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Rigidity of warped cones and coarse geometry of expanders
No full textWe study the geometry of warped cones over free, minimal isometric group actions and related constructions of expander graphs. We prove a rigidity theorem for the coarse geometry of such warped cones: Namely, if a group has no abelian factors, then two such warped cones are quasi-isometric if and only if the actions are finite covers of conjugate actions. As a consequence, we produce continuous families of non-quasi-isometric expanders and superexpanders. The proof relies on the use of coarse topology for warped cones, such as a computation of their coarse fundamental groups
A New Deal for Debtors: Providing Procedural Justice in Consumer Bankruptcy
No full textAcross the criminal and civil justice systems, research regarding procedural justice — feeling that one has a voice, is respected, and is before a neutral and even-handed adjudicator — shows that people’s positive perceptions of legal processes are fundamental to the legal system’s effectiveness and to the rule of law. About a million people file bankruptcy every year, making the consumer bankruptcy system the part of the federal court system with which people most often come into contact. Given the importance of bankruptcy to American families and the credit economy, there should exist a rich literature theorizing and investigating how people’s perceptions of consumer bankruptcy’s procedures advance the system’s goals. Instead, bankruptcy’s procedures have received strikingly little scholarly attention. This Article begins to fill this significant gap by combining procedural justice and related research with what is known about the people who file bankruptcy to craft a theory of consumer bankruptcy’s procedural deficiencies. If consumer bankruptcy is procedurally bankrupt, as this Article posits, then the “fresh start” delivered to struggling households is not nearly as fresh as presumed, which will hamper people’s return to their communities and to the credit economy. As such, the Article proposes two sets of changes to the consumer bankruptcy process — one modest and one more drastic. Both of these new deals for debtors promise to enhance people’s perceptions of bankruptcy’s procedural justice and thereby the legitimacy of the system
Fitting IVIM with Variable Projection and Simplicial Optimization
No full textFitting multi-exponential models to Diffusion MRI (dMRI) data has always been challenging due to various underlying complexities. In this work, we introduce a novel and robust fitting framework for the standard two-compartment IVIM microstructural model. This framework provides a significant improvement over the existing methods and helps estimate the associated diffusion and perfusion parameters of IVIM in an automatic manner. As a part of this work we provide capabilities to switch between more advanced global optimization methods such as simplicial homology (SH) and differential evolution (DE). Our experiments show that the results obtained from this simultaneous fitting procedure disentangle the model parameters in a reduced subspace. The proposed framework extends the seminal work originated in the MIX framework, with improved procedures for multi-stage fitting. This framework has been made available as an open-source Python implementation and disseminated to the community through the DIPY project
Judicial Ethics: A New Paradigm for a New Era
No full textAs the preamble to the Model Code of Judicial Conduct indicates, traditional notions of judicial ethics operate within a rule of law paradigm, which posits that the “three I’s” of judicial ethics—independence, impartiality, and integrity—enable judges to uphold the law. In recent decades, however, social science, public opinion, and political commentary suggest that appointed judges abuse their independence by disregarding the law and issuing rulings in accord with their biases and other extralegal impulses, while elected judges disregard the law and issue rulings popular with voters, all of which calls the future of the three I’s and judicial ethics itself into question. The time has come to rethink the role of judicial ethics in light of a new legal culture paradigm that better accommodates changing conceptions of the judicial role
Small-Molecule Covalent Modification of Conserved Cysteine Leads to Allosteric Inhibition of the TEAD_Yap Protein-Protein Interaction
No full textThe Hippo pathway coordinates extracellular signals onto the control of tissue homeostasis and organ size. Hippo signaling primarily regulates the ability of Yap1 to bind and co-activate TEA domain (TEAD) transcription factors. Yap1 tightly binds to TEAD4 via a large flat interface, making the development of small-molecule orthosteric inhibitors highly challenging. Here, we report small-molecule TEAD⋅Yap inhibitors that rapidly and selectively form a covalent bond with a conserved cysteine located within the unique deep hydrophobic palmitate-binding pocket of TEADs. Inhibition of TEAD4 binding to Yap1 by these compounds was irreversible and occurred on a longer time scale. In mammalian cells, the compounds formed a covalent complex with TEAD4, inhibited its binding to Yap1, blocked its transcriptional activity, and suppressed expression of connective tissue growth factor. The compounds inhibited cell viability of patient-derived glioblastoma spheroids, making them suitable as chemical probes to explore Hippo signaling in cancer
On the front line: Health professionals and system preparedness for Zika virus in Peru
No full textObjectives To analyze the initial healthcare response to the Zika virus in Piura, Peru, and assess the perceptions of midwives and nurses regarding their role in prevention of Zika virus and management of congenital Zika syndrome (CZS). Methods This ethnographic study used a rapid qualitative assessment design. Data were collected through a focus group with midwives and in‐depth interviews with midwives (n=11) and nurses (n=5). Results The focus of the early Zika virus response in Piura was on pregnant women and vector control. Midwives received some training on Zika‐related care during the early response. Nurses did not receive any Zika‐specific training. Neither nurses nor midwives were trained in neonatal CZS surveillance. Midwives were clear about the value and feasibility of incorporating Zika virus surveillance in their daily work, however nurses were not. They referred to lack of training and appropriate tools as limitations. Confusion about Zika virus and CZS symptomatology and effects persisted in both groups. Concerns about their own personal risk influenced the ways they engaged with Zika virus prevention in the community. Conclusion Long‐term management of endemic Zika virus in Piura will require the engagement of both nurses and midwives as primary care providers
