cssi/SciSciGPT-SciSciNet huggingface dataset:
Formalizing Cyber–Physical System Model Transformation Via Abstract Interpretation

Model transformation tools assist system designers by reducing the labor--intensive task of creating and updating models of various aspects of systems, ensuring that modeling assumptions remain consistent across every model of a system, and identifying constraints on system design imposed by these modeling assumptions. We have proposed a model transformation approach based on abstract interpretation, a static program analysis technique. Abstract interpretation allows us to define transformations that are provably correct and specific. This work develops the foundations of this approach to model transformation. We define model transformation in terms of abstract interpretation and prove the soundness of our approach. Furthermore, we develop formalisms useful for encoding model properties. This work provides a methodology for relating models of different aspects of a system and for applying modeling techniques from one system domain, such as smart power grids, to other domains, such as water distribution networks.
Humans can decipher adversarial images.

Does the human mind resemble the machine-learning systems that mirror its performance? Convolutional neural networks (CNNs) have achieved human-level benchmarks in classifying novel images. These advances support technologies such as autonomous vehicles and machine diagnosis; but beyond this, they serve as candidate models for human vision itself. However, unlike humans, CNNs are “fooled” by adversarial examples—nonsense patterns that machines recognize as familiar objects, or seemingly irrelevant image perturbations that nevertheless alter the machine’s classification. Such bizarre behaviors challenge the promise of these new advances; but do human and machine judgments fundamentally diverge? Here, we show that human and machine classification of adversarial images are robustly related: In 8 experiments on 5 prominent and diverse adversarial imagesets, human subjects correctly anticipated the machine’s preferred label over relevant foils—even for images described as “totally unrecognizable to human eyes”. Human intuition may be a surprisingly reliable guide to machine (mis)classification—with consequences for minds and machines alike. Convolutional Neural Networks (CNNs) have reached human-level benchmarks in classifying images, but they can be “fooled” by adversarial examples that elicit bizarre misclassifications from machines. Here, the authors show how humans can anticipate which objects CNNs will see in adversarial images.
Dynamic Multisourcing with Dependent Supplies

As multisourcing becomes a widely adopted strategy in dynamic procurement planning, firms inevitably source from suppliers with dependent material flows, and such supply dependence, created by comm...
Assimilation of Satellite Soil Moisture for Improved Atmospheric Reanalyses

AbstractA newly developed, weakly coupled land and atmosphere data assimilation system for NASA’s Global Earth Observing System model is presented, and used to demonstrate the benefit of assimilati...
Markov Chains With Maximum Return Time Entropy for Robotic Surveillance

Motivated by robotic surveillance applications, this paper studies the novel problem of maximizing the return time entropy of a Markov chain, subject to a graph topology with travel times and stationary distribution. The return time entropy is the weighted average, over all graph nodes, of the entropy of the first return times of the Markov chain; this objective function is a function series that does not admit, in general, a closed form. This paper features theoretical and computational contributions. First, we obtain a discrete-time delayed linear system for the return time probability distribution and establish its convergence properties. We show that the objective function is continuous over a compact set and therefore admits a global maximum. We then establish upper and lower bounds between the return time entropy and the well-known entropy rate of the Markov chain. To compute the optimal Markov chain numerically, we establish the asymptotic equality between entropy, conditional entropy, and truncated entropy, and propose an iteration to compute the gradient of the truncated entropy. Finally, we apply these results to the robotic surveillance problem. Our numerical results show that for a model of rational intruder over prototypical graph topologies and test cases, the maximum return time entropy Markov chain outperforms several pre-existing Markov chains.
Reliance on science: Worldwide front-page patent citations to scientific articles

Research summary To what extent do firms rely on basic science in their R&D efforts? Several scholars have sought to answer this and related questions, but progress has been impeded by the difficulty of matching unstructured references in patents to published papers. We introduce an open‐access dataset of references from the front pages of patents granted worldwide to scientific papers published since 1800. Each patent‐paper linkage is assigned a confidence score, which is characterized in a random sample by false negatives versus false positives. All matches are available for download at http://relianceonscience.org. We outline several avenues for strategy research enabled by these new data. Managerial summary To what extent do firms rely on basic science in their R&D efforts? Several scholars have sought to answer this and related questions, but progress has been impeded by the difficulty of matching unstructured references in patents to published papers. We introduce an open‐access dataset of references from the front pages of patents granted worldwide to scientific papers published since 1800. Each patent‐paper linkage is assigned a confidence score, and we check a random sample of these confidence scores by hand in order to estimate both coverage (i.e., of the matches we should have found, what percentage did we find) and accuracy (i.e., of the matches we found, what percentage are correct). We outline several avenues for strategy research enabled by these new data.
Who Studies International Law? Explaining Cross-national Variation in Compulsory International Legal Education

The compulsory study of international law is a universal component of legal education in some states, but extremely uncommon or nonexistent in others. This article uses global data and statistical methods to test a number of conceivable explanations for this puzzling feature of international society. In contrast to much of the empirical literature on state behavior in relation to international law, we find that functionalist and sociopolitical variables carry little explanatory power, and that historical variables — specifically, legal tradition and regional geography — instead account for the overwhelming majority of the global pattern. We explore potential explanations for these findings and discuss implications for scholars, legal educators, and policymakers.
Generation of arbitrary all-photonic graph states from quantum emitters

