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We study the self-assembly of halogen-based organic molecules on a passivated silicon surface. The room temperature adsorption of 2,4,6-tris(4-iodophenyl)-1,3,5-triazine (TIPT) on the Si(111)-$\surd$3$\times$$\surd$3-Ag surface is described. The adsorption is investigated primarily by room-temperature scanning tunneling microscopy (STM) and density-functional theoretical (DFT) calculations. The experimental results is a dramatic example of how the substrate can influence the overall structure of the self-assembly. With increasing dose, the TIPT monomers form supramolecular structures defined by a two monomer, 2.07 $\pm$ 0.05 nm by 1.83 $\pm$ 0.05 nm rectangular cell. The unit cell is characterized by zig-zag rows of molecules aligned \pm13{\deg} from the high symmetry directions of the $\surd$3-Ag substrate. The 2.07 nm dimension along the zig-zag rows is very similar to self-assembled TIPT networks observed on HOPG, however the 1.83 nm dimension is extended considerably and commensurate with the $\surd$3-Ag substrate. The epitaxial relationship between the overlayer and the substrate, and the commensurate inter-row spacing indicate significant molecule-substrate interactions. In fact, DFT calculations of free standing TIPT hexamers reveal that increasing the inter row spacing comes at little energy cost. Experiments also indicate that the formation of supramolecular TIPT domains is extremely sensitive to the quality of the underlying $\surd3$-Ag reconstruction. Point defects in the $\surd3$-Ag reconstruction ultimately restricts the extent of the observed domains.

With support from the William Penn Foundation, RFA sought to further examine and understand Black teacher attrition and retention in Philadelphia, and promising strategies and initiatives that can promote the retention of Black teachers in the city and elsewhere. In totality, the project includes qualitative research that centers the perspectives of a small sample of current and former teachers in the Philadelphia area who identify as Black--which is the focus of this report--and a national scan of select teacher diversification initiatives and the particular strategies they employ. The present report shares the storied experiences and actionable recommendations of a sample of 30 current and former Black teachers, organized by salient themes, providing clear and direct insight into factors that contribute to Black teacher attrition as well as ways to retain current teachers. This report describes the study's methodology, presents findings regarding the unique challenges faced by Black teachers, discusses what sustains and retains Black teachers in the profession, and shares their recommendations for increasing Black teacher retention. It concludes with reflections on the implications of these findings and opportunities for future research to further inform policies and practices that best support Black teachers.

The purpose of this brief is to provide school-level examples of how early college practitioners are collecting and using data to improve their practices. Examples three and four are school-level data from two early college partnerships: the MetroWest CPC (Framingham, Milford, Waltham), and Lawrence. The brief begins, however, with the national context that tells researchers what to measure--that is, what outcomes are predictive of college and career success.

We compute the standard Euclidean window of the hadronic vacuum polarization using multiple independent blinded analyses. We improve the continuum and infinite-volume extrapolations of the dominant quark-connected light-quark isospin-symmetric contribution and address additional sub-leading systematic effects from sea-charm quarks and residual chiral-symmetry breaking from first principles. We find $a_\mu^{\rm W} = 235.56(65)(50) \times 10^{-10}$, which is in $3.8\sigma$ tension with the recently published dispersive result of Colangelo et al., $a_\mu^{\rm W} = 229.4(1.4) \times 10^{-10}$, and in agreement with other recent lattice determinations. We also provide a result for the standard short-distance window. The results reported here are unchanged compared to our presentation at the Edinburgh workshop of the g-2 Theory Initiative in 2022., Comment: 24 pages, 15 figures

This report demonstrates the success of the early college high school program at Lawrence High School. It has improved outcomes for participants, significantly increasing the chances that they will enter college right after high school and earn a degree. While no single educational intervention is a panacea, early college deserves to be scaled--in Lawrence and across Massachusetts. The success of Lawrence's early college program is ultimately possible because a well-staffed and collaborative team of educators are leveraging their expertise and commitment to students to make the ambitious dream a reality. The early college team does the daily work of running the program with an eye toward immediate identification of potential stumbling blocks for students and the capacity to respond rapidly with effective solutions. In addition, its work has always been unfailingly championed by district, school, and college leaders engaged in the partnership. The bottom line is that students trust the adults around them to provide guidance and feedback and to have their backs at every step of their way toward a college degree.

The generation of ensembles of gauge configurations is a considerable expense. The preservation and curation of these ensembles constitutes a valuable shared resource for the lattice field theory community. The organizers of Lattice 2022 dedicated a parallel session to the presentation of gauge ensembles and their generation, plans for ensemble publication and data management/storage activities of different collaborations. A summary of the twelve contributions is presented here., Comment: Contribution to the 39th International Symposium on Lattice Field Theory (LATTICE2022), 8-13 August, 2022, Bonn, Germany, 23 pages

"Three Big Lessons in Six Years" is both a reflection on the past and a look ahead to the future at Charlestown (C-Town) High School (Boston, Massachusetts) and other early college programs across the country. The purpose of this series is to document essential design elements, operational structures, and critical support for students to be successful. It also presents an authentic view of the troubleshooting required to overcome key initial challenges. The lessons--"Set a Vision to Guide the Future," "Build a Framework That Allows for Structure and Flexibility" (ED614782), and "Build a 'Both/And' Team" (ED614784)--represent three integral parts of C-Town Pathways' journey. Starting a new early college initiative is complicated. Drawing from the experience of high school and college leaders involved in the launch of the C-Town Pathways early college program--a partnership between Charlestown High School (CHS) and the nearby Bunker Hill Community College (BHCC), supported by JFF--this report, the first of the three lesson reports, outlines strategies to bring partners together around a shared vision and non-negotiables. Starting with a strong unified vision allows for iteration and builds a foundation for future growth and sustainability.

