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María de Jesús Estrada Juárez was applying for her green card and thought she was doing everything right。 Instead, she was arrested and deported to Mexico
Nitrogen-vacancy (NV) defect in diamond is a very promising tool for numerous sensing applications like magnetometry or thermometry. In this paper, we demonstrate a compact and convenient device for magnetic field imaging where a commercial single mode photonic crystal fibre is directly coupled to a commercial CVD ppm diamond. We managed to excite and detect efficiently the luminescence from an ensemble of NV centres and also to perform Electron Spin Resonance (ESR) experiments where the NV hyperfine structure is perfectly resolved under continuous excitation and measurement.
We digitize and analyze the near-universe of National Socialist German Workers' Party (NSDAP) membership records and link them to newly digitized population and industrial censuses. Four findings emerge. First, as the party expanded, its membership came to resemble the broader population more closely in occupational, demographic, and religious terms. Second, SS members remained distinctly different: younger, more educated, and more fanatical, as proxied by membership portraits. Third, within communities, coworkers, and families, early membership generated hysteresis, with subsequent entrants drawn from the same groups. Finally, local increases in party membership are associated with subsequent deportations of Germany's Jews.
International students (IntlS) in the US refer to foreign students who acquire student visas to study in the US, primarily in higher education. As IntlS arrive in the US, they face several challenges, such as adjusting to a new country and culture, securing housing remotely, and arranging finances for tuition and personal expenses. These experiences, coupled with recent events such as visa revocations and the cessation of new visas, compound IntlS' risk of being targeted by and falling victim to online scams. While prior work has investigated IntlS' security and privacy, as well as general end users' reactions to online scams, research on how IntlS are uniquely impacted by scams remains largely absent. To address this gap, we conduct a two-phase user study comprising surveys (n=48) and semi-structured interviews (n=9). We investigate IntlS' exposure and interactions with scams, post-exposure actions such as reporting, and their perceptions of the usefulness of existing prevention resources and the barriers to following prevention advice. We find that IntlS are often targeted by scams (e.g., attackers impersonating government officials) and fear legal implications or deportation, wh
This paper introduces a novel compliant mechanism combining lightweight and energy dissipation for aerial physical interaction. Weighting 400~g at take-off, the mechanism is actuated in the forward body direction, enabling precise position control for force interaction and various other aerial manipulation tasks. The robotic arm, structured as a closed-loop kinematic chain, employs two deported servomotors. Each joint is actuated with a single tendon for active motion control in compression of the arm at the end-effector. Its elasto-mechanical design reduces weight and provides flexibility, allowing passive-compliant interactions without impacting the motors' integrity. Notably, the arm's damping can be adjusted based on the proposed inner frictional bulges. Experimental applications showcase the aerial system performance in both free-flight and physical interaction. The presented work may open safer applications for \ac{MAV} in real environments subject to perturbations during interaction.
Seventy-five years ago, Bernardo Dessau passed away. He had been the sole professor of Physics at the University of Perugia for thirty years. With this brief contribution we intend to repay a debt of gratitude, first of all because his scientific merits were probably underestimated, having spent the first fifteen years of his career under the shadow of the great Augusto Righi in Bologna, where he also witnessed meetings with the young Marconi. He was then relegated to the Faculty of Medicine of Perugia, without a real laboratory, disregarded by the national scientific community and unable to move to better equipped locations. Nevertheless, he proved to be a gifted teacher and popularizer of science. He published a comprehensive three-volume physics textbook that was widely used in Italy and abroad. Despite becoming an Italian citizen in 1894, Dessau's German origins led to his suspension from service during World War I. Furthermore, his Jewish identity made him a target of Nazi-fascist antisemitism. He was dismissed from both the University of Perugia and from the Italian Society of Physics, of which he had been a member since its beginning, fortunately escaping deportation.
