cssi/SciSciGPT-SciSciNet huggingface dataset:
The Natural History of Coiled Cerebral Aneurysms Stratified by Modified Raymond-Roy Occlusion Classification.

Objective The natural history and long-term durability of Guglielmi detachable coil (GDC) embolization is still unknown. We hypothesize a stepwise decrease in durability of embolized cerebral aneurysms as stratified by the Modified Raymond-Roy Classification (MRRC). Methods First-time GDC-embolized cerebral aneurysms were retrospectively reviewed from 2004 to 2015. Loss of durability (LOD) was defined by change in aneurysm size or patency seen on serial radiographic follow-up. Kaplan-Meier survival analysis was performed to evaluate embolization durability. Multivariate Cox regression modeling was used to assess baseline aneurysm and patient characteristics for their effect on LOD. Results A total of 427 patients with 443 aneurysms met the inclusion criteria. Overall, 89 (21%) aneurysms met LOD criteria. Grade 1 aneurysms had statistically significantly greater durability than did all other MRRC grades. Grade 3b aneurysms had significantly worse durability than did all other aneurysm grades. There was no difference in durability between grade 2 and 3a aneurysms. Of aneurysms with LOD, 26 (29%) experienced worsening of MRRC grade. Thirty-five (24%) initial MRRC grade 2, 72 (45%) initial MRRC grade 3a, and 6 (22%) initial MRRC grade 3b aneurysms progressed to MRRC grade 1 without retreatment. In our multivariate analysis, only initial MRRC grade was statistically significantly associated with treatment durability (P Conclusions MRRC grade is independently associated with first-time GDC-embolized cerebral aneurysm durability. Achieving MRRC grade 1 occlusion outcome is significantly associated with greater long-term GDC durability. Although few aneurysms experience further growth and/or recanalization, most incompletely obliterated aneurysms tend to remain stable over time or even progress to occlusion. Grading scales such as the MRRC are useful for characterizing aneurysm occlusion but may lack sensitivity and specificity for characterizing changes in aneurysm morphology over time.
PseudoFuN: Deriving functional potentials of pseudogenes from integrative relationships with genes and microRNAs across 32 cancers.

Background Long thought "relics" of evolution, not until recently have pseudogenes been of medical interest regarding regulation in cancer. Often, these regulatory roles are a direct by-product of their close sequence homology to protein-coding genes. Novel pseudogene-gene (PGG) functional associations can be identified through the integration of biomedical data, such as sequence homology, functional pathways, gene expression, pseudogene expression, and microRNA expression. However, not all of the information has been integrated, and almost all previous pseudogene studies relied on 1:1 pseudogene-parent gene relationships without leveraging other homologous genes/pseudogenes. Results We produce PGG families that expand beyond the current 1:1 paradigm. First, we construct expansive PGG databases by (i) CUDAlign graphics processing unit (GPU) accelerated local alignment of all pseudogenes to gene families (totaling 1.6 billion individual local alignments and >40,000 GPU hours) and (ii) BLAST-based assignment of pseudogenes to gene families. Second, we create an open-source web application (PseudoFuN [Pseudogene Functional Networks]) to search for integrative functional relationships of sequence homology, microRNA expression, gene expression, pseudogene expression, and gene ontology. We produce four "flavors" of CUDAlign-based databases (>462,000,000 PGG pairwise alignments and 133,770 PGG families) that can be queried and downloaded using PseudoFuN. These databases are consistent with previous 1:1 PGG annotation and also are much more powerful including millions of de novo PGG associations. For example, we find multiple known (e.g., miR-20a-PTEN-PTENP1) and novel (e.g., miR-375-SOX15-PPP4R1L) microRNA-gene-pseudogene associations in prostate cancer. PseudoFuN provides a "one stop shop" for identifying and visualizing thousands of potential regulatory relationships related to pseudogenes in The Cancer Genome Atlas cancers. Conclusions Thousands of new PGG associations can be explored in the context of microRNA-gene-pseudogene co-expression and differential expression with a simple-to-use online tool by bioinformaticians and oncologists alike.
American Behavioral Scientist Special Issue: The Science and Imagination of Living Generously:

This special issue addresses the science and imagination of living generously. Generosity is investigated from multiple disciplinary approaches, across the seven articles included in the issue. The...
Childhood Trauma and Stressful Life Events Are Independently Associated with Sleep Disturbances in Adolescents

Adolescence is a critical developmental period associated with an increase in stress, the appearance of anxiety and depressive symptoms, and changes in sleep patterns. Even though the disruption of sleep patterns in stress and anxiety and depressive disorders is well known, the independent effects of childhood trauma and stressful life events on sleep patterns are less understood. We tested the independent effects of stress (childhood trauma and stressful life events) while controlling for anxiety and depression on adolescent sleep patterns. Seven hundred fifty-two adolescents (age 12-15 years) completed self-report questionnaires about childhood trauma, stressful life events, anxiety, and depression. Four sleep factors identifying movement during sleep, sleep regularity, sleep disturbances, and sleep pressure were extracted in the principal component analysis of sleep questions. Both childhood trauma and recent stressful life events were significantly associated with sleep disturbances before and after controlling for anxiety and depression.
Synthesis and biological activity of aromatic amino acid phosphoramidates of 5-fluoro-2'-deoxyuridine and 1-β-arabinofuranosylcytosine : Evidence of phosphoramidase activity

