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Parallelization of frequency domain quantum gates:manipulation and distribution of frequency-entangled photon pairs generated by a 21 GHz silicon microresonator

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Advanced Photonics 2024年第3期6卷 60-69页

作者： Antoine Henry Dario A.Fioretto lorenzo m.Procopio Stéphane monfray Frédéric Boeuf Laurent Vivien Eric Cassan Carlos Alonzo-Ramos Kamel Bencheikh Isabelle Zaquine Nadia Belabas Institut Polytechnique de Paris LTCI Université Paris-Saclay CNRS Centre for Nanosciences and Nanotechnology Weizmann Institute of Science STmicroelectronics SAS

Harnessing the frequency dimension in integrated photonics offers key advantages in terms of scalability, noise resilience, parallelization, and compatibility with telecom multiplexing *** ring resonators have been used to generate frequency-entangled states through spontaneous four-wave mixing. However, state-of-the-art integrated resonators are limited by trade-offs among size,spectral separation, and efficient photon pair generation. We have developed silicon ring resonators with a footprint below 0.05 mm2providing more than 70 frequency channels separated by 21 GHz. We exploit the narrow frequency separation to parallelize and independently control 34 single qubit-gates with a single set of three off-the-shelf electro-optic devices. We fully characterize 17 frequency-bin maximally entangled qubit pairs by performing quantum state tomography. We demonstrate for the first time, we believe, a fully connected five-user quantum network in the frequency domain. These results are a step towards a generation of quantum circuits implemented with scalable silicon photonics technology, for applications in quantum computing and secure communications.

关键词： frequency domain integrated photonics quantum gates quantum networks

microstructure segmentation with deep learning encoders pre-trained on a large microscopy dataset

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npj Computational materials 2022年第1期8卷 1905-1916页

作者： Joshua Stuckner Bryan Harder Timothy m.smith materials and Structures Division NASA Glenn Research Center21000 Brookpark RdClevelandOH44135USA

This study examined the improvement of microscopy segmentation intersection over union accuracy by transfer learning from a large dataset of microscopy images called *** neural network encoder architectures were trained on over 100,000 labeled microscopy images from 54 material *** pre-trained encoders were then embedded into multiple segmentation architectures including UNet and DeepLabV3+to evaluate segmentation performance on created benchmark microscopy *** to ImageNet pre-training,models pre-trained on microNet generalized better to out-of-distribution micrographs taken under different imaging and sample conditions and were more accurate with less training *** training with only a single Ni-superalloy image,pre-training on microNet produced a 72.2%reduction in relative intersection over union *** results suggest that transfer learning from large in-domain datasets generate models with learned feature representations that are more useful for downstream tasks and will likely improve any microscopy image analysis technique that can leverage pre-trained encoders.

关键词： union intersection image

Strigolactones redefine plant hormones

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Science China(Life Sciences) 2016年第10期59卷 1083-1085页

作者： Lu Wang Steven m.smith School of Biological Sciences University of Tasmania Institute of Genetics and Developmental Biology Chinese Academy of sciences

A commonly accepted view of plant growth hormones is that their interaction with the cognate receptor protein is reversible, so that each hormone molecule can potentially interact multiple times with a receptor and so either amplify the hormone signal or maintain it over an extended period of time. The signal can be ＇cancelled＇ by degrading the hormone. Strigolactones present us with a potentially new paradigm. The receptor is a serine hydrolase-type protein which attacks the strigolactone resulting in covalent modi- fication of the receptor, while at the same time destroying the hormone. Strigolactone is apparently a one-use ＇dispos- able＇ hormone.

关键词：植物激素受体蛋白定义植物生长激素相互作用激素信号酸水解

History and evaluation of national-scale geochemical data sets for the United States

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Geoscience Frontiers 2013年第2期4卷 167-183页

作者： David B.smith Steven m.smith John D.Horton U.S.Geological Survey.Denver Federal Center MS 973.DenverCO 80225USA

