Physical characterization and origin of binary near-Earth asteroid (175706) 1996 FG3

The near-Earth asteroid (NEA) (175706) 1996 FG3 is a particularly interesting spacecraft target: a binary asteroid with a low-DeltaV heliocentric orbit. The orbit of its satellite has provided valuable information about its mass density while its albedo and colors suggest it is primitive or part of the C-complex taxonomic grouping. We extend the physical characterization of this object with new observations of its emission at mid-Infrared (IR) wavelengths and with near-IR reflection spectroscopy. We derive an area-equivalent system diameter of 1.90 \pm 0.28 km (corresponding to approximate component diameters of 1.83 km and 0.51 km, respectively) and a geometric albedo of 0.039 \pm 0.012. 1996 FG3 was previously classified as a C-type asteroid, though the combined 0.4--2.5 micron spectrum with thermal correction indicates classification as B-type; both are consistent with the low measured albedo. Dynamical studies show that 1996 FG3 has most probably originated in the inner main asteroid belt. Recent work has suggested the inner Main Belt (142) Polana family as the possible origin of another low-DeltaV B-type NEA, (101955) 1999 RQ36. A similar origin for 1996 FG3 would require delivery by the overlapping Jupiter 7:2 and Mars 5:9 mean motion resonances rather than the nu-6 resonance, and we find this to be a low probability, but possible, origin.Comment: Published in Ap

Avoiding Convictions: Regression Discontinuity Evidence on Court Deferrals for First-Time Drug Offenders

This paper studies the causal impact of court deferrals, a legal strategy to help defendants avoid a felony conviction record, on the future criminal and labor market outcomes of first-time felony drug offenders. To accomplish this, we exploit two natural experiments in Harris County, Texas, in which defendants appearing in court one day versus the next experienced abruptly different likelihoods of deferral. In 1994 deferral rates dropped by 34 percentage points the day following the implementation of a penal code reform; in 2007 deferral rates increased by 22 percentage points the day after the unexpected failure of a ballot initiative to expand the county jail. Using administrative data and local polynomial regression discontinuity methods, we find robust evidence consistent across both experiments that regimes with expanded use of court deferrals generated substantially lower rates of reoffending and unemployment over a five-year follow-up period. Additional analysis delves further into the timing, nature and incidence of these impacts. Together our results suggest that increasing the use of deferral programs may be an attractive and feasible option for a jurisdiction seeking to reduce the fiscal cost and community impact of its criminal justice system

Where does In-context Translation Happen in Large Language Models

Self-supervised large language models have demonstrated the ability to perform Machine Translation (MT) via in-context learning, but little is known about where the model performs the task with respect to prompt instructions and demonstration examples. In this work, we attempt to characterize the region where large language models transition from in-context learners to translation models. Through a series of layer-wise context-masking experiments on \textsc{GPTNeo2.7B}, \textsc{Bloom3B}, \textsc{Llama7b} and \textsc{Llama7b-chat}, we demonstrate evidence of a "task recognition" point where the translation task is encoded into the input representations and attention to context is no longer necessary. We further observe correspondence between the low performance when masking out entire layers, and the task recognition layers. Taking advantage of this redundancy results in 45\% computational savings when prompting with 5 examples, and task recognition achieved at layer 14 / 32. Our layer-wise fine-tuning experiments indicate that the most effective layers for MT fine-tuning are the layers critical to task recognition.Comment: 19 pages. Under Revie

Designing strategies for topological interlocking assemblies in architecture. Flat vaults

The modular interlocked blocks in flat structures are known in ancient buildings with pure-compression constructions. Over the last two decades, this structural bond has become relevant, studied by mechanical engineers, and material scientists due to the properties and design freedom that modular structures have. The structural hierarchy existing in topologically interlocked structures enhance the performance, allowing to design and fabricate custom block elements. The main reason to consider this system is that, from the architectural perspective, it is composed by identical modular elements, and it discretizes flat or curved surfaces into elements that work only by contact and compression. This article presents preliminary studies for its application and different approaches for designing discrete interlocked assemblies with a focus on the application for architectural structures: studying the structuralperformance of contact analysis and introducing the combination of topological interlocking with different structural principles

