cssi/SciSciGPT-SciSciNet huggingface dataset:
The role of a critical excitation length scale in dynamics of reentrant cardiac arrhythmias

We discuss computer simulations of one- and two-dimensional excitation waves corresponding to normal and abnormal rhythms in a model of myocardium. Our studies are aimed at finding the major physiologic parameters governing such transient processes as the formation of a reentrant wave and its subsequent degradation into the malignant cardiac arrhythmia – ventricular fibrillation. Our results demonstrate that in both the one- and two-dimensional cases the stability of a periodic process (representing a regular or VT rhythm) is determined by the same two physiologic parameters: the wavewidth \(\), which is approximately is the width of depolarized zone, and ratio of \(\) to the critical length \(\), which is defined as the wavewidth of an action potential propagating with the minimum possible speed. The amazing feature of general excitable medium is that these two numbers play predominate role in determining the behavior of the system. The parameter \(\) determines the length scale (size) of an ectopic region that may initiate a wave. It also determines the duration of the vulnerable window for initiating the unidirectional block as well as a minimum permissible length of the reentrant circuit. In two dimensions the relation between the diameter of the spiral core and the value of \(\) determines the pattern of spiral tip motion (near circular versus meandering) as it represents the outcome of the balance between electrical sources from depolarizing membrane and the electrical sinks (diffusive, i.e. Ohmic fluxes). This balance controls in a similar way two important electrophysiologic processes, the separation of a spiral tip from unexcitable obstacle (scar tissue) and the transition to meandering of the spiral tip in the homogeneous 2D medium. We also present some evidence that depending on the value of \(\) the waveforms of the simulated ECGs for reentrant activity vary from monomorphic to polymorphic.
Glucose Can Fuel Glutamate Uptake in Ischemic Brain

Astrocytes in culture can maintain glutamate uptake during hypoxia if glucose is available. To determine whether this capacity is shared by brain in situ, extracellular glutamate levels were measur...
Experimental validation of Monte Carlo dose calculations about a high‐intensity Ir‐192 source for pulsed dose‐rate brachytherapy

Despite widespread use of high‐intensity Ir‐192 remotely afterloaded sources, no published measured or calculated dose‐rate tables for currently used source designs are available. For a pulsed dose‐rate Ir‐192 source, both transverse axis (0.5–10 cm) and two‐dimensional polar dose‐rate profiles (1.5, 3, and 5 cm) were measured with thermoluminescent dosimetry in a solid water phantom. Dose rates were normalized to measured air‐kerma strength, and the source geometry was verified by pinhole autoradiography and transmission radiography. At each measurement point, dose rates were calculated by a Monte Carlo photon transport (MCPT) code, which realistically modeled the experimental phantom, source, and detector geometry. Agreement between MCPT absolute dose‐rate calculations and measurements averaged 3% and was less than 5%, demonstrating that Monte Carlo simulation is an accurate and powerful tool for two‐dimensional dosimetric characterization of high activity Ir‐192 sources.
Area-based socio-economic disadvantage and tuberculosis incidence.

OBJECTIVE: To examine neighborhood-level influences on tuberculosis (TB) incidence in a multilevel population-based sample. DESIGN: All incident TB cases in Washington State, United States (n = 2161), reported between 1 January 2000 and 31 December 2008 were identified. Multivariate Poisson analysis was used at the ZIP Code™ tabulation area (ZCTA) level, which allowed for further exploration of area-specific influences on TB incidence. RESULTS: A significant association was found between indices of socio-economic position (SEP) and TB incidence in Washington State, with a clear gradient of higher rates observed among lower ZCTA socio-economic quartiles. Compared to the wealthiest SEP quartile, the relative incidence of TB in successively lower quartiles was respectively 2.7, 4.1 and 10.4 (P trend <0.001). In multivariate analyses, the addition of area-level race, ethnicity and country of birth significantly attenuated this association (adjusted incidence rate ratios 2.3, 2.6, 5.7; P trend <0.001). CONCLUSION: This study found a significant inverse association between area measures of socio-economic status (SES) and TB incidence across ZCTAs in Washington State, even after adjusting for individual age and sex and area-based race, ethnicity and foreign birth. These results emphasize the importance of neighborhood context and the need to target prevention efforts to low-SES neighborhoods.
Contamination of commercially available intermediates of the glycolytic pathway

Die Prufung von kommerziell erhaltlichen glykolytischen Substraten auf Verunreinigung mit anderen Verbindungen der Glykolyse ergibt eine bis zu 4.55% betragende Kontamination von 2,3-DPG mit 3-PGA. In den untersuchten 2,3-DPG Chargen findet sich ausserdem eine Kontamination mit 2-PGA und PEP. Weitere bemerkenswerte Verunreinigungen konnen in F6P, FDP, 3-PGA und 2-PGA nachgewiesen werden.
Mechanism of Tonb-Dependent Outer Membrane Transporters in E. Coli Mini-Cells and Outer Membrane Vesicles

