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The effects of κ‐casein (κ‐CN) and β‐casein (β‐CN) genetic variant and κ‐CN glycosylation degree (GD, low or high) on interfacial and foaming properties of bovine skim milk were investigated. No significant effect was measured for milks with different ĸ‐CN and β‐CN genetic variants. However, milks of higher GD exhibited lower surface tension, enhanced foamability and differences in secondary protein structure compared to lower GD skim milks. Glycan attachment is believed to affect surface activity and the spread and packing of protein at the foam bubble liquid–air interface, leading to differences in foaming performance. [ABSTRACT FROM AUTHOR]

Background: The Questionnaire on Palliative Care for Advanced Dementia (qPAD) is increasingly being used to assess residential aged care workers' knowledge and attitudes about palliative care for people with dementia. The qPAD developers performed an exploratory factor analysis and assessed the internal consistency using a small sample. Aim: The aim of this study was to further assess the structural validity of the qPAD using a large sample of qPAD responses from staff who work in residential aged care homes in Australia. Methods: Data from 727 care staff who participated in an Australian dementia palliative care training project were used for exploratory factor analyses, assessment of internal consistency, and confirmatory factor analysis of the knowledge test and attitude scale components of the qPAD. Results: The exploratory factor analysis of the knowledge test produced a four‐factor solution. One item loaded weakly, and four items had cross‐loadings. Factor labels for the knowledge test were difficult to define. Factor analysis of the attitude scale produced a three‐factor structure with good internal consistency—Feeling valued and part of the care team (α = 0.88), Family and team engagement (α = 0.75) and Perceptions and beliefs (α = 0.83). Confirmatory factor analysis indicated improvements in model fit were needed for both the knowledge test and attitude scale. Conclusion: The findings of this factor analysis differed from the original study. The attitude scale produced a three‐factor structure, but the knowledge test requires further development due to weak and cross‐loadings of several items, inadequate internal consistency of factors and poor model fit. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to investigate the perceptions and beliefs of rural high school teachers about student suicide completion in their school and their perceived self‐efficacy in identification of suicidality in students (suicidal ideation, plans and behaviours). Design: A cross‐sectional survey methodology. Setting: Gippsland and the Loddon Mallee regions of Victoria, Australia. Participants: Rural high school teachers. Outcome Measure: A survey that aimed to obtain participants' perceptions and self‐reports about students who had died by suicide in their school within the last 5 years, their perceived self‐efficacy in identifying suicidal students and barriers to helping students at risk. Results: Two hundred and seventy‐seven rural high school teachers participated and 86% reported that a student from their school had died by suicide within the last 5 years. Sixty‐five per cent believed that more than one student had died by suicide and 70% perceived they were currently aware of students experiencing suicidality in their class. Receiving professional development about suicide and obtaining help from mental health clinicians predicted perceived self‐efficacy in identification of suicidality in students. Participants perceived the barriers to help students at risk included insufficient numbers of school‐based mental health professionals and community mental health services. Conclusions: Many rural high school teachers perceive they are at the front line of the youth suicide crisis due to unmet service need in youth mental ill health. Increased access to effective services immediately after teachers become aware of suicidality may assist in reducing youth suicide in rural areas. [ABSTRACT FROM AUTHOR]

