cssi/SciSciGPT-SciSciNet huggingface dataset:
Efficient average-case population recovery in the presence of insertions and deletions

Several recent works have considered the \emph{trace reconstruction problem}, in which an unknown source string $x\in\{0,1\}^n$ is transmitted through a probabilistic channel which may randomly delete coordinates or insert random bits, resulting in a \emph{trace} of $x$. The goal is to reconstruct the original string~$x$ from independent traces of $x$. While the best algorithms known for worst-case strings use $\exp(O(n^{1/3}))$ traces \cite{DOS17,NazarovPeres17}, highly efficient algorithms are known \cite{PZ17,HPP18} for the \emph{average-case} version, in which $x$ is uniformly random. We consider a generalization of this average-case trace reconstruction problem, which we call \emph{average-case population recovery in the presence of insertions and deletions}. In this problem, there is an unknown distribution $\cal{D}$ over $s$ unknown source strings $x^1,\dots,x^s \in \{0,1\}^n$, and each sample is independently generated by drawing some $x^i$ from $\cal{D}$ and returning an independent trace of $x^i$. Building on \cite{PZ17} and \cite{HPP18}, we give an efficient algorithm for this problem. For any support size $s \leq \smash{\exp(\Theta(n^{1/3}))}$, for a $1-o(1)$ fraction of all $s$-element support sets $\{x^1,\dots,x^s\} \subset \{0,1\}^n$, for every distribution $\cal{D}$ supported on $\{x^1,\dots,x^s\}$, our algorithm efficiently recovers ${\cal D}$ up to total variation distance $\epsilon$ with high probability, given access to independent traces of independent draws from $\cal{D}$. The algorithm runs in time poly$(n,s,1/\epsilon)$ and its sample complexity is poly$(s,1/\epsilon,\exp(\log^{1/3}n)).$ This polynomial dependence on the support size $s$ is in sharp contrast with the \emph{worst-case} version (when $x^1,\dots,x^s$ may be any strings in $\{0,1\}^n$), in which the sample complexity of the most efficient known algorithm \cite{BCFSS19} is doubly exponential in $s$.
P1-220: A STRUCTURE-BASED MODEL FOR THE ELECTROSTATIC INTERACTION OF THE N-TERMINUS OF PROTEIN TAU WITH THE FIBRIL CORE OF ALZHEIMER'S DISEASE FILAMENTS

Abstract Although portions of tau protein within the microtubule binding region have been shown to form the ordered core of tau filaments, the structural details of how other regions of tau participate in filament formation are so far unknown. In an attempt to understand how the N-terminus of tau may interact with fibril core, we crystallized and determined the structure of the N-terminal segment 5RQEFEV10 of tau. Several lines of evidence have shown the importance of this segment for fibril formation. The crystal structure reveals an out-of-register Class 5 steric zipper with a wet and a dry interface. To examine the possible interaction of 5RQEFEV10 with the tau fibril core, we modeled the binding of the wet interface of the 5RQEFEV10 structure with the 313VDLSKVTSKC322 region of the Alzheimer’s Disease tau filament structures. This model is consistent with, and helps to explain previous findings on the possible interaction of these two segments, distant in sequence. In addition, we discuss the possible conservation of this interaction across multiple polymorphs of tau.
The potential for gas-free measurements of absolute oxygen metabolism during both baseline and activation states in the human brain

Abstract Quantitative functional magnetic resonance imaging methods make it possible to measure cerebral oxygen metabolism (CMRO2) in the human brain. Current methods require the subject to breathe special gas mixtures (hypercapnia and hyperoxia). We tested a noninvasive suite of methods to measure absolute CMRO2 in both baseline and dynamic activation states without the use of special gases: arterial spin labeling (ASL) to measure baseline and activation cerebral blood flow (CBF), with concurrent measurement of the blood oxygenation level dependent (BOLD) signal as a dynamic change in tissue R2*; VSEAN to estimate baseline O2 extraction fraction (OEF) from a measurement of venous blood R2, which in combination with the baseline CBF measurement yields an estimate of baseline CMRO2; and FLAIR-GESSE to measure tissue R2′ to estimate the scaling parameter needed for calculating the change in CMRO2 in response to a stimulus with the calibrated BOLD method. Here we describe results for a study sample of 17 subjects (8 female, mean age = 25.3 years, range 21–31 years). The primary findings were that OEF values measured with the VSEAN method were in good agreement with previous PET findings, while estimates of the dynamic change in CMRO2 in response to a visual stimulus were in good agreement between the traditional hypercapnia calibration and calibration based on R2′. These results support the potential of gas-free methods for quantitative physiological measurements.
A chromosome folding intermediate at the condensin-to-cohesin transition during telophase

