cssi/SciSciGPT-SciSciNet huggingface dataset:
Automated soil inference under fuzzy logic

Abstract Soil information is essential to any terrestrial ecological modelling and management activity. Polygon soil maps produced from soil surveys are currently the major source of information on the spatial distribution of soil properties for a variety of land analysis and management activity. However, there are some major problems regarding the use of current soil maps in geographic analysis and especially in geographic information systems (GIS). These problems include limited coverage at a fixed scale, locational errors, attribute errors, and insufficient information in the mapping units. Much of these problems are due to the crisp logic and cartographic techniques with which soil maps are produced. Under crisp logic standardly used in soil classification and mapping, an area belongs to one and only one soil mapping unit, and is separated from other mapping units by sharp boundary lines. However, soil in a landscape is a continuum and the discretization of such a continuum into distinct spatial and categorical groups results in a significant loss of information. This paper presents a methodology to infer and represent information on the spatial distribution of soil. The methodology combines fuzzy logic with GIS and expert system development techniques to infer soil series from environmental conditions. The methodology for every point in an area produces a soil similarity vector (SSV) showing the similarity of the soil at the point to a prescribed set of soil series. The SSV produced from this methodology can be used to infer local soil properties at values intermediate to the typical or central values assigned to each possible series. Preliminary results from the methodology using a limited set of environmental variables for an experimental watershed in Montana are presented.
Retrospective Higher-Order Markov Processes for User Trails

Users form information trails as they checkin with a geolocation, rate items, or consume media. A common problem is to predict what a user might do next for the purposes of guidance, recommendation, or prefetching. Markov chains models have been widely used methods to study such sequences of data. First-order Markov chains are easy to estimate, but lack accuracy when history matters. Higher-order Markov chains, in contrast, have too many parameters and suffer from overfitting the training data. Fitting these parameters with regularization and smoothing only offers mild improvements. In this paper we propose the retrospective higher-order Markov process (RHOMP) as a low-parameter model for such sequences. This model is a special case of a higher-order Markov chain where the transitions depend retrospectively on a single history state instead of an arbitrary combination of history states. There are two immediate computational advantages: the number of parameters is linear in the order of the Markov chain and the model can be fit to large state spaces. Furthermore, by providing a specific structure to the higher-order chain, RHOMPs improve the model accuracy by efficiently utilizing history states without risks of overfitting the data. We demonstrate how to estimate a RHOMP from data and we demonstrate the effectiveness of our method on various real application datasets spanning geolocation data, review sequences, and business locations. The RHOMP model uniformly outperforms higher-order Markov chains, Kneser-Ney regularization, and tensor factorizations in terms of prediction accuracy.
Exploring young consumers’ trust and purchase intention of organic cotton apparel

Purpose: The purpose of this study is to examine the effects of corporate social responsibility (CSR) reputation, product price and organic label on consumers’ perceptions of quality, trust and purchase intentions of organic apparel products by surveying American young consumers. Design/methodology/approach: An intercept survey approach was used to administer a written questionnaire to a sample of college students. The experiment is a 2 (CSR reputation: poor vs good) × 2 (price: low vs high) × 2 (organic label: absent vs present) factorial design. Findings: The results of our study suggest that retailers’ CSR reputation had a significant positive effect on perceived quality, consumer trust and purchase intentions, and price had a negative impact on consumers’ purchase intentions. Results also revealed a significant three-way interaction among the three independent variables on perceived quality and consumer trust.Originality/value: This research is the first empirical effort to investigate the key factors that may influence young consumers’ perceptions of quality, trust and purchase intentions of organic products by considering joint use of CSR reputation, product price and an organic label, which represents a realistic buying condition. Consequently, the findings of this study represent an important step forward in better understanding consumers’ buying behavior toward green products.
Vacuum spin squeezing

We investigate the generation of entanglement (spin squeezing) in an optical-transition atomic clock through the coupling to an optical cavity in its vacuum state. We show that if each atom is prepared in a superposition of the ground state and a long-lived electronic excited state, and viewed as a spin-1/2 system, then the collective vacuum light shift entangles the atoms, resulting in a squeezed distribution of the ensemble collective spin, without any light applied. This scheme reveals that even an electromagnetic vacuum can constitute a useful resource for entanglement and quantum manipulation. By rotating the spin direction while coupling to the vacuum, the scheme can be extended to implement two-axis twisting resulting in stronger squeezing.
A Novel Potential Field Controller for Use on Aerial Robots

Unmanned aerial vehicles, commonly known as drones, have many potential uses in real-world applications. Drones require advanced planning and navigation algorithms to enable them to safely move through and interact with the world around them. This paper presents an extended potential field controller (ePFC) which enables an aerial robot, or drone, to safely track a dynamic target location while simultaneously avoiding any obstacles in its path. The ePFC outperforms a traditional potential field controller with smoother tracking paths and shorter settling times. The proposed ePFC’s stability is evaluated by Lyapunov approach, and its performance is simulated in a MATLAB environment. Finally, the controller is implemented on an experimental platform in a laboratory environment which demonstrates the effectiveness of the controller.
Role of the ocean's AMOC in setting the uptake efficiency of transient tracers

