Hi, I would like to understand how to best configure the shipping system for the marketplace.
Let's have two sellers (SellA and SellB). I have configured the shipping rules by entering 3 types of shipping (ShipA, ShipB, ShipC).
Now I would like for SellA to choose ShipA and ShipB shipments for its products and the second seller ShipB and ShipC, they will also be able to choose the price for their shipments.
But with this configuration I show all shipments with the sum for each seller.
Which is the right configuration?
There's seller filter in shipping rules. You need to select the SellA in ShipA and ShipB while SellB in ShipB and ShipC. After this, these rules will be applied to filtered seller's products.
And select itemised shipping in global configuration > Yes. So, customer can select the available shipping rates only.
I'm sorry, but maybe I explained myself badly. I had already seen the filters to be applied to the shipping rules about the seller, but I have to do this.
What I would like to do is show the seller a list of possible shipments that you can apply to his products and enter his cost for shipping. Basically like it happens with ebay.
Also at checkout I would like the products in the cart to be grouped by seller and shown the shipping services offered.
If in the global configuration I select "itemised shipping" to NO, I check below "Shipping Cost Calculation" where I can select "Group item by seller" which is exactly what I want, but unfortunately it is not shown in this way.
No reply? Need other information?
I also have the same issue. If the customers orders few different products from the same seller, then the price should be calculated as package of the products. The option, as mentioned by Gaeteno, is there; but it does not seem to be working.
Please guide us, if we are doing any misconfiguration.
I have checked the configuration Gaetano and Arshad are talking about, and this is working on the sellacious version 1.6.0. This setting is to calculate shipping internally.
Like if in basic shipping rule, the cost is 5$ with additional cost 2$.
Now, in cart add 2 products of seller-1 and 2 products of seller-2, calculation of shipping will be 14$, (5+2) for both sellers.
However, if the setting is 'Entire cart as 1' calculation would be 11$.


Shooting into the sun can produce some very dramatic effects and present some difficult exposures for you. I use the sun as a design element, which plays an important part in the overall composition of the image.
An exposure from an image like the one shown above would most likely be something like, 1/250th @ f/22.0 at ISO 100. I really like getting that star effect off the sun, the only way to get this effect is to use a steep or deep aperture like f/22.0, f/16.0, or f/11.0. The steep or deeper the f-stop, the more the star effect.
The EXIF data on this image says that I shot this photo at 1/160th @ f/22.0. I used an SB-800 to lite my subject, and the flash way just outside of the frame of the image. If I am not mistaken, I think the flash was set to about 1/2 or 1/4 + 2/3. The flash had no modifier on it so it was a direct flash.
In the image above, my assistant John was on an adjacent tank on top with an SB-800. I used a Radio Popper to trigger the flash as I was not in line of sight of the flash. Often when shooting is strong sunlight, the CLS system falls short and a third party system is called for.
In the above photo, I had John stand next to me with a monopod extended in the air above the bent pipe with an SB-800 on it. From this position, I was able to use the Nikon CLS system to trigger my strobes.
I've been on the road quite a bit these past few weeks, and I have more travel ahead of me. I've been in East shooting stills and video for a new Oil & Gas client. This past week I was shooting in Pennsylvania, West Virgina, and Kentucky.
I was photographing various gas processing plants for my client, I visited 5 different plants on this trip. Shooting video is new to me, I was shooting mostly B-roll material with out sound. I actually had fun doing it, however I have no plans on developing it any further then the basics.
Here are a few images from this recent trip.
I'll be leaving for Austria next Monday, I have 4 workshops and a speaking engagement in Vienna for Nikon. I am very excited to be speaking to a large group of photography enthusiasts, let alone in Vienna. As I mentioned, I'll be holding 4 Small Strobes, Big Results workshops in Austria. You can find out more information about these workshop HERE.


Should I update my software?
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Companies often release updates to improve security. Keeping your software up to date ensures hackers cannot exploit old vulnerabilities to steal your data.


I will be following your beef chronicles. I have never bought beef other than at the butchery, but it seems like a great experience to buy it directly at the farm.
We get quarters of beef from our friends, so I'm well-acquainted with a beef-overload in the freezer. Have you ever made peposo? It's simply beef, garlic, lots of black pepper, salt, and red wine thrown together and simmered in the oven for a long time. It's divine.
That freezer is lookin' good. I don't eat much red meat, but every few months or so I like a bit of beef. Looking forward to the recipes!
You're so organized! I still haven't even opened my fourth bag. I have no idea what's in it!
Now, why are the heart and other organs in parentheses? Are you unsure of whether you will include them?
For the carpaccio, you need fresh and never freezed meat, as same for tartare.
For veal cube, put all the ingredients in a Crock-pot. Onions, carrots, garlic, celery, potatoes, even tomatoes and add some veal stock or water. Salt and pepper, herbs and spices.
Oh, geez that's a lot of beef. While my honey enjoys his beef, I'm on the other end of the scale that wants just the mushrooms and the kiddos are somewhere in the middle.
I'll be following along to see what you come up with. Good luck Aimee!
Yum. You've pretty much summer up Morgan Heaven. Shocker, right?
I'll be inrigued to see what you do with T-Bones, I usually avoid them because I'm lazy when eating. If it isn't edible I don't want it on my plate at the end of the meal. And minute steak? I only know the one way my mom did it, pan fried and in tomatoe sauce. And I disliked it very much as a kid.
ROFL @ "getting groped with some Montreal Steak Spice and merely slapped on a grill"
My mom has a mean beef heart soup recipe, I'll get it to you tonight. Beef heart is very lean, if not the leanest meat you can get from a cow. I find the texture really tender and smooth. Well, from what I remember from the last time I had my mom's soup anyways, must be a few years now. But go ahead and try the beef heart, it's great!
Hi Isabelle- Thanks for joining in! This was our first time to buy directly from a farm and so far we are really happy.
Hi Mama JJ- Mmm, peposo sounds great! simple and elegant.
Hi Hilary- Thanks for stopping by. I hope I can inspire some beef cooking in you!
Hi Jess- Well, it's all talk so far, right? Talk is easy!
Hi Michele- Right. like I said, they are intended for the cat, unless I get truly inspired and very brave.
I know, how un-Julie Powell of me.
Hi annie67- Sounds like directions for a killer stew. Thanks!
Hi Ingrid- Thanks for commenting! Maybe your hubby's going to follow along, eh?
Hi Nutmeg Nanny- Thanks so much for the instructions. I MAY thaw to the idea of eating heart.
Hi Cheryl- Hah! Morgan heaven. Most guys probably, too.
Hi Chocolatesa- Thanks for stopping by UtHC! And for the promise of a recipe. Very sweet of you.
Here's the recipe, an adapted version from from Pierre & Janet Berton's Canadian Food Guide, my mom's copy that she gave to me.
Take 1 beef heart, put it in a big pot, cover with water, boil for 24 hours, keeping covered with water. Remove heart from water, keep broth. Take a blunt knife, scrape off fat from beef heart. Cut in half, remove blood vessels, and then cut into 1" cubes, and put them back into the broth. Add beef broth/bullion cubes/powder to taste, diced potatoes, chopped onion, herbs (sage,thyme, rosemary), parsley, carrots, then cook until veggies are done, salt and pepper to taste, and serve hot.
The original recipe calls for celery, turnip, green pepper and chives, which I haven't tried yet.
Wow, that sounds almost like a Julie/Julia project.
What you really should do, though, is get a Foodsaver and properly freeze the stuff, as there's no way you're going to be able to eat all that within three months, and you want to avoid freezer burn.
I'm very jealous. Last time I checked I'm not a butcher, but almost everything you suggested sounds good (well, liver and let liver).
This is one I'll be following.
Uhh, any chance there's a space at the table, say, next Tuesday . . . . ?
Fun endeavor! We rarely eat beef at home, maybe once or twice a month, but I'm really looking forward to seeing what you come up with. It'll probably inspire me to try it out more often too.
Oh my goodness...you have some tasty dinners in your future.
My hubby's family are beef farmers. Would love to see e=what creative thing you come up with!
For all the stewing veal, well, for the grade you've got, you can just re-cube it a bit smaller and stir fry it. For extra decadence, stir fry in bacon fat (instead of olive oil) with thyme and tarragon, salt to taste, cook covered until done (stirring occaisonally) and serve over rice. One douses the rice with the liquid in the wok, or saves it to cook the rice in next time.
Or you can wait until things are a bit cooler and make soup; beef-parsnip-carrot soup is a fine thing and really doesn't much care about the grade of beef.
What a great idea - looking forward to reading more!
Beef heart is really delicious. We make a guajillo sauce and eat it in tacos.


