cssi/SciSciGPT-SciSciNet huggingface dataset:
Utilizing transcranial direct current stimulation to enhance laparoscopic technical skills training: A randomized controlled trial.

Abstract Background Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that delivers constant, low electrical current resulting in changes to cortical excitability. Prior work suggests it may enhance motor learning giving it the potential to augment surgical technical skill acquisition. Objectives The aim of this study was to test the efficacy of tDCS, coupled with motor skill training, to accelerate laparoscopic skill acquisition in a pre-registered (NCT03083483), double-blind and placebo-controlled study. We hypothesized that relative to sham tDCS, active tDCS would accelerate the development of laparoscopic technical skills, as measured by the Fundamentals of Laparoscopic Surgery (FLS) Peg Transfer task quantitative metrics. Methods In this study, sixty subjects (mean age 22.7 years with 42 females) were randomized into sham or active tDCS in either bilateral primary motor cortex (bM1) or supplementary motor area (SMA) electrode configurations. All subjects practiced the FLS Peg Transfer Task during six 20-min training blocks, which were preceded and followed by a single trial pre-test and post-test. The primary outcome was changes in laparoscopic skill performance over time, quantified by group differences in completion time from pre-test to post-test and learning curves developed from a calculated score accounting for errors. Results Learning curves calculated over the six 20-min training blocks showed significantly greater improvement in performance for the bM1 group than the sham group (t = 2.07, p = 0.039), with the bM1 group achieving approximately the same amount of improvement in 4 blocks compared to the 6 blocks required of the sham group. The SMA group also showed greater mean improvement than sham, but exhibited more variable learning performance and differences relative to sham were not significant (t = 0.85, p = 0.400). A significant main effect was present for pre-test versus post-test times (F = 133.2, p Conclusion Laparoscopic skill training with active bilateral tDCS exhibited significantly greater learning relative to sham. The potential for tDCS to enhance the training of surgical skills, therefore, merits further investigation to determine if these preliminary results may be replicated and extended.
Sample Compression, Support Vectors, and Generalization in Deep Learning

Even though Deep Neural Networks (DNNs) are widely celebrated for their practical performance, they possess many intriguing properties related to depth that are difficult to explain both theoretically and intuitively. Understanding how weights in deep networks coordinate together across layers to form useful learners has proven challenging, in part because the repeated composition of nonlinearities has proved intractable. This paper presents a reparameterization of DNNs as a linear function of a feature map that is locally independent of the weights. This feature map transforms depth-dependencies into simple tensor products and maps each input to a discrete subset of the feature space. Then, using a max-margin assumption, the paper develops a sample compression representation of the neural network in terms of the discrete activation state of neurons induced by $s$ “support vectors”. The paper shows that the number of support vectors $s$ relates with learning guarantees for neural networks through sample compression bounds, yielding a sample complexity of $\mathcal {O}(ns/\epsilon)$ for networks with $n$ neurons. Finally, the number of support vectors $s$ is found to monotonically increase with width and label noise but decrease with depth.
Target Membrane Cholesterol Modulates Single Influenza Virus Membrane Fusion Efficiency but Not Rate.

Host lipid composition influences many stages of the influenza A virus (IAV) entry process, including initial binding of IAV to sialylated glycans, fusion between the viral envelope and the host membrane, and the formation of a fusion pore through which the viral genome is transferred into a target cell. In particular, target membrane cholesterol has been shown to preferentially associate with virus receptors and alter physical properties of the membrane like fluidity and curvature. These properties affect both IAV binding and fusion, which makes it difficult to isolate the role of cholesterol in IAV fusion from receptor binding effects. Here, we develop a fusion assay that uses synthetic DNA-lipid conjugates as surrogate viral receptors to tether virions to target vesicles. To avoid the possibly perturbative effect of adding a self-quenched concentration of dye-labeled lipids to the viral membrane, we tether virions to lipid-labeled target vesicles and use fluorescence microscopy to detect individual, pH-triggered IAV membrane fusion events. Through this approach, we find that cholesterol in the target membrane enhances the efficiency of single-particle IAV lipid mixing, whereas the rate of lipid mixing is independent of cholesterol composition. We also find that the single-particle kinetics of influenza lipid mixing to target membranes with different cholesterol compositions is independent of receptor binding, suggesting that cholesterol-mediated spatial clustering of viral receptors within the target membrane does not significantly affect IAV hemifusion. These results are consistent with the hypothesis that target membrane cholesterol increases lipid mixing efficiency by altering host membrane curvature.
Self-heterodyned detection of dressed state coherences in helium by noncollinear extreme ultraviolet wave mixing with attosecond pulses

