Image registration techniques with multiresolution analysis in satellite oceanography

En aquest article es fa una descripció dels procediments realitzats per enregistrar dues imatges geomètricament, de forma automàtica, si es pren la primera com a imatge de referència. Es comparen els resultats obtinguts mitjançant tres mètodes. El primer mètode és el d’enregistrament clàssic en domini espacial maximitzant la correlació creuada (MCC)[1]. El segon mètode es basa en aplicar l’enregistrament MCC conjuntament amb un anàlisi multiescala a partir de transformades wavelet [2]. El tercer mètode és una variant de l’anterior que es situa a mig camí dels dos. Per cada un dels mètodes s’obté una estimació dels coeficients de la transformació que relaciona les dues imatges. A continuació es transforma per cada cas la segona imatge i es georeferencia respecte la primera. I per acabar es proposen unes mesures quantitatives que permeten discutir i comparar els resultats obtinguts amb cada mètode.

The study of insect blood-feeding behaviour: 2. Recording techniques and the use of flow charts

This paper continues a discussion of approaches and methodologies we have used in our studies of feeding in haematophagous insects. Described are techniques for directly monitoring behaviour: electrical recording of feeding behaviour via resistance changes in the food canal, optical methods for monitoring mouthpart activity, and a computer technique for behavioural event recording. Also described is the use of "flow charts" or "decision diagrams" to model interrelated sequences of behaviours.

Membrane potential dynamics of neocortical projection neurons driving target-specific signals.

Primary sensory cortex discriminates incoming sensory information and generates multiple processing streams toward other cortical areas. However, the underlying cellular mechanisms remain unknown. Here, by making whole-cell recordings in primary somatosensory barrel cortex (S1) of behaving mice, we show that S1 neurons projecting to primary motor cortex (M1) and those projecting to secondary somatosensory cortex (S2) have distinct intrinsic membrane properties and exhibit markedly different membrane potential dynamics during behavior. Passive tactile stimulation evoked faster and larger postsynaptic potentials (PSPs) in M1-projecting neurons, rapidly driving phasic action potential firing, well-suited for stimulus detection. Repetitive active touch evoked strongly depressing PSPs and only transient firing in M1-projecting neurons. In contrast, PSP summation allowed S2-projecting neurons to robustly signal sensory information accumulated during repetitive touch, useful for encoding object features. Thus, target-specific transformation of sensory-evoked synaptic potentials by S1 projection neurons generates functionally distinct output signals for sensorimotor coordination and sensory perception.

Combining classification techniques to define topo-climatic landscapes

Landscape classification tackles issues related to the representation and analysis of continuous and variable ecological data. In this study, a methodology is created in order to define topo-climatic landscapes (TCL) in the north-west of Catalonia (north-east of the Iberian Peninsula). TCLs relate the ecological behaviour of a landscape in terms of topography, physiognomy and climate, which compound the main drivers of an ecosystem. Selected variables are derived from different sources such as remote sensing and climatic atlas. The proposed methodology combines unsupervised interative cluster classification with a supervised fuzzy classification. As a result, 28 TCLs have been found for the study area which may be differentiated in terms of vegetation physiognomy and vegetation altitudinal range type. Furthermore a hierarchy among TCLs is set, enabling the merging of clusters and allowing for changes of scale. Through the topo-climatic landscape map, managers may identify patches with similar environmental conditions and asses at the same time the uncertainty involved.

The regional economic impacts of biofuels: A review of multisectoral modelling techniques and evaluation of applications

The regional economic impact of biofuel production depends upon a number of interrelated factors: the specific biofuels feedstock and production technology employed; the sector’s embeddedness to the rest of the economy, through its demand for local resources; the extent to which new activity is created. These issues can be analysed using multisectoral economic models. Some studies have used (fixed price) Input-Output (IO) and Social Accounting Matrix (SAM) modelling frameworks, whilst a nascent Computable General Equilibrium (CGE) literature has also begun to examine the regional (and national) impact of biofuel development. This paper reviews, compares and evaluates these approaches for modelling the regional economic impacts of biofuels.

The regional economic impacts of biofuels: A review of multisectoral modelling techniques and evaluation of applications

The regional economic impact of biofuel production depends upon a number of interrelated factors: the specific biofuels feedstock and production technology employed; the sector’s embeddedness to the rest of the economy, through its demand for local resources; the extent to which new activity is created. These issues can be analysed using multisectoral economic models. Some studies have used (fixed price) Input-Output (IO) and Social Accounting Matrix (SAM) modelling frameworks, whilst a nascent Computable General Equilibrium (CGE) literature has also begun to examine the regional (and national) impact of biofuel development. This paper reviews, compares and evaluates these approaches for modelling the regional economic impacts of biofuels.