"Three Big Lessons in Six Years" is both a reflection on the past and a look ahead to the future at Charlestown (C-Town) High School (Boston, Massachusetts) and other early college programs across the country. The purpose of this series is to document essential design elements, operational structures, and critical support for students to be successful. It also presents an authentic view of the troubleshooting required to overcome key initial challenges. The lessons--"Set a Vision to Guide the Future" (ED614773), "Build a Framework That Allows for Structure and Flexibility" (ED614782), and "Build a 'Both/And' Team"--represent three integral parts of C-Town Pathways' journey. Launching a successful early college program requires a dedicated team that can both create a vision for the program and keep that program running through day-to-day challenges, ensuring its success. This report, the third of the three lesson reports, shares lessons from the C-Town Pathways early college program--a partnership between Charlestown High School (CHS) and the nearby Bunker Hill Community College (BHCC), supported by JFF--about how to build a "both/and" team that can ensure the success of the partnership between institutions and, even more important, ensure student success.

"Three Big Lessons in Six Years" is both a reflection on the past and a look ahead to the future at Charlestown (C-Town) High School (Boston, Massachusetts) and other early college programs across the country. The purpose of this series is to document essential design elements, operational structures, and critical support for students to be successful. It also presents an authentic view of the troubleshooting required to overcome key initial challenges. The lessons--"Set a Vision to Guide the Future" (ED614773), "Build a Framework That Allows for Structure and Flexibility," and "Build a 'Both/And' Team" (ED614784)--represent three integral parts of C-Town Pathways' journey. As new early college programs welcome the first cohorts of students, an important asset is a pathways framework that lays out a sequence of courses, aligns to degree programs offered at the partnering college, and provides windows into future careers. This report, the second of the three lesson reports, details how staff from the C-Town Pathways early college program--a partnership between Charlestown High School (CHS), an open enrollment high school in Boston Public Schools in Massachusetts, and the nearby Bunker Hill Community College (BHCC), with support from JFF--created a more structured experience that also allows for flexibility and individualization of students' early college journeys.

Massachusetts's education agencies support expanding early college high school programs based on their initial success. In fact, think tank MassINC is calling for annual early college enrollment to increase to 45,000 students. This report outlines strategies for reaching that ambitious target: expanding access to early college programs to students in grades 9 and 10, retaining those who do enroll, and ensuring that these younger students are ready to choose an early college career pathway. It provides guidance and examples to support early college partnerships in expanding their reach to older middle school students and younger high school students.

This paper argues for a radical restructuring of education for grades 11-14--by erasing the arbitrary dividing line between high school and college--to open opportunities for the learners the current systems leave behind. The authors make the case for an entirely new type of institution--neither high school nor college--designed specifically to better meet the needs of young people after 10th grade and help prepare them to succeed in the world of work. The authors take a hard look at the obstacles that impede more than half of the nation's young people from making successful transitions from high school to postsecondary education to the labor market despite the best of intentions of the many who support them. They identify the four key areas that need transformation: (1) incentives (in accountability and finance); (2) alignment; (3) governance; and (4) staffing. For each, the authors provide examples of innovation--existing policies, programs, and networks--that have made strides toward smoothing transitions. Last, the authors recommend an action agenda of next steps to start pushing closer to the ideal. [For the executive summary, see ED614770.]

Early college high schools are powerful instruments for success for young men of color, and school leaders must take an intentional approach to remove systemic barriers to their engagement. This report outlines strategies to better recruit and retain young men of color in early college programs and provides examples of successful and emerging practices that support all youth in preparing for their future careers through early college programs.

We show that using the multi-splitting algorithm as a preconditioner for the domain wall Dirac linear operator, arising in lattice QCD, effectively reduces the inter-node communication cost, at the expense of performing more on-node floating point and memory operations. Correctly including the boundary \textit{snake} terms, the preconditioner is implemented in the QUDA framework, where it is found that utilizing kernel fusion and the tensor cores on NVIDIA GPUs is necessary to achieve a sufficiently performant preconditioner. A reduced-dimension (reduced-$L_s$) strategy is also proposed and tested for the preconditioner. We find the method achieves lower time to solution than regular CG at high node count despite the additional local computational requirements from the preconditioner. This method could be useful for supercomputers with more on-node flops and memory bandwidth than inter-node communication bandwidth., Comment: Add DOI