Author(s): Fidler, AP; Warrick, ER; Marroux, HJB; Bloch, E; Neumark, DM; Leone, SR | Abstract: Noncollinear wave-mixing spectroscopies with attosecond extreme ultraviolet (XUV) pulses provide unprecedented insight into electronic dynamics. In infrared and visible regimes, heterodyne detection techniques utilize a reference field to amplify wave-mixing signals while simultaneously allowing for phase-sensitive measurements. Here, we implement a self-heterodyned detection scheme in noncollinear wave-mixing measurements with a short attosecond XUV pulse train and two few-cycle near infrared (NIR) pulses. The initial spatiotemporally overlapped XUV and NIR pulses generate a coherence of both odd (1snp) and even (1sns and 1snd) parity states within gaseous helium. A variably delayed noncollinear NIR pulse generates angularly-dependent four-wave mixing signals that report on the evolution of this coherence. The diffuse angular structure of the XUV harmonics underlying these emission signals is used as a reference field for heterodyne detection, leading to cycle oscillations in the transient wave-mixing spectra. With this detection scheme, wave-mixing signals emitting from at least eight distinct light-induced, or dressed, states can be observed, in contrast to only one light induced state identified in a similar homodyne wave-mixing measurement. In conjunction with the self-heterodyned detection scheme, the noncollinear geometry permits the conclusive identification and angular separation of distinct wave-mixing pathways, reducing the complexity of transient spectra. These results demonstrate that the application of heterodyne detection schemes can provide signal amplification and phase-sensitivity, while maintaining the versatility and selectivity of noncollinear attosecond XUV wave-mixing spectroscopies. These techniques will be important tools in the study of ultrafast dynamics within complex chemical systems in the XUV regime.
On the uniqueness of functions that maximize the Crouzeix ratio

Abstract Let A be an n by n matrix with numerical range W ( A ) : = { q ⁎ A q : q ∈ C n , ‖ q ‖ 2 = 1 } . We are interested in functions f ˆ that maximize ‖ f ( A ) ‖ 2 (the matrix norm induced by the vector 2-norm) over all functions f that are analytic in the interior of W ( A ) and continuous on the boundary and satisfy max z ∈ W ( A ) ⁡ | f ( z ) | ≤ 1 . It is known that there are functions f ˆ that achieve this maximum and that such functions are of the form B ∘ ϕ , where ϕ is any conformal mapping from the interior of W ( A ) to the unit disk D , extended to be continuous on the boundary of W ( A ) , and B is a Blaschke product of degree at most n − 1 . It is not known if a function f ˆ that achieves this maximum is unique, up to multiplication by a scalar of modulus one. We show that this is the case when A is a 2 × 2 nonnormal matrix or a Jordan block, but we give examples of some 3 × 3 matrices with elliptic numerical range for which two different functions f ˆ , involving the same conformal mapping but Blaschke products of different degrees, achieve the same maximal value of | | f ( A ) | | 2 .
Floodings of metric graphs

We consider random labelings of finite graphs conditioned on a small fixed number of peaks. We introduce a continuum framework where a combinatorial graph is associated with a metric graph and edges are identified with intervals. Next we consider a sequence of partitions of the edges of the metric graph with the partition size going to zero. As the mesh of the subdivision goes to zero, the conditioned random labelings converge, in a suitable sense, to a deterministic function which evolves as an increasing process of subsets of the metric graph that grows at rate one while maximizing an appropriate notion of entropy. We call such functions floodings. We present a number of qualitative and quantitative properties of floodings and some explicit examples.
Ensemble modeling of auditory streaming reveals potential sources of bistability across the perceptual hierarchy.

Perceptual bistability—the spontaneous, irregular fluctuation of perception between two interpretations of a stimulus—occurs when observing a large variety of ambiguous stimulus configurations. This phenomenon has the potential to serve as a tool for, among other things, understanding how function varies across individuals due to the large individual differences that manifest during perceptual bistability. Yet it remains difficult to interpret the functional processes at work, without knowing where bistability arises during perception. In this study we explore the hypothesis that bistability originates from multiple sources distributed across the perceptual hierarchy. We develop a hierarchical model of auditory processing comprised of three distinct levels: a Peripheral, tonotopic analysis, a Central analysis computing features found more centrally in the auditory system, and an Object analysis, where sounds are segmented into different streams. We model bistable perception within this system by applying adaptation, inhibition and noise into one or all of the three levels of the hierarchy. We evaluate a large ensemble of variations of this hierarchical model, where each model has a different configuration of adaptation, inhibition and noise. This approach avoids the assumption that a single configuration must be invoked to explain the data. Each model is evaluated based on its ability to replicate two hallmarks of bistability during auditory streaming: the selectivity of bistability to specific stimulus configurations, and the characteristic log-normal pattern of perceptual switches. Consistent with a distributed origin, a broad range of model parameters across this hierarchy lead to a plausible form of perceptual bistability.
REPIC: a database for exploring the N 6 -methyladenosine methylome.

