Telemedicine and cystic fibrosis: Do we still need face-to-face clinics?

There has been growing interest in telemedicine for cystic fibrosis over recent years based largely on convenience for patients and/or increasing the frequency of surveillance and early detection which, it is assumed, could improve treatment outcomes. During 2020, the covid-19 pandemic catalysed the pace of development of this field, as CF patients were presumed to be at high risk of infection. Most clinics adapted to digital platforms with provision of lung function monitoring and sample collection systems. Here, we present the views of multidisciplinary team members at a large paediatric CF centre on what has worked well and what requires further optimisation in the future. In response to the question posed, 'Do we still need face to face clinics?' our answer is 'Yes, but not every time, and not for everyone'.

High altitude hunting, climate change, and pastoral resilience in eastern Eurasia.

The transition from hunting to herding transformed the cold, arid steppes of Mongolia and Eastern Eurasia into a key social and economic center of the ancient world, but a fragmentary archaeological record limits our understanding of the subsistence base for early pastoral societies in this key region. Organic material preserved in high mountain ice provides rare snapshots into the use of alpine and high altitude zones, which played a central role in the emergence of East Asian pastoralism. Here, we present the results of the first archaeological survey of melting ice margins in the Altai Mountains of western Mongolia, revealing a near-continuous record of more than 3500 years of human activity. Osteology, radiocarbon dating, and collagen fingerprinting analysis of wooden projectiles, animal bone, and other artifacts indicate that big-game hunting and exploitation of alpine ice played a significant role during the emergence of mobile pastoralism in the Altai, and remained a core element of pastoral adaptation into the modern era. Extensive ice melting and loss of wildlife in the study area over recent decades, driven by a warming climate, poaching, and poorly regulated hunting, presents an urgent threat to the future viability of herding lifeways and the archaeological record of hunting in montane zones.

Diabetes management during cardiac surgery in the UK: A survey.

AIM: To determine current practice regarding the diabetes management of people undergoing cardiac surgery in the UK. METHODS: We conducted an online survey of UK cardiothoracic surgeons. All cardiothoracic surgeons listed in the Society of Cardiothoracic Surgery membership directory were invited to participate. The survey, compiled using SurveyMonkey software, comprised 15 closed and open-ended questions about the management of people with diabetes pre- and peri-operatively. RESULTS: Sixty-two cardiothoracic surgeons from all 33 UK cardiac centres completed the survey. Of these, 44% responded that they routinely measure HbA1c preoperatively for all patients, 19% had an HbA1c threshold above which they would not operate and 21% currently undertake a point-of-care HbA1c measurement during the cardiothoracic outpatient visit. A total of 74% of respondents reported that it was 'easy' or 'very easy' to obtain a diabetes team review; diabetes nurse specialists were the members of the diabetes team working most closely with cardiac surgeons. Up to a third of the surgeons did not provide physical activity recommendations prior to admission and over 80% did not have a different preoperative or surgical diabetes protocol. Inconsistency in the responses within centres suggests that differences in practice may depend on individual surgeons rather than local policy. CONCLUSIONS: The study demonstrates there is only limited peri-operative management of diabetes in people undergoing cardiac surgery in the UK. There is an opportunity for greater involvement of the diabetes specialist team both before and during admission for surgery to improve outcomes. (Trial registration: ISRCTN10170306).

Investigating reindeer pastoralism and exploitation of high mountain zones in northern Mongolia through ice patch archaeology.

In interior Eurasia, high mountain zones are crucial to pastoral subsistence, providing seasonally productive pastures and abundant wild resources. In some areas of northern Mongolia, mountainous tundra zones also support a low-latitude population of domestic reindeer herders-a lifestyle whose origins are poorly characterized in the archaeological record of early Mongolia. Traditionally, reindeer pastoralists make significant seasonal use of munkh mus (eternal ice) for their domestic herds, using these features to cool heat-stressed animals and provide respite from insect harassment. In recent years, many of these features have begun to melt entirely for the first time, producing urgent threats to traditional management techniques, the viability of summer pastures, and reindeer health. The melting ice is also exposing fragile organic archaeological materials that had previously been contained in the patch. We present the results of horseback survey of ice patches in Baruun Taiga special protected area, providing the first archaeological insights from the region. Results reveal new evidence of historic tool production and wild resource use for fishing or other activities, and indicate that ice patches are likely to contain one of the few material records of premodern domestic reindeer use in Mongolia and lower Central Asia. The area's ancient ice appears to be rapidly melting due to changing climate and warming summer temperatures, putting both cultural heritage and traditional reindeer herding at extreme risk in the years to come.

