cssi/SciSciGPT-SciSciNet huggingface dataset:
Stages-Based ECG Signal Analysis From Traditional Signal Processing to Machine Learning Approaches: A Survey

Electrocardiogram (ECG) gives essential information about different cardiac conditions of the human heart. Its analysis has been the main objective among the research community to detect and prevent life threatening cardiac circumstances. Traditional signal processing methods, machine learning and its subbranches, such as deep learning, are popular techniques for analyzing and classifying the ECG signal and mainly to develop applications for early detection and treatment of cardiac conditions and arrhythmias. A detailed literature survey regarding ECG signal analysis is presented in this article. We first introduce a stages-based model for ECG signal analysis where a survey of ECG analysis related work is then presented in the form of this stage-based process model. The model describes both traditional time/frequency-domain and advanced machine learning techniques reported in the published literature at every stage of analysis, starting from ECG data acquisition to its classification for both simulations and real-time monitoring systems. We present a comprehensive literature review of real-time ECG signal acquisition, prerecorded clinical ECG data, ECG signal processing and denoising, detection of ECG fiducial points based on feature engineering and ECG signal classification along with comparative discussions among the reviewed studies. This study also presents a detailed literature review of ECG signal analysis and feature engineering for ECG-based body sensor networks in portable and wearable ECG devices for real-time cardiac status monitoring. Additionally, challenges and limitations are discussed and tools for research in this field as well as suggestions for future work are outlined.
Finite gyro-radius multidimensional electron hole equilibria

Finite electron gyro-radius influences on the trapping and charge density distribution of electron holes of limited transverse extent are calculated analytically and explored by numerical orbit integration in low to moderate magnetic fields. Parallel trapping is shown to depend upon the gyro-averaged potential energy and to give rise to gyro-averaged charge deficit. Both types of average are expressible as convolutions with perpendicular Gaussians of width equal to the thermal gyro-radius. Orbit-following confirms these phenomena but also confirms for the first time in self-consistent potential profiles the importance of gyro-bounce-resonance detrapping and consequent velocity diffusion on stochastic orbits. The averaging strongly reduces the trapped electron deficit that can be sustained by any potential profile whose transverse width is comparable to the gyro-radius $r_g$. It effectively prevents equilibrium widths smaller than $\sim r_g$ for times longer than a quarter parallel-bounce-period. Avoiding gyro-bounce resonance detrapping is even more restrictive, except for very small potential amplitudes, but it takes multiple bounce-periods to act. Quantitative criteria are given for both types of orbit loss.
Calcaneal shape variation in humans, nonhuman primates, and early hominins

Abstract The foot has played a prominent role in evaluating early hominin locomotion. The calcaneus, in particular, plays an important role in weight-bearing. Although the calcanei of early hominins have been previously scrutinized, a three-dimensional analysis of the entire calcaneal shape has not been conducted. Here, we investigate the relationship between external calcaneal shape and locomotion in modern Homo sapiens (n = 130), Gorilla (n = 86), Pan (n = 112), Pongo (n = 31), Papio (n = 28), and hylobatids (Hylobates, Symphalangus; n = 32). We use these results to place the calcanei attributed to Australopithecus sediba, A. africanus, A. afarensis, H. naledi, and Homo habilis/Paranthropus boisei into a locomotor context. Calcanei were scanned using either surface scanning or micro-CT and their external shape analyzed using a three-dimensional geometric morphometric sliding semilandmark analysis. Blomberg's K statistic was used to estimate phylogenetic signal in the shape data. Shape variation was summarized using a principal components analysis. Procrustes distances between all taxa as well as distances between each fossil and the average of each taxon were calculated. Blomberg's K statistic was small (K = 0.1651), indicating weak phylogenetic effects, suggesting variation is driven by factors other than phylogeny (e.g., locomotion or body size). Modern humans have a large calcaneus relative to body size and display a uniquely convex cuboid facet, facilitating a rigid midfoot for bipedalism. More arboreal great apes display relatively deeper cuboid facet pivot regions for increased midfoot mobility. Australopithecus afarensis demonstrates the most human-like calcaneus, consistent with obligate bipedalism. Homo naledi is primarily modern human-like, but with some intermediate traits, suggesting a different form of bipedalism than modern humans. Australopithecus africanus, A. sediba, and H. habilis/P. boisei calcanei all possess unique combinations of human and nonhuman ape-like morphologies, suggesting a combination of bipedal and arboreal behaviors.
Design of conceptual search engine using hierarchy of attributes and concepts

This paper discusses about methodology to implement a search engine. Most of the common techniques employed in search engine are based on the term frequency. To achieve a more accurate analysis, the underlying representation should indicate terms that capture the concepts of text. In this paper we present how the concepts can be represented using Hierarchy of Attributes and concepts using clustering technique and propose a methodology to extract documents against a query using this method. Initially, the entire space of terms could be generated by a set of (linearly) independent terms over a numerical field. The total number of concepts to be generated over a numerical field using a given number of attributes. An algorithmic implementation of Hierarchy of concepts and attributes (HAC) is developed and experimental results are presented using concepts from the field of education.
Illumination and Person-Insensitive Head Pose Estimation Using Distance Metric Learning