The central role played by the ocean's Atlantic Meridional Overturning Circulation (AMOC) in the uptake and sequestration of transient tracers is studied in a series of experiments with the GISS and MIT ocean circulation models. Forced by observed atmospheric timeseries of CFC-11, both models exhibit realistic distributions in the ocean, with similar surface biases but different response over time. To better understand what controls uptake, we ran idealized forcing experiments in which the AMOC strength varied over a wide range, bracketing the observations. We found that differences in the strength and vertical scale of the AMOC largely accounted for the different rates of CFC-11 uptake and vertical distribution thereof. A 2-box model enables us to quantify, and relate uptake efficiency of passive tracers to AMOC strength and how uptake efficiency decreases in time. We also discuss the relationship between passive tracer and heat uptake efficiency, of which the latter controls the transient climate response to anthropogenic forcing in the North Atlantic. We find that heat uptake efficiency is substantially less (by about a factor of five) than that for a passive tracer.
Tensor-Dictionary Learning with Deep Kruskal-Factor Analysis

A multi-way factor analysis model is introduced for tensor-variate data of any order. Each data item is represented as a (sparse) sum of Kruskal decompositions, a Kruskal-factor analysis (KFA). KFA is nonparametric and can infer both the tensor-rank of each dictionary atom and the number of dictionary atoms. The model is adapted for online learning, which allows dictionary learning on large data sets. After KFA is introduced, the model is extended to a deep convolutional tensor-factor analysis, supervised by a Bayesian SVM. The experiments section demonstrates the improvement of KFA over vectorized approaches (e.g., BPFA), tensor decompositions, and convolutional neural networks (CNN) in multi-way denoising, blind inpainting, and image classification. The improvement in PSNR for the inpainting results over other methods exceeds 1dB in several cases and we achieve state of the art results on Caltech101 image classification.
Spatiotemporal Convergence of Crime and Vehicle Crash Hotspots: Additional Consideration for Policing Places:

Policing strategies that seek to simultaneously combat crime and vehicle crashes operate under the assumption that these two problems have a corollary relationship—an assumption that has received scant empirical attention and is the focus of the present study. Geocoded vehicle crash, violent crime, and property crime totals across were aggregated to Indianapolis census blocks over a 36-month period (2011-2013). Time series negative binomial regression and local indicators of spatial autocorrelation analyses were conducted. Results indicate that both violent and property crime are significantly related to vehicle crash counts, both overall and during the temporal confines of patrol tours. Relationship strength was modest. Spatiotemporal analysis of crime and crash data can identify places for police intervention and improved scholarly evaluation.
Control Challenges From Space and Ground Based Astronomical Telescopes

Abstract Actively controlled optics are revolutionizing the telescope builders art, by enabling the use of active atmospheric compensation, large segmented mirrors, multiple-aperture telescopes, space telescopes and other innovations. Designing high-performance controllers for these instruments requires an accurate means of calculating optical performance: a particular method is presented. A survey of the field and a detailed example illustrate some of the challenges that arise.
BANK FAILURES UNDER MANAGERIAL AND REGULATORY INEFFICIENCY: THREE DECADES OF EVIDENCE FROM TURKEY

Drawing on a comprehensive data set from Turkey (1970â€“2003) and using both nonparametric (data envelopment analysis) and parametric (stochastic frontier analysis) frontier methods, we estimate 16 alternative efficiency measures to study their associations with the probability of bank failures in an emerging market setting. We find that failed banks severely underperform survived banks in all forms of efficiency and that their subpar performance deteriorates closer to failure, prosperous times and bloated scales tend to precede eventual banking fatalities, managerially induced (technical) inefficiencies dominate politically induced (allocative) inefficiencies in failed banks, and banks with new ownership and affiliation with other businesses are more likely to fail. The results also caution that liquidity, capital, and currency risks combined with poor management are a lethal mix ahead of crises.
A Dynamical Systems Approach to Control

Abstract Control systems can be viewed as dynamical systems over (infinite) dimensional state spaces. From this point of view the long term behavior of control systems, such as limit sets, Morse sets, approximations on the entire time axis, ergodicity, Lyapunov exponents, stable find unstable manifolds etc. becomes accessible. This paper presents some of the underlying theory, as well as applications to the global characterization of control systems with bounded control range that are not completely controllable, to control of chaotic systems, and to exponential stability of uncertain systems.
Energy implications of solid-state lighting technology

The efficient yet highly controllable generation of light can be accomplished by light-emitting diodes that can have a 20 times greater efficiency than incandescent light sources. Implications on energy, environment, and finances will be discussed.
Atypical depression and double depression predict new-onset cardiovascular disease in U.S. adults.

