cssi/SciSciGPT-SciSciNet huggingface dataset:
Overstating and understating interaction results in international business research

Approximately one-third of international business (IB) articles include conditional hypotheses, yet the vast majority risk errors in testing or interpreting the results. Scholars typically restrict their empirical analysis to the coefficient of the interaction term in the regression, exposing themselves to the hazard of overstating or understating results. To mitigate the risk of misstating, we advocate that IB scholars also evaluate the statistical significance of the marginal effect of the primary independent variable over the range of values of the moderating variable. We demonstrate that overstating results can occur when the interaction term coefficient is statistically significant but the marginal effect is not significantly different from zero for some value(s) of the moderating variable. Understating can occur when the interaction term coefficient is not statistically significant, but the marginal effect is statistically different from zero for some value(s) of the moderating variable. In this article, we describe, using simulated data, these two possibilities associated with testing conditional hypotheses, and offer practical guidance for IB scholars.
Why Are There So Many Lawyers in Congress

For centuries, scholars have puzzled over why so many lawyers are elected to Congress. This paper draws on a wealth of new data to weigh in on why this age-old representation imbalance has endured. While lawyers enter politics at much higher rates, self-selection at best offers a partial explanation. Conditional on running, lawyers win at twice the rate of candidates from other backgrounds. Contrary to prevailing theories in the literature, voters do not reward candidates with backgrounds in law. Rather, lawyers win because of a sizable competitive advantage in early fundraising, owing in large part to their professional networks. This study has important implications about who runs for office, who wins, and the consequences for the demographic composition of Congress. It also identifies an underexplored mechanism by which the U.S. system of campaign finance sustains deep representational imbalances.
Historical Prevalence of Infectious Diseases, Cultural Values, and the Origins of Economic Institutions

It is widely believed that economic institutions such as competitive markets, the banking system, and the structure of property rights are essential for economic development. But why economic institutions vary across countries and what are their deep origins is still a question that is widely debated in the developmental economics literature. In this study, we provide an empirical test for the provocative hypothesis that the prevalence of infectious diseases influenced the formation of personality traits, cultural values, and even morality at the regional level (the so called Parasite- Stress Theory of Values and Sociality), which then shaped economic institutions across countries. Using the prevalence of pathogens as an instrument for cultural traits such as individualism, we show in a two-stage least squares analysis that various economic institutions, measured by different areas of the index of Economic Freedom by the Heritage Foundation, have their deep origins in the historical prevalence of infectious diseases across countries. Our causal identification strategy suggests that cultural values affect economic institutions even after controlling for a number of confounding variables, geographic controls, and for different sub-samples of countries. We further show that the results are robust to four alternative measures of economic and political institutions.
Recent Advances in Ultra-high Vacuum Technology

Abstract The two major directions for advances in ultra-high vacuum technology are (1) the attainment and measurement of pressures below 10−10 mm Hg, and (2) the development of large ultra-high vacuum systems. New vacuum components have recently been introduced which are of great value in both of these directions. Of particular interest are the development of ionization gauges capable of reading pressures below 10−12mm Hg and the design of systems several orders of magnitude larger than those heretofore described. Contributions of a number of workers in this field are briefly discussed. One of the most important recent developments is the “getter-ion” pump as a means of achieving both lower pressures and higher pumping speeds. It has been shown that very simple “getter-ion” pumps are possible which can replace diffusion pumps to achieve pressures down to the 10−10mm Hg region. Despite this achievement there are many unanswered questions involving the underlying mechanisms of sorption and desorption for neutral and activated molecular gases. Preliminary experiments have been made on the sticking probability of certain gases on titanium and the effect of an adjacent ionizing electron beam.
Systemic Injection of RPE65-Programmed Bone Marrow-Derived Cells Prevents Progression of Chronic Retinal Degeneration

Bone marrow stem and progenitor cells can differentiate into a range of non-hematopoietic cell types, including retinal pigment epithelium (RPE)-like cells. In this study, we programmed bone marrow-derived cells (BMDCs) ex vivo by inserting a stable RPE65 transgene using a lentiviral vector. We tested the efficacy of systemically administered RPE65-programmed BMDCs to prevent visual loss in the superoxide dismutase 2 knockdown (Sod2 KD) mouse model of age-related macular degeneration. Here, we present evidence that these RPE65-programmed BMDCs are recruited to the subretinal space, where they repopulate the RPE layer, preserve the photoreceptor layer, retain the thickness of the neural retina, reduce lipofuscin granule formation, and suppress microgliosis. Importantly, electroretinography and optokinetic response tests confirmed that visual function was significantly improved. Mice treated with non-modified BMDCs or BMDCs pre-programmed with LacZ did not exhibit significant improvement in visual deficit. RPE65-BMDC administration was most effective in early disease, when visual function and retinal morphology returned to near normal, and less effective in late-stage disease. This experimental paradigm offers a minimally invasive cellular therapy that can be given systemically overcoming the need for invasive ocular surgery and offering the potential to arrest progression in early AMD and other RPE-based diseases.
Nanophotonic lithium niobate electro-optic modulators.

