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We present an optical aberration correction technique for ultracold quantum gas experiments which directly utilizes the quantum gas as a wavefront sensor. The direct use of the quantum gas enables correcting aberrations that are otherwise impractical to measure, e.g. introduced by vacuum windows. We report a root-mean-square precision and accuracy of 0.01{\lambda} and 0.03{\lambda}, respectively, and also show independently the reduction of aberrations through measurement of the trap frequency of our optical tweezer. These improvements were achieved for a tweezer size that is well below our imaging resolution. The present work is in particular intended to serve as a tutorial for experimentalists interested in implementing similar methods in their experiment., Comment: 11 pages, 6 figures

This project is part of the American School District Panel (ASDP), a research partnership between the RAND Corporation and the Center on Reinventing Public Education at Arizona State University's Mary Lou Fulton Teachers College (CRPE). This report concludes research on five school systems to reveal the academic, social, and political challenges posed by the pandemic and what leaders and their staff are doing to address student learning loss. This report provides a possible explanation for why lackluster student test scores continue and why school systems struggle to implement and scale targeted student supports. Significant findings in this report include: (1) A crisis in the quality of classroom teaching is, leaders say, diverting time and resources away from targeted supports for students and toward improving classroom instruction; (2) Leaders report less day-to-day chaos, but unexpected challenges in staffing and teacher development have curtailed recovery efforts. As a result, their COVID recovery plans have been difficult, if not impossible, to carry out; (3) Plans for tutoring and other customized help have been undone by leaders' need to build (or rebuild) teachers' core skills; and (4) Millions of dollars and the best of intentions and efforts notwithstanding, leaders are struggling to overcome challenges to providing baseline services to students. [For the preceding report, see "Navigating Political Tensions over Schooling: Findings from the Fall 2022 American School District Panel Survey" (ED626297).]

We realize a Laughlin state of two rapidly rotating fermionic atoms in an optical tweezer. By utilizing a single atom and spin resolved imaging technique, we sample the Laughlin wavefunction, thereby revealing its distinctive features, including a vortex distribution in the relative motion, correlations in the particles' relative angle, and suppression of the inter-particle interactions. Our work lays the foundation for atom-by-atom assembly of fractional quantum Hall states in rotating atomic gases.

Public schooling has always been politically fraught, but current disagreements over issues related to race, sexuality, gender, and COVID-19 have reached a tipping point. According to this report from the Center on Reinventing Public Education and RAND, half of school system leaders say that these disagreements are disrupting schooling. Almost one in three district leaders also said their educators had received verbal or written threats about politically controversial topics since fall 2021. The findings come from surveys issued to 300 district and charter network leaders and interviews with superintendents. Their responses shed light on how political polarization has affected classrooms and how districts are responding. This report presents results from the fall 2022 survey of the American School District Panel (ASDP). The ASDP is a research partnership between RAND and CRPE. The panel also collaborates with several other education organizations, including the Council of the Great City Schools and Kitamba, to help improve outcomes for students throughout the United States.

In this report, we update our ongoing research on five school systems to reveal the academic, social, and political challenges posed by the pandemic and what system leaders and their staff are doing to address student learning loss. The report is part of the American School District Panel, a research partnership between the RAND Corporation and the Center on Reinventing Public Education. Key findings include: (1) Student absences and staff shortages have sidelined the adoption of academic acceleration strategies; (2) Districts are working hard to rebuild teacher capacity and collect better data on student performance; (3) Some districts are turning back to familiar instructional strategies developed before the pandemic. Others are offering different types of support for student academic recovery to address learning loss; and (4) The pandemic has changed district priorities and reshaped the work of superintendents and senior administrators. Districts haven't given up on restoring lost learning or improving classroom instruction. But to help students who spent months out of school, they're applying high-dosage tutoring, project-based learning and career-infused education in a piecemeal fashion, rather than pursuing academic acceleration as a comprehensive approach. [For the previous report in the series, "Whack-A-Mole: School Systems Respond to Disrupted Learning in 2021," see ED618897.]

