Low Temporal Stability Research Articles

Characterization of the temporal stability of ToM and pain functional brain networks carry distinct developmental signatures during naturalistic viewing

A temporally stable functional brain network pattern among coordinated brain regions is fundamental to stimulus selectivity and functional specificity during the critical period of brain development. Brain networks that are recruited in time to process internal states of others’ bodies (like hunger and pain) versus internal mental states (like beliefs, desires, and emotions) of others’ minds allow us to ask whether a quantitative characterization of the stability of these networks carries meaning during early development and constrain cognition in a specific way. Previous research provides critical insight into the early development of the theory-of-mind (ToM) network and its segregation from the Pain network throughout normal development using functional connectivity. However, a quantitative characterization of the temporal stability of ToM networks from early childhood to adulthood remains unexplored. In this work, reusing a large sample of children (n = 122, 3–12 years) and adults (n = 33) dataset that is available on the OpenfMRI database under the accession number ds000228, we addressed this question based on their fMRI data during a short and engaging naturalistic movie-watching task. The movie highlights the characters’ bodily sensations (often pain) and mental states (beliefs, desires, emotions), and is a feasible experiment for young children. Our results tracked the change in temporal stability using an unsupervised characterization of ToM and Pain networks DFC patterns using Angular and Mahalanobis distances between dominant dynamic functional connectivity subspaces. Our findings reveal that both ToM and Pain networks exhibit lower temporal stability as early as 3-years and gradually stabilize by 5-years, which continues till adolescence and late adulthood (often sharing similarity with adult DFC stability patterns). Furthermore, we find that the temporal stability of ToM brain networks is associated with the performance of participants in the false belief task to access mentalization at an early age. Interestingly, higher temporal stability is associated with the pass group, and similarly, moderate and low temporal stability are associated with the inconsistent group and the fail group. Our findings open an avenue for applying the temporal stability of large-scale functional brain networks during cortical development to act as a biomarker for multiple developmental disorders concerning impairment and discontinuity in the neural basis of social cognition.

A Multiplexed Quantitative Proteomics Approach to the Human Plasma Protein Signature.

Despite the plasma proteome being able to provide a unique insight into the health and disease status of individuals, holding singular promise as a source of protein biomarkers that could be pivotal in the context of personalized medicine, only around 100 proteins covering a few human conditions have been approved as biomarkers by the US Food and Drug Administration (FDA) so far. Mass spectrometry (MS) currently has enormous potential for high-throughput analysis in clinical research; however, plasma proteomics remains challenging mainly due to the wide dynamic range of plasma protein abundances and the time-consuming procedures required. We applied a new MS-based multiplexed proteomics workflow to quantitate proteins, encompassing 67 FDA-approved biomarkers, in >1300 human plasma samples from a clinical cohort. Our results indicate that this workflow is suitable for large-scale clinical studies, showing good accuracy and reproducibility (coefficient of variation (CV) < 20 for 90% of the proteins). Furthermore, we identified plasma signature proteins (stable in time on an individual basis), stable proteins (exhibiting low biological variability and high temporal stability), and highly variable proteins (with low temporal stability) that can be used for personalized health monitoring and medicine.

Clarifying the longitudinal factor structure, temporal stability, and construct validity of Go/No-Go task-related neural activation across adolescence and young adulthood

This study aimed to clarify the psychometric properties and development of Go/No-Go (GNG) task-related neural activation across critical periods of neurobiological maturation by examining its longitudinal stability, factor structure, developmental change, and associations with a computational index of task-general cognitive control. A longitudinal sample (N=289) of adolescents from the Michigan Longitudinal Study was assessed at four time-points (mean number of timepoints per participant=2.05; standard deviation=0.89) spanning early adolescence (ages 10−13) to young adulthood (22−25). Results suggested that regional neural activations from the “successful inhibition” (SI>GO) and “failed inhibition” (FI>GO; error-monitoring) contrasts are each described well by a single general factor. Neural activity across both contrasts showed developmental increases throughout adolescence that plateau in young adulthood. Neural activity metrics evidenced low temporal stability across this period of marked developmental change, and the SI>GO factor showed no relations with a behavioral index of cognitive control. The FI>GO factor displayed stronger criterion validity in the form of significant, positive associations with behaviorally measured cognitive control. Findings emphasize the utility of well-validated psychometric methods and longitudinal data for clarifying the measurement properties of functional neuroimaging metrics and improving measurement practices in developmental cognitive neuroscience.

