text:
Srijna Singh1 , Mohammad Danish2 , Kaushik Saha3 , Vinayak Ranjan4
1, 2, 3Bennett University, Greater Noida, India
4Indian Institute of Technology, New Delhi, India
Vibroengineering PROCEDIA, Vol. 21, 2018, p. 125-130. https://doi.org/10.21595/vp.2018.20396
Received 19 November 2018; accepted 26 November 2018; published 13 December 2018
Copyright © 2018 Srijna Singh, et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Singh Srijna, Danish Mohammad, Saha Kaushik, Ranjan Vinayak Numerical simulation of Vortex-shedding from NACA4418 hydrofoil. Vibroengineering PROCEDIA, Vol. 21, 2018, p. 125-130. https://doi.org/10.21595/vp.2018.20396
Table of Contents Download PDF References
To get better understanding of vortex shedding mechanism, we conducted numerical simulation on NACA 4418 hydrofoil at an angle of attack of 12° for 2D incompressible flow. The numerical method consists of transient, finite volume method using Transient SST turbulent model to capture the turbulent wake flows. At high Reynolds number the occurrence of 2D structures of shed vortices and the modulation of vortex-induced frequency are investigated. The lift, pressure and skin friction coefficients of hydrofoil were studied.
Keywords: NACA 4418, hydrofoil, Vortex shedding, transition SST.
Flow over a two-dimensional hydrofoil shows different hydrodynamics and flow dynamics characteristics which basically depends upon the shape of hydrofoil and free stream parameters.
The shape and the angle of attack of hydrofoil determines the pressure distribution which corresponds to the change in lift and drag forces [1]. The parameters which influences the flow dynamics are Mach number, angle of attack (AOA) and Reynolds number [2]. At low Reynolds number and at small AOA the flow remains laminar near the leading edge of hydrofoil but at higher Reynolds number and increasing AOA the fluid starts to segregate near the rear edge forming vortices. The trailing edge separation moves upstream, and the separated flow grows with increasing angle of attack. This flow separation and formation of vortices make the flow oscillating and this phenomenon is called vortex shedding.
The phenomenon of vortex shedding can be seen everywhere near us such as: wind flow around driving car, ocean current interaction with offshore structures, on aircrafts. Leonardo da Vinci was the first one to describe concept of vortex formation in a flow around bluff bodies. Vortex are the rotating or swirl occurs when the water current is hinders by an obstruction, often turbulent flow [3, 4]. The major difficulty to simulate these flows lies in capturing the complex behaviour of the oscillating flow. However, with the emergence of powerful computers, computational methods like finite difference method (FDM), finite volume method (FVM), finite elements method (FEM) it became easy to investigate various fluid dynamics problems. It has been observed that vortex shedding is unsteady flow which produces separate stream along most of the surface [5].
In this work the transient turbulent flow over a NACA4418 hydrofoil profile at Re= 99700 and angle of attack ∝= 12° is simulated using a finite volume method (FVM) in Ansys Fluent. The pressure coefficient and skin friction coefficient were computed as function of chord length of hydrofoil. The purpose of this paper is to study the physics behind the vortex shedding for transient simulations.
2. Governing equations
The movement of 2-D viscous incompressible fluid flow over the hydrofoil is governed by the continuity equation and Navier-Stokes equations:
∂ u ∂ x + ∂ v ∂ y = 0 ,
∂ u ∂ t + u ∂ u ∂ x + v ∂ u ∂ y = - ∂ P ∂ x + 1 R e ∂ 2 u ∂ x 2 + ∂ 2 u ∂ y 2 ,
∂ v ∂ t + u ∂ v ∂ x + v ∂ v ∂ y = - ∂ P ∂ y + 1 R e ∂ 2 v ∂ x 2 + ∂ 2 v ∂ y 2 ,
where Re=u0D/v is the Reynolds number, v is the velocity in y-direction and u is the velocity in x-direction, ρ is the mass density, v is the kinematic viscosity, t is the time, p is the pressure and u0 is initial value of velocity provided at the inlet along with zero relative velocity to boundary condition on the solid walls [6, 7]. To solve the external flows, suitable initial boundary conditions must be provided to start the solution. Lifting bodies like hydrofoil are designed to provide large forces in the direction of perpendicular to direction of flow and low drag. The coefficient of drag CD, coefficient of lift.
C L , Strouhal number St coefficient of pressure CP, skin friction coefficient Cf and vorticity ω→ on solid body are defined as following:
C L = L 1 2 ρ u 0 2 c , C D = D 1 2 ρ u 0 2 c , S t = f d u 0 ,
C P = P x - P ∞ 1 2 ρ u 0 2 , C f = τ ω 1 2 ρ u 0 2 , ω → = ∇ × u → ,
where L and D is lift and drag force respectively whereas, d is the characteristic dimension, f is frequency if oscillations and c is the chord length of hydrofoil.
2.1. Turbulent model
Transition shear stress transport (SST) model is being used for transient simulation that basically defines the coupling of SST k-ω equation with other two transport equations, one is used for intermittency and other for the transition onset standard, with respect to Reynolds number for momentum-thickness [8]. The Transition SST model is designed for flows with a defined non-zero freestream velocity. The local turbulence intensity, Tu with k as the turbulent energy is as below:
T u = 100 U 2 3 k .
3. Computational procedure
3.1. Geometry formation and mesh generation
The steady and transient two-dimensional flow over NACA4418 hydrofoil at an angle of attack (AOA) of 12° was simulated using finite volume method (FVM) code in Ansys Fluent. To generate the profile of hydrofoil NACA airfoil generator database is being used. Two types of meshes were considered in this work. One was C-mesh type, which is multiblock structure mesh that consists of semicircle grid that follows the hydrofoil geometry on leading edge and other is rectangular grid which captures the trailing edge physics. C-mesh provides the advantage of fine grids in the higher resolution regions [9]. To obtain as many cells near the hydrofoil edge sizing is applied which results in more accurate computation in the region where the gradients are more pronounced which is basically captures the vortex generation. The transient simulation at Re no 99700 were performed with linear upwind FVM in Ansys Fluent using SIMPLE algorithm for velocity-pressure coupling [10, 11].
Fig. 1. NACA 4418 profile at ∝= 12°
Fig. 2. Structured C-mesh close to hydrofoil
3.2. Initial and boundary conditions
In order to simulate the motion of fluid from rest some initial value of free stream velocity (u0= 1 m/s) is given at the inlet boundary, and other boundary conditions used in Ansys Fluent are as follows:
Table 1. Boundary conditions at different locations
Velocity inlet
Pressure-outlet
Upper-wall
No-slip wall
Lower-wall
Once mesh was generated along with boundary conditions, the incompressible Navier-Stokes equations were discretized using Transition Shear Stress Transport (SST-4 equation) model and for pressure-velocity coupling SIMPLE method was used. One the velocity and pressure fields were computed the results were post-processed to compute the vorticity field as well as lift, drag, pressure and skin friction coefficients.
Computational flow dynamics (CFD) study has been carried out for wide range of flow regimes.
In this study main focus is the numerical transient simulations of 2D flow around NACA 4418 hydrofoil at 12° AOA. Uniform flow with free stream velocity if 1 m/s is used to start the simulation.
4.1. Vortex shedding and 2D instability
Even though most of real-life geometries are three-dimensional in nature but for good understanding of flow separation development, vortex shedding and instability 2D simulations still are considered to be helpful. The 2D simulation is initialized with uniform velocity at inlet with Re no 99700 for transient simulation.
The instantaneous spanwise contours of vorticity after simulation are shown in Fig. 3, where vortex shedding and flow separation can be seen clearly on the suction side of hydrofoil. The separation of flow that begins at the leading edge of the hydrofoil results in separate shear layer which becomes unstable and forms large scale vortices causing vortex-shedding. These vortices are carried to form vortex pair by the mean flow along downstream of hydrofoil surface which considers that vortices are developed due to streamwise growth of perturbation of separate shear layer. The flow near the wake contains strong shear layers due the two flow with opposite vorticity passing over two surfaces of hydrofoil. To understand the time dependency of vortex shedding for the cycle, contour for vortex shedding are simulated for a cycle of 10 seconds.
Fig. 3. Vortex shedding at different times (t= 2 sec, t= 4 sec, t= 6 sec, t= 8 sec, t= 10 sec, t= 11 sec)
The result of pressure distribution along the upper surface and lower surface of hydrofoil is shown in Fig. 4. Pressure coefficient simply represents the change in static pressure around the hydrofoil. The minimum pressure often occurs close to leading edge. Using Bernoulli's for incompressible flow we can say that with increase in local velocity, the pressure coefficient at that place decreases. According to certain flow velocity these pressure variation yields usable range of lift coefficients. In Fig. 5, the skin friction coefficient along the hydrofoil length is shown which is described as the ratio of local shear stress and characteristics dynamic pressure.
Fig. 4. Coefficient of pressure versus chord length
Fig. 5. Skin friction coefficient versus chord length
Fig. 6. Lift coefficient versus flow time
The value of lift coefficient for the time flow is reported in Fig. 6. From the transient computation, the instability occurs after few iterations and it converge to fully periodic flow with shedding of vortex structures.
At an angle of 12°, the vortex shedding becomes increasingly disorganized and this irregular shedding describes the periodicity of oscillatory forces. Fig. 7. shows the power spectral density function (PSD) of lift coefficients. We can observe the first peak value of PSD at frequency of 15 Hz. From the vibration viewpoint, the forcing frequency is important for prevention of resonance.
Fig. 7. Power spectral density of lift coefficient versus frequency normalized by the chord length
We simulated incompressible flow past a NACA 4418 hydrofoil at Reynolds Number of 99700, using the Transient SST (DES) model in conjunction with SIMPLE pressure-velocity coupling method. We have achieved significant savings in both memory usage and computation time by using proper numerical scheme.
In this study, the numerical simulation demonstrates the vortex shedding of a 2D hydrofoil at an angle of 12° with respect to sinusoidal motions of free stream flow. Magnitude of free stream velocity was kept constant. With two- dimensionality, it is possible to solve problem easily as 3D problems requires significant computational resources. We found in the study that the vortex formation in periodically varying inflows remains same, as certain frequency of free-stream oscillation tends to make vortex shedding more regular again. However, effect of cavitation on vortex shedding is not yet understood. Future work will include numerical simulation of 2D and 3D hydrofoil to understand the relationship between vortex shedding and cavitation.
Agromayor Roberto, Rúa Jairo, Kristoffersen Reidar Simulations of starting and stopping vortices of an Airfoil. Linköping Electronic Conference Proceedings, 2017, p. 66-75. [Publisher]
Balakumar P. Direct numerical simulation of flows over an NACA-0012 airfoil at low and moderate Reynolds numbers. 47th AIAA Fluid Dynamics Conference, Denver, Colorado, 2017. [Publisher]
White F. M. Fluid Mechanics. 8th Edition, McGraw-Hill, 2017. [Search CrossRef]
King Roger A review of vortex shedding research and its application. Ocean Engineering, Vol. 4, Issue 3, 1977, p. 141-171. [Publisher]
Versteeg H., Malalasekra W. An Introduction to Computational Fluid Dynamics. 2nd Edition, Pearson, 2018. [Search CrossRef]
Young D. L., Huang J. L., Eldho T. I. Simulation of laminar vortex shedding flow past cylinders using coupled BEM and FEM model. Computer Methods in Applied Mechanics and Engineering, Vol. 190, 2001, p. 5975-5998. [Publisher]
Zhai Zhiqiang, Zhang Zhao, Zhang Wei, Chen Qingyan Evaluation of various turbulence models in predicting airflow and turbulence in enclosed environments by CFD: part 1: summary of prevalent turbulence models. HVAC & R Research, Vol. 13, Issues 6, 2007, p. 853-870. [Publisher]
Saatchi D., Fathali M., Khojasteh A. R. The impacts of five different turbulence models on the accuracy of computational aeroacoustics results for an airfoil and acoustic localization analysis for well suited model. International Review of Mechanical Engineering (I.RE.M.E.), Vol. 8, Issue 2, 2014, p. 387-398. [Search CrossRef]
Ockfen Alex E., Matveev Konstantin I. Aerodynamics characteristics of NACA 4412 Airfoil section with flap in extreme ground effect. International Journal of Naval Architecture and Ocean Engineering, Vol. 1, Issue 1, 2009, p. 1-12. [Publisher]
Ausoni Philippe, Farhat Mohamed, Avellan Francois Hydrofoil roughness effects on von Karman vortex shedding. 2nd International Meeting of the Workgroup on Cavitation and Dynamic Problems in Hydraulic Machinery and Systems Timisoara, Romania, 2007. [Search CrossRef]
Yu An, Luo Xianwu, Ji Bin, Huang Renfanh Cavitation simulation with consideration of the viscous effect at large liquid temperature variation. Chinese Physics Letters, 2014. [Search CrossRef]
Shan Hua, Jiang Li, Liu Chaoqun Direct numerical simulation of flow separation around a NACA 0012 Airfoil. Computers and Fluids, Vol. 34, 2005, p. 1096-1114. [Publisher]
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text:
Q: java scp file to remote using ganymed-ssh2 I am having a situation here which I need to resolve. I have to upload particular elements of an xml file to upload it to a server, managed to do that, and I created a demo method to check if the file is being uploaded to the server or not.
My xml file has the structure,
<config>
 <engine>
    <eid>1</eid>
    <sometextelement>text</sometextelement>
 </engine>

