Primary Rays Research Articles

Processing time and precision of aging structures for Bighead Carp and Silver Carp in the lower Red River catchment in the southern Great Plains

AbstractObjectivePopulation demographics of invasive species are commonly evaluated to better develop management actions that are useful for reducing their abundance or controlling the population. Bighead Carp Hypophthalmichthys nobilis and Silver Carp H. molitrix are emblematic invaders in the United States, where they continue to expand their range. There is currently no consensus about which hard structure from these species is best for age estimation. Our study objective was to compare the processing time and precision of five hard structures used for age estimation of both species.MethodsWe sampled fish in the lower Red River catchment of Oklahoma, Arkansas, and Texas during summer and autumn 2021–2022 and removed the lapillus otolith, left primary pectoral fin ray, postcleithrum, urohyal bone, and anterior‐most pterygiophore of the dorsal fin from both Bighead and Silver carp. The structures (n = 1204) were either embedded in epoxy or thin‐sectioned and mounted on slides. Two readers estimated the age of the fish by using each structure and came to a consensus. Processing time was recorded from the onset of laboratory processing to the termination of polishing the cross sections for age estimation.ResultProcessing of otoliths was comparable to or faster than processing of the other structures and resulted in the highest between‐reader agreement. The lowest coefficients of variation in age estimation were represented using lapillus otoliths for Bighead Carp and postcleithra for Silver Carp. Our age bias plots indicated that all other structures underestimated age relative to the lapillus otoliths.ConclusionOur results indicated that using lapillus otoliths for age estimation of these species would have the highest between‐reader agreement and would incur no additional laboratory processing time. However, validation is needed to assess whether lapillus otoliths correctly age these species. From a management perspective, use of this structure would facilitate improved population comparisons.

Research on Distortion Control in Off-Axis Three-Mirror Astronomical Telescope Systems

With off-axis reflection systems with specific distortion values serving as objectives or collimators, it is possible to compensate and correct for spectral line bending in spectroscopic instruments. However, there is limited research on the precise control of distortion, which poses particular challenges in large field-of-view optical systems. This paper presents a method for controlling distortion in off-axis reflection systems. Based on Seidel aberration theory and the relationship between distortion wavefront error and primary ray error, we construct objective functions with structural constraints and aberration constraints. The initial structure with specific distortion values is then solved using a differential evolution algorithm. The effectiveness and reliability of this method are verified through the design of an off-axis three-reflection system. The method provided in this study facilitates the design of remote sensing instruments.

The Effect of Therapeutic Approaches on Hallux Valgus Deformity.

Hallux valgus (HV) is a relatively frequent disease caused by a complicated structural malformation of the primary ray. The bunion or middle projection generated by the hallux's lateral displacement and pronation is merely one element of the three-dimensional abnormality. HV may trigger severe discomfort and affect joint kinematics. The specific kinematic cause is still unknown. Female age, gender, restrictive footwear, and heritage are risk indicators. HV frequently coexists along metatarsal adducts, equines contracture, hammertoe imperfection, and pes planus. HV is a frequent foot ailment with multiple, complicated, unknown etiology and course. HV has a preference for females. It is an ongoing condition for which there is no known treatment to reduce or prevent improvement.Fibrodysplasia ossificans progressiva (FOP) is distinguished by hereditary symmetrical HVdeformities or symptoms that begin heterotopic calcification that is either idiopathic or caused by trauma, such as subcutaneous immunizations. Localized heterotopic calcification may be preceded by aggravating, recurring soft-tissue enlargements (flare-ups). Heterotopic calcification may happen anywhere; however, it most commonly impacts locations near the axial bone structure during the early/mild phases until advancing to the appendicular skeleton. As an effect of calcification affecting the flexibility of the joints, it might cause limitations in motion.The initial line of therapy focuses on non-surgical methods including night splinting, orthotics, and larger shoes. The next suggested line of action is surgical intervention if conservative therapy fails. Patients have good postoperative tolerance, and bone union often happens six to seven weeks after surgery. Stretching exercises help to restore function by extending shortened soft tissue and restoring range of motion (ROM). The goal of joint mobilization, a form of manual treatment method, is to extend the ligament, the soft tissue surrounding the limited joint, and the restricting joint capsule by applying modest amplitude passive movement to the joint components.