Current mechanistic models of the bacterial outer membrane TonB-dependent transporters (TBDT) suggest that transport is driven by the proton motive force (pmf) via interactions with the cytoplasmic membrane proteins TonB/ExbB/ExbD. Studies of these systems are challenging because of the lack of an in vitro reconstituted system, and transport must be studied in whole cells, which greatly limits biochemical and spectroscopic approaches. Use of evolved tRNA-tRNA synthetase pairs (Young et al.) along with orthogonal chemistry for specific placement of labels at non-sense mutations allows incorporation of labels in vivo. To enhance the specificity of the labeling, we developed the use of E. coli minicells that lack the chromosome but contain multi-copy plasmids. Only plasmid-encoded proteins are produced in minicells after separation from the mother cell and higher specificity of labeling is achieved. Moreover, minicells have the native arrangement and components of both membranes and periplasm, and physiological measurements can be made such as pmf-dependent uptake of vitamin B12 through the TBDT BtuB.To study properties of the outer membrane transporter in the absence of the inner membrane, naturally occurring outer membrane vesicles (OMVs) (Schwechheimer et al.) are amenable for transport and spectroscopic studies. Both sides of the OMV membrane are accessible to labels and spectroscopic probes are incorporated into cysteines in over-expressed outer membrane proteins with high specificity. This work is supported by NIH/NIGMS grant U54 GM087519.References:Young, T. S., Ahmad, I., Yin, J. A. and Schultz, P. G. (2009) J. Mol. Biol. 395, 361-374.Schwechheimer, C., Sullivan, C. J. and Kuehn, M. J. (2013) Biochemistry 52, 3031-3040.
Nonlinear control charts for jump detection

This paper presents a new class of nonlinear control charts which respond quickly to small shifts and jump patterns in tme series. The underlying disturbance models for the control charts are nonlinear extensions of the IMA(1,1) model. The Kalman filtering algorithm generates Bayesian estimates of the process level for the control chart plotting. The single-parameter chart is identical to the EWMA, while the two- and three-parameter designs are much more effective in detecting small shifts mixed with local trends. The nonlinear control charting scheme is also capable of detecting a mean shift in independent observation.
Soft magnetic thin-film memory materials

Thin-film deposition techniques as applied to magnetic memory applications are reviewed. The relationship between the microstructure of the film and the fabrication technique and pertinent parameters is discussed in terms of the atomistics of film nucleation and growth. The dependence of the magnetic properties governing switching of a magnetic storage element is qualitatively discussed in terms of the microstructure and ripple theory; literature data is used to elucidate this by showing the effects of composition, temperature, thickness, and substrate morphology on the magnetic properties. The literature values for the anisotropy field, coercivity field, and dispersion of various classes of ternary alloys is reviewed, extending previous papers reviewing elemental and binary alloys.
Utilizing the Integral Technique for Obtaining a New Dimensionless Group for Prandtl Number Dependence for Natural Convection Heat Transfer From an Isothermal Vertical Flat Plate

Research is presented in this paper where the integral technique is utilized to find a primary dimensionless group for natural convection heat transfer from an isothermal vertical flat plate. The discovery of this group from fundamental principles demonstrates the value of the chronologically mature integral technique even in this advanced era where numerical techniques are much more prevalent. The integral solution in the current research compares very favorably with experimental data for a wide range of Prandtl numbers, and also with several numerical models in the archival literature as well as empirical correlations. The good agreement, coupled with the closed-form nature of the solutions, should once again affirm the usefulness of the integral technique as a research as well as an educational tool. The result of the research in this paper is the discovery of a fundamental parameter for Prandtl number dependence in the case of natural convection from an isothermal flat plate. With this fundamental parameter, the Prandtl number dependence is effectively linearized over the entire range of data available, and a simple empirical correlation derived, whose general form may be used for other geometries.Copyright © 2004 by ASME
The optimization of single-purpose reservoir design with the application of dynamic programming to synthetic hydrology samples

Abstract A method is developed for determining the optimal size of a single purpose reservoir to provide carryover storage for consumptive use on a stream where inflows in successive years may be serially correlated. The operating policy on an annual basis is obtained as a consequence of the analysis. The procedure combines dynamic programming sequenced over time, with different return functions for each interval of time, with a Monte Carlo technique using a number of equally likely sample sequences of inflow drawn randomly from a long synthetically generated period of record. The analysis gives an optimum operating policy, the expected value of the optimal return and the degree of risk involved which arises from the hydrologic characteristics of the stream.
Extraction and Assay of Lactogenic Hormone in Postpartum Urine12

THE USE OF LACTOGENIC AND PITUITARY extracts in man and animals for the purpose of increasing the level of milk secretion has been reported by a number of investigators. The reports on the whole have been encouraging, although a few negative results have been obtained in clinical trials. In human hypogalactia, only the lactogenic hormone has been employed, although it seems fairly certain from the animal experiments reported that whole pituitary extracts are more effective than lactogenic hormone alone. This can be attributed to the augmenting effect which these other pituitary hormones are capable of exerting on lactation. It has been the expressed belief of this laboratory that the lactogenic hormone, which has been shown to be identical with the pigeon crop gland stimulating factor (1, 2) is the hormone concerned specifically with the initiation of lactation. In a recent experiment (3) it was demonstrated that although less lactogen is required to initiate lactation in pseudopregnant rabbits when other...
Experimental Study of Fluid Jet Mixing at Supercritical Conditions

Subcritical and supercritical fluids were injected in an inert gaseous atmosphere. Density distribution was measured and density-gradient profiles were inferred from the experimental data. A novel method was applied for the detection of detailed structures throughout the entire jet center plane. The core lengths were measured for each of the cases and correlated with previous visualization results. An eigenvalue approach was taken to determine the location of maximum gradients. The results show a significant influence of chamber-to-injectant density ratio on the core length in the supercritical domain, unlike the subcritical conditions.
Ganglioside biosynthesis. Characterization of CMP-N-acetylneuraminic acid : lactosylceramide sialyltransferase in Golgi apparatus from rat liver.

