cssi/SciSciGPT-SciSciNet huggingface dataset:
Disentangling prevalence induced biases in medical image decision-making

Abstract Many important real-world decision tasks involve the detection of rarely occurring targets (e.g., weapons in luggage, potentially cancerous abnormalities in radiographs). Over the past decade, it has been repeatedly demonstrated that extreme prevalence (both high and low) leads to an increase in errors. While this “prevalence effect” is well established, the cognitive and/or perceptual mechanisms responsible for it are not. One reason for this is that the most common tool for analyzing prevalence effects, Signal Detection Theory, cannot distinguish between different biases that might be present. Through an application to pathology image-based decision-making, we illustrate that an evidence accumulation modeling framework can be used to disentangle different types of biases. Importantly, our results show that prevalence influences both response expectancy and stimulus evaluation biases, with novices (students, N = 96) showing a more pronounced response expectancy bias and experts (medical laboratory professionals, N = 19) showing a more pronounced stimulus evaluation bias.
Empirically-informed guidelines for first-time adult ADHD diagnosis.

Introduction: Adult Attention Deficit/Hyperactivity Disorder (ADHD) is prone to misdiagnosis because its symptoms are subjective, share features with a broad range of mental, behavioral and physica...
Brain Imaging In Affective Disorders

General: brain imaging methods in neuropsychiatry investigation of mood disorders by transcranial magnetic stimulation. Anatomical studies: structural brain investigations in affective disorders brain anatomic circuits and the pathophysiology ofthe affective disorders. Functional and neurochemical brain studies: fMRI investigations in mood disorders MRS investigations and the pathophysiology of affective disorders. Psychopharmacology investigations: MRS as a tool for psychopharmacologicalstudies PET and SPECT imaging of antidepressant treatment effects in major depression. Summary and perspectives: differential brain mechanisms in bipolar and unipolar disorders - considerations from brain imaging brain imaging in affective disorders -current status and prospects for advances.
Corrigendum: The development of trunk control and its relation to reaching in infancy: a longitudinal study

Figure ​Figure44 of the article by Rachwani et al. (2015) contained a minor error, which we hereby rectify. In the original figure, the graph displaying the number of movement units across sitting development is incorrect (bottom graph on the left column). We therefore re-submit Figure ​Figure44 with the correct graph. We sincerely apologize for the inconvenience. Figure 4 Estimated means of group data across sitting developmental time. Y-axes display kinematic variables, X-axes display developmental time in months for thoracic (solid line with triangles) versus pelvic (dashed line with circles) support. Vertical dotted ...
Contrasting regional versus global radiative forcing by megacity pollution emissions

Abstract We assess the regional and global integrated radiative forcing on 20- and 100-year time horizons caused by a one-year pulse of present day pollution emissions from 10 megacity areas: Los Angeles, Mexico City, New York City, Sao Paulo, Lagos, Cairo, New Delhi, Beijing, Shanghai and Manila. The assessment includes well-mixed greenhouse gases: carbon dioxide (CO 2 ), nitrous oxide (N 2 O), methane (CH 4 ); and short-lived climate forcers: tropospheric ozone (O 3 ) and fine mode aerosol particles (sulfate, nitrate, black carbon, primary and secondary organic aerosol). All megacities contribute net global warming on both time horizons. Most of the 10 megacity areas exert a net negative effect on their own regional radiation budget that is 10–100 times larger in magnitude than their global radiative effects. Of the cities examined, Beijing, New Delhi, Shanghai and New York contribute most to global warming with values ranging from +0.03 to 0.05 Wm −2 yr on short timescales and +0.07–0.10 Wm −2 yr on long timescales. Regional net 20-year radiative effects are largest for Mexico City (−0.84 Wm −2 yr) and Beijing (−0.78 Wm −2 yr). Megacity reduction of non-CH 4 O 3 precursors to improve air quality offers zero co-benefits to global climate. Megacity reduction of aerosols to improve air quality offers co-benefits to the regional radiative budget but minimal or no co-benefits to global climate with the exception of black carbon reductions in a few cities, especially Beijing and New Delhi. Results suggest that air pollution and global climate change mitigation can be treated as separate environmental issues in policy at the megacity level with the exception of CH 4 action. Individual megacity reduction of CO 2 and CH 4 emissions can mitigate global warming and therefore offers climate safety improvements to the entire planet.
Using a boundary layer technique to reduce chatter in sliding mode controllers

A changing boundary layer width is used to adjust for the tradeoff between robustness and chatter elimination. Speed control of a DC motor is used as an example to demonstrate the effectiveness of the proposed approach. The boundary layer width is adjusted from a very large value (to eliminate chatter in the transient period) to a small value (to improve robustness as the system approaches steady state). A design model of the DC motor and a sliding mode controller using saturation type functions in place of the switching functions are developed. A discussion about the width of the boundary layer, chatter, robustness, and the effect of small time delays is presented. Performance with fixed boundary layer widths is simulated for various operating conditions in the motor speed example. A function of the state is then chosen to fit the gains, and response to the proposed controller is simulated. Comparisons to another boundary layer adjustment technique are drawn. >
Fixed rank kriging for very large spatial data sets

