Histological and morphological development of the prepuce from birth to prepubertal age.

PURPOSE: To study the histological changes of the preputial tissue from birth to prepubertal age in order to define unnoticed morphological changes. MATERIALS AND METHODS: Prepuce samples were obtained from 79 healthy boys who underwent routine ritual circumcision. Specimens were divided into six groups according to the boys' age: newborn, 0-1 year of age, 2-3 years of age, 4-5 years of age, 6-7 years of age, and 8-9 years of age. Histologic analysis of the specimens was performed by H&E, Masson's trichrome, Verhoeff-Von Gieson, immunohistochemical staining. RESULTS: Microscopic examinations showed that average epithelial thickness increased after the neonatal period (p=0.001). When collagen fiber density was evaluated, no significant differences between groups were found (p=0.083). When the elastic fibers in the dermis were evaluated, it was determined that the number and thickness of elastic fibers increased with age. Immunohistochemical examinations showed that the number of peripheral nerves marked with S100 was lower in the neonatal period than at other ages (p=0.048). When the vessels marked with CD105 antibody were counted, there was no significant difference between the groups (p=0.078). CONCLUSIONS: This is the first study to examine the age-related structure of connective tissue elements in the foreskin. Our results showed that the prepuce's prepubertal maturation process is continuous, and the first 2 years of life are appropriate not only in relation to the physiological effects of age but also the optimum structural changes for wound healing, such as vessel diameter, epithelium thickness, peripheral nerve count.

Are lower urinary tract conditions more common in children with sleep bruxism?

INTRODUCTION: Sleep bruxism is a parasomnia caused by rhythmic and non-rhythmic activity of the masticatory muscles during sleep. Prevalence of sleep bruxism is reported up to 40.6% in the literature. Sleep bruxism is a multifactorial issue and associated with multiple dental complications, sleep-related disorders, and psychosocial problems. We aimed to investigate if children with sleep bruxism suffer more from lower urinary tract conditions. MATERIALS AND METHODS: Prospectively 128 children were included in this study. Sixty-four children constituted in the bruxism group and 64 children constituted in the control group. Children who admitted to the pediatric dentistry clinic with bruxism symptoms were recruited in the bruxism group. Control group constituted of consecutive 64 children who admitted to the pediatric dentistry clinic for routine dental examination. Parents were asked to fill out a questionnaire including Dysfunctional Voiding and Incontinence Scoring System (DVISS) form. Children's demographic data, presence of urinary frequency, presence of urgency, behaviour of voiding postponement, presence of daytime urinary incontinence, presence of enuresis nocturna, presence of fecal incontinence, presence of constipation, status of circumcision, and presence of bruxism related symptoms were recorded. Children with a DVISS score above 8 were considered to have functional voiding disorder. All children underwent a dental examination. RESULTS: The mean age of children was 73.3 ± 26.9 months. For all children (n = 128), the girl to boy ratio was 40:88. Mean DVISS score was 2.5 ± 3.8 and the mean QOL score was 0.1 ± 0.4 for all children. Eight (6.3%) children were found to have functional voiding disorder based on the DVISS score. There was no statistically significant difference for any lower urinary tract condition between the bruxism group and the control group (Table). Children with bruxism significantly had more tooth wear and masseter muscle hypertrophy (<0.001 and < 0.05). DISCUSSION: Sleep bruxism has been linked to a number of health issues including dental, systemic and psychosocial problems. Tooth wears, fatigue/pain in chewing muscles, gum recession, facial pain, masseter muscle hypertrophy and temporomandibular joint damage are the main complications of bruxism. Moreover, bruxism has been associated with systemic diseases and sypmtoms like asthma, respiratory illnesses, enuresis nocturna, anxiety, and stress. CONCLUSIONS: Children with sleep bruxism suffer more from tooth wear, masseter muscle hypertrophy, and regional pain over the jaw. Additionally morning fatigue, relationship issues, and respiratory illnesses are more common in bruxist children. Lower urinary tract conditions are not more frequent in children with sleep bruxism.

Patch Textures: Hardware Support for Mesh Colors.

