Reliability Of Metrics Research Articles

Assessing metacognitive knowledge in subjective decisions: The knowledge of weights paradigm

Subjective, multi-attribute choice decisions – such as whom to marry or which college to attend – play a substantial role in decision makers’ long-term well-being. However, the metacognition literature lacks tools for assessing metacognitive capacities in subjective decisions. We present three studies in which we propose and validate the Knowledge of Weights (KoW) paradigm, a novel method for assessing metacognitive knowledge of attribute weights in subjective, multi-attribute choice decisions. In Study 1, we demonstrate the test-retest reliability of metrics generated by the KoW paradigm. In Study 2, we apply the KoW paradigm in four domains and show that it generates consistent results. In Study 3, we demonstrate that participants who perform better on the KoW paradigm make choices with which they are more satisfied, providing suggestive evidence of predictive validity. Use cases in cognitive psychology and beyond are discussed.

Establishing the reliability of metrics extracted from long-form recordings using LENA and the ACLEW pipeline.

Long-form audio recordings are increasingly used to study individual variation, group differences, and many other topics in theoretical and applied fields of developmental science, particularly for the description of children's language input (typically speech from adults) and children's language output (ranging from babble to sentences). The proprietary LENA software has been available for over a decade, and with it, users have come to rely on derived metrics like adult word count (AWC) and child vocalization counts (CVC), which have also more recently been derived using an open-source alternative, the ACLEW pipeline. Yet, there is relatively little work assessing the reliability of long-form metrics in terms of the stability of individual differences across time. Filling this gap, we analyzed eight spoken-language datasets: four from North American English-learning infants, and one each from British English-, French-, American English-/Spanish-, and Quechua-/Spanish-learning infants. The audio data were analyzed using two types of processing software: LENA and the ACLEW open-source pipeline. When all corpora were included, we found relatively low to moderate reliability (across multiple recordings, intraclass correlation coefficient attributed to the child identity [Child ICC], was < 50% for most metrics). There were few differences between the two pipelines. Exploratory analyses suggested some differences as a function of child age and corpora. These findings suggest that, while reliability is likely sufficient for various group-level analyses, caution is needed when using either LENA or ACLEW tools to study individual variation. We also encourage improvement of extant tools, specifically targeting accurate measurement of individual variation.

Towards net-zero embodied carbon: Investigating the potential for ambitious embodied carbon reductions in Australian office buildings

Embodied carbon is recognised as a major contributor to building-related greenhouse gas (GHG) emissions. In response, ambitious targets have been posed to reduce embodied carbon in the built environment, including the aspiration of ‘net-zero embodied carbon’. This research uses a life cycle assessment (LCA) methodology to explore the magnitude of embodied carbon reductions viable within a multi-storey office building in Australia. It compares a typical building with more ambitious design scenarios to determine if net-zero embodied carbon is feasible in the current context and how design, material and methological decisions impact this. The results show that upfront embodied carbon reductions of 17–45% are achieveable with ambitious design and material changes, including a full timber structure, hybrid timber-aluminium façade, reduced columns grids, straw insulation, and more. However, the magnitude of reductions is highly influenced by material data sources and methodology. Net-zero embodied carbon was achievable when considering biogenic emissions stored in timber and other biomaterials, although only temporarily, for a period of up to 19 years. In response, we propose a new term ‘temporal net-zero embodied carbon’ to identify the point in time during a building's life cycle when it can no longer be considered a temporary carbon sink. The paper concludes by highlighting the opportunties and challenges temporal net-zero embodied carbon presents in terms of transparency and reliability of metrics, the need for consistent approaches to measurement and benchmarking, and the challenges of achieving large-scale embodied carbon reductions in the office sector.

Reliability of a TMS-derived threshold matrix of corticomotor function.

