cssi/SciSciGPT-SciSciNet huggingface dataset:
Neoplasm Studies I. Cells of Melanoma in Tissue Culture

Introduction A mouse melanoma discovered and described by Harding and Passey (1) was brought to our attention by workers with this tumor at the Memorial Hospital of New York.2 Attempts to grow it in tissue culture were at first unsuccessful. Harding and Passey state that such attempts, made at their instigation, “had failed to give results which would satisfy them that growth of tumour cells had actually been obtained.” In experiments made in this laboratory it was found that fragments taken from heavily pigmented tissues of the Harding and Passey melanoma markedly increase the alkalinity of the culture medium, in which case tissue growth is inhibited. By a method to be described here, it has been found possible to obviate this condition and to obtain good growth. This paper presents a description of the various types of cells which appear in the outgrowth. Melanoma appears to be closely associated with the epidermis and involves the subcutaneous tissues. The characteristic cell seems to be a highly dendritic cell, called the melanoblast or pigment-producing cell. Becker (2) has given an extended review of the literature on the origin of the pigment-producing cells in the skin and buccal mucosa. The epithelial origin claimed by Bloch (3) for the dendritic melanoblasts has been questioned by others, who consider that it arises from dermal cells or from some part of the peripheral nervous system (Masson, 4). All agree, however, that the typical cell of the melanoma is a dendritic, melanin-producing cell whether it originates from normal melanoblasts or from other cells. Associated with this melanin-producing cell in the tumor may be other cells heavily laden with pigment granules which are generally considered to be phagocytic. In sections of melanomas, the cell bodies of the neoplastic melanoblasts have been classified as fusiform or cuboid and the tumors accordingly termed sarcomatous or carcinomatous. Not much reliance can be placed on mere shape (cf. Becker, 2). The term chromatophore is descriptive, meaning a pigment-carrying cell. It does not necessarily imply that the cell possesses the property of synthesizing pigment. For this reason the term is not used in this paper.
Disordered CuN(6) Jahn-Teller Centers in Hexakis(1-methyltetrazole)copper(II) Tetrafluoroborate: A Temperature-Dependent X-ray Diffraction and EPR Study.

The influence of the molecular crystalline arrangement upon the state of a Jahn−Teller-active center has been investigated in crystals of the complex Cu(mtz)6(BF4)2, where mtz = 1-methyltetrazole. ...
Diabetic gangrene—A clinical problem

Abstract The clinical problems presented by the 559 diabetic patients operated upon for gangrene have been reviewed. The indications for major and minor amputation are discussed. The mortality following major amputations in 495 patients has been 13.9 per cent. The mortality following primary supracondylar amputations in 300 cases has been 11.7 per cent.
Control of Candida albicans Metabolism and Biofilm Formation by Pseudomonas aeruginosa Phenazines

Candida albicans has developmental programs that govern transitions between yeast and filamentous morphologies and between unattached and biofilm lifestyles. Here, we report that filamentation, intercellular adherence, and biofilm development were inhibited during interactions between Candida albicans and Pseudomonas aeruginosa through the action of P. aeruginosa-produced phenazines. While phenazines are toxic to C. albicans at millimolar concentrations, we found that lower concentrations of any of three different phenazines (pyocyanin, phenazine methosulfate, and phenazine-1-carboxylate) allowed growth but affected the development of C. albicans wrinkled colony biofilms and inhibited the fungal yeast-to-filament transition. Phenazines impaired C. albicans growth on nonfermentable carbon sources and led to increased production of fermentation products (ethanol, glycerol, and acetate) in glucose-containing medium, leading us to propose that phenazines specifically inhibited respiration. Methylene blue, another inhibitor of respiration, also prevented the formation of structured colony biofilms. The inhibition of filamentation and colony wrinkling was not solely due to lowered extracellular pH induced by fermentation. Compared to smooth, unstructured colonies, wrinkled colony biofilms had higher oxygen concentrations within the colony, and wrinkled regions of these colonies had higher levels of respiration. Together, our data suggest that the structure of the fungal biofilm promotes access to oxygen and enhances respiratory metabolism and that the perturbation of respiration by bacterial molecules such as phenazines or compounds with similar activities disrupts these pathways. These findings may suggest new ways to limit fungal biofilms in the context of disease. IMPORTANCE Many of the infections caused by Candida albicans, a major human opportunistic fungal pathogen, involve both morphological transitions and the formation of surface-associated biofilms. Through the study of C. albicans interactions with the bacterium Pseudomonas aeruginosa, which often coinfects with C. albicans, we have found that P. aeruginosa-produced phenazines modulate C. albicans metabolism and, through these metabolic effects, impact cellular morphology, cell-cell interactions, and biofilm formation. We suggest that the structure of C. albicans biofilms promotes access to oxygen and enhances respiratory metabolism and that the perturbation of respiration by phenazines inhibits biofilm development. Our findings not only provide insight into interactions between these species but also provide valuable insights into novel pathways that could lead to the development of new therapies to treat C. albicans infections.
Dynamic priority scheduling of periodic and aperiodic tasks in hard real-time systems

This paper addresses the problem of scheduling aperiodic tasks in real-time systems. The proposed scheme combines the Earliest-Deadline-First algorithm for scheduling periodic tasks with the Deferrable Server approach for servicing aperiodic tasks. Necessary and sufficient conditions are derived for guaranteeing feasibility of a given periodic task set when a deferrable server is present. An analytic model is proposed for selecting the best feasible period and computation time of the server to minimize the mean response time of aperiodic tasks. An evaluation of the proposed model using a simulator indicates that the server parameters selected by the model result in mean response times that are close to the best mean response time determined by the simulator.
The role of gadolinium enhanced magnetic resonance imaging for children with suspected acute pyelonephritis.

