bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oceanographic influences on the distribution and relative abundance of market squid paralarvae (Doryteuthis opalescens) off the Southern and Central California coast
Authors: Van Noord Joel E. , Dorval Emmanis 
Published: June 2017

AbstractMarket squid (Doryteuthis opalescens) are ecologically and economically important to the California Current Ecosystem, but populations undergo dramatic fluctuations that greatly affect food web dynamics and fishing communities. These population fluctuations are broadly attributed to 5–7‐years trends that can affect the oceanography across 1,000 km areas; however, monthly patterns over kilometer scales remain elusive. To investigate the population dynamics of market squid, we analysed the density and distribution of paralarvae in coastal waters from San Diego to Half Moon Bay, California, from 2011 to 2016. Warming local ocean conditions and a strong El Niño event drove a dramatic decline in relative paralarval abundance during the study period. Paralarval abundance was high during cool and productive La Niña conditions from 2011 to 2013, and extraordinarily low during warm and eutrophic El Niño conditions from 2015 to 2016 over the traditional spawning grounds in Southern and Central California. Market squid spawned earlier in the season and shifted northward during the transition from cool to warm ocean conditions. We used a general additive model to assess the variability in paralarval density and found that sea surface temperature (SST), zooplankton displacement volume, the log of surface chlorophyll‐a, and spatial and temporal predictor variables explained >40% of the deviance (adjusted r2 of .29). Greatest paralarval densities were associated with cool SST, moderate zooplankton concentrations and low chlorophyll‐a concentrations. In this paper we explore yearly and monthly trends in nearshore spawning for an economically important squid species and identify the major environmental influences that control their population variability.
Explaining island‐wide geographical patterns of Caribbean fish diversity: A multi‐scale seascape ecology approach
Authors: Sekund Linn , Pittman Simon 
Published: June 2017

AbstractGeographical patterning of fish diversity across coral reef seascapes is driven by many interacting environmental variables operating at multiple spatial scales. Identifying suites of variables that explain spatial patterns of fish diversity is central to ecology and informs prioritization in marine conservation, particularly where protection of the highest biodiversity coral reefs is a primary goal. However, the relative importance of conventional within‐patch variables versus the spatial patterning of the surrounding seascape is still unclear in the ecology of fishes on coral reefs. A multi‐scale seascape approach derived from landscape ecology was applied to quantify and examine the explanatory roles of a wide range of variables at different spatial scales including: (i) within‐patch structural attributes from field data (5 × 1 m2 sample unit area); (ii) geometry of the seascape from sea‐floor maps (10–50 m radius seascape units); and wave exposure from a hydrodynamic model (240 m resolution) for 251 coral reef survey sites in the US Virgin Islands. Non‐parametric statistical learning techniques using single classification and regression trees (CART) and ensembles of boosted regression trees (TreeNet) were used to: (i) model interactions; and (ii) identify the most influential environmental predictors from multiple data types (diver surveys, terrain models, habitat maps) across multiple spatial scales (1–196,350 m2). Classifying the continuous response variables into a binary category and instead predicting the presence and absence of fish species richness hotspots (top 10% richness) increased the predictive performance of the models. The best CART model predicted fish richness hotspots with 80% accuracy. The statistical interaction between abundance of living scleractinian corals measured by SCUBA divers within 1 m2 quadrats and the topographical complexity of the surrounding sea‐floor terrain (150 m radius seascape unit) measured from a high‐resolution terrain model best explained geographical patterns in fish richness hotspots. The comparatively poor performance of models predicting continuous variability in fish diversity across the seascape could be a result of a decoupling of the diversity‐environment relationship owing to structural degradation leading to a widespread homogenization of coral reef structure.
Phytoplankton subsidies to the inter‐tidal zone are strongly affected by surf‐zone hydrodynamics
Authors: Shanks Alan L. , Sheesley Peter , Johnson Leyia 
Published: June 2017

AbstractThe size of bottom‐up subsidies, food and larvae, from the ocean has a profound impact on inter‐tidal communities and populations. Alongshore variations in subsidies are attributed to variation in coastal conditions, but also might be due to variations in surf‐zone hydrodynamics. We tested this hypothesis by comparing surf‐zone phytoplankton concentrations to surf‐zone hydrodynamics as indicated by the width of the surf zones. To minimize the potential effects of alongshore variation in phytoplankton abundance in the coastal ocean, we sampled closely spaced sites (median separation 1 km) over short periods (3 days). Surf‐zone concentrations of coastal phytoplankton taxa (e.g. Chaetoceros spp., Pseudo‐nitzschia spp. and dinoflagellates) varied with surf‐zone width; 65% to 94% of the variability in their concentration is explained by surf‐zone width. Where surf zones were narrow and more reflective, phytoplankton concentrations were one to several orders of magnitude lower than in wider, more dissipative surf zones. The most closely spaced stations were 30 m apart, but represented distinct habitats – a reflective and a more dissipative surf zone. Phytoplankton concentrations in the reflective surf zone were an order of magnitude or more lower than in the adjacent more dissipative surf zone. A reanalysis of a published study on phytoplankton subsidies found similar results. Alongshore variation in surf‐zone hydrodynamics appears to be an important driver of phytoplankton subsidies to the inter‐tidal zone.
Off‐reef planktivorous reef fishes respond positively to decadal‐scale no‐take marine reserve protection and negatively to benthic habitat change
Authors: Russ Garry R. , Aller‐Rojas Oscar D. , Rizzari Justin R. , Alcala Angel C. 
Published: June 2017

