cssi/SciSciGPT-SciSciNet huggingface dataset:
Respiratory Risk Associated With Indoor Air Pollutants in the Form of Settled House Dust

Background: Asthma and allergies are considered by many physicians as being triggered by different substances in the air we breathe. The lung is the most common site of injury by airborne pollutants. Studying of indoor air quality can provide a method for appropriate remedial action. Research suggests that SHD (Settled House Dust) may be a significant source for indoor exposure. This research study consisted of sampling dust from homes in different area codes. The purpose of this research study will display how sampling household dust is a powerful tool for identifying chemicals that contribute to poor indoor air quality. Over the last few decades, the diagnosis of asthma and allergy cases have increased all over the world. Environmental changes are suspected as a possible cause. Studies suggest pollutants in the indoor environment may contribute to the increase incidence of asthma and allergy cases. These pollutants include chemical contaminants (e. g. pesticides, metals, plasticizers) and biological contaminants (e. g. bacteria, molds, viruses, dust mites). Many of these contaminants combined with particulate matter suspended in indoor air that later settles out as house dust. Inhalation of dust can occur when dust is suspended or re-suspended by activities such as vacuuming, cleaning, playing or simply walking through a room. Methods: The study was carried out in Houston and its surrounding areas. The areas were residential with no industrial activities nearby. In the study area, several types of houses were present: multi-story, single floor, houses with many facilities (air-conditioning, air cooling systems, with good ventilation). The occupants of each resident were asked to give background medical history. Dust samples were collected from vacuum bags and air condition filters. Gas chromatography /mass spectrometry was used to analyze all dust samples. Results: There were a variety of chemicals identified. A majority of chemicals identified were consistent with everyday household products. These products included cleaning agents, oils and fragrances. Conclusions: There were several homes in which the chemical phthalates were identified in dust samples. Epidemiological studies have suggested an association between exposure to phthalate plasticizers including DEHP and increased prevalence of asthma, rhinitis or wheezing. It can be concluded; the Settled House Dust Method is a unique and reliable tool for identifying a broad range of chemicals.
Semantically Enhanced Time Series Databases in IoT-Edge-Cloud Infrastructure

Many IoT systems are data intensive and are for the purpose of monitoring for fault detection and diagnosis of critical systems. A large volume of data steadily come out of a large number of sensors in the monitoring system. Thus, we need to consider how to store and manage these data. Existing time series databases (TSDBs) can be used for monitoring data storage, but they do not have good models for describing the data streams stored in the database. In this paper, we develop a semantic model for the specification of the monitoring data streams (time series data) in terms of which sensor generated the data stream, which metric of which entity the sensor is monitoring, what is the relation of the entity to other entities in the system, which measurement unit is used for the data stream, etc. We have also developed a tool suite, SE-TSDB, that can run on top of existing TSDBs to help establish semantic specifications for data streams and enable semantic-based data retrievals. With our semantic model for monitoring data and our SE-TSDB tool suite, users can retrieve non-existing data streams that can be automatically derived from the semantics. Users can also retrieve data streams without knowing where they are. Semantic based retrieval is especially important in a large-scale integrated IoT-Edge-Cloud system, because of its sheer quantity of data, its huge number of computing and IoT devices that may store the data, and the dynamics in data migration and evolution. With better data semantics, data streams can be more effectively tracked and flexibly retrieved to help with timely data analysis and control decision making anywhere and anytime.
Tunable Spin-State Bistability in a Spin Crossover Molecular Complex

The spin crossover (SCO) transitions at both the surface and over the entire volume of the [Fe{H2B(pz)2}2(bipy)] polycrystalline films on Al2O3 substrates have been studied, where pz = pyrazol-1-yl and bipy = 2,2'-bipyridine. For [Fe{H2B(pz)2}2(bipy)] films of hundreds of nm thick, magnetometry and x-ray absorption spectroscopy measurements show thermal hysteresis in the SCO transition with temperature, although the transition in bulk [Fe{H2B(pz)2}2(bipy)] occurs in a non-hysteretic fashion at 157 K. While the size of the crystallites in those films are similar, the hysteresis becomes more prominent in thinner films, indicating a significant effect of the [Fe{H2B(pz)2}2(bipy)]/Al2O3 interface. Bistability of spin states, which can be inferred from the thermal hysteresis, was directly observed using temperature-dependent x-ray diffraction; the crystallites behave as spin-state domains that coexist during the transition. The difference between the spin state of molecules at the surface of the [Fe{H2B(pz)2}2(bipy)] films and that of the molecules within the films, during the thermal cycle, indicates that both cooperative (intermolecular) effects and coordination are implicated in perturbations to the SCO transition.
A k -mer grammar analysis to uncover maize regulatory architecture

Only a small percentage of the genome sequence is involved in regulation of gene expression, but to biochemically identify this portion is expensive and laborious. In species like maize, with diverse intergenic regions and lots of repetitive elements, this is an especially challenging problem that limits the use of the data from one line to the other. While regulatory regions are rare, they do have characteristic chromatin contexts and sequence organization (the grammar) with which they can be identified. We developed a computational framework to exploit this sequence arrangement. The models learn to classify regulatory regions based on sequence features - k-mers. To do this, we borrowed two approaches from the field of natural language processing: (1) “bag-of-words” which is commonly used for differentially weighting key words in tasks like sentiment analyses, and (2) a vector-space model using word2vec (vector-k-mers), that captures semantic and linguistic relationships between words. We built “bag-of-k-mers” and “vector-k-mers” models that distinguish between regulatory and non-regulatory regions with an average accuracy above 90%. Our “bag-of-k-mers” achieved higher overall accuracy, while the “vector-k-mers” models were more useful in highlighting key groups of sequences within the regulatory regions. These models now provide powerful tools to annotate regulatory regions in other maize lines beyond the reference, at low cost and with high accuracy.
Adjoint-Based Optimization of Active Nanophotonic Devices