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redpajama_set_name: RedPajamaCommonCrawl


text:
Q: How to show there are irreducible polynomials of any degree over $\Bbb Z _p$? How do I show there are irreducible polynomials of any degree in $\mathbb{Z}_p[x]$, with $p$ prime?
I tried counting the number of reducible polynomials of any degree but that turned out to be hard... Any help?

redpajama_set_name: RedPajamaStackExchange


text:
\section{\label{sec:level1}Introduction}

Laser plasma acceleration of charged particles is one of the most promising areas of ultraintense lasers applications \cite{malka2008principles}. Today the most popular electron acceleration schemes are laser wakefield acceleration (LWFA \cite{doi:10.1063/1.37621}) and direct laser acceleration (DLA \cite{doi:10.1103/PhysRevLett.83.4772}). While the LWFA with 1 PW laser has been shown to produce high-quality quasi-monochromatic electron bunches with energies up to 8 GeV \cite{PhysRevLett.122.084801}, a divergence of 0.2 mrad and charge of several hundred pC, the DLA usually yields the quasi-exponential energy spectrum, but much higher charges (up to hundreds of nC \cite{doi:10.1088/1367-2630/abdf9a}). It is also can be implemented on tabletop femtosecond laser systems with 1-10 TW peak power \cite{doi:10.1088/1361-6587/ab1e1d, tsymbalov2020efficient}.

One of the key issues for either acceleration scheme is the injection of the initial electrons \cite{doi:10.1063/1.3469581} since it strongly determines the parameters such as charge, energy, and divergence of the  electron beam obtained. The most established injection schemes to date are ionization injection \cite{doi:10.1088/0741-3335/58/3/034011} and wavebreaking of plasma waves \cite{doi:10.1103/PhysRevE.58.R5257}. Both in principle can be used for the DLA, however, ionization injection yields electrons with a low (few eV) initial energy, while wavebreaking -  subrelativistic ones.

The optimum conditions for injection of high-energy electrons for the DLA are well discussed \cite{doi:10.1063/1.874154, doi:10.1063/1.873242, doi:10.1063/1.4964901, doi:10.1063/1.4975857, doi:10.1103/PhysRevE.98.033206,doi:10.1088/0741-3335/56/8/084006, doi:10.1103/PhysRevAccelBeams.24.041301, doi:10.1103/PhysRevLett.114.184801, doi:10.1088/1361-6587/aad76f, doi:10.1063/1.4766166, doi:10.1017/S0022377815000434, doi:10.1063/1.4951715}.
It has been noted that the energy gain obtained by electron depends on the phase of the laser field it has been injected into \cite{doi:10.1017/S0022377815000434,doi:10.1088/1361-6587/aad76f}. Rigorous theoretical analyses for the specific DLA models have shown that the energy gain depends specifically on the relative phase of the laser radiation and the Eugen electron's oscillation in the plasma channel \cite{doi:10.1063/1.874154,doi:10.1063/1.873242,doi:10.1063/1.4964901}.
Besides of the injection phase, the optimal initial electrons' energies have been also analysed \cite{doi:10.1063/1.873242,doi:10.1063/1.4964901,doi:10.1063/1.4975857,doi:10.1103/PhysRevE.98.033206,doi:10.1088/0741-3335/56/8/084006,doi:10.1103/PhysRevLett.114.184801,doi:10.1088/1361-6587/aad76f,doi:10.1063/1.4766166,doi:10.1017/S0022377815000434,doi:10.1063/1.4951715}. Role of the electron transverse energy in the acceleration was demonstrated analytically \cite{doi:10.1063/1.873242} and the results \cite{doi:10.1063/1.4975857,doi:10.1088/0741-3335/56/8/084006,doi:10.1103/PhysRevLett.114.184801,doi:10.1088/1361-6587/aad76f} indicated that the optimal electron's injection condition corresponds to a quite large value of its transverse energy: $p_{0 \perp}/mc \approx (4 \div 6)$ ($m$ - electron mass, c - speed of light). Here and below $\perp$ and $\parallel$ notation indicate the direction perpendicular or parallel to laser radiation propagation direction, respectively. Several works have also demonstrated an importance of the electron initial longitudinal momentum for acceleration \cite{doi:10.1103/PhysRevLett.114.184801,doi:10.1063/1.4951715}. In \cite{doi:10.1063/1.4951715} it was highlighted that electrons are accelerated most efficiently when injected at small angels to the plasma channel axis: $p_{0 \perp}/p_{0 \parallel}\approx (0.15 \div 0.40)$.  All mentioned results demonstrate the possibility of an efficient energy gain by already pre-accelerated electrons.

However, there is not much discussion of the DLA of low-energy (i.e. created after ionization) electrons. To our knowledge, the only work in which this effect was discussed explicitly is \cite{doi:10.1063/1.4964901}. Therefore the goal of this paper was to understand the feasibility and optimal conditions for the ionization injection in DLA.
We extensively analyzed the simplified DLA model for the case of electrons with low initial energies, reducing it to a qualitative analysis of the motion of an electron in a plasma channel. Further studies were conducted by analyzing resulting phase portraits. We also developed techniques to select a phase portrait topology corresponding to the acceleration of low-energy electrons at an extended range of initial phases. Therefore parameters at which ionization injection of electrons in DLA can be efficient were established. Developed approach in principle can be used to describe and optimize DLA electron acceleration for arbitrary initial and final energies.

\section{Motion of relativistic electron in the plasma channel}%

Let us first describe the basic interaction scenario and simplified analytical model of the DLA. When a high-intensity laser pulse interacts with the target and its power significantly exceeds the power of self-focusing, the formation of a plasma channel is possible \cite{doi:10.1063/1.871727}. The ponderomotive action of the laser pulse pushes electrons off the axis, thereby forming a radial electric field. Electrons that move along the direction of propagation of the laser pulse create an azimuthal magnetic field. Electrons moving in a combination of these fields under certain conditions experience energy gain. This is the essence of the DLA \cite{doi:10.1103/PhysRevLett.83.4772} mechanism.