BACKGROUND Although depression is a risk factor for cardiovascular disease (CVD), it is unknown whether this risk varies across depressive disorder subtypes. Thus, we investigated atypical major depressive disorder (MDD) and double depression as predictors of new-onset CVD in a nationally representative sample of U.S. adults. METHODS Prospective data from 28,726 adults initially free of CVD who participated in Wave 1 (2001–2002) and Wave 2 (2004–2005) of the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) were examined. Lifetime depressive disorder subtypes (Wave 1) and incident CVD (Wave 2) were determined by structured interviews. RESULTS We identified 1,116 incident CVD cases. In demographics adjusted models, the atypical MDD group had a higher odds of incident CVD than the no depression history (OR = 2.19, 95% CI: 1.71–2.81, P < .001), dysthymic disorder only (OR = 1.61, 95% CI: 1.08–2.39, P = .019), and nonatypical MDD (OR = 1.46, 95% CI: 1.11–1.91, P = .006) groups. Likewise, the double depression group had a higher odds of incident CVD than the no depression history (OR = 2.17, 95% CI: 1.92–2.45, P < .001), dysthymic disorder only (OR = 1.59, 95% CI: 1.16–2.19, P = .004), and MDD only (OR = 1.46, 95% CI: 1.20–1.77, P < .001) groups. Relationships were similar but attenuated after adjustment for CVD risk factors and anxiety disorders. CONCLUSIONS Adults with atypical MDD or double depression may be subgroups of the depressed population at particularly high risk of new-onset CVD. Thus, these subgroups may (a) be driving the overall depression–CVD relationship and (b) be in need of earlier and/or more intense CVD primary prevention efforts to reduce their excess CVD burden.
Acute Interstitial Nephritis Associated With Mezlocillin, Nafcillin, and Gentamicin Treatment for Pseudomonas Infection

• Two patients developed acute interstitial nephritis (AIN) following treatment with mezlocillin sodium. Diagnosis was made by renal biopsy. Gallium 67 citrate scanning was abnormal in both. All patients were receiving multiple-drug therapy, but AIN has either not been described with the other drugs, or the temporal relationship between the AIN and termination of other drug therapy makes a causative relationship unlikely. All were infected withPseudomonas aeruginosa. A role for the infecting organism or drug synergism in contributing to the renal disease cannot be excluded. (Arch Intern Med1985;145:1204-1207)
Testosterone-Secreting Adrenal Adenoma Containing Crystalloids Characteristic of Leydig Cells

A 49-year-old woman with virilization demonstrated biochemical features traditionally ascribed to virilizing ovarian tumors: marked elevation of serum testosterone level with normal urinary excretion of 17-ketosteroids and normal serum dehydroepiandrosterone level. An adrenal cortical adenoma containing neoplastic cells indistinguishable from Leydig cells, including the demonstration of characteristic crystalloids of Reinke, was shown to be the source of the elevated testosterone level. A review of the literature revealed 13 cases with a similar biochemical profile, and of these, two were reported to contain crystalloids of Reinke. Taking cognizance of the fact that these characteristic crystalloids are only found in 40 percent of Leydig cell tumors of the testis, it is concluded that Leydig cells may be present in, and may be active participants in, the pathophysiology of a number of testosterone-secreting adrenal tumors.
Two dimensional arrays for real time 3D intravascular ultrasound.

We have previously described 2D arrays operating at up to 10.0 MHz consisting of several thousand elements for transthoracic cardiac imaging and over a hundred elements for intracardiac imaging using 7 Fr to 12 Fr catheters. We have begun to explore forward viewing real time 3D phased array intravascular ultrasound, which may require imaging depths of a few centimeters to look down the axis of a vessel to view vulnerable atherosclerotic plaque. We used a noncoaxial based cable technology that allowed 100 signal wires to be placed inside a 4.8 French IVUS lumen with an inner diameter of 1.3 mm. We pursued two different fabrication technologies for the building of the transducers. Each transducer was constructed in the forward viewing configuration to allow simultaneous real time B-scans, C-scans and volumetric rendering of vessels and vascular stents distal to the catheter tip. In order to obtain the desired penetration depth, each transducer was constructed to operate at 10.0 MHz. The first method included an ordered array of 11 × 11 = 121 elements. In order to conform to the round aperture of the IVUS lumen, the corners were cut off, resulting in a total of 97 signal channels. Real time images include a 4 mm diameter vessel in a tissue mimicking phantom, an expanded stent and a stent in an excised sheep aorta. The second method is based upon a laser dicing technique that cuts the individual elements in a random pattern. This resulted in 61 signal channels. Real time 3D images of the AIUM test object were made with this transducer.
The Clinical and Urodynamic Effects of Anterior Vaginal Repair and Burch Colposuspension

