Fast Transforms for Acoustic Imaging-Part I: Theory

The classical approach for acoustic imaging consists of beamforming, and produces the source distribution of interest convolved with the array point spread function. This convolution smears the image of interest, significantly reducing its effective resolution. Deconvolution methods have been proposed to enhance acoustic images and have produced significant improvements. Other proposals involve covariance fitting techniques, which avoid deconvolution altogether. However, in their traditional presentation, these enhanced reconstruction methods have very high computational costs, mostly because they have no means of efficiently transforming back and forth between a hypothetical image and the measured data. In this paper, we propose the Kronecker Array Transform ( KAT), a fast separable transform for array imaging applications. Under the assumption of a separable array, it enables the acceleration of imaging techniques by several orders of magnitude with respect to the fastest previously available methods, and enables the use of state-of-the-art regularized least-squares solvers. Using the KAT, one can reconstruct images with higher resolutions than was previously possible and use more accurate reconstruction techniques, opening new and exciting possibilities for acoustic imaging.

A Model for comparing reduced impact logging with conventional logging for an Eastern Amazonian Forest

Using data from a logging experiment in the eastern Brazilian Amazon region, we develop a matrix growth and yield model that captures the dynamic effects of harvest system choice on forest structure and composition. Multinomial logistic regression is used to estimate the growth transition parameters for a 10-year time step, while a Poisson regression model is used to estimate recruitment parameters. The model is designed to be easily integrated with an economic model of decisionmaking to perform tropical forest policy analysis. The model is used to compare the long-run structure and composition of a stand arising from the choice of implementing either conventional logging techniques or more carefully planned and executed reduced-impact logging (RIL) techniques, contrasted against a baseline projection of an unlogged forest. Results from log and leave scenarios show that a stand logged according to Brazilian management requirements will require well over 120 years to recover its initial commercial volume, regardless of logging technique employed. Implementing RIL, however, accelerates this recovery. Scenarios imposing a 40-year cutting cycle raise the possibility of sustainable harvest volumes, although at significantly lower levels than is implied by current regulations. Meeting current Brazilian forest policy goals may require an increase in the planned total area of permanent production forest or the widespread adoption of silvicultural practices that increase stand recovery and volume accumulation rates after RIL harvests. Published by Elsevier B.V.

Nitrogen fertilization in common bean crops under no-tillage and conventional systems.

Nitrogen fertilization in common bean crops under no-tillage and conventional systems. Nitrogen fertilizer is necessary for high yields in common bean crops and N responses under conditions of no-tillage and conventional systems are still basic needs. Thus, the objective of this research was to evaluate the effect of N application and common bean yield in no-tillage and conventional systems. The experimental design was a randomized block in a factorial scheme (2x8+1) with four replications. The treatments were constituted by the combination of two N doses (40 and 80 kg ha(-1)) applied at side dressing at eight distinct stadia during vegetative development of the common bean (V(4-3), V(4-4), V(4-5), V(4-6), V(4-7), V(4-8), V(4-9) and V(4-10)), in addition to a control plot without N in side dressing. The experiment was conducted over two years (2002 and 2003) in no-tillage on millet crop residues and conventional plow system. It was concluded that N fertilizer at the V(4) stadium of common bean promotes similar seed yields in no-tillage and conventional systems. Yield differences between no-tillage and conventional systems are inconsistent in the same agricultural area.

Interference of raw milk autochthonous microbiota on the performance of conventional methodologies for Listeria monocytogenes and Salmonella spp. detection