We present protocols to generate arbitrary photonic graph states from quantum emitters that are in principle deterministic. We focus primarily on two-dimensional cluster states of arbitrary size due to their importance for measurement-based quantum computing. Our protocols for these and many other types of two-dimensional graph states require a linear array of emitters in which each emitter can be controllably pumped, rotated about certain axes, and entangled with its nearest neighbors. We show that an error on one emitter produces a localized region of errors in the resulting graph state, where the size of the region is determined by the coordination number of the graph. We describe how these protocols can be implemented for different types of emitters, including trapped ions, quantum dots, and nitrogen-vacancy centers in diamond.
IMHO Fine-Tuning Improves Claim Detection

Claims are the central component of an argument. Detecting claims across different domains or data sets can often be challenging due to their varying conceptualization. We propose to alleviate this problem by fine-tuning a language model using a Reddit corpus of 5.5 million opinionated claims. These claims are self-labeled by their authors using the internet acronyms IMO/IMHO (in my (humble) opinion). Empirical results show that using this approach improves the state of art performance across four benchmark argumentation data sets by an average of 4 absolute F1 points in claim detection. As these data sets include diverse domains such as social media and student essays this improvement demonstrates the robustness of fine-tuning on this novel corpus.
Stabilization policy, infrastructure investment, and welfare in a small open economy

Abstract Using a two-sector neoclassical growth model in an open economy setting with heterogeneous agents, this paper studies the distributional effects and welfare implications of a joint monetary and fiscal policy response to public infrastructure expansion in emerging market economies. The results show that fiscal stabilization policy is critical for achieving fiscal sustainability and price stability. With joint support of monetary and fiscal policy, government infrastructure investment provides significant welfare gains to the economy, and the choice of fiscal instruments has major distributional effects across agents: saving households accrue the highest welfare gains with new bond issuance, while hand-to-mouth consumers are better off when non-distorting taxes are adjusted. These potential tradeoffs in welfare due to households’ differing responses to infrastructure expansion have important implications for policy making.
Benzotriazole-Assisted Aromatic Ring Annulation: Efficient and General Syntheses of Polysubstituted Naphthalenes and Phenanthrenes.

(Benzotriazol-1-ylmethyl)benzenes and -naphthalenes 1a−f, easily accessible from benzyl bromides and benzotriazole, readily undergo lithiation and subsequent 1,4-addition to α,β-unsaturated aldehyd...
Siloxanes as temporary tethers in [2+2] photocycloadditions

Abstract Intramolecular [2+2] photocycloadditions utilizing siloxanes as temporary tethers between an enone and olefin results in the products of an intermolecular photocycloaddition with the selectivity of the intramolecular reaction after cleavage of the temporary tether.
Asymmetric Synthesis of Homoallylic Amines and Functionalized Pyrrolidines via Direct Amino-Crotylation of In Situ Generated Imines

Abstract The asymmetric synthesis of functionalized homoallylic amines and silyl functionalized pyrrolidines through the Lewis acid promoted condensation of chiral (E)-crotylsilanes with sulfonyl imines and in situ generated N-acyl imines is described. We had anticipated that this bond construction could be used in the asymmetric synthesis of the N-terminal amino acid subunit of the nikkomycins. Aryl sulfonyl imines condense with chiral silane reagents in the presence of BF3·OEt2 to form homoallylic arylsulfonyl amines with useful levels of syn selectivity. For cases involving aryl N-acyl imines we have learned that the temperature controls the course of the reaction. For instance, at temperatures of −78°C or below the major product is the pyrrolidine, while at higher temperatures (−30 to −20°C) the homoallylic amine is produced. For the cases studied, the [3+2]-annulation is limited to aryl imine derivatives, as alkyl- and branched- imines failed to produce the pyrrolidine derivatives: higher reaction temperatures promote the conversion of the annulation product to the homoallylic amines. In double stereodifferentiating reactions with in situ generated imines, good levels of selectivity were achieved in the formation of secondary amines bearing syn–anti and syn–syn stereochemical triads.
AN EXPEDITIOUS ONE POT SYNTHESIS OF DIBENZO[a,g]FLUORENE

A convenient one-pot synthesis of dibenzo[a,g]fluorene via enolate alkylation and cyclodehydration-aromatisation route has been developed.
Kinetic Resolution of Racemic Lactones by Conjugate Additions of Allylic Organolithium Species: Direct Formation of Three Contiguous Centers with High Diastereo- and Enantioselectivities

Kinetic resolution of racemic α,β-unsaturated lactones by the organolithium species produced from asymmetric lithiation of N-Boc-N-(p-methoxyphenyl)cinnamylamine provides conjugate addition products with three contiguous stereogenic centers in yields of 62−77% with diastereomeric ratios from 75:25 to >99:1 and enantiomeric ratios for the major diastereomers from 94:6 to 98:2.
The asymmetric synthesis of (2S,3R)-capreomycidine

Abstract An improved asymmetric synthesis of the guanidine-containing amino acid (2 S ,3 R )-capreomycidine has been achieved in seven steps and 28% overall yield. The key synthetic step involved a Mannich-type reaction between a chiral glycine aluminum enolate and the benzyl-imine of 3- tert -butyldimethylsiloxy-propionaldehyde.
Wisdom of artificial crowds feature selection in untargeted metabolomics: An application to the development of a blood-based diagnostic test for thrombotic myocardial infarction.