Higher Renal Replacement Therapy Dose Delivery Influences on Drug Therapy

Higher doses of renal replacement therapy have profound effects on pharmacotherapy, yet little research has been conducted in this area. High-volume renal replacement therapies influence both the pharmacokinetic and the pharmacodynamic profiles of all drugs administered to these critically ill patients. Intermittent high-dose “hybrid” hemodialysis therapies remove drugs to a much different degree than standard thrice-weekly hemodialysis, yet pharmacokinetic studies have not been performed in patients receiving these therapies. High-volume continuous renal replacement therapies offer dosing challenges not seen with standard low-dose therapies. This article describes the pharmacokinetic and pharmacodynamic issues presented by high-volume renal replacement therapies. Given the importance that pharmacotherapy has on optimal patient outcomes, a better understanding of the influence that high-volume renal replacement therapy has on drugs is essential if these high volume therapies are to be used successfully in the intensive care unit.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75000/1/j.1525-1594.2003.07283.x.pd

Unlocking Complex Soil Systems as Carbon Sinks: Multi-pool Management as the Key

Much research focuses on increasing carbon storage in mineral-associated organic matter (MAOM), in which carbon may persist for centuries to millennia. However, MAOM-targeted management is insufficient because the formation pathways of persistent soil organic matter are diverse and vary with environmental conditions. Effective management must also consider particulate organic matter (POM). In many soils, there is potential for enlarging POM pools, POM can persist over long time scales, and POM can be a direct precursor of MAOM. We present a framework for context-dependent management strategies that recognizes soils as complex systems in which environmental conditions constrain POM and MAOM formation

Lrig3 is Required in Recovery from Acute Inflammatory Assault

46 pagesBackground and Aim. The mouse colon contains a suite of genes that provide a framework from which the structure and function of the colon is tightly regulated. The colon contains crypts: small, U-shaped invaginations in the epithelial layer that absorb water and secrete mucus. A gene from this suite of regulatory genes is called Leucine-rich repeats and immunoglobulin-like domains 3 (Lrig3), may regulate the size and structure of a specialized region of the colonic crypts. In homeostasis, Lrig3-/- mice have longer colons, taller crypts, more cells per crypt, and more stem and progenitor cells than wildtype (WT) mice. This indicates that Lrig3 is required for restricting the size of the stem cell niche. It is unknown if these abnormalities perturb the regenerative capabilities of the colon. The aim of my study was to test the hypothesis that loss of Lrig3 impairs colonic regeneration after acute inflammatory assault. Method. To address our study aims, we administered WT (B6, n=4) and Lrig3-/- mice (n=4) 3% Dextran Sodium Sulfate (DSS) in drinking water for seven days to cause crypt destruction and local inflammation. We initially sought to examine crypt regeneration over the subsequent seven days, but the Lrig3-/- mice lost >20% of their body weight and the study had to be halted 24 hours after resumption of normal drinking water, due to this extreme and unexpected weight loss. We then sacrificed all mice in both cohorts at this time, extracted the colons and performed anatomical, morphometric, protein expression, and analysis for genes associated with crypt structure and regeneration. Results. Lrig3-/- mice displayed a higher susceptibility to DSS treatment than WT as supported by greater weight loss and increased colon shortening. Compared to WT mice, Lrig3-/- mice expressed lower levels of Ki-67+ cells/epithelial area (p=0.045). Lrig3-/- mice also had decreased Lrig1-positive cells per crypt (p<0.01). Cell death analysis revealed a greater number of TUNEL-positive cells in the base of the crypt of Lrig3-/- mice (p<0.01). Immunofluorescent analysis for markers of both secretory and absorptive epithelial cell lineages was not significantly different between genotypes after acute inflammatory assault. Finally, we found key receptor kinase signaling pathways were not aberrantly regulated at 24 hours after the DSS time course. (All statistical tests were a two-tailed student's t-test assuming unequal variance). Conclusion. My study has determined that loss of Lrig3 significantly impairs colonic regeneration after acute inflammatory assault. While the role of Lrig3 in colon homeostasis is still under investigation, Lrig3 protein plays a key role in colonic regeneration after injury, yet the mechanism of action remains unknown