Head pose estimation is an important task for many face analysis applications, such as face recognition systems and human computer interactions. In this paper we aim to address the pose estimation problem under some challenging conditions, e.g., from a single image, large pose variation, and un-even illumination conditions. The approach we developed combines non-linear dimension reduction techniques with a learned distance metric transformation. The learned distance metric provides better intra-class clustering, therefore preserving a smooth low-dimensional manifold in the presence of large variation in the input images due to illumination changes. Experiments show that our method improves the performance, achieving accuracy within 2-3 degrees for face images with varying poses and within 3-4 degrees error for face images with varying pose and illumination changes.
The Reactions of the Sulfhydryl Groups of Human Hemoglobin β4

Abstract The rates at which the sulfhydryl groups on each chain of hemoglobin β4 react with N-ethylmaleimide and iodoacetate have been measured. The sulfhydryl group at position 93 reacts with both alkylating agents at approximately the same rate as normal liganded hemoglobin. The sulfhydryl group at position 112, which is not available in normal hemoglobin, reacts in hemoglobin β4 and does so much more rapidly than does the sulfhydryl at position 93. The rapidly and slowly reacting groups were identified by isolation of tryptic peptides labeled with 14C-N-ethylmaleimide or 14C-iodoacetate. Because of the different rates of reaction of the two sulfhydryl groups, it was possible to produce a derivative carboxymethylated only at position 112. This modification makes the β chains unable to form tetramers. They have a sedimentation coefficient of 1.88 S which corresponds to monomers.
Template Synthesis of Nanostructured Metals using Cellulose Nanocrystal

In this chapter, cellulose nanocrystal (CNXL) has been used as a template and reducing agent for synthesizing nanoscale inorganic solids such as metal oxide, metal carbide, and nanocrystalline metals. CNXL selectively nucleates metal or metal oxide phases in ordered arrangements commensurate with the attendant structure and chemistry of the fiber. The reaction has an analogy to the well-known Tollen’s reagent where addition of an aldehyde or glucose analyte to a glass vessel containing a soluble ammoniacal silver complex causes reduction of the silver to form a mirror on the vessel surface. For the synthesis of TiO2, CNXL produced mesoporous anatase with 5-10 nm particle sizes and 170-200 m2/g surface area after air-calcination. Silica-infiltrated CNXL produced very homogeneous SiC nanowires with 70 nm in diameter at 1400 oC in Ar. For the syntheses of metal nanoparticles, upon addition of aqueous metal ion containing solutions (Cu(II), Ni(II), Ag(I), Au(III), Pd(II), Pt(IV), or even selenite, Se(IV)) into the CNXL suspension, reduction to the metal occurs under hydrothermal conditions to form ordered metal nanostructures. Ni (II) and Cu(II) ions required high temperature (300-400 oC) to be reduced due to their low reduction potentials. However, metal ions including Ag(I), Au(III), Pt(IV), Pd(II), Se(IV) needed lowermore » temperatures (160-200 oC) to be reduced. Enhanced catalytic activity on these templated surfaces has been demonstrated for a methylene-blue dye photo-induced decomposition (Se nanocrystals resident on crystalline cellulose).« less
Optical tolerancing and principal component analysis

This work explores the use of linear principal component analysis (PCA) during an optical design’s tolerancing analysis. Chapman et al. [Proc. SPIE3331, 102 (1998)PSISDG0277-786X] have shown the usefulness of the singular value decomposition in realizing an alignment algorithm for a system. This paper explores some insights that can be gained from performing PCA on the Monte Carlo data set obtained during the tolerancing step and comparing it with the singular components of the Jacobian (sensitivity matrix) of the system.
The Instability of Neurospora Duplication Dp(IL→IR)H4250 , and Its Genetic Control

Previous work (Newmeyer and Taylor 1967) showed that a nontandem duplication, Dp(IL→IR)H4250, is regularly produced by recombination in crosses heterozygous for the effectively terminal pericentric inversion In(IL→IR)H4250. The duplications initially have strongly inhibited growth because they are heterozygous for mating type, which behaves like a vegetative-incompatibility (het) locus. Such cultures "escape" from the inhibition as a result of events that eliminate the mating-type heterozygosity. The product of a given escape event may be barren or fertile. (Neurospora duplications are characteristically barren; that is, when crossed, they make many perithecia but few ascospores.)—The present paper reports on a genetic analysis of the instability of Dp(IL→IR)H4250 . Most of the barren escape products behave as if due either to mitotic crossovers, which make mating type and distal markers homozygous, or to very long deletions which uncover mating type and all distal markers; presumably the latter would retain enough duplicated material to render them barren. It is difficult to distinguish between these two possibilities, but homozygosis seems more probable and has been clearly demonstrated in one case. Only a few barren escapes could be due to short deletions or to changes at the mating-type locus.—The fertile escape products appear to be euploid. Most of these behave as if they arose by precise deletion of one or the other duplicated segment, thus restoring one of the parental sequences. A large majority of the precise deletions restore normal sequence; only a few restore inversion sequence. Preferential restoration of the normal sequence has also been found by other workers for Neurospora duplications from several other rearrangements. A hypothesis is presented to explain these findings; it is posulated that the precise deletions result from mitotic crossing over in homologous material located at chromosome tips and tip-break-points.—There is a smaller group of fertile escapes that are unlike either parental sequence; at least one of these involves a chromosome break outside the duplicated region.—Duplications in which the vegetative incompatibility is suppressed by the unlinked modifier tol are extremely barren; they only rarely lose a duplicated segment so as to become fertile.—The instability of Dp(IL→IR)H4250 , with and without tol, is markedly altered by factors in the genetic background. The two factors studied in detail have qualitatively different effects.
Sharing individual research results with biospecimen contributors: counterpoint.

