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In her remarkable photo essay “From the Shadows to the Light,” the French photographer Nadège Mazars has emulated the chiaroscuro of the Italian painter Caravaggio to evoke the transition that is under way in Colombia following fiftytwo years of civil war. After the signing of a historic peace agreement with the government late last year, the country’s seventhousandodd Marxist FARC fighters recently began moving into a series of camps. There, as I reported in this week’s magazine, they are in the process of laying down their arms in preparation for being “reincorporated” into Colombian society.
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After almost a decade of research, Google's autonomous car project is close to becoming a real service. Now known as Waymo, the Alphabet Inc. selfdriving car unit is letting residents of Phoenix sign up to use its vehicles, a major step toward commercializing a technology that could one day upend transportation. This is going to change our society a lot quicker than people seem to think.
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AT&T announced plans to deliver what it's calling the "5G Evolution" network to more than 20 markets by the end of the year. While the company is "using some wordsmithing to deliver to you faster internet speeds," it's important to note that this is not actually a real 5G network. Yahoo reports: 5G still has years of development and testing before it will be rolled out across the U.S. So don't let AT&T's use of "5G" make you think that the nextgeneration wireless standard has arrived. In reality, the 5G AT&T is talking about is a bumpedup version of its 4G LTE to help it bridge the gap until the real 5G, with its ultrafast speeds and better bandwidth, is rolled out. It's also important to note that AT&T won't offer its 5G Evolution technology to all of its customers initially. In fact, it's currently only available in Austin, TX, and the company plans to extend it to Atlanta, Boston, Chicago, Los Angeles, and other big markets in the coming months. If you're in a sma
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The international project of flattering Ivanka Trump—which some of the world’s most notable women, from Angela Merkel, the Chancellor of Germany, to Queen Máxima, of the Netherlands, engaged in at a panel discussion during the W20 conference, in Berlin, this week—does not always run smoothly. There was, first, the achingly obvious oddity of deciding that Trump, whose experience on the public stage largely consists of marketing her clothing and jewelry lines, and her efforts to get her father, Donald Trump, elected, was qualified to sit between Christine Lagarde, the head of the International Monetary Fund, and Chrystia Freeland, the Foreign Minister of Canada. That was quickly followed by the dispiriting thought that Trump might actually have as much power over people’s lives as the other women, through the influence that she supposedly wields over her father. Why else would the head of the World Bank, Jim Yong Kim, have coauthored an oped in the Financial Times with her, on th
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According to Reuters, "Tesla executive Klaus Grohmann was ousted last month after a clash with CEO Elon Musk over the strategy of Grohmann's firm, which Tesla had acquired in November." Grohmann Engineer's automation and engineering expertise is being relied upon by Tesla to help it increase production to 500,000 cars per year by 2018. From the report: Tesla planned to keep Grohmann on, and Grohmann wanted to stay, but the clash with Musk over how to treat existing clients resulted in his departure, the source said. Grohmann disagreed with Musk's demands to focus management attention on Tesla projects to the detriment of Grohmann Engineering's legacy clients, which included Tesla's direct Germanbased rivals Daimler and BMW, two sources familiar with the matter said. "I definitely did not depart because I had lost interest in working," Grohmann said, without elaborating. A Tesla spokesman, asked about Grohmann's departure, praised him for building an "incredible company" and said: "Par
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An anonymous reader quotes a report from Recode: The company has recently held discussions with payments industry partners about introducing its own Venmo competitor, according to multiple sources familiar with the talks. The service would allow iPhone owners to send money digitally to other iPhone owners, these people said. One source familiar with the plans told Recode they expect the company to announce the new service later this year. Another cautioned that an announcement and launch date may not yet be set. The new Apple product would compete with offerings from big U.S. banks as well as PayPal, its millennialpopular subsidiary Venmo, as well as Square Cash in the increasingly competitive world of digital moneytransfers. Apple has also recently held discussions with Visa about creating its own prepaid cards that would run on the Visa debit network and which would be tied to the new peertopeer service, sources told Recode. People would be able to use the Apple cards to spend m
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Reader Krystalo writes: Google today announced the second step in its plan to mark all HTTP sites as nonsecure in Chrome. Starting in October 2017, Chrome will mark HTTP sites with entered data and HTTP sites in Incognito mode as nonsecure. With the release of Chrome 56 in January 2017, Google's browser started marking HTTP pages that collect passwords or credit cards as "Not Secure" in the address bar. Since then, Google has seen a 23 percent reduction in the fraction of navigations to HTTP pages with password or credit card forms on Chrome for desktop. Chrome 62 (we're currently on Chrome 58) will take this to the next level.
