cssi/SciSciGPT-SciSciNet huggingface dataset:
Integrated Transmission and Distribution System Power Flow and Dynamic Simulation Using Mixed Three-Sequence/ Three-Phase Modeling

The interactions between distribution and transmission systems have increased significantly in recent years. However, in traditional power system simulation tools, transmission and distribution systems are separately modeled and analyzed. Hence, it is difficult to analyze the impacts of distribution systems on trans-mission systems and their interactions in detail. To facilitate the analysis of integrated transmission and distribution (T&D) systems, a novel modeling framework is proposed in this paper, where the transmission system is modeled as one subsystem in three-sequence detail, while each distribution system connected to it is represented as a subsystem and modeled in three-phase de-tail. With this modeling approach, unbalanced conditions at the boundary between T&D systems and within the transmission system can be represented. The integrated T&D power flow is solved by iteratively solving a three-sequence power flow for the transmission system and a three- phase power flow for each distribution system. Furthermore, a new dynamic simulation algorithm for integrated T&D system is proposed. The main challenge in developing this integrated T&D dynamic simulation is associated with different network representations in the trans-mission and distribution systems. With a partitioned solution approach adopted for dynamic simulation, the Multi-Area Thevenin Equivalent (MATE) approach is utilized in the network solution step to address this challenge. The proposed algorithms have been tested against an all electromagnetic transient simulation.
Effect of Sting Geometry on Axial Force Calculation for the Space Launch System

The primary purpose of this study is to determine the extent to which the size and shape of the wind tunnel sting affect the accuracy of the base pressure corrections applied to measured axial force. The study also includes an assessment of the overall accuracy of the corrections. To accomplish these goals, Computational Fluid Dynamics is used to simulate a simplified version of the geometry of the Space Launch System Block 1B Cargo configuration, paired with a range of wind tunnel sting sizes, over a variety of ascent flight conditions. The base pressure correction method used in the wind tunnel is emulated on the base pressures from the simulated flows and results are compared to direct integration of the base pressures. Differences in results between the two methods provides an assessment of the accuracy of the base force correction method and how that accuracy is affected by sting size.
Using Machine Learning Techniques to Classify and Predict Static Code Analysis Tool Warnings

This paper discusses our work on using software engineering metrics (i.e., source code metrics) to classify an error message generated by a Static Code Analysis (SCA) tool as a true-positive, false-positive, or false-negative. Specifically, we compare the performance of Support Vector Machine (SVM), K-Nearest Neighbor (KNN), Random Forests, and Repeated Incremental Pruning to Produce Error Reduction (RIPPER) over eight datasets. The performance of the techniques is assessed by computing the F-measure metric, which is defined as the weighted harmonic mean of the precision and recall of the predicted model. The overall results of the study show that the F-measure value of the predicted model, which is generated using Random Forests technique, ranges from 83% to 98%. Additionally, the Random Forests technique outperforms the other techniques. Lastly, our results indicate that the complexity and coupling metrics have the most impact on whether a SCA tool with generate a false-positive warning or not.
A nonlocal functional promoting low-discrepancy point sets

Abstract Let X = x 1 , … , x N ⊂ T d ≅ [ 0 , 1 ] d be a set of N points in the d − dimensional torus that we want to arrange as regularly possible. The purpose of this paper is to introduce the energy functional E ( X ) = ∑ 1 ≤ m , n ≤ N m ≠ n ∏ k = 1 d ( 1 − log 2 sin π | x m , k − x n , k | ) and to suggest that moving a set X into the direction − ∇ E ( X ) may have the effect of increasing regularity of the set in the sense of decreasing discrepancy. We numerically demonstrate the effect for Halton, Hammersley, Kronecker, Niederreiter and Sobol sets. Lattices in d = 2 are critical points of the energy functional, some (possibly all) are strict local minima.
Adrenergic agonist induces rhythmic firing in quiescent cardiac preganglionic neurons in nucleus ambiguous via activation of intrinsic membrane excitability.

Cardiac preganglionic cholinergic neurons in the nucleus ambiguus (NAm) are responsible for slowing cardiac pacemaking. This study identified that adrenergic agonists can induce rhythmic action pot...
An Innovation Theory of Headquarters Value in Multibusiness Firms

A fundamental question in corporate strategy is how headquarters in multibusiness firms can create value above and beyond the burden of its own overhead. The leading theories from Chandler and Will...
Slide-seq: A scalable technology for measuring genome-wide expression at high spatial resolution

Spatial positions of cells in tissues strongly influence function, yet a high-throughput, genome-wide readout of gene expression with cellular resolution is lacking. We developed Slide-seq, a method for transferring RNA from tissue sections onto a surface covered in DNA-barcoded beads with known positions, allowing the locations of the RNA to be inferred by sequencing. Using Slide-seq, we localized cell types identified by single-cell RNA sequencing datasets within the cerebellum and hippocampus, characterized spatial gene expression patterns in the Purkinje layer of mouse cerebellum, and defined the temporal evolution of cell type-specific responses in a mouse model of traumatic brain injury. These studies highlight how Slide-seq provides a scalable method for obtaining spatially resolved gene expression data at resolutions comparable to the sizes of individual cells.
Studies directed toward the total synthesis of kabiramide C: Asymmetric synthesis of the C7–C19 fragment