I appreciate Drs. Yassin, Weil, and Lockhart (the authors) giving me the opportunity to respond to their article. I understand the source of the National Cancer Institute's concern. The NCI has many multicenter trials in which local sites submit tumor samples, which are then reviewed centrally by
Using a longitudinal database to assess the validity of preceptors' ratings of clerkship performance.

Purpose. To examine the validity of using scores from a clinical evaluation form as an assessment of clinical competence. Method. Investigators collected a longitudinal clinical skills assessment database that included scores reflecting performance on standardized patient interactions, case-based learning performance, scores on multiple-choice clinical examinations, and preceptors' ratings of students during their clerkships. Pearson correlation coefficients and coefficients corrected for attenuation were calculated between the mean preceptor rating CEF score and the other measures collected during years one and two. Results. Estimates from an earlier across-clerkship generalizability study of the CEF demonstrated that a mean rating computed across 28 forms and four clerkships (the average measurement frequencies observed in this study), yielded an estimated G-coefficient of 0.62 (Kreiter and Ferguson, 2001). Reliabilities for the other measures ranged from 0.23 to 0.56. Nine of the twelve clinical skill measures correlated with the CEF. For those significantly correlated measures where reliabilities could be calculated, correlations corrected for attenuation ranged from 0.46 to 0.58. Conclusion. This study indicates that the skills measured by the CEF are related to other clinical performance measures and, conversely, that pre-clinical measures of skills that are believed to be important during clinical years are in fact predictors of preceptors' ratings of clinical performance later in medical school. In addition, the magnitude of the disattenuated coefficients suggests that ratings on the CEF are dependent on important aspects such as clinical knowledge. This study suggests that when averaged over a large number of observations, mean CEF scores demonstrate validity coefficients large enough to support their use as part of an evaluation of students' clinical performance.
Production of IgE-potentiating factor in man by T cell lines bearing Fc receptors for IgE

The regulation of human IgE production in vitro by soluble T cell factors was examined. T cells were isolated from the peripheral blood of 2 patients with the hyper-IgE syndrome on the basis of their expression of Fc receptors for human IgE (Fc epsilon R). The T cells were incubated with human myeloma IgE (10 micrograms/ml), washed, reacted with immunosorbent-purified goat anti-human IgE conjugated with fluorescein isothiocyanate, and then separated into Fc epsilon R+ and Fc epsilon R- T cells on the fluorescence-activated cell sorter. Fc epsilon R+ T cells and Fc epsilon R- T cells were propagated in culture using supernatants of phytohemagglutinin-stimulated peripheral blood mononuclear cells (PBMC) and irradiated autologous PBMC. Supernatants of Fc epsilon R+ T cell lines but not of Fc epsilon R- T cell lines selectively enhanced IgE synthesis in cultures of B cells obtained from patients with allergic rhinitis but not from normal nonallergic subjects. The surface phenotype of the Fc epsilon R+ T cell line was predominantly T3+, T4+, Ia+ with few (15%) T8+ cells. Two T cell clones were grown from the Fc epsilon R+ T cell line by limiting dilution (0.3 cells/well). These clones possessed the T4+ helper/inducer phenotype and secreted IgE-enhancing factor(s). The IgE-enhancing factor(s) which had affinity for insolubilized human IgE was sensitive to treatment with trypsin and neuraminidase, and had as its target an IgE-bearing B cell. These results suggest that a subset of human T cells bearing an Fc epsilon R secretes an IgE-binding glycoprotein which selectively enhances IgE synthesis by IgE-bearing B cells.
Evaluation of direct and indirect phosphorus limitation of methanogenic pathways in a calcareous subtropical wetland soil

Abstract The effect of phosphorus (P) and carbon (C) on methanogenesis was investigated in a low-P (130 mg P kg −1 soil) wetland within Everglades National Park. Soil was amended with C substrates (acetate, formate, butyrate, and glucose) with or without P, and CO 2 and CH 4 production was monitored. Production of CH 4 increased with P addition although no effect on CO 2 was observed. Methane production was stimulated by all C substrates except for butyrate. No effect of C on CO 2 production was observed except for stimulation following glucose addition. Production of CH 4 following formate addition was not affected by P, suggesting hydrogenotrophic methanogens may be substrate, not P, limited. Addition of P to all other C substrates heightened CH 4 production and lowered the CO 2 –C:CH 4 –C ratio relative to the corresponding C only treatment, suggesting that P may have limited acetoclastic methanogens and fermentation.
“And You Were There”: A Trip Down the Yellow Brick Road with the Academic Study of Religion