Since the emergence of optical fiber communications, lithium niobate (LN) has been the material of choice for electro-optic modulators, featuring high data bandwidth and excellent signal fidelity. Conventional LN modulators however are bulky, expensive and power hungry, and cannot meet the growing demand in modern optical data links. Chip-scale, highly integrated, LN modulators could offer solutions to this problem, yet the fabrication of low-loss devices in LN thin films has been challenging. Here we overcome this hurdle and demonstrate monolithically integrated LN electro-optic modulators that are significantly smaller and more efficient than traditional bulk LN devices, while preserving LN’s excellent material properties. Our compact LN electro-optic platform consists of low-loss nanoscale LN waveguides, micro-ring resonators and miniaturized Mach-Zehnder interferometers, fabricated by directly shaping LN thin films into sub-wavelength structures. The efficient confinement of both optical and microwave fields at the nanoscale dramatically improves the device performances featuring a half-wave electro-optic modulation efficiency of 1.8 V∙cm while operating at data rates up to 40 Gbps. Our monolithic LN nanophotonic platform enables dense integration of high-performance active components, opening new avenues for future high-speed, low power and cost-effective communication networks.
Rigid body dynamic simulation with line and surface contact

In this paper, we develop a principled method to model line and surface contact with point contacts that is consistent with physics-based models of surface (line) contact. We solve the contact detection and dynamic simulation step simultaneously by formulating the problem as a mixed nonlinear complementarity problem. This allows us to simultaneously compute the centre of pressure as well as the forces at the centre of pressure (consistent with the friction model) along with the configuration and velocities of the rigid objects. We present a geometrically implicit time-stepping scheme for dynamic simulation for contacts between two bodies with convex contact area, which includes 2D line contact, 3D surface contact, and 3D line contact. We prove that for surface and line contact, for any value of the velocity of center of mass of the object, there is a unique solution for contact point and contact wrench that satisfies the discrete-time equations of motion. For pure translation and pure rotation, we show that there is a closed form solution for each discrete time-step if the contact mode does not change. Simulation examples are shown to demonstrate the validity of our approach and show that with our approach we can seamlessly transition between point, line, and surface contacts.
Non-singular black holes in massive gravity: time-dependent solutions

When starting with a static, spherically-symmetric ansatz, there are two types of black hole solutions in dRGT massive gravity: (i) exact Schwarzschild solutions which exhibit no Yukawa suppression at large distances and (ii) solutions in which the dynamical metric and the reference metric are simultaneously diagonal and which inevitably exhibit coordinate-invariant singularities at the horizon. In this work we investigate the possibility of black hole solutions which can accommodate both a nonsingular horizon and Yukawa asymptotics. In particular, by adopting a time-dependent ansatz, we derive perturbative analytic solutions which possess non-singular horizons. These black hole solutions are indistinguishable from Schwarzschild black holes in the limit of zero graviton mass. At finite graviton mass, they depend explicitly on time. However, we demonstrate that the location of the apparent horizon is not necessarily time-dependent, indicating that these black holes are not necessarily accreting or evaporating (classically). In deriving these results, we also review and extend known results about static black hole solutions in massive gravity.
High-Efficiency Impedance Control Network Resonant DC–DC Converter With Optimized Startup Control

This paper presents an improved efficiency impedance control network (ICN) resonant dc–dc converter that maintains zero-voltage switching (ZVS) and near-zero-current switching (ZCS) across wide ranges in input and output voltages and output power. The improvement in efficiency in this burst mode operated converter is achieved through an optimized startup control that minimizes its startup transient and helps the converter maintain ZVS and near-ZCS operation, even during the startup for each burst cycle. This optimization of startup is made possible by a new accurate time domain model for the ICN converter waveforms that helps reduce the number of non-ZVS transitions by 75%. A prototype 200 W, 500 kHz ICN resonant converter designed to operate over an input voltage range of 25–40 V and output voltage range of 250–400 V is built and tested. The prototype ICN converter achieves a peak efficiency of 97.2% and maintains greater than 96.2% full power efficiency at 250 V output voltage across the nearly 2:1 input voltage range, and maintains full power efficiency above 94.6% across its full input and output voltage range. The converter also maintains efficiency above 93.6% over a 10:1 output power range across its full input and output voltage range.
Bayesian Repulsive Gaussian Mixture Model

We develop a general class of Bayesian repulsive Gaussian mixture models that encourage well-separated clusters, aiming at reducing potentially redundant components produced by independent priors f...
Recurrent collective classification