On the (un)reliability of common behavioral and electrophysiological measures from the stop signal task: Measures of inhibition lack stability over time

Response inhibition, the intentional stopping of planned or initiated actions, is often considered a key facet of control, impulsivity, and self-regulation. The stop signal task is argued to be the purest inhibition task we have, and it is thus central to much work investigating the role of inhibition in areas like development and psychopathology. Most of this work quantifies stopping behavior by calculating the stop signal reaction time as a measure of individual stopping latency. Individual difference studies aiming to investigate why and how stopping latencies differ between people often do this under the assumption that the stop signal reaction time indexes a stable, dispositional trait. However, empirical support for this assumption is lacking, as common measures of inhibition and control tend to show low test-retest reliability and thus appear unstable over time. The reasons for this could be methodological, where low stability is driven by measurement noise, or substantive, where low stability is driven by a larger influence of state-like and situational factors. To investigate this, we characterized the split-half and test-retest reliability of a range of common behavioral and electrophysiological measures derived from the stop signal task. Across three independent studies, different measurement modalities, and a systematic review of the literature, we found a pattern of low temporal stability for inhibition measures and higher stability for measures of manifest behavior and non-inhibitory processing. This pattern could not be explained by measurement noise and low internal consistency. Consequently, response inhibition appears to have mostly state-like and situational determinants, and there is little support for the validity of conceptualizing common inhibition measures as reflecting stable traits.

Agreement with COVID-19 Conspiracy Theories Has Poor Temporal Stability.

Low temporal stability may complicate the interpretation of survey measures of conspiracy theories (CTs). Current study examines the stability of endorsement of CTs on a popular set of items addressing COVID-19-related CTs. An online survey tapping two CTs about COVID-19 was administered to 179 students of general medicine. The same items were presented twice in March 2022 and once in May 2022. The mean endorsement of the CTs did not differ between March and May. The correlation between answers provided in March and May was low (.5 < r < .7). Most of those reporting agreement with CTs in March reported disagreement in May. Conspiracy believers' responses did not change between two measurements in March but were different in May, suggesting that the low temporal stability was due to situational factors rather than erroneous or random answers. Poor temporal stability of responses endorsing CTs may problematize interpretation of survey data. Respondents' endorsement of CTs may be affected by situational factors, inflating agreement with CTs, and correlations with other survey-based measures.

Response of Aboveground Net Primary Production, Species and Phylogenetic Diversity to Warming and Increased Precipitation in an Alpine Meadow.

The uncertain responses of aboveground net primary productivity (ANPP) and plant diversity to climate warming and increased precipitation will limit our ability to predict changes in vegetation productivity and plant diversity under future climate change and further constrain our ability to protect biodiversity and ecosystems. A long-term experiment was conducted to explore the responses of ANPP, plant species, phylogenetic α-diversity, and community composition to warming and increased precipitation in an alpine meadow of the Northern Tibet from 2014 to 2019. Coverage, height, and species name were obtained by conventional community investigation methods, and ANPP was obtained using observed height and coverage. Open-top chambers with two different heights were used to simulate low- and high-level climate warming. The low- and high-level increased precipitation treatments were achieved by using two kinds of surface area funnel devices. The high-level warming reduced sedge ANPP (ANPPsedge) by 62.81%, species richness (SR) by 21.05%, Shannon by 13.06%, and phylogenetic diversity (PD) by 14.48%, but increased forb ANPP (ANPPforb) by 56.65% and mean nearest taxon distance (MNTD) by 33.88%. Species richness, Shannon, and PD of the high-level warming were 19.64%, 9.67%, and 14.66% lower than those of the low-level warming, respectively. The high-level warming-induced dissimilarity magnitudes of species and phylogenetic composition were greater than those caused by low-level warming. The low- rather than high-level increased precipitation altered species and phylogenetic composition. There were significant inter-annual variations of ANPP, plant species, phylogenetic α-diversity and community composition. Therefore, climate warming and increased precipitation had non-linear effects on ANPP and plant diversity, which were due to non-linear changes in temperature, water availability, and/or soil nutrition caused by warming and increased precipitation. The inter-annual variations of ANPP and plant diversity were stronger than the effects of warming and especially increased precipitation on ANPP and plant diversity. In terms of plant diversity conservation and related policy formulation, we should pay more attention to regions with greater warming, at least for the northern Tibet grasslands. Besides paying attention to the responses of ANPP and plant diversity to climate change, the large inter-annual changes of ANPP and plant diversity should be given great attention because the large inter-annual variation indicates the low temporal stability of ANPP and plant diversity and thus produces great uncertainty for the development of animal husbandry.