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With the release of Windows 10, we simplified the servicing process by moving to cumulative updates, where each update released contains all the new fixes for that month, as well as all the older fixes from previous months. Today, most organizations deploy these cumulative updates when they are released on the second Tuesday of every month, also called "Update Tuesday." Because these updates contain new security fixes, they are considered "Security Updates" in Windows Server Update Services (WSUS) and System Center Configuration Manager. Based on feedback from customers, we are making some adjustments to the updates that we are releasing for Windows 10, version 1703 (also known as the "Creators Update"). With these changes, we will routinely offer one (or sometimes more than one) additional update each month. These additional cumulative updates will contain only new nonsecurity updates, so they will be considered "Updates" in WSUS and Configuration Manager.
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Midway through my conversation with the poet Morgan Parker, she suggested a diversion: “Do you want to get tattoos?” Parker, who is twentynine and grew up hanging around skate parks in Southern California, had fourteen already. She got the first—an apple on her right wrist—when she was a nineteenyearold undergraduate, at Columbia University. In 2012, when she completed her poetry M.F.A., at New York University, she had the Blue Note Records logo inked on her thigh. Last year, after she published her first book and got a day job working as an editor at Amazon, she got “reparations” tattooed across her wrist in an elegant, galloping script; she likes the disconnect between the difficulty of the word, at least as most people perceive it, and the prettiness of the font. The tattoos with text, she explained, are “things that I need to read and see every day. They become mantras.” There are bits of poetry by Langston Hughes and Lucille Clifton on her right and left forearms, respectively,
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randomErr writes: David Foster, who joined Alphabet Inc.'s Google in October as part of its aggressive hardware effort, has left the company. As the vice president of hardware product development he worked on the launch of the Pixel smartphone and Home speaker. Both of which are competitors to the Amazon Echo, Foster's previous employer. Google will not comment on why he is leaving.
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Google isn't planning to rid fake news from its search results  but it's trying to purge it from the top. The Alphabet Inc. company is making a rare, sweeping change to the algorithm behind its powerful search engine to demote misleading, false and offensive articles online. Google is also setting new rules encouraging its "raters"  the 10,000plus staff that assess search results  to flag web pages that host hoaxes, conspiracy theories and what the company calls "lowquality" content. Good  but also possibly incredibly dangerous.
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Employees of Facebook and Google were the victims of an elaborate $100 million phishing attack, according to a new report on Fortune, which further adds that the employees were tricked into sending money to overseas bank accounts. From the report: In 2013, a 40something Lithuanian named Evaldas Rimasauskas allegedly hatched an elaborate scheme to defraud U.S. tech companies. According to the Justice Department, he forged email addresses, invoices, and corporate stamps in order to impersonate a large Asianbased manufacturer with whom the tech firms regularly did business. The point was to trick companies into paying for computer supplies. The scheme worked. Over a twoyear span, the corporate imposter convinced accounting departments at the two tech companies to make transfers worth tens of millions of dollars. By the time the firms figured out what was going on, Rimasauskas had coaxed out over $100 million in payments, which he promptly stashed in bank accounts across Eastern Europe.
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An anonymous reader quotes a report from The Guardian: A revolutionary blood test has been shown to diagnose the recurrence of cancer up to a year in advance of conventional scans in a major lung cancer trial. The test, known as a liquid biopsy, could buy crucial time for doctors by indicating that cancer is growing in the body when tumors are not yet detectable on CT scans and long before the patient becomes aware of physical symptoms. It works by detecting freefloating mutated DNA, released into the bloodstream by dying cancer cells. In the trial of 100 lung cancer patients, scientists saw precipitous rises in tumor DNA in the blood of patients who would go on to relapse months, or even a year, later. In the latest trial, reported in the journal Nature, 100 patients with nonsmall cell lung cancer were followed from diagnosis through surgery and chemotherapy, having blood tests every six to eight weeks. By analyzing the patchwork of genetic faults in cells across each tumor, scienti
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Much like IT guys, every programmer has a horror story about the extreme work environments that forced them to hack together things. But as ArsTechnica points out, not many of them can beat the keyboardfree coding environment that Masahiro Sakurai apparently used to create the first Kirby's Dream Land. From the story: The tidbit comes from a talk Sakurai gave ahead of a Japanese orchestral performance celebrating the 25th anniversary of the original Game Boy release of Kirby's Dream Land in 1992. Sakurai recalled how HAL Laboratory was using a Twin Famicom as a development kit at the time. Trying to program on the hardware, which combined a cartridgebased Famicom and the diskbased Famicom Disk System, was "like using a lunchbox to make lunch," Sakurai said. As if the limited power wasn't bad enough, Sakurai revealed that the Twin Famicom testbed they were using "didn't even have keyboard support, meaning values had to be input using a trackball and an onscreen keyboard."
