Modeling natural sounds with modulation cascade processes

Natural sounds are structured on many time-scales. A typical segment of speech, for example, contains features that span four orders of magnitude: Sentences ($\sim1$s); phonemes ($\sim10$−$1$ s); glottal pulses ($\sim 10$−$2$s); and formants ($\sim 10$−$3$s). The auditory system uses information from each of these time-scales to solve complicated tasks such as auditory scene analysis [1]. One route toward understanding how auditory processing accomplishes this analysis is to build neuroscience-inspired algorithms which solve similar tasks and to compare the properties of these algorithms with properties of auditory processing. There is however a discord: Current machine-audition algorithms largely concentrate on the shorter time-scale structures in sounds, and the longer structures are ignored. The reason for this is two-fold. Firstly, it is a difficult technical problem to construct an algorithm that utilises both sorts of information. Secondly, it is computationally demanding to simultaneously process data both at high resolution (to extract short temporal information) and for long duration (to extract long temporal information). The contribution of this work is to develop a new statistical model for natural sounds that captures structure across a wide range of time-scales, and to provide efficient learning and inference algorithms. We demonstrate the success of this approach on a missing data task.

Self-assembled multilayer graphene oxide membrane and carbon nanotubes synthesized using a rare form of natural graphite

The fabrication of flexible multilayer graphene oxide (GO) membrane and carbon nanotubes (CNTs) using a rare form of high-purity natural graphite, vein graphite, is reported for the first time. Graphite oxide is synthesized using vein graphite following Hummer's method. By facilitating functionalized graphene sheets in graphite oxide to self-assemble, a multilayer GO membrane is fabricated. Electric arc discharge is used to synthesis CNTs from vein graphite. Both multilayer GO membrane and CNTs are investigated using microscopy and spectroscopy experiments, i.e., scanning electron microscopy (SEM), atomic force microscopy (AFM), high-resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), core level photoelectron spectroscopy, and C K-edge X-ray absorption spectroscopy (NEXAFS), to characterize their structural and topographical properties. Characterization of vein graphite using different techniques reveals that it has a large number of crystallites, hence the large number of graphene sheets per crystallite, preferentially oriented along the (002) plane. NEXAFS and core level spectra confirm that vein graphite is highly crystalline and pure. Fourier transform infrared (FT-IR) and C 1s core level spectra show that oxygen functionalities (-C-OH, -CO,-C-O-C-) are introduced into the basal plane of graphite following chemical oxidation. Carbon nanotubes are produced from vein graphite through arc discharge without the use of any catalyst. HRTEM confirm that multiwalled carbon nanotube (MWNTs) are produced with the presence of some structure in the central pipe. A small percentage of single-walled nanotubes (SWNTs) are also produced simultaneously with MWNTs. Spectroscopic and microscopic data are further discussed here with a view to using vein graphite as the source material for the synthesis of carbon nanomaterials. © 2013 American Chemical Society.

Natural frequency and damping ratio of a vertically vibrated surface foundation

It is possible and common to obtain equivalent natural frequency and damping for a soil-foundation system from results of experimental or numerical analysis assuming the system has a single degree of freedom. Three approaches to extract natural frequency and damping were applied to the vertically vibrated soil-foundation system. The sensitivity of the computed natural frequency and damping to the soil properties was evaluated through parametric studies. About 10-20% of discrepancy in values of natural frequency was observed due to different approaches. The results help to assess the reliability of equivalent soil properties determined from the reported natural frequency of the system. Finally the results obtained using theoretical predictions with linear soil properties measured in situ were compared to those calculated from experimental data. The prediction and experimental results showed good agreements if the embedment of the foundation is neglected with stepped sine test but considered with impulse test. © 2010 Elsevier Ltd.

Unified compression model for venice lagoon natural silts

Over the last 50 years, the city of Venice, Italy, has observed a significant increase in the frequency of flooding. Numerous engineering solutions have been proposed, including the use of movable gates located at the three lagoon inlets. A key element in the prediction of performance is the estimation of settlements of the foundation system of the gates. The soils of Venice Lagoon are characterized by very erratic depositional patterns of clayey silts, resulting in an extremely heterogeneous stratigraphy with discontinuous layering. The soils are also characterized by varying contents of coarse and fine-grained particles. In contrast, the mineralogical composition of these deposits is quite uniform, which allows us to separate the influence of mineralogy from that of grain size distribution. A comprehensive geotechnical testing program was performed to assess the one-dimensional compression of Venice soils and examine the factors affecting the response in the transition from one material type to another. The compressibility of these natural silty clayey soils can be described by a single set of constitutive laws incorporating the relative fraction of granular to cohesive material. © 2007 ASCE.