Ancient individuals from the North American Northwest Coast reveal 10,000 years of regional genetic continuity.

Recent genomic studies of both ancient and modern indigenous people of the Americas have shed light on the demographic processes involved during the first peopling. The Pacific Northwest Coast proves an intriguing focus for these studies because of its association with coastal migration models and genetic ancestral patterns that are difficult to reconcile with modern DNA alone. Here, we report the low-coverage genome sequence of an ancient individual known as "Shuká Káa" ("Man Ahead of Us") recovered from the On Your Knees Cave (OYKC) in southeastern Alaska (archaeological site 49-PET-408). The human remains date to ∼10,300 calendar (cal) y B.P. We also analyze low-coverage genomes of three more recent individuals from the nearby coast of British Columbia dating from ∼6,075 to 1,750 cal y B.P. From the resulting time series of genetic data, we show that the Pacific Northwest Coast exhibits genetic continuity for at least the past 10,300 cal y B.P. We also infer that population structure existed in the late Pleistocene of North America with Shuká Káa on a different ancestral line compared with other North American individuals from the late Pleistocene or early Holocene (i.e., Anzick-1 and Kennewick Man). Despite regional shifts in mtDNA haplogroups, we conclude from individuals sampled through time that people of the northern Northwest Coast belong to an early genetic lineage that may stem from a late Pleistocene coastal migration into the Americas.

Three-point transfusion risk score in hepatectomy.

BACKGROUND: Perioperative red blood cell transfusions are required in up to 23 per cent of patients undergoing hepatectomy. Previous research has developed three transfusion risk scores to assess risk of perioperative red blood cell transfusion. Here, the performance of these transfusion risk scores was evaluated in a multicentre cohort of patients who underwent hepatectomy and compared with that of a simplified transfusion risk score. METHODS: A database of patients undergoing hepatectomy at four specialized centres between 2008 and 2012 was developed. External validity was assessed by discrimination and calibration. Discrimination was evaluated using the area under the receiver operating characteristic (ROC) curve (AUC). Calibration was evaluated by the degree of agreement between predicted and actual red blood cell transfusion probabilities. A simplified transfusion risk score using variables common to the three models was created, and discrimination and calibration were evaluated. RESULTS: There were 1287 patients included in this study, with 341 (26·5 per cent) receiving a red blood cell transfusion. Discriminative ability was similar between the three transfusion risk scores, with AUCs of 0·66-0·68 and good calibration. A new three-point risk score was developed based on factors present in all models: haemoglobin 12·5 g/dl or less, primary liver malignancy and major resection (at least 4 segments). Discriminative ability and calibration of the three-point model were similar to those of the three existing models, with an AUC of 0·66. CONCLUSION: The three-point transfusion risk score simplifies assessment of perioperative transfusion risk in hepatectomy without sacrificing predictive ability.

Sediment-associated organic matter sources and sediment oxygen demand in a Special Area of Conservation (SAC): A case study of the River Axe, UK.

Oxygen demand in river substrates providing important habitats for the early life stages of aquatic ecology, including lithophilous fish, can arise due to the oxidation of sediment-associated organic matter. Oxygen depletion associated with this component of river biogeochemical cycling, will, in part, depend on the sources of such material. A reconnaissance survey was therefore undertaken to assess the relative contributions from bed sediment-associated organic matter sources potentially impacting on the River Axe Special Area of Conservation (SAC), in SW England. Source fingerprinting, including Monte Carlo uncertainty analysis, suggested that the relative frequency-weighted average median source contributions ranged between 19% (uncertainty range 0-82%) and 64% (uncertainty range 0-99%) for farmyard manures or slurries, 4% (uncertainty range 0-49%) and 35% (uncertainty range 0-100%) for damaged road verges, 2% (uncertainty range 0-100%) and 68% (uncertainty range 0-100%) for decaying instream vegetation, and 2% (full uncertainty range 0-15%) and 6% (uncertainty range 0-48%) for human septic waste. A reconnaissance survey of sediment oxygen demand (SOD) along the channel designated as a SAC yielded a mean SOD5 of 4 mg O2 g-1 dry sediment and a corresponding SOD20 of 7 mg O2 g-1 dry sediment, compared with respective ranges of 1-15 and 2-30 mg O2 g-1 dry sediment, measured by the authors for a range of river types across the UK. The findings of the reconnaissance survey were used in an agency (SW region) catchment appraisal exercise for informing targeted management to help protect the SAC.

