A diver-operated hyperspectral imaging and topographic surveying system for automated mapping of benthic habitats.

We developed a novel integrated technology for diver-operated surveying of shallow marine ecosystems. The HyperDiver system captures rich multifaceted data in each transect: hyperspectral and color imagery, topographic profiles, incident irradiance and water chemistry at a rate of 15-30 m2 per minute. From surveys in a coral reef following standard diver protocols, we show how the rich optical detail can be leveraged to generate photopigment abundance and benthic composition maps. We applied machine learning techniques, with a minor annotation effort (<2% of pixels), to automatically generate cm-scale benthic habitat maps of high taxonomic resolution and accuracy (93-97%). The ability to efficiently map benthic composition, photopigment densities and rugosity at reef scales is a compelling contribution to modernize reef monitoring. Seafloor-level hyperspectral images can be used for automated mapping, avoiding operator bias in the analysis and deliver the degree of detail necessary for standardized environmental monitoring. The technique can deliver fast, objective and economic reef survey results, making it a valuable tool for coastal managers and reef ecologists. Underwater hyperspectral surveying shares the vantage point of the high spatial and taxonomic resolution restricted to field surveys, with analytical techniques of remote sensing and provides targeted validation for aerial monitoring.

Dobzhansky and Montagu's Debate on Race: The Aftermath.

Dobzhansky and Montagu debated the use and validity of the term "race" over a period of decades. They failed to reach an agreement, and the "debate" has continued to the present. The ms contains an account of the debate to the present. This essay is part of a Special Issue, Revisiting Garland Allen's Views on the History of the Life Sciences in the Twentieth Century.

The alpha2 adrenoreceptor agonist clonidine suppresses evoked and spontaneous seizures, whereas the alpha2 adrenoreceptor antagonist idazoxan promotes seizures in amygdala-kindled kittens.

Microinfusion of alpha2 adrenoreceptor agonists and antagonists into amygdala has contrasting effects on evoked and spontaneous seizure susceptibility in amygdala-kindled kittens. Subjects were 14 preadolescent kittens between 3 and 4 months old at the beginning of kindling. The same protocol was followed except that half the kittens received microinfusions (1 mul) of the alpha2 agonist clonidine (CLON; 1.32 nmol), and half received the alpha2 antagonist idazoxan (IDA; 0.33 nmol). Infusions were made over 1 min through needles inserted into cannulae adjacent to stimulating electrodes in the kindled amygdala, and evoked seizures were tested 10-12 min later. The results were: (1) CLON elevated seizure thresholds obtained once at the beginning and end of kindling, but only when compared to sham control values (needle insertion only) in the same animals; IDA significantly reduced thresholds. (2) CLON retarded and IDA accelerated kindling rate, defined as the number of afterdischarges (ADs) required to achieve the first stage 6 seizure or generalized tonic-clonic convulsion (GTC). These effects were most pronounced on the emergence of seizure "generalization" stages (3-6) from "focal" seizure stages (1-2). (3) CLON prevented onset of spontaneous seizures, whereas IDA precipitated onset of spontaneous seizures in 100% of the animals before or during the 5-week post-kindling follow-up during which seizures were evoked once each work day. The study confirms previous findings in kindled rodents to show that CLON and IDA can have opposing effects on kindling development in kittens and is the first report to show contrasting effects on spontaneous epileptogenesis in kindled animals as well.

Ontogeny of feline temporal lobe epilepsy in amygdala-kindled kittens: an update.

This report describes amygdala-kindled seizure development and the post-kindling course in 58 cats (29 males and 29 females), including 40 preadolescents between 2.5 and 6.5 months of age and 18 adults >1 year of age at the beginning of kindling. The results extend previous findings, as follows: (1) Youngest animals (<5.0 months, n=30) are far more likely than older kittens and adults to exhibit spontaneous epilepsy, indexed by seizures that occur >1 h after stimulus-evoked seizures. (2) The youngest animals also exhibit accelerated kindling rates and rapid post-kindling onset of multifocal spontaneous epilepsy with a catastrophic clinical course. The profile includes a variety of EEG and/or clinical seizure manifestations and a progressive increase in the number and density of convulsive seizure clusters. Behavioral sequelae accompany seizure clusters and can range from sensory or motor deficits (visual agnosia, sensory hypersensitivity, atonic episodes, restricted mobility) to social isolation and placidity. (3) Onset of spontaneous epilepsy with developmental deterioration is substantially enhanced by recurrent evoked seizures early in the post-kindling course. The post-kindling progression can be stopped or minimized by suspension of evoked seizure trials and/or by management of frequent spontaneous convulsions (>1 per hour) with anticonvulsants. (4) In older cats, many more evoked seizures are required to generate fewer spontaneous seizures with relatively innocuous behavioral disorders. The findings suggest a 'critical period' in kindled kittens for onset of spontaneous temporal lobe epilepsy with severe behavioral consequences and a favorable prognosis for the young following early detection and intervention.

Development of a Real Time PCR system for detection of Penicillium nordicum and for monitoring ochratoxin A production in foods by targeting the ochratoxin polyketide synthase gene.

