bluuebunny/crossref_metadata_2025 huggingface dataset:
Periphery‐Functionalized Porous Organic Cages
Authors: Reiss Paul S. , Little Marc A. , Santolini Valentina , Chong Samantha Y. , Hasell Tom , Jelfs Kim E. , Briggs Michael E. , Cooper Andrew I.
Published: October 2016

By synthesizing derivatives of a trans‐1,2‐diaminocyclohexane precursor, three new functionalized porous organic cages were prepared with different chemical functionalities on the cage periphery. The introduction of twelve methyl groups (CC16) resulted in frustration of the cage packing mode, which more than doubled the surface area compared to the parent cage, CC3. The analogous installation of twelve hydroxyl groups provided an imine cage (CC17) that combines permanent porosity with the potential for post‐synthetic modification of the cage exterior. Finally, the incorporation of bulky dihydroethanoanthracene groups was found to direct self‐assembly towards the formation of a larger [8+12] cage, rather than the expected [4+6], cage molecule (CC18). However, CC18 was found to be non‐porous, most likely due to cage collapse upon desolvation.
Doubly N‐Fused [24]Pentaphyrin Silicon Complex and Its Fluorosilicate: Enhanced Möbius Aromaticity in the Fluorosilicate
Authors: Ishida Shin‐ichiro , Kim Jun Oh , Kim Dongho , Osuka Atsuhiro
Published: October 2016

Treatment of nonaromatic N‐fused [24]pentaphyrin with trichloromethylsilane in the presence of a base afforded doubly N‐fused [24]pentaphyrin and its silicon complex. Addition of fluoride ion to the silicon complex led to the formation of its fluorosilicate as an unprecedented monoanionic six‐coordinated SiIV complex of porphyrinoid. Treatment of the fluorosilicate with acid led to the recovery of the silicon complex. The doubly N‐fused pentaphyrin, the silicon complex, and the fluorosilicate were all characterized as distinct Möbius aromatic molecules by spectroscopic measurements and X‐ray crystallographic analyses. Importantly, the second N‐fusion reaction, Si‐incorporation and fluoride addition to the Si‐atom enhanced the aromaticity of doubly N‐fused [24]pentaphyrins in this order. Tamao–Fleming oxidation of the silicon complex gave β‐keto doubly N‐fused pentaphyrin and triply fused [24]pentaphyrin, which were nonaromatic and Hückel anti‐aromatic, respectively.
A Multi‐responsive Regenerable Europium–Organic Framework Luminescent Sensor for Fe3+, CrVI Anions, and Picric Acid
Authors: Liu Wei , Huang Xin , Xu Cong , Chen Chunyang , Yang Lizi , Dou Wei , Chen Wanmin , Yang Huan , Liu Weisheng
Published: October 2016

A novel luminescent microporous lanthanide metal–organic framework (Ln‐MOF) based on a urea‐containing ligand has been successfully assembled. Structural analysis revealed that the framework features two types of 1D channels, with urea N−H bonds projecting into the pores. Luminescence studies have revealed that the Ln‐MOF exhibits high sensitivity, good selectivity, and a fast luminescence quenching response towards Fe3+, CrVI anions, and picric acid. In particular, in the detection of Cr2O72− and picric acid, the Ln‐MOF can be simply and quickly regenerated, thus exhibiting excellent recyclability. To the best of our knowledge, this is the first example of a multi‐responsive luminescent Ln‐MOF sensor for Fe3+, CrVI anions, and picric acid based on a urea derivative. This Ln‐MOF may potentially be used as a multi‐responsive regenerable luminescent sensor for the quantitative detection of toxic and harmful substances.
Hydroperoxyl Radicals (HOO.): Vitamin E Regeneration and H‐Bond Effects on the Hydrogen Atom Transfer
Authors: Cedrowski Jakub , Litwinienko Grzegorz , Baschieri Andrea , Amorati Riccardo
Published: October 2016

Hydroperoxyl (HOO.) and alkylperoxyl (ROO.) radicals show a different behavior in H‐atom‐transfer processes. Both radicals react with an analogue of α‐tocopherol (TOH), but HOO., unlike ROO., is able to regenerate TOH by a fast H‐atom transfer: TO.+HOO.→TOH+O2. The kinetic solvent effect on the H‐atom transfer from TOH to HOO. is much stronger than that observed for ROO. because noncovalent interactions with polar solvents (Solv⋅⋅⋅HOO.) destabilize the transition state.
The Me3NB12Cl11. Radical: A Strong One‐Electron Oxidizing Agent
Authors: Bertocco Philipp , Bolli Christoph , Derendorf Janis , Jenne Carsten , Klein Axel , Stirnat Kathrin
Published: October 2016

