cssi/SciSciGPT-SciSciNet huggingface dataset:
Reply to Csifcsák and Mittner: Fitting data to neural models of mind-wandering.

We recently provided evidence for a nonunitary account of default mode network (DMN) function, because DMN activity was associated with greater mind-wandering (MW) on the one hand, but with behavioral stability on the other (1). Csifcsak and Mittner (2) suggest that their nonunitary model of MW could explain these results. The model predicts distinct neural correlates for attentional states characterized as “off-focus” (a subconscious, exploratory state) versus “active MW” (a focus on an internal train of thought) (3). They offer thought-provoking consequences for interpreting activity that we reported in the frontoparietal network (FPN; no relationship with MW) and medial temporal lobe (MTL) subsystem of … [↵][1]1To whom correspondence should be addressed. Email: eve_valera{at}hms.harvard.edu. [1]: #xref-corresp-1-1
Does this treatment work for me? The patient’s role in assessing medical care

Randomised clinical trials are designed to determine whether a particular treatment is appropriate to make a significant difference to the health of a defined population and to aid its approval for use. For an accurate, cheap and simple assessment to see if a treatment benefits an individual person, all that is needed is a pen, paper, simple pocket calculator and daily recording of a few variables. It requires the ability to read and write and to understand addition and division. Factorial design of experiments is used to show the impact of several variables and their interaction on the person’s health status. An example of a 75-year-old man with an enlarged prostate is used here to illustrate this approach. This person was able to understand and reduce side effects, lower the costs of medication by 83% and improve measured health status by 28%. A multivariate model for this person was then created with about 450 person-days of data.
Can Radiologists Learn From Airport Baggage Screening?: A Survey About Using Fictional Patients for Quality Assurance

Rationale and Objectives For both airport baggage screeners and radiologists, low target prevalence is associated with low detection rate, a phenomenon known as “prevalence effect.” In airport baggage screening, the target prevalence is artificially increased with fictional weapons that are digitally superimposed on real baggage. This strategy improves the detection rate of real weapons and also allows airport supervisors to monitor screener performance. A similar strategy using fictional patients could be applied in radiology. The purpose of this study was twofold: (1) to review the psychophysics literature regarding low target prevalence and (2) to survey radiologists' attitudes toward using fictional patients as a quality assurance tool. Materials and Methods We reviewed the psychophysics literature on low target prevalence and airport x-ray baggage screeners. An online survey was e-mailed to all members of the Association of University Radiologists to determine their attitudes toward using fictional patients in radiology. Results Of the 1503 Association of University Radiologists member recipients, there were 153 respondents (10% response rate). When asked whether the use of fictional patients was a good idea, the responses were as follows: disagree (44%), neutral (25%), and agree (31%). The most frequent concern was the time taken away from doing clinical work (89% of the respondents). Conclusions The psychophysics literature supports the use of fictional targets to mitigate the prevalence effect. However, the use of fictional patients is not a popular idea among academic radiologists.
ESR Resolves the C Terminus Structure of the Ligand-free Human Glutathione S-Transferase A1-1

Nitroxide- and Cu2+-based electron spin resonance (ESR) are combined to provide insight into the conformational states of the functionally important α-helix of the human glutathione S-transferase A1. Distance measurements on various spin-labeled dimeric human glutathione S-transferase A1-1 all result in bimodal distance distributions, indicating that the C-terminus exists in two distinct conformations in solution, one of which closely matches that found in the crystal structure of the ligand-bound enzyme. These measurements permit the generation of a model of the unliganded conformation. Room temperature ESR indicates that the second conformation has high mobility, potentially enabling the enzyme's high degree of substrate promiscuity. This model is then validated using computational modeling and further Cu2+-based ESR distance measurements. Cu2+-based ESR also provides evidence that the secondary structure of the second conformation is of helical nature. Addition of S-hexyl glutathione results in a shift in relative populations, favoring the state that is similar to the previously known structure of the ligand-bound enzyme.
A zero-net-mass-flux actuator for unmanned underwater vehicles

Abstract A set of water tunnel experiments were conducted to establish the viability of a zero-net-mass-flux actuator as a maneuvering mechanism for unmanned underwater vehicles. The actuator, which consisted of a solenoid driving a piston in a cylindrical cavity, was enclosed in a streamlined model vehicle. The forces and moments on the model vehicle were measured by a six-axis load cell connected to the model through a sting. The actuator whose orifice axis was oriented perpendicular to the freestream was located near the aft end of the model. The time averaged thrust was measured for actuator frequencies up to 24 Hz and freestream velocities up to 8 m/s. In absence of freestream flow, scaling arguments indicate that the average thrust increases linearly with the actuator frequency, expelled mass and a characteristic expulsion velocity. The linear frequency dependence was verified experimentally up to a limit imposed by the solenoid response time. Thrust decreased linearly with increasing freestream velocity for values up to the characteristic velocity of actuator. An expression was developed for the time averaged thrust as a function of the actuator design, operating parameters, and freestream velocity.
Medical students and rights campaigns.