An enzyme that transfers sialic acid from GMP-sialic acid to lactosylceramide was concentrated 40-50 times in Golgi apparatus from rat liver relative to total homogenates. This enzyme required detergents as dispersing agents. Of the numerous detergents tested, the combination Tween 80-Triton CF-54 (1 : 2, w/w) was the most effective in stimulating the reaction. Two apparent pH optima, at 6.35 and 5.5, were observed. The enzyme showed no requirement for a divalent cation. The Km values calculated for CMP-N-acetylneuraminic acid and lactosylceramide were 2.7 - 10(-3) and 1.3 - 10(-4) M, respectively. The enzyme could not be dissociated from Golgi apparatus fractions by treatment with ultrasound, indicating that it is tightly associated with the membrane. The newly synthesized GM3, the product of the reaction, was incorporated into or became tightly associated with the membranes of the Golgi apparatus.
Dignity, arête, and hubris in the transhumanist debate.

Setting aside the convention of writing a paper around a single theme or single line of argument, Fabrice Jotterand (2010) has written an ambitious manifesto on dignity in the enhancement debates t...
Restoration of Bayer-sampled Image Sequences

Spatial resolution of digital images are limited due to optical/sensor blurring and sensor site density. In single-chip digital cameras, the resolution is further degraded because such devices use a color filter array to capture only one spectral component at a pixel location. The process of estimating the missing two color values at each pixel location is known as demosaicking. Demosaicking methods usually exploit the correlation among color channels. When there are multiple images, it is possible not only to have better estimates of the missing color values but also to improve the spatial resolution further (using super-resolution reconstruction). In this paper, we propose a multi-frame spatial resolution enhancement algorithm based on the projections onto convex sets technique.
Grain Boundary Curvature in a Model Ni-Based Superalloy

The local grain boundary (GB) curvature in a model Ni-based superalloy was measured experimentally using Dehoff’s tangent count method. The results show that, in materials containing significant amounts of second-phase particles, the curvature parameter, κ, which relates the mean local curvature to the grain size, can adopt far lower values than have been reported previously. It is also shown that the value of κ is not a constant, as is usually assumed, but instead varies both with the volume fraction of second-phase particles and with the holding time during high-temperature annealing. The lowest values for κ were obtained for high particle volume fractions and long annealing times. Because the local boundary curvature constitutes the driving force for grain growth, these observations could help to explain grain growth phenomena in heavily pinned systems.
A Note on Enumerating Binary Trees

Abstract : Algorithms have been presented for computing a bijection between the set of binary trees on n nodes and an initial segment of the positive integers. A more complicated algorithm was also presented that computes a different bijection, claiming that their algorithm is more efficient and has advantages if a sequence of several consecutive trees is required. A modification of the first algorithm is presented that is simpler than the first and as efficient as the second. Also given is a new linear-time algorithm for transforming a tree into its successor in the natural ordering of binary trees.
Non-linear Optical Studies of Conjugated Polymer Films and Interfaces

The electronic structure of the conjugated polymer/metal interfaces that are present in polymer-based optoelectronic devices are poorly understood. In this talk, we present preliminary results of non-linear optical measurements aimed at characterizing conjugated polymer/metal interfaces.
Homologous DNA Pairing Promoted by a 20-Amino Acid Peptide Derived from RecA

The molecular structure of the Escherichia coli RecA protein in the absence of DNA revealed two disordered or mobile loops that were proposed to be DNA binding sites. A short peptide spanning one of these loops was shown to carry out the key reaction mediated by the whole RecA protein: pairing (targeting) of a single-stranded DNA to its homologous site on a duplex DNA. In the course of the reaction the peptide bound to both substrate DNAs, unstacked the single-stranded DNA, and assumed a β structure. These events probably recapitulate the underlying molecular pathway or mechanism used by homologous recombination proteins.
Evidence for Anomalous Hydration Dynamics near a Model Hydrophobic Peptide

We present new quasi-elastic neutron scattering experiments and simulation analysis for studying the hydration water dynamics of N-acetyl-leucine-methylamide (NALMA) solutions as a function of concentration and temperature. The experiments show non-Arrhenius translational dynamics over the temperature range of -3 to +37 °C for all concentrations, and fits to the experimental intermediate scattering function show nonexponential relaxation dynamics. While the lower-concentration NALMA solution could be classified as an intermediate to strong liquid, the higher concentration is legitimately defined as a fragile liquid, and the hydration dynamics of the most concentrated solution exhibits very good correspondence with the same signatures of non-Arrhenius behavior and nonexponential dynamics as that observed for supercooled water well below -20 °C. The corresponding molecular dynamics simulation analysis of the high concentration data using the SPC water model, a common companion water model used in protein simulations, is severely limited in application to the dynamics of this system because of the very low temperature of maximum density of the SPC water model. However, the simulations are informative in the sense that nonexponential relaxation is still evident at the effectively higher temperatures, which indicates that the underlying potential energy surface is very rough at high concentrations, although the sampling is still sufficiently ergodic so that Arrhenius behavior is observed. We provide discussion in regards to the mutually beneficial connection between supercooled liquids and glasses and its biological importance for protein -water systems.
Sarcoidosis Presenting as Chronic Sinusitis with Facial Fistulization

