Equidistant Points Research Articles

Fisher Information-Based Optimization of Mapped Fourier Grid Methods

The mapped Fourier grid method (mapped-FGM) is a simple and efficient discrete variable representation (DVR) numerical technique for solving atomic radial Schrödinger differential equations. It is set up on equidistant grid points, and the mapping, a suitable coordinate transformation to the radial variable, deals with the potential energy peculiarities that are incompatible with constant step grids. For a given constrained number of grid points, classical phase space and semiclassical arguments help in selecting the mapping function and the maximum radial extension, while the energy does not generally exhibit a variational extremization trend. In this work, optimal computational parameters and mapping quality are alternatively assessed using the extremization of (coordinate and momentum) Fisher information. A benchmark system (hydrogen atom) is employed, where energy eigenvalues and Fisher information are traced in a standard convergence procedure. High-precision energy eigenvalues exhibit a correlation with the extrema of Fisher information measures. Highly efficient mapping schemes (sometimes classically counterintuitive) also stand out with these measures. Same trends are evidenced in the solution of Dalgarno–Lewis equations, i.e., inhomogeneous counterparts of the radial Schrödinger equation occurring in perturbation theory. A detailed analysis of the results, implications on more complex single valence electron Hamiltonians, and future extensions are also included.

Comparative Evaluation of the Marginal Fit and Internal Adaptation of Polymethyl Methacrylate Interim Crowns Fabricated using two different techniques- “Conventional” and “CAD-CAM Milling”: An In Vitro Study

Introduction Interim crowns provide valuable functional and esthetic information of the final outcome during the evaluation period and act as the blueprint for the design of definitive prostheses. The fabrication technique and material used are the key factors involved in the success of the prosthesis. However, marginal fit and internal adaptation of Polymethyl Methacrylate (PMMA) interim crowns fabricated using conventional and computer aided designing-computer aided machining (CAD-CAM) PMMA milling have not been well investigated. The inter-group statistical comparison of means of normally distributed continuous variables is done using independent sample t test. Material and Methods Typodont (Nissin, Japan) of the maxillary central incisor was scanned (Ceramill Map 600+, Amann Girrbach AG) and 3D printed (Form 4, Formlabs) to create the master die used in the study, while a Typodont of a prepared maxillary central incisor was scanned using a digital scanner (Ceramill Map 600+, Amann Girrbach AG) and a .STL file obtained was modified using Exocad software for designing the study models. Three equidistant points A, B and C passing from the center of the incisal edge to the root of the typodont were indented labially and A` B` and C` were indented palatally in the same plane using Exocad software for symmetrical sectioning while checking for marginal fit and internal adaptation. 50 3D printed (Form 4, Formlabs India) models of the prepared tooth were printed and 25 interim crowns were fabricated using Polymethyl Methacrylate (DPI Tooth moulding material, DPI India) by conventional and 25 interim crowns were fabricated using CAD-CAM PMMA (Ceramill a-temp, Amann Girrbach AG). They were then luted (Han Temp Cement eugenol free, NE Korea) to respective models and viewed under a stereomicroscope (Ziess) for marginal fit at 2 specific points and internal adaptation at 4 specific points. Results The mean SD of marginal fit measurements at buccal and site in Group A (conventional technique) and Group B (CAD-CAM milling) was 95.32 ± 7.78 µm and 66.92 ± 14.59 µm respectively. At lingual site in Group A and Group B was 94.84 ± 7.97 µm and 66.80 ± 10.93 µm respectively. The mean marginal fit measurement at lingual site is significantly higher in Group A compared to Group B (P-value%3C0.05). The mean SD of internal fit measurements at upper 1 site in Group A and Group B was 335.19 ± 94.70 µm and 226.76 ± 89.68 µm respectively. At upper 2 site in Group A and Group B was 368.88 ± 120.25 µm and 240.85 ± 93.72 µm respectively. At lower 1 site in Group A and Group B was 313.52 ± 99.92 µm and 262.49 ± 94.33 µm respectively. At lower 2 site in Group A and Group B was 367.93 ± 107.36 µm and 264.52 ± 86.97 µm respectively. The mean internal fit measurement is significantly higher in Group A compared to Group B (P-value%3C0.05). Conclusion The interim crowns fabricated using the conventional technique displayed a less favourable marginal fit and internal adaptation when compared to CAD-CAM fabricated interim crowns. Key Words CAD-CAM, Interim crowns, Marginal fit and internal adaptation