Should hospitals allow medical students, physicians, and staff to wear buttons about political issues on their uniforms?
Regulation of Acetylcholine Synthesis in Cholinergic Nerve Terminals

Publisher Summary This chapter discusses the regulation of acetylcholine synthesis in cholinergic nerve terminals. Because the high affinity choline (Ch) transport appears to be obligatory for ACh synthesis, it is necessary to consider the energetics of sodium dependent high affinity choline uptake (SDHACU) prior to examining its coupling to ACh synthesis. Studies with a wide variety of metabolic inhibitors in both synaptosomal and neuromuscular preparations indicate that SDHACU is partially dependent on ongoing metabolism. Inhibition of energy metabolism brought a reduction of Ch uptake in 10 min or less, with respiratory inhibitors and uncouplers of oxidative phosphorylation generally being most effective. Comparison of the effect of inhibiting energy metabolism with the effect of inhibiting Na, K-ATPase on SDHACU suggests that the apparently active nature of Ch transport is mostly, perhaps completely, due to its dependence on continued active pumping of Na + and K + . Inhibition of Na, K-ATPase causes a loss of asymmetric ion distribution, notably the Na + gradient, and a reduction in membrane potential. Indirect evidence suggests that the electrogenic aspects of the Na’ pump makes a contribution to SDHACU.
Representation of Lie Groups and Lie Algebras

The representation of Lie groups is closely related to the representation of their Lie algebras, and we shall discuss them later in this chapter. In the case of compact groups, however, there is a well developed representation theory, which we shall consider in the first section. Before discussing compact groups, let us state a definition and a proposition that hold for all Lie groups.
Why Universal Accessibility Should Matter to the Digital Medievalist

Digital media offer great possibilities for access by the disabled. To ensure access, however, designers must take reasonable measures to ensure that their digital texts conform to relevant accessibility standards. Observing such standards benefits all users and may be a legal requirement. Fortunately, they for the most part are not difficult to implement. This article examines some methods for ensuring accessibility. It also advocates the development of disciplinary standards for accessibility in the design of medieval digital projects. A final section shows the same hypothetical text in accessible and inaccessible codings.
Sub-Nanosecond Gas Breakdown Phenomena in the Voltage Regime Below 15 KV

Fast gaseous breakdown is of interest for both UWB/short pulse electromagnetics, and for plasma limiters to protect devices from high power microwave radiation. A quantitative investigation of fast breakdown phenomena, especially for relatively low voltages and for special geometries, does not exist to the authors’ knowledge. Breakdown in gases is studied in a point-plane geometry with fast high voltage pulsers, covering the parameter range of voltage amplitude 1.7 to 7.5 kV, risetime 400 ps to 1 ns, and pulse duration 1 to 20 ns. The setup consists of a pulser, 50-Ω transmission line, axial needle-plane gap with outer conductor, and 50-Ω load line. The needle consists of tungsten and has a radius of curvature below 0.5 μm. The constant system impedance of 50-Ω (except in the vicinity of the gap) and special transmission-line-type current sensors enables sub-nanosecond current and voltage measurements with a dynamic range covering several orders of magnitude. Digitizing oscilloscopes with sampling rates of 5 ps and 50 ps are used, with analog risetimes of 80 and 240 ps. In addition, the luminosity is measured with a sensitivity of about 10 8 V/W and a risetime of 800 ps. For pulse amplitudes of 1.7 kV (which are doubled at the open gap before breakdown), long pulse duration, and a gap distance of 1 mm, delay times between start of the pulse and start of a measurable current flow (amplitude > several milliamperes) have a minimum of about 8 ns. The pressure dependence of this delay time was measured, in 10 to 600 torr argon, and a minimum is observed at 50 torr Voltages of 7.5 kV produce breakdowns with a delay of about 1 ns. Statistical delays could not be found for either pulse amplitude, with the tip positively pulsed. With negative pulses applied to the tip, at an amplitude of 7.5 kV, breakdown is always observed during the rising part of the pulse, with breakdown delay times below 800 ps. This delay time does not depend on the pressure, and points to a vacuum type discharge with field-emitted electrons as the dominant discharge mechanism for this case.
The Equation \({\rm{\ddot x}}\left( {\rm{t}} \right) + {\rm{f}}\left( {{\rm{x}}\left( {\rm{t}} \right){\rm{\dot x}}\left( {\rm{t}} \right)} \right) + {\rm{g}}\left( {{\rm{x}}\left( {{\rm{t}} - {\rm{r}}} \right)} \right) = 0\)