Transcranial magnetic stimulation (TMS) studies typically focus on suprathreshold motor evoked potentials (MEPs), overlooking small MEPs representing subthreshold corticomotor pathway activation. Assessing subthreshold excitability could provide insights into corticomotor pathway integrity and function, particularly in neurological conditions like stroke. The aim of the study wasto examine the test-retest reliability of metrics derived from a novel compositional analysis of MEP data from older adults. The study also compared the composition between the dominant (D) and non-dominant (ND) sides and explored the association between subthreshold responses and resting motor threshold. In this proof-of-concept study, 23 healthy older adults participated in two identical experimental sessions. Stimulus-response (S-R) curves and threshold matrices were constructed using single-pulse TMS across intensities to obtain MEPs in four upper limb muscles. S-R curves had reliable slopes for every muscle (Intraclass Correlation Coefficient range = 0.58-0.88). Subliminal and suprathreshold elements of the threshold matrix showed good-excellent reliability (D subliminal ICC = 0.83; ND subliminal ICC = 0.79; D suprathreshold ICC = 0.92; ND suprathreshold ICC = 0.94). By contrast, subthreshold elements of the matrix showed poor reliability, presumably due to a floor effect (D subthreshold ICC = 0.39; ND subthreshold ICC = 0.05). No composition differences were found between D and ND sides (suprathreshold BF01 = 3.85; subthreshold BF01 = 1.68; subliminal BF01 = 3.49). The threshold matrix reliably assesses subliminal and suprathreshold MEPs in older adults. Further studies are warranted to evaluate the utility of compositional analyses for assessing recovery of corticomotor pathway function after neurological injury.

Quantifying Turning Tasks With Wearable Sensors: A Reliability Assessment.

The aim of this study was to establish the test-retest reliability of metrics obtained from wearable inertial sensors that reflect turning performance during tasks designed to imitate various turns in daily activity. Seventy-one adults who were healthy completed 3 turning tasks: a 1-minute walk along a 6-m walkway, a modified Illinois Agility Test (mIAT), and a complex turning course (CTC). Peak axial turning and rotational velocity (yaw angular velocity) were extracted from wearable inertial sensors on the head, trunk, and lumbar spine. Intraclass correlation coefficients (ICCs) were established to assess the test-retest reliability of average peak turning speed for each task. Lap time was collected for reliability analysis as well. Turning speed across all tasks demonstrated good to excellent reliability, with the highest reliability noted for the CTC (45-degree turns: ICC= 0.73-0.81; 90-degree turns: ICC = 0.71-0.83; and 135-degree turns: ICC = 0.72-0.80). The reliability of turning speed during 180-degree turns from the 1-minute walk was consistent across all body segments (ICC = 0.74-0.76). mIAT reliability ranged from fair to excellent (end turns: ICC = 0.52-0.72; mid turns: ICC = 0.50-0.56; and slalom turns: ICC = 0.66-0.84). The CTC average lap time demonstrated good test-retest reliability (ICC = 0.69), and the mIAT average lap time test-retest reliability was excellent (ICC = 0.91). Turning speed measured by inertial sensors is a reliable outcome across a variety of ecologically valid turning tasks that can be easily tested in a clinical environment. Turning performance is a reliable and important measure that should be included in clinical assessments and clinical trials.

Introducing value-based healthcare perspectives into hospital performance assessment: A scoping review.

Value-based healthcare (VBHC) puts patient outcomes at the center of the healthcare process while optimizing the use of hospital resources across multiple stakeholders. This scoping review was conducted to summarize how VBHC had been represented in theory and in practice, how it had been applied to assess hospital performance, and how well it had been ultimately implemented. For this review, we followed the PRISMA-ScR protocol and searched five major online databases for articles published between January 2006 and July 2022. We included original articles that used the concept of VBHC to conduct performance assessments of healthcare organizations. We extracted and analyzed key concepts and information on the dimensions of VBHC, specific strategies and methods for using VBHC in performance assessment, and the effectiveness of the assessment. We identified 48 eligible studies from 7866 articles. Nineteen nonempirical studies focused on the development of a VBHC performance assessment indicator system, and 29 empirical studies reported on the ways and points of introducing VBHC into performance assessment and its effectiveness. Ultimately, we summarized the key dimensions, processes, and effects of performance assessment after introducing VBHC. Current healthcare performance assessment has begun to focus on implementing VBHC as an integrated strategy, and future work should further clarify the reliability of metrics and their association with evaluation outcomes and consider the effective integration of clinical outcomes and patient-reported outcomes.