We propose a new method for training iterative collective classifiers for labeling nodes in network data. The iterative classification algorithm (ICA) is a canonical method for incorporating relational information into classification. Yet, existing methods for training ICA models rely on the assumption that relational features reflect the true labels of the nodes. This unrealistic assumption introduces a bias that is inconsistent with the actual prediction algorithm. In this paper, we introduce recurrent collective classification (RCC), a variant of ICA analogous to recurrent neural network prediction. RCC accommodates any differentiable local classifier and relational feature functions. We provide gradient-based strategies for optimizing over model parameters to more directly minimize the loss function. In our experiments, this direct loss minimization translates to improved accuracy and robustness on real network data. We demonstrate the robustness of RCC in settings where local classification is very noisy, settings that are particularly challenging for ICA.
The Multi-user Security of Double Encryption

It is widely known that double encryption does not substantially increase the security of a block cipher. Indeed, the classical meet-in-the middle attack recovers the 2k-bit secret key at the cost of roughly \(2^k\) off-line enciphering operations, in addition to very few known plaintext-ciphertext pairs. Thus, essentially as efficiently as for the underlying cipher with a k-bit key.
High Efficiency Graphene Solar Cells by Chemical Doping

We demonstrate single layer graphene/n-Si Schottky junction solar cells that under AM1.5 illumination exhibit a power conversion efficiency (PCE) of 8.6%. This performance, achieved by doping the graphene with bis(trifluoromethanesulfonyl)amide, exceeds the native (undoped) device performance by a factor of 4.5 and is the highest PCE reported for graphene-based solar cells to date. Current–voltage, capacitance–voltage, and external quantum efficiency measurements show the enhancement to be due to the doping-induced shift in the graphene chemical potential that increases the graphene carrier density (decreasing the cell series resistance) and increases the cell’s built-in potential (increasing the open circuit voltage) both of which improve the solar cell fill factor.
CLINICAL AND RADIOGRAPHIC RESULTS OF A HIGHLY POROUS ACETABULAR SHELL

1) INTRODUCTION Acetabular fixation in cementless total hip arthroplasty (THA) relies on new technology for stability and survivorship of the implant. A highly porous 3D titanium coating was developed with a biologically inspired pore structure to improve initial friction fixation with mechanical stability and long term biological fixation. Ongoing research is investigating potential radiographic phenomenons these coatings produce, resulting in the presence of lucent lines. The purpose of this study was to evaluate clinical and radiographic outcomes of a 3D highly porous-coated titanium acetabular shell. 2) METHODS One hundred and sixty-two cases as part of a non-randomized, post-market, multicenter study received a primary cementless THA. Clinical outcomes including the Harris Hip Score (HHS), Lower Extremity Activity Scale (LEAS), Short Form 12 (SF12), and EuroQol 5D Score (EQ-5D) were collected preoperatively and at six weeks, one year postoperative. Additionally, radiographs, radiographic parameters and techniques were analyzed for institutional differences. 3) RESULTS Significant postoperative improvements were seen in pain, function and quality of life outcomes through one year. The HHS improved significantly (p Figure 1 ), with 53.4% of patients scoring Excellent or Good at six weeks and 87.5% at one year ( Figure 2 ). Pain and physical functioning reported by the SF-12, EQ-5D and LEAS showed further clinical improvements at one year ( Figure 1 ). Radiographically, 9.5% of cases reviewed displayed ‘radiolucent lines’ of less than 2mm in all three acetabular zones at six weeks. These cases only displayed radiolucent lines in one zone at the one year timepoint ( Figure 3 ). Patients with radiolucent lines reported an average HHS score of 77 and 96 at six weeks and one year, respectively, with no radiographic failures or any revisions to date. The radiographic parameters and techniques were collected to analyze differences between the imaging techniques between institutions. Institutions utilizing digital radiography with an automatic exposure control technique, had cases where ‘radiolucent lines’ were present. One institution utilizing computed radiography with a manual technique did not have any cases display ‘radiolucent lines’. 4) DISCUSSION and CONCLUSION Despite the appearance of transient radiographic lucent lines, patients in this study have shown positive clinical outcomes and initial stability through one year postoperative. These results do not correlate with the presence of radiolucent lines. Additionally, there may be a correlation between the imaging techniques and the presence of ‘radiolucent lines.’ As this device is still widely implanted using the same surgical technique, longer follow-up is needed to confirm a true biologic fixation and survivorship of the shell.
Cholangiocarcinoma arising in congenital hepatic fibrosis: a case report

Congenital hepatic fibrosis (CHF) is a morphologic entity characterized by (1) abnormal fibrous septation, (2) preservation of the basic lobular architecture, and (3) hyperplasia and dilatation of bile ductules. Congenital hepatic fibrosis may present as a cause of portal hypertension in adolescents, in young adults, and, rarely, in older adults. It is this form of the disorder that has been emphasized in the literature. However, CHF may also be seen in association with the infantile polycystic kidney syndrome. In the latter, the hepatic disorder is usually clinically silent. Cholangiocarcinoma is a rare complication of comgenital hepatic fibrosis, with only two previously documented cases reported, to our knowledge. We report a third case and suggest that CHF may represent a dysplastic hamartoma that, with prolonged survival, may eventuate in the development of intrahepatic biliary neoplasia.
They got mad skills : the effects of training on youth employability and resilience to the Ebola shock