Summary. Spatial statistics for very large spatial data sets is challenging. The size of the data set, n, causes problems in computing optimal spatial predictors such as kriging, since its computa tional cost is of order A73. In addition, a large data set is often defined on a large spatial domain, so the spatial process of interest typically exhibits non-stationary behaviour over that domain. A flexible family of non-stationary covariance functions is defined by using a set of basis functions that is fixed in number, which leads to a spatial prediction method that we call fixed rank kriging. Specifically, fixed rank kriging is kriging within this class of non-stationary covariance functions. It relies on computational simplifications when n is very large, for obtaining the spatial best linear unbiased predictor and its mean-squared prediction error for a hidden spatial process. A method based on minimizing a weighted Frobenius norm yields best estimators of the covari ance function parameters, which are then substituted into the fixed rank kriging equations. The new methodology is applied to a very large data set of total column ozone data, observed over the entire globe, where n is of the order of hundreds of thousands.
Structure of the gene for human plasminogen activator inhibitor-2. The nearest mammalian homologue of chicken ovalbumin.

Abstract Plasminogen activator inhibitor-2 (PAI-2) can regulate the formation of plasmin by inhibiting urokinase and tissue plasminogen activator. PAI-2 is induced in monocytes and endothelium by inflammatory mediators, and it is made in the placenta during pregnancy. PAI-2 is a member of the serine protease inhibitor gene family, and it is particularly similar to chicken ovalbumin. Like ovalbumin, PAI-2 is secreted without cleavage of a signal peptide. To determine the structure of the PAI-2 gene, two bacteriophage lambda human genomic DNA libraries were screened with PAI-2 cDNA probes. Characterization of three positive clones shows that the human PAI-2 gene spans 16.5 kilobases and has eight exons. The 5'-untranslated sequence of the PAI-2 mRNA is 77 base pairs in length as suggested by primer extension and S1 nuclease mapping. The eukaryotic consensus sequence TATAAAA is found 22 base pairs 5' of the proposed cap site. The PAI-2 gene is on chromosome 18q21-23 as determined by hybridization to flow-sorted chromosomes and by in situ hybridization. There appear to be two common PAI-2 alleles that differ by six nucleotides in exons 1, 4, and 8. The structure of the PAI-2 gene is quite different from that of PAI-1 although these two inhibitors have common target protease specificity. In contrast, the structure of the PAI-2 gene is very similar to that of the chicken ovalbumin gene. When protein sequences are aligned to obtain maximal identity, six of the seven intron positions in the PAI-2 gene are identical to those in the chicken ovalbumin gene. We conclude that PAI-2 is the closest mammalian homologue of avian ovalbumin.
Face detection with information-based maximum discrimination

In this paper we present a visual learning technique that maximizes the discrimination between positive and negative examples in a training set. We demonstrate our technique in the context of face detection with complex background without color or motion information, which has proven to be a challenging problem. We use a family of discrete Markov processes to model the face and background patterns and estimate the probability models using the data statistics. Then, we convert the learning process into an optimization, selecting the Markov process that optimizes the information-based discrimination between the two classes. The detection process is carried out by computing the likelihood ratio using the probability model obtained from the learning procedure. We show that because of the discrete nature of these models, the detection process is at least two orders of magnitude less computationally expensive than neural network approaches. However, no improvement in terms of correct-answer/false-alarm tradeoff is achieved.
DENITRIFICATION BY CORYNEBACTERIUM NEPHRIDII.

Abstract Hart, Lewis T. (Louisiana State University, Baton Rouge), A. D. Larson, and C. S. McCleskey. Denitrification by Cornyebacterium nephridii. J. Bacteriol. 89:1104–1108. 1965.—Corynebacterium nephridii was found to reduce nitrate (contrary to the original description) at a rapid rate. In the conventional 0.1% nitrate broth, neither nitrite nor nitrate was detected after 24 hr. There was no assimilation of nitrate nitrogen, and the final product of nitrate reduction was nitrous oxide. Manometric studies and growth experiments indicated that the organism is incapable of reducing nitrous oxide. C. nephridii is gram-negative, grows on bile salts (5%) agar, EMB Agar, and MacConkey Agar. It was proposed that this species be transferrrd to the genus Achromobacter and designated Achromobacter nephridii (Busing, Doll, and Freytag) comb. nov.
Insights about adolescent behavior, plasticity, and policy from neuroscience research

Adolescent brain research has offered an explanation of adolescent behavior relevant for parents, society, and policymakers. As the science continues to evolve, it will advance understanding of adolescent potential and individual variation to further generate developmentally appropriate expectations, policies, and sanctions.
High-resolution sequence-based typing strategy for HLA-DQA1 using SSP-PCR and subsequent genotyping analysis with novel spreadsheet program.

