Peak modeling approach to accurate assignment of first-dimension retention times in comprehensive two-dimensional chromatography

Modeling of first-dimension retention of peaks based on modulation phase and period allows reliable prediction of the modulated peak distributions generated in the comprehensive two-dimensional chromatography experiment. By application of the inverse process, it is also possible to use the profile of the modulated peaks (their heights or areas) to predict the shape and parameters of the original input chromatographic band (retention time, standard deviation, area) for the primary column dimension. This allows an accurate derivation of the firstdimension retention time (RSD 0.02%) which is equal to that for the non-modulated experiment, rather than relying upon the retention time of the major modulated peak generated by the modulation process (RSD 0.16%). The latter metric can produce a retention time that differs by at least the modulation period employed in the experiment, which displays a discontinuity in the retention time vs modulation phase plot at the point of the 180° out-ofphase modulation. In contrast, the new procedure proposed here gives a result that is essentially independent of modulation phase and period. This permits an accurate value to be assigned to the first-dimension retention. The proposed metric accounts for the time on the seconddimension, the phase of the distribution, and the holdup time that the sampled solute is retained in the modulating interface. The approach may also be based on the largest three modulated peaks, rather than all modulated peaks. This simplifies the task of assigning the retention time with little loss of precision in band standard deviation or retention time, provided that these peaks are not all overloaded in the first or second dimension.

Scientists and the cultural politics of academic disciplines in late 19th-century Germany: Emil Du Bois-Reymond and the controversy over the role of the cultural sciences

This article is concerned with interactions between the natural and the human sciences. It examines a specific late 19th-century episode in their relationship and argues that the schism between the two branches of knowledge was due to cognitive factors, but consolidated through the social dynamics of institutionalized disciplines. It contends that the assignment of a social function to the human sciences to compensate for the self-destructive tendencies inherent in the technological society was expressed even by those, at the end of the 19th century, who were fervent advocates of a science- and technology-driven modernization.

Characterisation of a synthesised fluorescent ligand (4-acridinol-1-sulphonic acid) using nuclear magnetic resonance spectroscopy

The synthesis and complete characterisation of the fluorescent ligand, 4-acridinol-1-sulphonic acid (the acridine analogue of 8-quinolinol-5-sulfonic acid) is described. Using a judicious array of nuclear magnetic resonance spectroscopy experiments, the structural elucidation and full assignment of all proton and carbon chemical shifts were afforded. The 4-acridinol-1-sulphonic acid was found to behave in a similar manner to 8-quinolinol-5-sulphonic acid, forming fluorescent complexes with magnesium(II) and zinc(II). The uncorrected emission maxima for the metal–acridinol complexes were found to be at around 620 nm compared to 505 nm for the respective quinolinol complexes. Unfortunately, preliminary spectrofluorimetric analytical figures of merit revealed that the detection limits of the new acridinol metal complexes were one and a half orders of magnitude poorer than those attained with the corresponding quinolinol ligand. However, in contrast to 8-quinolinol-5-sulphonic acid, the 4-acridinol-1-sulphonic acid ligand showed considerable selectivity for magnesium(II) and zinc(II) over aluminium(III).

Do logbooks influence recall of physical activity in validation studies?