Strong oxidizing agents often contain fluorine and are not compatible with substrates forming strong element–fluorine bonds. Therefore, there is need for new strong oxidizers. Cyclic voltammetric measurements on the weakly coordinating anion [Me3NB12Cl11]− in liquid SO2 revealed an oxidation wave at +2.59 V versus Fc0/+. The oxidation of Na[Me3NB12Cl11] with AsF5 in liquid sulfur dioxide gives the boron‐cluster‐based radical Me3NB12Cl11. as a dark blue solid in quantitative yield. The radical was characterized by vibrational, NMR, and EPR spectroscopy and by its crystal structure. To explore the potential of the radical Me3NB12Cl11. to act as a strong oxidizing agent, it was reacted with different compounds having high ionization energies. Thianthrene (ionization energy 7.8 eV) and hexabromobenzene (8.8 eV) were oxidized to the corresponding cations. The reaction with elemental iodine (9.3 eV) gave the [I5]+ cation. These reactive cations are stabilized in the solid state by the weakly coordinating anion [Me3NB12Cl11]−, which was formed as a reduced product in the oxidation reactions.
Synthesis Strategies for Ultrastable Zeolite GIS Polymorphs as Sorbents for Selective Separations
Authors: Oleksiak Matthew D. , Ghorbanpour Arian , Conato Marlon T. , McGrail B. Peter , Grabow Lars C. , Motkuri Radha Kishan , Rimer Jeffrey D.
Published: October 2016

Invited for the cover of this issue are the groups of R. K. Motkuri and J. D. Rimer at the Pacific Northwest National Laboratory and University of Houston, respectively. The image depicts bulk sorbents that can be used for separations, a microscopic image of a zeolite crystal framework, and an individual pore operating as a size‐exclusion sieve. Read the full text of the article at 10.1002/chem.201602653.
Hierarchical Analysis of Self‐Assembled PEGylated Hexaphenylalanine Photoluminescent Nanostructures
Authors: Diaferia Carlo , Sibillano Teresa , Balasco Nicole , Giannini Cinzia , Roviello Valentina , Vitagliano Luigi , Morelli Giancarlo , Accardo Antonella
Published: October 2016

Despite the growing literature about diphenylalanine‐based peptide materials, it still remains a challenge to delineate the theoretical insight into peptide nanostructure formation and the structural features that could permit materials with enhanced properties to be engineered. Herein, we report the synthesis of a novel peptide building block composed of six phenylalanine residues and eight PEG units, PEG8‐F6. This aromatic peptide self‐assembles in water in stable and well‐ordered nanostructures with optoelectronic properties. A variety of techniques, such as fluorescence, FTIR, CD, DLS, SEM, SAXS, and WAXS allowed us to correlate the photoluminescence properties of the self‐assembled nanostructures with the structural organization of the peptide building block at the micro‐ and nanoscale. Finally, a model of hexaphenylalanine in aqueous solution by molecular dynamics simulations is presented to suggest structural and energetic factors controlling the formation of nanostructures.
Flory‐Huggins solution theory for heavy oils
Authors: Mohan Vijitha , Neogi Parthasakha , Bai Baojun
Published: October 2016

The addition of a solvent to heavy crude oil causes reduction in its viscosity and facilitates extraction. Existing data on swelling of oil in the presence of solvent in vapour form have been analyzed using the Flory‐Huggins theory. The model uses volume fractions and hence problems related to an appropriate average molecular weight of oil to use in the calculations are avoided. The data expressed in terms of swelling as a function of solvent partial pressure fit well with the model when the solvent vapour can condense and is miscible with oil or immiscible with oil or even when condensation is not possible. We are also able to predict when phase separation can occur (which we take to be asphaltene precipitation) in the solution although the above experiments have not looked at this aspect.
Heavy oil upgrading in a hydrodynamic cavitation system: CFD modelling, effect of the presence of hydrogen donor and metal nanoparticles
Authors: Askarian Mohammad , Vatani Ali , Edalat Mohsen
Published: October 2016

The cavitation technique with the use of a proper hydrogen donor can be used to upgrade heavy oils, such as atmospheric and vacuum residues and lower the difficulties of their transportation and exploitation. On the other hand, the very high localized temperature experienced in collapsing bubbles may activate the dispersed metal nanoparticles, and therefore the cracking or hydrogenation reactions may be catalyzed through the cavitation process of heavy oils.

This paper investigated numerically the formation of a vapour phase in the cavitation chamber of a home‐made laboratory hydrodynamic cavitation setup and also investigated the upgrading of a sample of heavy fuel oil in the presence of gasoline as a hydrogen donor and metal nanoparticles. The results indicated that adding 0.01 L/L gasoline to a 10‐min cavitational cracking process at 80 °C and atmospheric pressure can reduce the viscosity of heavy oil by about 20 %. In addition, the presence of iron nanoparticles can increase the rate of hydrogenation and/or cracking reactions in the heavy oil cavitational upgrading process (HCUP) in the presence of a hydrogen donor.
An implicit solver for 1D arterial network models
Authors: Carson Jason , Van Loon Raoul
Published: October 2016

