Scattering matrix solution for an ideal star-junction multiplexer based on ladder-type filters

2020 ◽  
Vol 12 (10) ◽  
pp. 954-959 ◽  
Author(s):  
Patricia Silveira ◽  
Jordi Verdú ◽  
Pedro de Paco
Keyword(s):  
Optimization Procedure ◽  
Scattering Matrix ◽  
Matrix Solution ◽  
Full Wave ◽  
Direct Scattering ◽  
Starting Point ◽  
Lumped Elements ◽  
Good Starting Point ◽  
Numerical Computing ◽  
Suitable Environment

AbstractMultiplexer design is a challenging task due to the high number of variables involved, raising the difficulty as the numbers of filters increase. Numerical computing tools provide a suitable environment to evaluate topologies and technologies before starting the long journey to the device. A direct scattering matrix solution for a star-junction multiplexer, based on the circuit theory, is presented in this work. The resulting star-junction matrix is introduced in a matrix system with the scattering matrix of each filter to evaluate the overall multiplexer response. This approach allows the acquisition of main multiplexer parameters like transmission, reflection, and cross-isolation response in a compact way, achieving a good starting point for the further full-wave optimization procedure. Furthermore, an approach for the design of a star-junction multiplexer is tackled based on the reflection coefficient phase. A triplexer under this interpretation is presented and evaluated using lumped elements.

Dimensioning a recovery boiler furnace using mathematical optimization

TAPPI Journal ◽  
2015 ◽  
Vol 14 (2) ◽  
pp. 119-129 ◽  
Author(s):  
VILJAMI MAAKALA ◽  
PASI MIIKKULAINEN
Keyword(s):  
Radial Basis Function Network ◽  
High Capacity ◽  
Mathematical Optimization ◽  
Optimization Procedure ◽  
Optimization Method ◽  
Performance Criteria ◽  
Boiler Furnace ◽  
Starting Point ◽  
Recovery Boiler ◽  
Base Design

Capacities of the largest new recovery boilers are steadily rising, and there is every reason to expect this trend to continue. However, the furnace designs for these large boilers have not been optimized and, in general, are based on semiheuristic rules and experience with smaller boilers. We present a multiobjective optimization code suitable for diverse optimization tasks and use it to dimension a high-capacity recovery boiler furnace. The objective was to find the furnace dimensions (width, depth, and height) that optimize eight performance criteria while satisfying additional inequality constraints. The optimization procedure was carried out in a fully automatic manner by means of the code, which is based on a genetic algorithm optimization method and a radial basis function network surrogate model. The code was coupled with a recovery boiler furnace computational fluid dynamics model that was used to obtain performance information on the individual furnace designs considered. The optimization code found numerous furnace geometries that deliver better performance than the base design, which was taken as a starting point. We propose one of these as a better design for the high-capacity recovery boiler. In particular, the proposed design reduces the number of liquor particles landing on the walls by 37%, the average carbon monoxide (CO) content at nose level by 81%, and the regions of high CO content at nose level by 78% from the values obtained with the base design. We show that optimizing the furnace design can significantly improve recovery boiler performance.

scholarly journals Discovery and Optimization of Selective Inhibitors of Meprin α (Part I)

2021 ◽  
Vol 14 (3) ◽  
pp. 203 ◽  
Author(s):  
Shurong Hou ◽  
Juan Diez ◽  
Chao Wang ◽  
Christoph Becker-Pauly ◽  
Gregg B. Fields ◽  
...  
Keyword(s):  
Inhibitory Activity ◽  
De Novo ◽  
Selective Inhibitors ◽  
Preclinical Development ◽  
Starting Point ◽  
Good Starting Point ◽  
Parallel Screening ◽  
Low Cytotoxicity

