Directed Rh(I)-Catalyzed Asymmetric Hydroboration of Prochiral 1-Arylcycloprop-2-ene-1-carboxylic Acid Derivatives

This is the peer reviewed version of the following article: A. Edwards, M. Rubina, M. Rubin, Chem. Eur. J. 2018, 24, 1394., which has been published in final form at http://doi.org/10.1002/chem.201704443. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.A full account on rhodium-catalyzed asymmetric, directed hydroboration of functionalized prochiral cyclopropenes affording enantiomerically enriched cyclopropylboronates is reported. The scope and limitations of two alternate directing groups, ester and carboxamide, are evaluated. It was found that hydroboration of esters appeared to be more sensitive to substitution in the aromatic ring of the substrates. Specifically, ortho-halogens were detrimental for diastereo- and enantioselectivity, possibly because of additional coordination with rhodium. In contrast, more Lewis-basic amide directing groups allowed for stronger chelation to the transition metal, leading to consistently high diastereo- and enantioselectivity in hydroboration across a broader range of substrates

Coastal Conservation Lands Update (2005)

The Complex Systems Research Center (CSRC) at the University of New Hampshire has developed, implemented, and coordinated the GRANIT GIS clearinghouse since its inception in the mid 1980’s. One of the primary data sets maintained by CSRC and served through the clearinghouse is the Conservation and Protected Lands Data Layer. This data set contains a digital record of parcels of land of two or more acres that are mostly undeveloped and are protected from future development. Smaller parcels that adjoin previously mapped parcels or represent unique features, such as a bog or state-owned boat ramp, may also be included in this data layer. Through the GRANIT Conservation Lands Data Layer Update project, data on current protected lands were collected, reviewed, and processed for 48 communities in seacoast NH, including the 42 towns within the NH Estuaries Project area. GRANIT staff contacted each community’s conservation commission, as well as all quasi-public entities and land trusts active in the region, to solicit updates and additions to the data set. Concurrently, staff from the NH Office of Energy and Planning contacted the state and federal agencies that manage property in the seacoast to request comparable information. Through this collaborative process, 166 new tracts covering over 6,000 acres were added to the database. In addition, information on 122 existing tracts was modified to incorporate the reported corrections

GRANIT Conservation Lands Data Layer Update

The Complex Systems Research Center (CSRC) at the University of New Hampshire has developed, implemented, and coordinated the GRANIT GIS clearinghouse since its inception in the mid 1980’s. One of the primary data sets maintained by CSRC and served through the clearinghouse is the GRANIT Conservation and Protected Lands Data Layer. This data set contains a digital record of parcels of land of two or more acres that are mostly undeveloped and are protected from future development. Smaller parcels that adjoin previously mapped parcels or represent unique features, such as a bog or state-owned boat ramp, may also be included in the data layer. Through the GRANIT Conservation Lands Data Layer Update project, current protected lands data were collected, reviewed, and processed for the 47-community area within the NH Estuaries Project study area. GRANIT staff contacted each community’s conservation commission to solicit updates. Concurrently, staff from the Society for the Protection of NH Forests contacted the active land trusts in the region. Through this collaborative process, 235 tracts covering 6,997 acres were added to the database. In addition to new tracts, information for existing tracts was modified to incorporate any reported corrections. The resulting, updated data set is available to municipal decision-makers, the land trust community, and the general public through the GRANIT web site (www.granit.sr.unh.edu) and the GRANIT Conservation Lands Viewer (www.granitmap.sr.unh.edu)

Sustained eruptions on Enceladus explained by turbulent dissipation in tiger stripes

