Exploring the Role of 'Intermediaries' between Non-Operating Landowners and Tenant Farmers in Promoting Conservation on Rented Farmland.

Promoting conservation on rented farmland is a challenge for stakeholders working with non-operating landowners (NOLs) and tenant farmers (operators). We conducted an online survey to identify stakeholders who engage with NOLs, and understand how their positioning as 'intermediaries' could be leveraged to help bridge the NOL-operator communication gap. A majority of identified stakeholders/intermediaries worked in government agencies, university extension, law firms, or farm management companies. Intermediaries believed that NOLs trusted them for several conservation activities, however, they believed that NOLs were more influenced by operators than by intermediaries. The message that engaging in conservation can help preserve the farm for future generation was perceived to be influential in motivating NOLs. Our findings suggest the need for a holistic approach to engage NOLs by accounting for trust in and influence of intermediaries and operators, and the salience of conservation messages and messaging when promoting conservation behaviors on rented farmlands.

On Transannulation in Azaphosphatranes: Synthesis and Theoretical Analysis.

A combined synthetic-theoretical study has been undertaken to determine the factors that influence transannulation in azaphosphatranes. The commonly used proazaphosphatrane P(i-BuNCH2CH2)3N and several of its oxidized congeners are used as model systems. The haloazaphosphatranes of P(i-BuNCH2CH2)3N were synthesized, including a rare fluoroazaphopshatrane, and used as references for computational investigations. Comparisons of the experimental and theoretical observations highlight the flexibility observed in transannulated atranes and the potential for multiple local energetic minima depending on the identity of the equatorial substituents for a given azaphosphatrane. Theoretical calculations also identify the role of the ethylene linker in azaphosphatrane bonding, the influence of transannulation on P-electrophile interactions, and the contribution of electrostatic interactions to transannulation.

TeamSTEPPS Virtual Teams: Interactive Virtual Team Training and Practice for Health Professional Learners.

Medical errors because of communication failure are common in health care settings. Teamwork training, such as Team Strategies and Tools to Enhance Performance and Patient Safety (TeamSTEPPS), improves team performance and patient outcomes. Academic institutions seek high-quality, low-cost curricula for interprofessional education (IPE) to prepare learners for clinical experiences before and after graduation; however, most IPE curricula involve lectures, simple tabletop exercises, and in-person simulations and are not readily accessible to geographically distributed and asynchronously engaged learners. To address this need, interprofessional faculty from multiple institutions and specialties created a series of eight screen-based interactive virtual simulation cases featuring typical clinical situations, with the goal of preparing learners to provide safe and effective care in clinical teams. Virtual simulations permit flexible, asynchronous learning on the learner's schedule and allow educators an opportunity to identify gaps in knowledge and/or attitudes that can be addressed during class or forum discussions. In 2016, 1,128 unique users accessed the scenarios. As a result of such virtual activities, learner selection of the appropriate TeamSTEPPS tool increased with progression through the scenarios.

Enantioselective, Stereodivergent Hydroazidation and Hydroamination of Allenes Catalyzed by Acyclic Diaminocarbene (ADC) Gold(I) Complexes.

The gold-catalyzed enantioselective hydroazidation and hydroamination reactions of allenes are presented herein. ADC gold(I) catalysts derived from BINAM were critical for achieving high levels of enantioselectivity in both transformations. The sense of enantioinduction is reversed for the two different nucleophiles, allowing access to both enantiomers of the corresponding allylic amines using the same catalyst enantiomer.

Application of fundamental organometallic chemistry to the development of a gold-catalyzed synthesis of sulfinate derivatives.

The development of a gold(I)-catalyzed sulfination of aryl boronic acids is described. This transformation proceeds through an unprecedented mechanism which exploits the reactivity of gold(I)-heteroatom bonds to form sulfinate anions. Further in situ elaboration of the sulfinate intermediates leads to the corresponding sulfones and sulfonamides, two pharmacophores routinely encountered in drug discovery.

Comparative Analysis of the Donor Properties of Isomeric Pyrrolyl Phosphine Ligands.

Understanding the net donor and electronic properties of pyrrole-based phosphines is critical for guiding their use as ligands. In this study, we compare two isomeric 1- and 2-(diphenylphosphino)methylpyrroles (L1 and L2, respectively) to determine the degree to which N-(phosphino)pyrroles are distinct from aryl- and 2-pyrrolyl phosphines. Ruthenium, rhodium, platinum, and gold complexes as well as selenide derivatives of these ligands are examined using NMR and IR spectroscopy, X-ray crystallography, and cyclic voltammetry. Ligand L2 exhibits net donor properties similar to those of the o-tolyl analogue L3, while L1 shows attenuated electron donation ability. Additionally, a model nickel-catalyzed Kumada coupling reaction using these three ligands was investigated.

Synthesis of pyrrole-based PSiP pincer ligands and their palladium, rhodium, and platinum complexes.

The synthesis and coordination chemistry of a new class of silyl pincer ligand featuring pyrrole-based linkers is reported. The steric and electronic properties of these bis(phosphinopyrrole)methylsilane ligands were interrogated using their palladium, rhodium, and platinum complexes. The pyrrole-based linker attenuates the donor ability of the ligand relative to its reported 1,2-phenylene congener while maintaining a similar steric profile. Additionally, the silyl donor connected to the N-pyrrolyl groups exhibits a weaker trans influence than the analogous ligand featuring 1,2-phenylene linkers.