Abstract: In a world of proliferating entertainment options and increasingly fragmented fandoms, The Wizard of Oz (1939) remains a rare touchstone of shared cultural familiarity. Yet, while film scholars and historians have examined the movie extensively, not so scholars interested in what relevance it holds for the academic study of religion. This paper serves as an introduction to a roundtable designed to begin redressing that omission. I argue, as the contributions that come next skillfully demonstrate, that following the Yellow Brick Road with Dorothy and her friends reveals productive opportunities to explore the North American religious experience.
Video-conferenced music teaching: challenges and progress

This article reports on a study that aimed to explore general classroom music teaching and learning via video-conferencing between pre-service music teachers in the USA, and students at an elementary school for underprivileged children in Mexico. This study examines the challenges, progress and lessons learned as interactions within this developing medium are refined. Data include researcher narrative, teacher reflections and student writings collected over a two-year period. Results indicate that there are benefits and drawbacks to teaching and learning in the video-conferenced environment. The implication for music education is that video-conferencing is a feasible way of facilitating music teaching and learning between teachers and students in distant locations anywhere in the world, and music educators should consider this opportunity for increased musical exchange and cultural interaction.
Comment on the Review of MAN IN PREHISTORY

obvious, indeed the almost inevitable choice in South Africa, all the more so that practically all dark-skinned people were in fact "heathens," and that darkness was traditionally associated with sin and evil in the Christian world view. Hypothetical as this interpretation may seem, it is supported by the constant attempts on the part of fundamentalistic Afrikaners to seek Biblical justification for racial segregation and White superiority [pp. 14-15].
SOFTWARE TOOLKIT FOR TEACHING IMAGE PROCESSING

We introduce a software framework called the Java Vision Toolkit (JVT) for teaching image processing and computer vision. The toolkit provides over 50 image operations and presents them to the user in a GUI that can render grayscale, color and 3D range images. The software is written in Java, enabling it to be integrated into HTML documents and interactive course materials. The framework is designed for extensibility using a source code template that supports the implementation of any new operation with a minimal amount of supporting code. For students, this framework encapsulates the GUI, file I/O and other trivial programming details and allows them the maximum amount of time to spend on understanding computer vision. We compare the JVT with other computer vision software frameworks that are used for teaching and research. We also discuss the use of the JVT in an undergraduate image processing course at the University of South Florida.
Non-allosteric regulation of the uridine kinase from seeds of Zea mays.

Abstract Uridine kinase (ATP: uridine 5′-phosphotransferase, EC 2.7.1.48) has been partially purified from ungerminated hybrid corn seed. It is associated with a soluble high molecular weight fraction from which it apparently cannot be dissociated without loss of activity. The stability of the enzyme is enhanced by the addition of dithiothreitol, glycerol and nucleotide substrate. The nucleoside specificity of the enzyme is limited to nucleosides containing pyrimidine and ribose moieties, such as uridine and cytidine. High concentrations of nucleosides cause substrate inhibition, however. The K m values for uridine and cytidine are 53 μM and 125 μM, respectively, and under subsaturating conditions uridine is phosphorylated about five times faster than cytidine. The reaction follows an ordered Bi Bi Kinetic pattern, with ATP and ADP in competition for the free form of the enzyme. Purine, but not pyrimidine, nucleoside triphosphates serve as phosphate donors without regard to the sugar moiety. However, all of these triphosphates appear to compete for the same site on the enzyme. ( K m ATP = 590 μM , K m (app) GTP = 61 μM , and CTP and UTP are linear competitive inhibitors against ATP, with Ki values of 60μM and 240 μM, respectively.) Therefore, end product control of uridine kinase apparently does not involve allosteric sites, but instead is envisioned as simple competition between relatively effective or ineffective phosphate donors for a position on the enzyme.
Vanadium-based ohmic contacts to n-type Al0.6Ga0.4N

Four vanadium-based contacts to n-type Al0.6Ga0.4N were compared in this work. Both V/Al/Pd/Au and V/Al/V/Au contacts with optimized layer thicknesses provided lower specific-contact resistances than did the previously reported V/Al/Pt/Au ohmic contact. Specific contact resistances of the V/Al/Pd/Au (15 nm/85 nm/20 nm/95 nm) and V/Al/V/Au (15 nm/85 nm/20 nm/95 nm) contacts were 3×10−6 Ω·cm2 and 4×10−6 Ω·cm2, respectively. On the other hand, an analogous V/Al/Mo/Au contact never became ohmic, even after it was annealed at 900°C for 30 sec. Compared to the V/Al/Pd/Au contact, the V/Al/V/Au contact required a less severe annealing condition (30 sec at 700°C instead of 850°C). The V/Al/V/Au contact also provided a smoother surface, with a root-mean-square (RMS) roughness of 39 nm.
Influence of ketamine, phenylcyclidine, and phenobarbital on cholesterol metabolism in rats.