ABSTRACTPurpose: The diagnosis of pyelonephritis is primarily clinical. However, the history and physical findings can be confusing in children, leading to adjunctive nuclear renal cortical scintigraphic studies (99mtechnetium dimercapto-succinic acid [DMSA]) to confirm the diagnosis. Nonetheless, ambiguity occurs when differentiating between acute pyelonephritis and chronic scarring. We report our initial experience with gadolinium enhanced inversion recovery magnetic resonance imaging (MRI) to diagnose acute pyelonephritis.Materials and Methods: Nine patients 7 months to 18 years old (mean age 81 months) underwent MRI to confirm radiographically a clinical suspicion of acute pyelonephritis. All patients had at least 1 prior episode of clinical pyelonephritis. Data were collected to determine whether acute pyelonephritic changes could be differentiated from chronic pyelonephritis on the basis of MRI characteristics.Results: Of the 9 patients 4 were identified as having acute pyelonephritis on MRI (persis...
Thermocapillary drift of a droplet in reduced gravity

Abstract The combination of buoyancy and thermocapillarity can cause a flow that impedes or alters the motion of a droplet in reduced gravity. A solution to the governing equations of motion and energy in the limit as Re →0 is presented. This solution provides the means to determine the terminal velocity, the direction of motion, the internal and external flows, and the temperature field of a droplet. Its features explicitly account for all gravity levels by using a Bond number that includes the Marangoni number and considers both the positive and negative variation of the surface tension with temperature. The results of the analysis indicate that one can identify five distinct flow regimes about the droplet as the Bond number changes from small to very large values, i.e., from thermocapillary to gravity dominated flow. Streamline patterns both inside and outside the droplet, are computed to obtain an overall picture of these five flow regimes. Examination of the streamline patterns allows for the determination of the manner in which the migration of the droplet can be affected.
Human urinary bladder epithelial cells lacking wild-type p53 function are deficient in the repair of 4-aminobiphenyl-DNA adducts in genomic DNA.

Abstract The effect of the tumor suppressor gene TP53 on repair of genomic DNA damage was examined in human urinary bladder transitional cell carcinoma (TCC) cell lines. Utilizing TCC10 containing wild-type p53 (wt-p53) as the parental line, an isogenic set of cell lines was derived by retroviral infection that expressed a transdominant mutant p53 (Arg → His at codon 273, TDM273-TCC10), or the human papilloma virus 16-E6 oncoprotein (E6-TCC10). 32 P-postlabeling analyses were performed on DNA from TCC cultures obtained after treatment with N -hydroxy-4-aminobiphenyl ( N -OH-ABP), N -hydroxy-4-acetylaminobiphenyl ( N -OH-AABP) and N -acetoxy-4-acetylaminobiphenyl ( N -OAc-AABP). The major adduct was identified as N -(deoxyguanosin-8-yl)-4-aminobiphenyl (dG-C8-ABP) with all three chemicals. The amount of adducts in urothelial DNA ranged between 0.1 and 20 per 10 6 nucleotides, N -OAc-AABP yielding the highest levels, followed by N -OH-ABP and N -OH-AABP. To determine, if the functional status of p53 affects the rate of repair of dG-C8-ABP in genomic DNA, TCC10 and the TDM273-TCC10 and E6-TCC10 isotypes were exposed to N -OH-AABP for 12 h and the DNA damage was allowed to repair up to 24 h. The adduct levels were quantified and compared between the TCC10 isotypes. The amounts of dG-C8-ABP that remained in genomic DNA from E6-TCC10 and TDM273-TCC10 were approximately two-fold higher, as compared to the parental TCC10. At the dose used for DNA repair studies, N -OH-AABP or N -OAc-AABP did not induce apoptosis in TCC10. However, N -OAc-AABP at high doses (>5 μM) induced apoptosis, as evidenced by DNA fragmentation analyses. Furthermore, N -OAc-AABP-mediated apoptosis was independent of the functional status of wt-p53, since both E6-TCC10 and the parental TCC10 exhibited DNA fragmentation following treatment. These results suggest that p53 might modulate the repair of DNA adducts generated from the human bladder carcinogen ABP in its target human uroepithelial cells. This implies that in p53 null cells the unrepaired DNA damage could cause accumulation of mutation, which might contribute to increased genomic instability and neoplastic progression.
Managing the last eights: three ways forward for IPv6