 <engine>
    <eid>2</eid>
    <sometextelement>text</sometextelement>
 </engine>

 <engine>
    <eid>3</eid>
    <sometextelement>text</sometextelement>
 </engine>

</config>

and here is my servlet code:
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        doPost(request,response);
    }

    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        response.setContentType("application/json");
        //response.setHeader("Cache-Control", "no-cache");
         PrintWriter out = response.getWriter();
         JSONObject obj = new JSONObject();
         String value = request.getParameter("value");
            String message = "";
            String update = "";
            Element element = null;
            Element root = null;
            XMLOutputter xmlOutputter = new XMLOutputter();
        try{
        doc = saxBuilder.build("E:/workbench j2ee/cPEP_UI/WebContent/engine.xml");

        }catch(Exception e){
            e.printStackTrace();
        }
        root = doc.getRootElement();
        List list = doc.getRootElement().getChildren();
        Iterator itr = list.iterator();
        while(itr.hasNext()){
             element = (Element)itr.next();
            System.out.println("Entered 1");
          File f = File.createTempFile("engine_",".xml");
           System.out.println(f);
            xmlOutputter.output(element, new FileWriter(f));

            putFile(f);
        }

         // xmlOutputter.output(doc, new FileWriter("E:/workbench j2ee/cPEP_UI/WebContent/engine.xml"));

        // System.out.println("hello from system");
        // out.println("hello");

    }

    public void putFile(File f){
         System.out.println("File String: "+f.toString());
         Connection Conn = null;
          try {
           Conn = new Connection("ftp.someserver.co.uk",22);
           ConnectionInfo info = Conn.connect();
           Conn.authenticateWithPassword("webmaster@someserver.co.uk", "mypass");
           SCPClient SCP = new SCPClient(Conn);
           SCP.put(f.toString(), "/public_html/webmaster", "0755");
           Conn.close();
          } catch (Exception e) {
           try {
            Conn.close();
           } catch (Exception e1) {}
    }
    }

Now, From the above code I am getting file created for engine 1, engine 2 and engine 3, and thats what I wanted, but now I want it to upload to the server too. and the putFile code is not working at all. No error is being displayed too, pass and user name are all fine, and the server name too. The port is also perfect. Whats wrong then?
any ideas?
Edit- 1
Heres the error:
java.io.IOException: There was a problem while connecting to ftp.someserver.co.uk:22
    at ch.ethz.ssh2.Connection.connect(Connection.java:699)
    at ch.ethz.ssh2.Connection.connect(Connection.java:490)
    at Push_Individual_Engine.putFile(Push_Individual_Engine.java:106)
    at Push_Individual_Engine.doPost(Push_Individual_Engine.java:81)
    at Push_Individual_Engine.doGet(Push_Individual_Engine.java:47)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859)
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
    at java.lang.Thread.run(Thread.java:662)
Caused by: java.net.ConnectException: Connection timed out: connect
    at java.net.PlainSocketImpl.socketConnect(Native Method)
    at java.net.PlainSocketImpl.doConnect(PlainSocketImpl.java:333)
    at java.net.PlainSocketImpl.connectToAddress(PlainSocketImpl.java:195)
    at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:182)
    at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:366)
    at java.net.Socket.connect(Socket.java:529)
    at ch.ethz.ssh2.transport.TransportManager.establishConnection(TransportManager.java:340)
    at ch.ethz.ssh2.transport.TransportManager.initialize(TransportManager.java:448)
    at ch.ethz.ssh2.Connection.connect(Connection.java:643)
    ... 18 more

A: You need to set PasswordAuthentication = yes in sshd_config file of the remote machine.

A: The probable reason why no error is being displayed is that you are discarding Exceptions. You should expect to get "doesn't work, but no error is being displayed" problems if you discard Exceptions. Instead, you should probably print a stack trace in the catch blocks, like this:
e.printStackTrace();

or log the exception, or re-throw the exception. Those are the three standard choices.

