Affinities of the family Sollasellidae (Porifera, Demospongiae). I. Morphological evidence

Comparison of Sollasella digitata Lendenfeld, 1888, up until the present assigned to its own family Sollasellidae Lendenfeld, 1887 in the order Hadromerida, and Raspailopsis cervicornis Burton, 1959, assigned to Raspailiidae Nardo, 1833 in the order Poecilosclerida, leads to the conclusion that both should be considered congeneric and are best assigned to a single genus Sollasella. This conclusion is based on examination of habit and skeletal characters of the type material of S. digitata and both type and freshly collected material of S. cervicornis. The conclusion is strengthened by the discovery of a new species, Sollasella moretonensis n.sp. collected in North Australia (primarily in the northeastern coast, but also an isolated record from the northwestern Australian coast), which possesses in addition to the characteristic surface pattern and skeletal structure, genuine echinating acanthostyles. The redefined genus Sollasella shares axial / extra-axial arrangement of the skeleton, special surface brushes of oxeas surrounding a single protruding style, and vestigial occurrence of acanthostyles with many Raspailia s.l. Nevertheless, it is retained as a separate genus, on account of its peculiar polygonal arrangement of surface pores. The distribution of the genus is disjunctive including both (southeast, northeast and northwest) Australian and Western Indian Ocean localities, but so far no intermediate records. Based on this morphological evidence, it is proposed – pending publication of corroborating molecular evidence to be presented in a follow-up study – to reassign Sollasella and the family Sollasellidae to the poecilosclerid family Raspailiidae

Simultaneous Morphological and Flow Imaging Enabled by Megahertz Intravascular Doppler Optical Coherence Tomography

We demonstrate three-dimensional intravascular flow imaging compatible with routine clinical image acquisition workflow by means of megahertz (MHz) intravascular Doppler Optical Coherence Tomography (OCT). The OCT system relies on a 1.1 mm diameter motorized imaging catheter and a 1.5 MHz Fourier Domain Mode Locked (FDML) laser. Using a post processing method to compensate the drift of the FDML laser output, we can resolve the Doppler phase shift between two adjoining OCT A-line datasets. By interpretation of the velocity field as measured around the zero phase shift, the flow direction at specific angles can be qualitatively estimated. Imaging experiments were carried out in phantoms, micro channels, and swine coronary artery in vitro at a speed of 600 frames/s. The MHz wavelength sweep rate of the OCT system allows us to directly investigate flow velocity of up to 37.5 cm/s while computationally expensive phase-unwrapping has to be applied to measure such high speed using conventional OCT system. The MHz sweep rate also enables a volumetric Doppler imaging even with a fast pullback at 40 mm/s. We present the first simultaneously recorded 3D morphological images and Doppler flow profiles. Flow pattern estimation and three-dimensional structural reconstruction of entire coronary artery are achieved using a single OCT pullback dataset

Low cost feeding strategies for dual purpose cattle in Venezuela

This simulation study was to evaluate low cost feeding strategies in response to higher cost of commercial concentrates to maintain current milk sales from dual purpose cattle herds in the humid lowlands of western Venezuela. Data were from farm surveys in 1987 and 1988. Baseline net margins from milk and beef per cow per year were $132 and$99 for two farm cases with average dally milk of 10 and 7 kg/cow and grazing mature forage supplemented with commercial concentrate. Alternative diets were 1) improving forage quality by more intensive grazing; 2) replacing commercial concentrate with a mixture of cassava tuber (Manihot esculenta), urea, and molasses and 3) supplementing grazing with a mixture of molasses and urea. Alternatively priced feeding strategies were compared by partial budgeting. Using less mature forage was .always more profitable than mature grass. Feeding molasses and urea with mature forage increased profits at least $64/cow on the high milk yield farm and$44/cow on the low milk yield farm compared with feeding commercial concentrate. The most costly cassava mixture with mature forage increased annual profit over the baseline diet at least $11/ cow on the high milk yield farm and by$22/cow on the low yield farm. Efficient use of existing feed resources may enhance economical livestock production in the humid lowlands of Venezuela