In this study, the 1D blood flow equations are solved using a newly proposed enhanced trapezoidal rule method (ETM), which is an extension to the simplified trapezoidal rule method. At vessel junctions, the conservation of mass and conservation of total pressure are held as system constraints using Lagrange multipliers that can be physically interpreted as external flow rates. The ETM scheme is compared with published arterial network benchmark problems and a dam break problem. Strengths of the ETM scheme include being simple to implement, intuitive connection to lumped parameter models, and no restrictive stability criteria such as the Courant‐Friedrichs‐Lewy (CFL) number. The ETM scheme does not require the use of characteristics at vessel junctions, or for inlet and outlet boundary conditions. The ETM forms an implicit system of equations, which requires only one global solve per time step for pressure, followed by flow rate update on the elemental system of equations; thus, no iterations are required per time step. Consistent results are found for all benchmark cases, and for a 56‐vessel arterial network problem, it gives very satisfactory solutions at a spatial and time discretization that results in a maximum CFL of 3, taking 4.44 seconds per cardiac cycle. By increasing the time step and element size to produce a maximum CFL number of 15, the method takes only 0.39 second per cardiac cycle with only a small compromise on accuracy.
The Mind Bending Quest for Cognitive Enhancers
Authors: Arce E , Ehlers MD
Published: October 2016

Adequate cognitive functioning is essential for daily activities. When there is an insult to the brain, cognitive abilities can suffer, which, in turn, produce substantial medical and functional impairment. Advances in neurobiology, circuit neuroscience, and clinical assessment technology are converging in a manner that holds promise for the development of new pharmacological agents for cognitive enhancement in neuropsychiatric disease.
Quantitative Systems Pharmacology: A Case for Disease Models
Authors: Musante CJ , Ramanujan S , Schmidt BJ , Ghobrial OG , Lu J , Heatherington AC
Published: October 2016

Quantitative systems pharmacology (QSP) has emerged as an innovative approach in model‐informed drug discovery and development, supporting program decisions from exploratory research through late‐stage clinical trials. In this commentary, we discuss the unique value of disease‐scale “platform” QSP models that are amenable to reuse and repurposing to support diverse clinical decisions in ways distinct from other pharmacometrics strategies.
An Interview With the Association for Spiritual, Ethical, and Religious Values in Counseling Leaders: Craig S. Cashwell and J. Scott Young
Authors: Flasch Paulina
Published: October 2016

American Counseling Association Fellows, past presidents of the Association for Spiritual, Ethical, and Religious Values in Counseling (ASERVIC), and close friends, Drs. Craig S. Cashwell and J. Scott Young have made a significant impact on the field of spirituality counseling over the past 20 years. This interview emphasizes their involvement in ASERVIC and the spirituality counseling field over the course of their careers and in the present, as well as the wisdom they have gained from their experiences.
African American Counselors‐in‐Training, the Black Church, and Lesbian‐, Gay‐, and Bisexual‐Affirmative Counseling: Considerations for Counselor Education Programs
Authors: Robertson Derek L. , Avent Janeé R.
Published: October 2016

This article examines the challenges that may be particular to African American counseling students who identify as Christian in learning to provide competent and affirming counseling to lesbian, gay, and bisexual (LGB) clients. The role and importance of the Black Church, race survival consciousness, and cultural constructions of sexuality and mental health may present unique barriers for these students in affirming LGB clients. Recommendations for counselor education programs are discussed.
Acceptance and Commitment Therapy as a Spiritually Integrated Psychotherapy
Authors: Santiago Pia Newell , Gall Terry Lynn
Published: October 2016

This article presents acceptance and commitment therapy (ACT) as a spiritually integrated therapeutic modality. ACT is a value‐driven therapy that involves facilitating transcendence of physical, mental, and emotional experience to alleviate human suffering; as such, ACT shares common ground with the domain of spirituality. Approached as a spiritually integrated therapy, ACT can help clients to access spiritual resources and create life meaning as well as aid in the resolution or transformation of spiritual struggles. Given that spiritual struggles, in particular, can have a significant impact on mental health and well‐being, this article provides guidance in how ACT can address such struggles.
The corticospinal tract: Evolution, development, and human disorders
Authors: Welniarz Quentin , Dusart Isabelle , Roze Emmanuel
Published: October 2016

The corticospinal tract (CST) plays a major role in cortical control of spinal cord activity. In particular, it is the principal motor pathway for voluntary movements. Here, we discuss: (i) the anatomic evolution and development of the CST across mammalian species, focusing on its role in motor functions; (ii) the molecular mechanisms regulating corticospinal tract formation and guidance during mouse development; and (iii) human disorders associated with abnormal CST development. A comparison of CST anatomy and development across mammalian species first highlights important similarities. In particular, most CST axons cross the anatomical midline at the junction between the brainstem and spinal cord, forming the pyramidal decussation. Reorganization of the pattern of CST projections to the spinal cord during evolution led to improved motor skills. Studies of the molecular mechanisms involved in CST formation and guidance in mice have identified several factors that act synergistically to ensure proper formation of the CST at each step of development. Human CST developmental disorders can result in a reduction of the CST, or in guidance defects associated with abnormal CST anatomy. These latter disorders result in altered midline crossing at the pyramidal decussation or in the spinal cord, but spare the rest of the CST. Careful appraisal of clinical manifestations associated with CST malformations highlights the critical role of the CST in the lateralization of motor control. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 810–829, 2017
Anatomical and functional neuroimaging in awake, behaving marmosets
Authors: Silva Afonso C.
Published: October 2016