Meprin α and β are zinc-dependent proteinases implicated in multiple diseases including cancers, fibrosis, and Alzheimer’s. However, until recently, only a few inhibitors of either meprin were reported and no inhibitors are in preclinical development. Moreover, inhibitors of other metzincins developed in previous years are not effective in inhibiting meprins suggesting the need for de novo discovery effort. To address the paucity of tractable meprin inhibitors we developed ultrahigh-throughput assays and conducted parallel screening of >650,000 compounds against each meprin. As a result of this effort, we identified five selective meprin α hits belonging to three different chemotypes (triazole-hydroxyacetamides, sulfonamide-hydroxypropanamides, and phenoxy-hydroxyacetamides). These hits demonstrated a nanomolar to micromolar inhibitory activity against meprin α with low cytotoxicity and >30-fold selectivity against meprin β and other related metzincincs. These selective inhibitors of meprin α provide a good starting point for further optimization.

scholarly journals Advances on the Implementation of Circular Economy Techniques in Rural Areas in Colombia under a Sustainable Development Framework

2021 ◽  
Vol 13 (7) ◽  
pp. 3816
Author(s):  
Javier Rodrigo-Ilarri ◽  
Camilo-A. Vargas-Terranova ◽  
María-Elena Rodrigo-Clavero ◽  
Paula-A. Bustos-Castro
Keyword(s):  
Sustainable Development ◽  
Waste Management ◽  
Circular Economy ◽  
Rural Areas ◽  
Development Framework ◽  
Starting Point ◽  
Management Plans ◽  
Good Starting Point ◽  
Depressed Regions ◽  
First Time

For the first time in the scientific literature, this research shows an analysis of the implementation of circular economy techniques under sustainable development framework in six municipalities with a depressed economy in Colombia. The analysis is based on solid waste data production at a local scale, the valuation of the waste for subsequent recycling, and the identification and quantification of the variables associated with the treatment and final disposal of waste, in accordance with the Colombian regulatory framework. Waste generation data are obtained considering three different scenarios, in which a comparison between the simulated values and those established in the management plans are compared. Important differences have been identified between the waste management programs of each municipality, specifically regarding the components of waste collection, transportation and disposal, participation of environmental reclaimers, and potential use of materials. These differences are fundamentally associated with the different administrative processes considered for each individual municipality. This research is a good starting point for the development of waste management models based on circular economy techniques, through the subsequent implementation of an office tool in depressed regions such as those studied.

Industry-Sponsored Medical Education — In the Quest for Professional Integrity and Legal Certainty

2007 ◽  
Vol 14 (4) ◽  
pp. 313-319
Author(s):  
Benedikt Buchner
Keyword(s):  
Medical Education ◽  
Self Regulation ◽  
State Regulation ◽  
General Question ◽  
Legal Certainty ◽  
European Directive ◽  
Starting Point ◽  
Good Starting Point ◽  
Advertising Law ◽  
The Right

AbstractIndustry-sponsored medical education is a much disputed issue. So far, there has been no regulatory framework which provides clear and definite rules as to whether and under what circumstances the sponsorship of medical education is acceptable. State regulation does not exist, or confines itself to a very general principle. Professional regulation, even though applied frequently, is rather vague and indefinite, raising the general question as to whether self-regulation is the right approach at all. Certainly, self-regulation by industry cannot and should not replace other regulatory approaches. Ultimately, advertising law in general and the European Directive 2001/83/EC specifically, might be a good starting point in providing legal certainty and ensuring the independence of medical education. Swiss advertising law illustrates how the principles of the European Directive could be implemented clearly and unambiguously.

scholarly journals Multiple Myeloma Inhibitory Activity of Plant Natural Products

Cancers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2678
Author(s):  
Karin Jöhrer ◽  
Serhat Sezai Ҫiҫek
Keyword(s):  
Multiple Myeloma ◽  
Natural Products ◽  
Myeloma Cell ◽  
Myeloma Cell Line ◽  
Antiproliferative Effects ◽  
Plant Natural Products ◽  
Starting Point ◽  
Human Myeloma Cell Line ◽  
Group A ◽  
Good Starting Point