Abstract Introduction Heart disease remains a leading cause of global mortality. While acute myocardial infarction (colloquially: heart attack), has multiple proximate causes, proximate etiology cannot be determined by a blood-based diagnostic test. We enrolled a suitable patient cohort and conducted a non-targeted quantification of plasma metabolites by mass spectrometry for developing a test that can differentiate between thrombotic MI, non-thrombotic MI, and stable disease. A significant challenge in developing such a diagnostic test is solving the NP-hard problem of feature selection for constructing an optimal statistical classifier. Objective We employed a Wisdom of Artificial Crowds (WoAC) strategy for solving the feature selection problem and evaluated the accuracy and parsimony of downstream classifiers in comparison with traditional feature selection techniques including the Lasso and selection using Random Forest variable importance criteria. Materials and methods Artificial Crowd Wisdom was generated via aggregation of the best solutions from independent and diverse genetic algorithm populations that were initialized with bootstrapping and a random subspaces constraint. Results/Conclusions Strong evidence was observed that a statistical classifier utilizing WoAC feature selection can discriminate between human subjects presenting with thrombotic MI, non-thrombotic MI, and stable Coronary Artery Disease given abundances of selected plasma metabolites. Utilizing the abundances of twenty selected metabolites, a leave-one-out cross-validation estimated misclassification rate of 2.6% was observed. However, the WoAC feature selection strategy did not perform better than the Lasso over the current study.
Network Enhancement: a general method to denoise weighted biological networks

Networks are ubiquitous in biology where they encode connectivity patterns at all scales of organization, from molecular to the biome. However, biological networks are noisy due to the limitations of the technology used to generate them as well as inherent variation within samples. The presence of high levels of noise can hamper discovery of patterns and dynamics encapsulated by these networks. Here we propose Network Enhancement (NE), a novel method for improving the signal-to-noise ratio of undirected, weighted networks, and thereby improving the performance of downstream analysis. NE applies a novel operator that induces sparsity and leverages higher-order network structures to remove weak edges and enhance real connections. This iterative approach has a closed-form solution at convergence with desirable performance properties. We demonstrate the effectiveness of NE in denoising biological networks for several challenging yet important problems. Our experiments show that NE improves gene function prediction by denoising interaction networks from 22 human tissues. Further, we use NE to interpret noisy Hi-C contact maps from the human genome and demonstrate its utility across varying degrees of data quality. Finally, when applied to fine-grained species identification, NE outperforms alternative approaches by a significant margin. Taken together, our results indicate that NE is widely applicable for denoising weighted biological networks, especially when they contain high levels of noise.
Sequential Anomaly Detection using Inverse Reinforcement Learning

One of the most interesting application scenarios in anomaly detection is when sequential data are targeted. For example, in a safety-critical environment, it is crucial to have an automatic detection system to screen the streaming data gathered by monitoring sensors and to report abnormal observations if detected in real-time. Oftentimes, stakes are much higher when these potential anomalies are intentional or goal-oriented. We propose an end-to-end framework for sequential anomaly detection using inverse reinforcement learning (IRL), whose objective is to determine the decision-making agent's underlying function which triggers his/her behavior. The proposed method takes the sequence of actions of a target agent (and possibly other meta information) as input. The agent's normal behavior is then understood by the reward function which is inferred via IRL. We use a neural network to represent a reward function. Using a learned reward function, we evaluate whether a new observation from the target agent follows a normal pattern. In order to construct a reliable anomaly detection method and take into consideration the confidence of the predicted anomaly score, we adopt a Bayesian approach for IRL. The empirical study on publicly available real-world data shows that our proposed method is effective in identifying anomalies.
Microwave-assisted solvent-free parallel synthesis of thioamides

Abstract Rapid parallel synthesis of thioamides is described. A library of amides, synthesised by mixing acyl chlorides and diamines, was transformed into the corresponding thioamides utilising Lawesson's reagent as the oxygen/sulphur exchange reagent. Purification by solid-phase extraction afforded the library members in adequate purities and yields.
Sensations from a single M-cone depend on the activity of surrounding S-cones

Color vision requires the activity of cone photoreceptors to be compared in post-receptoral circuitry. Decades of psychophysical measurements have quantified the nature of these comparative interactions on a coarse scale. How such findings generalize to a cellular scale remains unclear. To answer that question, we quantified the influence of surrounding light on the appearance of spots targeted to individual cones. The eye's aberrations were corrected with adaptive optics and retinal position was precisely tracked in real-time to compensate for natural movement. Subjects reported the color appearance of each spot. A majority of L-and M-cones consistently gave rise to the sensation of white, while a smaller group repeatedly elicited hue sensations. When blue sensations were reported they were more likely mediated by M- than L-cones. Blue sensations were elicited from M-cones against a short-wavelength light that preferentially elevated the quantal catch in surrounding S-cones, while stimulation of the same cones against a white background elicited green sensations. In one of two subjects, proximity to S-cones increased the probability of blue reports when M-cones were probed. We propose that M-cone increments excited both green and blue opponent pathways, but the relative activity of neighboring cones favored one pathway over the other.
Verification of Hierarchical Artifact Systems