The common marmoset (Callithrix jacchus) is a small New World monkey that has gained significant recent interest in neuroscience research, not only because of its compatibility with gene editing techniques, but also due to its tremendous versatility as an experimental animal model. Neuroimaging modalities, including anatomical (MRI) and functional magnetic resonance imaging (fMRI), complemented by two‐photon laser scanning microscopy and electrophysiology, have been at the forefront of unraveling the anatomical and functional organization of the marmoset brain. High‐resolution anatomical MRI of the marmoset brain can be obtained with remarkable cytoarchitectonic detail. Functional MRI of the marmoset brain has been used to study various sensory systems, including somatosensory, auditory, and visual pathways, while resting‐state fMRI studies have unraveled functional brain networks that bear great correspondence to those previously described in humans. Two‐photon laser scanning microscopy of the marmoset brain has enabled the simultaneous recording of neuronal activity from thousands of neurons with single cell spatial resolution. In this article, we aim to review the main results obtained by our group and by our colleagues in applying neuroimaging techniques to study the marmoset brain. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 373–389, 2017
Application of viral vectors to the study of neural connectivities and neural circuits in the marmoset brain
Authors: Watakabe Akiya , Sadakane Osamu , Hata Katsusuke , Ohtsuka Masanari , Takaji Masafumi , Yamamori Tetsuo
Published: October 2016

It is important to study the neural connectivities and functions in primates. For this purpose, it is critical to be able to transfer genes to certain neurons in the primate brain so that we can image the neuronal signals and analyze the function of the transferred gene. Toward this end, our team has been developing gene transfer systems using viral vectors. In this review, we summarize our current achievements as follows. 1) We compared the features of gene transfer using five different AAV serotypes in combination with three different promoters, namely, CMV, mouse CaMKII (CaMKII), and human synapsin 1 (hSyn1), in the marmoset cortex with those in the mouse and macaque cortices. 2) We used target‐specific double‐infection techniques in combination with TET‐ON and TET‐OFF using lentiviral retrograde vectors for enhanced visualization of neural connections. 3) We used an AAV‐mediated gene transfer method to study the transcriptional control for amplifying fluorescent signals using the TET/TRE system in the primate neocortex. We also established systems for shRNA mediated gene targeting in a neocortical region where a gene is significantly expressed and for expressing the gene using the CMV promoter for an unexpressed neocortical area in the primate cortex using AAV vectors to understand the regulation of downstream genes. Our findings have demonstrated the feasibility of using viral vector mediated gene transfer systems for the study of primate cortical circuits using the marmoset as an animal model. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 354–372, 2017
Species distribution models may misdirect assisted migration: insights from the introduction of Douglas‐fir to Europe
Authors: Boiffin Juliette , Badeau Vincent , Bréda Nathalie
Published: October 2016

Species distribution models (SDMs), which statistically relate species occurrence to climatic variables, are widely used to identify areas suitable for species growth under future climates and to plan for assisted migration. When SDMs are projected across times or spaces, it is assumed that species climatic requirements remain constant. However, empirical evidence supporting this assumption is rare, and SDM predictions could be biased. Historical human‐aided movements of tree species can shed light on the reliability of SDM predictions in planning for assisted migration. We used Douglas‐fir (Pseudotsuga menziesii(Mirb.) Franco), a North American conifer introduced into Europe during the mid‐19th century, as a case‐study to test niche conservatism. We combined transcontinental data sets of Douglas‐fir occurrence and climatic predictors to compare the realized niches between native and introduced ranges. We calibrated a SDM in the native range and compared areas predicted to be climatically suitable with observed presences. The realized niches in the native and introduced ranges showed very limited overlap. The SDM calibrated in North America had very high predictive power in the native range, but failed to predict climatic suitability in Europe where Douglas‐fir grows in climates that have no analogue in the native range. We review the ecological mechanisms and silvicultural practices that can trigger such shifts in realized niches. Retrospective analysis of tree species introduction revealed that the assumption of niche conservatism is erroneous. As a result, distributions predicted by SDM are importantly biased. There is a high risk that assisted migration programs may be misdirected and target inadequate species or introduction zones.
Detecting state changes for ecosystem conservation with long‐term monitoring of species composition
Authors: Mason T. J. , Keith D. A. , Letten A. D.
Published: October 2016

Effective conservation requires an understanding not only of contemporary vegetation distributions in the landscape, but also cognizance of vegetation transitions over time with the goal of maintaining persistence of all states within the landscape. Using a state and transition model framework, we investigated temporal transitions over 31 years in species composition among five upland swamp vegetation communities in southeastern Australia. We applied fuzzy clustering to document transitions across communities; evaluated the resilience and resistance of communities to change; and explored the relationship between ecosystem states and major environmental factors posited to structure the system. We also evaluated the predictive ability of an established vegetation dynamics model. We found that community composition remained stable or underwent reversible or directional transitions depending on the vegetation type. Wetter communities (Ti‐tree thicket and Cyperoid heath) were more stable (i.e., resistant) while drier communities showed a greater propensity to transition (i.e., had lower resistance) under the observed disturbance regime (low variance fire intervals). The resilience of drier communities differed under this regime, with Banksia thicket showing reversible compositional change, while Restioid heath and Sedgeland showed directional change. In accord with an established conceptual model, we found that communities were distributed along a hydrological gradient. In addition, vegetation structure, along with light penetration to ground level, differentiated communities. However, internal dynamics of drier communities were complex: differences in fire regime (penultimate fire interval in 2014 and number of fires since 1965) were unable to predict differences in community membership among sites. Aspects of the fire regime are expected to be more important predictors if fire intervals vary more strongly among sites in the future. Fuzzy clustering of compositional data allows managers to track community transitions over time and facilitates planned interventions for conservation purposes.
Predicting North American Scolytinae invasions in the Southern Hemisphere
Authors: Lantschner Maria Victoria , Atkinson Thomas H. , Corley Juan C. , Liebhold Andrew M.
Published: October 2016

