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BACKGROUND: Whole breast irradiation (WBI) after conservative surgery for ductal carcinoma in situ (DCIS) reduces local recurrence. We investigated whether a tumour bed boost after WBI improved outcomes, and examined radiation dose fractionation sensitivity for non-low-risk DCIS.METHODS: The study was an international, randomised, unmasked, phase 3 trial involving 136 participating centres of six clinical trials organisations in 11 countries (Australia, New Zealand, Singapore, Canada, the Netherlands, Belgium, France, Switzerland, Italy, Ireland, and the UK). Eligible patients were women aged 18 years or older with unilateral, histologically proven, non-low-risk DCIS treated by breast-conserving surgery with at least 1 mm of clear radial resection margins. They were assigned to one of four groups (1:1:1:1) of no tumour bed boost versus boost after conventional versus hypofractionated WBI, or randomly assigned to one of two groups (1:1) of no boost versus boost after each centre prespecified conventional or hypofractionated WBI. The conventional WBI used was 50 Gy in 25 fractions, and hypofractionated WBI was 42·5 Gy in 16 fractions. A boost dose of 16 Gy in eight fractions, if allocated, was delivered after WBI. Patients and clinicians were not masked to treatment allocation. The primary endpoint was time to local recurrence. This trial is registered with ClinicalTrials.gov (NCT00470236).FINDINGS: Between June 25, 2007, and June 30, 2014, 1608 patients were randomly assigned to have no boost (805 patients) or boost (803 patients). Conventional WBI was given to 831 patients, and hypofractionated WBI was given to 777 patients. Median follow-up was 6·6 years. The 5-year free-from-local-recurrence rates were 92·7% (95% CI 90·6-94·4%) in the no-boost group and 97·1% (95·6-98·1%) in the boost group (hazard ratio 0·47; 0·31-0·72; pINTERPRETATION: In patients with resected non-low-risk DCIS, a tumour bed boost after WBI reduced local recurrence with an increase in grade 2 or greater toxicity. The results provide the first randomised trial data to support the use of boost radiation after postoperative WBI in these patients to improve local control. The international scale of the study supports the generalisability of the results.FUNDING: National Health and Medical Research Council of Australia, Susan G Komen for the Cure, Breast Cancer Now, OncoSuisse, Dutch Cancer Society, Canadian Cancer Trials Group.

The main barrier to fast charging of Li-ion batteries at low temperatures is the risk of short-circuiting due to lithium plating. In-situ detection of Li plating is highly sought after in order to develop fast charging strategies that avoid plating. It is widely believed that Li plating after a single fast charge can be detected and quantified by using a minimum in the differential voltage (DV) signal during the subsequent discharge, which indicates how much lithium has been stripped. In this work, a pseudo-2D physics-based model is used to investigate the effect on Li plating and stripping of concentration-dependent diffusion coefficients in the active electrode materials. A new modelling protocol is also proposed, in order to distinguish the effects of fast charging, slow charging and Li plating/stripping. The model predicts that the DV minimum associated with Li stripping is in fact a shifted and more abrupt version of a minimum caused by the stage II-stage III transition in the graphite negative electrode. Therefore, the minimum cannot be used to quantify stripping. Using concentration-dependent diffusion coefficients yields qualitatively different results to previous work. This knowledge casts doubt on the utility of DV analysis for detecting Li plating.

Fast charging of batteries is currently limited, particularly at low temperatures, due to difficulties in understanding lithium plating. Accurate, online quantification of lithium plating increases safety, enables charging at speeds closer to the electrochemical limit and accelerates charge profile development. This work uses different cell cooling strategies to expose how voltage plateaus arising from cell self-heating and concentration gradients during fast charging can falsely indicate plating, contrary to prevalent current assumptions. A solution is provided using Differential Voltage (DV) analysis, which confirms that lithium stripping is observable. However, scanning electron microscopy and energy-dispersive X-ray analysis are used to demonstrate the inability of the plateau technique to detect plating under certain conditions. The work highlights error in conventional plating quantification that leads to the dangerous underestimation of plated amounts. A novel method of using voltage plateau end-point gradients is proposed to extend the sensitivity of the technique, enabling measurement of lower levels of lithium stripping and plating. The results are especially relevant to automotive OEMs and engineers wishing to expand their online and offline tools for fast charging algorithm development, charge management and state-of-health diagnostics.