SummaryThe effects of ip injections of phenobarbital (100 mg/kg), phenylcycli-dine (Sernylan; [l-(l-phenylcyclohexyl)-piperidine-HCl] (1 mg/kg), and ketam-ine (Ketaset; [dl(2-O-chlorophenyl)-2-(methylamino)cyclohexanone- HC1] (1 mg/ kg) on lipid metabolism in rats were compared. This study was undertaken to determine whether the two sedatives currently used in primates share any of the undesirable effects of phenobarbital on lipid metabolism. All three compounds were administered to male Wistar rats for 6 days. Phenobarbital was hepatomegalic, stimulated 7α hydroxylation of cholesterol, and inhibited cholesterol synthesis by rat liver slices from mevalonate, but not acetate. The two other sedatives exhibited effects very similar to those observed in the controls. From our work in rats it is concluded that the use of Sernylan or Ketaset for sedation of nonhu-man primates will not significantly affect these parameters of lipid metabolism.
Transient ULF Electric and magnetic fields of an electrical current source in a medium with continuously varying conductivity

Recent analytical studies of ULF electromagnetic fields in the atmosphere are reviewed. These fields have their origin in the discharge of thunderclouds. The problem for a vertical electrical dipole source played in an atmosphere where the conductivity increases exponentially with altitude is described. The analytical expressions for the electric and magnetic field, which vary in time and space, are approximately obtained by a vector potential. It is seen that the amplitudes of the pulse decrease with both increases of the horizontal distance and the gradient of the conductivity. However, the shapes of the pulse are almost constant.
Pleasure, Freedom and Grace: Schiller's “Completion” of Kant's Ethics∗

Kant famously begins his analysis of what he calls “common rational cognition” about morality by proclaiming that only the good will has unlimited value (Gr 4: 393; 49).1 The good will's supreme va...
Helicopter flight-control design using an H(2) method

Rate-command and attitude-command flight-control designs for a UH-60 helicopter in hover are presented and were synthesized using an H(2) method. Using weight functions, this method allows the direct shaping of the singular values of the sensitivity, complementary sensitivity, and control input transfer-function matrices to give acceptable feedback properties. The designs were implemented on the Vertical Motion Simulator, and four low-speed hover tasks were used to evaluate the control system characteristics. The pilot comments from the accel-decel, bob-up, hovering turn, and side-step tasks indicated good decoupling and quick response characteristics. However, an underlying roll PIO tendency was found to exist away from the hover condition, which was caused by a flap regressing mode with insufficient damping.
The Spectral Reflectance of Natural Surfaces

The amount of solar energy reflected from various soils and types of vegetation has been measured as a function of sun elevation in six different wavelength ranges in the ultraviolet, visible and near-infrared regions of the spectrum. It is shown that there is a significant dependence of reflectance on both wavelength and elevation of the sun for all surfaces for which measurements were made.
Theory of dynamic light scattering by polymers and gels

Abstract It is shown under very general conditions that the intermediate scattering function for the generalized Rouse—Zimm model always takes the simple form G(K, t) α exp[−K2(kBT/f)t], when the scattering vector K becomes sufficiently large. (Here kB is Boltzmann's constant, T is the absolute temperature and f is the individual bead friction factor.) A microscopic formulation for the bulk modulus and friction factor density of a gel network is incorporated into the viscoelastic continuum model of Tanaka et al. The resulting expression for the apparent long-wavelength diffusion coefficient of the gel is DG = (kBT/f)2(1 - 2/Φ), where Φ is the network functionality.
Mental Health and Other Service Use by Youth in Therapeutic Foster Care and Group Homes

Little is known about what additional services youth receive while they reside in out-of-home treatment settings. However, such information may be crucial for explaining effectiveness and variation in outcomes for youth in such settings. Our research examines patterns of multi-sector service use for youth in two settings—Therapeutic Foster Care and group homes. Data come from in-person interviews with Treatment Foster Parents and Group Home Staff for a NC state-wide sample of youth with psychiatric disorders and aggressive behavior. Findings indicated high rates of service use by youth in both settings. Analyses indicated significant differences in service types used by youth in each setting, yet similar volume of service use between settings. Clinical and demographic factors did not significantly influence types of services received. Differences in service patterns between the two groups indicated that youth in TFC were more likely to receive community-based, individualized services while youth in group homes were more likely to receive more restrictive services.
Excess argon in deep-sea rocks.

Excess radiogenic argon in deep sea basalts from crest of East Pacific Rise, noting relation to glass content
Biosynthesis of (—)-Kaurene in Cell-free Extracts of Immature Pea Seeds

Mevalonate-(14)C was incorporated into (-)-kaurene-(14)C in cell-free extracts of immature pea (Pisum sativum L.) seeds. The identification of (14)C-product as (-)-kaurene was based on: A) comparison with authentic (-)-kaurene on thin-layer and gas-liquid chromatography; and B) oxidation of (14)C-product and (-)-kaurene with osmium tetroxide to form the common derivative kaurane-16,17-diol. The enzyme system is heat labile and is dependent upon ATP and Mg(2+) or Mn(2-), with Mn(2+) being a more effective activator than Mg(2+). The reaction rate was proportional to enzyme concentration in reaction mixtures containing 0.45 to 1.8 mg protein n/ml, and was linear with time through 120 minutes in standard reaction mixtures. Enzyme preparations from immature seeds of tall and dwarf peas appeared to synthesize (-)-kaurene at the same rate. Synthesis of (-)-kaurene was readily inhibited by Amo-1618. (2-Chloroethyl)-trimethylammonium chloride (CCC) also inhibited (-)-kaurene synthesis; however, approximately 1000-fold higher concentrations of CCC were required to evoke the same percentages of inhibition as Amo-1618.
Images of divalent cations in unstained symmetric and asymmetric lipid bilayers