Scolytinae species are recognized as one of the most important tree mortality agents in coniferous forests worldwide, and many are known invaders because they are easily transported in wood products. Nonnative trees planted in novel habitats often exhibit exceptional growth, in part because they escape herbivore (such as Scolytinae) pressure from their native range. Increasing accidental introductions of forest pest species as a consequence of international trade, however, is expected to diminish enemy release of nonnative forest trees. In this context, there is need to characterize patterns of forest herbivore species invasion risks at global scales. In this study, we analyze the establishment potential of 64 North American Scolytinae species in the Southern Hemisphere. We use climate‐based ecological niche models (MaxEnt) to spatially define the potential distribution of these Scolytinae species in regions of the Southern Hemisphere were pines are planted. Our model predicts that all of the pine‐growing regions of the Southern Hemisphere are capable of supporting some species of North American Scolytinae, but there are certain “hotspot” regions, southeastern Argentina, Bolivia, Chile, Peru and southwestern Australia, that appear to be suitable for a particularly large number of species. The species with the highest predicted risk of establishment were Dendroctonus valens, Xyleborus intrusus, Hylastes tenuis, Ips grandicollis, Gnathotrichus sulcatus, and Ips calligraphus. Given that global commerce is anticipated to continue to increase, we can expect that more Scolytinae species will continue to establish outside their range. Our results provide information useful for identifying a global list of potential invasive species in pine plantations, and may assist in the design of comprehensive strategies aimed at reducing pest establishment in Southern Hemisphere forest plantations.
Effects of sulfate and sulfide on the life cycle ofZizania palustrisin hydroponic and mesocosm experiments
Authors: Pastor John , Dewey Brad , Johnson Nathan W. , Swain Edward B. , Monson Philip , Peters Emily B. , Myrbo Amy
Published: October 2016

Under oxygenated conditions, sulfate is relatively non‐toxic to aquatic plants. However, in water‐saturated soils, which are usually anoxic, sulfate can be reduced to toxic sulfide. Although the direct effects of sulfate and sulfide on the physiology of a few plant species have been studied in some detail, their cumulative effects on a plant's life cycle through inhibition of seed germination, seedling survival, growth, and seed production have been less well studied. We investigated the effect of sulfate and sulfide on the life cycle of wild rice (Zizania palustrisL.) in hydroponic solutions and in outdoor mesocosms with sediment from a wild rice lake. In hydroponic solutions, sulfate had no effect on seed germination or juvenile seedling growth and development, but sulfide greatly reduced juvenile seedling growth and development at concentrations greater than 320 μg/L. In outdoor mesocosms, sulfate additions to overlying water increased sulfide production in sediments. Wild rice seedling emergence, seedling survival, biomass growth, viable seed production, and seed mass all declined with sulfate additions and hence sulfide concentrations in sediment. These declines grew steeper during the course of the 5 yr of the mesocosm experiment and wild rice populations became extinct in most tanks with concentrations of 250 mg SO4/L or greater in the overlying water. Iron sulfide precipitated on the roots of wild rice plants, especially at high sulfate application rates. These precipitates, or the encroachment of reducing conditions that they indicate, may impede nutrient uptake and be partly responsible for the reduced seed production and viability.
Testing the reproductive and somatic trade‐off in female Columbian ground squirrels
Authors: Rubach Kristin , Wu Mingyan , Abebe Asheber , Dobson F. Stephen , Murie Jan O. , Viblanc Vincent A.
Published: October 2016

Energetic trade‐offs in resource allocation form the basis of life‐history theory, which predicts that reproductive allocation in a given season should negatively affect future reproduction or individual survival. We examined how allocation of resources differed between successful and unsuccessful breeding female Columbian ground squirrels to discern any effects of resource allocation on reproductive and somatic efforts. We compared the survival rates, subsequent reprodction, and mass gain of successful breeders (females that successfully weaned young) and unsuccessful breeders (females that failed to give birth or wean young) and investigated “carryover” effects to the next year. Starting capital was an important factor influencing whether successful reproduction was initiated or not, as females with the lowest spring emergence masses did not give birth to a litter in that year. Females that were successful and unsuccessful at breeding in one year, however, were equally likely to be successful breeders in the next year and at very similar litter sizes. Although successful and unsuccessful breeding females showed no difference in over winter survival, females that failed to wean a litter gained additional mass during the season when they failed. The next year, those females had increased energy “capital” in the spring, leading to larger litter sizes. Columbian ground squirrels appear to act as income breeders that also rely on stored capital to increase their propensity for future reproduction. Failed breeders in one year “prepare” for future reproduction by accumulating additional mass, which is “carried over” to the subsequent reproductive season.
The interplay between soil structure, roots, and microbiota as a determinant of plant–soil feedback
Authors: Bergmann Joana , Verbruggen Erik , Heinze Johannes , Xiang Dan , Chen Baodong , Joshi Jasmin , Rillig Matthias C.
Published: October 2016