Long-term management changes topsoil and subsoil organic carbon and nitrogen dynamics in a temperate agricultural system.

Soil organic carbon (SOC) and nitrogen (N) contents are controlled partly by plant inputs that can be manipulated in agricultural systems. Although SOC and N pools occur mainly in the topsoil (upper 0.30 m), there are often substantial pools in the subsoil that are commonly assumed to be stable. We tested the hypothesis that contrasting long-term management systems change the dynamics of SOC and N in the topsoil and subsoil (to 0.75 m) under temperate conditions. We used an established field experiment in the UK where control grassland was changed to arable (59 years before) and bare fallow (49 years before) systems. Losses of SOC and N were 65 and 61% under arable and 78 and 74% under fallow, respectively, in the upper 0.15 m when compared with the grass land soil, whereas at 0.3-0.6-m depth losses under arable and fallow were 41 and 22% and 52 and 35%, respectively. The stable isotopes 13C and 15N showed the effects of different treatments. Concentrations of long-chain n-alkanes C27, C29 and C31 were greater in soil under grass than under arable and fallow. The dynamics of SOC and N changed in both topsoil and subsoil on a decadal time-scale because of changes in the balance between inputs and turnover in perennial and annual systems. Isotopic and geochemical analyses suggested that fresh inputs and decomposition processes occur in the subsoil. There is a need to monitor and predict long-term changes in soil properties in the whole soil profile if soil is to be managed sustainably. HIGHLIGHTS: Land-use change affects soil organic carbon and nitrogen, but usually the topsoil only is considered.Grassland cultivated to arable and fallow lost 13-78% SOC and N to 0.6 m depth within decades.Isotopic and biomarker analyses suggested changes in delivery and turnover of plant-derived inputs.The full soil profile must be considered to assess soil quality and sustainability.

Expert opinion on advanced techniques for hemostasis in liver surgery.

BACKGROUND: Reduction of perioperative blood loss and intraoperative transfusion are two major factors associated with improving outcomes in liver surgery. There is currently no consensus as to the best technique to achieve this. METHODS: An international Panel of Experts (EP), made up of hepatobiliary surgeons from well-known high-volume centres was assembled to share their experience with regard to the management of blood loss during liver resection surgery. The process included: a review of the current literature by the panel, a face-to-face meeting and an on-line survey completed by the EP prior to and following the face-to-face meeting, based on predetermined case scenarios. During the meeting the most frequently researched surgical techniques were appraised by the EP in terms of intraoperative blood loss. RESULTS: All EP members agreed that high quality research on the subject was lacking. Following an agreed risk stratification algorithm, the EP concurred with the existing research that a haemostatic device should always be used along with any user preferred surgical instrumentation in both open and laparoscopic liver resection procedures, independently from stratification of bleeding risk. The combined use of Ultrasonic Dissector (UD) and saline-coupled bipolar sealing device (Aquamantys(®)) was the EP preferred technique for both open and laparoscopic surgery. CONCLUSIONS: This EP propose the use of a bipolar sealer and UD for the best resection technique and essential equipment to minimise blood loss during liver surgery, stratified according to transfusion risk, in both open and laparoscopic liver resection.

Characterization of Colletotrichum Species Causing Bitter Rot of Apple in Kentucky Orchards.

Multiple species of Colletotrichum can cause bitter rot disease of apple, but the identities and relative representation of the species causing the disease in Kentucky are unknown. In total, 475 Colletotrichum isolates were collected from diseased apple fruit in 25 counties and characterized both morphologically and by using various molecular approaches. Multigene sequence analyses revealed that sample isolates belonged to several newly erected species within the Colletotrichum acutatum and C. gloeosporioides species complexes. The isolates were identified as C. fioriniae and C. nymphaeae, which reside within the C. acutatum species complex, and C. siamense, C. theobromicola, and C. fructicola, which are placed within the C. gloeosporioides species complex. C. fioriniae was the most common species causing bitter rot in Kentucky, comprising more than 70% of the isolates. Infectivity tests on detached fruit showed that C. gloeosporioides species-complex isolates were more aggressive than isolates in the C. acutatum species complex. However, isolates within the C. acutatum species complex produced more spores on lesions compared with isolates within the C. gloeosporioides species complex. Aggressiveness varied among individual species within a species complex. C. siamense was the most aggressive species identified in this study. Within the C. acutatum species complex, C. fioriniae was more aggressive than C. nymphaeae, causing larger, deeper lesions. Apple cultivar did not have a significant effect on lesion development. However, Colletotrichum spp. produced more spores on 'Red Stayman Winesap' than on 'Golden Delicious'. Fungicide sensitivity tests revealed that the C. acutatum species complex was more tolerant to thiophanate-methyl, myclobutanil, trifloxystrobin, and captan compared with the C. gloeosporioides species complex. The study also revealed that mycelial growth of C. siamense was more sensitive to tested fungicides compared with C. fructicola and C. theobromicola. These research findings emphasize the importance of accurate identification of Colletotrichum spp. within each species complex, because they exhibit differences in pathogenicity and fungicide sensitivity.