Interprofessional team membership stability and medical errors in emergency departments

IntroductionDelays to care and treatment in emergency departments (EDs) can lead to medical errors that harm patients. To optimize ED outcomes, indicators exist that define time frames within which patients should be assessed, receive care, and be discharged and they include time to triage, time to physician assessment (PIA), and time to discharge. The purpose of this study was to examine the relationship between temporal TMS and medical errors as delays to care in EDs. Methods: A nonexperimental, quantitative, cross-sectional, and correlational research design was used to study the relationship between differences in IP team membership due to shift work schedules (i.e., TMS) and medical errors as patient outcomes within EDs. Fifteen EDs and urgent care centres (referred collectively as EDs) located in the province of Manitoba, Canada were selected for this study. Results: medical errors occurred at each ED but to different extents; ED teams had low temporal stability; TMS and medical errors were not statistically significant, but worked experience captured by the individual team competence index (ITCI) decreased time to physician and length of stay was. TMS had a negative moderating effect on ITCI and neither TMS nor ITCI were statistically significant when patient volumes and levels of acuity were controlled. In contrast, when team size was controlled, TMS had a large effect size on time to physician. Conclusion: low TMS was not a significant factor in medical errors measured as delays to care but probably related to other organizational factors and team dynamics.

Unreliable conspiracies: survey results about COVID-19 conspiracy theories lack temporal stability

IntroductionConspiracy theories complicating public reaction to the COVID-19 pandemic inspired quantitative research on conspiracy theories, mostly using survey-based, correlational designs. Data from similar studies may, however, be unreliable due to low temporal stability (Graham, 2021).ObjectivesWe examine the temporal stability of a popular survey measure of COVID-19 conspiracy beliefs (CCBs).MethodsCCBs were measured by a popular set of items developed in the first months of the pandemic, addressing the beliefs that COVID-19 was a hoax (CCH) and that it was artificially created for evil purposes (CCC) (Imhoff &amp; Lamberty, 2020), in 179 students of medicine. In March 2022, CCBs were measured twice using the same set of questions presented once with a numeric (N1 measure) and once with a Lickertian (L1 measure) scale, with filler questions in between. The same Lickertian items were presented to the same sample in May 2022 (L2 measure).ResultsThe mean agreement with CCBs did not differ between March and May 2022 and previous survey on a similar sample in January 2021. The temporal stability of CCBs expressed as the correlation between the L1 and L2 measurement was poor (r = .57 for CCC, r = .67, for CCH). The difference between L1 and L2 was positively correlated with agreement with CCBs (r =.21, p &lt; .01 for CCH; r = .44; p &lt; .001 for CCC). Out of 18 respondents reporting agreement with CCC in March and 5 respondents reporting agreement with CCH, only 8 still reported agreement with CCC and 1 reported agreement with CCH in May.Finally, participants were split based on their L1 CCC score into groups of “mainstreamers”, “undecided”, and “conspirators”. For “mainstreamers”, there was no difference between their CCC score recorded in N1, L1, and L2. For “undecided”, there was a difference between L1 versus N1=L2, suggesting random effects (regression to the mean). For “conspirators”, the scores recorded in March were equal, while their agreement with CCC was lower in May, suggesting that the scores recorded in March were not random and the difference between March and May is better explained by situational factors.ConclusionsTemporal stability of survey-reported CCBs is low, particularly among those reporting agreement with CCBs: When a respondent reports agreement with a CCB in a survey, they are more likely to disagree than agree with the same CCB two months later. The low temporal stability seems to be affected not only by incorrect or random answers, but also by situational factors. Implications: First, survey measures of CCBs may inflate the spread of conspiracy theories in population. Second, correlations of CCBs with other variables measured by surveys may be inflated via common method bias, distorting our understanding of the predictors and consequences of CCB.Disclosure of InterestNone Declared