Plant–soil feedback (PSF) can influence plant community structure via changes in the soil microbiome. However, how these feedbacks depend on the soil environment remains poorly understood. We hypothesized that disintegrating a naturally aggregated soil may influence the outcome of PSF by affecting microbial communities. Furthermore, we expected plants to differentially interact with soil structure and the microbial communities due to varying root morphology. We carried out a feedback experiment with nine plant species (five forbs and four grasses) where the “training phase” consisted of aggregated versus disintegrated soil. In the feedback phase, a uniform soil was inoculated in a fully factorial design with soil washings from conspecific‐ versus heterospecific‐trained soil that had been either disintegrated or aggregated. This way, the effects of prior soil structure on plant performance in terms of biomass production and allocation were examined. In the training phase, soil structure did not affect plant biomass. But on disintegrated soil, plants with lower specific root length (SRL) allocated more biomass aboveground. PSF in the feedback phase was negative overall. With training on disintegrated soil, conspecific feedback was positively correlated with SRL and significantly differed between grasses and forbs. Plants with higher SRL were likely able to easily explore the disintegrated soil with smaller pores, while plants with lower SRL invested in belowground biomass for soil exploration and seemed to be more susceptible to fungal pathogens. This suggests that plants with low SRL could be more limited by PSF on disintegrated soils of early successional stages. This study is the first to examine the influence of soil structure on PSF. Our results suggest that soil structure determines the outcome of PSF mediated by SRL. We recommend to further explore the effects of soil structure and propose to include root performance when working with PSF.
Do foraging methods in winter affect morphology during growth in juvenile snow geese?
Authors: Jónsson Jón Einar , Afton Alan D.
Published: October 2016

Physical exertion during growth can affect ultimate size and density of skeletal structures. Such changes from different exercise regimes may explain morphological differences between groups, such as those exhibited by lesser snow geese (Chen caerulescens caerulescens; hereafter snow geese) foraging in southwest Louisiana. In rice‐prairie habitats (hereafter rice‐prairies), snow geese bite off or graze aboveground vegetation, whereas they dig or grub for subterranean plant parts in adjacent coastal marshes. Grubbing involves considerably more muscular exertion than does grazing. Thus, we hypothesized that rates of bone formation and growth would be lower for juveniles wintering in rice‐prairies than those in coastal marshes, resulting in smaller bill and skull features at adulthood. First, we tested this exertion hypothesis by measuring bills, skulls, and associated musculature from arrival to departure (November–February) in both habitats in southwest Louisiana, using both banded birds and collected specimens. Second, we used the morphological data to test an alternative hypothesis, which states that smaller bill dimensions in rice‐prairies evolved because of hybridization with Ross's geese (C. rossii). Under the exertion hypothesis, we predicted that bill and skull bones of juveniles would grow at different rates between habitats. However, we found that bill and skull bones of juveniles grew similarly between habitats, thus failing to support the exertion hypothesis. Morphometrics were more likely to differ by sex or change with sampling date than to differ by habitat. We predicted that significant, consistent skewness toward smaller birds could indicate hybridization with Ross's geese, but no skewness was observed in our morphological data, which fails to support the hybridization hypothesis. Further research is needed to clarify whether snow geese wintering in Louisiana represent a single polymorphic population that segregates into individually preferred habitats, which we believe at present to be more likely as an explanation than two ecologically and spatially distinct morphotypes.
Higher efficiency of ISSR markers over plastid psbA‐trnH region in resolving taxonomical status of genus Ocimum L.
Authors: Kumar Amit , Mishra Priyanka , Baskaran Kuppusamy , Shukla Ashutosh K. , Shasany Ajit K. , Sundaresan Velusamy
Published: October 2016

High level of morphological as well as chemical variability exists within the genus Ocimum, and its taxonomy and phylogenetic relationships are still doubtful. For evaluating interspecific genetic relationships among the Ocimum species, genotyping with intersimple sequence repeat (ISSR) markers and sequence analyses of noncoding psbA‐trnH intergenic region belonging to chloroplast DNA were carried out. Although ISSR markers are highly efficient and reproducible, they have not been used extensively in phylogenetic studies. The use of the plastidial barcode candidate was expected to provide more variable and informative insight into evolutionary rates, and was thus employed as a phylogenetic marker to assess interspecific relationships. This study revealed that the ISSR markers were more efficient than psbA‐trnH sequences in resolving the current status of Ocimum L. genus. Distance‐ and character‐based methodological approaches applied on the molecular data with biparental and maternal inheritance were used for deducing the phylogenetic relationships among Ocimum species. Average polymorphic information content (0.344) and resolving power (6.285) depicted through ISSR markers proved to be efficient in discriminating the studied species of Ocimum. The primers used in this study revealed 99.585% polymorphism across the species demonstrating the polymorphic nature of ISSR markers.
Citations increase with manuscript length, author number, and references cited in ecology journals
Authors: Fox Charles W. , Paine C. E. Timothy , Sauterey Boris
Published: October 2016

