cssi/SciSciGPT-SciSciNet huggingface dataset:
Open Collaboration for Innovation: Principles and Performance

The principles of open collaboration for innovation and production, once distinctive to open source software, are now found in many other ventures. Some of these ventures are Internet based: for example, Wikipedia and online communities. Others are off-line: they are found in medicine, science, and everyday life. Such ventures have been affecting traditional firms and may represent a new organizational form. Despite the impact of such ventures, their operating principles and performance are not well understood. Here we define open collaboration OC, the underlying set of principles, and propose that it is a robust engine for innovation and production. First, we review multiple OC ventures and identify four defining principles. In all instances, participants create goods and services of economic value, they exchange and reuse each other's work, they labor purposefully with just loose coordination, and they permit anyone to contribute and consume. These principles distinguish OC from other organizational forms, such as firms or cooperatives. Next, we turn to performance. To understand the performance of OC, we develop a computational model, combining innovation theory with recent evidence on human cooperation. We identify and investigate three elements that affect performance: the cooperativeness of participants, the diversity of their needs, and the degree to which the goods are rival subtractable. Through computational experiments, we find that OC performs well even in seemingly harsh environments: when cooperators are a minority, free riders are present, diversity is lacking, or goods are rival. We conclude that OC is viable and likely to expand into new domains. The findings also inform the discussion on new organizational forms, collaborative and communal.
Power optimization in fault-tolerant topology control algorithms for wireless multi-hop networks

In ad hoc wireless networks, it is crucial to minimize power consumption while maintaining key network properties. This work studies power assignments of wireless devices that minimize power while maintaining k-fault tolerance. Specifically, we require all links established by this power setting be symmetric and form a k-vertex connected subgraph of the network graph. This problem is known to be NP-hard. We show current heuristic approaches can use arbitrarily more power than the optimal solution. Hence, we seek approximation algorithms for this problem. We present three approximation algorithms. The first algorithm gives an O(kalpha)-approximation where is the best approximation factor for the related problem in wired networks (the best alpha so far is O(log k)). With a more careful analysis, we show our second (slightly more complicated) algorithm is an O(k)-approximation. Our third algorithm assumes that the edge lengths of the network graph form a metric. In this case, we present simple and practical distributed algorithms for the cases of 2- and 3-connectivity with constant approximation factors. We generalize this algorithm to obtain an O(k2c+2)-approximation for general k-connectivity (2 les c les 4 is the power attenuation exponent). Finally, we show that these approximation algorithms compare favorably with existing heuristics. We note that all algorithms presented in this paper can be used to minimize power while maintaining -edge connectivity with guaranteed approximation factors. Recently, different set of authors used the notion of k-connectivity and the results of this paper to deal with the fault-tolerance issues for static wireless network settings.
Real-time monitoring of short-term voltage stability using PMU data

We develop a model-free approach for the short-term voltage stability monitoring of a power system. Finite time Lya-punov exponents are used as the certificate of stability. The time-series voltage data from phasor measurement units (PMU) are used to compute the Lyapunov exponent to predict voltage stability in real time. Issues related to practical implementation of the proposed method, such as phasor measurement noise, communication delay, and the finite window size for prediction, are also discussed. Furthermore, the stability certificate in the form of Lyapunov exponents is also used to determine the stability/instability contributions of the individual buses to the overall system stability and for computation of critical clearing time. Simulation results are provided for the IEEE 162-bus system to demonstrate the application of the developed method.
The Geography of Innovation Commercialization in the United States During the 1990s

This article analyzes the geographic distribution and interrelationship of three measures of innovation commercialization across the 50 largest metropolitan areas in the United States and estimates a model of the factors explaining variations in the location of innovation commercialization. Innovation commercialization tends to be highly concentrated geographically, suggesting the presence of substantial external economies in these functions. Beyond these scale effects, however, the author finds that university science and engineering capacity and local patenting activity both help to account for intercity differences in the level of innovation commercialization activity.
Thermal Analysis of Heat-Generating Pools Bounded From Below by Curved Surfaces

A computer code that features the use of a directional effective thermal conductivity in modeling natural convection in heat-generating pools has been developed to analyze heat transfer in such pools, which are bounded from below by curved surfaces. Illustrative calculations pertaining to two published experimental studies on convective heat transfer in water pools with uniformly distributed volumetric energy sources are carried out using the code. The water pools used in the two studies under consideration were cooled either from the top or from the bottom, but not from both. The utility as well as the limitations of the effective thermal conductivity approach in the context of addressing the issue of melt-pool coolability is demonstrated by comparisons of calculated results with the experimental data. 12 refs., 8 figs., 5 tabs.
A Conceptual Framework for Describing the Phenomenon of New Venture Creation

A review of the entrepreneurship literature suggests that differences among entrepreneurs and among their ventures are as great as the variation between entrepreneurs and nonentrepreneurs and between new firms and established firms. A framework for describing new venture creation integrates four major perspectives in entrepreneurship: characteristics of the individual(s) who start the venture, the organization which they create, the environment surrounding the new venture, and the process by which the new venture is started.
A Cross-National Study of Computer News Sites: Global News, Local Sites