Hepatic arterial infusion pump chemotherapy in the management of colorectal liver metastases: expert consensus statement.

Despite significant improvements in systemic therapy for patients with colorectal liver metastases (crlms), response rates in the first-line setting are not optimal, and response rates in the second-line setting remain disappointing. Hepatic arterial infusion pump (haip) chemotherapy has been extensively studied in patients with crlms, but it remains infrequently used. We convened an expert panel to discuss the role of haip in the contemporary management of patients with crlm. Using a consensus process, we developed these statements: haip chemotherapy should be given in combination with systemic chemotherapy.haip chemotherapy should be offered in the context of a multidisciplinary program that includes expertise in hepatobiliary surgery, medical oncology, interventional radiology, nursing, and nuclear medicine.haip chemotherapy in combination with systemic therapy should be considered in patients with unresectable crlms who have progressed on first-line systemic treatment. In addition, haip chemotherapy is acceptable as first-line treatment in patients with unresectable colorectal liver metastases.haip chemotherapy is not recommended in the setting of extrahepatic disease outside the context of a clinical trial.haip chemotherapy in combination with systemic therapy is an option for select patients with resected colorectal liver metastases. These consensus statements provide a framework that clinicians who treat patients with crlm can use when considering treatment with haip.

Catchment source contributions to the sediment-bound organic matter degrading salmonid spawning gravels in a lowland river, southern England.

The ingress of particulate material into freshwater spawning substrates is thought to be contributing to the declining success of salmonids reported over recent years for many rivers. Accordingly, the need for reliable information on the key sources of the sediment problem has progressed up the management agenda. Whilst previous work has focussed on apportioning the sources of minerogenic fine sediment degrading spawning habitats, there remains a need to develop procedures for generating corresponding information for the potentially harmful sediment-bound organic matter that represents an overlooked component of interstitial sediment. A source tracing procedure based on composite signatures combining bulk stable (13)C and (15)N isotope values with organic molecular structures detected using near infrared (NIR) reflectance spectroscopy was therefore used to assess the primary sources of sediment-bound organic matter sampled from artificial spawning redds. Composite signatures were selected using a combination of the Kruskal-Wallis H-test, principal component analysis and GA-driven discriminant function analysis. Interstitial sediment samples were collected using time-integrating basket traps which were inserted at the start of the salmonid spawning season and extracted in conjunction with critical phases of fish development (eyeing, hatch, emergence, late spawning). Over the duration of these four basket extractions, the overall relative frequency-weighted average median (±95% confidence limits) source contributions to the interstitial sediment-bound organic matter were estimated to be in the order: instream decaying vegetation (39±<1%; full range 0-77%); damaged road verges (28±<1%; full range 0-77%); septic tanks (22±<1%; full range 0-50%), and; farm yard manures/slurries (11±<1%; full range 0-61%). The reported procedure provides a promising basis for understanding the key sources of interstitial sediment-bound organic matter and can be applied alongside apportionment for the minerogenic component of fine-grained sediment ingressing the benthos. The findings suggest that human septic waste contributes to the interstitial fines ingressing salmonid spawning habitat in the study area.

First Report of Impatiens Downy Mildew Caused by Plasmopara obducens in Kentucky.