SCIAMACHY Level 1 data: calibration concept and in-flight calibration

The calibration of SCIAMACHY was thoroughly checked since the instrument was launched on-board ENVISAT in February 2002. While SCIAMACHY's functional performance is excellent since launch, a number of technical difficulties have appeared, that required adjustments to the calibration. The problems can be separated into three types: (1) Those caused by the instrument and/or platform environment. Among these are the high water content in the satellite structure and/or MLI layer. This results in the deposition of ice on the detectors in channels 7 and 8 which seriously affects the retrievals in the IR, mostly because of the continuous change of the slit function caused by scattering of the light through the ice layer. Additionally a light leak in channel 7 severely hampers any retrieval from this channel. (2) Problems due to errors in the on-ground calibration and/or data processing affecting for example the radiometric calibration. A new approach based on a mixture of onground and in-flight data is shortly described here. (3) Problems caused by principal limitations of the calibration concept, e.g. the possible appearance of spectral structures after the polarisation correction due to unavoidable errors in the determination of atmospheric polarisation. In this paper we give a complete overview of the calibration and problems that still have to be solved. We will also give an indication of the effect of calibration problems on retrievals where possible. Since the operational processing chain is currently being updated and no newly processed data are available at this point in time, for some calibration issues only a rough estimate of the effect on Level 2 products can be given. However, it is the intention of this paper to serve as a future reference for detailed studies into specific calibration issues

SCIAMACHY Level 1 data: calibration concept and in-flight calibration

The calibration of SCIAMACHY was thoroughly checked since the instrument was launched on-board ENVISAT in February 2002. While SCIAMACHY's functional performance is excellent since launch, a number of technical difficulties have appeared, that required adjustments to the calibration. The problems can be separated into three types: (1) Those caused by the instrument and/or platform environment. Among these are the high water content in the satellite structure and/or MLI layer. This results in the deposition of ice on the detectors in channels 7 and 8 which seriously affects the retrievals in the IR, mostly because of the continuous change of the slit function caused by scattering of the light through the ice layer. Additionally a light leak in channel 7 severely hampers any retrieval from this channel. (2) Problems due to errors in the on-ground calibration and/or data processing affecting for example the radiometric calibration. A new approach based on a mixture of on-ground and in-flight data is shortly described here. (3) Problems caused by principal limitations of the calibration concept, e.g. the possible appearance of spectral structures after the polarisation correction due to unavoidable errors in the determination of atmospheric polarisation. In this paper we give a complete overview of the calibration and problems that still have to be solved. We will also give an indication of the effect of calibration problems on retrievals where possible. Since the operational processing chain is currently being updated and no newly processed data are available at this point in time, for some calibration issues only a rough estimate of the effect on Level 2 products can be given. However, it is the intention of this paper to serve as a future reference for detailed studies into specific calibration issues

Phylogenetic Relationships of the Marine Haplosclerida (Phylum Porifera) Employing Ribosomal (28S rRNA) and Mitochondrial (cox1, nad1) Gene Sequence Data

The systematics of the poriferan Order Haplosclerida (Class Demospongiae) has been under scrutiny for a number of years without resolution. Molecular data suggests that the order needs revision at all taxonomic levels. Here, we provide a comprehensive view of the phylogenetic relationships of the marine Haplosclerida using many species from across the order, and three gene regions. Gene trees generated using 28S rRNA, nad1 and cox1 gene data, under maximum likelihood and Bayesian approaches, are highly congruent and suggest the presence of four clades. Clade A is comprised primarily of species of Haliclona and Callyspongia, and clade B is comprised of H. simulans and H. vansoesti (Family Chalinidae), Amphimedon queenslandica (Family Niphatidae) and Tabulocalyx (Family Phloeodictyidae), Clade C is comprised primarily of members of the Families Petrosiidae and Niphatidae, while Clade D is comprised of Aka species. The polyphletic nature of the suborders, families and genera described in other studies is also found here

Thermo-elastic optical coherence tomography

The absorption of nanosecond laser pulses induces rapid thermo-elastic deformation in tissue. A sub-micrometer scale displacement occurs within a few microseconds after the pulse arrival. In this Letter, we investigate the laser-induced thermo-elastic deformation using a 1.5 MHz phase-sensitive optical coherence tomography (OCT) system. A displacement image can be reconstructed, which enables a new modality of phase-sensitive OCT, called thermo-elastic OCT. An analysis of the results shows that the optical absorption is a dominating factor for the displacement. Thermo-elastic OCT is capable of visualizing inclusions that do not appear on the structural OCT image, providing additional tissue type information