The clinical and urodynamic effects of anterior vaginal repair and Burch colposuspension for correction of stress urinary incontinence were assessed in a prospective study. Ninety women undergoing surgery for the first time because of genuine stress incontinence were studied. A full clinical examination including simultaneous urethrocystometry according to a standardized methodology with the patients in the supine, sitting, and standing positions was performed preoperatively, 3 months postoperatively, and again 1 to 2 years later. Clinical follow-up continued for 5 to 7 years. Neither surgical anterior vaginal repair nor Burch colposuspension affected the resting variables of the urethral sphincter mechanism. After Burch colposuspensio? the transmitted intraabdominal pressure to the urethra significantly increased in all recording positions in all women who were successful!y treated. After successful anterior colporrhaphy, the increase in pressure transmission from the abdomen to the urethra was less prominent and was only present in the sitting and standing positions. The postural changes in the urethral pressure profile characteristic of stress urinary incontinence were still present even after successful restoration of continence. The impact of successful surgery for stress incontinence is the enhancement of transmission of the intraabdominal pressure rise to the proximal urethra. This is achieved primarily by anatomic alterations rather than by altering urethral sphincter function. Burch colposuspension was more effective for the correction of genuine stress incontinence than was anterior vaginal repair. (AM J OBSTET GYNECOL 1988;159:137-44.)
Biostatistical Trends in Pediatrics: Implications for the Future

All physicians face the challenge of keeping abreast with a body of medical knowledge that is growing at an exponential rate. On this account, physicians often spend countless hours each month reading journals to "keep current" with recently described techniques of diagnosis and therapy. To gain maximal benefit from their reading, physicians must be able to assess the scientific merit of published research. They must evaluate the various claims and conclusions and then decide which are valid and applicable to their own clinic settings. This type of critical insight requires familiarity with basic principles of good study design and with biostatistical logic and procedures. Unfortunately, recent studies have demonstrated that physicians9 concepts regarding statistics are often inaccurate, and even more disturbing, that readers are often willing to draw conclusions unsupported by the available data.1,2 Some authorities have therefore recommended remedial statistical training for physicians by means of increased attention to statistical issues in biomedical journals. The question of exactly which statistical concepts and techniques need to be mastered, however, remains largely unanswered. On this account, I reviewed several volumes of Pediatrics to determine which statistical techniques have appeared regularly, and whether the frequency and intensity of statistical analysis have recently changed enough that a familiarity with biostatistics that was adequate a few years ago may no longer be sufficient. I surveyed the scientific reports in volumes 9 (1952),29 (1962), 49(1972), and 69 (1982). I excluded editorials, book reviews, correspondence, and the like, and I classified remaining articles as review articles, case reports, or research reports.
Is there a startup wage premium? Evidence from MIT graduates

Abstract While startups are the center of extensive policy discussion given their outsized role in job creation, it is not clear whether they create high quality jobs relative to incumbent firms. This paper investigates the wage differential between venture capital-backed startups and established firms, given that the two firm types compete for talent. Using data on MIT graduates, I find that non-founder employees at VC-backed startups earn roughly 10% higher wages than their counterparts at established firms. To account for unobserved heterogeneity across workers, I exploit the fact that many MIT graduates receive multiple job offers. I find that wage differentials are statistically insignificant from zero when individual fixed effects are included. This implies that much of the startup wage premium in the cross-section can be attributed to selection, and that VC-backed startups pay competitive wages for talent. To unpack the selection mechanism, I show that individual preferences for risk as well as challenging work strongly predict entry into VC-backed startups.
Addressing the Digital Divide in Contemporary Biology: Lessons from Teaching UNIX

Life and medical science researchers increasingly rely on applications that lack a graphical interface. Scientists who are not trained in computer science face an enormous challenge analyzing high-throughput data. We present a training model for use of command-line tools when the learner has little to no prior knowledge of UNIX.
EXPERIMENTAL STUDY ON COMPLEX MODES OF AN END-DAMPED CONTINUOUS BEAM

The complex modes of an end-damped cantilevered beam are studied as an experimental example of a non-modally damped continuous system. An eddy-current damper was applied considering its noncontact and linear properties. The state-variable modal decomposition (SVMD) is applied to extract the modes from the impact responses in the cantilevered beam experiments. Characteristics of the mode shapes and modal damping are examined for various values of the damping coefficient. The modal frequencies and mode shapes obtained from the experiments have a good consistency with the results of the finite-element model. The variation of damping ratio and modal nonsynchronicity with varying damping coefficient also follow the prediction of the model. Over the range of damping coefficients studied in the experiments, we observe a maximum damping ratio in the lowest underdamped mode, which correlates with the maximum modal nonsynchronicity. Complex orthogonal decomposition (COD) is applied in comparison to the modal idenfication results obtained from SVMD.Copyright © 2015 by ASME
Geographic Cross-Sectional Fiscal Spending Multipliers: What Have We Learned?