Increased driving range and enhanced fast charging capabilities are two immediate goals of transport electrification. However, these are of competing nature, leading to increased energy and power demand respectively from the on-board battery pack. By fine-tuning the number of layers versus active electrode material of a lithium ion pouch cell, tailored designs targeting either of these goals can be obtained. Achieving this trade-off through iterative empirical testing of layer choices is expensive and often produces sub-optimal designs. This paper presents a model-based methodology for determining the optimal number of layers, maximising usable energy whilst satisfying specific acceleration and fast charging targets. The proposed methodology accounts for the critical need to avoid lithium plating during fast charging and searches for the optimal layer configuration considering a range of thermal conditions. A numerical implementation of a cell model using a hybrid finite volume-spectral scheme is presented, wherein the model equations are suitably reformulated to directly accept power inputs, facilitating rapid and accurate searching of the layer design space. Electrode materials exhibiting high solid phase diffusion rates are highlighted as being equally as important for extended range as the development of new materials with higher inherent capacity. The proposed methodology is demonstrated for the common module design of a battery pack in a plug-in hybrid vehicle, thereby illustrating how the cost of derivative vehicle models can be reduced. To facilitate model based layer optimisation, the open-source toolbox, BOLD (Battery Optimal Layer Design) is provided.

Purpose: To investigate person, cancer and treatment determinants of immediate breast reconstruction (IBR) in Australia. Methods: Bi-variable and multi-variable analyses of the Quality Audit database. Results: Of 12,707 invasive cancers treated by mastectomy circa 1998-2010, 8% had IBR. This proportion increased over time and reduced from 29% in women below 30 years to approximately 1% in those aged 70 years or more. Multiple regression indicated that other IBR predictors included: high socio-economic status; private health insurance; being asymptomatic; a metropolitan rather than inner regional treatment centre; higher surgeon case load; small tumour size; negative nodal status, positive progesterone receptor status; more cancer foci; multiple affected breast quadrants; synchronous bilateral cancer; not having neo-adjuvant chemotherapy, adjuvant radiotherapy or adjuvant hormone therapy; and receiving ovarian ablation. Conclusions: Variations in access to specialty services and other possible causes of variations in IBR rates need further investigation. Refereed/Peer-reviewed

Background: The study aim was to determine whether age is an independent risk factor for survival from early invasive breast cancer in contemporary Australian clinical settings. Methods: The study included 31 493 breast cancers diagnosed in 19982005. Risk of death from breast cancer was compared by age, without and with adjustment for clinical risk factors, using Cox proportional hazard regression. Results: Risk of breast cancer death was elevated for cancers of larger size, higher grade, positive nodal status, oestrogen receptor negative status, vascular invasion and multiple foci. Ductal lesions presented a higher risk than other lesions. Adjusting for these factors, the relative risk of breast cancer death (95% confidence limits) was lower for 4049-year-olds at 0.80 (0.66, 0.96) than for the reference category under 40 years, but higher for 7079-year-olds at 1.64 (1.36, 1.98) and women aged 80 years or more at 2.19 (1.79, 2.69). The risk for 5069-year-olds and women under 40 years was similar. Risk-factor adjustment reduced the difference in risk between the reference category under 40 years and 4049-year-olds, largely eliminated the lower relative risk for 5069-year-olds, and increased the relative risks for women aged 7079 years and older. Discussion: Survivals in women under 40 and over 70 years of age are poorer than for 4069-year-olds. Research is needed into the best treatment modalities for younger women and older women with co-morbidity.

At the turn of the millennium, approximately 34% of the Earth’s ice-free land surface was occupied by crops and pasture [1]. Our land currently feeds over 6 billion people, but by mid-century, it w...

The impact of forest fires on a boreal lake ecosystem was investigated in a discontinuous paleolimnological study of Christina Lake, in the mixedwood subregion of the boreal forest in northern Alberta (Canada). Diatom assemblages were examined below, within, and above charcoal-rich horizons in a sediment core, which represent local fire events. The total diatom concentration as well as the benthic to planktonic taxa ratio increased during charcoal peaks, but no detectable impact on taxa richness was observed. Diatom assemblage responses to fires generally lasted less than 5 years. Inter-taxa competition appears to be a major factor determining diatom assemblages in Christina Lake.

A high-resolution fen peat record and 79 basal peat dates from paludified peatlands in continental western Canada provide evidence for cyclic change in moisture conditions and in peat carbon accumulation. The ash-free bulk density, a proxy for degree of peat decomposition and thus moisture conditions, shows periodicities at both millennial (from 1500 to 2190 yr, with a mean of 1785 yr) and century scales (386 yr and 667 yr). Wet periods of 200–600 yr in duration, especially at ~6900, 5500 and 4000 cal. BP, correlate with rapid peat accumulation, new peatland initiation and declines in the rate of increase of atmospheric CO2 concentrations. The wet periods in western North America are coeval with warm periods in the North Atlantic, a phasing relationship that has been documented in other published palaeorecords for the glacial period and late Holocene, probably in response to variations in solar activity. These results indicate a strong connection between climate and the global carbon cycle at the millennial scale, mediated in part by peatland dynamics. This is the first demonstration that peatland carbon sequestration rates are highly sensitive even to minor climatic fluctuations, which are too small to produce detectable changes in major species in the peatland. That global atmospheric CO2 concentrations have in the past responded to these changes in peatland dynamics implies a strong potential for peatlands to be a major player in affecting future global change.