The amino acid phosphoramidate diesters of FUdR (2) and Ara-C (6), 5-fluoro-2'-deoxy-5'-uridyl N-(1-carbomethoxy-2-phenylethyl)phosphoramidate (5a), 5-fluoro-2'-deoxy-5'- uridyl N-(1-carbomethoxy-2-indolylethyl)phosphoramidate (5b), 1-beta-arabinofuranosylcytosine 5'-N-(1-carbomethoxy-2-phenylethyl) phosphoramidate (8a), and 1-beta-arabinofuranosylcytosine 5'-N-(1-carbomethoxy-2-indolylethyl)phosphoramidate (8b), were synthesized and tested for their antitumor activity against L1210 mouse lymphocytic leukemia cells and CCRF-CEM human T-cell lymphoblastic leukemia cells. Ara-C phosphoramidates 8a,b were found to be inactive at a concentration of 100 microM, while the FUdR conjugates 5a,b exhibited IC50 values within a range of 0.30-0.40 microM. Stability studies revealed that > 99% of the phosphoramidates remained intact after incubation for > 2 days in 20% calf or 20% human serum. Intracellular thymidylate synthase (TS) inhibition studies revealed that treatment of L1210 and CCRF-CEM cells with 5a or 5b resulted in significant inhibition of TS in intact and permeabilized cells, while treatment of L929 TK- cells with these compounds did not result in inhibition of TS activity in intact cells. However, permeabilization of L929 TK- cells enhanced the activity of 5a,b toward intracellular TS by 900- and 1500-fold, respectively. In addition, incubation of cell-free extracts of CEM cells with radiolabeled 5b resulted in the rapid production of FUdR 5'-monophosphate and a lag in the generation of FUdR. Consequently, it is proposed that the metabolism of the phosphoramidate diesters of FUdR in proliferating tissue proceeds through two separate enzymatic steps involving P-N bond cleavage by an unknown phosphoramidase followed by P-O bond cleavage by phosphatases such as 5'-nucleotidase.
The preparation and utility of bis(sulfinyl)imidoamidine ligands for the copper-catalyzed Diels-Alder reaction

The design and preparation of a novel class of ligands based on the sulfinyl imine functionality is described. In particular, an efficient and modular synthesis of bis(sulfinyl)imidoamidine (siam) ligands is reported. The versatility of the synthetic sequence is demonstrated by the preparation of various analogues to explore the effect of substitution about the ligand framework on catalytic activity. The utility of the siam ligands in asymmetric catalysis is demonstrated in the Cu(II)-catalyzed Diels-Alder reaction where highly enantio- and diastereoselective reactions are reported for a range of N-acyloxazolidinone dienophile and diene substrate combinations. Of particular note is the efficiency of these asymmetric catalysts for reactions involving challenging and relatively unreactive acyclic diene substrates. Finally, structural data are provided for several ligands as well as metal-ligand complexes.
Catalyzed Reformatsky Reactions with Ethyl Bromofluoroacetate for the Synthesis of α-Fluoro-β-hydroxy Acids

The presence of catalytic amounts of CeCl3 improves yields and simplifies procedure in the Reformatsky reactions of ethyl bromofluoroacetate with aldehydes and ketones to generate diastereomeric mixtures of α-fluoro-β-hydroxy esters, some of which can be separated by crystallization or column flash chromatography. Diastereomerically pure α-fluoro-β-hydroxy acids are obtained by mild alkaline hydrolysis of the resolved α-fluoro-β-hydroxy esters. Detailed NMR data of new α-fluoro-β-hydroxy esters and α-fluoro-β-hydroxy acids are also presented.
C2-chiral dinucleating ligands with a 3,6-disubstituted pyridazine core

Abstract Reaction of the 3,6-bis(tosyloxymethyl)pyridazine ( 1 ) with two equivalents of (1R-2S)-norephedrine or (1S-2R)-1-amino-2-indanol leads to the formation of C2-chiral dinucleating ligands containing a 3,6-disubstituted pyridazine core flanked by aminoalcohol pendant arms, namely 3,6-bis((1R-2S)-(2-hydroxy-1-methyl-2-phenyl-ethyl)aminomethyl)pyridazine ( 2 ) and 3,6-bis((1S-2R)-(2-hydroxy-indan-1-yl)aminomethyl)pyridazine ( 3 ). As shown by spectrometric titration experiments as well as ESI/MS, ligands 2 and 3 bind copper(II) cations to form dinuclear complexes.
A Silicon Tether Approach for Diastereocontrol in Radical Addition to Chiral Hydrazones

A radical carbon−carbon bond construction approach to chiral α-branched amines is presented. Stereocontrolled radical addition to chiral hydrazones can be achieved by virtue of conformational constraints imposed during cyclizations using a temporary silicon connection. Oxidative removal of the tether completes the hydroxymethylation process to afford anti-2-hydrazino-1,3-diols in good yield. The 1,2-induction increases with increasing A values of the appended groups, consistent with prediction by the Beckwith−Houk model for stereocontrol in 5-hexenyl radical cyclizations.
n-BuLi/LiCH2CN-Mediated One-Carbon Homologation of Aryl Epoxides into Conjugated Allyl Alcohols

A series of styrene oxides in the presence of a 1:1 mixture of n-butyllithium (n-BuLi) and lithioacetonitrile (LiCH2CN) in THF are converted into one-carbon homologated allyl alcohols in an unusual regioselective manner.
Independence between pre-mRNA splicing and DNA methylation in an isogenic minigene resource