This paper discusses a randomized control trial to measure the short-term impacts of a skills intervention among urban youth in Sierra Leone at the onset of the Ebola crisis. The intervention provided (i) technical skills training, plus on-the-job training; (ii) business skills training; and (iii) a mix of (i) and (ii). All groups received stipends and literacy and numeracy training. The findings support evidence that combining cash injections and skills training can stimulate employment and entrepreneurship. The program boosted household consumption and investments in housing and assets, thereby building resilience to the Ebola shock. The effects on cognitive and noncognitive skills were positive and heterogeneous. Youth with greater initial ability experienced more positive labor market and entrepreneurship investment impacts. Youth with less initial ability upgraded skills more extensively, although they channeled benefits into more consumption. These findings emphasize the role of basic safety nets and show that noncognitive tests may improve the targeting of skills interventions in fragile contexts. The results also confirm the age-malleability of noncognitive ability and suggest that, in low-ability contexts, the sensitive years for skill investments may reach into early adulthood.
Sequence text structure intervention during interactive book reading of expository picture books with preschool children with language impairment

This study explores the outcomes of an interactive book reading intervention featuring expository picture books. This small-group intervention was delivered by four practitioners (two early childhood special education teachers and two speech-language pathologists) three times per week for 8 weeks to 6 preschool-age children (3 years 1 month to 4 years 9 months) identified with language impairment. The intervention included use of language facilitation strategies during interactive book reading and extension activities after reading for promoting children’s understanding of signal words related to the sequence text structure (e.g. first, next, then, finally), academic vocabulary, and science topic knowledge related to plants (how plants grow, plant parts, plant needs). Outcomes indicated that practitioners increased their use of language facilitation strategies over the course of the intervention in both contexts of interactive book reading and extension activities. Children with language impairment made s...
The evolution of empathy research: Models, muddles, and mechanisms

The word empathy enters the English language in 1909, translated incompletely from German by a British-born psychologist interested in introspection. In the ensuing 100+ years, the term has been defined in a range of different ways by researchers and scholars. The biopsychosocial framework developed by George Engel comes closest to capturing empathy as a biological, psychological and social phenomenon. In this paper, I explore the psychological and social/communicative dimensions of empathy. Psychologists ask the question, How does the capacity for empathy vary across individuals? By contrast, interaction scholars ask, How is empathy communicated from one person (a healthcare provider) to another (a sufferer)? A communication focus involves the accuracy and impact of empathic communication as evidenced in a sufferer's response. The two views of empathy, as a quality or capacity or as co-created in interaction, are contradictory, and are a source of confusion and contentiousness in the research literature. As in theoretical physics, where an as yet unresolved 80year controversy has marked the debate about whether light is a particle or wave, research on empathy will likely remain paradoxical, unresolved and a source of creativity and innovation in the science and art of human caring.
Impact of increased renewables on natural gas markets in eastern United States

This paper explores the market structures of natural gas and electricity as well as the interdependence of natural gas prices and bids with increasing reliance on natural gas as the penetration of renewable energy resources increases in order to complement their intermittencies. In particular, the paper will attempt to answer the following two questions: What could the generation mix look like in 2030 with a renewable-rich generation landscape and how could this impact gas prices? How do gas-fired generator (GFG) generation volatility, their prices, and their bids for gas change between 2015 and 2030 with increased penetration of renewables? In order to answer these questions, computational models are derived using forecasting and regression analysis tools and an auction model.
The cerebellum does more than sensory prediction error-based learning in sensorimotor adaptation tasks

Individuals with damage to the cerebellum perform poorly in sensorimotor adaptation paradigms. This deficit has been attributed to impairment in sensory prediction error-based updating of an internal forward model, a form of implicit learning. These individuals can, however, successfully counter a perturbation when instructed with an explicit aiming strategy. This successful use of an instructed aiming strategy presents a paradox: In adaptation tasks, why do individuals with cerebellar damage not come up with an aiming solution on their own to compensate for their implicit learning deficit? To explore this question, we employed a variant of a visuomotor rotation task in which, before executing a movement on each trial, the participants verbally reported their intended aiming location. Compared with healthy control participants, participants with spinocerebellar ataxia displayed impairments in both implicit learning and aiming. This was observed when the visuomotor rotation was introduced abruptly (experiment 1) or gradually (experiment 2). This dual deficit does not appear to be related to the increased movement variance associated with ataxia: Healthy undergraduates showed little change in implicit learning or aiming when their movement feedback was artificially manipulated to produce similar levels of variability (experiment 3). Taken together the results indicate that a consequence of cerebellar dysfunction is not only impaired sensory prediction error-based learning but also a difficulty in developing and/or maintaining an aiming solution in response to a visuomotor perturbation. We suggest that this dual deficit can be explained by the cerebellum forming part of a network that learns and maintains action-outcome associations across trials.NEW & NOTEWORTHY Individuals with cerebellar pathology are impaired in sensorimotor adaptation. This deficit has been attributed to an impairment in error-based learning, specifically, from a deficit in using sensory prediction errors to update an internal model. Here we show that these individuals also have difficulty in discovering an aiming solution to overcome their adaptation deficit, suggesting a new role for the cerebellum in sensorimotor adaptation tasks.
Redistributive fiscal policies and business cycles in emerging economies

