State capacity is a core concept in political science research, and it is widely recognized that state institutions exert considerable influence on outcomes such as economic development, civil ...conflict, democratic consolidation, and international security. Yet researchers across these fields of inquiry face common problems involved in conceptualizing and measuring state capacity. In this article, we examine these conceptual issues, identify three core dimensions of state capacity, and develop the expectation that they are mutually supporting and interlinked. We then use Bayesian latent variable analysis to estimate state capacity at the conjunction of indicators related to these dimensions. We find strong interrelationships between the three dimensions and produce a new, general-purpose measure of state capacity with demonstrated validity for use in a wide range of empirical inquiries. It is hoped that this project will provide effective guidance and tools for researchers studying the causes and consequences of state capacity.
A cobalt catalyst has been developed for the acceptorless dehydrogenation of alcohols and applied to synthesize imines from alcohols and amines. Deuterium labeling studies suggest that the reaction ...proceeds by an initial reversible alcohol dehydrogenation step involving a cobalt hydride intermediate.
Recent advances in laser absorption and shock tube methodologies for studies of combustion chemistry are reviewed. First the principles of shock tube operation are discussed, and then an overview of ...shock tube diagnostic methods and experiments is covered. Recent shock tube developments include the use of driver inserts to counteract the small pressure gradient seen in conventional reflected shock wave experiments and the use of a constrained-reaction-volume strategy to enable the implementation of near-constant-pressure gasdynamic test conditions during energetic processes. Recent laser absorption developments include the use of a CO2 laser absorption sensor to accurately monitor temperature during shock wave experiments, the use of multi-wavelength laser absorption strategies to simultaneously monitor multiple species time-histories, and the used of isotopic labeling strategies to identify individual reaction sites during the measurement of elementary reaction rate constants. The improved ability to accurately constrain the test conditions in shock tube experiments, combined with non-intrusive, species-sensitive and quantitative laser absorption diagnostics, is enabling experimenters to provide a new generation of high-quality experimental kinetics targets for combustion chemistry model validation and refinement. The paper concludes with a brief discussion of newly emerging laser-diagnostic techniques and a summary of future research directions.
This work began as part of a biomass conversion catalysis project with UC Santa Barbara funded by the first NSF Chemical Bonding Center, CATSB. Recognizing that catalytic aerobic oxidation of diol ...C–C bonds could potentially be used to break down lignocellulose, we began to synthesize oxovanadium complexes and explore their fundamental reactivity. Of course there were theories regarding the oxidation mechanism, but our mechanistic studies soon revealed a number of surprises of the type that keep all chemists coming back to the bench! We realized that these reactions were also exciting in that they actually used the oxygen-on-every-carbon property of biomass-derived molecules to control the selectivity of the oxidation. When we found that these oxovanadium complexes tended to convert sugars predominantly to formic acid and carbon dioxide, we replaced one of the OH groups with an ether and entered the dark world of lignin chemistry. In this Account, we summarize results from our collaboration and from our individual labs. In particular, we show that oxidation selectivity (C–C vs C–O bond cleavage) of lignin models using air and vanadium complexes depends on the ancillary ligands, the reaction solvent, and the substrate structure (i.e., phenolic vs non-phenolic). Selected vanadium complexes in the presence of added base serve as effective alcohol oxidation catalysts via a novel base-assisted dehydrogenation pathway. In contrast, copper catalysts effect direct C–C bond cleavage of these lignin models, presumably through a radical pathway. The most active vanadium catalyst exhibits unique activity for the depolymerization of organosolv lignin. After Weckhuysen’s excellent 2010 review on lignin valorization, the number of catalysis studies and approaches on both lignin models and extracts has expanded rapidly. Today we are seeing new start-ups and lignin production facilities sprouting up across the globe as we all work to prove wrong the old pulp and paper chemist’s adage: you can make anything from lignin except money!
We prospectively compared health care worker-collected nasopharyngeal swabs (NPS) to self-collected anterior nasal swabs (ANS) and straight saliva for the diagnosis of coronavirus disease 2019 ...(COVID-19) in 354 patients. The percent positive agreement between NPS and ANS or saliva was 86.3% (95% confidence interval CI, 76.7 to 92.9%) and 93.8% (95% CI, 86.0 to 97.9%), respectively. The percent negative agreement was 99.6% (95% CI, 98.0 to 100.0%) for NPS versus ANS and 97.8% (95% CI, 95.3 to 99.2%) for NPS versus saliva. More cases were detected by the use of NPS (
= 80) and saliva (
= 81) than by the use of ANS (
= 70), but no single specimen type detected all severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections.
To understand which factors affect how willing people are to share their personal information to combat the Covid-19 pandemic, and compare them to factors that affect other public health behaviors. ...We analyze data from three pre-registered online experiments conducted over eight months during the Covid-19 pandemic in the United States (April 3 2020 -November 25, 2020). Our primary analysis tests whether support for data sharing and intention to practice protective behavior increase in response to relationship-centered messages about prosociality, disease spread, and financial hardship. We then conduct a secondary correlational analysis to compare the demographic and attitudinal factors associated with willingness to share data, protective behavior, and intent to get vaccinated. Our sample (N = 650) is representative to socio-demographic characteristics of the U.S. population. We find the altruistic condition increased respondents' willingness to share data. In our correlational analysis, we find interactive effects of political ID and socio-demographic traits on likelihood to share data. In contrast, we found health behavior was most strongly associated with political ID, and intent to vaccinate was more associated with socio-demographic traits. Our findings suggest that some public health messaging, even when it is not about data sharing or privacy, may increase public willingness to share data. We also find the role of socio-demographic factors in moderating the effect of political party ID varies by public health behavior.