Conversion Factor Estimation of Stacked Eucalypt Timber Using Supervised Image Classification with Artificial Neural Networks

Stacked timber is quantified in-store units and then adjusted with a conversion factor for volume estimation in cubic meters, which is important for the wood trade in South America. However, measuring large quantities accurately can be challenging. Digital image processing and artificial intelligence advancements offer promising solutions, making research in this area increasingly attractive. This study aims to estimate conversion factors of stacked Eucalyptus grandis timber using supervised image classification with Artificial Neuronal Network (ANN). Measured data and photographs from an experiment involving thirty stacks of timber were used to achieve this. The conversion factor was determined using photographic methods that involved the applications of equidistant points and ANN and subsequently validated with values observed through the manual method. The ANN method produced more accurate conversion factor estimates than the equidistant points method. Approximately 97% of the ANN estimates were within the ±1% error class, even when using low-resolution digital photographs.

Optimized Walking Route Method for Precision Coffee Farming

Coffee production has become increasingly technified in order to optimize the use of inputs and the sustainable use of natural resources. In this context, one way that farmers are investing in their coffee plantations is in the use of precision agriculture techniques, termed precision coffee farming. Over the last few years, research has been conducted to facilitate the application of this technology, and sampling grids with two points per hectare have been recommended by several studies. These georeferenced demarcations in a plot are generally shaped as equidistant squares or rectangles, and the sampling points are located at the centers of these areas. Coffee farmers typically plant their crops following the level line, which greatly hinders the navigation of equidistant points within the field. Thus, the objective of this study was to develop an optimized walking route method to reduce the distance for sampling soil, leaf, and yield attributes. The experimental plots were established in 2000 at Samambaia Farm, located in Santo Antônio do Amparo, Minas Gerais, Brazil, with coffee the cultivar Acaia IAC 479-19, totaling 56.65 ha. The 111 sampling points were distributed in the land following the new method proposed in this study, and, after walking simulations using Farm Works Mapping Software, the new method was compared with the conventional method using the mean displacement between points. The new optimized walking routes method reduced the mean distance traveled to sample the points by 50.1%.

Thrivers and Survivors during Study Abroad: The Individual Cases of Japanese Learners of English

Whilst study abroad (SA) periods hold much promise for foreign language development, increasing research suggests sojourners’ experiences are unique, and language development does not always follow a linear trajectory. For some learners, SA has little impact on their language performance despite the affordances of L2 immersion (the Survivors). Other learners maximise the potential of SA, and this has a positive impact on their language development (the Thrivers). This paper examines the selected cases of four Japanese learners of English and their request language performance during a 10-month SA in the UK. Changes in pragmatic knowledge (based on appropriateness ratings) were documented at three equidistant time points. Language contact profile data also provided quantitative insights into the learners’ extracurricular language use and qualitative personal reflections. The selected cases illustrate two learners surviving the SA experience, showing minimal change in their request performance. The other two learners thrived during SA, showing accelerated performance in terms of lexical variation at the production level. This paper reports on the case histories of these learners to better understand these unique experiences and pragmatic discrepancies. Suggestions for how learners might be more pragmatically successful during SA are also offered.

An extension of a mixed interpolation–regression method using zeros of orthogonal polynomials

The constrained mock-Chebyshev least squares approximation (CMCLS-approximation) is a method that has been recently introduced. It operates on a grid of equidistant points, aiming to eliminate the Runge phenomenon. The implementation of the idea behind this approximation method involves interpolating the function exclusively on the subset of nodes closer to the set of Chebyshev–Lobatto nodes of a suitable order and using the remaining nodes to enhance the accuracy of the approximation through a simultaneous regression. The main goal of this article is to extend the CMCLS-approximation through the interpolation on zeros of orthogonal polynomials, leveraging their inherent favorable properties.