Abstract Government expenditures are pro-cyclical in emerging markets and counter-cyclical in developed economies. We show this pattern is most pronounced in social transfers which are also a large component of total government expenditures (28–39%). The discrepancy in the cyclicality of spending on goods and services is smaller, by contrast, and the category accounts for just 11–16% of total government expenditures. In a small open economy model, we find disparate social transfer policies can account for about half of the larger cyclical volatility of consumption relative to output in emerging economies compared to developed. We analyze how differences in tax policy and the nature of underlying inequality amplify or mitigate this result.
A Modal Reduction Method for Nonlinear Simulation of Flexible Spacecraft

Abstract This paper presents a modal truncation method that can be used to prepare the structural flexibility data required as input to flexible, multibody spacecraft simulation programs. The method allows one to truncate the stuctural models of each flexible body in the system such that the assembled system is free of undesired high frequency system modes. This truncation method enables reasonable simulation costs to be incurred while maintaining dynamic simulation fidelity in the frequency range of interest. A simple one-dimensional example is presented which provides a physical interpretation of the method's workings. In addition, results are presented from the application of the method to a complex spacecraft.
The Neuroendocrine Response to Multiple Trauma

The neuroendocrine response to multiple trauma is a coordinated, complex, changing response which has as its objective maintenance of life by preserving oxygen delivery and the mobilization and utilization of the synthetic and energetic substrates required by the body. The afferent system is composed of neural input from the various chemoceptors, nociceptors, and baroceptors which monitor normal bodily function, in addition to the effects of plasma factors directly on the brain (e.g., glucose and amino acids). The efferent system is composed of the autonomic nervous system and the output of the anterior and posterior pituitary and other hormones. The efferent response is shown by measurements of ACTH, arginine vasopressin, growth hormone, prolactin, norepinephrineepinephrine, and opiate peptides. This efferent output then modulates the response of the pancreatic islets with the observed changes in glucagon and insulin and of the adrenal glands with additional changes in the catechol-amines and cortisol. The renin-angiotensin-aldosterone system involving the kidney and adrenal gland is another responding system. The preceding relationships are discussed in some detail. Restoration of normal neuroendocrine function is best achieved by prompt restoration of blood volume, relief of pain and anxiety, restoration of normal food intake, excision of damaged tissue, and prevention of subsequent organ failure (e.g., pulmonary).
Cytogenetic Analysis in Renal Cell Carcinoma: Correlation With Tumor Aggressiveness

Twenty-eight tissue specimens from 26 patients with renal cell carcinoma were subjected to cytogenetic analysis using a newly developed combined method of enzymatic technique and short term tissue culture. Of the 28 tumor samples studied, 21 were chromosomally abnormal. Four (including two oncocytomas) were normal, and three did not grow in tissue culture. Of the 21 tumors with abnormal chromosomes, the most frequent abnormality was either trisomy or tetrasomy of chromosome 7 (18 of 21 tumors). In four of these tumors, trisomy 7 was the only visible abnormality. Ten tumors contained abnormalities of chromosome 3. Three showed a previously reported chromosome 3 interstitial deletion, five were hyperdiploid, and two revealed a monosomy 3. Of these 10 patients, six have had disease progression, compared to one of the 16 remaining patients without an abnormal chromosome 3. These data suggest that abnormalities of chromosome 7 represent a primary abnormality, and that when these abnormalities are present in association with abnormalities involving chromosome 3, they may correlate with a more aggressive clinical course and a corresponding higher stage of disease at diagnosis.
RNA Editing in Pathogenesis of Cancer

