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By analogy with the Cayley graph of a group with respect to a finite generating set or the Cayley-Abels graph of a totally disconnected, locally compact group, we introduce countable connected graphs associated to Polish groups that we term Cayley-Abels-Rosendal graphs. A group admitting a Cayley-Abels-Rosendal graph acts on it continuously, coarsely metrically properly and cocompactly by isometries of the path metric. By an expansion of the Milnor-Schwarz lemma, it follows that the group is generated by a coarsely bounded set and the group equipped with (a suitably compatible alteration of) a word metric with respect to a coarsely bounded generating set and the graph are quasi-isometric. In other words, groups admitting Cayley-Abels-Rosendal graphs are topological analogues of the finitely generated groups. Our goal is to introduce this topological perspective to a geometric group theorist. We apply these concepts to homeomorphism groups of countable Stone spaces. We completely characterize when these homeomorphism groups are coarsely bounded, when they are locally bounded (all of them are), and when they admit a Cayley-Abels-Rosendal graph, and if so produce a coarsely bounded generating set., Comment: 19 pages, 6 figures

Driving the nuclear fusion reaction p+11B -> 3 alpha + 8.7 MeV in laboratory conditions, by interaction between high-power laser pulses and matter, has become a popular field of research, due to numerous applications that it can potentially allow: an alternative to deuterium-tritium (DT) for fusion energy production, astrophysics studies and alpha-particle generation for medical treatments. A possible scheme for laser-driven p-11B reactions is to direct a beam of laser-accelerated protons onto a boron sample (the so-called 'pitcher-catcher' scheme). This technique was successfully implemented on large, energetic lasers, yielding hundreds of joules per shot at low repetition. We present here a complementary approach, exploiting the high-repetition rate of the VEGA III petawatt laser at CLPU (Spain), aiming at accumulating results from many interactions at much lower energy, for better controlling the parameters and the statistics of the measurements. Despite a moderate energy per pulse, our experiment allowed exploring the laser-driven fusion process with tens (up to hundreds) of laser shots. The experiment provided a clear signature of the produced reactions and of the fusion products, accumulated over many shots, leading to an improved optimization of the diagnostic for these experimental campaigns In this paper we discuss the effectiveness of the laser-driven p-11B fusion in the pitcher-catcher scheme, at high-repetition rate, addressing the challenges of this experimental scheme and highlighting its critical aspects. Our proposed methodologies allow evaluating the performance of this scheme for laser-driven alpha particle production and can be adapted to high-repetition rate laser facilities with higher energy and intensity.

We show that the group $\langle a,b,c,t : a^t=b,b^t=c,c^t=ca^{-1} \rangle$ is profinitely rigid amongst free-by-cyclic groups, providing the first example of a hyperbolic free-by-cyclic group with this property., Comment: 4 pages. Comments welcome!

We present experimental evidence of multiple blood flow configurations in a relatively simple microfluidic network under constant inlet conditions. We provide evidence of multistability and unsteady dynamics and find good agreement with a theoretical {one-dimensional advection} model for blood flow in microvascular networks{ that relies on the widely used laws for rheology and phase separation}. We discuss the ramifications for microfluidic experiments and measurements using blood and implications for in vivo microcirculation. Our findings suggest that further modeling in microvascular networks should discard the usual assumption of unique, steady-state flow solutions, with crucial consequences regarding gas, nutrient, and waste transport.

Recently, Baykara, Tarazi and Vafa discussed the existence of quasicrystalline string vacua that contain a single neutral moduli, the dilaton, and studied compactifications of the non-supersymmetric $SO(16)\times SO(16)$ heterotic-string on these spaces. We discuss a specific class of quasi-realistic string vacua with similar properties that has been known since the late eighties and analyse the vacuum energy in several non-supersymmetric examples that correspond to compactifications of tachyon free ten dimensional vacua as well as compactifications of tachyonic ten dimensional vacua. Our analysis uses the Free Fermionic Formalism of the heterotic-string in four dimensions and employs asymmetric boundary conditions that project all the geometrical moduli by Generalised GSO projections. This methodology produces models with both positive and negative spacetime potential at one-loop., Comment: 16 pages, 0 figures