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Leaves are the main photosynthetic organs in plants and thus they are eminently important for growth and biomass accumulation. Leaves develop from the flanks of shoot apical meristems and after an initial phase of cell proliferation and polarity establishment they enter expansion and maturation phases. Early leaf development involves a massive reprogramming of cellular and physiological characteristics and leads to the formation of chloroplasts from non-green proplastids. Chloroplast function is subsequently maintained for a significant time span during which leaves fix carbon dioxide (CO2) into metabolic intermediates, starch and transportable sugars to serve the growth of other organs with limited or no photosynthetic carbon fixation, including sink leaves, roots or developing flowers. Leaves, as all organs, undergo a process of aging which eventually leads to the execution of an ordered deterioration process – senescence – that normally starts at the leaf tip and progressively moves towards the leaf´s base. During senescence, cellular constituents are destructed and the resulting metabolic breakdown products are transported from the degrading leaf to newly developing organs including seeds. Thus, like photosynthesis itself, senescence supports whole-plant development. Although leaf development is genetically programmed, environmental parameters and abiotic stresses (e.g. drought) have a significant impact as well, and evidence shows that leaves of different ages can be differentially responsive to such stimuli. Reactive oxygen species (ROS) or stress hormones (e.g. ABA) may have important functions in this regard, and cross-talk with growth-regulating hormones such as auxin, gibberellins of brassinosteroids may occur. Transcription factors (TFs) are important regulatory proteins in all organisms and they have been demonstrated to play key roles in virtually all processes that govern leaf development and their responses to stress. However, despite tremendous progress made in the last decade, our understanding of the regulatory integration of TFs with cellular metabolism, signaling and control by epigenetic mechanisms during the different phases of leaf growth remains vague at best in the vast majority of cases. For example, target genes are only known for a relatively small number of TFs, and in only rare occasions have the dynamics of TF-target gene interactions been studied or a cellular resolution of such interactions been analyzed, often due to technical limitations.
This Research Topic is aimed at establishing a wide collection of articles that focus on the different aspects of leaf development, from primordium initiation to senescence, to highlight recent advances in the field. We welcome all types of articles (original research papers, hypotheses, opinions, reviews, modeling approaches, methods) that present new insights into the regulatory networks and cascades underlying leaf development. We are particularly interested in receiving contributions that address the systems integration of gene regulatory with metabolic and signaling networks and consider aspects of leaf aging as well as transients between different leaf growth phases, particularly under conditions of abiotic or nutrient stresses. Articles addressing organelle development and function changes during leaf formation, as well as interactions between them, should also contribute to the Research Topic. We wish to elicit contributions from researchers working on either, dicot or monocot species.


text:
Home » World News » Piers Morgan blasts 'utterly insane' remake of beloved children's show
Piers Morgan blasts 'utterly insane' remake of beloved children's show
March 9, 2020 World News
'I knew the woke brigade would come for the Wombles!': Piers Morgan blasts 'completely and utterly insane' remake of beloved children's show featuring new-look PC characters
Piers Morgan branded the remake of the 1970s television series 'utterly insane'
Good Morning Britain presenter lashed out at 'woke brigade' over new version
A major revamp of The Wombles is underway, in attempt to revise for a new era
But Marcus Robertson, son of the show's creator, criticised the major revamp
Mr Robertson, 64, previously said it is a 'fight for the soul' of the children's show
Piers Morgan has lashed out at the 'woke' remake of the 1970s television series The Wombles, branding it 'completely and utterly insane'.
A major revamp of the BBC children's show is underway, in an attempt to revise the series for a modern, politically correct era.
But Marcus Robertson, the son of Elisabeth Beresford, the show's creator, recently criticised the CGI remake, accusing it of holding his family 'hostage'.
The Good Morning Britain presenter, 54, reacted to Mr Robertson's comments, saying: 'I knew eventually that the woke brigade would come for The Wombles.
'When I was growing up I loved The Wombles. Bear in mind the wombles are fictitious creatures, they are not humans.'
Co-host Susannah Reid interjected: 'Can we not spoil it for the children watching?'
Piers continued: 'They are not humans, their faces are painted in you may see orange and grey and blah blah blah.
'The family of Elizabeth Beresford, who created The Wombles, have been surprised to put it mildly, annoyed to put it accurately, that apparently in a new CGI version of the revamped version, a new BBC remake of it, apparently they now have wombles with deliberately darker skin tones to reflect diversity.
'And as the family say wombles have grey fur – orangey grey faces, says Elizabeth's son – I don't believe in black or white wombles and neither did my mum.'
He added: 'Who is actually saying we need to have wombles with darker skin tones to reflect to hit any diversity quota?
'It is completely and utterly insane.'
Piers Morgan (centre), 54, lashed out at the 'woke' remake of the 1970s BBC television series The Wombles. He branded the revamp 'completely and utterly insane'
A major revamp of the BBC children's show is underway, in an attempt to revise the series for a modern, politically correct era. But it has received criticism from the son of the show's creator
The Wombles were originally created in a series of children's novels from 1968. They appeared in a highly successful TV show (pictured) in the UK in the 1970s
It follows Mr Robertson, 64, telling The Mail on Sunday: 'It's a fight for the soul of the Wombles, I feel we're being held hostage.
'We've never owned all the rights, but we've always had respect for the idea that the Wombles came from my mother's head. Now that's all gone.'
He added: 'As far as the family is concerned, it should be a very simple story for children to enjoy, with no hidden messages other than the one that has always been there – about looking after their surroundings. Wombles are not humans. Sometimes I think that's not understood.'
Lawyers for Craig Treharne, the British businessman who recently acquired control of the series' copyright, reportedly declined to comment in detail on Mr Robertson's claims, but said his views are 'not shared' by Wombles Copyright Holdings Limited or the Wombles.
The Wombles were originally created in a series of children's novels from 1968.
The furry characters were known for their litter picking and rubbish clearing, helping the environment by recycling in creative ways.
They appeared in a highly successful TV show in the UK in the 1970s – and even a chart-topping hit.
The author, Ms Beresford, passed away in 2010 at the age of 84.
Cuomo says Trump's proposed NY quarantine would mean civil war
Megan Fox celebrates being bisexual in sultry Pride selfie: 'Putting the B in #LGBTQIA'
Coronavirus lingers in the air of crowded places for hours, scientists say – The Sun
Book claims Prince Harry 'ditched old friend for criticising Meghan'
Coronavirus restrictions could last for TWO YEARS as pandemic strikes in waves, Germany warns – The Sun
Coronavirus vaccine trial in humans gets underway in UK
'utte, blasts, Morgan, Piers
Former newspaper editor urges people to sue China over coronavirus
Woman finds love after rare condition stopped her having sex for 12 years