Sarcoidosis is a multisystem granulomatous disorder of unknown etiology most commonly affecting young adults and frequently presenting with bilateral hilar lymphadenopathy, pulmonary infiltration, and skin or eye lesions. Usually there is involvement of more than one organ system with clinical and radiographic findings supported by histological evidence of widespread noncaseating, epitheloid cell granulomas. The clinical course varies from a self-limited mild problem to a fulminant progressive widespread granulomatous inflammatory process producing severe fibrosis. An unusual case of sarcoidosis that presented with chronic sinusitis with fistulization onto the nasal dorsum and stenosis of the nasal vestibules is reported. The literature concerning the subject is reviewed. Long-term treatment for many years may be required to prevent clinical relapse.
The role of E-proteins in B- and T-lymphocyte development.

Abstract Development of lymphocytes from hematopoietic stem cells is controlled, in part, by the activity of transcriptional regulatory proteins. In particular, one class of helix-loop-helix proteins, termed E-proteins, have been implicated in the regulation of gene expression during B-cell development. Recent analysis of gene-targeted mice has allowed a direct assessment of the functional roles of several E-protein family members in hematopoiesis. In this review we describe the defects in B- and T-lymphocyte development in mice carrying targeted mutations in the E-protein genes and discuss our current understanding of the role of these proteins in lymphoid development.
IgM enzyme-linked immunosorbent assay test for the diagnosis of congenital Toxoplasma infection †

An IgM enzyme-linked immunosorbent assay, developed for detection of IgM antibodies to Toxoplasma gondii , was evaluated to define its usefulness for diagnosis of congenital Toxoplasma infection. Sera from 51 infants suspected of having congenital Toxoplasma infection but in whom this diagnosis was ruled out were negative in the IgM-ELISA test. Fifty of them were also negative in the IgM-fluorescent antibody test; the one which was positive was from an infant with congenital syphilis who had circulating rheumatoid factor. Of 55 sera from newborn infants with proved congenital Toxoplasma infection, the IgM-ELISA test was positive in 43 (72.7%), whereas the IgM-IFA test was positive in only 14 (25.4%). Of those sera obtained during the first 30 days of life from the infected infants, 81.2% were positive in the IgM-ELISA test, whereas only 25% were positive in the IgM-IFA test. The IgM-ELISA test avoids the false-positive results owing to RF and the false-negative results owing to competition from high levels of maternal IgG antibody which occur in the IgM-IFA test. We conclude that the IgM-ELISA test is highly sensitive and specific for diagnosis of congenital Toxoplasma infection.
Tailored Surfaces Using Optically Manipulated Colloidal Particles

Optical trapping techniques have been used extensively to manipulate biological objects and micrometer-sized colloids in a wide variety of investigations. We have used an extension of this technique, scanning laser optical trapping, to simultaneously trap multiple colloids in a designed pattern and have locked-in this artificially created structure through photopolymerization of the monomer-containing solvent. This technique can be used as a means of constructing templates for lithography or as a starting point for creation of larger three-dimensional colloidal structures.
Observation of OH (υ = 0, 1) in the reactions of O(3P) with HCl (υ = 0, 1, 2)

Abstract The analysis of the observed OH (υ = 0, 1) concentration in the laser enhanced reactions of HCl (υ = 1, 2) with O(3P) atoms demonstrates that vibrational energy in excess of the thermal activation energy barrier continues to enhance the reaction rate. This reaction also exhibits a preferential conversion of reactant vibrational excitation into product vibrational excitation.
Postmortem isolation of synaptosomes from human brain

Abstract Using a combination of differential and density gradient centrifugations, a relatively pure synaptosome fraction was isolated from both septal region and prefrontal cortex of human brains obtained 6–8 h after death. Although postmortem changes were observed in the morphology of the synaptosomes, they were still readily identifiable as synaptosomes and contained high concentrations of acetylcholinesterase and ATPase. Whereas enzymatic activity and morphology of the synaptosomes isolated from the septal region and cortex were essentially the same, acetylcholinesterase activity of those derived from the septal region was about 10 times greater. Of the 3 other distinct fractions obtained from the density gradients and subsequently characterized by electron microscopy and enzyme analysis, one, the membrane fraction, contained numerous profiles of postsynaptic origin.
The influence of methane oxidation on the stable isotopic composition of methane emitted from Florida swamp forests

