Nonlinear dynamics of EEG responses to unmanned vehicle visual detection with different levels of task difficulty

The main objective of this study was to examine the presence of chaos in the EEG recordings of brain activity under simulated unmanned ground vehicle visual detection scenarios with different levels of task difficulty. One hundred and fifty people participated in the experiment and completed four visual detection task scenarios: (1) change detection, (2) a threat detection task, (3) a dual-task with different change detection task rates, and (4) a dual-task with different threat detection task rates. We used the largest Lyapunov exponent and correlation dimension of the EEG data and performed 0-1 tests on the EEG data. The results revealed a change in the level of nonlinearity in the EEG data corresponding to different levels of cognitive task difficulty. The differences in EEG nonlinearity measures among the studied levels of task difficulty, as well as between a single task scenario and a dual-task scenario, have also been assessed. The results increase our understanding of the nature of unmanned systems' operational requirements.

Simultaneous Determination of Nine Phthalates in Vegetable Oil by Atmospheric Pressure Gas Chromatography with Tandem Mass Spectrometry (APGC-MS/MS)

Although the use of phthalates has been restricted worldwide, they remain an issue due to health concerns. Diet is one of the most important exposure pathways for humans and due to their solubility in oil, phthalates are commonly found in edible oil and food high in fat. Gas chromatography-mass spectrometry (GC-MS) using electron ionization (EI) has been commonly used for the analysis of the phthalates in foodstuffs, including edible oil. However, this method suffers from issues with sensitivity and selectivity, as most phthalates are fragmented to generate a common phthalic anhydride fragment ion at m/z 149. The molecular ion cannot be observed due to strong fragmentation in EI. In contrast, atmospheric pressure gas chromatography (APGC) is a soft ionization technique with less fragmentation, whereby the molecular ion can be used as the precursor ion for multiple reaction monitoring (MRM). In this study, a simple and quick method for the determination of phthalates in vegetable oil using APGC-MS/MS was developed, and performance was assessed. The method was based on dilution of the oil in solvent and direct injection without the need for further cleanup. The established method was evaluated for linearity, recovery, precision, method detection limit (MDL), and method quantitation limit (MQL). The obtained MQL in vegetable oil was in the range of 0.015-0.058 mg/kg, despite limiting the injection volume to 1 µL, which is suitable for investigating dietary exposure and future proof against decreases to the regulatory limit. Finally, the developed method was successfully applied to analyze nine phthalates in eight commercially available vegetable oil.

A novel screening method for free non-standard amino acids in human plasma samples using AccQ·Tag reagents and LC-MS/MS

There are at least 500 naturally occurring amino acids, of which only 20 standard proteinogenic amino acids are used universally across all organisms in the synthesis of peptides and proteins. Non-standard amino acids can be incorporated into proteins or are intermediates and products of metabolic pathways. While the analysis of standard amino acids is well-defined, the analysis of non-standard amino acids can be challenging due to the wide range of physicochemical properties, and the lack of both reference standards and information in curated databases to aid compound identification. It has been shown that the use of an AccQ·Tag™ derivatization kit along with LC-MS/MS is an attractive option for the analysis of free standard amino acids in complex samples because it is fast, sensitive, reproducible, and selective. It has been demonstrated that the most abundant quantitative transition for MS/MS analysis of 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) derivatized amino acids corresponds to the fragmentation of the molecule at the 6-aminoquinoline carbonyl group producing a common m/z 171 fragment ion and occurs at similar mass spectrometry collision energy and cone voltages. In this study, the unique properties of AQC derivatized amino acids producing high intensity common fragment ions, along with chromatographic separation of amino acids under generic chromatography conditions, were used to develop a novel screening method for the detection of trace levels of non-standard amino acids in complex matrices. Structural elucidation was carried out by comparing the MS/MS fragment ion mass spectra generated with in silico predicted fragmentation spectra to enable a putative identification, which was confirmed using an appropriate analytical standard. This workflow was applied to screen human plasma samples for bioactive thiol-group modified cysteine amino acids and S-allylmercaptocysteine (SAMC), S-allylcysteine sulfoxide (SACS or alliin) and S-propenylcysteine (S1PC) are reported for the first time to be present in human plasma samples after the administration of garlic supplements.