Semantic processing features and schizotypal traits: A test-retest study

Semantic processing abnormalities have been observed across the schizophrenia spectrum. However, it is unclear whether associations between semantic processing measures and schizotypal traits are stable over time. The current study aimed to explore the temporal stability of semantic processing measures and their correlations with schizotypal traits. In this study, we used the Schizotypal Personality Questionnaire (SPQ) to assess schizotypal traits and explored the association between schizotypal traits and semantic processing measures (i.e., N400- a large negativity with a broad scalp distribution, peaking around 400 ms after the presentation of any potentially meaningful stimulus) at baseline (Time 1; n = 63) and 3 months later (Time 2; n = 44). Repeated-measure ANOVA was conducted to examine the stability of the semantic processing measures; the intraclass correlation coefficient (ICC) was used to examine test-retest reliability; Pearson's r was calculated to explore associations between schizotypal traits and semantic processing measures. Results showed that both behavioral (reaction times) and N400 measures showed high reliability but low temporal stability. N400 latency for semantically unrelated stimuli was correlated with the cognitive-perceptual and the disorganized dimensions of schizotypal traits at Time 2. In conclusion, semantic processing measures generally showed good reliability. Schizotypal traits were correlated with N400 latencies in the current sample, but further studies are needed to examine whether this association is stable.

Can Membership Change Bring Beneficial Outcomes to Strong Faultline Teams?

Membership change is common in organization. However, extant research generally suggests that teams with low temporal stability (i.e., frequent membership change) tend to perform worse than teams with high temporal stability (i.e., stable membership), because membership change often disrupts team coordination. In this paper, we examine whether membership change can also bring beneficial outcome to strong faultline teams by ‘disrupting’ team conflict. We conduct experiment on 179 student teams and field survey on 71 organizational teams to test this idea. Our finding reveals a mixed benefit and cost of low temporal stability on strong faultline teams. Our experiment result supports that low temporal stability has beneficial effect to newly formed strong faultline teams by reducing conflict and increasing team performance growth. However, temporal stability does not moderate the effect of faultline on team conflict in our field survey. Instead, when strong faultline teams experience task conflict, such conflict would reduce team performance when temporal stability is low. While further research will be needed, our results provide some evidence that low temporal stability may sometimes reduce conflict of newly formed strong faultline teams, but may also intervene with effective conflict resolution among long-standing teams.

Clinical characterization of brief psychotic disorders triggered by the COVID-19 pandemic: a multicenter observational study.

This study aimed to characterize the clinical profile of patients with brief psychotic disorders (BPD) triggered by the psychosocial distress derived from the COVID-19 crisis. A multicenter study was conducted from March 14 to May 14, 2020 (the peak weeks of the pandemic in Europe). All consecutive patients presenting non-affective psychotic episodes with a duration of untreated psychosis of less than 1 month and whose onset was related to the COVID-19 crisis were recruited, but only those patients meeting Diagnostic Statistical Manual 5th edition (DSM-5) criteria for “BPD with marked stressors” (DSM-5 code: 298.8) during follow-up were finally included. Patients' sociodemographic and clinical characteristics were collected at baseline and summarized with descriptive statistics. During the study period, 57 individuals with short-lived psychotic episodes related to the emotional stress of the COVID-19 pandemic were identified, of whom 33 met DSM-5 criteria for “BPD with marked stressors”. The mean age was 42.33 ± 14.04 years, the gender distribution was almost the same, and the majority were rated as having good premorbid adjustment. About a quarter of the patients exhibited suicidal symptoms and almost half presented first-rank schizophrenia symptoms. None of them were COVID-19 positive, but in more than half of the cases, the topic of their psychotic features was COVID-19-related. The coronavirus pandemic is triggering a significant number of BPD cases. Their risk of suicidal behavior, their high relapse rate, and their low temporal stability make it necessary to closely monitor these patients over time.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00406-021-01256-w.