Several adenosine or cytidine deaminase enzymes deaminate transcript sequences in a cell type or environment-dependent manner by a programmed process called RNA editing. RNA editing enzymes catalyze A>I or C>U transcript alterations and have the potential to change protein coding sequences. In this brief review, we highlight some recent work that shows aberrant patterns of RNA editing in cancer. Transcriptome sequencing studies reveal increased or decreased global RNA editing levels depending on the tumor type. Altered RNA editing in cancer cells may provide a selective advantage for tumor growth and resistance to apoptosis. RNA editing may promote cancer by dynamically recoding oncogenic genes, regulating oncogenic gene expression by noncoding RNA and miRNA editing, or by transcriptome scale changes in RNA editing levels that may affect innate immune signaling. Although RNA editing markedly increases complexity of the cancer cell transcriptomes, cancer-specific recoding RNA editing events have yet to be discovered. Epitranscriptomic changes by RNA editing in cancer represent a novel mechanism contributing to sequence diversity independently of DNA mutations. Therefore, RNA editing studies should complement genome sequence data to understand the full impact of nucleic acid sequence alterations in cancer. Cancer Res; 77(14); 3733–9. ©2017 AACR.
Utility of the Abdominoinguinal Incision in the Resection of Lower Abdominal Tumors

The abdominoinguinal incision provides exposure and renders resectable large tumors located in the lower retroperitoneum, the area of external iliac vessels, and the wall of the pelvis. It is particularly useful for tumors manifesting fixation to these areas. It has been used successfully in 18 patients with malignant tumors and may be expected to increase substantially resectability of tumors in this area and to decrease the need for hemipelvectomy.
Plant organ evolution revealed by phylotranscriptomics in Arabidopsis thaliana

The evolution of phenotypes occurs through changes both in protein sequence and gene expression levels. Though much of plant morphological evolution can be explained by changes in gene expression, examining its evolution has challenges. To gain a new perspective on organ evolution in plants, we applied a phylotranscriptomics approach. We combined a phylostratigraphic approach with gene expression based on the strand-specific RNA-seq data from seedling, floral bud, and root of 19 Arabidopsis thaliana accessions to examine the age and sequence divergence of transcriptomes from these organs and how they adapted over time. Our results indicate that, among the sense and antisense transcriptomes of these organs, the sense transcriptomes of seedlings are the evolutionarily oldest across all accessions and are the most conserved in amino acid sequence for most accessions. In contrast, among the sense transcriptomes from these same organs, those from floral bud are evolutionarily youngest and least conserved in sequence for most accessions. Different organs have adaptive peaks at different stages in their evolutionary history; however, all three show a common adaptive signal from the Magnoliophyta to Brassicale stage. Our research highlights how phylotranscriptomic analyses can be used to trace organ evolution in the deep history of plant species.
Indistinguishability Obfuscation for Turing Machines: Constant Overhead and Amortization

We study the asymptotic efficiency of indistinguishability obfuscation (\(\mathsf {i}\mathcal {O}\)) on two fronts: Obfuscation size: Present constructions of indistinguishability obfuscation (\(\mathsf {i}\mathcal {O}\)) create obfuscated programs where the size of the obfuscated program is at least a multiplicative factor of security parameter larger than the size of the original program. In this work, we construct the first \(\mathsf {i}\mathcal {O}\) scheme for (bounded-input) Turing machines that achieves only a constant multiplicative overhead in size. The constant in our scheme is, in fact, 2. Amortization: Suppose we want to obfuscate an arbitrary polynomial number of (bounded-input) Turing machines \(M_1,\ldots ,M_n\). We ask whether it is possible to obfuscate \(M_1,\ldots ,M_n\) using a single application of an \(\mathsf {i}\mathcal {O}\) scheme for a circuit family where the size of any circuit is independent of n as well the size of any Turing machine \(M_i\). In this work, we resolve this question in the affirmative, obtaining a new bootstrapping theorem for obfuscating arbitrarily many Turing machines.
Online psychotherapy for depression

Technology-facilitated delivery of psychotherapy (e.g., via telephone, computer, or web) has been shown to be effective and may be cheaper, more
Do women CEOs face greater threat of shareholder activism compared to male CEOs? A role congruity perspective

We examine the glass cliff proposition that female CEOs receive more scrutiny than male CEOs, by investigating whether CEO gender is related to threats from activist investors in public firms. Activist investors are extraorganizational stakeholders who, when dissatisfied with some aspect of the way the firm is being managed, seek to change the strategy or operations of the firm. Although some have argued that women will be viewed more favorably than men in top leadership positions (so-called "female leadership" advantage logic), we build on role congruity theory to hypothesize that female CEOs are significantly more likely than male CEOs to come under threat from activist investors. Results support our predictions, suggesting that female CEOs may face additional challenges not faced by male CEOs. Practical implications and directions for future research are discussed. (PsycINFO Database Record
Olfactory experience primes the heat shock transcription factor HSF-1 to enhance the expression of molecular chaperones in C. elegans