IP addresses are critical resources for Internet development. The available IPv4 address pool is projected to fully allocated within 3--5 years, but the deployment of the alternative protocol, IPv6, is not accelerating. Recently, several proposals have introduced new approaches to managing IPv4 allocation. However, the market proposals in particular imply fundamental changes to the nature of IPv4 address allocation. This work analyzes the allocation history of ARIN, the organization which manages address allocation in the America region. Based on the historical data and projected trends, we propose three simple management policies which can be immediately implemented with limited resources and without either significant registrar cost nor drastic modifications on current allocation strategy. We verify the effectiveness of our policies using historical data.
Modeling and numerical simulation of biotin carboxylase kinetics: Implications for half-sites reactivity

Biotin carboxylase catalyzes the ATP-dependent carboxylation of biotin and is one component of the multienzyme complex acetyl-CoA carboxylase that catalyzes the first committed step in fatty acid synthesis in all organisms. In Escherichia coli, biotin carboxylase exists as a homodimer where each subunit contains a complete active site. In a previous study (Janiyani, K., Bordelon, T., Waldrop, G.L., Cronan Jr., J.E., 2001. J. Biol. Chem. 276, 29864-29870), hybrid dimers were constructed where one subunit was wild-type and the other contained an active site mutation that reduced activity at least 100-fold. The activity of the hybrid dimers was only slightly greater than the activity of the mutant homodimers and far less than the expected 50% activity for completely independent active sites. Thus, there is communication between the two subunits of biotin carboxylase. The dominant negative effect of the mutations on the wild-type active site was interpreted as alternating catalytic cycles of the active sites in the homodimer. In order to test the hypothesis of oscillating catalytic cycles, mathematical modeling and numerical simulations of the kinetics of wild-type, hybrid dimers, and mutant homodimers of biotin carboxylase were performed. Numerical simulations of biotin carboxylase kinetics were the most similar to the experimental data when an oscillating active site model was used. In contrast, alternative models where the active sites were independent did not agree with the experimental data. Thus, the numerical simulations of the proposed kinetic model support the hypothesis that the two active sites of biotin carboxylase alternate their catalytic cycles.
Molecular orbital theory of the hydrogen bond. 27. Substituent effects in water: 4‐R‐pyrimidine complexes

Ab initioSCF calculations with the STO-3G basis set have been performed to investigate substituent effects on the structures and stabilization energies of water:4-R-pyrimidine complexes, with R including CH3, NH2, OH, F, C2H3, CHO, and CN. Except for the cyclic water:4-aminopyrimidine complex hydrogen bonded at N3, these complexes have open structures stabilized by a nearly linear hydrogen bond formed through a nitrogen lone pair of electrons. When hydrogen bonding occurs at N3, the complexes may have planar or perpendicular conformations depending on the substituent, but when hydrogen bonding occurs at N1, the perpendicular is generally slightly preferred, and there is essentially free rotation of the 4-R-pyrimidine. Primary substituent effects alter the electronic environment at the nitrogens, and tend to make N3 a poorer site for hydrogen bonding than N1, primarily because of a stronger π electron-withdrawing effect at N3. However, the relative stabilities of complexes hydrogen bonded at N1 and N3 are also influenced by secondary substituent effects, which may be significant in stabilizing complexes bonded at N3. Substitutent effects on the structures and stabilization energies of the water:4-R-pyrimidine complexes are similar to substitutent effects in water:2-R-pyridine and water:4-R-pyrimidine complexes are similar to substitutent effects in water:2-R-pyridine and water:4-R-pyridine complexes. Configuration interaction calculations indicate that although absorption of energy by the pyrimidine ring destabilizes the water:4-R-pyrimidine complexes, these may still remain bound in the excited n → π* state. This is in contrast to the fate of open water:2-R-pyridine and water:4-R-pyridine complexes, which dissociate in this state.
Threshold analysis of a chirped-grating distributed-feedback laser with the power series method

A new and efficient method for analyzing a chirped-grating distributed-feedback (DFB) laser is presented. We show that coupled-wave equations can be solved by use of the power series method. The single-mode gain margin of a linearly chirped-grating DFB laser is calculated for different chirping factors and coupling constants. We found that clearly optimum chirping exists for which the single-mode gain margin is maximum. The gain margins were also calculated for different positions of the cavity center. The effect of facet reflectivities and their phases on the gain margin was investigated. We found that the gain margin is maximum and the spatial hole burning is minimum for the cavity center at the middle of the laser cavity.
The Stability of a Partial Correlation Index for Identifying Items that Perform Differentially in Subgroups

The stability was evaluated of a partial correlation index and two other methods-comparisons of item characteristic curves and comparisons of item difficulties-in assessing race (white vs. black) and sex differences in the performance of verbal items on the GRE Aptitude Test. In general, the partial correlation index, like the other indexes, exhibited substantial consistency in identifying the same items in different samples from the same populations and displayed appreciable congruence in its values in these samples. The major exception concerned the general instability of the indexes in the analyses of sex differences for blacks, probably stemming from the small samples of blacks involved. It was tentatively recommended that all these indexes be restricted to samples of a least 1,500, with no fewer than 300 in the smallest subgroup.
Measuring polarized gluon and quark distributions with meson photoproduction

