Integrated Monitoring of Mola mola Behaviour in Space and Time.

Over the last decade, ocean sunfish movements have been monitored worldwide using various satellite tracking methods. This study reports the near-real time monitoring of fine-scale (< 10 m) behaviour of sunfish. The study was conducted in southern Portugal in May 2014 and involved satellite tags and underwater and surface robotic vehicles to measure both the movements and the contextual environment of the fish. A total of four individuals were tracked using custom-made GPS satellite tags providing geolocation estimates of fine-scale resolution. These accurate positions further informed sunfish areas of restricted search (ARS), which were directly correlated to steep thermal frontal zones. Simultaneously, and for two different occasions, an Autonomous Underwater Vehicle (AUV) video-recorded the path of the tracked fish and detected buoyant particles in the water column. Importantly, the densities of these particles were also directly correlated to steep thermal gradients. Thus, both sunfish foraging behaviour (ARS) and possibly prey densities, were found to be influenced by analogous environmental conditions. In addition, the dynamic structure of the water transited by the tracked individuals was described by a Lagrangian modelling approach. The model informed the distribution of zooplankton in the region, both horizontally and in the water column, and the resultant simulated densities positively correlated with sunfish ARS behaviour estimator (rs = 0.184, p<0.001). The model also revealed that tracked fish opportunistically displace with respect to subsurface current flow. Thus, we show how physical forcing and current structure provide a rationale for a predator's fine-scale behaviour observed over a two weeks in May 2014.

Unusual presentation of a Meckel's diverticulum: A case report.

INTRODUCTION: Meckel's diverticulum (MD) is the most common congenital malformation of the gastrointestinal tract. Intestinal obstruction is the lead presenting symptom in the adult population due to multiple causes (intussusception, incarceration, adhesions, strictures and torsion). Our patient had a complicated MD with an unique combination of risk factors and findings. PRESENTATION OF CASE: We report an unusual case of an 18-year-old patient presenting with acute small bowel obstruction for several days, who developed focal peritoneal signs on right lower quadrant. On laparotomy, findings included a necrotic giant MD and a small bowel volvulus around a fibrous band that attached MD to the umbilicus. Segmental enterectomy with primary anastomosis was performed. DISCUSSION: Axial torsion and gangrene of MD is the rarest complication. Its pre-operative diagnosis remains elusive as it can be clinically indistinguishable from other intra-abdominal inflammatory conditions. The correct diagnosis of complicated MD before surgery is often difficult because this condition can mimic other acute abdominal pathologies. There are several risk factors that can point to an accurate and early diagnosis, especially when combined with the appropriate imaging techniques, such as computed tomography with oral and intravenous contrast. CONCLUSION: This complication remains underdiagnosed, often with delayed surgical intervention and sub-optimal treatment that leads to significant morbidity and mortality.