We combine the adjoint variable method and the multi-frequency finite-difference frequency-domain method for systematic optimization of active nanophotonic devices. As an example, we numerically optimized a dynamic isolator which remains high isolation performance with half the modulation length. © 2019 The Author(s)
Loss of the Heparan Sulfate Proteoglycan Glypican5 Facilitates Long-Range Sonic Hedgehog Signaling

As a morphogen, Sonic Hedgehog (Shh) mediates signaling at a distance from its sites of synthesis. After secretion, Shh must traverse a distance through the extracellular matrix (ECM) to reach the target cells and activate the Hh response. ECM proteins, in particular, the heparan sulfate proteoglycans (HSPGs) of the glypican family, have both negative and positive effects on Shh signaling, all attributed to their ability to bind Shh. Using mouse embryonic stem cell-derived mosaic tissues with compartments that lack the glycosyltransferases Exostosin1 and Exostosin2, or the HSPG core protein Glypican5, we show that Shh accumulates around its source cells when they are surrounded by cells that have a mutated ECM. This accumulation of Shh is correlated with an increased noncell autonomous Shh response. Our results support a model in which Shh presented on the cell surface accumulates at or near ECM that lacks HSPGs, possibly due to the absence of these Shh sequestering molecules. Stem Cells 2019;37:899-909.
Calkin representations for $L^{p}$

We identify the weak closures of the ranges of certain Calkin representations for $$L^{p}$$ , $$1<p<\infty $$ . As a consequence, assuming the continuum hypothesis, we show that the commutant of $$B(L^{p})$$ , $$1<p<\infty $$ , in its ultrapower may or may not be trivial depending on the ultrafilter. This extends a result of Farah, Phillips and Steprāns.
Monopoly capital and innovation: an exploratory assessment of R&D effectiveness

This research note performs some limited empirical assessments of the Baran and Sweezy (1966) contention that most research and development (R&D) efforts in the US are “wasted” at the macroeconomic level in that as R&D succeeds by absorbing a little of the excess economic surplus generated by a capitalist system, it still fails to generate a lot of innovation of a transformative nature. At an aggregate level, greater R&D efforts are correlated with higher worker productivity and standards of living, which is to be expected according to mainstream economic theory and literature. Yet, R&D efforts regarding job creation, new firm creation, and net business investment show either mixed results or even negative connections. There is some preliminary empirical support in this paper for many aspects of the Baran and Sweezy point of view on R&D, and these findings also hint that R&D is used in a monopoly capital system to further monopolization. The findings of this note also may help to explain how productivity gains and innovation over the last few decades may not be benefitting the typical worker or the creation of small businesses as well.
The wewakpeptins, cyclic depsipeptides from a Papua New Guinea collection of the marine cyanobacterium Lyngbya semiplena.

Four new depsipeptides have been isolated from the marine cyanobacterium Lyngbya semiplena collected from Papua New Guinea. The amino and hydroxy acid partial structures of wewakpeptins A−D (1−4) were elucidated through extensive spectroscopic techniques, including HR-FABMS, 1D 1H and 13C NMR, as well as 2D COSY, HSQC, HSQC-TOCSY, and HMBC spectra. The sequence of the residues was determined through a combination of multifaceted approaches including ESI-MS/MS, HMBC, ROESY, and a modified 1D HMBC experiment. The absolute stereochemistry of each residue was determined by chiral HPLC and chiral GC−MS methods. The wewakpeptins represent an unusual arrangement of amino and hydroxy acid subunits relative to known cyanobacterial peptides and possess a bis-ester, a 2,2-dimethyl-3-hydroxy-7-octynoic acid (Dhoya) or 2,2-dimethyl-3-hydroxyoctanoic acid (Dhoaa) residue, and a diprolyl group reminiscent of dolastatin 15. Wewakpeptin A and B were the most cytotoxic among these four depsipeptides with an LC50 of approxi...
Trans- and cis-selective Lewis acid catalyzed hydrogermylation of alkynes.

The first examples of Lewis acid catalyzed hydrogermylation of alkynes have been demonstrated. It was found that this method has much higher functional group compatibility compared to the known Lewis acid catalyzed hydrosilylation and hydrostannation reactions. Remarkably, the stereochemical outcome of this hydrogermylation reaction depends on the nature of the alkyne used: proceeding via a trans-addition pathway with simple alkynes and cis-addition with propiolates. Mechanistic studies strongly support the proposed rationale on the origins of cis-selectivity in the hydrogermylation of activated alkynes.
Genome-wide analysis of genetic predisposition to Alzheimer's disease and related sex disparities.