The effect of general anesthesia on the test-retest reliability of resting-state fMRI metrics and optimization of scan length.

Resting-state functional magnetic resonance imaging (rs-fMRI) has been known as a powerful tool in neuroscience. However, exploring the test–retest reliability of the metrics derived from the rs-fMRI BOLD signal is essential, particularly in the studies of patients with neurological disorders. Here, two factors, namely, the effect of anesthesia and scan length, have been estimated on the reliability of rs-fMRI measurements. A total of nine patients with drug-resistant epilepsy (DRE) requiring interstitial thermal therapy (LITT) were scanned in two states. The first scan was performed in an awake state before surgery on the same patient. The second scan was performed 2 weeks later under general anesthesia necessary for LITT surgery. At each state, two rs-fMRI sessions were obtained that each one lasted 15 min, and the effect of scan length was evaluated. Voxel-wise rs-fMRI metrics, including the amplitude of low-frequency fluctuation (ALFF), the fractional amplitude of low-frequency fluctuation (fALFF), functional connectivity (FC), and regional homogeneity (ReHo), were measured. Intraclass correlation coefficient (ICC) was calculated to estimate the reliability of the measurements in two states of awake and under anesthesia. Overall, it appeared that the reliability of rs-fMRI metrics improved under anesthesia. From the 15-min data, we found mean ICC values in awake state including 0.81, 0.51, 0.65, and 0.84 for ALFF, fALFF, FC, and ReHo, respectively, as well as 0.80, 0.59, 0.83, and 0.88 for ALFF, fALFF, FC, and ReHo, respectively, under anesthesia. Additionally, our findings revealed that reliability increases as the function of scan length. We showed that the optimized scan length to achieve less variability of rs-fMRI measurements was 3.1–7.5 min shorter in an anesthetized, compared to a wakeful state.

Metrics and epistemic injustice

PurposeThis paper examines the socio-political affordances of metrics in research evaluation and the consequences of epistemic injustice in research practices and recorded knowledge.Design/methodology/approachFirst, the use of metrics is examined as a mechanism that promotes competition and social acceleration. Second, it is argued that the use of metrics in a competitive research culture reproduces systemic inequalities and leads to epistemic injustice. The conceptual analysis draws on works of Hartmut Rosa and Miranda Fricker, amongst others.FindingsThe use of metrics is largely driven by competition such as university rankings and league tables. Not only that metrics are not designed to enrich academic and research culture, they also suppress the visibility and credibility of works by minorities. As such, metrics perpetuate epistemic injustice in knowledge practices; at the same time, the reliability of metrics for bibliometric and scientometric studies is put into question.Social implicationsAs metrics leverage who can speak and who will be heard, epistemic injustice is reflected in recorded knowledge and what we consider to be information.Originality/valueThis paper contributes to the discussion of metrics beyond bibliometric studies and research evaluation. It argues that metrics-induced competition is antithetical to equality and diversity in research practices.

Human well-being and natural capital indicators for Great Lakes waterfront revitalization

Revitalization of natural capital amenities at the Great Lakes waterfront can result from sediment remediation, habitat restoration, climate resilience projects, brownfield reuse, economic redevelopment and other efforts. Practical indicators are needed to assess the cultural, health, and socioeconomic benefits of these investments. We compiled U.S. census-tract scale data for five Great Lakes communities: Duluth/Superior, Green Bay, Milwaukee, Chicago, and Cleveland. We downloaded data from the US Census Bureau, Centers for Disease Control and Prevention, Environmental Protection Agency, National Oceanic and Atmospheric Administration, and non-governmental organizations. We compiled a final set of 19 human well-being (HWB) metrics and 26 metrics representing attributes of natural and seminatural amenities (natural capital). We rated the reliability of metrics according to their consistency of correlations with metrics of the other type (HWB vs. natural capital) at the census-tract scale, how often they were correlated in the expected direction, strength of correlations, and other attributes. Among the highest rated HWB indicators were measures of mean health, mental health, home ownership, home value, life success, and educational attainment. Highest rated natural capital metrics included tree cover and impervious surface metrics, walkability, density of recreational amenities, and shoreline type. Two sociodemographic covariates, household income and population density, had a strong influence on the strength of associations between HWB and natural capital and must be included in any assessment of change in HWB benefits at the waterfront. Our findings are a starting point for applying already available HWB and natural capital indicators in a waterfront revitalization context.