This study reports the first measurements of the [delta][sup 13]C of CH[sub 4] emitted from seasonally flooded swamp forests in the southeastern United States. The seasonally averaged [delta][sup 13]C of CH[sub 4] emitted from a north Florida swamp forest located in the St. Marks National Wildlife Refuge was -52.7 [+-] 6.11[per thousand] (error is [+-] one standard deviation throughout, n = 28), a value [sup 13]C-enriched, relative to typical wetland emissions. In an Everglades cypress dome, the average [delta][sup 13]C of emitted CH[sub 4] was -52.5 [+-] 6.7 [per thousand] (n = 3). Consistent with attenuation of CH[sub 4] emission by CH[sub 4] oxidation in these environments, CH[sub 4] emitted via diffusion from the St. Marks swamp forest was enriched in [sup 13]C by 6.4 [+-] 5.8 [per thousand] (n = 28) and D by 57 [+-] 36 [per thousand] (n = 6) relative to sedimentary CH[sub 4]. Emission experiments, performed in situ with inhibitors of aerobic CH[sub 4] oxidizing bacteria, were used to calculate the fractionation factors ([alpha]) for stable carbon and hydrogen isotopes of CH[sub 4] undergoing transport and oxidation. Values ranged from 1.003 to 1.021 and 1.050 to 1.129, respectively. The best estimates for carbon and hydrogenmore » [alpha] values were 1.020 and 1.068, respectively. The [delta] values of produced (sedimentary) CH[sub 4] were relatively constant in the St. Marks subtropical swamp forest. Additionally, because the transport of CH[sub 4] to the atmosphere was dominated by molecular diffusion, variations in the magnitude of CH[sub 4] oxidation appeared to be the primary factor controlling the [delta] values of emitted CH[sub 4]. This contrasts with systems dominated by bubble ebullition, where variations in CH[sub 4] production mechanisms have been hypothesized to be the primary factor controlling the [delta] values of emitted CH[sub 4].« less
Lymph Node Staging in Colorectal Cancer: Revisiting the Benchmark of at Least 12 Lymph Nodes in R0 Resection

i m Since the development of Dukes’ classification system for colorectal carcinoma in the 1930s by English pathologist Cuthbert Dukes, which emphasized the imporance of lymph node involvement, the status of lymph odes in a colorectal cancer resection specimen has reained the most powerful indicator for prognostication nd management. The most important components in lymph node staging include the presence or absence of metastasis in lymph nodes and the total number of lymph nodes examined. The assessment of both components, however, can be influenced by many factors, and how best to carry out the assessment has been an evolving topic. This review aims at analyzing the various factors that can potentially influence lymph node assessment, and how such influences can impact the clinical application of the current benchmark requirement of at least 12 lymph nodes for a colonic or rectal cancer resection.
The Effect of Surface‐active Agents on the Permeability, Survival, and Pseudopod Formation of Pelomyxa carolinensis

SUMMARY. The effect of surface-active agents on the permeability, survival, and pseudopod formation of the rhizopod, Pelomyxa carolinensis, was studied. Surfactants increased the rate of uptake of Na22 in almost all instances. Tweens which lower surface tension, stimulated or caused pseudopod formation; Tween 80 was the least toxic. The fatty acid component as well as the hydrophile-lipophile balance of the surfactant may influence the rate.
The status of stability theory for deterministic systems

This paper attempts to summarize and place in perspective some of the recent contributions to stability theory. The major emphasis is on work which relates closely to applications in control, circuit theory, and aerospace systems. The frequency domain stability criteria for nonlinear and time-varying feedback loops are discussed in some detail. A large number of references describing both theoretical developments and applications are included.
A Methodology for the Study of the Effects of Communication Method on Design Review Effectiveness

It is necessary for product teams with diverse expertise to communicate during the product development process, notably during design reviews. As this expertise may be distributed across different geographic locations of an organization, design review teams are facing new challenges in effective communication. This paper presents the results of a controlled user study devised to examine the effectiveness of various communication methods for design reviews. Speech only, text only, and free communication methods were chosen to simulate current technologies commonly used in situations of geographic distribution. Primary results from the study include: group design reviews were approximately twice as effective as individual design reviews; free communication produced greater perceived effectiveness than speech only communication, speech only communication produced greater perceived effectiveness than text only communication; and certain personality factors, such as extroversion and intuition, may have contributed to higher productivity in design review teams.Copyright © 2003 by ASME
Single luminal epithelial progenitors can generate prostate organoids in culture

The intrinsic ability to exhibit self-organizing morphogenetic properties in ex vivo culture may represent a general property of tissue stem cells. Here we show that single luminal stem/progenitor cells can generate prostate organoids in a three-dimensional culture system in the absence of stroma. Organoids generated from CARNs (castration-resistant Nkx3.1-expressing cells) or normal prostate epithelia exhibit tissue architecture containing luminal and basal cells, undergo long-term expansion in culture and exhibit functional androgen receptor signalling. Lineage-tracing demonstrates that luminal cells are favoured for organoid formation and generate basal cells in culture. Furthermore, tumour organoids can initiate from CARNs after oncogenic transformation and from mouse models of prostate cancer, and can facilitate analyses of drug response. Finally, we provide evidence supporting the feasibility of organoid studies of human prostate tissue. Our studies underscore the progenitor properties of luminal cells, and identify in vitro approaches for studying prostate biology.
Long-term variation of fiddler crab populations in North Carolina salt marshes

Total biomass of the fiddler crabsUca pugnax andU. minax in fourSpartina marshes in the lower Cape Fear River estuary, North Carolina, declined by 65 to 70% between the summers of 1974–1975 and 1976–1977 with no significant decrease in population density; there was evidence of a recovery in summer of 1978 to the 1974–1975 levels. The cause of these fluctuations is unknown, but such a degree of variability in intertidal populations emphasizes the need for caution in using one- or two-year baseline studies to evaluate potential environmental impacts.
Pathohistological study with four kinds of stress stimulations on active endolymphatic hydrops in the guinea pig.

