Effects of temporal envelope modulation on acoustic signal recognition in a vocal fish, the plainfin midshipman.

Amplitude modulation is an important parameter defining vertebrate acoustic communication signals. Nesting male plainfin midshipman fish, Porichthys notatus, emit simple, long duration hums in which modulation is strikingly absent. Envelope modulation is, however, introduced when the hums of adjacent males overlap to produce acoustic beats. Hums attract gravid females and can be mimicked with continuous tones at the fundamental frequency. While individual hums have flat envelopes, other midshipman signals are amplitude modulated. This study used one-choice playback tests with gravid females to examine the role of envelope modulation in hum recognition. Various pulse train and two-tone beat stimuli resembling natural communication signals were presented individually, and the responses compared to those for continuous pure tones. The effectiveness of pulse trains was graded and depended upon both pulse duration and the ratio of pulse to gap length. Midshipman were sensitive to beat modulations from 0.5 to 10 Hz, with fewer fish approaching the beat than the pure tone. Reducing the degree of modulation increased the effectiveness of beat stimuli. Hence, the lack of modulation in the midshipman's advertisement call corresponds to the importance of envelope modulation for the categorization of communication signals even in this relatively simple system.     

Pathwise uniqueness for reflecting Brownian motion in Euclidean domains

For a bounded C ^1,α domain in ℝ ^d we show that there exists a strong solution to the multidimensional Skorokhod equation and that weak uniqueness holds for this equation. These results imply that pathwise uniqueness and strong uniqueness hold for the Skorokhod equation. Received: 3 February 1999 / Revised version: 2 September 1999 /?Published online: 11 April 2000     

Efficient synthesis of fluorescent rosamines: multifunctional platforms for cellular imaging

Substituted rosamines are efficiently prepared through a new organometallic addition to an imine-substituted xanthone as a novel primary amine equivalent. The synthesis reduces the number of synthetic steps to the targeted rosamines, for convenient and facile access to potential libraries of rosamine dyes. The prepared rosamine derivatives represent unique multifunctional platforms that possess radiolabeling capability and fluorescence. Rosamines have (i) useful non-specific binding properties in mammalian cells and plant root hair, and (ii) positive uptake or binding properties in microbial systems.     

Multiscale mechanobiology modeling for surgery assessment

This paper discusses some of the concept of mod-eling surgery outcome. It is also an attempt to offer a roadmap for progress. This paper may serve as a common groundof discussion for both communities i.e surgeons and com-putational scientist in its broadest sense. Predicting surgeryoutcome is a very difficult task. All patients are different,and multiple factors such as genetic, or environment con-ditions plays a role. The difficulty is to construct modelsthat are complex enough to address some of these significantmultiscale elements and simple enough to be used in clini-cal conditions and calibrated on patient data. We will pro-vide a multilevel progressive approach inspired by two ap-plications in surgery that we have been working on. One isabout vein graft adaptation after a transplantation, the otheris the recovery of cosmesis outcome after a breast lumpec-tomy. This work, that is still very much in progress, mayteach us some lessons. We are convinced that the digital rev-olution that is transforming the working environment of thesurgeon makes closer collaboration between surgeons andcomputational scientist unavoidable. We believe that "com-putational surgery" will allow the community to develop pre-dictive model of the surgery outcome and greatprogresses insurgery procedures that goes far beyond the operating roomprocedural aspect.     

Effect of morphology of thin DNA films on the electron stimulated desorption of anions

We present a comparison between the electron stimulated desorption (ESD) of anions from DNA samples prepared by lyophilization (an example of poorly organized or nonuniform films) and molecular self-assembly (well-ordered films). The lyophilization (or freeze- drying) method is perhaps the most frequently employed technique for forming DNA films for studies of low-energy electron (LEE) interactions leading to DNA damage; however, this technique usually produces nonuniform films with considerable clustering which may affect DNA configuration and enhance sample charging when the film is irradiated. Our results confirm the general validity of ESD measurements obtained with lyophilized samples, but also reveal limitations of lyophilization for LEE studies on DNA films. Specifically we observe some modulation of structures, associated with dissociative electron attachment, in the anion yield functions from different types of DNA film, confirming that conformational factors play a role in the LEE induced damage to DNA.     

Orbital Reactions Through Space. Part III. Rate Enhancement in Epoxidation of an Olefin by a Proximate Hydroxyl Group

As part of a programme directed towards the synthesis of polycyclic systems containing a bicyclo[4.2.0]octa-2,4-diene moiety (or a potential precursor thereof) joined at the 7,8 position, suitable as substrates for the 1,2-photoarmatisation reaction¹, we sought a simple route to the epixide (5). We considered this offered the opening to prepare the 8-oxatricyclo-     

Detection of Tellurium in Presence of Extra Arsenic on Gold Electrodes Modified By Benzenedithiol Self‐Assembled Monolayers

Electrochemical detection of tellurium is interfered with arsenic due to their similar redox potentials. Gold electrodes modified by benzenedithiols (BDT) self‐assembled monolayers (SAMs) were explored to determine Te(IV) in the presence of extra As(III) in this work. SAMs of benzenedithiols on the gold surface allows for selective extraction of Te (IV) over As(III), while blocking the redox of As(III). It provides potential applications to tellurium toxicity analysis, biological membrane study and identification of geochemistry samples.     

Demonstration of a mode-conversion cavity add-drop filter

We experimentally demonstrate a new type of add-drop filter incorporating an asymmetric Y-branch waveguide coupler and a shifted-grating mode-conversion cavity. The device relies on mode separation in the asymmetric Y-branch and wavelength-selective mode conversion upon reflection from the shifted-grating cavity. Add-drop functionality is demonstrated in a three-port integrated silicon-on-insulator device.