Let us consider a symmetric infinitely long hydrogen plasma channel along z-axis with static radial electric and azimuthal magnetic fields:
\begin{equation}\label{e1}
   E^{s}_x=-2e\left( n_{e_{in}}-n_{e_{out}}\right) \pi x
\end{equation}
\begin{equation}\label{e2}
   B^{s}_y=-2en_{e_{in}}\pi x
\end{equation}
where $n_{e_out}$ - electron density outside the channel, which is equal to ion density in our model, $n_{e_in}$ - electron density inside the channel, $e$ is electron  charge. We will consider an electron moving in an $y=0$ plane.
It should be noted that in the model of hydrogen plasma we can neglect ionization by laser radiation.

Laser radiation is defined as an uniform plane wave:
\begin{equation}\label{e3}
   E^{L}_x=E_0^{L}\exp{\left(i\left(\omega t-kz\right)\right)}
\end{equation}
\begin{equation}\label{e4}
   B^{L}_y=\eta E_0^{L}\exp{\left(i\left(\omega t-kz\right)\right)}
\end{equation}
where $E_{0}^{\left( L\right) }=A\dfrac{\omega }{c}$ - laser electric field amplitude, $m$ is electron mass, $A$ - vector potential amplitude,
$\eta$ - plasma refractive index ($\eta=\sqrt{1-n_{e_in}/n_{cr}}$).

\begin{figure}[b]
\includegraphics[width=1\linewidth]{xyz}
\caption{\label{fig1} The schematic view of the plasma channel with electric and magnetic fields}
\end{figure}

This model uses a lot of approximations. The main ones are: (i)  the plane wave is a very crude description of a real laser pulse, and (ii) the plasma channel fields are in fact not static. However, it can be shown that such model can successfully predict maximum achievable electron energy gain in more realistic conditions \cite{doi:10.1063/1.874154}. Moreover, the indisputable advantage of this simple model is the possibility to study it analytically. Below we will demonstrate how by employing rather simple calculations one can estimate optimal initial parameters required for effective acceleration of electrons and get a deeper insight on the parameters that affect injection for the DLA.

An electron motion in the combination of the static plasma channel fields and electromagnetic laser fields  \eqref{e1}-\eqref{e4} can be described as:

\begin{equation}\label{eq11}
\dfrac{dp_x}{dt}=-e\left[ E_{x}^{s}+E_{x}^{ L}-\dfrac{v_{z}}{c}\left( B_{y}^{s}+B_{y}^{L}\right) \right]
\end{equation}
\begin{equation}\label{eq2}
\dfrac{dp_{z}}{dt}=-e\dfrac{v_{x}}{c}\left(B_{y}^{s}+B_{y}^{L}\right)
\end{equation}
\begin{equation}\label{eq1}
mc^{2}\dfrac{d\gamma}{dt}=-e\left( \textbf E\cdot \textbf v\right) =-e v_{x}\left( E_{x}^{s}+E_{x}^{L}\right)
\end{equation}
where $\gamma=\sqrt{1+\dfrac{p_{x}^{2}+p_{z}^{2}}{m^{2}c^{2}}}$ - Lorentz factor. Electron trajectory will be that of anharmonic oscillator with Eugen frequency $\omega_b=\dfrac{\omega _{p}}{\sqrt{2\gamma}}$, which is named betatron frequency in the DLA case, and driving force frequency $\omega - kv_z$, where $\omega _{p}=\sqrt{\dfrac{4\pi e^{2}n_{i}}{m}}$ - plasma frequency.

Eqs. \eqref{eq11}\eqref{eq2}\eqref{eq1} have an integral of motion \cite{doi:10.1063/1.4964901}:
\begin{equation}\label{eq3}
I_{0} =\gamma +\dfrac{e^2\pi}{mc^{2}}\left( n_i-n_e(1-\dfrac{1}{\eta})\right)x^{2} -\dfrac{p_{z}}{\eta mc}
\end{equation}

Note that the second term in \eqref{eq3} vanishes if $ x = 0 $, i.e on the plasma channel axis. Hereinafter we will assume that all the electrons start their motion with $ x(t=0) = 0 $.

\section{Injection and DLA  in the phase space}
Now we will use this model to study low-energy electron injection in DLA using phase portraits.
Following \cite{doi:10.1063/1.874154} we applied the WKB approximation to simplify description of transverse motion of electrons using approximate expression:

\begin{equation}\label{eq12}
   x\approx \frac{v_{xA}(\gamma)}{\omega_b}sin\left(\int{\omega_b dt}\right), v_x\approx v_{xA}(\gamma)cos\left(\int{\omega_b dt}\right)
\end{equation}
where $v_{xA}$ - amplitude of an electron electron transverse velocity.

Using \eqref{eq12} and time-averaging over betatron oscillation period, equation \eqref{eq1} can be reduced to the system of two equations:
\begin{equation}\label{eqq4}
\dfrac{d\gamma }{dt}=-\dfrac{eE_{0}^{\left( L\right) }v_{xA}\left( \gamma \right) }{2mc^{2}}\cos \Phi
\end{equation}
\begin{equation}\label{eqq5}
\dfrac{d\Phi }{dt}=\omega -\omega _{b}-kv_{z}
\end{equation}
where $\Phi=\omega t-\int\omega_b d t-kz+\Phi_0$, $\Phi_0$ is an electron initial condition, which depends on initial phase of betatron oscillation ($\int\omega_b d t$) and initial phase of electromagnetic wave ($kz(t=0)$)  at which electron was injected. Equations \eqref{eqq4} and \eqref{eqq5} describe time evolution of an electron energy and the phase shift between the Doppler-shifted laser field and electron betatron oscillations.

\begin{figure}[b]
\includegraphics[width=0.49\linewidth]{vxAgamman=0.99I=1.0}
\includegraphics[width=0.49\linewidth]{vxAgamman=0.99I=0.5}
\caption{\label{fig2}Dependence of the electron betatron oscillation velocity amplitude $v_{xA}$ on $\gamma$ calculated from \eqref{eq6} (blue), \eqref{eq7} (orange) and with $v_{xA}=0.2c$ (green)  \cite{doi:10.1063/1.874154} at  $\eta=0.99,  I_0=1.0$ (a), $\eta=0.99,  I_0=0.5$ (b). Red colored area in figure \ref{fig2}b indicates forbidden $\gamma$ values in \eqref{eq6}.}
\end{figure}

In  \cite{doi:10.1063/1.874154} $v_{xA}$ was considered to be constant. This is valid only for electrons with high initial energies ($\gamma \gtrsim 80$, see Figs.\ref{fig2}a,b). It is, however, not valid for electrons with low initial energies, which are the main focus of our work. In order to study the DLA of such an electrons one can express $v_{xA}$ from the integral of motion $I_0$ \eqref{eq3}:

\begin{equation}\label{eq6}
v_{xA}(\gamma)=c\sqrt{1-\dfrac{1}{\gamma ^{2}}-\eta ^{2}\left( 1-\dfrac{I_{0}}{\gamma }\right) ^{2}}
\end{equation}