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At The Barrier
Live music, reviews and opinion
The Jayhawks – XOXO: Album Review
By John Barlass on 6th July 2020 • ( Leave a comment )
XOXO is the 11th album from Minnesota's The Jayhawks, their first since 2018's Back Roads And Abandoned Motels. Musically diverse, well-crafted songs and quality production make this a must-listen.
Release Date: 10th July 2020
Label: Sham/Thirty Tigers
Formats: DL, CD, vinyl (incl coloured)
It's also their third since they took their mid-2000's well-documented hiatus. The band's current lineup is Gary Louris on guitars and mellotron, Karen Grotberg on keyboards, Marc Perlman on bass, guitars and harmonica and Tim O'Reagan on drums, percussion, guitars and sitar. The band members are all accomplished vocalists and this shows in the quality of the lead and backing vocals that are a notable feature of this collection. Indeed, XOXO is notable for being the first Jayhawks album on which lead vocal (and also songwriting) contributions are split amongst all four members, rather than resting in the capable arms of mainstay Gary Louris.
Musically, XOXO is a diverse album. As would be expected, there are lashings of Alt-Country and sprinklings of rootsy Americana, but listen harder and you'll hear liberal servings of '60s British Invasion pop, traces of psychedelia and the occasional lump of jangly indie-rock. It really is a tasty mixture, all seasoned with detectable influences from The Eagles, The Byrds, Fleetwood Mac, Gene Clark (whose spirit seems to pervade the album) and even Elvis Costello. The album was recorded during live-in sessions at Pachyderm Studios in Cannon Falls, Minnesota, and the cohesive benefits of that arrangement are evident throughout.
The Alt-Country scene is set by This Forgotten Town, the album's opening cut. A muddy river, desert desolation and a shot preacher lead to salvation at the hands of a gentle female vision in a story related in Gary's best Gene Clark voice. Tim's Dogtown Days is a rootsy rocker with some tasty, echo-laden guitar at its heart and on Ruby, Karen gives the first of her shiver-inducing vocal performances, with assistance from guest Eric Heywood's soaring pedal steel. The strummed acoustic guitar intro to Homecoming develops into a 1960s pastiche which manages to, at the same time, deliver a chilling message about climate change and its environmental impact, before we move on to Society Pages in which Tim aims alternately mocking and dismissive jibes at those who court publicity for its own sake.
For the Louris/O'Reagan/Grotberg co-write, Bitter Pill, the ghost of Gene Clark makes a reappearance, this time with the aid of some beautiful guitar licks from another guest, Stephen McCarthy. Across My Field is Karen's second turn in the spotlight, which she outshines with some delicious vocal and piano and which Eric Heywood nearly steals with the best pedal steel performance on the album.
As we navigate towards the album's close, Marc Perlman takes a turn at the wheel with Down To The Farm, a whimsical song with strummed acoustic guitar backing and harmonised vocals that, once again, recall the best of 1960s Brit Pop – maybe Peter and Gordon. Album closer, Looking Up Your Number is another of Tim's songs, this time with soft, acoustic instrumentation.
For me, the album's standout tracks are Living in A Bubble, Gary's critique of the ratings-driven news cycle that predominates particularly (although not exclusively) in the US. Little Victories, a swampy, sinister song that compares favourably with Fleetwood Mac at their very best, and Illuminate, is an abstract, psychedelic, word laden piece that carries the listener back to 1967 and Knole Park, Sevenoaks (scene of The Beatles' Strawberry Fields video.) Living In A Bubble is tuneful and enjoyable, with hints of The Eagles' Hotel California and Illuminate is an abstract poke at the blatant narcissism of a certain public figure.
A review of XOXO would be incomplete without giving a mention to the three bonus tracks (which I assume are available only with the digital versions of the package). And Then You Walked Away, Hypocrite's Lament and particularly Karen's Jewel Of The Trianbelle are all excellent songs, worthy of inclusion in the main running order. Arguably, Jewel… is the best of Karen's three lead contributions to the album. Her vocals and piano work are outstanding and the song's tune and lyrics prompt comparisons to the work of Christine McVie or Sandy Denny.
XOXO is an excellent, diverse album from a group of highly talented, versatile musicians. The songs are well-crafted and the production is top-notch. This one is highly recommended, whether you're a Jayhawks die-hard, an Alt-Country dabbler or just merely curious.
Listen to This Forgotten Town here:
The Jayhawks online: Website / Facebook / Twitter / Instagram / YouTube
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Categories: Album Review, Featured
Tagged as: 10.07.20, Album Review, Gary Louris, The Jayhawks, Thirty Tigers, XOXO
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Published by John Barlass
John has been a music obsessive since he first heard 'Love Me Do' seeping out of the family radio in 1962. he spent a career in the rail industry before turning back to his first love of music. He plays bass guitar and melodeon, loves folk/rock and lives in Warwick.	View all posts by John Barlass
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text:
Walter James (SOS Femme en Danger – SOSFED): Walter graduated in 2006 from the University of Minnesota. Following college, he worked on international development in Haiti and Senegal, and studied human rights and international development in Senegal, Costa Rica, and Morocco. Walter first visited Eastern Congo as a 2009 Peace Fellow for The Advocacy Project, where he documented the work of civil society organizations such as SOS Femmes en Danger, Arche d'Alliance, and Tunza Mazingira. The following year, he graduated from the University of Maryland School of Public Policy with a Master's degree in Public Policy.
Happy Independence Day! Today, on June 30th, Congo is celebrating 51 years of independence from Belgium. In light of this national holiday, I thought I'd write up a little history of the African territory today known as the Democratic Republic of Congo, particularly its political history and how it relates to the state of the Kivus today.
At the Berlin Conference, King Leopold II of Belgium consolidates control over a massive chunk of central Africa. The Congo Free State, as the colony is known, is created ostensibly to encourage free trade and wipe out slavery. However, the true goal of the colony was for the personal profit of the king, who quite literally owned the colony all to himself. Tribes were given quotas of ivory, rubber, and other natural resources; the quotas were enforced through a brutal system of executions, floggings, and torture. It is estimated that anywhere from 10 to 13 million people were killed or forced to flee during the period of Belgian colonization.
On June 30, Congo declares itself independent from Belgian rule, creating the Republic of Congo. Leading the fledgling government is President Joseph Kasavubu, charismatic Prime Minister Patrice Lumumba, and army chief of staff Joseph Désiré Mobutu. Almost immediately, the mineral-rich provinces of Katanga and Kasai secede. When Lumumba turns to the Soviets to quell the rebellion to the disagreement of Kasavubu, Mobutu seizes control of the government from both politicians on September 14th. Lumumba is subsequently imprisoned. It is probable that the CIA was involved in Mobutu's "peaceful revolution", as Washington cables from mid-1960 indicate approval for CIA agents in Kinshasa for an operation "replacing Lumumba with a pro-Western group".
Patrice Lumumba is taken to Katanga and executed, with Belgian collaboration.
Joseph Désiré Mobutu mounts a coup and becomes the supreme leader of the Congo, declaring a one-party state.
Mobutu renames the country "Zaire" in a campaign of "authenticity" to diminish the colonial legacy hanging over the country. He also encourages Zairian citizens to drop European names, dress, and customs and adopt more African traditions; Mobutu himself adopts the name Mobutu Sese Seko.
Mobutu confiscates all foreign-owned enterprises (farms, plantations, industries, commercial enterprises) and turns them over to himself and the Zairian elite, who subsequently loot these enterprises to support lives of exorbitant luxury. The Zairian economy, which beforehand was experiencing on average 7 percent growth per annum, begins to rapidly decline.
Mobutu bows to international and domestic pressure and ends the one-party system in Zaire. However, despite having driven the country into massive poverty with his lavish lifestyle, Mobutu manages to stay in power through masterful manipulation of opposition forces.
Thousands of Hutu refugees flee to Zaire in wake of the Rwandan genocide and the victory of the RPF. Among the refugees are the remnants of the Interahamwe, the Hutu militia that performed much of the genocide, and also Hutu elements of the military that assisted in the genocide. Mobutu plays a tug-of-war with the refugee situation, welcoming the exiled génocidaires. International organizations (such as UNHCR) rush to provide assistance in the refugee camps, but do nothing to suppress extremist elements in the camps or move them farther away from the Rwandan border.
Rwanda invades Zaire, in order to hunt the exiled génocidaires rebuilding their forces in refugee camps just across the border. In the process, thousands of refugees are killed and the génocidaires flee further into the Zairian interior. The AFDL (Alliance des Forces Democratiques pour la Liberation), a coalition of 4 rebel groups in eastern Congo, forms and challenges Mobutu's government in Kinshasa. Laurent-Desire Kabila, an old foe of Mobutu's, emerges as the leader of the rebellion.
The AFDL, with support from several African governments, routes the Zairian army and marches triumphantly on Kinshasa on May 17. Mobutu, already ailing from prostate cancer, flees to Morocco in exile and dies several months later. Kabila is sworn in as president, and the country is renamed the Democratic Republic of Congo.
Conflict continues in eastern Congo as ethnic tensions boil to a head, with fighting between the escaped Hutu extremists, the new Congolese military (made up largely of Kabila's former rebel force), Burundian FDD rebels, Rwandan troops, Ugandan troops, and the Mai Mai (grassroots militia resenting any Rwandophone ethnic groups in the region). Kabila starts to lose the support of crucial allies with his erratic behavior. In 1998, Kabila orders all Rwandan troops to leave the Congo; very soon afterward, a new rebel movement, the RCD (Rassemblée Congolaise pour la Démocratie) forms in the east to challenge Kabila's authority, again with backing from several African governments. Only an intervention from Angola and Zimbabwe prevents the rebel movement from duplicating Kabila's own victorious march on Kinshasa. Despite failing to secure Kinshasa, RCD still controls much of eastern Congo. The warfare between the different armed factions continues to toll heavily upon the civilian population, with massacres being committed by troops from all sides.
The first observers from MONUC (Mission de l'Organisation des Nations Unies au Congo) arrive in the Congo
Laurent-Desire Kabila is assassinated by one of his own ex-child soldiers. His son, Joseph Kabila, succeeds his father as President of the DR Congo. Kabila fils immediately starts courting international support in order to de-legitimize the various rebel factions laying claim to the Congo.
Kabila fils signs power-sharing agreements with the MLC (Mouvement pour la Libération du Congo) and the RCD, the two most formidable rebel groups in the Congo. Rwanda begins to withdraw troops from eastern Congo.
In its first-ever national election, the DR Congo elects Joseph Kabila as president. Running against Kabila is Jean-Pierre Bemba, leader of the MLC. Today, Bemba is imprisoned at The Hague on trial for war crimes.
Laurent Nkunda, a former FAC/RCD commander, forms a new rebel faction, the CNDP (Congres National pour la Défense du Peuple), in North Kivu. The CNDP gains much ground in the Kivus and ignites more conflict, but eventually the movement is subdued through political negotiations with the Rwandan government. Nkunda is taken prisoner by Rwanda, and the CNDP units integrate into the FARDC.
The FARDC (Forces Armees de la Republique du Congo) carry out Operation Kimia II in eastern Congo. The goal of Kimia II was to wipe out the FDLR and other armed groups operating outside of state authority. The FDLR sustains heavy losses and is forced farther into the interior, but civilians pay a heavy toll in human rights abuses committed by members of all armed groups involved.
The FARDC carries out Operation Amani Leo in eastern Congo, an effort to further dislodge the FDLR and other rebel groups in eastern Congo.
Congo's second national election is scheduled for this fall.
So, what is going on in Uvira today? Well, people tell me there used to be a parade, but there isn't one this year. President Kabila is in Lubumbashi for a large military parade, and it is being broadcasted all across the country; I watched some of it this morning at the little boutique where I buy bread. However, there is sure to be a big party tonight. When I was walking past the Esperanza (a popular local restaurant), a group of men were unloading case after case of beer from a car with Burundian plates. A large banner on the wall proclaimed a big June 30 party at the Esperanza tonight, if you are willing to fork over the hefty $5 entry fee.
Fortunately, the streets are quiet. With the upcoming elections, many people are worrying about political demonstrations that may turn violent, but in the past week or so there haven't been any major manifestations in Uvira.
Let the festivities begin!
Congolese woman in Baraka preparing chapati
Posted By WALTER JAMES
Nice history lesson!
About to break open "The African Stakes of the Congo War."


