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Does left atrial appendage occlusion influence left atrial hemodynamics? Pilot result...
Samuel Heuts
John Heijmans

Samuel Heuts

and 3 more

February 05, 2021
Introduction Although left atrial appendage (LAA) obliteration is the cornerstone of stroke prevention in surgical treatment of atrial fibrillation (AF), little is known about its direct impact on hemodynamics. In the current pilot study, we evaluated the hemodynamic effect of LAA closure by clipping in patients undergoing hybrid AF ablation. Methods Seven patients with paroxysmal or persistent AF were included. Hemodynamic and intracardiac pressure measurements such as systemic, pulmonary artery (PA), central venous and LA pressure, cardiac output and indexed left ventricular stroke volume (LVSVi) were measured directly before (T0) and after (T1), and 10 minutes after (T2) LAA closure. Results Of the 7 patients (median 66 yrs), 5 were in AF at the time of incision. There were no differences between T0 and T1, T1 and T2 and T0 and T2 for LA pressure, mean PA pressure, LVSVi and other hemodynamic parameters such as central venous oxygenation and pressure, or systemic arterial pressure. Conclusion In this pilot study, the direct hemodynamic effect of LAA closure is evaluated for the first time. Clipping of the LAA is safe and does not directly affect hemodynamic and intracardiac pressures.
Aerodynamics in the classroom Curriculum Unit: Lesson 2 "Streaming Across Airfoil Sha...
Ahmed Samir
STEM.org

Ahmed Samir

and 1 more

February 18, 2021
Suggested Time: 50 minutesGrade Level: High SchoolNGSS StandardsHS-PS2-1. Analyze data to support the claim that Newton’s second law of motion describes the mathematical relationship among the net force on a macroscopic object, its mass, and its acceleration.HS-PS2-2. Use mathematical representations to support the claim that the total momentum of a system of objects is conserved when there is no net force on the system.Science and Engineering PracticesPlanning and Carrying out InvestigationsAnalyzing and Interpreting DataConstructing Explanations and Designing SolutionsLesson OverviewIn this lesson students will be introduced to the idea behind using airfoil shapes to generate lift and the parameters that define an airfoil shape. Students will learn some of the terminologies related to flight and test the process using simple prototype of an airfoil shape. Students will use their data literacy skills to describe the effect of changing the angle of attack on the performance of the airfoil shape.VocabularyAirfoil                                                       Angle of attackLiftDragCamberChordLeading edgeTrailing edgeObjectives and Learning OutcomesStudents will define how an airfoil shape looks like.Students classify and show the different shapes of an airfoil.Students will illustrate the meaning of lift and drag forces.Students will construct a simple paper airfoil shape and test it.Students will discover and analyze the effect of changing the angle of attack on the airfoil.Required Project MaterialsA4 and A3 paper sheetsTapeRulerScissorsstrawsMarkerstringHair drierComputer with internet accessAngle of attack STEAM JournalMultimedia Resources"The basics of Airfoils" https://www.youtube.com/watch?v=7Lb7nx3Jv20&t=37s"What is an angle of attack?" https://www.youtube.com/watch?v=t0tCRq2JedY"Airfoil dimensions"  https://www.grc.nasa.gov/www/k-12/airplane/geom.html"NASA Airfoil Simulator" https://www.grc.nasa.gov/www/k-12/airplane/foil3.htmlOptional Multimedia resources"NACA Airfoil Series" https://www.nasa.gov/image-feature/langley/100/naca-airfoils"History of Airfoil Deign" https://www.century-of-flight.net/history-of-the-airfoil/Before the lesson/Background informationStudents should have gained a knowledge from the previous lesson about the forces of flight and parts of an airplane as well as other concepts like gravity and pressure.Lesson PlanEngage (Estimated time: 5 minutes) Use the video link in the Multimedia resources section labelled as "The basics of airfoil" to engage the students of how airfoil shape looks like. By the end of the video ask the students about the different parameters that define how an airfoil shape looks like. Invite a student to draw the shape of an airfoil on the board and label the different parameters (show the students the image in the link labelled as "Airfoil dimensions" in the multimedia resources)Explore (Estimated time: 20 minutes)Ask the students to work in groups in order to use the materials listed in the required project material section to create a simple wing shape with an airfoil cross-section. Students will need to use ruler to divide the paper sheet into half and label the midpoint of the wing. Students are also supposed to use straw to hold the wing along the midpoint using a string. The teacher will be passing by the groups of students to scaffold and give further instruction to help them.Next, students are supposed to use hair drier in order to direct air towards their model and record their observations. In group discussions, students are supposed to discuss their observations and try to define the meaning of lift and drag forces produced on the surface of the wing.
UV tolerance and sustained non-photochemical quenching in a desert moss
Jenna T. B. Ekwealor
Theresa Clark

