bluuebunny/crossref_metadata_2025_split huggingface dataset:
Recent Advances in Catalytic Asymmetric Decarboxylative Addition Reactions
Authors: Wang Zu‐Li 
Published: August 2013

AbstractThis review examines recent advances in asymmetric catalytic decarboxylative addition reactions which have become a powerful method to form CC and CX bond using relatively cheap and stable carboxylic compounds. In these reactions, new CC or CX bonds are formed with extrusion of carbon dioxide (CO2). Asymmetric decarboxylative addition reactions have become alternatives to traditional addition reactions. Various asymmetric reactions between carboxylic acids and unsaturated compounds are summarized. The challenges and opportunities of these reactions are discussed.magnified image
Silver‐Promoted Benzannulations of Siloxyalkynes with Pyridinium and Isoquinolinium Salts
Authors: Cabrera‐Pardo Jaime R. , Chai David I. , Kozmin Sergey A. 
Published: August 2013

AbstractWe describe the development of efficient benzannulations of siloxyalkynes with pyridinium and isoquinolinium salts. Such reactions are successfully promoted by a stoichiometric amount of silver(I) benzolate under mild reaction conditions. This process proceeds via a formal inverse‐electron demand Diels–Alder reaction, followed by fragmentation of the initially produced bicyclic adducts to deliver a range of synthetically useful phenols and naphthols.magnified image
Local people see and care most? Severe depletion of inshore fisheries and its consequences for Māori communities in New Zealand
Authors: Mccarthy Alaric , Hepburn Chris , Scott Nigel , Schweikert Katja , Turner Rachel , Moller Henrik 
Published: August 2013

ABSTRACTOverfishing has the potential to adversely affect the ecological stability, economic value, social and spiritual integrity of a given area. Of these contexts, relatively little emphasis in literature is placed on the social and cultural consequences of overfishing and marine biodiversity loss.New Zealand's fisheries management system is regarded as one of the best in the world. But is this ‘success’ reflected at the local community scale? This study uses the knowledge of 100 participants from different stakeholder groups including Māori, New Zealand's indigenous peoples, and investigates local perception of the state of inshore fisheries stocks.Quantitative methods were used to assess the relative significance of important seafood species among different groups, while qualitative analysis highlighted main stakeholder concerns. A common consensus among all participants emerged; access to important inshore seafood species had become more difficult during the course of their lifetime with marked declines occurring from the 1970s onwards. Even where food species are present, they are typically harder to obtain, take longer to harvest and/or require expensive gear.Five species of marine invertebrates, three finfish species and one seabird were identified as having considerable worth to stakeholders. Of these, quantitative analysis revealed that pāua (abalone), tuna (eel) and tītī (muttonbird) were of particular significance to Māori stakeholders. Māori discussed pāua almost twice as much as non‐Māori, despite pāua ranking as the most significant species among both ethnic groups. Furthermore, Māori associated the depletion of pāua with a loss of cultural identity, hospitality, tradition, practices, emotional and spiritual connection to their environment. As such, in this paper pāua is defined as a ‘cultural keystone species’, whereby the removal of such a species jeopardizes cultural integrity.This paper serves as a case study bringing to light the disparity between an internationally acclaimed fisheries management strategy and the concerns of local stakeholders. Copyright © 2013 John Wiley & Sons, Ltd.
Hydrogen‐Bond Cooperative Effects in Small Cyclic Water Clusters as Revealed by the Interacting Quantum Atoms Approach
Authors: Guevara‐Vela José Manuel , Chávez‐Calvillo Rodrigo , García‐Revilla Marco , Hernández‐Trujillo Jesús , Christiansen Ove , Francisco Evelio , Martín Pendás Ángel , Rocha‐Rinza Tomás 
Published: August 2013