The REPIC (RNA EPItranscriptome Collection) database records about 10 million peaks called from publicly available m6A-seq and MeRIP-seq data using our unified pipeline. These data were collected from 672 samples of 49 studies, covering 61 cell lines or tissues in 11 organisms. REPIC allows users to query N6-methyladenosine (m6A) modification sites by specific cell lines or tissue types. In addition, it integrates m6A/MeRIP-seq data with 1418 histone ChIP-seq and 118 DNase-seq data tracks from the ENCODE project in a modern genome browser to present a comprehensive atlas of m6A methylation sites, histone modification sites, and chromatin accessibility regions. REPIC is accessible at https://repicmod.uchicago.edu/repic.
Transmission Expansion Planning with Seasonal Network Optimization

Transmission expansion planning (TEP) is critical for the power grid to meet fast growing demand in the future. Traditional TEP model does not utilize the flexibility in the transmission network that is considered as static assets. However, as the load profile may have different seasonal patterns, the optimal network configuration could be very different for different seasons in the planning horizon. Therefore, this paper proposes to incorporate seasonal network optimization (SNO) into the traditional TEP model. SNO dynamically optimizes the network for each season of each planning epoch. Two TEP-SNO models are proposed to investigate the benefits of optimizing the status of (i) existing branches, and (ii) existing and new branches, respectively. Numerical simulations demonstrate the effectiveness of the proposed TEP-SNO models. It is shown that SNO can improve system operational efficiency, defer investment of new transmission elements, and reduce the total cost.
Corporate Governance over the Business Cycle

Abstract I provide empirical evidence that badly governed firms respond more to aggregate shocks than do well governed firms. I build a simple model where managers are prone to over-invest and where shareholders are more likely to tolerate such a behavior in good times. The model successfully explains the average profit differences as well as the cyclical behavior of sales, employment and investment for firms with different governance qualities. The quantitative results suggest that governance conflicts could explain up to a third of aggregate volatility.
Deep phenotyping of cardiac function in heart transplant patients using cardiovascular systems models

Key points: Right heart catheterization (RHC) data from clinical records of heart transplant patients are used to identify patient specific models of the cardiovascular system These patient specific cardiovascular models represent a snapshot of cardiovascular function at a given post-transplant recovery timepoint. This approach is used to describe cardiac function in ten heart transplant patients, five of which had multiple right heart catheterizations allowing an assessment of cardiac function over time. These patient predict cardiovascular function in the form of right and left ventricular pressure-volume loops and ventricular power, an important metrics in the clinic of cardiac function. Outcomes for the longitudinally tracked patients shows that our approach was able to identify the one patient from the group of five that exhibited post-transplant cardiovascular complications. Abstract: Heart transplant patients are followed with periodic right heart catheterizations (RHCs) to identify post-transplant complications and guide treatment. Post-transplant positive outcomes are associated with a steady reduction of right ventricular and pulmonary arterial pressures, toward normal levels of right-side pressure (about 20 mmHg) measured by RHC. This study shows more information about patient progression is obtained by combining standard RHC measures with mechanistic computational cardiovascular systems models. The purpose of this study is two-fold: to understand how cardiovascular system models can be used to represent a patient's cardiovascular state, and to use these models to track post-transplant recovery and outcome. To obtain reliable parameter estimates comparable within and across datasets, we use sensitivity analysis, parameter subset selection, and optimization to determine patient specific mechanistic parameter that can be reliably extracted from the RHC data. Patient-specific models are identified for ten patients from their first post-transplant RHC and longitudinal analysis is done for five patients. Results of sensitivity analysis and subset selection show we can reliably estimate seven non-measurable quantities including ventricular diastolic relaxation, systemic resistance, pulmonary venous elastance, pulmonary resistance, pulmonary arterial elastance, pulmonary valve resistance and systemic arterial elastance. Changes in parameters and predicted cardiovascular function post-transplant are used to evaluate cardiovascular state during recovery in five patients. Of these five patients, only one patient showed inconsistent trends during recovery in ventricular pressure-volume relationships and power output. At the four-year post-transplant time point this patient exhibited biventricular failure along with graft dysfunction while the remaining four exhibited no cardiovascular complications. This article is protected by copyright. All rights reserved.
The Influence of Ancestral Lifeways on Individual Economic Outcomes in Sub-Saharan Africa

Does a person's historical lineage influence his or her current economic status? Motivated by a large literature in social sciences stressing the effect of an early transition to agriculture on current economic performance at the level of countries, we examine the relative contemporary status of individuals as a function of how much their ancestors relied on agriculture during the pre-industrial era. We focus on Africa, where by combining anthropological records of groups with individual level survey data we can explore the effect of the historical lifeways of one's forefathers. Within enumeration areas and occupational groups, we find that individuals from ethnicities that derived a larger share of subsistence from agriculture in the precolonial era are today more educated and wealthy. A tentative exploration of channels suggests that differences in attitudes and beliefs as well as differential treatment by others, including differential political power, may contribute to these divergent outcomes.
The external environment‐strategic planning interface: U.S. multinational corporate practices in the 1980s

This paper presents data collected by structured interviews concerning how external environment analysis and strategic planning are related in major U.S.-based multinational corporations. The research was also undertaken to ascertain why and the extent to which firms have formally institutionalized the external environmental functions since the Iranian revolution.
Symplectic cohomology rings of affine varieties in the topological limit