Jenna T. B. Ekwealor

and 7 more

July 14, 2020
Desert mosses withstand intense sunlight while desiccated and metabolically inactive. We used in situ field experiments to uncover the effects of natural and reduced levels of UV radiation on maximum Photosystem II (PSII) quantum efficiency (Fv/Fm) and on the relative abundance of photosynthetic pigments and antioxidants in Syntrichia caninervis. We tested the hypothesis that if UV is a stressor, reduction of natural UV levels will result in increased photosynthetic efficiency, but that such reduction will de-harden plants and increase vulnerability to PSII damage with UV exposure. We also measured photosynthetic efficiency over a simulated winter recovery period to assess sustained non-photochemical quenching (NPQ) and its subsequent relaxation. Finally, we measured the effect of UV reduction on photosynthetic pigment and antioxidant abundance. All field-collected plants had low Fv/Fm at collection but recovered over eight days in winter conditions. Plants in the low-UV treatment had lower Fv/Fm during recovery than those exposed to natural UV levels and had higher zeaxanthin, lutein, tocopherols, and a higher ratio of chlorophyll a to chlorophyll b. Natural S. caninervis undergoes sustained NPQ that takes days to relax and for efficient photosynthesis to resume. Reduction of UV radiation from sunlight has adverse effects on recovery of Fv/Fm.
CULTURE (YORÙBÁ) AS A MEANS OF DE-ESCALATING CONFLICT AND MAINTAINING PEACE   
Akintayo Sunday Olayinka

Akintayo Sunday Olayinka

December 15, 2020
Most works in peace and conflict studies concern interventions in conflict situations – such as conflict management – or projects seeking to sustain peace after a conflict, such as conflict resolution, conflict transformation, and peace education. However, using a peace lens, this study affirms culture as one of the means the Yorùbá utilize to sustain peace in their community. The paper first ascertains the presence of conflict and proceed to discuss how some features of Yorùbá culture facilitate harmony as evidenced in the research findings. Note: This article is based on a primary research among the Yorùbá of southwest Nigeria within 2015 to 2020, the bulk of which is taken from chapter 5 of the dissertation. A few amendments were made to suit the requirement of this journal publication.
The nascent case for adopting Jupyter notebooks as a pedagogical tool for interdiscip...
Chiin-Rui Tan

Chiin-Rui Tan

January 12, 2021
Many societal opportunities and challenges, both current and future, are either inter- or transdisciplinary in nature. Focus and action to cut across traditional academic boundaries has increased in research and, to a less extent, teaching. One successful collaboration has been the augmentation of fields within the Humanities, Social Sciences, and Arts by integrating complementary tools and methods originated from STEM. This trend is gradually materializing in formal undergraduate and secondary education.The proven effectiveness of Jupyter notebooks for teaching and learning STEM practices gives rise to a nascent case for education seeking to replicate this interdisciplinary design to adopt notebook technology as the best pedagogical tool for this job. This article presents two sets of data to help argue this case.The first set of data demonstrates the art of the possible. A sample of undergraduate and secondary level courses showcases existing or recent work of educational stakeholders in the US and UK who are already pioneering instruction where computational and data practices are integrated into the study of the Humanities, Social Sciences, and Arts, with Jupyter notebooks chosen as a central pedagogical tool. Supplementary data providing an overview of the types of technical material covered by each course syllabi further evidences what interdisciplinary education is perceived to be or is already feasible using this Jupyter technology with student audiences of these levels.The second set of data provides more granular, concrete insight derived from user experiences of a handful of the courses from the sample. Four instructors and one student describe a range of pedagogical benefits and value they attribute to the use of Jupyter notebooks in their course(s).In presenting this nascent case, the article aims to stimulate the development of Jupyter notebook-enabled, computational data-driven interdisciplinary education within undergraduate and secondary school programs.
Hertzsprung-Russell Diagrams: Nuclear Fusion Reactions in the Main Sequence 
Armandt Erasmus

