observations. Also, it was found that below a threshold void size, the non-uniformity in the pattern due to voids decays with an increase in the applied compressive strain. This provides a practical means to minimize the non-uniformity in 1-D wrinkled patterns by increasing the compression. However, the defect density due to surface cracks increases with an increase in the compressive strains. Our analysis enables one to identify and predict the feasible operating region within which uniform 1-D patterns can be obtained, thereby improving manufacturability via wrinkling.Copyright © 2012 by ASME
Can new objects override attentional control settings

Previous research suggests that attentional capture by abrupt onsets is contingent on top-down attentional control settings. Four experiments addressed whether similar contingencies hold for capture elicited by the appearance of new perceptual objects. In a modified spatial cuing task, targets defined by abrupt onset or color were paired with distractors consisting of an abrupt brightening of an existing object or the abrupt appearance of a new object. In Experiments 1 and 2, when subjects searched for an onset target, both distractor types produced evidence of capture. When subjects searched for a color target, however, distractors produced no evidence of attentional capture, regardless of whether they consisted of a new perceptual object or not. Experiments 3-5 showed that the lack of distractor effects in the color-target condition cannot be accounted for by rapid recovery from capture. It was concluded that attentional capture by new objects is subject to top-down modulation by attentional control settings.
Benign retroperitoneal neural sheath tumors in patients without von Recklinghausen's disease

Benign retroperitoneal neural sheath tumors in patients without von Recklinghausen's disease are quite rare and usually presented as isolated case reports. There are two types of benign neural sheath neoplasms: schwannoma and neurofibroma. Confusion exists in the nomenclature of these tumors due to the disagreement upon their cell of origin. In a collective report from two institutions, three cases with benign retroperitoneal neural sheath tumors are presented, and the histological features, diagnostic and therapeutic options are discussed.
Lessons learned in getting your board to initiate change

The article reports on a study by Jerry Goodstein of Washington State University, Kanak Gautman of St. Louis University, and Warren Boeker of Columbia University, which focused on the corporate board's role in initiating change. The researchers examined strategic change at hospitals in California in relation to their boards' size and diversity. They found a correlation between board size and the timely reorganization of services. Smaller boards reorganized more services than the larger boards. Board size did not impact the addition or elimination of services.
A Novel Anterograde Trafficking Signal Present in the N-terminal Extracellular Domain of Ionotropic Glutamate Receptors

Abstract Trafficking of α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptors to and from the postsynaptic membrane plays an important role in regulating transmission at excitatory synapses. AMPA receptor subunits contain a large extracellular N-terminal domain that is important for receptor assembly (1). To further investigate the determinants of receptor assembly and surface expression, we have epitope-tagged the N-terminal domain of the AMPA receptor subunit, GluR1, and expressed it in human embryonic kidney 293 cells and hippocampal neurons. Full-length GluR1 was readily detected on the cell surface in both cell types. However, surface expression was profoundly decreased by deletion or replacement of nine amino acids in the extreme N terminus. Immunoprecipitation experiments demonstrated that the mutant GluR1 in which this sequence was deleted still interacts with GluR2, suggesting that mutant GluR1 is capable of at least partial assembly into heteromeric structures. The mutant forms of GluR1 co-localize with an endoplasmic reticulum marker suggesting that they are retained in this structure. These results suggest a specific function of a short sequence present in the N-terminal domain in controlling anterograde trafficking of ionotropic glutamate receptors.
Preliminary Evidence Regarding the Validity of the Personal Orientation Inventory as a Measure of the Construct Self-Actualization

This study was designed to compare scores on a pretest—the Personal Orientation Inventory (POI) (Shostrom, 1974)—taken immediately after a stressful experience (as inferred from measures on a polygraph) with scores on the posttest taken two weeks after the removal of the stressful condition. In this exploratory construct validity study the central objective was to ascertain whether hypothesized changes in the mean scores on the subscales of the POI would occur to a statistically significant degree in directions reflecting a higher degree of self-actualization after elimination of the stressful condition and after verbal reassurance of one's perceptual capabilities. The twenty-one subjects were randomly selected from one hundred-seventy graduate students enrolled in a school counseling-training program. Significant differences in the predicted direction were found on two of the twelve subscales, Self Regard and Self Acceptance on the POI.
Comparison of two Caenorhabditis genes encoding FMRFamide(Phe-Met-Arg-Phe-NH2)-like peptides