Abstract Divalent cations have been microscopically visualized in association with simple lipid bilayers. Symmetric and asymmetric oriented bilayers were constructed from fatty acid monolayers and were cut in thin transverse sections for examination by bright field electron microscopy in the absence of stains, fixatives or embedding materials. It has been found that bilayers formed of lipid molecules having alkaline earth head groups exhibit natural electron contrast. The intrinsic image has been linked to local variations in the bilayer absolute electron density profile determined by X-ray diffraction analysis of the same specimens (McIntosh, T.J., Waldbillig, R. C. and Robertson J. D. (1976) Biochim. Biophys. Acta 448, 15–33). By combining the microscopic, chemical and X-ray evidence it has been estimated that local increments of about 1 g/cm3 can produce detectable electron contrast in 500 A transverse sections of bilayers.
Potential Biological Fate of Emulsion-Based Delivery Systems: Lipid Particles Nanolaminated with Lactoferrin and β- lactoglobulin Coatings

Purpose To develop lipid particles coated by nanolaminated protein coatings as potential oral delivery systems to encapsulate, protect, and deliver lipophilic bioactives.
Subepyndemal hemangioblastomas of the cervicomedullary junction: lessons learned in the management of two cases.

Objective This retrospective case series analyzes two cases of hemangioblastomas in the cervicomedullary junction.
Nonlinear logarithmic time decay of magnetization in a single crystal of Bi2Sr2CaCu2Ox.

Nonlinear logarithmic time decay of magnetization has been observed over a long measuring time period ({ital t}=22 h) for a single crystal of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub {ital x}}. At relatively low temperatures ({ital T}=12 K) linear ln({ital t}) decay of the magnetization is observed for field (=1 kG) parallel to the {ital c} axis, which can be described well by the Anderson-Kim model. However, at high temperatures ({ital T}{gt}26 K) the magnetization exhibits nonlinear logarithmic time near the irreversibility line. Possible connections between the experimental data and current theories are discussed.
Protective effect of α-tocopherol on brain cell membrane function during cerebral cortical hypoxia in newborn piglets

Protective effect of alpha-tocopherol on the structure and function of brain cell membranes was investigated by measuring Na+,K(+)-ATPase activity and products of lipid peroxidation (fluorescent compounds) in brain cell membranes obtained from newborn piglets. Four groups of anesthetized, ventilated piglets were studied: five hypoxic piglets and five normoxic piglets were pretreated with free alpha-tocopherol (20 mg/kg/dose i.m.), five additional hypoxic piglets received i.m. placebo and five normoxic piglets served as control. Placebo and alpha-tocopherol were given 48 and 3 h prior to onset of hypoxia. Hypoxic hypoxia was induced and cerebral hypoxia was documented as a decrease in the ratio of phosphocreatine to inorganic phosphate (PCr/P(i)) using 31P NMR spectroscopy. PCr/P(i) decreased from baseline of 2.62 +/- 0.54 to 1.05 +/- 0.27 in alpha-tocopherol-pretreated and from 2.44 +/- 0.48 to 1.14 +/- 0.30 in the placebo-pretreated group during hypoxia. Na+,K(+)-ATPase activity was unchanged in both normoxic and hypoxic alpha-tocopherol-pretreated groups. However, in placebo-pretreated hypoxic group, Na+,K(+)-ATPase activity decreased as compared with control (44.9 +/- 9.7 vs. 61.8 +/- 5.7 mumol P(i)/mg protein/h, P < 0.005). The level of fluorescent compounds increased in placebo-pretreated but not in alpha-tocopherol-pretreated group as compared with control. During hypoxia, serum alpha-tocopherol levels were higher in alpha-tocopherol-pretreated groups as compared with placebo-pretreated hypoxic group. The present data indicates that alpha-tocopherol protects brain cell membranes in newborn piglets from lipid peroxidative damage during tissue hypoxia probably by being incorporated in cell membrane and also as circulating antioxidant.
Brief Semi-global robust stabilization of MIMO nonlinear systems by partial state and dynamic output feedback

We study the problem of semi-global robust stabilization for a class of multi-input multi-output (MIMO) uncertain nonlinear systems which cannot be transformed, via a change of coordinates and a state feedback, into a lower dimensional zero dynamics driven by a set of chains of integrators, but more complicated interconnected structures. The systems considered here, which distinguish from those studied early in the literature, possess a new feature that they are non-affine in the control inputs. Sufficient conditions are presented for the existence of a linear high-gain partial state controller and/or a nonlinear dynamic output compensator, achieving robust semi-global asymptotic stability. Both the partial state and output dynamic controllers are also explicitly constructed.
Riding the crest of the wave: parallels between the neural crest and cancer in epithelial‐to‐mesenchymal transition and migration

