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Treatment of wastewater generally results in elevated natural 15 N abundance (d 15 N) in the effluent and sludges. For example, high d 15 N values are found in treated sewage effluent, biosolids, and other wastes that are commonly applied to land. In contrast, N deficient coniferous forest soils usually have a low d 15 N. When wastes with high d 15 N values are applied to land, their distinctive d 15 N signature can potentially be used to trace the fate of waste-derived N in the ecosystem. In this paper, we provide an overview of the use of d 15 N in land application of wastes, including New Zealand case studies on tracing nitrogen in forest ecosystems. [ABSTRACT FROM AUTHOR]

Using stable N isotopes, the fate of effluent-derived N has been determined within a land based municipal effluent irrigation scheme. Over 900 metric tonnes (t) of effluent-derived N have been applied to 192 ha of production conifer forest near Rotorua (NZ) over the past 11 years. The effluent N has a natural isotopic signal, generated by the treatment process, allowing it to be traced into various components of the system. Using this isotopic signal, a realistic approximation of storage capacity of various components of the system has been generated, including a calculation of the contribution of effluent N exiting the catchment via stream flow. Forest storage accounts for 50% of the applied N with a considerable proportion of that immobilized in wood and soil. The wetland, although not intensively sampled, retains 115 t, (13%) of the applied N. Denitrification, including that occurring within the wetland, accounts for 23 t (3%). Nitrogen isotope data confirm that the rise in NO 3 concentrations is directly attributable to effluent N. Currently 88% of NO 3 -N in the stream is effluent-derived. Using current N isotope values for the stream and extrapolating over the discharge period, export of effluent N via the stream is estimated as 263 t (29%) of the applied N. Overall the forest and wetland ecosystem has intercepted or denitrified 65% of applied N, with 29% lost to the stream, and 50 t (5%) unaccounted for. The forest ecosystem is currently over-supplied with N and a number of management implications flows from these findings. In the long term the continued application of effluent N to the current irrigation area is not sustainable. [ABSTRACT FROM AUTHOR]

The atmospheric concentrations of HCI, HONO, HNO3, SO2and NH3 have been measured at an urban background site in Auckland, New Zealand in the summer and winter of 2003. Their median concentrations (pptv) were 31, 90, 34, 119 and 1,560 respectively in the summer and 12, 306, 37, 127 and 1,852 in the winter. Previous measurements of these gases in New Zealand are lacking. HONO experienced the most pronounced seasonal difference, having significantly higher wintertime concentrations, NH3 had only slightly higher concentrations in winter, however in contrast HCI demonstrated an opposite seasonal trend (significantly higher summertime concentrations), while HNO3 and SQ2 did not have any apparent seasonal variations. Although in the summer these gaseous species did not show significant differences in their atmospheric concentrations between weekdays and weekends, in the winter the atmospheric concentrations of HONO, HNO3, SO2 and NH3 were significantly higher on weekdays than on weekends. It is proposed that in the Auckland summer, vehicle emissions are the dominant source of HONO, HNO3, and NH3, but that most SO2 is produced from both vehicular and marine sources. However in winter it appears that all but HCI had major vehicle-related sources. It is also suggested that degassing of chloride from sea salts could be the major source of HCI at this site. [ABSTRACT FROM AUTHOR]

Aim: Colorectal cancer (CRC) is a common malignancy in New Zealand, and there is increasing pressure on investigative resources for diagnosis. The national direct access referral guidelines from the Ministry of Health (MoH) guide who should be referred for investigation, but their performance in detecting CRC and other significant diseases has not been reported previously. This paper describes the yield, by direct access criterion, of all referrals through the direct access pathway to the Canterbury District Health Board (CDHB) during 2018., Methods: First referrals received through the direct access colonoscopy/computed tomography colonography (CTC) pathway for 2018 were audited. Patients were assigned to symptom groups corresponding to the MoH direct access criteria, and demographic data were captured. Diagnostic outcomes were collected through analysis of all endoscopy, CT colonography and histology reports in the 18 months following referral for primary analysis, with further follow-up through to May 2021 to detect missed pathology., Results: Three thousand two hundred referrals were analysed, and 88.5% underwent colorectal investigation. 128 CRC were diagnosed, 176 advanced polyps, 49 cases of inflammatory bowel disease (IBD) and there were 56 other significant findings. The yield by category for the direct access criteria varied between 0-15.0%, and one urgent criterion had a CRC yield lower than two semi-urgent categories. For patients whose symptoms met at least one of the criteria, excluding those referred with suspected IBD, the combined CRC yield was 4.9%, compared with 1.8% in those who did not meet criteria. The sensitivity and specificity of the criteria for CRC (excluding IBD) was 90% and 23% respectively. There were no CRC detected during the extended follow-up period., Conclusion: In this referred population, the MoH direct access colonoscopy/CTC criteria varied significantly in their CRC yield, with an arbitrary distinction between urgent and semi-urgent categories. The low specificity of the criteria means the number needed to investigate to detect one CRC was one in 22. Improved diagnostic algorithms are urgently required to improve both the sensitivity and specificity, thereby more appropriately allocating finite resources to those patients who are most in need of investigation., Competing Interests: Nil., (© PMA.)