We use the free fermionic formulation of the heterotic-string in four dimensions to study the vacuum structure and energy of non-supersymmetric tachyon free models that correspond to compactifications of tachyonic vacua of the ten dimensional heterotic-string. We explore the class of heterotic $SO(10)$ non-supersymmetric models constructed from the $\tilde{S}$-model in the Free Fermionic Formalism, and investigate the dependence of the potential on the geometric moduli. This paper will explore a sample of $ 10^{9}$ string vacua to find the frequency of viable models, classifying these vacua by the following fertility criteria: tachyon presence; number of spinorial $\boldsymbol{16/\overline{16}}$ representations; vectorial $\boldsymbol{10}$ states; Top Quark Mass Coupling compatibility. Of these we find those that mimic supersymmetric models with equal number of bosons and fermions at the massless level - $a_{00} = 0$. Tachyon free models occur with a frequency of $5.309\times10^{-3}$. Furthermore, models that fulfil the rest of the phenomenological fertility conditions and the additional condition on $a_{00}$ occur with probability $4.0 \times 10^{-9}$ We analyse the partition functions and study the moduli dependence of such models, finding that almost all fertile models have finite, positive potential at the Free Fermionic Point, with $2$ out of $84$ of the fertile cores having negative, finite potential. We demonstratate that the Free Fermionic Point is not necessarily a minimum in the potential. This work provides further evidence that supersymmetry may not be a necessary ingredient of phenomenological models, recreating many of the desirable features of such models without employing supersymmetry., Comment: 24 pages, 3 figures

Deep learning offers promising new ways to accurately model aleatoric uncertainty in robotic estimation systems, particularly when the uncertainty distributions do not conform to traditional assumptions of being fixed and Gaussian. In this study, we formulate and evaluate three fundamental deep learning approaches for conditional probability density modeling to quantify non-Gaussian aleatoric uncertainty: parametric, discretized, and generative modeling. We systematically compare the respective strengths and weaknesses of these three methods on simulated non-Gaussian densities as well as on real-world terrain-relative navigation data. Our results show that these deep learning methods can accurately capture complex uncertainty patterns, highlighting their potential for improving the reliability and robustness of estimation systems., Comment: 8 pages, 7 figures

In complex industrial and chemical process control rooms, effective decision-making is crucial for safety and efficiency. The experiments in this paper evaluate the impact and applications of an AI-based decision support system integrated into an improved human-machine interface, using dynamic influence diagrams, a hidden Markov model, and deep reinforcement learning. The enhanced support system aims to reduce operator workload, improve situational awareness, and provide different intervention strategies to the operator adapted to the current state of both the system and human performance. Such a system can be particularly useful in cases of information overload when many alarms and inputs are presented all within the same time window, or for junior operators during training. A comprehensive cross-data analysis was conducted, involving 47 participants and a diverse range of data sources such as smartwatch metrics, eye-tracking data, process logs, and responses from questionnaires. The results indicate interesting insights regarding the effectiveness of the approach in aiding decision-making, decreasing perceived workload, and increasing situational awareness for the scenarios considered. Additionally, the results provide valuable insights to compare differences between styles of information gathering when using the system by individual participants. These findings are particularly relevant when predicting the overall performance of the individual participant and their capacity to successfully handle a plant upset and the alarms connected to it using process and human-machine interaction logs in real-time. These predictions enable the development of more effective intervention strategies.

In measurement, a reference frame is needed to compare the measured object to something already known. This raises the neuroscientific question of which reference frame is used by humans when exploring the environment. Previous studies suggested that, in touch, the body employed as measuring tool also serves as reference frame. Indeed, an artificial modification of the perceived dimensions of the body changes the tactile perception of external object dimensions. However, it is unknown if such a change in tactile perception would occur when the body schema is modified through the illusion of owning an limb altered in size. Therefore, employing a virtual hand illusion paradigm with an elongated forearm of different lengths, we systematically tested the subjective perception of distance between two points (tactile distance perception task, TDP task) on the corresponding real forearm following the illusion. Thus, TDP task is used as a proxy to gauge changes in the body schema. Embodiment of the virtual arm was found significantly greater after the synchronous visuo-tactile stimulation condition compared to the asynchronous one, and the forearm elongation significantly increased the TDP. However, we did not find any link between the visuo-tactile induced ownership over the elongated arm and TDP variation, suggesting that vision plays the main role in the modification of the body schema. Additionally, significant effect of elongation found on TDP but not on proprioception suggests that these are affected differently by body schema modifications. These findings confirm the body schema malleability and its role as reference frame in touch.

Transferring to a four-year institution is an important pathway to student success. Many students who enroll in community college intend to transfer to a four-year institution and subsequently earn a bachelor's degree. However, few students ultimately do, with low-income students transferring at lower rates than their peers. The Texas Transfer Grant Pilot Program was created by the Texas Higher Education Coordinating Board (THECB) to improve the transfer rates of students from two-year to four-year institutions in Texas. The pilot program offered $5,000 grants to community college students who performed well academically, came from low-income backgrounds, and transferred to a public four-year institution. MDRC's evaluation of the program, conducted in partnership with the THECB, used Texas statewide administrative data to identify and randomly assign about 90,000 eligible students. Students were assigned to either a program group (whose members were notified they were eligible to receive the grant for the fall 2022 semester) or a control group (whose members did not receive a Texas Transfer Grant offer but who could seek business-as-usual financial aid resources). Students assigned to the program group were informed of the opportunity to receive a grant via email and hard-copy letters. This brief answers the following two primary questions: (1) Does offering the Texas Transfer Grant to community college students affect their enrollment rates at four-year higher education institutions in Texas? and (2) What do community college students think--and how do they feel--about the Texas Transfer Grant offer, particularly with respect to their decision to transfer to a four-year institution? Although additional research is needed to fully understand the impact of the grant offer, early findings indicate that the pilot program increased the proportion of students who enrolled in Texas public four-year institutions. [For the supplement, "Differential Impacts on Fall 2022 Enrollment at Any Four-Year Institution. A Supplement to Texas Takes on Transfer Grants," see ED627376.]

