cssi/SciSciGPT-SciSciNet huggingface dataset:
Examining plant uptake and translocation of emerging contaminants using machine learning: Implications to food security

When water and solutes enter the plant root through the epidermis, organic contaminants in solution either cross the root membranes and transport through the vascular pathways to the aerial tissues or accumulate in the plant roots. The accumulation of contaminants in plant roots and edible tissues is measured by root concentration factor (RCF) and fruit concentration factor (FCF). In this paper, 1) a neural network (NN) was applied to model RCF based on physicochemical properties of organic compounds, 2) correlation and significance of physicochemical properties were assessed using statistical analysis, 3) fuzzy logic was used to examine the simultaneous impacts of significant compound properties on RCF and FCF, 4) a clustering algorithm (k-means) was used to identify unique groups and discover hidden relationships within contaminants in various parts of the plants. The physicochemical cutoffs achieved by fuzzy logic for the RCF and the FCF were compared versus the cutoffs for compounds that crossed the plant root membranes and found their way into transpiration stream (measured by transpiration stream concentration factor, TSCF). The NN predicted the RCF with improved accuracy compared to mechanistic models. The analysis indicated that log Kow, molecular weight, and rotatable bonds are the most important properties for predicting the RCF. These significant compound properties are positively correlated with RCF while they are negatively correlated with TSCF. Comparing the relationships between compound properties in various plant tissues showed that compounds detected in the edible parts have physicochemical cutoffs that are more like the compounds crossing the plant root membranes (into xylem tissues) than the compounds accumulating in the plant roots, with clear relationships to food security. The cluster analysis placed the contaminants into three meaningful groups that were in agreement with the results of fuzzy logic.
Electrochemiluminescence (ECL)-Based Electrochemical Imaging Using a Massive Array of Bipolar Ultramicroelectrodes.

In this report, we describe the fabrication, characterization, and use of a massive array of closed bipolar ultramicroelectrodes (UMEs) in electrochemical imaging applications. The bipolar UME arra...
Paracrine Role for Somatostatin Interneurons in the Assembly of Perisomatic Inhibitory Synapses

GABAergic interneurons represent a heterogenous group of cell types in neocortex that can be clustered based on developmental origin, morphology, physiology, and connectivity. Two abundant populations of cortical GABAergic interneurons include the low-threshold, somatostatin (SST)-expressing cells and the fast-spiking, parvalbumin (PV)-expressing cells. While SST+ and PV+ interneurons are both early born and migrate into the developing neocortex at similar times, SST+ cells are incorporated into functional circuits prior to PV+ cells. During this early period of neural development, SST+ cells play critical roles in the assembly and maturation of other cortical circuits; however, the mechanisms underlying this process remain poorly understood. Here, using both sexes of conditional mutant mice, we discovered that SST+ interneuron-derived Collagen XIX, a synaptogenic extracellular matrix protein, is required for the formation of GABAergic, perisomatic synapses by PV+ cells. These results, therefore, identify a paracrine mechanism by which early-born SST+ cells orchestrate inhibitory circuit formation in the developing neocortex.SIGNIFICANCE STATEMENT Inhibitory interneurons in the cerebral cortex represent a heterogenous group of cells that generate the inhibitory neurotransmitter GABA. One such interneuron type is the low-threshold, somatostatin (SST)-expressing cell, which is one of the first types of interneurons to migrate into the cerebral cortex and become incorporated into functional circuits. In addition, to contributing important roles in controlling the flow of information in the adult cerebral cortex, SST+ cells play important roles in the development of other neural circuits in the developing brain. Here, we identified an extracellular matrix protein that is released by these early-born SST+ neurons to orchestrate inhibitory circuit formation in the developing cerebral cortex.
The Effect of Overexpression of Lrp5 on the Temporomandibular Joint.

ObjectiveThe temporomandibular joint (TMJ) is a unique fibrocartilaginous joint that adapts to mechanical loading through cell signaling pathways such as the Wnt pathway. Increased expression of lo...
Predicted Vitamin D Status and Colorectal Cancer Incidence in the Black Women's Health Study.

