Effects of visual blur and contrast on spatial and temporal precision in manual interception

The visual system is said to be especially sensitive towards spatial but lesser so towards temporal information. To test this, in two experiments, we systematically reduced the acuity and contrast of a visual stimulus and examined the impact on spatial and temporal precision (and accuracy) in a manual interception task. In Experiment 1, we blurred a virtual, to-be-intercepted moving circle (ball). Participants were asked to indicate (i.e., finger tap) on a touchscreen where and when the virtual ball crossed a ground line. As a measure of spatial and temporal accuracy and precision, we analyzed the constant and variable errors, respectively. With increasing blur, the spatial and temporal variable error, as well as the spatial constant error increased, while the temporal constant error decreased. Because in the first experiment, blur was potentially confounded with contrast, in Experiment 2, we re-ran the experiment with one difference: instead of blur, we included five levels of contrast matched to the blur levels. We found no systematic effects of contrast. Our findings confirm that blurring vision decreases spatial precision and accuracy and that the effects were not mediated by concomitant changes in contrast. However, blurring vision also affected temporal precision and accuracy, thereby questioning the generalizability of the theoretical predictions to the applied interception task.

ASTRO

We present the design, implementation, and experimental evaluation of ASTRO, a modular end-to-end system for distributed sensing missions with autonomous networked drones. We introduce the fundamental system architecture features that enable agnostic sensing missions on top of the ASTRO drones. We demonstrate the key principles of ASTRO by using on-board software-defined radios to find and track a mobile radio target. We show how simple distributed on-board machine learning methods can be used to find and track a mobile target, even if all drones lose contact with a ground control. Also, we show that ASTRO is able to find the target even if it is hiding under a three-ton concrete slab, representing a highly irregular propagation environment. Our findings reveal that, despite no prior training and noisy sensory measurements, ASTRO drones are able to learn the propagation environment in the scale of seconds and localize a target with a mean accuracy of 8 m. Moreover, ASTRO drones are able to track the target with relatively constant error over time, even as it moves at a speed close to the maximum drone speed.

Lumbo-pelvic proprioception in sitting is impaired in subgroups of low back pain–But the clinical utility of the differences is unclear. A systematic review and meta-analysis

Background Altered spinal postures and altered motor control observed among people with non-specific low back pain have been associated with abnormal processing of sensory inputs. Evidence indicates that patients with non-specific low back pain have impaired lumbo-pelvic proprioceptive acuity compared to asymptomatic individuals. Objective To systematically review seated lumbo-pelvic proprioception among people with non-specific low back pain. Methods Five electronic databases were searched to identify studies comparing lumbo-pelvic proprioception using active repositioning accuracy in sitting posture in individuals with and without non-specific low back pain. Study quality was assessed by using a modified Downs and Black’s checklist. Risk of bias was assessed using an adapted tool for cross-sectional design and case–control studies. We performed meta-analysis using a random effects model. Meta-analyses included subgroup analyses according to disability level, directional subgrouping pattern, and availability of vision during testing. We rated the quality of evidence using the GRADE approach. Results 16 studies met the eligibility criteria. Pooled meta-analyses were possible for absolute error, variable error, and constant error, measured in sagittal and transverse planes. There is very low and low certainty evidence of greater absolute and variable repositioning error in seated tasks among non-specific low back pain patients overall compared to asymptomatic individuals (sagittal plane). Subgroup analyses indicate moderate certainty evidence of greater absolute and variable error in seated tasks among directional subgroups of adults with non-specific low back pain, along with weaker evidence (low-very low certainty) of greater constant error. Discussion Lumbo-pelvic proprioception is impaired among people with non-specific low back pain. However, the low certainty of evidence, the small magnitude of error observed and the calculated “noise” of proprioception measures, suggest that any observed differences in lumbo-pelvic proprioception may be of limited clinical utility. PROSPERO-ID CRD42018107671

Lightweight Detection of a Small Number of Large Errors in a Quantum Circuit

Suppose we want to implement a unitary U, for instance a circuit for some quantum algorithm. Suppose our actual implementation is a unitary U~, which we can only apply as a black-box. In general it is an exponentially-hard task to decide whether U~ equals the intended U, or is significantly different in a worst-case norm. In this paper we consider two special cases where relatively efficient and lightweight procedures exist for this task.First, we give an efficient procedure under the assumption that U and U~ (both of which we can now apply as a black-box) are either equal, or differ significantly in only one k-qubit gate, where k=O(1) (the k qubits need not be contiguous). Second, we give an even more lightweight procedure under the assumption that U and U~ are Clifford circuits which are either equal, or different in arbitrary ways (the specification of U is now classically given while U~ can still only be applied as a black-box). Both procedures only need to run U~ a constant number of times to detect a constant error in a worst-case norm. We note that the Clifford result also follows from earlier work of Flammia and Liu, and da Silva, Landon-Cardinal, and Poulin.In the Clifford case, our error-detection procedure also allows us efficiently to learn (and hence correct) U~ if we have a small list of possible errors that could have happened to U; for example if we know that only O(1) of the gates of U~ are wrong, this list will be polynomially small and we can test each possible erroneous version of U for equality with U~.