Chromosome folding is modulated as cells progress through the cell cycle. During mitosis, condensins fold chromosomes into helical loop arrays. In interphase, the cohesin complex generates loops and topologically associating domains (TADs), while a separate process of compartmentalization drives segregation of active and inactive chromatin. We used synchronized cell cultures to determine how the mitotic chromosome conformation transforms into the interphase state. Using high-throughput chromosome conformation capture (Hi-C) analysis, chromatin binding assays and immunofluorescence, we show that, by telophase, condensin-mediated loops are lost and a transient folding intermediate is formed that is devoid of most loops. By cytokinesis, cohesin-mediated CTCF-CTCF loops and the positions of TADs emerge. Compartment boundaries are also established early, but long-range compartmentalization is a slow process and proceeds for hours after cells enter G1. Our results reveal the kinetics and order of events by which the interphase chromosome state is formed and identify telophase as a critical transition between condensin- and cohesin-driven chromosome folding.
Primary pulmonary hypertension.

Primary pulmonary hypertension (PPH) is a rare disease of unknown aetiology which typically results in right heart failure and death within several years of the onset of symptoms. While there is no cure for PPH, several pharmacological and surgical approaches to treatment have been developed over the past decade which have proved useful in a significant proportion of patients. In particular, vasodilator therapy may produce sustained haemodynamic and symptomatic improvement in up to approximately two-thirds of patients; in the remaining patients, vasodilators may either produce no benefit or result in deterioration. The calcium channel blocking agents are the most widely used oral vasodilators; continuous intravenous infusions of epoprostenol (prostacyclin; prostaglandin I2) have been used in some patients who are refractory to oral therapy, particularly as a bridge to transplantation. While combined heart-lung transplantation has been considered the surgical procedure of choice for severe pulmonary hypertension, single lung transplantation has been performed successfully in a small number of patients, and may be the preferred approach in patients with reasonably preserved right heart function.
Brachytherapy with surgical resection as salvage treatment for recurrent high-grade meningiomas: a matched cohort study.

To evaluate surgical resection with brachytherapy placement as a salvage treatment in patients with recurrent high-grade meningioma who exhausted prior external beam treatment options. Single-center retrospective review of our institutional experience of brachytherapy implantation from 2012 to 2018. The primary outcome of the study was progression free survival (PFS). Secondary outcomes included overall survival (OS) and complications. A matched cohort of patients not treated with brachytherapy over the same time period was evaluated as a control group. All patients had received prior radiation treatment and underwent planned gross total resection (GTR) surgery. A total of 27 cases were evaluated. Compared with prior treatment, brachytherapy implantation demonstrated a statistically significant improvement in tumor control [HR 0.316 (0.101 − 0.991), p = 0.034]. PFS-6 and PFS-12 were 92.3% and 84.6%, respectively. Compared with the matched control cohort, brachytherapy treatment demonstrated improved PFS [HR 0.310 (0.103 − 0.933), p = 0.030]. Overall survival was not statistically significantly different between groups [HR 0.381 (0.073 − 1.982), p = 0.227]. Overall postoperative complications were comparable between groups, although there was a higher incidence of radiation necrosis in the brachytherapy cohort. Brachytherapy with planned GTR improved PFS in recurrent high-grade meningioma patients who exhausted prior external beam radiation treatment options. Future improvement of brachytherapy dose delivery methods and techniques may continue to prolong control rates and improve outcomes for this challenging group of patients.
Commutation error in reduced order modeling of fluid flows

For reduced order models (ROMs) of fluid flows, we investigate theoretically and computationally whether differentiation and ROM spatial filtering commute, i.e., whether the commutation error (CE) is nonzero. We study the CE for the Laplacian and two ROM filters: the ROM projection and the ROM differential filter. Furthermore, when the CE is nonzero, we investigate whether it has any significant effect on ROMs that are constructed by using spatial filtering. As numerical tests, we use the Burgers equation with viscosities ν = 10− 1 and ν = 10− 3 and a 2D flow past a circular cylinder at Reynolds numbers Re = 100 and Re = 500. Our investigation (i) measures the size of the CE in these test problems and (ii) shows that the CE has a significant effect on ROM development for high viscosities, but not so much for low viscosities.
Keep the books on the shelves: Library space as intrinsic facilitator of the reading experience

Abstract Library literature frequently reports projects to remove print collections and replace them with other amenities for patrons. This project challenges the untested assumption that the physical library itself serves no useful function to its users unless they are actively consulting books from the shelves. The alternative hypothesis is that readers benefit from the mere act of studying while in a book-filled environment. To test this possibility, ten subjects completed SAT-style reading comprehension tests in both a traditional library environment, and a renovated chapel that strongly resembles library space except for lacking books. Results provide a reasonable basis to support an expectation that readers perform better on reading comprehension tasks performed in book-rich environments.
Optimized but not maximized cue integration for 3D visual perception