The resulting dependence $v_{xA}(\gamma)$ is shown in Fig.\ref{fig2} in blue.
The system  \eqref{eqq4}--\eqref{eq6} can be solved numerically only. However, when electron transverse velocity $v_{xA}$ is much less than the speed of light, the paraxial approximation can be used \cite{doi:10.1063/1.4964901}:
\begin{equation}
v_{x}^{2}+v_{z}^{2}\approx c^{2}
\end{equation}
\begin{equation}
\dfrac{v_{z}}{c}\approx 1-\dfrac{v_{x}^{2}}{2c^{2}}
\end{equation}
\begin{equation}\label{eq7}
v_{x_{A}}\approx c\sqrt{2\left( 1-\eta \left( 1-\dfrac{I_{0}}{\gamma }\right) \right) }
\end{equation}
The dependence $v_{xA}(\gamma)$  \eqref{eq7} is shown as orange line in Fig.\ref{fig2}. One can see that the paraxial approximation can not be used for low-energy electrons, which are precisely the ones that we get from ionization injection. However, the difference between the approximate \eqref{eq7}  and exact \eqref{eq6} solutions is less than 10\% for $\gamma>5$.
 Further, we will discuss that why this discrepancy can be neglected and hence equation \eqref{eq7} would still be applicable.

\section{Phase space investigation of DLA}

System of equations \eqref{eqq4},\eqref{eqq5},\eqref{eq7} can be solved analytically, with the solution being:
\begin{equation}
\sin \Phi =F\left( \gamma \right) -\alpha
\end{equation} where $F\left( \gamma\right)=-\frac{I_{0}\eta(\eta-2)\ln\left(\sqrt{\left(1-\eta\right)\gamma+I_{0}\eta}+\sqrt{(1-\eta)\gamma}\right)}{\sqrt{2}a_{0}\sqrt{1-\eta}}$
$+\frac{\left((\eta-1)(\eta+2)\sqrt{\gamma}+2\sqrt{2}\frac{\omega_{p}}{\omega}\right)\sqrt{\left(1-\eta\right)\gamma+I_{0}\eta}}{\sqrt{2}a_{0}(1-\eta)}$

The quantity $\alpha$ characterizes the trajectory in the phase space ($\gamma,\Phi$) for a given initial values of $\gamma_0,\Phi_0$ and  can be found as:
\begin{equation}\label{eq13}
\alpha=F\left(\gamma_0\right)-\sin \Phi_0
\end{equation}

It is convenient to use the phase space $(\gamma,\Phi)$ to study this system \eqref{eqq4}\eqref{eqq5}\eqref{eq7} (see Fig.\ref{fig3}). Each curve (phase trajectory) in Fig.\ref{fig3} represents evolution of the system for a specific initial conditions. Singular points (i.e. equilibrium states) of the system \eqref{eqq4}\eqref{eqq5}\eqref{eq7} can be found as:

\begin{equation}
\Phi _{cr_{1,2}}=\pm \dfrac{\pi }{2}+2\pi h
\end{equation}
\begin{equation}\label{eq20}
\gamma _{cr_{1,2}}=\dfrac{2\eta ^{4}I_{0}^{2}}{\left( \dfrac{\omega _{p}}{\omega }\mp \sqrt{\dfrac{\omega _{p}^{2}}{\omega ^{2}}-4\eta ^{2}I_{0}\left( 1-\dfrac{\eta }{2}-\dfrac{\eta ^{2}}{2}\right) }\right) ^{2}}
\end{equation}
where $h$ is an integer.
The points $\left( \Phi_{cr_2},\gamma _{cr_{1}}\right)$, $\left( \Phi_{cr_1},\gamma _{cr_{2}}\right)$ are centers (pink dots in Fig.\ref{fig3}). The points $\left( \Phi_{cr_1},\gamma _{cr_{1}}\right)$, $\left( \Phi_{cr_2},\gamma _{cr_{2}}\right)$ are saddles (yellow dots in Fig.\ref{fig3}). Separatrices (red and green curves in Fig.\ref{fig3}) pass through the saddle points and divide the phase-space into the regions, where the system behaves differently:
\begin{equation}
\sin \Phi -\sin \Phi _{cr_i}=F\left( \gamma \right) -F\left( \gamma _{cr_i}\right)
\end{equation}

\begin{figure*}
\includegraphics[width=1\linewidth]{AnPhaseSpace1}
\caption{\label{fig3}Phase portraits of the system \eqref{eqq4}\eqref{eqq5}\eqref{eq7} ($\eta=0.99$, $n_i=0.1n_{cr}$) for  $I_0=1.0$ (a),  $I_0=I_{0cr}=1.187$, where $I_{0cr}$ is $I_0$ value for homoclinic-heteroclinic bifurcation to occur (b),  $I_0=1.3$ (c),  $I_0=I_{0f}=1.706$, where $I_{0f}$ - $I_0$ value at which singular points merge (d).  Blue curves - phase trajectories for different values of $\alpha$ \eqref{eq13}, indicated as numbers. Red and green curves - separatrices, pink dots - center points, yellow dots - saddle points.  Orange curve in  Fig.\ref{fig3}c represents phase trajectory of interest for our study. Black asterisk marks  the maximum electron energy for this trajectory.}
\end{figure*}

For the considered system of equations, the topology of separatrices can be both heteroclinic (i.e. separatrix passes through each saddle once, see Fig.\ref{fig3}a) and homoclinic (i.e. separatrix passes through each saddle twice, see Fig.\ref{fig3}c), depending on the initial parameters. Figure \ref{fig3}b shows heteroclinic-homoclinic bifurcation of the phase portrait \cite{doi:10.1137/0521010}  (i.e. separatrix reconnection), through which these topologies switch. It takes place when separatrices pass through both saddles $\gamma_{cr_1}$ and $\gamma_{cr_2}$ and therefore merge. Hence one can find the $I_{0cr}$ value for this bifurcation to occur:
\begin{equation}\label{eq15}
2=F\left( \gamma _{cr_{1}}, I_0=I_{0cr}\right) -F\left( \gamma _{cr_{2}}, I_0=I_{0cr}\right)
\end{equation}

A further increase in $I_0$ leads to the merge (i.e. $\gamma _{cr_{1}}(I_0=I_{0f})=\gamma _{cr_{2}}(I_0=I_{0f})$) and disappearance of singular points and, correspondingly, separatrices (Fig\ref{fig3}d). It occurs at:
\begin{equation}\label{eq16}
    I_{0f}=\dfrac{\omega _{p}^{2}}{4\omega ^{2}\eta ^{2}\left( 1-\dfrac{\eta}{2}-\dfrac{\eta ^{2}}{2}\right) }
\end{equation}

Electron acceleration regime of interest corresponds to Fig.\ref{fig3}c, as there exist phase trajectories (see, for example, the orange curve in Fig.\ref{fig3}c) connecting $\gamma \approx 1$ with large $\gamma$ values, with maximum attainable electron energy marked with a black asterisk. The phase portrait topology shown in Fig.\ref{fig3}a wouldn't be discussed further, as low-energy electrons are not captured there. Let us note, however, that it can still be used if one studies acceleration of electrons with larger initial energies ($\gamma >> 1$). The topology of the phase portrait after the merging of singular points (Fig.\ref{fig3}d) is poorly suited for acceleration, since electrons do not experience a substantial energy gain compared to other topologies.  It's important to remember that $I_{0cr}$ and $I_{0f}$ heavily depend on the plasma channel parameters (specifically $\eta$ and $n_i$).