Radiographic Evidence of Bone Changes Around Intraosseous Transcutaneous Amputation Prosthesis: An 11-Year Retrospective Cohort Study

ABSTRACT Introduction Percutaneous Osseointegrated Implants (POIs) influence the load transfer path to the host bone. In turn, mechano-regulatory processes (strain adaptive bone remodeling) drive periprosthetic bone changes that influence implant stability and fixation outcome. These bone changes have not yet been reported for the Intraosseous Transcutaneous Amputation Prosthesis (ITAP) clinical trial. Objectives This study will first standardize the zoning and reporting of periprosthetic bone change in POI radiographs. Second, it will retrospectively measure periprosthetic bone change from radiographs of 12 participants with an ITAP up to 11 years. Finally, the results will be qualitatively compared with those from participants with different POI designs. Materials and Methods Twenty participants with unilateral transfemoral amputations received an ITAP in a 2-center UK clinical trial in either 2008/09 or 2013/14. Participant radiographs from one center were available (n = 12) over 11 years and have been collated and processed in a repeatable way. Transverse plane periprosthetic bone change measurements at 3 equidistant points along the implant stem were measured in AP and ML. Results Total median bone growth in AP was double that in ML (57.6 mm and 31.12 mm, respectively). Median lateral and posterior bone change (1.44 mm and 1.09 mm) was greater than median medial and anterior (0.83 mm and −0.005 mm) bone changes, respectively. The greatest change in radial bone growth was observed distally and the least proximally. Conclusions Bone changes were similar to other collared pressfit POIs in the literature. We demonstrate the influence of stem design and mechano-regulatory remodeling in stable fixation; however, additional influences on periprosthetic bone change were inferred from the results and further investigations are necessary. Clinical Relevance To identify ITAP design features and fixations that minimize endosteal resorption, thus promoting implant stability and contributing to clinical guidelines for rehabilitation and future design and fixation choices.

Anatomical Landmarks for Transverse-Sigmoid Sinus Junction: A Cadaveric Study.

Accurately identifying and avoiding crucial anatomical structures within the posterior cranial fossa using superficial landmarks is essential for reducing surgical complications. Our study focuses on the top of the mastoid notch (TMN) as an external landmark of the cranium, aiming to assist in the strategic placement of the initial burr hole. In this study, we present a method for predicting the path of the transverse sinus (TS) and explore the relationship between the junction of the transverse-sigmoid sinus and the TMN. Following anatomical dissections of the brain in cadaveric specimens, we conducted intracranial drilling from the inside surface of the cranium on 10 adult skulls (20 sides). A coordinate system was established on the posterolateral surface of the skull to assist the analysis. Using a self-leveling laser level, we set up a horizontal Frankfurt line (X-axis) and identified a vertical perpendicular line passing through the TMN to serve as the Y-axis. To identify the course of the TS, we divided the segment between the two inferomedial points into six equidistant points along the Frankfurt line. No significant difference was observed between the inferomedial points of the transverse-sigmoid sinus junction (TSSJ) on the left and right sides. The inferomedial point was positioned at a median of 6.6 mm (Q1: 3.7 mm, Q3: 9.4 mm) dorsally and at a median of 19.2 mm (Q1: 16.1 mm, Q3: 23.2 mm) cranially from the TMN. The upper edge of the TS was located at distances of 6.4 mm (5.7; 12.7), 10.3 mm (8.8; 12.3), and 13.8 mm (11.9; 16.3) on the right, and 4.9 mm (4.1; 7.9), 8.6 mm (7.6; 13.0), and 12.8 mm (11.7; 17.5) on the left side from the Frankfurt horizontal plane at the ¼, ½, and ¾ line points, respectively. The bottom edge was positioned at distances of 0.6 mm (-2.7; 2.0), 2.1 mm (-0.8; 3.8), and 4.8 mm (2.4; 6.7) on the right, and 1.1 mm (-3.4; 2.4), 2.0 mm (0.2; 4.8), and 3.9 mm (3.7; 5.3) on the left from these respective points. The upper edge of the right TS was found to be statistically more distant from the Frankfurt horizontal plane at the ¼ line point (p-value = 0.027) compared to that on the left side. The confluence of the sinus center was identified as having a median distance of 7.8 mm (4.5; 8.3) and an inferior point of 1.5 mm (0.1; 3.0) cranially to the inion. In all examined bodies (n = 10), the confluens sinuum was consistently 4.7 mm (3.3; 5.6) to the right in relation to the inion. Notably, the median of the right transverse sinus diameter (median = 9.3 mm) was found to be significantly larger than that of the left transverse sinus (median = 7.0), with a statistically significant p-value of 0.048. The literature regarding the external identification of the TSSJ and the course of the TS varies. In our efforts to provide a description, we have utilized the TMN as a reliable landmark for locating the TSSJ. To delineate the trajectory of the TS after its exit from the confluence of sinuses, we employed a Frankfurt horizontal plane to the inion. These findings may assist surgeons by using external skull landmarks to identify intracranial structures within the posterior fossa, particularly when image guidance devices are not available or to complement a neuronavigational system.