Actively transcribed genes adopt a unique chromatin environment with characteristic patterns of enrichment. Within gene bodies, H3K36me3 and cytosine DNA methylation are elevated at exons of spliced genes and have been implicated in the regulation of pre-mRNA splicing. H3K36me3 is further responsive to splicing, wherein splicing inhibition led to a redistribution and general reduction over gene bodies. In contrast, little is known of the mechanisms supporting elevated DNA methylation at actively spliced genic locations. Recent evidence associating the de novo DNA methyltransferase Dnmt3b with H3K36me3-rich chromatin raises the possibility that genic DNA methylation is influenced by splicing-associated H3K36me3. Here, we report the generation of an isogenic resource to test the direct impact of splicing on chromatin. A panel of minigenes of varying splicing potential were integrated into a single FRT site for inducible expression. Profiling of H3K36me3 confirmed the established relationship to splicing, wherein levels were directly correlated with splicing efficiency. In contrast, DNA methylation was equivalently detected across the minigene panel, irrespective of splicing and H3K36me3 status. In addition to revealing a degree of independence between genic H3K36me3 and DNA methylation, these findings highlight the generated minigene panel as a flexible platform for the query of splicing-dependent chromatin modifications.
Persistence of Fusarium oxysporum f. sp. fragariae in Soil Through Asymptomatic Colonization of Rotation Crops

Asymptomatic plant colonization is hypothesized to enhance persistence of pathogenic forms of Fusarium oxysporum. However, a correlation between pathogen populations on living, asymptomatic plant tissues and soilborne populations after tillage has not been demonstrated. Living and dead tissues of broccoli, lettuce, spinach, wheat, cilantro, raspberry, and strawberry plants grown in soil infested with F. oxysporum f. sp. fragariae (the cause of Fusarium wilt of strawberry) were assayed to quantify the incidence of infection and extent of colonization by this pathogen. All crops could be infected by F. oxysporum f. sp. fragariae but the extent of colonization varied between plant species. Pathogen population densities on nonliving crown tissues incorporated into the soil matrix were typically greater than those observed on living tissues. Crop-dependent differences in the inoculum density of F. oxysporum f. sp. fragariae in soil were only observed after decomposition of crop residue. Forty-four weeks after plants were incorporated into the soil, F. oxysporum f. sp. fragariae soil population densities were positively correlated with population densities on plant tissue fragments recovered at the same time point. Results indicate that asymptomatic colonization can have a significant, long-term impact on soilborne populations of Fusarium wilt pathogens. Cultural practices such as crop rotation should be leveraged to favor pathogen population decline by planting hosts that do not support extensive population growth on living or decomposing tissues.
Porphyrins with exocyclic rings. Part 8. Synthesis of nitrogen-15 and carbon-13 labeled 2,3:7,8:12,13:17,18-tetrabutanoporphyrin†‡§

Nitrogen-15 labeled butyl 4,5,6,7-tetrahydro-2H-isoindoIe-1-carboxylate was prepared via butyl iso-cyanoacetate from 15N-glycine in an overall 46% yield. This bicyclic intermediate was converted into nitrogen-15 and carbon-13 labeled 2,3:7,8:12,13:17,18-tetrabutanoporphyrin, a useful model system for the sedimentary tetrahydrobenzoporphyrins.
Highly stereoselective synthesis of (E)- and (Z)-α-fluoro-α,β-unsaturated esters and (E)- and (Z)-α-fluoro-α,β-unsaturated amides from 1-bromo-1-fluoroalkenes via palladium-catalyzed carbonylation reactions

The highly stereoselective synthesis of (E)- and (Z)-α-fluoro-α,β-unsaturated esters and (E)- and (Z)-α-fluoro-α,β-unsaturated amides is described. 1-Bromo-1-fluoroalkenes (E/Z ≈ 1:1), which are readily available starting materials, have been found to isomerize to high E/Z ratios after storage at −20 °C for 1 week or by photolysis at 254 nm. Since the (E)-isomers have been found to react faster than the corresponding (Z)-isomers at room temperature in Pd(0)-catalyzed reactions, the palladium-catalyzed carboalkoxylation of high E/Z 1-bromo-1-fluoroalkenes lead to a high Z/E (Z/E ≥ 98:2) ratio of the α-fluoro-α,β-unsaturated esters. When 1-bromo-1-fluoroalkenes (E/Z ≈ 1:1) were reacted with HCOOH/NBu3/Pd(II)/DMF, the (E)-isomer was selectively reduced, and the remaining (Z)-1-bromo-1-fluoroalkenes were recovered in essentially pure isomeric form. The resulting mixture of (Z)-1-bromo-1-fluoroalkenes and the reduced products underwent similar palladium-catalyzed carboalkoxylation reactions at 70 °C, and the (...
Poly(ε-caprolactone) macroligands with β-diketonate binding sites: synthesis and coordination chemistry

Abstract Dibenzoylmethane (dbm) initiators with one and two alcohol sites were used to generate dbm end-functionalized and dbm-centered poly(e-caprolactone) macroligands (dbmPCL and dbmPCL2) with low polydispersities (∼1.1). Chelation of polymeric ligands to metal ions (Eu3+, Fe3+, Ni2+ and Cu2+) produced metal-centered star polymers, which were characterized by UV–vis and fluorescence spectroscopy, as well as gel permeation chromatography.
Towards the synthesis of epothilone A: Enantioselective preparation of the thiazole sidechain and macrocyclic ring closure

Abstract A synthetic approach to a new class of microtubule-stabilizing natural products is described which employs a macrocyclic olefination strategy to cyclize the 16-membered lactone ring. The C13C19 thiazole subunit of epothilone A and B is prepared in high enantioselectivity using a catalytic asymmetric allylation reaction.
Closely related rare-earth metal germanides RE2Li2Ge3 and RE3Li4Ge4 (RE = La-Nd, Sm): synthesis, crystal chemistry, and magnetic properties.

