For the Cucumber, Celeriac and Citrus Salad: In a non-reactive saucepan, reduce the orange juice by 80 percent, until a syrupy consistency is reached. Set aside. In a bowl, whisk together the Dijon, soy, vinegar and olive oil. Season with salt and pepper. Toss some of the vinaigrette to coat the celeriac and the rest to coat the cucumbers. Check for seasoning. Using a stainless steel or plastic o-ring (3-inch diameter, 2 inches tall), line with cucumbers then fill with celeriac salad. In a saute pan, add olive oil and caramelize scallions. Add shrimp and season. Cook for 3 minutes and add the citrus, just to warm, 1 minute. Check for seasoning. Top celeriac with warm shrimp. Remove o-ring and drizzle orange syrup around.