2,107 research outputs found
The role of wind gusts in upper ocean diurnal variability
Upper ocean processes play a key role in air-sea coupling, with variability on both short and long time scales. The diurnal cycle associated with diurnal solar insolation and nighttime cooling, may act, along with stochastic wind variability, on upper ocean temperatures and stratification resulting in a diurnal warm layer and a nonlinear rectified effect on longer time scales. This study describes diurnal changes in upper ocean temperature for a location in the equatorial Indian Ocean, using observations from the Dynamics of the Madden-Julian Oscillation field campaign, a high vertical resolution 1-D process model, and a diurnal cycling scheme. Solar forcing is the main driver of diurnal variability in upper ocean temperature and stratification. Yet except during nighttime convection, winds with variability on the order of hours (here referred to as “wind gusts”) regulate how fast surface water is mixed to greater depths when daily mean winds are weak. Wind gusts are much stronger than diurnal winds. Even using stochastic wind gusts but no diurnal winds as input in a 1-D process model yields an estimate of diurnal temperature that compares well with observations. A new version of the Large and Caron (2015) scheme (LC2015) provides an estimate of upper ocean diurnal temperature that is consistent with observations. LC2015 has the advantage of being suitable for implementation in a climate model, with the goal to improve SST estimates, hence the simulated heat flux at the air-sea interface. Yet LC2015 is not very sensitive to the inclusion or omission of the high-frequency component of the wind
A schlieren method for ultra-low angle light scattering measurements
We describe a self calibrating optical technique that allows to perform
absolute measurements of scattering cross sections for the light scattered at
extremely small angles. Very good performances are obtained by using a very
simple optical layout similar to that used for the schlieren method, a
technique traditionally used for mapping local refraction index changes. The
scattered intensity distribution is recovered by a statistical analysis of the
random interference of the light scattered in a half-plane of the scattering
wave vectors and the main transmitted beam. High quality data can be obtained
by proper statistical accumulation of scattered intensity frames, and the
static stray light contributions can be eliminated rigorously. The
potentialities of the method are tested in a scattering experiment from non
equilibrium fluctuations during a free diffusion experiment. Contributions of
light scattered from length scales as long as Lambda=1 mm can be accurately
determined.Comment: 7 pages, 3 figure
Unwanted Publicity, the News Media, and the Constitution: Where Privacy Rights Compete With the First Amendment
It is ironic that while recent legal history records the emergence of a constitutional right to privacy, the Supreme Court, in a line of cases from New York Times to Firestone, has restricted the common law tort of privacy. The legal issues are particularly complex and admittedly difficult to reconcile when the public disclosure tort comes in conflict with first amendment privileges. Expansion of the privacy tort need not necessarily impose an unreasonable burden on the news media, provided the Supreme Court distinguishes between defamation and privacy invasion and establishes and applies to the latter wrong its own legal principles
Commentary on 'Improving the seasonal cycle and interannual variations of biomass burning aerosol sources' by Generoso et al.
