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Commonly used image‐space layouts of shading points, such as used in deferred shading, are strictly view‐dependent, which restricts efficient caching and temporal amortization. In contrast, texture‐space layouts can represent shading on all surface points and can be tailored to the needs of a particular application. However, the best grouping of shading points—which we call a shading unit—in texture space remains unclear. Choices of shading unit granularity (how many primitives or pixels per unit) and in shading unit parametrization (how to assign texture coordinates to shading points) lead to different outcomes in terms of final image quality, overshading cost, and memory consumption. Among the possible choices, shading units consisting of larger groups of scene primitives, so‐called meshlets, remain unexplored as of yet. In this paper, we introduce a taxonomy for analyzing existing texture‐space shading methods based on the group size and parametrization of shading units. Furthermore, we introduce a novel texture‐space layout strategy that operates on large shading units: the meshlet shading atlas. We experimentally demonstrate that the meshlet shading atlas outperforms previous approaches in terms of image quality, run‐time performance and temporal upsampling for a given number of fragment shader invocations. The meshlet shading atlas lends itself to work together with popular cluster‐based rendering of meshes with high geometric detail. [ABSTRACT FROM AUTHOR]

The recent research explosion around implicit neural representations, such as NeRF, shows that there is immense potential for implicitly storing high‐quality scene and lighting information in compact neural networks. However, one major limitation preventing the use of NeRF in real‐time rendering applications is the prohibitive computational cost of excessive network evaluations along each view ray, requiring dozens of petaFLOPS. In this work, we bring compact neural representations closer to practical rendering of synthetic content in real‐time applications, such as games and virtual reality. We show that the number of samples required for each view ray can be significantly reduced when samples are placed around surfaces in the scene without compromising image quality. To this end, we propose a depth oracle network that predicts ray sample locations for each view ray with a single network evaluation. We show that using a classification network around logarithmically discretized and spherically warped depth values is essential to encode surface locations rather than directly estimating depth. The combination of these techniques leads to DONeRF, our compact dual network design with a depth oracle network as its first step and a locally sampled shading network for ray accumulation. With DONeRF, we reduce the inference costs by up to 48× compared to NeRF when conditioning on available ground truth depth information. Compared to concurrent acceleration methods for raymarching‐based neural representations, DONeRF does not require additional memory for explicit caching or acceleration structures, and can render interactively (20 frames per second) on a single GPU. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate inadvertent warming of the infusion syringe in four different types of electronic syringe pumps.Methods: Ambient temperature and syringe surface temperature were simultaneously measured by two electronic temperature probes in four different models of commercially available syringe pumps. Experiments were performed at an infusion rate of 1 ml h(-1) using both battery-operated and main power-operated pumps. Measurements were repeated four times with two pumps from each of the four syringe pump types at a room temperature of approximately 23 degrees C. Differences among the four syringe pump brands regarding ambient to syringe temperature gradient were compared using ANOVA. A P-value of less than 0.05 was considered statistically significant.Results: Syringe warming differed significantly between the four syringe brands for both the battery-operated and main power-operated mode (ANOVA, P< 0.001 for both modes). Individual differences between syringe surface and ambient temperature ranged from 0.3 to 1.9 degrees C for battery operation and from 0.5 to 11.2 degrees C during main-power operation.Conclusion: Infusion solutions can be significantly warmed by syringe pumps. This has potential impact on bacterial growth and the stability of drug solutions and blood products infused, as well as on the susceptibility to hydrostatic pressure changes within the infusion syringe. [ABSTRACT FROM AUTHOR]

Investigates the extent of start-up delays in fluid delivery for different syringe pumps after initially placing the infusion syringe in the syringe pump. Factors attributed to the delay in continuous fluid delivery; Clinical importance of findings; Strategies employed by nurses and physicians to avoid decline in plasma concentrations of most inotropic drugs towards zero during maintenance critical care.

Background: Blood sampling from arterial lines is a frequent event in anesthesia and critical care. To avoid clot formation, both the stopcock outlet and the cannula must be flushed after sampling. We investigated in a bench experiment whether fluid flow through the cannula is affected by the sequence of flushing procedures.Methods: Continuity of fluid delivery from a vascular cannula was gravimetrically determined using two different flushing techniques with either a syringe pump flush system or a bag flush system. The procedures comprised first flushing the stopcock towards the cannula and then towards the stopcock sampling outlet or the reverse order. Experiments were repeated in triplicate and two sets for each flushing system at hydrostatic pressures of 37 mm Hg and 74 mm Hg.Results: The main finding of the study was that flushing the stopcock towards the outlet after flushing the cannula resulted in considerable retrograde aspiration volumes and zero flow times, in particular in combination with syringe pump flush systems. At a hydrostatic pressure of 74 mm Hg, the observed zero flow time at the cannula tip amounted to (mean+/-SD) 0.1+/-0.01 min with the bag flush system and 7.7+/-0.5 min with the syringe pump flush system. The related retrograde aspiration volumes were 2.2+/-0.7 microl with the bag system and 30.0+/-2.0 microl with the syringe pump system. No backflow was recorded when the stopcock was first flushed to ambient pressure and then afterwards towards the cannula.Conclusion: Opening a flush system to ambient pressure affects the continuity of fluid delivery, particularly when using syringe pump flush systems. After blood sampling, the stopcock outlet should be flushed first followed by cannula flushing. [ABSTRACT FROM AUTHOR]

Fluid delivery from four types of commercially available 50-ml syringes was measured using an electronic balance at an infusion rate of 1 ml.h-1. Retrograde aspiration volume and zero-drug delivery time were recorded after lowering the syringe pump by 50 cm. Syringe compliance was calculated from the volume of bolus released after occlusion at 100 mmHg. Zero-drug delivery times differed significantly between syringes, ranging from [mean (SD)] 3.26 (0.40) min to 6.38 (0.56) min (F = 55.5, d.f. = 3/20, p < 0.0001). Syringe compliance correlated well with aspiration volume (Pearson r2 = 0.92, p < 0.001) and zero-drug delivery time (r2 = 0.90, p < 0.001). Syringe design affected the internal syringe compliance. All syringes were associated with potentially relevant zero-drug delivery times after moderate vertical displacement. To minimise this risk, vertical displacement of syringe pumps delivering highly vasoactive drugs should be avoided. [ABSTRACT FROM AUTHOR]

Infusion devices for continuous and precise drug administration are indispensable tools in anaesthesia and critical care medicine. Problems such as start-up delays, non-continuous flow and susceptibility to hydrostatic pressure changes at low infusion rates resulting in accidental bolus release or prolonged flow interruption are inherent to current infusion technology. In order to improve precise drug delivery, an innovative technical concept has been realised in a novel microvolumetric infusion pump (MVIP) device. The MVIP principle includes repeated filling and emptying of a non-compliant microsyringe without the use of valves. The performance of the MVIP prototype has been evaluated and compared with standard syringe infusion pump assemblies. The novel MVIP concept has thereby proven to eliminate most problems during infusion start-up, steady state flow and vertical pump displacement, and has the potential of revolutionising infusion technology and setting a new dimension in patient safety.