Abstract Reconstructing three-dimensional (3D) scenes from two-dimensional (2D) retinal images is an ill-posed problem. Despite this, 3D perception of the world based on 2D retinal images is seemingly accurate and precise. The integration of distinct visual cues is essential for robust 3D perception in humans, but it is unclear if this is true for non-human primates. Here we assessed 3D perception in macaque monkeys using a planar surface orientation discrimination task. Perception was accurate across a wide range of spatial poses (orientations and distances), but precision was highly dependent on the plane’s pose. The monkeys achieved robust 3D perception by dynamically reweighting the integration of stereoscopic and perspective cues according to their pose-dependent reliabilities. Errors in performance could be explained by a prior resembling the 3D orientation statistics of natural scenes. We used neural network simulations based on 3D orientation selective neurons recorded from the same monkeys to assess how neural computation might constrain perception. The perceptual data were consistent with a model in which two independent neuronal populations representing stereoscopic cues and perspective cues (with perspective signals from the two eyes combined using nonlinear canonical computations) were optimally integrated through linear summation. Perception of combined-cue stimuli was optimal given this architecture. However, an alternative architecture in which stereoscopic cues, left eye perspective cues, and right eye perspective cues were represented by three independent populations yielded two times greater precision than the monkeys. This result suggests that, due to canonical computations, cue integration for 3D perception is optimized but not maximized. Significance Statement Our eyes sense 2D projections of the world, like a movie on a screen, but we perceive the world in 3D. Here we show that non-human primates, like humans, achieve more precise 3D vision by perceptually integrating distinct 3D cues. We also present evidence that perception is influenced by 3D natural scene statistics, and that priors over 3D orientation are subjectively encoded. Using simulations, we examine how neural computation can constrain 3D perception and estimate that perception is half as precise as theoretically possible. Our findings suggest that the concurrence of multiple canonical computations simultaneously optimizes and curbs 3D visual perception, and highlight that what constitutes optimal task performance depends on the underlying neural architecture.
Maximal tracial algebras

We introduce and study the notion of maximal tracial algebras. We prove several results in a general setting based on dual pairs and multiplier pairs. In a special case that X is a Banach space we determine the abelian subalgebras of $${\mathcal {B}}\left( X\right) $$ that are maximal tracial for rank-one tensors. In another special case that $$\mathcal {H\ }$$is a Hilbert space we show that a unital weak-operator closed subalgebra $$ {\mathcal {A}}$$ of $${\mathcal {B}}\left( {\mathcal {H}}\right) $$ is abelian and transitive if and only if it is maximal $$e\otimes e$$-tracial for every unit vector e in $${\mathcal {H}}$$. We also make slight connections between our ideas and the Kadison Similarity Problem and also the Connes’ Embedding Problem.
Solubility of Nitrogen in Methane, Ethane, and Mixtures of Methane and Ethane at Titan-Like Conditions: A Molecular Dynamics Study

We have studied the temperature dependence of the solubility of nitrogen in methane, ethane, and mixtures of methane and ethane using vapor–liquid equilibrium simulations of binary and ternary mixt...
A Novel Printed Fabric Based Porous Capacitive Pressure Sensor For Flexible Electronic Applications

A novel porous polydimethylsiloxane (PDMS) capacitive pressure sensor was fabricated on a fabric platform using additive screen printing process. The porous PDMS was prepared using a mixture of PDMS, sodium hydrogen bicarbonate (NaHCO3) and nitric acid (HNO3) and implemented as a dielectric layer. The fabric based top and bottom electrodes were developed by screen printing silver (Ag) ink on thermoplastic polyurethane (TPU) and permanently attaching it on to a fabric using heat lamination process. The capacitive response of the pressure sensor was recorded for varying pressures ranging from 0 to 900 kPa. A relative capacitance change of ~10%, ~180% and ~300% was obtained for the applied pressure ranges of 0 to 20 kPa, 50 to 200 kPa and 300 to 900 kPa, respectively. The detailed fabrication process of the pressure sensor as well as its capacitive response is analyzed and reported in this paper.
Financial Incentives to Increase Stool Collection Rates for Microbiome Studies in Adult Bone Marrow Transplant Patients

