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As agencies shift from single-species management to ecosystem-based fisheries management, ecosystem models are gaining interest for understanding species dynamics in relation to oceanographic and ecological processes and human marine uses. However, information on community structure or distribution of many species that occupy deep (>30 m) waters is largely unavailable. We amassed a total of 24 686 fish observations of 523 species/taxa for the 30−410 m depth areas surrounding the main Hawaiian Islands (MHI). We also obtained estimates of geomorphological variables, including substrate type, slope, rugosity, and ridge-like features. Using these 2 data sources, we (1) identified distinct fish communities along the 30−410 m depth gradient, and (2) generated relative biomass maps for fish functional groups. We showed that the mesophotic zone ranges between 30 and 129 m, with a fish faunal break at 60 m. Beyond this zone, 4 subphotic zones were identified: upper rariphotic (130−169 m), mid-rariphotic (170−239 m), lower rariphotic (240−319 m), and upper bathyal (320−410 m). We assigned fish species to functional groups partly based on identified depth ranges and fitted general additive models (GAMs) integrating geomorphological covariates to the functional group relative biomass estimates to determine the environmental variables that best predict the probability of encounter and relative biomass of each fish functional group. Finally, GAM predictions were employed to map functional group relative biomass distributions. These distribution maps showed a high relative biomass of many groups in the center of the MHI chain. This study contributes to a better understanding of fish community structure around the MHI and will inform ecosystem model parameterization.

Coral reefs worldwide face unprecedented cumulative anthropogenic effects of interacting local human pressures, global climate change and distal social processes. Reefs are also bound by the natural biophysical environment within which they exist. In this context, a key challenge for effective management is understanding how anthropogenic and biophysical conditions interact to drive distinct coral reef configurations. Here, we use machine learning to conduct explanatory predictions on reef ecosystems defined by both fish and benthic communities. Drawing on the most spatially extensive dataset available across the Hawaiian archipelago-20 anthropogenic and biophysical predictors over 620 survey sites-we model the occurrence of four distinct reef regimes and provide a novel approach to quantify the relative influence of human and environmental variables in shaping reef ecosystems. Our findings highlight the nuances of what underpins different coral reef regimes, the overwhelming importance of biophysical predictors and how a reef's natural setting may either expand or narrow the opportunity space for management interventions. The methods developed through this study can help inform reef practitioners and hold promises for replication across a broad range of ecosystems. © 2019 The Author(s)

Coral reefs worldwide face an uncertain future with many reefs reported to transition from being dominated by corals to macroalgae. However, given the complexity and diversity of the ecosystem, research on how regimes vary spatially and temporally is needed. Reef regimes are most often characterised by their benthic components; however, complex dynamics are associated with losses and gains in both fish and benthic assemblages. To capture this complexity, we synthesised 3,345 surveys from Hawai‘i to define reef regimes in terms of both fish and benthic assemblages. Model-based clustering revealed five distinct regimes that varied ecologically, and were spatially heterogeneous by island, depth and exposure. We identified a regime characteristic of a degraded state with low coral cover and fish biomass, one that had low coral but high fish biomass, as well as three other regimes that varied significantly in their ecology but were previously considered a single coral dominated regime. Analyses of time series data reflected complex system dynamics, with multiple transitions among regimes that were a function of both local and global stressors. Coupling fish and benthic communities into reef regimes to capture complex dynamics holds promise for monitoring reef change and guiding ecosystem-based management of coral reefs. © 2018, The Author(s).

Reactions of silanes with transition-metal complexes are of interest because their relevance to Si-H bond activation, the structural properties of polyhydrides, and catalytic hydrosilylation reactions. This work presents the results derived from reactions of arylsilanes Ph2SiH2 and PhSiH3 with OsH3Cl(PPh3)3 (1). Reaction of 1 with 1 equiv or excess Ph2SiH2 affords OsH3(SiClPh2)(PPh3)3 (2) or OsH4(SiClPh2)(SiHPh2)(PPh3)2 (3), respectively. These silyl complexes are formed via the oxidative addition of Si-H bonds and H/Cl exchange via silylene intermediates. Similarly, reaction of 1 with excess PhSiH3 produced the analogous bis(silyl) complex OsH4(SiClHPh)(SiH2Ph)(PPh3)2 (4). The bis(silyl) complexes are dodecahedral tetrahydride complexes containing weak Si···H interactions. The complex 3 reacts with PPh3 and CH3CN to selectively eliminate Ph2SiH2. Computational studies show that the preference for reductive eliminations from 3 follows the order Ph2SiH2 > H2 > Ph2SiHCl > Ph2HSi-SiClPh2. © 2017 American Chemical Society.