Learning, a process by which animals modify their behavior as a result of experience, enables organisms to synthesize information from their surroundings to acquire resources and avoid danger. We showed that a previous encounter with only the odor of pathogenic bacteria prepared Caenorhabditis elegans to survive exposure to the pathogen by increasing the heat shock factor 1 (HSF-1)–dependent expression of genes encoding molecular chaperones. Experience-mediated enhancement of chaperone gene expression required serotonin, which primed HSF-1 to enhance the expression of molecular chaperone genes by promoting its localization to RNA polymerase II–enriched nuclear loci, even before transcription occurred. However, HSF-1–dependent chaperone gene expression was stimulated only if and when animals encountered the pathogen. Thus, learning equips C. elegans to better survive environmental dangers by preemptively and specifically initiating transcriptional mechanisms throughout the whole organism that prepare the animal to respond rapidly to proteotoxic agents. These studies provide one plausible basis for the protective role of environmental enrichment in disease.
DNA Unwinding Is the Primary Determinant of CRISPR-Cas9 Activity

Bacterial adaptive immunity utilizes RNA-guided surveillance complexes comprising Cas proteins together with CRISPR RNAs (crRNAs) to target foreign nucleic acids for destruction. Cas9, a type II CRISPR-Cas effector complex, can be programed with a single-guide RNA that base pairs with the target strand of dsDNA, displacing the non-target strand to create an R-loop, where the HNH and the RuvC nuclease domains cleave opposing strands. While many structural and biochemical studies have shed light on the mechanism of Cas9 cleavage, a clear unifying model has yet to emerge. Our detailed kinetic characterization of the enzyme reveals that DNA binding is reversible, and R-loop formation is rate-limiting, occurring in two steps, one for each of the nuclease domains. The specificity constant for cleavage is determined through an induced-fit mechanism as the product of the equilibrium binding affinity for DNA and the rate of R-loop formation.
What are the Visual Features Underlying Human Versus Machine Vision

Although Deep Convolutional Networks (DCNs) are approaching the accuracy of human observers at object recognition, it is unknown whether they leverage similar visual representations to achieve this performance. To address this, we introduce Clicktionary, a web-based game for identifying visual features used by human observers during object recognition. Importance maps derived from the game are consistent across participants and uncorrelated with image saliency measures. These results suggest that Clicktionary identifies image regions that are meaningful and diagnostic for object recognition but different than those driving eye movements. Surprisingly, Clicktionary importance maps are only weakly correlated with relevance maps derived from DCNs trained for object recognition. Our study demonstrates that the narrowing gap between the object recognition accuracy of human observers and DCNs obscures distinct visual strategies used by each to achieve this performance.
Europe as a Civilization: The Revolution of the Middle Ages & The Rise of the Universities

Although "Western Civilization" has long been a commonly used term, the idea of "Europe as a Civilization," I believe, needs articulation. This requires both a serviceable definition of a "civilization" and a historically and conceptually rich analysis of the formation of the European tradition. As I shall argue, Europe in the Middle Ages underwent a radical transformation that up to the present has been inadequately understood and insufficiently articulated.
Energy efficiency of membrane distillation up to high salinity: Evaluating critical system size and optimal membrane thickness

Abstract This study presents a comprehensive analytical framework to design efficient single-stage membrane distillation (MD) systems for the desalination of feed streams up to high salinity. MD performance is quantified in terms of energy efficiency (represented as a gained output ratio, or GOR) and vapor flux, both of which together affect the specific cost of pure water production. Irrespective of the feed salinity, permeate or conductive gap MD (P/CGMD) perform better than direct contact MD (DCMD) when the heat transfer resistance of the gap (in P/CGMD) is lower than that of the external heat exchanger in DCMD. Air gap MD’s (AGMD) better performance relative to the other configurations at high salinity and large system area can be explained in terms of its thicker ‘effective membrane’, which includes the air-gap region. CGMD and DCMD employing a thick membrane are also resilient to high salinity, similar to AGMD, while not being susceptible to the gap flooding that can harm AGMD’s performance. A method is described to simultaneously determine the cost-optimal membrane thickness and system size as a function of the ratio of specific costs of heat energy and module area. At low salinity and small system size, GOR rises and flux declines with an increase in membrane area. For salty feed solutions, there exists a critical system size beyond which GOR also begins to decline. Since both GOR and flux are lower, no economic rationale favors operation above this critical size, irrespective of the costs of thermal energy and system area. A closed-form analytical expression for this critical system area is derived as a function of the feed salinity and two dimensionless ratios of heat transfer resistances within the MD module.
Predicted max degree sampling: Sampling in directed networks to maximize node coverage through crawling

When studying large-scale networks, including the Web and computer networks, it is first necessary to collect appropriate data. There is a large body of literature on web crawling and network sampling in general; however, this work typically assumes that a query on a node either reveals all edges incident to that node (in the case of an undirected graph) or all edges outgoing from that node (e.g., in the case of a web crawler). There is relatively little work on sampling directed networks where incoming and outgoing edges may be obtained with separate queries. This type of sampling is relevant to networks like Twitter, in which the ‘Friends’ and ‘Follower’ connections are reciprocal relationships (i.e., if A is a follower of B, then B is a friend of A). In this paper we present Predicted Max Degree Sampling (PMD), a new method of sampling a directed network, with the objective of maximizing the total number of nodes observed. We consider two types of crawling, corresponding to the scenarios in which there is or is not a limit on the number of nodes returned by a query. We compared PMD against three baseline algorithms with three real networks, and saw large improvements vs. baseline sampling algorithms: With a budget of 2000, PMD found 15% to 170.2% more nodes than the closest baseline algorithm for the different datasets considered.
Reconsidering the Consequences of Worker Displacements: Firm versus Worker Perspective

