105 research outputs found

    Neural Fourier Filter Bank

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    We present a novel method to provide efficient and highly detailed reconstructions. Inspired by wavelets, we learn a neural field that decompose the signal both spatially and frequency-wise. We follow the recent grid-based paradigm for spatial decomposition, but unlike existing work, encourage specific frequencies to be stored in each grid via Fourier features encodings. We then apply a multi-layer perceptron with sine activations, taking these Fourier encoded features in at appropriate layers so that higher-frequency components are accumulated on top of lower-frequency components sequentially, which we sum up to form the final output. We demonstrate that our method outperforms the state of the art regarding model compactness and convergence speed on multiple tasks: 2D image fitting, 3D shape reconstruction, and neural radiance fields. Our code is available at https://github.com/ubc-vision/NFFB

    Influence of D-Amino Acids in Beer on Formation of Uric Acid

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    Prekomjerna konzumacija piva može dovesti do povećanja koncentracije mokraćne kiseline u serumu, čime se povećava rizik nastanka uričnog artritisa (gihta), Å”to se prethodno dovodilo u vezu s velikim udjelom purina u pivu. Međutim, novija istraživanja pokazuju da konzumacija povrća bogatog purinima i grahorica ne povećava koncentraciju mokraćne kiseline, Å”to opovrgava tu tvrdnju. JoÅ” uvijek nije objaÅ”njeno zaÅ”to povećana konzumacija piva može povećati rizik nastanka gihta, pa su ispitani drugi uzročnici nakupljanja mokraćne kiseline u krvi. Pivo sadržava relativno velike koncentracije D-aminokiselina koje nastaju racemizacijom L-aminokiselina tijekom prerade hrane. Katalizom pomoću D-aminokiselinske oksidaze iz D-aminokiselina nastaje H2O2, čijom oksidacijom u prisutnosti Fe2+ nastaju hidroksilni radikali. Pritom dolazi do oÅ”tećenja DNA i nastanka purinskih baza u većoj količini, iz kojih djelovanjem različitih enzima nastaje mokraćna kiselina. Neki dodaci hrani, kao Å”to su vitamini i ioni joda, potiču nastanak mokraćne kiseline iz D-aminokiselina. D-aminokiseline u pivu imaju ključnu ulogu u povećanju koncentracije mokraćne kiseline. BioloÅ”ka uloga D-aminokiselina može objasniti pojavu gihta kod osoba koje učestalo konzumiraju pivo.Excessive intake of beer could increase serum uric acid levels, leading to high risk of gout, which was previously attributed to high purine content in beer. Recent reports that purine-rich vegetables and bean products do not cause higher uric acid levels do not support this theory. Why excessive intake of beer could increase a high risk of gout has been unclear. Other factors affecting the accumulation of uric acid in the blood have been explored. Beer contains relatively high levels of D-amino acids due to the racemization of l-amino acids induced by food processing. D-amino acid was catalyzed by D-amino acid oxidase to produce H2O2, which is further oxidized in the presence of Fe2+ to produce hydroxyl radicals, resulting in DNA damage and formation of a large amount of purine bases, which are oxidized to uric acid by a series of enzymes. Some food ingredients, such as vitamins and Iā€“, prompt D-amino acids to form uric acid. D-amino acids in beer are one of the key factors responsible for the increase in uric acid levels. The biological response of D-amino acids could explain gout occurrence in beer drinkers

    Nearly a decade-long repeatable seasonal diversity patterns of bacterioplankton communities in the eutrophic Lake Donghu (Wuhan, China).

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    Uncovering which environmental factors govern community diversity patterns and how ecological processes drive community turnover are key questions related to understand the community assembly. However, the ecological mechanisms regulating long-term variations of bacterioplankton communities in lake ecosystems remain poorly understood. Here we present nearly a decade-long study of bacterioplankton communities from the eutrophic Lake Donghu (Wuhan, China) using 16S rRNA gene amplicon sequencing with MiSeq platform. We found strong repeatable seasonal diversity patterns in terms of both common (detected in more than 50% samples) and dominant (relative abundance >1%) bacterial taxa turnover. Moreover, community composition tracked the seasonal temperature gradient, indicating that temperature is a key environmental factor controlling observed diversity patterns. Total phosphorus also contributed significantly to the seasonal shifts in bacterioplankton composition. However, any spatial pattern of bacterioplankton communities across the main lake areas within season was overwhelmed by their temporal variabilities. Phylogenetic analysis further indicated that 75%-82% of community turnover was governed by homogeneous selection due to consistent environmental conditions within seasons, suggesting that the microbial communities in Lake Donghu are mainly controlled by niche-based processes. Therefore, dominant niches available within seasons might be occupied by similar combinations of bacterial taxa with modest dispersal rates throughout different lake areas

    Benefits and risks of drug combination therapy for diabetes mellitus and its complications: a comprehensive review