Purpose: To examine whether physical activity logbooks influence estimates of validity of 7-d recall physical activity questionnaires. Methods: A  convenience sample of 551 adults aged 18–75 yr wore an MTI  accelerometer for seven consecutive days and were then randomly administered two of four 7-d recall physical activity questionnaires that varied in length and format (Active Australia Survey (AAS), long and short  International Physical Activity Questionnaires (IPAQ-L and IPAQ-S), and Behavioral Risk Factor Surveillance System (BRFSS)). A subsample of 75% concurrently completed a physical activity logbook. Results: Correlations (rho) between self-reported and measured duration of moderate- and vigorous-intensity activity and total activity were similar among participants who received a logbook and those who did not for each of the four instruments. There was also no interaction between assessment method (survey, accelerometer) and the assignment of a logbook. For the IPAQ-L, however, variability in the difference between accelerometer data and responses to the vigorous items was smaller among those assigned a logbook (F = 4.128, df = 260, P = 0.043). Overall, there were no differences in percent agreement or kappa for participation in sufficient levels of physical activity according to receipt of a logbook for any of the surveys. Conclusion: The process of self-monitoring through completion of a logbook does not appear to influence estimates of validity for brief or long questionnaires with global questions. Whereas the magnitude of error in accuracy of recall of particular types of activity may be reduced by completion of a logbook that is similar in structure to the survey being validated, this does not appear to influence overall estimates of validity.

The limitations of using statutory child protection data for research into child maltreatment

Child protection legislation has undergone a number of changes since its inception, changes that have redefined the population of children in need of protection. However, child protection data on notifications and substantiations remain the most common source of data for statistics on the rate of maltreatment and the breakdown of specific maltreatment types. In the present study, three factors are identified that have compromised the accuracy of child protection data reporting the incidence of child abuse and neglect: (i) the legislative changes that mandate child protection services to protect children from harm rather than from identifiable adult actions; (ii) the shift from the Harm Standard to the Endangerment Standard; and (iii) the assignment of responsibility solely to parents.

Reproducibility of digital evidence in forensic investigations

We present a three-component model of a digital investigation which comprises: determination of input-output layers, assignment of read and write operations associated with use of forensic tools, and time-stamping of read and write operations. This builds on work of several authors, culminating in the new model presented here which is generic, scalable and compatible with all functions in the system, and which is guaranteed to produce a high quality of reproducibility.

Gas chromatography-chemical ionization-mass spectrometric fatty acid analysis of a commercial supercritical carbon dioxide lipid extract from New Zealand green-lipped mussel (Perna canaliculus)

Supercritical fluid extracts of New Zealand green-lipped mussels (NZGLM) have been suggested to have therapeutic properties related to their oil components. The large number of minor FA in NZGLM extract was characterized by a GC-CIMS/MS method that excels at identification of double-bond positions in FAME. The extract contained five major lipid classes: sterol esters, TAG, FFA, sterols, and polar lipids. The total FA content of the lipid extract was 0.664 g/mL. Fifty-three unsaturated FA (UFA) were fully identified, of which 37 were PUFA, and a further 21 UFA were detected for which concentrations were too low for assignment of double-bond positions. There were 17 saturated FA, with 14∶0, 16∶0, and 18∶0 present in the greatest concentration. The 10 n−3 PUFA detected included 20∶5n−3 and 22∶6n−3, the two main n−3 FA; n−3 PUFA at low concentrations were 18∶3, 18∶4, 20∶3, 20∶4, 21∶5, 22∶5, 24∶6, and 28∶8. There were 43 UFA from the n−4, n−5, n−6, n−7, n−8, n−9, n−10, n−11 families, with 16∶2n−4, 16∶1n−5, 18∶1n−5, 18∶2n−6, 20∶4n−6, 16∶1n−7, 20∶1n−7, 16∶1n−9, 18∶1n−9, and 20∶1n−9 being the most abundant. In general, we estimated that FAME concentrations greater than 0.05% (w/w) were sufficient to assign double-bond positions. In total, 91 FA were detected in an extract of the NZGLM, whereas previous studies of fresh flesh from the NZGLM had reported identification of 42 FA. These data demonstrate a remarkable diversity of NZGLM FA.