Consider the equation $${\rm{\ddot x}}\left( {\rm{t}} \right) + {\rm{f}}\left( {{\rm{x}}\left( {\rm{t}} \right){\rm{\dot x}}\left( {\rm{t}} \right)} \right) + {\rm{g}}\left( {{\rm{x}}\left( {{\rm{t}} - {\rm{r}}} \right)} \right) = 0$$ (31.1) where r > 0, f(x) is continuous, g(x) has continuous first derivatives, (a) \({\rm{F}}\left( {\rm{x}} \right) = \int_0^{\rm{x}} {{\rm{f}}\left( {\rm{s}} \right){\rm{ds}}} \) is odd in x. (b) \({\text{F}}\left( {\text{x}} \right) \to \infty {\text{as}}\left| {\text{x}} \right| \to \infty\) and there is a s >0 such that F(x) >0 and is monotone increasing for x > s. (c) g’(x) > 0, xg(x) >0, x ≠ 0, g(x) = -g(-x), g’ (0) = 1. (d) F-1(x) g(F-1 x) )/x→0 as x → ∞.
Abstract cost models for distributed data-intensive computations

We consider data analytics workloads on distributed architectures, in particular clusters of commodity machines. To find a job partitioning that minimizes running time, a cost model, which we more accurately refer to as makespan model, is needed. In attempting to find the simplest possible, but sufficiently accurate, such model, we explore piecewise linear functions of input, output, and computational complexity. They are abstract in the sense that they capture fundamental algorithm properties, but do not require explicit modeling of system and implementation details such as the number of disk accesses. We show how the simplified functional structure can be exploited to reduce optimization cost. In the general case, we identify a lower bound that can be used for search-space pruning. For applications with homogeneous tasks, we further demonstrate how to directly integrate the model into the makespan optimization process, reducing search-space dimensionality and thus complexity by orders of magnitude. Experimental results provide evidence of good prediction quality and successful makespan optimization across a variety of operators and cluster architectures.
Growing into pedagogical partnerships over time and across disciplines: My experience as a non-STEM student consultant in STEM courses

This essay considers the trajectory of my personal and professional growth in my position as a student consultant for three different STEM professors. I explore the unique perspective I brought to this work as a student of the social sciences and I argue for the value of cross-disciplinary pedagogical partnerships.
Size, composition, morphology, and health implications of airborne incidental metal-containing nanoparticles.

There is great concern regarding the adverse health implications of engineered nanoparticles. However, there are many circumstances where the production of incidental nanoparticles, i.e., nanoparti...
Abstract A205: Effects of anti-CTLA-4 and anti-PD-1 on memory T-cell differentiation and resistance to tumor relapse

Both anti-CTLA-4 and anti-PD-1 mediate significant response rates in cancer patients. As a hallmark of successful immunotherapies, they also mediate durable responses that last for years. For example, anti-CTLA-4 mediates a 22% 10-year overall survival rate, while anti-PD-1 mediates a 34% 5-year overall survival rate. Because of the broader uses of immunotherapies, the number of patients who have tumor relapse also increases. About 25% of patients who initially responded to anti-PD-1 have tumor relapse within 24 months. However, the relationship between tumor relapse and long-term effect of immunotherapies is still not clear. The goal of this study is to understand the differential effect of anti-CTLA-4 and anti-PD-1 on memory T-cell differentiation in murine tumor models. By rechallenging mice with tumor cells that have had tumors previously eradicated by either treatment, our results have shown that anti-CTLA-4 induces a more durable memory antitumor response compared to that treated with anti-PD-1. By tracing the antigen-specific CD8 T-cells throughout the memory phase, anti-CTLA-4 increases the frequency and cytokine production of antigen-specific T-cells compared with anti-PD-1. We have also found that anti-CTLA-4 induces the population of KLRG1+ effector CD8 T-cells among the effectors compared with anti-PD-1 during rechallenge, despite the ratio between central memory and effectors remaining the same. Our studies enable us to identify the long-term effect of immunotherapies on immune system. Citation Format: Stephen Mok, Colm R. Duffy, Nana-Ama A.S. Anang, James P. Allison. Effects of anti-CTLA-4 and anti-PD-1 on memory T-cell differentiation and resistance to tumor relapse [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A205.
Input and Output

Information going from the user to the computer is called input, and information from the computer to the user is output. We have used the default form of input/output (often abbreviated as I/O) in Scheme. Input is a product of the interpreter reading in our requests at the > prompt. Output is the results of evaluating our input Scheme expressions that the interpreter prints out.
Level of nutrition and visceral organ protein synthetic capacity and nucleic acid content in sheep.

Thirty-two crossbred wether lambs were assigned to a feed intake level of either ad libitum (ADLIB) for maximum rate of growth or restricted to maintain body weight (MAINT) throughout a 21-d period. At 7-d intervals (d 0.7, 14, and 21), four lambs per treatment were slaughtered to obtain measurements of visceral organ protein synthetic capacity and tissue composition. Protein synthetic capacity was assessed by in vitro [14C]valine incorporation and tissue RNA, DNA, and protein contents. Concentrations of protein and RNA were not significantly affected in most tissues measured. However, for liver, duodenal, and jejunal tissue, DNA concentrations in ADLIB lambs were lower (P less than .05) than in MAINT lambs. Ratios of protein:DNA in most organs were higher (P less than .05) in ADLIB than in MAINT lambs. During the 21-d period, liver and small intestinal protein and RNA mass were higher (P less than .10) in ADLIB than in MAINT lambs, and DNA mass was unaffected. Also during the 21-d period, the average total mass of ruminal protein, RNA, and DNA in ADLIB lambs was higher (P less than .05) than in MAINT lambs. Estimates of valine incorporation and ratios of RNA:protein seemed to reflect protein synthetic capacity of the visceral tissues measured; however, the effect of level of feed intake on these measurements was equivocal. These data suggest that the level of feed intake affected visceral organ mass through changes in cellular hypertrophy.
A phase II study of reduced intensity double umbilical cord blood transplantation using fludarabine, melphalan, and low dose total body irradiation.