Alzheimer’s disease (AD) is the most common cause of dementia in the elderly and the sixth leading cause of death in the United States. AD is mainly considered a complex disorder with polygenic inheritance. Despite discovering many susceptibility loci, a major proportion of AD genetic variance remains to be explained. We investigated the genetic architecture of AD in four publicly available independent datasets through genome-wide association, transcriptome-wide association, and gene-based and pathway-based analyses. To explore differences in the genetic basis of AD between males and females, analyses were performed on three samples in each dataset: males and females combined, only males, or only females. Our genome-wide association analyses corroborated the associations of several previously detected AD loci and revealed novel significant associations of 35 single-nucleotide polymorphisms (SNPs) outside the chromosome 19q13 region at the suggestive significance level of p < 5E–06. These SNPs were mapped to 21 genes in 19 chromosomal regions. Of these, 17 genes were not associated with AD at genome-wide or suggestive levels of associations by previous genome-wide association studies. Also, the chromosomal regions corresponding to 8 genes did not contain any previously detected AD-associated SNPs with p < 5E–06. Our transcriptome-wide association and gene-based analyses revealed that 26 genes located in 20 chromosomal regions outside chromosome 19q13 had evidence of potential associations with AD at a false discovery rate of 0.05. Of these, 13 genes/regions did not contain any previously AD-associated SNPs at genome-wide or suggestive levels of associations. Most of the newly detected AD-associated SNPs and genes were sex specific, indicating sex disparities in the genetic basis of AD. Also, 7 of 26 pathways that showed evidence of associations with AD in our pathway-bases analyses were significant only in females. Our findings, particularly the newly discovered sex-specific genetic contributors, provide novel insight into the genetic architecture of AD and can advance our understanding of its pathogenesis.
The sydnone ring as an ortho-director of lithiation. Dilithiation of 3-phenylsydnone and trapping by electrophiles

Abstract Readily available 3-phenylsydnone ( 3 ) reacts with n -butyllithium/TMEDA to form the dilithio species 4 which can be trapped with suitable electrophiles. This represents the first use of a mesoionic ring system for directed lithiation.
ortho-(substituted silyl)phenylsydnones via a novel sydnone to phenyl ring, lithiation-induced silicon migration

3-(2-Bromophenyl)sydnone (5) reacts with LDA then substituted chlorosilanes to form the corresponding 4-silylsydnones 6, which rearrange to the novel ortho-silylphenylsydnones 8 on treatment with n-butyllithium.
Chiral lithiothiophenes as non-transferable ligands in organocuprate conjugate addition reactions

Abstract Non-transferable carbon bound homochiral ligands have been developed for the asymmetric transfer of an alkyl or an aryl group to a prochiral α,β-unsaturated enone with copper reagents. These ligands are based on thiophene and chiral amino alcohols derived from l -proline and ephedrine.
Ambient-Pressure Synthesis of SHG-Active Eu2Ti2O7 with a [110] Layered Perovskite Structure: Suppressing Pyrochlore Formation by Oxidation of Perovskite-Type EuTiO3

Gram-scale quantities of Eu2Ti2O7 with a [110] layered perovskite structure have been synthesized at ambient pressure by thermally oxidizing (750−900 °C) perovskite-type EuTiO3. Eu2Ti2O7 is type 1 phase matchable and shows a SHG efficiency of 80 × α-SiO2.
One step synthesis of dihydropyrrolo[3,2‐e]indoles from 1,4‐cyclohexanedione

Condensation of phenylhydrazones 1a-c with 1,4-cyclohexanedione in the presence of zinc dust, sodium acetate and acetic acid gave the 4,5-dihydropyrrolo[3,2-e]indoles 7a-c. Oxidation of 7a with DDQ afforded the fully aromatic pyrroloindole 16.
Cs4BiAs3Se7: A novel bismuth-selenoarsenate with infinite 1∞[BiAs3Se7]4- chains containing two different anions, [AsSe3]3- and trans-[As2Se4]4-

A new phase has been prepared by methanolothermal reaction of Cs2CO3, BiCl3 and Li3AsSe3 at 130 °C for 36 hours. Cs4BiAs3Se7 (I) reveals the first Bi-selenoarsenate polyanionic chain [Bi(As2Se4)(AsSe3)]4–, consisting of Bi3+ ions in a distorted octahedral environment of [AsSe3]3– and trans-[As2Se4]4– units. The latter anion consists of a central “As24+” dumb-bell whereby two Se atoms are attached to each of the As atoms. Structural Data: Space Group P21/n, a = 13.404(4) A, b = 23.745(8) A, c = 13.880(4) A, β = 99.324(6)°, Z = 8. Cs4BiAs3Se7: Ein neuartiges Bismut-Selenoarsenat mit [BiAs3Se7]4– Ketten und den beiden Anionen [AsSe3]3– and trans-[As2Se4]4– Cs4BiAs3Se7 (I) konnte durch die methanolothermale Reaktion von Cs2CO3 und BiCl3 mit Li3AsSe3 bei 130 °C und 36 Stunden dargestellt werden. I hat die erste Bismut-Selenidoarsenat Polyanion-Kette [Bi(As2Se4)(AsSe3)]4–, in welcher Bi3+ Kationen durch zwei verschiedene Anionen, [AsSe3]3– und trans-[As2Se4]4–, in verzerrt oktaedrischer Umgebung koordiniert werden. Letztgenanntes Anion besteht aus einer hantelformigen „As24+” Einheit, deren Koordination durch je zwei terminale Se-Atome abgesattigt wird. Strukturdaten: Raumgruppe P21/n, a = 13.404(4) A, b = 23.745(8) A, c = 13.880(4) A, β = 99.324(6)°, Z = 8.
Iron-catalyzed cross-coupling of imidoyl chlorides with Grignard reagents