Data-driven workflows, of which IBM’s Business Artifacts are a prime exponent, have been successfully deployed in practice, adopted in industrial standards, and have spawned a rich body of research in academia, focused primarily on static analysis. The present work represents a significant advance on the problem of artifact verification by considering a much richer and more realistic model than in previous work, incorporating core elements of IBM’s successful Guard-Stage-Milestone model. In particular, the model features task hierarchy, concurrency, and richer artifact data. It also allows database key and foreign key dependencies, as well as arithmetic constraints. The results show decidability of verification and establish its complexity, making use of novel techniques including a hierarchy of Vector Addition Systems and a variant of quantifier elimination tailored to our context.
APEX: A Prime EXperiment at Jefferson Lab

APEX is an experiment at Thomas Jefferson National Accelerator Facility (JLab) in Virginia, USA, that searches for a new gauge boson (A') with sub-GeV mass and coupling to ordinary matter of g' ∼ (10{sup −6} − 10{sup −2})e. Electrons impinge upon a fixed target of high-Z material. An A' is produced via a process analogous to photon bremsstrahlung, decaying to an e{sup +}e{sup -} pair. A test run was held in July of 2010, covering m{sub A′} = 175 to 250 MeV and couplings g′/e > 10{sup −3}. A full run is approved and will cover m{sub A′} ∼65 to 525 MeV and g′/e > 2.3 × 10{sup −4}.
Geometric construction of N=2 gauge theories

In this lecture we give a brief, elementary introduction to the natural realization of non-perturbative N = 2 quantum field theories as a low energy limit of classical string theory. We review the systematic construction of six, five, and four dimensional gauge theories using geometrical data, which provides also the exact, non-perturbative solution via mirror symmetry. This construction has lead to the exact solution of a large class of gravity free gauge theories, including Super Yang Mills (SYM) theories as well as non-conventional quantum field theories without a known Lagrangian description.
Intramolecular regioselective insertion into unactivated prochiral carbon-hydrogen bonds with diazoacetates of primary alcohols catalyzed by chiral dirhodium(II) carboxamidates. Highly enantioselective total synthesis of natural lignan lactones

Intramolecular insertion into unactivated prochiral C−H bonds of 3-aryl-1-propyl diazoacetates catalyzed by dirhodium(II) tetrakis[methyl 1-(3-phenyl propanoyl)imidazolidin-2-one-4(R or S)-carboxylate], Rh2(4R-MPPIM)4 or Rh2(4S-MPPIM)4, occurs in 91−96% ee and with virtually complete regiocontrol for the formation of β-benzyl-γ-butyrolactones. This methodology has been applied to the total synthesis of dibenzylbutyrolactone lignans (−)- and (+)-enterolactone, (−)- and (+)-hinokinin, and (+)-arctigenin from substituted cinnamic acids in 19−27% overall yields. Aryltetralin lignan (+)-isodeoxypodophyllotoxin was prepared from the reactant 3,4-(methylenedioxy)cinnamic acid in 36% yield overall, and the lactone precursor to (+)-isolauricerisinol was formed in 96.5% ee and 23% yield overall. Applications of the chiral Rh2(MPPIM)4 catalysts to fully aliphatic systems resulting in the formation of β-substituted-γ-butyrolactones with high regiocontrol and with 93−96% ee have demonstrated the generality of this met...
The First Method for Protection−Deprotection of the Indole 2,3-π Bond

The scope and generality of a new reaction of indoles with MTAD is discussed. In most cases the ene-type reaction proceeds within seconds or minutes at 0 °C to provide the urazole adducts in high yield. This reaction provides the first method for protecting the indole 2,3-double bond since the urazole adducts can be reconverted to the starting indole (retro-ene) simply by heating.
Synthesis and investigation of 1,6-bis-di-tert-butylphosphinohexane and its application in Suzuki–Miyaura coupling

Abstract Palladium catalysts have excellent compounds used in generating difficult carbon–carbon bonds. The development of these palladium catalysts has been the attention of much research. The use of alkyl-phosphines has led to many very active, bulky ligands for palladium catalysts. We report a convenient synthesis of 1,6-bis-di- tert -butylphosphinohexane (DTBPH) and its evaluation in palladium catalyzed Suzuki–Miyaura coupling. The combination of DTBPH and palladium has led to excellent productivity when used as catalyst for Suzuki coupling.
Synthesis and Structure of a New Heptaborate Oxoanion Isomer : B7O9(OH)52-

