cssi/SciSciGPT-SciSciNet huggingface dataset:
Complete 1H and 13C assignments of ractopamine hydrochloride using 2D and selective 1D NMR methods

The 1 H and 13 C NMR resonances for ractopamine hydrochloride have been assigned. H,H-COSY and H,C-COSY were used to assign the aliphatic moiety of the molecule and to correlate protons and carbons on the same ring system. Long-range selective proton decoupling (LSPD) experiments were used to assign quaternary carbons and to distinguish the two ring systems
Real-time, ultrahigh-resolution, optical coherence tomography with an all-fiber, femtosecond fiber laser continuum at 1.5 µm

Real-time, ultrahigh-resolution optical coherence tomography (OCT) is demonstrated in the 1.4-1.7-microm wavelength region with a stretched-pulse, passively mode-locked, Er-doped fiber laser and highly nonlinear fiber. The fiber laser generates 100-mW, linearly chirped pulses at a 51-MHz repetition rate. The pulses are compressed and then coupled into a normally dispersive highly nonlinear fiber to generate a low-noise supercontinuum with a 180-nm FWHM bandwidth and 38 mW of output power. This light source is stable, compact, and broadband, permitting high-speed, real-time, high-resolution OCT imaging. In vivo high-speed OCT imaging of human skin with approximately 5.5-microm resolution and 99-dB sensitivity is demonstrated.
An Adaptive Acoustic Echo Canceler for Hands-Free Teleconferencing

Abstract Porayath, R., Doherty, J. F., and Russell, S. F., An Adaptive Acoustic Echo Canceler for Hands-Free Teleconferencing,Digital Signal Processing6(1996), 29–36. A new technique for high quality acoustic echo cancellation in teleconference and speaker phone systems has been developed. The new echo canceler is based on an enhanced adaptive filtering algorithm and uses a spread-spectrum-based technique to mitigate the effects of double talk. The test facility used to develop this new acoustic echo canceler and the system design of echo canceler are described.
Frente conjetural: escritores brasileños de izquierda y el Estado Novo

In the official newspaper of the Estado Novo , a dictatorship led by Getulio Vargas in Brazil from 1937 to 1945, a group of intellectuals organized a cultural section, «Pensamento da America», devoted to publishing translations of writers from across the Americas. Drawing on archival research, this article reconstructs the trajectory of this cultural section, from muted anti-fascism and Latin Americanism, in 1941, to playing a supporting role for Vargas’s wartime foreign policy, from 1942 on. It is concerned, above all, with exploring the contexts that both opened the way and set the limits for the activities of the intellectuals responsible for «Pensamento da America».
Money supply announcements, interest rates, and foreign exchange

Abstract This paper presents a test of the joint hypothesis that money supply announcements affect the real interest rate and that changes in the real interest rate affect the exchange rate in the short run. The test results are consistent with the joint hypothesis. For example, it is found that announcement of an unexpected jump in the money supply is accompanied by an increase in interest rates and an appreciation of the dollar. If the rise in interest rates was entirely due to higher inflationary expectations, the dollar should not appreciate.
ROC analysis of ATR from SAR images using a model-based recognizer incorporating pose information

An automatic taget recognition (ATR) technique developed by the authors features analytically derived object models which are formed from entire image suites, yet are compact and allow a direct target recognition and pose determination procedure. In contrast to the pose-invariant information used to form the models in conventional approaches, view-dependent information is retained in the formation of the compact models for this new approach. All model-based ATR systems are confronted with the problem of image variation as a function of viewing angle. This problem can be addressed by use of an exhaustive library of views, at the expense of a large suite of literal images and a computationally intensive search-based recognition process. Means for overcoming these storage and processing obstacles have traditionally invloved some type of view-independent target representation, often developed from some composite view of the target over the viewing angles of interest. This results in a much more compact target model, and a more direct recognition process. Unfortunately, the gains in storage and computational requirements of these invariant algorithms come at the price of diminished target discrimination capability. The new algorithm incorporates pose as a fundamental parameter which is solved for as part of the recognition process, and does not discard the pose-related information which is relevant to target recognition. In this paper, the newly developed technique is applied to synthetic aperture radar images to develop receiver operating characteristic curves in the presence of both multiplicative noise and clutter. Comparative curves are also developed for a conventional generalized quandratic classifier ATR system.
The rainbow range, British Columbia: A miocene peralkaline shield volcano

Abstract The Rainbow Range is a Late Miocene shield volcano (30 km diameter, 370 km 3 ) whose stratiform flanks surround a complex central zone. Over a 2-m.y. interval, extrusion of low viscosity, silicic peralkaline lavas and minor basaltic lavas built up the gently sloping (5–8°) flanks, forming a shield volcano rather than a composite cone. Comenditic trachytes are the lowest flows exposed on the north flank of the volcano. Thin mugearite flows rest unconformably on the comenditic trachytes. Comendites unconformably overlie the mugearites and account for at least 75% of the volume of flows within the flank zone. These lavas are distinguished from the comenditic trachytes by lower Al 2 O 3 (13%), higher total iron as Fe 2 O 3 , (7%), and extremely depleted Sr (1–10 ppm) and Ba (10–100 ppm). Strontium isotopic studies combined with petrologic data suggest that Rainbow Range lavas originated from alkali basalt magma trapped in an intracrustal magma chamber and tapped at several intervals after it underwent crystal fractionation. A best-fit mathematical model for the origin of the suite involves step-wise derivation of the lavas in the order hawaiite → mugeartite → comenditic trachyte → comendite, with the major phases precipitating in the order: olivine, clinopyroxene, plagioclase, iron-titanium oxides, and alkali feldspar.
The influence of temperature and depth dependent viscosity on geoid and topography profiles from models of mantle convection