Introduction: A model of general practitioner (GP) and pharmacist collaboration in primary care may be an effective strategy to reduce medication-related problems and provide better support to patients after discharge. The aim of this study is to investigate whether a model of structured pharmacist and GP care reduces hospital readmissions in high-risk patients. Methods and analysis: This protocol details a stepped-wedge, cluster-randomised trial that will recruit participants over 9 months with a 12-month follow-up. There will be 14 clusters each representing a different general practice medical centre. A total of 2240 participants will be recruited from hospital who attend an enrolled medical centre, take five or more long-term medicines or whose reason for admission was related to heart failure or chronic obstructive pulmonary disease. The intervention is a multifaceted service, involving a pharmacist integrated into a medical centre to assist patients after hospitalisation. Participants will meet with the practice pharmacist and their GP after discharge to review and reconcile their medicines and discuss changes made in hospital. The pharmacist will follow-up with the participant and liaise with other health professionals involved in the participant's care. The control will be usual care, which usually involves a patient self-organising a visit to their GP after hospital discharge. The primary outcome is the rate of unplanned, all-cause hospital readmissions over 12 months, which will be analysed using a mixed effects Poisson regression model with a random effect for cluster and a fixed effect to account for any temporal trend. A cost analysis will be undertaken to compare the healthcare costs associated with the intervention to those of usual care. Ethics and dissemination: The study has received ethical approval (HREC/16/QRBW/410). The study findings will be disseminated through peer-reviewed publications, conferences and reports to key stakeholders.Copyright

High product yield of highly crystalline layered M xV 3O 8 compounds was obtained under hydrothermal conditions from the V 2O 5-Zn(OAc) 2·2H 2O-alkali metal salt-H 2O system at significantly lower reaction temperature than previously reported in neutral media for x = 1 and M = K +, Rb +, and Cs +, and in basic media for x = 2 and M = K +. Unreacted Zn(OAc) 2 may act as a catalyst and/or HOAc/OAc-acts as a buffer in obtaining monopotassium salts while enMe used to adjust pH can also act as a reducing agent in producing the dipotassium salt. A new layered dipotassium zinc pyrovanadate compound, K 2ZnV 2O 7, was formed when twice the stoichiometric ratio of the zinc salt was used. Single crystal X-ray diffraction shows the zinc compound to crystallize in the tetragonal space group P4 2/mnm (No. 136) with a = 8.3478(16) Å, c = 11.297(3) Å, V = 787.2(3) Å 3, and thus to be isomorphous with K 2MgV 2O 7. The pentagonal-motif layer structure of K 2ZnV 2O 7 is similar to that of K 2(VO)V 2O 7, but the unit cell parameters differ with approximate doubling of the c axial length when replacing the square-pyramidal VO 5 units of the [(V 4+O)V 5+ 2O 7] n 2n- layer with distorted ZnO 4 tetrahedra.

Four C(8),C(12)-diastereoisomers, (8S,12S)-isoandrographolide (1), (8S,12R)-isoandrographolide (2), (8R,12R)-isoandrographolide (3), and (8R,12S)-isoandrographolide (4) were isolated from the aerial parts of Andrographis paniculata. The structures of the new compounds 1-3 were established on the basis of the spectroscopic data including UV, IR, NMR, HR-ESI-MS, and X-ray diffraction analysis. Copyright © 2012 Verlag Helvetica Chimica Acta AG, Zürich, Switzerland.

Novel fluorescent organic soft porous crystals have been designed and prepared based on a multi-substituted silole bearing 1-phenyl-2,2-dicyanoethene moieties (molecule 8). 8 exhibited a series of emission colors, ranging from yellow to dark red with an over 70 nm shift of emission maximum. Molecule 8 also showed the ability to reversibly switch between different solid states, and a typical mechanofluorochromism was observed by cyclic operation of the grinding-heating-cooling processes. In addition, two single crystals (O and R) were successfully obtained in proper conditions, and the crystallographic data indicated that crystal O and R had reasonable hollow structures, inside which different solvent molecules were selectively encapsulated. More importantly, we have presented a proof-of-concept example of the strategy for the designation of organic soft porous crystals with a conjugated fluorophore and demonstrated the successful achievement of softness, porosity and crystallization ability. This design strategy is instructive to design and construct organic soft porous crystals with other conjugated building blocks and develop novel smart and stimuli-responsive photo/electronic materials.

The treatment of [Ru(LOEt)(N)Cl2] (1; L OEt- = [Co(η5-C5H 5){P(O)(OEt)2}3]-) with Et 3SiH affords [Ru(LOEt)Cl2(NH3)] (2), whereas that with [Ru(LOEt)(H)(CO)(PPh3)] (3) gives the dinuclear imido complex [(LOEt)Cl2Ru(μ-NH)Ru(CO) (PPh3)(LOEt)] (4). The imido group in 4 binds to the two ruthenium atoms unsymmetrically with Ru-N distances of 1.818(6) and 1.952(6) Å. The reaction between 1 and 3 at 25 °C in a toluene solution is first order in both complexes with a second-order rate constant determined to be (7.2 ± 0.4) × 10-5 M-1 s-1. © 2011 American Chemical Society.