Background and Aim: The role of circulating mitochondrial DNA (cmtDNA) in transplantation remains to be elucidated. cmtDNA may be released into the circulation as a consequence of liver injury; yet recent work also suggests a causative role for cmtDNA leading to hepatocellular injury. We hypothesized that elevated cmtDNA would be associated with adverse events after liver transplantation (LT) and conducted an observational cohort study. Methods: Twenty‐one patients were enrolled prospectively prior to LT. Results: Postoperative complications were observed in 47.6% (n = 10). Seven patients (33.3%) had early allograft dysfunction (EAD), and six patients (28.5%) experienced acute cellular rejection within 6 months of LT. cmtDNA levels were significantly elevated in all recipients after LT compared with healthy controls and preoperative samples (1 361 937 copies/mL [IQR 586 781–3 399 687] after LT; 545 531 copies/mL [IQR 238 562–1 381 015] before LT; and 194 562 copies/mL [IQR 182 359–231 515] in healthy controls) and returned to normal levels by 5 days after transplantation. cmtDNA levels were particularly elevated in those who developed EAD in the early postoperative period (P < 0.001). In all patients, there was initially a strong overall positive correlation between cmtDNA and plasma hepatocellular enzyme levels (P < 0.05). However, the patients with EAD demonstrated a second peak in cmtDNA at postoperative day 7, which did not correlate with liver function tests. Conclusions: The early release of plasma cmtDNA is strongly associated with hepatocellular damage; however, the late surge in cmtDNA in patients with EAD appeared to be independent of hepatocellular injury as measured by conventional tests. [ABSTRACT FROM AUTHOR]

In the estimation of proportions by group testing, unequal sized groups results in an ambiguous ordering of the sample space, which complicates the construction of exact confidence intervals. The total number of positive groups is shown to be a suitable statistic for ordering outcomes, provided its ties are broken by the MLE. We propose an interval estimation method based on this quantity, with a mid‐P correction. Coverage is evaluated using group testing problems in plant disease assessment and virus transmission by insect vectors. The proposed method provides good coverage in a range of situations, and compares favorably with existing exact methods. [ABSTRACT FROM AUTHOR]

Summary: Group testing, in which individuals are pooled together and tested as a group, can be combined with inverse sampling to estimate the prevalence of a disease. Alternatives to the MLE are desirable because of its severe bias. We propose an estimator based on the bias correction method of Firth (1993), which is almost unbiased across the range of prevalences consistent with the group testing design. For equal group sizes, this estimator is shown to be equivalent to that derived by applying the correction method of Burrows (1987), and better than existing methods. For unequal group sizes, the problem has some intractable elements, but under some circumstances our proposed estimator can be found, and we show it to be almost unbiased. Calculation of the bias requires computer‐intensive approximation because of the infinite number of possible outcomes. Estimation of proportions by group testing with inverse sampling results in a very biased MLE, but it can be substantially corrected using Firth's method. [ABSTRACT FROM AUTHOR]

Background: The reference intervals (RIs) for the renal biomarkers urea and creatinine, in Greyhounds, are higher than those for non‐sighthound breeds. A recent study has demonstrated a higher concentration of another biomarker of renal function, symmetric dimethylarginine (SDMA), in Greyhounds compared with other dog breeds, and thus a breed‐specific RI for serum SDMA may be appropriate for Greyhounds. Greyhounds appear to be predisposed to renal disease, and the establishment of an appropriate RI for SDMA may improve the ability to identify early renal dysfunction in this breed. Objectives: The aim of this study was to establish an RI for serum SDMA in nonracing Greyhounds and to determine whether the RI for Greyhounds is different from that of non‐sighthound breeds. Methods: Blood samples were collected from 101 clinically healthy, nonracing Greyhounds for serum SDMA measurements. Results from Greyhounds were compared with serum SDMA concentrations measured in a group of non‐sighthound dogs (n = 24) of similar weight, age, and sex, and with a previously established canine serum SDMA RI. Results: The serum SDMA RI for Greyhounds was 6.3‐19.9 μg/dL (0.31‐0.99 μmol/L). Greyhounds had a significantly higher mean value (13.1 μg/dL) than that of the non‐sighthound dogs (10.2 μg/dL) (P < .001), and the RI of Greyhounds was different from previously established canine RIs for SDMA. Conclusion: This study supports the use of a Greyhound‐specific RI for SDMA. Using previously established canine RIs for this breed could result in the overdiagnosis of renal disease. [ABSTRACT FROM AUTHOR]