The Internet is not only an object of and a tool for study; it is also both simultaneously global and local. In order to address how global and how local it is, this study compares the news content of 1 week from four different computer news web sites in four different countries (using four different languages). These sites use the same code base and all strive to be the same in terms of computer culture. They are global in their reach and in the news they cover, yet they are all local in terms of language and geography. They are ideal locales to study how forces of the global and the local play out on the highly connected Internet, using Google language tools for translation. Findings were surprising in that they showed very little in terms of a pattern of any sort. This is similar to a 1953 UNESCO study of newspapers, but strange in that given the passing of 50 years and the connectedness of the Internet, greater overlap was expected. Link destinations for stories that were on more than one site were also examined, and the Japanese site had more in common with the American site while the two European sites were more alike in this lens. This is also surprising, given that an East/West split was expected. Little work in this specific area was found, and this study highlights some of the questions and methodological difficulties that need to be addressed.
A new look at neutrino limits from big bang nucleosynthesis

We take a fresh look at the limits on the number of neutrino flavors derived from big bang nucleosynthesis. In particular, recent measurements of the 4 He abundance enable one to estimate the primordial 4 He mass fraction at Yp = 0.232 ± .003(stat) ± .005(syst). For a baryon to photon ratio, �, consistent with the other light elements, this leads to a best fit for the number of neutrino flavors N� < 3 (the precise number depends on �) indicating a very strong upper limit to N�. Here, we derive new upper limits on N�, paying special attention to the fact that the best estimate may lie in an unphysical region (N� < 3 if all !
Black Holes, Entropies, and Semiclassical Spacetime in Quantum Gravity

We present a coherent picture of the quantum mechanics of black holes. The picture does not require the introduction of any drastically new physical effect beyond what is already known; it arises mostly from synthesizing and (re)interpreting existing results in appropriate manners. We identify the Bekenstein-Hawking entropy as the entropy associated with coarse-graining performed to obtain semiclassical field theory from a fundamental microscopic theory of quantum gravity. This clarifies the issues around the unitary evolution, the existence of the interior spacetime, and the thermodynamic nature in black hole physics — any result in semiclassical field theory is a statement about the maximally mixed ensemble of microscopic quantum states consistent with the specified background, within the precision allowed by quantum mechanics. We present a detailed analysis of information transfer in Hawking emission and black hole mining processes, clarifying what aspects of the underlying dynamics are (not) visible in semiclassical field theory. We also discuss relations between the black hole entropy and the entanglement entropy across the horizon. We then extend our discussions to more general contexts in quantum gravity. The subjects include extensions to de Sitter and Minkowski spaces and implications for complementarity and cosmology, especially the eternally inflating multiverse.
New perspectives, extensions and applications of de Bruijn identity

This paper focuses on de Bruijn identity, a fundamental result that relates two important concepts: Fisher information and differential entropy. A novel relationship with Stein identity and extensions of de Bruijn identity are first presented. Then several applications of de Bruijn identity in deriving the Bayesian Cramer-Rao lower bound (BCRLB), Cramer-Rao lower bound (CRLB), and a new lower bound, tighter than the BCRLB, are presented. The paper concludes with an application of de Bruijn identity in designing min-max optimal training sequences for channel estimation and synchronization in the presence of unknown noise distribution.
LAG LENGTH SELECTION AND THE CONSTRUCTION OF UNIT ROOT TESTS WITH GOOD SIZE AND POWER

It is widely known that when there are errors with a moving-average root close to -1, a high order augmented autoregression is necessary for unit root tests to have good size, but that information criteria such as the AIC and the BIC tend to select a truncation lag (k) that is very small. We consider a class of Modified Information Criteria (MIC) with a penalty factor that is sample dependent. It takes into account the fact that the bias in the sum of the autoregressive coefficients is highly dependent on k and adapts to the type of deterministic components present. We use a local asymptotic framework in which the moving-average root is local to -1 to document how the MIC performs better in selecting appropriate values of k. In Monte-Carlo experiments, the MIC is found to yield huge size improvements to the DF GLS and the feasible point optimal P T test developed in Elliott, Rothenberg, and Stock (1996). We also extend the M tests developed in Perron and Ng (1996) to allow for GLS detrending of the data. The MIC along with GLS detrended data yield a set of tests with desirable size and power properties.
Unimodality and the Reflection Principle.