Mesh Colors provide an effective alternative to standard texture mapping. They significantly simplify the asset production pipeline by removing the need for defining a mapping and eliminate rendering artifacts due to seams. This article addresses the problem that using Mesh Colors for real-time rendering has not been practical, due to the absence of hardware support. We show that it is possible to provide full hardware texture filtering support for Mesh Colors with minimal changes to existing GPUs by introducing a hardware-friendly representation for Mesh Colors that we call Patch Textures, which can have quadrilateral or triangular topology. We discuss the hardware modifications needed for storing and filtering Patch Textures, including anisotropic filtering. This article extends our previous work by discussing and comparing patch edge-handling approaches, including an option for sampling the textures of neighboring patches using an adjacency map. We also provide extensive discussions regarding data duplication, a partial implementation present in existing hardware, and the difficulties with providing a similar hardware support for Ptex.

Mach-RT: A Many Chip Architecture for High Performance Ray Tracing.

Data movement, particularly access to the main memory, has been the bottleneck of most computing problems. Ray tracing is no exception. We propose an unconventional solution that combines a ray ordering scheme that minimizes access to the scene data with a large on-chip buffer acting as near-compute storage that is spread over multiple chips. We demonstrate the effectiveness of our approach by introducing Mach-RT (Many chip - Ray Tracing), a new hardware architecture for accelerating ray tracing. Extending the concept of dual streaming, we optimize the main memory accesses to a level that allows the same memory system to service multiple processor chips at the same time. While a multiple chip solution might seem to imply increased energy consumption as well, because of the reduced memory traffic we are able to demonstrate, performance increases while maintaining reasonable energy usage compared to academic and commercial architectures. This article extends our previous work E. Vasiou, K. Shkurko, E. Brunvand, and C. Yuksel, "Mach-RT: A many chip architecture for high-performance ray tracing," in Proc. High-Perform. Graph. Conf., 2019 with design space exploration of the L3 cache size, more detailed evaluation of energy and memory performance, a discussion of energy delay product, and a brief exploration of boards with 16 chips. We also introduce new treelet enqueueing logic for the predictive scheduler.

Wearable 3D Machine Knitting: Automatic Generation of Shaped Knit Sheets to Cover Real-World Objects.

Knitting can efficiently fabricate stretchable and durable soft surfaces. These surfaces are often designed to be worn on solid objects as covers, garments, and accessories. Given a 3D model, we consider a knit for it wearable if the knit not only reproduces the shape of the 3D model but also can be put on and taken off from the model without deforming the model. This "wearability" places additional constraints on surface design and fabrication, which existing machine knitting approaches do not take into account. We introduce the first practical automatic pipeline to generate knit designs that are both wearable and machine knittable. Our pipeline handles knittability and wearability with two separate modules that run in parallel. Specifically, given a 3D object and its corresponding 3D garment surface, our approach first converts the garment surface into a topological disc by introducing a set of cuts. The resulting cut surface is then fed into a physically-based unclothing simulation module to ensure the garment's wearability over the object. The unclothing simulation determines which of the previously introduced cuts could be sewn permanently without impacting wearability. Concurrently, the cut surface is converted into an anisotropic stitch mesh. Then, our novel, stochastic, any-time flat-knitting scheduler generates fabrication instructions for an industrial knitting machine. Finally, we fabricate the garment and manually assemble it into one complete covering worn by the target object. We demonstrate our method's robustness and knitting efficiency by fabricating models with various topological and geometric complexities. Further, we show that our method can be incorporated into a knitting design tool for creating knitted garments with customized patterns.

Particle Merging-and-Splitting.

Robustly handling collisions between individual particles in a large particle-based simulation has been a challenging problem. We introduce particle merging-and-splitting, a simple scheme for robustly handling collisions between particles that prevents inter-penetrations of separate objects without introducing numerical instabilities. This scheme merges colliding particles at the beginning of the time-step and then splits them at the end of the time-step. Thus, collisions last for the duration of a time-step, allowing neighboring particles of the colliding particles to influence each other. We show that our merging-and-splitting method is effective in robustly handling collisions and avoiding penetrations in particle-based simulations. We also show how our merging-and-splitting approach can be used for coupling different simulation systems using different and otherwise incompatible integrators. We present simulation tests involving complex solid-fluid interactions, including solid fractures generated by fluid interactions.

Ability of ESWL nomograms to predict stone-free rate in children.