We construct a multiplicative spectral sequence converging to the symplectic cohomology ring of any affine variety X, with first page built out of topological invariants associated to strata of any fixed normal crossings compactification $$(M,{\mathbf {D}})$$ of X. We exhibit a broad class of pairs $$(M,{\mathbf {D}})$$ (characterized by the absence of relative holomorphic spheres or vanishing of certain relative GW invariants) for which the spectral sequence degenerates, and a broad subclass of pairs (similarly characterized) for which the ring structure on symplectic cohomology can also be described topologically. Sample applications include: (a) a complete topological description of the symplectic cohomology ring of the complement, in any projective M, of the union of sufficiently many generic ample divisors whose homology classes span a rank one subspace, (b) complete additive and partial multiplicative computations of degree zero symplectic cohomology rings of many log Calabi-Yau varieties, and (c) a proof in many cases that symplectic cohomology is finitely generated as a ring. A key technical ingredient in our results is a logarithmic version of the PSS morphism, introduced in our earlier work Ganatra and Pomerleano, arXiv:1611.06849.
Role of Synaptic Inhibition in the Coupling of the Respiratory Rhythms that Underlie Eupnea and Sigh Behaviors.

The preBotzinger complex (preBotC) gives rise to two types of breathing behavior under normal physiological conditions: eupnea and sighing. Here, we examine the neural mechanisms that couple their underlying rhythms. We measured breathing in awake intact adult mice and recorded inspiratory rhythms from the preBotC in neonatal mouse brainstem slice preparations. We show previously undocumented variability in the temporal relationship between sigh breaths or bursts and their preceding eupneic breaths or inspiratory bursts. Investigating the synaptic mechanisms for this variability in vitro, we further show that pharmacological blockade of chloride-mediated synaptic inhibition strengthens inspiratory-to-sigh temporal coupling. These findings contrast with previous literature, which suggested glycinergic inhibition linked sigh bursts to their preceding inspiratory bursts with minimal time intervals. Furthermore, we verify that pharmacological disinhibition did not alter the duration of the prolonged interval that follows a sigh burst before resumption of the inspiratory rhythm. These results demonstrate that synaptic inhibition does not enhance coupling between sighs and preceding inspiratory events or contribute to post-sigh apneas. Instead, we conclude that excitatory synaptic mechanisms coordinate inspiratory (eupnea) and sigh rhythms.
WORKPLACE INCIVILITY EXPERIENCED BY HEALTH ADMINISTRATION FACULTY

Workplace incivility is low-intensity, nonspecific, discourteous behavior towards others and may negatively affect employee and organizational outcomes. This exploratory study sought to examine the prevalence of and factors related to experiencing several different types of workplace incivility using a national sample of Health Administration full-time faculty members in the United States. We found that 27-36% of respondents have experienced at least one type of uncivil behavior from students, coworkers, or supervisors. Further, 4-9% of faculty respondents experience such incidents frequently. Faculty respondents who experienced workplace incivility were significantly more likely to report lower job satisfaction and indicated an intention to leave their position within the next three years. Academic leaders should work to foster an environment where incivility towards others is actively discouraged, as it may contribute to dissatisfaction and turnover.
Renovascular hypertension secondary to renal artery compression by diaphragmatic crura.

Abstract Median arcuate ligament syndrome is the result of celiac axis compression by the diaphragmatic crura. Although the celiac artery is the most common vessel to have compression, the renal arteries may also rarely be compressed by the crural fibers of the diaphragm, which may cause secondary hypertension. We present two cases of renovascular hypertension secondary to renal artery compression by the diaphragmatic crura. The first patient was treated with open decompression and wide resection of the crural fibers, and the second patient was decompressed laparoscopically. Neither case required renal artery reconstruction. Antihypertensives were discontinued in both patients postoperatively.
Changing the Subject of Sati

On November 11, 1999, in a small village in India’s most populous state, a middle-aged woman named Charan Shah died on her husband’s funeral pyre. Charan’s death quickly gained national notoriety as the first sati, or widow immolation, to occur in over 20 years. Equally quickly, commentators developed a preoccupation with procedural minutiae that would influence coverage of subsequent satis. Ultimately, several progressive commentators came to the counterintuitive conclusion that the ritually anomalous nature of Charan’s death confirmed its voluntary, secular, and non-criminal nature. This paper argues that the “un-labeling” of Charan Shah’s death, like those of other women between 1999–2006, reflects a tension between the non-individuated, impervious model of personhood exemplified by sati and the particularized citizen-subject of liberal-democratic politics in India. In a twist on “recognition” scholarship, both state and non-state critics seem to fear (not yearn for) a return to idealized notions of precolonial authenticity. Their perplexing responses to seemingly “authentic” contemporary immolations suggest that something more than cultural authenticity or gendered agency places sati beyond the comprehension of liberalism and its legal forms. That something is the inability of liberal-democratic politics and the legal infrastructure to which it gives rise to accommodate alternative models of personhood.
Election by Community Consensus: Effects on Political Selection and Governance

This paper evaluates the effects of encouraging the selection of local politicians in India via community consensus, as opposed to a secret ballot election. Using village-level data on candidates, ...
Estimating the number and effect sizes of non-null hypotheses