Facing the volatility of tweets in altmetric research

AbstractThe data re‐collection for tweets from data snapshots is a common methodological step in Twitter‐based research. Understanding better the volatility of tweets over time is important for validating the reliability of metrics based on Twitter data. We tracked a set of 37,918 original scholarly tweets mentioning COVID‐19‐related research daily for 56 days and captured the reasons for the changes in their availability over time. Results show that the proportion of unavailable tweets increased from 1.6 to 2.6% in the time window observed. Of the 1,323 tweets that became unavailable at some point in the period observed, 30.5% became available again afterwards. “Revived” tweets resulted mainly from the unprotecting, reactivating, or unsuspending of users' accounts. Our findings highlight the importance of noting this dynamic nature of Twitter data in altmetric research and testify to the challenges that this poses for the retrieval, processing, and interpretation of Twitter data about scientific papers.

Common Vertical Jump and Reactive Strength Index Measuring Devices: A Validity and Reliability Analysis.

Montalvo, S, Gonzalez, MP, Dietze-Hermosa, M, Eggleston, JD, and Dorgo, S. Common vertical jump and reactive strength index measuring devices: A validity and reliability analysis. J Strength Cond Res 35(5): 1234-1243, 2021-Several field-test devices exist to assess vertical jump, but they either lack proper validation or have been validated for the countermovement jump (CMJ) only. This study aimed to quantify the validity and reliability of metrics, including jump height and the calculated reactive strength index (RSI), obtained using the flight-time method from 4 different assessment devices with 3 different vertical jump modalities in comparison to a force platform (criterion assessment). The Optojump, Push-Band 2.0, MyJump2 mobile application, and What'sMyVert mobile application were used synchronously and together with the force platforms. Thirty subjects (17 males and 13 females; age ± SD: 23.37 ± 1.87 years) performed 5 repetitions of CMJ, squat jump (SQJ), and drop jump (DJ) with a standardized 90° knee flexion for all jumps. Relative reliability was determined by intraclass correlation (ICC) and absolute reliability by coefficient of variation (CV) analyses. Excellent reliability was considered as ICC > 0.9 and CV < 10%. Validity was obtained through an ordinary least products regression, ICC, and CV. Significance was set at p < 0.05. Reliability was excellent on jump height for the CMJ (ICC ≥ 0.98; CV ≤ 8.14%) for all instruments. With the exception of the Optojump, all instruments also had excellent reliability for the SQJ (ICC ≥ 0.98; CV ≤ 6.62) and DJ (ICC ≥ 0.94; CV ≤ 8.19). For the RSI metric, all instruments had excellent relative reliability (ICC ≥ 0.92), but none had excellent absolute reliability (CV ≥ 12.5%). The MyJump2 and What'sMyVert apps showed excellent validity on all jump modalities and RSI. The Optojump and Push-Band 2.0 devices both showed system and proportional bias for several jump modalities and RSI. Overall, both mobile applications may provide coaches with a cost-effective and reliable measurement of various vertical jumps.