INTRODUCTION: We aimed to evaluate whether the pediatric extracorporeal shock wave lithotripsy (ESWL) nomograms can predict stone-free status in children effectively and whether they are applicable to our series. We hypothesize that two current nomograms predicting successful treatment with ESWL in pediatric patients are valid. STUDY DESIGN: We evaluated 415 renal units (children <18 years) with eligible data who received ESWL treatment for upper urinary tract stones. Children's age, gender, stone size, stone surface area, stone location and history of previous intervention were recorded. Children with no residual fragments after ESWL treatment were designated as stone-free. The nomograms described by Dogan and Onal were implemented to our series for the prediction of stone-free status. RESULTS: Mean age of children was 64.7 ± 57.2 months. Male to female ratio was 219:196.78.8% (327) of children had single stone. Mean stone size was 10.0 ± 3.7 mm and mean stone surface area was 380.0 ± 72.2 mm2. Our stone-free rate after single ESWL session was 52.5% (218/415). Mean residual stone size and stone surface area after single session was 6.4 ± 3.3 mm and 36.0 ± 44.2 mm2 respectively. There were no significant difference between stone-free children and children with residual fragments regarding gender, age and history of previous intervention. Mean stone size and stone surface area in stone-free children were lower and lower pole stones had the lowest stone-free rate (p < 0.05). Area under curve for Dogan and Onal nomogram were 0.628 and 0.580 respectively in ROC analysis (0.05). The agreement between Dogan and Onal score was moderate in our series. In multivariate analysis only stone surface area and Dogan score found to be independent predictors of stone-free status (p < 0.05). DISCUSSION: Only one study has assessed both nomograms in the literature. Both nomograms are reported to be independent predictors of stone free status. ROC analysis in our study revealed fair accuracy for both nomograms with higher area under curve for Dogan nomogram. Higher accuracy for both nomograms were reported by other authors. These nomograms offer practical data but more effective tools are needed to be developed for the prediction of stone-free status in pediatric ESWL. CONCLUSIONS: Stone size and stone surface area are associated with stone clearance. Dogan and Onal nomograms can be useful in prediction of stone-free status in children. Dogan nomogram is superior to Onal nomogram.

Stochastic Lightcuts for Sampling Many Lights.

We introduce stochastic lightcuts by combining the lighting approximation of lightcuts with stochastic sampling for efficiently rendering scenes with a large number of light sources. Our stochastic lightcuts method entirely eliminates the sampling correlation of lightcuts and replaces it with noise. To minimize this noise, we present a robust hierarchical sampling strategy, combining the benefits of importance sampling, adaptive sampling, and stratified sampling. Our approach also provides temporally stable results and lifts any restrictions on the light types that can be approximated with lightcuts. We present examples of using stochastic lightcuts with path tracing and indirect illumination with virtual lights, achieving more than an order of magnitude faster render times than lightcuts by effectively approximating direct illumination using a small number of light samples, in addition to providing temporal stability. Our comparisons to other stochastic sampling techniques demonstrate that we provide superior sampling quality that matches and improves the excellent convergence rates of the lightcuts approach.

Real-Time Cloth Rendering with Fiber-Level Detail.

Modeling cloth with fiber-level geometry can produce highly realistic details. However, rendering fiber-level cloth models not only has a high memory cost but it also has a high computation cost even for offline rendering applications. In this paper we present a real-time fiber-level cloth rendering method for current GPUs. Our method procedurally generates fiber-level geometric details on-the-fly using yarn-level control points for minimizing the data transfer to the GPU. We also reduce the rasterization operations by collectively representing the fibers near the center of each ply that form the yarn structure. Moreover, we employ a level-of-detail strategy to minimize or completely eliminate the generation of fiber-level geometry that would have little or no impact on the final rendered image. Furthermore, we introduce a simple self-shadow computation method that allows lighting with self-shadows using relatively low-resolution shadow maps. We also provide a simple distance-based ambient occlusion approximation as well as an ambient illumination precomputation approach, both of which account for fiber-level self-occlusion of yarn. Finally, we discuss how to use a physical-based shading model with our fiber-level cloth rendering method and how to handle cloth animations with temporal coherency. We demonstrate the effectiveness of our approach by comparing our simplified fiber geometry to procedurally generated references and display knitwear containing more than a hundred million individual fiber curves at real-time frame rates with shadows and ambient occlusion.

Time Interval Ray Tracing for Motion Blur.

We introduce a new motion blur computation method for ray tracing that provides an analytical approximation of motion blurred visibility per ray. Rather than relying on timestamped rays and Monte Carlo sampling to resolve the motion blur, we associate a time interval with rays and directly evaluate when and where each ray intersects with animated object faces. Based on our simplifications, the volume swept by each animated face is represented using a triangulation of the surface of this volume. Thus, we can resolve motion blur through ray intersections with stationary triangles, and we can use any standard ray tracing acceleration structure without modifications to account for the time dimension. Rays are intersected with these triangles to analytically determine the time interval and positions of the intersections with the moving objects. Furthermore, we explain an adaptive strategy to efficiently shade the intersection intervals. As a result, we can produce noise-free motion blur for both primary and secondary rays. We also provide a general framework for emulating various camera shutter mechanisms and an artistic modification that amplifies the visibility of moving objects for emphasizing the motion in videos or static images.