We study the problem of estimating the distribution of effect sizes (the mean of the test statistic under the alternate hypothesis) in a multiple testing setting. Knowing this distribution allows us to calculate the power (type II error) of any experimental design. We show that it is possible to estimate this distribution using an inexpensive pilot experiment, which takes significantly fewer samples than would be required by an experiment that identified the discoveries. Our estimator can be used to guarantee the number of discoveries that will be made using a given experimental design in a future experiment. We prove that this simple and computationally efficient estimator enjoys a number of favorable theoretical properties, and demonstrate its effectiveness on data from a gene knockout experiment on influenza inhibition in Drosophila.
On the iterated Hamiltonian Floer homology

The focus of the paper is the behavior under iterations of the filtered and local Floer homology of a Hamiltonian on a symplectically aspherical manifold. The Floer homology of an iterated Hamilton...
A non-nuclear $$C^*$$-algebra with the weak expectation property and the local lifting property

We construct the first example of a $$C^*$$ -algebra A with the properties in the title. This gives a new example of non-nuclear A for which there is a unique $$C^*$$ -norm on $$A \otimes A^{op}$$ . This example is of particular interest in connection with the Connes–Kirchberg problem, which is equivalent to the question whether $$C^*({\mathbb {F}}_2)$$ , which is known to have the LLP, also has the WEP. Our $$C^*$$ -algebra A has the same collection of finite dimensional operator subspaces as $$C^*({\mathbb {F}}_2)$$ or $$C^*({\mathbb {F}}_\infty )$$ . In addition our example can be made to be quasidiagonal and of similarity degree (or length) 3. In the second part of the paper we reformulate our construction in the more general framework of a $$C^*$$ -algebra that can be described as the limit both inductive and projective for a sequence of $$C^*$$ -algebras $$(C_n)$$ when each $$C_n$$ is a subquotient of $$C_{n+1}$$ . We use this to show that for certain local properties of injective (non-surjective) $$*$$ -homomorphisms, there are $$C^*$$ -algebras for which the identity map has the same properties as the $$*$$ -homomorphisms.
The impacts of fintech on small business borrowing

Consolidation in banking raise concerns about exclusion and predatory practices in small-business lending. Fintech lenders, largely unregulated credit providers with lending decisions and loan term...
Identification of multiple large deletions in ORF7a resulting in in-frame gene fusions in clinical SARS-CoV-2 isolates.

Peculiar among human RNA viruses, coronaviruses have large genomes containing accessory genes that are not required for replication. Numerous mutations within the SARS-CoV-2 genome have been described but few deletions in the accessory genes of SARS-CoV-2 have been reported. Here, we report two large deletions in ORF7a, both of which produce new open reading frames (ORFs) through the fusion of the N-terminus of ORF7a and a downstream ORF.
Antiviral Drug Screen of Kinase inhibitors Identifies Cellular Signaling Pathways Critical for SARS-CoV-2 Replication

Emergence of a highly contagious novel coronavirus, SARS-CoV-2 that causes COVID-19, has precipitated the current global health crisis with over 479,000 deaths and more than 9.3 million confirmed cases. Currently, our knowledge of the mechanisms of COVID-19 disease pathogenesis is very limited which has hampered attempts to develop targeted antiviral strategies. Therefore, we urgently need an effective therapy for this unmet medical need. Viruses hijack and dysregulate cellular machineries in order for them to replicate and infect more cells. Thus, identifying and targeting dysregulated signaling pathways that have been taken over by viruses is one strategy for developing an effective antiviral therapy. We have developed a high-throughput drug screening system to identify potential antiviral drugs targeting SARS-CoV-2. We utilized a small molecule library of 430 protein kinase inhibitors, which are in various stages of clinical trials. Most of the tested kinase antagonists are ATP competitive inhibitors, a class of nucleoside analogs, which have been shown to have potent antiviral activity. From the primary screen, we have identified 34 compounds capable of inhibiting viral cytopathic effect in epithelial cells. Network of drug and protein relations showed that these compounds specifically targeted a limited number of cellular kinases. More importantly, we have identified mTOR-PI3K-AKT, ABL-BCR/MAPK, and DNA-Damage Response (DDR) pathways as key cellular signaling pathways critical for SARS-CoV-2 infection. Subsequently, a secondary screen confirmed compounds such as Berzosertib (VE-822), Vistusertib (AZD2014), and Nilotinib with anti SARS-CoV-2 activity. Finally, we found that Berzosertib, an ATR kinase inhibitor in the DDR pathway, demonstrated potent antiviral activity in a human epithelial cell line and human induced pluripotent stem cell (hIPSC)-derived cardiomyocytes. These inhibitors are already in clinical trials of phase 2 or 3 for cancer treatment, and can be repurposed as promising drug candidates for a host-directed therapy of SARS-CoV-2 infection. In conclusion, we have identified small molecule inhibitors exhibiting anti SARS-CoV-2 activity by blocking key cellular kinases, which gives insight on important mechanism of host-pathogen interaction. These compounds can be further evaluated for the treatment of COVID-19 patients following additional in vivo safety and efficacy studies.
Covid-19: Macroeconomic impacts and policy issues in India