High-turnover supramolecular catalysis by a protected ruthenium(II) complex in aqueous solution.

The design of a supramolecular catalyst capable of high-turnover catalysis is reported. A ruthenium(II) catalyst is incorporated into a water-soluble supramolecular assembly, imparting the ability to catalyze allyl alcohol isomerization. The catalyst is protected from decomposition by sequestration inside the host but retains its catalytic activity with scope governed by confinement within the host. This host-guest complex is a uniquely active supramolecular catalyst, capable of >1000 turnovers.

Acetic acid aldol reactions in the presence of trimethylsilyl trifluoromethanesulfonate.

In the presence of TMSOTf and a trialkylamine base, acetic acid undergoes aldol addition to non-enolizable aldehydes under exceptionally mild conditions. Acidic workup yields the beta-hydroxy carboxylic acid. The reaction appears to proceed via a three-step, one-pot process, including in situ trimethylsilyl ester formation, bis-silyl ketene acetal formation, and TMSOTf-catalyzed Mukaiyama aldol addition. Independently synthesized TMSOAc also undergoes aldol additions under similar conditions.

Study and modular synthesis of unsymmetrical bis(phosphino)pyrrole ligands.

We report the facile and modular synthesis of unsymmetrical 1,2-bis(phosphino)pyrrole ligands and their coordination chemistry. These ligands offer a promising alternative to their 1,2-bis(phosphino)benzene congeners, retaining a similar steric profile with attenuated electron donation. Proof-of-principle application of a bis(phosphino)pyrrole ligand in a nickel-catalyzed C-N cross-coupling reaction under mild conditions is demonstrated.

Heuristic recurrent algorithms for photonic Ising machines.

The inability of conventional electronic architectures to efficiently solve large combinatorial problems motivates the development of novel computational hardware. There has been much effort toward developing application-specific hardware across many different fields of engineering, such as integrated circuits, memristors, and photonics. However, unleashing the potential of such architectures requires the development of algorithms which optimally exploit their fundamental properties. Here, we present the Photonic Recurrent Ising Sampler (PRIS), a heuristic method tailored for parallel architectures allowing fast and efficient sampling from distributions of arbitrary Ising problems. Since the PRIS relies on vector-to-fixed matrix multiplications, we suggest the implementation of the PRIS in photonic parallel networks, which realize these operations at an unprecedented speed. The PRIS provides sample solutions to the ground state of Ising models, by converging in probability to their associated Gibbs distribution. The PRIS also relies on intrinsic dynamic noise and eigenvalue dropout to find ground states more efficiently. Our work suggests speedups in heuristic methods via photonic implementations of the PRIS.

A mechanistic investigation of the photoinduced, copper-mediated cross-coupling of an aryl thiol with an aryl halide.

Photoinduced, copper-catalyzed cross-coupling can offer a complementary approach to thermal (non-photoinduced) methods for generating C-X (X = C, N, O, S, etc.) bonds. In this report, we describe the first detailed mechanistic investigation of one of the processes that we have developed, specifically, the (stoichiometric) coupling of a copper-thiolate with an aryl iodide. In particular, we focus on the chemistry of a discrete [CuI(SAr)2]- complex (Ar = 2,6-dimethylphenyl), applying a range of techniques, including ESI-MS, cyclic voltammetry, transient luminescence spectroscopy, optical spectroscopy, DFT calculations, Stern-Volmer analysis, EPR spectroscopy, actinometry, and reactivity studies. The available data are consistent with the viability of a pathway in which photoexcited [CuI(SAr)2]-* serves as an electron donor to an aryl iodide to afford an aryl radical, which then reacts in cage with the newly generated copper(II)-thiolate to furnish the cross-coupling product in a non-chain process.

Synthesis of Stable Gold(III) Pincer Complexes with Anionic Heteroatom Donors.

A series of gold(III) complexes supported by pyridine-based bis(amidate), bis(carboxylate), and bis(iminothiolate) substituents is reported. These compounds represent rare examples of pincer-ligated gold(III) centers with multiple anionic heteroaom donors. Reactivity and electrochemical studies demonstrate the stability of these compounds and the marked difference in reduction potentials with varying ligand scaffolds.

A brain-machine interface to navigate a mobile robot in a planar workspace: enabling humans to fly simulated aircraft with EEG.

This paper presents an interface for navigating a mobile robot that moves at a fixed speed in a planar workspace, with noisy binary inputs that are obtained asynchronously at low bit-rates from a human user through an electroencephalograph (EEG). The approach is to construct an ordered symbolic language for smooth planar curves and to use these curves as desired paths for a mobile robot. The underlying problem is then to design a communication protocol by which the user can, with vanishing error probability, specify a string in this language using a sequence of inputs. Such a protocol, provided by tools from information theory, relies on a human user's ability to compare smooth curves, just like they can compare strings of text. We demonstrate our interface by performing experiments in which twenty subjects fly a simulated aircraft at a fixed speed and altitude with input only from EEG. Experimental results show that the majority of subjects are able to specify desired paths despite a wide range of errors made in decoding EEG signals.

One-pot enol silane formation-Mukaiyama aldol-type addition to dimethyl acetals mediated by TMSOTf.

Various ketones, esters, amides, and thioesters add in high yield to dimethyl acetals in the presence of silyl trifluoromethanesulfonates and an amine base. Acetals derived from aryl, unsaturated, and aliphatic aldehydes are all effective substrates. The reaction proceeds in a single reaction flask, with no purification of the intermediate enol silane necessary.