In this multicenter Phase 2 single arm study, we substituted low dose total body irradiation (TBI) for antithymocyte globulin (ATG) in a reduced intensity conditioning regimen with the intent to lower the risk for viral infections after double umbilical cord blood (UCB) transplantation. The conditioning regimen consisted of fludarabine (30 mg/m2/day, Day −7 to −2), melphalan (100 mg/m2/day, Day −1), and TBI (200cGy, Day 0). Graft-versus-host disease prophylaxis was sirolimus and tacrolimus. Thirty-one patients were treated on the protocol. The median time of follow-up for survivors was 24 months (range, 3.3–55.1). Nineteen patients experienced a total of 24 clinically significant viral reactivations or infections, with 1-year cumulative incidence rate of first significant viral event as 64% (95% CI, 43–79%), compared with our historical control of 53%. Within the context of these 24 clinically significant viral reactivations, there were a total of 10 infections with organ involvement. Nonrelapse mortality was 28% (95% CI 13–45%) at 2 years. The 2-year overall and progression-free survivals were 53% (95% CI 33–69%) and 47% (95% CI 28–64%), respectively. In conclusion, the substitution of low dose TBI for ATG did not decrease the incidence of significant viral events after UCB transplantation.
PET Myocardial Perfusion Imaging of Extremely Obese Patients: A Study with an Ultra-Large Anthropomorphic Cardiac-Torso Phantom

An increasing number of extremely obese patients (BMI > 40 kg/m2) undergo PET myocardial perfusion imaging (MPI), posing great demands for accurate activity quantitation. An ultra-large anthropomorphic cardiac-torso phantom was custom built to study this case. The phantom was loaded with F-18 with organ concentrations modeling a Rb-82 MPI study. Transmural and 50% transmural defects were placed in the cardiac insert. The phantom was imaged on a TOF PET/CT scanner using clinical acquisition and image reconstruction protocols. Some truncation and streak artifacts were observed on the x-ray CT scan used for attenuation and scatter correction. Myocardial activity appeared relatively uniform and the defects were easily seen in short axis heart slices. Cardiac segments not containing defects showed good uniformity and had normalized perfusion values > 85% of the peak segmental value. An ultra-large anthropomorphic torso phantom is valuable to model Rb-82 myocardial perfusion studies of extremely obese patients.
Cyclin-Dependent Kinases 8 and 19 Regulate Host Cell Metabolism During Dengue Virus Serotype 2 Infection

Dengue virus infection is associated with the upregulation of metabolic pathways within infected cells. This effect is common to infection by a broad array of viruses. These metabolic changes, including increased glucose metabolism, oxidative phosphorylation and autophagy, support the demands of viral genome replication and infectious particle formation. The mechanisms by which these changes occur are known to be, in part, directed by viral nonstructural proteins that contact and control cellular structures and metabolic enzymes. We investigated the roles of host proteins with overarching control of metabolic processes, the transcriptional regulators, cyclin-dependent kinase 8 (CDK8) and its paralog, CDK19, as mediators of virally induced metabolic changes. Here, we show that expression of CDK8, but not CDK19, is increased during dengue virus infection in Huh7 human hepatocellular carcinoma cells, although both are required for efficient viral replication. Chemical inhibition of CDK8 and CDK19 with Senexin A during infection blocks virus-induced expression of select metabolic and autophagic genes, hexokinase 2 (HK2) and microtubule-associated protein 1 light chain 3 (LC3), and reduces viral genome replication and infectious particle production. The results further define the dependence of virus replication on increased metabolic capacity in target cells and identify CDK8 and CDK19 as master regulators of key metabolic genes. The common inhibition of CDK8 and CDK19 offers a host-directed therapeutic intervention that is unlikely to be overcome by viral evolution.
Overview of HPC and AI Computing for COVID-19 in the US