The nonmetal borate [H3N(CH2)7NH3][B7O9(OH)5]·H2O (1) was prepared via a neat reaction of 1,7-diaminoheptane with excess boric acid under mild nonhydrothermal conditions. Single-crystal X-ray characterization of 1 revealed a new isomer of the heptaborate anion, B7O9(OH)52−. The heptaborate anion in 1 is comprised of four fused (BO)3 rings sharing three four-coordinate boron atoms and a single three-coordinate oxygen atom. This anion is a structural isomer of another recently described heptaborate anion, consisting of a chain of three (BO)3 rings. Compound 1 crystallized in the triclinic space group P1 with a = 9.3266(17) A, b = 10.1222(19) A, c = 10.847(2) A, α = 89.422(2)°, β = 82.349(2)°, γ = 75.158(2)°, V = 980.7(3) A3, and Z = 2.
Inflation: From Theory To Observation and Back

Alan Guth introduced cosmologists to inflation at the 1980 Texas Symposium. Since, inflation has had almost as much impact on cosmology as the big-bang model itself. However, unlike the big-bang model, it has little observational support. Hopefully, that situation is about to change as a variety and abundance of data begin to test inflation in a significant way. The observations that are putting inflation to test involve the formation of structure in the Universe, especially measurements of the anisotropy of the cosmic background radiation. The cold dark matter models of structure formation motivated by inflation are holding up well as the observational tests become sharper. In the next decade inflation will be tested even more significantly, with more precise measurements of CBR anisotropy, the mean density of the Universe, the Hubble constant, and the distribution of matter, as well as sensitive searches for the nonbaryonic dark matter predicted to exist by inflation. As an optimist I believe that we may be well on our way to a standard cosmology that includes inflation and extends back to around 10^{-32} sec, providing an important window on the earliest moments and fundamental physics.
Stable memory and computation in randomly rewiring neural networks.

Recent research suggests that synapses turn over rapidly in some brain structures; however, memories seem to persist for much longer. We show that Hebbian plasticity of synaptic strengths during re...
Synthesis, characterization and crystal structure of oxobis(p-thiocresolato)terpyridinerhenium(V), a new cationic, six-coordinate thiolato complex of rhenium

Abstract The new six-coordinate rhenium(V) complex, oxobis( p -thiocresolato)terpyridinerhenium(V), was synthesized from [ReO 2 (py) 4 ]CF 3 SO 3 and characterized by elemental analysis, thin-layer chromatography, FAB mass spectroscopy, IR and 1 H NMR of the perrhenate salt, as well as by a single crystal X-ray structure determination of the hexafluorophosphate salt. This characterization establishes the structure of the complex in both solid state and solution to be the symmetrical mer(N,N,N),trans(S,S) species in which the central N atom of the terpyridine ligand is situated trans to the ReO linkage. The X-ray and NMR studies demonstrate that the solution and solid state structures are identical.
Polymorphism, phase transitions, and thermal expansion of K3Lu(PO4)2

Abstract Alkali rare-earth double phosphates have been studied for use as long-wavelength scintillators for γ-ray detection using Si photodiodes. Single-crystal and powder X-ray diffraction (XRD) and powder neutron diffraction have been used to study the structure as a function of temperature. K3Lu(PO4)2 crystallizes with a hexagonal unit cell at room temperature, space group P 3 ¯ . The Lu ion is six-coordinated to the oxygen atoms of the phosphate groups. Two lower-temperature phases were characterized using single-crystal XRD and powder neutron diffraction. The first transition occurs at 230 K with a transformation to a monoclinic P21/m space group symmetry, and the Lu retains six coordination. The second phase transition occurs at 130 K, with a large change in the cell volume, keeping the same P21/m space group symmetry; however, one of the phosphate groups rotates to increase the coordination of the Lu ion to seven. This is an unusual example of an isosymmetric phase transition with a coordination change, driven by temperature. High-temperature powder neutron diffraction and high-temperature powder XRD have been used to study the thermal expansion of K3Lu(PO4)2 and indicate a large thermal expansion anisotropy. The crystallographic axes with largest changes account for the structural collapse, which rotates the phosphate group to increase the Lu coordination. The lowest temperature form of K3Lu(PO4)2 is the same as the room temperature form for all the lighter RE compounds of the same type, which is not surprising, given the lighter (larger) RE ions would prefer a higher coordination number.
Speciation genes are more likely to have discordant gene trees

Speciation genes are responsible for reproductive isolation between species. By directly participating in the process of speciation, the genealogies of isolating loci have been thought to more faithfully represent species trees. The unique properties of speciation genes may provide valuable evolutionary insights and help determine the true history of species divergence. Here, we formally analyze whether genealogies from loci participating in Dobzhansky-Muller (DM) incompatibilities are more likely to be concordant with the species tree under incomplete lineage sorting (ILS). Individual loci differ stochastically from the true history of divergence with a predictable frequency due to ILS, and these expectations-combined with the DM model of intrinsic reproductive isolation from epistatic interactions-can be used to examine the probability of concordance at isolating loci. Contrary to existing verbal models, we find that reproductively isolating loci that follow the DM model are often more likely to have discordant gene trees. These results are dependent on the pattern of isolation observed between three species, the time between speciation events, and the time since the last speciation event. Results supporting a higher probability of discordance are found for both derived-derived and derived-ancestral DM pairs, and regardless of whether incompatibilities are allowed or prohibited from segregating in the same population. Our overall results suggest that DM loci are unlikely to be especially useful for reconstructing species relationships, even in the presence of gene flow between incipient species, and may in fact be positively misleading.
Dysprosium(III) catalysis in organic synthesis