The neural crest (NC) is first induced as an epithelial population of cells at the neural plate border requiring complex signaling between bone morphogenetic protein, Wnt, and fibroblast growth factors to differentiate the neural and NC fate from the epidermis. Remarkably, following induction, these cells undergo an epithelial-to-mesenchymal transition (EMT), delaminate from the neural tube, and migrate through various tissue types and microenvironments before reaching their final destination where they undergo terminal differentiation. This process is mirrored in cancer metastasis, where a primary tumor will undergo an EMT before migrating and invading other cell populations to create a secondary tumor site. In recent years, as our understanding of NC EMT and migration has deepened, important new insights into tumorigenesis and metastasis have also been achieved. These discoveries have been driven by the observation that many cancers misregulate developmental genes to reacquire proliferative and migratory states. In this review, we examine how the NC provides an excellent model for studying EMT and migration. These data are discussed from the perspective of the gene regulatory networks that control both NC and cancer cell EMT and migration. Deciphering these processes in a comparative manner will expand our knowledge of the underlying etiology and pathogenesis of cancer and promote the development of novel targeted therapeutic strategies for cancer patients. © 2013 Wiley Periodicals, Inc.
Profiling proteinuria in pediatric patients

This study was designed to characterize proteinuria in children with kidney disease. Random urine samples from 250 pediatric patients were examined by quantitative measures of total protein (pr), albumin (Alb), and creatinine (cr). Patient diagnoses were subjectively categorized as “Glomerular” (GD) or “Tubulo-interstitial” disease (TD) in origin. Proteinuria was quantitated by the random urine protein-to-creatinine (Upr/cr) ratio, and glomerular proteinuria was assessed as the albumin-to-creatinine ratio (Ualb/cr) and percentage albuminuria (%Alb=Alb/pr*100). The non-albumin fraction (1−Alb/pr) includes low-molecular-weight proteins and micro- and macroglobulins. Of the 250 patients, 112 (45%) had GD and 138 (55%) had TD. Both proteinuria and albuminuria correlated with a decline in glomerular filtration rate (GFR) (r=−0.4; p 50% in those with GD. In conclusion, random Ualb/cr, Upr/cr, and %Alb provide a simple and inexpensive assessment of proteinuria and may profile renal disease activity and response to therapy in pediatric patients.
Parvalbumin neurons and gamma rhythms enhance cortical circuit performance

Synchronized oscillations and inhibitory interneurons have important and interconnected roles within cortical microcircuits. In particular, interneurons defined by the fast-spiking phenotype and expression of the calcium-binding protein parvalbumin have been suggested to be involved in gamma (30-80 Hz) oscillations, which are hypothesized to enhance information processing. However, because parvalbumin interneurons cannot be selectively controlled, definitive tests of their functional significance in gamma oscillations, and quantitative assessment of the impact of parvalbumin interneurons and gamma oscillations on cortical circuits, have been lacking despite potentially enormous significance (for example, abnormalities in parvalbumin interneurons may underlie altered gamma-frequency synchronization and cognition in schizophrenia and autism). Here we use a panel of optogenetic technologies in mice to selectively modulate multiple distinct circuit elements in neocortex, alone or in combination. We find that inhibiting parvalbumin interneurons suppresses gamma oscillations in vivo, whereas driving these interneurons (even by means of non-rhythmic principal cell activity) is sufficient to generate emergent gamma-frequency rhythmicity. Moreover, gamma-frequency modulation of excitatory input in turn was found to enhance signal transmission in neocortex by reducing circuit noise and amplifying circuit signals, including inputs to parvalbumin interneurons. As demonstrated here, optogenetics opens the door to a new kind of informational analysis of brain function, permitting quantitative delineation of the functional significance of individual elements in the emergent operation and function of intact neural circuitry.
Capturing the Transport Variability of a Western Boundary Jet: Results from the Agulhas Current Time-Series Experiment (ACT)*

AbstractThe volume transport of the Agulhas Current was measured over a 3-yr period by an array of seven current meter moorings and four current- and pressure-recording inverted echo sounders (CPIES) deployed at 34°S. CPIES extended the array farther offshore in order to capture, for the first time, the full Agulhas Current during meander events. Transports derived from CPIES are well correlated with overlapping current meter transports (0.89). The Eulerian mean current is 219 km wide and 3000 m deep, with peak surface speeds of 1.8 m s−1 and a weak northward undercurrent on the continental slope below 1200 m. A new algorithm to capture the western boundary jet transport at each time step T is defined as the poleward transport out to the first maximum of the vertically integrated velocity beyond the half-width of the mean jet. The mean transport of the Agulhas Current jet, so defined, is −84 Sverdrups (Sv; 1 Sv ≡ 106 m3 s−1) with a standard error of 2 Sv. Sampling and instrumental errors are explicitly es...
Soft tissue sarcoma brain metastases. Prevalence in a cohort of 3829 patients.