We show how lattice paths and the reflection principle can be used to give easy proofs of unimodality results. In particular, we give a “one-line” combinatorial proof of the unimodality of the binomial coefficients. Other examples include products of binomial coefficients, polynomials related to the Legendre polynomials, and a result connected to a conjecture of Simion.
Fast construction of hierarchical matrix representation from matrix-vector multiplication

We develop a hierarchical matrix construction algorithm using matrix-vector multiplications, based on the randomized singular value decomposition of low-rank matrices. The algorithm uses O(logn) applications of the matrix on structured random test vectors and O(nlogn) extra computational cost, where n is the dimension of the unknown matrix. Numerical examples on constructing Green's functions for elliptic operators in two dimensions show efficiency and accuracy of the proposed algorithm.
Kenya's tourist industry and global production networks: gender, race and inequality

In this article, I consider the position of gender and race in the tourism global production network in Kenya. To address a gap in scholarship on global production networks, I explore the racial and gender characteristics evident in functionally upgraded national tour operators and socially upgraded workers and community members around the Maasai Mara National Reserve. The main findings address the relation of race and gender to disarticulation practices identified in ‘societal’, ‘network’ and ‘territorial’ forms of embeddedness supported by racial and gender representations of skill capabilities and tourist desires. These practices and representations support a production network symbolized by whites, Kenyan-Asians and expatriates in the highest value segments and jobs, and indigenous African, Maasai and female workers in the lowest value positions. The findings highlight how disarticulation in economic and social upgrading is a gendered and racial process that perpetuates social difference and hierarchy.
Political polarization and the electoral effects of media bias

Abstract We develop a model in which profits of media firms depend on their audience ratings, and maximizing profits may involve catering to a partisan audience by suppressing information that the partisan audience does not like hearing. While voters are rational, understand the nature of the news suppression bias and update appropriately, important information is lost through bias and can lead to electoral mistakes. We characterize those conditions that give rise to electoral mistakes, showing that heightened political polarization and asymmetric distributions of voter ideologies make electoral mistakes more likely. Even if the median ideology is a centrist and centrist voters gain access to unbiased news, media bias can generate excessive “cross-over” voting, which, in turn, can lead to the election of the wrong candidate.
A convenient palladium-catalyzed aerobic oxidation of alcohols at room temperature

A simple Pd-catalyzed aerobic oxidation of benzylic and aliphatic alcohols to the corresponding aldehydes and ketones at room temperature is described.
A general Staudinger protocol for solution-phase parallel synthesis

Abstract The Staudinger reaction has been adapted for parallel synthesis by the application of fluorous-tethered triphenyl phosphine. The fluorous-tethered triphenylphosphine is expediently removed in parallel by Fluoro Flash ™ SPE columns to afford functionalized amines in high yields and purities.
A rapid and efficient method for the reduction of quinoxalines

Mono and di-substituted alkyl and aryl quinoxalines are rapidly reduced in high yield to their respective 1,2,3,4-tetrahydro-derivatives by borane in THF solution. In the case of the 2,3-di-substituted compounds, reduction is stereoselective yielding exclusively the cis-isomers. Sodium borohydride in acetic acid also reduces alkyl and aryl quinoxalines, but proceeds with lower yields and often produces side products. Sodium borohydride in ethanol reduces quinoxaline and 2-methylquinoxaline in high yield; however, the reaction is very slow, whereas 2,3-dialkyl and 2-aryl quinoxalines are not efficiently reduced by sodium borohydride in ethanol.
Noble gas compounds and chemistry: a brief review of interrelations and interactions with fluorine-containing species

Abstract This review is composed of six vignettes. They deal with respectively: the reaction of Xe and PtF 6 ; the reaction of O 2 and O 3 with PtF 6 ; salts of O + , the covalent OF, and noble gas-containing cations; synthesis, reactions and structure of [XeO 2 ] + en route to [XeF] + salts; [Xe 2 ] + , green and related species; neutral xenon oxides, nonmetal oxyanions, and a nonmetal fluoride “mid-valence” crisis. Interrelations and interactions are emphasized.
Effects of an Embedded Vortex on Injectant From a Single Film-Cooling Hole in a Turbulent Boundary Layer

Effects of embedded longitudinal vortices on heat transfer in turbulent boundary layers with injection from a single film cooling hole are described. These results were obtained at a freestream velocity of 10 m/s, with a film cooling hole inclined 30 degrees to horizontal and a blowing ratio of about 0.50. The ratio of vortex core diameter to injection hole diameter was 2.14, and the ratio of circulation to injection velocity times hole diameter was about 2.8. Coolant distributions and spatially resolved heat transfer measurements indicate that injection hole centerlines must be a least 2.0–2.5 vortex core diameters away from the vortex center in the lateral direction to avoid significant alterations to wall heat transfer and distributions of film coolant. Under these circumstances, protection from film cooling is evident at least up to 55 hole diameters downstream of injection. When the injection hole is closer to the vortex center, secondary flows convect most injectant into the vortex upwash and thermal protection from film cooling is destroyed for streamwise locations from the injection hole greater than 17.5 hole diameters.Copyright © 1989 by ASME
Hydrolysis-free synthesis of 3-aminocoumarins

Abstract A commonly encountered problem in the synthesis of 3-aminocoumarins is the formation of 3-hydroxycoumarins. A solution to this problem, which involves non-aqueous formation of the 3-aminocoumarin system, is described.
Synthesis of 2'-C-difluoromethylribonucleosides and their enzymatic incorporation into oligonucleotides.