Biomonitoring of the confluence of the Maguaca and Yuna rivers, Cotui, Dominican Republic

The degradative processes such as mining cause loss of species, forest cover, ecosystem services and contaminate bodies of water. Under this problem, the behavior of the water quality of the confluence of the Maguaca and Yuna rivers, in the municipality ofCotuí, Dominican Republic, associated with mining activities, was determined. The research was carried out during two moments: December 2020 (t1) and February 2021 (t2). For this, a deterministic sampling of seven equidistant points in the Maguaca River, and two in the Yuna River, was carried out at t1 in rainy season and t2 in dry season. In addition, the presence of benthic macroinvertebrate species was analyzed as indicators of water quality according to the BMWP-Cub method, and the composition and structure of the riparian vegetation was determined. Likewise, the spatial behavior of the physicochemical variables of water such as potential hydrogen (pH), salinity, electrical conductivity (EC), turbidity, biological oxygen demand (BOD), nitrates (NO3-), chemical oxygen demand (COD), phosphates (PO43-), temperature, dissolved oxygen (O2D), total organic carbon (TOC), and iron concentration (Fe). Water of critical quality (very contaminated) was obtained in the upper part and very critical quality (heavily contaminated) in the lower part, at both times. It is recommended to strengthen monitoring policies for environmental, socioeconomic and health effects.

Pentavalent Antimony Associated with G-CSF in the Treatment of Cutaneous Leishmaniasis Caused by Leishmania (Viannia) braziliensis.

This study compares the effectiveness of G-CSF associated with MA in the treatment of CL. A total of 32 patients aged between 18 and 50 years with CL confirmed for L. braziliensis were included in this study. G-CSF or placebo (0.9% saline) was applied by intralesional infiltration at four equidistant points on the edges of the largest ulcer on days 0 and 15 of treatment associated with intravenous MA. Males predominated in the G-CSF group (59%), while females predominated in the control group (53%). Injuries to the lower limbs predominated in both study groups. The cure rate in the G-CSF group was 65% and in the control group it was 47%, 90 days after initiation of therapy. Our data indicate that the association of G-CSF with MA is not superior to MA monotherapy. Although not significant, the potential benefit of this combination deserves further investigation. The use of higher doses or other routes of application of G-CSF in a greater number of patients should contribute to a definitive response.

Preserving multi-dimensional information: A hypersphere method for parameter space analysis

BackgroundPhysiological modelling often involves models described by large numbers of variables and significant volumes of clinical data. Mathematical interpretation of such models frequently necessitates analysing data points in high-dimensional spaces. Existing algorithms for analysing high-dimensional points either lose important dimensionality or do not describe the full position of points. Hence, there is a need for an algorithm which preserves this information. MethodsThe most-distant uncovered point (MDUP) hypersphere method is a binary classification approach which defines a collection of equidistant N-dimensional points as the union of hyperspheres. The method iteratively generates hyperspheres at the most distant point in the interest region not yet contained within any hypersphere, until the entire region of interest is defined by the union of all generated hyperspheres. This method is tested on a 7-dimensional space with up to 35.8 million points representing feasible and infeasible spaces of model parameters for a clinically validated cardiovascular system model. ResultsFor different numbers of input points, the MDUP hypersphere method tends to generate large spheres away from the boundary of feasible and infeasible points, but generates the greatest number of relatively much smaller spheres around the boundary of the region of interest to fill this space. Runtime scales quadratically, in part because the current MDUP implementation is not parallelised. ConclusionsThe MDUP hypersphere method can define points in a space of any dimension using only a collection of centre points and associated radii, making the results easily interpretable. It can identify large continuous regions, and in many cases capture the general structure of a region in only a relative few hyperspheres. The MDUP method also shows promise for initialising optimisation algorithm starting conditions within pre-defined feasible regions of model parameter spaces, which could improve model identifiability and the quality of optimisation results.