Honey authenticity: the opacity of analytical reports-part 2, forensic evaluative reporting as a potential solution

The analytical techniques applied to verify honey authenticity are multifaceted and often result in complex data rich certificates of analysis that are open to interpretation and may be opaque to stakeholders without specialist knowledge. In these cases, the drawing of an independent overarching opinion is challenging. Two questions arise: (Q1) Is it acceptable to report interpretation, particularly if it is adverse, without exhibiting the supporting data? (Q2) How may a valid overarching opinion on authenticity be derived from a large, partially conflicting, dataset? To Q1, it is demonstrated that full disclosure of the data used in interpretation is mandatory. To Q2 it is proposed, with worked examples, to adopt ‘evaluative reporting’; a formalised likelihood ratio thought process used in forensic science for evaluation of findings and their strength assessment. In the absence of consensus on techniques for honey authenticity adoption of reporting conventions will allow objective assessments of reports, with equity to all and provide a better basis to identify and address fraud.

Evaluating paediatric dermatology telephone clinics during COVID-19 from a dual clinician and patient perspective: a prospective study

BACKGROUND

The landscape of dermatology services, already rapidly evolving into an increasingly digital one, has been irretrievably altered by the COVID-19 (SARS-CoV-2) pandemic. Data are needed to assess how best to deliver virtual dermatology services in specific patient subgroups in an era of ongoing social distancing and beyond. Initial studies of teledermatology in paediatric populations suggest that many of the problems experienced in adult telemedicine are more apparent when treating children and come with additional challenges.

AIM

To evaluate the efficacy of a virtual paediatric dermatology telephone clinic in comparison to traditional face-to-face (FTF) clinics, both from the clinician and patient/parental perspective.

METHODS

We carried out a prospective service evaluation examining a single centre cohort of paediatric dermatology patients managed during the COVID-19 pandemic via a telephone clinic supported by images. The study period covered June-September 2020. Data on outcomes were collected from clinicians and a qualitative patient/parental telephone survey was undertaken separately. A five-point Likert scale was used to assess both satisfaction and levels of agreement regarding whether a telephone clinic was more convenient than an FTF clinic.

RESULTS

Of 116 patients included, 24% were new and 76% were follow-up patients, with a mixture of inflammatory dermatoses (75%) and lesions (25%). From the clinician's perspective, most consultations (91%) were successfully completed over the telephone. However, qualitative patient and parent feedback paradoxically illustrated that although nearly all (98%) respondents had no outstanding concerns, 52% felt highly unsatisfied and only 22% agreed that telephone clinics were more convenient. Most (65%) preferred FTF follow-up in the future. Statistical analysis using χ² test showed that among those with established follow-ups, the preference for future consultation type was independent of specific reasons for follow-up.

CONCLUSIONS

Our study demonstrates a clear discrepancy between the practical successes of a virtual service from the clinician's perspective compared with the patient/parental perspective. Parental anxiety appears to be less effectively allayed virtually than with FTF. This raises the question of whether there is a role for virtual paediatric telephone clinics in the postpandemic future, which may be better left to patients/parents to decide on an individual basis.

Enhancing the effectiveness of human-robot teaming with a closed-loop system

With technological developments in robotics and their increasing deployment, human-robot teams are set to be a mainstay in the future. To develop robots that possess teaming capabilities, such as being able to communicate implicitly, the present study implemented a closed-loop system. This system enabled the robot to provide adaptive aid without the need for explicit commands from the human teammate, through the use of multiple physiological workload measures. Such measures of workload vary in sensitivity and there is large inter-individual variability in physiological responses to imposed taskload. Workload models enacted via closed-loop system should accommodate such individual variability. The present research investigated the effects of the adaptive robot aid vs. imposed aid on performance and workload. Results showed that adaptive robot aid driven by an individualized workload model for physiological response resulted in greater improvements in performance compared to aid that was simply imposed by the system.

Central venous Access device SeCurement And Dressing Effectiveness for peripherally inserted central catheters in adult acute hospital patients (CASCADE): a pilot randomised controlled trial

Background

Peripherally inserted central catheters (PICCs) are commonly used for delivering intravenous therapy. PICC failure is unacceptably high (up to 40%) due to mechanical, infectious and thrombotic complications. Poor securement potentiates all complication types. This randomised controlled trial (RCT) aimed to examine the feasibility of a large RCT of four dressing and securement methods to prevent PICC failure.