Background: Observational studies, mostly among White populations, suggest that low vitamin D levels increase colorectal cancer risk. African Americans, who are disproportionately burdened by colorectal cancer, often have lower vitamin D levels compared with other populations. Methods: We assessed predicted vitamin D score in relation to colorectal cancer among 49,534 participants in the Black Women9s Health Study, a cohort of African American women followed from 1995 to 2017 through biennial questionnaires. We derived predicted vitamin D scores at each questionnaire cycle for all participants using a previously validated prediction model based on actual 25-hydroxyvitamin D values from a subset of participants. We calculated cumulative average predicted vitamin D score at every cycle by averaging scores from cycles up to and including that cycle. Using Cox proportional hazards regression, we estimated hazard ratios (HR) and 95% confidence intervals (CI) for colorectal cancer incidence according to predicted score quartiles. Results: Over follow-up, 488 incident colorectal cancers occurred. Compared with women in the highest quartile of predicted vitamin D score, those in the lowest had an estimated 41% (HR = 1.41; 95% CI, 1.05–1.90) higher colorectal cancer risk. Comparable HRs were 1.44 (95% CI, 1.02–2.01) for colon and 1.34 (95% CI, 0.70–2.56) for rectal cancer. Conclusions: Low vitamin D status may lead to elevated colorectal cancer risk in African American women. Impact: Our findings, taken together with established evidence that vitamin D levels are generally lower in African Americans than other U.S. groups, suggest that low vitamin D status may contribute to the disproportionately high colorectal cancer incidence among African Americans.
Experimental Cerebral Edema, Isotonic Intravenous Infusions, Mannitol, Serum Osmolality, Electrolytes, Brain Water, Intracranial Pressure, and Cerebral Blood Flow

Mannitol and intravenous fluid resuscitation are therapies that are commonly employed in multiple trauma. Much discussion exists as to the correct dosage of mannitol, but the concomitant fluid resuscitation, mannitol and response to this agent, has received limited attention (James 1980). The current study addresses isotonic saline hydration, mannitol, ICP and CBF.
Pds5 regulators segregate cohesion and condensation pathways in Saccharomyces cerevisiae

Cohesins are required both for the tethering together of sister chromatids (termed cohesion) and subsequent condensation into discrete structures-processes fundamental for faithful chromosome segregation into daughter cells. Differentiating between cohesin roles in cohesion and condensation would provide an important advance in studying chromatin metabolism. Pds5 is a cohesin-associated factor that is essential for both cohesion maintenance and condensation. Recent studies revealed that ELG1 deletion suppresses the temperature sensitivity of pds5 mutant cells. However, the mechanisms through which Elg1 may regulate cohesion and condensation remain unknown. Here, we report that ELG1 deletion from pds5-1 mutant cells results in a significant rescue of cohesion, but not condensation, defects. Based on evidence that Elg1 unloads the DNA replication clamp PCNA from DNA, we tested whether PCNA overexpression would similarly rescue pds5-1 mutant cell cohesion defects. The results indeed reveal that elevated levels of PCNA rescue pds5-1 temperature sensitivity and cohesion defects, but do not rescue pds5-1 mutant cell condensation defects. In contrast, RAD61 deletion rescues the condensation defect, but importantly, neither the temperature sensitivity nor cohesion defects exhibited by pds5-1 mutant cells. In combination, these findings reveal that cohesion and condensation are separable pathways and regulated in nonredundant mechanisms. These results are discussed in terms of a new model through which cohesion and condensation are spatially regulated.
EDUCATION IN OKLAHOMA SINCE 1983

I returned to Oklahoma in 1983 after an absence of seventeen years. In the eighteen years since my return there has been, in some respects, substantial change, not all for the better. In many ways Oklahoma is a good place to live. The climate, though brutal in August, allows me to ride my motorcycle at least eleven months a year. The state's scenery, though not spectacular, provides a wide variety of enjoyable vignettes. The new canal and Bricktown in general bring vitality and a cosmopolitan aura to the capital city. Arcadia and similar parks are essential oases in an otherwise arid prairie landscape. The Cowboy Hall of Fame, Zoo and some other improved facilities contribute significantly to the quality of life.
Differential Access to Housing in the Suburbs.

The suburbanization of racial and ethnic groups may be viewed within the context of ecological theory. Implicit in ecological theory is that a group's social and economic status strongly influences its ability to obtain access to housing within the suburbs of metropolitan areas. According to theorists of human ecology, group variation in suburbanization relates directly to measurable differences on social and economic variables (Burgess, 1923; Park, 1926). Thus low-status groups are likely to be less suburbanized than higher-status groups. Insofar as ensuing patterns of location are a function of the differences in the social and economic positions of racial and ethnic groups, these patterns tell us something about the nature of the populations involved. This led Park (1952, p. 177) to conclude that social relations are inevitably correlated with spatial relations and physical distance with social distance. Led by this assumption, most past studies of racial and ethnic groups have viewed the residential patterns of such groups as a significant element in the study of their assimilation. They have, therefore, assessed the extent to which each foreign-born group was living in the same residential areas as the native-White population (Lieberson, 1963, p. 11). Most members of the latter group presently live in suburbs. Studies of the residential patterns of racial and ethnic groups have traditionally focused on the foreign-born White populations from southern and eastern Europe (e.g. Kantrowitz, 1973; Lieberson, 1963), or the native-born Black population (Sears & Faytell, 1974; Taeuber, 1964, 1965). Only recently have the resi-
Robust speech processing using ARMA spectrogram models

