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.
Ovarian cancer is a heterogeneous disease that encompasses a number of different cellular subtypes, the most common of which is high-grade serous ovarian cancer (HGSOC). Still today, ovarian cancer ...is primarily treated with chemotherapy and surgery. Recent advances in the hereditary understanding of this disease have shown a significant role for the BRCA gene. While only a minority of patients with HGSOC will have a germline BRCA mutation, many others may have tumor genetic aberrations within BRCA or other homologous recombination proteins. Genetic screening for these BRCA mutations has allowed improved preventative measures and therapeutic development. This review focuses on the understanding of BRCA mutations and their relationship with ovarian cancer development, as well as future therapeutic targets.
We present a unitary correlation operator that explicitly induces into shell model type many-body states short ranged two-body correlations caused by the strong repulsive core and the pronounced ...tensor part of the nucleon–nucleon interaction. Alternatively an effective Hamiltonian can be defined by applying this unitary correlator to the realistic nucleon–nucleon interaction. The momentum space representation shows that realistic interactions which differ in their short range behaviour are mapped on the same correlated Hamiltonian, indicating a successful provision for the correlations at high momenta. Calculations for
4He using the one- and two-body part of the correlated Hamiltonian compare favorably with exact many-body methods. For heavier nuclei like
16O and
40Ca where exact many-body calculations are not possible we compare our results with other approximations. The correlated single-particle momentum distributions describe the occupation of states above the Fermi momentum. The Unitary Correlation Operator Method (UCOM) can be used in mean-field and shell model configuration spaces that are not able to describe these repulsive and tensor correlations explicitly.
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.
Small RNA pathways play key and diverse regulatory roles in C. elegans, but our understanding of their conservation and contributions in other nematodes is limited. We analyzed small RNA pathways in ...the divergent parasitic nematode Ascaris. Ascaris has ten Argonautes with five worm-specific Argonautes (WAGOs) that associate with secondary 5'-triphosphate 22-24G-RNAs. These small RNAs target repetitive sequences or mature mRNAs and are similar to the C. elegans mutator, nuclear, and CSR-1 small RNA pathways. Even in the absence of a piRNA pathway, Ascaris CSR-1 may still function to "license" as well as fine-tune or repress gene expression. Ascaris ALG-4 and its associated 26G-RNAs target and likely repress specific mRNAs during testis meiosis. Ascaris WAGO small RNAs demonstrate target plasticity changing their targets between repeats and mRNAs during development. We provide a unique and comprehensive view of mRNA and small RNA expression throughout spermatogenesis. Overall, our study illustrates the conservation, divergence, dynamics, and flexibility of small RNA pathways in nematodes.
The pair decay width of the first excited 0+ state in 12C (the Hoyle state) is deduced from a novel analysis of the world data on inelastic electron scattering covering a wide momentum transfer ...range, thereby resolving previous discrepancies. The extracted value Γπ=(62.3±2.0) μeV is independently confirmed by new data at low momentum transfers measured at the S-DALINAC and reduces the uncertainty of the literature values by more than a factor of 3. A precise knowledge of Γπ is mandatory for quantitative studies of some key issues in the modeling of supernovae and of asymptotic giant branch stars, the most likely site of the slow-neutron nucleosynthesis process.
Report mid-term outcomes of thoracic endovascular aneurysm repair (TEVAR) with chimney and periscope grafts (CPG) in supra-aortic branches (SAB).
Retrospective analysis, from October 2009 to May ...2014, of patients with aneurysms requiring TEVAR with zone 0/1/2 proximal landing in association with at least one CPG in the SAB. All patients were considered at high risk for conventional surgery. Peri-operative mortality and morbidity, retrograde type A dissection, maximum aortic transverse diameter (TD) and its post-operative evolution, endoleak, survival, freedom from cardiovascular re-interventions, and CPG freedom from occlusion during the follow-up were analysed.
Forty-one patients (28.05% EuroScore II) with thoraco-abdominal aortic aneurysm (17%), arch aneurysm (39%), descending aneurysm (34%), and aneurysm extending from the arch to the visceral aorta (10%) were included. Fifteen (37%) patients were treated non-electively. Fifty-nine SABs were treated with the CPG technique: one, two, three, and four CPG were employed in 71%, 19%, 5%, and 5% of patients, respectively. The proximal landing was in zone 0 in 49% of patients, zone 1 in 17%, and zone 2 in 34%. Technical success was 95%. Peri-operative complications and neurological events were registered in six (14.6%) patients and there were 5 deaths (12%). At a median follow-up of 21.2 (mean 22, SD 18; range 0–65) months, type I/III endoleaks were registered in three (7%) cases and re-intervention in six (15%) patients. A significant aneurysm sac shrinkage (p<.001) was reported at mean follow-up and no significant aneurysm sac increase (>5 mm). The estimated 2 year survival, freedom from re-intervention, freedom from endoleak, and freedom from branch occlusion were 75%, 77%, 86%, and 96%, respectively.
The chimney and periscope grafts technique was shown to be safe in aortic aneurysm disease involving the supra aortic branches, even in an emergency setting using off the shelf devices. Mid-term follow-up results in this high risk population are good, but longer follow-up is mandatory before this technique is used in intermediate-risk patients.
Pluripotency is a unique state in which cells can self-renew indefinitely but also retain the ability to differentiate into other cell types upon receipt of extracellular cues. Although it is clear ...that stem cells have a distinct transcriptional program, little is known about how alterations in post-transcriptional mechanisms, such as mRNA turnover, contribute to the achievement and maintenance of pluripotency. Here we have assessed the rates of decay for the majority of mRNAs expressed in induced pluripotent stem (iPS) cells and the fully differentiated human foreskin fibroblasts (HFFs) they were derived from. Comparison of decay rates in the two cell types led to the discovery of three independent regulatory mechanisms that allow coordinated turnover of specific groups of mRNAs. One mechanism results in increased stability of many histone mRNAs in iPS cells. A second pathway stabilizes a large set of zinc finger protein mRNAs, potentially through reduced levels of miRNAs that target them. Finally, a group of transcripts bearing 3' UTR C-rich sequence elements, many of which encode transcription factors, are significantly less stable in iPS cells. Intriguingly, two poly(C)-binding proteins that recognize this type of element are reciprocally expressed in iPS and HFF cells. Overall, our results highlight the importance of post-transcriptional control in pluripotent cells and identify miRNAs and RNA-binding proteins whose activity may coordinately control expression of a wide range of genes in iPS cells.
Mycophenolate mofetil (MMF) use may be associated with progressive multifocal leukoencephalopathy (PML). We conducted a retrospective cohort study of 32,757 renal transplant recipients using the ...United States Renal Data System kidney transplant files for the incidence, prognosis, and clinical features associated with PML occurring after kidney transplant. Subjects were transplanted from January 1, 2000 to July 31, 2004 and followed through December 31, 2004. The incidence density of PML in MMF users was 14.4 cases/100,000 person-years at risk versus 0 for non-MMF users (P=0.11) by log rank test. Factors significantly associated with PML were BK virus infection (22.2% vs. 1.1%), pretransplant transfusion (75% vs. 34%), panel reactive antibody more than 20% (56% vs. 14%), and use of antirejection medications in the first year (33% vs. 9.2%), all P less than 0.05. PML is rare in the renal transplant population. There was no significant association between PML and MMF, but MMF use in this cohort is too high to accurately assess an association.
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