Reported are the syntheses, crystal structures, and magnetic susceptibilities of two series of closely related rare-earth metal–lithium germanides RE2Li2Ge3 and RE3Li4Ge4 (RE = La–Nd, Sm). All titl...
High-yield assembly of individual single-walled carbon nanotube tips for scanning probe microscopies

The structural and mechanical properties of single-walled carbon nanotubes (SWNTs) make them ideal tips for scanning probe microscopies such as atomic force microscopy (AFM). However, the ideal nanotube probe, which corresponds to an individual SWNT, has been difficult to produce in high yield. To overcome this difficulty, a straightforward and easily implemented method that enables very high-yield fabrication of individual SWNT probes has been developed. This new method is based upon the observation that microfabricated tips can “pick up” vertically aligned SWNTs grown from planar substrate surfaces. Substrates with isolated, vertically aligned SWNT are first prepared by chemical vapor deposition and then imaged with commercial microfabricated silicon AFM tips. The silicon tips pick up individual SWNTs from the substrate during imaging to create well-aligned SWNT probes. The SWNT tips have been etched using a procedure that allows variation of the nanotube length with 2 nm control. Studies of gold nanocl...
Evidence for Synclinal Transition State in the Reactions of Aromatic Aldehydes with α-(Alkoxy)allylstannanes

Abstract Unlike aliphatic aldehydes, aromatic aldehydes produce greater than 95% of syn-(Z) enol ether when treated with α-(alkoxy)allylstannanes in the presence of BF3·Et2O. However, in the presence of TiCl4, the reaction of p-chloro-o-methoxybenzaldehyde with α-(alkoxy)crotylstannane produced predominantly the syn-(E) isomer.
Copper-Catalyzed Cross-Couplings of Organometallic Reagents with and without Assistance from PN Ligands

In this article, recent developments of copper-catalyzed cross-couplings are discussed. Critical results that demonstrate the effectiveness of copper catalysts, ligated by P,N-ligands, for cross-coupling reactions are presented to showcase the potential emergence of copper as an alternative to palladium. The observation that the reaction of heteroaryl coupling partners also proceeds under ‘ligand-free’ conditions holds great promise for developing copper catalysis as a complementary system to palladium catalysis in areas in which palladium either performs unsatisfactorily or requires custom-designed ligands. 1 Introduction 2 Rationale for the Use of Hybrid Bidentate Ligands 3 Coupling with Organosilicon Reagents 4 Coupling with Organoboron Reagents 5 Coupling with Organoindium Reagents 6 General Catalytic Cycle 7 Conclusion and Perspectives
Solvent Effects on Proton Transfer Reactions: Benzoate Ion Promoted Deprotonation Reactions of Arylnitromethanes in Methanol Solution

Second-order rate constants and equilibrium constants have been determined for the benzoate ion promoted deprotonation reactions of (m-nitrophenyl)nitromethane, (p-nitrophenyl)nitromethane, and (3,5-dinitrophenyl)nitromethane in methanol solution. The pKa values for the arylnitromethanes in methanol are the following: pKa = 10.9, 10.5, and 9.86 for (m-nitrophenyl)nitromethane, (p-nitrophenyl)nitromethane, and (3,5-dinitrophenyl)nitromethane, respectively, relative to benzoic acid (pKa = 9.4). A Bronsted βB value of 0.50 and αCH value of 1.31 have been calculated for the 3,4-dimethylbenzoate, benzoate, m-bromobenzoate, and 3,4-dichlorobenzoate ion promoted reactions of (3,5-dinitrophenyl)nitromethane, and for the benzoate ion promoted reactions of (m-nitrophenyl)nitromethane, (p-nitrophenyl)nitromethane, and (3,5-dinitrophenyl)nitromethane, respectively. The log of the intrinsic rate constants for benzoate ion promoted deprotonations of (m-nitrophenyl)nitromethane, (p-nitrophenyl)nitromethane, and (3,5-di...
N,O-Bis(trifluoroacetyl)hydroxylamine as a useful electrophilic nitrogen source: catalytic synthesis of N-(trifluoroacetyl)sulfilimines.

In the presence of catalytic quantites of Cu(OTf)2 the novel hydroxamic acid anhydride salt functions competently in the trifluoroacetamidation of sulfides to afford N-(trifluoroacetyl)sulfilimines. The salient features of this salt include its ease of synthesis from the inexpensive, commercially available starting materials trifluoroacetic anhydride and hydroxylamine hydrochloride.
Linchpin construction of unsymmetrical 1,4-alkynediols

A one-pot preparation of unsymmetrical 1,4-alkynediols such as 2a by the coupling of trimethylsilylacetylene and two different aldehydes or ketones is reported. The dilithiated species 5 is generated by the sequential addition of the first aldehyde or ketone 1b to a solution of lithium trimethylsilylacetylide, followed by the addition of methyllithium, which removes the trimethylsilyl protecting group. Addition of the second aldehyde or ketone then leads to the unsymmetrical 1,4-alkynediol 2a.
Synthesis and antiviral evaluation of certain novel pyrazinoic acid C-nucleosides

Pyrazine (1,4-diazine) C-nucleosides constitute a rare class of nucleic acid analogues that has only recently been reported in the literature. As part of our ongoing investigation into the synthesis and reactivity of these compounds, we have developed an electrophilic esterification of a lithiated pyrazine C-nucleoside (1) to give, following deprotection, the versatile intermediate ethyl 3,5-dichloro-6-(beta-d-ribofuranosyl)pyrazine-2-carboxylate (4). This intermediate was subjected to a variety of reaction conditions to generate a series of pyrazinoic acid C-nucleosides. These compounds, along with 3, 5-dichloro-2-(beta-d-ribofuranosyl)pyrazine (2) and 4, were evaluated for antiviral activity and cytotoxicity. No significant activity was observed for compounds 2 and 5-9, but 4 was active against two herpes viruses and cytotoxic in the micromolar range.
Cleaving Carbon–Carbon Bonds by the Release of Trifluoroacetate to Remodel Molecules and Assemble Fluorinated Structures