Speech applications in noisy and degraded channel conditions continue to be a challenging problem especially when there is a mismatch between the training and test conditions. In this paper, a robust speech feature extraction scheme is developed based on autoregressive moving average (ARMA) modeling that emphasizes high energy regions of the signal with a data driven modulation filter. The peak preserving ability of two dimensional autoregressive (AR) models is used to emphasize the high energy regions in the spectrotemporal domain. The modulation filtering property is achieved by moving average (MA) modeling. The ARMA spectrograms are used to derive features for speech recognition in the Aurora-4 database. In these experiments, the ARMA model features provide significant improvements (relative improvements of 15%) compared to other robust features. Furthermore, the robustness of these features is also verified for language identification (LID) of highly degraded radio channel speech. Here, the ARMA approach achieves relative improvements of up to 20% over the baseline features.
On the Role of Glial Cells in the Mammalian Nervous System UPTAKE, EXCRETION, AND METABOLISM OF PUTATIVE NEUROTRANSMITTERS BY CULTURED GLIAL TUMOR CELLS

Abstract The synthesis, uptake, and efflux of some putative neurotransmitters by cultured rat glial tumor cells were studied. Three glial cell clones were capable of pyridoxal-dependent synthesis of γ-aminobutyrate both in cell-free homogenates and in intact cells in monolayers. Substantial catabolism of γ-aminobutyrate was not found. Synthesis of taurine and isethionic acid, but not β-alanine, by one of the glioma lines was also shown. Glioma lines were found to take up glutamate and exhibited Na+-dependent uptake of γ-aminobutyrate. The uptake of γ-aminobutyrate consisted of a slow saturable component (Kt ∼ 13 to 30 µm) and a rapid nonsaturable component. Both of these were antagonized by some structural analogs of γ-aminobutyrate as well as by taurine, β-alanine, bicuculline, and low temperature. Similar kinetic parameters were found for three different glioma lines. Fibroblast-like cells obtained from rat brain cell cultures had only the nonsaturable component of γ-aminobutyrate uptake. Taurine uptake also consisted of two Na+-dependent and temperature-dependent components: a rapid saturable component (Kt ∼ 10 to 17 µm) and a nonsaturable component which varied in magnitude between cell lines. These uptakes were antagonized by β-alanine but not by γ-aminobutyrate. The glioma lines also excreted the concentrated γ-aminobutyrate into the extracellular milieu, but could maintain cell to medium concentration ratios of g80-fold. In taurine efflux experiments, cell to medium concentration ratios in excess of 1500-fold could be maintained by one of the gliomas. The data are consistent with a possible role of central nervous system glial cells in the modulation of neuronal excitability via control of the levels of neuroactive substances in the extracellular milieu of neurons.
A code for line blanketing without local thermodynamic equilibrium.

A numerical code has been written which is designed to calculate radiation transport and atmospheric structure under the constraints of statistical equilibrium in atomic transitions and radiative and hydrostatic equilibrium in the medium. In addition to the complete linearization and variable Eddington factor techniques of Auer and Mihalas, it uses a multi-frequency / multi-grey algorithm which admits the inclusion of many spectral lines in full statistical equilibrium. The program can comfortably accept up to about 300 specific lines arising from about 30 lower states and any number of continua. Cleverly constructed artificial model atoms can extend the number of lines to 3000 or more, where opacity sampling techniques can begin to approximate the blanketing accomplished by Kurucz in LTE. By way of example, I present a model of a stellar atmosphere with effective temperature 35,000 K and surface gravity 104 cm s-2. The calculation includes 98 bound-free transitions and 93 bound-bound transitions (57 with radiative rates) between 91 states in 36 ions of 9 cosmically abundant species.
Electrical breakdown in transformer oil

Summary form only given. The fundamental breakdown physics of transformer oils is investigated with high-speed electrical and optical diagnostics with temporal resolution down to 500 ps. Univolt 63 and Envirotemp FR3 (biodegradable) are used for this study. The system set up employs a cable discharge into a coaxial system with point/plane axial discharge and load line to providing a matched terminating impedance. Overall, the impedance of the system is matched at 50 ohms throughout with the exception of the very narrow gap region and includes a 50 ohm load resistor terminating the load line. Self breakdown is achieved by applying up to 50 kV to the charging line. Pulsed breakdown is achieved by charging a pulse forming line with a two way transient time of 300 ns, up to 100 kV. The pulse forming line is then fed into the discharge line via an oil spark gap. Transmission line type current sensors and a capacitive voltage divider with fast amplifiers/attenuators are used in order to attain a complete range of information from amplitudes of 0.1 mA to 1 kA with temporal resolutions of 300 ps. Optical measurements are performed on low level light emission using fast photo-multiplier tubes (risetime of 800 ps) spatially resolved, supplemented with high speed and spectroscopic investigations on a nanosecond timescale. Breakdown voltages at gap distances of 5 mm for pre, self, and pulsed breakdown voltages are given, where breakdown with negative needle tips show 20% higher breakdown voltages than the ones with positive needle. Velocities of propagating "tree"-structures for the pre and self-breakdown are a few km/s while pulsed breakdown velocities are several 10's of km/s, with higher velocities for a negative needle. The trees have to reach the opposite electrode before full breakdown occurs. Simultaneous optical measurements for a single breakdown event are presented, such as the luminosity in comparison to shadowgraphy images, which is necessary to describe the complex interaction of hydrodynamic phenomena (channel and tree formation and propagation) and charge carrier multiplication.
IT'S 10 p.m., DO YOU KNOW WHERE YOUR CHILDREN ARE?