This paper evaluates the impact of the pandemic and enforcement at the US and Mexican borders on the emigration of Guatemalans during 2017-2020. During this period, the number of crossings from Guatemala fell by 10%, according to the Survey of Migration to the Southern Border of Mexico. Yet, there was a rise of nearly 30% in the number of emigration crossings of male adults travelling with their children. This new trend was partly driven by the recent reduction in the number of children deported from the US. For a one-point reduction in the number of children deported from the US to Guatemalan municipalities, there was an increase of nearly 14 in the number of crossings made by adult males leaving from Guatemala for Mexico; and nearly 0.5 additional crossings made by male adults travelling with their children. However, the surge of emigrants travelling with their children was also driven by the acute economic shock that Guatemala experienced during the pandemic. During this period, air pollution in the analysed Guatemalan municipalities fell by 4%, night light per capita fell by 15%, and homicide rates fell by 40%. Unlike in previous years, emigrants are fleeing poverty rather than
Robotic sensorimotor extensions (supernumerary limbs, prosthesis, handheld tools) are worn devices used to interact with the nearby environment, whether to assist the capabilities of impaired users or to enhance the dexterity of industrial operators. Despite numerous mechanical achievements, embedding these robotics devices remains critical due to their weight and discomfort. To emancipate from these mechanical constraints, we propose a new hybrid system using a virtually worn robotic arm in augmented-reality, and a real robotic manipulator servoed on such virtual representation. We aim at bringing an illusion of wearing a robotic system while its weight is fully deported, thinking that this approach could open new horizons for the study of wearable robotics without any intrinsic impairment of the human movement abilities.
One of the main issue in robotics is the lack of embedded computational power. Recently, state of the art algorithms providing a better understanding of the surroundings (Object detection, skeleton tracking, etc.) are requiring more and more computational power. The lack of embedded computational power is more significant in mass-produced robots because of the difficulties to follow the increasing computational requirements of state of the art algorithms. The integration of an additional GPU allows to overcome this lack of embedded computational power. We introduce in this paper a prototype of Pepper with an embedded GPU, but also with an additional 3D camera on the head of the robot and plugged to the late GPU. This prototype, called Adapted Pepper, was built for the European project called MuMMER (MultiModal Mall Entertainment Robot) in order to embed algorithms like OpenPose, YOLO or to process sensors information and, in all cases, avoid network dependency for deported computation.
Scientists at UC Santa Barbara have created a remarkable new material that works like a “rechargeable solar battery,” storing sunlight inside tiny molecules and releasing it later as heat — even long after the sun goes down。 Inspired by reversible changes found in DNA and photochromic sunglasses, the system captures solar energy without relying on
Astronomers using the James Webb Space Telescope have spotted something that shouldn’t exist—at least not so early in the universe。 A massive galaxy, formed less than 2 billion years after the Big Bang, appears to have no rotation at all, a trait usually seen only in much older, evolved galaxies。 This challenges current theories that young galaxies
NASA is testing a next-generation space computer chip that could give spacecraft the ability to operate far more independently in deep space。 The radiation-hardened processor is showing performance levels hundreds of times beyond current spaceflight computers while surviving punishing tests designed to mimic the harsh conditions of space。 The techn
NASA’s Curiosity rover had an unexpectedly stubborn Mars souvenir after drilling into a rock nicknamed “Atacama” — the entire chunk ripped loose from the ground and stayed stuck to the rover’s drill。 Engineers watched as Curiosity shook, vibrated, tilted, and spun the drill over several days in an effort to free the rock, while cameras captured the
A major obstacle may be standing in the way of the next generation of ultra-tiny computer chips。 Researchers discovered that many promising 2D materials lose their advantages because an invisible atomic-scale gap forms when they are combined with insulating layers。 That tiny gap weakens electronic performance and could prevent further miniaturizati
Physicists may have just cracked open a hidden side of the quantum world。 For decades, every known particle was thought to belong to one of two categories — bosons or fermions — but researchers have now shown that bizarre “in-between” particles called anyons could also exist in a one-dimensional system。 Even more exciting, these strange particles m
Astronomers using NASA’s James Webb Space Telescope have created the clearest map yet of the universe’s “cosmic web” — the enormous hidden structure that connects galaxies across space。 By analyzing more than 164,000 galaxies through the massive COSMOS-Web survey, researchers were able to trace this vast network back to when the universe was just a