Dynamic auditory-acoustic properties differentiate word-final fricatives in Gitksan

Gitksan is an endangered, understudied Tsimshian language spoken in northwestern British Columbia. This study aims to provide an acoustic-phonetic description of Gitksan fricatives. Isolated words containing word-final fricatives were recorded with three Gitksan first-language speakers (2 male, 1 female; age 65 + ). Postvocalic fricative tokens ([s] = 159, [ɬ] = 123, [ç] = 180, [Xw] = 150, [χ] = 267) were analyzed. Dynamic, spectral measurements of peak frequency in equivalent rectangular bandwidths (peakERB; Reidy, 2016) were estimated from 17 20-ms windows centered at equidistant points between the onset and offset of the fricative. The resulting trajectories (windows 3–15) show that the peakERB decreases as the place of articulation shifts further back in the vocal tract (alveolar [s]∼25–31, palatal [ç]∼20–23, uvular [χ]∼17–19; exception: labiovelar [Xw]∼15–16, likely lowered by labialization). Also, the lateral alveolar [ɬ] shows a lower peakERB (∼22–24) than the central alveolar [s]. A random forest model (Breiman, 2001) was trained on 586 tokens in predicting the fricatives with peakERB measures of the 17 windows. The trained model was tested on 293 tokens; it identified [s] most accurately and [ɬ] least accurately. Additionally, the model's relative-importance ranking of the 17 peakERB predictors suggests that the middle third of the peakERB trajectory is robust in differentiating word-final fricatives in Gitksan.

Spectral properties of Quebec French sibilants

Most acoustic work on sibilants has focused on English /s/ and /ʃ/, examining spectra of the middle portion of these consonants. Voiced sibilants, which are rarer cross-linguistically (Ohala, 1983), as well as sibilants in other languages, have received less attention; in particular, there has been no previous work on Quebec French. Previous cross-linguistic studies have suggested important differences in sibilant acoustics exist between languages (Gordon et al., 2002), including in the dynamics of spectral properties over the course of the segment (Reidy, 2016). This study adds to the literature on the typology of sibilant acoustics by examining the spectral dynamics of sibilants in Quebec French (/s, ʃ, z, ʒ/). ∼28 k word-initial, pre-vocalic tokens from more than 100 speakers are extracted from a large corpus of parliamentary speech (Milne, 2014). For each token, multitaper spectra (Reidy, 2013) over a 20 ms window are calculated at 17 equidistant points. A variety of acoustic measures, including segment duration and spectral moments, are reported. Preliminary results examining static measures reveal that the anterior sibilants have higher spectral speak (∼5700 Hz vs ∼4600 Hz for posterior ones), as expected; unlike in English, however, / s/ and /ʃ/ have similar average duration.

Antibacterial Efficacy of Mineral Trioxide Aggregate, Bioactive Glass and Epoxy-Resin Based Sealer: An In-Vitro Interventional Study.

The aim and objective of this in vitro study was to evaluate the antibacterial efficacy of mineral trioxide aggregate, bioactive glass sealer, and epoxy-resin-based sealer. In the present study, 22 Mueller Hinton agar (MH agar) plates were employed and equally divided into two groups. Three holes were made by removal of agar at equidistant points and filled with root canal sealers. The strains of the bacteria used in this study were S. aureus (ATCC 6538) and C. albicans (ATCC 10231) and were divided into two groups and root canal sealers were divided into three subgroups: mineral trioxide aggregate (MTA) fillapex Sealer, Nishika Bioactive Glass sealer, and Syntex Epoxy Resin base sealer. For Staphylococcus aureus, peptone water was placed in a 2 mL test tube and bacteria were extracted from blood agar plates using a nichrome wire loop and poured into the peptone water-containing test tube and incubated for 2 hours and for C. albicans, fungi were grown at 37°C for 24 hours in MH Broth and seeded into MH agar to produce turbidity of 0.5 on the McFarland scale, which corresponds to a concentration of 108 CFU/mL. This MH broth was used as a second layer. The seeded agar was then added over the plates immediately after the insertion of sealer cement. After incubation, the diameters of zones of inhibition around the plates were measured. The results of this study showed that the highest inhibition was recorded in Syntex sealer against Staphylococcus aureus followed by MTA fillapex sealer and Nishika sealer, whereas MTA fillapex showed the highest inhibition against C. albicans followed by Syntex sealer and Nishika sealer. Syntex sealer exhibits better antibacterial efficacy against Staphylococcus aureus and MTA fillapex exhibit better antibacterial efficacy against C. albicans.