A geographic cross-sectional fiscal spending multiplier measures the effect of an increase in spending in one region of a monetary union. Empirical studies of such multipliers have proliferated. I review this research and what the evidence implies for national multipliers. Based on an updated analysis of the ARRA and a survey of empirical studies, my preferred point estimate for a cross-sectional multiplier is 1.8. The paper also discusses conditions under which the cross-sectional multiplier provides a rough lower bound for the national, no-monetary-policy-response multiplier. Putting these elements together, the cross-sectional evidence suggests a national no-monetary-policy-response multiplier of 1.7 or above.
Drought impacts to water footprints and virtual water transfers of the Central Valley of California

The Central Valley of California is one of the most productive agricultural locations in the world, which is made possible by a complex and vast irrigation system. Beginning in 2012, California endured one of the worst droughts in its history. Local impacts of the drought have been evaluated, but it is not yet well understood how the drought reverberated through the global food system. Here, we quantify drought impacts to the water footprint (WF) of agricultural production and virtual water transfers (VWT) from the Central Valley of California. To do this, we utilize high-resolution spatial and temporal datasets and a crop model from pre-drought conditions (2011) through three years of exceptional drought (2012-2014). Despite a 12% reduction in harvested area, the WF of agricultural production in the Central Valley increased by 3%. This was due to greater crop water requirements from higher temperatures and a shift to more water-intensive orchard and vine crops. The groundwater WF increased from 7.00 km3 in 2011 to 13.63 km3 in 2014, predominantly in the Tulare Basin. Transfers of food commodities declined by 1% during the drought, yet total VWT increased by 3% (0.51 km3). From 2011 to 2014, groundwater VWT increased by 3.42 km3, offsetting the 0.94 km3 reduction in green VWT and the 1.96 km3 decrease in surface VWT. During the drought, local and global consumers nearly doubled their reliance on the Central Valley Aquifer. These results indicate that drought may strengthen the telecoupling between groundwater withdrawals and distant consumers of agricultural commodities.
Distributed Control: Status and Opportunities

Abstract Goals of improved productivity, efficiency, and product quality have motivated a continuing development over the years of automatic control theory and practice in industrial applications. A brief historical account of this development leads to a discussion of the current status of distributed control as a natural stage in the evolution toward complete integrated control of an industrial plant. The historical perspective also provides background for an examination of trends and opportunities in distributed control. Present generation microprocessor-based distributed control systems are described in terms of their generic features and attributes. Reference to limitations of these systems with respect to the goal of achieving implementable, cost effective and reliable integrated systems control motivates discussion of some current research areas and expected future developments. Finally, a review of the hierarchical control approach is presented. This provides a conceptual framework for organizing the elements of the distributed system for integration of the many diverse information processing, decision-making and control functions that are involved in a total plant control.
To the theory of viscosity solutions for uniformly elliptic Isaacs equations

We show how a theorem about the solvability in C 1,1 C 1 , 1 of special Isaacs equations can be used to obtain existence and uniqueness of viscosity solutions of general uniformly nondegenerate Isaacs equations. We apply it also to establish the C 1+χ C 1 + χ regularity of viscosity solutions and show that finite-difference approximations have an algebraic rate of convergence. The main coefficients of the Isaacs equations are supposed to be in C γ C γ with γ slightly less than 1/2.
Farmers Who Don't Farm: The Curious Rise of the Zero-Sales Farmer

While researchers have extensively studied the growth in the number of small farms between 1982 and 2012 reported in the Census of Agriculture (COA), there has been little discussion of trends among farm operators who do not sell any agri­cultural products. Using previously unreleased COA data collected between 1982 and 2012, this research empirically examines these “zero-sales farmers” for the first time. There was a large increase in the number of zero-sales farmers from 104,000 in 1982 to 466,000 in 2012, as well as a remarkable rise in their share of the farming popu­lation, from 5 percent in 1982 to 22 percent in 2012. Women and minority farmers were dispro­portionately likely to be zero-sales operators: at least 30 percent of women, Native American, and black farmers reported no sales in 2012. Older and beginning farmers were also more likely to report zero sales in 2012 than younger and experienced ones, respectively. Zero-sales farmers dramatically influenced recent census data on farm income, farm size, and operator age, among other results, due to their substantial share of the overall population. In order to effectively utilize COA data, practitioners, policymakers, and researchers should include zero-sales farms in their analyses. There are several steps the U.S. Depart­ment of Agriculture (USDA) can take to make information about zero-sales farmers more readily available and widely understood, such as introducing a zero-sales category in the census results.
Endothelial STAT3 Modulates Protective Mechanisms in a Mouse Ischemia-Reperfusion Model of Acute Kidney Injury