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Facebook is pressing its enforcement against what it calls "information operations"  bad actors who use the platform to spread fake news and false propaganda. From a report: The company, which published a report on the subject today, defines these operations as governmentled campaigns  or those from organized "nonstate actors"  to promote lies, sow confusion and chaos among opposing political groups, and destabilize movements in other countries. The goal of these operations, the report says, is to manipulate public opinion and serve geopolitical ends. The actions go beyond the posting of fake news stories. The 13page report specifies that fake news can be motivated by a number of incentives, but that it becomes part of a larger information operation when its coupled with other tactics and end goals. Facebook says these include friend requests sent under false names to glean more information about the personal networks of spying targets and hacking targets, the boosting of fals
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The IT workers from the University of California's San Francisco campus who were replaced by an offshore outsourcing firm late last year intend to file a lawsuit challenging their dismissal. "It will allege that the tech workers at the university's San Francisco campus were victims of age and national origin discrimination," reports Computerworld. From the report: The IT employees lost their jobs in February after the university hired Indiabased IT services firm HCL. Approximately 50 fulltime university employees lost their jobs, but another 30 contractor positions were cut as well. "To take a workforce that is overwhelmingly over the age of 40 and replace them with folks who are mainly in their 20s  early 20s, in fact  we think is age discrimination," said the IT employees' attorney, Randall Strauss, of Gwilliam Ivary Chiosso Cavalli & Brewer. The national origin discrimination claim is the result of taking a workforce "that reflects the diversity of California" and is summa
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In the spring of 1988, four London plane trees were mysteriously cut down in Temple Square, at the corner of Schermerhorn Street and Flatbush Avenue, in Brooklyn. Witnesses reported seeing a crew of about ten men arrive in an orange truck; when they left, they took the illicit timber with them. The local rumor was that a group of neighborhood shop owners had arranged for the trees’ removal, hoping to make their businesses more visible. Not long afterward, Henry J. Stern, the commissioner of the New York City Department of Parks and Recreation, organized a memorial service. He wore a black armband for the occasion and, accompanied by a recording of Verdi’s Requiem, delivered a brief eulogy. “This is arborcide in the first degree,” Stern said. “The loss of a tree is not the loss of a person, but plant life nonetheless deserves our respect. We are highly resolved that these trees shall not have died in vain.”
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In the fourth episode of “The Handmaid’s Tale,” the gripping new Hulu adaption of Margaret Atwood’s novel, Offred, our narrator and heroine, goes to the gynecologist. She lies on an examining table, her lower body, and the male doctor poking at it, concealed from her view by a gauzy white curtain. Offred, played by Elisabeth Moss, is a handmaid in Gilead, the brutally repressive patriarchy that has subsumed the place formerly known as the United States, and a handmaid’s job is to reproduce; she is “a womb on two legs,” solemnly raped once a month by her Commander, Fred (Joseph Fiennes), as she lies rigid in the lap of his “barren” wife. At least the official explanation is that she’s barren. The nation’s plummeting birth rates are blamed on its women. Offred’s doctor has a different idea. The Commander is probably sterile, he says. Most highranking men in Gilead are. “Sterile. That’s a forbidden word,” Offred thinks. For a woman, to speak it could mean death.
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The US space industry is prodding the US government into refreshing its outdated laws on commercial activity beyond earth: scare it with talk of Chinese galactic domination. A report adds: At a Senate hearing on the space industry this week, companies that build rockets and space habitats and manufacture electronic goods in space spoke about a standard laundry list of complaints, from regulatory burdens to fears of subsidized competitors. But their message was wrapped in patriotic concerns about China's growing capacity for space action. These companies are eager for the US government to allow and invest in commercial activities in orbit and around the moon. Many think the laws governing action in space, and particularly the UN Space Treaty, need refreshing for an age when private companies are close to matching the space capacity of sovereign nations. The last major change was a law on asteroid mining passed in 2015.
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The Linux kernel is highly scalable but, while it runs nicely on the world's largest computers, it is not an entirely comfortable fit on the smallest. The difficulties involved in running Linux on machines with 1MB or less of memory have left an opening for other operating systems, such as Zephyr, with lower memory needs. Some developers have not given up on scaling Linux to the smallest computers, but the approaches they have to take have always been a bit of a hard sell with the rest of the development community. Nicolas Pitre's minitty patch set is a case in point.