This editorial discusses the potential short, and long-run macroeconomic impacts of COVID-19 in India, presents early evidence of some of these effects and examines policy issues that would be important in the coming days. Since the Indian economy was experiencing sluggish growth on the eve of the COVID-19 outbreak, the economic downturn could be severe, and the policy intervention would require a careful weighing of options and priorities. Given that policy space and resources are limited, policies that help manage the short-run crisis and yield significant long-run benefits should receive serious consideration.
Degree bounds for local cohomology

Let R be a non-negatively graded Cohen-Macaulay ring with R_0 a Cohen-Macaulay factor ring of a local Gorenstein ring. Let d be the dimension of R, m be the maximal homogeneous ideal of R, and M be a finitely generated graded R-module. It has long been known how to read information about the socle degrees of the local cohomology module H_m^0(M) from the twists in position d in a resolution of M by free R-modules. It has also long been known how to use local cohomology to read valuable information from complexes which approximate resolutions in the sense that they have positive homology of small Krull dimension. The present paper reads information about the maximal generator degree (rather than the socle degree) of H_m^0M from the twists in position d-1 (rather than position d) in an approximate resolution of M. We apply the local cohomology results to draw conclusions about the maximum generator degree of the second symbolic power of the prime ideal defining a monomial curve and the second symbolic power of the ideal defining a finite set of points in projective space. There is an application to general hyperplane sections of subschemes of projective space over an infinite field. There is an application of the local cohomology techniques to partial Castelnuovo-Mumford regularity. An application to the ideals generated by the lower order Pfaffians of an alternating matrix will appear in a future paper. One additional application to the study of blow-up algebras appears in a separate paper.
Vision-Based Autonomous Driving: A Model Learning Approach.

We present an integrated approach for perception and control for an autonomous vehicle and demonstrate this approach in a high-fidelity urban driving simulator. Our approach first builds a model for the environment, then trains a policy exploiting the learned model to identify the action to take at each time-step. To build a model for the environment, we leverage several deep learning algorithms. To that end, first we train a variational autoencoder to encode the input image into an abstract latent representation. We then utilize a recurrent neural network to predict the latent representation of the next frame and handle temporal information. Finally, we utilize an evolutionary-based reinforcement learning algorithm to train a controller based on these latent representations to identify the action to take. We evaluate our approach in CARLA, a high-fidelity urban driving simulator, and conduct an extensive generalization study. Our results demonstrate that our approach outperforms several previously reported approaches in terms of the percentage of successfully completed episodes for a lane keeping task.
Low Correlation Noise Stability of Symmetric Sets

We study the Gaussian noise stability of subsets A of Euclidean space satisfying $$A=-A$$ . It is shown that an interval centered at the origin, or its complement, maximizes noise stability for small correlation, among symmetric subsets of the real line of fixed Gaussian measure. On the other hand, in dimension two and higher, the ball or its complement does not always maximize noise stability among symmetric sets of fixed Gaussian measure. In summary, we provide the first known positive and negative results for the symmetric Gaussian problem.
Fabrication of Luminescent Porous Silicon with Stain Etches and Evidence that Luminescence Originates in Amorphous Layers

Stain films on Si wafers produced in solutions of HF:HNO 3 :H 2 O have been studied for over 30 years [1], and have been suggested [1] to be similar in nature to the anodically-etched porous Si films first demonstrated by Uhlir [2]. More recently, it was shown that stain films produced by etching Si in solutions of NaNO 2 in HF and CrO 3 in HF were similar in structure to porous Si films produced by anodic etching [3]. In fact, in the etching of Si by HF:HNO 3 :H 3 O solutions, the oxidation reaction chemistry is recognized to be the same as that of anodic oxidation, with points on the Si surface behaving randomly as localized anodes and cathodes [4]
A microfluidic system integrated with shape memory alloy valves for a safe direct current delivery system

Direct current (DC) has potential as a clinical and scientific tool to accelerate wound healing, increase the permeability of the skin to drug treatment and modulate neural activity. But long duration delivery of DC unavoidably causes hazardous electrolysis at the tissue-electrode interface. To be able to deliver long duration DC, we previously proposed a design for a safe direct current stimulator (SDCS). This device uses alternating current that does not cause chemical reactions at the metal electrodes within the device, but delivers ionic direct current output to the tissue via microfluidic valves. We previously developed and published designs of multiple SDCS components including microfluidic, electronic, data processing, and energy systems. In this paper we focus on the development of the integrated microfluidics needed by the SDCS system. We developed a fabrication method and characterized valve performance within the multi-valve microfluidic system. We used poly-dimethylsiloxane (PDMS) to fabricate three microfluidic chips that integrated valves actuated by 50-µm Nitinol (NiTi) shape memory alloy (SMA) wire. We tested system operation by driving SMA valves with a current pulse and recording the valve response with an electrical assay. The valve operation complied with the SDCS system requirements. The time for valves to open was rapid at 0.177 ± 0.04 seconds, and the time for the valves to close was 0.265 ± 0.05 seconds. Open microfluidic channel impedance for unrestricted ionic current flow was 15.90 ± 8.28 kΩ and it increased by a factor of 40 to restrict ionic current flow at 678 ± 102 kΩ for the closed valves.
A note on the orderability of Dehn fillings of the manifold v2503