A general, high yielding rapid iron-catalyzed cross-coupling reaction between Grignard reagents and imidoyl chlorides is described. These reactions are typically completed within 5 min, resulting in high yields of 71−96% using 5% iron catalyst in a THF−NMP solvent mixture. Functionalized imidoyl chlorides (e.g., R = CO2Me) gave excellent yields (89%).
Synthesis, structural characterization and properties of SrAl4−xGex, BaAl4−xGex, and EuAl4−xGex (x≈0.3–0.4)—Rare examples of electron-rich phases with the BaAl4 structure type

Abstract Three solid solutions with the general formula AEAl4−xGex (AE=Eu, Sr, Ba; 0.32(1)≤x≤0.41(1)) have been synthesized via the aluminum self-flux method, and their crystal structures have been established from powder and single-crystal X-ray diffraction. They are isotypic and crystallize with the well-known BaAl4 structure type, adopted by the three AEAl4 end members. In all structures, Ge substitutes Al only at the 4e Wyckoff site. Results from X-rays photoelectron spectroscopy on EuAl4−xGex and EuAl4 indicate that the interactions between the Eu2+ cations and the polyanionic framework are enhanced in the Ge-doped structure, despite the slightly elevated Fermi level. Magnetic susceptibility measurements confirm the local moment magnetism, expected for the [Xe]4f7 electronic configuration of Eu2+ and suggest strong ferromagnetic interactions at cryogenic temperatures. Resistivity data from single-crystalline samples show differences between the title compounds, implying different bonding characteristics despite the close Debye temperatures. A brief discussion on the observed electron count and homogeneity ranges for AEAl4−xGex (AE=Eu, Sr, Ba) is also presented.
High-resolution Genomic Surveillance of 2014 Ebolavirus Using Shared Subclonal Variants.

BACKGROUND Viral outbreaks, such as the 2014 ebolavirus, can spread rapidly and have complex evolutionary dynamics, including coinfection and bulk transmission of multiple viral populations. Genomic surveillance can be hindered when the spread of the outbreak exceeds the evolutionary rate, in which case consensus approaches will have limited resolution. Deep sequencing of infected patients can identify genomic variants present in intrahost populations at subclonal frequencies (i.e. <50%). Shared subclonal variants (SSVs) can provide additional phylogenetic resolution and inform about disease transmission patterns. METHODS We use metrics from population genetics to analyze data from the 2014 ebolavirus outbreak in Sierra Leone and identify phylogenetic signal arising from SSVs. We use methods derived from information theory to measure a lower bound on transmission bottleneck size. RESULTS AND CONCLUSIONS We identify several SSV that shed light on phylogenetic relationships not captured by consensus-based analyses. We find that transmission bottleneck size is larger than one founder population, yet significantly smaller than the intrahost effective population. Our results demonstrate the important role of shared subclonal variants in genomic surveillance.
Highly enantioselective catalytic phenylation of ketones with a constrained geometry titanium catalyst.

The catalytic asymmetric addition of phenyl groups from diphenylzinc to ketones is reported. The catalyst, generated from a dihydroxy bis(sulfonamide) ligand and titanium tetraisopropoxide, gives g...
Adsorbate (substrate)-induced restructuring of active transition metal sites of heterogeneous and enzyme catalysts

Adsorbate-induced restructuring of transition metal surfaces and those of transition metal clusters embedded in metalloproteins has been shown to be a dominant phenomenon by LEED surface crystallography and X-ray crystallography studies, respectively. The restructuring is thermodynamically driven and is more facile for low-coordination metal sites (surface defects, steps and kinks, and nanoclusters). Dynamic restructuring of catalytically active transition metal sites may occur on the time scale of catalytic turnover or faster. The structural flexibility of transition metal surfaces and clusters embedded in enzymes could provide for seamless evolutionary changes of catalytic chemistry from inorganic to more complex and selective bio-organic systems.
Total synthesis of (+)-breynolide

Abstract The total synthesis of (+)-breynolide ( 2 ) is described. The primary focus is the synthesis of the advanced aldehyde intermediate 12 , which comprises the cis -fused perhydrobenzothiophene ring system. Three stereoselective cyclohexene epoxidation/epoxide opening sequences and a glycolate ester Claisen rearrangement, by which all of the necessary oxygen functionality in 12 is introduced before installation of the thioether, are employed.
Sodium percarbonate: A convenient reagent for the dakin reaction

Abstract Sodium percarbonate, a readily available, inexpensive and easy to handle reagent efficiently oxidizes hydroxylated benzaldehydes and hydroxylated acetophenones to hydroxyphenols.
Chirospecific Syntheses of Conformationally Constrained 7-Azabicycloheptane Amino Acids by Transannular Alkylation.

A new method is reported for the chirospecific preparation of optically pure 1-carboxy-7-azabicycloheptane amino acids for the generation of peptidomimetics as conformational probes. The method allows for the multigram preparation of these amino acid analogues through use of a thiolactam sulfide contraction and a transannular alkylation sequence as the key C−C bond-forming steps, starting from l-glutamic acid. The route provides access to two common intermediates, 7-(benzyloxycarbonyl)-1-carboxy-7-azabicyclo[2.2.1]-3-heptane and (1S,4R)-7-(benzyloxycarbonyl)-1-carboxy-7-azabicyclo[2.2.1]-3-heptanone tert-butyl ester, for elaboration to symmetrical and chiral amino acid homologues, respectively. Decarboxylation of the C-1 carboxy unit of the latter intermediate also demonstrated the applicability of the method for a short, chirospecific preparation of a (+)-epibatidine intermediate, (1S,4R)-7-(tert-butyloxycarbonyl)-1-carboxy-7-azabicyclo[2.2.1]-3-heptanone.
A review of electrolyte and electrode materials for high temperature electrochemical CO2 and SO2 gas sensors

