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Hippocampal dentation (HD) refers to a series of ridges (dentes) seen on the inferior aspect of the hippocampus. The degree of HD varies dramatically across healthy individuals, and hippocampal pathology may result in loss of HD. Existing studies show associations between HD and memory performance in healthy adults as well as temporal lobe epilepsy (TLE) patients. However, until now studies relied on visual assessment of HD as no objective methods to quantify HD have been described. In this work, we describe a method to objectively quantify HD by transforming the characteristic 3D surface morphology of HD into a simplified 2D plot for which area under the curve (AUC) was calculated. This was applied to T1w scans of 59 TLE subjects, each with one epileptic hippocampus and one normal appearing hippocampus. Results showed that AUC significantly correlated with the number of dentes based on visual inspection (p <.05) and correctly sorted a set of hippocampi from least to most prominently dentated. Intra‐ and inter‐rater reliability was nearly perfect (ICC ≥ 0.99). AUC values were significantly lower in epileptic hippocampi compared to contralateral hippocampi (p =.00019), consistent with previously published findings. In the left TLE group, the AUC values from the contralateral hippocampi showed a positive trend (p =.07) with verbal memory acquisition scores but was not statistically significant. The proposed approach is the first objective, quantitative measurement of dentation described in the literature. The AUC values numerically capture the complex surface contour information of HD and will enable future study of this interesting morphologic feature. [ABSTRACT FROM AUTHOR]

The neurological disorders are developed in adults due to reduced visual perception. Opto Kinetic Nystagmus (OKN) is a clinical method to detect visual perception. For objective measurements, a computational algorithm based OKN detection is preferable rather than clinical practice. In this paper, a memory-efficient Subsampled Lucas-Kanade Optical Flow (SLKOF) is proposed. The proposal employs the Subsampling of images for various levels. The proposal deals with the computation of OKN gain for different image Subsampling factors using the MATLAB platform. The experimental set up to observe OKN is done using computer-based rotation control of the drum through a stepper motor. The results are compared with the well established Lucas-Kanade (LK) method for Optical flow. It is observed that OKN gain corresponds to 1/4th of a subsampled image of the SLKOF method correlates with the LK method for the majority of the cases. This validation evidently elucidates that the proposal is computationally efficient. [ABSTRACT FROM AUTHOR]

Purpose: Assessing binocular accommodative facility (BAF) enables the evaluation of the interaction between the accommodative and vergence systems, which is relevant for the diagnosis of accommodative and binocular disorders. However, the tests used to assess BAF present methodological caveats (e.g., lack of objective control, vergence demands, and image size alterations), limiting its external validity. This study aimed to (i) develop a new objective method to quantitatively and qualitatively evaluate the BAF in free-viewing conditions, and explore its validity by the comparison with the Hart Chart test, and (ii) assess the inter-session reliability of the proposed method. Methods: 33 healthy young adults took part in this study. We used a binocular open-field autorefractor to continuously assess the magnitude of accommodative response during a 60-sec period, while participants repeatedly changed fixation from a far to a near chart when clarity of vision was achieved at each level. Accommodative response data were used to characterize the BAF measurement in quantitative (number of cycles) and qualitative terms (percentage of times that correctly accommodating or dis-accommodating in each level of accommodation as well as the magnitude of the accommodative change). Results: Our data revealed that the new proposed method accurately counted the number of cycles per minute when compared with the Hart Chart test (p =.23, ES = 0.02; mean difference = 0.18 ± 0.85). The inter-session reliability of the proposed method was demonstrated to be excellent (Pearson r and intraclass correlation coefficient: 0.95 to 0.98) for the parameters obtained with the BAF test. Conclusions: The present outcomes evidence that the proposed objective method allows to accurately assess the frequency and precision of BAF by the combination of the classical Hart Chart test and a binocular open-field autorefractometer. Our findings may be of relevance for the diagnosis and treatment of accommodative and binocular disorders. [ABSTRACT FROM AUTHOR]