We show that Dehn filling on the manifold v2503 results in a non-orderable space for all rational slopes in the interval (−∞,−1). This is consistent with the L-space conjecture, which predicts that...
Don’t Call Us, We’ll Call You: An Empirical Study of Caller Behavior Under a Callback Option

Although call centers have recently invested in callback technology, the effects of this innovation on call center performance are not clearly understood. In this paper, we take a data-driven appro...
Optimal Measurement Configuration In Computational Diffractive Imaging

Diffractive lenses have recently been applied to the domain of multispectral imaging in the X-ray and UV regimes where they can achieve very high resolution as compared to reflective and refractive optics. Conventionally, spectral components are reconstructed by taking measurements at the focal planes. However, the reconstruction quality can be improved by optimizing the measurement configuration. In this work, we adapt a sequential backward selection algorithm to search for a configuration which minimizes expected reconstruction error. By approximating the forward system as a circular convolution and making assumptions on the source and noise, we greatly reduce the complexity of the algorithm. Numerical results show that the configuration found by the algorithm significantly improves the reconstruction performance compared to a standard configuration.
Region Adaptive Graph Fourier Transform for 3D Point Clouds

We introduce the Region Adaptive Graph Fourier Transform (RAGFT) for compression of 3D point cloud attributes. The RA-GFT is a multiresolution transform, formed by combining spatially localized block transforms. We assume the points are organized by a family of nested partitions represented by a rooted tree. At each resolution level, attributes are processed in clusters using block transforms. Each block transform produces a single approximation (DC) coefficient, and various detail (AC) coefficients. The DC coefficients are promoted up the tree to the next (lower resolution) level, where the process can be repeated until reaching the root. Since clusters may have a different numbers of points, each block transform must incorporate the relative importance of each coefficient. For this, we introduce the Q-normalized graph Laplacian, and propose using its eigenvectors as the block transform. The RA-GFT achieves better complexity-performance trade-offs than previous approaches. In particular, it outperforms the Region Adaptive Haar Transform (RAHT) by up to 2.5 dB, with a small complexity overhead.
Ground subspaces of topological phases of matter as error correcting codes

Abstract Topological quantum computing is believed to be inherently fault-tolerant. One mathematical justification would be to prove that ground subspaces or ground state manifolds of topological phases of matter behave as error correction codes with macroscopic distance. While this is widely assumed and used as a definition of topological phases of matter in the physics literature, besides the doubled abelian anyon models in Kitaev’s seminal paper, no non-abelian models are proven to be so mathematically until recently. Cui et al. extended the theorem from doubled abelian anyon models to all Kitaev models based on any finite group (Cui et al., 0000). Those proofs are very explicit using detailed knowledge of the Hamiltonians, so it seems to be hard to further extend the proof to cover other models such as the Levin-Wen. We pursue a totally different approach based on topological quantum field theories (TQFTs), and prove that a lattice implementation of the disk axiom and annulus axiom in TQFTs as essentially the equivalence of TQO1 and TQO2 conditions in Bravyi et al. (2010) and Bravyi et al. (2011). We confirm the error correcting properties of ground subspaces for topological lattice Hamiltonian schemas of the Levin-Wen model and Dijkgraaf-Witten TQFTs by providing a lattice version of the disk axiom and annulus of the underlying TQFTs. The error correcting property of ground subspaces is also shared by gapped fracton models such as the Haah codes (Haah and Jeongwan, 2011; Haah, 2013). We propose to characterize topological phases of matter via error correcting properties, and refer to gapped fracton models as lax-topological.
Electrically driven acousto-optics and broadband non-reciprocity in silicon photonics

Emerging technologies based on tailorable photon–phonon interactions promise new capabilities ranging from high-fidelity information processing to non-reciprocal optics and quantum state control. However, many existing realizations of such light–sound couplings involve unconventional materials and fabrication schemes challenging to co-implement with scalable integrated photonic circuitry. Here, we demonstrate direct acousto-optic modulation within silicon waveguides using electrically driven surface acoustic waves (SAWs). By co-integrating electromechanical SAW transducers with a standard silicon-on-insulator photonic platform, we harness silicon’s strong elasto-optic effect to create travelling-wave phase and single-sideband amplitude modulators from 1 to 5 GHz, with index modulation strengths comparable to electro-optic technologies. Extending this non-local interaction to centimetre scales, we demonstrate non-reciprocal modulation with operation bandwidths of >100 GHz and insertion losses of 100 GHz and insertion losses of <0.6 dB are obtained.
On Volumes of Arithmetic Line Bundles