Assessing carbon sink–source relationships in peatlands must be based on the understanding of processes responsible for long-term carbon accumulation patterns. In contrast with ombrogeneous bogs, however, the processes in geogeneous fens are poorly understood. Here, we present high-resolution Holocene peat accumulation and macrofossil data from a rich fen (Upper Pinto Fen (UPF)) in west-central Alberta, Canada. The ~8000-year chronology of a 397 cm peat core was controlled by 20 accelerator mass spectrometry14C dates. The paludified peatland initially consisted of diverse brown moss species and some Larix trees but was dominated by Scorpidium scorpioides from 6500 to 1300 calibrated years BP. The last 1300 years are characterized by the reappearance of Larix together with abundant woody materials and Cyperaceae, culminating in a sharp increase in Tomenthypnum nitens in the last several decades. During the Scorpidium-dominated period, the peat accumulation pattern derived from 1514C dates and 260 bulk density measurements indicates declining mass accumulation rates over time (i.e., convex age–depth curve), in contrast with the standard bog growth model (i.e., concave curve). The analysis of the UPF data using an extended model incorporating variable peat addition rates (PAR) to the catotelm suggests a unidirectional sevenfold decrease in PAR from 191.8 to 26.0 g dry mass·m–2·year–1during the ~5000-year "convex period". Decreasing vegetation production and (or) increasing acrotelm decomposition could have produced the convex pattern. Decreasing PAR might be owing to autogenically induced changes in local hydrology and nutrient availability, which are pronounced in the moisture-limited climate of the region and in peatlands that have a strong groundwater influence. The convex-pattern model, explicit to the height-induced long-term drying hypothesis, has important implications for building simulation models and for projecting future carbon dynamics of peatlands. Prior to recent human disturbance, the UPF site has a time-weighted mean carbon accumulation rate of 31.1 g C·m–2·year–1, ranging from 7.2 to 182.5 g C·m–2·year–1during the last 8000 years. This large variation results from the gradual decline of long-term accumulation and short-term climate-induced accumulation "pulses". The results imply that in the absence of climatic change, peatlands with a convex accumulation pattern will reach their growth limit sooner and that their carbon sequestration capacity will decline faster than would be expected given the concave-pattern model.Key words: carbon dynamics, moisture and nutrient availability, macrofossils, peatland model, brown moss Scorpidium scorpioides.

Rocky outcrops represent about 30% of the boreal forest of Abitibi, Quebec, Canada. Although these outcrops have similar edaphic and climatic conditions, their vegetation can vary. Some are compose...

The Quality Audit (BQA) of Breast Surgeons of Australia and New Zealand includes a broad range of data and is the largest New Zealand (NZ) breast cancer (BC) database outside the NZ Cancer Registry. We used BQA data to compare BC survival by ethnicity, deprivation, remoteness, clinical characteristic and case load.BQA and death data were linked using the National Health Index. Disease-specific survival for invasive cases was benchmarked against Australian BQA data and NZ population-based survivals. Validity was explored by comparison with expected survival by risk factor.Compared with 93% for Australian audit cases, 5-year survival was 90% for NZ audit cases overall, 87% for Maori, 84% for Pacific and 91% for other.BC survival in NZ appears lower than in Australia, with inequities by ethnicity. Differences may be due to access, timeliness and quality of health services, patient risk profiles, BQA coverage and death-record methodology.

The production and decomposition of organic matter are major processes determining peat accumulation dynamics, both of which vary over different time scales. Here we evaluate three types of experimental and observational data related to peatlands, which are from litter, oxic (acrotelm) peat, and anoxic (catotelm) peat. The 210 Pb-dated peat-core profiles for the last 100–200 years are used to understand the oxic decomposition processes; 14 C-dated peat profiles for the last several millennia are used for understanding anoxic decomposition processes. Analysis of data from litter-bag experiments suggests that a significant portion of the litter is lost in the first few years owing primarily to rapid initial decomposition processes, including movement/leaching of soluble materials. This is also confirmed indirectly by 210 Pb-dated peat-core data. Several records of acrotelm peat show similar estimated litter-addition (26537.3 g m −2 year − 1 ) and decay rates (0.0170.0047 year − 1 ), despite the climatic difference among study areas. The litter-addition rate of 265 g m − 2 year − 1 is at most about half of measured net primary production. Warmer climate causes higher production but also higher decomposition. The balance of production and decay processes in the litter and acrotelm determines the peat addition rate to the catotelm, where long-term peat accumulation occurs. Our sensitivity analysis shows that change in the peat-addition rate would affect both young and old peat; in contrast, a change in the decay rate has more influence on old peat. We therefore hypothesize that the wiggles often seen in peat age–depth profiles are caused by changes in peat addition rates, which are determined by climatically sensitive processes including photosynthesis and acrotelm decomposition. Evaluating these litter and peat-core data provides insights useful to the design and implementation of a peatland dynamics simulation model. © 2001 Elsevier Science B.V. All rights reserved.