Public education depends on expertise, work, money, and cooperation from multiple actors who have different interests and beliefs. These lead to competition and negotiation--in other words, politics. Failure to consider the politics of reform implementation and sustainability has doomed many promising K-12 school improvement initiatives. This paper analyzes more than 10 years of data on the implementation of the portfolio strategy to identify practical lessons on managing the politics of reform K-12 schools. Sustaining complex reforms like the portfolio strategy in a political environment requires leaders to: (1) Continually seek new supporters and renew the support of existing ones; (2) Expect and prepare for attacks and be alert to the unnecessary harms caused by their own actions, which bolster opposition; (3) Develop information strategies that document intermediate results, alert leaders to emergent problems and actively counter hostile narratives; (4) Be attentive to competing agendas and political liabilities within their own alliances; and (5) Prepare for leadership succession so that reforms have a chance to last long enough to make a difference. These observations challenge the conventional wisdom that sustainable reforms can be built only upon the percolating up of good ideas and initiatives from below. Reform leaders are essential to knitting together fragile coalitions who may be motivated by different goals and aligning new programs and initiatives--and politically reinforcing them over time--so their benefits can accumulate.

This is Center on Reinventing Public Education (CRPE)'s second consensus panel report on the pandemic and delays in students' learning. Based on the evidence available a year ago, CRPE reported the average K-12 student in America mastered less academic content due to the pandemic and associated disruptions to schooling. Negative impacts were generally larger in math than in reading, substantial across all grade levels, larger where students had less access to in-person instruction, and larger for Black, Hispanic, and low-income students. This year's report, based on 23 studies published since last July, offers even stronger evidence of the pandemic's negative consequences for student growth and development. The pauses to in-person schooling and related changes in family and community life over the past year continued to interrupt most children's academic growth, but the consequences are not evenly distributed. Children whose schools were closed the longest had their learning interrupted the most--and most often, that affected low-income children and children of color in big cities. In 2022 as in 2021, the authors aim to present a coherent baseline of what is known, unknown, and needs to be known at this stage of the pandemic--and the beginning of a recovery from the pandemic. These reports are designed to help system leaders, community leaders, policymakers, researchers, philanthropies, the media, and others to define ambitious goals and clear metrics that ensure our education system meets every student's needs over the coming years. [This report is an update to "How Much Have Students Missed Academically Because of the Pandemic? A Review of the Evidence to Date" (ED614130).]

In this report, we complement our latest fall 2021 survey research from the American School District Panel with in-depth interviews of leaders on the ground in five school systems. Our goal with these interviews was to learn from system leaders about the academic needs of children as they return to school, how districts and charter schools are addressing those needs, and how the pandemic has affected schools. In Brief: (1) Education leaders across the country recognize that students are falling behind academically during the pandemic. Some districts are responding by emphasizing grade-level instruction and just-in-time supports rather than remediation. We interviewed top leaders in five school systems committed to this approach to learn more about its implementation; (2) We found that implementing acceleration required school systems to work with schools in new ways, but the strategy was complicated by a host of factors that made getting to instruction difficult: challenging student behaviors, staffing shortages, and the politicization of health, safety, and education. All these pressures have made leading school districts in 2021-22 like playing a game of Whack-A-Mole; and (3) School districts across the country are working hard to catch students up. But the Whack-A-Mole experience of leading during the pandemic raises questions about how these pressures will affect system leaders and leadership and whether, in the future, schools alone will be able to do enough to help all students get the help they need to recover. [For latest fall 2021 survey research from the American School District Panel, "Flux in the Educator Labor Market: Acute Staff Shortages and Projected Superintendent Departures. Selected Findings from the Fourth American School District Panel Survey. Data Note: Insights from the American Educator Panels. Research Report. RR-A956-9," see ED617372.]