Abstract We consider the geoid and topography profiles from convection models with depth and temperature-dependent viscosity models in a 2-D Cartesian geometry. We use a very low viscosity region in the top center of the geometry to generate plate-like viscosity models. We focus on subduction regions, which have narrow (100–200 km) trenches. The narrow trench is only a minor feature in the regional geoid. In depth-dependent viscosity models, we change the geometry of the weak zone around the ocean trench to study the impact of the weak zone on trench topography and the geoid. We also vary the vertical viscosity structure of the models. The weak zone geometry has very little effect on the surface velocity of the ocean plate or the large scale pattern of convection. The width of the weak zone, within a reasonable range, has little effect on topography and geoid profiles. There is a narrow trough in the geoid and topography profiles. This trough becomes wider and deeper with a high viscosity upper mantle. This may suggest that the high viscosity upper mantle is not suitable for our models. In temperature-dependent viscosity models, we vary the viscosity values for different layers. Temperature-dependent viscosity is also important to producing realistic subduction models; however, the activation energy must be weaker than laboratory estimates of olivine under mantle pressures and temperatures. From both depth and temperature-dependent viscosity models, the viscosity in the lower mantle should be at least ten times greater than in the upper mantle, consistent with previous studies of the geoid in regions of subduction. The topography and geoid profiles can match the observations when the viscosity increases with depth.
An Organizational Memory Approach to Information Management

We extend and adapt a model of group memory to organizations. Using this extended model, they identify information management challenges of the next century and suggest that organizations can address these challenges by locating a large portion of their information-processing activities outside their formal boundaries, by adopting novel socialization tactics, and by focusing on the management of soft knowledge forms (e.g., tacit knowledge, judgment, and intuitive abilities). Whereas current theories increasingly equate information management with the management of information technology, we argue that information technology needs to be complemented by organization-level processes related to organizational memory.
1,3,5-trichlorotricyanobenzene complexes with mesitylene (1/1) and benzene (1/3)

Trichlorotricyanobenzene-mesitylene (1/1) is monoclinic, space group P21/n; at −88°Ca=10.509(3),b=14.863(7),c=11.518(3) A, β=99.38(2)0,V=1775(2) A3,D x =1.409(2) g cm−3,Z=4. Trichlorotricyanobenzene-benzene (1/3) is hexagonal, space group $$P\bar 6$$ ; at −99°Ca=17.3914(3),c=7.2673(1) A,V=1903.6(1) A3,D x =1.2844(1) g cm−3,Z=3. In both complexes there are stacks of alternating trichlorotricyanobenzene and hydrocarbon molecules. In both complexes there are sheets of molecules perpendicular to the stacks. In the mesitylene complex these sheets contain equal numbers of both kinds of molecules with the trichlorotricyanobenzene molecules arranged in tapes. In the benzene complex the sheets contain only one kind of molecule or the other. The sheets containing the trichlorotricyanobenzene molecules have approximately linear C−N...Cl−C intermolecular interactions with N...Cl distances about 3.02 a.
Evolution of Broad Host Range in Retroviruses Leads to Cell Death Mediated by Highly Cytopathic Variants

The ability of many retroviruses to cause disease can be correlated to their cytopathic effect (CPE) in tissue culture characterized by an acute period of cell death and viral DNA accumulation. Here, we show that mutants of a subgroup B avian retrovirus (Alpharetrovirus) cause a very dramatic CPE in certain susceptible avian cells that is coincident with elevated levels of apoptosis, as measured by nuclear morphology, and persistent viral DNA accumulation. These mutants also have a broadly extended host range that includes rodent, cat, dog, monkey, and human cells (31). Previously, we have shown that the mutants exhibit diminished resistance to superinfection. The results presented here have important implications for the process of evolution of retroviruses to use distinct cellular receptors.
Rapid tau aggregation and delayed hippocampal neuronal death induced by persistent thrombin signaling

Tau hyperphosphorylation, leading to self-aggregation, is widely held to underlie the neurofibrillary degeneration found in Alzheimer's disease (AD) and other tauopathies. However, it is unclear exactly what environmental factors may trigger this pathogenetic tau hyperphosphorylation. From several perspectives, the coagulation serine protease, thrombin, has been implicated in AD and activates several different protein kinase pathways but has not previously been shown how it may contribute to AD pathogenesis. Here we report that nanomolar thrombin induced rapid tau hyperphosphorylation and aggregation in murine hippocampal neurons via protease-activated receptors, which was followed by delayed synaptophysin reduction and apoptotic neuronal death. Mechanistic study revealed that a persistent thrombin signaling via protease-activated receptor 4 and prolonged downstream p44/42 mitogenactivated protein kinase activation are at least in part responsible. These results pathogenetically linked thrombin to subpopulations of AD and other tauopathies associated with cerebrovascular damage. Such knowledge may be instrumental in transforming therapeutic paradigms.
KNOBBY ANALYSES OF KNOBLESS SURVEY ITEMS, PART II: AN APPLICATION