Introduction In order to learn more about the role of the microbiome in hematopoietic stem cell transplantation (HCT), researchers collect stool samples from patients at various time points throughout HCT. However, unlike blood samples or skin swabs, stool collection requires active subject participation, particularly in the outpatient setting, and may be limited by patient aversion to handling stool. Objectives By providing study participants with compensation for their stool samples, we hypothesize that we can significantly increase stool collection rates. Methods We performed a prospective cohort study on the impact of financial incentives on stool collection rates for microbiome studies. The intervention group consisted of allo-HCT patients from 05/2017-05/2018 who were compensated with a $10 gas gift card for each stool sample. The intervention group was compared to a historical control group consisting of allo-HCT patients from 11/2016-05/2017 who provided stool samples before the incentive was implemented. To control for potential changes in collections over time, we also compared a contemporaneous control group of auto-HCT patients from 05/2017-05/2018 with a historical control group of auto-HCT patients from 11/2016-05/2017; neither auto-HCT groups were compensated. Allo-HCT patients were required to give samples at pre-HCT, day 0 (the day of HCT), and days 7, 14, 21, 30, 60, and 90 post-HCT. Auto-HCT patients were required to give samples at pre-HCT and days 7, 14, and 90 post-HCT. Collection rates were defined as the number of samples provided divided by the number of time points for which we attempted to obtain samples. Results There were 35 allo-HCT patients in the intervention group, 19 allo-HCT patients in the historical control group, 142 auto-HCT patients in the contemporaneous control group, and 75 auto-HCT patients in the historical control group. Allo-HCT patients in the intervention group had significantly higher average overall collection rates when compared to the historical control group allo-HCT patients (80% vs 37%, p Conclusion Our results demonstrate that even a modest incentive can significantly increase collection rates. While this study uses a specialized HCT patient population, these results may be generalizable to informing the design of future studies and aid other researchers in obtaining stool samples needed for future microbiome studies.
A curated benchmark of enhancer-gene interactions for evaluating enhancer-target gene prediction methods

Many genome-wide collections of candidate cis-regulatory elements (cCREs) have been defined using genomic and epigenomic data, but it remains a major challenge to connect these elements to their target genes. To facilitate the development of computational methods for predicting target genes, we develop a Benchmark of candidate Enhancer-Gene Interactions (BENGI) by integrating the recently developed Registry of cCREs with experimentally derived genomic interactions. We use BENGI to test several published computational methods for linking enhancers with genes, including signal correlation and the TargetFinder and PEP supervised learning methods. We find that while TargetFinder is the best-performing method, it is only modestly better than a baseline distance method for most benchmark datasets when trained and tested with the same cell type and that TargetFinder often does not outperform the distance method when applied across cell types. Our results suggest that current computational methods need to be improved and that BENGI presents a useful framework for method development and testing.
Coherent control and high-fidelity readout of chromium ions in commercial silicon carbide

Transition metal ions provide a rich set of optically active defect spins in wide bandgap semiconductors. Chromium (Cr4+) in silicon-carbide (SiC) produces a spin-1 ground state with a narrow, spectrally isolated, spin-selective, near-telecom optical interface. However, previous studies were hindered by material quality resulting in limited coherent control. In this work, we implant Cr into commercial 4H-SiC and show optimal defect activation after annealing above 1600 °C. We measure an ensemble optical hole linewidth of 31 MHz, an order of magnitude improvement compared to as-grown samples. An in-depth exploration of optical and spin dynamics reveals efficient spin polarization, coherent control, and readout with high fidelity (79%). We report T1 times greater than 1 s at cryogenic temperatures (15 K) with a T2* = 317 ns and a T2 = 81 μs, where spin dephasing times are currently limited by spin–spin interactions within the defect ensemble. Our results demonstrate the potential of Cr4+ in SiC as an extrinsic, optically active spin qubit.
Predicting Heart Failure Readmission from Clinical Notes Using Deep Learning

Heart failure hospitalization is a severe burden on healthcare. How to predict and therefore prevent readmission has been a significant challenge in outcomes research. To address this, we propose a deep learning approach to predict readmission from clinical notes. Unlike conventional methods that use structured data for prediction, we leverage the unstructured clinical notes to train deep learning models based on convolutional neural networks (CNN). We then use the trained models to classify and predict potentially high-risk admissions/patients. For evaluation, we trained CNNs using the discharge summary notes in the MIMIC III database. We also trained regular machine learning models based on random forest using the same datasets. The result shows that deep learning models outperform the regular models in prediction tasks. CNN method achieves a F1 score of 0.756 in general readmission prediction and 0.733 in 30-day readmission prediction, while random forest only achieves a F1 score of 0.674 and 0.656 respectively. We also propose a chi-square test based method to interpret key features associated with deep learning predicted readmissions. It reveals clinical insights about readmission embedded in the clinical notes. Collectively, our method can make the human evaluation process more efficient and potentially facilitate the reduction of readmission rates.
The Prism tableau model for Schubert polynomials

The Schubert polynomials lift the Schur basis of symmetric polynomials into a basis for Z[x1; x2; : : :]. We suggest the prism tableau model for these polynomials. A novel aspect of this alternative to earlier results is that it directly invokes semistandard tableaux; it does so as part of a colored tableau amalgam. In the Grassmannian case, a prism tableau with colors ignored is a semistandard Young tableau. Our arguments are developed from the Gr¨obner geometry of matrix Schubert varieties.
Dihedral sieving phenomena