A review of common-path off-axis digital holography: towards high stable optical instrument manufacturing

Digital holography possesses the advantages of wide-field, non-contact, precise, and dynamic measurements for the complex amplitude of object waves. Today, digital holography and its derivatives have been widely applied in interferometric measurements, three-dimensional imaging, and quantitative phase imaging, demonstrating significant potential in the material science, industry, and biomedical fields, among others. However, in conventional off-axis holographic experimental setups, the object and reference beams propagate in separated paths, resulting in low temporal stability and measurement sensitivity. By designing common-path configurations where the two interference beams share the same or similar paths, environmental disturbance to the two beams can be effectively compensated. Therefore, the temporal stability of the experimental setups for hologram recording can be significantly improved for time-lapsing measurements. In this review, we categorise the common-path models as lateral shearing, point diffraction, and other types based on the different approaches to generate the reference beam. Benefiting from compact features, common-path digital holography is extremely promising for the manufacture of highly stable optical measurement and imaging instruments in the future.

1 μJ nanosecond low-coherent laser source with precise temporal shaping and spectral control

A μJ-level low-coherent pulse with dynamic and precise temporal shaping and spectral control is demonstrated. Low-coherent light delivered by a superluminescent diode is precisely shaped through a wave guide amplitude modulator driven by an arbitrary waveform generator. Utilizing a three-stage axial-alternating polarization-maintaining single-mode fiber amplifier, μJ-level low-coherent pulses with 3 ns durations and 20 nm instantaneous bandwidths at a 1 kHz repetition rate are obtained. In addition, a spectral control unit is used to adjust the spectrum shape. As a result, near flat-top, saddle-type, or other required special spectra can be produced. The low temporal coherence characteristics and output stability are characterized experimentally.

Temporal stability assessment in shear wave elasticity images validated by deep learning neural network for chronic liver disease fibrosis stage assessment.

To automatically detect and isolate areas of low and high stiffness temporal stability in shear wave elastography (SWE) image sequences and define their impact in chronic liver disease (CLD) diagnosis improvement by means of clinical examination study and deep learning algorithm employing convolutional neural networks (CNNs). Two hundred SWE image sequences from 88 healthy individuals (F0 fibrosis stage) and 112 CLD patients (46 with mild fibrosis (F1), 16 with significant fibrosis (F2), 22 with severe fibrosis (F3), and 28 with cirrhosis (F4)) were analyzed to detect temporal stiffness stability between frames. An inverse Red, Green, Blue (RGB) colormap-to-stiffness process was performed for each image sequence, followed by a wavelet transform and fuzzy c-means clustering algorithm. This resulted in a binary mask depicting areas of high and low stiffness temporal stability. The mask was then applied to the first image of the SWE sequence, and the derived, masked SWE image was used to estimate its impact in standard clinical examination and CNN classification. Regarding the impact of the masked SWE image in clinical examination, one measurement by two radiologists was performed in each SWE image and two in the corresponding masked image measuring areas with high and low stiffness temporal stability. Then, stiffness stability parameters, interobserver variability evaluation and diagnostic performance by means of ROC analysis were assessed. The masked and unmasked sets of SWE images were fed into a CNN scheme for comparison. The clinical impact evaluation study showed that the masked SWE images decreased the interobserver variability of the radiologists' measurements in the high stiffness temporal stability areas (interclass correlation coefficient (ICC)=0.92) compared to the corresponding unmasked ones (ICC=0.76). In terms of diagnostic accuracy, measurements in the high-stability areas of the masked SWE images (area-under-the-curve (AUC) ranging from 0.800 to 0.851) performed similarly to those in the unmasked SWE images (AUC ranging from 0.805 to 0.893). Regarding the measurements in the low stiffness temporal stability areas of the masked SWE images, results for interobserver variability (ICC=0.63) and diagnostic accuracy (AUC ranging from 0.622 to 0.791) were poor. Regarding the CNN classification, the masked SWE images showed improved accuracy (ranging from 82.5% to 95.5%) compared to the unmasked ones (ranging from 79.5% to 93.2%) for various CLD stage combinations. Our detection algorithm excludes unreliable areas in SWE images, reduces interobserver variability, and augments CNN's accuracy scores for many combinations of fibrosis stages.