Validity and reliability of metrics for translation of regional anaesthesia performance from cadavers to patients

BackgroundOur goal is to develop metrics that quantify the translation of performance from cadavers to patients. Our primary objective was to develop steps and error checklists from a Delphi questionnaire. Our second objective was to show that our test scores were valid and reliable. MethodsSixteen UK experts identified 15 steps conducive to good performance and 15 errors to be avoided during interscalene block on the soft-embalmed cadaver and patients. Thereafter, six experts and six novices were trained, and then tested. Training consisted of psychometric assessment, an anatomy tutorial, volunteer scanning, and ultrasound-guided needle insertion on a pork phantom and on a soft-embalmed cadaver. For testing, participants conducted a single interscalene block on a dedicated soft-embalmed cadaver whilst wearing eye tracking glasses. ResultsWe developed a 15-step checklist and a 15-error checklist. The internal consistency of our steps measures were 0.83 (95% confidence interval [CI]: 0.78–0.89) and 0.90 (95% CI: 0.87–0.93) for our error measures. The experts completed more steps (mean difference: 3.2 [95% CI: 1.5–4.8]; P<0.001), had less errors (mean difference: 4.9 [95% CI: 3.5–6.3]; P<0.001), had better global rating scores (mean difference: 6.8 [95% CI: 3.6–10.0]; P<0.001), and more eye-gaze fixations (median of differences: 128 [95% CI: 0–288]; P=0.048). Fixation count correlated negatively with steps (r=–0.60; P=0.04) and with errors (r=0.64; P=0.03). ConclusionsOur tests to quantify ultrasound-guided interscalene nerve block training and performance were valid and reliable.

Development and reliability of metrics to characterize types and sources of stigma among men who have sex with men and female sex workers in Togo and Burkina Faso

BackgroundStigma is a multifaceted concept that potentiates Human Immunodeficiency Virus and sexually transmitted infection acquisition and transmission risks among key populations, including men who have sex with men (MSM) and female sex workers (FSW). Despite extensive stigma literature, limited research has characterized the types and sources of stigma reported by key populations in Sub-Saharan Africa.MethodsThis study leveraged data collected from 1356 MSM and 1383 FSW in Togo and Burkina Faso, recruited via respondent-driven sampling. Participants completed a survey instrument including stigma items developed through systematic reviews and synthesis of existing metrics. Using exploratory factor analysis with promax oblique rotation, 16 items were retained in a stigma metric for MSM and 20 in an FSW stigma metric. To assess the measures’ convergent validity, their correlations with expected variables were examined through bivariate logistic regression models.ResultsOne factor, experienced stigma, included actions that were carried out by multiple types of perpetrators and included being arrested, verbally harassed, blackmailed, physically abused, tortured, or forced to have sex. Other factors were differentiated by source of stigma including healthcare workers, family and friends, or police. Specifically, stigma from healthcare workers loaded on two factors: experienced healthcare stigma included being denied care, not treated well, or gossiped about by healthcare workers and anticipated healthcare stigma included fear of or avoiding seeking healthcare. Stigma from family and friends included feeling excluded from family gatherings, gossiped about by family, or rejected by friends. Stigma from police included being refused police protection and items related to police confiscation of condoms. The Cronbach’s alpha ranged from 0.71–0.82. Median stigma scores, created for each participant by summing the number of affirmative responses to each stigma item, among MSM were highest in Ouagadougou and among FSW were highest in both Ouagadougou and Bobo-Dioulasso. Validation analyses demonstrated higher stigma was generally significantly associated with suicidal ideation, disclosure of involvement in sex work or same-sex practices, and involvement in organizations for MSM or FSW.ConclusionsTaken together, these data suggest promising reliability and validity of metrics for measuring stigma affecting MSM and FSW in multiple urban centers across West Africa.

Reliability of Static and Dynamic Network Metrics in the Resting-State: A MEG-Beamformed Connectivity Analysis.