Ray resection in pediatric population after trauma injuries.

The aim of this study is to assess the functional, emotional, and social adaptation of pediatric patients submitted to a hand ray resection to treat a traumatic hand injury. Retrospective study of pediatric patients undergoing hand ray resection, in the period 2013-2022, performed in two hospital institutions. Inclusion criteria: age less than 18 years, primary/secondary resection due to traumatic etiology and follow-up time of more than 1 year. Data concerning demographic information, lesion location, traumatic mechanism and surgical description were collected. Functional outcomes (QuickDASH Score), social and emotional integration (PEDSQL) and satisfaction were evaluated. Seven patients were included, with male predominance (n = 4) and the right side was the most affected (n = 5). Median age at the time of surgery was 10 years (2-15). Primary ray resection, without previous revascularization, was performed in three patients. Secondary ray resection was performed in four patients. Three patients with an unsuccessful revascularization procedure attempt another patient with a sequela with severe deformity. All patients presented a good adaptation to daily living activities, with good pinch and grip function. The median follow-up was 4 years (min:1; max:9). The scores were collected on six out of seven patients. Median QuickDASH score of 14 (min:11; max:22), and PEDSQL[physical] of 95.31 (min:78.13; max:100) and PEDSQL[social] of 93.47 (min:66.3; max:100). Hand ray resection is a rare procedure in pediatric age and usually difficult for patients and parents to accept. However, it is a useful and safe technique that allows for an improvement in overall hand function and psychosocial readaptation in specific and selected cases. Level of evidence: Level of evidence IV - case series.

Locally-Adaptive Level-of-Detail for Hardware-Accelerated Ray Tracing

We introduce an adaptive level-of-detail technique for ray tracing triangle meshes that aims to reduce the memory bandwidth used during ray traversal, which can be the bottleneck for rendering time with large scenes and the primary consumer of energy. We propose a specific data structure for hierarchically representing triangle meshes, allowing localized decisions for the desired mesh resolution per ray. Starting with the lowest-resolution triangle mesh level, higher-resolution levels are generated by tessellating each triangle into four via splitting its edges with arbitrarily-placed vertices. We fit the resulting mesh hierarchy into a specialized acceleration structure to perform on-the-fly tessellation level selection during ray traversal. Our structure reduces both storage cost and data movement during rendering, which are the main consumers of energy. It also allows continuous transitions between detail levels, while locally adjusting the mesh resolution per ray and preserving watertightness. We present how this structure can be used with both primary and secondary rays for reflections and shadows, which can intersect with different tessellation levels, providing consistent results. We also propose specific hardware units to cover the cost of additional compute needed for level-of-detail operations. We evaluate our method using a cycle-accurate simulation of a custom ray tracing hardware architecture. Our results show that, as compared to traditional bounding volume hierarchies, our method can provide more than an order of magnitude reduction in energy use and render time, given sufficient computational resources.

A Research on the Anatomical and Ecological Characteristic of Onosma mollis DC. (Boraginaceae)

In this study, endemic Onosma mollis DC. it is aimed to examine the anatomical and ecological features of (Boraginaceae) plant in detail and to be compared with the other studies. According to the cross-sections, the root is secondary. Primary pith rays that 2-3 layered are observed. Epidermis is single-layered in stem transverse section. Eglandular hairs in the epidermis are simple, with one and two cells. Glandular hairs are capitate, digitate and with two cells. Just under the epidermis, 2-3 rows of collenchyma cells are formed. Both the upper and the lower surface of leaf is covered with numerous eglandular hairs. Eglandular hairs are 2-3 branched. Glandular hairs are of capitate, digitate and peltate type. The habitat of the O. mollis plant is mountain slopes, meadows, and prairies. The soil in which the species grows is clay and loamy. It is also classified as slightly alkaline, salty, calcareous, low phosphorus and high in potassium. According to its organic matter content, it is in the group of good humus soils.