Group testing is the process of combining individual samples and testing them as a group for the presence of an attribute. The use of such testing to estimate proportions is an important statistical tool in many applications. When samples are collected and tested in groups of different size, complications arise in the construction of exact confidence intervals. In this case, the numbers of positive groups has a multivariate distribution, and the difficulty stems from a lack of a natural ordering of the sample points. Exact two-sided intervals such as the equal-tail method based on maximum likelihood estimation, and those based on joint probability or likelihood ratio statistics, have been previously considered. In this paper several new estimators are developed and assessed. We show that the combined tails (or Blaker) method based on a suitable ordering statistic, is the best choice in this setting. The methods are illustrated using a study involving the infection prevalence of Myxobolus cerebralis among free-ranging fish. [ABSTRACT FROM AUTHOR]

ABSTRACT This study sought to investigate, using a case-control study design, the association between bisphosphonate therapy and delayed dental healing and osteonecrosis of the jaw. Identification of potential cases of delayed dental healing was by consecutive screening of Specialist Oral and Maxillofacial and Special Needs Dentist clinic records for patients aged older than 50 years, during a 6-month window, in Victoria, Australia. Cases were confirmed by a case adjudication panel blinded to bisphosphonate status. Cases associated with malignancy or local radiotherapy were excluded. Controls were matched for age, sex, and source of dental referral (1:4, n = 160 controls). Variables of interest were dental precipitants, dental clinic type, smoking history, and medical comorbidities. A total of 4212 of 22,358 patients met inclusion criteria, of which 69 were potential cases with 40 (0.95%) confirmed cases. The odds ratio (OR) for developing delayed dental healing when taking an oral bisphosphonate was 13.1 (95% confidence interval [CI] 4.4 to 39.3; p < 0.001). There were no cases associated with intravenous bisphosphonate use. There was some evidence of an interaction with age, sex, and clinic type. When adjusted for smoking, the estimated odds ratio was 11.6 (95% CI 1.9 to 69.4; p = 0.01). There was an association between having another illness and delayed dental healing (OR = 2.3; 95% CI 1.0 to 5.2). A dental precipitant was present in 39 of 40 (97.5%) delayed dental healing cases. An important association between bisphosphonate use and delayed dental healing in the setting of benign bone disease, predominately in individuals with a dental precipitant, has been demonstrated. © 2014 American Society for Bone and Mineral Research. [ABSTRACT FROM AUTHOR]

Site occupancy, as estimated by the probability of presence, is used for monitoring species populations. However, the detection of species at individual sites is often subject to errors. In order to accurately estimate occupancy we must simultaneously account for imperfect detectability by estimating the probability of detection. The problem with estimating occupancy arises from not knowing whether a nondetection occurred at an occupied site due to imperfect detectability (sampling zeros), or the nondetection resulting from an unoccupied site (fixed zeros). We evaluated the performance of the basic, normal approximation, studentised and percentile methods for approximating confidence limits for occupancy and detection of species. Using coverage and average interval width, we demonstrated that the studentised estimator was generally superior to the others, except when a small sample of sites are selected. Under this circumstance and when calculating limits for detection, no estimator produced reliable results. The experimental factors we considered include: (i) number of sites; (ii) number of survey occasions; (iii) probabilities of presence (occupancy) and detection; and (iv) overdispersion in the capture matrix. Similar conclusions were reached both for the simulated studies and a case study. Overall, estimation near the boundaries of the probability of occupancy and detectability was difficult. [ABSTRACT FROM AUTHOR]

Plutella xylostella and Pieris rapae are the key components of a pest complex that attacks Brassica crops in the Democratic People’s Republic of Korea (DPRK). We examined the spatial distributions of these insects within crops both as individual species and when combined as a standard insect that was derived from their relative feeding rates. The influence of standard co-operative management practice and an integrated pest management (IPM) strategy on the dispersion of the standard insect was tested. Iwao’s m* − m relation was then used to describe the distribution of standard insects by management categories and of Pieris rapae using all data. Pest management practices only affected the distribution of the species when they were combined into standard insects. Enumerative sampling plans were therefore designed for standard insects based on population data derived from IPM-managed fields and for Pieris rapae from population data from all experimental fields. The presented plans have the potential to make a significant contribution to managing lepidopteran pests in the DPRK. The approach will be useful in the design of sequential sampling plans for other geographical regions where these pests co-occur and can also contribute to the development of sequential sampling plans for other pest complexes for which standard insects can be derived. [ABSTRACT FROM AUTHOR]