The authors calculate polarization asymmetries in photoproduction of high transverse momentum mesons, focusing on charged pions, considering the direct, fragmentation, and resolved photon processes. The results at very high meson momentum measure the polarized quark distributions and are sensitive to differences among the existing models. The results at moderate meson momentum are sensitive to the polarized gluon distribution and can provide a good way to measure it. Suitable data may come as a by-product of deep inelastic experiments to measure g{sub 1} or from dedicated experiments.
Effects of Prenatal Morphine and Cocaine Exposure on Spinal Sexual Reflexes in Male and Female Rats

Abstract Vathy, I. and L. Marson. Effects of prenatal morphine and cocaine exposure on spinal sexual reflexes in male and female rats. PHYSIOL BEHAV 63(3) 445–450, 1998.—Previous studies demonstrated that in utero exposure to morphine or cocaine differentially alters adult sexual behaviors, which are dependent on circulating gonadal hormones in male and female rats. In the present study, the effects of in utero morphine and cocaine exposure on the urethrogenital reflex were examined. The urethrogenital reflex is thought to be a hormone-independent spinal sexual reflex in both males and females. This reflex is tonically inhibited by supraspinal neurons but can be consistently evoked by urethral stimulation in the spinally transected animals. Prenatal morphine or cocaine exposure did not remove the supraspinal inhibition of the urethrogenital reflex in spinally intact male or female rats. In spinally transected animals, the urethrogenital reflex was qualitatively similar in all groups. However, morphine-exposed males required a stronger stimulus to elicit the urethrogenital reflex but once elicited, the frequency of the urethrogenital reflex was significantly higher compared to either controls or cocaine-exposed males. In contrast, in female rats, neither prenatal morphine nor cocaine exposure had any effect on the urethrogenital reflex. Thus, the urethrogenital reflex appears to be differentially affected by prenatal exposure to morphine in males and females.
Some effects of system idealizations, singularities and mesh patterns on finite element solutions

Abstract Solution accuracy, convergence, and rate of convergence are of paramount importance in finite element analysis. Important variables affecting the solution, in addition to the particular finite element utilized are structural idealizations, singularities and mesh pattern. These are the variables considered in this article. Numerical examples are considered to demonstrate some of the effects of these variables on the solution convergence. The example problems indicate monotonie upper or lower bound solution convergence for conforming elements in the proper n - sequence when idealization and discretization errors are of the same sign. For singularity cases, solution convergence is usually well behaved for practical n values, but at a reduced rate of convergence. Various mesh patterns did affect solution accuracy, but did not affect convergence or convergence rate.
Extension of Nanothermodynamics to Include a One-Dimensional Surface Excess

The problem of a long one-dimensional adsorbed lattice gas, with an adsorbent molecule at one end that creates a local mean surface excess, is recast as an example of nanothermodynamics: the surface excess itself (calculated by use of a reference system) can be viewed as a small thermodynamic system.
Connecting with consumers: marketing for new marketplace realities

Allan Kimmel’s Connecting with Consumers: Marketing for New Marketplace Realities presents a timely discourse on challenges and opportunities for twenty-first-century marketers. Kimmel, a social ps...
Exsolution in Clinoamphiboles

Ten amphibole specimens from a variety of metamorphic rocks such as talc schists, eclogites, and metamorphosed iron formations contain lamellae of a second amphibole oriented parallel to ([unknown]101) or (100), or both, of the host. Tremolites, actinolites, and hornblendes commonly have lamellae of a calcium-poor clinoamphibole with P 21 /m space-group symmetry, or lamellae of cummingtonite with C 2 /m space-group symmetry. Likewise cummingtonites and P 21 /m clinoamphiboles commonly contain lamellae of calcium-rich C 2 /m amphiboles such as tremolite. Results of x-ray diffraction, electron-probe, and microscope studies indicate that most lamellae result from unmixing of a homogeneous amphibole. The P 21 /m clinoamphibole is analogous to the clinopyroxene pigeonite in agreement with the results of M. G. Bown.
Using data augmentation via the Gibbs Sampler to incorporate missing covariate structure in linear models for ecological assessments

Missing covariate values in linear regression models can be an important problem facing environmental researchers. Existing missing value treatment methods such as Multiple Imputation (MI), the EM algorithm and Data Augmentation (DA) have the assumption that both observed and unobserved data come from the same distribution, most commonly a multivariate normal or a conditionally multivariate normal family. These methods do try to incorporate the missing data mechanism and rely on the assumption of Missing At Random (MAR). We present a DA method which does not rely on the MAR assumption and can model missing data mechanisms and covariate structure. This method utilizes the Gibbs Sampler as a tool for incorporating these structures and mechanisms. We apply this method to an ecological data set that relates fish condition to environmental variables. Notice that the presented DA method detects relationships that are not detected when other missing data methods are employed.
On the reaction of calcium with thiocyanate-liquid-ammonia solutions☆