This is Part II of a new approach to survey studies called knobby analyses of knobless survey items. In Part II, this approach is applied to a study of the national sales organization of a large high‐technology firm called here Euphoria BioTechnology. A 17 item Employee Opinion Survey (EOS) was constructed and administered concurrently with an Organizational Diagnostic Survey (ODS). The EOS inquired about the main features and properties of the organization and the ODS, based on the theory of the organizational hologram, provided a series of knobs which were used to “explain” their variance. Knobby analyses involve moving beyond data expertise to expert data. Data expertise is employed in both the EOS and the ODS surveys. However, knobby analyses allow one to leverage the EOS results to improve the derivation of the conclusions or meanings of the results of the survey data and to reach recommendations. Furthermore, knobby analyses allow follow‐up analyses of special management problems. Four examples of t...
The metabolic source of the succinyl-CoA moiety of δ-aminolevulinic acid

Abstract Valine and isoleucine are shown to be readily incorporated into urinary ALA. Their specific incorporation is higher than that of precursors of succinyl-CoA generated via the tricarboxylic acid cycle. This suggests the possibility of two pools of succinyl-CoA within the mitochondrion. The role of branched-chain amino acid catabolism in heme synthesis is discussed.
Quantitative Computed Tomography in the Evaluation of Spinal Osteoporosis Following Spinal Cord Injury

Disuse osteoporosis occurs in the lower extremities of patients with spinal cord injury (SCI). However, spinal osteoporosis is not usually observed in these patients. We investigated lumbar spine bone mineral density (BMD) in SCI patients using single energy quantitative computed tomography (QCT) and dual-energy X-ray absorptiometry (DXA). Our study population consisted of 64 patients with long-standing SCI. Spine BMD (g/cm3) was assessed by QCT at four vertebrae ranging from T11 to L4 with single midvertebral CT slices 1 cm thick parallel to the vertebral end-plates. Confounding variables affecting normal trabecular bone pattern, such as compression fractures, surgical hardware or fat replacement, were excluded. For a subset of 29 patients, DXA values of the spine and femoral neck were also measured, and QCT and DXA Z-scores were compared On the average, the 64 SCI patients had Z-scores 2.0 ± 1.2 below those of age-matched controls. In the subset of 29 patients with both QCT and DXA measurements, the QCT and DXA Z-scores were 2.4 ± 1.1 below and 1.3 ± 2.3 above the mean, respectively (p<0.0001). Our results indicate that QCT reveals osteoporosis of the spine after SCI, in contrast to DXA. We postulate that QCT is more valuable for evaluating spinal osteoporosis following SCI than DXA and thus recommend QCT for spinal BMD studies in SCI.
Increased patient concern after false-positive mammograms: clinician documentation and subsequent ambulatory visits.

OBJECTIVE: To measure how often a breast-related concern was documented in medical records after screening mammography according to the mammogram result (normal, or truenegative vs false-positive) and to measure changes in health care utilization in the year after the mammogram.
Cumulative Versus Continuous Disadvantage in an Unstructured Labor Market: Gender Differences in the Careers of Television Writers

This article uses longitudinal career history data for the period 1982 through 1990 to explore the mechanisms that produce a gender gap in earnings among writers in the television industry. Two models of labor market dynamics are compared. The first is a model of cumulative disadvantage whereby differential access to opportunity is increasingly consequential over the course of writers' careers. The second is a model of continuous disadvantage whereby the contributions of women writers are uniformly devalued across career stages. The results strongly support the model of continuous disadvantage and show that a narrowing of the wage gap is limited to very recent cohorts of writers. The article describes how unstructured labor market arrangements in the entertainment industry sustain the process of continuous disadvantage and discusses implications for labor market issues more generally.
Acute conversion of persistent atrial fibrillation during dofetilide loading does not predict long-term atrial fibrillation-free survival