Nucleosides bearing a branched ribose have significant promise as therapeutic agents and biotechnological and biochemical tools. Here we describe synthetic entry into a new subclass of these analogues, 2‘-C-β-difluoromethylribonucleosides. We constructed the glycosylating agent 4 in three steps from 1,3,5-tri-O-benzoyl-α-d-ribofuranose 1. The key steps included nucleophilic addition of difluoromethyl phenyl sulfone to 2-ketoribose 2 followed by mild and efficient reductive desulfonation. Ribofuranose 4 glycosylated bis(trimethylsilyl)uracil directly, giving difluoromethyluridine 7 efficiently after deprotection. Conversion of 4 to the corresponding ribofuranosyl bromide allowed efficient access to C, A, and G analogues. A related approach starting from methyl d-ribofuranose offered synthetic entry into the diastereomeric manifold, 2‘-C-α-difluoromethyl-arabino-α-pyrimidine. To incorporate 2‘-C-β-difluoromethyluridine into an oligodeoxynucleotide we converted 7 to the bisphosphate and carried out successiv...
Saving Queries with Randomness

In this paper, we investigate the power of randomness to save a query to an NP-complete set. We show that the PSAT ? k] ?pm-complete language randomly reduces to a language in PSAT ? k ? 1] with a one-sided error probability of 1/?k/2? or a two sided-error probability of 1/(k+1). Furthermore, we prove that these probability bounds are tight; i.e., they cannot be improved by 1/poly, unless PH collapses. We also obtain tight performance bounds for randomized reductions between nearby classes in the Boolean and bounded query hierarchies. These bounds provide probability thresholds for completeness under randomized reductions in these classes. Using these thresholds, we show that certain languages in the Boolean hierarchy which are not ?pm-complete in some relativized worlds, nevertheless inherit many of the hardness properties associated with the ?pm-complete languages. Finally, we explore the relationship between randomization and functions that are computable using bounded queries to SAT. For any function h(n) = O(log n), we show that there is a function f computable using h(n) nonadaptive queries to SAT, which cannot be computed correctly with probability 1/2 + 1/poly by any randomized machine which makes less than h(n) adaptive queries to any oracle, unless PH collapses.
Orofacial Injuries as Markers for Intimate Partner Violence

Intimate partner violence (IPV) is physical or sexual violence made by 1 partner to another and is a prevalent and serious health risk, particularly for women. It is estimated that more than 2.5 million women are abused annually and 30% to 50% of all female homicides were perpetrated by former or current intimate partners. Beyond the physical and psychological repercussions, abuse victims have lower health-related quality of life and higher use of health services. A growing awareness f the scope and effects of IPV have led various health care bodies including the merican Medical Association and the American College of Obstetricians and ynecologists to recommend that all female patients be asked routinely about abuse, egardless of their presenting injury or symptoms. These recommendations are based on available evidence about the burden of IPV and the benefits of provider referral for help. Early recognition and diagnosis of IPV and appropriate referral may lead to early intervention to prevent future injuries. However, there are no obvious linical characteristics to aid in the diagnosis of IPV. Current clinical standards for identifying IPV-related injury is patient self-report hrough either a spontaneous or a prompted disclosure. Other studies have uggested useful, but ambiguous, criteria for identifying victims of IPV seen in the mergency department and outpatient clinical setting. When interviewed, only % to 6% of women report being assaulted by their intimate sexual partners. hereas trauma to the head, face, shoulders, breast, abdomen or extremities is ften documented, the victim’s report of injury is frequently incompatible or nconsistent with the mechanism or location of injury. –10 Facial injuries account for a significant proportion of emergency department visits, yet, few reports specify the causes or patterns of orofacial injuries in victims with IPV-related injuries.
Discretion in Hiring

Job testing technologies enable firms to rely less on human judgement when making hiring decisions. Placing more weight on test scores may improve hiring decisions by reducing the influence of human bias or mistakes but may also lead firms to forgo the potentially valuable private information of their managers. We study the introduction of job testing across 15 firms employing low-skilled service sector workers. When faced with similar applicant pools, we find that managers who appear to hire against test recommendations end up with worse average hires. This suggests that managers often overrule test recommendations because they are biased or mistaken, not because they have superior private information. The firms in our setting may therefore be able to improve outcomes of hires by limiting managerial discretion and relying more on test recommendations.
Supervised learning for dynamical system learning

Recently there has been substantial interest in spectral methods for learning dynamical systems. These methods are popular since they often offer a good tradeoff between computational and statistical efficiency. Unfortunately, they can be difficult to use and extend in practice: e.g., they can make it difficult to incorporate prior information such as sparsity or structure. To address this problem, we present a new view of dynamical system learning: we show how to learn dynamical systems by solving a sequence of ordinary supervised learning problems, thereby allowing users to incorporate prior knowledge via standard techniques such as L1 regularization. Many existing spectral methods are special cases of this new framework, using linear regression as the supervised learner. We demonstrate the effectiveness of our framework by showing examples where nonlinear regression or lasso let us learn better state representations than plain linear regression does; the correctness of these instances follows directly from our general analysis.
Energy Flows in Low-Entropy Complex Systems