Abstract The stoichiometry of the dissolution of Li, Na, K, Mg and Ca in liquid ammonia solutions containing NH 4 SCN or KSCN has been determined. In the temperature range between −20 and −45°C, and in the concentration range of 15–30 mol-% thiocyanate, calcium reacts with NH 4 SCN solutions according to the stoichiometric equations Ca + 2NH 4 + → Ca 2+ H 2 + 2NH 3 , Ca + SCN − → CaS + CN − . Li, Na, K and Mg react with NH 4 SCN solutions forming only H 2 . Li, Na, K and Ca react with KSCN solutions forming only sulphide and cyanide, while Mg reacts extremely slowly, and yields only hydrogen. Although the calcium appears to react with the solute at all thiocyanate concentrations, the rate of dissolution decreases with increasing thiocyanate concentration. This observation may be explained by assuming that the rate-controlling step is Ca + n NH 3 → [Ca 2+ (NH 3 ) n ]e 2 2− .
Curiosity rover LEGO® version could land soon

Now that NASA's Curiosity rover has landed on Mars, a smaller LEGO® plastic brick construction version could be landing in toy stores. Less than 2 weeks after Curiosity set down on 5 August, a LEGO® set concept model designed by a mechanical and aerospace engineer who worked on the real rover garnered its 10,000th supporter on the Web site of CUUSOO, a Japanese partner of the LEGO® group. That milestone triggered a company review that began in September 2012 to test the model's “playability, safety, and ft with the LEGO® brand,” according to a congratulatory statement from the company to designer Stephen Pakbaz. Pakbaz told Eos that he has been an avid LEGO® and space exploration fan for most of his life. “For me, creating a LEGO® model of Curiosity using my firsthand knowledge of the rover was inevitable. What I enjoyed most was being able to faithfully replicate and subsequently demonstrate the rocker-bogie suspension system to friends, family, and coworkers,” he noted, referring to the suspension system that allows the rover to climb over obstacles while keeping its wheels on the ground. Pakbaz, who is currently with Orbital Sciences Corporation, was involved with aspects of the rover while working at the Jet Propulsion Laboratory from 2007 to 2011 as a mechanical engineer.
Therapy with victimized children and their families

The treatment of children who have been sexually abused requires intervention at the individual, parental, and family level. A treatment model is proposed to address the negative affect, distorted beliefs, sexualized behavior, and disturbed personality development often associated with sexual abuse.
An extensive and improved circuit simulation methodology for NBTI recovery

A feasible computational framework that enables improved predictability of NBTI degradation within commercially available tools is discussed. The NBTI model is used for both delay correction in transistor characterization data and real-time circuit operation where recovery is present. The complementary nature of implementation is readily incorporated into existing model extraction and verification tools. The method provides significantly enhanced accuracy in simulations when compared to circuit data, yet retains practicality and flexibility.
Karyometric studies and quantitation of the DNA content in nerve and oligodendroglial cells after intraperitoneal administration of Vincristine.

Summary Karyometric and cytophotometric investigations were conducted on nuclei of nerve cells of the Gyrus cinguli and on oligodendroglial nuclei of the corpus callosum following a 12-fold intraperitoneal injection of Vincristine into Wistar rats. The results of our investigations have shown a distinctly decreased content of DNA in neuronal nuclei of experimental rats along with a slightly increased content of DNA in glial cells. It is assumed that intraperitoneal administration of Vincristine does not inhibit the replication of DNA by oligodendroglial cells and that the observed reduction of DNA in neurocytes is the result of a disturbed turnover of DNA that is due to some damage of cytoplasmatic structures (rough endoplasmatic reticulum and microtubules) induced by the applied cytostatic compound.
An argon-ion laser fluorometer optimal for concentration detection of 5-bromomethyl fluorescein derivatized carboxylic acids

A continuous wave, argon ion laser-induced fluorescence detector was designed for use with conventional high performance liquid chromatography. Palmitic acid was selected as a model analyte to evaluate the performance of the detector. Using the intense 488.0 nm emission line, a concentration detection limit of 7.5 × 10−10M (38 femtomoles on-column) was established for palmitic acid at a signal to noise ratio of three. The linear dynamic range extended over two orders of magnitude with a correlation coefficient of 0.9998. The contribution of scattered radiation to the analytical signal was minimal. The concentration detection limit achieved with the constructed laser fluorometer was superior to other reports for fatty acids.
Demonstration of grid-enabled ensemble Kalman Filter data assimilation methodology for reservoir characterization

Ensemble Kalman filter data assimilation methodology is a popular approach for hydrocarbon reservoir simulations in energy exploration. In this approach, an ensemble of geological models and production data of oil fields is used to forecast the dynamic response of oil wells. The Schlumberger ECLIPSE software is used for these simulations. Since models in the ensemble do not communicate, message-passing implementation is a good choice. Each model checks out an ECLIPSE license and therefore, parallelizability of reservoir simulations depends on the number licenses available. We have Grid-enabled the ensemble Kalman filter data assimilation methodology for the TIGRE Grid computing environment. By pooling the licenses and computing resources across the collaborating institutions using GridWay metascheduler and TIGRE environment, the computational accuracy can be increased while reducing the simulation runtime. In this paper, we provide an account of our efforts in Grid-enabling the ensemble Kalman Filter data assimilation methodology. Potential benefits of this approach, observations and lessons learned will be discussed.
Local F-actin Network Links Synapse Formation and Axon Branching