Pharmacologic conversion of atrial fibrillation and flutter (AF/AFl) is common with dofetilide. We determined whether pharmacologic conversion with dofetilide predicts long-term arrhythmia-free survival. We retrospectively studied a cohort of 264 consecutive patients who initiated dofetilide during persistent AF/AFl between 2008 and 2013. Patients were excluded if dofetilide was discontinued prior to five doses or electrical cardioversion was performed prior to four doses. Incidence of and characteristics associated with pharmacologic conversion were determined. Patients were followed for long-term AF/AFl recurrence. Predictors of recurrence were identified using multivariate Cox modeling. Of 205 patients meeting study criteria, 92 (44.9 %) converted to sinus rhythm during dofetilide loading. Female gender, history of AFl, greater number of prior catheter ablations, shorter duration of current AF/AFl, and presentation in AFl were all associated with acute pharmacologic conversion (p = 0.001, 0.05, 0.001, 0.003, and 0.003, respectively). In multivariate modeling, longer time since first AF/AFl diagnosis (hazard ratio (HR) = 1.07 per 1-year increase, 95 % confidence interval (CI) 1.03–1.10, p < 0.001), longer duration of current AF/AFl episode (HR = 1.01 per 1-month increase, 95 % CI 1.00–1.01, p = 0.003) and greater number of failed antiarrhythmic drugs (HR = 1.43 per one drug increase, 95 % CI 1.20–1.70, p < 0.001) were independently associated with shorter time to AF/AFl recurrence. Pharmacologic conversion was not significantly associated with time to AF/AFl recurrence (HR = 0.79, 95 % CI 0.57–1.10, p = 0.2). Acute pharmacologic conversion of persistent AF/AFl to sinus rhythm frequently occurs during dofetilide loading. Nevertheless, acute pharmacologic conversion does not predict long-term arrhythmia control, which was moderate at best.
Ascariasis infection of the colon: MDCT evaluation

Ascariasis is the most common helminth infection in the world and is a common cause of abdominal symptoms worldwide. Although rare in the United States, isolated cases do occur in the Southwestern States. We present a case of a 34-year-old woman who presented to the emergency room with abdominal pain and diarrhea. The diagnosis of ascariasis was made on CT scan.
Correlation between the anaesthetic effect of halothane and saturable binding in brain.

Two theories of the molecular mechanism of volatile anaesthetic action suggest either that anaesthetics cause a generalized perturbation of neuronal membrane structure, probably through a nonspecific interaction with membrane lipids1,2, or that anaesthetics bind to sets of sites of appropriate molecular dimension on membrane proteins3–5. Based on the recent finding that fluorinated anaesthetics can be observed in animal tissue by 19F nuclear magnetic resonance (19F-NMR) spectroscopy6, we have used 19F-NMR to quantify the interaction between the volatile anaesthetic halothane and rat brain tissue. Steady-state brain halothane concentration was found to be a non-linear function of inspired concentration, with apparent saturation of brain occurring at inspired halothane concentrations above 2.5% by volume. Using a spin-echo pulse sequence it was found that halothane exists in two distinct chemical environments in brain, characterized by different spin-spin –relaxation times (T2), chemical shifts and kinetics of occupancy. Halothane concentration in one of these environments (T2=3.6ms) was saturated at ∼2.5% inspired halothane; occupancy of this environment was found to correlate with the anaesthetic effect of the drug. In the other environment (T2=43 ms), brain halothane concentration was a linear function of inspired concentration. These data suggest the existence of a saturable anaesthetic site for halothane in brain and do not support the concept that anaesthetics act by nonspecific membrane perturbation.
Milk Thistle and Its Derivative Compounds: A Review of Opportunities for Treatment of Liver Disease

Milk thistle extracts have been used as a “liver tonic” for centuries. In recent years, silibinin, the active ingredient in milk thistle extracts, has been studied both in vitro and in vivo to evaluate the beneficial effects in hepatic disease. Silibinin increases antioxidant concentrations and improves outcomes in hepatic diseases resulting from oxidant injury. Silibinin treatment has been associated with protection against hepatic toxins, and also has resulted in decreased hepatic inflammation and fibrosis. Limited information currently is available regarding silibinin use in veterinary medicine. Future study is justified to evaluate dose, kinetics, and treatment effects in domestic animals.
The Effect of Data Collection Technique on Estimated Landowner Personal Network Attributes

Social network analysis, focusing on the role of interpersonal relationships on the flow of information, trust, and service delivery, is increasingly recognized as a valuable approach to understanding landowner behavior. Landowner personal networks are central to Diffusion of Innovations theory and the Theory of Planned Behavior, both of which are commonly invoked in the design of interventions to encourage sustainable private forest management. However, personal network data can be difficult to obtain for a large sample. We tested the effect of three different personal network name generators on estimates of Minnesota landowners’ forestry information networks: a list of generic alter categories, an open-ended written survey, and a combination of written survey and follow-up telephone survey. Generic network data provided a relatively accurate baseline. Personal network data from a written survey provided more detailed data but underestimated network diversity and failed to account for potentially influential weak ties. A combination of written and follow-up telephone survey both doubled estimated average network size from 2.8 to 5.5 alters and increased estimated network diversity from 2.3 alter categories per respondent to 3.7. Network data from the written survey revealed a bias in favor of strong ties that was largely overcome through additional prompting during the telephone survey. A combination of written surveys and telephone or in-person interviews may be the best strategy to balance the benefit of a large sample with the cost of more intensive, yet more reliable, data collection methods.
OPTIMAL S-N TESTING FOR VARIABLE-AMPLITUDE FATIGUE APPLICATIONS