Six national-scale,or near national-scale,geochemical data sets for soils or stream sediments exist for the United *** earliest of these,here termed the ＇Shacklette＇ data set,was generated by a U.S. Geological Survey（USGS） project conducted from 1961 to *** project used soil collected from a depth of about 20 cm as the sampling medium at 1323 sites throughout the conterminous *** National Uranium Resource Evaluation Hydrogeochemical and Stream Sediment Reconnaissance（NUREHSSR） Program of the *** of Energy was conducted from 1975 to 1984 and collected either stream sediments,lake sediments,or soils at more than 378,000 sites in both the conterminous *** *** sampled area represented about 65%of the *** Natural Resources Conservation Service（NRCS）,from 1978 to 1982,collected samples from multiple soil horizons at sites within the major crop-growing regions of the conterminous *** data set contains analyses of more than 3000 *** National Geochemical Survey,a USGS project conducted from 1997 to 2009,used a subset of the NURE-HSSR archival samples as its starting point and then collected primarily stream sediments, with occasional soils,in the parts of the *** covered by the NURE-HSSR *** data set contains chemical analyses for more than 70,000 *** USGS,in collaboration with the mexican Geological Survey and the Geological Survey of Canada,initiated soil sampling for the North American Soil Geochemical Landscapes Project in *** of three horizons or depths at more than 4800 sites in the *** completed in 2010,and chemical analyses are currently *** NRCS initiated a project in the 1990s to analyze the various soil horizons from selected pedons throughout the *** data set currently contains data from more than 1400 *** paper（1） discusses each data set in terms of its purpose,sample collection protocols,and analytical methods;and（2） evaluates each data set in terms

关键词： Geochemical mapping National-scale geochemical data Geochemical baselines United States

Dewatering of Scenedesmus obliquus Cultivation Substrate with microfiltration:Potential and Challenges for Water Reuse and Effective Harvesting

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Engineering 2024年第7期38卷 155-163页

作者： marco malaguti lorenzo Craveri Francesco Ricceri Vincenzo Riggio mariachiara Zanetti Alberto Tiraferri Department of Environment Land and Infrastructure EngineeringPolitecnico di TorinoTorino 10129Italy Clean Water Center Politecnico di TorinoTorino 10129Italy

In the microalgae harvesting process,which includes a step for dewatering the algal suspension,directly reusing extracted water in situ would decrease the freshwater footprint of cultivation *** various algae harvesting techniques,membrane-based filtration has shown numerous *** study evaluated the reuse of permeate streams derived from Scenedesmus obliquus(***)biomass filtration under bench-scale and pilot-scale *** particular,this study identified a series of challenges and mechanisms that influence the water reuse potential and the robustness of the membrane harvesting *** a preliminary phase of this investigation,the health status of the initial biomass was found to have important implications for the harvesting performance and quality of the permeate stream to be reused;healthy biomass ensured better dewatering performance(i.e.,higher water fluxes)and higher quality of the permeate water streams.A series of bench-scale filtration experiments with different combinations of cross-flow velocity and pressure values were performed to identify the operative conditions that would maximize water *** selected conditions,2.4 m·s^(-1)and 1.4 bar(1 bar=105 Pa),respectively,were then applied to drive pilot-scale microfiltration tests to reuse the collected permeate as a new cultivation medium for *** growth in a pilot-scale *** investigation revealed key differences between the behavior of the membrane systems at the two scales(bench and pilot).It indicated the potential for beneficial reuse of the permeate stream as the pilot-scale experiments ensured high harvesting performance and growth rates of biomass in permeate water that were highly similar to those recorded in the ideal cultivation ***,different nutrient reintegration protocols were investigated,revealing that both macro-and micro-nutrient levels are critical for the success of the reuse approach.

关键词： Scenedesmus obliquus microfiltration Permeate reuse Harvesting microalgae Pilot-scale

Breeding high-yield superior quality hybrid super rice by rational design

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National Science Review 2016年第3期3卷 283-294页

作者： Qian Qian Longbiao Guo Steven m.smith Jiayang Li State Key Laboratory for Rice Biology China National Rice Research InstituteChinese Academy of Agricultural Sciences State Key Laboratory of Plant Genomics and National Center for Plant Gene Research(Beijing) Institute of Genetics and Developmental BiologyChinese Academy of Sciences Agricultural Genomics Institute at Shenzhen Chinese Academy of Agricultural Sciences School of Biological Sciences University of Tasmania

The challenge of meeting the increasing demand for worldwide rice production has driven a sustained quest for advances in rice breeding for yield. Two breakthroughs that led to quantum leaps in productivity last century were the introduction of semidwarf varieties and of hybrid rice. Subsequent gains in yield have been incremental. The next major leap in rice breeding is now upon us through the application of rational design to create defined ideotypes. The exploitation of wide-cross compatibility and intersubspecific heterosis,combined with rapid genome sequencing and the molecular identification of genes for major yield and quality traits have now unlocked the potential for rational design.

关键词： Oryza sativa L super rice hybrids molecular breeding grain yield grain quality

Reactive astrocyte scar and axon regeneration:suppressor or facilitator?