Abstract The synthesis of the C7 C19 tris-oxazole fragment 4 of kabiramide C via a BF3·OEt2 promoted condensation between dimethyl acetal 12 and (S)-silane 6 as the crucial synthetic step is described.
SigAttack: New High-level SAT-based Attack on Logic Encryptions

Logic encryption is a powerful hardware protection technique that uses extra key inputs to lock a circuit from piracy or unauthorized use. The recent discovery of the SAT-based attack with Distinguishing Input Pattern (DIP) generation has rendered all traditional logic encryptions vulnerable, and thus the creation of new encryption methods. However, a critical question for any new encryption method is whether security against the DIP-generation attack means security against all other attacks. In this paper, a new high-level SAT-based attack called SigAttack has been discovered and thoroughly investigated. It is based on extracting a key-revealing signature in the encryption. A majority of all known SAT-resilient encryptions are shown to be vulnerable to SigAttack. By formulating the condition under which SigAttack is effective, the paper also provides guidance for the future logic encryption design.
In silico learning of tumor evolution through mutational time series

Cancer arises through the accumulation of somatic mutations over time. Understanding the sequence of mutation occurrence during cancer progression can assist early and accurate diagnosis and improve clinical decision-making. Here we employ long short-term memory (LSTM) networks, a class of recurrent neural network, to learn the evolution of a tumor through an ordered sequence of mutations. We demonstrate the capacity of LSTMs to learn complex dynamics of the mutational time series governing tumor progression, allowing accurate prediction of the mutational burden and the occurrence of mutations in the sequence. Using the probabilities learned by the LSTM, we simulate mutational data and show that the simulation results are statistically indistinguishable from the empirical data. We identify passenger mutations that are significantly associated with established cancer drivers in the sequence and demonstrate that the genes carrying these mutations are substantially enriched in interactions with the corresponding driver genes. Breaking the network into modules consisting of driver genes and their interactors, we show that these interactions are associated with poor patient prognosis, thus likely conferring growth advantage for tumor progression. Thus, application of LSTM provides for prediction of numerous additional conditional drivers and reveals hitherto unknown aspects of cancer evolution.
Distributed and Streaming Linear Programming in Low Dimensions

We study linear programming and general LP-type problems in several big data (streaming and distributed) models. We mainly focus on low dimensional problems in which the number of constraints is much larger than the number of variables. Low dimensional LP-type problems appear frequently in various machine learning tasks such as robust regression, support vector machines, and core vector machines. As supporting large-scale machine learning queries in database systems has become an important direction for database research, obtaining efficient algorithms for low dimensional LP-type problems on massive datasets is of great value. In this paper we give both upper and lower bounds for LP-type problems in distributed and streaming models. Our bounds are almost tight when the dimensionality of the problem is a fixed constant.
Differential RAID: rethinking RAID for SSD reliability

SSDs exhibit very different failure characteristics compared to hard drives. In particular, the Bit Error Rate (BER) of an SSD climbs as it receives more writes. As a result, RAID arrays composed from SSDs are subject to correlated failures. By balancing writes evenly across the array, RAID schemes can wear out devices at similar times. When a device in the array fails towards the end of its lifetime, the high BER of the remaining devices can result in data loss. We propose Diff-RAID, a parity-based redundancy solution that creates an age differential in an array of SSDs. Diff-RAID distributes parity blocks unevenly across the array, leveraging their higher update rate to age devices at different rates. To maintain this age differential when old devices are replaced by new ones, Diff-RAID reshuffles the parity distribution on each drive replacement. We evaluate Diff-RAID's reliability by using real BER data from 12 flash chips on a simulator and show that it is more reliable than RAID-5, in some cases by multiple orders of magnitude. We also evaluate Diff-RAID's performance using a software implementation on a 5-device array of 80 GB Intel X25-M SSDs and show that it offers a trade-off between throughput and reliability.
Growth and Characterization of Piezoelectrically Enhanced Acceptor-Type AlGaN/GaN Heterostructures

Acceptor (Mg)-doped AlGaN/GaN heterostructures were grown via MOVPE and compared to similarly doped GaN standard films grown in the same reactor. Chemical analysis of the films, via secondary ion mass spectrometry (SIMS), revealed comparable Mg concentrations of ∼2×1019 atoms/cm3 in all films. The Mg-doped GaN standard sample had a sheet conductance of 7-μS compared to a sheet conductance of 20-μS for an AlGaN/GaN heterostructure. The sheet conductance of the AlGaN/GaN heterostructures was higher due to piezoelectric acceptor doping and modulation doping effects in addition to conventional Mg acceptor doping.
Improved Characteristics of InGaN Multi-Quantum-Well Laser Diodes Grown on Laterally Epitaxially Overgrown GaN on Sapphire

InGaN multi-quantum-well laser diodes have been fabricated on fully-coalesced laterally epitaxially overgrown (LEO) GaN on sapphire. The laterally overgrown ‘wing’ regions as well as the coalescence fronts contained few or no threading dislocations. Laser diodes fabricated on the low-dislocation-density wing regions showed a reduction in threshold current density from 8 kA/cm2 to 3.7 kA/cm2 compared the those on the high-dislocation ‘window’ regions. Laser diodes also showed a two-fold reduction in threshold current density when comparing those on the wing regions to those fabricated on conventional planar GaN on sapphire. The internal quantum efficiency also improved from 3% for laser diodes on conventional GaN on sapphire to 22% for laser diodes on LEO GaN on sapphire.
Multi-theorem Preprocessing NIZKs from Lattices