Abstract We have identified a gene encoding multiple FMRFamide-like peptides in the necromenic nematodeCaenorhabditis vulgaris. This gene,Cv-flp-1, shares strong sequence homology in the coding regions with theflp-1 gene from the related free-living soil nematodeC. elegans. The predicted neuropeptide precursor proteins differ by only four conservative amino acid changes, none of which affects sequences of the predicted neuropeptides. DNA sequences in the non-coding areas are less conserved, but areas of sequence homology are found in introns and in 3′ and 5′ non-translated regions, suggesting some functional significance for these conserved regions. InC. vulgaris, as was found inC. elegans, two transcripts are presumably produced as a result of use of an alternative 3′ splice acceptor site. Lastly, an antibody specific for the RF-moiety of FMRFamide stains a similar subset of cells inC. elegans andC. vulgaris. These results indicate that the function and regulation of the peptides are likely to be conserved in both species.
The effect of overtraining on reversal learning under conditions of no nonreinforcement

Groups of rats trained with 60 or 198 trials on a one vs. three pellet T-maze place discrimination task were subsequently taught the reverse of the task. During reversal the high incentive alternative contained nine pellets while the reward on the other side remained three pellets. The number of incorrect choices during reversal was directly related to amount of initial training. Significant increases and decreases in running speeds to the high and low incentive alternatives, respectively, were observed during reversal training.
A Simplified Dynamical System for Tropical Cyclone Intensity Prediction

Abstract A simplified dynamical system for tropical cyclone intensity prediction based on a logistic growth equation (LGE) is developed. The time tendency of the maximum sustained surface winds is proportional to the sum of two terms: a growth term and a term that limits the maximum wind to an upper bound. The maximum wind evolution over land is determined by an empirical inland wind decay formula. The LGE contains four free parameters, which are the time-dependent growth rate and maximum potential intensity (MPI), and two constants that determine how quickly the intensity relaxes toward the MPI. The MPI is estimated from an empirical formula as a function of sea surface temperature and storm translational speed. The adjoint of the LGE provides a method for finding the other three free parameters to make the predictions as close as possible to the National Hurricane Center best-track intensities. The growth rate is assumed to be a linear function of the vertical shear (S), a convective instability paramet...
Some New Error Bounds and Approximations for Pattern Recognition

For the average error probability Pe associated with the Bayes recognition procedures for two possible patterns, using no context, new upper and lower bounds and approximations are obtained. Results are given in terms of simple functions of feature "reliability" and a priori probabilities of the patterns. Two kinds of feature "reliability" are considered, i.e., distance between probability distributions and error probabilities without the use of a priori probabilities. Computational advantages offered by those bounds and approximations are pointed out. The question as to how close they are to P e is examined. In some special cases, they are perfect. Numerical examples show that the differences are in general about 5-10 percent, and comparisons with certain known results are quite favorable. Possible applications are discussed. Extension is also made to m possible patterns arranged in a hierarchy with two elements at each branching.
Reduced frontal white matter integrity in early-onset schizophrenia: a preliminary study.

Abstract Background Research suggests that brain frontal white matter (WM) might be qualitatively altered in adolescents with early onset schizophrenia (EOS). Diffusion tensor imaging provides a relatively new approach for quantifying possible connectivity of WM in vivo. Methods Diffusion tensor imaging was used to examine the WM integrity of frontal regions at seven levels from 25 mm above to 5 mm below the anterior commissure–posterior commissure (AC-PC) plane. Three other regions were examined: the occipital region at the AC-PC plane and the genu and splenium of the corpus callosum. Fractional anisotropy was compared between 12 adolescents (nine male, 3 female) with EOS (onset of psychotic symptoms by age 18 years) and nine age-similar healthy comparison subjects (six male, 3 female). Results Adolescents with EOS had significantly reduced fractional anisotropy in the frontal WM at the AC-PC plane in both hemispheres and in the occipital WM at the AC-PC plane in the right hemisphere. Conclusions These preliminary data support a hypothesis that alterations in brain WM integrity occur in adolescents with EOS. Abnormalities found in this study were similar to those reported in adults with chronic schizophrenia. Additional studies are needed to assess whether there is progression of WM abnormalities in schizophrenia.
Strong temperature dependence of ferromagnetism at Ni and Tb surface determined with electron capture spectroscopy ECS

Abstract The magnetic structure of the topmost atomic layer of Ni and Tb surface has been investigated using electron capture spectroscopy (ECS). Contrary to bulk behavior, at Ni(111) surfaces, the long-range magnetic order, characterized by the long-range electron spin polarization (ESP), decreases from −43% at T = 293 K almost linearly to zero at the bulk Curie temperature T cb = 631 K. The “local” surface magnetic order (SMO) at Ni(111) surfaces is temperature independent and is detected far above T cb . At Tb surfaces, however, the “local” SMO is strongly temperature dependent and disappears above T cb . ft]+|Walter-Meissner-Institute f. Low-Temp.-Res., Bav. Acad. Sci., D8046 Garching, F.R.G.
Spatial frequency tuning of human stereopsis