We present a new sequence-based typing (SBT) strategy for the polymorphic HLA-DQA1 locus that is based on sequence-specific primer -polymerase chain reaction (SSP-PCR) amplification from genomic DNA. This method allows high-resolution genotyping in the second exon of the DQA1 gene. This gene presents a unique situation in which half of the known alleles contain an inframe three base pair deletion of codon 56. This deletion confounds direct SBT methodologies of heterozygous individuals containing both a deletion and nondeletion allele. The primary HLA haplotype associated with type 1 diabetes susceptibility is DR3/DR4. The DQA1 genotype for these two haplotypes are DQA1 * 0501, a non-deletion allele and * 0301, a deletion allele, thus creating a situation that cannot be resolved using a direct sequencing approach. Our group-specific SBT strategy isolates the deletion alleles from the nondeletion alleles, allowing them to be resolved by direct sequencing. Additionally, we present a novel spreadsheet program that accurately assigns the genotype of both homozygous and heterozygous persons.
Are wildlife films really “nature documentaries”?

(1998). Are wildlife films really “nature documentaries”? Critical Studies in Mass Communication: Vol. 15, No. 2, pp. 116-140.
Transport in branched systems II : transient response

Abstract Branched or fractal-like extended surfaces are commonly found in natural systems and are incorporated in engineered systems to enhance the rate of heat or mass transfer, or lo enhance the rate of chemical reaction. Many of these systems are required to respond to periodic inputs or to produce periodic outputs. Simple models can be derived to simulate the transport effectiveness and efficiency of these engineered structures and thereby provide some speculation concerning the evolutionary design and environmental control of natural branching systems The branched structures respond like classic, multi-pole, R-C low-pass filters whose cutoff frequencies and attenuations depend upon the extent of branching and the physical properties of the system. The low-pass filter response is advantageous because normal disturbances either in the external or internal environment are damped out before they are propagated and processed by the transmitter or the receiver. This is especially important in neural networ...
Interaction of tooth pulp and periodontal ligament receptors in a jaw-depression reflex.

Abstract Bipolar electrodes were implanted in the periodontal ligament space of the upper right and left canine teeth in eight cats to permit activation of periodontal ligament receptors, and in the predentin of each of these teeth, to permit activation of the pulpal nerves. Electrical stimulation of the periodontal ligament receptors of either canine tooth elicited a vigorous jaw-depression reflex. Tooth movement, which is known to stimulate the jaw-depression reflex, was completely avoided in this study. Summation of the sensory input from the two upper canine periodontal ligaments was demonstrated in every animal. In addition, summation was demonstrated between periodontal ligament receptors and tooth pulpal nerves.
Rifampin-induced deterioration in steroid-dependent asthma.

We encountered a patient with steroid-dependent asthma who had been stable while receiving 8 mg of methylprednisolone daily with a baseline FEV a of 65% of predicted value. He had a positive response to purified protein derivative (PPD), and administration of rifampln was started. Within a month, he required two emergency department visits for treatment of asthma. Despite substantial increases in the dose of methylprednisolone, his asthma continued to worsen. His FEV~ decreased to 40% of predicted value. Switching from methylprednisolone to prednisone also failed to improve his condition. However. the subsequent discontinuation of rifampin restored good control of his asthma. His FEV 1 returned to baseline.
Asteroid shapes from radar echo spectra: A new theoretical approach

Asteroid shape determinations are presently made by means of a novel technique based on the geometric relation between spectral edge frequencies and the shape of a rotating, rigid radar target. By employing the echo spectra obtained at many rotational phases, the asteroid's convex polar silhouette hull is obtained; noise content is treated as a problem in weighted-least-squares optimization, subject to inequality constraints. The performance of this estimation method is assessed in a series of simulated data giving attention to spectral noise propagation into hull error; sensitivity to echo strength and spectral resolution are also evaluated.
Optimization of algorithms for ion mobility calculations

Ion mobility spectrometry (IMS) is increasingly employed to probe the structures of gas-phase ions, particularly those of proteins and other biological macromolecules. This process involves comparing measured mobilities to those computed for potential geometries, which requires evaluation of orientationally averaged cross sections using some approximate treatment of ion-buffer gas collisions. Two common models are the projection approximation (PA) and exact hard-spheres scattering (EHSS) that represent ions as collections of hard spheres. Though calculations for large ions and/or conformer ensembles take significant time, no algorithmic optimization had been explored. Previous EHSS programs were dominated by ion rotation operations that allow orientational averaging. We have developed two new algorithms for PA and EHSS calculations: one simplifies those operations and greatly reduces their number, and the other disposes of them altogether by propagating trajectories from a random origin. The new algorithms were tested for a representative set of seven ion geometries including diverse sizes and shapes. While the best choice depends on the geometry in a nonobvious way, the difference between the two codes is generally modest. Both are much more efficient than the existing software, for example faster than the widely used Mobcal (implementing EHSS) approximately 10-30-fold.
Measurement of the Total Cross Section for Symmetric Charge Exchange in Helium from 400-2000 eV