Non-interactive zero-knowledge (NIZK) proofs are fundamental to modern cryptography. Numerous NIZK constructions are known in both the random oracle and the common reference string (CRS) models. In the CRS model, there exist constructions from several classes of cryptographic assumptions such as trapdoor permutations, pairings, and indistinguishability obfuscation. However, at the time of the initial publication of this work, we did not have constructions of NIZKs from standard lattice assumptions. In this work, we take an initial step toward constructing multi-theorem NIZKs for general $$\mathsf {NP}$$ languages from standard lattice assumptions by considering a relaxation to the preprocessing model and a new model we call the designated-prover model. In the preprocessing model, a setup algorithm generates secret proving and verification keys for the prover and the verifier, respectively. In the designated-prover model, the proving key is secret, but the verification key is public. In both settings, the proving key is used to construct proofs and the verification key is used to check proofs. Finally, in the multi-theorem setting, both the proving and verification keys should be reusable for an unbounded number of theorems without compromising soundness or zero-knowledge. Previous constructions of NIZKs in the preprocessing model that rely on weaker assumptions like one-way functions or oblivious transfer are only secure in a single-theorem setting. Thus, constructing multi-theorem NIZKs in these relaxed models does not seem to be inherently easier than constructing them in the CRS model. In this work, we first construct a multi-theorem preprocessing NIZK argument from context-hiding homomorphic signatures. In fact, the construction is a designated-prover NIZK. We also show that using homomorphic commitments, we can get statistically sound proofs in the preprocessing and designated-prover models. Together with lattice-based instantiations of homomorphic signatures and commitments, we obtain the first multi-theorem NIZKs in the preprocessing and designated-prover models from standard lattice assumptions. Finally, we show how to generalize our construction to obtain a universally composable NIZK (UC-NIZK) in the preprocessing model from standard lattice assumptions. Our UC-NIZK relies on a simple preprocessing protocol based on a new primitive we call blind homomorphic signatures.
Idealized Modeling of the Atmospheric Boundary Layer Response to SST Forcing in the Western Indian Ocean

AbstractThe atmospheric response to sea surface temperature (SST) variations forced by oceanic downwelling equatorial Rossby waves is investigated using an idealized convection-resolving model. Dow...
Beyond multidrug resistance: Leveraging rare variants with machine and statistical learning models in Mycobacterium tuberculosis resistance prediction

Abstract Background The diagnosis of multidrug resistant and extensively drug resistant tuberculosis is a global health priority. Whole genome sequencing of clinical Mycobacterium tuberculosis isolates promises to circumvent the long wait times and limited scope of conventional phenotypic antimicrobial susceptibility, but gaps remain for predicting phenotype accurately from genotypic data especially for certain drugs. Our primary aim was to perform an exploration of statistical learning algorithms and genetic predictor sets using a rich dataset to build a high performing and fast predicting model to detect anti-tuberculosis drug resistance. Methods We collected targeted or whole genome sequencing and conventional drug resistance phenotyping data from 3601 Mycobacterium tuberculosis strains enriched for resistance to first- and second-line drugs, with 1228 multidrug resistant strains. We investigated the utility of (1) rare variants and variants known to be determinants of resistance for at least one drug and (2) machine and statistical learning architectures in predicting phenotypic drug resistance to 10 anti-tuberculosis drugs. Specifically, we investigated multitask and single task wide and deep neural networks, a multilayer perceptron, regularized logistic regression, and random forest classifiers. Findings The highest performing machine and statistical learning methods included both rare variants and those known to be causal of resistance for at least one drug. Both simpler L2 penalized regression and complex machine learning models had high predictive performance. The average AUCs for our highest performing model was 0.979 for first-line drugs and 0.936 for second-line drugs during repeated cross-validation. On an independent validation set, the highest performing model showed average AUCs, sensitivities, and specificities, respectively, of 0.937, 87.9%, and 92.7% for first-line drugs and 0.891, 82.0% and 90.1% for second-line drugs. Our method outperforms existing approaches based on direct association, with increased sum of sensitivity and specificity of 11.7% on first line drugs and 3.2% on second line drugs. Our method has higher predictive performance compared to previously reported machine learning models during cross-validation, with higher AUCs for 8 of 10 drugs. Interpretation Statistical models, especially those that are trained using both frequent and less frequent variants, significantly improve the accuracy of resistance prediction and hold promise in bringing sequencing technologies closer to the bedside.
Students’ solution of arrangement problems and their connection to Cartesian product problems

Two-hour long developmental teaching interviews were conducted with each of 14 sixth grade students, ages 11–12. The purposes of the interviews were to investigate how students solved arrangement p...
Interaction between securitization gains and abnormal loan loss provisions: Credit risk retention and fair value accounting