Armandt Erasmus

December 05, 2020
IntroductionDuring the nineteenth-century, the Harvard College Observatory performed many photographic spectroscopic surveys of stars. This produced spectral classifications for roughly 225,000 stars, which created the Henry Draper Catalogue. Ejnar Hertzsprung realised that narrow lined stars had smaller proper motions compared to other stars of the same spectral classification. He was then able to estimate the stars’ absolute magnitudes\cite{1} by computing their secular parallaxes as a result of the difference of proper motions.DefinitionsBefore we start constructing and analysing a Hertzsprung-Russell Diagram, we should familiarise ourselves with some of the words used in this paper.Firstly, Absolute Magnitude (\(M\)) is a measure of the luminosity of a celestial object, on an inverse logarithmic astronomical magnitude scale. It is further defined to be equal to the apparent magnitude that the object would have if it were viewed from a distance of exactly 10 parsecs without extinction of its light.Apparent Magnitude (\(m\)) is a measure of the brightness of a celestial object observed from Earth. This value is dependent on factors such as the extinction of the body’s light, its intrinsic luminosity and its distance from Earth. We state a relationship, the brighter an object, the lower its magnitude value.Luminosity (\(L\)\(\circ\) or \(L\)*) refers to the absolute measure of radiated electromagnetic power emitted by a light-emitting object. We are interested in both the solar luminosity, denoted by \(L\)\(\circ\) and the stellar luminosity, denoted by \(L\)* of a particular star.Lastly, we define the Hertzsprung-Russell Diagram as a scatter plot of stars which shows the relationship between the stars’ absolute magnitudes or luminosities versus their stellar classifications or effective temperatures.Absolute MagnitudeWe know that absolute magnitude is measured by a body’s luminosity, which provides us with the relationship between Absolute Magnitude and Luminosity, which states that the more luminous an object is, the smaller the numerical value of its absolute magnitude. In terms of variables, we can express this relationship by the following:A difference of n magnitudes ( in absolute magnitude ) corresponds to a luminosity ratio of \(100^{\frac{n}{5}}\). In a general sense, subscripts are used alongside \(M\) to represent the filter band used for the specific measurement, e.g. \(M\)V for measurements in the V-Band. We generalise this over all wavelengths with an object’s bolometric magnitude. By applying a bolometric correction\cite{2a}, we can convert absolute magnitudes in specific filter bands to its absolute bolometric magnitude.\[M_{bol}=M_v+BC\]Where BC is the Bolometric Correction, needed to factor in specific types of radiation by celestial bodies.Apparent Magnitude A numerical scale by Hipparchus describes the brightness of stars that appear in the night sky, where \(m\) = 1 is assigned to the brightest stars and \(m\) = 6\cite{3} assigned to the dimmest stars.The equation,\[100^{\frac{mM}{5}}=\frac{F}{F_{10}}=\left(\frac{d}{10pc}\right)^2\]relates objects within the neighbourhood of the Sun, where their brightness differs by a factor of 100 for \(m\) and \(M\) from any distance \(d\). The following equation is derived, given that \(d\) is measured in parsecs,\[M=m-5\log_{10}\left(d_{pc}\right)+5\]  Which when simplified produces,\[M=m-5\left(\log_{10}d_{pc}-1\right)\]This equation can also be written in two other forms,In terms of stellar parallax.(1) \[M=m+5\left(\log_{10}p+1\right)\]Where a distance modulus is known:(2) \[M=m-\mu\]For this paper, we will only be concerned with equation (1).Gathering DataThe following table was generated by using data available from VizieR. The Vmag column represents the H5 V Johnson magnitudes, Plx the Trigonometric Parallax, B-V the Johnson B-V Colours and finally SpType to represent all the Spectral Types.
My Escape from the Lab: Scientific Publishing
Matteo Cavalleri