The study of coastal processes is critical for the protection and development of beach amenities, infrastructure, and properties. Many studies of beach evolution rely on data collected using remote sensing and show that beach evolution can be characterized by a finite number of "beach states". However, due to practical constraints, long-term data displaying all beach states are rare. Additionally, when the dataset is available, the accuracy of the classification is not entirely objective since it depends on the operator. To address this problem, we collected hourly coastal images and corresponding tidal data for more than 20 years (November 1998-August 2019). We classified the images into eight categories according to the classic beach state classification, defined as (1) reflective, (2) incident scaled bar, (3) non-rhythmic, attached bar, (4) attached rhythmic bar, (5) offshore rhythmic bar, (6) non-rhythmic, 3-D bar, (7) infragravity scaled 2-D bar, (8) dissipative. We developed a classification model based on convolutional neural networks (CNN). After image pre-processing with data enhancement, we compared different CNN models. The improved ResNext obtained the best and most stable classification with F1 -score of 90.41% and good generalization ability. The classification results of the whole dataset were transformed into time series data. MDLats algorithms were used to find frequent temporal patterns in morphology changes. Combining the pattern of coastal morphology change and the corresponding tidal data, we also analyzed the characteristics of beach morphology and the changes in morphodynamic states.

Treated biosolids have been applied to 750-ha of a Pinus radiata forest plantation on Rabbit Island near Nelson City in New Zealand since 1996. A long-term research trial was established in 1997 to investigate the effects of the biosolids applications on the receiving environment and tree growth. An analysis of the likely economic impact of biosolids application shows that biosolids application has been beneficial. Stem volume of the high treatment (biosolids applied at 600 kg N ha(-1) every three years) was 36% greater than the control treatment (no biosolids applied), and stem volume of the standard treatment (300 kg N ha(-1)) was 27% greater than the control treatment at age 18 years of age. Biosolids treatments have effectively transformed a low productivity forest site to a medium productivity site. Although this increased productivity has been accompanied by some negative influences on wood quality attributes with reduced wood stiffness, wood density, and larger branches, an economic analysis shows that the increased stem volume and greater average log diameter in the biosolids treatments outweighs these negative effects. The high and standard biosolids treatments are predicted to increase the net stumpage value of logs by 24% and 14% respectively at harvesting, providing a large positive impact on the forest owner's economic return.

Wintertime PM10 samples from two New Zealand cities (Christchurch and Auckland) have been characterized using gas chromatography - mass spectrometry for biomass burning tracers, hopanes, n-alkanes, fatty acids, n-alkanols and sugars. The aerosol samples of Christchurch, which were heavily influenced by residential wood and coal burning, showed substantially higher ambient concentrations for most of the organic compounds than those of Auckland, where major sources of aerosols were vehicular emissions and sea-salt. Mass ratios between the biomass burning tracers studied were found to be significantly different (e.g., beta-sitosterol to nssK+ ratios were more than three times higher in Christchurch than in Auckland), although levoglucosan to nssK+ ratios were similar at the both sites. We also estimated, for the first time using stereochemical configurations of hopanes, that 60% of fossil fuel emissions came from petroleum utilization with the remaining 40% being from coal burning in Christchurch. In contrast, contribution of coal burning was negligible in Auckland. Moreover, contributions of most biomass burning tracers to organic carbon (OC) were significantly higher in Christchurch than in Auckland. On the other hand, saccharides (excluding levoglucosan) and hopanes accounted for larger fractions of OC in Auckland. This study demonstrates that intensive wood and coal burning can significantly affect organic aerosol composition in an urban environment.

Using stable N isotopes, the fate of effluent-derived N has been determined within a land based municipal effluent irrigation scheme. Over 900 metric tonnes(t) of effluent-derived N have been applied to 192 ha of production conifer forest near Rotorua (NZ) over the past 11 years. The effluent N has a natural isotopic signal, generated by the treatment process, allowing it to be traced into various components of the system. Using this isotopic signal, a realistic approximation of storage capacity of various components of the system has been generated, including a calculation of the contribution of effluent N exiting the catchment via stream flow. Forest storage accounts for 50% of the applied N with a considerable proportion of that immobilized in wood and soil. The wetland, although not intensively sampled, retains 115 t, (13%) of the applied N. Denitrification, including that occurring within the wetland, accounts for 23 t (3%). Nitrogen isotope data confirm that the rise in NO3 concentrations is directly attributable to effluent N. Currently 88% of NO3-N in the stream is effluent-derived. Using current N isotope values for the stream and extrapolating over the discharge period, export of effluent N via the stream is estimated as 263 t (29%) of the applied N. Overall the forest and wetland ecosystem has intercepted or denitrified 65% of applied N, with 29% lost to the stream, and 50 t (5%) unaccounted for. The forest ecosystem is currently over-supplied with N and a number of management implications flows from these findings. In the long term the continued application of effluent N to the current irrigation area is not sustainable.

Objectives: To determine influenza vaccination coverage in 2001 in Australian adults aged > or = 40 years, assess awareness of and attitudes to influenza vaccine, factors associated with vaccination, and estimate uptake of free vaccine provided to those aged > or = 65 years., Methods: National computer-assisted telephone interview (CATI) survey in October/November 2001., Results: Interviews were completed with 5,266 people aged > or = 65 and 2,415 aged 40-64 years. Thirty per cent of selected households participated. Overall, 67% of respondents believed that the vaccine was somewhat to very effective in preventing influenza. Seventy-eight per cent of those aged > or = 65 years reported influenza vaccination; 89% had received it free. Independent predictors of vaccination were: belief that influenza vaccine is effective in preventing influenza (OR=13.5, 95% CI 10.6-17.2); and the presence of chronic disease (OR=1.6, 95% CI 1.3-2.0). Overall, 24% of those aged 40-64 years were vaccinated; only 34% of those who met any of the criteria for vaccination (medical risk factor, at-risk occupation, or being Aboriginal or Torres Strait Islander) reported vaccination., Conclusions: Influenza vaccine coverage was high in those aged > or = 65 years, but coverage of those at-risk aged 40-64 years remained suboptimal. Immunisation against influenza was influenced more by beliefs about the vaccine's effectiveness and existing medical risk factors, rather than socio-demographic factors such as gender and income.