The energy dependence of the total cross section for symmetric charge exchange in helium is measured in the range from 400-2000 eV. Beam-attenuation techniques are used, and all measurements are made on the forward-scattered ions and the high-energy neutrals resulting from the charge exchange. Cross-section values are given at 100-eV intervals, and the results show a cross section decreasing as the energy increases, with a value at 1000 eV of 1.04 \ifmmode\times\else\texttimes\fi{} ${10}^{\ensuremath{-}15}$ ${\mathrm{cm}}^{2}$. The absolute cross sections are accurate to \ifmmode\pm\else\textpm\fi{} 12%. Relative cross-section values accurate to \ifmmode\pm\else\textpm\fi{} 6% are reported.
An fMRI investigation of memory-related medial temporal lobe activation in mild cognitive impairment prior to dementia

sessed by single photon emission computed tomography (SPECT). Methods: A community sample of 1708 dementia-free individuals aged 65 years and over was examined by neuropsychological testing in an epidemiological survey. 117 subjects underwent magnetic resonance imaging (MRI) and SPECT with Tc-ethylcisteinate dimer. Subjects were classified into four groups (normal and 3 subclasses for MCI) based on the neuropsychological test. After an MRI-based correction for partial volume effect, differences in relative regional cerebral blood flow (rCBF) across groups were evaluated on a voxel-based basis using an analysis of covariance with age and education as covariates. Conclusions: Out of 117 subjects, 84 were classified as normal, 22 as having MCI-amnestic, 7 as MCI-single nonmemory domain, 4 as MCI-multiple domains slightly impaired, respectively. Subjects with MCI-amnestic showed significant relative rCBF reduction in the bilateral temporoparietal cortices, precuneus, cerebellum and right insula as compared with normal controls. Reduced rCBF were found for MCI-multiple domains slightly impaired in the bilateral anterior cingulate, superior and middle frontal gyrus, left temporoparietal cortex and right parahippocampal gyrus. For the MCI-single nonmemory domain, decreased rCBF were also shown in the bilateral temporoparietal regions and right parahippocampal gyrus. These results were thought to be consistent with the previous reports on MCI and early AD. Temporoparietal hypoperfusion were considered to be most common among subclassifications of MCI.
Shade and Traffic Tolerance Varies for Bermudagrass and Zoysiagrass Cultivars

Bermudagrass (Cynodon spp.) and zoysiagrass [Zoysia spp. (Willd.)] are two of the most commonly used turfgrass species in the southern United States. Shade from trees is common on golf courses and limits turfgrass growth. Additionally, turfgrasses used on golf courses and sports fields are often subjected to traffic. The objective of this study was to evaluate shade and traffic effects on bermudagrass and zoysiagrass. Two shade treatments were imposed, full sun or 49% shade, using a light reducing fabric. A Cady Traffic Simulator was used to implement traffic stress. The cultivars with the highest coverage in shade without traffic were 'Cavalier', 'Diamond', 'El Toro', 'Meyer', 'Palisades', and 'Zorro' zoysiagrass, as well as 'Princess 77' and 'Riviera' bermudagrass. 'Patriot', 'Tifsport', and 'Tifway' bermudagrass and 'Zenith' zoysiagrass typically had the lowest coverage. Patriot bermudagrass and Zenith zoysiagrass consistently had the lowest coverage in shaded trafficked plots. El Toro, Palisades, and Zorro zoysiagrass as well as Princess 77, Riviera, Tifsport, and Tifway bermudagrass had the highest coverage (>72%) when trafficked under full sun for 4 wk. Coverage in shaded plots was decreased more from traffic than full-sun plots. Riviera and Tifway bermudagrass had the most coverage after 6 wk of traffic in full sun. These studies identified cultivars of bermudagrass and zoysiagrass that perform better under reduced light and traffic stress.
The possible role of glia in nociceptive processing and hyperalgesia in the spinal cord of the rat.

Abstract Recent studies have suggested that glia might play a more active role in synaptic function than previously thought. Therefore, the present studies have evaluated the potential role of spinal cord glia in acute nociceptive processing and in the thermal and mechanical hyperalgesia produced by peripheral injury. In the present experiments, we found that: (1) selective inhibition of glia metabolism with intrathecal (i.t.) administration of fluorocitrate (1 nmol) results in a marked, but reversible, attenuation of the persistent thermal and mechanical hyperalgesia produced by intraplantar zymosan (5 mg); (2) selective inhibition of the inducible form of nitric oxide synthase (iNOS) with i.t. aminoguanidine (1 pmol-1 nmol) resulted in a dose-dependent inhibition of the persistent thermal, but not mechanical hyperalgesia produced by intraplantar zymosan (5 mg); (3) i.t. coadministration of interleukin 1β (IL1β; 10 ng) and interferon gamma (IFN; 1000 U) resulted in expression of the message for iNOS 8 hr after administration assessed using reverse-transcription polymerase chain reaction (RT-PCR) and Southern blot analysis; and (4) i.t. administration of lipopoly- saccharide (LPS; 150 μg) produced a time-dependent thermal hyperalgesia compared with saline treated-rats (15 μl). There was no change in mechanical withdrawal thresholds over time following any treatment, except fluorocitrate. We have previously shown that NO plays a significant role in mechanisms of hyperalgesia. In the present experiments we have extended these observations and have now shown a role for iNOS, expressed by glia, in mechanisms of hyperalgesia. These results suggest an unexplored avenue for the development of potential new and novel therapies for pain control.
Changes in the sorption capacity of Coastal Plain sediments due to redox alteration of mineral surfaces