In a recent published paper, Generoso et al. (2003) describe a method for improving the spatial and temporal distribution of pyrogenic aerosol emission inventories. In the course of their analysis, the authors note several significant discrepancies in the seasonality of burning as observed by the Visible and Infrared Scanner (VIRS) and four other biomass burning data sets derived from satellite observations. In this commentary we explain the source of these discrepancies and clarify the origin of the VIRS observations that were used by Generoso et al
A Theoretical Framework for Developing a National Transportation Strategy
Developing the surface transportation systems the United States needs will require asking and answering a series of questions, beginning with the most basic:What is the main purpose of surface transportation?What resources are available and what is the best way to deploy those resources?How do we measure success?Determining what future transportation systems should look like will require analyzing a range of economic, demographic, technological and socio-political variables.As management guru Peter Druker famously said, “The primary goal of every enterprise should be to create customers”. Transportation leaders must undertake the critical task of determining what transportation customers want and are willing to pay for. In doing so, they must understand that there are many categories of customers—such as commuters, businesses, and logistics companies—each with different priorities. Measurements of success should also be customer-focused.Finally, state departments of transportation—not their federal counterparts—are often best positioned to ask these questions and develop the right answers for their own states
Characterization of anisotropic nano-particles by using depolarized dynamic light scattering in the near field
Light scattering techniques are widely used in many fields of condensed and
sof t matter physics. Usually these methods are based on the study of the
scattered light in the far field. Recently, a new family of near field
detection schemes has been developed, mainly for the study of small angle light
scattering. These techniques are based on the detection of the light intensity
near to the sample, where light scattered at different directions overlaps but
can be distinguished by Fourier transform analysis. Here we report for the
first time data obtained with a dynamic near field scattering instrument,
measuring both polarized and depolarized scattered light. Advantages of this
procedure over the traditional far field detection include the immunity to
stray light problems and the possibility to obtain a large number of
statistical samples for many different wave vectors in a single instantaneous
measurement. By using the proposed technique we have measured the translational
and rotational diffusion coefficients of rod-like colloidal particles. The
obtained data are in very good agreement with the data acquired with a
traditional light scattering apparatus.Comment: Published in Optics Express. This version has changes in bibliograph
MicroRNA-551b expression profile in low and high-grade cervical intraepithelial neoplasia
OBJECTIVE: To evaluate the expression of microRNA (miR)-551b in patients with low and high grade cervical intraepithelial neoplasia (CIN) and to find an association with high-risk Human Papillomavirus (HR-HPV) infection-related prognostic biomarkers.
PATIENTS AND METHODS: The expression level of miR-551b was determined in 50 paraffin-embedded cervical specimens (10 normal squamous epithelium, 18 condylomas, 8 CIN1, and 14 CIN2-3) using quantitative Real-time polymerase chain reaction (qRT-PCR). χ2-test compared miR-551b expression in different diagnosis groups. An Ordered Logistic Regression and a Probit correlation were made to correlate miR-551b expression levels with the cervical tissue histological findings. The immunohistochemical distribution of p16 and Ki-67 according to histopathological findings was also assessed.
RESULTS: The distribution of the miR-551b expression profile was significantly lower in CIN1-3 samples compared to other histological diagnosis groups (condyloma and negative). The expression levels were inversely correlated to the cervical pathological grade, from negative to CIN2-3. A 1%
increase in miR-551b expression level produced an increase of 19% to the probability of a minor histological grade diagnosis in a range from negative
to CIN2-3 and an increase of 13% to the probability of a negative histological grade diagnosis. Among the cases with miR-551b expression < 0.02
(considered as cut-off value) a significant statistical correlation was found between p16 and Ki-67 expression and the diagnosis of CIN2-3.