Spacecraft observations suggest that the plumes of Saturn's moon Enceladus draw water from a subsurface ocean, but the sustainability of conduits linking ocean and surface is not understood. Observations show sustained (though tidally modulated) fissure eruptions throughout each orbit, and since the 2005 discovery of the plumes. Peak plume flux lags peak tidal extension by $\sim$1 radian, suggestive of resonance. Here we show that a model of the tiger stripes as tidally-flexed slots that puncture the ice shell can simultaneously explain the persistence of the eruptions through the tidal cycle, the phase lag, and the total power output of the tiger stripe terrain, while suggesting that the eruptions are maintained over geological timescales. The delay associated with flushing and refilling of \emph{O}(1) m-wide slots with ocean water causes erupted flux to lag tidal forcing and helps to buttress slots against closure, while tidally pumped in-slot flow leads to heating and mechanical disruption that staves off slot freeze-out. Much narrower and much wider slots cannot be sustained. In the presence of long-lived slots, the 10$^6$-yr average power output of the tiger stripes is buffered by a feedback between ice melt-back and subsidence to \emph{O}(10$^{10}$) W, which is similar to the observed power output, suggesting long-term stability. Turbulent dissipation makes testable predictions for the final flybys of Enceladus by the \emph{Cassini} spacecraft. Our model shows how open connections to an ocean can be reconciled with, and sustain, long-lived eruptions. Turbulent dissipation in long-lived slots helps maintain the ocean against freezing, maintains access by future Enceladus missions to ocean materials, and is plausibly the major energy source for tiger stripe activity

Magnetic properties of the spin-1 two-dimensional J1−J3J_1-J_3 Heisenberg model on a triangular lattice

Motivated by the recent experiment in NiGa$_2$S$_4$, the spin-1 Heisenberg model on a triangular lattice with the ferromagnetic nearest- and antiferromagnetic third-nearest-neighbor exchange interactions, $J_1 = -(1-p)J$ and $J_3 = pJ, J > 0$, is studied in the range of the parameter $0 \leq p \leq 1$. Mori's projection operator technique is used as a method, which retains the rotation symmetry of spin components and does not anticipate any magnetic ordering. For zero temperature several phase transitions are observed. At $p \approx 0.2$ the ground state is transformed from the ferromagnetic order into a disordered state, which in its turn is changed to an antiferromagnetic long-range ordered state with the incommensurate ordering vector at $p \approx 0.31$. With growing $p$ the ordering vector moves along the line to the commensurate point $Q_c = (2 \pi /3, 0)$, which is reached at $p = 1$. The final state with the antiferromagnetic long-range order can be conceived as four interpenetrating sublattices with the $120\deg$ spin structure on each of them. Obtained results offer a satisfactory explanation for the experimental data in NiGa$_2$S$_4$.Comment: 2 pages, 3 figure

Self-similar slip pulses during rate-and-state earthquake nucleation

For a wide range of conditions, earthquake nucleation zones on rate- and state-dependent faults that obey either of the popular state evolution laws expand as they accelerate. Under the “slip” evolution law, which experiments show to be the more relevant law for nucleation, this expansion takes the form of a unidirectional slip pulse. In numerical simulations these pulses often tend to approach, with varying degrees of robustness, one of a few styles of self-similar behavior. Here we obtain an approximate self-similar solution that accurately describes slip pulses growing into regions initially sliding at steady state. In this solution the length scale over which slip speeds are significant continually decreases, being inversely proportional to the logarithm of the maximum slip speed V_(max), while the total slip remains constant. This slip is close to D_c(1−a/b)^(−1), where D_c is the characteristic slip scale for state evolution and a and b are the parameters that determine the sensitivity of the frictional strength to changes in slip rate and state. The pulse has a “distance to instability” as well as a “time to instability,” with the remaining propagation distance being proportional to (1−a/b)^(−2) [ln(V_(max)Θ_(bg)/D_c)]^(−1), where Θ_(bg) is the background state into which the pulse propagates. This solution provides a reasonable estimate of the total slip for pulses growing into regions that depart modestly from steady state

Internationalizing Humanities Education through Globally Networked Learning

This Level 2 Internationalizing Humanities Education through Globally Networked Learning Project will test and implement models that will assist humanities faculty to internationalize their classes by using available Internet-based tools to create a cross-cultural curriculum. Faculty will be trained to use learning management software and socio software tools to generate collaborative assignments that challenge students to negotiate and build shared learning cultures online. The project?s goal is to demonstrate that any humanities faculty member can teach a course in a globally networked learning environment if given the appropriate technological, pedagogical and intercultural support. A blog-based process journal will be used to track the challenges faced and lessons-learned during the implementation of humanities courses in Medieval Literature, Art History, and Drama Studies that will conducted with foreign partners in Russia, Ghana, and French Canada