In this work, the use of an objective method, the formulation of the Rasch measurement model, which synthesizes data from different susceptible elements for maintenance (SEM) and healthcare units (HU) into a uniform analytical framework, is considered to get representative measures of corrective maintenance demand in an hospital. Thus, information about 10 SEM and 33 HU were obtained from two hospital located in Badajoz (Spain) to be treated. A latent variable, denominated corrective maintenance demand, was defined. It is supposed, and later it is verified, that all SEM previously indicated have a marked influence on the latent variable. The adequate assignment of categorical values across SEM measures and the good fit of the data are checked as a previous phase to properly compute the Rasch measures. After applying the Rasch methodology, it was obtained that the mean corrective maintenance demand of HU is lower than expected, but significative differences between units are apparent. Those which care for high risk patients, as liver transplant, intensive care, and internal medicine, are the most influential units on corrective maintenance demand, getting moreover a ranking of all HU according to their corrective maintenance demand. Similarly, another ranking of all SEM is provided, being hospital furniture the item that exerts the highest influence on corrective maintenance demand. Moreover, the unexpected behaviors, called misfits, of some HU and SEM constitute a very useful information to better know the hospital requirements and correctly allocate the work hours in the maintenance management program. Consequently, the Rasch measurement model is a very useful tool for decision making related to corrective maintenance cost management and their correct attribution to each healthcare unit. [ABSTRACT FROM AUTHOR]

A mathematical algorithm for the automatic detection and tracking of Mediterranean cyclones is presented. The objective of this study is identifying those Mediterranean cyclones that are engaged on various trajectories towards the countries bordering the Black Sea. Mediterranean cyclones with trajectories towards Romania have been identified from a six‐hourly reanalysis of mean sea level pressure (MSLP) data set for a period of 37 years (January 1980–December 2016) within the chosen domain 15 ° W–40 ° E/30 ° N–50 ° N. The cyclone identification was performed using a method known as calculus cyclone identification (CCI), which was adapted for the Mediterranean Sea region. The results obtained using the objective method were compared with the Mediterranean cyclone trajectory data obtained about 55 years ago by Romanian researchers who made use of subjective methods. A summary of the climatology of Mediterranean cyclones affecting Romania was also performed. To demonstrate the accuracy of the objective method adapted for the cyclones engaged on trajectories towards Romania, a subjective analysis using the potential vorticity and geopotential height fields was made. The results confirmed that the method can be successfully implemented by the Romanian Meteorological Service for the detection of Mediterranean cyclones. This method will, therefore, be a useful tool for meteorologists in their forecasting activity. [ABSTRACT FROM AUTHOR]

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Consider a simple locally finite hypergraph on a countable vertex set, where each edge represents one unit of load which should be distributed among the vertices defining the edge. An allocation of load is called balanced if load cannot be moved from a vertex to another that is carrying less load. We analyze the properties of balanced allocations of load. We extend the concept of balancedness from finite hypergraphs to their local weak limits in the sense of Benjamini and Schramm (Electron J Probab 6(23):13, 2001) and Aldous and Steele (in: Probability on discrete structures. Springer, Berlin, pp 1-72, 2004). To do this, we define a notion of unimodularity for hypergraphs which could be considered an extension of unimodularity in graphs. We give a variational formula for the balanced load distribution and, in particular, we characterize it in the special case of unimodular hypergraph Galton-Watson processes. Moreover, we prove the convergence of the maximum load under some conditions. Our work is an extension to hypergraphs of Anantharam and Salez (Ann Appl Probab 26(1):305-327, 2016), which considered load balancing in graphs, and is aimed at more comprehensively resolving conjectures of Hajek (IEEE Trans Inf Theory 36(6):1398-1414, 1990). [ABSTRACT FROM AUTHOR]