Cleaving carbon–carbon bonds is a significant synthetic challenge. The release of trifluoroacetate presents a powerful force to break these strong bonds. Herein, a brief review of the role of the release of trifluoroacetate in remodeling organic molecules and synthesizing fluorinated compounds is presented.
PHYSICAL UNCLONEABLE FUNCTION HARDWARE KEYS UTILIZING KIRCHHOFF-LAW- JOHNSON-NOISE SECURE KEY EXCHANGE AND NOISE-BASED LOGIC

Weak physical uncloneable function (WPUF) encryption key means that the manufacturer of the hardware can clone the key but anybody else is unable to so that. Strong physical uncloneable function (SPUF) encryption key means that even the manufacturer of the hardware is unable to clone the key. In this paper, first we introduce a "ultra"-strong PUF with intrinsic dynamical randomness, which is not only not cloneable but it also gets renewed to an independent key (with fresh randomness) during each use via the unconditionally secure key exchange. The solution utilizes the Kirchhoff-law-Johnson-noise (KLJN) method for dynamical key renewal and a one-time-pad secure key for the challenge/response process. The secure key is stored in a flash memory on the chip to provide tamper-resistance and non-volatile storage with zero power requirements in standby mode. Simplified PUF keys are shown: a strong PUF utilizing KLJN protocol during the first run and noise-based logic (NBL) hyperspace vector string verification method for the challenge/response during the rest of its life or until it is re-initialized. Finally, the simplest PUF utilizes NBL without KLJN thus it can be cloned by the manufacturer but not by anybody else.
Siloles: Part 2: Silaindenes (Benzosiloles) and Silafluorenes (Dibenzosiloles): Synthesis, Characterization, and Applications

Abstract The preparation of benzannulated siloles including silaindenes (benzosiloles) and silafluorenes (dibenzosiloles) reported during the period 1996 through 2010 is reviewed. As is the case for nonannulated siloles, tolan and related systems were the precursors of choice in the traditional route to silaindenes, through formation of a dilithio reagent. More recently, transition metal-catalyzed reactions of various silyl-substituted dienes and ene-ynes have been introduced as is also the case for condensation of 2-silylphenylboronic acid with alkynes. Formation of ladder oligomers and polymers with ladder segments related to silaindene is included. The traditional route to silafluorenes involved starting with o , o ′-dibromobiphenyl followed by formation of the dilithio reagent and then quenching with chlorosilanes. Several extensions of this approach have been made through development of new biphenyl precursors with multiple halogen substituents that then have produced substituents at the benzo-positions of the silafluorene that are useful for further chemical elaboration of the basic core. The traditional route through dilithio reagents has been supplemented by new transition metal-catalyzed processes involving a variety of precursors in addition to a Friedel–Crafts route to silafluorenes. Reactions at both the silicon center and involving C–X substituents on the carbon framework are summarized. Compounds related to silafluorenes such as silicon-bridged benzene-heteroarenes and silicon-bridged bithiophenes that exhibit a commonality in the synthetic methods to silafluorenes are discussed. Silafluorenes and dithienosiloles have played a role in the formation of oligomers as well as homopolymers and copolymers. Silafluorenes and dithienosiloles have been employed in electronic devices particularly in photovoltaic cells, white light-emitting diodes and bulk heterojunction solar cells and field effect transistors. The characterization methods reported for monomers and polymers are tabulated as well as applications in device construction when reported.
Dihapto binding of aromatic molecules by π-basic transition metal complexes: development of alternatives to the {Os(NH3)5}2+ fragment

Abstract Dihapto-coordination of aromatic ligands by electron-rich transition metals can effectively dearomatize the bound aromatic molecule. The pentaammineosmium(II) system forms thermally stable η 2 -complexes with a variety of arenes and aromatic heterocycles, and has been used for a variety of organic transformations on the bound aromatic fragments. The systematic variation of isoelectronic rhenium(I) systems has provided the necessary electronic and steric characteristics needed for a less expensive, chiral alternative to the {Os(NH 3 ) 5 } 2+ system. The {TpRe(CO)(PMe 3 )} system has been shown to form stable dihapto complexes with furan, thiophene and naphthalene. Accordingly, the {TpRe(CO)(PMe 3 )} fragment and analogous {TpRe(CO)(L)} fragments represent the first class of asymmetric surrogates to the pentaammineosmium(II) system.
Surveillance of CKD epidemiology in the US - a joint analysis of NHANES and KEEP.