Chemical characteristics of grain coatings in a Coastal Plain sandy aquifer on the Eastern Shore of Virginia were investigated where sediments have been exposed to distinct groundwater redox conditions. Dissolved O2 was 5.0 to 10.6 mg L−1 in the regionally extensive aerobic groundwater, whereas in a narrow leachate plume it was only <0.001 to 0.9 mg L−1. The amount of dissolved Fe in the aerobic groundwater was only 0.005 to 0.01 mg L−1, but it was 12 to 47 mg L−1 in the anaerobic zone. The amount of extractable Fe was an order of magnitude higher for the aerobic sediments than for the anaerobic sediments indicating that reductive dissolution removed the oxide coatings. The capacity for anion sorption on the sediment surfaces, as indicated by the sorption of 35SO42-, was an order of magnitude higher in the aerobic vs. anaerobic sediments. The presence of anaerobic groundwater did not significantly alter the amount of extractable Al oxides on the surface of the sediments, and those coatings helped to maintain a high surface area. The removal of the Fe oxides from the grain surfaces under anaerobic conditions was solely responsible for the significant reduction of SO4 sorption observed. This loss of capacity for anion sorption could lead to more extensive transport of negatively charged constituents such as some contaminant chemicals or bacteria that may be of concern in groundwater.
Evaluating the role of inbreeding depression in heterozygosity‐fitness correlations: how useful are tests for identity disequilibrium?

Heterozygosity-fitness correlations (HFCs) have been observed for several decades, but their causes are often elusive. Tests for identity disequilibrium (ID, correlated heterozygosity between loci) are commonly used to determine if inbreeding depression is a possible cause of HFCs. We used computer simulations to determine how often ID is detected when HFCs are caused by inbreeding depression. We also used ID in conjunction with HFCs to estimate the proportion of variation (r(2)) in fitness explained by the individual inbreeding coefficient (F). ID was not detected in a large proportion of populations with statistically significant HFCs (sample size = 120 individuals) unless the variance of F was high (σ(2)(F) ≥ 0.005) or many loci were used (100 microsatellites or 1000 SNPs). For example, with 25 microsatellites, ID was not detected in 49% of populations when HFCs were caused by six lethal equivalents and σ(2)(F) was typical of vertebrate populations (σ(2)(F) ≈ 0.002). Estimates of r(2) between survival and F based on ID and HFCs were imprecise unless ID was strong and highly statistically significant (P ≈ 0.01). These results suggest that failing to detect ID in HFC studies should not be taken as evidence that inbreeding depression is absent. The number of markers necessary to simultaneously detect HFC and ID depends strongly on σ(2)(F). Thus the mating system and demography of populations, which influence σ(2) (F), should be considered when designing HFC studies. ID should be used in conjunction with HFCs to estimate the correlation between fitness and F, because HFCs alone reveal little about the strength of inbreeding depression.
Verifying temporal properties without temporal logic

An approach to proving temporal properties of concurrent programs that does not use temporal logic as an inference system is presented. The approach is based on using Buchi automata to specify properties. To show that a program satisfies a given property, proof obligations are derived from the Buchi automata specifying that property. These obligations are discharged by devising suitable invariant assertions and variant functions for the program. The approach is shown to be sound and relatively complete. A mutual exclusion protocol illustrates its application.
Seminal fructose concentration as an index of androgenic activity in man.

THE prosecution of clinical research concerning metabolic and other physiologic properties of male hormone has been seriously handicapped by the lack of a specific sensitive index of either the rate of androgen secretion or the titer of circulating hormone. The measurement of various urinary excretory products which have been suggested for this purpose, has thus far been inadequate. The estimation of urinary 17-ketosteroids and the bio-assay of urinary androgens lack specificity as indicators of testicular androgen output since some of these steroids are derivatives of the adrenals as well as of the testes, and in addition their excretion may be influenced by factors other than glandular secretory activity (1). The excretion of urinary acid phosphatase, derived from the prostate gland, appear too variable from day to day to be useful (2). However, it was thought desirable to pursue the possibility that estimations of other secretory products of the accessory sex glands which require androgen for their dev...
Determination of phenylalanine hydroxylase activity by liquid chromatography/electrochemistry

An assay method is presented for the determination of phenylalanine hydroxylase activity in biological samples. The procedure is rapid and requires little sample. Multiple components of the enzyme system are determined and therefore serve as internal checks of the assay system. Liquid chromatography/electrochemistry is employed to follow the oxidation of the tetrahydropterin cofactor to the dihydropterin and to follow the formation of tyrosine. The KM and Vmax values of both phenylalanine and 6-methyl-5,6,7,8-tetrahydropterin were determined for mouse liver phenylalanine hydroxylase. Determination of the stoichiometry of the reaction showed that 1 mol of dihydropterin and 1 mol of tyrosine are formed per mole of tetrahydropterin that is oxidized. The reaction rate was linear for several minutes and over a wide range of enzyme (protein) concentrations.
Analyzing a Mathematics Lesson to Provide a Vehicle for Improving Teaching Practice.