Impatiens downy mildew (Plasmopara obducens (J. Schröt.) J. Schröt. (syn Peronospora obducens) was first reported in the United States in 2004, but widespread outbreaks were observed throughout North America in 2011 (5). In June 2012, symptoms, including severe defoliation while plants retained upright stems, were observed on approximately 100 landscape impatiens (Impatiens walleriana Hook.f.) in Franklin County in central Kentucky. All plants in the landscape were affected. Plants were primarily defoliated and remaining leaves were stunted, mottled, and chlorotic with edges curled downward; no flowers were present. Under examination with a dissecting microscope, white downy fungal growth was observed. Closer examination confirmed that the growth consisted of colorless sporangiophores that were mainly unbranched, straight, and rigid (1,3). Sporangiophores consisted of apical branches attached at right angles to main axes, ranging from 67.2 to 89.9 µm long (1). Sporangia were ovoid and hyaline, measuring 11.2 to 13.3 µm × 8.2 to 10.7 µm (3). No oospores were observed. Pathogenicity tests were performed by inoculating 20 to 40 leaves on three plants each of the cvs. Dazzler and Super Elfin with suspensions of 1 × 105 sporangiophores per ml in sterile distilled water. Sporangia were obtained by washing infected leaves with sterile distilled water, and inoculations were completed by spraying leaves until runoff. Plants sprayed with sterile water served as controls. Plants were covered with black plastic bags for 48 h and then maintained under fluorescent lights for 10 days at room temperature (22 to 25°C). Sporangiophores were recovered from inoculated plants after 10 days, and morphology matched original inoculum; symptoms included chlorotic, downward curling leaves with sporulation on the undersides. Non-inoculated plants did not develop symptoms after 21 days. Molecular identification of the pathogen was conducted using three leaves from one plant from each cultivar. PCR was conducted by amplifying the large ribosomal subunit DNA using primers NL-1 and NL-4 (2). Amplicons of 762 to 691 bp were produced from diseased plant tissue that contained visible sporangiophores, and the bands were extracted from the gel and purified. Sequence results confirmed 100% similarity to accessions from Florida (GenBank Accession No. JX217746.1) and Ohio (JX142134.1) and 99% similarity to amplicons reported from Serbia (HQ246451.1) and UK (AY587558.1). This is believed to be the first report of downy mildew infecting impatiens in Kentucky. References: (1) O. Constantinescu. Mycologia 83:473, 1991. (2) W. Maier et al. Can. J. Bot 81:12, 2003. (3) P. A. Saccardo. Syllogue Fungorum 7:242, 1888. (4) S. N. Wegulo et al. Plant Dis. 88:909, 2004.

Flow cytometric immunobead assay for fast and easy detection of PML-RARA fusion proteins for the diagnosis of acute promyelocytic leukemia.

The PML-RARA fusion protein is found in approximately 97% of patients with acute promyelocytic leukemia (APL). APL can be associated with life-threatening bleeding complications when undiagnosed and not treated expeditiously. The PML-RARA fusion protein arrests maturation of myeloid cells at the promyelocytic stage, leading to the accumulation of neoplastic promyelocytes. Complete remission can be obtained by treatment with all-trans-retinoic acid (ATRA) in combination with chemotherapy. Diagnosis of APL is based on the detection of t(15;17) by karyotyping, fluorescence in situ hybridization or PCR. These techniques are laborious and demand specialized laboratories. We developed a fast (performed within 4-5 h) and sensitive (detection of at least 10% malignant cells in normal background) flow cytometric immunobead assay for the detection of PML-RARA fusion proteins in cell lysates using a bead-bound anti-RARA capture antibody and a phycoerythrin-conjugated anti-PML detection antibody. Testing of 163 newly diagnosed patients (including 46 APL cases) with the PML-RARA immunobead assay showed full concordance with the PML-RARA PCR results. As the applied antibodies recognize outer domains of the fusion protein, the assay appeared to work independently of the PML gene break point region. Importantly, the assay can be used in parallel with routine immunophenotyping for fast and easy diagnosis of APL.

Bio-monitoring for uranium using stream-side terrestrial plants and macrophytes.