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Tor 0.3.0.6, the first stable release of the Tor 0.3.0 series, is available. "With the 0.3.0 series, clients and relays now use Ed25519 keys to authenticate their link connections to relays, rather than the old RSA1024 keys that they used before. (Circuit crypto has been Curve25519authenticated since 0.2.4.8alpha.) We have also replaced the guard selection and replacement algorithm to behave more robustly in the presence of unreliable networks, and to resist guard capture attacks."
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Nomx, a startup that offers an email client by the same name, bills itself as the maker of the "world's most secure email service." The startup goes on to suggest that "everything else is insecure." So it was only a matter of time before someone decided to spend some time on assessing how valid Nomx's claims are. Very misleading, it turns out. From a report on Motherboard: Nomx sells a $199 device that essentially helps you set up your own email server in an attempt to keep your emails away from mail exchange (or MX)  hence the brand name  servers, which the company claims to be inherently "vulnerable." Security researcher Scott Helme took apart the device and tried to figure out how it really works. According to his detailed blog post, what he found is that the box is actually just a Raspberry Pi with outdated software on it, and several bugs. So many, in fact, that Helme wrote Nomx's "code is riddled with bad examples of how to do things." The worst issue, Helme explained, is tha
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In this paper we consider all orientationpreserving $\mathbb{Z}_{p^2}$actions on 3dimensional handlebodies $V_g$ of genus $g>0$ for $p$ an odd prime. To do so, we examine particular graphs of groups $(\Gamma($v$),\mathbf{G(v)})$ in canonical form for some 5tuple v $=(r,s,t,m,n)$ with $r+s+t+m>0$. These graphs of groups correspond to the handlebody orbifolds $V(\Gamma($v$),{\mathbf{G(v)}})$ that are homeomorphic to the quotient spaces $V_g/\mathbb{Z}_{p^2}$ of genus less than or equal to $g$. This algebraic characterization is used to enumerate the total number of $\mathbb{Z}_{p^2}$actions on such handlebodies, up to equivalence.
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When considering binary strings, it's natural to wonder how many distinct subsequences might exist in a given string. Given that there is an existing algorithm which provides a straightforward way to compute the number of distinct subsequences in a fixed string, we might next be interested in the expected number of distinct subsequences in random strings. This expected value is already known for random binary strings where each letter in the string is, independently, equally likely to be a 1 or a 0. We generalize this result to random strings where the letter 1 appears independently with probability $\alpha \in [0,1]$. Also, we make some progress in the case of random strings from an arbitrary alphabet as well as when the string is generated by a twostate Markov chain.
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We study collinear relative equilibria of the planar fourvortex problem where three of the four vortex strengths are identical. The $S_3$ invariance obtained from the equality of vorticities is used to reduce the defining equations and organize the solutions into two distinct groups based on the ordering of the vortices along the line. The number and type of solutions are given, along with a discussion of the bifurcations that occur. The linear stability of all solutions is investigated rigorously and stable solutions are found to exist for cases where the vorticities have mixed signs. We employ a combination of analysis and computational algebraic geometry to prove our results.
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The celebrated GKYP is widely used in integerorder control system. However, when it comes to the fractional order system, there exists no such tool to solve problems. This paper prove the FGKYP which can be used in the analysis of problems in fractional order system. The $H_\infty$ and $L_\infty$ of fractional order system are analysed based on the FGKYP.
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We give a survey of elliptic hypergeometric functions associated with root systems, comprised of three main parts. The first two form in essence an annotated table of the main evaluation and transformation formulas for elliptic hypergeometric integeral and series on root systems. The third and final part gives an introduction to Rains' elliptic MacdonaldKoornwinder theory (in part also developed by Coskun and Gustafson).
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The Boutet de Monvel calculus of pseudodifferential boundary operators is generalised to the full scales of Besov and TriebelLizorkin spaces (though with finite integral exponents for the latter). The continuity and Fredholm properties proved here extend those previously obtained by Franke and Grubb, and the results on range complements of surjectively elliptic Green operators improve the earlier known, even for the classical spaces with $1<p<\infty$. The symbol classes treated are the uniformly estimated ones. Some precisions are given for the general definitions of trace and singular Green operators of class 0.
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This article extends the author's past work [Inv. Probl. Imaging, 10:2 (2016), 433459] to attenuated Xray transforms, where the attenuation is complexvalued and only depends on position. We give a positive and constructive answer to the attenuated tensor tomography problem on the Euclidean unit disc in fanbeam coordinates. For a tensor of arbitrary order, we propose an equivalent tensor of the same order which can be uniquely and stably reconstructed from its attenuated transform, as well as an explicit and efficient procedure to do so.