Most top impact factor ecology journals indicate a preference or requirement for short manuscripts; some state clearly defined word limits, whereas others indicate a preference for more concise papers. Yet evidence from a variety of academic fields indicates that within journals longer papers are both more positively reviewed by referees and more highly cited. We examine the relationship between citations received and manuscript length, number of authors, and number of references cited for papers published in 32 ecology journals between 2009 and 2012. We find that longer papers, those with more authors, and those that cite more references are cited more. Although paper length, author count, and references cited all positively covary, an increase in each independently predicts an increase in citations received, with estimated relationships positive for all the journals we examined. That all three variables covary positively with citations suggests that papers presenting more and a greater diversity of data and ideas are more impactful. We suggest that the imposition of arbitrary manuscript length limits discourages the publication of more impactful studies. We propose that journals abolish arbitrary word or page limits, avoid declining papers (or requiring shortening) on the basis of length alone (irrespective of content), and adopt the philosophy that papers should be as long as they need to be.
Using hydrogen isotopes of freshwater fish tissue as a tracer of provenance
Authors: Soto David X. , Hobson Keith A. , Wassenaar Leonard I.
Published: October 2016

Hydrogen isotope (δ2H) measurements of consumer tissues in aquatic food webs are useful tracers of diet and provenance and may be combined with δ13C and δ15N analyses to evaluate complex trophic relationships in aquatic systems. However, δ2H measurements of organic tissues are complicated by analytical issues (e.g., H exchangeability, lack of matrix‐equivalent calibration standards, and lipid effects) and physiological mechanisms, such as H isotopic exchange with ambient water during protein synthesis and the influence of metabolic water. In this study, δ2H (and δ15N) values were obtained from fish muscle samples from Lake Winnipeg, Canada, 2007–2010, and were assessed for the effects of species, feeding habits, and ambient water δ2H values. After lipid removal, we used comparative equilibration to calibrate muscle δ2H values to nonexchangeable δ2H equivalents and controlled for H isotopic exchange between sample and laboratory ambient water vapor. We then examined the data for evidence of trophic δ2H enrichment by comparing δ2H values with δ15N values. Our results showed a significant logarithmic correlation between fork length and δ2H values, and no strong relationships between δ15N and δ2H. This suggests the so‐called apparent trophic compounding effect and the influence of metabolic water into tissue H were the potential mechanisms for δ2H enrichment. We evaluated the importance of water in controlling δ2H values of fish tissues and, consequently, the potential of H isotopes as a tracer of provenance by taking account of confounding variables such as body size and trophic effects. The δ2H values of fish appear to be a good tracer for tracking provenance, and we present a protocol for the use of H isotopes in aquatic ecosystems, which should be applicable to a broad range of marine and freshwater fish species. We advise assessing size effects or working with fish of relatively similar mass when inferring fish movements using δ2H measurements.
Responses of riparian plants to habitat changes following restoration of channelized streams
Authors: Kuglerová Lenka , Botková Kamila , Jansson Roland
Published: October 2016

The ecological effects of stream restoration were evaluated by comparing riparian vegetation, flooding, and habitat properties between channelized and two types of restored streams in northern Sweden. Channelized streams were straightened and cleared of in‐stream boulders and wood >50 years ago to facilitate timber floating. Basic restoration (performed 8–10 years ago) returned cleared material back to the channels, and enhanced restoration (3 years ago) added large structural elements (boulders and downed trees) to previously basic‐restored streams. Riparian inundation duration increased only after enhanced restoration. Similarly, enhanced‐restored reaches had the highest amount of substrate available for plant establishment compared to channelized and basic‐restored streams. In contrast, soil biochemical properties (pH and C:N ratio) did not improve following either restoration effort. Riparian plant cover was higher at both restored types than channelized reaches. Plant species richness was higher at plot‐scale level (0.25 m2) at both restored types in the most species‐rich elevation levels compared to channelized reaches, whereas at the reach‐scale (>700 m2 of riparian area), species richness did not differ among stream types. Similarly, species composition segregated between channelized and restored reaches only at the plot scale. We found no significant differences in riparian vegetation between the two restored types. The lack of positive responses of vegetation to enhanced restoration and to variables that changed immediately after restoration (inundation, habitat area) implies that responses were either slower than expected or the changes in hydrology and substrate availability were not as important for riparian flora as believed.
From facilitative to competitive interactions between woody plants and plants with crassulacean acid metabolism (CAM): The role of hydraulic descent
Authors: Yu Kailiang , D'Odorico Paolo
Published: October 2016

