Hypercat - hypercube of AGN tori

AbstarctWe introduce Hypercat, a large set of 2-d AGN torus images computed with the state-of-the-art clumpy radiative transfer code Clumpy. The images are provided as a 9-dimensional hypercube, in addition to a smaller hypercube of corresponding projected dust distribution maps. Hypercat also comprises a software suite for easy use of the hypercubes, quantification of image morphology, and simulation of synthetic observations with single-dish telescopes, interferometers, and Integral Field Units. We apply Hypercat to NGC 1068 and find that it can be spatially resolved in Near- and Mid-IR, for the first time with single-dish apertures, on the upcoming generation of 25–40m class telescopes. We also find that clumpy AGN torus models within a range of the parameter space can explain on scales of several parsec the recently reported polar elongation of MIR emission in several sources, while not upending basic assumptions about AGN unification.

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SDSS-IV MaNGA: Observational Evidence of a Density-bounded Region in a Lyα Emitter

The Astrophysical Journal ◽

10.3847/1538-4357/ac33a5 ◽

2022 ◽

Vol 924 (2) ◽

pp. 47

Author(s):

Abhishek Paswan ◽

Kanak Saha ◽

Claus Leitherer ◽

Daniel Schaerer

Keyword(s):

Gas Phase ◽

Observational Evidence ◽

Moderate Correlation ◽

Spatially Resolved ◽

Lyman Continuum ◽

The Galaxy ◽

Field Unit ◽

Dust Distribution ◽

First Time ◽

Integral Field

Abstract Using integral field unit spectroscopy, we present here the spatially resolved morphologies of [S ii]λ6717,6731/Hα and [S ii]λ6717,6731/[O iii]λ5007 emission line ratios for the first time in a blueberry Lyα emitter (BBLAE) at z ∼ 0.047. Our derived morphologies show that the extreme starburst region of the BBLAE, populated by young (≤10 Myr), massive Wolf–Rayet stars, is [S ii] deficient, while the rest of the galaxy is [S ii] enhanced. We infer that the extreme starburst region is density-bounded (i.e., optically thin to ionizing photons), and the rest of the galaxy is ionization-bounded, indicating a Blister-type morphology. We find that the previously reported small escape fraction (10%) of Lyα photons is from our identified density-bounded H ii region of the BBLAE. This escape fraction is likely constrained by a porous dust distribution. We further report a moderate correlation between [S ii] deficiency and inferred Lyman continuum (LyC) escape fraction using a sample of confirmed LyC leakers studied in the literature, including the BBLAE studied here. The observed correlation also reveals its dependency on the stellar mass and gas-phase metallicity of the leaky galaxies. Finally, the future scope and implications of our work are discussed in detail.

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Global microbial necromass contribution to soil organic matter

10.21203/rs.3.rs-473688/v1 ◽

2021 ◽

Author(s):

Yuan Liu ◽

Jing Tian ◽

Nianpeng He ◽

Lisa Tiemann

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Soil Health ◽

Global Scale ◽

Data Sets ◽

Soil N ◽

Distribution Maps ◽

Spatially Resolved ◽

Biogeochemical Models ◽

First Time

Abstract Soil organic matter (SOM) plays an important role in mitigating climate change and sustaining soil health and food production 1,2. Mounting evidence suggests that microbial necromass is the main contributor to SOM 3; however, we lack quantification of microbial necromass at a global scale, especially in subsoils. Here, we generate, for the first time, global distribution maps of microbial necromass carbon (C) and nitrogen (N) and contributions to SOM in topsoil and subsoil. Globally, necromass concentrations varied widely across ecosystems and by latitude, contributing 19-60% to SOC and 41-92% to soil N stocks, with particularly large accumulations in boreal and tropical ecosystems. On average, fungal necromass contributions to SOM are 3x greater than bacterial, although this varied across ecosystems. Microbial necromass contributions to SOC are strongly associated with soil C:N ratios and pH; necromass contributions are greater in soils with narrow C:N ratios and higher pH. Microbial necromass is on average 23 and 77 times greater than living microbial biomass in topsoil and subsoil, respectively. These data highlight the importance of necromass contributions to SOM, especially soil N, and the need for spatially resolved necromass data sets that can be used in biogeochemical models to estimate SOM dynamics more accurately.