The efficiency of Lutz, Kato-Katz and Baermann-Moraes (adapted) techniques association to the diagnosis of intestinal helmints

The association of Lutz/Kato-Katz and Lutz/Bermann-Moraes (adapted techniques was used to improve better results that ranged from 0.4 to 11 times in the search of eggs of Ascaris lumbricoides, Schistosoma mansoni, Trichiuris trichiura, Taenia sp. and larvae of Strongyloides stercoralis.

Plant tissue culture techniques

Plant cell and tissue culture in a simple fashion refers to techniques which utilize either single plant cells, groups of unorganized cells (callus) or organized tissues or organs put in culture, under controlled sterile conditions.

Metallic renal artery MR imaging stent: artifact-free lumen visualization with projection and standard renal MR angiography.

A cardiac-triggered free-breathing three-dimensional (3D) balanced fast field-echo projection renal magnetic resonance (MR) angiographic sequence was investigated for in-stent lumen visualization of a dedicated metallic renal artery stent. Fourteen prototype stents were deployed in the renal arteries of six pigs (in two pigs, three stents were deployed). Projection renal MR angiography was compared with standard contrast material-enhanced 3D breath-hold MR angiography. Artifact-free in-stent lumen visualization was achieved with both projection MR angiography and contrast-enhanced MR angiography. These promising results warrant further studies for visualization of in-stent restenosis.

Indications et techniques actuelles de reconstruction mammaire après mastectomie [Indications and techniques of reconstruction after mastectomy].

Reconstructive surgery takes an important place in breast cancer treatment. Immediate breast reconstruction is performed during the same operation as mastectomy. It is contraindicated following radiotherapy. Reconstruction performed after mastectomy is called differed breast reconstruction. It is completed 6 months after chemotherapy and 1 year after radiotherapy. Prosthetic breast reconstruction is indicated when tissues are of good qualities and breast are small. Autologous reconstruction is performed in case of radiotherapy or large breast. After breast reconstruction, imperfections can be corrected with autologous fat injection.

Choledocholithiasis: repetitive thick-slab single-shot projection magnetic resonance cholangiopancreaticography versus endoscopic ultrasonography.

This prospective study compares repetitive thick-slab single-shot projection magnetic resonance cholangiopancreatography (MRCP) with endoscopic ultrasonography (EUS) for the detection of choledocholithiasis. Fifty-seven consecutive patients (36 women, mean age 61) referred for suspected choledocholithiasis underwent MRCP, followed by EUS. Each procedure was performed by different operators blinded to the results of the other investigation. MR technique included a turbo spin-echo T2-weighted axial sequence with selective fat saturation (SPIR/TSE, TE=70 ms, TR=1,600 ms), followed by coronal dynamic MRCP. The same thick-slab slice was sequentially acquired 12 times as breath-hold single-shot projection imaging (SSh, TE=900 ms, TE=8,000 ms) centred on the common bile duct (CBD). Two experienced radiologists independently and blindly evaluated MR images for the detection of CBD stones. Their inter-observer agreement kappa was determined. Secondly, the two observers read MR images in consensus again. CBD stones were demonstrated in 18 out of 57 patients (31.6 %) and confirmed by endoscopic retrograde cholangiography (ERCP, n=17) or intraoperative cholangiography (n=1). Clinical follow-up served as the "gold standard" in patients with negative results without following invasive procedure (n=28). Sensitivity, specificity, accuracy, positive and negative predictive value for MRCP resulting from consensus reading were 94.9%, 94.4%, 94.7%, 97.4% and 89.5%, respectively. Corresponding values of EUS were 97.4%, 94.4%, 96.5%, 97.4% and 94.4%. Inter-observer agreement kappa was 0.81. Repetitive thick-slab single-shot projection MRCP is an accurate non-invasive imaging modality for suspected choledocholithiasis and should be increasingly used to select those patients who require a subsequent therapeutic procedure, namely ERCP.

Techniques for analytical testing of unconventional samples.

Forensic scientists have long detected the presence of drugs and their metabolites in biological materials using body fluids such as urine, blood and/or other biological liquids or tissues. For doping analysis, only urine has so far been collected. In recent years, remarkable advances in sensitive analytical techniques have encouraged the analysis of drugs in unconventional biological samples such as hair, saliva and sweat. These samples are easily collected, although drug levels are often lower than the corresponding levels in urine or blood. This chapter reviews recent studies in the detection of doping agents in hair, saliva and sweat. Sampling, analytical procedures and interpretation of the results are discussed in comparison with those obtained from urine and blood samples.