Abstract Carbon dioxide and sulfur dioxide are two common combustion products, so monitoring their contents in exhaust gases is important to reduce harmful emissions. Solid electrolyte based sensors are well suited to the high temperature aggressive environments in combustion environments. However, the design of effective high temperature electrochemical sensors for CO2 and SO2 requires strategic combinations of electrolyte and electrode materials to provide satisfactory response and stability. The approaches and materials used in the development of CO2 and SO2 sensors, many of which are common to both types of sensors, are reviewed in this paper.
Low-Temperature Matrix Isolation Studies of BCl(N3)2: Infrared Spectra and Photolysis Processes

BCl(N3)2 was isolated in a low-temperature argon matrix and its FTIR spectrum measured. The splitting due to the natural abundances of 10B and 11B and ab initio calculations of the ground-state fre...
Study of the synthesis of poecillanosine

The synthesis of poecillanosine, a natural N-hydroxy-N-nitroso-alkylamine compound, was studied. Poecillanosine was shown to be unstable under acidic nitrosation conditions. Only degradation compounds of poecillanosine were obtained under such conditions, however, the O-methyl derivative of poecillanosine was synthesised and confirmed.
A Positional Scanning Approach to the Discovery of Dipeptide-Based Catalysts for the Enantioselective Addition of Vinylzinc Reagents to Aldehydes

A combinatorial library of dipeptide N-acylethylenediamine-based ligands was synthesized by parallel solid-phase methods. These ligands were screened in crude form as catalysts for the asymmetric addition of vinylzinc reagents to aldehydes to give chiral allylic alcohols. Three sites of diversity on the ligands were optimized using a positional scanning approach. The optimized structure from the library, ligand 54, was found to catalyze the formation of 10 different (E)-allylic alcohols with enantioselectivities ranging from 90% to 95% ee. This ligand was effective for both aromatic and α-branched aldehydes, and vinylzinc reagents derived from both bulky and straight chain terminal alkynes.
Ab Initio Theoretical Studies on the Ring-Opening Modes of the Oxiranyl-, Aziridinyl-, Oxaziridinyl-, and Thiaranylmethyl Radical Systems

Ab initio theoretical studies have been carried out on the oxiranyl-, aziridinyl-, oxaziridinyl-, and thiaranylmethyl radical systems and on the various possible conformations of the ring-opened heteroallyllic radical systems derived by ring opening of the first three systems. Previous theoretical studies on the ring opening of the oxiranylmethyl radical indicated that there is an overwhelming thermodynamic preference for the formation of the allyloxy radical over the formation of the (vinyloxy)methyl radical. The results of the present theoretical studies on the potential energy surfaces for ring opening also indicate a strong kinetic preference for allyloxy radical formation over the formation of the (vinyloxy)methyl radical. The results of the present calculations on the aziridinylmethyl radical indicates that it kinetically prefers to ring open by cleavage of the C−N bond, but thermodynamically by cleavage of the C−C bond. The results of the calculations on the C2H4NO radical system indicate that ring...
Collective feature selection to identify crucial epistatic variants

Machine learning methods have gained popularity and practicality in identifying linear and non-linear effects of variants associated with complex disease/traits. Detection of epistatic interactions still remains a challenge due to the large number of features and relatively small sample size as input, thus leading to the so-called “short fat data” problem. The efficiency of machine learning methods can be increased by limiting the number of input features. Thus, it is very important to perform variable selection before searching for epistasis. Many methods have been evaluated and proposed to perform feature selection, but no single method works best in all scenarios. We demonstrate this by conducting two separate simulation analyses to evaluate the proposed collective feature selection approach. Through our simulation study we propose a collective feature selection approach to select features that are in the “union” of the best performing methods. We explored various parametric, non-parametric, and data mining approaches to perform feature selection. We choose our top performing methods to select the union of the resulting variables based on a user-defined percentage of variants selected from each method to take to downstream analysis. Our simulation analysis shows that non-parametric data mining approaches, such as MDR, may work best under one simulation criteria for the high effect size (penetrance) datasets, while non-parametric methods designed for feature selection, such as Ranger and Gradient boosting, work best under other simulation criteria. Thus, using a collective approach proves to be more beneficial for selecting variables with epistatic effects also in low effect size datasets and different genetic architectures. Following this, we applied our proposed collective feature selection approach to select the top 1% of variables to identify potential interacting variables associated with Body Mass Index (BMI) in ~ 44,000 samples obtained from Geisinger’s MyCode Community Health Initiative (on behalf of DiscovEHR collaboration). In this study, we were able to show that selecting variables using a collective feature selection approach could help in selecting true positive epistatic variables more frequently than applying any single method for feature selection via simulation studies. We were able to demonstrate the effectiveness of collective feature selection along with a comparison of many methods in our simulation analysis. We also applied our method to identify non-linear networks associated with obesity.
Aromatization of cyclohexenones with iodine/sodium alkoxide. A regioselective synthesis of 2-iodophenols

Abstract Aromatizations of a wide variety of easily accessible 2-cyclohexenone-4-carboxylates with iodine and sodium ethoxide give the corresponding 2-iodophenols in good yield and high regioselectivity.
Resolving Cytosolic Diffusive States in Bacteria by Single-Molecule Tracking