Chronic Kidney Disease (CKD), is highly prevalent in the United States. Epidemiological systems for surveillance of CKD rely on data that are based solely on the NHANES survey, which does not include many patients with the most severe and less frequent forms of CKD. We investigated the feasibility of estimating CKD prevalence from the large-scale community disease detection Kidney Early Evaluation and Program (KEEP, n = 127,149). We adopted methodologies from the field of web surveys to address the self-selection bias inherent in KEEP. Primary outcomes studied were CKD Stage 3–5 (estimated glomerular filtration rate [eGFR] <60 mL/min/1.73 m2, and CKD Stage 4-5 (eGFR <30 mL/min/1.73 m2). The unweighted prevalence of Stage 4-5 CKD was higher in KEEP (1.00%, 95%CI: 0.94–1.05%) than in NHANES (0.51%, 95% CI: 0.43–0.59%). Application of a selection model that used variables related to demographics, recruitment and socio-economic factors resulted in estimates similar to NHANES (0.55%, 95% CI: 0.50–0.60%). Weighted prevalence of Stages 3–5 CKD in KEEP was 6.45% (95% CI: 5.70–7.28%) compared to 6.73% (95% CI: 6.30–7.19%) for NHANES. Application of methodologies that address the self-selection bias in the KEEP program may allow the use of this large, geographically diverse dataset for CKD surveillance.
Entry into the bi-aryl moiety of the TMC-95 proteasome inhibitors via the Stille protocol

Abstract The synthesis of the bi-aryl moiety of the TMC-95 natural products has been achieved via a palladium-catalyzed Stille cross-coupling reaction of an aryl stannane tyrosine derivative and 7-iodoisatin.
High valent FeIV chemistry in sustainable oxidation catalysis

Abstract Recent research in oxidation catalysis has focused on employing first-row metals with a lower environmental impact than their traditional counterparts. Iron is particularly suited for this task since the discovery of isolable non-heme iron(IV) complexes over a decade ago. This Letter summarizes the developments in the last decade for oxidation of organic substrates that proceed through iron(IV) intermediates. Eight separate oxidation reactions are reviewed.
Mobile-app analysis and instrumentation techniques reimagined with DECREE

A large number of mobile-app analysis and instrumentation techniques have emerged in the past decade. However, those techniques' components are difficult to extract and reuse outside their original tools, their evaluation results are hard to reproduce, and the tools themselves are hard to compare. This paper introduces DECREE, an infrastructure intended to guide such techniques to be reproducible, practical, reusable, and easy to adopt in practice. DECREE allows researchers and developers to easily discover existing solutions to their needs, enables unbiased and reproducible evaluation, and supports easy construction and execution of replication studies. The paper describes DECREE's three modules and its potential to fundamentally alter how research is conducted in this area.
Sign-tracking behavior is difficult to extinguish and resistant to multiple cognitive enhancers

The attribution of incentive-motivational value to drug-related cues underlies relapse and craving in drug addiction. One method of addiction treatment, cue-exposure therapy, utilizes repeated presentations of drug-related cues in the absence of drug (i.e., extinction learning); however, its efficacy has been limited due to an incomplete understanding of extinction and relapse processes after cues have been imbued with incentive-motivational value. To investigate this, we used a Pavlovian conditioned approach procedure to screen for rats that attribute incentive-motivational value to reward-related cues (sign-trackers; STs) or those that do not (goal-trackers; GTs). In Experiment 1, rats underwent Pavlovian extinction followed by reinstatement and spontaneous recovery tests. For comparison, a separate group of rats underwent PCA training followed by operant conditioning, extinction, and tests of reinstatement and spontaneous recovery. In Experiment 2, three cognitive enhancers (sodium butyrate, D-cycloserine, and fibroblast growth factor 2) were administered following extinction training to facilitate extinction learning. STs but not GTs displayed enduring resistance to Pavlovian, but not operant, extinction and were more susceptible to spontaneous recovery. In addition, none of the cognitive enhancers tested affected extinction learning. These results expand our understanding of extinction learning by demonstrating that there is individual variation in extinction and relapse processes and highlight potential difficulties in applying extinction-based therapies to drug addiction treatment in the clinic.
Organizational Construction and Interdisciplinary Identity in a New Health Care Organization

The authors examine the organizational construction of an interdisciplinary brain care center via ethnographic observation of vision and mission-building meetings and semistructured interviews with...
Genome-wide CRISPR screens reveal genetic mediators of cereblon modulator toxicity in primary effusion lymphoma

Genome-wide CRISPR/Cas9 screens represent a powerful approach to studying mechanisms of drug action and resistance. Cereblon modulating agents (CMs) have recently emerged as candidates for therapeutic intervention in primary effusion lymphoma (PEL), a highly aggressive cancer caused by Kaposi's sarcoma-associated herpesvirus. CMs bind to cereblon (CRBN), the substrate receptor of the cullin-RING type E3 ubiquitin ligase CRL4CRBN, and thereby trigger the acquisition and proteasomal degradation of neosubstrates. Downstream mechanisms of CM toxicity are incompletely understood, however. To identify novel CM effectors and mechanisms of CM resistance, we performed positive selection CRISPR screens using 3 CMs with increasing toxicity in PEL: lenalidomide (LEN), pomalidomide (POM), and CC-122. Results identified several novel modulators of the activity of CRL4CRBN The number of genes whose inactivation confers resistance decreases with increasing CM efficacy. Only inactivation of CRBN conferred complete resistance to CC-122. Inactivation of the E2 ubiquitin conjugating enzyme UBE2G1 also conferred robust resistance against LEN and POM. Inactivation of additional genes, including the Nedd8-specific protease SENP8, conferred resistance to only LEN. SENP8 inactivation indirectly increased levels of unneddylated CUL4A/B, which limits CRL4CRBN activity in a dominant negative manner. Accordingly, sensitivity of SENP8-inactivated cells to LEN is restored by overexpression of CRBN. In sum, our screens identify several novel players in CRL4CRBN function and define pathways to CM resistance in PEL. These results provide rationale for increasing CM efficacy on patient relapse from a less-efficient CM. Identified genes could finally be developed as biomarkers to predict CM efficacy in PEL and other cancers.
Mitigating Overexposure in Viral Marketing