Nature’s many complex systems—physical, biological, and cultural—are islands of low-entropy order within increasingly disordered seas of surrounding, high-entropy chaos. Energy is a principal facilitator of the rising complexity of all such systems in the expanding Universe, including galaxies, stars, planets, life, society, and machines. A large amount of empirical evidence—relating neither entropy nor information, rather energy—suggests that an underlying simplicity guides the emergence and growth of complexity among many known, highly varied systems in the 14-billion-year-old Universe, from big bang to humankind. Energy flows are as centrally important to life and society as they are to stars and galaxies. In particular, the quantity energy rate density—the rate of energy flow per unit mass—can be used to explicate in a consistent, uniform, and unifying way a huge collection of diverse complex systems observed throughout Nature. Operationally, those systems able to utilize optimal amounts of energy tend to survive and those that cannot are non-randomly eliminated.
Reduced skeletal muscle function is associated with decreased fiber cross-sectional area in the Cy/+ rat model of progressive kidney disease

Background The combination of skeletal muscle wasting and compromised function plays a role in the health decline commonly observed in chronic kidney disease (CKD) patients, but the pathophysiology of muscle mass/strength changes remains unclear. The purpose of this study was to characterize muscle properties in the Cy/+ rat model of spontaneously progressive CKD. Methods Leg muscle function and serum biochemistry of male Cy/+ (CKD) rats and their nonaffected littermates (NLs) were assessed in vivo at 25, 30 and 35 weeks of age. Architecture and histology of extensor digitorum longus (EDL) and soleus (SOL) muscles were assessed ex vivo at the conclusion of the experiment. We tested the hypothesis that animals with CKD have progressive loss of muscle function, and that this functional deficit is associated with loss of muscle mass and quality. Results Thirty-five-week-old CKD rats produced significantly lower maximum torque in ankle dorsiflexion and shorter time to maximum torque, and longer half relaxation time in dorsiflexion and plantarflexion compared with NL rats. Peak dorsiflexion torque (but not plantarflexion torque) in CKD remained steady from 25 to 35 weeks, while in NL rats, peak torque increased. Mass, physiologic cross-sectional area (CSA) and fiber-type (myosin heavy chain isoform) proportions of EDL and SOL were not different between CKD and NL. However, the EDL of CKD rats showed reduced CSAs in all fiber types, while only MyHC-1 fibers were decreased in area in the SOL. Conclusions The results of this study demonstrate that muscle function progressively declines in the Cy/+ rat model of CKD. Because whole muscle mass and architecture do not vary between CKD and NL, but CKD muscles show reduction in individual fiber CSA, our data suggest that the functional decline is related to increased muscle fiber atrophy.
Stereoselective synthesis of spirooxindole derivatives using an organocatalyzed tandem Michael-Michael reaction

A highly efficient stereoselective method for the synthesis of functionalized spirooxindole derivatives with three stereogenic centers was realized through an organocatalytic tandem Michael-Michael reaction. By employing (S)-α,α-diphenylprolinol trimethylsilyl ether as the catalyst and N,N'-bis[3,5-bis(trifluoromethyl)phenyl]thiourea as the cocatalyst, the reaction between N-tritylisatylidenemalononitriles and (E)-7-alkyl-7-oxohept-5-enals yields the desired spirooxindole products in good yields (76-95%) and with excellent diastereoselectivities (up to 97 : 3 dr) and enantioselectivities (up to 98% ee), which can be stereoselectively converted into the spiro[indoline-3,8'-isoquinoline] derivative through an intramolecular reductive amination reaction.
Self-Help in the Break-Up of Informal Partnerships

This paper rationalizes and harmonizes cases in which business partners attempt to expel one of their number.
Sparse Hierarchical Tucker Factorization and Its Application to Healthcare

We propose a new tensor factorization method, called the Sparse Hierarchical-Tucker (Sparse H-Tucker), for sparse and high-order data tensors. Sparse H-Tucker is inspired by its namesake, the classical Hierarchical Tucker method, which aims to compute a tree-structured factorization of an input data set that may be readily interpreted by a domain expert. However, Sparse H-Tucker uses a nested sampling technique to overcome a key scalability problem in Hierarchical Tucker, which is the creation of an unwieldy intermediate dense core tensor, the result of our approach is a faster, more space-efficient, and more accurate method. We test our method on a real healthcare dataset, which is collected from 30K patients and results in an 18th order sparse data tensor. Unlike competing methods, Sparse H-Tucker can analyze the full data set on a single multi-threaded machine. It can also do so more accurately and in less time than the state-of-the-art: on a 12th order subset of the input data, Sparse H-Tucker is 18x more accurate and 7.5x faster than a previously state-of-the-art method. Moreover, we observe that Sparse H-Tucker scales nearly linearly in the number of non-zero tensor elements. The resulting model also provides an interpretable disease hierarchy, which is confirmed by a clinical expert.
CFD SIMULATION OF PHASE DISTRIBUTION IN ADIABATIC UPWARD BUBBLY FLOWS USING INTERFACIAL AREA TRANSPORT EQUATION