Over the past several decades, parent-child abduction has turned from a national into an international problem. To try and minimize this problem, The Hague Convention on the Civil Aspects of International Child Abduction was adopted on October 1980. The goal of the Convention is to ensure that abducted children are promptly returned to their homes. While the goal has been met, the overwhelming use of the Convention's exceptions must be limited so that the purpose of the Convention is not damaged.
Use of artificial neural networks for real-time prediction of heave displacement in ocean buoys

Many advanced control systems for wave energy converters (WEC's) require knowledge of incoming wave profiles to be implemented. This is due to the non-causal relationship between water elevation and force exerted on a floating body. This study focuses on the use of cascade feedforward neural networks to predict short-term incoming water surface displacements based on recently observed data in real time. Prediction networks are trained with time series data reconstructed from spectral data and recorded time series data from a data buoy deployed off the West Irish Coast. Both training methods are shown to have predictive capabilities with regression coefficients between 0.8–0.9 for a small range of sea states. Both networks prediction accuracies are tested on a large range of sea states as well. For sea states dramatically different from training data prediction accuracies decrease, but less so for the network trained on observed data. The need for accurate wave predictions in the field of WEC control design is also discussed.
Biologically engineered microstructures: controlled release applications

The area of self-assembled ultrafine particulate-based composites (nano composites) has been a major thrust in advanced material development. In this paper we report on the application of biologically derived, self-assembled cylindrical microstructures to form advanced composite materials for controlled release applications. These microstructures (we call them tubules) have many applications in the material sciences. This paper will focus on the potential for rationally controlling the fabrication of submicron microstructures for controlled release applications.
Operating reserve requirements in a power system with dispersed wind generation

Operation of the power systems with high wind penetration is significantly influenced by wind variability and uncertainty. This paper examines the potential impact of distributed wind generation on operating reserve requirements in the IEEE 24-bus system. Wind and load are stochastically modeled using actual data from a balancing authority. Probabilistic optimal power flow based on the two point estimate method is used to determine the reserve required to compensate for the variable wind power output. The proposed method considers stochastic factors and their affects on the dispatch results. Different scenarios are studied to evaluate dispersed wind generation and its potential to reduce the reserve requirement and transmission congestion cost. Correlation between the power outputs of different wind farms and wind penetration level are considered as determining factors when choosing wind sites for distributed generation. The effect of this factor on the operating reserve requirement is assessed in this paper. A brief study is also carried out regarding the transmission congestion cost and the potential reduction of this cost due to dispersed wind generation.
Analysis, simulation and fabrication of curved multimorphs that undergo bending and twisting

Difference in strain in the layers of a multimorph produces deformation. Unlike straight multimorphs that bend, curved multimorphs undergo both bending and twisting. The small deformation analysis of curved multimorphs is reported and validated against simulations and experiments.
Clinical practice. Long-QT syndrome.

After a 13-year-old girl dies suddenly while playing basketball, her family comes to the clinic for medical evaluation. Her parents' resting electrocardiograms (ECGs) are normal, but her 9-year-old sister's ECG has an abnormally long QT interval. The family history is notable for recurrent syncope in the maternal grandmother's female relatives. How should family members be evaluated and treated?
The Relationship Between Drinking Patterns At Therapy Termination And Intake And Termination Status On Social Variables: A Replication Study

The interpersonal support, residence, and employment status of 198 alcoholics were assessed both at intake and at therapy termination. At question was the comparative strength of association between the social status variables when assessed at intake versus termination with drinking patterns at termination of therapy. Results indicated the magnitude of association was very high for termination social variables and minimal to nonexistent for intake social variables. The study was replicated with a group of 171 alcoholics with virtually identical results. The implications of these results for assessing alcohol treatment outcomes are discussed.
Polyomavirus Large T Can Support DNA Replication in Human Cells

Abstract Human cells are generally thought to be nonpermissive for polyomavirus (Py) DNA replication. Using transient transfection, we show that Py large T-antigen (LT) was able to support replication of a Py origin-containing plasmid in two human cell lines. Replication supported by LT in human cells was specific for the Py origin and required its enhancer sequences, as well as the previously reported critical phosphorylation sites within LT. Py replication efficiency was comparable to that of papillomavirus E1- and E2-activated DNA replication in transient assays performed in human 293 and C-33A cells. Previous analysis of DNA replication in vitro has pointed to polymerase α–primase as a specificity determinant for polyomavirus. The data presented here imply that in certain cellular environments, Py LT must functionally interact with human polymerase α–primase to permit DNA replication.
Chronic arthritis of rabbits induced by mycoplasmas. II. Antibody response and the deposition of immune complexes.

