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The successful adoption of information and communication technology to enhance learning can be very challenging, requiring a complex blend of technological, pedagogical and organizational components, which may at times require the resolution of contradictory demands and conflicting needs. The research reported in this paper investigated and analysed critical success factors (CSFs) that are required to deliver e-learning within higher education (HE) courses and programmes. The research design adopted a critical research approach, instantiated by focus group discussions with e-learning experts drawn from administrative, educational, technology and research domains. The findings revealed that staffing issues, pedagogically sound delivery models and training of both tutors and students cannot be treated as trivial issues and are critical to the success of e-learning. Furthermore, this research also shows that there is a strong relationship between these factors and inspirational institutional leadership. The findings also suggest that in order to assure the success of e-learning, this leadership should guarantee the presence of institutional enablers. It is hoped that the CSFs, described and discussed in depth in this paper, will provide a suitable theoretical foundation to underpin the successful delivery of e-learning within HE. (Contains 3 figures and 4 tables.)

Two-phase olive mill waste (TPOMW) is a by-product of olive oil extraction, contains up to 90% organic matter, and may be used as soil amendment. To investigate the impact of TPOMW amendments to soil on the fractionation, adsorption, and buffering capacity of P, experiments were conducted on soils collected from a typical olive grove amended for 5 yr with 0, 30, and 60 Mg [ha.sup.-1] of TPOMW. A modified Hedley fractionation scheme evaluated the change in soil P forms while surface models were used to fit the data. The P fractionation results suggested and increase in HCl-P fraction. Other P pools, such as residual-P, NaHC[O.sub.3]-Pi, NaOH-Pi, NaOHPo, soluble-P, and NaHC[O.sub.3]--Po increased to lesser degrees. A two-surface Langmuir model fit the adsorption data better than a uniform layer model and underestimation of the P adsorption was observed when the traditional Langmuir equation was used. The TPOMW amendments significantly decreased the P adsorption maxima ([alpha] = 0.05) and most of the P was adsorbed on low energy sites, independent of the amendment applications received. The TPOMW soil application decreased indices of P-binding intensity at both high and low affinity sites, decreased the P equilibrium buffering capacity, and increased the equilibrium P concentration (EPC). Coupled with the low energy of P binding, results implied an increase in the readily soluble P, and thus runoff P losses could potentially increase in TPOMW amended soil. Abbreviations: EBC, equilibrium buffering capacity; EPC, equilibrium P concentration; Pi, inorganic P forms; Po, organic P forms; Q/I, quantity/intensity; TP, total P; TPOMW. two-phase olive mill waste; WSOC, water-soluble organic carbon.

Semiarid Mediterranean soils under intensive continuous cultivation have a net deficit of C, and addition of organic wastes is becoming a common practice as a disposal strategy and an interesting solution to redress this deficiency. A 2-yr greenhouse study using wheat (Triticum aestivum L.) was conducted to evaluate the potential use of the final solid waste of the new technology of olive-oil extraction (de-oiled two-phase olive mill waste, DTPOMW) as a soil conditioner and amendment agent. Two representative Mediterranean agricultural soils, a Typic Haploxeralf (TH) and a degraded Lithic Xerorthent (LX) were used. Treatments included five DTPOMW rates ranging from 0 to 40 Mg [ha.sup.-1] combined with mineral fertilizer. Significant direct and residual increases in organic C, total N, available K, cation exchange capacity, and aggregate stability were observed in both soils; however, available P decreased significantly. In the first year of the experiment, an application of 40 Mg DTPOMW [ha.sup.-1] had a depressive effect on grain yield and on the N and P content in the wheat grain for the LX soil, while in the TH soil there was a positive effect on yield at the same loading rate. There was an increased residual fertilization and amendment effect of DTPOMW for both soils during the second experimental year, and the grain yields increased by 23 and 202% when 40 Mg DTPOMW [ha.sup.-1] was applied to the TH and LX soils, respectively. For both soils, the best fits to grain yield vs. DTPOMW rates were with a quadratic regression ([R.sup.2] = 0.977, P < 0.001 for TH; [R.sup.2] = 0.983, P < 0.001 for LX). Raw DTPOMW may be a potentially valuable soil amendment agent and source of organic matter, N, and K because it maintains a positive, beneficial effect on wheat grain yield and soil properties for 24 mo following application. Abbreviations: CEC, cation exchange capacity; DTPOMW, de-oiled two-phase olive mill waste; LX, Lithic Xerorthent; OC, organic carbon; TH, Typic Haploxeralf; TPOMW, two-phase olive mill waste.