A number of problems emerge when helping pre-service students with lesson planning, analysis of their lessons, and interpreting the lessons of others. Similar problems also arise when talking to practising teachers about mathematics lessons which involve them in new insights into teaching, new strategies and procedures. First, there are no universally accepted words, which describe key aspects of a mathematics lesson, that are able to stand alone without the need for extensive clarification and discussion. Second, there is no clear, generally accepted list for the parts or ‘properties’ that can make up a mathematics lesson. Third, there has been no detailed examination of mathematics lessons in terms of theories related to cognitive skill development. As a consequence of these three points: This paper addresses the above problems by It is further suggested that such an approach not only enables teachers to describe and clarify their current practices but that, given the teacher’s willingness to be better, such actions will result in the further development of teaching competencies at the level at which the teacher is currently working. This broadening of the knowledge base enables teachers to belter understand the lessons they plan, to be more innovative, less text book orientated and better able to generalize important aspects of ‘successful’ lessons into their teaching repertoire.
Tumor Progression in Ocular Melanomas

The term ocular melanoma refers to a heterogeneous group of cancers of melanocytic origin. The precursor of most cases of conjunctival melanoma is known to ophthalmologists as primary acquired melanosis. This condition passes through well-defined stages of tumor progression. Although tumor progression is not obligatory, as a conjunctival melanocytic lesion acquires new biologic properties it is more likely to progress further. Although junctional nevi are seldom encountered beyond childhood and primary acquired melanosis usually develops in middle-aged individuals, these two conditions may be histologically indistinguishable. Most junctional nevi eventually show evidence of differentiation, whereas nearly half of the cases of primary acquired melanosis with atypia progress to melanoma. Therefore, it is possible that aging may modulate the capability of certain clonal proliferations to differentiate. Uveal melanocytes normally reside in mesenchyme, so that the traditional histologic criterion for establishing the diagnosis of most melanomas – breach of an epithelial basement membrane – does not apply. Because uveal melanomas are not easily accessible to incisional biopsy (without disruption of vision), only two points in the spectrum of tumor progression are defined clinically: nevus and melanoma. Experimental evidence suggests that a spectrum of atypical melanocytic proliferations separates benign nevi from melanomas capable of generating metastases. Unlike conjunctival melanomas that spread first to regional lymph nodes, choroidal and ciliary body melanomas preferentially spread first to the liver and are examples of organ-specific metzstases.
The effect of speech rate on stuttering frequency, phonated intervals, speech effort, and speech naturalness during chorus reading.

Abstract Purpose This study examined the effect of speech rate on phonated intervals (PIs), in order to test whether a reduction in the frequency of short PIs is an important part of the fluency-inducing mechanism of chorus reading. The influence of speech rate on stuttering frequency, speaker-judged speech effort, and listener-judged naturalness was also examined. An added purpose was to determine if chorus reading could be further refined so as to provide a perceptual guide for gauging the level of physical effort exerted during speech production. Methods A repeated-measures design was used to compare data obtained during control reading conditions and during several chorus reading conditions produced at different speech rates. Participants included 8 persons who stutter (PWS) between the ages of 16 and 32 years. Results There were significant reductions in the frequency of short PIs from the habitual reading condition during slower chorus conditions, no change when speech rates were matched between habitual reading and chorus conditions, and an increase in the frequency of short PIs during chorus reading produced at a faster rate than the habitual condition. Speech rate did not have an effect on stuttering frequency during chorus reading. In general, speech effort ratings improved and naturalness ratings worsened as speech rate decreased. Conclusion These results provide evidence that (a) a reduction in the frequency of short PIs is not necessary for fluency improvement during chorus reading, and (b) speech rate may be altered to provide PWS with a more appropriate reference for how physically effortful normally fluent speech production should be. Future investigations should examine the necessity of changes in the activation of neural regions during chorus reading, the possibility of defining individualized units on a 9-point effort scale, and if there are upper and lower speech rate boundaries for receiving ratings of “highly natural sounding” speech during chorus reading. Learning outcomes: The reader will be able to: (1) describe the effect of changes in speech rate on the frequency of short phonated intervals during chorus reading, (2) describe changes to speaker-judged speech effort as speech rate changes during chorus reading, (3) and describe the effect of changes in speech rate on listener-judged naturalness ratings during chorus reading.
Rac Activation: P-Rex1 — A Convergence Point for PIP3 and Gβγ?