STAT3 is a transcriptional regulator that plays an important role in coordinating inflammation and immunity. In addition, there is a growing appreciation of the role STAT3 signaling plays in response to organ injury following diverse insults. Acute kidney injury (AKI) from ischemia-reperfusion injury is a common clinical entity with devastating consequences, and the recognition that endothelial alterations contribute to kidney dysfunction in this setting is of growing interest. Consequently, we used a mouse with a genetic deletion of Stat3 restricted to the endothelium to examine the role of STAT3 signaling in the pathophysiology of ischemic AKI. In a mouse model of ischemic AKI, the loss of endothelial STAT3 signaling significantly exacerbated kidney dysfunction, morphologic injury, and proximal tubular oxidative stress. The increased severity of ischemic AKI was associated with more robust endothelial-leukocyte adhesion and increased tissue accumulation of F4/80+ macrophages. Moreover, important proximal tubular adaptive mechanisms to injury were diminished in association with decreased tissue mRNA levels of the epithelial cell survival cytokine IL-22. In aggregate, these findings suggest that the endothelial STAT3 signaling plays an important role in limiting kidney dysfunction in ischemic AKI and that selective pharmacologic activation of endothelial STAT3 signaling could serve as a potential therapeutic target.
Airway Mucus and Asthma: The Role of MUC5AC and MUC5B.

Asthma is characterized by mucus abnormalities. Airway epithelial hyperplasia and metaplasia result in changes in stored and secreted mucin and the production of a pathologic mucus gel. Mucus transport is impaired, culminating in mucus plugging and airway obstruction—a major cause of morbidity in asthma. The polymeric mucins MUC5AC and MUC5B are integral components of airway mucus. MUC5AC and MUC5B gene expression is altered in asthma, and recent work sheds light on their contribution to asthma pathogenesis. Herein, we review our current understanding of the role of MUC5AC and MUC5B in mucus dysfunction in asthma.
A Statistically-Oriented Asymmetric Localization (SOAL) Model for Neuronal Outgrowth Patterning by Caenorhabditis elegans UNC-5 (UNC5) and UNC-40 (DCC) Netrin Receptors

Neurons extend processes that vary in number, length, and direction of "outgrowth". Extracellular cues help determine outgrowth patterns. In Caenorhabditis elegans, neurons respond to the extracellular UNC-6 (netrin) cue via UNC-40 (DCC) and UNC-5 (UNC5) receptors. Previously, we presented evidence that UNC-40 asymmetric localization at the plasma membrane is self-organizing, and that UNC-40 can localize and mediate outgrowth at randomly selected sites. Here, we provide further evidence for a statistically-oriented asymmetric localization (SOAL) model in which UNC-5 receptor activity affects patterns of axon outgrowth by regulating UNC-40 asymmetric localization. According to the SOAL model, the direction of outgrowth activity fluctuates across the membrane over time. Random walk modeling predicts that increasing the degree to which the direction of outgrowth fluctuates will decrease the outward displacement of the membrane. By differentially affecting the degree to which the direction of outgrowth activity fluctuates over time, extracellular cues can produce different rates of outgrowth along the surface and create patterns of "extension". Consistent with the SOAL model, we show that unc-5 mutations alter UNC-40 asymmetric localization, increase the degree to which the direction of outgrowth fluctuates, and reduce the extent of outgrowth in multiple directions relative to the source of UNC-6 These results are inconsistent with current models, which predict that UNC-5 mediates a "repulsive" response to UNC-6 Genetic interactions suggest that UNC-5 acts through the UNC-53 (NAV2) cytoplasmic protein to regulate UNC-40 asymmetric localization in response to both the UNC-6 and EGL-20 (Wnt) extracellular cues.
The Asymmetric Impact of Customer Information Portability on Service Competition: Evidence from the Global Wireless Industry

We study the impact of customer information portability on market competition in customerâ€ centric, technologyâ€ intensive service industries. By allowing customer information to be transferrable among service providers, portability in theory may help reduce switching costs and promote competition. Yet the actual consequences are unclear. To investigate this issue, we focus on the global wireless industry, and examine the impact of mobile number portability (MNP) policy. We construct a duopoly model with heterogeneous switching costs, which predicts that the market share of the large firm will shrink after MNP, while the average price may depend on firmsâ€™ customer base composition. We test these hypotheses empirically on a panel dataset of 218 wireless operators in 52 countries over 6Â years. We find relative market share gains for small firms and reductions for large firms under MNP. However, large firms can maintain higher prices than small firms. Probing deeper into customer segmentation, we find that on average, the share of contract customers increases for large firms after MNP, while it decreases for small firms. Large firms are able to retain higherâ€ value contract customers while small firms tend to attract lowerâ€ value â€œpayâ€ asâ€ youâ€ goâ€ customers. Contrary to the policy intention, large firms tend to remain dominant, and MNP is incapable of changing this. In fact, contracts become even more important after MNP, highlighting the sticky â€œlockâ€ inâ€ effect of contracts. Our findings have broad applicability to other service industries (e.g., healthcare, financial services, and digital media), where policymakers are considering making customer information more portable in hopes of increasing competition.
Cultural Structures of Knowledge from Wikipedia Networks of First Links