Matteo Cavalleri

February 13, 2021
This talk explores roles for postdoctoral STEM researchers in the publishing industry. By sharing my experience I hope to enable a broader understanding of the different roles inside the editorial office of academic journals and the skills required for editorial positions posted by commercial and society publishers.
Mach-Zehnder Interferometer Design Proposal
Kevin Chen

Kevin Chen

January 24, 2021
This report describes the design of Mach-Zehnder Interferometer, including its design background, components used, and physical parameters.
Tourette syndrome research highlights from 2020
Andreas Hartmann
Yulia Worbe

Andreas Hartmann

and 3 more

January 16, 2020
Copyright © 2020-2021, the authors. AH: ORCiD 0000-0002-0335-984XYW: ORCiD 0000-0001-5903-9370CD: ORCiD 0000-0002-7212-9554
History of canids in Chile and impacts on prey adaptations
Benjamín Silva
Meredith Root-Bernstein

Benjamín Silva

and 1 more

January 11, 2021
Artiodactyl prey species of Chile, especially guanacos (Lama guanicoe) are reported to be very susceptible to predation by pack hunting feral dogs. It has been previously suggested that guanacos and endemic South American deer may have evolved in the absence of pack-hunting cursorial predators. However, the paleoecology of canid presence in southern South America and Chile is unclear. Here, we review the literature on South American and Chilean canids, their distributions, ecologies and hunting behaviour. We consider both wild and domestic canids, including Canis familiaris breeds. We establish two known antipredator defense behaviours of guanacos: predator inspection of ambush predators, e.g. Puma concolor, and rushing at and kicking smaller cursorial predators, e.g. Lycalopex culpaeus. We propose that since the late Pleistocene extinction of hypercarnivorous group-hunting canids east of the Andes, there were no native species creating group-hunting predation pressures on guanacos. Endemic deer of Chile may have never experienced group hunting selection pressure from native predators. Even hunting dogs (or other canids) used by indigenous groups in the far north and extreme south of Chile (and presumably the center as well) appear to have been used primarily within ambush hunting strategies. This may account for the susceptibility of guanacos and other prey species to feral dog attacks. We detail seven separate hypotheses that require further investigation in order to assess how best to respond to the threat posed by feral dogs to the conservation of native deer and camelids in Chile and other parts of South America.
You Are More Than What You Eat: Differential Enrichment of Microbiome Functions Acros...
Melissa Ingala

Melissa Ingala

and 5 more

February 02, 2021
Animals evolved in a microbial world, and their gut microbial symbionts have played a role in their ecological diversification. While many recent studies have reported patterns of co-diversification of hosts and their gut microbes, few studies have directly examined the functional contributions of these microbes to the dietary habits of their hosts. Here, we examined functional enrichment of metabolic pathways in the gut bacteria of 545 bats belonging to 60 species and five terrestrial feeding niches. We found that hosts of different dietary guilds had differential enrichment of bacterial functions that may be adaptive to their respective diets, and that metagenome functions were highly predictive of host feeding guild. We detected little evidence of host phylogenetic effect on gut metagenome composition, suggesting that diet likely overrides host evolutionary history in structuring functional pathways in the gut metagenome. Our results further suggest that bats may have evolved to partially rely on their gut microbes to fulfill critical metabolic pathways, including essential amino acid synthesis, fatty acid biosynthesis, and the generation of cofactors and vitamins essential for proper nutrition. This work represents a comprehensive and novel insight into the contribution of gut microbes to vital metabolic processes in a diverse Order of wild mammals.
Guano Information Pipeline in several Five Paragraph Essays
Miranda Galey

Miranda Galey

March 21, 2019
Diet is a recognized factor in microbial diversity of the gut microbiome but is seldom investigated thoroughly outside of captive animal studies. In fecal samples where the signal of evolutionary history is weak, diet is often suggested as an alternative driving factor, but this assertion is not supported by data on an individual level. Here I propose to connect the gut microbiota of individual insectivorous bats to a precise account of their diet using 16S rRNA sequencing of the bacterial community and DNA barcoding of the COI mitochondrial gene. Several alternative hypotheses are presented to account for variation in the gut microbiota of bats with similar prey composition, including species level variation, sex, reproductive state, foraging habitat, and white nose syndrome survivorship. This study incorporates field collection and identification of bat subjects, laboratory methods including DNA extraction, amplification of three markers, and sequencing on the MiSeq Illumina platform. Analysis includes an extensive bioinformatics toolbox, spatial analysis, and mathematical modeling in a generalized hidden markov model framework.
MatterReview: Neonatal Sepsis
MedMatter