Abstract Cyclic sieving is a well-known phenomenon where certain interesting polynomials, especially q -analogues, have useful interpretations related to actions and representations of the cyclic group. We propose a definition of sieving for an arbitrary group G and study it for the dihedral group I 2 ( n ) of order 2 n . This requires understanding the generators of the representation ring of the dihedral group. For n odd, we exhibit several instances of dihedral sieving which involve the generalized Fibonomial coefficients, recently studied by Amdeberhan, Chen, Moll, and Sagan. We also exhibit an instance of dihedral sieving involving Garsia and Haiman’s ( q , t ) -Catalan numbers.
A note on optimal sampling strategy for structural variant detection using optical mapping

Structural variants compose the majority of human genetic variation, but are difficult to accurately assess using current genomic sequencing technologies. Optical mapping technologies, which measur...
Assessing randomness with the aid of quantum state measurement

Randomness is a valuable resource in science, cryptography, engineering, and information technology. Quantum-mechanical sources of randomness are attractive because of the indeterminism of individual quantum processes. Here, we consider the production of random bits from polarization measurements on photons. We first present a pedagogical discussion of how the quantum randomness inherent in such measurements is connected to quantum coherence, and how it can be quantified in terms of the quantum state and an associated entropy value known as min-entropy. We then explore these concepts by performing a series of single-photon experiments that are suitable for the undergraduate laboratory. We prepare photons in different nonentangled and entangled states, and measure these states tomographically. We use the information about the quantum state to determine, in terms of the min-entropy, the minimum amount of randomness produced from a given photon state by different bit-generating measurements. This is helpful in assessing the presence of quantum randomness and in ensuring the quality and security of the random-bit source.
Simultaneous liquid flow and drying on rotating cylinders

A common model problem for discrete-object coating is the flow of a thin nonvolatile liquid film on the outside of a rotating cylinder. However, the behavior of a volatile particle-laden coating on rotating cylinders has yet to be studied and remains an important open problem. In this work, a lubrication-theory-based model is used to (i) examine the effects of various problem parameters on coating behavior, (ii) understand the underlying physical mechanisms, and (iii) provide guidance for improving coating uniformity.
Symmetry’s Mandate: Constraining the Politicization of American Administrative Law

Recent years have seen the rise of pointed and influential critiques of deference doctrines in administrative law. What many of these critiques have in common is a view that judges, not agencies, should resolve interpretive disputes over the meaning of statutes—disputes the critics take to be purely legal and almost always resolvable using lawyerly tools of statutory construction. In this Article, I take these critiques, and the relatively formalist assumptions behind them, seriously and show that the critics have not acknowledged or advocated the full reform vision implied by their theoretical premises. Specifically, critics have extended their critique of judicial abdication only to what I call Type I statutory errors (that is, agency interpretations that regulate more conduct than the best reading of the statute would allow the agency to regulate) and do not appear to accept or anticipate that their theory of interpretation would also extend to what I call Type II statutory errors (that is, agency failures to regulate as much conduct as the best reading of the statute would require). As a consequence, critics have been more than willing to entertain an end to Chevron deference, an administrative law doctrine that is mostly invoked to justify Type I error, but have not shown any interest in adjusting administrative law doctrine to remedy agencies’ commission of Type II error. The result is a vision of administrative law’s future that is precariously slanted against legislative and regulatory action. I critique this asymmetry in administrative law and address potential justifications of systemic asymmetries in the doctrine, such as concern about the remedial implications of addressing Type II error, finding them all wanting from a legal and theoretical perspective. I also lay out the positive case for adhering to symmetry in administrative law doctrine. In a time of deep political conflict over regulation and administration, symmetry plays, or at the very least could play, an important role in depoliticizing administrative law, clarifying what is at stake in debates about the proper level of deference to agency legal interpretations, and disciplining partisan gamesmanship. I suggest that when the conversation is so disciplined, an administrative law without deference to both Type I and Type II error is hard to imagine due to the high judicial costs of minimizing Type II error, but if we collectively choose to discard deference notwithstanding these costs, it would be a more sustainable political choice for administrative law than embracing the current, one-sided critique of deference.
Automatic Detection of Target Engagement in Transcutaneous Cervical Vagal Nerve Stimulation for Traumatic Stress Triggers

Transcutaneous cervical vagal nerve stimulation (tcVNS) devices are attractive alternatives to surgical implants, and can be applied for a number of conditions in ambulatory settings, including stress-related neuropsychiatric disorders. Transferring tcVNS technologies to at-home settings brings challenges associated with the assessment of therapy response. The ability to accurately detect whether tcVNS has been effectively delivered in a remote setting such as the home has never been investigated. We designed and conducted a study in which 12 human subjects received active tcVNS and 14 received sham stimulation in tandem with traumatic stress, and measured continuous cardiopulmonary signals including the electrocardiogram (ECG), photoplethysmogram (PPG), seismocardiogram (SCG), and respiratory effort (RSP). We extracted physiological parameters related to autonomic nervous system activity, and created a feature set from these parameters to: 1) detect active (vs. sham) tcVNS stimulation presence with machine learning methods, and 2) determine which sensing modalities and features provide the most salient markers of tcVNS-based changes in physiological signals. Heart rate (ECG), vasomotor activity (PPG), and pulse arrival time (ECG+PPG) provided sufficient information to determine target engagement (compared to sham) in addition to other combinations of sensors. resulting in 96% accuracy, precision, and recall with a receiver operator characteristics area of 0.96. Two commonly utilized sensing modalities (ECG and PPG) that are suitable for home use can provide useful information on therapy response for tcVNS. The methods presented herein could be deployed in wearable devices to quantify adherence for at-home use of tcVNS technologies.
Rapid online learning and robust recall in a neuromorphic olfactory circuit