Chronic mycoplasma-induced arthritis of rabbits was accompanied by a highly active humoral immune response. Peak antibody liters coincided with the “disappearance” of mycoplasmas from joint tissues at 7 weeks. High synovial fluid antibody liters and immuno-globulin-producing cells in frozen sections of synovial membrane suggested local antibody production. Persistence of granular deposits containing IgG and complement in synovium and cartilage may be a mechanism for continuing inflammation in the apparent absence of cultivable mycoplasmas.
Asian Americans and campaign finance in municipal elections

Abstract This paper explores the political significance of Asian American campaign finance activity in municipal elections. We examined both the donation patterns of Asian contributors and the fundraising coalitions assembled by Asian candidates. From the contributor perspective, we found that Asians contributed in roughly proportional levels to their population as a whole, and were willing to contribute not only to coethnics but also to Asian candidates of other ethnicities and to non-Asians. As for Asian candidates, we found that they relied heavily on Asian contributors for campaign funds, especially coethnics. Asian candidates’ ability to draw on ethnic networks for campaign funds is an important political resource that enhances their ability to mount competitive campaigns. However, the value of these networks is limited by candidates’ inability or unwillingness to form panethnic fundraising coalitions.
Spinothalamic lamina I neurones selectively responsive to cutaneous warming in cats

1. In order to further characterize the role of lamina I as the source of central ascending neural pathways for thermoreception and thermoregulation, experiments were performed on anaesthetized cats to determine the quantitative response characteristics of warming-specific lumbosacral spinothalamic lamina I neurones. 2. We identified 10 neurones out of 474 that were selectively excited by cutaneous warming (Warm cells). Their thresholds were all in the range 35-37 degrees C at a baseline of 34.5 degrees C, and their discharge linearly encoded the temperature of graded, innocuous warming stimuli with a sensitivity of 2.1 Hz x degrees C(-1). 3. The stimulus-response function of the Warm cells plateaued at temperatures that were in the noxious heat range. 4. The Warm cells were distinguished from other classes of spinothalamic lamina I neurones by their peripheral inputs, central conduction velocities and level of ongoing activity. 5. The discharge of Warm cells compares well with the known human psychophysics of warm sensibility, and these neurones are likely to be crucial to discriminative thermoreception. Additionally, a role in thermoregulation, a defining feature of mammalian homeostasis, is suggested.
Recurrent chlamydial colonization during pregnancy.

To evaluate the prevalence of and associated factors for recurrent Chlamydia trachomatis infection in pregnant women, a retrospective cohort study was conducted in an urban prenatal clinic in an underserved area. Women with chlamydial carriage in pregnancy between 1992 and 1996 were identified by a direct DNA assay. Entrance criteria limited the population to those who were positive for chlamydia, were treated, had proof of cure and had at least one subsequent test for chlamydia, all in the same pregnancy. Of the 149 women who met entrance criteria, 25 (1 7%) had recurrent chlamydial carriage. The only identified risk factor was maternal age <20 years (21 of 98 vs. 4 of 51, odds ratio = 3.21). Infection with gonorrhea or other sexually transmitted diseases during the same pregnancy were not predictive of reinfection. Initial therapy with azithromycin, when compared to erythromycin, did not appear protective for recurrent infection. Pregnant adolescents are more likely to have recurrent chlamydial infection. Prenatal care programs should consider this when counseling and treating these patients.
Coding in the Partial Order of Enumerable Sets

Abstract We develop methods for coding with first-order formulas into the partial order E of enumerable sets under inclusion. First we use them to reprove and generalize the (unpublished) result of the first author that the elementary theory of E has the same computational complexity as the theory of the natural numbers. Relativized versions of the coding methods show that the p.o. of Σ 0 p and Σ 0 q sets are not elementarily equivalent for natural numbers p ≠ q . As a further application, definability of the class of quasimaximal sets in E is obtained. On the other side, we prove theorems limiting coding and definability in E , thereby establishing a sharp contrast between E and other structures occurring in computability theory.
Discovering functional relationships between RNA expression and chemotherapeutic susceptibility using relevance networks

In an effort to find gene regulatory networks and clusters of genes that affect cancer susceptibility to anticancer agents, we joined a database with baseline expression levels of 7,245 genes measured by using microarrays in 60 cancer cell lines, to a database with the amounts of 5,084 anticancer agents needed to inhibit growth of those same cell lines. Comprehensive pair-wise correlations were calculated between gene expression and measures of agent susceptibility. Associations weaker than a threshold strength were removed, leaving networks of highly correlated genes and agents called relevance networks. Hypotheses for potential single-gene determinants of anticancer agent susceptibility were constructed. The effect of random chance in the large number of calculations performed was empirically determined by repeated random permutation testing; only associations stronger than those seen in multiply permuted data were used in clustering. We discuss the advantages of this methodology over alternative approaches, such as phylogenetic-type tree clustering and self-organizing maps.
Corrigendum for “Energy balance for viscoelastic bodies in frictionless contact”