AbstractThe cooperative effects of hydrogen bonding in small water clusters (H2O)n(n=3–6) have been studied by using the partition of the electronic energy in accordance with the interacting quantum atoms (IQA) approach. The IQA energy splitting is complemented by a topological analysis of the electron density (ρ(r)) compliant with the quantum theory of atoms‐in‐molecules (QTAIM) and the calculation of electrostatic interactions by using one‐ and two‐electron integrals, thereby avoiding convergence issues inherent to a multipolar expansion. The results show that the cooperative effects of hydrogen bonding in small water clusters arise from a compromise between: 1) the deformation energy (i.e., the energy necessary to modify the electron density and the configuration of the nuclei of the isolated water molecules to those within the water clusters), and 2) the interaction energy (Eint) of these contorted molecules in (H2O)n. Whereas the magnitude of both deformation and interaction energies is enhanced as water molecules are added to the system, the augmentation of the latter becomes dominant when the size of the cluster is increased. In addition, the electrostatic, classic, and exchange components ofEintfor a pair of water molecules in the cluster (H2O)n−1become more attractive when a new H2O unit is incorporated to generate the system (H2O)nwith the last‐mentioned contribution being consistently the most important part ofEintthroughout the hydrogen bonds under consideration. This is opposed to the traditional view, which regards hydrogen bonding in water as an electrostatically driven interaction. Overall, the trends of the delocalization indices,δ(Ω,Ω′), the QTAIM atomic charges, the topology ofρ(r), and the IQA results altogether show how polarization, charge transfer, electrostatics, and covalency contribute to the cooperative effects of hydrogen bonding in small water clusters. It is our hope that the analysis presented in this paper could offer insight into the different intra‐ and intermolecular interactions present in hydrogen‐bonded systems.
Photoreaction of rac‐Leucine in Ice by Circularly Polarized Synchrotron Radiation: Temperature‐Induced Mechanism Switching from Norrish Type II to Deamination
Authors: Nishino Hideo , Hosaka Masahito , Katoh Masahiro , Inoue Yoshihisa 
Published: August 2013

AbstractThe delivery of extraterrestrial organics to primitive Earth is considered to have triggered the origin and subsequent evolution of life. Indeed, enantiomerically enriched amino acids of nonterrestrial origin have been found in carbonaceous meteorites, and enantioselective photodecomposition by circularly polarized light (CPL) in outer space has been proposed to have played some role in the initial enantiomeric bias. To experimentally examine this possibility and elucidate the photoreaction mechanisms, we have studied the photolysis of racemic leucine (rac‐Leu) in acidic and neutral ice/water media at 21–298 K with left‐ and right‐CPL in an attempt to detect enantiomerically enriched D‐ and L‐Leu, respectively. Comprehensive product analyses revealed that the CPL‐induced deracemization of Leu proceeds in both acidic and neutral ice matrices even at 21 K, and that the main mechanism switches from Norrish‐type II γ‐hydrogen abstraction to SNi deamination on lowering the temperature. The potential role of the CPL‐induced photodecomposition of amino acids as a source of the enantiomer imbalance in meteorites is discussed.
Probability Theory of Random Polygons from the Quaternionic Viewpoint
Authors: Cantarella Jason , Deguchi Tetsuo , Shonkwiler Clayton 
Published: August 2013

We build a new probability measure on closed space and plane polygons. The key construction is a map, given by Hausmann and Knutson, using the Hopf map on quaternions from the complex Stiefel manifold of 2‐frames in n‐space to the space of closed n‐gons in 3‐space of total length 2. Our probability measure on polygon space is defined by pushing forward Haar measure on the Stiefel manifold by this map. A similar construction yields a probability measure on plane polygons that comes from a real Stiefel manifold.The edgelengths of polygons sampled according to our measures obey beta distributions. This makes our polygon measures different from those usually studied, which have Gaussian or fixed edgelengths. One advantage of our measures is that we can explicitly compute expectations and moments for chord lengths and radii of gyration. Another is that direct sampling according to our measures is fast (linear in the number of edges) and easy to code.Some of our methods will be of independent interest in studying other probability measures on polygon spaces. We define an edge set ensemble (ESE) to be the set of polygons created by rearranging a given set of n edges. A key theorem gives a formula for the average over an ESE of the squared lengths of chords skipping k vertices in terms of k, n, and the edgelengths of the ensemble. This allows one to easily compute expected values of squared chord lengths and radii of gyration for any probability measure on polygon space invariant under rearrangements of edges. © 2014 Wiley Periodicals, Inc.
An end‐to‐end channel allocation scheme for a wireless mesh network
Authors: Tsao Shiao‐Li , Su Jiun‐Jang , Huang Kuei‐Li , Shih Yung‐Chien , Tseng Chien‐Chao 
Published: August 2013