We present a neural algorithm for the rapid online learning and identification of odourant samples under noise, based on the architecture of the mammalian olfactory bulb and implemented on the Intel Loihi neuromorphic system. As with biological olfaction, the spike timing-based algorithm utilizes distributed, event-driven computations and rapid (one shot) online learning. Spike timing-dependent plasticity rules operate iteratively over sequential gamma-frequency packets to construct odour representations from the activity of chemosensor arrays mounted in a wind tunnel. Learned odourants then are reliably identified despite strong destructive interference. Noise resistance is further enhanced by neuromodulation and contextual priming. Lifelong learning capabilities are enabled by adult neurogenesis. The algorithm is applicable to any signal identification problem in which high-dimensional signals are embedded in unknown backgrounds. Integrating knowledge about the circuit-level organization of the brain into neuromorphic artificial systems is a challenging research problem. The authors present a neural algorithm for the learning of odourant signals and their robust identification under noise, based on the architecture of the mammalian olfactory bulb and implemented on the Intel Loihi neuromorphic system.
Discovery as Regulation

This article develops an approach to discovery that is grounded in regulatory theory and administrative subpoena power. The conventional judicial and scholarly view about discovery is that it promotes fair and accurate outcomes and nudges the parties towards settlement. While commonly held, however, this belief is increasingly outdated and suffers from limitations. Among them, it has generated endless controversy about the problem of discovery costs. Indeed, a growing chorus of scholars and courts have offered an avalanche of reforms, from cost shifting and bespoke discovery contracts to outright elimination. Recently, Judge Thomas Hardiman quipped that if he had absolute power he would abolish discovery for cases involving less than $500,000. These debates, however, are at a standstill and existing scholarship offers incomplete treatment of discovery theory that might move debates forward. The core insight of the project is that in the private enforcement context — where Congress deliberately employs private litigants as the main method of statutory enforcement — there is a surprisingly strong case that our current discovery system should be understood in part as serving regulatory goals analogous to administrative subpoena power. That is, discovery here can be seen as an extension of the subpoena power that agencies like the SEC, FTC, and EPA possess and is the lynchpin of a system that depends on private litigants to enforce our most important statutes. By forcing parties to disclose large amounts of information, discovery deters harm and, most importantly, shapes industry-wide practices and the primary behavior of regulated entities. This approach has a vast array of implications for the scope of discovery as well as the debate over costs. Scholars and courts should thus grapple with the consequences of what I call “regulatory discovery” for the entire legal system.
Bayesian Factor Analysis for Inference on Interactions

This article is motivated by the problem of inference on interactions among chemical exposures impacting human health outcomes. Chemicals often co-occur in the environment or in synthetic mixtures ...
Why Do Competitive Markets Converge to First-Price Auctions?

We consider a setting in which bidders participate in multiple auctions run by different sellers, and optimize their bids for the aggregate auction. We analyze this setting by formulating a game between sellers, where a seller’s strategy is to pick an auction to run. Our analysis aims to shed light on the recent change in the Display Ads market landscape: here, ad exchanges (sellers) were mostly running second-price auctions earlier and over time they switched to variants of the first-price auction, culminating in Google’s Ad Exchange moving to a first-price auction in 2019. Our model and results offer an explanation for why the first-price auction occurs as a natural equilibrium in such competitive markets.
Molecular Signature of Pruriceptive MrgprA3+ Neurons.

Itch, initiated by the activation of sensory neurons, is associated frequently with dermatological diseases. MrgprA3+ sensory neurons have been identified as one of the major itch-sensing neuronal populations. Mounting evidence has demonstrated that peripheral pathological conditions induce physiological regulation of sensory neurons, which is critical for the maintenance of chronic itch sensation. However, the underlying molecular mechanisms are not clear. Here, we performed RNA sequencing of genetically labeled MrgprA3+ neurons under both naive and allergic contact dermatitis conditions. Our results revealed the unique molecular signature of itch-sensing neurons and the distinct transcriptional profile changes that result in response to dermatitis. We found enrichment of nine Mrgpr family members and two histamine receptors in MrgprA3+ neurons, suggesting that MrgprA3+ neurons are a direct neuronal target for histamine and Mrgpr agonists. In addition, PTPN6 and PCDH12 were identified as highly selective markers of MrgprA3+ neurons. We also discovered that MrgprA3+ neurons respond to skin dermatitis in a way that is unique from other sensory neurons by regulating a combination of transcriptional factors, ion channels, and key molecules involved in synaptic transmission. These results significantly increase our knowledge of itch transmission and uncover potential targets for combating itch.
High-efficiency fiber-to-chip interface for aluminum nitride quantum photonics