In the study of gas-liquid two-phase flows, one challenge is to describe the dynamic changes in flow structure, which can be considerably affected by bubble coalescence and/or disintegration in addition to bubble nucleation and condensation processes. The interfacial structure, to a first-order approximation, may be characterized by the void fraction and a geometric parameter named "interfacial area concentration, " the evolution of which can be modeled by an interfacial area transport equation (IATE). A one-group IATE has been developed for bubbly flows in the literature, accounting for three dominant mechanisms: coalescence of bubbles due to random bubble collisions driven by turbulence, coalescence of bubbles due to wake entrainment, and disintegration of bubbles caused by turbulent-eddy impact. The current study is aimed at examining the capability of a computational fluid dynamics code, namely, FLUENT, with the one-group IATE implemented, in predicting two-phase-flow phase distributions. Simulations using the Eulerian multiphase model in FLUENT 6.2.16 have been performed for adiabatic upward bubbly flows in a pipe of 50.8-mm inner diameter with a range of void fractions from 4.9 to 23.1%. The predicted phase distributions yield satisfactory agreement with available experimental data, demonstrating that FLUENT with the IATE can provide a valuable simulation tool for two-phase bubbly flows.
Social Metaphor Detection via Topical Analysis

With the massive amount of social media data becoming available, there is a rising interest in automatic metaphor detection and interpretation from open social text. One of the most well-known approaches to this subject is identifying the violation of selectional preference. The basic concept of selectional preference is that verbs tend to have semantic preferences of their arguments and that violations of these preferences are strong indicators of metaphorical language use. Nevertheless, previously, few works have focused on metaphor detection of social media data. In response to this problem, we propose a three-step framework that is based on the technology of selection preference modeling to detect metaphors in social media data. We conduct a pilot study of this framework on the data of a real-world online support group. Furthermore, to improve our approach, we also leverage topical analysis techniques in our framework. As a result, we address the challenges of the task of metaphor detection in social media data, provide qualitative analysis for our experiments, and illustrate our insight based on the results.
Bayesian inference for a flexible class of bivariate beta distributions

ABSTRACTSeveral bivariate beta distributions have been proposed in the literature. In particular, Olkin and Liu [A bivariate beta distribution. Statist Probab Lett. 2003;62(4):407–412] proposed a 3 parameter bivariate beta model which Arnold and Ng [Flexible bivariate beta distributions. J Multivariate Anal. 2011;102(8):1194–1202] extend to 5 and 8 parameter models. The 3 parameter model allows for only positive correlation, while the latter models can accommodate both positive and negative correlation. However, these come at the expense of a density that is mathematically intractable. The focus of this research is on Bayesian estimation for the 5 and 8 parameter models. Since the likelihood does not exist in closed form, we apply approximate Bayesian computation, a likelihood free approach. Simulation studies have been carried out for the 5 and 8 parameter cases under various priors and tolerance levels. We apply the 5 parameter model to a real data set by allowing the model to serve as a prior to correl...
Weak harmonic Maass forms of weight 5/2 and a mock modular form for the partition function

We construct a natural basis for the space of weak harmonic Maass forms of weight 5/2 on the full modular group. The nonholomorphic part of the first element of this basis encodes the values of the ordinary partition function p(n). We obtain a formula for the coefficients of the mock modular forms of weight 5/2 in terms of regularized inner products of weakly holomorphic modular forms of weight −1/2, and we obtain Hecke-type relations among these mock modular forms.
Route to α-Aryl Phosphonoacetates: Useful Synthetic Precursors in the Horner–Wadsworth–Emmons Olefination

A versatile and general catalytic strategy has been developed for the α-arylation of phosphonoacetates utilizing parallel microscale experimentation. These α-substituted phosphonoacetates are widely useful, notably as substrates in the Horner–Wadsworth–Emmons-type olefinations. However, the current routes to these products involve harsh conditions, limiting the variety of functionality. The reported method can be used with a variety of aryl chlorides and aryl bromides, including several heterocyclic examples.
Firearm violence and effects on concealed gun carrying: large debate and small effects

Research has yet to identify a predictive relationship between crime and the issuance of aggregated concealed gun permits. The present study examines if a macro-level relationship exists between both concealed carry firearm applications and permits and violent crime committed with a firearm. Florida county-level data for concealed carry applications and violent crime are combined with police employment, socioeconomic, political, and firearm subculture variables across two temporal periods using both county and year fixed effects models. Unstandardized negative binomial regressions are employed with multiple alternative model specifications and diagnostic tests. Findings indicate a positive association between crime, especially those committed with a firearm, and concealed carry applications and permits. The effect size of firearm violent crime on concealed carry applications and permits is minimal. There is a demonstrable link between firearm violence and concealed carry applications and permits issued, n...
An Inverse Demand System for Blue Crab in the Chesapeake Bay: Endogeneity and Seasonality