Woody plants may facilitate the establishment of seedlings with crassulacean acid metabolism (CAM) by ameliorating the abiotic environment through an increase in soil water availability. Because of the low transpiration rate in shallow‐rooted CAM plants and the consequently high soil water contents in the shallow soil, deep‐rooted trees in tree–CAM associations could perform hydraulic descent transporting water from wetter shallow soil to drier deep soil in arid environments. It remains unclear, however, whether a high rate of hydraulic descent can turn the facilitation of CAM plants by woody plants into competition. In this study, we develop a mechanistic model to investigate the facilitation of shallow‐rooted CAM plants by deep‐rooted woody plants in the access to soil water resources along a rainfall gradient. The model results show that in the case of low‐to‐moderate root overlap woody plants could facilitate CAM plants in access to soil water; this effect is mainly induced by the reduction in evaporation from the soil surface due to shading. Both shading and hydraulic descent decrease (or hydraulic lift increases) along a rainfall gradient, thereby favoring facilitation. Investment in deep roots by woody plants is usually thought to increase niche differentiation with shallow‐rooted plants, thereby reducing the competition and promoting species coexistence. This study indicates that deep root development could also favor competition through the mechanism of hydraulic descent, thereby changing our understanding of the role of root depth in niche differentiation between shallow and deep‐rooted plants.
Some like it hot: effect of environment on population dynamics of a small tropical seabird in the Caribbean region
Authors: Precheur Carine , Barbraud Christophe , Martail Fred , Mian Maurice , Nicolas Jean‐Claude , Brithmer Ronald , Belfan David , Conde Béatrice , Bretagnolle Vincent
Published: October 2016

An understanding of how environmental changes affect life history traits and population dynamics is essential for predicting the effects of climate change, managing ecosystems, and determining how species and habitats can best be preserved. This applies particularly to seabirds, which, as top marine predators, are often considered as indicators of marine ecosystem changes. Most studies have so far been conducted in polar or temperate regions. However, important changes in the functioning of tropical marine ecosystems have been reported, but the responses of top predators remain poorly known. This study focused on a tropical seabird, Audubon's shearwaterPuffinus lherminieri, analyzing the relationships between climate change and the survival of adults, nesting success, and population dynamics. The population studied breeds in Martinique, in the south of the Caribbean region, which is strongly influenced by the Amazon and Orinoco rivers. A data set for the period 1995 to 2014 was used to estimate the survival by age classes and breeding success and to determine which climate variables most affected demographic parameters. The population dynamics were modeled to predict the future population growth rates in response to climate change. The annual adult survival rate increased over the last 20 years, currently standing at 94% for adult birds more than 6 years old. Adult survival increased with sea surface temperature (SST) during the nonbreeding season as well as with Amazon River discharge, although the latter with a lag of 1 year. The effect ofSSTwas explained by the positive relationship betweenSSTand chlorophylladuring years of high discharge from the Amazon and Orinoco. The population decreased between 1995 and 2007 at a rate of 3% per year and then increased between 2008 and 2014 at a rate of 7% per year. The increase in adult survival observed should continue as temperatures increase in the future, and the population models predicted a stable or increasing population over the next 50 years (λ = 1.018). These results contrast with the negative effect of increasingSSTon seabird populations found in temperate and polar regions, emphasizing the need to study the impact of climate change on tropical seabirds.
Noninvasive unmanned aerial vehicle provides estimates of the energetic cost of reproduction in humpback whales
Authors: Christiansen Fredrik , Dujon Antoine M. , Sprogis Kate R. , Arnould John P. Y. , Bejder Lars
Published: October 2016

An animal's body condition will affect its survival and reproductive success, which influences population dynamics. Despite its importance, relatively little is known about the body condition of large whales and its relationship to reproduction. We assessed the body condition of humpback whales (Megaptera novaeangliae) at a breeding/resting ground from aerial photographs recorded using an unmanned aerial vehicle (UAV). Photogrammetry methods were used to measure the surface area of individual whales, which was used as an index for body condition. Repeated measurements of the same individuals were not possible; hence, this study represents a cross‐sectional sample of the population. Intraseasonal changes in the body condition of four reproductive classes (calves, immature, mature, and lactating) were investigated to infer the relative energetic cost that each class faces during the breeding season. To better understand the costs of reproduction, we investigated the relationship between female body condition (FBC) and the linear growth and body condition of their dependent calves (CBC). We documented a linear decline in the body condition of mature whales (0.027 m2/d; n = 20) and lactating females (0.032 m2/d; n = 31) throughout the breeding season, while there was no change in body condition of immature whales (n = 51) and calves (n = 32). The significant decline in mature and lactating female's body condition implies substantial energetic costs for these reproductive classes. In support of this, we found a positive linear relationship between FBC and CBC. This suggests that females in poorer body condition may not have sufficient energy stores to invest as much energy into their offspring as better conditioned females without jeopardizing their own body condition and survival probability. Measurement precision was investigated from repeated measurements of the same animals both from the same and different photographs, and by looking at residual errors in relation to the positioning of the whales in the photographs. The resulting errors were included in a sensitivity analysis to demonstrate that model parameters were robust to measurement errors. Our findings provide strong support for the use of UAVs as a noninvasive tool to measure the body condition of whales and other mammals.