This paper uses convex bodies to study line bundles in the setting of Arakelov theory. The treatment is parallel to [Yu2], but the content is independent. The method of constructing a convex body in Euclidean space, now called “Okounkov body”, from a given algebraic linear series was due to Okounkov [Ok1, Ok2], and was explored systematically by Kaveh–Khovanskii [KK] and Lazarsfeld–Mustaţǎ [LM]. Many important results of algebraic geometry can be derived from convex geometry through the bridge that the volume of the convex body gives the volume of the linear series. Let K be a number field, X be an arithmetic variety of relative dimension d over OK , and L be a hermitian line bundle over X . There are two important arithmetic invariants ĥ(L) and χ(L). Their growth under tensor powers are measured respectively by vol(L) and volχ(L). In [Yu2], we have introduced the Okounkov body ∆(L) ⊂ R of L, whose volume computes vol(L). It is a natural arithmetic analogue of the construction in [LM]. In the current paper, we use the usual Okounkov body ∆(LK) ⊂ R of the generic fibre LK viewed as a line bundle on the projective variety XK . Then we introduce the Chebyshev ∗The author is fully supported by a research fellowship of the Clay Mathematics Institute.
Cascades and Dissipative Anomalies in Compressible Fluid Turbulence

Turbulence is a highly debated topic and often thought to be unsolvable, especially for compressible fluids. A new analysis shows that work by Lars Onsager in the 1940s is applicable to this problem, shedding light on the physics of dissipative anomalies in a compressible fluid. (Image credit: NASA and ESA; Acknowledgment: J. Hester (ASU) and M. Weisskopf (NASA/MSFC))
Non-commutative instantons and the Seiberg-Witten map

We present several results concerning non-commutative instantons and the Seiberg-Witten map. Using a simple ansatz we find a large new class of instanton solutions in arbitrary even dimensional non-commutative Yang-Mills theory. These include the two dimensional ``shift operator'' solutions and the four dimensional Nekrasov-Schwarz instantons as special cases. We also study how the Seiberg-Witten map acts on these instanton solutions. The infinitesimal Seiberg-Witten map is shown to take a very simple form in operator language, and this result is used to give a commutative description of non-commutative instantons. The instanton is found to be singular in commutative variables.
Graph hypersurfaces and a dichotomy in the Grothendieck ring

The subring of the Grothendieck ring of varieties generated by the graph hypersurfaces of quantum field theory maps to the monoid ring of stable birational equivalence classes of varieties. We show that the image of this map is the copy of Z generated by the class of a point. This clarifies the extent to which the graph hypersurfaces ‘generate the Grothendieck ring of varieties’: while it is known that graph hypersurfaces generate the Grothendieck ring over a localization of Z[L] in which L becomes invertible, the span of the graph hypersurfaces in the Grothendieck ring itself is nearly killed by setting the Lefschetz motive L to zero. In particular, this shows that the graph hypersurfaces do not generate the Grothendieck ring prior to localization. The same result yields some information on the mixed Hodge structures of graph hypersurfaces, in the form of a constraint on the terms in their Deligne–Hodge polynomials. These observations are certainly not surprising for the expert reader, but are somewhat hidden in the literature. The treatment in this note is straightforward and self-contained.
Generic uniqueness of least area planes in hyperbolic space

In this paper, we are interested in the number of solutions to the asymptotic Plateau problem. The asymptotic Plateau problem was solved by Michael Anderson in his seminal paper [1]. Furthermore in [2] he used geometric measure theory methods to prove that for any Jordan curve in S 1.H /, there exists an embedded least area plane in H spanning that curve. Then, Hardt and Lin studied the asymptotic regularity of the least area surfaces in hyperbolic space in [6; 14]. Also, Gabai [5] solved the asymptotic Plateau problem by using topological arguments developed by Hass and Scott [7]. Lang [9] generalized Anderson’s methods to solve the problem in Hadamard Gromov hyperbolic spaces. In [3], the author solved the problem for Gromov hyperbolic spaces with cocompact metric by generalizing Gabai’s techniques.
Extremal Khovanov homology of Turaev genus one links

The Turaev genus of a link can be thought of as a way of measuring how non-alternating a link is. A link is Turaev genus zero if and only if it is alternating, and in this viewpoint, links with large Turaev genus are very non-alternating. In this paper, we study Turaev genus one links, a class of links which includes almost alternating links. We prove that the Khovanov homology of a Turaev genus one link is isomorphic to $\mathbb{Z}$ in at least one of its extremal quantum gradings. As an application, we compute or nearly compute the maximal Thurston Bennequin number of a Turaev genus one link.
Correlation functions in matrix models modified by wormhole terms

We calculate correlation functions in matrix models modified by trace-squared terms. First we study scaling operators in modified one-matrix models and find that their correlation functions satisfy modified Virasoro constraints. Then we turn to dressed order parameters in minimal models and show that their correlators satisfy Goulian-Li formulae continued to negative Liouville dressing exponents. Our calculations provide additional support for the idea that the modified matrix models contain operators with the negative branch of gravitational dressing.