A 750 bp DNA fragment from the genome of Penicillium nordicum was isolated using degenerated primers for polyketide synthase genes. All analyzed P. nordicum strains possessed the fragment, whereas the closely related ochratoxinogenic P. verrucosum strains did not. The nucleotide sequence of the fragment has been determined. It shows homology to the pksL2 polyketide synthase gene from A. parasiticus. The deduced amino acid sequence of this fragment shows high homology to several other fungal polyketide synthases. An expression analysis of this gene by Reverse Transcription Real Time PCR demonstrates that this putative polyketide synthase gene (otapksPN) is highly induced under ochratoxin A producing conditions, but only to low levels under non-producing conditions. A Real Time PCR system based on the otapksPN sequence has been used to monitor growth and ochratoxin A production of P. nordicum in wheat. A strong correlation between the copy numbers of the otapksPN gene and the colony forming units (cfu) has been observed. In addition there was a strong congruence between otapksPN gene expression and ochratoxin A production in wheat. According to these results the fragment is obviously part of a polyketide synthase (otapksPN) which seems to be involved in the production of ochratoxin A.

Race-mixing and science in the United States.

Scientific racism was widely used as a justification to oppose race-mixing in the United States. Historians have justly criticized this abuse of science, but have overlooked some of the important ways in which science was used in the 1930s and 1940s to overturn scientific racism and opposition to race-mixing. Of particular importance was the cultural anthropology of Franz Boas and the evolutionary biology of Theodosius Dobzhansky, which supplied arguments against racism and fundamentally altered the scientific understanding of race.

Monitoring the production of aflatoxin B1 in wheat by measuring the concentration of nor-1 mRNA.

A real-time reverse transcription-PCR system has been used to monitor the expression of an aflatoxin biosynthetic gene of Aspergillus flavus in wheat. Therefore, total RNA was isolated from infected wheat samples, reverse transcribed and subjected to real-time PCR. In parallel all samples were analyzed by high-pressure liquid chromatography for aflatoxin B(1) production. The primer-probe system of the real-time PCR was targeted against nor-1, a gene of the aflatoxin biosynthetic pathway. By application of this method the nor-1 transcription was quantified during the course of incubation. After 4 days of incubation nor-1 mRNA could be detected for the first time. The amount of nor-1 mRNA increased rapidly, and the maximum was achieved after 6 days. Then, starting very slowly, the mRNA was degraded until day 8, and this was followed by a very fast degradation, reaching nondetectable levels at days 9 and 10. First traces of aflatoxin B(1)could be detected between the 5th and 6th day of incubation. The aflatoxin concentration reached its maximum after 9 days of incubation and remained constant for the whole period of observation. To ensure that differences in the nor-1 mRNA concentration were due to different expression levels, the expression of the constitutively expressed beta-tubulin gene (benA56) has also been monitored. The expression of benA56 remained constant during the whole incubation time. As a parameter for fungal growth, the number of nor-1 gene copies was determined during the course of incubation. The numbers of nor-1 gene copies increased at the beginning of the incubation and reached a plateau at day 5. They correlate well with the viable counts albeit at a higher level.

Quantification of the copy number of nor-1, a gene of the aflatoxin biosynthetic pathway by real-time PCR, and its correlation to the cfu of Aspergillus flavus in foods.

A real-time PCR system directed against the nor-1 gene of the aflatoxin biosynthetic pathway as a target sequence has been applied to detect an aflatoxinogenic A. flavus strain in plant-type foods like maize, pepper and paprika. The system is based on the TaqMan fluorescent probe technology. The copy numbers of the nor-1 gene were compared to conventional cfu data obtained from the same set of samples. In general, a good correlation between nor-1 gene copy number and the cfu data was observed; however, the nor-1 copy numbers were always higher. It was shown that the system is specific for nor-1 containing species.

Molecular characterization of ochratoxin A producing strains of the genus Penicillium.

Sixty-six strains classified as P. verrucosum based on morphological criteria were characterized by molecular methods like RAPD, AFLP and ITS sequencing. Two groups could be identified by RAPD and AFLP analyses. The two RAPD as well as the two AFLP groups were completely coincidental. Strains in the two groups differed in their ability to produce ochratoxin A, with group I containing mainly high producing strains, and group II containing moderate to non-producing strains. The strains from group I originate from foods, such as cheeses and meat products, while the strains from group II originate from plants. The ribosomal ITS1-5.8S-ITS2 sequences were similar, except for two single nucleotide exchanges in several strains of each group. A chemotaxonomical analysis of some of the strains identified differences between the groups in secondary metabolite production. Strains from group I possessed the chemotype of P. nordicum and strains from group II that of P. verrucosum. The differences at the RAPD and AFLP level, which parallel the chemotypic differences, are consistent with the recent reclassification of ochratoxin A producing penicillia to be either P. verrucosum or P. nordicum. The homolgy between the ITS sequences however indicates phylogenetic relationship between the two species.

Molecular characterization of ochratoxin A producing penicillia.

Sixty-six strains classified as P. verrucosum based on morphological criteria were characterized by RAPD analysis. Two groups could be identified which differed in their ability to produce ochratoxin A (OTA). Group I originating from proteinacious foods containing mainly high OTA producing strains, and group II originating from plants containing moderate to non-producing strains. The differences at the RAPD level are consistent with the recent reclassification of ochratoxin A producing penicillia to be either P. verrucosum or P. nordicum.