This report is part of the American School District Panel (ASDP), a joint project between the Center on Reinventing Public Education, the RAND Corporation, Chiefs for Change, the Council of Great City Schools, and Kitamba, an education consulting firm. The ASDP's primary work is conducting a series of nationally-representative surveys of school districts. In this report, we complement our survey research with in-depth interviews of leaders on the ground in six school systems. Our goal was to learn how these system leaders approached and managed student learning during this difficult year and to gauge what it means for the future. We found: (1) When it came to instruction, the school systems favored "acceleration" over remediation; (2) School systems that had coherent instructional systems in place before the pandemic had an easier time delivering grade-level content; and (3) In some cases, improving instruction alone may not be enough. Two of the systems that faced deeper inequity and performance challenges before the pandemic were considering more fundamental shifts. What happens next will depend not only on district actions but on the nature and depth of students' academic and social needs, which will only become clear over time. [This report was produced by the American School District Panel (ASDP).]

A significant number of researchers have applied deep learning methods to image fusion. However, most works require a large amount of training data or depend on pre-trained models or frameworks to capture features from source images. This is inevitably hampered by a shortage of training data or a mismatch between the framework and the actual problem. Deep Image Prior (DIP) has been introduced to exploit convolutional neural networks' ability to synthesize the 'prior' in the input image. However, the original design of DIP is hard to be generalized to multi-image processing problems, particularly for image fusion. Therefore, we propose a new image fusion technique that extends DIP to fusion tasks formulated as inverse problems. Additionally, we apply a multi-channel approach to enhance DIP's effect further. The evaluation is conducted with several commonly used image fusion assessment metrics. The results are compared with state-of-the-art image fusion methods. Our method outperforms these techniques for a range of metrics. In particular, it is shown to provide the best objective results for most metrics when applied to medical images.

While state policymakers are ultimately responsible for public schools statewide, their influence over local school districts has always been incomplete at best. State chiefs, the ostensible leaders of state education agencies, have limited powers and local school boards ultimately control most of the money and staff. As a result, when state leaders seek change in local school systems--whether to address financial mismanagement, corruption, or weak outcomes for students--they are often stymied by factors outside of their control. State takeovers of local school districts emerged as one strategy for overcoming these limitations on state authority. State takeovers suspend the powers of local boards and put in place a state-appointed superintendent. They aim to provide states a direct means for influencing the oversight and operation of local schools that does not hinge on gaining local leaders' cooperation. While state takeovers can be powerful, they are never permanent. To understand how state leaders have sought to sustain the hard-won improvements they gained through state takeovers, the authors interviewed a total of 10 current and former senior state officials who had overseen state takeovers or served as state-appointed superintendents. The interviews provide key lessons for states seeking to make improvements in districts and schools navigating a transition to local control, and emphasize the need to focus on sustainability well before state interventions begin. The authors summarize the main themes that emerged from their interviews in three sections: (1) State takeover is an important but limited tool; (2) States must build a local political base for takeover-initiated reforms; and (3) Exit strategies must set the conditions for long-term success.

The current debate about charter schools' effects on school district finances hinges on enrollment loss. Critics claim that the surge in charter enrollment in California since 2000 has driven enrollment loss statewide--cutting districts' income more than their costs, especially in cities where many students attend charter schools. State officials are under pressure to cap the growth of charter schools as a way of stabilizing district enrollments, and thus finances. This brief examines state and district data on district and charter school enrollment trends over the past 10 years. We pay particular attention to Los Angeles, Oakland, and San Diego, where claims of harm done by charter enrollment growth have been made most often. The brief makes three points: (1) Surges and declines in K-12 enrollment have long been a fact of life in California districts. Statewide numbers of school-age children are currently falling and will continue to do so; (2) The growth of charter schools cannot account for all of the enrollment loss experienced by urban school districts; and (3) Charter school enrollment is not currently a major factor in continued district enrollment decline. [To view "Do Charter Schools Cause Fiscal Distress in School Districts?" see ED595169 and "Do the Costs of California Charter Schools Outweigh the Benefits?" see ED595193.]