In this talk I'll describe some of the ongoing work in the US applying HPC and AI to COVID-19 related research. I will discuss two activities launched in the spring of 2020, the first is the COVID-19 HPC consortium that joins US supercomputing centers, computing and technology vendors and federal agencies to provide HPC cycles to the SARS-CoV-2/COVID-19 research community and to streamline access to resources via a single proposal mechanism. Currently the HPC consortium has 40 members, access to over 136K nodes, 5M CPUS and 50K GPUs totaling more than 558 Petaflops and is supporting 66 peer reviewed research projects related to the pandemic. The second topic I'll discuss is the nine DOE laboratory collaboration (Argonne, Berkeley, Brookhaven, Oak Ridge, Livermore, Los Alamos, Pacific Northwest, Sandia and SLAC) formed to apply advanced computing to the problem of developing molecular therapeutics for COVID-19. This project is one of part of the DOE sponsored National Virtual BioTechnology Laboratory (NVBTL) formed to coordinate national laboratory efforts related to the pandemic. For each of these I'll give a brief overview of the science, the state of play and how HPC and AI are being used and progress towards solutions.
The scales and signatures of climate adaptation by the Arabidopsis transcriptome

Clines in allele frequency and trait variation can be highly informative for understanding how populations have historically adapted to climate variation across landscapes. However, as a consequence of the many complexities inherent to this process, these climate-associated differentiation patterns can be confounded, misleading, or obscured. Molecular phenotypes like gene expression levels are a potentially valuable means for resolving these complexities. Their intermediate position between genomes and organismal traits and their interrelatedness structured by gene regulatory networks can help parse how different climatic factors contribute to unique components of range-wide or region-specific diversity patterns. Here, we demonstrate these explanatory values of gene expression variation through integrative analyses of transcriptomic data from 665 Arabidopsis thaliana accessions. Differentiation of co-expressed genes is often associated with source site climate. Although some patterns hold range-wide, many other gene expression clines are specific to particular ancestry groups, reflecting how broad-scale and local combinations of selective agents differentially resolve functional interrelationships between plant defense, drought tolerance, and life history traits. We also extend these analyses to parse how different factors explain climate-associated variation in flowering time and its plasticity. Expression of key regulators FLC and SOC1 strongly predicts time to flower, consistent with previous work, but our results also highlight novel relationships that indicate as yet unexplored climate-related connections between defense signaling and flowering. Finally, we show that integrative models combining genotype and gene expression information predict variation in flowering time under ecologically realistic conditions more accurately than models based on either source alone.
Ultra-low threshold polariton condensation

We demonstrate the condensation of microcavity polaritons with a very sharp threshold occurring at a two orders of magnitude pump intensity lower than previous demonstrations of condensation. The long cavity lifetime and trapping and pumping geometries are crucial to the realization of this low threshold. Polariton condensation, or "polariton lasing" has long been proposed as a promising source of coherent light at a lower threshold than traditional lasing, and these results indicate some considerations for optimizing designs for lower thresholds.
Quantification of CEA from Human Plasma using Plasmonic Enhancement of Fluorescence and Acoustic Streaming

Carcinoembryonic antigen (CEA) is a prognostic biomarker for colon cancer and is elevated in many other cancers such as ovarian cancer and pancreatic cancers. We introduce an optimized technique based on plasmonic enhancement of fluorescence to lower the detection limit of CEA to sub ng/ml levels. Nanostructures generated using rapid thermal annealing of thin silver films, covered by a silica layer, enhanced fluorescence intensity to lower the detection limit to about 100 pg/ml and increase sensitivity by a factor of 18. Additionally, acoustic streaming generated by Rayleigh surface acoustic waves (SAWs) was utilized to address interference from non-specifically bound (NSB) proteins in the quantification of CEA from human plasma. It is shown that NSB proteins in human plasma can be successfully reduced using acoustic streaming to achieve a CEA detection limit of 500pg/mL in plasma.
The structure and perceptual basis of social judgments from faces

Abstract Two questions have motivated much of our research. What is the structure of social judgments from faces and what is the perceptual basis of these judgments? Twelve years ago, we proposed a simple 2-dimensional model, according to which faces are evaluated on perceived valence and power, and introduced data-driven computational models, which reveal the physical variation of faces that drive specific judgments. First, using data from our lab collected more than 10 years later and from a large cross-cultural replication project, we show that the simplistic 2D structure model is remarkably stable and generalizes to all world regions, in which data have been collected. We also discuss misunderstandings and limitations of structure models. Second, we make the assumptions of the data-driven modeling approach transparent and discuss recent developments. The computational framework allows for precise parametric manipulation of the appearance of faces, for control of shared variance between judgments, and for relating models at different levels of face processing. We also explore analyses mapping multiple social judgments simultaneously to the physical face space. We conclude with two future directions: models of hyper-realistic faces and the underappreciated role of stable individual differences in judgments.
Radiative Relaxation in Luminescent Silicon Nanocrystal Thiol-Ene Composites

Efficient photoluminescence (PL) from silicon nanocrystal (SiNC) composites has important implications for emerging solar-collection technologies, yet a detailed understanding of the landscape of P...
A highly efficient metal-free protocol for the synthesis of linear polydicyclopentadiene

We have achieved breakthroughs for the efficient synthesis of linear polydicyclopentadiene (pDCPD) via photoredox mediated metal-free ring-opening metathesis polymerization (MF-ROMP). Molecular weight control from 1 to 16 kDa can be targeted in a straightforward manner. Assisted by this method, the Tg–Mn dependence of linear pDCPD is investigated and reported for the first time.
Wanitoon ani Mikan Odenang: Anishinaabe Urban Loss and Reclamation

This article focuses on the loss of identity through cartographic colonization. From an Anishinaabe perspective, many of the most diverse urban centers in the Great Lakes region of North America ar...
Unindicated cervical cancer screening in adolescent females within a large healthcare system in the United States.