This article reviews the existing conceptual and simulation models for peatlands and develops a model framework for simulating peatland dynamics in boreal regions. Clymo's peat bog growth model has been used as the conceptual foundation in published simulation models, but in these models the structural and functional layers of litter, acrotelm and catotelm are not dynamically integrated. Organic-matter decomposition processes in these layers operate at different rates over various time scales. The processes in more active litter and acrotelm layers largely pre-determine the net peat accumulation in the catotelm. On the basis of evaluating litter and peat-core data, we propose a model design that connects different layers through changing water-table depth, driven by effective moisture. The model framework includes single and double negative exponential decay functions that together produce net peat accumulation or degradation and hence carbon balance. The model is designed to be generic in structure, but can be validated using estimated parameters and observed peat accumulation data for continental western Canada. The objectives of this model exercise are (1) to understand the interactions of different biological and environmental factors in boreal peatlands, and (2) to realistically simulate peat accumulation and decay over the last several millennia using proxy paleoclimate data as drivers and peat profiles for validation.

General circulation model simulations suggest the Earth's climate will be 1–3.5°C warmer by AD 2100. This will influence disturbances such as forest fires, which are important to circumpolar boreal forest dynamics and, hence, the global carbon cycle. Many suggest climate warming will cause increased fire activity and area burned. Here, we use the Canadian Forest Fire Weather Index to simulate future forest fire danger, showing the expected increase in most of Canada but with significant regional variability including a decrease in much of eastern Canada. These results are in general agreement with paleoecological data and general circulation model results from the 6000 calendar years BP interval, which was a time of a warmer climate that may be an analogue for a future climate.

Two high resolution palaeofire signals were extracted from the annually-laminated sediment of Christina Lake in the boreal forest of Alberta, Canada. A charcoal curve focusing on large charcoal fragments (>125 μm) was extracted by the sieving method described by Whitlock and Millspaugh. A carbon curve which includes all size fractions of charcoal was extracted by a method modified from Winkler's chemical assay method. Modifications included increasing the duration of nitric acid treatment to 2 h and using a total carbon analyser (TCA) rather than standard loss on ignition. These adjustments resulted in a carbon curve which is unaffected by clay water losses and subtle changes in sedimentology which were problematic in the original gravimetric technique. The sensitivity of the TCA allowed subtle shifts in carbon (i.e. charcoal) abundance to be detected in lake sediments with low levels of charcoal. When compared with the known fire history near the lake since 1900, the sieved charcoal curve was most responsive to fires known to burn near the shore of the lake and less responsive to fires burning elsewhere in the watershed. The TCA carbon curve was somewhat more sensitive than the sieved charcoal curve for detecting fires in the drainage basin which did not burn to the lake edge. The TCA carbon curve was strongly correlated with sediment influx, suggesting stream inputs of charcoal are the dominant influence on this signal. The peak in response of the TCA curve to known fire events was sometimes lagged by several years, suggesting that it can take several seasons for the bulk of stream-transported charcoal to make its way from the watershed to its final deposition site in the lake. Very large fires burning just outside the drainage basin of the lake were not detected by either method, suggesting that both of the methods used are sensitive only to fires burning in the watershed and that long-distance aerially dispersed charcoal is insignificant at this site.

A transect of three shallow ponds across the Aspen Parkland/Boreal Forest transition in Elk Island National Park, Alberta, Canada, shows changes in late Holocene vegetation and disturbance dynamics, and consequent carbon storage, in response to climate change and to recent anthropogenesis. Pollen and charcoal analyses reveal unexpected changes in fire regime. Although there is the expected decline in fire activity during the historic period, presumed due to agricultural clearance around the park, there is also a prehistoric fluctuation in fire regime at one of the sites. Pollen evidence suggests that the fluctuations in fire regime may be due to changes in hydrology. Declining groundwater levels during the Medieval Warm Period allowed the replacement of substantial areas of shrub birch (Betula glandulosa) with the less fire-prone aspen (Populus tremuloides) causing a decline in fire frequency and/or severity, while increasing carbon storage on the landscape. This is counter to the intuitive increase in fire activity with warmer and drier climate. Canadian national parks are currently managed under a ‘natural processes and conditions’ paradigm; the changes in conditions and consequent changes in processes evident due to the relatively minor climatic fluctuations of the Little Ice Age and Medieval Warm Period shown here suggest a need to revisit this paradigm in consideration of future anthropogenic climate change.