Grain legume yields are as stable as other spring crops in long-term experiments across northern Europe

Grain legumes produce high-quality protein for food and feed, and potentially contribute to sustainable cropping systems, but they are grown on only 1.5% of European arable land. Low temporal yield stability is one of the reasons held responsible for the low proportion of grain legumes, without sufficient quantitative evidence. The objective of this study was to compare the yield stability of grain legumes with other crop species in a northern European context and accounting for the effects of scale in the analysis and the data. To avoid aggregation biases in the yield data, we used data from long-term field experiments. The experiments included grain legumes (lupin, field pea, and faba bean), other broad-leaved crops, spring, and winter cereals. Experiments were conducted in the UK, Sweden, and Germany. To compare yield stability between grain legumes and other crops, we used a scale-adjusted yield stability indicator that accounts for the yield differences between crops following Taylor’s Power Law. Here, we show that temporal yield instability of grain legumes (30%) was higher than that of autumn-sown cereals (19%), but lower than that of other spring-sown broad-leaved crops (35%), and only slightly greater than spring-sown cereals (27%). With the scale-adjusted yield stability indicator, we estimated 21% higher yield stability for grain legumes compared to a standard stability measure. These novel findings demonstrate that grain legume yields are as reliable as those of other spring-sown crops in major production systems of northern Europe, which could influence the current negative perception on grain legume cultivation. Initiatives are still needed to improve the crops agronomy to provide higher and more stable yields in future.

Soil water content and temporal stability in an arid area with natural and planted grasslands

AbstractSoil water content (SWC) is a key factor for successful vegetation restoration in arid and semiarid regions, and vegetation has significant influences on the spatial patterns and temporal dynamics of SWC. The aim of this study was to investigate the temporal stability of SWC under different restored grasslands in an arid hilly area of Central China. SWC was measured in the 0‐ to 300‐cm soil profile in the natural grassland (Stipa capillata) and three typical planted grasslands (Medicago sativa, Agropyron cristatum, and Caragana korshinskii) over two growing seasons (from June to October 2015 and 2016) under natural rainfall conditions. The results showed that the mean SWC in the natural grassland was approximately 30% higher than those in the planted grasslands. The SWC consumption of the planted legume grasslands in the deepest soil layers (below 200 cm) was higher than that of the natural grassland, owing to the deep root system of the legumes. Both natural and planted grasslands had low SWC temporal stability in the top soil layers (0–50 cm), whereas more stable conditions were gradually observed with increasing the soil depth. The mean value of the mean relative differences of SWC in natural grassland (ca. 15%) was lower than that in the planted grasslands (A. cristatum grasslands) and much lower than that in the scrubland, highlighting the stronger temporal stability of SWC in the natural grassland. In conclusion, natural grassland could maintain higher and stable SWC and is recommended to be used for achieving sustainable vegetation restoration in arid and semiarid regions.

How Game Addiction Rates and Related Psychosocial Risk Factors Change Within 2-Years: A Follow-Up Study.

ObjectiveProspective data of risky online gamers in Turkey is missing. Therefore, we aimed to investigate the change in gaming behaviors and addiction rates of Travian players within two years to search diagnostic stability of internet gaming disorder and some psychosocial risk factors. Methods110 responders completed the whole questionnaire package including 21-item Game Addiction Scale (GAS), Satisfaction with Life Scale (SLS), Rosenberg Self-Esteem Scale (RSES), and Multi-dimensional Scale of Perceived Social Support (MSPSS). A hierarchical linear modeling approach was followed to test the linear change in game addiction scores of the participants from 2013 to 2015. ResultsGAS scores of gamers significantly decreased within two years (p=0.026). MSPSS scores significantly and negatively associated with GAS scores (p<0.001) and the negative association of time remained significant (p=0.035). Decrement in the MSPSS scores in two years was associated with increment in GAS scores. 9 (90%) of 10 participants with internet gaming disorder according to monothetic format and 26 (52%) of 50 participants with internet gaming disorder according to polythetic format were found to not to meet the diagnosis in the follow-up. 33 out of all participants reported that they were not playing any online games for at least last 6 months. ConclusionSocial support seems to be a protective factor for game addiction and diagnosis of internet gaming disorder has low temporal stability among Travian players in Turkey.