Methods

This single-centre pilot RCT included 124 admitted medical/surgical/cancer patients aged ≥ 16 years with a PICC. Interventions were: (i) standard polyurethane dressing and sutureless securement device (SPU + SSD, control); (ii) polyurethane with absorbent lattice pad dressing (PAL + Tape); (iii) combination securement-dressing (CSD); and (iv) tissue adhesive (TA + SPU). All groups except TA + SPU had a chlorhexidine-gluconate (CHG) impregnated disc. Feasibility outcomes were recruitment and safety/acceptability of the interventions. The primary outcome was PICC failure, a composite of PICC removal for local infection, catheter-associated bloodstream infection, dislodgement, occlusion, and/or catheter fracture. Secondary outcomes included individual complications, dressing failure and dwell time, PICC dwell time, skin complications/phlebitis indicators, product costs, and patient and staff satisfaction. Qualitative feedback was also collected.

Results

PICC failure incidence was: PAL + CHG + Tape (1/5; 20%; 17.4/1000 days), SPU + SSD + CHG (control) (4/39; 10%; 9.0/1000 days), TA + SPU (3/35; 9%; 9.6/1000 days), and CSD + CHG (3/42; 7%; 9.4/1000 days). Recruitment to PAL + CHG + Tape was ceased after five participants due to concerns of PICC dislodgement when removing the dressing. CSD + CHG, TA + SPU (TA applied only at PICC insertion time), and control treatments were acceptable to patients and health professionals.

Conclusion

A large RCT of CSD + CHG and TA + SPU (but not PAL + CHG + Tape) versus standard care is feasible.

Trial registration

Australian and New Zealand Clinical Trials Registry, ACTRN12616000027415. Registered on 15 January 2016.

The Effects of Computer User Handedness on a Mouse-Clicking Task

The present study examined computer user handedness on a motor task using Fitts’s Law. Results indicated that right-handed participants were significantly faster than the left-handed participants when performing the motor task as measured by the Index of Performance. This finding could be partially attributed to the mouse design that is inconsistent with differential user handedness. Conversely, this finding could also be partially attributed to the degree of training left-handed participants received relative to their right-handed counterparts. The right-handed users outperformed their counterpart left-handed users perhaps because of physical design biases or relative degree of training. The present findings have practical implications for computer input device such as game controllers, joysticks, or mice that are physically designed for right-handed users.

Workload Change Over Time for Nuclear Power Plant Operation Tasks

Nuclear Power Plant (NPP) operation requires multiple task types to complete necessary day-to-day activities and operating procedures. The accurate completion of these tasks is necessary for safety-critical domains, as errors and omissions can potentially result in severe consequences. As a result, it is important to determine the cause of human error within various task types. One factor that contributes to human performance is workload. The present experiment is a follow-up, further investigating levels of workload, within a NPP simulated environment, with experienced participants. EEG, ECG, and the NASA-TLX have been shown to be sensitive to changes in workload across domains and are thus utilized in the present experiment to record workload differences. Specifically, the present experiment investigated these participants across 27 sessions for three different NPP task types –checking, detection, and response implementation.

Politeness in Machine-Human and Human-Human Interaction

Computers communicate with humans in ways that increasingly resemble interactions between humans. Nuances in expression and responses to human behavior become more sophisticated, and they approach those of human-human interaction. The question arises whether we want systems eventually to behave like humans, or whether systems should, even when much more developed, still adhere to rules that are different from the rules governing interpersonal communication. The panel addresses this issue from various perspectives, eventually aiming to gain some insights into the question of the direction to which the development of machine-human communication and the etiquette implemented in the systems should move.

Human-Centered Design of Unmanned Aerial Vehicles

Technology advances and increased application of UAVs will demand greater attention to human factors concerns in design, deployment, and training.

Breaking the Isolation Cycle: The Experience of Muslim Refugee Women in Australia

Based on the findings of focus groups and key informant interviews, an ‘isolation cycle’ is proposed to conceptualize the interrelated processes that marginalize first generation migrant Muslim refugee women from meaningful participation in Australian society. We hold that both internal ‘ethnic’ factors and external societal factors are jointly involved in perpetuating a cycle of isolation for Muslim refugee women. Hence, we propose that the tendency of social analysts, politicians and media commentators alike to focus on one group over the other as a means of casting ‘blame’ on difficulties surrounding integration is misguided. We conclude that more attention is required by Australian services and government agencies in breaking the isolation cycle through a more sustained, pro-active strategy directed not only at refugee settlers, but Australian society in general.