Axonal branching and synapse formation are tightly linked developmental events during the establishment of synaptic circuits. Newly formed synapses promote branch initiation and stability. However, little is known about molecular mechanisms that link these two processes. Here, we show that local assembly of an F-actin cytoskeleton at nascent presynaptic sites initiates both synapse formation and axon branching. We further find that assembly of the F-actin network requires a direct interaction between the synaptic cell adhesion molecule SYG-1 and a key regulator of actin cytoskeleton, the WVE-1/WAVE regulatory complex (WRC). SYG-1 cytoplasmic tail binds to the WRC using a consensus WRC interacting receptor sequence (WIRS). WRC mutants or mutating the SYG-1 WIRS motif leads to loss of local F-actin, synaptic material, and axonal branches. Together, these data suggest that synaptic adhesion molecules, which serve as a necessary component for both synaptogenesis and axonal branch formation, directly regulate subcellular actin cytoskeletal organization.
Finding dependencies between actions using the crowd

Activity recognition can provide computers with the context underlying user inputs, enabling more relevant responses and more fluid interaction. However, training these systems is difficult because it requires observing every possible sequence of actions that comprise a given activity. Prior work has enabled the crowd to provide labels in real-time to train automated systems on-the-fly, but numerous examples are still needed before the system can recognize an activity on its own. To reduce the need to collect this data by observing users, we introduce ARchitect, a system that uses the crowd to capture the dependency structure of the actions that make up activities. Our tests show that over seven times as many examples can be collected using our approach versus relying on direct observation alone, demonstrating that by leveraging the understanding of the crowd, it is possible to more easily train automated systems.
Regulation of rhodopsin kinase by autophosphorylation.

Abstract Rhodopsin kinase (RK) catalyzes the phosphorylation of rhodopsin (Rho) as one of the steps in quenching photoactivated Rho. In this work, we investigated the autophosphorylation of RK and how it affects the interaction between RK and Rho. RK undergoes intramolecular phosphorylation, resulting in the incorporation of three or four phosphates per RK molecule. Phosphorylated RK subsequently is a substrate for protein phosphatases 2A and 2B. We isolated three forms of RK based on their differential interactions with heparin-Sepharose. Fully phosphorylated RK (alpha-RK) binds tightly to Rho but has significantly lower affinity to phosphorylated Rho, whereas unphosphorylated RK (gamma-RK) binds avidly to both forms of Rho. The heterogenous intermediately phosphorylated RK (beta-RK) was not studied. Our data support the hypothesis that RK dissociates from Rho when both Rho and RK become phosphorylated, thereby allowing the binding of arrestin to phosphorylated Rho. These results suggest that autophosphorylation plays an important role in regulating the binding of RK to Rho and that the binding sites of RK and arrestin overlap at least partially.
The HEDIS Medication Management for People with Asthma Measure is Not Related to Improved Asthma Outcomes.

Background A new Healthcare Effectiveness Data and Information Set (HEDIS) asthma quality-of-care measure designed to quantify patient adherence to asthma controller medication has been implemented. The relationship between this measure and asthma outcomes is unknown. Objective To examine the relationship between the HEDIS Medication Management for people with Asthma (MMA) measure and asthma outcomes. Methods Administrative data identified 30,040 patients who met HEDIS criteria for persistent asthma during 2012. These patients were classified as compliant or noncompliant with the MMA measure at the 75% and 50% threshold, respectively. The association between MMA compliance in 2012 and asthma outcomes in 2013 was determined. Results Patients who were 75% or 50% MMA compliant in 2012 showed no clinically meaningful difference in asthma-related hospitalizations, emergency department visits, or rescue inhaler dispensing in 2013 compared with those who were noncompliant. Stepwise comparison of patients who were 75% or more, 50% to 74%, and less than 50% MMA compliant showed no meaningful difference in asthma outcomes between groups. Conclusions Compliance with the HEDIS MMA measure is not related to improvement in the asthma outcomes assessed (rescue inhaler dispensing, asthma-coded hospitalizations, or asthma-coded emergency department visits).
Fusion of phosphatidic acid-phosphatidylcholine mixed lipid vesicles

Ca2+-induced transformation of phosphatidylcholine-phosphatidic acid vesicles to larger bilayer structures has been examined using nuclear magnetic resonance, electron microscopy, gel permeation and radioisotope tracer techniques. For concentrated vesicle preparations where phosphatidic acid content remains less than 50% of total lipid, transformation to larger well defined unilamellar structures can be induced. The size of the product formed is dependent on phosphatidic acid content and on Ca2+ content when Ca2+ levels are between 0.3 and 1.0 mol ratios with respect to phosphatidic acid. During transformation bilayer composition remains unchanged and internal contents are retained in the final structure. These properties are indicative of concerted two vesicle and multiple vesicle fusions. The controllable and concerted fusions make the phosphatidic acid system suitable for further mechanistic studies.
Penicillin allergy: prevalence of vague history in skin test-positive patients