Stable Extended Imaging Area Sensing Without Mechanical Movement Based on Spatial Frequency Multiplexing

Testing process in industrial profiling depends on the characterization of three-dimensional (3-D) objects with high sensitivity in spatial and temporal domains. Ordinary 3-D measurement instruments scan the image area in the temporal domain; therefore, these techniques experience low temporal stability especially for industrial and biomedical sensing. We propose a novel scan-free extended image instrument for sensing the area of 3-D microscopic objects using an interferometric technique with fixed optical parameters, such as resolution, and without mechanical movement. The technique could accelerate the control process in industrial fault detection and images of biological samples could be obtained in a shorter time. First, a stable system for doubling the image area is introduced. Second, the principles underlying the two-dimensional sampling scheme are introduced to record the maximum image area using a dual multiplexing technique at subsampling frequency. Moreover, a standard factor is presented as a figure of merit to determine the exact image area enhancement. Finally, the feasibility of this technique was demonstrated by sensing reflective and transparent objects with image area of up to 4.3-times that of a single-hologram recording using the square scheme. Furthermore, scan-free monitoring of the photolithography process was demonstrated in real-time. The standard deviation of thickness is 0.48 nm, which demonstrates the subnanometer temporal sensitivity of this technique.

Quantification of Human Microbiome Stability Over 6 Months: Implications for Epidemiologic Studies.

Temporal variation in microbiome measurements can reduce statistical power in research studies. Quantification of this variation is essential for designing studies of chronic disease. We analyzed 16S ribosomal RNA profiles in paired biological specimens separated by 6 months from 3 studies conducted during 1985-2013 (a National Cancer Institute colorectal cancer study, a Costa Rica study, and the Human Microbiome Project). We evaluated temporal stability by calculating intraclass correlation coefficients (ICCs). Sample sizes needed in order to detect microbiome differences between equal numbers of cases and controls for a nested case-control design were calculated on the basis of estimated ICCs. Across body sites, 12 phylum-level ICCs were greater than 0.5. Similarly, 11 alpha-diversity ICCs were greater than 0.5. Fecal beta-diversity estimates had ICCs over 0.5. For a single collection with most microbiome metrics, detecting an odds ratio of 2.0 would require 300-500 cases when matching 1 case to 1 control at P = 0.05. Use of 2 or 3 sequential specimens reduces the number of required subjects by 40%-50% for low-ICC metrics. Relative abundances of major phyla and alpha-diversity metrics have low temporal stability. Thus, detecting associations of moderate effect size with these metrics will require large sample sizes. Because beta diversity for feces is reasonably stable over time, smaller sample sizes can detect associations with community composition. Sequential prediagnostic specimens from thousands of prospectively ascertained cases are required to detect modest disease associations with particular microbiome metrics.

Low Temporal Stability of Excessive Video Game Use in German Adolescents

Abstract. The popularity of digital games among adolescents has raised public and scientific concern about players drifting into excessive or pathological gaming patterns. Among the neglected issues in this area of research is the question of whether excessive gaming reflects a transient phenomenon during adolescence or a temporally stable pathological behavior that requires external intervention. In a correlational panel study with two points of measurement, we investigated the temporal stability of excessive gaming in German adolescents (N = 488; aged 12–17 years at Time 1) over a time lag of 1 year. Among the video game players in our sample, 2.8% were classified as excessive gamers at both points of measurement. The correlation of excessive gaming between T1 and T2 was found to be relatively moderate (r = .54). Detailed inspection revealed even lower stability scores for each single component of excessive gaming such as tolerance or conflict, with the most problematic elements (stealing, borrowing money because of gaming problems) displaying the lowest stabilities (r &lt; .30). Thus, the results indicate that – at least for the large majority of adolescent players – excessive gaming is a transient and not a stable condition. Theoretical and policy implications are discussed.