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Leveraging TSP Solver Complementarity through Machine Learning

Evolutionary Computation ◽

10.1162/evco_a_00215 ◽

2018 ◽

Vol 26 (4) ◽

pp. 597-620 ◽

Cited By ~ 12

Author(s):

Pascal Kerschke ◽

Lars Kotthoff ◽

Jakob Bossek ◽

Holger H. Hoos ◽

Heike Trautmann

Keyword(s):

Performance Improvement ◽

State Of The Art ◽

Large Set ◽

Depth Analysis ◽

Benchmark Instances ◽

Hard Problems ◽

Improved Performance ◽

First Time ◽

Travelling Salesperson Problem ◽

Insight Into

The Travelling Salesperson Problem (TSP) is one of the best-studied NP-hard problems. Over the years, many different solution approaches and solvers have been developed. For the first time, we directly compare five state-of-the-art inexact solvers—namely, LKH, EAX, restart variants of those, and MAOS—on a large set of well-known benchmark instances and demonstrate complementary performance, in that different instances may be solved most effectively by different algorithms. We leverage this complementarity to build an algorithm selector, which selects the best TSP solver on a per-instance basis and thus achieves significantly improved performance compared to the single best solver, representing an advance in the state of the art in solving the Euclidean TSP. Our in-depth analysis of the selectors provides insight into what drives this performance improvement.

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State-of-the-Art Char Production with a Focus on Bark Feedstocks: Processes, Design, and Applications

Processes ◽

10.3390/pr9010087 ◽

2021 ◽

Vol 9 (1) ◽

pp. 87

Author(s):

Ali Umut Şen ◽

Helena Pereira

Keyword(s):

State Of The Art ◽

Lignocellulosic Materials ◽

Heating Rates ◽

Production Methods ◽

Slow Pyrolysis ◽

Production Studies ◽

Lignocellulosic Feedstocks ◽

Thermochemical Method ◽

Superior Surface ◽

First Time

In recent years, there has been a surge of interest in char production from lignocellulosic biomass due to the fact of char’s interesting technological properties. Global char production in 2019 reached 53.6 million tons. Barks are among the most important and understudied lignocellulosic feedstocks that have a large potential for exploitation, given bark global production which is estimated to be as high as 400 million cubic meters per year. Chars can be produced from barks; however, in order to obtain the desired char yields and for simulation of the pyrolysis process, it is important to understand the differences between barks and woods and other lignocellulosic materials in addition to selecting a proper thermochemical method for bark-based char production. In this state-of-the-art review, after analyzing the main char production methods, barks were characterized for their chemical composition and compared with other important lignocellulosic materials. Following these steps, previous bark-based char production studies were analyzed, and different barks and process types were evaluated for the first time to guide future char production process designs based on bark feedstock. The dry and wet pyrolysis and gasification results of barks revealed that application of different particle sizes, heating rates, and solid residence times resulted in highly variable char yields between the temperature range of 220 °C and 600 °C. Bark-based char production should be primarily performed via a slow pyrolysis route, considering the superior surface properties of slow pyrolysis chars.

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UV Inscription and Pressure Induced Long-Period Gratings through 3D Printed Amplitude Masks

Sensors ◽

10.3390/s21061977 ◽

2021 ◽

Vol 21 (6) ◽

pp. 1977

Author(s):

Ricardo Oliveira ◽

Liliana M. Sousa ◽

Ana M. Rocha ◽

Rogério Nogueira ◽

Lúcia Bilro

Keyword(s):

State Of The Art ◽

Low Cost ◽

Resonance Wavelength ◽

Complex Structures ◽

Pressing Method ◽

Long Period ◽

Long Period Gratings ◽

3D Printed ◽

Mechanical Pressing ◽

First Time

In this work, we demonstrate for the first time the capability to inscribe long-period gratings (LPGs) with UV radiation using simple and low cost amplitude masks fabricated with a consumer grade 3D printer. The spectrum obtained for a grating with 690 µm period and 38 mm length presented good quality, showing sharp resonances (i.e., 3 dB bandwidth < 3 nm), low out-of-band loss (~0.2 dB), and dip losses up to 18 dB. Furthermore, the capability to select the resonance wavelength has been demonstrated using different amplitude mask periods. The customization of the masks makes it possible to fabricate gratings with complex structures. Additionally, the simplicity in 3D printing an amplitude mask solves the problem of the lack of amplitude masks on the market and avoids the use of high resolution motorized stages, as is the case of the point-by-point technique. Finally, the 3D printed masks were also used to induce LPGs using the mechanical pressing method. Due to the better resolution of these masks compared to ones described on the state of the art, we were able to induce gratings with higher quality, such as low out-of-band loss (0.6 dB), reduced spectral ripples, and narrow bandwidths (~3 nm).