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The Database Of All The Reviews
Eli Whitney and the Cotton Gin
Jessica Gunderson
Illustrated by Gerry Acerno, Rodney Ramos, and Charles Barnett III
Non-Fiction (Series)
Capstone Press, 2007, 0-7368-6843-7
For farmers in the southern states in America, cotton was their biggest crop. They had slaves to plant, tend, and harvest the cotton, but it took a lot of work, and time, to remove all the seeds from the cotton. At first the farmers had to sell their cotton to English mills because America had no mills. But then, in 1793, the first American cotton mill opened. Though the mill was a success, getting enough cotton to meet demand was hard because it took so long to clean the cotton.
Eli Whitney was working as a tutor in the south when he was told about this problem. Being skilled with his hands Eli decided to see if he could invent a machine that would remove the seeds from the cotton. After talking to the local farmers and the pickers, Eli set to work. After building several prototypes, and after solving the problems he encountered, Eli finally had a machine that worked.
In this book a well written text is combined with graphic novel type artwork. The result is a story that is interesting, informative, and easy to read. This, and the other books in this series, will show young readers that history and biographies can be entertaining, and the books can give children a deeper appreciation for the world around them.


text:
nature structural & molecular biology
Solid-state NMR structure of a pathogenic fibril of full-length human α-synuclein
Marcus D Tuttle1 nAff11,
Gemma Comellas2,
Andrew J Nieuwkoop1 nAff11,
Dustin J Covell3,4,5,
Deborah A Berthold1,
Kathryn D Kloepper1 nAff11,
Joseph M Courtney1,
Jae K Kim1,
Alexander M Barclay2,
Amy Kendall6,7,
William Wan6,7 nAff11,
Gerald Stubbs6,7,
Charles D Schwieters8,
Virginia M Y Lee3,4,5,
Julia M George9 &
Chad M Rienstra1,2,10
Nature Structural & Molecular Biology volume 23, pages 409–415 (2016)Cite this article
Solid-state NMR
Supramolecular assembly
Misfolded α-synuclein amyloid fibrils are the principal components of Lewy bodies and neurites, hallmarks of Parkinson's disease (PD). We present a high-resolution structure of an α-synuclein fibril, in a form that induces robust pathology in primary neuronal culture, determined by solid-state NMR spectroscopy and validated by EM and X-ray fiber diffraction. Over 200 unique long-range distance restraints define a consensus structure with common amyloid features including parallel, in-register β-sheets and hydrophobic-core residues, and with substantial complexity arising from diverse structural features including an intermolecular salt bridge, a glutamine ladder, close backbone interactions involving small residues, and several steric zippers stabilizing a new orthogonal Greek-key topology. These characteristics contribute to the robust propagation of this fibril form, as supported by the structural similarity of early-onset-PD mutants. The structure provides a framework for understanding the interactions of α-synuclein with other proteins and small molecules, to aid in PD diagnosis and treatment.
Cell-free synthesis of amyloid fibrils with infectious properties and amenable to sub-milligram magic-angle spinning NMR analysis
Alons Lends
, Asen Daskalov
… Antoine Loquet
Opportunities and challenges of alpha-synuclein as a potential biomarker for Parkinson's disease and other synucleinopathies
Pedro Magalhães
& Hilal A. Lashuel
npj Parkinson's Disease Open Access 22 July 2022
Cryo-EM structures of prion protein filaments from Gerstmann–Sträussler–Scheinker disease
Grace I. Hallinan
, Kadir A. Ozcan
… Ruben Vidal
Acta Neuropathologica Open Access 12 July 2022
Figure 1: Effects of preformed α-syn fibril samples on neurons.
Figure 2: Long-range SSNMR structural restraints for an α-syn fibril.
Figure 3: Three-dimensional structure of an α-syn fibril.
Figure 4: Validation of α-syn fibril structure by microscopy and fiber diffraction.
Biological Magnetic Resonance Data Bank
Protein Data Bank
2N0A
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This study was supported by the US National Institutes of Health (NIH) (grants R01-GM073770 to C.M.R., P50-NS053488 to V.M.Y.L. and P01-AG002132 to G.S.) and used SSNMR instrumentation procured with the support of grant S10-RR025037 (to C.M.R.) from the NIH National Center for Research Resources (NCRR). M.D.T., A.J.N. and A.M.B. were supported as members of the NIH Molecular Biophysics Training Grant at the University of Illinois at Urbana-Champaign (T32-GM008276), and D.J.C. is supported by grant T32-AG000255. J.M.C. was supported by a US National Science Foundation Graduate Research Fellowship. C.D.S. is supported by the Intramural Research Program of the Center for Information Technology at NIH. The authors thank J. Wall and B. Lin (Brookhaven National Laboratory) for STEM MPL sample preparation and data collection. The Brookhaven National Laboratory STEM was an NIH-supported Resource Center (P41-EB2181), and additional support was provided by the US Department of Energy (DOE), Office of Biological and Environmental Research. TEM images were collected at the Frederick Seitz Materials Research Laboratory Central Facilities, University of Illinois, which are partially supported by the DOE under grants DE-FG02-07ER46453 and DE-FG02-07ER46471. The Voyager-DE STR MALDI TOF mass spectrometer was purchased in part with a grant from the NIH NCRR (S10-RR011966). The Stanford Synchrotron Radiation Lightsource (SSRL) is a national user facility operated by Stanford University on behalf of the DOE, Office of Basic Energy Sciences. The SSRL Structural Molecular Biology Program is supported by the DOE and the NIH. The authors thank M. Tang (College of Staten Island) for helpful discussions.
Marcus D Tuttle, Andrew J Nieuwkoop, Kathryn D Kloepper & William Wan
Present address: Present addresses: Department of Chemistry, Yale University, New Haven, Connecticut, USA (M.D.T.), Leibniz-Institut Für Molekulare Pharmakologie, Berlin, Germany (A.J.N.), Department of Chemistry, Mercer University, Macon, Georgia, USA (K.D.K.) and Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany (W.W.).,
Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
Marcus D Tuttle, Andrew J Nieuwkoop, Deborah A Berthold, Kathryn D Kloepper, Joseph M Courtney, Jae K Kim & Chad M Rienstra
Center for Biophysics and Quantitative Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
Gemma Comellas, Alexander M Barclay & Chad M Rienstra
Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
Dustin J Covell & Virginia M Y Lee
Institute on Aging, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
Center for Neurodegenerative Disease Research, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
Amy Kendall, William Wan & Gerald Stubbs
Center for Structural Biology, Vanderbilt University, Nashville, Tennessee, USA
Division of Computational Bioscience, Center for Information Technology, National Institutes of Health, Bethesda, Maryland, USA
Charles D Schwieters
Department of Biological and Experimental Psychology, School of Biological and Chemical Sciences, Queen Mary University of London, London, UK
Julia M George
Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
Chad M Rienstra
Marcus D Tuttle
Gemma Comellas
Andrew J Nieuwkoop
Dustin J Covell
Deborah A Berthold
Kathryn D Kloepper
Joseph M Courtney
Jae K Kim
Alexander M Barclay
Amy Kendall
William Wan
Gerald Stubbs
Virginia M Y Lee
M.D.T. analyzed and collected SSNMR data, performed structure calculations, analyzed structural features and was the primary author on the manuscript. G.C. analyzed and collected SSNMR data, performed MPL data analysis and provided input on the manuscript. A.J.N. analyzed and collected SSNMR data, performed initial structure calculations and provided input on the manuscript. D.J.C. performed the immunofluorescence, biochemical and biophysical assays and helped prepare the manuscript. D.A.B. prepared isotopically labeled samples and provided input on the manuscript. K.D.K. aided in sample preparation and manuscript preparation. J.M.C. created scripts for data conversion, performed analysis of final structures and provided input on the manuscript. J.K.K. contributed to the sample preparation methods. A.M.B. contributed to the mass spectrometry and solution NMR data and analysis. A.K. and W.W. prepared fiber diffraction samples and collected and analyzed fiber diffraction data. G.S. analyzed fiber diffraction data and aided in manuscript preparation. C.D.S. supported the development of structure calculations in XPLOR-NIH. V.M.Y.L., J.M.G. and C.M.R. were the primary investigators, designed the experiments and aided in manuscript preparation, data collection and interpretation.