The proof in "Energy balance for viscoelastic bodies in frictionless contact" of an energy balance has a crucial flaw that renders the proof incorrect. At present no correction for this flaw is known.
A hybrid model for the acoustic response of a two-dimensional rough surface to an impulse incident from a refracting medium

Abstract A numerical model to calculate the impulse response of a two-dimensional, impenetrable, rough surface directly in the time domain has been recently introduced [J. Acoust. Soc. Am. (2000) 107, 27]. This model is based on wedge diffraction theory and assumes that the half-space containing the source and receiver is homogeneous. In this work, the model is extended to handle media where the index of refraction varies with the distance to the surface by merging the scattering model with a ray-based propagation model. The resulting hybrid model is tested against a Finite-Difference Time-Domain (FDTD) method for the problem of backscattering from a corrugated surface in the presence of a refractive layer. This new model can be applied, for example, to calculate acoustic reverberation from the sea surface in cases where the water mass is inhomogeneous and in the presence of a subsurface bubble layer at low frequencies where dispersion is negligible. It can also be used for atmospheric propagation problems where there is a sound speed gradient overlying rough terrain.
MicroRNAs: regulators of neuronal fate

Mammalian neural development has been traditionally studied in the context of evolutionarily conserved signaling pathways and neurogenic transcription factors. Recent studies suggest that microRNAs, a group of highly conserved noncoding regulatory small RNAs also play essential roles in neural development and neuronal function. A part of their action in the developing nervous system is to regulate subunit compositions of BAF complexes (ATP-dependent chromatin remodeling complexes), which appear to have dedicated functions during neural development. Intriguingly, ectopic expression of a set of brain-enriched microRNAs, miR-9/9* and miR-124 that promote the assembly of neuron-specific BAF complexes, converts the nonneuronal fate of human dermal fibroblasts towards postmitotic neurons, thereby revealing a previously unappreciated instructive role of these microRNAs. In addition to these global effects, accumulating evidence indicates that many microRNAs could also function locally, such as at the growth cone or at synapses modulating synaptic activity and neuronal connectivity. Here we discuss some of the recent findings about microRNAs’ activity in regulating various developmental stages of neurons.
Toward a Calculus of Concepts

By concepts will be meant propositions (or truth-values), attributes (or classes), and relations of all degrees. The degree of a concept will be said to be 0, 1, or n (> 1), and the concept will be said to be medadic, monadic, or n-adic, according as the concept is a proposition, an attribute, or an n-adic relation. The common procedure in systematizing logistic is to treat these successive degrees as ultimately separate categories. The partition is not rested upon properties of the thus classified elements within the formal system, but is imposed rather at the metamathematical level, through stipulations as to what combinations of signs are to be accorded or denied meaning. Each function of the formal system is restricted, thus metamathematically, to one degree for its values and to one for each of its arguments. The theory of types imports a further scheme of infinite partition, imposed by metamathematical stipulations as to the relative types of admissible arguments of the several functions and stipulations as to the types of the values of the functions relative to the types of the arguments.The elaborateness of the metamathematical grillwork which thus underlies formal logistic accounts in part for the tendency of those interested in logistic less for the matters treated than for the structures exemplified to limit their attention to the propositional calculus and the Boolean calculus of attributes (or classes), which, taken separately, are independent of the partitioning. A second reason for the algebraic appeal of these departments is their freedom from bound (apparent) variables: for use of bound variables fuses systematic considerations with notational or metamathematical ones in a way which resists ordinary formulation in terms of fixed functions and their arguments. Freedom from bound variables may be regarded, indeed, as the feature distinguishing algebra from analysis.
Latex anaphylaxis: Report of occurrence in two pediatric surgical patients and review of the literature

This report describes two cases of intraoperative anaphylaxis in children sensitized to latex. Both children were undergoing nonurological procedures and, despite numerous previous operations, neither had a history of unusual reaction or anaphylaxis during surgery. The problem of latex allergy is discussed with review of the current literature and suggestions for management.
Flux-dependent transmission of supercoiled plasmid DNA through ultrafiltration membranes