Knowledge is useless without structure. While the classification of knowledge has been an enduring philosophical enterprise, it recently found applications in computer science, notably for artificial intelligence. The availability of large databases allowed for complex ontologies to be built automatically, for example by extracting structured content from Wikipedia. However, this approach is subject to manual categorization decisions made by online editors. Here we show that an implicit classification hierarchy emerges spontaneously on Wikipedia. We study the network of first links between articles, and find that it centers on a core cycle involving concepts of fundamental classifying importance. We argue that this structure is rooted in cultural history. For European languages, articles like Philosophy and Science are central, whereas Human and Earth dominate for East Asian languages. This reflects the differences between ancient Greek thought and Chinese tradition. Our results reveal the powerful influence of culture on the intrinsic architecture of complex data sets.
Are long commutes short on benefits? Commute duration and various manifestations of well-being

Abstract Commuting comes with costs, in terms of money, the opportunity cost of time, emotional burdens, and danger. Yet Americans take on considerably longer commutes than are strictly necessary. This suggests that longer commutes must have benefits, or that many people who take on long commutes are not maximizing their utility. This research seeks evidence for compensation for longer-duration commuting. It finds four possible sources. First, longer commutes are associated with higher wages. Second, longer commutes are associated with higher rates of homeownership, possibly in part because they facilitate suburban living. Third, long commutes may benefit spouses, since marriage is associated with longer commutes, although there is no association between commute duration and the presence of children in the household. Fourth, spouses of those with longer commutes are less likely to work, which appears to be due in part to higher wages for the worker. However, there is no evidence that a longer commute is associated with higher wages for the commuter’s spouse when the spouse works. Longer commute trips are not associated with poorer mood during the trip, but also are not associated with more emotionally fulfilling work. Finally, commute duration is not associated with life satisfaction, perhaps because the net benefits and costs of commutes are roughly equal across varying commute durations, or because the burdens and benefits of the commute are not strong enough to impact as broad a construct as life satisfaction. The absence of an association between well-being and commute duration suggests that people are doing a reasonable job of maximizing their utility when selecting home and work locations.
A Saturation Mutagenesis Approach to Understanding PTEN Lipid Phosphatase Activity and Genotype-Phenotype Relationships.

Phosphatase and tensin homolog (PTEN) is a tumor suppressor frequently mutated in diverse cancers. Germline PTEN mutations are also associated with a range of clinical outcomes, including PTEN hamartoma tumor syndrome (PHTS) and autism spectrum disorder (ASD). To empower new insights into PTEN function and clinically relevant genotype-phenotype relationships, we systematically evaluated the effect of PTEN mutations on lipid phosphatase activity in vivo. Using a massively parallel approach that leverages an artificial humanized yeast model, we derived high-confidence estimates of functional impact for 7,244 single amino acid PTEN variants (86% of possible). We identified 2,273 mutations with reduced cellular lipid phosphatase activity, which includes 1,789 missense mutations. These data recapitulated known functional findings but also uncovered new insights into PTEN protein structure, biochemistry, and mutation tolerance. Several residues in the catalytic pocket showed surprising mutational tolerance. We identified that the solvent exposure of wild-type residues is a critical determinant of mutational tolerance. Further, we created a comprehensive functional map by leveraging correlations between amino acid substitutions to impute functional scores for all variants, including those not present in the assay. Variant functional scores can reliably discriminate likely pathogenic from benign alleles. Further, 32% of ClinVar unclassified missense variants are phosphatase deficient in our assay, supporting their reclassification. ASD-associated mutations generally had less severe fitness scores relative to PHTS-associated mutations (p = 7.16 × 10−5) and a higher fraction of hypomorphic mutations, arguing for continued genotype-phenotype studies in larger clinical datasets that can further leverage these rich functional data.
Relating the structure factors of two-dimensional materials in planar and spherical geometries

Scattering structure factors provide essential insight into material properties and are routinely obtained in experiments, computer simulations, and theoretical analyses. Different approaches favor different geometries of the material. In case of lipid bilayers, scattering experiments can be performed on spherical vesicles, while simulations and theory often consider planar membrane patches. We derive an approximate relationship between the structure functions of such a material in planar and spherical geometries. We illustrate the usefulness of this relationship in a case study of a Gaussian material that supports both homogeneous and microemulsion phases. Within its range of applicability, this relationship enables a model-free comparison of structure factors of the same material in different geometries.
Phased array antenna for the mitigation of UAS interference

