Normal Situation (normal + situation)

Distribution by Scientific Domains


Selected Abstracts


SMIXTURE: strategy for mixture model clustering of multivariate images

JOURNAL OF CHEMOMETRICS, Issue 11-12 2005
Thanh N. Tran
Abstract SMIXTURE, a novel strategy for mixture model clustering of multivariate images, has been developed. Most other clustering approaches require good guesses of the number of components (clusters) and the initial statistical parameters. In our approach, the initial parameters are determined by agglomerative clustering on homogenous regions, identified by region growing segmentation. SMIXTURE can be used in both a normal situation of mixture modeling, where the density of a cluster is modeled by a single normal distribution; and in a more complex situation, where the density of a single cluster is a mixture of several normal sub-clusters. The method has proven to be very robust to noise/outliers, overlapping clusters, is reasonably fast and is suitable for moderate to large images. Copyright © 2006 John Wiley & Sons, Ltd. [source]


Reproductive ecology of the reef manta ray Manta alfredi in southern Mozambique

JOURNAL OF FISH BIOLOGY, Issue 1 2010
A. D. Marshall
The application of a photographic identification methodology using the unique ventral surface markings (natural spot patterns) of an observed population in southern Mozambique enabled many aspects of the reproductive ecology of reef manta rays Manta alfredi to be examined. The region encompassing the study site was identified as a mating ground for M. alfredi based on observations of mating events and fresh mating scars on females. The distribution of these pectoral fin scars was highly biased and indicated a strong lateralized behavioural trait, with 99% of these scars occurring only on the left pectoral fin. No other elasmobranch has been reported to display behavioural lateralization. The study region also acts as a birthing ground, with individuals typically giving birth in the austral summer period after a gestation of c. 1 year. Reproductive periodicity in M. alfredi was most commonly biennial, but a few individuals were pregnant in consecutive years, confirming an annual ovulatory cycle. The production of a single pup appears to be the normal situation, although observations in the wild as well as during opportunistic dissections of individuals killed by fisheries revealed that two pups are conceived on occasion. Many aspects of the study have contributed to the limited baseline data currently available for this species and have highlighted the potential need for more conservative conservation strategies. [source]


Remyelination can be extensive in multiple sclerosis despite a long disease course

NEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 3 2007
R. Patani
Experimental studies using models of multiple sclerosis (MS) indicate that rapid and extensive remyelination of inflammatory demyelinated lesions is not only possible, but is the normal situation. The presence of completely remyelinated MS lesions has been noted in numerous studies and routine limited sampling of post mortem MS material suggests that remyelination may be extensive in the early stages but eventually fails. However, visual macroscopic guided sampling tends to be biased towards chronic demyelinated lesions. Here we have extensively sampled cerebral tissue from two MS cases to investigate the true extent of remyelination. Sections were cut from 185 cerebral tissue blocks and stained with haematoxylin and eosin (H&E), luxol fast blue and cresyl fast violet (LFB/CFV) and anti-myelin oligodendrocyte glycoprotein, human leucocyte antigen-DR (HLA-DR) and 200 kDa neurofilament protein antibodies. Demyelinated areas were identified in 141 blocks, comprising both white matter (WMLs) and/or grey matter lesions. In total, 168 WMLs were identified, 22% of which were shadow plaques, 73% were partially remyelinated and only 5% were completely demyelinated. The average extent of lesion remyelination for all WMLs investigated was 47%. Increased density of HLA-DR+ macrophages and microglia at the lesion border correlated significantly with more extensive remyelination. Results from this study of two patients with long standing disease suggest that remyelination in MS may be more extensive than previously thought. [source]


Frequency and nocturia after successful renal transplantation: a normal situation?

BJU INTERNATIONAL, Issue 3 2006
DIRK-HENRIK ZERMANN
OBJECTIVE To analyse lower urinary tract function before and after successful renal transplantation and compare the data with those from a healthy control group. PATIENTS AND METHODS Data were gathered by retrospective analysis of 331 charts of patients transplanted between March 1998 and May 2003, using written questionnaires and personal interview, and investigation of 150 patients. The control group consisted of 150 urologically healthy volunteers. RESULTS Frequency and nocturia were the main lower urinary tract symptoms. Frequency of more than six voids/day was reported by 87% and nocturia of more then one void/night by 93% of all patients after successful renal transplantation. There was no significant correlation with fluid intake, diuretic medication, gender or age. Over the years the number of voids tended to decrease but remained higher than in the control group. However, 94% of all patients were happy with the quality of life after renal transplantation. CONCLUSION Frequency and nocturia are the two main characteristics of lower urinary tract function after renal transplantation, probably through a combination of high fluid intake, a long-term defunctionalized urinary bladder during renal replacement therapy, a denervated donor kidney, concomitant diseases and psychosocial distress. Quality of and satisfaction with life were not compromised. [source]