Abstract This paper studies the demand structure of the blue crab market in the Chesapeake Bay. In addition to providing empirical results regarding the economically important fishery, the paper offers a useful example of the potential for inverse demand system estimations for seafood where quantities are often defined prior to prices, and a variety of products are obtained from a single system. This is done with a nonlinear Inverse Almost Ideal Demand System coupled with seasonal patterns and controlling for endogeneity. The model used in this paper is able to address seasonality in demand in terms of varying flexibilities over seasons and deals with endogeneity in accordance with biological stock assessment data. Empirical results show significant season-varying market behaviors. The results also indicate the presence of endogeneity in the demand system. The flexibilities are calculated according to the estimates before and after controlling for endogeneity. Most market categories are price inflexible across seasons. The #1 Male, #2 Male, Female, and Mixed categories are necessities, while the Soft and Peeler category is a luxuary. Cross-category flexibilities suggest that most categories are quantity substitutes.
A contraction approach to input tracking via high gain feedback

This paper adopts a contraction approach to study exogenous input tracking in dynamical systems under high gain proportional output feedback. We give conditions under which contraction of a nonlinear system's tracking error implies input to output stability from the input signal's time derivatives to the tracking error. This result is then used to demonstrate that the negative feedback connection of plants composed of two strictly positive real subsystems in cascade can follow external inputs with tracking errors that can be made arbitrarily small by applying a sufficiently large feedback gain. We utilize this result to design a biomolecular feedback regulation scheme for a synthetic genetic sensor model, making it robust to variations in the availability of a cellular resource required for protein production.
Coherent cavity-enhanced dual-comb spectroscopy.

Dual-comb spectroscopy allows for the rapid, multiplexed acquisition of high-resolution spectra without the need for moving parts or low-resolution dispersive optics. This method of broadband spectroscopy is most often accomplished via tight phase locking of two mode-locked lasers or via sophisticated signal processing algorithms, and therefore, long integration times of phase coherent signals are difficult to achieve. Here we demonstrate an alternative approach to dual-comb spectroscopy using two phase modulator combs originating from a single continuous-wave laser capable of > 2 hours of coherent real-time averaging. The dual combs were generated by driving the phase modulators with step-recovery diodes where each comb consisted of > 250 teeth with 203 MHz spacing and spanned > 50 GHz region in the near-infrared. The step-recovery diodes are passive devices that provide low-phase-noise harmonics for efficient coupling into an enhancement cavity at picowatt optical powers. With this approach, we demonstrate the sensitivity to simultaneously monitor ambient levels of CO2, CO, HDO, and H2O in a single spectral region at a maximum acquisition rate of 150 kHz. Robust, compact, low-cost and widely tunable dual-comb systems could enable a network of distributed multiplexed optical sensors.
Modeling silica aerogel optical performance by determining its radiative properties

Silica aerogel has been known as a promising candidate for high performance transparent insulation material (TIM). Optical transparency is a crucial metric for silica aerogels in many solar related applications. Both scattering and absorption can reduce the amount of light transmitted through an aerogel slab. Due to multiple scattering, the transmittance deviates from the Beer-Lambert law (exponential attenuation). To better understand its optical performance, we decoupled and quantified the extinction contributions of absorption and scattering separately by identifying two sets of radiative properties. The radiative properties are deduced from the measured total transmittance and reflectance spectra (from 250 nm to 2500 nm) of synthesized aerogel samples by solving the inverse problem of the 1-D Radiative Transfer Equation (RTE). The obtained radiative properties are found to be independent of the sample geometry and can be considered intrinsic material properties, which originate from the aerogel’s microstructure. This finding allows for these properties to be directly compared between different samples. We also demonstrate that by using the obtained radiative properties, we can model the photon transport in aerogels of arbitrary shapes, where an analytical solution is difficult to obtain.
A deterministic alternative to the full configuration interaction quantum Monte Carlo method

Development of exponentially scaling methods has seen great progress in tackling larger systems than previously thought possible. One such technique, full configuration interaction quantum Monte Carlo, is a useful algorithm that allows exact diagonalization through stochastically sampling determinants. The method derives its utility from the information in the matrix elements of the Hamiltonian, along with a stochastic projected wave function, to find the important parts of Hilbert space. However, the stochastic representation of the wave function is not required to search Hilbert space efficiently, and here we describe a highly efficient deterministic method that can achieve chemical accuracy for a wide range of systems, including the difficult Cr2 molecule. We demonstrate for systems like Cr2 that such calculations can be performed in just a few cpu hours which makes it one of the most efficient and accurate methods that can attain chemical accuracy for strongly correlated systems. In addition our method also allows efficient calculation of excited state energies, which we illustrate with benchmark results for the excited states of C2.
Early Th1 immunity promotes immune tolerance and may impair graft-versus-leukemia effect after allogeneic hematopoietic cell transplantation.