The Nicoya OpenSPR is a benchtop surface plasmon resonance (SPR) instrument. As with other optical biosensor instruments, it is suitable for the label-free interaction analysis of a diverse set of ...biomolecules, including proteins, peptides, antibodies, nucleic acids, lipids, viruses, and hormones/cytokines. Supported assays include affinity/kinetics characterization, concentration analysis, yes/no assessment of binding, competition studies, and epitope mapping. OpenSPR exploits localized SPR detection in a benchtop platform and can be connected with an autosampler (XT) to perform automated analysis over an extended time period. In this review article, we provide a comprehensive survey of the 200 peer-reviewed papers published between 2016 and 2022 that use the OpenSPR platform. We highlight the range of biomolecular analytes and interactions that have been investigated using the platform, provide an overview on the most common applications for the instrument, and point out some representative research that highlights the flexibility and utility of the instrument.
The serology-based methods routinely used in forensic casework for the identification of biological fluids are costly in terms of time and sample and have varying degrees of sensitivity and ...specificity. Recently, the use of a molecular genetics-based approach using messenger RNA (mRNA) profiling has been proposed to supplant conventional methods for body fluid identification. However, the size of the amplification products used in these mRNA assays (∼ 200–300 nt) might not be ideal for use with degraded or compromised samples frequently encountered in forensic casework. Recently, there has been an explosion of interest in a novel class of small noncoding RNAs, microRNAs (miRNAs, ∼20–25 bases in length), with numerous published studies reporting that some miRNAs are expressed in a tissue-specific manner. In this article, we provide the first comprehensive evaluation of miRNA expression in dried, forensically relevant biological fluids—blood, semen, saliva, vaginal secretions, and menstrual blood—in an attempt to identify putative body fluid-specific miRNAs. Most of the 452 human miRNAs tested (∼67% of the known miRNA
ome) were either expressed in multiple body fluids or not expressed at all. Nevertheless, we have identified a panel of nine miRNAs—miR451, miR16, miR135b, miR10b, miR658, miR205, miR124a, miR372, and miR412—that are differentially expressed to such a degree as to permit the identification of the body fluid origin of forensic biological stains using as little as 50
pg of total RNA. The miRNA-based body fluid identification assays were highly specific because the miRNA expression profile for each body fluid was different from that obtained from 21 human tissues. The results of this study provide an initial indication that miRNA profiling may provide a promising alternative approach to body fluid identification for forensic casework.
Cobalt(II) alkyl complexes of aliphatic PNP pincer ligands have been synthesized and characterized. The cationic cobalt(II) alkyl complex (PNHPCy)Co(CH2SiMe3)BArF 4 (4) (PNHPCy = ...bis(2-dicyclohexylphosphino)ethylamine) is an active precatalyst for the hydrogenation of olefins and ketones and the acceptorless dehydrogenation of alcohols. To elucidate the possible involvement of the N–H group on the pincer ligand in the catalysis via a metal–ligand cooperative interaction, the reactivities of 4 and (PNMePCy)Co(CH2SiMe3)BArF 4 (7) were compared. Complex 7 was found to be an active precatalyst for the hydrogenation of olefins. In contrast, no catalytic activity was observed using 7 as a precatalyst for the hydrogenation of acetophenone under mild conditions. For the acceptorless dehydrogenation of 1-phenylethanol, complex 7 displayed similar activity to complex 4, affording acetophenone in high yield. When the acceptorless dehydrogenation of 1-phenylethanol with precatalyst 4 was monitored by NMR spectroscopy, the formation of the cobalt(III) acetylphenyl hydride complex (PNHPCy)CoIII(κ2-O,C-C6H4C(O)CH3)(H)BArF 4 (13) was detected. Isolated complex 13 was found to be an effective catalyst for the acceptorless dehydrogenation of alcohols, implicating 13 as a catalyst resting state during the alcohol dehydrogenation reaction. Complex 13 catalyzed the hydrogenation of styrene but showed no catalytic activity for the room temperature hydrogenation of acetophenone. These results support the involvement of metal–ligand cooperativity in the room temperature hydrogenation of ketones but not the hydrogenation of olefins or the acceptorless dehydrogenation of alcohols. Mechanisms consistent with these observations are presented for the cobalt-catalyzed hydrogenation of olefins and ketones and the acceptorless dehydrogenation of alcohols.
We propose and test an alternative approach to modeling high-temperature combustion chemistry of multicomponent real fuels. The hybrid chemistry (HyChem) approach decouples fuel pyrolysis from the ...oxidation of fuel pyrolysis products. The pyrolysis (or oxidative pyrolysis) process is modeled by seven lumped reaction steps in which the stoichiometric and reaction rate coefficients are derived from experiments. The oxidation process is described by detailed chemistry of foundational hydrocarbon fuels. We present results obtained for three conventional jet fuels and two rocket fuels as examples. Modeling results demonstrate that HyChem models are capable of predicting a wide range of combustion properties, including ignition delay times, laminar flame speeds, and non-premixed flame extinction strain rates of all five fuels. Sensitivity analysis shows that for conventional, petroleum-derived real fuels, the uncertainties in the experimental measurements of C2H4 and CH4 impact model predictions to an extent, but the largest influence of the model predictability stems from the uncertainties of the foundational fuel chemistry model used (USC Mech II). In addition, we introduce an approach in the realm of the HyChem approach to address the need to predict the negative-temperature coefficient (NTC) behaviors of jet fuels, in which the CH2O speciation history is proposed to be a viable NTC-activity marker for model development. Finally, the paper shows that the HyChem model can be reduced to about 30 species in size to enable turbulent combustion modeling of real fuels with a testable chemistry model.
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