Using a survey of international students from three different IHEs across the United States and follow-up focus groups, we gathered feedback directly from current international students studying in the United States on the practices and policies they have found most and least helpful in terms of supporting them in their studies and their suggestions for additional ways IHEs might better support their international students. Our findings suggest that international students are generally satisfied with the support provided by their international student offices at their institutes of higher education, although they also identified several areas for improvement. In both the surveys and the focus groups, participants emphasized the need for practical assistance with finding housing in the United States and navigating the complexities of attaining a social security number so they can open bank accounts, buy cell phones, and apply for leases on apartments. They also discussed the need to foster the development of meaningful friendships with other international students as well as students from the United States and for ensuring that the mental/emotional health of students, as well as their academic progress, are looked after. Suggestions for ways IHEs might address these identified needs are discussed.

Laser technologies improved after the understanding of the Chirped Pulse Amplification (CPA) which allows energetic laser beams to be compressed to tens of femtosecond (fs) pulse durations and focused to few $\mu$m. Protons of tens of MeV can be accelerated using for instance the Target Normal Sheath Acceleration (TNSA) method and focused on secondary targets. In such conditions, nuclear reactions can occur and radioisotopes relevant for medical purposes be produced. High repetition lasers can be used to produce enough isotopes for medical applications. This route is competitive to conventional methods mostly based on accelerators. In this paper we study the production of $^{67}$Cu, $^{63}$Zn, $^{18}$F and $^{11}$C currently used in positron emission tomography (PET) and other applications. At the same time, we study the reaction $^{10}$B(p,$\alpha$)$^{7}$Be and $^{70}$Zn(p,4n)$^{67}$Ga to put further constraints to the proton distributions at different angles and to the reaction $^{11}$B(p,$\alpha$)$^{8}$Be relevant for energy production. The experiment was performed at the 1 petawatt (PW) laser facility at Vega III located in Salamanca-Spain. Angular distributions of radioisotopes in the forward (with respect to the laser direction) and backward directions were measured using a High Purity Germanium Detector (HPGE). Our results are reasonably reproduced by the numerical estimates following the approach of Kimura et al. (NIMA637(2011)167)

More than half of community college students nationwide intend to pursue a four-year degree; however, in Texas only one in four community college students transfer to four-year institutions successfully. Among students who do transfer to a Texas four-year institution, roughly 60 percent go on to graduate with a bachelor's degree. The result is that only about 15 percent of Texans who start at a community college end up graduating from a four-year institution. To improve transfer rates and, ultimately, bachelor's degree attainment, the Texas Higher Education Coordinating Board (THECB) launched the Texas Transfer Grant Pilot Program with money provided by the U.S. Department of Education's Governor's Emergency Education Relief (GEER) Fund. MDRC evaluated the pilot program to build evidence about its efficacy and help inform future THECB decisions about the program. This policy brief follows up with additional findings about the pilot program's impact on students' enrollment and academic outcomes at Texas four-year institutions during the fall 2022 and spring 2023 semesters--two semesters after students initially received the fall 2022 transfer grant.

Quotation extraction is a widely useful task both from a sociological and from a Natural Language Processing perspective. However, very little data is available to study this task in languages other than English. In this paper, we present a manually annotated corpus of 1676 newswire texts in French for quotation extraction and source attribution. We first describe the composition of our corpus and the choices that were made in selecting the data. We then detail the annotation guidelines and annotation process, as well as a few statistics about the final corpus and the obtained balance between quote types (direct, indirect and mixed, which are particularly challenging). We end by detailing our inter-annotator agreement between the 8 annotators who worked on manual labelling, which is substantially high for such a difficult linguistic phenomenon.

Large scientific collaborations, often with hundreds or thousands of members, are an excellent opportunity for a case study in best practices implemented while developing open source hardware. Using a publicly available design of timing equipment for gravitational wave detectors as a case study, we evaluated many facets of the open source hardware development, including practices, awareness, documentation, and longevity. Two diverse student teams, composed of high school and college students, participated in an end-to-end exercise of testing publicly-available documented hardware that originated from more than a decade ago. We found that the primary value of large collaborations lie in the ability to cultivate teamwork, provide a diverse set of role-models, and explore the possibilities of open hardware development of varying complexities. Learning from the experiences of the student groups, we make constructive recommendations where the open source hardware community can learn from the collaborations and vice versa.