Background Current consensus recommendations are to not initiate cervical cancer screening for immunocompetent adolescent females before 21 years of age. This is in part because of the very low rate of 0.8 per 100,000 new cervical cancer cases diagnosed among women aged between 20 to 24 years. Timely human papillomavirus vaccination further decreases the incidence of cervical cancer to 4 cases per 100,000 persons by the age of 28 years. Screening before 21 years of age has demonstrated no clear benefit in cancer risk reduction or outcomes. In addition, unindicated screening among adolescents can lead to patient harm and increasing costs to the healthcare system. Objective It is important to assess the rates of overutilization of cervical cancer screening and to identify areas where improvements have occurred and where further opportunities exist. This study aimed to assess the trends over time and the practice and provider factors associated with unindicated cervical cancer screening tests in adolescent females within the largest healthcare system in the state. Study Design Cross-sectional data from patients aged 13 to 20 years who underwent cervical cancer screening between January 1, 2012, and December 31, 2018, across a large multihospital health system were reviewed. All cervical cancer screening results were included. The incidence rate of unindicated screening was analyzed over 6-month intervals using the Poisson regression analysis. Results The study included data from 118 providers and 794 women. Among the 900 screening results, most (90%) were unindicated: 87% with unindicated cytology testing alone and 14% with unindicated human papillomavirus testing. Screening tests were collected from patients aged 13 to 20 years, many of whom had multiple unindicated cytology tests, with 25 patients having ≥3 tests before the age of 21 years. Most results of cytology testing were negative for intraepithelial lesion or malignancy (77%). Moreover, 52 invasive diagnostic or therapeutic procedures (49 colposcopies and 3 conizations) were performed, of which 45 (87%) followed an unindicated screening test. Between 2012 and 2018, the incidence rate of unindicated cytology decreased by 33% (12.6 to 8.5 unindicated cytology per 1000 encounters). The incidence rate of unindicated screening was lower in the academic setting than in the community setting (incidence rate ratio, 0.43; P Conclusion Despite substantial reductions in unindicated screening for women aged
Stochastic vs. Deterministic Modeling for the Spread of COVID-19 in Small Networks

This paper proposes and analyzes a stochastic Susceptible-Exposed-Infected-Removed (SEIR) spreading model on networks. Imagine a nursing home housing 28 seniors and 7 staff workers, in which one of the staff has tested positive for COVID-19. Unfortunately, the results of this test are 3 days late and the infected person had not been quarantining while waiting for their test results. What is now the individual risk to the different people living in this nursing home? If the home has access to two rapid COVID-19 viral tests, who should they be given to and why? In order to answer questions like this, we need to study stochastic models rather than deterministic ones. Unlike the vast majority of works that analyze various deterministic models, stochastic models are required when analyzing the risk of COVID-19 to individual people rather than tracking aggregate numbers in a given region. More specifically, this paper compares the results provided by analyzing stochastic and deterministic models and investigating when it is suitable to use the different models. In particular, we show why it is not suitable to use deterministic models when analyzing the spread in small communities and how these questions can be better addressed using stochastic ones. Finally, we show the added complications that arise due to the relatively long incubation period of COVID-19, and how it can be addressed. A simulated case study of the spread of COVID-19 in a 35-person nursing home is used to help illustrate our results.
The Moderating Effect of Democracy on Climate-Induced Social Conflict: Evidence from Indian Districts:

Do political institutions moderate the effect of environmental stress on social conflict? We posit that while the frequency of social conflict in developing agrarian states can increase during drou...
Attack by a common parasitoid stabilizes population dynamics of multi-host communities.

Abstract We model the population dynamics of two host species attacked by a common parasitoid using a discrete-time formalism that captures their population densities from year to year. It is well known starting from the seminal work of Nicholson and Bailey that a constant parasitoid attack rate leads to an unstable host-parasitoid interaction. However, a Type III functional response, where the parasitoid attack rate accelerates with increasing host density stabilizes the population dynamics. We first consider a scenario where both host species are attacked by a parasitoid with the same Type III functional response. Our results show that sufficient fast acceleration of the parasitoid attack rate stabilizes the population dynamics of all three species. For two symmetric host species, the extent of acceleration needed to stabilize the three-species equilibrium is exactly the same as that needed for a single host-parasitoid interaction. However, asymmetry can lead to scenarios where the removal of a host species from a stable interaction destabilizes the interaction between the remaining host species and the parasitoid. Next, we consider a situation where one of the host species is attacked at a constant rate (i.e., Type I functional response), and the other species is attacked via a Type III functional response. We identify parameter regimes where a Type III functional response to just one of the host species stabilizes the three species interaction. In summary, our results show that a generalist parasitoid with a Type III functional response to one or many host species can play a key role in stabilizing population dynamics of host-parasitoid communities in apparent competition.
Softmax Tree: An Accurate, Fast Classifier When the Number of Classes Is Large