A new methodology is developed that can identify the optimal testing procedure to be used in generating S-N curves for predicting damage accumulation under variable-amplitude service loads. This is a significant extension of existing knowledge, which includes a solution to this problem only for situations in which the service loads are constant amplitude. The methodology has the potential to improve significantly the predictions of fatigue damage and reliability under realistic service loads. In general, finding the truly optimal solution involves solving a quartic equation, but it is often possible to use a simplified form that involves only a quadratic equation. The new results are identical to the previously developed formulation for the special situation of a constant-amplitude service load. The information needed to use the general procedure is the distribution of stress amplitudes in the service load and the variability of the service life among identical load/specimen combinations. The procedure is illustrated here by its application to the special case of bilevel service loads, for which numerical results are presented. This includes information on both the optimal S-N testing procedure, and the sensitivity of the mean-squared error to changes in the testing procedure.
The order of visual processing: "Top-down," "bottom-up," or "middle-out"

This paper deals with the order in which different levels of form are recognized in a visual image. An experiment is reported in which the size of a tachistoscopically viewed image was varied. The results suggest neither an invariant “top-down” (gross shapes first followed by lower-order details) or “bottom-up” (the opposite) sequence. Rather, they seem to suggest a sort of “middle-out” sequence: forms at some intermediate level of structure having an optimal size or spatial-frequency spectrum are processed first, with subsequent processing of both higher and lower levels of form.
Review of Data Analysis With MPlus, by Christian Geiser

In Data Analysis With Mplus, Christian Geiser has provided an easy-to-follow beginners’ guide to using the Mplus statistical software (Muthen & Muthen, 1998–2004) for analysis of multivariate data....
Orientation columns in the mouse superior colliculus

More than twenty types of retinal ganglion cells conduct visual information from the eye to the rest of the brain. Each retinal ganglion cell type tessellates the retina in a regular mosaic, so that every point in visual space is processed for visual primitives such as contrast and motion. This information flows to two principal brain centres: the visual cortex and the superior colliculus. The superior colliculus plays an evolutionarily conserved role in visual behaviours, but its functional architecture is poorly understood. Here we report on population recordings of visual responses from neurons in the mouse superior colliculus. Many neurons respond preferentially to lines of a certain orientation or movement axis. We show that cells with similar orientation preferences form large patches that span the vertical thickness of the retinorecipient layers. This organization is strikingly different from the randomly interspersed orientation preferences in the mouse’s visual cortex; instead, it resembles the orientation columns observed in the visual cortices of large mammals. Notably, adjacent superior colliculus orientation columns have only limited receptive field overlap. This is in contrast to the organization of visual cortex, where each point in the visual field activates neurons with all preferred orientations. Instead, the superior colliculus favours specific contour orientations within ~30° regions of the visual field, a finding with implications for behavioural responses mediated by this brain centre.
Clinical Decision Making—-A Functional Medicine Perspective

As 21st century health care moves from a disease-based approach to a more patient-centric system that can address biochemical individuality to improve health and function, clinical decision making becomes more complex. Accentuating the problem is the lack of a clear standard for this more complex functional medicine approach. While there is relatively broad agreement in Western medicine for what constitutes competent assessment of disease and identification of related treatment approaches, the complex functional medicine model posits multiple and individualized diagnostic and therapeutic approaches, most or many of which have reasonable underlying science and principles, but which have not been rigorously tested in a research or clinical setting. This has led to non-rigorous thinking and sometimes to uncritical acceptance of both poorly documented diagnostic procedures and ineffective therapies, resulting in less than optimal clinical care.
Reflectivity Spectrum and Optical Constants of Bituminous Coal; Estimation of Aromaticity

The spectra of reflectivities, refractive indices, and absorption indices of a bituminous coal vitrain have been determined for the ultraviolet-visible spectral region. The low values for these quantities support the premise that polynuclear condensed aromatics may be present in coal only in small amounts. Aliphatic and amorphous carbons may predominate. suggested for glass ( 6 ).
The follicular placenta of the viviparous fish, Heterandria formosa. I. Ultrastructure and development of the embryonic absorptive surface.

Embryos of the poeciliid Heterandria formosa develop to term in the ovarian follicle in which they establish a placental association with the follicle wall (follicular placenta) and undergo a 3,900% increase in embryonic dry weight. This study does not confirm the belief that the embryonic component of the follicular placenta is formed only by the surfaces of the pericardial and yolk sacs; early in development the entire embryonic surface functions in absorption. The pericardial sac expands to form a hood-like structure that covers the head of the embryo and together with the yolk sac is extensively vascularized by a portal plexus derived from the vitelline circulation. The hood-like pericardial sac is considered to be a pericardial amnion-serosa. Scanning and transmission electron microscopy reveal that during the early and middle phases of development (Tavolga's stages 10-18 for Xiphophorus maculatus) the entire embryo is covered by a bilaminar epithelium whose apical surface is characterized by numerous, elongate microvilli and coated pits and vesicles. Electron-lucent vesicles in the apical cytoplasm appear to be endosomes while a heterogeneous group of dense-staining vesicles display many features characteristic of lysosomes. As in the larvae of other teleosts, cells resembling chloride cells are also present in the surface epithelium. Endothelial cells of the portal plexus lie directly beneath the surface epithelium of the pericardial and yolk sacs and possess numerous transcytotic vesicles. The microvillous surface epithelium becomes restricted to the pericardial and yolk sacs late in development when elsewhere on the embryo the non-absorptive epidermis differentiates. We postulate that before the definitive epidermis differentiates, the entire embryonic surface constitutes the embryonic component of the follicular placenta. The absorptive surface epithelium appears to be the principle embryonic adaptation for maternal-embryonic nutrient uptake in H. formosa, suggesting that a change in the normal differentiation of the surface epithelium was of primary importance to the acquisition of matrotrophy in this species. In other species of viviparous poeciliid fishes in which there is little or no transfer of maternal nutrients, the embryonic surface epithelium is of the non-absorptive type.
Maximizing Information from a Water Quality Monitoring Network through Visualization Techniques