Correspondence to Chad M Rienstra.
Integrated supplementary information
Supplementary Figure 1 Mass spectrometry and solution NMR data for α-syn samples used in this study.
(a) Matrix-assisted laser-desorption and ionization time-of-flight (MALDI-TOF) mass spectrum of uniformly-13C,15N-enriched α-syn monomer (blue) and natural abundance monomer (red). The molecular mass of natural abundance α-syn monomer was calculated to be 14.46 kDa, in agreement with the experimental mass spectrum. The mass of 15.24 kDa for the U-13C,15N-labeled sample corresponded to a ~98% incorporation of 13C and 15N during protein expression. (b) 15N-1H HSQC spectrum of monomeric α-syn prior to fibrillization. The chemical shifts agreed well with the published assignments (Eliezer, D., Kutluay, E., Bussell, R. & Browne, G. Conformational properties of α-synuclein in its free and lipid-associated states. J. Mol. Biol. 307, 1061–1073 (2001).)
Supplementary Figure 2 SSNMR spectroscopy data for α-syn fibrils, exhibiting cross-peaks indicative of long-range restraints and intermolecular registry of the fibrils.
(a) 2D 13C-13C SSNMR {1H}-13C-{1H-1H}-13C spectrum (Lange, A., Luca, S. & Baldus, M. Structural constraints from proton-mediated rare-spin correlation spectroscopy in rotating solids. J. Am. Chem. Soc. 124, 9704–9705 (2002).) of dilute α-syn fibrils (sample D from Table 1) showing unambiguous, long-range intramolecular correlations. Data were acquired at 750 MHz 1H frequency, 12.5 kHz MAS and 400 μs 1H-1H mixing time, with 12 days signal averaging. Red labels correspond to unambiguous long-range distances, including those from A78 to V48, from A69 to G93, from F94 to I88, and from V82 to A89. These intramolecular long-range restraints were inconsistent with structural models that exhibit a domain swap. (b-e) 2D 15N,13C SSNMR transferred echo double resonance (TEDOR, Jaroniec, C.P., Filip, C. & Griffin, R.G. 3D TEDOR NMR experiments for the simultaneous measurement of multiple carbon-nitrogen distances in uniformly 13C, 15N-labeled solids. J. Am. Chem. Soc. 124, 10728–10742 (2002).) data showing intermolecular interactions. The data were collected for four samples: (b) 1,3-13C glycerol,15N-labeled fibrils (sample B), signal averaged for 28 hr; (c) 50:50 [1,3-13C]glycerol, natural abundance (n.a.) nitrogen: n.a. carbon, 15N labeled (sample E), signal averaged for 81 hr; (d) [2-13C]glycerol,15N labeled (sample C), signal averaged for 113 hr; and (e) 50:50 2-13C glycerol, n.a. nitrogen: n.a. carbon, 15N labeled (sample F), signal averaged for 124 hr. Data was collected with mixing times of (c, e) 14.4 ms at 500 MHz 1H frequency, 11.1 kHz MAS, and (b, d) 16.0 ms at 600 MHz 1H frequency, 10.0 kHz MAS. Cross-peaks present in both parts b and c, or d and e, demonstrate a parallel, in-register arrangement (Debelouchina, G.T., Platt, G.W., Bayro, M.J., Radford, S.E. & Griffin, R.G. Intermolecular alignment in β2-microglobulin amyloid fibrils. J. Am. Chem. Soc. 132, 17077–17079 (2010).) (f–k) Spectra of sample B collected at 750 MHz 1H frequency, 12.5 kHz MAS (f-i) 2D 13C-13C spectra using dipolar-assisted rotational resonance (DARR, Takegoshi, K., Nakamura, S. & Terao, T. 13C-1H dipolar-assisted rotational resonance in magic-angle spinning NMR. Chem. Phys. Lett. 344, 631–637 (2001).) mixing times of (f) 50 ms, signal averaged for 10.9 hr, (g) 100 ms, signal averaged for 5.7 hr, (h) 200 ms, signal averaged for 12.0 hr, and (i) 300 ms, signal averaged for 12.7 hr. Several long-range correlations (red) were observed between the F94 aromatic ring resonances (CD and CE) and I88, A90 and A91. (j-k) 2D planes from a 3D 15N-13CO-13CX correlation spectrum signal averaged for 24 hr. Long-range correlations observed at this relatively short mixing time indicate internuclear distances <5 Å.
Supplementary Figure 3 Full-length structure of the α-syn fibril, illustrating important features in expanded regions.
(a) View along the fibril axis showing the highly ordered core and the disordered tails. (b) Side view showing the β-sheet packing between each monomer as well as the disordered tails. (c-f) Core interactions illustrating NMR distance restraints with dotted lines. (g-l) Backbone traces for neighboring monomers drawn in blue, yellow, orange and red. (g, h) Side and top views of the salt bridge from E46 to K80 of the neighboring monomer. (i, j) Side and top views of the I88-A91-F94 pocket perpendicular to the fibril axis, exhibiting short intermolecular distances. (k, l) Side and top view of the Q79 side chain exhibiting a glutamine ladder, with intermolecular hydrogen bonds involving Nɛ2 and Oɛ1 moieties.
Supplementary Figure 4 SSNMR internal validation of structural restraints and dihedral angles for the α-syn fibril structure.
(a) The backbone trace is shown in grey, and black lines represent unambiguous distance restraints. Blue lines correspond to the shortest observed distance among the possible ambiguous assignments. The resulting structure is the lowest energy conformer consistent with all of the data. (b-c) Ramachandran probability maps of accepted dihedral angle regions (Lovell, S.C. et al. Structure validation by Cα geometry: φ,ψ and Cβ deviation. Proteins 50, 437–450 (2003).) and plotted in Chimera (Pettersen, E.F. et al. UCSF Chimera—a visualization system for exploratory research and analysis. J. Comput. Chem. 25, 1605–1612 (2004).) for residues 41–100. The only residue not in the accepted range is E57, which is part of an unstructured loop and lacks NMR restraints in the simulated annealing calculations. All glycine residues are within the accepted Ramachandran space.
Supplementary Figure 5 Cross-validation of the SSNMR structure of α-syn fibrils with electron microscopy and X-ray fiber diffraction.
(a) Chemical shift comparison of the fibril sample for solid-state NMR before and after washing with 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) buffer and sonication for electron microscopy. (b) Expansions of overlaid 2D 13C-13C spectra of the U-13C, 15N α-syn fibril as prepared for solid-state NMR (red) and fibrils washed with HEPES buffer as the samples for electron microscopy (blue). Spectra were acquired at 600 MHz 1H frequency, 13.3 kHz magic-angle spinning (MAS) and 50 ms dipolar-assisted rotational resonance (DARR, Takegoshi, K., Nakamura, S. & Terao, T. 13C-1H dipolar-assisted rotational resonance in magic-angle spinning NMR. Chem. Phys. Lett. 344, 631–637 (2001).). (c) Equatorial intensity plot of the calculated and experimental fiber diffraction pattern of the α-syn fibril. The solid line shows the experimental fiber diffraction pattern (equatorial intensity projected from Figure 4c) compared to the simulated pattern (dotted line) from the atomic coordinates of the structure presented in Figure 3. The simulated pattern recapitulates the main features of the experimental pattern including the fine features near 0.12 Å−1. The correlation coefficient between the two patterns is 0.77, in good agreement with previous amyloid fibril fiber diffraction comparisons.
Supplementary Figure 6 Comparison of the Cα chemical-shift perturbations for three early-onset Parkinson's disease–mutant forms of α-syn, relative to the wild-type chemical shifts.
(a–c) Chemical shift perturbation plots of the absolute deviation of the Cα shifts for A30P, E46K, and A53T previously published (Lemkau, L.R. et al. Mutant protein A30P α-synuclein adopts wild-type fibril structure, despite slower fibrillation kinetics. J. Biol. Chem. 287, 11526-11532 (2012); Lemkau, L.R. et al. Site-specific perturbations of α-synuclein fibril structure by the Parkinson's disease associated mutations A53T and E46K. PLoS One 8, e49750 (2013).) relative to the wild-type chemical shifts used in this work.
Supplementary Figures 1–6 and Supplementary Table 1 (PDF 3466 kb)
Tuttle, M., Comellas, G., Nieuwkoop, A. et al. Solid-state NMR structure of a pathogenic fibril of full-length human α-synuclein. Nat Struct Mol Biol 23, 409–415 (2016). https://doi.org/10.1038/nsmb.3194
Issue Date: May 2016
DOI: https://doi.org/10.1038/nsmb.3194
Asen Daskalov
Antoine Loquet
Conformational strains of pathogenic amyloid proteins in neurodegenerative diseases
Dan Li
Cong Liu
Nature Reviews Neuroscience (2022)
The C-terminal tail of α-synuclein protects against aggregate replication but is critical for oligomerization
Azad Farzadfard
Jannik Nedergaard Pedersen
Daniel Erik Otzen
Hilal A. Lashuel
npj Parkinson's Disease (2022)
Kadir A. Ozcan
Ruben Vidal
Acta Neuropathologica (2022)
α-synuclein folds: the cards are on the table
Wouter Peelaerts
Veerle Baekelandt
Nature Structural & Molecular Biology News & Views 04 May 2016
Nature Structural & Molecular Biology (Nat Struct Mol Biol) ISSN 1545-9985 (online) ISSN 1545-9993 (print)