Classification problems having thousands or more classes naturally occur in NLP, for example language models or document classification. A softmax or one-vs-all classifier naturally handles many classes, but it is very slow at inference time, because every class score must be calculated to find the top class. We propose the “softmax tree”, consisting of a binary tree having sparse hyperplanes at the decision nodes (which make hard, not soft, decisions) and small softmax classifiers at the leaves. This is much faster at inference because the input instance follows a single path to a leaf (whose length is logarithmic on the number of leaves) and the softmax classifier at each leaf operates on a small subset of the classes. Although learning accurate tree-based models has proven difficult in the past, we are able to overcome this by using a variation of a recent algorithm, tree alternating optimization (TAO). Compared to a softmax and other classifiers, the resulting softmax trees are both more accurate in prediction and faster in inference, as shown in NLP problems having from one thousand to one hundred thousand classes.
Annual Review of Comparative and International Education 2013

The goal of the ARCIE volume is to examine current perspectives and future directions for the field using several essays as a context for discussion and analysis.
Principal Component Analysis and Optimization: A Tutorial

Principal component analysis (PCA) is one of the most widely used multivariate tech- niques in statistics. It is commonly used to reduce the dimensionality of data in order to examine its underlying structure and the covariance/correlation structure of a set of variables. While singular value decomposition provides a simple means for identi- cation of the principal components (PCs) for classical PCA, solutions achieved in this manner may not possess certain desirable properties including robustness, smooth- ness, and sparsity. In this paper, we present several optimization problems related to PCA by considering various geometric perspectives. New techniques for PCA can be developed by altering the optimization problems to which principal component loadings are the optimal solutions.
Demonstration of Protective (Inhibitory) Effects of Urinary Macromolecules on the Crystallization of Calcium Oxalate

Several inhibitors of kidney stone salt crystallization have been found to be effective in human urine which has led to the hypothesis that kidney stones may be caused by a deficiency of inhibitors in an otherwise normal supersaturated urine. Several small molecular weight (<1000) inhibitors of calcium oxalate and/or calcium phosphate crystallization have been reported 1 2 3. In a comparison of human urinary retentates with their dialysates, our laboratory has previously found a significant inhibition of the crystallization of urinary calcium oxalate by urinary macromolecules (UMM).4
Value of Radiologic Skeletal Survey in Assessment of Abused Children

The usefulness of the radiologic skeletal survey in the assessment of children who were suspected of being abused on neglected was studied. During a 2½-year period at one pediatric hospital, 331 skeletal surveys were performed to aid in the evaluation of possible child maltreatment. Of the 331 surveys, 38 (11.5%) showed evidence of trauma. But, in 30 of the 38 skeletal surveys, trauma was either previously known or suspected by the examiner. Therefore, in only eight cases did the skeletal survey provide new information that was helpful in the investigation of possible abuse or neglect which would have remained undiscovered without the skeletal survey. The age, sex, and clinical signs of the subjects were analyzed in an attempt to identify factors that might predict skeletal surveys with positive radiologic findings. Consideration is given to the costs and risks of skeletal surveys v potential benefits.
Segmentation and morphology

11 Introduction 41.1 Generalremarks 41.2 Morphology 61.3 Staticanddynamicmetaphors 92 Unsupervisedlearningofwords 112.1 Thetwoproblemsofwordsegmentation 112.2 Trawlingforchunks 142.3 Word Boundary detectors 212.4 Successesandfailuresinwordsegmentation 223 Unsupervisedlearningofmorphology 233.1 Zellig Harris 233.2 Usingdescriptionlength 243.3 Workintheﬁeld 274 Implementingcomputationalmorphologies 294.1 Finitestatetransducers 304.2 Morphophonology 335 Conclusions 35References 36
Carbon Sequestration in Soils

The production, transport, and application of N fertilizer incur COemissions to the atmosphere, which must be subtracted from any apparent increases in soil organic matter before calculating the net carbon sequestration in agricultural soils. Similarly, net carbon sequestration in arid-land soils is reduced by COis emissions when fossil fuels are used to pump irrigation water and when pedogenic carbonate precipitates in soils. Application of manure, important to maintaining agricultural tilth, does not offer a mechanism for the net sequestration of carbon in soils that is relevant to the Kyoto Protocol.
Towards efficient on-demand VM provisioning: Study of VM runtime I/O access patterns to shared image content

