Peatland-fire interactions: A review of wildland fire feedbacks and interactions in Canadian boreal peatlands

Boreal peatlands store a disproportionately large quantity of soil carbon (C) and play a critical role within the global C-climate system; however, with climatic warming, these C stores are at risk. Increased wildfire frequency and severity are expected to increase C loss from boreal peatlands, contributing to a shift from C sink to source. Here, we provide a comprehensive review of pre- and post-fire hydrological and ecological interactions that affect the likelihood of peatland burning, address the connections between peatland fires and the C-climate cycle, and provide a conceptual model of peatland processes as they relate to wildland fire, hydro-climate, and ecosystem change. Despite negative ecohydrological feedback mechanisms that may compensate for increased C loss initially, the cumulative effects of climatic warming, anthropogenic peatland fragmentation, and subsequent peatland drying will increase C loss to the atmosphere, driving a positive C feedback cycle. However, the extent to which negative and positive feedbacks will compensate for one another and the timelines for each remains unclear. We suggest that a multi-disciplinary approach of combining process knowledge with remotely sensed data and ecohydrological and wildland fire models is essential for better understanding the role of boreal peatlands and wildland fire in the global climate system.

Monitoring ecosystem reclamation recovery using optical remote sensing: Comparison with field measurements and eddy covariance

Time series remote sensing vegetation indices derived from SPOT 5 data are compared with vegetation structure and eddy covariance flux data at 15 dry to wet reclamation and reference sites within the Oil Sands region of Alberta, Canada. This comprehensive analysis examines the linkages between indicators of ecosystem function and change trajectories observed both at the plot level and within pixels. Using SPOT imagery, we find that higher spatial resolution datasets (e.g. 10 m) improves the relationship between vegetation indices and structural measurements compared with interpolated (lower resolution) pixels. The simple ratio (SR) vegetation index performs best when compared with stem density-based indicators (R² = 0.65; p < 0.00), while the normalised difference vegetation index (NDVI) and soil adjusted vegetation index (SAVI) are most comparable to foliage indicators (leaf area index (LAI) and canopy cover (R² = 0.52-0.78; p > 0.02). Fluxes (net ecosystem production (NEP) and gross ecosystem production (GEP)) are most related to NDVI and SAVI when these are interpolated to larger 20 m × 20 m pixels (R² = 0.44-0.50; p < 0.00). As expected, decreased sensitivity of NDVI is problematic for sites with LAI > 3 m² m^-2, making this index more appropriate for newly regenerating reclamation areas. For sites with LAI < 3 m² m^-2, trajectories of vegetation change can be mapped over time and are within 2.7% and 3.3% of annual measured LAI changes observed at most sites. This study demonstrates the utility of remote sensing in combination with field and eddy covariance data for monitoring and scaling of reclaimed and reference site productivity within and beyond the Oil Sands Region of western Canada.

A painless treatment for patients undergoing Milligan-Morgan haemorrhoidectomy

BACKGROUND

Postoperative pain associated with Milligan Morgan haemorrhoidectomy (MMH) remains problematic. Most patients complaint a severe pain on defecation and in the 1st postoperative week because of secondary infection and sphincter spasm. We studied the effect of metronidazole, lactulose and glyceryl-trinitrate on pain after MMH.

METHOD

Thirty patients were randomly assigned to two groups. The 1st received a treatment with oral laxative (lactulose 66.7%) metronidazole and a topical glyceryl-trinitrate ointment at 0.2% both pre and postoperative; the 2nd received a placebo at the same dosage. The amount of pain in the 1st week and at the time of two defecation, postoperative analgesic requirement and time to return to normal activities were documented.

RESULTS

A significant differences in the score pain on 2nd and 3rd day and on the 1st two defecation were observed among group. Analgesic consumption was highest in the placebo group.

CONCLUSION

The treatment with lactulose, metronidazole and topic glyceryl-trinitrate in patients undergoing MMH, seems to reduce secondary pain and increase patients satisfaction and earlier return to work with improvement of cost and benefit.

[Milligan-Morgan haemorrhoidectomy with ultrasonic scalpel]

INTRODUCTION

Milligan-Morgan haemorrhoidectomy is considered the best treatment for hemorrhoidal disease. Although this, many patients complaint post-operative pain that remain the worse complication. For this reason different are the trials performed in order to reduce his intensity. In this report we want to evaluate if the use of ultrasonic scalpel to perform Milligan-Morgan hemorrhoidectomy, compared with conventional surgery, could reduce post-operative pain.

MATERIALS AND METHODS

30 patients with III and IV degree of haemorrhoids were included in this study and divided in two groups. In the first group Milligan-Morgan haemorrhoidectomy was performed with conventional instruments, while in the second group the some procedure was performed with ultrasonic scalpel. The duration of intervention, time hospitalization, the time to open alvus to stools, the time to return to normal activity, the complications, pain and the amount of analgesic consumption were evaluated.

RESULTS

In the II group's patients, it was observed a reduced time to healing with reduced spread of necrosis and inflammatory pattern, associated with reduced post-operative pain and the lower analgesic consumption.

CONCLUSIONS

The use of ultrasonic scalpel to perform Milligan-Morgan haemorrhoidectomy, compared with conventional instruments, reduce post-operative pain making a more short time to healing and a precocious time to return to normal activity. For this reason we believe that the use of ultrasonic scalpel, although a more elevated costs, seems to be advantageous.

[Bacterial endocarditis. Unusual complications of acute diverticulitis]

BACKGROUND

Colon diverticular disease represents an affection with high prevalence in the western countries. It appears particularly insidious in the elderly population for the presence of concomitant illnesses.

CLINICAL CASE

A patient (> 80 years old) is submitted to surgical intervention in emergency sec. Hartman for acute diverticulitis and pelvic abscess. The post-operating time has been complicated for the arising of a fever resistant to the common antibiotic therapy, in absence of abdominal and respiratory objectivity. An accurate clinical examination has set the suspect of bacterial endocarditis, confirmed to the echocardiographic examination.

DISCUSSION

The acute complicated diverticulitis therapy variates in according to the clinical presentation, the complications and the experience of the different Authors. A first conservative approach foresees the Total Parenteral Nutrition (TPN) and the wide spectrum antibiotic therapy and the eventual percutaneous drainage. The surgical treatment, realized with "open" or laparoscopic method, foresees the resection of the sick intestinal tract and the packing of a temporary preternatural anus. However, some Authors prefer an intestinal anastomosis performed in single time with the resection. Among all the complications, the most frequent are those affecting the respiratory and cardiovascular apparatus, as well as the sepsis. The bacterial endocarditis is not signalled in most recent international Literature.

CONCLUSION

The bacterial endocarditis must be suspected in case of common antibiotic therapy resistant fever, with negative abdominal and pulmonary objectivity, arising after a septic surgical intervention.