\begin{figure}[b]
\includegraphics[width=1\linewidth]{I0}
\caption{\label{fig4} $I_0$ and $\gamma_0$ in the ($p_{x0}$,$p_{z0}$) coordinate plane. For every fixed $I_0$ (blue curve) $\gamma_0$ value can be greater than or equal to the red circle radius}
\end{figure}

We should also note that $I_0$ \eqref{eq3} and electron initial energy $\gamma_0$ are, in fact, dependent on each other. The easiest way to show this is to express them through initial transverse $p_{x0}$ and longitudinal $p_{z0}$ momenta:

\begin{equation}
    I_{0}=\sqrt{1+\dfrac{p_{x0}^{2}+p_{z0}^{2}}{m^{2}c^{2}}}-\dfrac{p_{z0}}{mc\eta }
\end{equation}
\begin{equation}
    \gamma _{0}=\sqrt{1+\dfrac{p_{x0}^{2}+p_{z0}^{2}}{m^{2}c^{2}}}
\end{equation}

In coordinate plane ($p_{x0}$, $p_{z0}$) $I_0 = const$ is a hyperbola and $\gamma_0 = const$ is a circle (see Fig.\ref{fig4}). For a fixed $I_0$ only phase portraits with $\gamma_0 \geq \frac{-I_{0}+\sqrt{2 I_{0}^{2}-\eta^{2} I_{0}^{2}+1-\eta^{2}}}{1-\eta^{2}} $ would exist. As we are interested in acceleration of electrons with initial energies close to zero (i.e. $\gamma \approx 1$), only $I_0\approx1$ would satisfy that requirement. As was discussed earlier, $I_0$ should also correspond to the phase portrait topology shown in Fig.\ref{fig3}c, i.e. $I_{0cr} \leq I_0 \leq I_{0f}$. These two conditions can be rewritten as:
\begin{equation}\label{eq8}
    F(\gamma_{cr1},I_0=1)-F(\gamma_{cr2},I_0=1)<2
\end{equation}

\begin{equation}\label{eq14}
    \dfrac{\omega _{p}^{2}}{4\omega ^{2}\eta ^{2}\left( 1-\dfrac{\eta}{2}-\dfrac{\eta ^{2}}{2}\right) }>1
\end{equation}
where \eqref{eq8} reflects that separatrix reconnection \eqref{eq15} had already occured, and \eqref{eq14} reflects that singular points haven't merged yet \eqref{eq16}.

\section{Initial phases range}

One additional thing to consider is the range of initial phases $\Phi_0$, with which electrons can be accelerated. If this range is narrow it will result in poor injection efficiency even if conditions \eqref{eq8},\eqref{eq14} are satisfied. As $\Phi_0$ is determined, in part, by initial betatron oscillation phase, which is random for every electron, it is necessary to find acceleration regimes where electrons within the widest initial phase range would be captured.

\begin{figure}[h!]
\includegraphics[width=1\linewidth]{Phase}
\begin{flushleft}
\caption{\footnotesize The lower part of the separatrices corresponding to the topology of \ref{fig3}c (red and green). Initial phase ranges for injection energy $\gamma_in$ (blue line) is located between yellow points.  Solid curves indicate separatrices that satisfy \eqref{eq9},\eqref{eq10} ($\eta = 0.99$, $n_i=0.07n_{cr}$, initial phase range greater of equal to $0-\pi$), dotted curves - ones that do not satisfy \eqref{eq9},\eqref{eq10} ($\eta = 0.995$, $n_i=0.04n_{cr}$). Yellow and brown dots mark extreme values for meeting these conditions.}
\label{fig5}
\end{flushleft}
\end{figure}

Now we will find the conditions under which this range of initial phases will be greater than $(0-\pi)+2\pi h$ (for $\gamma \approx 1$), i.e. injection efficiency would be $>50\%$ for electrons with an initial energy $\gamma\approx 1$. Fig.\ref{fig5} provides an illustration for this conditions. Required phase range $(0-\pi)$ lies between the two yellow dots. To capture electrons  within this range of initial phases (i) the minimum of red separatrix has to be be larger than $\gamma=1$ (i.e. larger than $(\pi/2,1)$, brown dot) and (ii) the green separatrix has to to cross the $\gamma=1$ line at points $(0,1)$ and $(\pi,1)$:

\begin{equation}\label{eq9}
    F(1,I_0=1)-F(\gamma_{cr1},I_0=1)>0
\end{equation}
\begin{equation}\label{eq10}
    F(1,I_0=1)-F(\gamma_{cr2},I_0=1)<1
\end{equation}

\begin{figure}[b]
\includegraphics[width=1\linewidth]{ni_ne}
\caption{\label{fig6}The range of plasma channel parameters (shaded area) at which effective ionization injection takes place (conditions \eqref{eq8}\eqref{eq14}\eqref{eq9}\eqref{eq10}) are met)}
\end{figure}

\begin{figure*}
\includegraphics[width=\linewidth]{px0_pz0}
\caption{\label{fig7} (a-d): The analytically obtained maximum energy versus initial momenta $p_{x0}/mc$, $p_{z0}/mc$ for the fixed initial phase $\Phi_0$:  $\Phi_0=-0.5\pi$ (a),  $\Phi_0=0\pi$ (b),  $\Phi_0=0.5\pi$ (c), $\Phi_0=1.0\pi$ (d).
(e-h): Corresponding numerically obtained maximum energy versus initial momenta $p_{x0}/mc$, $p_{z0}/mc$ for the fixed electron initial position $z_0$:  $z_0=-\lambda/4$ (e),  $z_0=0$ (f),  $z_0=\lambda/4$ (g),  $z_0=\lambda/2$ (h). Plasma channel parameters for all figures are $\eta=0.99$ $n_{e_{out}}=0.07n_{cr}$.}
\end{figure*}

Thus, there is a set of channel parameters for which the above conditions are met and effective ionization injection might happen (see Fig.\ref{fig6}). Let us note, that these electron density values lie between that commonly used in both DLA and LWFA acceleration: tenths of $n_{cr}$ for the DLA  \cite{tsymbalov2020efficient} and thousandths of $n_{cr}$ for the LWFA. However, the required electron density can be experimentally achieved, for example, using high-density gas jet.

Figure \ref{fig7}a-d shows the analytically obtained dependence of the maximum achievable electron energy (corresponds to the highest point on the phase trajectory; see, for example, black asterisk in Fig.\ref{fig3}c) from its initial momenta $p_{x0}$, $p_{z0}$ under the \eqref{eq8}\eqref{eq14}\eqref{eq9}\eqref{eq10} conditions ($\eta=0.99, n_i=0.07n_{cr}$). In practice one can achieve this maximum energy by cutting the plasma channel at a correct length. It is also seen that  electrons with $p_{x0}\approx0$, $p_{z0}\approx0$ and initial phases $0 \leq \Phi_0 \leq \pi$ are indeed accelerated up to $\gamma\approx200$ energies for these parameters.

The same dependence can also be obtained by numerically solving electron' equations of motion in a given fields of a plasma channel \eqref{eq11}\eqref{eq2}. Figure \ref{fig7}e-h shows such results (time range $0 - 2$ ps, $3*10^3$ steps). It can be argued that the maximum electron energies and corresponding initial momenta $p_{x0}(p_{z0})$, obtained from these two models, are in a good agreement.