IaaS clouds are becoming a standard way of providing elastic compute capacity at an affordable cost. To achieve that, VM provisioning system has to optimally allocate I/O and compute resources. One of the significant optimization opportunities is to leverage content similarity across VM images. While many studies have been devoted to de-duplication of VM images, this paper is to the best of our knowledge, the first one to comprehensively study the relationship between the VM image similarity structure and the runtime I/O access patterns. Our study focuses on block-level similarity and I/O access patterns, revealing correlations between common content of different images and application-level access semantics. Furthermore, it also zooms on several runtime I/O access pattern aspects, such as the similarity of the sequences in which common content is accessed. The results show a strong tendency for access pattern locality within common content clusters across VM images, regardless of the rest of the composition. Furthermore, it reveals a strong tendency for read accesses to refer to the same subsets of blocks within the common content clusters, while preserving the same ordering. These results provide important insights that can be used to optimize on-demand VM image content delivery under concurrency.
Position-dependent instability of ribosomal DNA repeats (736.1)

Repetitive DNA arrays are ubiquitous in eukaryotic genomes and represent a special challenge for genome integrity because of the risk of non-allelic recombination. We used unique sequence tags marking individual repeats in the tandem ribosomal DNA (rDNA) array of budding yeast to determine the likelihood of non-allelic recombination throughout the array. We found that rDNA repeat stability during meiotic recombination is strongly dependent on relative repeat position, with repeats near the rDNA border being more susceptible to meiotic DNA double-strand breaks (DSBs) and thus non-allelic recombination. The DSB position effect is promoted by rDNA heterochromatin and suppressed by the origin recognition complex component Orc1. Border-dependent position effects in the rDNA also occur at the level of reporter gene expression in vegetative cells, suggesting that such effects are a reflection of a general feature of rDNA structure. Our results indicate that, despite their identity at the sequence level, rDNA rep...
Radiocarbon Dating of Interdune Paleo‐Wetland Deposits to Constrain the Age of Mid‐to‐Late Holocene Microlithic Artifacts from the Zhongba site, Southwestern Qinghai‐Tibet Plateau

Microlithic artifacts, some found in situ, are abundant in the Zhongba archaeological site in southwestern Tibet. The site environment consists of extant wetlands and paleo-wetland deposits found in depressions between sand dunes derived from the Yarlung Tsangpo floodplain. Constraining 14C dates from wetland vegetation and shell from one site fall between ca. 6600–2600 cal. yr B.P., while a second site is dated 3400–1200 cal. yr B.P. A significant and variable 14C reservoir effect—up to 1400 14C yr—limits these ranges to terminus post quem constraints. The in situ artifacts are supplemented by surface collections fully characterizing raw material and typological variability for each site. Raw material found at Zhongba is chert and chalcedony likely sourced from Cretaceous bedrock near the site. Typologically, microblades are nongeometric and are derived from conical and wedge-shaped cores similar to those identified in the Qinghai Lake Basin and the Chang Tang Nature Reserve of similar or greater age. The later occupation period at Zhongba is broadly contemporaneous with sites on the Qinghai-Tibet Plateau containing bronze and iron artifacts, indicating microlithic technology remained an important tool-making strategy in western Tibet late into the protohistoric period.
Magnetic fringe-field control of electronic transport in an organic film

Random, spatially uncorrelated nuclear-hyperfine fields in organic materials dramatically affect electronic transport properties such as electrical conductivity, photoconductivity, and electroluminescence. The influence of these nuclear-hyperfine fields can be overwhelmed by a uniform externally applied magnetic field, even at room temperature where the thermodynamic influences of the resulting nuclear and electronic Zeeman splittings are negligible. As a result, even in applied magnetic fields as small as 10 mT, the kinetics of exciton formation, bipolaron formation, and single-carrier hopping are all modified at room temperature, leading to changes in transport properties in excess of 10% in many materials. Here, we demonstrate a new method of controlling the electrical conductivity of an organic film at room temperature, using the spatially varying magnetic fringe fields of a magnetically unsaturated ferromagnet. (The fringe field is the magnetic field emanating from a ferromagnet, associated with magnetic dipole interactions or, equivalently, the divergence of the magnetization within and at the surfaces of the ferromagnet.) The ferromagnet’s fringe fields might act as a substitute for either the applied magnetic field or the inhomogeneous hyperfine field. The size of the effect, the magnetic-field dependence, and hysteretic properties rule out a model where the fringe fields from the ferromagnet provide a local magnetic field that changes the electronic transport properties through the hyperfine field, and show that our effects originate from electrical transport through the inhomogeneous fringe fields coming from the ferromagnet. Surprisingly, these inhomogeneous fringe fields vary over length scales roughly 2 orders of magnitude larger than the hopping length in the organic materials, challenging the fundamental models of magnetoresistance in organic layers which require the correlation length of the inhomogeneous field to correspond roughly to the hopping length.
Technical Communique: Adaptive control for nonlinear nonnegative dynamical systems

Nonnegative and compartmental models are widespread in engineering systems and life sciences and play a key role in the understanding of these systems. In this paper, we develop a direct adaptive control framework for nonlinear uncertain nonnegative and compartmental dynamical systems. The proposed framework is Lyapunov-based and guarantees partial asymptotic set-point regulation; that is, asymptotic set-point regulation with respect to part of the closed-loop system states associated with the plant. In addition, the adaptive controller guarantees that the physical system states remain in the nonnegative orthant of the state space.