Surface Field Analytical Solution of the Impedance Boundary Condition Circular Cylinder Canonical Problem

A surface field analytical solution of the impedance boundary condition circular cylinder canonical problem is contributed in the work at hand. The accurate representation of the primary ray contribution of the tangential surface magnetic field, of a tangential magnetic current excited relative electromagnetic structure, is given via series expansion in powers of the normalized surface impedance. Furthermore, each term in the series is represented as series of the inverse of the cylinder radius. This is achieved by approximating the Hankel functions by a uniform asymptotic expansion within the spectral integral representation of the relevant Green’s function. All the resulted integrals are evaluated analytically in an exact fashion. and, thus, the final process entails only summations and differentiations. The attained formulas are valid both within and outside the paraxial region. Validity of the contributed analytical solution is provided by successful comparison with published results.

Diffraction- and Reflection-Aware Multiple Sound Source Localization

In this article, we present a novel localization method for multiple sources in indoor environments. Our approach can estimate different propagation paths, including the reflection and diffraction paths of sound waves based on a backward ray tracing technique. To estimate diffraction propagation paths, we combine a ray tracing algorithm with a uniform theory of diffraction model by exploiting the diffraction properties as propagation paths bend around the wedges of obstacles. We reconstruct the 3-D environments and wedges of obstacles in the precomputation phase and utilize these outcomes to generate primary, reflection, and diffraction acoustic rays in the runtime phase. We localize multiple sources when identifying the convergence regions of these acoustic rays based on Monte Carlo localization (MCL). Our approach supports not only stationary but also moving sources of human speech and clapping sounds. Our approach can also handle nonline-of-sight (NLOS) sources and distinguish between active and inactive source states. We evaluated and analyzed our algorithm in multiple scenarios containing obstacles and NLOS sources. Our approach can localize moving sources with the average of distance errors of 0.65 and 0.74 m in single and multiple source cases, respectively, in rooms, 7 m by 7 m in size with a height of 3 m; errors are measured according to the L2 distance between the estimated and actual source positions. We observed a 130% improvement of the localization accuracy over the prior work (J.-M. Valin <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">et al.</i> ).

A Look at the Course and Management of Non-Traumatic Upper Extremity Amputation

Objectives Amputation is a major source of morbidity and mortality. Non-traumatic amputations of the upper extremity are less common, and less well-characterized, than the lower extremity. We hypothesize that upper extremity amputations are often associated with multiple returns to the operating room. Methods Twenty-five patients were identified that underwent primary or revision ray or phalangeal amputations for vascular/infectious indications. Chart review was utilized to gather information on additional amputations and demographic information. These groups were compared via chi-squared analysis assuming equal distributions of operations would be present between groups. Results Of the patients with infectious and/or vascular amputations, 56% had a subsequent amputation. Additionally, 23 irrigation and debridement\’s (I and D) were performed before resorting to amputation with 6 patients requiring multiple I and Ds. Post-amputation, 3 patients required I and D, 7 revision amputations at higher levels, 8 amputations of additional ipsilateral digits, and 4 amputations of contralateral digits were performed. After initial amputation, there is a 76% chance of undergoing an additional operation and/or amputation of the upper extremity. A subgroup of these patients with diabetes showed statistically significant increases in ipsilateral amputations following initial amputation. Conclusions Our study shows that patients undergoing digit amputation for nontraumatic indications may require additional upper extremity operations following initial amputation. Subsequent revision amputation at a higher level is common and suggests that more aggressive early amputation may be warranted in these patients. Specifically, diabetic patients are at significantly increased risk of requiring additional digit amputations and may benefit from more aggressive initial surgery at time of presentation.