2016 Laboratory guidelines for postvasectomy semen analysis: Association of Biomedical Andrologists, the British Andrology Society and the British Association of Urological Surgeons

Post-vasectomy semen analysis (PVSA) is the procedure used to establish whether sperm are present in the semen following a vasectomy. PVSA is presently carried out by a wide variety of individuals, ranging from doctors and nurses in general practitioner (GP) surgeries to specialist scientists in andrology laboratories, with highly variable results.

Key recommendations are that: (1) PVSA should take place a minimum of 12 weeks after surgery and after a minimum of 20 ejaculations. (2) Laboratories should routinely examine samples within 4 h of production if assessing for the presence of sperm. If non-motile sperm are observed, further samples must be examined within 1 h of production. (3) Assessment of a single sample is acceptable to confirm vasectomy success if all recommendations and laboratory methodology are met and no sperm are observed. Clearance can then be given. (4) The level for special clearance should be <100 000/mL non-motile sperm. Special clearance cannot be provided if any motile sperm are observed and should only be given after assessment of two samples in full accordance with the methods contained within these guidelines. Surgeons are responsible both preoperatively and postoperatively for the counselling of patients and their partners regarding complications and the possibility of late recanalisation after clearance. These 2016 guidelines replace the 2002 British Andrology Society (BAS) laboratory guidelines and should be regarded as definitive for the UK in the provision of a quality PVSA service, accredited to ISO 15189:2012, as overseen by the United Kingdom Accreditation Service (UKAS).

Sources, incidence and effects of non-physical workplace violence against nurses in Ghana

AIM

To document the incidence, sources and effects of workplace verbal abuse and sexual harassment against Ghanaian nurses.

METHODS

A cross-sectional study was conducted in Ghana from 2013-2014 which surveyed 592 professional nurses and midwives working in public hospitals in Ghana using the health sector violence questionnaire.

RESULTS

The majority of participants were females (80%). The average age of participants was 31·76 years and the average number of years practising as nurse was 7·38. Twelve per cent of the participants experienced at least one incident of sexual harassment and 52·2% were exposed to verbal abuse. The majority of perpetrators of sexual harassment were medical doctors (50%). Relatives of patients emerged as the most frequent verbal abusers (45·5%). Chi-square test showed statistically significant associations between gender and workplace violence and between workplace violence and intention to quit the nursing profession. The effects of workplace violence ranged from having disturbing memories about the incident to being 'super alert' and vigilant. Establishing the incidence of workplace violence is a necessary step towards addressing the problem. It is concluded that educational programs must be designed for healthcare workers and the general public to foster awareness of the effects of workplace violence. Clear policies must also be instituted to address the problem.

Perceptions of pregnancy experiences when using a community-based antenatal service: A qualitative study of refugee and migrant women in Perth, Western Australia

BACKGROUND

Equality of care in pregnancy is important for all women, however can be difficult for healthcare providers to achieve. It has been found that culturally and linguistically diverse women born overseas generally have lower satisfaction with pregnancy care than women born in the host country.

AIM

Using a phenomenological framework, and models of care as a conceptual framework, this study explored the perceptions of care experienced by refugees and migrant women of culturally and linguistically diverse backgrounds who had participated in a community-based antenatal programme specialising in maternity care of multicultural women.

METHOD

Informants were twelve women aged between 23 and 44 years of age; one woman was 33 weeks pregnant, other women had given birth in the six months prior to data collection. Semi-structured interviews were conducted, using interpreters for women who spoke little or no English. Data were analysed using thematic analysis.

FINDINGS

Four main themes were identified; Social Support, Gaining of Knowledge, A Holistic Service, and New Opportunities.

CONCLUSION

Using a community-based antenatal service specialising in maternity care of women from culturally and linguistically diverse backgrounds enabled the needs of refugee and migrant women to be recognised and met, and therefore enhanced their perception of the pregnancy experience.

Advancing a sociotechnical systems approach to workplace safety--developing the conceptual framework

Traditional efforts to deal with the enormous problem of workplace safety have proved insufficient, as they have tended to neglect the broader sociotechnical environment that surrounds workers. Here, we advocate a sociotechnical systems approach that describes the complex multi-level system factors that contribute to workplace safety. From the literature on sociotechnical systems, complex systems and safety, we develop a sociotechnical model of workplace safety with concentric layers of the work system, socio-organisational context and the external environment. The future challenges that are identified through the model are highlighted.