This study investigates whether managers use asset securitization gains to substitute loan loss provision (LLP) management for earnings management, and, if so, whether the percentage of credit risk retained affects such a relationship. The literature provides evidence that managers have used securitization transactions to boost earnings. Using 2001‒2014 data for a sample of bank holding companies, I find that managers use securitization gains and LLPs as partial substitutes and that earnings management from securitization gains grows at an increasing rate to substitute income increasing LLP management as the level of risk retention increases. These findings are consistent with the argument that the higher the level of risk retention, the greater the potential impact on achieving earnings targets, given banks’ exercise of discretion over securitization gains through estimation of fair value of retained interest. In addition, I document that the substitution effect between the two tools is non‐existent in the post‐SFAS 166/167 period. Taken together, the findings have timely implications for accounting standards by informing the effect of risk retention that I measure through earnings management techniques. Moreover, my findings provide additional support for improved disclosures on assets‐backed securities.
Successful repair of an arteriovesical fistula as a complication after coil embolization for right hypogastric artery aneurysm.

Abstract An 84-year-old man has a history of a right hypogastric artery aneurysm that was excluded with endograft several years ago. His course was complicated by a type II endoleak with an enlarging aneurysm that required multiple attempts of coil embolization. Several years later, he presented with gross hematuria and was found to have embolization coils extruding into his bladder and an arteriovesical fistula. As seen in this case, endovascular intervention for a type II endoleak is not benign. We describe a novel complication of an arteriovesical fistula that necessitated a difficult repair and ultimate revascularization.
Crystal structures of nitronium tetranitratogallate and its reversible solid-state phase transition mediated by nonmerohedral twinning

Single-crystal X-ray crystallographic analyses of [NO2][Ga(NO3)4] reveal that it undergoes a reversible phase transition without any apparent damage to the crystal during repeated temperature cyclings. The room-temperature, noncentrosymmetric, body-centered tetragonal (I 4), polymorph 1 (a = 9.2774(3) A, c = 6.1149(2) A, Z = 2) consists of well-separated nitronium and tetranitratogallate ions. The [Ga(NO3)4]- units exhibit a slightly squashed tetrahedral geometry in which all of the ligands are monodentate. Below approximately 250 K, distortions lower the symmetry to the chiral, body-centered monoclinic nonstandard space group I2. Both components (2a: a = 9.5857(2) A, b = 5.9399(1) A, c = 8.9759(2) A, β = 90.409(1)°, Z = 2. 2b: a = 9.5898(2) A, b = 5.9376(1) A, c = 8.9784(1) A, β = 90.420(1)°, Z = 2) of the nonmerohedrally twinned structure are independently refined and found to be enantiomeric with nearly identical distance and angle parameters. As in the high-temperature polymorph, the cations and an...
Application of polymer-supported triphenyl phosphine in the palladium-catalyzed cyanation reaction under microwave conditions

Abstract A variety of aryl nitriles were prepared in excellent yields from the palladium acetate catalyzed coupling of aryl halides with Zn(CN)2 using polymer-supported triphenyl phosphine as the ligand and dimethylformamide as solvent under microwave irradiation conditions.
Differential Sustained and Transient Temporal Processing Across Visual Streams

How do high-level visual regions process the temporal aspects of our visual experience? While the temporal sensitivity of early visual cortex has been studied with fMRI in humans, temporal processing in high-level visual cortex is largely unknown. By modeling neural responses with millisecond precision in separate sustained and transient channels, and introducing a flexible encoding framework that captures differences in neural temporal integration time windows and response nonlinearities, we predict fMRI responses across visual cortex for stimuli ranging from 33 ms to 20 s. Using this innovative approach, we discovered that lateral category-selective regions respond to visual transients associated with stimulus onsets and offsets but not sustained visual information. Thus, lateral category-selective regions compute moment-to-moment visual transitions, but not stable features of the visual input. In contrast, ventral category-selective regions process both sustained and transient components of the visual input. Our model revealed that sustained channel responses to prolonged stimuli exhibit adaptation, whereas transient channel responses to stimulus offsets are surprisingly larger than for stimulus onsets. This large offset transient response may reflect a memory trace of the stimulus when it is no longer visible, whereas the onset transient response may reflect rapid processing of new items. Together, these findings reveal previously unconsidered, fundamental temporal mechanisms that distinguish visual streams in the human brain. Importantly, our results underscore the promise of modeling brain responses with millisecond precision to understand the underlying neural computations.
Recent Results on Searches for Pentaquark States from STAR at RHIC

We present results on pentaquark searches from nuclear collisions at RHIC with the STAR detector system. An intriguing peak has been observed in the invariant mass distribution of from 18.6 Million d+Au collision events at . The peak centers at a mass 1528 ± 2 ± 5 MeV/c2 and the FWHM ~15 MeV/c2 limited by detector responses. The statistical significance of the peak is 4.2σ. Such a state if confirmed is manifestly exotic and implies a family of isospin one states. A weak signal of less statistical significance (~3σ) has been observed in 5.6M Au+Au collision events at 62.4 GeV. Searches in 10.7M Au+Au collision events at 200 GeV yield no significant signal. The Au+Au results neither confirm nor rule out the d+Au observation as a possible state.
An expedient in situ preparation of symmetrical 1,4-dibenzylpiperazines from benzyl bromides and 2-bromoethylamine hydrobromide