This study evaluated the abilities of various plant species to act as bio-monitors for environmental uranium (U) contamination. Vegetation and soil samples were collected from a U processing facility. The water-way fed from facility storm and processing effluents was the focal sample site as it represented a primary U transport mechanism. Soils and sediments from areas exposed to contamination possessed U concentrations that averaged 630 mg U kg(-1). Aquatic mosses proved to be exceptional accumulators of U with dry weight (dw) concentrations measuring as high as 12,500 mg U kg(-1) (approximately 1% of the dw mass was attributable to U). The macrophytes (Phragmites communis, Scripus fontinalis and Sagittaria latifolia) were also effective accumulators of U. In general, plant roots possessed higher concentrations of U than associated upper portions of plants. For terrestrial plants, the roots of Impatiens capensis had the highest observed levels of U accumulation (1030 mg kg(-1)), followed by the roots of Cyperus esculentus and Solidago speciosa. The concentration ratio (CR) characterized dry weight (dw) vegetative U levels relative to that in associated dw soil. The plant species that accumulated U at levels in excess of that found in the soil were: P. communis root (CR, 17.4), I. capensis root (CR, 3.1) and S. fontinalis whole plant (CR, 1.4). Seven of the highest ten CR values were found in the roots. Correlations with concentrations of other metals with U were performed, which revealed that U concentrations in the plant were strongly correlated with nickel (Ni) concentrations (correlation: 0.992; r-squared: 0.984). Uranium in plant tissue was also strongly correlated with strontium (Sr) (correlation: 0.948; r-squared: 0.899). Strontium is chemically and physically similar to calcium (Ca) and magnesium (Mg), which were also positively-correlated with U. The correlation with U and these plant nutrient minerals, including iron (Fe), suggests that active uptake mechanisms may influence plant U accumulation.

Report from the 13th annual Western canadian gastrointestinal cancer consensus conference; calgary, alberta; september 8-10, 2011.

The 13th annual Western Canadian Gastrointestinal Cancer Consensus Conference was held in Calgary, Alberta, September 8-10, 2011. Health care professionals involved in the care of patients with gastrointestinal cancers participated in presentation and discussion sessions for the purposes of developing the recommendations presented here. This consensus statement addresses current issues in the management neuroendocrine tumours and locally advanced pancreatic cancer.

Gross and net rates of nitrogen mineralisation in soil amended with composted olive mill pomace.

Olive mill pomace is the major waste product in the olive oil industry and composting these by-products for the purpose of recycling nutrients and organic matter is a sound environmental strategy. Yet little is known about the quantity and timing of nitrogen (N) release from composted olive mill pomace. This paper assesses both gross (using the (15)N dilution technique) and net (aerobic incubation) nitrogen (N) mineralisation and N(2)O emissions of soil amended with seven commercially available composts of olive mill pomace (COMP). All are currently produced in Andalusia and differ in the proportions of raw materials co-composted with the pomace. The absence of significant differences in net N or gross mineralisation and nitrification in COMP-amended soil compared with a control, except for COMP combined with poultry manure, highlighted the recalcitrant nature of the COMP-N. Applications of COMP are hence unlikely to supply available N in available forms, at least in the short-term. Furthermore, N(2)O emissions from COMP-amended soil were negligible and, therefore, applications in the field should not result in increased N loss through denitrification.

High rates of nitrogen cycling in volcanic soils from Chilean grasslands.

There are over one million hectares of pasture in Chile, and 80% and 50% of the country's milk and meat comes from 72% of this area, situated in the lake region of southern Chile. The soils are volcanic and a major characteristic is that they have very high organic matter (OM) contents with the potential to support plant growth with only moderate levels of added nitrogen (N). To understand better the potential fertility of these soils in order to maximise production and minimise losses of N, we undertook studies using the stable isotope of N ((15)N) to resolve the rates of the main internal N cycling processes in three soils representing the two main volcanic soil types: Osorno and Chiloé (Andisol) and Cudico (Ultisol). We also assessed the longer-term potential of these soils to sustain N release using anaerobic incubation. Gross rates (µg N g(-1) day(-1)) of mineralisation were 27.9, 27.1 and 15.5 and rates of immobilisation were 5.9, 12.0 and 6.3 for Osorno, Chiloé and Cudico, respectively, implying high rates of net mineralisation in these soils. This was confirmed by anaerobic incubation which gave potential seasonal net mineralisation indices of 1225, 1059 and 450 kg N ha(-1) in the top 10 cm soil layers of the three soils. However, plant production may still benefit from added N, as the release of N from organic sources may not be closely synchronised with crop demand. The low rates of nitrification that we found with these acidic soils suggest that the more mobile N (viz. nitrate-N) would be in limited supply and plants would have to compete for the less mobile ammonium-N with the soil microbial biomass. Nitrogen was mineralised in appreciable amounts even down to 60 cm depth, so that leaching could become significant, particularly if the soils were limed, which could enhance nitrification and N mobility through the soil profile.