The growing demand for Unmanned Aerial Systems (UAS) operating beyond the line of sight (BLOS) has resulted in an increased interest in using existing commercial satellite communication capabilities for UAS command and control (C2) communications. The World Radiocommunication Conference in 2015 designated portions of Ku-Band and Ka-Band fixed satellite service (FSS) spectrum to support UAS C2 communications, provided that potential interference with existing co-allocated users in these bands is addressed. As the user base in this new spectrum allocation expands, there is an increased potential for interference with existing terrestrial communication systems operating under fixed service (FS) allocations. The portion of Ka-Band spectrum allocated for UAS C2 avoids significant interference issues, but the Ku-Band allocation contains a co-primary F S allocation, creating potential interference problems. Therefore, UAS must identify solutions to avoid interfering with these existing FS ground sites while maintaining good links with satellite constellations. UAS operating with conventional fixed feed parabolic antennas will have difficulty in meeting interference thresholds, especially at high latitudes where the antennas will operate with low elevation angles. As a means of addressing this limitation, NASA is investigating the use of a phased array antenna to enable mitigation of interference into ground-based FS receivers. In this paper, a novel lightweight conformal phased array antenna will be presented that can use null-steering and/or beam shaping to avoid ground interference while simultaneously providing strong satellite microwave links for communications. The reduced weight of this design and ability to integrate into the fuselage of smaller UAS platforms will also be discussed as a potential solution to provide BLOS operation via spectrum sharing for an expanding user base. This paper will review design aspects of the conformal phased array antenna, describe the intended benefits in reducing interference with FS ground stations, and describe phased array development and test plans.
Cheater-altruist synergy in public goods games

Much research has focused on the deleterious effects of free-riding in public goods games, and a variety of mechanisms that suppress cheating behavior. Here we argue that under certain conditions cheating can be beneficial to the population. In a public goods game, cheaters do not pay for the cost of the public goods, yet they receive the benefit. Although this free-riding harms the entire population in the long run, the success of cheaters may aid the population when there is a common enemy that antagonizes both cooperators and cheaters. Here we study models of the interactions between tumor cells, which play a public goods game, and the immune system. We investigate three population dynamics models of cancer growth combined with a model of effector cell dynamics. We show that under a public good with a limiting benefit, the presence of cheaters aids the tumor in overcoming immune system suppression, and explore the parameter space wherein it occurs. The mechanism of this phenomenon is that a polymorphism of cheaters and altruists optimizes the average growth rate of the tumor, which is what determines whether or not the immune response is overcome. Our results give support for a possible synergy between cooperators and cheaters in ecological public goods games.
Hypersonic shock wave transitional boundary layer interactions - A review

Abstract Hypersonic shock wave transitional boundary layer interactions can result in significantly greater peak surface heat transfer than laminar or turbulent interactions. Consequently, the understanding of the flowfield structure of hypersonic shock wave transitional boundary layer interactions is important. Moreover, the capability to predict the mean and fluctuating aerothermodynamic loading due to such interactions is needed for effective design of hypersonic vehicles. A review of hypersonic shock wave transitional boundary layer interaction research since 1993 is presented. Significant progress has been achieved in the understanding of the flowfield structure. The most promising prediction methodology is Direct Numerical Simulation (DNS); however, DNS requires dynamic (i.e., time varying) inflow boundary conditions for five flow variables (i.e., three components of velocity, and two thermodynamic variables), and such experimental data is presently infeasible. Additional research is needed to understand the effect of assumed dynamic inflow boundary conditions on DNS prediction of aerothermodynamic loads.
Randomised trials in education in the USA

Background and purpose: Studies of education and learning that were described as experiments have been carried out in the USA by educational psychologists since about 1900. In this paper, we discus...
Deepcode: Feedback Codes via Deep Learning

The design of codes for communicating reliably over a statistically well defined channel is an important endeavor involving deep mathematical research and wide- ranging practical applications. In this work, we present the first family of codes obtained via deep learning, which significantly beats state-of-the-art codes designed over several decades of research. The communication channel under consideration is the Gaussian noise channel with feedback, whose study was initiated by Shannon; feedback is known theoretically to improve reliability of communication, but no practical codes that do so have ever been successfully constructed. We break this logjam by integrating information theoretic insights harmoniously with recurrent-neural-network based encoders and decoders to create novel codes that outperform known codes by 3 orders of magnitude in reliability. We also demonstrate several desirable properties in the codes: (a) generalization to larger block lengths; (b) composability with known codes; (c) adaptation to practical constraints. This result also presents broader ramifications to coding theory: even when the channel has a clear mathematical model, deep learning methodologies, when combined with channel specific information-theoretic insights, can potentially beat state-of-the-art codes, constructed over decades of mathematical research.