A straightforward synthesis of a variety of 1,4-bis-benzylpiperazines from benzyl halides and 2-bromoethylamine hydrobromide is described.
Synthesis of 1,6-dihydro-5-hydroxy-6-oxo-3-(trifluoromethyl)-4-pyridazinecarboxylates

The reaction of 2-(alkylamino)-3-(trifluoroacetyl)butenedioates (2a-b) with alkyl and aryl hydrazines in ether provides 1,6-dihydro-6-oxo- 3-(trifluoromehtyl)-4-pyridazinecarboxylates as their alkylamine salts (3a-g). The structures of these products are substantiated using 2D nmr and 15 N nmr techniques
The Hamiltonian dynamics of bounded spacetime and black hole entropy: the canonical method

Abstract From first principles, I present a concrete realization of Carlip's idea on black hole entropy from conformal field theory on the horizon in any dimension. The new formulation is free of the inconsistencies encountered in Carlip's formulation. By considering a correct gravity action, of which the variational principle is well defined at the horizon, I derive a correct classical Virasoro generator for the surface deformations at the horizon through the canonical method. The existence of classical Virasoro algebra is crucial in obtaining an operator Virasoro algebra, through canonical quantization, which produces the right central charge and conformal weight ∼ A + /ℏ G for the semiclassical black hole entropy. The coefficient of proportionality depends on the choice of ground state, which has to be put in by hand to obtain the correct numerical factor 1/4 of the Bekenstein–Hawking (BH) entropy. The appropriate ground state is different for rotating and non-rotating black holes but otherwise it has a universality for a wide variety of black holes. As a byproduct of my results, I am led to conjecture that non-commutativity of taking the limit to go to the horizon and computing variation is proportional to the Hamiltonian and momentum constraints . It is shown that almost all the known uncharged black hole solutions satisfy the conditions for the universal entropy formula.
Addition/elimination reactions of ethylsulfonyl pyridines: stereoselective synthesis of vinylpyridine allylic alcohols

Abstract 2-(Phenylsulfonyl)ethyl pyridines can be coupled with aldehydes leading directly to sulfone-eliminated vinylpyridine allylic alcohols. These products are obtained in good yield and with high levels of stereocontrol.
Estimating the Timing of Multiple Admixture Pulses During Local Ancestry Inference

Admixture, the mixing of genetically distinct populations, is increasingly recognized as a fundamental biological process. One major goal of admixture analyses is to estimate the timing of admixture events. Whereas most methods today can only detect the most recent admixture event, here, we present coalescent theory and associated software that can be used to estimate the timing of multiple admixture events in an admixed population. We extensively validate this approach and evaluate the conditions under which it can successfully distinguish one- from two-pulse admixture models. We apply our approach to real and simulated data of Drosophila melanogaster. We find evidence of a single very recent pulse of cosmopolitan ancestry contributing to African populations, as well as evidence for more ancient admixture among genetically differentiated populations in sub-Saharan Africa. These results suggest our method can quantify complex admixture histories involving genetic material introduced by multiple discrete admixture pulses. The new method facilitates the exploration of admixture and its contribution to adaptation, ecological divergence, and speciation.
Rapid energy expenditure estimation for ankle assisted and inclined loaded walking

Estimating energy expenditure with indirect calorimetry requires expensive equipment and several minutes of data collection for each condition of interest. While several methods estimate energy expenditure using correlation to data from wearable sensors, such as heart rate monitors or accelerometers, their accuracy has not been evaluated for activity conditions or subjects not included in the correlation process. The goal of our study was to develop data-driven models to estimate energy expenditure at intervals of approximately one second and demonstrate their ability to predict energetic cost for new conditions and subjects. Model inputs were muscle activity and vertical ground reaction forces, which are measurable by wearable electromyography electrodes and pressure sensing insoles. We developed models that estimated energy expenditure while walking (1) with ankle exoskeleton assistance and (2) while carrying various loads and walking on inclines. Estimates were made each gait cycle or four second interval. We evaluated the performance of the models for three use cases. The first estimated energy expenditure (in Watts) during walking conditions for subjects with some subject specific training data available. The second estimated all conditions in the dataset for a new subject not included in the training data. The third estimated new conditions for a new subject. The mean absolute percent errors in estimated energy expenditure during assisted walking conditions were 4.4%, 8.0%, and 8.1% for the three use cases, respectively. The average errors in energy expenditure estimation during inclined and loaded walking conditions were 6.1%, 9.7%, and 11.7% for the three use cases. For models not using subject-specific data, we evaluated the ability to order the magnitude of energy expenditure across conditions. The average percentage of correctly ordered conditions was 63% for assisted walking and 87% for incline and loaded walking. We have determined the accuracy of estimating energy expenditure with data-driven models that rely on ground reaction forces and muscle activity for three use cases. For experimental use cases where the accuracy of a data-driven model is sufficient and similar training data is available, standard indirect calorimetry could be replaced. The models, code, and datasets are provided for reproduction and extension of our results.
Total synthesis of (+/-)-isoschizogamine.

Isoschizogamine has been prepared for the first time. The synthesis requires eight steps from a readily available ketone starting material and features an aminal-forming cyclization that is based on a proposed biosynthetic transformation.
Excision of zirconium iodide clusters from highly cross-linked solids.