In traditional models for word-of-mouth recommendations and viral marketing, the objective function has generally been based on reaching as many people as possible. However, a number of studies have shown that the indiscriminate spread of a product by word-of-mouth can result in overexposure, reaching people who evaluate it negatively. This can lead to an effect in which the over-promotion of a product can produce negative reputational effects, by reaching a part of the audience that is not receptive to it. How should one make use of social influence when there is a risk of overexposure? In this paper, we develop and analyze a theoretical model for this process; we show how it captures a number of the qualitative phenomena associated with overexposure, and for the main formulation of our model, we provide a polynomial-time algorithm to find the optimal marketing strategy. We also present simulations of the model on real network topologies, quantifying the extent to which our optimal strategies outperform natural baselines.
Atomic Cross-Chain Swaps

An atomic cross-chain swap is a distributed coordination task where multiple parties exchange assets across multiple blockchains, for example, trading bitcoin for ether.An atomic swap protocol guarantees (1) if all parties conform to the protocol, then all swaps take place, (2) if some coalition deviates from the protocol, then no conforming party ends up worse off, and (3) no coalition has an incentive to deviate from the protocol.A cross-chain swap is modeled as a directed graph D, whose vertexes are parties and whose arcs are proposed asset transfers. For any pair (D, L), where D = (V,A) is a strongly-connected directed graph and L ⊂ V a feedback vertex set for D, we give an atomic cross-chain swap protocol for D, using a form of hashed timelock contracts, where the vertexes in L generate the hashlocked secrets. We show that no such protocol is possible if D is not strongly connected, or if D is strongly connected but L is not a feedback vertex set. The protocol has time complexityO(diam(D)) and space complexity (bits stored on all blockchains) O(|A|2).
Non-Parametric Sparse Additive Auto-Regressive Network Models

Consider a multi-variate time series ${(X_{t})}_{t=0}^{T}$ , where $X_{t} \in \mathbb {R}^{d}$ which may represent spike train responses for multiple neurons in a brain, crime event data across multiple regions, and many others. An important challenge associated with these time series models is to estimate an influence network between the $d$ variables, especially when $d$ is large, meaning we are in the high-dimensional setting . Prior work has focused on parametric vector auto-regressive models. However, parametric approaches are somewhat restrictive in practice. In this paper, we use the non-parametric sparse additive model (SpAM) framework to address this challenge. Using a combination of $\beta $ and $\phi $ -mixing properties of Markov chains and empirical process techniques for reproducing kernel Hilbert spaces (RKHSs), we provide upper bounds on mean-squared error in terms of the sparsity $s$ , the logarithm of the dimension $\log ~d$ , the number of time points $T$ , and the smoothness of the RKHSs. Our rates are sharp up to logarithm factors in many cases. We also provide numerical experiments that support our theoretical results and display the potential advantages of using our non-parametric SpAM framework for a Chicago crime data set.
Detecting and Correcting for Label Shift with Black Box Predictors

Faced with distribution shift between training and test set, we wish to detect and quantify the shift, and to correct our classifiers without test set labels. Motivated by medical diagnosis, where diseases (targets) cause symptoms (observations), we focus on label shift, where the label marginal $p(y)$ changes but the conditional $p(x| y)$ does not. We propose Black Box Shift Estimation (BBSE) to estimate the test distribution $p(y)$. BBSE exploits arbitrary black box predictors to reduce dimensionality prior to shift correction. While better predictors give tighter estimates, BBSE works even when predictors are biased, inaccurate, or uncalibrated, so long as their confusion matrices are invertible. We prove BBSE's consistency, bound its error, and introduce a statistical test that uses BBSE to detect shift. We also leverage BBSE to correct classifiers. Experiments demonstrate accurate estimates and improved prediction, even on high-dimensional datasets of natural images.
Small Dense Subgraphs of a Graph

Given a family ${\cal F}$ of graphs, and a positive integer $n$, the Turan number $ex(n,{\cal F})$ of ${\cal F}$ is the maximum number of edges in an $n$-vertex graph that does not contain any member of ${\cal F}$ as a subgraph. The order of a graph is the number of vertices in it. In this paper, we study the Turan number of the family of graphs with bounded order and high average degree. For every real $d\geq 2$ and positive integer $m\geq 2$, let ${\cal F}_{d,m}$ denote the family of graphs on at most $m$ vertices that have average degree at least $d$. It follows from a simple application of the probabilistic method that $ex(n,{\cal F}_{d,m})=\Omega(n^{2-\frac{2}{d}+\frac{2}{dm}})$. Verstraete [personal communications] asked if it is true that for each fixed $d$ there exists a function $\epsilon_d(m)$ that tends to $0$ as $m\to \infty$ such that $ex(n,{\cal F}_{d,m})=O(n^{2-\frac{2}{d}+\epsilon_d(m)})$. We answer Verstraete's question in the affirmative whenever $d$ is an integer, showing that $ex(n,{\c...
Learning Dictionaries for Named Entity Recognition using Minimal Supervision

This paper describes an approach for automatic construction of dictionaries for Named Entity Recognition (NER) using large amounts of unlabeled data and a few seed examples. We use Canonical Correlation Analysis (CCA) to obtain lower dimensional embeddings (representations) for candidate phrases and classify these phrases using a small number of labeled examples. Our method achieves 16.5% and 11.3% F-1 score improvement over co-training on disease and virus NER respectively. We also show that by adding candidate phrase embeddings as features in a sequence tagger gives better performance compared to using word embeddings.
Braid groups and discrete diffeomorphisms of the punctured disk