A natural ∼1450-yr global Holocene climate periodicity underlies a portion of the present global warming trend. Calibrated basal radiocarbon dates from 71 paludified peatlands across the western interior of Canada demonstrate that this periodicity regulated western Canadian peatland initiation. Peatlands, the largest terrestrial carbon pool, and their carbon-budgets are sensitive to hydrological fluctuations. The global atmospheric carbon-budget experienced corresponding fluctuations, as recorded in the Holocene atmospheric CO2 record from Taylor Dome, Antarctica. While the climate changes following this ∼1450-yr periodicity were sufficient to affect the global carbon-budget, the resultant atmospheric CO2 fluctuations did not cause a runaway climate–CO2 feedback loop. This demonstrates that global carbon-budgets are sensitive to small climatic fluctuations; thus international agreements on greenhouse gasses need to take into account the natural carbon-budget imbalance of regions with large climatically sensitive carbon pools.

This paper reports on a high-resolution, multi-proxy, late-Holocene study from a lake in the Aspen Parkland of southern Alberta, Canada. A sediment core spanning the last 4000+ yrs from Pine Lake was analyzed for charcoal, granulometry, grain roundness, tephra content, geochemistry, mineralogy and pollen. This multi-proxy record indicates: (1) increasing anoxia causing a shift in S deposition from gypsum to pyrite due to increasing moisture availability in the late Holocene; (2) a decrease in Mg flux into the lake due to the development of the aspen forest, which reduced water flow through the Mg-rich shallow sand aquifer; the aspen forest expansion was in turn induced by the extirpation of plains bison prior to settlement; and (3) a change in the upland fire regime from frequent low-biomass grass fires to less frequent but higher biomass under-story fires, also as a result of the expansion of the aspen forest. Not only are the different proxies sensitive to different rates and magnitudes of change, they also show different sensitivities to different types of hydrological change: the mineralogy and geochemistry are sensitive to changes in water level and redox potential, and to changes in the relative strengths of the aquifers feeding the lake, while the granulometry is sensitive to total hydrological balance. Thus, apparently contradictory proxy results should be viewed as complementary.

This paper reports a first estimate of the Holocene lake sediment carbon pool in Alberta, Canada. The organic matter content of lake sediment does not appear to depend strongly on lake size or other limnological parameters, allowing a simple first estimate in which we assume all Alberta lake sediment to have the same organic matter content. Alberta lake sediments sequester about 15 g C m-2 yr-1, for a provincial total of 0.23 Tg C yr-1, or 2.3 Pg C over the Holocene. Alberta lakes may represent as much as 1/1700 of total global, annual permanent carbon sequestration.

In this study we compare seasonal pollen and spore assemblages in river waters from the Mississippi River at Vicksburg, Mississippi to those downstream at Belle Chasse, Louisiana and in a distributary, the Atchafalaya River at Morgan City, Louisiana. Assemblages of pollen in waters at Vicksburg and Belle Chasse are similar to each other, but distinctively different from those in the Atchafalaya River. Local pollen inputs are more important in the anastomosing Atchafalaya River channel, as compared to the meandering main stem Mississippi channel which discharges through the bird-foot delta. Riverine pollen and spore assemblages are also compared to those of surface sediments from the Louisiana continental shelf in the vicinity of the Mississippi River plume. In this area the primary source of marine pollen and spore assemblages appears to be the discharge from the main stem Mississippi, with limited input from the Atchafalaya. Thus, pollen deposited in these coastal waters provides a record of vegetation in the Mississippi drainage basin, rather than local coastal areas. Pollen assemblages on the continental shelf vary with distance from the river source, but not in a systematic manner. The pattern is explained by biological controls on fine-particle deposition in marine waters, i.e., deposition of pollen in copepod fecal pellets. As copepod grazing is dependent upon phytoplankton production, pollen deposition from the river plume will be limited by high turbidities proximal to the river mouth. We hypothesize that in neritic environments, pollen is preferentially deposited in areas corresponding to high phytoplankton production, which are characterized by reduced turbidity and high nutrient availability.

Pollen assemblages are affected by a variety of processes between dehiscence and recovery. Here, two examples from western Canada illustrate two of the most important biases affecting pollen assemblages after production and initial dispersal. A site in Canada's Yukon Territory provides evidence of selective redeposition of penecontemporaneous pollen grains, which is detectable only through paired coring. A deposit on the floor of a kettle depression shows trends in the ratios of extra-local pollen types, which are opposed to the trends shown in a core taken from the slope of the same depression. This is explained as a trend to reduced mobility of saccate grains with time due to increased permeability of the substrate on the kettle slope. A study of the differential degradation of Populus pollen illustrates the complexities of pollen preservation. Populus pollen is generally recognized as more susceptible to corrosion than are most other pollen types. The poor preservation of this pollen type is attributed largely to its lack of harmomegathic adaptation and low sporopollenin content. This real susceptibility is compounded by the pollen grain's lack of distinctive surface ornamentation, inhibiting recognition of damaged grains. At least part of the general impression of poor preservation of Populus pollen may be due to a recent increase in the abundance of Populus on the landscape in western Canada. Early studies in this region may have sampled sediments from before the increase in Populus, and compared their pollen spectra with post-Populus increase vegetation.

