Diffraction-limited CCD imaging with faint reference stars

By selecting short exposure images taken using a CCD with negligible readout noise we obtained essentially diffraction-limited 810 nm images of faint objects using nearby reference stars brighter than I=16 at a 2.56 m telescope. The FWHM of the isoplanatic patch for the technique is found to be 50 arcseconds, providing ~20% sky coverage around suitable reference stars.Comment: 4 page letter accepted for publication in Astronomy and Astrophysic

Fat herniation through the canal of Schwalbe

The authors report a case of fat herniation through the canal of Schwalbe noted in a female cadaver during abdominopelvic dissection. Perineal hernias are rare hernias, and herniations through the hiatus of Schwalbe represent a rare posterior lateral perineal hernia. While these hernias are extremely rare, anatomists and surgeons should be aware of them, and the clinical significance and manifestations which may occur with these hernias

ESPRI data-reduction strategy and error budget for PRIMA

The Exoplanet Search with PRIma (ESPRI) will use the PRIMA dual-feed astrometric capability on the Very Large Telescope Interferometer (VLTI) to perform astrometric detections of extra-solar planets. We present an overview of our data-reduction strategy for achieving 10-μarcsecond accuracy narrow-angle astrometry using the PRIMA instrument. We discuss the error budget for astrometric measurements, and those aspects of our strategy which are designed to minimise the astrometric measurement error

Abnormal branching of the axillary artery: an axillo-hepatic artery

The axillary artery is a continuation of the subclavian at the outer border of first rib. Reports of anatomic variations of the axillary artery encountered during cadaveric dissection are not uncommon. However, abnormal branching patterns of the axillary artery identified on imaging studies are rare. We encountered an abnormal branch of the right axillary artery, which descended along the lateral thoraco-abdominal wall and gave off branches to the liver capsule before terminating at the level of the ipsilateral iliac crest. Knowledge of this variation, which we term the axillo-hepatic artery, will be of interest to anatomists, radiologists and adult- and pediatric- surgeons operating on the upper chest and abdominal regions. To our knowledge, such a vessel has not been reported previously in the extant medical literature

Morphologic variation of the diaphragmatic crura: a correlation with pathologic processes of the esophageal hiatus?

The contributions of muscle fibers from the right and left diaphragmatic crura to the formation of the esophageal hiatus have been documented in several studies, none coming to a complete consensus on the number of anatomic variations or the prevalence of these variations in the human population. These variations may play a role in the pathogenicity of specific diseases that involve the esophageal hiatus, such as hiatal hernias. We examined a total of two hundred adult cadavers during 2000-2007. The variations in the diaphragmatic crura, particularly their muscular contributions to the formation of the esophageal hiatus, were grossly examined and revealed a bilateral occurrence of diaphragmatic crura in all 200 specimens. The results of the various morphological patterns of circumferential muscle fibers forming the esophageal hiatus were classified into six groups. The most common type (Type I, 45%) formed the esophageal hiatus from muscular contributions arising solely from the right crus. In Type II (20%) the esophageal hiatus was formed by muscular contributions from the right and left crura. In Type III (15%), the right and left muscular contributions arose from the right crus with an additional band from the left crus. Type IV (10%) showed that the right and left muscular contributions arose from the right crus, with two additional (anterior and posterior) bands arising from the left crus. Type V (5%) demonstrated the contributions arising solely from the left crus. In Type VI (5%) the right and left contributions originated from the left crus with two additional bands, one from the right crus and one from the left crus. These variations may play a role in the pathogenicity of specific diseases that involve the esophageal hiatus such as hiatal hernia, gastroesophageal reflux disease and Dunbar’s syndrome

The astrometric data reduction software (ADRS) and error budget for PRIMA

The Astrometric Data-Reduction Software (ADRS) processes fringe, delay, environmental, and calibration data for PRIMA narrow-angle astrometry. It is automated software designed to provide fully-calibrated differential delays and separation angles. The ADRS is divided into on-line and off-line processing. The former deals with calibration and data compression, while the latter applies corrections and calculates science quantities. PRIMA is the first VLTI instrument that may require removal of long-term environmental trends. The trend identification and fitting routines are not part of the distributed on-line and off-line processing software. Instead, files containing fit parameters will be updated regularly. Coding is presently underway. The PRIMA error budget summarizes the principal sources of error in PRIMA astrometric observation

The effect of green algal mats on intertidal macrobenthic communities and their predators

Eutrophication by sewage effluent has led to the development of extensive mats of green algae over much of the former open mudlands of Langstone Harbour on the south coast of Britain. The presence of the mal reduces the biomass and diversity of the mud-dwelling infauna but a great increase in the number and biomass of epibenthic animals (primarily Hydrobia ulvae Pennant) produces a total biomass almost twice that of open mudlands. Although the common invertebrates are favoured prey for many estuarine birds these algal areas are avoided by the dense aggregation of waders and wildfowl

Microsurgical Anatomy of the Superior Wall of the Mandibular Canal and Surrounding Structures: Suggestion for New Classifications for Dental Implantology

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154467/1/ca23456_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154467/2/ca23456.pd

The ESPRI project: narrow-angle astrometry with VLTI-PRIMA

We describe the ongoing hardware and software developments that shall enable the ESO VLTI to perform narrow-angle differential delay astrometry in K-band with an accuracy of up to 10 μarcsec. The ultimate goal of these efforts is to perform an astrometric search for extrasolar planets around nearby star