This paper describes a variety of visualization techniques that have been very useful for demonstrating important aspects of a water quality monitoring programme in South Florida. The first level of visualization was at the single station or grouped stations using the box-and-whisker plot as a graphical/statistical tool. This plot was used to compare intra-annual variability and correlation between total phosphorus (TP) and chlorophyll a (chl a) at a site in Florida Bay. Secondly, time was added as a dimension to produce a 9-year, monthly time series plot of declining salinity at a site in NE Florida Bay. It was shown how a centred moving average could be used to smooth out the noise and disclose inter-annual oscillations. Time series of anomalies from long term means were discussed as a means of displaying correspondence and coupling among variables. Thirdly, the utility of 2-D contour maps of variables was demonstrated in showing sources and mixing of fresh water across the hydroscape as well as nutrient loading to the South Florida ecosystem. From this expanded spatial view, it was observed that the water quality of different bays and coastal areas are differentially affected both by external and internal processes and how management of pump operations and canal conductance can overwhelm the natural hydrological cycle and have far reaching impacts in Florida Bay and the SW Florida Shelf. We also showed that contouring was useful for elucidating causal relationships among variables over the spatial domain. Time step animations of monthly salinity contours in Florida Bay showed the importance of mixing with western boundary waters to alleviation of hypersaline conditions. These animations also showed that it is the shifting lags between TP concentration and chl a which make it so difficult to derive a simple regression model. Finally, a 3-D volumetric rendering of the area between Key West and the Tortugas was used to describe a strong density stratification event during July 1998 and to visualize the source of water masses and general circulation patterns in this region. It is concluded that visualization techniques are useful not only to show patterns in the data but in developing new hypotheses for future research and monitoring activities.
URINARY EXCRETION OF PHENETHYLAMINE AND TYRAMINE IN NORMAL SUBJECTS AND HETEROZYGOUS CARRIERS OF PHENYLKETONURIA.

Abstract Heterozygous carriers of phenylketonuria were found to differ from normal subjects in that they tended to excrete more phenethylamine and less tyramine in the urine; these differences were more pronounced after a phenylalanine load. The differences were not sufficiently consistent to form the basis of an improved technique for differentiating heterozygotes from normals. This is apparently the first report of urinary excretion of phenethylamine in normal human subjects.
Approximate solution of linearized ballistic equation of motion witherror analysis.

An approximate solution of the linearized equation of motion of a sounding rocket is presented which will give a closed-form solution in terms of elementary functions for the complex yaw angle as a function of density ratio or altitude. A method for determining the error in the approximation is presented which applies to all cases. The error is shown to be a function of a complex parameter which is simply computed from the aerodynamic and gyroscopic inputs. The error for the entire range of the parameter is given by an asymptotic equation and graphical results.
Response of the cell membrane-cytoskeleton complex to osmotic and freeze/thaw stresses. Part 2: The link between the state of the membrane-cytoskeleton complex and the cellular damage.

Abstract In an earlier paper [35] , we examined the mutual interaction between the actin cytoskeleton and the cell membrane and explored the role this interaction plays during freeze/thaw. In this follow-up paper, we investigate the physical and chemical stresses induced by freeze/thaw and explore the different mechanisms of damage caused by these stresses. Our results showed that changes in cell volume during freeze/thaw and the unfrozen water content in the solution alter the cytoskeleton stiffness, and the available membrane material. Combined with unfavorable ice–membrane interactions and increasing membrane stiffness, increased de-structuring of the membrane (such as bleb and microvilli formation) synergistically act on the membrane–cytoskeleton system generating irreversible damage.
MnO/TiO2/P2O5: a minor element discriminant for basaltic rocks of oceanic environments and its implications for petrogenesis