Projected future climates, such as increasing temperature, increasing atmospheric CO2, altered precipitation patterns and increases in the frequency of climatic extremes, are likely to alter the performance and distribution of crops as well as influence the entry, establishment and spread of invasive weeds, pests and pathogens that affect them. Climate change will require a revision of current biosecurity practices, such as preparedness, prevention, containment policies, surveillance response, incursion management and trade and market access issues.

The National Breast Cancer Audit collects data on the care of early breast cancer patients in Australia and New Zealand. An overview of invasive breast cancer in New Zealand is presented with emphasis on comparing the screened population with symptomatic referrals.All New Zealand data in the National Breast Cancer Audit with a diagnosis date of 2008 have been included in the report. Data was analysed with an aim to compare the presenting features and management of screen detected invasive cancer with symptomatic referrals in New Zealand.There were 2371 cases of breast cancer, 52% of which were symptomatic referrals, 37% of which were BreastScreen Aotearoa referrals. Higher breast conservation rates were reported in the screening population. 3% of patients had involved margins after surgery. Almost two-thirds (62%) of BreastScreen patients underwent a sentinel node biopsy without further axillary surgery. 72% of screening patients and 86% of symptomatic patients who were high risk did not receive post mastectomy radiotherapy. A larger proportion of symptomatic patients received chemotherapy. Endocrine therapy was prescribed to 81% of hormone receptor positive patients.Patients with early invasive breast cancer in New Zealand were managed appropriately according to audit performance indicators and clinical guidelines. The numbers of high risk patients not receiving post mastectomy radiotherapy and the lack of endocrine treatment in some patients with hormone receptor positive tumours may warrant further investigation.

The study aim was to determine whether age is an independent risk factor for survival from early invasive breast cancer in contemporary Australian clinical settings. The study included 31 493 breast cancers diagnosed in 1998-2005. Risk of death from breast cancer was compared by age, without and with adjustment for clinical risk factors, using Cox proportional hazard regression. Risk of breast cancer death was elevated for cancers of larger size, higher grade, positive nodal status, oestrogen receptor negative status, vascular invasion and multiple foci. Ductal lesions presented a higher risk than other lesions. Adjusting for these factors, the relative risk of breast cancer death (95% confidence limits) was lower for 40-49-year-olds at 0.80 (0.66, 0.96) than for the reference category under 40 years, but higher for 70-79-year-olds at 1.64 (1.36, 1.98) and women aged 80 years or more at 2.19 (1.79, 2.69). The risk for 50-69-year-olds and women under 40 years was similar. Risk-factor adjustment reduced the difference in risk between the reference category under 40 years and 40-49-year-olds, largely eliminated the lower relative risk for 50-69-year-olds, and increased the relative risks for women aged 70-79 years and older. Survivals in women under 40 and over 70 years of age are poorer than for 40-69-year-olds. Research is needed into the best treatment modalities for younger women and older women with co-morbidity.

Experimental degradation of pollen by repeated wet‐dry cycles in saline and desalinated sediments show differences in preservation between taxa and between salinity environments. In desalinated sediment, from which the salts were removed artificially, pollen is rapidly degraded, with a significant net loss of pollen after ten wet‐dry cycles. Picea pollen, which remains identifiable even when heavily damaged, suffers greater breakage in desalinated sediments. Artemisia pollen is rapidly rendered unidentifiable by degradation of the sculptural elements in both saline and desalinated sediments. In comparison to desalinated sediments, saline sediments appear to contain less damaged pollen. Growing salt crystals may envelop the pollen grains and stabilize them against mechanical breakage otherwise incurred by flexing of the pollen wall during desiccation. Caution should be exercised when analyzing sediments subject to wet‐dry cycles, and laboratory procedures modified if necessary to avoid desiccation...

Thirty water samples from a cross‐section of the Atchafalaya River taken at Morgan City, Louisiana in June 1991, have pollen concentrations on the order of 3500 grains/l. There are only rare grains attributable exclusively to long‐distance transport from the northern United States, and the assemblage is dominated by species common in the local area. However, the condition of much of the pollen suggests that it is largely reworked. Point‐velocities obtained for each sample vary from 0.58 m/sec to 1.3 m/sec. There are only minor variations among pollen assemblages, with differences in velocity and position (i.e., water surface or deeper in the water column) having only minimal influence on the pollen distribution. It is likely the differences that do exist reflect unmixed waters of drainages which confluence immediately upstream of the sample site. Compared to 1987 data from the Mississippi River, the June pollen spectra of the Atchafalaya are enriched in the locally abundant Taxodiaceae‐Cupressace...