Objective Penicillin (PCN) skin testing is a reliable tool for predicting which patients can safely receive the antibiotic. Depending on the study, 7% to 76% of patients who have a history of PCN allergy have positive PCN skin tests. Many physicians approach patients who have a vague history of PCN allergy less cautiously than they approach those who have a convincing history suggestive of an IgE-mediated reaction. We reviewed the published literature to determine how many patients who had a history of PCN allergy and who were skin test-positive had a vague history of allergy. Data Sources By cross-referencing the keywords “penicillin” and “skin test,” an Ovid MEDLINE search for English language studies published from 1966 to 1998 was performed. Study Selection Studies in which history positive/skin test-positive patients were identified, and which contained documentation of the type of previous reaction in these patients, were included in the analysis. The MEDLINE search revealed 295 English language articles, of which 27 fulfilled the inclusion criteria. Three additional studies published prior to 1966 (and therefore not available through MEDLINE) also were found, bringing the total to 30. A “convincing” history was defined to be one likely to be IgE-mediated (such as anaphylaxis, urticaria, angioedema or pruritic rash). A “vague” history was one unlikely to be IgE-mediated (such as maculopapular rash, GI symptoms, or an unknown reaction). Results Overall, 347/1063, or 33%, of history positive/skin test-positive patients had a vague PCN allergy history, with a range of 0% to 70% among the 30 studies. Conclusion A large proportion of patients who have PCN-specific IgE antibodies, as determined by skin testing, have vague PCN allergy histories. These results therefore, indicate that, like patients with convincing histories, patients with vague allergic histories should undergo PCN skin testing prior to PCN administration.
Elastic properties of single and multilayered nanotubes

Abstract Elastic properties of single- and multilayered nanotubes are calculated using an empirical model. It is predicted that the nanotubes are the strongest materials. The Young's modulus and the shear modulus are comparable to that of the diamond, but the bulk modulus is almost twice as large. Elastic moduli are shown to be insensitive to details of nanotube structure such as helicity, tube radius and number of layers. These unusual properties ensure that nanotubes will have a wide range of potential applications.
An infrared spectroscopic study of water-related species in silica glasses

Abstract Infrared (IR) spectroscopic measurements were made on types I, III and IV silica glass specimens before and after they were subjected to heat treatments at 80–1150°C in low-pressure steam, ambient air and dry air. In addition to the standard silanol band at 3672 cm−1, IR features attributed to free, hydrogen-bonded and structurally bound molecular water and to silanol which is hydrogen-bonded to neighboring silanol groups, water molecules and chlorine impurities were found to exist even in glasses with maximum total water concentrations of less than approximately 500 ppm H2O by weight. The existence of these species and their behaviors during heat treatments suggest a specific mechanism for the reaction between silica glass and molecular water. In addition, it is shown that the glass-water reaction does not attain equilibrium instantaneously at temperatures below 750°C.
Prediction of turbulent heat transfer in rotating smooth square ducts

A two-equation turbulence model with new terms for Coriolis and rotational buoyancy has been used for prediction of heat transfer from the leading and trailing sides of a rotating square channel with radially outward flow. Test cases with different Reynolds, Grashof, and rotation numbers are considered. Modeling terms for the Coriolis and buoyancy effects in the k and e transport equations are shown to give predictions that are in better agreement with the experimental data. Flow separation at the leading wall is found to enhance heat transfer. The mechanism of flow separation is explained with a non-dimensional parameter that characterizes an adverse buoyancy force.
Motion and depth perception using spatiotemporal frequency analysis

Motion information is extracted by identifying the temporal signature associated with the textured objects in the scene. In this paper, we present a new computational framework for motion perception. Our methodology considers spatiotemporal frequency (STF) domain analysis to extract the optical flow information. First, we show that a sequence of image frames can be used to extract the motion parameters for the different regions in a dynamic scene using the basic Fourier transform properties in the STF analysis approach. When the observer (or the camera) moves, motion is induced in the scene, and the extracted motion information can then be used to estimate the depth parameters. A detailed analytical description of this model to interchangably extract motion and depth parameters and results to highlight their salient properties are presented. >
Partitioning of spherical solutes into sponge‐type materials

Partition coefficients are computed for hard spherical solutes in equilibrium with sponge-type matrices containing randomly-placed spherical cavities or pores using grand canonical Monte Carlo simulation. The random pore model is representative of a variety of disordered porous solids including porous glasses and some polymeric materials. The algorithm used brings additional realism to the problem by rigorously distinguishing between accessible and inaccessible pore space. The simulation results display significant concentration effects which are often observed experimentally and are compared to data obtained by Brannon and Anderson (1982) for the partitioning of bovine serum albumin into controlled-pore glass.
The Prevalence Of Physician Self-Referral Arrangements After Stark II: Evidence From Advanced Diagnostic Imaging

Using data from a large insurer in California, we identified the self-referral status of providers who billed for advanced imaging in 2004. Nearly 33 percent of providers who submitted bills for magnetic resonance imaging (MRI) scans, 22 percent of those who submitted bills for computed tomography (CT) scans, and 17 percent of those who submitted bills for positron-emission tomography (PET) scans were classified as “self-referral.” Among them, 61 percent of those who billed for MRI and 64 percent of those who billed for CT did not own the imaging equipment. Rather, they were involved in lease or payment-per-scan referral arrangements that might violate federal and state laws.
An atlas of aromatase mRNA expression in the zebra finch brain