Highly cross-linked cluster precursors KZr6I14B, Zr6I12B, KZr6I14C, and Zr6I12C were successfully excised in deoxygenated water, and the resulting red aqueous solutions of clusters exhibit better k...
Discovery of ZACA reaction : Zr-catalyzed asymmetric carboalumination of alkenes

A single-stage, i.e., degree of polymerization of one, and enantioselective version of the ZieglerNatta alkene polymerization was envisioned as a potentially significant and useful method for catalytic asymmetric C–C bond formation, shortly after the corresponding alkyne version involving Zr-catalyzed alkylalumination of alkynes was discovered in 1978. However, the discovery of such an asymmetric reaction proved to be a major challenge. At least three widely observable unwanted side reactions, i.e., (1) cyclic carbometalation, (2) β-H transfer hydrometalation, and (3) alkene polymerization, represented by the Ziegler-Natta polymerization, were noted and were to be avoided. With Zr as the metal at the catalytic center, we eventually came up with a notion that di- or multiple alkylation of Zr was to be avoided for achieving superior acyclic asymmetric carbometalation. This, in turn, led us to avoid the use of highly nucleophilic alkylmetals containing alkali metals and Mg. Aluminum used in ZieglerNatta polymerization that can selectively monoalkylate Zr proved to be one of a very limited number of favorable metals. Even so, undesirable cyclic carbozirconation can occur in nonpolar solvents via intricate bimetallic routes to cyclic organozirconium species. The vastly different reactant-catalyst stoichiometry and the absence of polymerization promotors, such as methylaluminoxane, in our investigations permit us to ignore the Ziegler-Natta polymerization as a serious and unwanted side reaction, although use of limited amounts of promotors can in some cases accelerate otherwise sluggish ZACA reactions. Selection of the currently used Zr catalysts including (R)- and (S)-(NMI)2ZrCl2, dichlorobis(neomenthylindenyl)zirconium was made by screening 15 or so known chiral zirconocene derivatives. Systematic scientific design and screening of chiral ligands are clearly highly desirable, and efforts along this line are ongoing. Even at the current level of development, however, the ZACA reaction shows considerable promise as an efficient and selective method for catalytic asymmetric C–C bond formation, which has already been used to significantly modernize and improve syntheses of natural products including deoxypolypropionates and isoprenoids of biological and medicinal interest.
Acid-Catalyzed Phenylcyclohexene Oxide Hydrolysis: Role of Para-Phenyl Substituent on Syn:Anti Hydration Ratio

Rate and product studies of the hydronium ion-catalyzed hydrolysis of 1-phenylcyclohexene oxide and its p-methoxy and p-methyl derivatives in 1:9 dioxane−water solutions were carried out under conditions in which the diol products are stable. It is shown that the cis:trans diol ratio from hydrolysis of this series of epoxides does not systematically increase with the electron-donating ability of the para-substituent, contrary to conclusions in the literature. The equilibrium constants and rates for acid-catalyzed approach to equilibration of cis- and trans-1-(p-methoxyphenyl)cyclohexane-1,2-diol and of cis- and trans-1-(p-methylphenyl)cyclohexane-1,2-diol were measured, and the cis-diol was determined to be the more stable isomer in each case. An intermediate in the acid-catalyzed hydrolysis of 1-(p-methoxyphenyl)cyclohexene oxide is trapped, after its rate-limiting formation, by azide ion. For a series of 1-arylcyclohexene oxides, results are interpreted in terms of a mechanism in which there is a discre...
Solid-state chemistry in a microwave oven : Preparation of Pd/Co alloy from cyanogel coordination polymers

Cyanogels are a class of inorganic gels made of coordination polymers, in which transition metal centers are bridged by cyanide ligands. A dehydrated gel formed by the reaction of [PdCl4]2- and [Co(CN)6]3- can be processed in a conventional microwave oven to form ferromagnetic metal alloys. The cyanogel polymer directly absorbs microwave radiation, which leads to sufficient heating of the sample to cause the rapid reduction of the metal.
Carbonic Anhydrase Reactivity, Mutation, and Inhibition Probed with a Model of ab Initio Quantum Chemistry within a Protein

An effective interaction model is presented linking high-level quantum chemistry to a structured environment via semiclassical interaction operators resembling effective core potentials. The model gives transferable results equivalent to a quantum chemical treatment of the complete system. This is applied to calculations of the reaction pathway for carbonic anhydrase in which a zinc hydroxide species attacks CO2. The reaction path is shown to be compressed by the substrate−peptide contacts so that the end point structures have partial chemical bonds. The controversial binding structure for cyanate inhibitor was found to be closely related to the CO2 bound state due to a proton abstraction facilitated by the enzyme. A mutation to link carbonic anhydrase with other hydrolysis metalloenzymes is also examined. The model accuracy for large systems is confirmed by reproductions of crystal structures as local energy minima and by the approximate agreement of the reaction energetics with known free energies.
Synthesis of 2-Arylcycloalka-2,4-dienones Using Sulfone-Based Methodology

Addition of the anion derived from (phenylthiomethyl)phenyl sulfone to a selection of aryl ω-alkenyl ketones gives adducts that via a sequence of Lewis acid catalyzed rearrangement, α-allylation, and metathesis give rise to 2-thio-4-cycloalkenones. These in turn give cycloalkadienones upon oxidation and elimination. An attempt to develop a polymer-supported variant fails because of the reversibility of sulfone anion addition.
Unusual hysteresis in the magnetic susceptibility of cubic hexaboride KB6.