Abstract Although previous studies have demonstrated the potential of using membrane-based processes for purification of plasmid DNA, there is considerable discrepancy regarding both the physical mechanisms governing DNA transmission and the effects of membrane pore size and operating conditions on the DNA sieving coefficient. The objective of this work was to obtain quantitative data on the transmission of a 3.0 kbp supercoiled plasmid DNA through Ultracel ultrafiltration membranes with different nominal molecular weight cut-offs over a range of filtrate flux. The extent of plasmid transmission was a very strong function of the filtrate flux, with the sieving coefficient increasing from essentially zero to nearly one as the flux increased. Data were analyzed in terms of available filtration models to examine the contributions of DNA elongation, shear deformation, and concentration polarization on the observed plasmid transmission. The results clearly indicate the importance of flow-induced elongation or deformation on DNA transmission, with the data consistent with a modified version of the elongational flow model using the plasmid superhelix radius as the characteristic dimension. The results provide important insights into the factors controlling DNA transmission through semipermeable ultrafiltration membranes.
Photo-induced antiferromagnetic interlayer coupling in Fe superlattices with iron silicide spacers (invited)

Sputtered Fe/FeSi films possessing antiferromagnetic (AF) interlayer coupling at room temperature develop ferromagnetic remanence when cooled below 100 K, but the AF coupling can be restored at low temperature by exposure to visible light of sufficient intensity (≳10 mW/mm2). We attribute these effects to charge carriers in the FeSi spacer layer, which, when thermally or photogenerated, are capable of communicating spin information between the Fe layers.
Estimating subpixel surface temperatures and energy fluxes from the vegetation index-radiometric temperature relationship

Routine (i.e., daily to weekly) monitoring of surface energy fluxes, particularly evapotranspiration (ET), using satellite observations of radiometric surface temperature has not been feasible at high pixel resolution (i.e., ∼101–102 m) because of the low frequency in satellite coverage over the region of interest (i.e., approximately every 2 weeks). Cloud cover further reduces the number of useable observations of surface conditions resulting in high-resolution satellite imagery of a region typically being available once a month, which is not very useful for routine ET monitoring. Radiometric surface temperature observations at ∼1- to 5-km pixel resolution are available multiple times per day from several weather satellites. However, this spatial resolution is too coarse for estimating ET from individual agricultural fields or for defining variations in ET due to land cover changes. Satellite data in the visible and near-infrared wavelengths, used for computing vegetation indices, are available at resolutions an order of magnitude smaller than in the thermal-infrared, and hence provide higher resolution information on vegetation cover conditions. A number of studies have exploited the relationship between vegetation indices and radiometric surface temperature for estimating model parameters used in computing spatially distributed fluxes and available moisture. In this paper, the vegetation index–radiometric surface temperature relationship is utilized in a disaggregation procedure for estimating subpixel variation in surface temperature with aircraft imagery collected over the US Southern Great Plains. The disaggregated surface temperatures estimated by this procedure are compared to actual observations at this subpixel resolution. In addition, a remote sensing-based energy balance model is used to compare output using actual versus estimated surface temperatures over a range of pixel resolutions. From these comparisons, the utility of the surface temperature disaggregation technique appears to be most useful for estimating subpixel surface temperatures at resolutions corresponding to length scales defining agricultural field boundaries across the landscape.
Molecular genetics for paediatric surgeons

Abstract Molecular genetic techniques have transformed the understanding of the development of tumours. Some important concepts and facts are illustrated in this brief review. A good example from developmental biology are the master control genes, the Hox genes. Mutation analysis work on drosophila in the 1980s confirmed the presence of axial control genes. Genetic techniques later applied to xenopus and rodents showed that animals share these and other homologous genes and developmental mechanisms. Axial specification is outlined because of its historic and biological importance. The genetics of some common and some rare (but illustrative) conditions are then summarized. Advances in the biology of neuroblastomas is used to illustrate the importance of the application of genetic techniques to tumours. The human genome is mapped and it is expected that the use of recombinant DNA technology, antisense agents and transgenic techniques will lead to a better understanding of the genetic control of development, the pathogenesis of congenital anomalies and the characterization of tumour biology.
A robust data-driven approach for gene ontology annotation

Gene ontology (GO) and GO annotation are important resources for biological information management and knowledge discovery, but the speed of manual annotation became a major bottleneck of database curation. BioCreative IV GO annotation task aims to evaluate the performance of system that automatically assigns GO terms to genes based on the narrative sentences in biomedical literature. This article presents our work in this task as well as the experimental results after the competition. For the evidence sentence extraction subtask, we built a binary classifier to identify evidence sentences using reference distance estimator (RDE), a recently proposed semi-supervised learning method that learns new features from around 10 million unlabeled sentences, achieving an F1 of 19.3% in exact match and 32.5% in relaxed match. In the post-submission experiment, we obtained 22.1% and 35.7% F1 performance by incorporating bigram features in RDE learning. In both development and test sets, RDE-based method achieved over 20% relative improvement on F1 and AUC performance against classical supervised learning methods, e.g. support vector machine and logistic regression. For the GO term prediction subtask, we developed an information retrieval-based method to retrieve the GO term most relevant to each evidence sentence using a ranking function that combined cosine similarity and the frequency of GO terms in documents, and a filtering method based on high-level GO classes. The best performance of our submitted runs was 7.8% F1 and 22.2% hierarchy F1. We found that the incorporation of frequency information and hierarchy filtering substantially improved the performance. In the post-submission evaluation, we obtained a 10.6% F1 using a simpler setting. Overall, the experimental analysis showed our approaches were robust in both the two tasks.
Palaeoenvironmental trends in the history of trace fossils