Abstract A masking paradigm was employed to measure the spatial frequency selectivity of channels underlying human stereopsis. Observers viewed spatially filtered (0.4 octave bandwith) random-dot stereograms in which a disparate bar appeared in either the top or bottom half of the display; superimposed on one RDS half-image was a noise target whose spatial frequency content was varied relative to that of the RDS. A staircase procedure was used to measure the monocular noise energy (and hence the signal-to-noise ratio) at which observers could judge the location of the disparate bar on 71% of trials. Statistical analyses showed that the resulting stereoscopic masking functions could be grouped into two sets, one with peak sensitivity at 3 c/deg and the other with peak sensitivity at 5 c/deg. These two channels were observed for both crossed and uncrossed disparities ranging from coarse to fine. Essentially the same results were obtained with binocular noise and with stereo displays flashed too briefly to be affected by eye movements. Our results are inconsistent with models of stereopsis in which the disparity range to which a channel is sensitive varies with that channel's peak spatial frequency. These data imply that the spatial frequency selectivity of stereopsis differs from the tuning of spatial channels underlying the detection and discrimination of form.
Affinity chromatography of lactic acid dehydrogenase on N-(6-aminohexyl)oxamate-sepharose.

Abstract A competitive inhibitor (Ki = 10−4–10−5 m ) for lactic acid dehydrogenase (LDH), N-(6-aminohexyl)oxamate, was synthesized from diethyl oxalate and 1,6-diaminohexane. The affinity column prepared by attachment of this compound to CNBr-activated Sepharose 4B enabled efficient purification of LDH from the marine teleost, Fundulus heteroclitus (Lin.). A similar affinity absorbent prepared by the method of O'Carra and Barry (FEBS Lett. (1972) 21, 281) gave a less satisfactory purification because the LDH was contaminated with phosphorylase a. The reason for this contamination was traced to an incomplete acylation of amino groups on the modified Sepharose beads by the carbodiimide-mediated reaction. Immobilization of the presynthesized affinant, N-(6-aminohexyl)oxamate, assured complete absence of these interfering groups. An alternate synthetic scheme, involving an active ester of ethyl oxalate, was also found to eliminate this problem.
μ -Mesonic Molecular Ions and Nuclear Catalysis

The experimental observation of the catalysis of nuclear reactions by mu mesons in liquid hydrogen created interest at a number of laboratories and led to several independent theoretical investigations of the processes involved. Some estimates of particular reaction rates were in wide disagreement, primarily because of the gross approximations made. In order to obtain a more satisfactory understanding of these processes, a detailed investigation has been made of the molecular systems involved in these reactions. In the investigations of the molecular ions the Born-Oppenheimer approximation is used. In this calculation, corrections to the first order in the ratio of mesonic to nucleonic mass were included. (A.C.)
Finding haplotype tagging SNPs by use of principal components analysis.

The immense volume and rapid growth of human genomic data, especially single nucleotide polymorphisms (SNPs), present special challenges for both biomedical researchers and automatic algorithms. One such challenge is to select an optimal subset of SNPs, commonly referred as “haplotype tagging SNPs” (htSNPs), to capture most of the haplotype diversity of each haplotype block or gene-specific region. This information-reduction process facilitates cost-effective genotyping and, subsequently, genotype-phenotype association studies. It also has implications for assessing the risk of identifying research subjects on the basis of SNP information deposited in public domain databases. We have investigated methods for selecting htSNPs by use of principal components analysis (PCA). These methods first identify eigenSNPs and then map them to actual SNPs. We evaluated two mapping strategies, greedy discard and varimax rotation, by assessing the ability of the selected htSNPs to reconstruct genotypes of non-htSNPs. We also compared these methods with two other htSNP finders, one of which is PCA based. We applied these methods to three experimental data sets and found that the PCA-based methods tend to select the smallest set of htSNPs to achieve a 90% reconstruction precision.
Monoclonal Antibody Characterization of the 1,4‐Dihydropyridine Receptor of Rabbit Skeletal Muscle