A Neural Network in Convolution with Constant Error Carousel Based Long Short Term Memory for Better Face Recognition

Unconstrained face identification, facial periocular recognition, facial land marking and pose prediction, facial expression recognition, 3D facial model design, and other facial-related problems require robust face detection in the wild. Despite the fact that the face recognition issue has been researched intensively for decades with different commercial implementations, it nevertheless faces problems in certain real-world scenarios due to multiple obstacles, such as severe facial occlusions, incredibly low resolutions, intense lighting, exceptionally pose inconsistencies, picture or video compression artefacts, and so on. To solve the problems described above, a face detection technique called Convolution Neural Network with Constant Error Carousel dependent Long Short Term Memory (CNN-CEC-LSTM) is proposed in this paper. This research implemented a novel network structure and designed a special feature extraction that employs a self-channel attention (SCA) block and a self-spatial attention (SSA) block that adaptively aggregates the feature maps in both channel and spatial domains to learn the inter-channel and inter-spatial connection matrices; additionally, matrix multiplications are conducted for a This approach first smoothed the initial image with a Gaussian filter before measuring the gradient image. The Canny-Kirsch Method edge detection algorithm was then used to identify human face edges. The proposed method is evaluated against two recent difficult face detection databases, including the IIT Kanpur Dataset. The experimental findings indicate that the proposed approach outperforms the most current cutting-edge face recognition approaches.

Differential white blood cell counts in rabbits: a comparison of the Advia 2120 and a manual method

We evaluated the performance of the Advia 2120 (Siemens) differential leukocyte count (A-Diff) compared to the manual method (M-Diff) in rabbits. EDTA-anticoagulated blood samples collected for diagnostic purposes were analyzed within 6 h of collection. The M-Diff was performed blindly by 2 observers on blood smears by counting 200 cells. We initially included 117 samples; 25 samples were excluded because of suboptimal gating of leukocytes in the Advia peroxidase cytogram or poor blood smear quality. The correlation between the A-Diff and M-Diff was very high for heterophils (r = 0.924, p < 0.001) and lymphocytes (r = 0.903, p < 0.001), high for basophils (r = 0.823, p < 0.001), moderate for monocytes (r = 0.645, p < 0.001), and low for eosinophils (r = 0.336, p = 0.001). The Passing–Bablok regression analyses revealed a small-to-moderate constant error for lymphocytes and a slight constant error for basophils. Small proportional errors were detected for heterophils, lymphocytes, and eosinophils. The Bland–Altman analyses revealed that the Advia significantly underestimates heterophils and overestimates lymphocytes compared to M-Diff. The biases for the other leukocytes were minimal and likely clinical insignificant; however, our results, particularly for eosinophils, should be interpreted cautiously given the observed low percentages in our samples. Given the observed biases in heterophil and lymphocyte percentages in the Advia 2120 CBC results in rabbits, method-specific reference intervals should be used. The Advia can recognize leporine basophils. Evaluation of blood smears is still recommended to investigate abnormal results and erroneous cytograms reported by the Advia.

Resolvable mating-environmental designs for partial triallel cross experiments

Triallel crosses can be readily exploited as breeding tool for developing commercial hybrids with traits of genetical and commercial importance by acquiring information on specific combining ability effects along with general combining ability effects if the experimentation size is reduced to an economical extent. In this paper, methods of constructing designs involving partial triallel crosses in smaller blocks using different types of lattice designs have been introduced. The designs have low degree of fractionation, which suggests their utility when there is a resource crunch. Canonical efficiency factor of these designs relative to an orthogonal design with same number of lines, assuming constant error variance for both situations, is high indicating that adoption of these designs for the trials could bring about improvement as the recommendations from the experiment will be associated with a high precision.