We show that the group cohomology of the diffeomorphisms of the disk with n punctures has the cohomology of the braid group of n strands as the summand. As an application of this method, we also prove that there is no cohomological obstruction to lifting the “standard” embedding $$\mathrm {Br}_{2g+2}\hookrightarrow \mathrm {Mod}_{g,2}$$ to a group homomorphism between diffeomorphism groups.
Learning to Detect Multiple Photographic Defects

In this paper, we introduce the problem of simultaneously detecting multiple photographic defects. We aim at detecting the existence, severity, and potential locations of common photographic defects related to color, noise, blur and composition. The automatic detection of such defects could be used to provide users with suggestions for how to improve photos without the need to laboriously try various correction methods. Defect detection could also help users select photos of higher quality while filtering out those with severe defects in photo curation and summarization. To investigate this problem, we collected a large-scale dataset of user annotations on seven common photographic defects, which allows us to evaluate algorithms by measuring their consistency with human judgments. Our new dataset enables us to formulate the problem as a multi-task learning problem and train a multi-column deep convolutional neural network (CNN) to simultaneously predict the severity of all the defects. Unlike some existing single-defect estimation methods that rely on low-level statistics and may fail in many cases on natural photographs, our model is able to understand image contents and quality at a higher level. As a result, in our experiments, we show that our model has predictions with much higher consistency with human judgments than low-level methods as well as several baseline CNN models. Our model also performs better than an average human from our user study.
A representation on the labeled rooted forests

ABSTRACTWe consider the conjugation action of symmetric group on the semigroup of all partial functions and develop a machinery to investigate character formulas and multiplicities. By interpreting these objects in terms of labeled rooted forests, we give a characterization of the labeled rooted trees whose Sn orbit afford the sign representation. Applications to rook theory are offered.
Tensor-multinomial sums of ideals: Primary decompositions and persistence of associated primes

Given a polynomial ring $C$ over a field and proper ideals $I$ and $J$ whose generating sets involve disjoint variables, we determine how to embed the associated primes of each power of $I+J$ into a collection of primes described in terms of the associated primes of select powers of $I$ and of $J$. We record two applications. First, in case the field is algebraically closed, we construct primary decompositions for powers of $I+J$ from primary decompositions for powers of $I$ and $J$. Separately, we attack the persistence problem for associated primes of powers of an ideal in case one of $I$ or $J$ is a non-zero normal ideal.
Post‐selection point and interval estimation of signal sizes in Gaussian samples

We tackle the problem of the estimation of a vector of means from a single vector-valued observation $y$. Whereas previous work reduces the size of the estimates for the largest (absolute) sample elements via shrinkage (like James-Stein) or biases estimated via empirical Bayes methodology, we take a novel approach. We adapt recent developments by Lee et al (2013) in post selection inference for the Lasso to the orthogonal setting, where sample elements have different underlying signal sizes. This is exactly the setup encountered when estimating many means. It is shown that other selection procedures, like selecting the $K$ largest (absolute) sample elements and the Benjamini-Hochberg procedure, can be cast into their framework, allowing us to leverage their results. Point and interval estimates for signal sizes are proposed. These seem to perform quite well against competitors, both recent and more tenured. Furthermore, we prove an upper bound to the worst case risk of our estimator, when combined with the Benjamini-Hochberg procedure, and show that it is within a constant multiple of the minimax risk over a rich set of parameter spaces meant to evoke sparsity.
Balanced $k$-Center Clustering When $k$ Is A Constant

The problem of constrained $k$-center clustering has attracted significant attention in the past decades. In this paper, we study balanced $k$-center cluster where the size of each cluster is constrained by the given lower and upper bounds. The problem is motivated by the applications in processing and analyzing large-scale data in high dimension. We provide a simple nearly linear time $4$-approximation algorithm when the number of clusters $k$ is assumed to be a constant. Comparing with existing method, our algorithm improves the approximation ratio and significantly reduces the time complexity. Moreover, our result can be easily extended to any metric space.
The distribution of integers in a totally real cubic field

Abstract Hecke studies the distribution of fractional parts of quadratic irrationals with Fourier expansion of Dirichlet series. This method is generalized by Behnke and Ash–Friedberg, to study the distribution of the number of totally positive integers of given trace in a general totally real number field of any degree. When the field is cubic, we show that the asymptotic behavior of a weighted Diophantine sum is related to the structure of the unit group. The main term can be expressed in terms of Grossencharacter L -functions.
Understanding outcome bias

Abstract Disentangling effort and luck is critical when evaluating outcomes. In a principal-agent experiment, we demonstrate that principals' judgments of agents are biased by luck, despite perfectly observable effort. This erodes the power of incentives to stimulate effort. We explore two potential solutions to this “outcome bias”–information control, and outsourcing judgment to independent third parties. Both are ineffective. When principals control information about luck, they do not avoid it. When agents control information, they manipulate principals' outcome bias to minimize punishments. We also find that even independent third parties exhibit outcome bias. These findings suggest that outcome bias cannot be driven solely by disappointment nor distributional preferences. Instead, we hypothesize that luck directly affects principals' inference about agent type even though effort is observed. We elicit the beliefs of third parties and principals and find that lucky agents are believed to be harder workers than identical, unlucky agents.
Modeling quantum cascade lasers: Coupled electron and phonon transport far from equilibrium and across disparate spatial scales

Quantum cascade lasers (QCLs) are high-power coherent light sources in the midinfrared and terahertz parts of the electromagnetic spectrum. They are devices in which the electronic and lattice systems are far from equilibrium, strongly coupled to one another, and the problem bridges disparate spatial scales. We present our ongoing work on the multiphysics and multiscale simulation of far-from-equilibrium transport of charge and heat in midinfrared QCLs.