MedMatter

October 19, 2017
Neonatal sepsis is the very important cause of neonatal morbidity and mortality, especially in newborns with risk factors such as premature birthThe neonatal sepsis can be divided into 2 groups: early onset and late onset each with their own distinctive causes, risk factors and severityEarly-onset sepsis usually caused by vertical infection from the complicated birth such as prolong PROM > 18hr or maternal chorioamnionitis. GBS and E.coli is the most common but both gram-negative and gram-positive bacteria can be the causative agents. The symptom is very nonspecific and the laboratory adjunct is essential. The management include initially emprical ATB and deescalate according to microbiology results. The ATB need to be selected carefully espcially when consider the penetration to the CNS. Established Dosage and Duration must be follow to ensure the most effective results
(0005) Practical possibilities of pumped-storage power plants implementation in liqui...
Peczkis Grzegorz

Peczkis Grzegorz

February 01, 2021
In the paper the theoretical basis of pumped-storage power plant operation is presented. Working conditions of hydraulic machines in these kinds of objects are described and examples are given. The Czech research results as well as German theoretical analyses on the topic of water energy storage in underground mines are characterized. The conditions for building pumped-storage power plant in Polish underground coal mines, including liquidated ones, are determined. Analysis of parallel operation of multistage centrifugal pumps, dedicated to the mine drainage system, manufactured and operated commonly in Poland is presented. The main dimensions calculations of two multistage centrifugal pumps (power of 10 MW and 25 MW), dedicated for selected parameters, are presented.
Research on construction engineering safety Risk Control based on IAHP-TOPSIS
Minggang DU
Tongyin HAN

Minggang DU

and 2 more

February 08, 2021
A document by Minggang DU, written on Authorea.
STEMpreneurship
Jerome McQueen, PE

Jerome McQueen, PE

January 30, 2021
CONCEPTSTEMpreneurship is a three-phased STEM program that introduces students to basic STEM concepts through assembling STEM kits, then coming up with their own conceptual design through the engineering design process, then lastly exposure to entrepreneurship and teaching them how to enter their product design into the business marketplace. The culmination of STEMpreneurship is the "Shark Tank-like" competition where the students present their product design to would-be investors attempting to obtain funding for their design.Discalimer: This program can be lengthen and modified into a 6,8, or 12 week program.OVERALL PROGRAM OBJECTIVESStudents will learn the following science concepts by assembling STEM kits:Basic electric circuits;Solar Energy;Air propulsion;Structures; andWind Energy.Students will learn to design their own product through the engineering design process;Students will learn basic entrepreneurship and business skills;Students will use mathematics to develop their investor pitch to would-be investors;Students will learn to use technology to develop their product design and presentation;Students  will learn to collaborate in a team environment to develop the presentations to would-be investors.Students will learn to connect STEM concepts to real-world applications.LESSON 1: STEM CONCEPTSSuggested Time: 55 Minutes (Per STEM Kit)OVERVIEWStudents will learn various STEM concepts such as electric circuits, solar energy, air propulsion, structures, and wind energy by assembling STEM kits provided by AcaSTEMics, LLC. Each session is for one STEM kit. The following STEM kits correspond to the following STEM concept:1. Basic electric circuits - Table Top Lamp2. Solar Energy - Solar Fan3. Air Propulsion - Twin Engine Electric Plane4. Structures - Marshmallow Building5. Wind Energy - Wind TurbineThe LessonPART 1: STEM KIT ASSEMBLY (40 MINUTES, per kit)1. STEM Kits are distributed to the students.
should be atmospheric circulation responsible for the increasing summer heatwave?
Yongli He