What are optimum cycles for immediate primary closure of large cutaneous defects?

In the reconstruction of large complex cutaneous wounds, a myriad of mechanical devices has been designed to facilitate primary wound closure. However, there is a dearth of studies elucidating how best to achieve optimum use and efficiency of skin stretching (SS) when using the device for immediate primary closure of defects. Skin defect wounds (7 × 7 cm) were prepared on the back of three Bama miniature pigs. A total of 15 cycles of SS (cycle loading) were subsequently performed on the skin edges of the wound by EASApprox® SS system. Then, the changes in equidistant points were recorded after each cycle. After the SS test, all wounds were sutured under low tension. Skin elongation was observed at all equidistant points on the back wounds of three Bama miniature pigs. Up to an additional 1.10 to 3.75 cm of tissue was garnered. The maximum skin elongation was typically achieved within eight cycles of stretching and relaxation. Beyond this range, additional stretching cycles did not result in further skin extension. There may be a close link between mobilization range and the times of acute cyclic stretching (cycle loading) during the process of primary wound closure. However, larger studies are required to further evaluate the accuracy and effectiveness.

D-optimal designs for a two-dimensional polynomial model

The influence of an affine transformation of the design space on the number of support points in the D-optimal design has been studied for a two-dimensional polynomial regression model. For a full rank model of degree n, a result was obtained that determines the structure of the D-optimal plan. It is proven that for a region of design space that is symmetric about zero, the optimal plan is symmetric as well. This result allows for a significant reduction in the dimensionality of the optimization problem and forms the basis of an algorithm developed by the author for finding D-optimal plans for models of incomplete rank in nonsymmetric design regions. The D-efficiency of designs concentrated at equidistant points was investigated.

Conservative method for vertical electrooculogram attenuation based on local suppression of ongoing EEG artifact templates.

Eye movement during blinking can be a significant artifact in Event-Related Potentials (ERP) analysis. Blinks produce a positive potential in the vertical electrooculogram (VEOG), spreading towards the posterior direction. Two methods are frequently used to suppress VEOGs: linear regression to subtract the VEOG signal from the electroencephalogram (EEG) and Independent Component Analysis (ICA). However, some information is lost in both. The present algorithm (1) statistically identifies the position of VEOGs in the frontopolar channels; (2) performs EEG averaging for each channel, which results in 'blink templates'; (3) subtracts each template from the respective EEG at each VEOG position, only when the linear correlation index between the template and the segment is greater than a chosen threshold L. The signals from twenty subjects were acquired using a behavioral test and were treated using FilterBlink for subsequent ERP analysis. A model was designed to test the method for each subject using twenty copies of the EEG signal from the subject's mid-central channel (with nearly no VEOG) representing the EEG channels and their respective blink templates. At the same 200 equidistant time points (marks), a signal (2.5 sinusoidal cycles at 1050 ms emulating an ERP) was mixed with each model channel and the respective blink template of that channel, between 500 to 1200 ms after each mark. According to the model, VEOGs interfered with both ERPs and the ongoing EEG, mainly on the anterior medial leads, and no significant effect was observed on the mid-central channel (Cz). FilterBlink recovered approximately 90% (Fp1) to 98% (Fz) of the original ERP and EEG signals for L = 0.1. The method reduced the VEOG effect on the EEG after ERP and blink-artifact averaging in analyzing real signals. The method is straightforward and effective for VEOG attenuation without significant distortion in the EEG signal and embedded ERPs.