A literature search on plant natural products with antimyeloma activity until the end of 2020 resulted in 92 compounds with effects on at least one human myeloma cell line. Compounds were divided in different compound classes and both their structure–activity-relationships as well as eventual correlations with the pathways described for Multiple Myeloma were discussed. Each of the major compound classes in this review (alkaloids, phenolics, terpenes) revealed interesting candidates, such as dioncophyllines, a group of naphtylisoquinoline alkaloids, which showed pronounced and selective induction of apoptosis when substituted in position 7 of the isoquinoline moiety. Interestingly, out of the phenolic compound class, two of the most noteworthy constituents belong to the relatively small subclass of xanthones, rendering this group a good starting point for possible further drug development. The class of terpenoids also provides noteworthy constituents, such as the highly oxygenated diterpenoid oridonin, which exhibited antiproliferative effects equal to those of bortezomib on RPMI8226 cells. Moreover, triterpenoids containing a lactone ring and/or quinone-like substructures, e.g., bruceantin, whitaferin A, withanolide F, celastrol, and pristimerin, displayed remarkable activity, with the latter two compounds acting as inhibitors of both NF-κB and proteasome chymotrypsin-like activity.

COVID-19, Business, and Human Rights

2021 ◽  
Vol 23 (5) ◽  
pp. 433-449
Author(s):  
Surya Deva
Keyword(s):  
Human Rights ◽  
Full Range ◽  
International Human Rights Law ◽  
Human Rights Law ◽  
International Human Rights ◽  
Economic Problems ◽  
Business And Human Rights ◽  
Starting Point ◽  
Good Starting Point ◽  
International Human

Abstract COVID-19 has affected the full range of human rights, though some rights holders have experienced a disproportionate impact. This has triggered debate about the respective obligations and responsibilities of states and business enterprises under international human rights law. Against this backdrop, this article examines critically whether the “protect, respect and remedy” framework operationalised by the UN Guiding Principles on Business and Human Rights is “fit for the purpose” to deal with the COVID-19 crisis. I argue that while the UNGPs’ framework provides a good starting point, it is inadequate to bring transformative changes to overcome deep-rooted socio-economic problems exposed by this pandemic. Realising human rights fully would not only require harnessing the potential of states’ tripartite obligations, but also move beyond limiting the responsibility of businesses to respect human rights.

Water Depollution Control : A Gateway to Reaction Monitoring and Analytical Chemistry

2021 ◽  
Author(s):  
Martin Tiano ◽  
Max Roose
Keyword(s):  
Analytical Chemistry ◽  
Undergraduate Students ◽  
Environmental Chemistry ◽  
Organic Pollutant ◽  
Internal Standard ◽  
Experimental Session ◽  
Reaction Monitoring ◽  
Starting Point ◽  
Good Starting Point ◽  
Magnetite Particles

<div>We present here an experimental session for undergraduate students, based on the reaction monitoring of the degradation of an organic pollutant (para-nitrophenol) by a Fenton-like reaction, catalysed by magnetite particles. <br></div><div>During the session, students realized a follow-up of the reaction by Gas Chromatography with an internal standard, and by UV-Visible spectrophotometry. <br></div>This session was a good starting point to numerous discussions about analytical chemistry, environmental chemistry.

What Neuroscience Can Tell about Intuitive Processes in the Context of Perceptual Discovery

2006 ◽  
Vol 18 (12) ◽  
pp. 2077-2087 ◽  
Author(s):  
Kirsten G. Volz ◽  
D. Yves von Cramon
Keyword(s):  
Initial Guess ◽  
Future Research ◽  
Starting Point ◽  
Sensory Modalities ◽  
Direct Contrast ◽  
Good Starting Point ◽  
Lateral Portion ◽  
Definition Of ◽  
Conscious Attention ◽  
Potential Content