Yongli He

March 06, 2017
  Abstract 200 vs 300key pointssummer heatwaves have a strong relationship with Rossby waves, however, which is weaker than summer coldspellsummer heatwaves are decoupling with strong Rossby wave amplitudesummer heatwaves with strong Rossby wave amplitude are becoming strongerIntroduction1, cluster high temperature events increase under RCP4.50 scenario \cite{Zhou_2020}data and methodresultconclusion and discussion
量子力学の観測問題と哲学的ゾンビ(執筆中)
quantumtimemeasure

quantumtimemeasure

March 23, 2019
はじめに 本稿では、コペンハーゲン解釈、多世界解釈に代わる新しい量子力学の解釈を示そうと思う。新解釈に名前はまだない。新解釈は、波束の収束・射影仮説が不要な点で、多世界解釈に近い解釈であるが、遠い銀河を含めて世界が分かれるとは考えないことから、いわゆる多世界解釈とは異なる。EverettのもとのRelative-State Formulationにより近いものと考えられる。 本稿の検討は、「哲学的ゾンビ」のタイトルが示すように、哲学・形而上学に属するものであり、自然科学に属するものではない。本稿は、実験結果に関する限り、コペンハーゲン解釈に基づく量子力学(場の理論を含む)が正しいことを前提としている。そのため、新解釈によって、実験結果について新しい予言ができるようになることはない。異なる考え方があり、そのいずれが正しいか実験で確認しようがないとき、いずれの考え方を選ぶか考察することは、科学ではなく、哲学と私は考えている。したがって、本稿の考察は哲学である。自然科学の理論としては、コペンハーゲン解釈と新解釈・本稿の間に違いはなく、同じものである。 ただし、マクロな巨視的な状態に対しても、重ね合わせの原理が成り立つと考える。重ね合わせの原理が成り立つミクロな状態と重ね合わせのないマクロな状態の境界は知られていないため、これはコペンハーゲン解釈と矛盾するものでない。 本稿の構成(予定)は以下のとおりである。まず、新解釈は、随伴現象説に基づくものであるため、第1章で、まずその説明から始める。次に、古典的な世界がどのようにして量子力学、ヒルベルト空間から生み出されるのかの仮説を第2章及び第3章で述べる。そして、第4章で、その古典的な世界と随伴現象説の関係を述べる。第5章で、存在とは何かについての、私見を科学的実在論を中心に述べる。また、本稿はギリシア時代の原子論と同様に科学的な根拠がほぼ存在しない考察であるが、それが科学的な根拠を持つものになる可能性について整理して述べる。最後に第6章で、新解釈が倫理に与える影響について考察する。
Religious Hermeneutics as a Means of De-escalating Conflict and Sustaining the Peace 
Akintayo Sunday Olayinka

Akintayo Sunday Olayinka

January 13, 2021
This paper presents the roles the interpretations of religious text(s) and understanding of religion play in the sustainability of peace among the Yorùbá people of southwest Nigeria. The Yorùbá’s way of interacting and practising religion has remained moderately amiable over the last two centuries. With attention on Yoruba Christians and Muslims, this author examines some specific religious concepts and social values that have been useful in guiding the two religions to retain their peace or return to dialogue table to refrain from violence and keep the peace. Please note: The bulk of this article is taken from chapter 8 of the author's doctoral dissertation with a few amendments to suit this journal. Keywords: Christian-Muslim relations, peace studies, African Yoruba, religious – ethics – culture – values. 
Hypothesis: Mycotoxins Causing Amyotrophic Lateral Sclerosis
William Reid

William Reid

August 16, 2020
Amyotrophic Lateral Sclerosis(ALS) remains a terminal disease without an established etiology for the majority of patients. The dominant theory of ALS before 1970’s was the presence of a poison. One of the primary means of treating patients with a toxic exposure has been plasma exchange, but plasma exchange of ALS patients failed to alter the clinical course. The failure of plasma exchange assumes the patient is no longer exposed to the poison. If the exposure to poisons continued, then plasma exchange alone would fail. I found laboratory evidence of a poisoning in every patient with ALS examined. A search for specific poisons found evidence of mycotoxins. Treatment with antifungal agents corrected the laboratory findings. All of the ALS patients had evidence of immune suppression. There is mounting evidence that many mycotoxins cause both neurotoxicity and immune suppression. These mycotoxins may be able to explain the full spectrum of pathology in ALS without a secondary event.
Nuovi processi biologici a membrane per la depurazione sostenibile delle acque reflue
Stefano Cairone