SUMMARYCo‐channel interference seriously influences the throughput of a wireless mesh network. This study proposes an end‐to‐end channel allocation scheme (EECAS) that extends the radio‐frequency‐slot method to minimize co‐channel interference. The EECAS first separates the transmission and reception of packets into two channels. This scheme can then classify the state of each radio‐frequency‐slot as transmitting, receiving, interfered, free, or parity. A node that initiates a communication session with a quality of service requirement can propagate a channel allocation request along the communication path to the destination. By checking the channel state, the EECAS can determine feasible radio‐frequency‐slot allocations for the end‐to‐end path. The simulation results in this study demonstrate that the proposed approach performs well in intra‐mesh and inter‐mesh communications, and it outperforms previous channel allocation schemes in end‐to‐end throughput. Copyright © 2013 John Wiley & Sons, Ltd.
Eating disorders in a large clinical sample of men and women with personality disorders
Authors: Reas Deborah L. , Rø Øyvind , Karterud Sigmund , Hummelen Benjamin , Pedersen Geir 
Published: August 2013

ABSTRACTObjectiveWe assessed and compared the prevalence of anorexia nervosa (AN), bulimia nervosa (BN), and eating disorder not otherwise specified (EDNOS) across six Axis II groups (borderline, obsessive‐compulsive, avoidant, dependent, paranoid, and personality disorder NOS) and patients with major depressive disorder (MDD) without personality disorders (PD).MethodThe sample included 3,266 consecutive and first admissions to 16 different treatment units in the Norwegian Network of Psychotherapeutic Day Hospitals between 1993 and 2009. All patients were interviewed with the SCID‐II for DSM‐III‐R (prior to 1996) or DSM‐IV (from 1996) and the MINI for Axis I disorders in accordance with the LEAD (longitudinal, expert, all‐data) standard.ResultsThe prevalence of any ED in the PD sample was approximately 17% for women and 3% for men. A lower rate of ED (5%) was found for patients with MDD without PD. A significantly higher proportion of patients with borderline personality disorder were diagnosed with BN or EDNOS. The rate of AN was significantly elevated in female patients with obsessive‐compulsive personality disorder. Men demonstrated significantly less diagnostic co‐occurrence and no significant differential variation across PD groups or MDD.DiscussionData which included a psychiatric comparison group showed less co‐occurrence and non‐significant variation across PD groups for men, but demonstrated a meaningful and specific pattern of comorbidity between ED and PD for women. There was an elevated risk of ED among female patients with PD, most pronounced for borderline. An almost five‐fold higher rate of AN was found among women with obsessive‐compulsive PD. © 2013 Wiley Periodicals, Inc.(Int J Eat Disord 2013; 46:801–809)
Predicting rarity and decline in animals, plants, and mushrooms based on species attributes and indicator groups
Authors: Musters C. J. M. , Kalkman Vincent , van Strien Arco 
Published: August 2013

AbstractIn decisions on nature conservation measures, we depend largely on knowledge of the relationship between threats and environmental factors for a very limited number of species groups, with relevant environmental factors often being deduced from the relationship between threat and species traits. But can relationships between traits and levels of threats be identified across species from completely different taxonomic groups; and how accurately do well‐known taxonomic groups indicate levels of threat in other species groups? To answer these questions, we first made a list of 152 species attributes of morphological and demographic traits and habitat requirements. Based on these attributes we then grew random forests of decision trees for 1183 species in the 18 different taxonomic groups for which we had Red Lists available in the Netherlands, using these to classify animals, plants, and mushrooms according to their rarity and decline. Finally, we grew random forests for four species groups often used as indicator groups to study how well the relationship between attribute and decline within these groups reflected that relationship within the larger taxonomic group to which these groups belong. Correct classification of rarity based on all attributes was as high as 88% in animals, 85% in plants, and 94% in mushrooms and correct classification of decline was 78% in animals, 69% in plants, and 70% in mushrooms. Vertebrates indicated decline in all animals well, as did birds for all vertebrates and vascular plants for all plants. However, butterflies poorly indicated decline in all insects. Random forests are a useful tool to relate rarity and decline to species attributes thereby making it possible to generalize rarity and decline to a wider set of species groups. Random forests can be used to estimate the level of threat to complete faunas and floras of countries or regions. In regions like the Netherlands, conservation policy based on attributes known to be relevant for the decline to birds, vertebrates or plants will probably also impact all aboveground terrestrial and freshwater macrofauna or macrophytes.
Phenotypic plasticity of coralline algae in a High CO2 world
Authors: Ragazzola Federica , Foster Laura C. , Form Armin U. , Büscher Janina , Hansteen Thor H. , Fietzke Jan 
Published: August 2013