The resting activity of the brain can be described by so-called intrinsic connectivity networks (ICNs), which consist of spatially and temporally distributed, but functionally connected, nodes. The coordinated activity of the resting state can be explored via magnetoencephalography (MEG) by studying frequency-dependent functional brain networks at the source level. Although many algorithms for the analysis of brain connectivity have been proposed, the reliability of network metrics derived from both static and dynamic functional connectivity is still unknown. This is a particular problem for studies of associations between ICN metrics and personality variables or other traits, and for studies of differences between patient and control groups, which both depend critically on the reliability of the metrics used. A detailed investigation of the reliability of metrics derived from resting-state MEG repeat scans is therefore a prerequisite for the development of connectomic biomarkers. Here, we first estimated both static (SFC) and dynamic functional connectivity (DFC) after beamforming source reconstruction using the imaginary part of the phase locking index (iPLV) and the correlation of the amplitude envelope (CorEnv). Using our approach, functional network microstates (FCμstates) were derived from the DFC and chronnectomics were computed from the evolution of FCμstates across experimental time. In both temporal scales, the reliability of network metrics (SFC), the FCμstates and the related chronnectomics were evaluated for every frequency band. Chronnectomic statistics and FCμstates were generally more reliable than node-wise static network metrics. CorEnv-based network metrics were more reproducible at the static approach. The reliability of chronnectomics have been evaluated also in a second dataset. This study encourages the analysis of MEG resting-state via DFC.

Test-retest Reliability of Functional Connectivity and Graph Metrics in the Resting Brain Network.

The combination of graph theoretical approaches and neuroimaging data provides a powerful way to explore the characteristics of brain network. Recently, the temporal variability of spontaneous brain activity and functional connectivity has attracted wide attention. Thus, it is essential to evaluate the reliability of functional network connectivity and properties from the dynamic perspective. However, previous test-retest (TRT) studies have explored this reliability with a static point of view. In this study, using a large rs-fMRI dataset from Human Connectome Project (HCP), we investigated TRT reliability of functional connectivity and graph metrics derived from the most commonly used method- sliding window at three time intervals (short: 72 seconds, middle: 15 minutes and long: >24 hours). The results revealed that reliable connectivities and related brain regions are mainly distributed in primary cortex, such as visual area and sensorimotor area and default mode network. Notably, connectivity strength and global efficiency have better reliability than other metrics. Finally, short scan time interval and long scan duration can increase the TRT reliability of metrics. Findings of present study provide important guidance for searching reliable network markers in future research.

Inter-rater Reliability for Metrics Scored in a Binary Fashion—Performance Assessment for an Arthroscopic Bankart Repair

To determine the inter-rater reliability (IRR) of a procedure-specific checklist scored in a binary fashion for the evaluation of surgical skill and whether it meets a minimum level of agreement (≥0.8 between 2 raters) required for high-stakes assessment. In a prospective randomized and blinded fashion, and after detailed assessment training, 10 Arthroscopy Association of North America Master/Associate Master faculty arthroscopic surgeons (in 5 pairs) with an average of 21years of surgical experience assessed the video-recorded 3-anchor arthroscopic Bankart repair performance of 44 postgraduate year 4 or 5 residents from 21 Accreditation Council for Graduate Medical Education orthopaedic residency training programs from across the United States. No paired scores of resident surgeon performance evaluated by the 5 teams of faculty assessors dropped below the 0.8 IRR level (mean= 0.93; range 0.84-0.99; standard deviation= 0.035). A comparison between the 5 assessor groups with 1 factor analysis of variance showed that there was no significant difference between the groups (P= .205). Pearson's product-moment correlation coefficient revealed a strong and statistically significant negative correlation, that is,-0.856 (P < .000), indicating that as intra-operative error rate scores increased, the IRR decreased. Arthroscopy Association of North America shoulder faculty raters from across the United States showed high levels of IRR in the assessment of an arthroscopic 3-anchor Bankart repair procedure. All paired assessments were above the 0.8 level and the mean IRR of all resident assessments was 0.93, indicating that they could be used for high-stakes decisions. With the move toward outcomes-based performance evaluation for graduate medical education, high-stakes assessments of surgical skill will require robust, reliable measurement tools that are able to withstand challenge. Surgical checklists employing metrics scored in a binary fashion meet the need and can show a high (>80%) IRR.

Understanding Progressive Multifocal Leukoencephalopathy Risk in Multiple Sclerosis Patients Treated with Immunomodulatory Therapies: A Bird's Eye View.