Tracks, trails and burrows made by organisms are commonly preserved in Phanerozoic sedimentary rocks. These biogenic sedimentary structures, or trace fossils, have been most intensively studied from rocks deposited in marine environments, and have proven to be extremely useful in palaeoenvironmental reconstruc-tions. Our systematic analysis of occurrences in the stratigraphic record of two of the most common trace fossils, Zoophycos and Ophiomorpha, indicates that occurrences for each show an environmentally linked directional pattern through time. Zoophycos is commonly reported from Palaeozoic strata deposited from nearshore to deep-sea environments, whereas in post-Palaeozoic stratait is generally reported only from rocks deposited in deeper-water environments. Ophiomorpha first appeared in Permian shallowwater environments and was common in deep-sea fan environments by the Cretaceous, and has been distributed from nearshore to deep-sea environments since then. These onshore-offshore trends, which are similar to those previously reported for Phanerozoic benthic macroinvertebrate assemblages and individual higher taxa, require integration into future palaeoenvironmental reconstructions that use trace fossils.
A non-invasive prediction model for non-alcoholic steatohepatitis in paediatric patients with non-alcoholic fatty liver disease

Background Non-alcoholic fatty liver disease encompasses a spectrum of diseases that range from simple steatosis to the aggressive form of non-alcoholic steatohepatitis. Non-alcoholic steatohepatitis is currently diagnosed through liver biopsy. Aim To develop a non-invasive predictive model of non-alcoholic steatohepatitis in children with non-alcoholic fatty liver disease. Methods Anthropometric, laboratory, and histologic data were obtained in a cohort of children with biopsy-proven non-alcoholic fatty liver disease. Multivariable logistic regression analysis was employed to create a nomogram predicting the risk of non-alcoholic steatohepatitis. Internal validation was performed by bootstrapping. Results Three hundred and two children were included in this analysis with a mean age of 12.3 ± 3.1 years, a mean body mass index percentile of 94.3 ± 6.9, and non-alcoholic steatohepatitis was present in 67%. Following stepwise variable selection, total cholesterol, waist circumference percentile, and total bilirubin were included as variables in the model, with good discrimination with an area under the receiver operating characteristic curve of 0.737. Conclusions A nomogram was constructed with reasonable accuracy that can predict the risk of non-alcoholic steatohepatitis in children with non-alcoholic fatty liver disease. If validated externally, this tool could be utilized as a non-invasive method to diagnose non-alcoholic steatohepatitis in children with non-alcoholic fatty liver disease.
Fluid-structure interaction of submerged floating tunnel in wave field

The aspect ratio of submerged floating tunnel (SFT), i.e. the ratio of length to diameter, is usually as large as 102 to 103, which means the behavior of SFT would like a slender cylinder restrained by tethers. Although SFT is usually placed under the water surface at a certain depth, surface wave has important influence on its dynamic response due to the slenderness. This paper performs analyses on the fluid-structure interaction of SFT in wave field. Potential fluid theory is adopted to describe the wave field. Boundary element method is used to solve the interaction between SFT and surface wave. Wave potential is divided into three parts, including incident wave potential, diffraction wave potential and radiation wave potential. SFT is discretized into finite elements and its dynamic response is finally solved in frequency domain. As a case study, the values of design parameters for SFT prototype in Qiandao Lake are adopted. Two different tunnel end connectors are used to compare the distributions of tunnel deflections, axial membrane forces at the tube segment connectors and tunnel end connectors.
Origin of the Genus Homo

The origin of the genus Homo in Africa signals the beginning of the shift from increasingly bipedal apes to primitive, large-brained, stone tool-making, meat-eaters that traveled far and wide. This early part of the human genus is represented by three species: Homo habilis, Homo rudolfensis, and Homo erectus. H. habilis is known for retaining primitive features that link it to australopiths and for being the first stone tool makers. Little is known about H. rudolfensis except that it had a relatively large brain and large teeth compared to H. habilis and that it overlapped in time and space with other early Homo. Our understanding of the paleobiology and evolution of the larger-brained H. erectus is enhanced due to its rich fossil record. H. erectus was the first obligate, fully committed biped, and with a body adapted for modern striding locomotion, it was also the first in the human lineage to disperse outside of Africa. The early members of the genus Homo are the first to tip the scale from the more apish side of our evolutionary history toward the more human one.
A perturbation theory

Abstract We present a perturbation theory for obtaining solutions to Hamiltonian dynamical systems. This theory is based on Hamilton's principle and can be used to analytically solve perturbed two point boundary value and initial value problems. Applications include orbit transfers, optimal control problems and low-energy spacecraft mission design. Examples showing the validity of the theory is presented.