Green and animal manure use in organic field crop systems

Dual-use cover/green manure (CGM) crops and animal manure are used to supply nitrogen (N) and phosphorus (P) to organically grown field crops. A comprehensive review of previous research was conducted to identify how CGM crops and animal manure have been used to meet N and P needs of organic field crops, and to identify knowledge gaps to direct future research efforts. Results indicate that: (a) CGM crops are used to provide N to subsequent cash crops in rotations; (b) CGM-supplied N generally can meet field crop needs in warm, humid regions but is insufficient for organic grain crops grown in cool and sub-humid regions; (c) adoption of conservation tillage practices can create or exacerbate N deficiencies; (d) excess N and P can result where animal manures are accessible if application rates are not carefully managed; and (e) integrating animal grazing into organic field crop systems has potential benefits but is generally not practiced. Work is needed to better understand the mechanisms governing the release of N by CGM crops to subsequent cash crops, and the legacy effects of animal manure applications in cool and sub-humid regions. The benefits and synergies that can occur by combining targeted animal grazing and CGMs on soil N, P, and other nutrients should be investigated. Improved communication and networking among researchers can aid efforts to solve soil fertility challenges faced by organic farmers when growing field crops in North America and elsewhere

[Phlebography with MR in the study of deep venous thrombosis]

MR phlebography was recently proposed as a possible alternative to contrast venography in the detection of deep venous thrombosis. We focused our work on the study of the pelvic veins since it is at this level that contrast venography and the other noninvasive techniques, i.e., phlebography, impedance plethysmography and US, exhibit their major limitations. Thirty patients underwent MR phlebography: 13 of them had a diagnosis of DVT of the pelvic venous district and the other 17 had negative results for this condition. All the patients were also examined with color-Doppler US at the pelvis and legs. In all the patients submitted to MR phlebography, thrombosis site and presence were demonstrated, with diagnostic information also on its extent and adhesion to vein wall. To conclude, MR phlebography can provide contrast venography-like images in a noninvasive way, with high accuracy (100% sensitivity and 90% specificity) especially in the pelvic district where the limitations of other techniques are more apparent. Larger series of patients must be studied to assess the actual role of MR phlebography in the patients with DVT or at high risk for this condition

Restorative proctocolectomy: morphological and functional study with coronal CT.

BACKGROUND: Restorative proctocolectomy with ileal pouch has become the surgical treatment of choice for patients with ulcerative colitis (UC) and familial polyposis of the colon. Defecography is the radiological technique commonly employed to obtain detailed information on function and morphology of the ileal pouch; it allows the direct visualization of the ileal pouch and the anal canal, but it does not provide the visualization of the pelvis. METHODS: In all patients, computed tomography (CT) on coronal planes was performed to determine its possibilities as an alternative to defecography; 10 patients with UC submitted to restorative proctocolectomy and were examined. RESULTS: Coronal CT images provided a panoramic vision of the pelvis and demonstrated the morphology of the ileal pouch, the thickness of its walls, and its correlation with the surrounding tissues. Coronal CT also allowed the evaluation of the continence of ileo-anal and ileo-ileal anastomosis and the functional changes of the perineal muscles at rest and during squeezing. CONCLUSION: CT images acquired on coronal planes allows an easy and clear detection of the major postoperative complications, such as stenosis or dehiscences of the anastomosis, pelvic phlogosis, and fistulae