Abstract A ternary diagram using MnO, TiO 2 , P 2 O 5 can discriminate between five petrotectonic environments of basaltic rocks (45–54% SiO 2 ). Fields for mid-ocean ridge, island arc tholeiite, island arc calc-alkaline, ocean island tholeiite, and ocean island alkalic rocks were distinguished on the basis of 507 analyses from well-defined environments. Boninites plot within island arc fields. Continental tholeiites, such as the Columbia River basalts, are high in P 2 O 5 relative to MnO and TiO 2 , and overlap portions of all five oceanic fields. MnO is depleted relative to TiO 2 in mid-ocean ridge analyses and may be controlled by early fractionation of olivine and/or clinopyroxene under conditions of low f O 2 . In island arc rocks, MnO is enriched relative to TiO 2 due to early crystallization of titanomagnetite in a high- f O 2 environment. Primitive mid-ocean ridge and arc tholeiites have similar MnO/TiO 2 /P 2 O 5 ratios which indicate a grossly similar parent magma. Increasingly differentiated basaltic rocks are more easily classified by the diagram. High relative abundances of TiO 2 and P 2 O 5 in ocean island rocks are consistent with their derivation from a separate source. Despite the purported high mobility of MnO, the MnO/TiO 2 /P 2 O 5 discriminant diagram may be applied to unspilitized and moderately spilitized zeolite to greenschist facies greenstones with good agreement between the environment determined by MnO/TiO 2 /P 2 O 5 and by other means such as trace elements, REE, or field relations.
Single-change circular covering designs

Abstract A single-change circular covering design (scccd) based on the set [ v ] = {1,…, v } with block size k is an ordered collection of b blocks, B = {B 1 ,…,B b } , each B i ⊂ [ v ], which obey: (1) each block differs from the previous block by a single element, as does the last from the first, and, (2) every pair of [ v ] is covered by some block. The object is to minimize b for a fixed r and k . We present some minimal constructions of scccds for arbitrary v when k − 2 and 3, and for arbitrary k when k + 1 ⩽ v ⩽ 2 k . Tight designs are those in which each pair is covered exactly once. Start-Finish arrays are used to construct tight designs when v > 2 k ; there are 2 non-isomorphic tight designs with ( v , k ) = (9, 4), and 12 with ( v , k ) = (10, 4). Some non-existence results for tight designs, and standardized, element-regular, perfect, and column-regular designs are considered.
Mixed reality for unmanned aerial vehicle operations in near Earth environments

Future applications will bring unmanned aerial vehicles (UAVs) to near Earth environments such as urban areas, causing a change in the way UAVs are currently operated. Of concern is that UAV accidents still occur at a much higher rate than the accident rate for commercial airliners. A number of these accidents can be attributed to a UAV pilot's low situation awareness (SA) due to the limitations of UAV operating interfaces. The main limitation is the physical separation between the vehicle and the pilot. This eliminates any motion and exteroceptive sensory feedback to the pilot. These limitation on top of a small field of view from the onboard camera results in low SA, making near Earth operations difficult and dangerous. Autonomy has been proposed as a solution for near Earth tasks but state of the art artificial intelligence still requires very structured and well defined goals to allow safe autonomous operations. Therefore, there is a need to better train pilots to operate UAVs in near Earth environments and to augment their performance for increased safety and minimization of accidents.
Cosmic-Ray-Induced Ship-Effect Neutron Measurements and Implications for Cargo Scanning at Borders

Abstract Neutron measurements are used as part of the interdiction process for illicit nuclear materials at border crossings. Even though the natural neutron background is small, its variation can impact the sensitivity of detection systems. The natural background of neutrons that is observed in monitoring instruments arises almost entirely from cosmic-ray-induced cascades in the atmosphere and the surrounding environment. One significant source of variation in the observed neutron background is produced by the “ship effect” in large quantities of cargo that transit past detection instruments. This paper reports on results from measurements with typical monitoring equipment of ship effect neutrons in various materials. One new result is the “neutron shadow shielding” effect seen with some low neutron density materials.
Microcantilever Sensing and Actuation with End-Grafted Stimulus-Responsive Elastin-Like Polypeptides†

Stimulus-responsive elastin-like polypeptides (ELPs) grafted onto surfaces are of significant technical interest because they can be exploited for force generation, in sensing applications, or as molecular switches with tunable properties. Changes in the conformational state of grafted ELPs, induced by a phase transition or changes in osmotic pressure, lead to significant changes in the surface stress in the ELP graft layer and translate into detectable changes in microcantilever deflection. In this study, we investigate the conformational mechanics of ELPs in response to changes in solution pH and ionic strength using atomic force microscopy (AFM) microcantilever deflection and quartz crystal microbalance (QCM) measurements. We show that the use of genetically encoded, surface-grafted ELPs is exciting for cantilever actuation and sensing because commonly available microfabricated cantilever springs offer a simple and nonintrusive way to detect changes in solvent type, temperature, and pH, promising great potential for sensing applications in microfluidic devices.
ANALYSIS OF DATA FROM AN ADMISSIONS TEST WITH ITEM MODELS

Item models (LaDuca, Staples, Templeton, & Holzman, 1986) are classes from which it is possible to generate/produce items that are equivalent/isomorphic to other items from the same model (e.g., Bejar, 1996; Bejar, 2002). They have the potential to produce large number of high-quality items at reduced cost. This paper introduces data from the first known application of items automatically generated from item models in a large-scale assessment and deals with several research questions associated with the data. We begin by reviewing calibration techniques for the analysis of data involving item models; one method assumes that the items are isomorphic, while the other treats items generated from the same item model as distinct, but related. A major question for these type of data is whether these items are isomorphic, that is, if they behave the same psychometrically. This paper describes a number of rough diagnostic measures and a rigorous statistical diagnostic to assess the extent of isomorphicity in the items generated from an item model. Finally, this paper discusses the issue of scoring, an area that needs more research, with data involving item models.
Dynamic trading value at risk: Futures floor trading