Meniere’s disease is believed to show pathological features of endolymphatic hydrops [1, 2], but the etiology of this disease has not yet been ascertained. Many investigators [3], have attempted to create animal models with endolymphatic hydrops by obliterating the endolymphatic sac and duct. However, this method has been unable to adequately explain the development of Meniere’s disease because it uses simulated apparatus. On the other hand, Meniere’s disease is thought to develop as a result of stress to the inner ear mechanism although there have been no reports on endolymphatic hydrops induced by stress. We conducted a short-term experiment, creating active endolymphatic hydrops by stress load, to study the occurrence rate of endolymphatic hydrops. This was followed by a light-microscopic study on the changes in permeability of the cochlear lateral wall with horseradish peroxidase and a study of the dynamics of endolymphatic hydrops.
Adaptation of cerebral oxygen metabolism and blood flow and modulation of neurovascular coupling with prolonged stimulation in human visual cortex

Prolonged visual stimulation results in neurophysiologic and hemodynamic adaptation. However, the hemodynamic adaptation appears to be small compared to neural adaptation. It is not clear how the cerebral metabolic rate of oxygen (CMRO2) is affected by adaptation. We measured cerebral blood flow (CBF) and CMRO2 change in responses to peripheral stimulation either continuously, or intermittently (on/off cycles). A linear system's response to the continuous input should be equal to the sum of the original response to the intermittent input and a version of that response shifted by half a cycle. The CMRO2 response showed a large non-linearity consistent with adaptation, the CBF response adapted to a lesser degree, and the blood oxygenation level dependent (BOLD) response was nearly linear. The metabolic response was coupled with a larger flow in the continuous condition than in the intermittent condition. Our results suggest that contrast adaptation improves energy economy of visual processing. However BOLD modulations may not accurately represent the underlying metabolic nonlinearity due to modulation of the coupling of blood flow and oxygen metabolism changes.
Erratum to The Adoption Time Period for Some Transportation Innovations

Erratum to the author's paper "The Adoption Time Period for Some Transportation Innovations," Management Sci., Vol. 25, No. 5 1979, pp. 429-443.
The Conjoint Family Drawing

A new technique, the Conjoint Family Drawing, is described as a means of assessing family functioning. The method is projective as well as interactive, reflecting individual feelings and group interaction. Fourteen randomly chosen families, whose children had been referred to a Child Psychiatry Clinic, were studied. They were observed in a structured, performance-task-oriented session where they collaborated on drawing a picture of their family, which was discussed with them on its completion. Analyzing the data on all of the family portraits, six relevant dimensions were identified: 1) organizing role, 2) sequence, 3) size, 4) choice of person, 5) isolation, and 6) content. Clinical material is presented to demonstrate the value of the Conjoint Family Drawing as a potential research instrument, a diagnostic tool and a therapeutic device.
Leveraging USB to Establish Host Identity Using Commodity Devices

Determining a computer’s identity is a challenge of critical importance to users wishing to ensure that they are interacting with the correct system; it is also extremely valuable to forensics investigators. However, even hosts that contain trusted computing hardware to establish identity can be defeated by relay and impersonation attacks. In this paper, we consider how to leverage the virtually ubiquitous USB interface to uniquely identify computers based on the characteristics of their hardware, firmware, and software stacks. We collect USB data on a corpus of over 250 machines with a variety of hardware and software configurations, and through machine learning classification techniques we demonstrate that, given a period of observation on the order of tenths of a second, we can differentiate hosts based on a variety of attributes such as operating system, manufacturer, and model with upwards of 90% accuracy. Over longer periods of observation on the order of minutes, we demonstrate the ability to distinguish between hosts that are seemingly identical; using Random Forest classification and statistical analysis, we generate fingerprints that can be used to uniquely and consistently identify 70% of a field of 30 machines that share identical OS and hardware specifications. Additionally, we show that we can detect the presence of a hypervisor on a computer with 100% accuracy and that our results are resistant to concept drift, a spoofing attack in which malicious hosts provide fraudulent USB messages, and relaying of commands from other machines. Our techniques are thus generally employable in an easy-to-use and low-cost fashion.
Effects of intratidal and tidal range variability on circulation and salinity structure in the Cape Fear River Estuary, North Carolina