text:
New Streaming Service CÜR Hires Jim Urie as President, CEO
Jim Urie, the former head of Universal Music Group Distribution, has joined CÜR Media, a new digital music service, as executive chairman of the company's board of directors and interim president/CEO.
"CÜR is a next generation music streaming service with the lowest price in the industry at $1.99 per month, properly compensating artists and providing new opportunities for the music industry," CÜR Media Founder Tom Brophy says in a statement on the news. The company describes itself as a next-generation social music experience, with plans to launch social music applications for mobile and web.
According to its website, the company began testing the service in early 2012 as Radiate, but took the product offline to enhance the platform.
In 2014, the company went public through the over-the-counter Bulletin Board and raised $9.6 million through a private placement. In 2015, it received a futher $3.2 million by allowing warrant holders to buy shares at a discounted price. Last month it drew $2 million in venture capital financing, led by Intuitive Venture Partners and Katalyst Securities.
While Urie replaces Brophy as interim chief, the announcement says the company is actively looking for a permanent president and CEO. Brophy will continue to have an active role in the company and will continue to be a member of the board of directors.
Urie led Universal Music Group's distribution arm for almost 16 years, initially being brought in as the heir apparent to its then-head, Henry Droz. During his time at Universal, he helped bring several key independent labels like Concord and Big Machine under the Universal umbrella, as well as starting Fontana, which was merged into INgrooves.
"There is a tremendous opportunity to break new ground in the music streaming space, and I believe the CÜR Music offering is poised to do just that," Urie said in a statement. "Upon launch, we will be the first streaming service that brings new price points to the market and exciting ways for our customers to interact socially. I look forward to bringing this dynamic product to market."
CUR Music SreamingJim UriePresident and CEO
Meet: The Aston Grey Project
Rihanna Launches Global Scholarship Program
Cayman Kelly Releases New Autobiographical Book
WKYS-DC names Joshua "J1" Raiford PD


text:
Антюнья́к () — коммуна во Франции, находится в регионе Лангедок — Руссильон. Департамент коммуны — Од. Входит в состав кантона Куиза. Округ коммуны — Лиму.

Код INSEE коммуны — 11010.

Население
Население коммуны на 2008 год составляло 324 человека.

Экономика
В 2007 году среди 193 человек в трудоспособном возрасте (15—64 лет) 130 были экономически активными, 63 — неактивными (показатель активности — 67,4 %, в 1999 году было 60,8 %). Из 130 активных работали 105 человек (60 мужчин и 45 женщин), безработных было 25 (11 мужчин и 14 женщин). Среди 63 неактивных 14 человек были учениками или студентами, 32 — пенсионерами, 17 были неактивными по другим причинам.