What does not agree, however, is the initial phase range: no efficient acceleration takes place in Fig.\ref{fig7}a, but it's present in Fig.\ref{fig7}e. Firstly, this may be due to the fact that the initial phase $\Phi_0$ is determined both by the phase of the laser field and betatron oscillations, the latter one not specified in the numerical simulations. Secondly this discrepancy may be due to the stochastic processes, which are absent in the analytical model.

It should be noted that the model \eqref{eqq4}\eqref{eqq5}\eqref{eq7} (paraxial approximation) is correct despite its deviation at low energies from the more accurate model \eqref{eqq4}\eqref{eqq5}\eqref{eq6} (see Fig.\ref{fig2}, orange and blue curves respectively). This is due to the phase portrait topology being determined by the singular points of the system \eqref{eq15} \eqref{eq16}, with $\gamma_{{cr}_2} \approx 5$ for $I_0 \approx 1$ at all plasma channel parameters considered (see Fig.\ref{fig3}). For this $\gamma $ values two models match well.

Another important difference between these models is that \eqref{eq6} (see Fig.\ref{fig2}, blue curve) in general has a range of forbidden $\gamma$ values (indicated in red in Fig.\ref{fig2}b). However for $I_0=1$, which is the value of interest, it vanishes, therefore only allowed values are present for the both models.

Finally, note that an equivalent to \eqref{eqq4}\eqref{eqq5}\eqref{eq7} system of equations can be constructed for the case of circularly polarized laser radiation. All of the calculations still hold, with some changes in  coefficients (for example energy gain will be different as in \eqref{eqq4} $\dfrac{1}{2}$ will be changed to $\dfrac{1}{\sqrt{2}}$).

\section{Conclusion}

We have studied in detail the analytically solvable model of electrons' direct laser acceleration (DLA). A 2D model with cylindrical hydrogen plasma channel given as static linear electric and magnetic fields and the laser given as a uniform plane wave was considered.

An electron energy gain was investigated through phase portraits $ \gamma(\Phi)$ \eqref{eqq4} \eqref{eqq5}. The changes in the topology and the pattern of bifurcation of these phase portraits have been analyzed. The DLA regime in which low-energy electrons are efficiently captured and accelerated has been found. This regime is determined by a phase portrait topology, which, in turn, depends on the value of the motion integral $I_0$  \eqref{eq3}, defined by the initial parameters of electrons.

When certain conditions, i.e. parameters of the plasma channel (absolute refractive index and ion concentration) \eqref{eq8}\eqref{eq9}\eqref{eq10} are imposed to the phase portraits, electrons with approximately zero initial energy are accelerated effectively (up to $\gamma\approx200$ for $\eta=0.99$, $n_{e_{out}}=0.07n_{cr}$) within a wide range of initial phases.

These results are supported by the numerical integration of equations of motion. Analytical model and numerical integration results match both in the range of initial parameters and the maximum energies gained by electrons. However, conditions \eqref{eq8} \eqref{eq9} \eqref{eq10}, of course, do not exactly meet, therefore there is a discrepancy in the initial phase area.

To conclude, developed simplified analytically solvable model, supported by the numerical integration of equation of motion, demonstrates the possibility of ionization injection into the plasma channel at a rather wide range of its parameters and initial phases.
Thus, this analytical model provides knowledge about the electron's motion in a plasma channel without numerical calculations and can form a basis for further study of electron injection in direct laser electron acceleration.

\begin{acknowledgments}
This work was supported by RSF Grant No. 21-79-10207. D.G. acknowledges the Foundation for Theoretical Research 'Basis' for financial support.

\end{acknowledgments}

\bibliographystyle{apsrev4-2}

redpajama_set_name: RedPajamaArXiv


text:
Joseph Jacobs
Joseph Jacobs (29 August 1854 - 30 January 1916) was an Australian born folklorist who published books on English and Celtic fairy tales.
1 English Fairy Tales (1890)
1.1 Preface to English Fairy Tales
1.2 Whittington and his Cat
1.3 The Story of the Three Little Pigs
1.4 The Story of the Three Bears
1.5 Catskin
1.6 Henny-Penny
1.7 Jack and the Beanstalk
1.8 Molly Whuppie
2 More English Fairy Tales (1894)
2.1 Pied Piper
2.2 The Three Wishes
English Fairy Tales (1890)[edit]
Preface to English Fairy Tales[edit]
Who says that English folk have no fairy-tales of their own?
Whittington and his Cat[edit]
Turn again Whittington,
Thrice Mayor of London
(said by the bells of London)
The Story of the Three Little Pigs[edit]
Little pig, little pig, let me come in.
To which the pig answered: Not by the hair of my chinny chin chin.
The wolf answered to that, Then I'll huff and I'll puff and I'll blow the house down.
Well, he [the wolf] huffed, and he puffed, and he puffed, and he puffed and he puffed and huffed; but he could not get the house down.
When the pig saw what he [the wolf] was about, he hung on a pot full of water, and made a blazing fire...and in fell the wolf...
The Story of the Three Bears[edit]
Out the Old Woman jumped (of the window). And whether she broke her neck in the fall; or ran into the wood and was lost there...or taken up by a constable to the House of Correction for the vagrant she was I cannot tell. But the Three Bears never saw anything more of her.
(note Goldilocks doesn't feature in this particular version of the story).
Catskin[edit]
Kind sir, if the truth I must tell,
At the sign of Basin of Water I dwell.
said by Princess Catskin
Henny-Penny[edit]
The sky is a-going to fall, I must go and tell the King.
said by Henny-Penny, similar to the words said by Chicken Little
Jack and the Beanstalk[edit]
There once was upon a time a poor widow who had an only son Jack, and a cow called Milky-White.
You don't know what these beans are, said the man [that Jack meets]. If you plant them overnight, by morning they grew right up to the sky.
My man is an ogre and there is nothing he likes better than boys broiled on toast.
Fee-fi-fo-fum,
I smell the blood of an Englishman,
Be he alive or be he dead
I'll have his bones to grind my bread.
(said by the ogre or giant. Now rendered as I'll grind his bones to make my bread.)
But the Harp called out quite loud: Master! Master!
Molly Whuppie[edit]
Fee, fi, fo, fum
I smell the blood of some earthly one.
(said by a giant, see Jack and the Beanstalk above.)
Woe worth you, Molly Whuppie! never you come again
Twice yet, carle, quoth she, I'll come to Spain.
More English Fairy Tales (1894)[edit]
Pied Piper[edit]
For out of every hole the rats came tumbling.
The Three Wishes[edit]
...he must need wish in a hurry; and wish he did, that the black pudding may come off his nose.
(said by Princess Catskin).
Encyclopedic article on Joseph Jacobs at Wikipedia
Works related to Author:Joseph Jacobs at Wikisource
Media related to Joseph Jacobs at Wikimedia Commons
Retrieved from "https://en.wikiquote.org/w/index.php?title=Joseph_Jacobs&oldid=2656589"
Historians from the United States
People from Sydney
Immigrants to the United States
Jews from the United Kingdom


Wesley LifeForce Networks promote suicide prevention in a wide variety of community settings throughout Australia, from urban centres, to remote Aboriginal communities.
By bringing together key members of the community who are dedicated to suicide prevention, Wesley LifeForce supports community members to take ownership of the issue and work towards real solutions to address the problem of suicide in their region.
Wesley LifeForce networks are coordinated nationally and align to best practice standards. Utilising the networks methodology, endorsed by the Australian Institute of Suicide Research and Prevention (AISRAP), potential network locations are identified in areas where there is a high rate and/or high incidence of suicide.
The Wesley LifeForce Community Hub is an online resource centre designed to assist our suicide prevention networks in operating effectively and learning from each other.
The community hub is available to all Wesley LifeForce member and affiliate networks, and enables them to tap into expertise where and when they need to.