The 1,4-dihydropyridine receptor (DHPR) of the voltage-dependent Ca channel has been purified from transverse tubular membranes of skeletal muscle. Curtis and Catterall have shown that it consists of three polypeptides of 160,000 daltons, 50,000 Da, and 32,000 Da and that under reducing conditions the apparent molecular weight of the 160,000 Da subunit shifted to 130,000. Borsotto et al. have identified three polypeptides of 142,000 Da, 33,000 Da, and 32,000 Da in their preparation of the dihydropyridine receptor. Furthermore, they have shown by immunoblotting with polyclonal antibodies that the 142,000 Da and 32,000 Da subunits are produced by the reduction of a 170,000 Da polypeptide. We report here the identification and characterization with monoclonal antibodies (MAb) of an additional high molecular weight subunit of the DHPR which is distinct from that described by Curtis and Catterrall and Borsotto et al. Monoclonal antibodies capable of specifically immunoprecipitating the [H]PN200-110-labeled DHPR of rabbit skeletal muscle were produced by immunizing BALB/c mice initially with skeletal muscle triad vesicles followed by booster immunizations with purified DHPR from skeletal muscle triads. Hybridoma supernatants were screened for the production of anti-DHPR antibodies with an immunodot assay. Supernatants that reacted positively against the partially purified DHPR were then tested for their ability to immunoprecipitate the [H]PN200-110-labeled receptor from digitonin-solubilized triads (see TABLE 1). All three MAbs (IIC12, IIF7, IIID5) that were capable of immunoprecipitating the DHPR recognized a protein with an Mr of 170,000 on nitrocellulose transfers of skeletal muscle triads and transverse tubular membranes separated on sodium dodecyi sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) under nonreducing conditions (FIGURE la). Wheat-germ agglutinin (WGA) peroxidase stained a 175,000 Da protein on similar nitrocellulose transfers. Neither the 170,000 Da polypeptide nor the 175,000 Da polypeptide was detected in light sarcoplasmic reticulum vesicles, a preparation devoid of DHPR. Under reducing conditions, the Mr of the 170,000 Da
Energy Conversion in Cutting and Grinding

Abstract There are similarities and differences with regard to energy conversion in cutting and grinding. In both cases practically all of the energy ends up as heat. However, there are major differences in the dispersion of the heat in the two cases. There are two regimes of ginding depending on the undeformed chip size involved and each of these is associated with a different mode of chip formation. This paper discusses the conversion and transport of energy in cutting and grinding in fundamental terms.
Interlayering of Expansible Layer Silicates in Soils by Chemical Weathering

Interlayering of 2: 1 layer silicates varies as a function of chemical weathering from the simple, homogeneous K or Na interlayers of micas to the heterogeneous systems of mica intercalated with expanded 2: 1 layer silicates. “Frayed edge” type of weathering at dislocation planes of mica is collated with K release and preferential cation-exchange uptake of K relative to Ca by such expansible layer silicate systems; mica islands maintain alignment of the silica sheet cavities, which facilitates recapture of lattice K. Intercalation of the expanded 2: 1 layer silicates with alumina interlayers appears to be a characteristic function of chemical weathering in soils, with the formation of 2: 1–2: 2 intergrades not only of 14 A spacing but also of swelling 18 A types that give small 12, 14, 18 A and higher spacing peaks (along with the 10 A peak) at 550°C. Interlayer precipitates appear to be characteristic of soil clays, contrasting with “pure” minerals of deposits developed in less “open” environments than those of soils. The “2: 2 lattice building” phenomenon in expansible 2: 1 layer silicates relates to layer charge density and crystal size, and frequently tends to inhibit the formation of free gibbsite in soil chemical weathering so long as there are expansible layer silicates present to become intercalated with aluminum hydroxide—a weathering phenomenon that may be called an “antigibbsite effect”. Accumulation of alumina (possibly with some iron, magnesium, and allophane) as interlayers in 2: 1 minerals of soils is seen as a genetic stage in the 2: 2 → 1: 1 weathering sequence through which kaolinite and halloysite develop in soils.
The effect of single motherhood on smoking by socioeconomic status and race/ethnicity

Abstract We examined the association between parenting young children and smoking among US single women compared with married women, and whether this effect is moderated by socioeconomic status and race/ethnicity. Our main finding is that having children reduces smoking except among single white women, and women with low income. We used the Tobacco Use Supplement of the Current Population Survey, a nationally representative dataset (1995–96, n =70,019). Log-binomial regression analysis was used to estimate the association between parenting responsibility (i.e., presence of children aged 0–4 and 5–17) and daily smoking status, after taking into consideration marital status, income, and race/ethnicity. Single women faced a higher risk of smoking than married women. Parenting was protective against smoking among married women but not among single women. Additionally, among single women, the associations between parenting and smoking varied by income and race/ethnicity. Parenting increased the risk of smoking among single women in the lowest income quartile. Single black and Hispanic women with children had a risk of smoking similar to that of their childless counterparts. However, single white women with children were more likely to smoke than their childless counterparts. Smoking cessation interventions and programs to reduce environmental tobacco smoke should recognize that the co-occurrence of single motherhood, parenting responsibility and low-income may increase the risk of smoking. This is particularly significant given the rapid growth of the single women population, and their concentration in poverty in the USA. The finding that parenting is protective against smoking among single minority women, who presumably experience significant stressors, calls for a more thorough investigation of smoking behavior among minority women, and suggests the importance of stress buffers such as social support.
Patterns of Federal Urban Spending: Central Cities and their Suburbs, 1983-1992