Integration of AWEI and Otsu Threshold Algorithms for Maritime Boundary Delimitation: A Case Study of the Russia-Ukraine Conflict in the Sea of Azov

Since the Soviet Union dissolved in 1991, Russia and Ukraine, newly independent, face complexities concerning the legal status and demarcation of the Sea of Azov. Spanning approximately 37,600 km2 with a maximum depth of 14 meters, this sea holds pivotal resources such as fish, gas, and oil, serving as a significant dividing point between these nations. Maritime boundary delineation, often set at 12 nautical miles from the baseline, is complex due to the sea's intricate coastline and small islands. Some coastal areas have distances less than 24 nautical miles, causing boundary overlaps. Russia and Ukraine have cited UNCLOS Article 298, exempting UNCLOS dispute resolution for the Sea of Azov's demarcation. This study aims to assess the AWEI and Otsu thresholding algorithms' efficacy in defining the maritime boundary between Russia and Ukraine in the Sea of Azov, utilizing 'LANDSAT/LC08/C02/T1_L2' data. It also aims to comprehend the geopolitical and conflict resolution implications of delineating maritime boundaries aligned with UNCLOS 1982 for both countries and wider regions. The AWEI algorithm consistently maps coastlines, while Otsu thresholding facilitates automated image segmentation, yielding 117 base points covering 13,331 km2 (Russia) and 21,749 km2 (Ukraine) within the EEZ, based on equidistant and median base point analysis.

Corpus callosum damage in PSP and unsteady PD patients: A multimodal MRI study

IntroductionPostural instability (PI) is a common disabling symptom in Parkinson’s disease (PD) patients, but the brain alterations underlying this sign are not fully understood yet. This study aimed to investigate the association between PI and callosal damage in PD and progressive supranuclear palsy (PSP) patients, using multimodal MR imaging. MethodsOne-hundred and two PD patients stratified according to the presence/absence of PI (PD-steady N=58; PD-unsteady N=44), 69 PSP patients, and 38 healthy controls (HC) underwent structural and diffusion 3T brain MRI. Thickness, fractional anisotropy (FA) and mean diffusivity (MD) were calculated over 50 equidistant points covering the whole midsagittal profile of the corpus callosum (CC) and compared among groups. Associations between imaging metrics and postural instability score were investigated using linear regression. ResultsBoth PSP and PD-unsteady patient groups showed CC involvement in comparison with HC, while no difference was found between PD-steady patients and controls. The CC damage was more severe and widespread in PSP than in PD patients. The CC genu was the regions most damaged in PD-unsteady patients compared with PD-steady patients, showing significant microstructural alterations of MD and FA metrics. Linear regression analysis pointed at the MD in the CC genu as the main contributor to PI among the considered MRI metrics. ConclusionThis study identified callosal microstructural alterations associated with PI in unsteady PD and PSP patients, which provide new insights on PI pathophysiology and might serve as imaging biomarkers for assessing postural instability progression and treatment response.

Mathematical Derivations of Actuarial Present Value for the Fully Continuous Whole Life Assurances from the Theoretical Market Price

Many current mortality tables are computationally Makehamised but technically devoid of continuous key life table functions such as and because of the underlying sophisticated mortality functions and the complex methods of computation which usually do not incorporate the market price. The computationally advanced Moore’s model, which does not endorse the market pricing mechanisms offers one of the most complex analytical results that seems not user friendly in actuarial literature. As a result of the Moore’s complexity, we offer the Gradshteyn and Ryzhik’s analytic integral as an alternative solution to examine the contingency issues involving the estimation of actuarial present values of the continuous whole life annuities. In this study, the objective are to (i) estimate the parameters of GM (1,2) through the method of equidistant points according to the natural order of human age (ii) Apply the mean value theorem to construct the survival probability function under the framework of policy modifications (iii) Develop a closed form pricing formula for the continuous whole life annuity and continuous whole life insurance. The Gradshteyn and Ryzhik’s analytic integral has eliminated the Moore’s complexities associated with symbolic computations such that the continuity assumption applied allows us to compute the continuous life annuity with expedience. Computational evidence further shows that the continuous life annuity reduces with age confirming that life annuities is a decreasing function.