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Nauhatta (also pronounced Nowhatta) is a large village in Nauhatta Block in Saharsa District of Bihar state, India. It belongs to Kosi Division . It is located 20 km towards North from District headquarters Saharsa. 165 km from State capital Patna. It comes under Mahisi constituency. The village had a population of 25,347 of which 13,124 were male while 12,223 were females as per Population Census 2011.

Language, area and population
The spoken languages of this village are Hindi, Urdu and Maithili. New generation uses English Language also.
Nauhatta village has lower literacy rate compared to Bihar. In 2011, literacy rate of Nauhatta village was 49.62% compared to 61.80% of Bihar. In Nauhatta Male literacy stands at 60.06% while female literacy rate was 38.27%.

It is hot in summer. Nauhatta summer highest day temperature is in between 27 °C to 44 °C .
Average temperatures of January is 16 °C, February is 20 °C, March is 27 °C, April is 31 °C, May is 33 °C .

The population is reached by 26000 approx now. Schedule Caste (SC) constitutes 14.50% while Schedule Tribe (ST) were 1.50% of total population in Nauhatta village of Saharsa district. The Nauhatta village population of children with age 0-6 is 4815 which makes up 19.00% of total population of village. Average Sex Ratio of Nauhatta village is 931 which is higher than Bihar state average of 918. Child Sex Ratio for the Nauhatta as per census is 986, higher than Bihar average of 935.

Economy
In Nauhatta village out of total population, 9205 were engaged in work activities. 47.52% of workers describe their work as Main Work (Employment or Earning more than 6 Months) while 52.48% were involved in Marginal activity providing livelihood for less than 6 months. Of 9205 workers engaged in Main Work, 877 were cultivators (owner or co-owner) while 2461 were agricultural labourers.

Society, religion, and culture
The village population consists of many different religious people.
The entire village is so well located but this area has also much been affected by the flood of Koshi river. Even in the worst flood of 1984 the main village was not safe and the water entered in the village.

How to reach Nauhatta

 By Rail
There is no railway station near to Nauhatta Block in less than 10km.  Saharsa Jn Railway Station (in Saharsa city) is the major railway station of the Kosi Division, Karukhirharnagar Halt Rail Way Station (near to Saharsa) are the Railway stations reachable from nearby towns.

 By Road
Saharsa is the nearest city to Nauhatta. It is connected with road.

References

Villages in Saharsa district

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text:
import React from 'react';

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export default controllerUnit;


text:
NewsLocalCyprus and Greece are pillars of stability in the region, Greek Defence...
Cyprus and Greece are pillars of stability in the region, Greek Defence Minister says
Greek Defence Minister Panos Kammenos said on Monday that thanks to the sacrifices made by Greek Cypriots and the people of Greece, Cyprus and Greece are no longer countries causing crises but rather countries of stability in the wider Mediterranean region.
In a statement after a military parade in Nicosia, to mark the anniversary of Cyprus' Independence Day, Kammenos who represented the Greek government at the celebrations, stressed that "Greece is here, standing by Cyprus."
Kammenos said that the hard work by the two countries' military forces, the two ministries of defence and the two governments has led to bilateral and trilateral agreements which have highlighted the role of Greece and Cyprus as "stability pillars", while both countries have become the Mediterranean's new energy hub.
The Greek minister said that "we will truly celebrate when Cyprus is liberated, when Cyprus is reunified" and pledged to continue to struggle for Cyprus' final liberation, stressing that Greek Cypriots should be able to feel safe.
Cyprus has been divided since 1974 when Turkey invaded and occupied its northern third.
Numerous UN-backed negotiations, aiming at reuniting the island under a federal roof, have failed to yield results. The latest talks under UN aegis took place in the summer of 2017 at the Swiss resort of Crans-Montana.
(Cyprus News Agency)
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Drone shows Greek lagoon full of thousands of dead fish from snowstorm


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text:
Remark Holdings Receives GDPR Certification for its AI Platform and Family of Thermal Detection Products
General Data Protection Requirements is the European Standard for Protection of Consumer Privacy
Remark Holdings, Inc.
LAS VEGAS, Sept. 22, 2020 /PRNewswire/ -- Remark Holdings, Inc. (NASDAQ: MARK), a diversified global technology company with leading artificial intelligence ("AI") solutions and digital media properties, today announced that its Smart AI Platform and line of thermal-detection products has received GDPR certification.
"From day one, we have built our platform to focus on privacy while providing the necessary tools to help our clients make informed decisions about their business. Receipt of certification of GDPR compliance for our line of AI and thermal-detection products opens up European markets and the opportunity for additional distribution partnerships," noted Kai-Shing Tao, Chairman and Chief Executive Officer of Remark Holdings, Inc.
To obtain GDPR compliance, a product needs to fulfill the following GDPR Requirements:
Lawfulness, fairness and transparency
Purpose limitation
Data minimization
Storage limitation
Integrity and confidentiality (security)
Remark's AI-powered Bio-Safety Thermal Kit is an all-inclusive solution that allows for fast, touch-free scanning of multiple persons (as many as 120 people per minute) as they enter through established access points. The system instantly and quietly alerts staff of any person with a skin temperature that suggests a higher-than-normal temperature, allowing site personnel to conduct a secondary temperature check.
Remark's R-Pad provides the thermal-detection functionality on a person-by-person basis, and it can be utilized for access control at individual access points as well as to detect the body temperatures of employee or customers, all while integrating directly with a customer's database.
Additional information can be obtained by contacting the company at: [email protected] or www.remarkthermal.com.
About Remark Holdings, Inc.
Remark Holdings, Inc. (NASDAQ: MARK) delivers an integrated suite of AI solutions that enable businesses and organizations to solve problems, reduce risk and deliver positive outcomes. The company's easy-to-install AI products are being rolled out in a wide range of applications within the retail, financial, public safety and workplace arenas. The company also owns and operates digital media properties that deliver relevant, dynamic content and ecommerce solutions. The company is headquartered in Las Vegas, Nevada, with additional operations in Los Angeles, California and in Beijing, Shanghai, Chengdu and Hangzhou, China. For more information, please visit the company's website at www.remarkholdings.com.
This press release may contain forward-looking statements, including information relating to future events, future financial performance, strategies, expectations, competitive environment and regulation. Words such as "may," "should," "could," "would," "predicts," "potential," "continue," "expects," "anticipates," "future," "intends," "plans," "believes," "estimates," and similar expressions, as well as statements in future tense, identify forward-looking statements. These statements involve known and unknown risks, uncertainties and other factors, including those discussed in Part I, Item 1A. Risk Factors in Remark Holdings' Annual Report on Form 10-K and Remark Holdings' other filings with the SEC. Any forward-looking statements reflect Remark Holdings' current views with respect to future events, are based on assumptions and are subject to risks and uncertainties. Given such uncertainties, you should not place undue reliance on any forward-looking statements, which represent Remark Holdings' estimates and assumptions only as of the date hereof. Except as required by law, Remark Holdings undertakes no obligation to update or revise publicly any forward-looking statements after the date hereof, whether as a result of new information, future events or otherwise.
E. Brian Harvey
Director of Capital Markets and Investor Relations
Fay Tian
Vice President of Investor Relations
SOURCE Remark Holdings, Inc.
http://www.remarkholdings.com
Remark Holdings, Inc. partners with AAEON to simplify the delivery of AI-driven video analytics for a complex world
Remark Holdings Successfully Achieves Compliance with Nasdaq Listing Requirements