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Neural Regeneration Research 2016年第7期11卷 1050-1051页

作者： Yosuke Ohtake George m.smith Shuxin Li Shriners Hospitals Pediatric Research Center Department of Anatomy and Cell BiologyDepartment of NeuroscienceLewis Katz School of Medicine at Temple University

Several major factors are known to contribute to CNS axon regenerative failure after injury, including reduced intrinsic growth capacity of developed neurons and extrinsic factors mediating axon outgrowth. For the latter, a non-permissive environment around the lesion and the lack of sufficient neurotrophic support within the adult CNS play important roles （Silver et al., 2015）. In addition to generation of various inhibitory substrates by oligodendrocytes, fibrotic tissues, inflammatory cells and other cell types, reactive astrocytes surrounding lesions are thought to highly suppress regeneration of injured CNS axons （Silver and miller, 2004; Ohtake and Li, 2014）. A great number of studies suggest that reactive astrocytic scars form one of the major barriers preventing axon regeneration after CNS iniuries, including spinal cord injury （SCI）. However, reactive astrocytes were reported to provide a beneficial role by reducing infiltrating immunoreactive cells into adjacent domains, protecting bordering neural tissue from damage and generating numerous supportive extracellular matrix （ECm） components to promote cell survival and growth （Bush et al., 1999）. Previ- ous data showed that ablation of reactive astrocytes increased inflammation and secondary tissue damage, prevented blood- brain barrier formation and increased local neurite growth. Interestingly, a recent study by Anderson et al （2016） provides evidence that reactive astrocytes around the lesioned spinal cord support axon regeneration after SCI, rather than block regrowth （Anderson et al., 2016）.

关键词： astrocyte regeneration suppressor neurotrophic extrinsic latter intrinsic glial injured sensory

Automated SNP Genotype Clustering Algorithm to Improve Data Completeness in High-Throughput SNP Genotyping Datasets from Custom Arrays

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Genomics, Proteomics & Bioinformatics 2007年第3期5卷 256-259页

作者： Edward m.smith Jack Littrell michael Olivier Human and molecular Genetics Center Medical College of WisconsinMilwaukeeWI 53226USA.

High-throughput SNP genotyping platforms use automated genotype calling algorithms to assign genotypes. While these algorithms work efficiently for individual platforms, they are not compatible with other platforms, and have individual biases that result in missed genotype calls. Here we present data on the use of a second complementary SNP genotype clustering algorithm. The algorithm was originally designed for individual fluorescent SNP genotyping assays, and has been optimized to permit the clustering of large datasets generated from custom-designed Affymetrix SNP panels. In an analysis of data from a 3K array genotyped on 1,560 samples, the additional analysis increased the overall number of genotypes by over 45,000, significantly improving the completeness of the experimental data. This analysis suggests that the use of multiple genotype calling algorithms may be advisable in high-throughput SNP genotyping experiments. The software is written in Perl and is available from the corresponding author.

关键词： clustering SNP genotyping algorithm

A Hybrid model Evaluation Based on PCA Regression Schemes Applied to Seasonal Precipitation Forecast

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Atmospheric and Climate Sciences 2024年第3期14卷 328-353页

作者： Pedro m. González-Jardines Aleida Rosquete-Estévez maibys Sierra-lorenzo Arnoldo Bezanilla-morlot Center for Atmospheric Physics Institute of Meteorology Havana Cuba

Possible changes in the structure and seasonal variability of the subtropical ridge may lead to changes in the rainfall’s variability modes over Caribbean region. This generates additional difficulties around water resource planning, therefore, obtaining seasonal prediction models that allow these variations to be characterized in detail, it’s a concern, specially for island states. This research proposes the construction of statistical-dynamic models based on PCA regression methods. It is used as predictand the monthly precipitation accumulated, while the predictors (6) are extracted from the ECmWF-SEAS5 ensemble mean forecasts with a lag of one month with respect to the target month. In the construction of the models, two sequential training schemes are evaluated, obtaining that only the shorter preserves the seasonal characteristics of the predictand. The evaluation metrics used, where cell-point and dichotomous methodologies are combined, suggest that the predictors related to sea surface temperatures do not adequately represent the seasonal variability of the predictand, however, others such as the temperature at 850 hPa and the Outgoing Longwave Radiation are represented with a good approximation regardless of the model chosen. In this sense, the models built with the nearest neighbor methodology were the most efficient. Using the individual models with the best results, an ensemble is built that allows improving the individual skill of the models selected as members by correcting the underestimation of precipitation in the dynamic model during the wet season, although problems of overestimation persist for thresholds lower than 50 mm.

关键词： Seasonal Forecast Principal Component Regression Statistical-Dynamic models