AbstractIt is important to understand how marine calcifying organisms may acclimatize to ocean acidification to assess their survival over the coming century. We cultured the cold water coralline algae, Lithothamnion glaciale, under elevated pCO2 (408, 566, 770, and 1024 μatm) for 10 months. The results show that the cell (inter and intra) wall thickness is maintained, but there is a reduction in growth rate (linear extension) at all elevated pCO2. Furthermore a decrease in Mg content at the two highest CO2 treatments was observed. Comparison between our data and that at 3 months from the same long‐term experiment shows that the acclimation differs over time since at 3 months, the samples cultured under high pCO2 showed a reduction in the cell (inter and intra) wall thickness but a maintained growth rate. This suggests a reallocation of the energy budget between 3 and 10 months and highlights the high degree plasticity that is present. This might provide a selective advantage in future high CO2 world.
Dioecy, more than monoecy, affects plant spatial genetic structure: the case study of Ficus
Authors: Nazareno Alison G. , Alzate‐Marin Ana L. , Pereira Rodrigo Augusto S. 
Published: August 2013

AbstractIn this analysis, we attempt to understand how monoecy and dioecy drive spatial genetic structure (SGS) in plant populations. For this purpose, plants of the genus Ficus were used as a comparative model due to their particular characteristics, including high species diversity, variation in life histories, and sexual systems. One of the main issues we assessed is whether dioecious fig tree populations are more spatially genetically structured than monoecious populations. Using the Sp statistic, which allows for quantitative comparisons among different studies, we compared the extent of SGS between monoecious and dioecious Ficus species. To broaden our conclusions we used published data on an additional 27 monoecious and dioecious plant species. Furthermore, genetic diversity analyses were performed for two monoecious Ficus species using 12 microsatellite markers in order to strengthen our conclusions about SGS. Our results show that dioecy, more than monoecy, significantly contributes to SGS in plant populations. On average, the estimate of Sp was six times higher for dioecious Ficus species than monoecious Ficus species and it was two times higher in dioecious than monoecious plant species. Considering these results, we emphasize that the long‐distance pollen dispersal mechanism in monoecious Ficus species seems to be the dominant factor in determining weak spatial genetic structure, high levels of genetic diversity, and lack of inbreeding. Although Ficus constitute a model species to study SGS, a more general comparison encompassing a wider range of plants is required in order to better understand how sexual systems affect genetic structure.
Glycerol – A Non‐Innocent Solvent for Rh‐Catalysed Pauson–Khand Carbocyclisations
Authors: Chahdoura Faouzi , Dubrulle Laurent , Fourmy Kevin , Durand Jérôme , Madec David , Gómez Montserrat 
Published: August 2013

AbstractRh‐catalysed carbocyclisations of the 1,6‐enynes 1–8 efficiently gave bicyclo[3.3.0]octenones in neat glycerol. Unexpectedly, ligand‐free [Rh(μ‐OMe)(cod)]2 was highly selective. Moreover, TPPTS [tris(3‐sulfonatophenyl)phosphane trisodium salt] improved the catalyst performance at low Rh/L ratios, but surprisingly, ligand excess blocked the reaction. Detailed NMR studies evidenced the role of glycerol in the catalytic process.
A Mach‐uniform preconditioner for incompressible and subsonic flows
Authors: Bas Onur , Tuncer Ismail H. , Kaynak Unver 
Published: August 2013