Much attention has been focused on the costs charter school enrollment imposes on school districts. Getting an honest answer to this question is important for school districts so that they may adjust their expenditures appropriately. However, as Ladd and Singleton, the authors of a North Carolina study attempting to quantify those costs point out, a broader analysis of the societal benefits and costs associated with charter school policy also is needed to help policymakers assess the value of the policy and whether it should be continued or adjusted. This brief offers a discussion of the types of benefit and cost issues that should be considered and points to evidence to inform those considerations. First we consider potential benefits, then costs, and finally how we might compare the two. It is not meant to be a definitive analysis, but rather a way to bring nuanced discussion and debate to politically laden issues. We argue that, on face, the public policy benefits of charter schooling in California are more evident than the costs. However, more data and benefit-cost analysis are needed to make a clear determination. [To view "Charter Schools and District Enrollment Loss," see ED595191 and "Do Charter Schools Cause Fiscal Distress in School Districts?" see ED595169.]

The claim that charter schools cause financial harm to school districts is a major element in the debate around charter schools in California. Critics allege that enrollment in charter schools drains resources from school districts, forcing them to make cuts to staff and services and eventually contributing to fiscal distress. The charge that enrollment loss causes harm to students instead of inspiring school districts to improve is a critical question and requires good evidence to answer. This brief examines the relationship between charter school enrollment and fiscal distress in California. We find no evidence that charter school enrollments increase the likelihood of school districts entering fiscal distress. Prior research suggests a variety of factors contribute to fiscal distress and as a result, state policymakers are unlikely to find resolution to the problem in the charter sector. [For "Charter Schools and District Enrollment Loss," see ED595191. For "Do the Costs of California Charter Schools Outweigh the Benefits?" see ED595193.]

A big part of the video content we consume from video providers consists of genres featuring low-light aesthetics. Low light sequences have special characteristics, such as spatio-temporal varying acquisition noise and light flickering, that make the encoding process challenging. To deal with the spatio-temporal incoherent noise, higher bitrates are used to achieve high objective quality. Additionally, the quality assessment metrics and methods have not been designed, trained or tested for this type of content. This has inspired us to trigger research in that area and propose a Grand Challenge on encoding low-light video sequences. In this paper, we present an overview of the proposed challenge, and test state-of-the-art methods that will be part of the benchmark methods at the stage of the participants' deliverable assessment. From this exploration, our results show that VVC already achieves a high performance compared to simply denoising the video source prior to encoding. Moreover, the quality of the video streams can be further improved by employing a post-processing image enhancement method.

The production of neutron-rich isotopes and the occurrence of neutron capture cascades via laser-driven (pulsed) neutron sources are investigated theoretically. The considered scenario involves the interaction of a laser-driven neutron beam with a target made of a single type of seed nuclide. We present a comprehensive study over $95$ seed nuclides in the range $3\le Z \le 100$ from $^7_3$Li to $^{255}_{100}$Fm. For each element, the heaviest sufficiently-long-lived (half life $> 1$ h) isotope whose data is available in the recent ENDF-B-VIII.0 neutron sublibrary is considered. We identify interesting seed nuclides with good performance in the production of neutron-rich isotopes where neutron capture cascades may occur. The effects of the neutron number per pulse, the neutron-target interaction size and the number of neutron pulses are also analyzed. Our results show the possibility of observing up to $4$ successive neutron capture events leading to neutron-rich isotopes with $4$ more neutrons than the original seed nuclide. This hints at new experimental possibilities to produce neutron-rich isotopes and simulate neutron capture nucleosynthesis in the laboratory. With several selected interesting seed nuclides in the region of the branching point of the $s$-process ($^{126}_{51}$Sb, $^{176}_{71}$Lu and $^{187}_{75}$Re) or the waiting point of the $r$-process (Lu, Re, Os, Tm, Ir and Au), we expect that laser-driven experiments can shed light on our understanding of nucleosynthesis., Comment: 23 pages, 8 figures, 1 table; discussions added; accepted for publication in Physical Review C