(1992). Service provision, programme development and its measurement. AIDS Care: Vol. 4, No. 4, pp. 460-463.

Many types of stratigraphic data (for example pollen, diatoms, bulk geochemistry) are presented conveniently in a depth/frequency diagram having several frequency curves on a common depth scale. CANPLOT is a FORTRAN-77 program for plotting such stratigraphic data on a PostScript output device. Several options are included, such as stratigraphically constrained cluster analysis of the data, and a variety of graphical enhancements for producing camera-ready figures.

The aortic valve has received much attention in the biomedical research community during recent years. As a critical part of the cardiovascular system, any alteration in its structure or in the surrounding area directly or because of pathologies would change the flow pattern of that region as a consequence. Numerous studies have been done and regardless of the approach, the aim of all these studies is the same: to understand the intricacies of the healthy aortic valve and, perhaps, to mimic it in the realm of prosthetics.Copyright © 2009 by ASME

Two simple experiments show that mechanical pollen damage is not caused by pollen‐clast collisions during transport, but that wet‐dry cycles may be very effective at degrading pollen. These experiments suggest that horizons of damaged pollen in subaqueous sediment more likely result from redeposition of pollen previously exposed to subaerial weathering, rather than from damage incurred during transport.

Cluster analysis of Ontario pollen stratigraphies demonstrates similar regional successions during the past 1000 years. Seven character states qualitatively describe the behaviour of the pollen percentage trends for each taxon: 0, absent; 1, present with no visible trend but high noise; 2, rising through time; 3, falling through time; 4, rise–fall; 5, fall–rise; and 6, stable through time. The three similarity indices (S) used were of the form S equals the number of characters in agreement divided by the number of informative characters. The three clustering techniques used are single linkage, complete linkage, and unpaired weighted geometric mean analysis. Single linkage and unpaired weighted geometric mean analysis showed a north–south division with all three indices; complete linkage showed only rare local groupings with all three indices. The division between the two clusters falls just south of Lake Nipissing. All successions indicate climatic cooling; the clusters reflect southward movement of the centres of species abundances, particularly white pine. The method identifies regions of similar vegetation dynamics. Key words: cluster analysis, forest dynamics, Holocene, Little Ice Age, Ontario, palynology.

The international community can learn much from the experiences of Africa in developing integrated AIDS management programs. While short term tactical interventions are important AIDS control in Africa and global AIDS control will not be solved through vaccine or treatment. The keynote address of the San Francisco Conference given by Eunice Kiereini of Kenya acknowledged the influence of the community as the chief determinant of change. Other papers emphasizes the need to involve community leaders in facilitating community awareness and the need to train community outreach counsellors to support AIDS patients and their families. Home care programs were discussed with the emphasis on community prevention through home care. Other papers presented by representatives of African nations offered important contributions to the understanding of human and organizational resource development to the study of behaviors identified with a high risk of spread of HIV and to the study of the distribution and mortality rates associated with HIV. Elizabeth Ngugi of Kenya in the summary session emphasized the importance of offering people choices and basing programs within the community. Africa has more experience in developing integrated AIDS management programs in mobilizing the community to prevent the spread of AIDS and in normalizing AIDS. Africa needs to continue its participation in international conferences and the world community needs to learn from the experiences of the African continent in dealing with AIDS.

GLOBAL climatic change may alter species' ranges as well as restructuring ecosystems1–3. Models simulating forest growth predict that the area covered by different forest types may be affected2, which may in turn further affect climate3. In the mixed forests of southern Ontario, pollen analyses have demonstrated that after AD 1400, Fagus (beech), the formerly dominant warmth-loving species, was replaced first by oak (Quercus) and subsequently by pine (Pinus strobus). Although these changes had been attributed to aboriginal forest clearance4–6, they have also been seen in areas unaffected by aboriginal farming, and are now thought to reflect Little Ice Age cooling7. Although modelling suggests that some forests may take several centuries to reach equilibrium after a climatic change8,9, a real forest showing this behaviour has not previously been identified. Here we model the Little Ice Age by a 2 °C decrease in mean annual temperature from AD 1200 to 1850, and show that the changes predicted by a forest simulator derived from FORET10match those seen in southern Ontario. These forests thus appear to have remained in disequilibrium with the prevailing climate for more than 650 years.