См. также
 Список округов Франции

Примечания

Ссылки

Коммуны департамента Од

redpajama_set_name: RedPajamaWikipedia


It was believed, in the not too distant past, that we could not change our brains once they were fully developed. That in our mid-twenties, when our brains are more or less fully formed, we're stuck with it. What you've got is what you've got, essentially, and that your particular twenty-something brain, with its existing neuro-pathways, configurations and functioning, is what you're stuck with for the remainder or your long life. The scientific community told us so and we accepted this static view of our neuro-make-up.
I met Sarah and James Roy as they were traveling through Costa Rica searching for a new home for their Neuro-Feedback/Yoga Transformational Retreats. I spent an intriguing evening with these two compassionately knowledgeable visionaries, geeking out on the brain and our ability to, literally, change our minds.
I was aware of "neuro-plasticity," the malleability of our brains and their ability to actually re-configure our wiring, if you will, and teach ourselves new ways of thinking and being. I had also learned about "neuron-genesis," the process of "birthing" new neurons throughout our lifetime by engaging in things like exercise, proper sleep health and nutrition, novelty and learning new things. Our brain's plasticity, ability to change, has long been recognized now and exulted in celebratory fashion.
We really can change our minds, thus changing our lives.
What tripped my trigger the most was the therapy that Brainworks, Sarah & James' London-based organization, is offering. They are helping people change and improve the quality of their lives significantly and with evidence/research-based, long-term results.
But that's not all. They are helping people to stop suffering from their own mis-perceived thinking, over-active and anxious nervous systems, correcting and eliminating disorders like autism, bi-polar and asperger and they are doing it alongside yoga and nutrition. They were speaking my language!
Getting to know Sarah over the past two years as one of my yoga students, I expressed a desire to learn more. "I want to see your brain!" Sara said one day after yoga class. So I popped over for a visit, they hooked me up and scanned my brain. Talk about exposed!
It didn't hurt, was non-intrusive and gave me a glimmer of insight into the daily residence of Heidi-mind. Hmmmmm. I wanted more.
Thus we put our brilliant brains together and came up with a plan. I would spend one week assisting at one of their Costa Rican Transformational Retreats in exchange for a series of neuro-feedback therapy sessions. Okay!
I was wide open and curious.
Anything I can do to be a better, more peaceful version of myself, a more knowledgeable teacher and healthier human being, I'm down for. Count me in.
Read my daily journal entries below from a 7-day retreat in Costa Rica for some raw and vulnerable details about my unbeknownst depression and way out of it.
Arrived after 1 month of traveling and transition from the U.S. to my Costa Rican winter home. Exhausted & ungrounded from the flurries of movement, having daily hot flashes (can't believe I'm starting peri-menopause at 43!) and overwhelmed by some challenges at work. Grateful to have landed in this gorgeous resort with dear friends. Nervous & curious about what's to come.
I'm helping Sarah in the kitchen this week. She's taken on meal prep for the group (quite courageous). I'm "shadowing" Kate Hewett, the yoga instructor, and will have 3 brain sessions this week. Sarah says we'll do about 12 over the next month since I live here and we don't want to overwhelm my brain with more than the usual 6 sessions in one week. I'm still working this week, need to be online and manage Selva. The others are taking a total break from work & technology. 90% organic meals, daily yoga, more.....tired. Must rest. 9:10pm. This is gonna be goooooood!
"We don't see personality in brainwaves, only what is obstructing perception."
6:30am yoga with Kate. She's quite an experienced and competent teacher, taking it slow & easy, introducing people to yoga. Feeling reserved and unsure in this small crowd of mostly foreigners. Am I a teacher? Am I kitchen staff? Am I a workshop participant? What is my role? Sarah says this is the "self-critic" talking. She's seen my brain (more on that later), she would know. Relaxing into what is and letting myself be quiet.
The ideal brain is flexible, not stuck in one position. Neural connections, over time, can get stuck in certain patterns. First we "shake up" the brain by giving it random pulses, then calm it with steady, slow waves. The brain enjoys that, thus mimics the induced frequencies post-therapy. This is Neuro-Field Therapy.
Daily Schedule: 6:30am Yoga, 3 organic meals/day, 5:15pm Mindfulness Training.
So far: One Neuro-Feedback and one Neuro-Field Therapy session.
How am I?....I had a melt down today....After the first treatment, the "volume" turned down in my mind. The places my mind had been going to that were causing me stress weren't an option. With so much space, I just felt so sad, spacey and tired. Not in my power. Could be from so much travel, my body's hormone changes, a new environment. Why do I feel threatened even when I am perfectly safe?
My dreams have been startlingly vivid and revealing.
Hello, sweetheart. I haven't wanted to speak these last days as it's been quite an experience over here. I'm doing well and learning a lot. Holding the role of student and learning teacher AND kitchen assistant is not ideal. But, it's beautiful and rich in all the ways you can imagine. Had a melt down today and asked for support (from our wonderful yoga instructor/life coach, Kate). Gosh, that is so hard for me. Learning a lot about my self-critical part/perfectionist who wants to, and usually can, do it all, then gets overwhelmed and keeps it to myself because I don't want to let anyone down or appear the failure. All stuff we are working on my brain with. It's actually deeply engrained neuro-firings that create this behavior and by calming down areas of the brain, the volume of the self critic turns down. Removing obstacles to true perception. Intriguing stuff. I've been told that I'm extremely sensitive and so they are taking my therapy slowly. I'll do something like 12 sessions over 4 weeks time.
So, it's quite amazing that I've become the person I've become. It takes so much courage to want to change ourselves. It's quite easier to stay the same and comfortable, even though it ultimately creates more discomfort.
"It's obvious you're a mediator," I was told by Sarah upon viewing my brain "map."
This is good because apparently, my "fight or flight"/sensory motor area of the brain is overactive. This can be from life-long patterns stemming from childhood trauma. AND I'm low on dopamine (a neuro-chemical that creates feelings of well-being). No wonder I've felt whacked!!!
I had my second Neuro/Bio Feedback treatment today. We are working to calm down that fight/flight area and the area that is the self-critic. Yes, please. To shift from Delta brainwaves to Alpha and Beta waves, move the activity around and make space for clearer thinking. Uh, yeah, that will be wonderful.
With my brain make up, it is no wonder that my body and mind love and gravitate toward yoga and meditation. It gives me solace and relief. Alpha waves are prevalent during meditative states. Alpha brainwaves are slightly faster. This is the state of mind when we are "in the now." Some call it "open focus." For practiced meditators, Alpha is always present.
The most significant thing to report today is around my body's well-being. One month ago, I started having hot flashes, a pre-menopausal symptom and a signal from the endocrine system that can indicate a woman's shifting out of child-bearing stage (Gentlemen who love the feminine, take note). Intense!!! At 43 years of age, this is quite young to be having these symptoms. Sarah recommended raw, organic maca root taken by tspn each day. My body has been calm, no hot flashes, for 2 days now. Could be a combination of no caffeine and alcohol (which can be contributing factors) AND the neuro-feedback treatments, which help to balance neuron-hormones as well.
In all, energized & positive, 2 hour nap on veranda, a close encounter with a hummingbird, intensity of dreams continuing.
Here's a nifty little secret...I have experienced 1 Vipasana (10-day silent meditation retreat) and MANY yoga classes, trainings & workshops, but I've never been a student in a yoga retreat. I teach them, I organize them, I run a yoga retreat center, yet this is the first I've experienced one as a (semi) student. The dedication of daily practices alone are shifting me. I am waking without my mind racing to the long list of "to doobey do's." My body feels incredible, light and strong, clean and clear. Even though I've been working throughout the week (participants usually do not), I've been able to step back, look at some current challenges more objectively and approach them with logic and ease.
Whaddayaknow?....This stuff really works! Okay, could have something to do with the neuro-therapy, as well. Although we've only been able to fit in 2 sessions for me personally, I am told they continue to work long after. The brain LIKES the shifts the therapy allows it to feel, therefore continues to move in that direction without stimulation.
Goodnight, sweet brain.....I am so happy to be taking great care of you.
Care and feeding of the brain: Post-care was covered today at lunch. It's recommended to avoid or limit alcohol intake for at least a month. It's not that alcohol will reverse or undue the work that has been done, but for about a day after drinking it, the progress will come to a stop. Alcohol inhibits healthy brain function (obviously!) and it slows the formation of the new pathways that are being forged from the therapy.
The good news is that the work will continue. The ways in which our brains have learned to function, turning down here, turning up there, etc., will enhance over the next 4-6 weeks, becoming stronger and more deeply engrained patterns. I like that.
Today, I feel the biggest shift. My mood is steady. The self-critical voice is dialed way down or not present. I lead our Mindfulness Training/Closing tonight with the group and it was pure pleasure. I'm grateful to be witness to the transformations around and within me. Teaching yoga in the morning....what dreams may come this night?
Taught 6:30am yoga today around the theme of "Transition," staying present in the "in-between" places as we journey from one location to another, one asana to the next. Ate our final scrumptious meal prepared by Sara (I will miss learning in the kitchen with this wise woman!) and said our sweet goodbyes. Wrapped up a lovely morning by clearing the space we've shared together, opening it up once again to be blessed by all who enter.
It's now 10 days from the retreat, I've had 2 more neuro-therapy treatments with about 6 more or so to go. What I'm noticing is an ease in my being and a realization that, prior to the retreat, I was depressed. It's one of those things that you don't see when you're in the middle of it. Kind of like emerging into bright sunshine after being in a thick cloud of fog. I didn't know I was so depleted until my body and mind felt better. Looking back, I see that recent intense life challenges, hormonal changes and edging toward empty in the dopamine tank created the perfect storm for anxiety and depression.
In a world where anxiety, depression, asperger syndrome, autism and many social, mental and emotional disorders are on the rise, I applaud Sara and James Roy for courageously bringing this cutting edge therapy to the public. I am, as well, so grateful to have crossed their paths and to be forging new paths in my own brain's journey into greater well-being.
Keep an eye out for 7 Tips for a Healthy Brain. What you can do to promote your own brain's health, support your nervous system and just plain feel better!
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On the last Friday of every month, starting on 29 June, it will be possible to visit the Arab Wall hidden in the interior of Vincci Posada 5*. The visits are free, only requiring prior registration. Underneath Vincci Selección Posada del Patio 5* lies the largest and best preserved section of city's Arab wall, the only part which can be visited from both sides. The initiative is part of our hotel chain's commitment to the European Year of Cultural Heritage to facilitate access to and promote the value of the heritage of our properties in line with the aims set out by the main European institutions.
The visits are aimed at everyone, both guests and the general public, who wants to find out more about the history of the city. Each group is limited to a maximum of 20 people. The visits are free, you just need to register beforehand, sending a message to the following e-mail: muralla@vinccihoteles.com. The visits will last some 15-30 minutes, and as well as having a guide, the visitors can further explore the history of the wall by activating the Bluetooth on their smartphone. The wall has a device that streams information at certain points of the tour to mobile phones.
These open days also offer the possibility of exploring various aspects of the medieval buildings which were discovered during the works to renovate the hotel, in 2007 and 2008. They will also reveal curiosities such as how low the building is compared to sea level, meaning there is a need to have pumps to maintain the water table, to avoid it flooding. The director of Vincci Selección Posada del Patio 5*, César Pérez said "maintaining the wall inside the hotel was the most difficult option, but the one chosen to showcase the value of this landmark of such historical value. The work of the archaeologists who catalogued both the remains of the wall, along with the other articles discovered, slowed down the work, but allowed all the items discovered to be recovered and returned to the city as part of its history". The section of the wall underneath Vincci Posada is one of the visits recommended by the city council.
Located in the historic centre of Málaga, Vincci Selección Posada del Patio 5* is built on the site of two ancient buildings. One of these was one of the last posadas (old style inns) that existed in Málaga, while the other was a residential building, of which the façade from the start of the 20th century has been preserved. It's been entirely renovated, preserving the patio that gives it its name and the old hall from the entrance on Calle Camas.
Under the two buildings were found remains of Málaga's Arabic wall, together with remnants of the old Puerta del Río, as well as an old tannery and various utensils which are on display in the hotel. The property has 106 room which include every convenience to ensure a unique experience and its á la carte restaurant "Le Diner" is the perfect place to savour the best of Málaga's cuisine with a touch of sophistication. The hotel also has a rooftop terrace with a swimming pool, offering the finest views of Málaga, along with the possibility of a refreshing dip.
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