Treatment of [Ru(CHR)Cl2(PCy3)2] (Cy = cyclohexyl) with Tl[N(Pr2iPO)2] and AgL OEt (LOEt- = [CpCo{P(O)(OEt)2} 3]-) afforded the Ru carbene complexes [Ru(CHPh)(PCy 3)Cl{N(Pr2iPO)2}] (1) and [L OEtRu(CHR)(PCy3)Cl] (2), respectively. Chloride abstraction of complex 2 with TlPF6 in MeCN afforded [L OEtRu(CHPh)(PCy3)(MeCN)][PF6] (3). Complexes 1 and 2 are capable of catalyzing ring-closing metathesis of diethyl 1,2-diallylmalonate. The crystal structure of complex 2 has been determined. © 2011 Published by Elsevier B.V.

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An inorganic-organic hybrid vanadate complex, Zn2(en)V 2O7 (en = ethylenediamine) has been hydrothermally synthesized and characterized by single-crystal X-ray crystallography, TG analysis, IR spectroscopy, and elemental analysis. The title compound crystallizes in the monoclinic space group P21 with a = 7.0885(7), b = 8.6040(9), c = 8.1869(8) Å, β = 112.224(2)° and V = 462.22(8) Å3, T = 298±2 K and R1[I>2σ(I)] = 0.0291 for 2170 observed reflections. The structure consists of undulating sheets constructed from helical chains that share Zn coordination centers with repeating units propagated into a helix by the two-fold screw axes at 0, y, 1/2 and pillared with alternating VO4 tetrahedra to generate a 3D chiral network. Neighboring helices are interconnected by μ2-O bridges to form the three-dimensional network. The strength of the network is reinforced by hydrogen bonding. TG analysis shows thermal stability of the network up to 283 °C. © 2008 Trans Tech Publications, Switzerland.

Two new aluminophosphates [ImH][AlP2O8H2·2H2O] 1 and 2[ImH][Al3P4O16H] 2 have been synthesized solvothermally at 160°C. Both compounds represent totally new structure types for the already extensive [AlP2O8] and [Al3P4O16] families. Compound 1 has a simple, puckered 2-D sheet structure containing Al4P48-membered rings and octahedral Al centers which are hydrated bytransaqua ligands. It is monoclinic, space groupC2/c,a=21.854(4),b=7.188(2),c=6.990(2) Å,β=103.77(2)°,V=1063.5(5) Å. Single crystal structure analysis gaveR=0.038,Rw=0.040 for 943 reflection intensities. Compound 2 has a complex layer structure which contains double 6MR subunits, the building blocks of many 3-D ALPOs, and has 5-coordinate as well as 4-coordinate aluminum. Single crystal structure analysis of 2 indicated the triclinic system, space groupP-1,a=8.940(2),b=9.360(2),c=11.721(2) Å,α=97.10(2)°,β=95.10(2)°,γ=91.91(2)°,V=968. 4(3) Å. Refinement gaveR=0.044,Rw=0.040 for 1613 unique observed reflections. © 1998 Academic Press.

Saccharide materials are potential candidates for frequency conversion applications. In addition to being chiral, which ensures crystallization in a space group necessary for three-wave mixing processes, they generally possess useful physical and optical properties. We have examined the powder second harmonic generation efficiencies of both saturated saccharides and sugars with simple polar π-functionalities. Powder efficiencies of up to 5 times that of sucrose were observed for simple saturated sugars, whereas values of 18 times sucrose (or 0.45 x urea) were observed for unsaturated saccharide derivatives. We have noted that for both classes of material, there is a tendency for more efficient nonlinear compounds to reside in a monoclinic rather than an orthorhombic space group. We have also noted that there appears to be a correlation between the phase-matching potential and the crystal symmetry. In addition, two promising saccharide materials have been identified for frequency conversion applications, based on their powder second-harmonic generation efficiencies, their phase-matching capabilities, and their UV transparency. © 1993 American Chemical Society.

Electron-excitation cross sections are reported for the 3s 2S→3p 2P(h,k) resonance transition in Mg+ at energies from threshold (4.43 eV) to approximately 9 times threshold (40.0 eV). The electron-energy-loss merged-beams technique used in these measurements is described in detail. In addition, the method of separating contributions of the elastically scattered (Coulomb) and the inelastically scattered electrons in the present Mg+ case and previously reported Zn+ results [Phys. Rev. Lett. 67, 30 (1991)] is described. Comparisons in the experimental energy range are made for Mg+ with the two five-state close-coupling theoretical calculations carried out herein, and with other published close-coupling, distorted-wave, and semiempirical calculations. The present Mg+ cross sections and Zn+ cross sections from earlier measurements are tabulated.

Inclusion complexation of organometallics with thiourea has been found to be an effective mechanism for controlling bulk nonlinear optical properties by inducing molecular dipolar alignment. Structures of the thiourea inclusion compounds with (benzene) Cr(CO)3 and (1,3-cyclohexadiene)Fe(CO)3 have been achieved. These materials generate second-harmonic radiation when exposed to the 1.06 μm output of a Nd-YAG laser.