Electrical resistivity, magnetic susceptibility, and electron paramagnetic resonance measurements were carried out for cubic hexaboride KB6, which is one electron short of completely filling its conduction band. It is found that KB6 is not metallic and has localized spins. KB6 exhibits a highly unusual hysteresis in the magnetic susceptibility below 100 K, which suggests that it undergoes a slow relaxation process.
Cdt1 variants reveal unanticipated aspects of interactions with cyclin/CDK and MCM important for normal genome replication

The earliest step in DNA replication is origin licensing, which is the DNA loading of minichromosome maintenance (MCM) helicase complexes. The Cdc10-dependent transcript 1 (Cdt1) protein is essential for MCM loading during the G1 phase of the cell cycle, but the mechanism of Cdt1 function is still incompletely understood. We examined a collection of rare Cdt1 variants that cause a form of primordial dwarfism (the Meier-Gorlin syndrome) plus one hypomorphic Drosophila allele to shed light on Cdt1 function. Three hypomorphic variants load MCM less efficiently than wild-type (WT) Cdt1, and their lower activity correlates with impaired MCM binding. A structural homology model of the human Cdt1-MCM complex positions the altered Cdt1 residues at two distinct interfaces rather than the previously described single MCM interaction domain. Surprisingly, one dwarfism allele (Cdt1-A66T) is more active than WT Cdt1. This hypermorphic variant binds both cyclin A and SCFSkp2 poorly relative to WT Cdt1. Detailed quantitative live-cell imaging analysis demonstrated no change in the stability of this variant, however. Instead, we propose that cyclin A/CDK inhibits the Cdt1 licensing function independent of the creation of the SCFSkp2 phosphodegron. Together, these findings identify key Cdt1 interactions required for both efficient origin licensing and tight Cdt1 regulation to ensure normal cell proliferation and genome stability.
Enantioselective Cu-catalyzed conjugate addition of diethylzinc to acyclic aliphatic enones.

A new P-chiral phosphine bis(sulfonamide) ligand has been developed that allows the Cu-catalyzed enantioselective conjugate addition of Et2Zn to acyclic aliphatic enones. The reactions proceed with excellent levels of enantioselectivity (90−95% ee) with a range of enone substrates, involve the use of only 1.2 equiv of Et2Zn, and give best results at ambient temperature.
Er7Ni2Te2: The Most Rare-Earth Metal-Rich Ternary Chalcogenide

Er7Ni2Te2 was prepared by solid-state reaction between Er, Er3Ni, and NiTe2. The X-ray single-crystal structure was refined with space group Imm2 (No. 44), a = 15.345(3) A, b = 3.8377(8) A, c = 9.4...
Unexpected Differences in the α-Halogenation and Related Reactivity of Sulfones with Perhaloalkanes in KOH−t-BuOH

Most alkyl phenyl sulfones are readily α-chlorinated with CCl4 and α-brominated with CBrCl3 in KOH−t-BuOH via radical−anion radical pair (RARP) reactions. While isopropyl mesityl sulfone (4) is easily α-chlorinated with CCl4, it was completely recovered when treated with the more reactive CBrCl3. Subsequent investigations showed the latter result to be due to the poor acidity of 4 together with the rapid depletion of CBrCl3 and KOH by their reaction with each other, and led to a variety of other important results. 4-Hydroxyphenyl isopropyl sulfone (6) is unreactive with either CCl4 or CBrCl3 in KOH−t-BuOH, its phenoxide anion strongly reducing the electronegativity of the sulfonyl group, thereby inhibiting α-anion formation. This effect is reversed by the electron-withdrawing influence of two α-phenyls, so that benzhydryl 4-hydroxyphenyl sulfone (8) is readily α-halogenated in KOH−t-BuOH with CCl4 or CBrCl3. On further contact with KOH−t-BuOH the α-halogenated sulfones from 8 are decomposed into benzophen...
Synthesis of 1,1-dialkylindolium-2-thiolates via base-induced transformation of 4-(2-chloro-5-nitrophenyl)-1,2,3-thiadiazole in the presence of secondary amines.

4-(2-Chloro-5-nitrophenyl)-1,2,3-thiadiazole undergoes ring-opening to produce a thioketene intermediate that reacts with secondary amines forming 2-(2-chloro-5-nitrophenyl)-N,N-dialkylthioacetamid...
Agmatine accumulation by Pseudomonas aeruginosa clinical isolates confers antibiotic tolerance and dampens host inflammation.