Local superintendents must do an important job while equipped with, at best, modest authority. Superintendents are ultimately responsible for all the schools in their district, and they at least nominally supervise everything that happens in those schools. Yet superintendents cannot count on obedience or even support from the people who work for them, given that both educators and administrators possess wide discretion in implementation. This paper is written to help current and potential superintendents see the full scope of their role and how leaders from various backgrounds can approach it. In a series of studies beginning in the late 1980s, the authors have interviewed superintendents about their successes and failures in building civic support for needed initiatives. The paper draws examples from this earlier work, as well as from Center on Reinventing Public Education's (CRPE's) ongoing tracking of developments in reform-driven cities and the experiences of other public officials whose ability to overcome the structural limitations of their roles offer important lessons for district leadership. Most superintendents, current and aspiring, understand the importance of getting along with other power centers in the school system and the community at large. This paper goes further by attempting to show how superintendents can build coalitions and thereby exercise real power to accomplish things that conventional wisdom would say are beyond them.

High quality integrated diamond photonic devices have previously been demonstrated in applications from non-linear photonics to on-chip quantum optics. However, the small sample sizes of single crystal material available, and the difficulty in tuning its optical properties, are barriers to the scaling of these technologies. Both of these issues can be addressed by integrating micron scale diamond devices onto host photonic integrated circuits using a highly accurate micro-assembly method. In this work a diamond micro-disk resonator is integrated with a standard single mode silicon-on-insulator waveguide, exhibiting an average loaded Q-factor of 3.1x10^4 across a range of spatial modes, with a maximum loaded Q-factor of 1.05x10^5. The micron scale device size and high thermal impedance of the silica interface layer allow for significant thermal loading and continuous resonant wavelength tuning across a 450 pm range using a mW level optical pump. This diamond-on-demand integration technique paves the way for tunable devices coupled across large scale photonic circuits.

State policy plays a critical role in determining whether and how well local education improvement strategies can be implemented. As states rework their education policies under the Every Student Succeeds Act (ESSA), state and local leaders need a way to assess their current policy environment and identify the changes needed to encourage local innovation and problem-solving. To identify the legal and regulatory barriers to local autonomy, the Center on Reinventing Public Education (CRPE) researched 14 states that already have one or more large cities pursuing local innovation strategies. We find that: The accretion of state law over the years has constrained local education leaders' ability to innovate, improve, and transform their schools; States have set up command-and-control frameworks, viewing districts rather than schools as public education's first responders, which is at odds with school-level efforts to address the particular needs of students and communities; and State policy leads to conflicts and disincentives that play out for worse at the local level. This analysis is intended to help policymakers, education leaders, and advocates understand the changes in state law and policy needed to support local strategies that empower educators, promote new schooling options, and let parents choose.

State chiefs have new responsibilities under the Every Student Succeeds Act, but their formal powers are still limited. Despite these constraints, the Center on Reinventing Public Education (CRPE) analysis finds that chiefs can make a difference by wielding their powers strategically, to build coalitions and persuade others. While turnover in the field is high, with 70% of current chiefs on the job less than two years, newcomers are taking their seats at a time of opportunity. Drawing on interviews with current and former state chiefs, authors Hill and Jochim identify chiefs' opportunities for influence in light of the ideas in Richard E. Neustadt's 1960 book, "Presidential Power and the Modern Presidents: The Politics of Leadership." The analysis and concrete examples are intended to help current and aspiring chiefs understand how to use their authorities as the basis of bargaining, build their professional reputation, and approach decision-making. Key takeaways include: (1) Chiefs should fully understand their own advantages and think hard about how to bargain effectively with others in the state capital and in school districts; (2) Developing new coalitions takes time and sustained attention. By pulling together broader coalitions than normally control education policy, chiefs can expand the horizons of possibility; (3) To build a personal reputation for effectiveness, a chief must have and be known to have strong and specific goals to build something new or to change the status quo--and communicate them to those affected or those who may serve as a source of support; and (4) In order to maximize power, chiefs must approach every decision as an opportunity to strengthen their future effectiveness. This paper is part of a series of publications from CRPE's "Linking State and Local School Improvement" initiative, meant to inform state education leaders, policymakers, and advocacy groups about how to best support promising local school improvement efforts.