Pathogen detection in foods by reliable methodologies is very important to guarantee microbilogical safety. However, peculiar characteristics of certain foods, such as autochthonous microbiota, can directly influence pathogen development and detection. With the objective of verifying the performance of the official analytical methodologies for the isolation of Listeria monocytogenes and Salmonella in milk, different concentrations of these pathogens were inoculated in raw milk treatments with different levels of mesophilic aerobes, and then submitted to the traditional isolation procedures for the inoculated pathogens. Listeria monocytogenes was inoculated at the range of 0.2-5.2 log CFU/mL in treatments with 1.8-8.2 log CFU/mL. Salmonella Enteritidis was inoculated at 0.9-3.9 log CFU/mL in treatments with 3.0-8.2 log CFU/mL. The results indicated that recovery was not possible or was more difficult in the treatments with high counts of mesophilic aerobes and low levels of the pathogens, indicating interference of raw milk autochthonous microbiota. This interference was more evident for L. monocytogenes, once the pathogen recovery was not possible in treatments with mesophilic aerobes up to 4.0 log CFU/mL and inoculum under 2.0 log CFU/mL. For S. Enteritidis the interference appeared to be more non-specific. (C) 2007 Elsevier GmbH. All rights reserved.

Bioequivalence assay between orally disintegrating and conventional tablet formulations in healthy volunteers

The purpose of this study was to evaluate bioequivalence of two commercial 8 mg tablet formulations of ondansetrona available ill the Brazilian market. In this study, a simple, rapid, sensitive and selective liquid chromarography-tandem mass spectrometry method is described for the determination of ondansetron in human plasma samples. The method was validated over a concentration range of 2.5-60 ng/ml and used in a bioequivalence trial between orally disintegrating and conventional tablet ondansetron formulations, to assess its usefulness in this kind of Study. Vonau flash (R) (Biolab Sanus Farmaceutica, Brazil, as test formulations) and Zofran (R) (GlaxoSmithKline, Brazil, as reference formulation) were evaluated following a single 8 mg close to 23 healthy volunteers of both genders. The dose was administered after an overnight fast according to a two-way crossover design. Bioequivalence between the products was determinated by Calculating 90% confidence interval (90% CI) for the ratio of C(max), AUC(0-t) and AUC(0-(sic)) values for the test and reference products, using logarithmically transformed data. The 90% confidence interval for the ratio of C(max) (87.5-103.8%), AUC(0-t) (89.3-107.2%) and AUC(0--(sic)) (89.7-106.0%) values for the test and reference products is Within the 80-125% interval, proposed by FDA, EMEA and ANVISA. It was concluded that two ondansetron formulations are bioequivalent ill their rate and extent of absorption. (C) 2008 Elsevier B.V. All rights reserved.

Defining a role for the subthalamic nucleus within operative theoretical models of subcortical participation in language

Objective:To investigate the effects of bilateral, surgically induced functional inhibition of the subthalamic nucleus (STN) on general language, high level linguistic abilities, and semantic processing skills in a group of patients with Parkinson’s disease. Methods:Comprehensive linguistic profiles were obtained up to one month before and three months after bilateral implantation of electrodes in the STN during active deep brain stimulation (DBS) in five subjects with Parkinson’s disease (mean age, 63.2 years). Equivalent linguistic profiles were generated over a three month period for a non-surgical control cohort of 16 subjects with Parkinson’s disease (NSPD) (mean age, 64.4 years). Education and disease duration were similar in the two groups. Initial assessment and three month follow up performance profiles were compared within subjects by paired t tests. Reliability change indices (RCI), representing clinically significant alterations in performance over time, were calculated for each of the assessment scores achieved by the five STN-DBS cases and the 16 NSPD controls, relative to performance variability within a group of 16 non-neurologically impaired adults (mean age, 61.9 years). Proportions of reliable change were then compared between the STN-DBS and NSPD groups. Results:Paired comparisons within the STN-DBS group showed prolonged postoperative semantic processing reaction times for a range of word types coded for meanings and meaning relatedness. Case by case analyses of reliable change across language assessments and groups revealed differences in proportions of change over time within the STN-DBS and NSPD groups in the domains of high level linguistics and semantic processing. Specifically, when compared with the NSPD group, the STN-DBS group showed a proportionally significant (p

Adult language input in the early childhood educational setting

Age-related changes in the adult language addressed to children aged 2;0-4;0 years in polyadic conditions were investigated in Australian childcare centres. The language that 21 staff members addressed to these children was coded for multiple variables in the broad social categories of prosody, context, speech act and gesture. The linguistic components were coded within the categories of phonology, lexicon, morphology, syntax and referential deixis. Minimal age-related differences were found. Explanations for the similarity of the adult language input across the age groups within the early childhood educational environment, will be discussed