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The theoretical description of nonrenewal stochastic systems is a challenge. Analytical results are often not available or can only be obtained under strong conditions, limiting their applicability. Also, numerical results have mostly been obtained by adhoc MonteCarlo simulations, which are usually computationally expensive when a high degree of accuracy is needed. To gain quantitative insight into these systems under general conditions, we here introduce a numerical iterated firstpassage time approach based on solving the timedependent FokkerPlanck equation (FPE) to describe the statistics of nonrenewal stochastic systems. We illustrate the approach using spiketriggered neuronal adaptation in the leaky and perfect integrateandfire model, respectively. The transition to stationarity of firstpassage time moments and their sequential correlations occur on a nontrivial timescale that depends on all system parameters. Surprisingly this is so for both single exponential and sca
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This article is devoted to a study of flat orbifold vector bundles. We construct a bijection between the isomorphic classes of proper flat orbifold vector bundles and the equivalence classes of representations of the orbifold fundamental groups of base orbifolds. We establish a BismutZhang like anomaly formula for the RaySinger metric on the determine line of the cohomology of a compact orbifold with coefficients in an orbifold flat vector bundle. We show that the analytic torsion of an acyclic unitary flat orbifold vector bundle is equal to the value at zero of a dynamical zeta function when the underlying orbifold is a compact locally symmetric space of the reductive type, which extends one of the results obtained by the first author for compact locally symmetric manifolds.
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Let $\mathcal{L}$ be a finite distributive lattice and $K[\mathcal{L}]=K[x_\alpha: \alpha \in \mathcal{L}]$ be the polynomial ring over $K$ and $I_{\mathcal{L}}=\langle x_\alpha x_\beta x_{\alpha\vee \beta} x_{\alpha\wedge\beta} : \alpha \nsim \beta,\alpha,\beta \in {\mathcal{L}} \rangle$ be the ideal of $K[\mathcal{L}]$. In this article we describe the first syzygy of Hibi ring $R[\mathcal{L}]=K[\mathcal{L}]/I_{\mathcal{L}}$, for a distributive lattice. We also derive an exact formula for the first betti number of a planar distributive lattice.
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Given a graph $G$, we would like to find (if it exists) the largest induced subgraph $H$ in which there are at least $k$ vertices realizing the maximum degree of $H$. This problem was first posed by Caro and Yuster. They proved, for example, that for every graph $G$ on $n$ vertices we can guarantee, for $k = 2$, such an induced subgraph $H$ by deleting at most $2\sqrt{n}$ vertices, but the question if $2\sqrt{n}$ is best possible remains open. Among the results obtained in this paper we prove that: 1. For every graph $G$ on $n \geq 4$ vertices we can delete at most $\lceil \frac{ 3 + \sqrt{ 8n 15}}{2 } \rceil$ vertices to get an induced subgraph $H$ with at least two vertices realizing $\Delta(H)$, and this bound is sharp, solving the problems left open by Caro and Yuster. 2.For every graph $G$ with maximum degree $\Delta \geq 1$ we can delete at most $\lceil \frac{ 3 + \sqrt{8\Delta +1}}{2 } \rceil$ vertices to get an induced subgraph $H$ with at least two vertices realizing $\Delt
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We introduce LipschitzKilling curvature (LKC) regression, a new method to produce $(1\alpha)$ thresholds for signal detection in random fields that does not require knowledge of the spatial correlation structure. The idea is to fit observed empirical Euler characteristics to the Gaussian kinematic formula via generalized least squares, which quickly and easily provides statistical estimates of the LKCs  complex topological quantities that can be extremely challenging to compute, both theoretically and numerically. With these estimates, we can then make use of a powerful parametric approximation via Euler characteristics for Gaussian random fields to generate accurate $(1\alpha)$ thresholds and $p$values. The main features of our proposed LKC regression method are easy implementation, conceptual simplicity, and facilitated diagnostics, which we demonstrate in a variety of simulations and applications.
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In the present paper we obtain sufficient conditions for the existence of equivalent martingale measures for L\'{e}vydriven moving averages and other nonMarkovian jump processes. The conditions that we obtain are, under mild assumptions, also necessary. For instance, this is the case for moving averages driven by an $\alpha$stable L\'{e}vy process with $\alpha \in (1,2]$. Our proofs rely on various techniques for showing the martingale property of stochastic exponentials.
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