Contactless, programmable acoustofluidic manipulation of objects on water
No full textContact-free manipulation of small objects (e.g., cells, tissues, and droplets) using acoustic waves eliminates physical contact with structures and undesired surface adsorption. Pioneering acoustic-based, contact-free manipulation techniques (e.g., acoustic levitation) enable programmable manipulation but are limited by evaporation, bulky transducers, and inefficient acoustic coupling in air. Herein, we report an acoustofluidic mechanism for the contactless manipulation of small objects on water. A hollow-square-shaped interdigital transducer (IDT) is fabricated on lithium niobate (LiNbO3), immersed in water and used as a sound source to generate acoustic waves and as a micropump to pump fluid in the ±x and ±y orthogonal directions. As a result, objects which float adjacent to the excited IDT can be pushed unidirectionally (horizontally) in ±x and ±y following the directed acoustic wave propagation. A fluidic processor was developed by patterning IDT units in a 6-by-6 array. We demonstrate contactless, programmable manipulation on water of oil droplets and zebrafish larvae. This acoustofluidic-based manipulation opens avenues for the contactless, programmable processing of materials and small biosamples
Library Publishers as Educators: Crafting Curriculum for Undergraduate Research Journals
No full textINTRODUCTION Library publishing programs continue to play an increasingly important role in educating their constituents. In particular, library publishers that support undergraduate student journals often provide guidance to students on both mechanical and conceptual issues related to publishing. This article presents a case study for developing a one-credit-hour course to support an undergraduate student journal publication, the Indiana University Journal of Undergraduate Research (IUJUR), at Indiana University Bloomington. DESCRIPTION OF COURSE The course is offered every fall as a mechanism for onboarding about thirty new undergraduate editors. The course was developed and taught by a librarian and an undergraduate student in consultation with IU’s Office of the Vice Provost for Undergraduate Education. Course curriculum touches on topics that scholarly communication and information literacy librarians alike can adapt for a variety of educational contexts, including authentic activities for understanding peer review models and applying publishing innovations. ASSESSMENT The article details both the formative and summative assessment strategies the instructor utilized to gauge student understanding of key publishing concepts. The summative assessment utilizes pre- and post-tests and extends previous library literature to evaluate students’ actual understanding of publishing concepts in addition to their perceived understanding and confidence. LIMITATIONS AND NEXT STEPS The course curriculum will continue to grow and change in order to accommodate students’ misconceptions and interests
White matter alterations in early-stage Alzheimer's disease: A tract-specific study
No full textIntroduction Diffusion magnetic resonance imaging may allow for microscopic characterization of white matter degeneration in early stages of Alzheimer's disease. Methods Multishell Diffusion magnetic resonance imaging data were acquired from 100 participants (40 cognitively normal, 38 with subjective cognitive decline, and 22 with mild cognitive impairment [MCI]). White matter microscopic degeneration in 27 major tracts of interest was assessed using diffusion tensor imaging (DTI), neurite orientation dispersion and density imaging, and q‐space imaging. Results Lower DTI fractional anisotropy and higher radial diffusivity were observed in the cingulum, thalamic radiation, and forceps major of participants with MCI. These tracts of interest also had the highest predictive power to discriminate groups. Diffusion metrics were associated with cognitive performance, particularly Rey Auditory Verbal Learning Test immediate recall, with the highest association observed in participants with MCI. Discussion While DTI was the most sensitive, neurite orientation dispersion and density imaging and q‐space imaging complementarily characterized reduced axonal density accompanied with dispersed and less restricted white matter microstructures
On Placement, Location and Orientation of Wrist-Worn Tri-Axial Accelerometers during Free-Living Measurements
No full textWearable accelerometers have recently become a standalone tool for the objective assessment of physical activity (PA). In free-living studies, accelerometers are placed by protocol on a pre-defined body location (e.g., non-dominant wrist). However, the protocol is not always followed, e.g., the sensor can be moved between wrists or reattached in a different orientation. Such protocol violations often result in PA miscalculation. We propose an approach, PLOE (“Placement, Location and Orientation Evaluation method”), to determine the sensor position using statistical features from the raw accelerometer measurements. We compare the estimated position with the study protocol and identify discrepancies. We apply PLOE to the measurements collected from 45 older adults who wore ActiGraph GT3X+ accelerometers on the left and right wrist for seven days. We found that 15.6% of participants who wore accelerometers violated the protocol for one or more days. The sensors were worn on the wrong hand during 6.9% of the days of simultaneous wearing of devices. During the periods of discrepancies, the daily PA was miscalculated by more than 20%. Our findings show that correct placement of the device has a significant effect on the PA estimates. These results demonstrate a need for the evaluation of sensor position