CONCLUSIONS: O ur d ata s howed a s ignificant inverse correlation between miR-551b expression and the histological grading of the lesions,
suggesting a tumor suppressive function in the different stages of cervical dysplasia
Guiding of KeV Ions between Two Insulating Parallel Plates
Experimental data are presented for low-energy singly charged ion transport between two insulating parallel plates. Using a beam intensity of approximately 20 pA, measurements of the incoming and transmitted beams provide quantitative temporal information about the charge deposited on the plates and the guiding probability. Using a smaller beam intensity (~ 1 pA) plate charging and discharging properties were studied as a function of time. These data imply that both the charge deposition and decay along the surface and through the bulk need to be modeled as acting independently. A further reduction of beam intensity to ~ 25 fA allowed temporal imaging studies of the positions and intensities of the guided beam plus two bypass beams to be performed. SIMION software was used to simulate trajectories of the guided and bypass beams, to provide information about the amount and location of deposited charge and, as a function of charge patch voltage, the probability of beam guiding and how much the bypass beams are deflected plus to provide information about the electric fields. An equivalent electric circuit model of the parallel plates, used to associate the deposited charge with the patch voltage implies that the deposited charge is distributed primarily on the inner surface of the plates, transverse to the beam direction, rather than being distributed throughout the entire plate
Diverging neural dynamics for syntactic structure building in naturalistic speaking and listening
The neural correlates of sentence production have been mostly studied with constraining task paradigms that introduce artificial task effects. In this study, we aimed to gain a better understanding of syntactic processing in spontaneous production vs. naturalistic comprehension. We extracted word-by-word metrics of phrase-structure building with top-down and bottom-up parsers that make different hypotheses about the timing of structure building. In comprehension, structure building proceeded in an integratory fashion and led to an increase in activity in posterior temporal and inferior frontal areas. In production, structure building was anticipatory and predicted an increase in activity in the inferior frontal gyrus. Newly developed production-specific parsers highlighted the anticipatory and incremental nature of structure building in production, which was confirmed by a converging analysis of the pausing patterns in speech. Overall, the results showed that the unfolding of syntactic processing diverges between speaking and listening
Los nombres de los distritos de innovación
El nom juga un paper fonamental en la definició i la diferenciació d'una empresa dins d'una categoria. En aquest document identifiquem com els líders dels 7 districtes d'innovació (22@Barcelona, Ann Arbor Spark, EECi, Porto Digital, Ruta N – Medellín, SK-Skolkovo i TusPark) entenen la construcció dels noms dels seus districtes d'innovació. Adoptem un enfocament inductiu que utilitza dos tipus de dades: d’una banda, explorar la comprensió dels directors de districte d'innovació a través d'entrevistes semiestructurades directes i, d’altra banda, analitzar les dades secundàries que consisteixen en pàgines web i fullets. Demostrem com els líders dels districtes d'innovació utilitzen més d'un nom de classificació per a la seva organització i que aquests noms tendeixen a una postura més estratègica o institucional. Contribuïm ampliant la teoria de nomenclatura existent per incloure districtes d'innovació, una organització complexa composta per actors de la Triple Hèlix. També proporcionem ajut per a entendre la importància del paper del nom de la seva organització en el posicionament a llarg termini.Name plays a fundamental role in defining and differentiating a company within a category. In this paper we identify how the leaders of 7 innovation districts (22@Barcelona, Ann Arbor Spark, EECi, Porto Digital, Ruta N – Medellín, SK-Skolkovo and TusPark) understand the construction of the names of their innovation districts. We take an inductive approach utilizing two types of data: exploring the innovation district directors' understanding through direct semi-structured interviews and analyzing secondary data consisting of website and brochures. We show how innovation district leaders use more than one classification name for their organization and that these names either tend towards a more strategic or institutional posture. We contribute by extending existing naming theory to include innovation districts, a complex organization composed by actors of the Triple Helix. We also contribute by providing managerial guidance to assist in understanding the importance of the role of their organization's name in long-term positioning.El nombre juega un papel fundamental en definir y diferenciar una empresa dentro de una categoria. En este trabajo identificamos cómo los líderes de 7 distritos de innovación (22@Barcelona, Ann Arbor Spark, EECi, Porto Digital, Ruta N-Medellín, SK-Skolkovo, y TusPark) entienden la construcción de los nombres de sus distritos de innovación. Adoptamos un enfoque inductivo que utiliza dos tipos de datos: por un lado, la comprensión de los directores de distrito de innovación a través de entrevistes semiestructuradas directas y, por otro lado, el análisis de datos secundarios de páginas web y folletos publicitarios. Demostramos cómo los líderes de los distritos de innovación utilizan más de un nombre para clasificar su organización, y que estos nombres tienden a una postura más estratégica o institucional. Contribuimos ampliando la teoría de nomenclatura existente, para incluir distritos de innovación, una organización compleja compuesta por actores de la Triple Hélix. También proporcionamos ayuda para entender la importancia del papel que juega el nombre del distrito en su organización y en el posicionamiento en el largo plazo
- …