An evaluation of three field techniques for sexing live Gould's petrels (Pterodroma leucoptera) (Procellariidae)

Many petrels show no obvious sex-linked dimorphism in plumage or size and consequently many researchers fail to sex the living individuals they study. Several methods of sex discrimination that do not rely on plumage- or obvious size-dimorphism can be used to sex live petrels. The effectiveness of three such techniques was evaluated: body condition at the time of laying, cloacal inspection, and discriminant function analysis (DFA) of external morphometrics. Gould’s Petrel (Pterodroma leucoptera leucoptera) was used as the subject species. Sexing of breeding adults on the basis of body condition at laying proved to be highly accurate (100% of birds sexed correctly) but required detailed knowledge of the breeding biology. Following training, cloacal inspection proved to be an accurate (96%) method of determining the sex of breeding adults, but not of chicks. Unlike molecular sexing, the latter two methods of sex discrimination provide immediate knowledge of the sex of individuals in the field. DFA of external morphometrics predicted the sex of adults with an accuracy of 73% and the sex of near-fledged chicks with an accuracy of 66%. However, the probability of correct assignment of sex was low in most cases and, therefore, this is the least useful of the three techniques assessed here.

The procedural validity of retrospective case note diagnosis

Objective: Deriving diagnoses from retrospective case note examination is a common practice in psychiatric research. The Operational Criteria (OPCRIT) diagnostic checklist is essentially a checklist built up of operational criteria defined by a comprehensive glossary and is designed to assign reliable diagnoses from case notes. However, the validity of such a procedure compared with procedures involving prospective assessment has never been tested. We examined the procedural validity of the OPCRIT diagnostic system in relation to four other diagnostic procedures mostly employing prospectively gathered information.

Method: Three experienced psychopathology raters rated the case notes and clinical abstracts, using the OPCRIT method of diagnostic assignment, of 50 subjects who had participated in an early procedural validity study as an adjunct to the DSM-IV Field Trial for psychotic disorders. The setting was the Early Psychosis Prevention and Intervention Centre (EPPIC), which focuses on first episode psychosis.

Results: The pairwise concordance with the other procedures for DSM-III-R diagnoses assigned by OPCRIT using ratings derived from either the clinical abstracts or the case notes was found to be only poor to moderate when compared with the pairwise concordance of the four other procedures. The per cent agreement between OPCRIT clinical abstracts diagnoses and the other procedures ranged from 49% to 60% with kappa values between 0.30 and 0.45, and for OPCRIT case note diagnoses and the other procedures the per cent agreement range was between 44% and 57% and the kappa values were between 0.35 and 0.49.

Conclusions: The procedural validity of diagnoses assigned via the application of checklists of operational criteria to case notes and clinical abstracts alone is unacceptably poor. Such sources need to be buttressed by other data, particularly direct patient interview and informant material.

Agency-nursing work : perceptions and experiences of agency nurses

This paper explores agency-nursing work from the perspective of agency nurses to gain in-depth understanding of their clinical practice, their relationships with the employing agency, hospitals and permanent nurses, and their professional status. For this study, individual interviews were conducted with ten agency nurses who were registered with one of three nursing agencies in Melbourne, Australia. Five major themes emerged from interview data: orientation, allocation of agency nurses, reasons for doing agency-nursing work, experiences with hospital staff, and professionalism. The findings reveal that the primary reason for nurses engaging in agency-nursing work is for the flexibility it offers. While agency nurses described a commitment to professionalism, the findings emphasise the need to establish effective communication networks between agency nurses, nursing agencies and hospital institutions. Such communication between stakeholders is important to facilitate discussion of issues such as appropriate notification of shift availability, appropriate assignment of work and recognition of the agency nurse as a valuable member of the health care team. In particular, the findings highlight the importance of comprehensive orientation and education for agency nurses to shift the focus of their daily work from task completion to more comprehensive patient care.