The successful conservation and restoration of the temperate native grasslands of south-eastern Australia is critical to reversing the decline in range and diversity of these threatened plant communities. Yet the goals of high native species diversity and weed management are difficult to achieve in grassland restoration projects. To increase our understanding of whether synergies exist between these goals (i.e. whether early introduction of a larger number of species might improve both outcomes in the reassembly of native grassland), we examined the relationships between plant species number, functional group number and resource use during the establishment phase of direct-sown grassland. We did this by sowing a representative suite of species (at varying levels of species number and functional group number) into experimental plots and then measuring and analysing the extent to which the newly established assemblages captured available resources, i.e. used soil nitrate, absorbed light and produced biomass (vegetative cover). Statistically significant correlations were common between the predictor variables (species number, functional group number, percentage vegetative cover, plant number, presence of idiosyncratic (dominating) species) and responses (soil nitrate concentration, light reduction or ‘extinction’). Higher diversity was associated with lower soil nitrate, while percentage vegetative cover and the presence of idiosyncratic species best predicted light extinction. The relationship between diversity, and plant biomass (measured as vegetative cover) and plant number was positive in the first year of the study. The diversity/biomass relationship became negative in the second year due to the higher numbers and cover of ‘idiosyncratic’ species. The diversity/plant number relationship also became negative in the autumn of the second year and was reduced to a trend by the winter. We found that lower nitrate and increasing plant numbers and vegetative cover were most strongly linked to increasing species number in the early stages of this study. This suggests that introducing and maintaining high diversity early in a native grassland reassembly or enhancement project will improve the resistance (e.g. to weed) of these communities. At later stages of grassland development, this function may be provided by the more dominating idiosyncratic species. The maintenance of diversity, an important goal in its own right, will therefore necessitate managed disturbances to periodically reduce the vegetative dominance of idiosyncratic species, releasing resources for the diverse range of other species whose early introduction will have allowed them to persist in the soil seed bank or as suppressed rootstocks. [ABSTRACT FROM AUTHOR]

Objective: To review psychiatrists’ attitudes and actual practice on the use of typical and atypical antipsychotics in the elderly. Methods: Audit data were collected from 18-old-age psychiatry units across Australia. The attitudes of old age psychiatrists and their perceptions of the efficacy, tolerability and clinical usefulness of antipsychotics were examined. Results: The medications used for 321 patients were audited, and the attitudes of the 57 prescribing doctors were assessed. All available atypicals were prescribed and reported as more efficacious and clinically useful than typicals. Adverse events perceived by doctors as an obstacle to prescribing were more frequent than reported adverse event rates in product information. All diagnostic groups improved. Off-label use comprised almost 22% in this sample. Conclusions: Adverse events are impediments to prescribing, more so with typical than atypical antipsychotics. All available atypicals were used and appeared effective in this elderly population. [ABSTRACT FROM AUTHOR]

Group testing has been used in many fields of study to estimate proportions. When groups are of different size, the derivation of exact confidence intervals is complicated by the lack of a unique ordering of the event space. An exact interval estimation method is described here, in which outcomes are ordered according to a likelihood ratio statistic. The method is compared with another exact method, in which outcomes are ordered by their associated MLE. Plots of theP-value against the proportion are useful in examining the properties of the methods. Coverage provided by the intervals is assessed using several realistic grouptesting procedures. The method based on the likelihood ratio, with a mid-Pcorrection, is shown to give very good coverage in terms of closeness to the nominal level, and is recommended for this type of problem. [ABSTRACT FROM AUTHOR]

A response from the author of the article "Bisphosphonate Exposure and Osteonecrosis of the Jaw" in the 2014 issue is presented.