Purpose. In the cystic fibrosis (CF) airways, Pseudomonas aeruginosa undergoes diverse physiological changes in response to inflammation, antibiotic pressure, oxidative stress and a dynamic bioavailable nutrient pool. These include loss-of-function mutations that result in reduced virulence, altered metabolism and other phenotypes that are thought to confer a selective advantage for long-term persistence. Recently, clinical isolates of P. aeruginosa that hyperproduce agmatine (decarboxylated arginine) were cultured from individuals with CF. Sputum concentrations of this metabolite were also shown to correlate with disease severity. This raised the question of whether agmatine accumulation might also confer a selective advantage for P. aeruginosa during chronic colonization of the lung. Methodology and Results. We screened a library of P. aeruginosa CF clinical isolates and found that ~5 % of subjects harboured isolates with an agmatine hyperproducing phenotype. Agmatine accumulation was a direct result of mutations in aguA, encoding the arginine deiminase that catalyses the conversion of agmatine into various polyamines. We also found that agmatine hyperproducing isolates (aguA-) had increased tolerance to the cationic antibiotics gentamicin, tobramycin and colistin relative to their chromosomally complemented strains (aguA+). Finally, we revealed that agmatine diminishes IL-8 production by airway epithelial cells in response to bacterial infection, with a consequent decrease in neutrophil recruitment to the murine airways in an acute pneumonia model. Conclusion. These data highlight a potential new role for bacterial-derived agmatine that may have important consequences for the long-term persistence of P. aeruginosa in the CF airways.
Last and corresponding authorship practices in ecology

Authorship is intended to convey information regarding credit and responsibility for manuscripts. However, while there is general agreement within ecology that the first author is the person who contributed the most to a particular project, there is less agreement regarding whether being last author is a position of significance and regarding what is indicated by someone being the corresponding author on a manuscript. Using an analysis of papers published in American Naturalist, Ecology, Evolution, and Oikos, I found that: (1) the number of authors on papers is increasing over time; (2) the proportion of first authors as corresponding author has increased over time, as has the proportion of last authors as corresponding author; (3) 84% of papers published in 2016 had the first author as corresponding author; and (4) geographic regions differed in the likelihood of having the first (or last) author as corresponding author. I also carried out an online survey to better understand views on last and corresponding authorship. This survey revealed that most ecologists view the last author as the “senior” author on a paper (i.e., the person who runs the research group in which most of the work was carried out), and most ecologists view the corresponding author as the person taking full responsibility for a paper. However, there was substantial variation in views on authorship, especially corresponding authorship. Given these results, I suggest that discussions of authorship have as their starting point that the first author will be corresponding author and the senior author will be last author. I also suggest ways of deciding author order in cases where two senior authors contributed equally.
Behavioral changes and growth deficits in a CRISPR engineered mouse model of the schizophrenia-associated 3q29 deletion

The 3q29 deletion confers increased risk for neuropsychiatric phenotypes including intellectual disability, autism spectrum disorder, generalized anxiety disorder, and a >40-fold increased risk for schizophrenia. To investigate consequences of the 3q29 deletion in an experimental system, we used CRISPR/Cas9 technology to introduce a heterozygous deletion into the syntenic interval on C57BL/6 mouse chromosome 16. mRNA abundance for 20 of the 21 genes in the interval was reduced by ~50%, while protein levels were reduced for only a subset of these, suggesting a compensatory mechanism. Mice harboring the deletion manifested behavioral impairments in multiple domains including social interaction, cognitive function, acoustic startle, and amphetamine sensitivity, with some sex-dependent manifestations. In addition, 3q29 deletion mice showed reduced body weight throughout development consistent with the phenotype of 3q29 deletion syndrome patients. Of the genes within the interval, DLG1 has been hypothesized as a contributor to the neuropsychiatric phenotypes. However, we show that Dlg1+/- mice did not exhibit the behavioral deficits seen in mice harboring the full 3q29 deletion. These data demonstrate the following: the 3q29 deletion mice are a valuable experimental system that can be used to interrogate the biology of 3q29 deletion syndrome; behavioral manifestations of the 3q29 deletion may have sex-dependent effects; and mouse-specific behavior phenotypes associated with the 3q29 deletion are not solely due to haploinsufficiency of Dlg1.
Modeling of Biomechanics and Biorheology of Red Blood Cells in Type 2 Diabetes Mellitus

Abstract Erythrocytes in patients with type-2 diabetes mellitus (T2DM) are associated with reduced cell deformability and elevated blood viscosity, which contribute to impaired blood flow and other pathophysiological aspects of diabetes-related vascular complications. In this study, by using a two-component red blood cell (RBC) model and systematic parameter variation, we perform detailed computational simulations to probe the alteration of the biomechanical, rheological, and dynamic behavior of T2DM RBCs in response to morphological change and membrane stiffening. First, we examine the elastic response of T2DM RBCs subject to static tensile forcing and their viscoelastic relaxation response upon release of the stretching force. Second, we investigate the membrane fluctuations of T2DM RBCs and explore the effect of cell shape on the fluctuation amplitudes. Third, we subject the T2DM RBCs to shear flow and probe the effects of cell shape and effective membrane viscosity on their tank-treading movement. In addition, we model the cell dynamic behavior in a microfluidic channel with constriction and quantify the biorheological properties of individual T2DM RBCs. Finally, we simulate T2DM RBC suspensions under shear and compare the predicted viscosity with experimental measurements. Taken together, these simulation results and their comparison with currently available experimental data are helpful in identifying a specific parametric model—the first of its kind, to our knowledge—that best describes the main hallmarks of T2DM RBCs, which can be used in future simulation studies of hematologic complications of T2DM patients.