PRACTITIONER SUMMARY

Understanding the environmental, organisational and work system factors that contribute to workplace safety will help to develop more effective and integrated solutions to deal with persistent workplace safety problems. Solutions to improve workplace safety need to recognise the broad sociotechnical system and the respective interactions between the system elements and levels.

Test Your Memory test: diagnostic utility in a memory clinic population

BACKGROUND

Test Your Memory (TYM) test is a recently described cognitive test instrument designed to be self-administered under medical supervision. The pragmatic role of such self-administered tests in cognitive clinics has not previously been examined. We investigated the diagnostic utility of the TYM as an independent test to differentiate patients with and without dementia at initial clinical diagnostic interview in dedicated memory clinics.

METHODS

TYM was administered to consecutive new patient referrals to two memory clinics independent of other tests [Mini-Mental State Examination (MMSE) and the Addenbrooke's Cognitive Examination-Revised] which were used to establish diagnoses according to standard diagnostic criteria (DSM-IV), and results were compared.

RESULTS

In a cohort of 224 patients, 35% fulfilling clinical diagnostic criteria for dementia, TYM proved easy to use and acceptable to patients. Downward adjustment of the TYM test cutoff to ≤30/50, compared to ≤42/50 used in the index study, proved necessary to maximise test accuracy and specificity. Using this revised cutoff, TYM showed comparable diagnostic utility (sensitivity 0.73, specificity 0.88, positive predictive value 0.77, negative predictive value 0.86 and area under receiver operating characteristic curve 0.89) to the MMSE and the Addenbrooke's Cognitive Examination-Revised for the differentiation of cases of dementia from non-dementia.

CONCLUSIONS

TYM is a useful screening test in the cognitive function clinic setting, with patients who fall below the designated cutoff requiring further investigation to ascertain a cause for their cognitive impairment. Self-administered tests such as TYM may be of particular value in situations where clinician time is limited.

The relative importance of external and internal features of facial composites

Three experiments are reported that compare the quality of external with internal regions within a set of facial composites using two matching-type tasks. Composites are constructed with the aim of triggering recognition from people familiar with the targets, and past research suggests internal face features dominate representations of familiar faces in memory. However the experiments reported here show that the internal regions of composites are very poorly matched against the faces they purport to represent, while external feature regions alone were matched almost as well as complete composites. In Experiments 1 and 2 the composites used were constructed by participant-witnesses who were unfamiliar with the targets and therefore were predicted to demonstrate a bias towards the external parts of a face. In Experiment 3 we compared witnesses who were familiar or unfamiliar with the target items, but for both groups the external features were much better reproduced in the composites, suggesting it is the process of composite construction itself which is responsible for the poverty of the internal features. Practical implications of these results are discussed.

Potential of atmospheric pressure chemical ionization source in GC-QTOF MS for pesticide residue analysis

The potential applications of a new atmospheric pressure source for GC-MS analysis have been investigated in this work. A list of around 100 GC-amenable pesticides, which includes organochlorine, organophosphorus and organonitrogenated compounds, has been used to evaluate their behavior in the new source. Favoring the major formation of the molecular ion in the source has been the main goal due to the wide-scope screening possibilities that this fact brings in comparison with the traditional, highly fragmented electron ionization spectra. Thus, the addition of water as modifier has been tested as a way to promote the generation of protonated molecules. Pesticides investigated have been classified into six groups according to their ionization/fragmentation behavior. Four of them are characterized by the abundant formation of the protonated molecule in the atmospheric pressure source, mostly being the base peak of the spectrum. These results show that wide-scope screening could be easily performed with this source by investigating the presence of the protonated molecule ion, MH+. The developed procedure has been applied to pesticide screening in different food samples (nectarine, orange and spinach) and it has allowed the presence of several pesticides to be confirmed such as chlorpyriphos ethyl, deltamethrin and endosulfan sulfate. The availability of a quadrupole time-of-flight instrument made it feasible to perform additional MS/MS experiments for both standards and samples to go further in the confirmation of the identity of the detected compounds. Results shown in this paper have been obtained using a prototype source which exhibits promising features that could be applied to other analytical problems apart from those illustrated in this work.

The Relationship Between Two Measures of Self-Actualization

The Personal Orientation Dimensions have been introduced as a refinement and extension of concepts of self-actualizing first measured by the Personal Orientation Inventory. The two inventories are theoretically and empirically compared and contrasted. Overall, there is little to favor the POD. It adds little, if anything, to what the POI provides. The recommendation is that users keep using the POI and not use the POD.

