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Existing accumulation maps with reported errors of about 20% are determined from sparsely distributed ice cores and pits. A more accurate accumulation rate might be obtained by generating continuous profiles of dated layers from high-resolution radar mapping of near-surface internal layers in the ice sheet (isochrones). To generate such profiles we designed and developed an ultrawideband radar for high-resolution mapping of internal layers in the top 200 m of ice and tested it at the North Greenland Ice Core Project drill site. Reflection profiles of 2- and 10-km length reveal horizons that we correlate with electrical conductivity measurement (ECM) recordings. Our results show that the radar-determined depth of internal layers is within ±2 m of that in an ice core collected at a nearby location. Preliminary frequency analyses of layer reflections reveal that the reflections are strongest at the 500–1000 MHz frequency range. Long-term accumulation rate computed from radar data is within 5% of that obtained from snow pits.

A key variable in assessing the mass balance of an ice sheet is accumulation rate. Currently, accumulation rate is determined from sparsely distributed ice cores and pits. There are uncertainties in existing accumulation rates derived from these cores and pits. The authors developed an ultra wideband frequency modulated continuous wave (FMCW) radar for mapping internal layers, from known volcanic events, in the ice for estimating accumulation rate from high-resolution radar data. The authors tested the radar system during the 1998 surface experiment at the North Greenland Ice core Project (NGRIP) ice camp. Their results show that internal layers were mapped with high resolution down to 200 m. In this paper, they present the results of the 1998 NGRIP surface experiment.

The global sea level rise has been attributed to the melting of mountain glaciers among other causes. The mass balance of the glacial ice plays an important role in the rise of the Earth's sea level. A key variable in assessing the mass balance of an ice sheet is accumulation rate, which is currently determined from ice cores and pits. Accumulation data are sparse, and there are large uncertainties in existing accumulation rate maps derived from sparely distributed ice cores and pits. The accumulation rate can be estimated more accurately if we are able to obtain a continuous profile of the dated layers in the ice sheet. The authors describe the development of a high-resolution radar system to map the layers in the ice sheet and present the results obtained at the North GReenland Ice core Project (NGRIP) ice camp with their prototype system.

Previous to October 1st, 1981, 8 major Danish anaesthesiological departments registered 105 patients treated with extradural opiates for a period of more than 7 days, partially or completely on outpatient basis. Ninety-four suffered from painful malignant diseases and 11 patients from various painful benign diseases. The mean period of treatment was 65 days (range: 7-283 days) and of these 49 days (2-266 days) as outpatients. The total number of inserted epidural catheters was 215, equivalent of an average of 2 per patient (range 1-5). Reasons for removing an extradural catheter were injection-related pain, difficulty in injecting the desired volume, and displacement of catheter. Morphine chloride, in a solution of 0.4 mg/ml of normal saline, was the main choice as analgesic agent (90 patients). The mean daily dose of this drug totalled 12.6 +/- 4.8 mg (S.D.) (range: 4-30 mg) distributed as 2.7 +/- 0.9 (S.D.) (range: 1-6) daily injections. Twelve patients were treated with buprenorphine extradurally. Satisfactory pain relief was achieved for 70 patients (67%) who managed with extradural opiates as sole analgesic treatment. One patient developed septicaemia with a non-fatal outcome probably originating from some other focus. Apart from this no serious side effects were reported. Medically unskilled persons or relatives were responsible for instillation of all extradural opiates with 42 patients and partially responsible with 14 patients. Eleven patients managed injections without assistance. District nurses took care of medication for 46 patients, aided by a general practitioner in 5 cases. Three patients were supplied with continuous extradural infusion by means of a Mill Hill microinfusion pump.

The adenosine analogue 3-deazaadenosine (c3 Ado) induces differentiation of human promyelocytic leukemia HL-60 cells in vitro. c3 Ado affects in vitro viability and growth of cells involved indirectly (cytokine-producing cells) and directly (transformed myeloid cells) in leukemic cell differentiation. Growth inhibition of proliferating cells is achieved at c3 Ado concentrations between 10-100 microM. Concentrations higher than 100 microM affect viability of proliferating and nonproliferating cells.

The North Greenland Icecore Project (NorthGRIP) was initiated in 1995 as a joint international programme involving Denmark, Germany, Japan, Belgium, Sweden, Iceland, the U.S.A., France and Switzerland. the main goal was to obtain undisturbed high-resolution information about the Eemian climatic period (115–130 kyr BP). the records from the Greenland Icecore Project (GRIP) and Greenland Ice Sheet Project 2 (GISP2) in central Greenland are different and disturbed down in the ice covering this period. Internal radio-echo sounding layers show that NorthGRIP, placed 325 km north-northwest of GRIP at the Summit of the Greenland ice sheet, is located on a gently sloping ice ridge with very flat bedrock and internal layers found so high that an undisturbed Eemian record is possible. Internal layers much farther above bedrock than their apparent counter parts at GRIP suggest that conditions are favourable for recovery of an undisturbed Eemian record. So far, a 1351 mdeep ice core (NorthGRIP1) and a 3001 mdeep ice core (NorthGRIP 2) have been recovered. the ice thickness is expected to be 3080 m, and the ice temperature at 3001 m is –5.6°C, so we expect basal melting at the bedrock. Most of the Eemian ice will be melted away, leaving only the last part and the transition between the Eem and the Last Glacial Period. At 3001 m the age of the ice is 110 kyr BP and the annual layers are of the order 1 cm.With modern methods the annual layers can be resolved, resulting in detailed information on the decline of the warm Eemian period into the Last Glacial Period.