Abstract The trajectory of a single protein in the cytosol of a living cell contains information about its molecular interactions in its native environment. However, it has remained challenging to accurately resolve and characterize the diffusive states that can manifest in the cytosol using analytical approaches based on simplifying assumptions. Here, we show that multiple intracellular diffusive states can be successfully resolved if sufficient single-molecule trajectory information is available to generate well-sampled distributions of experimental measurements and if experimental biases are taken into account during data analysis. To address the inherent experimental biases in camera-based and MINFLUX-based single-molecule tracking, we use an empirical data analysis framework based on Monte Carlo simulations of confined Brownian motion. This framework is general and adaptable to arbitrary cell geometries and data acquisition parameters employed in two-dimensional or three-dimensional single-molecule tracking. We show that, in addition to determining the diffusion coefficients and populations of prevalent diffusive states, the timescales of diffusive state switching can be determined by stepwise increasing the time window of averaging over subsequent single-molecule displacements. Time-averaged diffusion analysis of single-molecule tracking data may thus provide quantitative insights into binding and unbinding reactions among rapidly diffusing molecules that are integral for cellular functions.
TOTAL SYNTHESIS OF A POTENT PROINFLAMMATORY 5-OXO-ETE AND ITS 6,7-DIHYDRO BIOTRANSFORMATION PRODUCT

The first total synthesis of a potent inflammatory mediator 5-oxo-6(E),8(Z),11(Z),14(Z)-eicosatetraenoic acid (5-oxo-ETE) 2 and its biotransformation product 6,7-dihydro-5-oxo-ETE 5 is reported. A convergent synthesis for the unstable title compounds is accomplished via two synthons, dithiolane aldehyde 13 and bisdienyl phosphonium bromide 19. The synthetic 5-oxo-ETE 2 and its 8,9-trans isomer 3 were used to unequivocally confirm the structure of the biologically derived mediators. In addition, using synthetic 6,7-dihydro-5-oxo-ETE 5 we have been able to identify in neutrophils the formation of 6,7-dihydro-5-oxo-ETE 5.
First quaternary A-Pb-Bi-Q (A = K, Rb, Cs; Q = S, Se) compounds: Synthesis, structure, and properties of α-and β-CsPbBi3Se6, APbBi3Se6, (A = K, Rb), and APbBi3S6 (A = Rb, Cs)

{alpha}-CsPbBi{sub 3}Se{sub 6} (I), {beta}-CsPbBi{sub 3}Se{sub 6} (II), RbPbBi{sub 3}Se{sub 6} (III), KPbBi{sub 3}Se{sub 6} (IV), CsPbBi{sub 3}S{sub 6} (V), and RbPbBi{sub 3}S{sub 6} (VI) were synthesized by the polychalcogenide flux method. {alpha}-CsPbBi{sub 3}Se{sub 6} was obtained at 720 C and crystallizes in the space group Pnma (No. 62) with a = 23.564(6) {angstrom}, b = 4.210(2) {angstrom}, c = 13.798(3) {angstrom} at room temperature. Final R/R{sub w} = 3.0/3.6%. In this compound, parallel NaCl-type Pb/Bi/Se columns with rectangularly shaped cross-sections are interconnected by edge sharing to build a 3-D tunnel framework with Cs atoms located inside the tunnels. The hexagonal plates of {beta}-CsPbBi{sub 3}Se{sub 6} were obtained at 400 C and crystallize in the space group P6{sub 3}/mmc (No. 194) with a = 4.213(2) {angstrom}, c = 25.22(1) {angstrom}, {gamma} = 120 at {minus}100 C. Final R/R{sub w} = 4.2/4.7%. APbBi{sub 3}Se{sub 6} (A = Rb, K) and APbBi{sub 3}S{sub 6} (A = Cs, Rb) are isostructural with {beta}-CsPbBi{sub 3}Se{sub 6} and their hexagonal cell parameters were obtained at room temperature. The structure is composed of negatively charged Bi{sub 2}Te{sub 3}-type bilayers separated by alkali metals, which are distributed over two different crystallographic sites. The alkali metal ions are more » loosely packed in the interlayer space making them mobile. Topotactic ion-exchange reactions of two compounds, {beta}-CsPbBi{sub 3}Se{sub 6} and RbPbBi{sub 3}Se{sub 6}, were examined with LiI and NaI in the solid state and in aqueous solution. Prolonged water contact of the hexagonal compounds leads to decomposition and leaching of alkali metal and Pb{sup 2+} ions. Electrical conductivity and thermopower measurements for single crystals of I, II, and III show n-type semiconductor behavior with 0.6, 0.3, and 0.3 S/cm and {minus}730, {minus}550, and {minus}560 {micro}V/K at room temperature, respectively. The optical band gaps of all compounds range from 0.27 to 0.89 eV. Thermal properties of the compounds are reported. « less
Multi-laminate annulus fibrosus repair scaffold with an interlamellar matrix enhances impact resistance, prevents herniation and assists in restoring spinal kinematics.