Form and function of labral fan-ray microtrichia and posterior proleg barbs in Neotropical black flies larvae (Diptera: Simuliidae)

The microtrichia of the labral fan primary rays, considered as the finest structure of the larval filter mechanism in Simuliidae, and the posterior proleg hooks, a structure used for substrate attachment, were describe using Scanning Electron Microscopy for the first time in 14 Neotropical species of black flies. Four patterns of primary rays microtrichia and two types of hooks barbs disposition were found. The present study provides new morphological information for Neotropical black fly species, compares it with previous information for worldwide species. Also, shows that the presence of posterior proleg hooks barbs is common among black fly species, that these barbs are not related with the larval habitat or with the primary ray microtrichia pattern, and that flow conditions may influence the last-instar larvae microtrichial patterns, at least in most of the Neotropical species studied here.

Mathematical algorithm model of absolute dose in radiotherapy

A algorithm of obtaining absolute dose at each tissue depth only by the mathematical calculation of formula is reported. The algorithm is based on integrating the energy flux of the electron generated by X-ray in the range of irradiation field, and the energy spectrum of ray and the secondary scattered ray are considered in this process. In this algorithm, the water phantom in the irradiation field is divided into several thin layers, and the energy flux of the electrons generated by interaction between the ray and thin layer reaching the calculation point is calculated. Finally, the absolute dose of the calculation point can be obtained by accumulating the energy flux contribution of all thin layers. For the X-ray with continuous energy spectrum, the expected mass attenuation coefficient is calculated for obtaining the photon flux at each depth in this process. The absolute dose calculated by this algorithm is verified by Monte Carlo simulation, and the difference between the algorithm and simulation is compensated for by a dose function about multiple scattering photons, and the function shows fast descent and then slow ascent. It is found that the ratio of the dose caused by backscatter to the surface dose, and the relationship among forward scatter, backward scatter and primary ray, and the relationship between the dose and the depth of the secondary scattered rays show a trend of first rising and then declining, and the depth of the peak value deviates from the position of the thin layer. Three-dimensional energy spectra of the secondary photon and the secondary electron are also compared with each other, and the spectrum is a function of particle flux about particle energy and particle direction. From the perspective of Compton effect, the physical meanings of different positions in the three-dimensional energy spectrum of the two particles are explained. It is found that the difference between algorithm percentage depth dose and simulation percentage depth dose is similar to the difference between small irradiation field percentage depth dose and big irradiation field percentage depth dose from simulation, and it is verified that the difference between algorithm and simulation comes from the increase of scattered rays. Finally, the algorithm is applied to the dose calculation of non-uniform phantom, which can accurately reflect the dose distribution characteristics and have less error.

Features of the Use of Symbolic Calculations for Constructing Wave Field Local Asymptotics Using Catastrophe Theory

Base on symbol calculation a local asymptotic method is developed that describes the diffraction focusing of electromagnetic fields in the case when a family of primary (geometrooptical) and secondary (edge) rays form focusings of the cuspoid type A2 (wave catastrophe F4). Mathematical modeling of the unfolding coefficients and the traveling wave phase was performed. Explicit expressions for the parameters of unfolding are obtained.

Third-order derivative matrix of a skew ray with respect to the source ray vector at a flat boundary.

Our group recently showed that the Seidel primary ray aberration coefficients of an axis-symmetrical system can be accurately determined using the third-order Taylor series expansion of a skew ray R¯m on an image plane. This finding inspires us to determine the third-order derivative matrix of R¯m with respect to the vector X¯0 of the source ray, i.e., ∂R¯m3/∂X¯03, under reflection/refraction at a flat boundary. Finite difference methods using the second-order derivative matrix, ∂R¯m2/∂X¯02, require multiple rays to compute ∂R¯m3/∂X¯03 and suffer from cumulative rounding and truncation errors. By contrast, the present method is based on differential geometry. Thus, it provides a greater inherent accuracy and requires the tracing of just one ray. The proposed method facilitates the analytical investigation of the primary aberrations of an axis-symmetrical system and can be easily extended to determine the higher-order derivative matrices required to explore higher-order ray aberration coefficients.