Review: dysprosium(III) salts as extremely mild and efficient Lewis acid catalysts for numerous types of carbon—carbon bond forming reactions; 56 refs.
Selectivity Reversal during Thia-Michael Additions Using Tetrabutylammonium Hydroxide: Operationally Simple and Extremely High Turnover

The use of tetrabutylammonium hydroxide as a novel and exceedingly efficient thia-Michael addition catalyst is herein described. This extremely simple methodology allows for the conjugate addition of a wide variety of mercaptan nucleophiles, and functions remarkably well with a very wide range of both classical and non-classical Michael acceptors. Contradistinctive to current literature reports, the use of this catalyst more efficiently promotes the addition of more basic thiols. This methodology is especially attractive and operationally simple, as it generally proceeds with only 1 mol% catalytic loading and without excess reagent, and the produced products typically require no purification.
Total Syntheses of (±)-Isosteviol and (±)-Beyer-15-ene-3β,19-diol by Manganese(III)-Based Oxidative Quadruple Free-Radical Cyclization

Tetraene 1 was prepared in nine steps from the known propargylic alcohol 7 in 17% overall yield or as a 2:1 E/Z mixture in only five steps in 7% overall yield. Oxidative cyclization of 1 with 2 equiv of Mn(OAc)3·2H2O and 1 equiv of Cu(OAc)2 in MeOH at 25 °C provided 35% of tetracycle 2. Further elaboration provided (±)-isosteviol (3) in six steps in 51% yield and (±)-beyer-15-ene-3β,19-diol in four steps in 17% yield.
Synthesis of novel 1,3-oxazino[6,5-b]indole-2,4-(3H,9H)-dione and 2H-1,3,5-oxadiazino[3,2-a]indole-2,4-(3H)-dione from oxindoles

Two novel tricyclic ring systems were designed as serine protease inhibitors and synthesized from oxindoles; the first series, 1,3-oxazino[6,5-b]indole-2,4-(3H,9H)-diones, were prepared from 2,3-dihydro-2-oxo-(1H)-indole-3-carboxamides and phosgene in tetrahydrofuran with triethylamine. The second, a 2H-1,3,5-oxadiazino[3,2-a]indole-2,4-(3H)-dione was made using a similar cyclization on 2,3-dihydro-2-oxo-N-phenyl-(1H)-indole-1-carboxamide.
A Simple and Versatile Route to Novel Conjugated β-Enaminonitriles and Their Application for the Highly Regioselective Synthesis of Nicotinonitriles Using a Vilsmeier-Type Reagent

A straightforward synthesis of conjugated β-enaminonitriles from ketones and β-aminocrotononitrile mediated by TiCl4 is described. The reaction of these novel dienamines with a Vilsmeier-type reagent provides a mild and highly regioselective route for the preparation of nicotinonitriles.
Three Lowest-Lying Electronic States of NH2

The three lowest-lying electronic states, X 2B1, A 2A1, and B 2B2, as well as the lowest linear 2Π stationary point of NH2 have been investigated systematically using ab initio electronic structure theory. The SCF, CASSCF, CISD, CASSCF-SOCI, CCSD, and CCSD(T) levels of theory have been employed to determine total energies, equilibrium structures, and physical properties including dipole moments, harmonic vibrational frequencies, and infrared intensities of NH2. According to the instability analysis of the reference SCF wave functions, physical properties of the three lowest-lying equilibrium states of NH2 may be obtained correctly in the variational sense with all wave functions employed in this study. The lowest linear stationary point (2Π) possesses two distinct imaginary vibrational frequencies along the bending coordinate, indicating a strong Renner−Teller interaction. The predicted geometries and physical properties of the two lowest states of NH2 are in good agreement with available experimental r...
Structure and composition requirements for deoxygenation, dehydration, and ketonization reactions of carboxylic acids on TiO2(001) single-crystal surfaces

Abstract The reactivities of TiO2(001) single-crystal surfaces for acetic acid decomposition were studied by TPD and XPS. Surface structure and composition were varied by a combination of argon ion bombardment and annealing in order to investigate reaction selectivity and to identify the active sites responsible for adsorption and decomposition. Acetic acid adsorbed both molecularly and dissociatively at 200 K, but only dissociatively at 300 K. The molecular species desorbed readily below 300 K. Approximately 15% of the dissociatively adsorbed species (acetates) desorbed as acetic acid at 390 K via recombination with surface hydroxyls. The remaining acetates decomposed at higher temperatures via three different reaction pathways with selectivities dependent on surface composition and structure. Reduced surfaces containing Ti cations of lower valences favored direct deoxygenation of the acetates to fill the oxygen vacancies of the surface. This reaction occurred even at room temperature and deposited atomic carbon on the surface. Oxidized surfaces containing only Ti4+ cations favored reactions to form volatile molecular products. On the {011}-faceted surface, surface acetates decomposed via net unimolecular dehydration to ketene. On the {114}-faceted surface, the bimolecular reaction of surface acetates to form acetone also took place. The reactions of propionates formed by dissociation of propionic acid were directly analogous to those of acetates: methyl ketene was produced by net unimolecular dehydration on the {011}-faceted surface and 3-pentanone was the bimolecular ketonization product on the {114}-faceted surface. Since the {011}-faceted surface exposes only Ti4+ cations of fivefold oxygen coordination, these sites were determined to be responsible for the net unimolecular dehydration. Bimolecular ketonization required the coordination of two acetates to a common Ti4+ cation on a stoichiometric surface. Of the single-crystal surfaces examined, only the {114}-faceted surface presented the necessary fourfold oxygen-coordinated Ti4+ sites for this reaction.
Conjuring a Supernatural Product – DelMarine