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    Diabetes is a chronic metabolic disease, and its therapeutic goals focus on the effective management of blood glucose and various complications. Drug combination therapy has emerged as a comprehensive treatment approach for diabetes. An increasing number of studies have shown that, compared with monotherapy, combination therapy can bring significant clinical benefits while controlling blood glucose, weight, and blood pressure, as well as mitigating damage from certain complications and delaying their progression in diabetes, including both type 1 diabetes (T1D), type 2 diabetes (T2D) and related complications. This evidence provides strong support for the recommendation of combination therapy for diabetes and highlights the importance of combined treatment. In this review, we first provided a brief overview of the phenotype and pathogenesis of diabetes and discussed several conventional anti-diabetic medications currently used for the treatment of diabetes. We then reviewed several clinical trials and pre-clinical animal experiments on T1D, T2D, and their common complications to evaluate the efficacy and safety of different classes of drug combinations. In general, combination therapy plays a pivotal role in the management of diabetes. Integrating the effectiveness of multiple drugs enables more comprehensive and effective control of blood glucose without increasing the risk of hypoglycemia or other serious adverse events. However, specific treatment regimens should be tailored to individual patients and implemented under the guidance of healthcare professionals

    An Empirical Analysis of Farmers' Rabbit Breeds Purchase and Its Influencing Factors

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    In this paper, based on the survey data on farmers in 14 provinces and cities nationwide provided by China Rabbit Research System, we analyze the farmers' rabbit breeds selection, purchase channels and the demand for new varieties of rabbits as well as the problems in the course of rabbit usage. We make an empirical analysis of the factors influencing farmers' rabbit demand, and put forth the recommendations for farmers' rabbit breeds usage and to improve the promotion of new varieties of rabbits

    DSMC Simulation and Experimental Validation of Shock Interaction in Hypersonic Low Density Flow

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    Direct simulation Monte Carlo (DSMC) of shock interaction in hypersonic low density flow is developed. Three collision molecular models, including hard sphere (HS), variable hard sphere (VHS), and variable soft sphere (VSS), are employed in the DSMC study. The simulations of double-cone and Edneyā€™s type IV hypersonic shock interactions in low density flow are performed. Comparisons between DSMC and experimental data are conducted. Investigation of the double-cone hypersonic flow shows that three collision molecular models can predict the trend of pressure coefficient and the Stanton number. HS model shows the best agreement between DSMC simulation and experiment among three collision molecular models. Also, it shows that the agreement between DSMC and experiment is generally good for HS and VHS models in Edneyā€™s type IV shock interaction. However, it fails in the VSS model. Both double-cone and Edneyā€™s type IV shock interaction simulations show that the DSMC errors depend on the Knudsen number and the models employed for intermolecular interaction. With the increase in the Knudsen number, the DSMC error is decreased. The error is the smallest in HS compared with those in the VHS and VSS models. When the Knudsen number is in the level of 10āˆ’4, the DSMC errors, for pressure coefficient, the Stanton number, and the scale of interaction region, are controlled within 10%

    Rmcf2, a Xenotropic Provirus in the Asian Mouse Species Mus castaneus, Blocks Infection by Polytropic Mouse Gammaretroviruses

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    Cells from the Asian wild mouse species Mus castaneus are resistant to infection by the polytropic host range group of mouse gammaretroviruses. Two factors are responsible for this resistance: a defective XPR1 cell surface receptor for polytropic murine leukemia viruses (P-MLVs), and a resistance factor detectable only in interspecies hybrids between M. castaneus and mice with an XPR1 variant that permits infection by xenotropic MLVs (X-MLVs) as well as P-MLVs. This second novel virus resistance phenotype has been associated with expression of viral Env glycoprotein; Northern blotting with specific hybridization probes identified a spliced X-MLV env message unique to virus-resistant mice. These observations suggest that resistance is due to expression of one or more endogenous X-MLV envelope genes that interfere with infection by exogenous P-MLVs. M. castaneus contains multiple X-MLV proviruses, but serial backcrosses reduced this proviral content and permitted identification of a single proviral env sequence inherited with resistance. The resistance phenotype and the provirus were mapped to the same site on distal chromosome 18. The provirus was shown to be a full-length provirus highly homologous to previously described X-MLVs. Use of viral pseudotypes confirmed that this resistance gene, termed Rmcf2, prevents entry of P-MLVs. Rmcf2 resembles the virus resistance genes Fv4 and Rmcf in that it produces Env glycoprotein but fails to produce infectious virus; the proviruses associated with all three resistance genes have fatal defects. This type of provirus Env-mediated resistance represents an important defense mechanism in wild mouse populations exposed to endemic infections

    Machine performance assessment based on integrated signal redundancy and bootstrap technique

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    Prediction of machine performance based on current states and historical data has been a challenging issue in a predictive maintenance of machine performance assessment. Traditional methods mainly focused on developing prediction algorithms, rather than paying attention to the understanding of the data. This paper presents an innovative method to quantitatively evaluate the predictability of machinery performance assessment based on information redundancy and a statistical simulation technique. The predictability of a series of simulated signals including periodicity signal, simulated periodicity signal, chaos signal and random white noise signal were simulated for testing the correctness of the proposed method. In addition, practical vibration data were analyzed and a high-precision prediction was achieved by computing the redundancies of these sample sequences. Results indicate that evaluation tool can present a clear indication of machine performance predictability and therefore can guide the development and selection of prediction algorithms
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