Many spherical microfossils have regularly pat­ terned surface features, the number of which can be useful for precise identification (Faegri and Iversen, 1989). These features may be pores, spines, verrucae, or other sculptural or structural elements. For example, the number of pores on a grain of chenopod pollen may be used to narrow the list of possible species (Faegri and Iversen, 1989). McAndrews and Swanson (1967) proposed a geo­ metrical model relating the number of pores on a periporate pollen grain to the ratio of the distance between the centres of pores (chord) and the diameter of the pollen grain. They also suggest that since the chord/diameter (Cj D) ratio is a function of the feature density,. this ratio may be used in place of feature number in identification keys. However, with the exception of their own paper, this plan has not been carried out in other keys. Their model, which can be applied to any spherical object with regularly patterned surface features, produced a set of equations, which culmi­ nates in the approximate number of pores. Christensen (1986) corrected McAndrews and Swanson's published equations, which contained a typographical error, and further simplified them. The basis of Christensen's method is nevertheless the same as McAndrews and Swanson's method, i.e. estimating the number of triangles with a specified length of side which can be placed on the surface of a sphere, and the results are very similar.

Studies of pollen source areas of closed-canopy sites are contradictory. Some authors found that closed-canopy sites mainly collect local pollen while others found more distant sources. This dichotomy might stem from the use of canopies of varying degrees of closure, and from variations in the pollen productivity of the local vegetation and the background pollen rain. Here, 30 islands were used to evaluate the pollen sources of closed-canopy sites. We compared pollen with the forest inventory in three quadrat sizes: 100, 400 m 2 and on the whole island. Regression analyses showed that most pollen of Picea spp., Pinus spp., and Betula spp. comes from within the 400 m 2 quadrat. Abies balsamea and Thuja occidentalis showed no relationship with vegetation in any of the quadrats considered, suggesting a more regional source. Insularity and island size are important factors influencing the pollen source area; correlations were stronger on islands located 1200 m from the nearest shore and on islands >50 ha. These results suggest that closed-canopy sites on islands may be useful in stand-level vegetation history reconstruction through pollen analysis, but that caution must be exercised in separating the local and regional signals.

The ecological role of fire in the modern boreal forest has been reviewed by several authors (Wright and Heinselman 1973; Wein and MacLean 1983; Johnson 1992, Payette 1992). Wildfire and climate are intimately linked (Swetnam 1993). Shorter-term weather patterns are clearly an important determinant of fire activity at daily-to-monthly time scales. At longer time scales of decades and centuries, Swetnam (1993) has shown that fire occurrence in Giant Sequoia groves was related to climate. However, other factors such as topography and fuel play a role in the fire regime. Fuel type, structure, moisture, accumulation, density, flammability, and continuity can affect the fire regime.1 An extreme example highlighting the role of fuel can be found in many deserts where fires should be frequent due to the hot and dry environment but are absent because there is no fuel. Therefore, climate controls fire directly through opportunities for ignition and spread but also through regulation of the accumulation and structure of fuel at decadal or greater time scales.

Airborne particulates can be carried over long distances, but for significant quantities of particulates larger than a few micrometres in diameter to be transported more than a few kilometres usually requires a means of injecting the material high into the atmosphere, such as a volcanic eruption, forest fire or desert windstorm. But an unusual event occurred in the Canadian Arctic last year, in which significant amounts of pine and spruce pollen (30-55 μm long) were transported roughly 3,000 km.

AIDS is a multi-disciplinary problem, but also a multi-disciplinary opportunity, given the capacity of individuals, groups and organizations to integrate talents and resources. The impact of AIDS in east, southern and central Africa is discussed in general terms to answer the question. “Why integrate?” Ways in which integration is expressed are discussed, including integration within the definition of AIDS management, integration within programs, and between team members, between the community and the hospital, and from field programs to Ministries of Health, donor organizations and the World Health Organization. Issues in integration at the field level, including management models, the concept of teams, and consensus on major goals, are discussed, and comment is made on the key integrative theme of families and communities.

Clark and Royall (1995) present a charcoal influx curve for Crawford Lake in southern Ontario and conclude that the Indians were responsible for a succession from beech to oak and pine throughout southern Ontario. We present an alternative hypothesis, that the 'Little Ice Age' caused the forest succession and that domestic fires and burning of stubble in agricultural fields were responsible for the charcoal record.

Fourier and nonlinear regression analysis of a 4000+ yr paleoclimate proxy record in western Canada shows strong periodicities of ∼1500 yr and several weaker century- to millenial-scale periodicities. In conjunction with the 23 708 yr Milankovitch periodicity, these produce a model of climate fluctuation through the postglacial consistent with recognized paleoclimatic fluctuations of the past 15 000 yr in the northern mid-latitudes. These results suggest that postglacial climatic anomalies such as the Little Ice Age and the Younger Dryas were at least in part periodic phenomena rather than the result of unique, aperiodic events. Projecting these periodicities into the future suggests that even in the absence of anthropogenic climate forcing, a natural warming trend will continue until ca. a.d. 2400.