P-Rex1, a novel Rac activator, has been identified in the first biochemical purification of a guanine nucleotide exchange factor for GTPases of the Rho family. P-Rex1 is synergistically activated by PIP3 and Gβγ and may act as a coincidence detector for these signaling molecules.
Supersymmetry Breaking in SQCD

It is established that (massive) Supersymmetric Quantum Chromodynamics (SQCD) breaks supersymmetry in a long lived state. We review some of the key properties of this state and motivate the search for alternative models. We outline the dynamics of SQCD with both massive and massless quarks and explain how a drawback of the original models is solved.
Assessment of antiarrhythmic drug efficacy in the treatment of supraventricular arrhythmias

Few guidelines exist for judging the efficacy of antiarrhythmic drugs in patients with supraventricular arrhythmias. Useful definitions concerning the frequency and duration of supraventricular arrhythmias are offered, and complete and partial efficacy criteria are outlined for noninvasive electrocardiographic and invasive electrophysiologic techniques. Several open label, double-blind, parallel and crossover study designs are suggested for efficacy studies concerning the termination and prevention of supraventricular tachycardia. These recommendations are useful for designing new drug trials needed to evaluate properly the efficacy of antiarrhythmic agents in the treatment of various supraventricular arrhythmias.
Patient-specific modeling of biomechanical interaction in transcatheter aortic valve deployment

The objective of this study was to develop a patient-specific computational model to quantify the biomechanical interaction between the transcatheter aortic valve (TAV) stent and the stenotic aortic valve during TAV intervention. Finite element models of a patient-specific stenotic aortic valve were reconstructed from multi-slice computed tomography (MSCT) scans, and TAV stent deployment into the aortic root was simulated. Three initial aortic root geometries of this patient were analyzed: (a) aortic root geometry directly reconstructed from MSCT scans, (b) aortic root geometry at the rapid right ventricle pacing phase, and (c) aortic root geometry with surrounding myocardial tissue. The simulation results demonstrated that stress, strain, and contact forces of the aortic root model directly reconstructed from MSCT scans were significantly lower than those of the model at the rapid ventricular pacing phase. Moreover, the presence of surrounding myocardium slightly increased the mechanical responses. Peak stresses and strains were observed around the calcified regions in the leaflets, suggesting the calcified leaflets helped secure the stent in position. In addition, these elevated stresses induced during TAV stent deployment indicated a possibility of tissue tearing and breakdown of calcium deposits, which might lead to an increased risk of stroke. The potential of paravalvular leak and occlusion of coronary ostia can be evaluated from simulated post-deployment aortic root geometries. The developed computational models could be a valuable tool for pre-operative planning of TAV intervention and facilitate next generation TAV device design.
Removal of Aqueous Phenol by Adsorption and Oxidation with Doped Hydrophobic Cryptomelane-Type Manganese Oxide (K−OMS-2) Nanofibers

Molecular adsorption and oxidation at manganese oxide/liquid interfaces has attracted increased interest due to its importance in the development of heterogeneous catalysts, microbial fuel cells, and selective adsorption materials. Here we report the adsorption and oxidation of phenolic compounds on Cu2+, Co3+, and Ce4+ doped K−OMS-2 nanofibers. Different metal ion doped K−OMS-2 catalysts show distinct adsorption and oxidation ability. The structure and compositions of doped K−OMS-2 catalysts were characterized by X-ray diffraction and atomic absorption analyses. The relationships of catalyst structure-catalytic properties were discussed. The adsorbed polymeric nanospheres on doped K−OMS-2 nanofibers were investigated by field emission scanning electron microscopy, Fourier transform infared spectroscopy, transmission electron microscopy, and energy dispersive X-ray analyses. These nanospheres were totally oxidized to CO2 in oxygen or air at 553−603 K catalyzed by doped and undoped K−OMS-2 itself. OMS-2 wa...
Active removal of biochar by earthworms (Lumbricus terrestris)

Abstract The role earthworms play in the cycling of biochar in the soil column is poorly understood. While some studies show that earthworms favor a biochar-rich environment, they are ambiguous as to whether earthworms actively remove it and/or possibly consume it, or whether biochar indirectly provides a more favorable habitat. More importantly, associating the properties of different biochars to habitat preference by earthworms has received almost no attention. Courts were established with eight biochars from different feedstocks with varying in physicochemical properties. Circular piles (1.5 g) of biochar were applied to the surface of mesocosms containing field soil and 25 earthworms. Removal was quantified by digitally photographing the biochar samples and visually estimating disappearance over time. Most biochars were actively removed by the earthworms. The most preferred biochar was an aged biochar (>70 years) harvested from charcoal mounds, whereas the least preferred was a fast-pyrolysis biochar made from hardwood sawdust. There was an inverse relationship between the removal of biochar by earthworms and total carbon and a proportional increase with the contents of ash, Ca, Mn, and Si, although the correlations were not strong and may not explain earthworm preference. Other physicochemical properties of the biochars, such as the % volatile C, % H, porosity, and cumulative surface area, were associated with increased aerobic bacteria and fluorescent pseudomonads in soil, but not associated with biochar removal by earthworms. More research is needed to determine if tailoring specific biochars for surface removal by earthworms could be achieved by supplementing biochar with Ca, Mn, and Si and thus lead to a non-disruptive system for delivery of biochar into lower soil horizons of perennial crops. More importantly, this procedure may be useful in screening biochars for attractiveness to earthworms.
Opportunities for Women to Acquire Gainful Employment in the Alternative Sector in Berlin