Abstract Focal defects in the annulus fibrosus (AF) of the intervertebral disc (IVD) arising from herniation have detrimental impacts on the IVD's mechanical function. Thus, biomimetic-based repair strategies must restore the mechanical integrity of the AF to help support and restore native spinal loading and motion. Accordingly, an annulus fibrosus repair patch (AFRP); a collagen-based multi-laminate scaffold with an angle-ply architecture has been previously developed, which demonstrates similar mechanical properties to native outer AF (oAF). To further enhance the mimetic nature of the AFRP, interlamellar (ILM) glycosaminoglycan (GAG) was incorporated into the scaffolds. The ability of the scaffolds to withstand simulated impact loading and resist herniation of native IVD tissue while contributing to the restoration of spinal kinematics were assessed separately. The results demonstrate that incorporation of a GAG-based ILM significantly increased (p
Kinetics and Mechanism of the Methyltrioxorhenium-Catalyzed Sulfoxidation of Thioketones and Sulfines

Kinetic studies have been carried out on the oxidation of thiobenzophenones and thiocamphor by hydrogen peroxide and on the second step in the sequence, oxidation of the resulting sulfines (Ar2CSO)...
Competition between ester and formyl groups for control of torquoselectivity in cyclobutene electrocyclic reactions

Abstract Methyl 3-formylcyclobutene-3-carboxylate was synthesized in five steps from commercially available cyclobutane-1,1-dicarboxylic acid. Thermolysis afforded methyl (2H)-pyrane-5-carboxylate, which was formed by electrocyclization of the formyl-in, ester-out product of ring opening. This confirms theoretical predictions.
A Random-Dot Kinematogram for Web-Based Vision Research

Web-based experiments using visual stimuli have become increasingly common in recent years, but many frequently-used stimuli in vision research have yet to be developed for online platforms. Here, we introduce the first open access random-dot kinematogram (RDK) for use in web browsers. This fully customizable RDK offers options to implement several different types of noise (random position, random walk, random direction) and parameters to control aperture shape, coherence level, the number of dots, and other features. We include links to commented JavaScript code for easy implementation in web-based experiments, as well as an example of how this stimulus can be integrated as a plugin with a JavaScript library for online studies (jsPsych).
Synthesis of 3-Oxoalkylphosphonates via the Conjugate Addition of Acylcuprates to Diethyl Vinylphosphonate

Acylcuprate reagents generated by the reaction of dialkyleyanocuprates with carbon monoxide at low temperature ({minus}110 C) readily react with diethyl vinylphosphonate to give 30oxoalkylphosphonates in good yields after hydrolysis. The reaction intermediates can also be trapped by allylic bromides to give 1-allyl-3-oxoalkylphosphonates in good yields.
Efficient syntheses of crispine A and harmicine by RH-catalyzed cyclohydrocarbonylation.

The first examples of Rh-catalyzed cyclohydrocarbonylation-bicyclization of N-allylic amides of arylacetic acids are reported. This novel carbonylative bicyclization process was successfully applie...
Sonogashira coupling and cyclization reactions on alumina: a route to aryl alkynes, 2-substituted-benzo[b]furans and 2-substituted-indoles

Abstract A solventless, microwave-enhanced Sonogashira coupling reaction of aromatic iodides with terminal alkynes on potassium fluoride doped alumina in the presence of palladium powder, cuprous iodide, and triphenylphosphine has been developed. The reaction can be utilized to prepare aryl alkynes in excellent yields. The coupling of o-iodophenol with terminal alkynes leads to the formation 2-substituted-benzo[b]furans. Whereas the coupling of o-iodoanilines with terminal alkynes generates indole products. An in situ desilylation reaction was also developed.
Vibrational Circular Dichroism: A New Tool for the Solution-State Determination of the Structure and Absolute Configuration of Chiral Natural Product Molecules:

Vibrational circular dichroism (VCD) has been used in recent years to determine the absolute configuration of a number of natural product chiral molecules. In this brief review, these applications ...
Syntheses of 5- and 6-[2,3]-dihydrobenzofuran β-amino acids

Abstract Efficient stereoselective syntheses of 5- and 6-[2,3]-dihydrobenzofuran β-amino acids are described. These 3-aryl β-amino acids are aspartic acid mimetics that are structurally related to known benzodioxole systems. In many cases, the benzodioxole can inhibit and induce cytochrome P-450; neither of these dihydrobenzofuran β-amino esters is a potent inhibitor of several human P-450 enzymes.
Convergent Synthesis of Fully Functionalized Ring C Allocolchicinoids. Benzannulation Approach

A novel convergent approach to fully functionalized ring C allocolchicinoids is developed which is based on the benzannulation reaction of Fischer carbene complexes with alkynes. The efficacy of this strategy was established with the conversion of bromide 1a (R1 = Me, R2 = H) to the biaryl phenol 3a (R = Me, RL = Pr, RS = H) via the carbene complex 2a. Bromide 1b (R1 = t-Bu, R2 = OMe) was then used for the analogous preparation of the diastereomeric allocolchicinoids 3b (R = Me, RL = Pr, RS = H).
Quantitative assessment of cell fate decision between autophagy and apoptosis

Autophagy and apoptosis are cellular processes that regulate cell survival and death, the former by eliminating dysfunctional components in the cell, the latter by programmed cell death. Stress signals can induce either process, and it is unclear how cells ‘assess’ cellular damage and make a ‘life’ or ‘death’ decision upon activating autophagy or apoptosis. A computational model of coupled apoptosis and autophagy is built here to analyze the underlying signaling and regulatory network dynamics. The model explains the experimentally observed differential deployment of autophagy and apoptosis in response to various stress signals. Autophagic response dominates at low-to-moderate stress; whereas the response shifts from autophagy (graded activation) to apoptosis (switch-like activation) with increasing stress intensity. The model reveals that cytoplasmic Ca2+ acts as a rheostat that fine-tunes autophagic and apoptotic responses. A G-protein signaling-mediated feedback loop maintains cytoplasmic Ca2+ level, which in turn governs autophagic response through an AMP-activated protein kinase (AMPK)-mediated feedforward loop. Ca2+/calmodulin-dependent kinase kinase β (CaMKKβ) emerges as a determinant of the competing roles of cytoplasmic Ca2+ in autophagy regulation. The study demonstrates that the proposed model can be advantageously used for interrogating cell regulation events and developing pharmacological strategies for modulating cell decisions.
Delivering on the Paris Promises? Review of the Paris Agreement’s Implementing Guidelines from a Human Rights Perspective