The increased use of newer potent immunomodulatory therapies for multiple sclerosis (MS), including natalizumab, fingolimod, and dimethyl fumarate, has expanded the patient population at risk for developing progressive multifocal leukoencephalopathy (PML). These MS therapies shift the profile of lymphocytes within the central nervous system (CNS) leading to increased anti-inflammatory subsets and decreased immunosurveillance. Similar to MS, PML is a demyelinating disease of the CNS, but it is caused by the JC virus. The manifestation of PML requires the presence of an active, genetically rearranged form of the JC virus within CNS glial cells, coupled with the loss of appropriate JC virus-specific immune responses. The reliability of metrics used to predict risk for PML could be improved if all three components, i.e., viral genetic strain, localization, and host immune function, were taken into account. Advances in our understanding of the critical lymphocyte subpopulation changes induced by these MS therapies and ability to detect viral mutation and reactivation will facilitate efforts to develop these metrics.

Reliability of metrics associated with a counter-movement jump performed on a force plate

ABSTRACTThe counter-movement jump is a consequence of maximal force, rate of force developed, and neuromuscular coordination. Thus, the counter-movement jump has been used to monitor various training adaptations. However, the smallest detectable difference of counter-movement jump metrics has yet to be established. The objective of the present study was to measure the reliability of counter-movement jump metrics, including rate of force development, flight time, time to max force, and max force. Twenty-nine male participants (mean age 25 ± 3 years) were divided into three groups. Each participant performed five counter-movement jumps on a force plate, on three consecutive days. Flight time detected trivial changes, (effect size < .2) and typical error of measurement of .25%; max force detected small changes (effect size < .5) with a typical error of measurement of .3%; rate of force development detected small to medium change (effect size .5–.8) with a typical error of measurement of .3%.

Early and late adjustments of the photosynthetic traits and stomatal density in Quercus ilex L. grown in an ozone-enriched environment.

Quercus ilex L. seedlings were exposed in open-top chambers for one growing season to three levels of ozone (O3 ): charcoal filtered air, non-filtered air supplemented with +30% or +74% ambient air O3 . Key functional parameters related to photosynthetic performance and stomatal density were measured to evaluate the response mechanisms of Q. ilex to chronic O3 exposure, clarifying how ecophysiological traits are modulated during the season in an ozone-enriched environment. Dark respiration showed an early response to O3 exposure, increasing approximately 45% relative to charcoal-filtered air in both O3 enriched treatments. However, at the end of the growing season, maximum rate of assimilation (Amax ) and stomatal conductance (gs ) showed a decline (-13% and -36%, for Amax and gs , respectively) only in plants under higher O3 levels. Photosystem I functionality supported the capacity of Q. ilex to cope with oxidative stress by adjusting the energy flow partitioning inside the photosystems. The response to O3 was also characterised by increased stomatal density in both O3 enriched treatments relative to controls. Our results suggest that in order to improve the reliability of metrics for O3 risk assessment, the seasonal changes in the response of gs and photosynthetic machinery to O3 stress should be considered.

On the reliability of rhythm metrics.

In the past decade or so, various metrics of vocalic and consonantal variability have been used to quantify linguistic rhythm, often yielding disparate results. The reliability of several such metrics (percentage of vocalic intervals and consonantal standard deviation, pairwise variability indices, and variation coefficient) was tested using materials from stress-timed English and German, syllable-timed Spanish and Italian, Korean, an unclassified language, and Greek, which has resisted classification. The materials for each language were divided into three subsets: an uncontrolled subset of sentences excerpted from a representative author of each language, a subset exhibiting as much as possible “stress-timing” properties (complex syllable structure and extensive vocalic variability), and a subset exhibiting as much as possible “syllable-timing” properties (simple syllable structure and limited vocalic variability). The results suggest that rhythmic scores can be severely affected by the choice of materials, especially in languages such as Italian, in which it is easy to avoid or accentuate variability (e.g., by excluding or including geminates). Variation coefficient scores were the most resistant to the manipulation of materials but failed to show statistical differences across most of the languages examined. The overall results cast doubt on the reliability of metric scores as indicators of timing and linguistic rhythm.