BACKGROUND Brain metastases from soft tissue sarcoma (STS) are uncommon. To the authors' knowledge limited information is available regarding the influence of the initial STS site, the significance of parenchymal versus leptomeningeal metastases, and the role of surgical resection. METHODS STS patients evaluated between July 1982 and March 1999 who presented with or developed brain metastases were identified from a prospective database. Association between factors was determined using the Fisher exact test. Survival was estimated using the Kaplan–Meier method. The influence of factors on the endpoint (disease specific survival [DSS]) was analyzed using the log-rank test. Significance was defined at P ≤ 0.05. RESULTS A total of 3829 STS patients were evaluated during the study interval; 21 patients presented with and 19 patients subsequently developed brain metastases, accounting for < 1% (40 of 3829 patients) of the total patient group. The STS presentation status for this group of patients (n = 40) included 15 patients with primary STS, 1 patient with local recurrence, and 24 patients with metastatic disease. The most frequent types of STS metastasizing to the brain were leiomyosarcoma (eight patients), liposarcoma (five patients), rhabdomyosarcoma (four patients), and malignant fibrous histiocytoma (MFH) (four patients). Fourteen other sarcoma types were determined in the remaining 19 patients. Of the 19 patients who developed subsequent brain metastases, 18 had lung metastases as the immediate prior site of disease. The median overall follow-up for the 40 patients was 14 months (range, 1–128 months); for survivors (n = 5), the median overall follow-up was 18 months. During follow-up, 34 patients died of disease and 1 patient died of other causes. Brain metastasectomy was performed in 27 of the 40 patients and was highly associated with the initial site of STS; 20 of the 27 patients who underwent resection versus 2 of the 13 patients who did not undergo resection initially had extremity or trunk STS (P < 0.001). No association was observed between parenchymal versus leptomeningeal site of metastases and any outcome factor. The 1-year and 2-year overall DSS for the 40 patients was 55% and 25%, respectively, with a median survival of 15 months. The 1-year and 2-year postmetastasis survival rates were 34% and 20%, respectively, with a median survival of 7 months. Metastasectomy (n = 27) was associated with an improved median postmetastasis survival (9.6 months vs. 2.7 months for unresected patients; P < 0.01). The 2-year postmetastasis survival was 27% for those patients who underwent resection and 0% for the unresected patients. CONCLUSIONS Although brain metastases from STS are rare, vigilance is warranted. Symptomatic patients should be examined neurologically and investigated thoroughly for metastases. Surgical resection may be an appropriate treatment for selected patients; however, survival is dismal. Cancer 2002;94:2706–11. © 2002 American Cancer Society. DOI 10.1002/cncr.10554
Bone erosion in relation to subcutaneous rheumatoid nodules

Two cases of bone erosion produced by subcutaneous rheumatoid nodules about the elbow are reported. The usual pattern of articular and para-articular bone resorption is contrasted with the rare manifestation of bone-scalloping by rheumatoid nodules. Rheumatoid nodules must be included in the differential diagnosis of cortical bone erosions.
COGNITIVE STYLES IN THE DEVELOPMENT OF MEDICAL CAREERS

Recent research has shown that academic choice and achievement may be partly a function of the student's standing on the field-dependence-independence cognitive-style dimension. The results of two longitudinal studies suggest that information about field dependence-independence may be of value for student guidance in the medical setting. The first, a study of college undergraduates who early expressed an interest in medicine, showed that these cognitive styles play a discernible role in determining who will eventually enter medical school. The second, a study of medical students, showed that field-dependent and field-independent students subsequently tend to choose different medical specialties. These results are consistent with cognitive-style theory, which proposes that field-independent people will choose vocations that require cognitive restructuring skills, whereas field-dependent people will choose vocations that require greater social-interpersonal involvement.
The economics of policy borrowing and lending: a study of late adopters

The article draws on interpretive frameworks from diffusion research and social network analysis to explore one particular ‘travelling reform’—outcomes‐based education—that went global. The argument is made that by virtue of studying late adopters of a travelling reform one is examining globalisation. The cases in point for late adoption are Central Asian education systems (in particular Mongolia and Kyrgyz Republic) that borrowed outcomes‐based education reforms at a time when the popularity of similar reforms were already in decline in other countries, notably in New Zealand, Australia and South Africa. The emphasis of this study is on the timing of policy borrowing, and it is suggested that more attention is given to the economics of policy borrowing.
Synthesis and properties of fatty imidazolines and their N-(2-aminoethyl) derivatives

Cationic high molecular weight surfactants hold promise as water repellents for soil for water harvesting. Specifically, the products of the reaction of 2 moles of fatty acids with 1 mole of diethylenetria-mine were investigated. Optimum conditions for the formation of imidazolines as well as the open-chain N-(2-aminoethyl) derivatives, i.e., the diamides, were determined. Saturated fatty acids, pelargonic through behenic, oleic acid, elaidic acid as well as tallow, tallow fatty acids, and hydrogenated tallow fatty acids, were converted in 6 hr at 150 C to form the diamides. The fatty imidazolines were synthesized by cyclizing the diamides at 150 C for 2 hr under reduced pressure in a 92% yield. The crude imidazolines were purified by crystalliza-tion. The fatty imidazolines were readily hydrolyzed at the C=N bond of the imidazoline ring with water or dilute alcohol. The resulting diamides, RCON(CH2 CH2 NH2)CH2 CH2 NHCOR, were also purified by crystallization. Water repellency of these com-pounds was evaluated by contact angle measurements and percola-tion tests. The surface properties of these series of compounds are determined by four parameters. The open-chain diamides are more hydrophobic than the analogous imidazolines, and hydrophobicity increases with increasing molecular weight of derivatives of saturated fatty acids. Oleic acid derivatives are far more hydrophilic than the saturated acid derivatives or the analogous elaidic acid derivatives. The latter are more hydrophilic than stearic derivatives.