Discourse of conscience in the assessment of voluntary assignments in equity

This article examines the continuing suitability of the existing Australian test for determining when a voluntary assignment of legal property has passed in equity. It suggests that the current test, which focuses upon the ‘completion’ by the donor of the all the necessary transfer formalities, and the underlying equitable maxims that support it, should be revised to better reflect the dual concerns of assignment and constructive trust. The article reviews the English authorities, in particular the English Court of Appeal in Pennington v Waine, which held that the equitable jurisdiction can validate a voluntary assignment of legal property where, in the circumstances, it would be unconscionable to allow the donor to resile. It is argued that this approach represents an appropriate progression because it provides greater scope for a particularised examination of the intention, circumstances and behaviour surrounding the purported assignment. A test which encourages greater contextual examination of the overall circumstances underlying the assignment process is consistent with the core expectations of equitable methodology. It supports the multi-layered process of determining whether a donor intended the assignment and further, whether that donor should be held liable as constructive trustee.

Comparative analysis of surface-enhanced Raman spectroscopy of daidzein and formononetin

Phytoestrogens daidzein (4′,7-dihydroxy-isoflavone) and formononetin (4′-methoxy-7-hydroxy-isoflavone) have been studied by surface-enhanced Raman (SER) spectroscopy. Spectra were acquired in the presence of citratereduced silver colloids, over a range of pH and concentrations. Density functional theory calculations were used to assist assignment of the normal Raman spectra and help determine the mode of interaction of isoflavones with the silver nanoparticles. Formononetin does not show SER activity unless the 7-OH group is deprotonated, and accordingly, the interaction with the silver surface occurs via the deprotonated site. Daidzein, on the other hand, appears to contain multiple species at the surface, interacting via both the hydroxyl groups at 7-OH and 4′-OH, after deprotonation. This is an important result that points to potential future SERS applications in phytoestrogen analysis and provides a foundation for understanding the SER spectra of isoflavones.

Working collaboratively in a group assignment using a Mediawiki for an architecture and construction management undergraduate unit

This paper describes an architecture and construction management unit which implements Mediawiki in teaching and learning. The main objective of using the Mediawiki is to engage students to work collaboratively online in a group assignment. It also aims to further develop student information technology skills and thus enhance their learning experience. One of the learning objectives of the unit is to develop the ability to communicate the results of student research in construction technology using appropriate digital media from which Mediawiki was chosen. This paper outlines the challenges and issues faced in the implementation of Mediawiki as a collaborative tool in a group assignment of an architecture and construction management unit. It also discusses how academic staff and students were supported through the process of learning to use the Mediawiki. Finally, potential future directions of using Mediawiki in teaching and learning are explored based on students’ comments and feedback.

Investigation of population heterogeneity of diet use among middle-aged Australians

The purpose of the study was to determine patterns of diet use among middle-aged Australian men and women and the relationships between these different usage patterns and demographic characteristics, health status and health habits. A cross-sectional mail survey was conducted among a random sample of 2975 people aged 40–71 years in Victoria, Australia. A total of 1031 usable questionnaires were obtained which included information about the use of diets (e.g. low-fat and low-salt) during the past 3 months along with demographic information, health status and health habits. Based on the responses about the use of thirteen diets for both sexes, latent class analysis was employed to identify the optimal number of use of diets and the assignment of participants to particular groups. Three types of diet uses were identified and provisionally named: diet use, selected diet use and non-diet use. This classification was associated with demographics, health status and health habits, and these associations differed between men and women. The findings suggest that nutrition education programmes should be tailored to the different needs of the diet use groups.

Recognising behaviours of multiple people with hierarchical probabilistic model and statistical data association

Recognising behaviours of multiple people, especially high-level behaviours, is an important task in surveillance systems. When the reliable assignment of people to the set of observations is unavailable, this task becomes complicated. To solve this task, we present an approach, in which the hierarchical hidden Markov model (HHMM) is used for modeling the behaviour of each person and the joint probabilistic data association filters (JPDAF) is applied for data association. The main contributions of this paper lie in the integration of multiple HHMMs for recognising high-level behaviours of multiple people and the construction of the Rao-Blackwellised particle filters (RBPF) for approximate inference. Preliminary experimental results in a real environment show the robustness of our integrated method in behaviour recognition and its advantage over the use of Kalman filter in tracking people.