Stefano Cairone

October 24, 2020
I bioreattori a membrana (MBR) combinano il processo di degradazione biologica a fanghi attivi e il processo fisico di filtrazione con membrane, costituendo un sistema di trattamento avanzato delle acque reflue. Tra i numerosi vantaggi  di questa tecnologia, assume particolare importanza l’elevata efficienza depurativa: gli MBR garantiscono la rimozione sia di contaminanti convenzionali che di contaminanti emergenti. Tuttavia, gli MBR presentano degli svantaggi legati principalmente agli elevati costi di investimento e di gestione degli impianti e al controllo del fouling. L’introduzione dei bioreattori a membrana dinamica auto-formante (SFDMBR), basati sull’utilizzo di un materiale di supporto a pori grossolani a basso costo per la formazione di una membrana dinamica auto-formante, consente di ottenere elevate prestazioni depurative a fronte di ridotti costi di investimento. Gli elettro-bioreattori a membrana (e-MBR) combinano processi elettrochimici nei sistemi MBR, con conseguente incremento dell’efficienza depurativa e riduzione del fouling. Combinando la tecnologia SFDMBR con quella e-MBR si ottiene un sistema ibrido estremamente innovativo: l’elettro-bioreattore a membrana dinamica auto-formante (e-SFDMBR).
Calculating CsCl and GB+DNA volumes to reach a target density for a density gradient
Roey Angel

Roey Angel

February 03, 2021
For preparing a CsCl density gradient one typically mixes a high-density solution of CsCl (7.163 M) with an aqueous buffer solution to reach a target density. For DNA separation in SIP studies this is typically 1.725 g ml-1. Despite the simplicity of the problem, different formulae appeared in the literature, leading to slightly different end values. Most notably, the famous publication by \citealp{Neufeld_2007} uses a constant---1.52---instead of a variable that would represent the density of the mixture. The source of this constant appears to be from the classical book Centrifugal Separations: Molecular and Cell Biology by \citealp{1985}, where it is used for a specific case only.While the practical implications are small so long as one tries to create a solution with a density of 1.725 g ml-1 (although the resulting value is still wrong), the deviations become significant the further the target density deviates from this value.  
Interactive Supercomputing with Jupyter
Rollin Thomas
Shreyas Cholia

Rollin Thomas

and 1 more

December 16, 2020
Rich user interfaces like Jupyter have the potential to make interacting with a supercomputer easier and more productive, consequently attracting new kinds of users and helping to expand the application of supercomputing to new science domains. For the scientist-user, the ideal rich user interface delivers a familiar, responsive, introspective, modular, and customizable platform upon which to build, run, capture, document, re-run, and share analysis workflows. From the provider or system administrator perspective, such a platform would also be easy to configure, deploy securely, update, customize, and support. Jupyter checks most if not all of these boxes. But from the perspective of leadership computing organizations that provide supercomputing power to users, such a platform should also make the unique features of a supercomputer center more accessible to users and more composable with high performance computing (HPC) workflows. Project Jupyter's core design philosophy of extensibility, abstraction, and agnostic deployment, has allowed HPC centers like NERSC to bring in advanced supercomputing capabilities that can extend the interactive notebook environment. This has enabled a rich scientific discovery platform, particularly for experimental facility data analysis and machine learning problems.  
Bitcoin Blockchain Clustering Analysis for Ransomware Detection
Thiago R. C. de Lima

Thiago R. C. de Lima

February 01, 2021
Bitcoin is the most popular digital currency. It is not controlled by any sort of central bank or government institution and is the preferred payment method requested by cyber criminals through ransomware.  This type of malware encrypts a victim's files and forces them to pay a ransom in order to regain access. In this short paper, Bitcoin transaction data of tenyears is analyzed by generating a K-Means clustering model, using it to predict each sample's cluster, and then creating a confusion matrix and evaluating the results (Rand Score).
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