Integrated nonlinear photonic circuits received rapid development in recent years, providing all-optical functionalities enabled by cavity-enhanced photon-photon interaction for classical and quantum applications. A high-efficiency fiber-to-chip interface is key to these integrated photonic circuits for quantum information tasks, as photon-loss is a major source that weakens quantum protocols. Here, overcoming material and fabrication limitation of thin-film aluminum nitride by adopting a stepwise waveguiding scheme, we demonstrate low-loss adiabatic fiber-optic couplers in aluminum nitride films with a substantial thickness (∼600 nm) for optimized nonlinear photon interaction. For telecom (1550 nm) and near-visible (780 nm) transverse magnetic-polarized light, the measured insertion loss of the fiber-optic coupler is -0.97 dB and -2.6 dB, respectively. Our results will facilitate the use of aluminum nitride integrated photonic circuits as efficient quantum resources for generation of entangled photons and squeezed light on microchips.
ASE Statement on Protection of Patients and Echocardiography Service Providers During the 2019 Novel Coronavirus Outbreak: Endorsed by the American College of Cardiology.

Highlights • ASE guidance for patient and provider protection during echo exams in the COVID-19 pandemic. • Triaging approach for prioritizing echo exams during the COVID-19 pandemic. • Recommended...
Deliberation and Discussion in Classical Athens

Deliberative democracy has often been associated with classical Athens, yet how far and where such activity appeared in the classical Athenian political system is open to question. This article explores the character of the deliberation and/or discussion that took place in five Athenian political arenas: courts, assembly, council, local assemblies, and street. It finds that in democratic Athens, discussion and deliberation (in the core Greek sense of “coming to a decision”) were inversely related. The most decisive arenas (assembly, courts) were the least discursive, in the sense of being least marked by the exchange of reasons admired by many contemporary theorists, while the most discursive arenas (street, perhaps local assemblies, perhaps council) were the least decisive. This finding makes sense. Mass democracy relies ultimately on the vote, not on back-and-forth discussion. Yet does not follow that discussion was unimportant to Athenian democracy. Indeed, it seems very likely (though impossible to prove or to disprove) that the decision-making powers of ordinary citizens in the assembly and courts prompted increased discussion of political issues outside those bodies, and that such “everyday talk” affected votes.
MAC Protocol Design Optimization Using Deep Learning

Deep learning (DL)-based solutions have recently been developed for communication protocol design. Such learning-based solutions can avoid manual efforts to tune individual protocol parameters. While these solutions look promising, they are hard to interpret due to the black-box nature of the ML techniques. To this end, we propose a novel DRL-based framework to systematically design and evaluate networking protocols. While other proposed ML-based methods mainly focus on tuning individual protocol parameters (e.g., adjusting contention window), our main contribution is to decouple a protocol into a set of parametric modules, each representing a main protocol functionality and is used as DRL input to better understand the generated protocols design optimization and analyze them in a systematic fashion. As a case study, we introduce and evaluate DeepMAC a framework in which a MAC protocol is decoupled into a set of blocks across popular flavors of 802.11 WLANs (e.g., 802.11a/b/g/n/ac). We are interested to see what blocks are selected by DeepMAC across different networking scenarios and whether DeepMAC is able to adapt to network dynamics.
A theory of pre-filing settlement and patent assertion entities

Abstract An informed (prospective) plaintiff can send a take-it-or-leave-it demand to an uninformed (prospective) defendant with the threat of a lawsuit that may not be credible. In this context, the well-known perfect separating equilibrium in litigation bargaining game (Reinganum and Wilde, 1986) no longer exists, and all perfect Bayesian equilibria with pre-filing settlements exhibit a cutoff feature. These equilibria offer an explanation for the distinctive behaviors of Litigation PAEs, who aggressively file lawsuits for settlements, and Portfolio PAEs, who obtain licensing revenues through pre-filing settlements. Our comparative statics results lead to testable hypotheses regarding how litigation costs and the plaintiff’s reputation affect the settlement amount before and after the cases are filed, and the frequency of lawsuits from a given plaintiff.
GiniClust3: a fast and memory-efficient tool for rare cell type identification

With the rapid development of single-cell RNA sequencing technology, it is possible to dissect cell-type composition at high resolution. A number of methods have been developed with the purpose to identify rare cell types. However, existing methods are still not scalable to large datasets, limiting their utility. To overcome this limitation, we present a new software package, called GiniClust3, which is an extension of GiniClust2 and significantly faster and memory-efficient than previous versions. Using GiniClust3, it only takes about 7 h to identify both common and rare cell clusters from a dataset that contains more than one million cells. Cell type mapping and perturbation analyses show that GiniClust3 could robustly identify cell clusters. Taken together, these results suggest that GiniClust3 is a powerful tool to identify both common and rare cell population and can handle large dataset. GiniCluster3 is implemented in the open-source python package and available at https://github.com/rdong08/GiniClust3.
Privacy-Preserving Biomedical Database Queries with Optimal Privacy-Utility Trade-Offs.