[1] Tidal influences on circulation and the salinity structure are investigated in the largely unstudied Cape Fear River Estuary (CFRE), North Carolina, a partially mixed estuary along the southeast coast of the United States. During two different tidal conditions (high versus low tidal range) and when river flow was low, salinity and velocity data were collected over a semidiurnal tidal cycle in a 2.8 km long transect along the estuary axis. Water level data were recorded nearby. Mechanisms that influence salt transport characteristics are diagnosed from an analysis of the field data. Specifically, we investigated the relationship between tidal range and salinity through comparison of along-channel circulation characteristics, computed salt fluxes, and coefficients of vertical eddy diffusivity (Kz) based on a parameterization and on salt budget analysis. Findings indicate up-estuary tidally driven salt fluxes resulting from oscillatory salt transport are dominant near the pycnocline, while mean advective transport dominates near the bottom during both tidal range periods. Earlier research related to salt transport in estuaries with significant gravitational circulation suggests that up-estuary salt transport increases during low tidal ranges as a result of increased gravitational circulation. In the CFRE, in contrast, net (tidally averaged) near-bottom along-channel velocities are greater during higher tidal range conditions than during lower tidal range conditions. Findings indicate stronger tidal forcing and associated mixing contribute to greater near-bottom salinity gradients and, consequently, increased baroclinic circulation. Lower near-bottom salinities during the higher tidal range period are a result of a combination of increased vertical turbulent salt fluxes near the pycnocline and increased bottom-generated mixing. Citation: Becker, M. L., R. A. Luettich Jr., and H. Seim (2009), Effects of intratidal and tidal range variability on circulation and salinity structure in the Cape Fear River Estuary, North Carolina, J. Geophys. Res., 114, C04006, doi:10.1029/2008JC004972.
2,6‐Bis[(4S,5R)‐4,5‐dihydro‐4,5‐diphenyl‐2‐oxazolyl]pyridine

[372200-56-1] C35H27N3O2 (MW 521.61) InChI = 1S/C35H27N3O2/c1-5-14-24(15-6-1)30-32(26-18-9-3-10-19-26)39-34(37-30)28-22-13-23-29(36-28)35-38-31(25-16-7-2-8-17-25)33(40-35)27-20-11-4-12-21-27/h1-23,30-33H/t30-,31-,32-,33-/m1/s1 InChIKey = SMYDLHVQRYQCDL-XEXPGFJZSA-N (reagent used as a chiral tridentate ligand for various metal-catalyzed asymmetric transformations) Physical Data: white crystalline solid, mp 201–202 °C, [α]D25–41.4° (c 0.5 CHCl3).1 Solubility: soluble in most organic solvents. Analysis of Reagent Purity: 1H NMR (400 MHz, CDCl3): δ 8.41 (d, J = 7.8 Hz, 2H), 7.98 (t, J = 7.8 Hz, 1H), 7.30–7.40 (m, 20H), 5.54 (d, J = 8.3 Hz, 2H), 5.33 (d, J = 8.3 Hz, 2H); 13C NMR (100 MHz, CDCl3): δ 163.0, 147.1, 141.3, 139.8, 137.4, 128.81, 128.79, 128.5, 127.9, 126.9, 126.6, 126.2, 90.0, 79.0.2 Preparative Methods: the reagent (−)-1 is prepared3 by a three-step sequence starting by treating 1.0 equiv of pyridine-2,6-dicarbonyl dichloride4 with 2.0 equiv of the commercially available (1S,2R)-2-amino-1,2-diphenylethanol (Aldrich) and 5.1 equiv of triethylamine in anhydrous dichloromethane.1 The resulting white solid (2,6-bis[(1R,2S)N,N′-2-hydroxyl-1,2-diphenylethyl]pyridinedicarboxamide) is isolated by filtration and subsequently treated with thionyl chloride (16 equiv) in dichloromethane to provide the intermediate bis-chloride (2,6-bis[(1R,2S)N,N′-2-chloro-1,2-diphenylethyl]-pyridinedicarboxamide), which is cyclized by treatment with an ethanolic solution of 2 N sodium hydroxide to yield the PyBox ligand 1.1 The ligand can be purified by recrystallization from hot ethyl acetate.1 The enantiomer of the title compound (2,6-bis[(4S,5S)-4,5-dihydro-4,5-diphenyl-2-oxazoly]pyridine, (+)-1, 410092-98-7) can be prepared in an analogous manner. Handling, Storage, and Precautions: bench stable, but generally stored in a dry box. The toxicity of the reagent is unknown and should be handled in a well-ventilated fume hood.
Conflict and its resolution in the operating room

The operating room is a high-stress and volatile workplace where interpersonal conflict can be frequent and at times intense. This article explores some of the common sources of conflict and suggests some remedies.
Some new concepts concerning the role of sugar in dental caries.

Abstract The etiology of dental caries was reviewed and some new concepts of the dental plaque, based upon laboratory experiments, were proposed. A new practical method of caries control was suggested.
Uncooled laser sources for plug and play transceivers for datacom and telecom applications

Optical communication systems operating at 10Gbit/s require transceivers of low cost, size and power consumption, driving a "hot" source solution. This paper describes the current status of these "hot" devices for different applications. 10 Gb uncooled FP (Fabry Perot) to be used in conjunction with an EDC (Electronic Dispersion Compensation) receiver for LRM transceivers and CWDM (Course Wavelength Division Multiplexing) 3.125 Gb DFB for LX4 transceivers are the devices chosen for enterprise network (link up to 300m), which can address the need to transmit data at 10 Gb on the legacy multimode fibers. 10 Gb uncooled 1300 nm DFB (Distributed FeedBack) and 10 Gb 1300nm uncooled EML (Electro-absorption Modulator Laser) for LR transceivers are the devices chosen for LAN (Local Area Network) applications (link up to 10 km). Finally 10 Gb 1550 nm EML are the devices chosen for Metro applications (links up to 40 Km and potentially 80 km), for single wavelength and DWDM (Dense Wavelength Division Multiplexing) applications, so for those applications in which a directly modulated laser can not be used, due to the chromatic dispersion. All these laser sources can be used for different transceiver form factors: XENPAK, X2 and XFP.
NITROGEN TRANSFORMATIONS AND NO3− REMOVAL AT A SOIL–STREAM INTERFACE: A STABLE ISOTOPE APPROACH