Neural conversion of androgen to estrogen by aromatase is an important step in the development and expression of masculine behavior in mammals and birds. In contrast to the low telencephalic levels of aromatase in adult mammals and nonsongbirds, the zebra finch telencephalon possesses high aromatase activity. This study maps, by in situ hybridization, cells that express aromatase mRNA in the adult zebra finch telencephalon, diencephalon, midbrain, and pons. High aromatase mRNA expression was observed in the caudal neostriatum, limbic archistriatum, and hypothalamus. The hippocampus, parahippocampal area, and hyperstriatum accessorium contained cells expressing moderate amounts of aromatase message. Weakly labeled cells were found in the rostral neostriatum, lobus parolfactorius, and mesencephalic reticular formation. These findings are consistent with aromatase activity measurements of zebra finch tissue and document with anatomical precision both the widespread expression of aromatase mRNA in the brain and novel sites of brain aromatase. This study identifies the caudal neostriatum as a major site of telencephalic aromatase. A previous survey (Gahr et al., 1993: J. Comp. Neurol. 327:112-122) of several avian species found that the presence of estrogen receptors in parts of the caudal neostriatum is unique to songbirds, which are the only birds to possess the elaborated telencephalic song system. Together, these findings suggest that the heightened estrogen synthesis and estrogen sensitivity of the passerine caudal neostriatum may have some functional relation with the telencephalic circuits responsible for song.
Derivation of a pediatric growth curve for inferior vena caval diameter in healthy pediatric patients: brief report of initial curve development.

Background A validated tool has long been sought to provide clinicians with a uniform and accurate method to assess hydration status in the pediatric emergency medicine population. Outpatient clinicians use CDC height- and weight-based curves for the assessment of physical development. In hospital, daily weights provide objective data; however, these are usually not available at presentation. One of the most promising techniques for the rapid assessment of volume is ultrasound (US) to obtain an indexed inferior vena cava diameter (IVCDi); as previously described. Prior studies have focused on IVCDi in dehydrated patients and have shown that it provides accurate estimates of right atrial pressure and volume status. The objective of this study is to derive an IVC growth curve in healthy pediatric patients.
Effects of chlorine injury, starvation, and Colitag(TM) enrichment on sandwich enzyme-linked immunosorbent assay (sELISA) detection of Escherichia coli O157:H7.

Abstract The validity of ELISA for detection of E. coli O157:H7 under many conditions is not proven. In this work, sELISA was able to detect bacteria after sub‐lethal chlorine exposure and after seven days of starvation with little to no change in limit of detection and fluorescence signal as long as chlorine was not present in the sample or was neutralized by sodium thiosulfate. After Colitag™ enrichment, sELISA detected ∼3 colony forming units/ml of originally added E. coli O157:H7. Thus, the present sELISA is valid for detection of E. coli O157:H7 in water sources, although sample matrices may interfere with assay.
Role-modelling in the operating room: medical student observations of exemplary behaviour.

Medical Education 2011: 45: 946–957 CONTEXT Training future doctors to develop an appropriate professional persona is an important goal of medical student education and residency training. Most medical education research paradigms on professionalism have focused largely on lapses (e.g. yelling as an example of communication failure) and tend to emphasise behaviour that should be avoided. The assumption is that, if left unchecked, students will see these negative behaviours exhibited by their role models and possibly emulate them, allowing the potential reinforcement of the inappropriate behaviours. OBJECTIVES Identifying and characterising exemplary, or positive, behaviours can be similarly valuable to both medical students and residents as tangible examples of behaviours to strive towards. The goal of the present research was to determine and thematically define the exemplary professional actions that medical students observe in the intense and patient-focused environment of the operating room (OR). METHODS Using qualitative methodology of content analysis and theme identification, we systematically documented the type of exemplary professional behaviours reported by medical students (n = 263) when observing health care teams on an anaesthesia rotation in the OR. RESULTS The analysis generated a taxonomy of exemplary OR behaviour that included six overarching themes (e.g. teamwork), 15 sub-themes (e.g. collegial) and numerous exemplars (e.g. showed mutual respect). These themes and sub-themes were then conceptually ‘matched’– through the use of antonyms – to complement an existing framework focused on medical student reports of professional lapses witnessed during medical school. CONCLUSIONS Year 3 medical students in the USA reported observing very positive, exemplary health care provider interactions that were diverse in focus. Themes were identified regarding the OR team members’ interactions with patients (calm, communication, comforting), with one another (teamwork, respect) and with the medical students (teaching). This classification of exemplary OR behaviour contributes to our understanding of how professional behaviour is viewed and potentially emulated by medical students on surgical rotations.
My worries are no longer behind me

First they make you drink something that tastes like slime - or British beer. Then you spend the majority of your day in the smallest room in your house. Then they stick a tube into you in a place normally discussed only in scatological humor. And after it's over, you spend the rest of the day producing as much natural gas as Kazakhstan. I've had more fun at faculty meetings.