Cinematic Rendering Technique in Adult Congenital Heart Disease

Abstract Cinematic rendering (CR) is a recently introduced 3D-visualization technique that generates photorealistic images with higher depth and shape perception than volume rendering (VR). In CR, each pixel of the rendering is generated by integration of the light scattered in all the directions along the primary light ray beam using a path-tracing method. CR has several potential applications in adult congenital heart disease (ACHD), particularly in the characterization of complex anomalies, assessment of relationship to adjacent structures and education. In this article, we review the principles of CR, compare it with VR and illustrate the applications in ACHD.

Seidel primary ray aberration coefficients for objects placed at finite and infinite distances.

In a recent study, the present group proposed a methodology for determining the Seidel primary aberration coefficients in terms of the polar coordinates of the source ray for an object placed at a finite distance from the entrance pupil [P. D. Lin and R. B. Johns, Opt. Express27, 19712 (2019)]. However, that model will be failed for an object placed at infinity. It is also found that all existing works in the optics field use in-plane coordinates of the entrance pupil (i.e., Xa and ya) to investigate the aberration coefficients. Accordingly, the present study revisits the problem once again using a Taylor series expansion of a ray in terms of the object height h0 and coordinates [xaya]T. In the proposed methodology, the independent variables of the optical system are identified and the intercept coordinates of the skew ray on the image plane are then expanded with respect to these variables. It is shown that the expressions of the Seidel primary aberration coefficients are very concise and the corresponding numerical results are in good agreement with those obtained from Zemax simulations. Notably, the method proposed in this study is also valid for objects lying at infinity provided that the collimated rays emerging from the object are incident on the entrance pupil. Moreover, the methodology can also be extended to have the numerical values of the higher-order ray aberration coefficients for axis-symmetrical systems.

Description and characterization of the artisanal elasmobranch fishery on Guatemala's Caribbean coast.

Small-scale shark and ray fisheries are conducted throughout Central America’s Caribbean coast. Yet, there is limited information regarding catch composition and diversity of these fisheries, especially in Guatemala. Surveys of catch landings were conducted in two of Guatemala’s primary Caribbean coastal shark and ray fishing communities, El Quetzalito and Livingston, between January 2015 and July 2017. Biological data from 688 landed chondrichthyans were collected, with 31 species (24 sharks, six rays and one chimaera) identified. The four most frequently captured species included Carcharhinus falciformis (30.2%), Sphyrna lewini (12.7%), Hypanus guttatus (12%) and Rhizoprionodon spp. (6.7%). Landed sharks contained most size classes with a high proportion of juveniles of species with low productivity. The large-bodied species C. falciformis and S. lewini were often recorded at sizes below known maturity; 96.6% and 85.1%, of the captured individuals were immature, respectively. This study can serve as a baseline to determine future trends in the elasmobranch fisheries conducted by Guatemala’s Caribbean coastal communities and support assessments on the persistence of the fisheries.

Indications, functional results and patient satisfaction after isolated second ray resection following traumatic injury: A retrospective review of 25 patients

Amputation of the second ray is a surgical treatment option when reconstruction and/or reimplantation fail. The aim of our study was to review the outcomes after transmetacarpal resection of the second ray following a post-traumatic injury and to assess indications, functional outcomes, and patient satisfaction. Between January 2003 and December 2013, 25 patients (6 women and 19 men with a mean age of 51 years) underwent transmetacarpal resection of their second ray after a post-traumatic injury. Sixteen patients were right-handed and 9 were left-handed. Injuries involved the dominant hand in 14 cases (60%). In order to differentiate patients with preserved index finger length preoperatively from those with a shorter, amputated index finger stump, patients were divided into 2 groups. Group 1 included those with an “intact finger” and Group 2 included patients with an “amputated stump”. Data collection, including patient satisfaction and functional outcomes, was performed at 83 months postoperative on average. Average length of follow-up was 7.0±1.0 years (range 5–12 years). Group 1 (intact finger) and 2 (amputated stump) included 15 and 10 patients, respectively. Six patients (24%) had primary ray amputation and 19 (76%) had secondary ray amputation. No surgical revision was necessary. In Group 1, the indications were purely functional in all but two cases, whereas aesthetic indications played a role in all patients in Group 2. The average total time off work was 3 months. There was no difference between Group 1 and 2 (P>0.05). However, patients with primary ray resection averaged 10 weeks of lost work compared to 17 weeks for secondary amputation. There was no functional difference between Groups 1 and 2. Scores for cosmetic appearance and patient satisfaction were higher in Group 2. In certain specific situations after complex hand trauma, transmetacarpal amputation of the second ray is indicated as soon as possible, in order to reduce the time off work. Patient satisfaction following this surgical procedure is high, especially in groups with amputated stumps. A 30% decrease in pinch and grip strength is the rule. No secondary surgery is normally required.