Co-Location of Services for Refugees: An Evaluation of a Pilot Program in Western Australia

In recent years newly arrived refugees from Africa, Burma and Middle Eastern nations have dominated the refugee intake to Australia. Coming from war torn nations, extremely poor economies and rural areas, their transition into Australia has not been easy. This paper is based on the evaluation of the Integrated Services Centre Pilot Project (ISC) which assessed co-location as an alternative service delivery model. The evaluation focused on project staff, service providers and a small sample of the refugees themselves. The objectives of the research did not warrant a greater focus on the clients as the evaluation centered on co-location as an alternate service delivery model. Data gathered from the evaluation indicated that the basic support needs of African refugees were not being met by traditional refugee services, but that the ISC Project was meeting these needs. Data also showed that African refugees had a higher level of need than other refugee groups. The article concludes with some recommendations on how current service provision can be more responsive to the needs of African refugees.

Diagnostic utility of the Pittsburgh Sleep Quality Index in memory clinics

BACKGROUND

Since sleep is important for physiological memory function, sleep disturbance may contribute to subjective memory complaints and objective memory impairments independent of brain pathology. We investigated the diagnostic utility of the Pittsburgh Sleep Quality Index (PSQI) as an independent test to differentiate patients with and without dementia at the initial clinical diagnostic interview in dedicated memory clinics.

METHODS

PSQI was administered to consecutive new patient referrals to two memory clinics over a 2-year period, independent of other tests (interview, neuropsychology, imaging) which were used to establish diagnoses according to standard diagnostic criteria (DSM-IV), and results were compared.

RESULTS

In a cohort of 310 patients, 50% fulfilling clinical diagnostic criteria for dementia, PSQI scores and subscores showed suboptimal sensitivity, specificity, positive and negative predictive values (PPV, NPV) and area under the Receiver Operating Characteristic (ROC) curve for the diagnosis of dementia, and likelihood ratios were unimportant. However, the proportion of poor sleepers was significantly larger in the non-demented as compared to the demented patient group.

CONCLUSIONS

PSQI scores were suboptimal for dementia diagnosis using traditional diagnostic parameters, but were pragmatically useful in identifying non-demented 'memory complainers' with poor sleep quality. This observation may have therapeutic implications for these patients.

Evaluation of the Integrated Services Pilot Program from Western Australia

Independent evaluation of refugee-focused programs in developed nations is increasingly a mandatory requirement of funding bodies and government agencies. This paper presents an evaluation of the Integrated Services Centre (ISC) Pilot Project that was conducted in Australia in 2007 and early 2008. The purpose of the ISC program was to provide integrated support to humanitarian refugees in settlement, physical health, mental health and employment. The Pilot Project was based in two primary schools in Perth, Western Australia. The evaluation utilized a flexible qualitative 'engaged' methodology and included interviews, focus groups and telephone interviews with the key stakeholders, project staff and a small number of refugee families. The strength of the qualitative methodology (including data that is narrative rich) is that it highlights issues as perceived by each stakeholder and provides insights into the daily work by ISC staff that helped to uncover unintended outcomes. Despite the fact that the ISC evaluation was supposed to be a 'before and after' design, the researchers acknowledge a common weakness in many evaluations (including the ISC) that when baseline data is required, evaluators are recruited after the project has begun. This issue is discussed in the paper. It is critical that independent evaluators are able to begin collecting baseline data as soon as programs are launched, if not before.

Clinical utility of Patient Health Questionnaire-9 (PHQ-9) in memory clinics

Background. Both dementia and depression may produce complaints of memory impairment. Differential diagnosis may be difficult, but has practical implications regarding choice of appropriate treatment. Aim. To assess the clinical utility of the Patient Health Questionnaire-9 (PHQ-9), a validated instrument for measurement of depression severity, in differentiating patients with and without dementia, referred with complaints of memory impairment to dedicated memory clinics. Methods. Pragmatic prospective study of consecutive referrals (n=113) to two dementia clinics, diagnosed using standard clinical diagnostic criteria for dementia (DSM-IV) and also administered the PHQ-9. Results. PHQ-9 proved acceptable to patients, and was quick and easy to use. Using traditional parameters of diagnostic utility (sensitivity, specificity, positive predictive value, likelihood ratios), PHQ-9 performance was modest for the diagnosis of dementia. However, pragmatically PHQ-9 scores proved helpful in deciding which patients, both with and without dementia, required a trial of antidepressant medication. Conclusions. PHQ-9 proved useful as a brief screen for depression in patients attending dementia clinics with a complaint of memory impairment.