Comparison of three methods for determining anti-thyrotropin receptor antibodies (TRAb) for diagnosis of Graves’ disease: a clinical validation

Objectives Graves’ disease is secondary to the presence of anti-thyrotropin receptor antibodies (TRAb), which stimulate thyroid hormones. TRab determination is crucial for etiological diagnosis. The objectives of this study were (i) to compare two methods for determining TRab by chemoluminiscence vs. standard TRACE-immunofluorescence; (ii) to determine the diagnostic validity of the three methods. Methods A retrospective study in 194 patients with a TRAb determination request. TRAb were determined by immunofluorescence (Kryptor, ThermoFisher) and chemiluminescence (Immulite, Siemens and Maglumi, Snibe). Clinical validation: medical records were reviewed and categorized according to thyroid function. Statistical analysis: Differences in quantitative variables were assessed by intraclass correlation coefficient, Bland–Altman plot, and mean differences (mD). Qualitative variables were dichotomized by cut-off points; Kappa coefficient was calculated. Correlations were evaluated by Pearson’s coefficient and Passing-Bablok regression analysis. The diagnostic validity of the three methods was investigated. Results Kryptor-Immulite: mD: 1.2 (95%CI: −16 to >18). Passing-Bablok: Constant error (95%CI: −0.8349 to −0.5987). Proportional error (95%CI: 0.7862–1.0387). ICC: 0.86 (95%CI: 0.82–0.89). Kappa coefficient: 0.68 (95%CI 0.59–0.78). Kryptor-Maglumi: mD: −0.3 (95%CI: −12 to >12). Passing-Bablok: Constant error (95%CI: −0.7701 to >0.1621. Proportional error (95%CI: 0.8571 to 1.3179. ICC: 0.93 (95%CI: 0.89–0.97). Kappa coefficient: 0.53 (95%CI: 0.32–0.74). Diagnosis of Graves’ disease was confirmed in 113 patients (Kryptorf showed better specificity and positive predictive value, whereas Immulite demonstrated better sensitivity and negative predictive value). Conclusions The three methods have a good diagnostic performance for Graves’ disease, with superimposable results on Bland–Altman plot. Interchangeability was not confirmed on the regression and agreement analysis, with the presence of biases.

Shoulder Joint Position Sense Can Be Reduced by Sensory Reference Frame Transformations

Joint position sense (JPS) is commonly evaluated using an angle replication protocol with vision occluded. However, multiple sources of sensory information are integrated when moving limbs accurately, not just proprioception. The purpose of this study was to examine different availability of vision during an active JPS protocol at the shoulder. Specifically, the effects of four conditions of vision availability were examined for three target shoulder elevation angles (50°, 70° & 90°): vision occluded continuously (P-P); vision available continuously (VP-VP); vision occluded only during target memorization (P-VP); and vision occluded only during target position replication (VP-P). There were 18 participants ( M age = 21, SD = 1 years). We used separate repeated ANOVAs to examine the effect of condition and target angle on participants’ absolute error (AE, a measure of accuracy) and constant error (CE, a measure of directional bias). We found a significant main effect for condition and angle for both dependent variables ( p < 0.01), and follow-up analysis indicated that participants were most accurate in the VP-VP condition and least accurate in the P-VP condition. Further follow-up analysis showed that accuracy improved with higher target elevation angles, consistent with previous research findings. Constant error results were similar, as there was a prominent tendency to overshoot the target. Unsurprisingly, participants performed best at the angle replication protocol with their eyes open. However, while accuracy was reduced when vision was occluded during target memorization, it was restored during target replication. This finding may have indicated an accuracy cost due to introduced noise when transforming sensory information from a proprioceptive reference frame into a visual reference frame.

Validation of anthropometric equations for predicting body mass and height in older women

To investigate the cross-validity of two equations widely used in national research to predict body mass and height in older Brazilians. Additionally, the importance of possible differences between observed and predicted BMI will be investigated with the help of equations. BM and HEI were measured using mechanical scales and portable stadiometers in a sample of 200 older women (66.6 ± 5.43 years) living in Maceió / AL - Brazil. To verify the validity of equations, the following variables were used: Student's t-test, constant error (CE), total error (TE) and standard error of estimation (SEE). To verify agreement between actual and predicted values, the Bland-Altman test was used. The comparison between BM and HEI values obtained through equations and those verified in measurements showed statistically significant differences (p <0.05). CE between predicted and measured values, TE of tested equations, as well as SEE for the prediction of variables: BM (1.66; 0.11 and 6.33), HEI (-0.02; 0.02 and 0.10) and BMI (1.47; 0.10 and 3.24) allowed determining relative values very close to actual ones (2.6%, 1.31% and 5.3% for BM, HEI and BMI respectively); however, values were not statistically significant. The equations analyzed should not be used in a general way for the population of older Brazilian women with characteristics similar to those analyzed in this study. Therefore, further studies should be carried out with the objective of constructing specific equations for the population of older women and hospitalized patients, especially the most fragile ones.