According to the Oxford English Dictionary, intuition is “the ability to understand or know something immediately, without conscious reasoning.” Most people would agree that intuitive responses appear as ideas or feelings that subsequently guide our thoughts and behaviors. It is proposed that people continuously, without conscious attention, recognize patterns in the stream of sensations that impinge upon them. What exactly is being recognized is not clear yet, but we assume that people detect potential content based on only a few aspects of the input (i.e., the gist). The result is a vague perception of coherence which is not explicitly describable but instead embodied in a “gut feeling” or an initial guess, which subsequently biases thought and inquiry. To approach the nature of intuitive processes, we used functional magnetic resonance imaging when participants were working at a modified version of the Waterloo Gestalt Closure Task. Starting from our conceptualization that intuition involves an informed judgment in the context of discovery, we expected activation within the median orbito-frontal cortex (OFC), as this area receives input from all sensory modalities and has been shown to be crucially involved in emotionally driven decisions. Results from a direct contrast between intuitive and nonintuitive judgments, as well as from a parametric analysis, revealed the median OFC, the lateral portion of the amygdala, anterior insula, and ventral occipito-temporal regions to be activated. Based on these findings, we suggest our definition of intuition to be promising and a good starting point for future research on intuitive processes.

scholarly journals Using crocodilian tails as models for dinosaur tails

2015 ◽  
Author(s):  
Heinrich Mallison ◽  
Michael Pittman ◽  
Daniela Schwarz
Keyword(s):  
Sensitivity Analysis ◽  
Morphological Data ◽  
Muscle Forces ◽  
Limited Knowledge ◽  
Starting Point ◽  
Good Starting Point ◽  
Methodological Problems ◽  
Parameter Ranges

The tails of extant crocodilians are anatomically the closest approximation of the tails of non-avian dinosaurs, and therefore a good starting point for any reconstruction of non-avian dinosaur tail muscles. However, we here demonstrate some methodological problems using crocodile tails, firstly regarding the general reconstruction of tail mobility from osteology, secondly for the reconstruction of tail musculature for the quantification of muscle forces, especially the m. caudofemoralis longus, and thirdly with respect to the anatomical differences between crocodilians and non-avian dinosaurs, especially in relation to the reconstruction of m. caudofemoralis brevis. Our results show that, given the current limited knowledge of crocodilian tails, volumetric reconstructions should be created on the basis of more gross morphological data than is usually used, and that biomechanical studies should include sensitivity analysis with greater parameter ranges than often applied.

scholarly journals Light-Excited Ag-Doped TiO2−CoFe2O4 Heterojunction Applied to Toluene Gas Detection

Nanomaterials ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 3261
Author(s):  
Wenhao Wang ◽  
Lu Zhang ◽  
Yanli Kang ◽  
Feng Yu
Keyword(s):  
Diffuse Reflectance ◽  
Gas Sensing ◽  
Limit Of Detection ◽  
Electron Hole ◽  
Detection Range ◽  
Response Recovery ◽  
Test Conditions ◽  
Sensing Material ◽  
Starting Point ◽  
Good Starting Point

(1) Background: Toluene gas is widely used in indoor decoration and industrial production, and it not only pollutes the environment but also poses serious health risks. (2) Methods: In this work, TiO2−CoFe2O4−Ag quaternary composite gas-sensing material was prepared using a hydrothermal method to detect toluene. (3) Results: The recombination of electron–hole pairs was suppressed, and the light absorption range was expanded after constructing a heterojunction and doping with Ag, according to ultraviolet–visible (UV–vis) diffuse reflectance spectra and photoluminescence spectroscopy. Moreover, in the detection range of toluene gas (3 ppm–50 ppm), the response value of TiO2−CoFe2O4−Ag increased from 2 to 15, which was much higher than that of TiO2−Ag (1.7) and CoFe2O4−Ag (1.7). In addition, the working temperature was reduced from 360 °C to 263 °C. Furthermore, its response/recovery time was 40 s/51 s, its limit of detection was as low as 10 ppb, and its response value to toluene gas was 3–7 times greater than that of other interfering gases under the same test conditions. In addition, the response value to 5 ppm toluene was increased from 3 to 5.5 with the UV wavelength of 395 nm–405 nm. (4) Conclusions: This is primarily due to charge flow caused by heterojunction construction, as well as metal sensitization and chemical sensitization of novel metal doping. This work is a good starting point for improving gas-sensing capabilities for the detection of toluene gas.

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