Effects of warned and unwarned demand transitions on vigilance performance and stress

The present study was designed to explore the effects of warned and unwarned demand transitions in vigilance on performance and self-reported stress. Twenty observers (10 women and 10 men) were assigned at random to each of six conditions resulting from the factorial combination of signal salience (high and low salience signals) and switching (no switch, switch with warning, and switch without warning). Performance metrics and self-reported stress state (Task Engagement, Distress, and Worry) were collected. While demand transitions did destabilize subsequent performance, increasing intra-individual variability, overall performance efficiency was uninfluenced by either switching or warning. Demand transitions, whether warned or not, increased self-reported distress. A dynamic model of performance stress may be necessary and research employing vigilance tasks in the future may be useful for developing this performance-stress model.

Analysis of biologically active compounds in water by ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry

A new method based on ultra-performance liquid chromatography (UPLC) quadrupole time-of-flight mass spectrometry ((Q-ToF)-MS) was developed for the analysis of 32 biologically active compounds including anti-inflammatories, analgesics, lipid regulators, psychiatric drugs, anti-ulcer agents, antibiotics, beta-blockers and phytoestrogens. This new method allows chromatographic analysis in 14 min, with instrumental detection limits from 2 to 84 pg, and limits of quantification ranging from 0.1 to 15 ng/L in tap water, and from 2 to 300 ng/L in wastewater. The potential of liquid chromatography with triple quadrupole mass spectrometry (LC/QqQ-MS) was compared with that of UPLC/(Q-ToF)-MS for the analysis of biologically active compounds in water samples. LC/Q-ToF provides accurate mass information and a significantly higher mass resolution than quadrupole analyzers. The available mass resolution of ToF instruments diminishes the problem of isobaric interferences and helps the analysis of trace compounds in complex samples. In this work UPLC/Q-ToF chromatograms were recorded containing full scan spectral data. The m/z values of analytes were extracted from the total ion chromatogram (TIC) and the accurate masses of the compounds were obtained. In addition, to increase the selectivity of ToF measurements a narrow accurate mass interval (20 m m/z units mass window) was used to reconstruct the chromatographic traces. However, regarding quantitative performance in terms of dynamic range and limits of detection (LODs), typical LODs achieved by QqQ instruments operating in multiple-reaction monitoring (MRM) mode ranged from 1 to 50 ng/L in wastewater, and the linear response for QqQ instruments generally covers three orders of magnitude. This is an important advantage over ToF instruments and one of the reasons why QqQ instruments are widely used in quantitative environmental analysis.

Quantification and screening of pesticide residues in food by gas chromatography–exact mass time-of-flight mass spectrometry

A gas chromatography-exact mass time-of-flight mass spectrometry (GC-TOF-MS) method has been developed for the quantification of approximately one hundred pesticides in baby food, pear and lettuce samples. Prior to analysis, co-extractives were removed from acetonitrile:toluene (80:20) extracts using dispersive solid-phase extraction with primary secondary amine (50mg) and carbon sorbent (50mg). The concentration of pesticides in the extracts was measured using an extracted mass chromatogram window of 0.05 Th. Samples spiked with pesticides at 0.01 and 0.1 mgkg(-1) yielded average recoveries in the range of 70-109% with relative standard deviations less than 26% and displayed good linearity for the majority of the analytes. The method was applied to the screening of pear and lettuce samples for pesticide residues. Targeted quantification and exact mass peak detection, deconvolution and library searching packages were used successfully to detect and identify incurred residues present in the samples at concentrations above 0.01 mgkg(-1). The new feature dynamic range enhancement, improved mass accuracy, and hence detection and quantification of the analytes across the concentration range studied.

The diagnosis of dementia: diagnostic accuracy of an instrument measuring activities of daily living in a clinic-based population

BACKGROUND/AIMS

Since widely accepted definitions of dementia encompass impairments in social and occupational, as well as cognitive, function, we investigated the diagnostic accuracy of Lawton and Brody's Instrumental Activities of Daily Living (IADL) Scale as an independent test for the diagnosis of dementia.

METHODS

The IADL Scale was administered to consecutive referrals to 2 memory clinics over a 2-year period, independent of other tests (interview, neuropsychology, imaging) which were used to establish diagnoses according to standard diagnostic criteria, and the results were compared.