An expressive text-driven 3D talking head

Creating a realistic talking head, which given an arbitrary text as input generates a realistic looking face speaking the text, has been a long standing research challenge. Talking heads which cannot express emotion have been made to look very realistic by using concatenative approaches [Wang et al. 2011], however allowing the head to express emotion creates a much more challenging problem and model based approaches have shown promise in this area. While 2D talking heads currently look more realistic than their 3D counterparts, they are limited both in the range of poses they can express and in the lighting conditions that they can be rendered under. Previous attempts to produce videorealistic 3D expressive talking heads [Cao et al. 2005] have produced encouraging results but not yet achieved the level of realism of their 2D counterparts.

Centrifuge testing of monopiles subject to cyclic lateral loading

Monopiles supporting offshore wind turbines are subjected to cyclic lateral loading. The properties of the applied cyclic lateral load are known to have an effect on the accumulation of permanent displacement and rotation at the pile head. The results of centrifuge testing on model piles show that certain loading regimes lead to the development of locked in soil stresses around the pile. These locked in soil stresses change the stiffness of the monopile response to cyclic lateral loading and the natural frequency of the pile-soil system. © 2014 Taylor & Francis Group.

Ontogeny of IgM-producing cells in the mandarin fish Siniperca chuatsi identified by in situ hybridisation

The ontogeny of IgM-producing cells was studied in juvenile mandarin fish Simperca chuatsi, an important fish in China's aquaculture sector. The IgM-producing cells were localised through in situ hybridisation with a probe complementary to the Ig mu-chain in lymphoid-related tissues, including head kidney, spleen, thymus, intestine and gills. In head kidney, transcripts of Ig mu were first detected at 20 days post-hatching (dph) with a few positive signals. and the number of IgM-producing cells increased obviously from 39 dph onwards. At 136 dph, a large amount of positive cells were observed in the entire organ with clusters of these cells located around the blood vessels. In spleen, IgM-producing cells were found from 26 dph onwards, followed by an increase until 67 dph: clusters of positive cells were also detected around blood vessels at 102 dph. In thymus, IgM-producing cells were first observed at 39 dph; thereafter, no obvious increase was detected until 78 dph. The positive cells in thymus were distributed mainly in the outer zone of thymus. A few IgM-producing cells were still observed in thymus of 1-year-old mandarin fish. IgM-producing cells were not detected in the intestine until 87 dph, with several discrete positively stained cells distributed in the lamina propria. IgM-producing cells, scattered mainly in primary gill filaments around blood vessels, were detected in gills from 90 dph. As in other teleosts, these results indicated that the head kidney appears to be the primary organ for IgM production in mandarin fish, and IgM-producing cells exist in all organs examined in the present study, implying their lymphoid role in fish. In addition, it is suggested that vaccination after 20 dph may be much more effective in mandarin fish. (C) 2009 Elsevier B.V. All rights reserved.

Onychostoma virgulatum, a new species of cyprinid fish (Pisces: Teleostei) from southern Anhui Province, South China

Onychostoma virgulatum, new species, is described from the Qiupu River, a tributary on the Southern bank of the lower Yangtze River at Shitai County, southern Anhui Province, South China. It shares with O. fusiforme and O. meridionale the presence of a longitudinal dark brown stripe extending along the lateral line, a character separating them from all other congeners of the moderate-mouth group diagnosed by having a slightly arched or nearly transverse mouth opening (with the extremities slightly curved posteriorly), its width being equal to or slightly less than the width of head at this same point, and a short postlabial groove extending along half of the length of the lateral margin of the lower jaw. Onychostoma virgulatum differs from both in the presence of two pairs of barbels in adults, from O. fusiforme in the body depth, caudal-peduncle depth, and position of pelvic and anal fins, and from O. meridionale in the structure of the last simple dorsal-fin ray.