SUMMARYIn this study, a novel Mach‐uniform preconditioning method is developed for the solution of Euler equations at low subsonic and incompressible flow conditions. In contrast to the methods developed earlier in which the conservation of mass equation is preconditioned, in the present method, the conservation of energy equation is preconditioned, which enforces the divergence free constraint on the velocity field even at the limiting case of incompressible, zero Mach number flows. Despite most preconditioners, the proposed Mach‐uniform preconditioning method does not have a singularity point at zero Mach number. The preconditioned system of equations preserves the strong conservation form of Euler equations for compressible flows and recovers the artificial compressibility equations in the case of zero Mach number. A two‐dimensional Euler solver is developed for validation and performance evaluation of the present formulation for a wide range of Mach number flows. The validation cases studied show the convergence acceleration, stability, and accuracy of the present Mach‐uniform preconditioner in comparison to the non‐preconditioned compressible flow solutions. The convergence acceleration obtained with the present formulation is similar to those of the well‐known preconditioned system of equations for low subsonic flows and to those of the artificial compressibility method for incompressible flows. Copyright © 2013 John Wiley & Sons, Ltd.
Subjective stressors moderate effectiveness of a multi‐component, multi‐site intervention on caregiver depression and burden
Authors: Hatch Daniel J. , DeHart William B. , Norton Maria C. 
Published: August 2013

ObjectivesThe present study assessed whether caregiving contextual factors moderated outcomes of a caregiver intervention.MethodsExtant data from the Resources for Enhancing Alzheimer's Caregiver Health (REACH) II study, a randomized‐control trial of a multi‐component, multi‐site intervention for dementia caregivers was utilized. 498 caregivers {83.1% women; mean [standard deviation (SD)] age = 60.3 (13.1)}, and their care recipients [58.6% women, mean (SD) age = 78.5 (9.6)] were randomly assigned to intervention or control group. Multiple regression was used to regress Center for Epidemiological Studies of Depression Scale (CES‐D) and Zarit burden scores on the interaction between group membership and various factors reflecting the caregiving context.ResultsLower follow‐up CES‐D scores in the intervention group were found only for those: in the fourth quartile of baseline CES‐D (β = −0.13, p = 0.05; overall interaction p = 0.009), with high Revised Memory and Behavior Problems Checklist (RMBPC) stress (β = −0.16, p = 0.03) and with a home health aide (β = −0.29, p = 0.009). Diminished burden was found in the intervention group only for the following: those in the fourth quartile of baseline burden (β = −0.16, p = 0.01), and in the fourth quartile (β = −0.16, p = 0.05) of Mini Mental State Examination, and with high RMBPC stress (β = −0.18, p = 0.008), with a trend for diminished burden among those with a paid homemaker (β = −0.19, p = 0.075).ConclusionResults suggest greater intervention efficacy among caregivers experiencing subjective stress. Copyright © 2013 John Wiley & Sons, Ltd.
How hydrological factors initiate instability in a model sandy slope
Authors: Terajima Tomomi , Miyahira Ei‐ichiro , Miyajima Hiroyuki , Ochiai Hirotaka , Hattori Katsumi 
Published: August 2013

AbstractKnowledge of the mechanisms of rain‐induced shallow landslides can improve the prediction of their occurrence and mitigate subsequent sediment disasters. Here, we examine an artificial slope's subsurface hydrology and propose a new slope stability analysis that includes seepage force and the down‐slope transfer of excess shear forces. We measured pore water pressure and volumetric water content immediately prior to a shallow landslide on an artificial sandy slope of 32°: The direction of the subsurface flow shifted from downward to parallel to the slope in the deepest part of the landslide mass, and this shift coincided with the start of soil displacement. A slope stability analysis that was restricted to individual segments of the landslide mass could not explain the initiation of the landslide; however, inclusion of the transfer of excess shear forces from up‐slope to down‐slope segments improved drastically the predictability. The improved stability analysis revealed that an unstable zone expanded down‐slope with an increase in soil water content, showing that the down‐slope soil initially supported the unstable up‐slope soil; destabilization of this down‐slope soil was the eventual trigger of total slope collapse. Initially, the effect of apparent soil cohesion was the most important factor promoting slope stability, but seepage force became the most important factor promoting slope instability closer to the landslide occurrence. These findings indicate that seepage forces, controlled by changes in direction and magnitude of saturated and unsaturated subsurface flows, may be the main cause of shallow landslides in sandy slopes. Copyright © 2013 John Wiley & Sons, Ltd.