The alternative sector still offers women substantial and meaningful advantages over the formal sector in employment. A project group, “Women in the Labour Market”, associated with the Department of Economics at the Freie Universitat Berlin in 1983 set out to study the opportunities for women to acquire gainful employment within the alternative sector and to examine the choices offered and the quality of employment attained within the projects examined. Co‐workers of 22 different projects (eight all‐women and 14 mixed) in crafts/manufacturing, transport, retail, trade, service sector and social services in Berlin were interviewed. All projects consciously tackled problems arising with an uneven distribution or assignment of tasks and information by concrete actions. Some branches required a specialised qualification or training, others did not. Gender‐specific work divisions are still found. However, these issues are being positively addressed. Care is needed to avoid repressive and unchangeable structure...
Catalytic degradation of medium density polyethylene over silica-alumina supports

Abstract A series of amorphous silica-alumina catalysts with similar surface area has been prepared by sol-gel chemistry. We report the results of a study of the role of catalyst acidity on the distribution and quality of the products obtained from the degradation of medium density polyethylene (MDPE). The activity of these catalysts was evaluated with and without a hydrogen donor solvent (tetralin), under high hydrogen pressure (5.5 MPa) and moderate temperatures (653–723 K). It was found that the production of oils from the conversion of MDPE correlated with the Bronsted acidity and not with the total acidity of the catalysts. The presence of the hydrogen donor solvent inhibited the activity of the catalysts and lead to an increase in the molecular weight of the oils.
Polypurine Tract Primer Generation and Utilization by Moloney Murine Leukemia Virus Reverse Transcriptase

During reverse transcription, the RNase H activity of reverse transcriptase specifically cleaves the viral genome within the polypurine tract (PPT) to create the primer used for the initiation of plus-strand DNA synthesis and nonspecifically cleaves the viral genome to facilitate synthesis of plus-strand DNA. To understand how primer length and sequence affect generation and utilization of the PPT, we employed short hybrid substrates containing or lacking the PPT to evaluate cleavage, extension, and binding by reverse transcriptase. Substrates containing RNAs with the correct 3' end for initiation of plus-strand synthesis were extended equally well by reverse transcriptase, but primer length affected susceptibility to RNase H cleavage. RNA substrates with 3' ends extending beyond the plus-strand initiation site were extended poorly but were specifically cleaved to generate the correct 3' end for initiation of plus-strand synthesis. Substrates containing RNAs lacking the PPT were cleaved nonspecifically and extended inefficiently. Specific cleavages to generate the plus-strand primer and 5'-end-directed cleavages were kinetically favored over cleavages that destroyed the PPT primer or degraded other short RNA fragments. The PPT was not intrinsically resistant to cleavage by the isolated RNase H domain, and the isolated polymerase domain extended RNA primers containing the PPT sequence irrespective of the primer 3' end. These results provide insights into how reverse transcriptase generates and selectively utilizes the PPT primer for initiation of plus-strand DNA synthesis.
Space charge dynamics in thermally poled fused silica

Measurements of the transient behavior of both the second-harmonic generation signal and the poling current for type-II fused silica samples under a variety of poling histories are reported. The applied voltage was switched between +5 kV, 0 V, and −5 kV with the sample maintained at 275°C. Observations include: multiple time scales (seconds to minutes) for development of the non-linearity depending on the poling history; a transient second-harmonic signal on the new cathode side of the sample following voltage reversal; and hysteretic incubation intervals before growth of the non-linearity. These observations are incompatible with the usual single mobile ion (e.g. Na+) model for establishing the strong local electric field that leads to the non-linearity. An expanded model including ion-exchange between a high mobility ion (as Na+) and a much lower mobility ion (related to H+) provides a good qualitative fit to the experiments.
The forest becomes desert: forest use and environmental change in Tanzania's West Usambara mountains

This paper examines how changing indigenous and Western cultural conceptions of northeastern Tanzania's West Usambara forests played themselves out both in struggles over resources and processes of ecological change. Using oral and documentary sources, it explains how pre-colonial indigenous societies placed value on forest resources, as well as their broad patterns of forest exploitation. It follows with a discussion of the period beginning in the late 19th century and ending in the early 1960s, when indigenous forest users saw their access to forest resources severely restricted by an increasingly powerful colonial state. Finally, it describes the events immediately following Tanzania's independence in 1961, when government officials turned over to peasant farmers large areas of the colonial forest reserve. Each of the four periods covered here—pre-colonial, German colonial, British colonial, and independence—is ultimately over the character of the forest environment and the soils which support it. Copyright © 1999 John Wiley & Sons, Ltd.