RESULTS

In a cohort of 296 patients, 52% adjudged to have dementia, IADL Scale scores and subscores showed low sensitivity, specificity, and positive and negative predictive values for the diagnosis of dementia. The likelihood ratios, a measure of diagnostic gain, were generally small to unimportant, and diagnostic accuracy as measured by area under the receiver operating characteristic curve was no better than 0.75.

CONCLUSION

IADL Scale scores are not very helpful in making a diagnosis of dementia. More sensitive scales may be required to detect dementia-related functional decline, although it is also possible that dementia syndromes may be present in the absence of functional decline, challenging accepted definitions of dementia.

Ultra-performance liquid chromatography for the determination of pesticide residues in foods by tandem quadrupole mass spectrometry with polarity switching

An ultra-performance liquid chromatographic (UPLC) electrospray ionisation tandem quadrupole mass spectrometric method has been developed for the determination of 52 pesticides in cereal-based baby foods, oranges and potatoes. The fast polarity switching capability of the mass spectrometer used enabled the determination of 44 of the compounds in the positive ionisation mode and 8 of the compounds in the negative ionisation mode in a single run. Prior to analysis, co-extractives were removed from acetonitrile extracts using dispersive solid-phase extraction with primary secondary amine (50 mg). The UPLC method separates all of the pesticides, resolves structural isomers (e.g. butocarboxim sulfoxide and aldicarb sulfoxide) and has a short (7 min) cycle time. Extracts spiked with pesticides at 0.10 and 0.01 mg kg(-1) yielded average recoveries in the range of 66-124% with relative standard deviations less than 19% for the majority of the analytes.

Comparison of ultra-performance liquid chromatography and high-performance liquid chromatography for the determination of priority pesticides in baby foods by tandem quadrupole mass spectrometry

Determination of 16 priority pesticides and transformation products specified in the EU Baby Food Directive 2003/13/EC has been compared using high-performance liquid chromatography (HPLC) and ultra-performance liquid chromatography (UPLC) coupled to tandem quadrupole mass spectrometry (MS/MS). Prior to analysis, co-extractives were removed from acetonitrile extracts using dispersive solid-phase extraction (SPE) with primary secondary amine (50 mg). Extracts spiked with pesticides at 1 microg kg(-1) yielded average recoveries in the range 85-119%, with relative standard deviations less than 17%. The HPLC-MS/MS and UPLC-MS/MS multi-residue methods developed are simple, rapid and suitable for the quantification and confirmation of the 16 priority pesticides in fruit-, potato- and cereal-based baby food at 1 microg kg(-1). The major advantages of UPLC, using 1.7 microm particles, over HPLC are the speed of analysis, the narrower peaks (giving increased signal-to-noise ratio) and improved confirmation for the targeted pesticides in the analyses of baby foods.

Monozygotic Twins' Colour-Number Association: a Case Study

A case study of a pair of monozygotic twins, both of whom show a strong and enduring colour-number association, is reported. The origin of the colours, in a jigsaw puzzle, is known. Neither reports conscious photisms typical of synaesthesia, but a Stroop task of naming the colours of digits shows an interference effect with incongruent colours.

The enigma of facial asymmetry: is there a gender-specific pattern of facedness?

Although facial symmetry correlates with facial attractiveness, human faces are often far from symmetrical with one side frequently being larger than the other (Kowner, 1998). Smith (2000) reported that male and female faces were asymmetrical in opposite directions, with males having a larger area on the left side compared to the right side, and females having a larger right side compared to the left side. The present study attempted to replicate and extend this finding. Two databases of facial images from Stirling and St Andrews Universities, consisting of 180 and 122 faces respectively, and a third set of 62 faces collected at Abertay University, were used to examine Smith's findings. Smith's unique method of calculating the size of each hemiface was applied to each set. For the Stirling and St Andrews sets a computer program did this automatically and for the Abertay set it was done manually. No significant overall effect of gender on facial area asymmetry was found. However, the St Andrews sample demonstrated a similar effect to that found by Smith, with females having a significantly larger mean area of right hemiface and males having a larger left hemiface. In addition, for the Abertay faces handedness had a significant effect on facial asymmetry with right-handers having a larger left side of the face. These findings give limited support for Smith's results but also suggest that finding such an asymmetry may depend on some as yet unidentified factors inherent in some methods of image collection.