The asmarine alkaloids constitute a small family of terpene-nucleobase marine metabolites defined by a unique N-hydroxy-diazepine pharmacophore that effects moderate to potent cytotoxicity against several cancer cell lines. Isolation of the metabolites from an unidentified producer organism provided enough material for initial assay, but this material was soon exhausted, impeding further study. Procurement of material through synthesis is the obvious solution. Here we chronicle our discovery of simple but potent asmarine analogues that solve the material supply problem. 1 Introduction 2 Project Selection 3 Project Design 3.1 The Big Picture 3.2 Synthetic Strategy 3.3 Challenges in the Design 4 The Quest to Find Bioactive Asmarines 4.1 Model Systems as Proof of Concepts 4.2 Stereoselectivity Investigation with Clerodane-Appended Cyclization Precursors 4.2.1 Obtaining the Cyclization Precursor 4.2.2 Results from Cyclization Screening 4.3 Toward the Synthesis of Asmarine A 4.4 A Turning Point: Screening Forward 5 Biological Investigation of the Asmarine Scaffold 5.1 Cytotoxicity Assays of our Synthetic Intermediates and their Enantiomers 5.2 Synthesis of Analogues for a More In-Depth Biological Investigation 6 Synthesis of Simple Asmarine Analogues and their Cytotoxicity 7 Conclusion
Dissecting the Genetic Architecture of Shoot Growth in Carrot (Daucus carota L.) Using a Diallel Mating Design

Crop establishment in carrot ( Daucus carota L.) is limited by slow seedling growth and delayed canopy closure, resulting in high management costs for weed control. Varieties with improved growth habit ( i.e. , larger canopy and increased shoot biomass) may help mitigate weed control, but the underlying genetics of these traits in carrot is unknown. This project used a diallel mating design coupled with recent Bayesian analytical methods to determine the genetic basis of carrot shoot growth. Six diverse carrot inbred lines with variable shoot size were crossed in WI in 2014. F1 hybrids, reciprocal crosses, and parental selfs were grown in a randomized complete block design with two blocks in WI (2015) and CA (2015, 2016). Measurements included canopy height, canopy width, shoot biomass, and root biomass. General and specific combining abilities were estimated using Griffing’s Model I, which is a common analysis for plant breeding experiments. In parallel, additive, inbred, cross-specific, and maternal effects were estimated from a Bayesian mixed model, which is robust to dealing with data imbalance and outliers. Both additive and nonadditive effects significantly influenced shoot traits, with nonadditive effects playing a larger role early in the growing season, when weed control is most critical. Results suggest the presence of heritable variation and thus potential for improvement of these phenotypes in carrot. In addition, results present evidence of heterosis for root biomass, which is a major component of carrot yield.
Solid Oxide Fuel Cells: Fundamentals to Systems

The U.S. Department of Energy (DOE) Office of Fossil Energy's (FE) National Energy Technology Laboratory (NETL), in partnership with private industry, educational institutions and national laboratories, is leading the development and demonstration of high efficiency solid oxide fuel cells (SOFCs) and fuel cell-turbine (FCT) hybrid power generation systems for distributed generation (DG) markets. The DOE FE DG program has three aspects: the Solid State Energy Conversion Alliance (SECA), Fuel Cell Coal Based Systems for central power, and the High Temperature Electrochemistry Center (HiTEC). NETL is partnering with Pacific Northwest National Laboratory (PNNL) in developing new directions in research under SECA for the development and commercialization of modular, low cost, and fuel flexible SOFC systems. The SECA initiative, through advanced materials, processing, and system integration research and development (R&D), will bring SOFC system cost to $400 per kilowatt (kW) by 2010 for stationary and auxiliary power unit (APU) markets. The SECA program is currently structured to include six competing industry teams supported by a crosscutting core technology program (CTP). DOE is ultimately concerned with coal-based central power plants. Advanced aspects of solid oxide technology are part of HiTEC R&D.
Metal-mediated allylation of mucohalic acids: facile formation of γ-allylic α,β-unsaturated γ-butyrolactones ☆

Abstract Mucohalic acids {mucochloric acid ( 1 , 3,4-dichloro-5-hydroxy-5 H -furan-2-one and mucobromic acid ( 2 , 3,4-dibromo-5-hydroxy-5 H -furan-2-one)} were employed as aldehydes in the indium- and tin-mediated Barbier-type allylation reactions and afforded γ-allylic α,β-unsaturated γ-butyrolactones in good to excellent yield.
An unprecedented iron-catalyzed cross-coupling of primary and secondary alkyl Grignard reagents with non-activated aryl chlorides

The use of N-heterocyclic carbene ligands in the iron-catalyzed cross-coupling of alkyl Grignards has allowed, for the first time, coupling of non-activated, electron rich aryl chlorides. Surprisingly, the tetrahydrate of FeCl2 was found to be a better pre-catalyst than anhydrous FeCl2. Primary Grignard reagents coupled in excellent yields while secondary Grignard reagents coupled in modest yields. The use of acyclic secondary Grignard reagents resulted in the formation of isomers in addition to the desired product. These isomeric products were formed via reversible β-hydrogen elimination, indicating that the cross-coupling proceeds through an ionic pathway.
A synthesis of (+)-salvadione-A.