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Electro-Quasistatic Animal Body Communication for Untethered Rodent Biopotential Recording

Scientific Reports ◽

10.1038/s41598-021-81108-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Shreeya Sriram ◽

Shitij Avlani ◽

Matthew P. Ward ◽

Shreyas Sen

Keyword(s):

Lower Energy ◽

Sensor Node ◽

State Of The Art ◽

The Body ◽

Animal Body ◽

Current State ◽

Communication Modalities ◽

First Time ◽

Biopotential Recording

AbstractContinuous multi-channel monitoring of biopotential signals is vital in understanding the body as a whole, facilitating accurate models and predictions in neural research. The current state of the art in wireless technologies for untethered biopotential recordings rely on radiative electromagnetic (EM) fields. In such transmissions, only a small fraction of this energy is received since the EM fields are widely radiated resulting in lossy inefficient systems. Using the body as a communication medium (similar to a ’wire’) allows for the containment of the energy within the body, yielding order(s) of magnitude lower energy than radiative EM communication. In this work, we introduce Animal Body Communication (ABC), which utilizes the concept of using the body as a medium into the domain of untethered animal biopotential recording. This work, for the first time, develops the theory and models for animal body communication circuitry and channel loss. Using this theoretical model, a sub-inch$$^3$$ 3 [1″ × 1″ × 0.4″], custom-designed sensor node is built using off the shelf components which is capable of sensing and transmitting biopotential signals, through the body of the rat at significantly lower powers compared to traditional wireless transmissions. In-vivo experimental analysis proves that ABC successfully transmits acquired electrocardiogram (EKG) signals through the body with correlation $$>99\%$$ > 99 % when compared to traditional wireless communication modalities, with a 50$$\times$$ × reduction in power consumption.

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Thermoelectric Sensor Coupled Yagi–Uda Nanoantenna for Infrared Detection

Electronics ◽

10.3390/electronics10050527 ◽

2021 ◽

Vol 10 (5) ◽

pp. 527

Author(s):

Waleed Tariq Sethi ◽

Olivier De Sagazan ◽

Mohamed Himdi ◽

Hamsakutty Vettikalladi ◽

Saleh A. Alshebeili

Keyword(s):

State Of The Art ◽

Infrared Detection ◽

Single Element ◽

Center Wavelength ◽

Resonance Response ◽

Thermal Measurements ◽

Radiation Induced ◽

Thermoelectric Sensor ◽

Junction Array ◽

First Time

We present an experimental demonstration of a thermoelectric sensor coupled with a nanoantenna as an alternative option for detecting infrared energy. Two nanoantenna design (single element and an array) variations based on Yagi-Uda technology and one separate nano-thermoelectric junction array were fabricated and tested. The nanoantennas were tuned to operate and respond at a center wavelength of 1550 nm (193.5 THz) optical C-band window, but they also exhibited a resonance response when excited by lasers of various wavelengths (650 nm and 940 nm). The radiation-induced electric currents in the nanoantennas, coupled with a nano-thermoelectric sensor, produced a potential difference as per the Seebeck effect. With respect to the uniform thermal measurements of the reference nanoantenna, the experiments confirmed the detection properties of the proposed nanoantennas; the single element detected a peak percentage voltage hike of 28%, whereas the array detected a peak percentage voltage hike of 80% at the center wavelength. Compared to state-of-the-art thermoelectric designs, this was the first time that such peak percentage voltages were experimentally reported following a planar design based on the Seebeck principle.