Prior literature has established that displaced workers suffer persistent earnings losses by following workers in administrative data after mass layoffs. This literature assumes that these are involuntary separations owing to economic distress. This paper examines this assumption by matching survey data on worker-supplied reasons for separations with administrative data. Workers exhibit substantially different earnings dynamics in mass layoffs depending on the reason for separation. Using a new methodology to account for the increased separation rates across all survey responses during a mass layoff, the paper finds earnings loss estimates that are surprisingly close to those using only administrative data.
On Statistical Modeling of Sequencing Noise in High Depth Data to Assess Tumor Evolution

One cause of cancer mortality is tumor evolution to therapy-resistant disease. First line therapy often targets the dominant clone, and drug resistance can emerge from preexisting clones that gain fitness through therapy-induced natural selection. Such mutations may be identified using targeted sequencing assays by analysis of noise in high-depth data. Here, we develop a comprehensive, unbiased model for sequencing error background. We find that noise in sufficiently deep DNA sequencing data can be approximated by aggregating negative binomial distributions. Mutations with frequencies above noise may have prognostic value. We evaluate our model with simulated exponentially expanded populations as well as data from cell line and patient sample dilution experiments, demonstrating its utility in prognosticating tumor progression. Our results may have the potential to identify significant mutations that can cause recurrence. These results are relevant in the pre-treatment clinical setting to determine appropriate therapy and prepare for potential recurrence pretreatment.
Physics-Based Intrinsic Model for AlGaN/GaN HEMTs

DC and intrinsic small signal parameters are reported for AlGaN/GaN high electron mobility transistors. The calculations are based upon a self-consistent solution of Schrodinger and Poisson’s equation to model the quantum well formed in GaN. Transport parameters are obtained from an ensemble Monte Carlo simulation.
Comparator Automata in Quantitative Verification

The notion of comparison between system runs is fundamental in formal verification. This concept is implicitly present in the verification of qualitative systems, and is more pronounced in the verification of quantitative systems. In this work, we identify a novel mode of comparison in quantitative systems: the online comparison of the aggregate values of two sequences of quantitative weights. This notion is embodied by comparator automata (comparators, in short), a new class of automata that read two infinite sequences of weights synchronously and relate their aggregate values.
Energetics of Adsorbed Phenol on Ni(111) and Pt(111) by Calorimetry

The heat of adsorption and sticking probability of phenol were measured on Ni(111) at 150 K and Pt(111) at 90 K using single crystal adsorption calorimetry (SCAC). Phenol adsorbs molecularly on bot...
Cell Growth Rate Dictates the Onset of Glass to Fluidlike Transition and Long Time Superdiffusion in an Evolving Cell Colony

Numerical simulations describe cell dynamics in the early stages of tumor development and find surprising connections to soft glassy materials, providing insight that aids in understanding not just tumor growth but a host of abiotic systems evolving far from equilibrium.
Online Advertisement, Optimization and Stochastic Networks

In this paper, we propose a stochastic model to describe how search service providers charge client companies based on users' queries for the keywords related to these companies' ads by using certain advertisement assignment strategies. We formulate an optimization problem to maximize the long-term average revenue for the service provider under each client's long-term average budget constraint and design an online algorithm which captures the stochastic properties of users' queries and click-through behaviors. We solve the optimization problem by making connections to scheduling problems in wireless networks, queueing theory and stochastic networks. Unlike prior models, we do not assume that the number of query arrivals is known. Due to the stochastic nature of the arrival process considered here, either temporary “free” service, i.e., service above the specified budget (which we call “overdraft”) or under-utilization of the budget (which we call “underdraft”) is unavoidable. We prove that our online algorithm can achieve a revenue that is within O(e) of the optimal revenue while ensuring that the overdraft or underdraft is O(1/e) , where e can be arbitrarily small. With a view towards practice, we can show that one can always operate strictly under the budget. In addition, we extend our results to a click-through rate maximization model and also show how our algorithm can be modified to handle non-stationary query arrival processes and clients with short-term contracts. Our algorithm also allows us to quantify the effect of errors in click-through rate estimation on the achieved revenue. We show that we lose at most Δ/1+Δ fraction of the revenue if Δ is the relative error in click-through rate estimation. We also show that in the long run, an expected overdraft level of Ω(log(1/e)) is unavoidable (a universal lower bound) under any stationary ad assignment algorithm which achieves a long-term average revenue within O(e) of the offline optimum.