Sharing data across research groups is an essential driver of biomedical research. In particular, biomedical databases with interactive query-answering systems allow users to retrieve information from the database using restricted types of queries. For example, medical data repositories allow researchers designing clinical studies to query how many patients in the database satisfy certain criteria, a workflow known as cohort discovery. In addition, genomic “beacon” services allow users to query whether or not a given genetic variant is observed in the database, a workflow we refer to as variant lookup. While these systems aim to facilitate the sharing of aggregate biomedical insights without divulging sensitive individual-level data, they can still leak private information about the individuals through the query answers. To address these privacy concerns, existing studies have proposed to perturb query results with a small amount of noise in order to reduce sensitivity to underlying individuals [1, 2]. However, these existing efforts either lack rigorous guarantees of privacy or introduce an excessive amount of noise into the system, limiting their effectiveness in practice.
Review of 20 years of range sensor development

We review 20 years of development in the field of 3-D laser imaging. An overview of 3-D digitizing techniques is presented with an emphasis on commercial techniques and systems currently available. It covers some of the most important methods that have been developed, both at the National Research Council of Canada (NRC) and elsewhere, with a focus on commercial systems that are considered good representations of the key technologies that have survived the test of years. © 2004 SPIE and IS&T.
Competition in large markets

This paper develops a simple and robust implication of free entry followed by competition without substantial strategic interactions: Increasing the number of consumers leaves the distributions of producers' prices and other choices unchanged. In many models featuring non-trivial strategic considerations, producers' prices fall as their numbers increase. Hence, examining the relationship between market size and producers' actions provides a nonparametric tool for empirically discriminating between these distinct approaches to competition. To illustrate its application, I examine observations of restaurants' seating capacities, exit decisions, and prices from 224 U.S. cities. Given factor prices and demographic variables, increasing a city's size increases restaurants' capacities, decreases their exit rate, and decreases their prices. These results suggest that strategic considerations lie at the heart of restaurant pricing and turnover.
Cyanide antidotes and fire toxicology

Smoke is a heterogeneous mixture of particulate matter (carbon particles coated with acids, aldehydes, and acroleins) and heated gases. The gases can be generally classified as irritants, such as h...
Misreporting Trade: Tariff Evasion, Corruption, and Auditing Standards

Official international trade statistics report commerce between every pair of countries twice: once for the importing country and once for the exporter. In principle, the two values differ only by transport costs, but as has long been recognized, they also differ systematically with product‐level tariffs. We aggregate across products to construct a dataset of annual aggregate bilateral trade, separately for the importer and exporter reports. With these data, we show that the reporting differences also vary systematically with country characteristics aside from tariffs: incomes, auditing standards, corruption, and trade agreements.
Chapter 5 – Reproductive Modes

Beginning with definitions, which differ for amphibians and reptiles, the remarkable diversity of reproductive modes is described, and many examples are given. A considerable number of amphibians have direct development, in which no larval stage exists. Recently, the taxon Orthobatrachia was proposed to unite all New World direct-developing frogs; this taxon, consisting of over 1000 species, comprises 73% of direct-developing frogs in the world. Although most species are oviparous, viviparity exists in some amphibians, especially caecilians, but the greatest number of independent origins of viviparity exists in squamate reptiles. Parental care occurs in many species, varies considerably among species, and is extended in some. The evolution of parental care is discussed in detail.
A Forensic Analysis of Global Imbalances

We examine whether the behavior of current account balances changed in the years preceding the global crisis of 2008-09, and assess the prospects for global imbalances in the post-crisis period. Changes in the budget balance are an important factor affecting current account balances for deficit countries such as the U.S. and the U.K. The effect of the "saving glut variables" on current account balances has been relatively stable for emerging market countries, suggesting that those factors cannot explain the bulk of their recent current account movements. We also find the 2006-08 period to constitute a structural break for emerging market countries, and to a lesser extent, for industrialized countries. We attribute the anomalous behavior of pre-crisis current account balances to stock market performance and real housing appreciation; fiscal procyclicality and the stance of monetary policy do not matter as much. Household leverage also appears to explain some of the standard model's prediction errors. Looking forward, U.S., fiscal consolidation alone cannot induce significant deficit reduction. For China, financial development might help shrink its current account surplus, but only when it is coupled with financial liberalization. These findings suggest that unless countries implement substantially more policy change, global imbalances are unlikely to disappear.