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A Synopsis of Orthotrichum s. lato (Bryophyta, Orthotrichaceae) in China, with Distribution Maps and a Key to Determination

Plants ◽

10.3390/plants10030499 ◽

2021 ◽

Vol 10 (3) ◽

pp. 499

Author(s):

Vítězslav Plášek ◽

Zuzana Komínková ◽

Ryszard Ochyra ◽

Lucie Fialová ◽

Shuiliang Guo ◽

...

Keyword(s):

Single Species ◽

Herbarium Specimens ◽

Distribution Maps ◽

First Time

A total of 46 species and two varieties of the traditionally interpreted genus Orthotrichum are currently known to occur in China. They represent five genera, including Orthotrichum (29 species), Lewinskya (14 species and two varieties), and Nyholmiella and Leratia that are represented by a single species each. The fifth genus Florschuetziella, also consisting of only one species, F. scaberrima, is an entirely neglected representative of the China’s moss flora. A list of all accepted taxa is presented and for each taxon all literature records and herbarium specimens are enumerated for provinces in which they have been recorded, and their distribution is mapped. A key to determination of Chinese orthotrichalean mosses is presented. A chronological list of 63 species and varieties and two designations, O. catagonioides and O. microsporum which have never been validly published, reported from China in the years 1892–2020 is presented. Four species, Orthotrichum brasii, O. hooglandii, O. elegans and O. gymnostomum are excluded from the bryoflora of China and Lewinskya affinis var. bohemica and Orthotrichum schimperi are recorded for the first time from this country. Phytogeography of the Chinese taxa of the orthotrichalean mosses is considered and they are grouped into eight phytogeographical elements and five sub-elements.

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On the path toward a universal outflow mechanism in light of NGC 4151 and NGC 1068

Proceedings of the International Astronomical Union ◽

10.1017/s174392132000201x ◽

2020 ◽

Vol 15 (S359) ◽

pp. 283-284

Author(s):

D. May ◽

J. E. Steiner ◽

R. B. Menezes

Keyword(s):

Near Infrared ◽

Feedback Mechanism ◽

Data Cube ◽

Low Velocity ◽

Ionized Gas ◽

Ngc 4151 ◽

Molecular Outflow ◽

Ngc 1068 ◽

Field Unit ◽

First Time

AbstractWe use near-infrared Integral Field Unit (IFU) data to analyze the galaxies NGC 4151 and NGC 1068, which have very different Eddington ratios - ˜50 times lower for NGC 4151. Together with a detailed data cube treatment methodology, we reveal remarkable similarities between both AGN, such as the detection of the walls of an “hourglass” structure for the low-velocity [Fe ii] emission with the high-velocity emission within this hourglass; a molecular outflow - detected for the first time in NGC 4151; and the fragmentation of an expanding molecular bubble into bullets of ionized gas. Such observations suggest that NGC 4151 could represent a less powerful and more compact version of the outflow seen in NGC 1068, suggesting a universal feedback mechanism acting in quite different AGN.

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Domain Adaptation Using a Three-Way Decision Improves the Identification of Autism Patients from Multisite fMRI Data

Brain Sciences ◽

10.3390/brainsci11050603 ◽

2021 ◽

Vol 11 (5) ◽

pp. 603

Author(s):

Chunlei Shi ◽

Xianwei Xin ◽

Jiacai Zhang

Keyword(s):

Machine Learning ◽

Domain Adaptation ◽

Recognition Accuracy ◽

State Of The Art ◽

Autism Spectrum ◽

Fmri Data ◽

Target Domain ◽

Sample Distribution ◽

Machine Learning Methods ◽

First Time

Machine learning methods are widely used in autism spectrum disorder (ASD) diagnosis. Due to the lack of labelled ASD data, multisite data are often pooled together to expand the sample size. However, the heterogeneity that exists among different sites leads to the degeneration of machine learning models. Herein, the three-way decision theory was introduced into unsupervised domain adaptation in the first time, and applied to optimize the pseudolabel of the target domain/site from functional magnetic resonance imaging (fMRI) features related to ASD patients. The experimental results using multisite fMRI data show that our method not only narrows the gap of the sample distribution among domains but is also superior to the state-of-the-art domain adaptation methods in ASD recognition. Specifically, the ASD recognition accuracy of the proposed method is improved on all the six tasks, by 70.80%, 75.41%, 69.91%, 72.13%, 71.01% and 68.85%, respectively, compared with the existing methods.

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