The Equilibrium Flux Method for the calculation of flows with non-equilbrium chemical reactions

The Equilibrium Flux Method [1] is a kinetic theory based finite volume method for calculating the flow of a compressible ideal gas. It is shown here that, in effect, the method solves the Euler equations with added pseudo-dissipative terms and that it is a natural upwinding scheme. The method can be easily modified so that the flow of a chemically reacting gas mixture can be calculated. Results from the method for a one-dimensional non-equilibrium reacting flow are shown to agree well with a conventional continuum solution. Results are also presented for the calculation of a plane two-dimensional flow, at hypersonic speed, of a dissociating gas around a blunt-nosed body.

Hemispheric contributions to lexical ambiguity resolution: Evidence from individuals with complex language impairment following left-hemisphere lesions

Nine individuals with complex language deficits following left-hemisphere cortical lesions and a matched control group (n 5 9) performed speeded lexical decisions on the third word of auditory word triplets containing a lexical ambiguity. The critical conditions were concordant (e.g., coin–bank–money), discordant (e.g., river–bank–money), neutral (e.g., day–bank– money), and unrelated (e.g., river–day–money). Triplets were presented with an interstimulus interval (ISI) of 100 and 1250 ms. Overall, the left-hemisphere-damaged subjects appeared able to exhaustively access meanings for lexical ambiguities rapidly, but were unable to reduce the level of activation for contextually inappropriate meanings at both short and long ISIs, unlike control subjects. These findings are consistent with a disruption of the proposed role of the left hemisphere in selecting and suppressing meanings via contextual integration and a sparing of the right-hemisphere mechanisms responsible for maintaining alternative meanings.

Language disorders in dementia of the Alzheimer type

The language profile of a group of 18 Alzheimer patients is documented and their performance on a standard aphasia test battery compared to a group of institutionalized, nonneurologically impaired control subjects matched for age, sex, and educational level. The Alzheimer patients scored significantly lower than the controls in the areas of verbal expression, auditory comprehension, repetition, reading, and writing. Articulation abilities were the same in each group. A language deficit was evident in all Alzheimer patients. The language disorder exhibited resembled a transcortical sensory aphasia. Syntax and phonology remained relatively intact but semantic abilities were impaired. The results support the inclusion of a language deficit as a diagnostic criterion of Alzheimer's disease.

Modal functions of future tenses in French

The paper disputes two influential claims in the Romance Linguistics literature. The first is that the synthetic future tenses in spoken Western Romance are now rivalled, if not supplanted, as temporal functors by the more recently developed GO futures. The second is that these synthetic futures now have modal rather than temporal meanings in spoken Romance. These claims are seen as reflecting a universal cycle of diachronic change, in which verb forms originally expressing modal (or aspectual) values take on future temporal reference, becoming tenses. The new modal meanings supplant the temporal, which are then taken up by new forms. Challenges to this theory for French are raised on the basis of empirical evidence of two sorts. Positively, future tenses in spoken Romance continue to be used with temporal meaning. Negatively, evidence of modal meaning for these forms is lacking. The evidence comes froma corpora of spoken French, native speaker judgements and verb data from a daily broadsheet. Cumulatively, it points to the reverse of the claims noted above: the synthetic future in spoken French has temporal but little modal meaning.

One size doesn't fit all: Research methodologies in a language variation study of Sudanese teens

The research reported here draws on a study of five teenagers from a Dinka-speaking community of Sudanese settling in Australia. A range of factors including language proficiency, social network structure and language attitudes are examined as possible causes for the variability of language use. The results and discussion illustrate how the use of a triangular research approach captured the complexity of the participants' language situation and was critical to developing a full understanding of the interplay of factors influencing the teens' language maintenance and shift in a way that no single method could. Further, it shows that employment of different methodologies allowed for flexibility in data collection to ensure the fullest response from participants. Overall, this research suggests that for studies of non-standard communities, variability in research methods may prove more of a strength that the use of standardised instruments and approaches.