[reaction: see text] The p-benzoquinone shown is converted to the novel hexacyclic triterpene salvadione-A in four steps.
l1kdeconv: an R package for peak calling analysis with LINCS L1000 data

LINCS L1000 is a high-throughput technology that allows gene expression measurement in a large number of assays. However, to fit the measurements of ~1000 genes in the ~500 color channels of LINCS L1000, every two landmark genes are designed to share a single channel. Thus, a deconvolution step is required to infer the expression values of each gene. Any errors in this step can be propagated adversely to the downstream analyses. We presented a LINCS L1000 data peak calling R package l1kdeconv based on a new outlier detection method and an aggregate Gaussian mixture model (AGMM). Upon the remove of outliers and the borrowing information among similar samples, l1kdeconv showed more stable and better performance than methods commonly used in LINCS L1000 data deconvolution. Based on the benchmark using both simulated data and real data, the l1kdeconv package achieved more stable results than the commonly used LINCS L1000 data deconvolution methods.
Failure to replicate a genetic signal for sex bias in the steppe migration into central Europe

Goldberg et al. (1) used genome-wide ancient DNA data (2) from central European Bronze Age (BA) populations and their three ancestral sources of steppe pastoralists (SP), Anatolian farmers (AF), and European hunter-gatherers (HG) to investigate whether the SP migration into central Europe after 5,000 years ago (3, 4) was sex-biased. By estimating a lower proportion of SP ancestry on the X chromosome (36.6%), which is primarily carried in females, than on the autosomes (61.8%), they suggest that the migration involved a ratio of 5–14 SP males for every female. We attempted to replicate this finding using qpAdm (3), which leverages allele frequency correlations between the admixed (BA) and source (SP, AF, and HG) populations with distant outgroups to eliminate potential biases due to genetic drift … [↵][1]1To whom correspondence may be addressed. Email: lazaridis{at}genetics.med.harvard.edu or reich{at}genetics.med.harvard.edu. [1]: #xref-corresp-1-1
New therapy reduces AIDS passed to fetuses and costs less

The AIDS clinical group protocol of zidovudine (AZT) prophylaxis regimen for HIV-1-infected pregnant women and their babies has been associated with a decrease in vertical HIV-1 transmission in non-breastfeeding women in developmental countries. However, scientists furthermore compared the safety and efficacy of short-course nevirapine or AZT during labour and the first week of life. In an advancement that promises to significantly reduce the incidence of AIDS in children in developing countries, scientists have found a simple new way with nevirapine to prevent mother-to-child transmission of the AIDS virus that also is less costly and markedly more effective than the standard therapy with AZT in the third world. The more practical therapy comes from substituting one marketed drug, nevirapine, for the standard drug, AZT. The cost for the two doses of nevirapine was $4, compared with $268 for AZT regimen now used in developing countries and $815 for the much longer and more complicated course used in the U.S. and other developing countries. It is proposed that wide-scale use of nevirapine in developing countries could potentially prevent 300,000 to 400,000 newborns each year from beginning life infected with HIV.
Estimation of the Near Unit Root Model of Real Exchange Rates

The time-series properties of real exchange rates, on a number of definitions, for 22 industrial countries during 1979-95 were used to re-examine whether PPP holds. It is shown that if real exchange rates reverted to a constant mean slowly, say by five percent a month, then at standard levels of significance we should expect 11 of the 22 series examined to yield evidence of mean reversion and to reject that hypothesis of a unit root. Using models that imply a constant unconditional mean or trend-stationary productivity changes, we find that only one of the 22 real exchange rates shows evidence against unit roots. This low rate of rejection of unit roots in real exchange rates can be construed as evidence against PPP.
Dynamic price discovery: Transparency vs. information design

Abstract This paper studies how information design, via public disclosure of past trade details, affects price discovery in a dynamic market. We model that an informed forward-looking buyer sequentially trades with a series of uninformed sellers (hedgers) with heterogenous hedging motives. We discover that sellers' price discovery over the underlying hidden fundamentals is crucially affected by what they can observe about past trade details. Specifically, (i) the availability of past trade details, paradoxically, makes it easier for the informed party to hide her private information and offer opaque prices. (ii) Post-trade price transparency delays price discovery, but once it happens, it is always perfect. (iii) In contrast, when only past order information is available, price discovery can never be perfect, and can even be in the wrong direction. Finally, we show that our findings are robust for diminishing bargaining power, non-zero outside options, and different trading positions.