The natural removal of NO3− by denitrification within riparian zones of streams and rivers is an area of considerable interest owing to its potential to minimize the impacts of excess anthropogenic loadings. In this study we utilize natural variations in stable N isotopic compositions of NO3− and NH4+ within a transect of shallow wells extending 4 m inland from Smith Creek, a southwestern Michigan stream, to provide insight into microbial processes and the extent of NO3− removal within a soil–stream interface. Within this region three water masses with unique biogeochemical characteristics intersect: a shallow flow rich in NH4+ and dissolved organic carbon (DOC), a deep groundwater mass rich in NO3− but depleted in DOC, and stream water low in NO3−, NH4+, and DOC. N isotope values for NO3− within the well transect were highly variable (−7.7–34.1‰) and reflected intense microbial activity within this narrow region. Isotopic variation was primarily controlled by upwelling of deep groundwater near the stream...
Biomedical Discovery Acceleration, with Applications to Craniofacial Development

The profusion of high-throughput instruments and the explosion of new results in the scientific literature, particularly in molecular biomedicine, is both a blessing and a curse to the bench researcher. Even knowledgeable and experienced scientists can benefit from computational tools that help navigate this vast and rapidly evolving terrain. In this paper, we describe a novel computational approach to this challenge, a knowledge-based system that combines reading, reasoning, and reporting methods to facilitate analysis of experimental data. Reading methods extract information from external resources, either by parsing structured data or using biomedical language processing to extract information from unstructured data, and track knowledge provenance. Reasoning methods enrich the knowledge that results from reading by, for example, noting two genes that are annotated to the same ontology term or database entry. Reasoning is also used to combine all sources into a knowledge network that represents the integration of all sorts of relationships between a pair of genes, and to calculate a combined reliability score. Reporting methods combine the knowledge network with a congruent network constructed from experimental data and visualize the combined network in a tool that facilitates the knowledge-based analysis of that data. An implementation of this approach, called the Hanalyzer, is demonstrated on a large-scale gene expression array dataset relevant to craniofacial development. The use of the tool was critical in the creation of hypotheses regarding the roles of four genes never previously characterized as involved in craniofacial development; each of these hypotheses was validated by further experimental work.
Mathematics assessment scenarios for at-risk students

In this paper, we describe the work by a team of university and public school mathematics educators to design mathematics assessment tasks that are effective for students who have been identified at risk in mathematics, through their failure on a state mathematics assessment. We have developed assessment tasks that have the very best chance to elicit the most mathematical knowledge possible, but are closely tied to the school curriculum and practical enough to be administered by classroom teachers. We offer some perspectives on the need for alternative mathematics assessment for at-risk students, along with the dangers inherent in this undertaking. Some practical design considerations are discussed and examples of student responses to a mathematics assessment scenario are given. Finally, policy issues related to authentic assessment are discussed.
Hepatitis C virus genotype distribution varies by underlying disease status among patients in the same geographic region: a retrospective multicenter study.

a b s t r a c t Background: Hepatitis C virus (HCV) is a known carcinogen with considerable genetic heterogeneity: six different genotypes have been identified. HCV genotype distribution varies from country to country. In the United States, the most prevalent genotypes are 1a, and 1b followed by genotypes 2, and 3. Objectives: To examine whether the distribution of HCV genotypes differed by cancer status among patients in the same area. Study design: We reviewed epidemiologic and virological data of 636 patients with HCV infection evalu- ated at 3 institutions in Houston, Texas, in 2008 and 2009. Results: We included 129 cancer patients (53 with hematologic malignancies and 76 with solid tumors), 333 immunocompetent patients, and 102 HIV-co-infected patients. The prevalence of genotype 1 (G-1) was 66% among cancer patients, 84% among immunocompetents (P = 0.00004), and 99% among HIV-co- infected patients (P < 0.00001). G-2 and G-3 were more common in cancer patients than other patients. Demographics, risk factors, and duration of HCV infection were similar between cancer and immunocom- petent patients. G-1 was more prevalent in immunocompetents (84%) than in patients with hepatocellular carcinoma (74%, P = 0.08) or lymphoma (59%, P = 0.001). G-2 was more prevalent in lymphoma patients (24%) than in immunocompetents (8%, P = 0.003); cancer risk was 3 times as great with G-2 as with other genotypes (OR 3.72, 95% CI 1.38-9.76). Conclusions: This multicenter retrospective study provides evidence of differences in HCV genotype dis- tribution by underlying disease among geographically related patients and suggests a possible greater carcinogenic potential of some variants. Large-scale prospective studies are warranted to investigate HCV genotype distribution in other regions.