Acute graft-versus-host disease (aGvHD) is an unpredictable immunological complication that affects the skin, gut, or liver following allogeneic hematopoietic cell transplantation (HCT). Donor Th1 cells can initiate aGvHD after recognition of recipient alloantigens and migration to target tissues via homing receptors.1 Paradoxically, experiments in animal models of transplantation suggest that deficiency of the inflammatory Th1 cytokine IFN-γ can exacerbate aGvHD severity and mortality.2,3 Investigators have interpreted these results to mean that other cell types are capable of generating aGvHD or that loss of a protective function related to IFN-γ was responsible for the intensified alloreactivity observed in these animal models.
Borrowing Constraints, College Enrollment, and Delayed Entry

In this article, I propose and estimate a dynamic model of education, borrowing, and work decisions of high school graduates. I examine the effect of relaxing borrowing constraints on educational attainment by simulating increases in the amount students are permitted to borrow from government-sponsored loan programs. My results indicate that borrowing constraints have a small impact on attainment: the removal of education-related borrowing constraints raises bachelor’s degree completion by 2.4 percentage points. Tuition subsidies are necessary to obtain larger increases: I find that higher subsidies for average-ability students are the most cost effective targeted tuition subsidies.
MR Imaging of Lumbar Arachnoiditis

To assess the usefulness of MR in defining the changes of lumbar arachnoiditis, we reviewed retrospectively the MR, plain-film myelographic, and CT myelographic findings in 100 patients referred for evaluation of failed-back-surgery syndrome. In 11 of 12 cases of arachnoiditis demonstrated by plain-film and CT myelography, an abnormal configuration of nerve roots was seen by MR. The correlated MR and CT and plain-film myelographic changes were divided into three anatomic groups: group 1 showed conglomerations of adherent roots residing centrally within the thecal sac, group 2 demonstrated roots adherent peripherally to the meninges giving rise to an “empty-sac” appearance, and group 3 demonstrated a soft-tissue mass replacing the subarachnoid space. There was one false-negative MR study. For the diagnosis of moderate to severe arachnoiditis, we found MR to correlate excellently with CT myelographic and plain-film myelographic findings.
A model of two-destination choice in trip chains with GPS data

Abstract Studying trip chaining behavior has been a challenging endeavor which requires the support of microscopic travel data. New insights into trip chaining can be gained from real-time GPS travel data. This research introduces a framework that considers two-destination choice in the context of home-based trip chains. We propose and empirically compare three alternatives of building choice sets where we consider various relationships of the two destinations (such as major–minor destinations, selecting one first, and selecting two concurrently). Our choice set formation alternatives use survival models to determine the selection probability of a destination. Our results reveal that trip chaining behavior is shaped by the features of retail clusters, spatial patterns of clusters, transportation networks, and the axis of travel. This research reveals that not only the spatial relationship but also the land use relationship of the destinations in a trip chain affect the decision making process.
Forensic Psychiatry and Forensic Psychology: Forensic Psychology – Education, Training, and Certification

A review of the history of training models in forensic psychology is followed by a discussion of key education, training, and certification problems. Issues considered include: rivalry with forensic psychiatry; ethical standards of practice; advanced certification; vanity boards; current professional organizations; and resources for graduate education.
Longitudinal Relaxation of a Thermally Stressed Fiber by Prismatic Dislocation Punching

A model predicting the number of prismatic loops dislocation punched at the ends of a cylindrical fiber by thermal mismatch stresses is presented and compared to another based on a mismatching ellipsoid. The longitudinal stress in the fiber and the interfacial shear stress are derived by adapting a shear-lag model to the plastic portion of the interface. In certain cases, the central part of the fiber is strained by plastic and elastic interfacial shear until it exhibits no mismatch with the matrix. This leads to a critical fiber length above which the number of punched loops is constant.
Modified Schottky Barrier Heights by Interfacial Doped Layers: MBE Al on GaAs

Modifications to the Schottky barrier heights of Al: GaAs diodes were achieved through the use of heavily doped semiconductor interfacial layers. These contacts were grown entirely in an ultra-high vacuum molecular beam epitaxy system, allowing the preparation of nearly ideal metal: semiconductor structures. We used p+-GaAs layers (NA=1018-1020 cm-3, tp=50–360 A) at Al: n-GaAs interfaces (ND=5×1016 cm-3) to reproducibly increase the barrier height from 0.79 eV to 1.24 eV, with minimal degradation of the diode ideality factor (n=1.03–1.21). Our modeling of these diodes utilized the results of the unified defect model for surface and interface states on III-V compound semiconductors. The results of current-voltage and capacitance-voltage measurements on these diodes are compared with theory.