Simple, rapid staining analytical methods with visual color assessment are the most used in practice, but they involve problems including subjective error, low accuracy, qualitative results, and the necessity of using many kinds of stains and a great deal of morphology information for correct identification. A method of objective fiber identification using color vectors of a microscan from stained fibre digital photography is described in this report. A model set of cellulose fibres was prepared: groundwood; sulphate pulp; Whatman paper; and rag fibres. The objective micro-colorimetric method, using RGB (red, green, blue) vectors with discriminatory analysis, reduced the number of stains to 1; requires no morphological information; and the discriminatory power (dp,) of this approach is up to 95 to 100% of correctly identified unknown samples with one color vector R or B. A dp value of 100% was achieved when using 2-P or 3-P combinations of R, G, and B. [ABSTRACT FROM AUTHOR]

In this study, the Alpha (α) body condition scoring system was proposed as an alternative to the subjective condition scoring and its applicability was tested in Brown Swiss dairy cattle. This system was based on measuring the angles formed by depressed hip occurred in the thurl area, and provides information about cattle body condition. Measurements were done by depth gauge . Fifty Brown Swiss milk cows' values of Alpha angles, which corresponded to the subjective 5 scoring system, were determined for each score that matches its feature. Furthermore, in order to test its reliability and applicability, 5 farmers, with no prior experience in scoring were asked to determine the condition scores of 50 Brown Swiss milk cows both objectively and subjectively and results were compared. The correlation coefficients between the values determined by assessors were examined and it was understood that the Alpha (α) condition score method was more reliable but required more care, time and labor. [ABSTRACT FROM AUTHOR]

Background: Deviated nasal septum (DNS) is one of the major causes of nasal obstruction. Polyvinylidene fluoride (PVDF) nasal sensor is the new technique developed to assess the nasal obstruction caused by DNS. This study evaluates the PVDF nasal sensor measurements in comparison with PEAK nasal inspiratory flow (PNIF) measurements and visual analog scale (VAS) of nasal obstruction. Methods: Because of piezoelectric property, two PVDF nasal sensors provide output voltage signals corresponding to the right and left nostril when they are subjected to nasal airflow. The peak-to-peak amplitude of the voltage signal corresponding to nasal airflow was analyzed to assess the nasal obstruction. PVDF nasal sensor and PNIF were performed on 30 healthy subjects and 30 DNS patients. Receiver operating characteristic was used to analyze the DNS of these two methods. Results: Measurements of PVDF nasal sensor strongly correlated with findings of PNIF (r = 0.67; p < 0.01) in DNS patients. A significant difference (p < 0.001) was observed between PVDF nasal sensor measurements and PNIF measurements of the DNS and the control group. A cutoff between normal and pathological of 0.51 Vp-p for PVDF nasal sensor and 120 L/min for PNIF was calculated. No significant difference in terms of sensitivity of PVDF nasal sensor and PNIF (89.7% versus 82.6%) and specificity (80.5% versus 78.8%) was calculated. Conclusion: The result shows that PVDF measurements closely agree with PNIF findings. Developed PVDF nasal sensor is an objective method that is simple, inexpensive, fast, and portable for determining DNS in clinical practice. [ABSTRACT FROM AUTHOR]

The color of refined palm oil and palm oil products is conventionally measured using the manually operated Lovibond® Tintometer. In the present study, one manual/visual and three automatic colorimeters for the measurement of vegetable oil color were used for color measurements of refined palm oil. All colorimeters used were commercially available instruments except for an automatic palm oil colorimeter developed specifically for the measurement of palm oil color. The color values obtained from all four instruments were compared using the visually obtained readings as reference values. Results showed that all three automatic instruments gave correlation coefficients of greater than 0.9300 for red color measurements. In addition, the Student t-test showed no difference between the analysis of red color using the visual method and the palm oil colorimeter. This investigation concludes that, although it is extremely difficult to reduce the lack of precision in color measurement of palm oil, a properly designed and calibrated automatic instrument may still be the better choice because reproducibility and repeatability are required in all standard test methods. The palm oil colorimeter offers a ready and relatively inexpensive solution to the problem of color matches based on visual observations. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to an article about a method to evaluate the efficacy of vitiligo treatment.