A review of federal expenditures between 1983 and 1992 is presented in this study of per capita spending in central cities and their metropolitan suburbs. The Census Bureau provides data for 41 of the nation's metropolitan areas, of which 7 central cities are defined as county units of government and analyzed in greater detail. In constant dollars, central cities led suburbs in per capita receipt of federal funds; however, suburbs generally received an increase in their relative shares. In central cities, grants-in-aid increased but changed to entitlements directed to individuals.
Signal estimation using the discrete polynominal transform

The authors develop an iterative procedure for estimating the parameters of a signal consisting of multiple polynomial-phase components with time-varying amplitudes. The proposed algorithm is based on the discrete polynomial transform (DPT), and shares its computational simplicity. Preliminary experimentation with the algorithm has shown that it is able to provide accurate parameter estimates. A numerical example is included. >
INTEGRATING LOW-LEVEL FEATURES COMPUTATION WITH INDUCTIVE LEARNING TECHNIQUES FOR TEXTURE RECOGNITION

This paper presents a method for applying inductive learning techniques to texture description and recognition. Local features of texture are computed by two well-known methods, Laws’ masks and co-occurrence matrices. Then, a three-level generalization of local features is applied to create texture description rules. The first level generalization, the scaling interface, has been implemented to transform the numeric data of local texture features into their higher symbolic representation as numerical ranges. This scaling interface tests data consistency as well. The creation of description rules incorporating the inductive incremental learning algorithm is the second generalization step. The SG-TRUNC method of rule reduction is applied as the next hierarchical generalization level. This machine learning approach to texture description and recognition is compared with the classic pattern recognition methodology. The results from the recognition phase are presented from six classes of textures, characterized by smoothly changing illumination and/or texture resolution. The average recognition rate was 91% for the inductive learning approach, and all classes of textures were recognized. In comparison, the traditional k-NN pattern recognition method did not recognize one class of texture, and the average recognition rate was 83%. The proposed methodology smooths the recognition rates through the hierarchy of generalization levels, i.e. the next generalization step increases these rates for classes that were less easily recognized, and decreases these rates for classes that were more easily recognized.
KIF5B gene sequence variation and response of cardiac stroke volume to regular exercise.

A genome-wide linkage scan for endurance training-induced changes in stroke volume detected a quantitative trait locus on chromosome 10p11 in white families of the HERITAGE Family Study. Dense micr...
Understanding Albrecht's Model of Trade Cumulus Cloud Fields

Abstract Using Albrecht's model, approximate analytical formulas are found for the dependence of the steady-State mean thermodynamic structure of a partly cloudy convective marine boundary layer on external parameters. Our goals are 1) to understand the physical factors that influence the vertical profiles of mean relative humidity, temperature, and fractional cloudiness within the cloud layer using the model to gain insight into the strato-cumulus-trade cumulus transition in the subtropical trade wind regime, and 2) to understand the sensitivity of the model to tunable internal parameters. The model, a prototype for bulk models of trade cumulus boundary layer, consists of a well-mixed subcloud layer topped by a cumulus layer and a sharp trade inversion. In the simplest formulation discussed here, precipitation is ignored and simple parameterizations for radiative cooling and fractional cloudiness are used. The analytical approximation agrees well with exact steady-state numerical solutions of Albrecht's ...
Preferential technological and life cycle environmental performance of chitosan flocculation for harvesting of the green algae Neochloris oleoabundans.

Abstract Dewatering of the green algae Neochloris oleoabundans by flocculation was investigated for chitosan biopolymer, ferric sulfate, and alum. Chitosan was found to be most effective flocculant, with an optimum dose of 100 mg/L algae broth. Zeta potential measurements suggest the mechanism involves both adsorption and charge neutralization processes. Life cycle assessment (LCA) was used to compare the chitosan method to other flocculation methods as well as centrifugation and filtration/chamber press processes. LCA showed that among these techniques, flocculation by chitosan is the least energy intensive and had the lowest impacts across all other categories of environmental impacts. The results are discussed in the overall context of biofuel production from algal biomass.