Speculative traders' dynamic trading strategies are not easy to model, because they depend on latent information flows and preferences. As a result, the risks involved in such strategies may only be revealed by examining empirical distributions of ex post returns to traders engaged in speculative activities. The authors' comprehensive data from futures floor trader's proprietary trading allows for an empirical examination of one prominent type of speculative trader risk. It is shown that floor trader “value at risk” can be predicted somewhat, using simple market variables such as volume and volatility. Although some predictability for the crosssectional distribution of floor trader income, and hence risk was found, not much was determined in terms of trader-specific characteristics. © 2006 Wiley Periodicals, Inc. Jrl Fut Mark 26:1217–1234, 2006
Single-Molecule Recreation of the Cadherin/Catenin/Actin Complex

Adherens junctions (AJs) comprise protein complexes essential for integrating cell-cell adhesion and actin cytoskeleton functions, and their importance has been shown in many loss-of-function studies. Disruption of acto-myosin tension in living cells impairs formation of AJs, but attempts to reconstitute in bulk assays a direct linkage between a minimal AJ complex (E-cadherin/β-catenin/α-catenin) and actin filaments in vitro have been unsuccessful. Here we present a new optical trap-based single-molecule assay that tests whether this linkage requires tension (Fig. 1A). using a reconstituted E-cadherin/β-catenin/α-catenin complex (∼100 nM), an actin filament held between 2 optical traps, and moving the complex along the actin filament by oscillating the microscope stage, we observe binding events that likely involve multiple complexes and displacements of over 100 nm with loading rates of ∼45 pN/s that can sustain over 15 pN of force. The stepwise release mechanism may reflect sequential detachment of individual E-cadherin/catenin complexes (Fig. 1B). These data indicate that several E-cadherin/catenin complexes can form a robust, load-resistant connection to an actin filament under tension. In ongoing work, we are studying how mechanical load may regulate the affinity between the E-cadherin/catenin complexes and actin filaments.View Large Image | View Hi-Res Image | Download PowerPoint Slide
The millimeter wavelength spectrum of diatomic sulfur

Abstract The gas phase spectrum of diatomic sulfur has been detected in the millimeter wave-length region. Six lines have been measured. The rotational and fine structure parameters obtained are B 0 = 8831.8676 ± 0.006 MHz, D 0 = 5.9 ± 0.7 kHz, λ 0 = 353040 ± 27 MHz, and γ 0 = − 200.9 ± 0.7 MHz. In addition, reanalysis of EPR data has yielded g z + 1.18 g n = 2.0021 + 0.0014 and g z - g ⊥ = −0.0089 ± 0.0017. On the basis of the frequencies obtained in this work, it was also possible to exclude the assignment of several interstellar emissions to the sulfur dimer.
Identification of the angiogenesis signaling domain in pleiotrophin defines a mechanism of the angiogenic switch

Neoplasms progress through genetic and epigenetic mutations that deregulate pathways in the malignant cell that stimulate more aggressive growth of the malignant cell itself and/or remodel the tumor microenvironment to support the developing tumor mass. The appearance of new blood vessels in malignant tumors is known as the "angiogenic switch." The angiogenic switch triggers a stage of rapid tumor growth supported by extensive tumor angiogenesis and a more aggressive tumor phenotype and its onset is a poor prognostic indicator for host survival. Identification of the factors that stimulate the angiogenic switch thus is of high importance. Pleiotrophin (PTN the protein, Ptn the gene) is an angiogenic factor and the Ptn gene has been found to be constitutively expressed in many human tumors of different cell types. These studies use a nude mouse model to test if Ptn constitutively expressed in premalignant cells is sufficient to trigger an angiogenic switch in vivo. We introduced an ectopic Ptn gene into "premalignant" SW-13 cells and analyzed the phenotype of SW-13 Ptn cell tumor implants in the flanks of nude mice. SW-13 Ptn cell subcutaneous tumor implants grew very rapidly and had a striking increase in the density of new blood vessels compared to the SW-13 cell tumor implants, suggesting that constitutive PTN signaling in the premalignant SW-13 cell implants in the nude mouse recapitulates fully the angiogenic switch. It was found also that ectopic expression of the C-terminal domain of PTN in SW-13 cell implants was equally effective in initiating an angiogenic switch as the full-length PTN whereas implants of SW-13 cells in nude mice that express the N-terminal domain of PTN grew rapidly but failed to develop tumor angiogenesis. The data suggest the possibility that mutations that activate Ptn in premalignant cells are sufficient to stimulate an angiogenic switch in vivo and, since these mutations are frequently found in human malignancies, that constitutive PTN signaling may be an important contributor to progression of human tumors. The data also suggest that the C-terminal and the N-terminal domains of PTN equally initiate switches in premalignant cells to cells of a more aggressive tumor phenotype but the separate domains of PTN signal different mechanisms and perhaps signal through activation of a separate receptor-like protein.