The adoption of the Paris Agreement in 2015 constituted an unprecedented step in state recognition of the importance of ensuring that state action on the climate is informed by human rights: for the first time a global environmental legal instrument referred explicitly to human rights. However, whether this provision will contribute to the shaping of climate policies depends significantly on the extent to which it is integrated into further guidance regarding the implementation of the Agreement. The adoption by states of guidance on most aspects of the Paris Agreement, at COP 24/CMA1.3, in December 2018, is a litmus test on whether the implementation of the Agreement is likely to reflect a higher level of integration of human rights concerns into climate governance. Having noted the absence of explicit reference to human rights in the guidelines, this article reviews key aspects of the guidelines from the perspective of principles related to human rights, such as public participation, gender equality, and respect for the rights and knowledge of indigenous peoples. This review includes an analysis of the final provisions in key chapters of the guidelines. It is informed by the positions put forward by countries throughout the drafting process as well as by the evolution of negotiating texts prior to the finalization of the guidelines. The review finds that COP 24/CMA1.3 failed, for the most part, to uphold the principles laid out in the preamble to the Paris Agreement, particularly in relation to human rights; the guidelines make only a few references to human-rights-related principles.
A Latent Source Model for Online Collaborative Filtering

Despite the prevalence of collaborative filtering in recommendation systems, there has been little theoretical development on why and how well it works, especially in the "online" setting, where items are recommended to users over time. We address this theoretical gap by introducing a model for online recommendation systems, cast item recommendation under the model as a learning problem, and analyze the performance of a cosine-similarity collaborative filtering method. In our model, each of n users either likes or dislikes each of m items. We assume there to be k types of users, and all the users of a given type share a common string of probabilities determining the chance of liking each item. At each time step, we recommend an item to each user, where a key distinction from related bandit literature is that once a user consumes an item (e.g., watches a movie), then that item cannot be recommended to the same user again. The goal is to maximize the number of likable items recommended to users over time. Our main result establishes that after nearly log(km) initial learning time steps, a simple collaborative filtering algorithm achieves essentially optimal performance without knowing k. The algorithm has an exploitation step that uses cosine similarity and two types of exploration steps, one to explore the space of items (standard in the literature) and the other to explore similarity between users (novel to this work).
Stable A(1)-homotopy and R-equivalence

We prove that the existence of a k-rational point can be detected by the stable A1-homotopy category of S1-spectra, or even a “rationalized” variant of this category.
A-CNN: Annularly Convolutional Neural Networks on Point Clouds

Analyzing the geometric and semantic properties of 3D point clouds through the deep networks is still challenging due to the irregularity and sparsity of samplings of their geometric structures. This paper presents a new method to define and compute convolution directly on 3D point clouds by the proposed annular convolution. This new convolution operator can better capture the local neighborhood geometry of each point by specifying the (regular and dilated) ring-shaped structures and directions in the computation. It can adapt to the geometric variability and scalability at the signal processing level. We apply it to the developed hierarchical neural networks for object classification, part segmentation, and semantic segmentation in large-scale scenes. The extensive experiments and comparisons demonstrate that our approach outperforms the state-of-the-art methods on a variety of standard benchmark datasets (e.g., ModelNet10, ModelNet40, ShapeNet-part, S3DIS, and ScanNet).
Learning Compact Neural Networks with Regularization

Proper regularization is critical for speeding up training, improving generalization performance, and learning compact models that are cost efficient. We propose and analyze regularized gradient descent algorithms for learning shallow neural networks. Our framework is general and covers weight-sharing (convolutional networks), sparsity (network pruning), and low-rank constraints among others. We first introduce covering dimension to quantify the complexity of the constraint set and provide insights on the generalization properties. Then, we show that proposed algorithms become well-behaved and local linear convergence occurs once the amount of data exceeds the covering dimension. Overall, our results demonstrate that near-optimal sample complexity is sufficient for efficient learning and illustrate how regularization can be beneficial to learn over-parameterized networks.
Variational information maximisation for intrinsically motivated reinforcement learning

The mutual information is a core statistical quantity that has applications in all areas of machine learning, whether this is in training of density models over multiple data modalities, in maximising the efficiency of noisy transmission channels, or when learning behaviour policies for exploration by artificial agents. Most learning algorithms that involve optimisation of the mutual information rely on the Blahut-Arimoto algorithm — an enumerative algorithm with exponential complexity that is not suitable for modern machine learning applications. This paper provides a new approach for scalable optimisation of the mutual information by merging techniques from variational inference and deep learning. We develop our approach by focusing on the problem of intrinsically-motivated learning, where the mutual information forms the definition of a well-known internal drive known as empowerment. Using a variational lower bound on the mutual information, combined with convolutional networks for handling visual input streams, we develop a stochastic optimisation algorithm that allows for scalable information maximisation and empowerment-based reasoning directly from pixels to actions.