Two-phase olive mill waste (TPOMW) and dairy cattle slurry (CS) are two organic materials with low economic value and limited potential for reutilization despite their high concentrations of nitrogen (N) and organic matter. A laboratory incubation for ca. 100 d was performed to assess the short-term N and carbon (C) dynamics in a soil amended with TPOMW, CS and a mixture of both materials in order to: (i) explore the potential benefits of mixing TPOMW with CS to promote mineral N immobilization and avoid nitrate leaching, and (ii) assess the potential for increased soil C stocks after TPOMW, CS or TPOMW+CS application. Our results clearly showed that the combined application of TPOMW+CS caused N immobilization; hence, it contributes to tying up the applied N, resulting in a decrease of critical N leaching, which is usually observed after CS application. No clear N mineralization was observed in the TPOMW+CS treatment during the incubation period. It appears that an application of 30 Mg ha−1of TPOMW is enough to decrease net N mineralization from applied CS, as the C:N ratio of the mixture TPOMW+CS is 27. More than 40% of the TPOMW-derived C remained in the soil at the end of the experiment in treatments with single and combined application of TPOMW+CS, indicating that such materials have the potential to increase C stocks in soil. It can be concluded that a combined application of TPOMW+CS is of interest to maintain the CS-derived N in organic form during a longer time period and minimize risks of nitrate leaching, although further studies are necessary to define a better TPOMW:CS ratio which allows a proper plant N uptake. [ABSTRACT FROM PUBLISHER]

Within the framework of the EU-funded HLA-NET action, an analysis of three G-group alleles, HLA-B*44:02:01G, DRB1*14:01:01G and DQB1*03:01:01G, was undertaken in 12 European populations. Ambiguities were resolved by polymerase chain reaction-sequence-specific amplification (PCR-SSP) or PCR-sequence-based typing (PCR-SBT) in a total of 5095 individuals. The results of the DRB1*14:01/14:54 ambiguity showed high relative ratios (24-53%) of DRB1*14:01 in Bulgarians, Croatians, Greeks, Italians and Slovenians, contrasting with low ratios (6-13%) in Austrians, Finnish, French, Hungarians, Norwegians and Swiss. Resolution of the B*44:02/44:27 ambiguity showed that B*44:27 had a high relative ratio in Slovenians (25.5%) and Bulgarians (37%) and low in French and Swiss (0.02-1%), and was not observed in Greeks and Italians. The highest relative ratio of DQB1*03:19 was found in Portuguese (11%), by contrast with low ratios (0-3%) in the other five populations. Analysis of the A, B, DRB1 phenotypes and family-derived haplotypes in 1719 and 403 individuals positive for either HLA-B*44:02G or DRB1*14:01G ambiguities, respectively, showed some preferential associations, such as A*26∼DRB1*14:01, B*35∼DRB1*14:01, B*38∼DRB1*14:01 and B*44:27∼DRB1*16. Because these ambiguities are located outside the peptide-binding site, they may not be recognized by alloreactive T-cells. However, because of strong linkage disequilibrium (LD), the DRB1*14:01 vs DRB1*14:54 and the B*44:02 vs B*44:27 mismatches are associated to DRB3-, and C-mismatches, respectively. These results are informative for algorithms searching unrelated hematopoietic stem cell donors. For B*44:27-positive patients, searches are expected to be more successful when requesting donors from Southeastern-European ancestry. Furthermore, the introduction of human leukocyte antigen (HLA)-typing strategies that allow resolving exon 4 (for class I) and exon 3 (for class II) polymorphisms can be expected to contribute significantly to population genetics studies. [ABSTRACT FROM AUTHOR]