Phase shifts for $s$-wave $\pi\pi$ scattering in both the $I=0$ and $I=2$ channels are determined from a lattice QCD calculation performed on 741 gauge configurations obeying G-parity boundary conditions with a physical pion mass and lattice size of $32^3\times 64$. These results support our recent study of direct CP violation in $K\to\pi\pi$ decay \cite{Abbott:2020hxn}, improving our earlier 2015 calculation \cite{Bai:2015nea}. The phase shifts are determined for both stationary and moving $\pi\pi$ systems, at three ($I=0$) and four ($I=2$) different total momenta. We implement several $\pi\pi$ interpolating operators including a scalar bilinear "$\sigma$" operator and paired single-pion bilinear operators with the constituent pions carrying various relative momenta. Several techniques, including correlated fitting and a bootstrap determination of p-values have been used to refine the results and a comparison with the generalized eigenvalue problem (GEVP) method is given. A detailed systematic error analysis is performed which allows phase shift results to be presented at a fixed energy., Comment: v3: Add a subsection "Higher partial wave correction", and correct the unit of scattering length. 88 pages and 14 figures v2: 1). Add reference 29 as an example of pipi scattering calculation above 4mpi threshold. 2). Modify the wording on page 3 for the footage. 3). Correct the \sigma operator on page 17

We present a lattice QCD calculation of the $\Delta I=1/2$, $K\to\pi\pi$ decay amplitude $A_0$ and $\varepsilon'$, the measure of direct CP-violation in $K\to\pi\pi$ decay, improving our 2015 calculation of these quantities. Both calculations were performed with physical kinematics on a $32^3\times 64$ lattice with an inverse lattice spacing of $a^{-1}=1.3784(68)$ GeV. However, the current calculation includes nearly four times the statistics and numerous technical improvements allowing us to more reliably isolate the $\pi\pi$ ground-state and more accurately relate the lattice operators to those defined in the Standard Model. We find ${\rm Re}(A_0)=2.99(0.32)(0.59)\times 10^{-7}$ GeV and ${\rm Im}(A_0)=-6.98(0.62)(1.44)\times 10^{-11}$ GeV, where the errors are statistical and systematic, respectively. The former agrees well with the experimental result ${\rm Re}(A_0)=3.3201(18)\times 10^{-7}$ GeV. These results for $A_0$ can be combined with our earlier lattice calculation of $A_2$ to obtain ${\rm Re}(\varepsilon'/\varepsilon)=21.7(2.6)(6.2)(5.0) \times 10^{-4}$, where the third error represents omitted isospin breaking effects, and Re$(A_0)$/Re$(A_2) = 19.9(2.3)(4.4)$. The first agrees well with the experimental result of ${\rm Re}(\varepsilon'/\varepsilon)=16.6(2.3)\times 10^{-4}$. A comparison of the second with the observed ratio Re$(A_0)/$Re$(A_2) = 22.45(6)$, demonstrates the Standard Model origin of this "$\Delta I = 1/2$ rule" enhancement., Comment: Updated to published version. 95 pages, 12 figures

The RBC and UKQCD Collaborations continue to produce 2+1 flavor domain wall fermion ensembles, currently focusing on an ensemble with a $96^3 \times 192$ volume on SUMMIT at ORNL with $1/a \approx 2.8$ GeV, and smaller ensembles at stronger couplings. The $1/a \approx 2.8$ GeV ensemble uses the Exact One Flavor Algorithm for the strange quark, along with the Multisplitting Preconditioned Conjugate Gradient for solving the Dirac equation. We report on our progress and experience to date with the evolution of this ensemble., Comment: 7 pages

We review lattice results related to pion, kaon, $D$-meson, $B$-meson, and nucleon physics with the aim of making them easily accessible to the nuclear and particle physics communities. More specifically, we report on the determination of the light-quark masses, the form factor $f_+(0)$ arising in the semileptonic $K \to \pi$ transition at zero momentum transfer, as well as the decay constant ratio $f_K/f_\pi$ and its consequences for the CKM matrix elements $V_{us}$ and $V_{ud}$. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of $SU(2)_L\times SU(2)_R$ and $SU(3)_L\times SU(3)_R$ Chiral Perturbation Theory. We review the determination of the $B_K$ parameter of neutral kaon mixing as well as the additional four $B$ parameters that arise in theories of physics beyond the Standard Model. For the heavy-quark sector, we provide results for $m_c$ and $m_b$ as well as those for $D$- and $B$-meson decay constants, form factors, and mixing parameters. These are the heavy-quark quantities most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. We review the status of lattice determinations of the strong coupling constant $\alpha_s$. Finally, in this review we have added a new section reviewing results for nucleon matrix elements of the axial, scalar and tensor bilinears, both isovector and flavor diagonal., Comment: 458 pages, 46 figures, 209 tables, 1146 references. Minor changes, version as published in EPJC. arXiv admin note: substantial text overlap with arXiv:1607.00299, arXiv:1310.8555

We show that using the multisplitting algorithm as a preconditioner for conjugate gradient inversion of the domain wall Dirac operator could effectively reduce the inter- node communication cost, at the expense of performing more on-node floating point operations. This method could be useful for supercomputers with far more on-node flops than inter-node communication bandwidth.