Ultrastructure of the Spermatozoa of the Yangtze Finless Porpoise (Neophocaena phocaenoides asiaeorientalis)

P>Semen sample was collected from two captive adult Yangtze finless porpoises (Neophocaena phocaenoides asiaeorientalis) during physical examination. One individual was aged about 9 years with body length 143 cm (total length) and body weight 46.1 kg in 2003. The age of the other was unknown and its body length was 147 cm and body weight was 43 kg in 2004. Ultrastructure of their spermatozoa was examined using scanning and transmission electron microscope. The sperm concentration was 4.17 x 10(9) spermatozoa per ml by the cytometer. The approximate dimensions of the spermatozoa were as follows: head length, 3.366 +/- 0.140 mu m (mean +/- SE, n = 15); head width, 1.896 +/- 0.099 mu m (n = 15); and neck length, 1.004 +/- 0.074 mu m (n = 10). The tail included midpiece, principal piece and terminal piece. The length of the midpiece was 1.882 +/- 0.077 mu m (n = 9). There is no apparent boundary between the principal piece and the terminal piece, so the length of the principal piece and the terminal piece was 44.612 +/- 3.485 mu m (n = 5). Total length of the spermatozoa was 53.314 +/- 4.580 mu m (n = 10). The acrosome covered approximately 45.8% of the anterior portion of the head.

Effects of cyanobacterial toxin microcystin-LR on the transcription levels of immune-related genes in grass carp Ctenopharyngodon idella

Recent studies in mammals have revealed that the cyanobacterial toxin MC-LR suppresses immune functions. Nevertheless, immunotoxic effects of microcystins have been little studied in fish. In this paper, we present the profiles of the immune modulation of MC-LR in grass carp, and quantitative real-time PCR methodology was developed for the measurement of relative transcription changes of six immune-related genes in the spleen and head kidney of the grass carp Ctenopharyngodon idella, which were intraperitoneally injected with 50 mu g MC-LR center dot kg(-1) body weight in a three-week period. This study was focused exclusively on gene transcription level changes at different time points after MC-LR exposure, so, only one dose was given. The investigated genes were interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), type I interferon (Type I IFN), peptidoglycan recognition protein-L (PGRP-L), immunoglobulin M (IgM) and major histocompatibility complex class I (MHC-I) genes. The results demonstrated that the transcription levels of the TNF-alpha, type I IFN, and PGRP-L genes in the spleen and head kidney were significantly low at all time points, and those of IL-1 beta were significantly low in the head kidney at different time points. In addition, IgM and MHC-I transcription levels were only significantly low in the spleen and head kidney at 21 d postinjection. The changes in the transcription levels of immune-related genes induced by MC-LR confirmed its effect on inhibiting immune function at the transcription level.

Plasma biochemical responses of the planktivorous filter-feeding silver carp (Hypophthalmichthys molitrix) and bighead carp (Aristichthys nobilis) to prolonged toxic cyanobacterial blooms in natural waters

The planktivorous filter-feeding silver carp (Hypophthalmichthys molitrix) and bighead carp (Aristichthys nobilis) are the attractive candidates for bio-control of plankton communities to eliminate odorous populations of cyanobacteria. However, few studies focused on the health of such fishes in natural water body with vigorous toxic blooms. Blood parameters are useful and sensitive for diagnosis of diseases and monitoring of the physiological status of fish exposed to toxicants. To evaluate the impact of toxic cyanobacterial blooms on the planktivorous fish, 12 serum chemistry variables were investigated in silver carp and bighead carp for 9 months, in a large net cage in Meiliang Bay, a hypereutrophic region of Lake Taihu. The results confirmed adverse effects of cyanobacterial blooms on two phytoplanktivorous fish, which mainly characterized with potential toxicogenomic effects and metabolism disorders in liver, and kidney dysfunction. In addition, cholestasis was intensively implied by distinct elevation of all four related biomarkers (ALP, GGT, DBIL, TBIL) in bighead carp. The combination of LDH, AST activities and DBIL, URIC contents for silver carp, and the combination of ALT. ALP activities and TBIL, DBIL. URIC concentrations for bighead carps were found to most strongly indicate toxic effects from cyanobacterial blooms in such fishes by a multivariate discriminant analysis. (C) 2009 Elsevier B.V. All rights reserved.