Evaluating the hierarchical, hygroscopic deformation of the Daucus carota umbel through structural characterization and mechanical analysis

Many physically immobile plants develop passive yet ingenious strategies for active seed dispersal through self-deformation in response to external stimuli, such as humidity. These hygroscopic deformations are usually driven by the internal heterogeneous architecture, which provides valuable, inspiring information for the development of novel actuating systems. The Daucus carota compound umbel is an interesting structure showing a distinct hygroscopic deformation that operates at hierarchical levels among these plants. Here, we investigate the structure of the primary and secondary rays of the umbel associated with their deformation through mechanical analyses. We reveal that through controlling both the cellulose microfibril angle (MFA) and lignification, the multi-level bending behavior of the umbel is achieved, which contributes to efficient seed protection and dispersal. The primary rays generally show more significant bending curvature changes than the secondary rays, and within each level, the outer rays exhibit a larger motion amplitude than the middle and inner rays. Mechanical testing and theoretical analysis support that adjusting the lignin content within the ray structure compensates for the effect of the small differences in cellulose MFA on its bending behavior, which contributes to the overall hygroscopic deformation. Findings also show that the primary outer ray can generate reaction forces that are more than 700 times its weight, which is higher than that for the pine cone scales. The new insights from this work are instructive for bioinspired designs of complex, self-deforming structures and devices. Statement of SignificanceThe carrot (Daucus carota) compound umbels exhibit a unique hierarchical, hygroscopic deformation for seed dispersal among immobile plants. In this work, we elucidate that the multi-level bending behavior of the umbel is achieved through manipulating the cellulose microfibril angle (MFA) and lignification of the primary and secondary rays for the first time. We also discover that adjusting the degree of lignification compensates for the effect of small cellulose MFA differences on the bending behavior theoretically and experimentally. The primary outer rays deform in a highly efficient manner, in which reactions forces about more than 700 times its weight are generated. The findings presented are instructive for bioinspired designs of complex, self-deforming structures and devices.

Seidel aberration coefficients: an alternative computational method.

An alternative method to compute Seidel aberrations is presented that utilizes real pseudoparaxial skew rays traveling through a rotationally-symmetric lens system as a Taylor series expansion in terms of object height and ray-direction spherical coordinates. Expressions for defocus, lateral magnification, and Seidel primary ray aberration coefficients are obtained in terms of numerically-determined higher-order partial derivatives of rays which are proximate to the optical axis. In contrast to commonly used methods, the new form of the aberration coefficients is related to unit entrance pupil radius and unit object height. The proposed methodology can be extended to derive higher-order ray aberration coefficients.

RayCaching: Amortized Isosurface Rendering for Virtual Reality

AbstractReal‐time virtual reality requires efficient rendering methods to deal with high‐ resolution stereoscopic displays and low latency head‐tracking. Our proposed RayCaching method renders isosurfaces of large volume datasets by amortizing raycasting over several frames and caching primary rays as small bricks that can be efficiently rasterized. An occupancy map in form of a clipmap provides level of detail and ensures that only bricks corresponding to visible points on the isosurface are being cached and rendered. Hard shadows and ambient occlusion from secondary rays are also accumulated and stored in the cache. Our method supports real‐time isosurface rendering with dynamic isovalue and allows stereoscopic visualization and exploration of large volume datasets at framerates suitable for virtual reality applications.