Learn more about egg freezing at an educational event that is informational, casual, and free to attend!
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I'm Michel van Heest, an Interaction and UX design-student, productivity-nerd, craftbeer-geek and occasional front-end-enthousiast.
I'm currently following an design-education at the Rotterdam University of Applied Sciences, I learn fast and I'm extremely motivated to learn new things about design and technology.
Because I'm driven to expand my knowledge; learning about Interaction Design, testing, research and front-end development are actualy my biggest hobbies. I love to tinker with it in my free time.
I'm also slightly addicted to discovering and using a variety of productivity tools and theories and optimizing my workflow or helping other optimizing theirs.
Ow, and I brew my own craft beer, can enjoy one bottle for three hours and don't stop talking when you ask me about it (I'm a nerd, guilty as charged).
I'm currently working as a student assistant at the Rotterdam University teaching first-year students to work with Sketch app.
Prior I used to work at Awkward as a product design intern, at the advertising agency Maerke and in IT management at one of the larger pharmacy-webshop in the Netherlands.
Users notice when your product doesn't have a good design or user experience. But when your product is actually well designed and a designer has thought and worked countless of hours on the user experience, the user will not start thinking about how good and how user friendly everything is because they actually didn't notice the design.
I want to become a master in making experiences so frictionless, users don't actually notice it when I touched their product. Building (and shipping) a product is awesome, but I think the user is actually the 'most important bit' of the process.
My proudest moment in trying to make 'frictionless experiences' was when I launched my first real big side-project, Shortcuts.design.
Quickly, the product went viral in the design-community, something I quite frankly never expected. The website was on top at Producthunt and DesignerNews and was featured on the website or Twitter of companies like CreativeBloq, Sidebar, T3N and InVision, to name a few.
Due the attention, Shortcuts.design gathered a big group of users which made it possible for me to start making the site not only for the community but also by the community: users first.


text:
Metal fans seek solace in Patrik Bergh's brilliant new short
Quest for Fire, a funny new film from the 76 Ltd director centres on a support group for maligned heavy metal fans.
by Danny Edwards on 29th April 2019
Quest For Fire
Production Company 76 Ltd
Director Patrik Bergh
Producer Russell Curtis
1st Assistant Director Jacqueline Moore / (Assistant Director)
DP Callan Green
Long black hair, even longer black trench coat and a propensity to stick their tongues out while playing air guitar; we all know what heavy metal fans are like, don't we?
Well, in Patrik Bergh's fantastic new short film, Quest for Fire, those fans are given a chance to bemoan their musical standing in a safe and supportive environment. Here Bergh [pictured below] , explains the genesis of the film and explains why metal fans are misunderstood.
The title is also a metaphor for the fire that burns within all the characters, the true passion for metal!
Above: 76 Ltd director Patrik Bergh
Where did the idea for Quest of Fire come from?
A very good friend of mine is a complete metal nut. He was telling me how much his wife hates his passion for heavy metal so much that he now only listens to it when she's not around. It's like a drug for him that he can't live without and he hides it from his own wife.
I think that this love for music, a genre that so many people despise or don't understand, is fascinating. I immediately pictured this self-help group for metal heads and wrote down a bunch of ideas the next day. I then edited the script down to two main stories.
Is metal music something you have a love for?
As a teenager, absolutely, yes. I still listen to it occasionally and have a huge fascination in the culture of heavy metal and its fan base. There's nothing quite like it.
Do you think metal heads are an outsider tribe and is that what attracted you to them?
Absolutely. Most people just don't get metal and can even get pretty offended by it. I remember being at a dinner party and everyone was being DJ on Spotify and playing all kinds of pop. I decided to mix it up a bit and put on this heavy metal track (Take Hold of the Flame by Queensryche) and everyone at the party got seriously put off and angry.
Being a true metal fan demands dedication. For genuine fans it's extremely real, not an act or a trend. They are passionate about the music and incredibly loyal to the bands. More so than most genres.
Being a true metal fan demands dedication. For genuine fans it's extremely real, not an act or a trend.
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Can you tell us a bit about the casting; the two guys who relay their stories are great?
The casting process was long and difficult! To me, it was so important that the performances felt genuine but not morose. There had to be an element of humour about it too.
Some actors auditioned for the first role, and it was so heavy and depressing. And then others came and totally hammed it up. Finding the balance somewhere in between was extremely important to me. It had to be funny, yet heartfelt. We must be able to laugh at these characters but also feel for them.
At first, we saw a lot of people who were actual metal fans but none of them were actually good enough. And in the end, I realised that was irrelevant. Instead it was about finding two great actors who we could feel empathy with.
When writing the script, I always had in mind an image of starting close on a face that looked tired and worn. A face that when we looked at it we would from the get-go be thinking 'what's up with him?!'"
The end song is I Wanna Rock, and was a huge hit in the mid 80s. It's a pretty cheesy song, but the lyrics are perfect for the film and self-explanatory.
Why did you choose Quest for Fire as the title?
Quest for Fire is an Iron Maiden song the main character plays at his kids' school disco. The title is also a metaphor for the fire that burns within all the characters, the true passion for metal!
I'm afraid I don't know what the lyrics sung at the end are (it doesn't seem to be Quest for Fire, according to Google!); what are they and why were they chosen?
The end song is I Wanna Rock by Twisted Sisters and was a huge hit in the mid 80s. It's a pretty cheesy song to be honest, but the lyrics are perfect for the film and self-explanatory.
It's an anthem against everyone who doesn't like rock music basically! "Tell me not to play, Well, all I got to say when you tell me not to play I say No! No! No! No! So, if you ask me why I like the way I play it There's only one thing I can say to you, I wanna rock."
Also, was it hard to get clearance for them?
We contacted the record label directly for clearance of I Wanna Rock. They wanted to see a copy of the film and then charged us the going rate for short films.
When did you shoot the film?
We shot the film last summer during the hottest day of the year and, let me tell you, spandex trousers are hot! Our 'spandex' actor sat in his underwear when we shot his close-ups!
The Great Guns director speaks to Jamie Madge about bringing the space-bound ninja samurai action game to the screen with his animation debut.
The director talks us through helming an intense 3D experience for The Viking Planet Centre, Oslo with RSA Films.
Step into a world of peacock chairs, leopard print and saxophones as Uncommon and Daniel Warwick reveal how they made the Hot Praise Hotline.
61 strangers from across the globe are united by tattoos in &Co's powerful social campaign.