Uncertainty Visualization by Representative Sampling from Prediction Ensembles.

Data ensembles are often used to infer statistics to be used for a summary display of an uncertain prediction. In a spatial context, these summary displays have the drawback that when uncertainty is encoded via a spatial spread, display glyph area increases in size with prediction uncertainty. This increase can be easily confounded with an increase in the size, strength or other attribute of the phenomenon being presented. We argue that by directly displaying a carefully chosen subset of a prediction ensemble, so that uncertainty is conveyed implicitly, such misinterpretations can be avoided. Since such a display does not require uncertainty annotation, an information channel remains available for encoding additional information about the prediction. We demonstrate these points in the context of hurricane prediction visualizations, showing how we avoid occlusion of selected ensemble elements while preserving the spatial statistics of the original ensemble, and how an explicit encoding of uncertainty can also be constructed from such a selection. We conclude with the results of a cognitive experiment demonstrating that the approach can be used to construct storm prediction displays that significantly reduce the confounding of uncertainty with storm size, and thus improve viewers' ability to estimate potential for storm damage.

Does structured withdrawal of desmopressin improve relapse rates in patients with monosymptomatic enuresis?

PURPOSE: Relapse after cessation of desmopressin is an important problem in treating patients with enuresis. Structured withdrawal of desmopressin tablets has been shown to decrease relapse rates. However, scientific data are lacking on the structured withdrawal of the fast melting oral formulation of desmopressin. We compared relapse rates of structured withdrawal using placebo and direct cessation in a population of patients with enuresis who were desmopressin responders. MATERIALS AND METHODS: Patients diagnosed with enuresis and responding to desmopressin from 13 different centers were involved in the study. Patients were randomized into 4 groups. Two different structured withdrawal strategies were compared to placebo and direct withdrawal. Sample size was estimated as 240 (60 patients in each group), with a power of 0.80 and an effect size of 30%. Randomization was performed using NCSS statistical software (NCSS, Kaysville, Utah) from a single center. The relapse rates of the groups were compared using chi-square testing. Logistic regression analysis was performed to define the independent factors having an effect on relapse rates. RESULTS: Desmopressin treatment was initiated in 421 patients, and 259 patients were eligible for randomization. Relapse rates were 39 (1%) and 42 (4%) for the structured withdrawal groups, which were significantly less than for direct withdrawal (55, 3%) and placebo (53, 1%). Logistic regression analysis revealed that initial effective dose of 240 µcg, greater number of wet nights before treatment and nonstructured withdrawal were associated with higher relapse rates. CONCLUSIONS: We found that structured withdrawal with the fast melting oral formulation of desmopressin results in decreased relapse rates. Application of a structured withdrawal program was also an independent factor associated with reduced relapse rates, together with lower initial effective dose and number of wet nights per week. Relapse after cessation of desmopressin is an important problem, and in this study structured withdrawal was observed to be associated with decreased relapse rates compared to placebo and direct withdrawal.

Visualization of fibrous and thread-like data.

Thread-like structures are becoming more common in modern volumetric data sets as our ability to image vascular and neural tissue at higher resolutions improves. The thread-like structures of neurons and micro-vessels pose a unique problem in visualization since they tend to be densely packed in small volumes of tissue. This makes it difficult for an observer to interpret useful patterns from the data or trace individual fibers. In this paper we describe several methods for dealing with large amounts of thread-like data, such as data sets collected using Knife-Edge Scanning Microscopy (KESM) and Serial Block-Face Scanning Electron Microscopy (SBF-SEM). These methods allow us to collect volumetric data from embedded samples of whole-brain tissue. The neuronal and microvascular data that we acquire consists of thin, branching structures extending over very large regions. Traditional visualization schemes are not sufficient to make sense of the large, dense, complex structures encountered. In this paper, we address three methods to allow a user to explore a fiber network effectively. We describe interactive techniques for rendering large sets of neurons using self-orienting surfaces implemented on the GPU. We also present techniques for rendering fiber networks in a way that provides useful information about flow and orientation. Third, a global illumination framework is used to create high-quality visualizations that emphasize the underlying fiber structure. Implementation details, performance, and advantages and disadvantages of each approach are discussed.