AbstractThe effects of no‐take marine reserve (NTMR) protection and changes in benthic habitat on fusiliers (family Caesionidae) were investigated at four small Philippine offshore islands on time scales of 10–31 years. Fusiliers are highly mobile, schooling, medium‐sized planktivorous fish that generally feed “off‐reef.” For these reasons, and given the small size of the NTMRs (3.6–37.5 ha) in this study, it was predicted that fusilier density would be unlikely to show clear effects of NTMR protection, or to respond to changes in benthic habitat. In contrast to predictions, clear NTMR effects were observed on fusilier density at three of the four NTMRs, with durations of protection from 14 to 31 years. Furthermore, the study provided strong evidence that benthic variables, specifically cover of live hard coral and dead substratum, affect the density of fusiliers. This effect of benthic habitat on density was highlighted by several major environmental disturbances that caused shifts in the benthic habitat from live hard coral to dead substratum. For two of the three most abundant species of fusiliers individually, and for all three of them combined (Pterocaesio pisang + Caesio caerulaurea + Pterocaesio digramma/tessellata), as live hard coral cover decreased, fish density decreased. It is hypothesized that these “off‐reef” daytime feeders may have such a strong association with live hard coral cover because they use this habitat as nocturnal sleeping sites. Multivariate analyses indicated that, across all sites and times sampled, cover of live hard coral and dead substratum accounted for 38% of the variation in fish assemblage structure. These results are important as there are very few reports in the published literature of strong effects of NTMR protection or changes in benthic habitat on the density and assemblage structure of fusiliers.
A biogeographical perspective on the variation in mouse lemur density throughout Madagascar
Authors: Setash Casey M. , Zohdy Sarah , Gerber Brian D. , Karanewsky Caitlin J. 
Published: June 2017

Abstract

Madagascar is home to the smallest primates in the world, the mouse lemurs (Microcebus species). Twenty‐four species of mouse lemur are currently recognised and are found in variable ecosystems, from dry forests and spiny deserts to humid forests. Due to their widespread distribution and the large number of sympatric species, mouse lemurs can be used as a model to understand the linkages among species richness, population density, and habitat. As all lemurs are threatened by habitat loss and fragmentation, this information can also be used to inform conservation management.

We hypothesise that on an island‐wide scale, we will find higher population densities in western dry forests than in eastern humid forests because the western dry forests exhibit lower species richness, more sympatric habitat use, and lower resource stability than the eastern humid forests.

We conducted a literature review of population density estimates of known mouse lemur species, and used those data to conduct a meta‐analysis and estimate overall average population density by geographic region.

Our findings suggest that mouse lemur species living in western dry forest generally exhibit higher densities than those in eastern humid forests. This may be partly explained by higher habitat fragmentation in western dry forests, where species co‐occur, but is likely to be a function of the magnitude and variability in seasonally available resources in each forest type. Higher seasonality results in less constant food availability and lower levels of environmental predictability, fostering species capable of coping with environmental change and maintaining high densities throughout periods of resource paucity.

Our study highlights the importance of conducting Microcebus population density research that adheres to standardised methodological approaches. We point to the need for population density estimates for several species for which data are lacking. Such knowledge is important to assess the conservation status of these species, but also to enhance our ability to identify the macro‐biogeographical and local ecological drivers of interspecific and intraspecific variability in population density.
A life‐cycle approach to species barriers
Authors: Johannesson Kerstin 
Published: June 2017

What maintains reproductive barriers between closely related species is, of course, of fundamental interest to a closer understanding of the mechanisms that generate new biodiversity. One important dichotomy is to separate barriers evolved from divergent selection over environmental gradients (extrinsic barriers) from barriers caused by incompatibilities between different genetic arrangements that may have evolved in isolation (intrinsic barriers). This dichotomy also reflects an important applied consequence. As the extrinsic barriers are associated with specific environmental contexts, they may be partly or completely erased if the environment changes. In contrast, intrinsic barriers are inert to the environmental context and resistant to environmental changes. From a conservation biology perspective, it may thus be important to be able to separate extrinsic and intrinsic species barriers, but this may in many organisms be a complex matter. In this issue of Molecular Ecology, Montecinos et al. () found a tractable approach that works for species with life cycles that include two reproductive but ecologically similar generations, one haploid and the other diploid. What they demonstrate is that using a life‐cycle approach offers a unique possibility to separate between prezygotic and postzygotic barriers. Indeed, in the case of an isomorphic life cycle, there is even a possibility to suggest whether postzygotic barriers are more likely to be intrinsic or extrinsic. In this way, their approach may be useful both to increase our understanding of the basic mechanisms of speciation and to single out when species barriers will better resist environmental changes.
Dispersal, isolation and diversification with continued gene flow in an Andean tropical dry forest
Authors: Toby Pennington R. , Lavin Matt 
Published: June 2017

The Andes are the world's longest mountain chain, and the tropical Andes are the world's richest biodiversity hot spot. The origin of the tropical Andean cordillera is relatively recent because the elevation of the mountains was relatively low (400–2500 m palaeoelevations) only 10 MYA with final uplift being rapid. These final phases of the Andean orogeny are thought to have had a fundamental role in shaping processes of biotic diversification and biogeography, with these effects reaching far from the mountains themselves by changing the course of rivers and deposition of mineral‐rich Andean sediments across the massive Amazon basin. In a recent issue of Molecular Ecology, Oswald, Overcast, Mauck, Andersen, and Smith (2017) investigate the biogeography and diversification of bird species in the Andes of Peru and Ecuador. Their study is novel in its focus on tropical dry forests (Figure 1) rather than more mesic biomes such as rain forests, cloud forests and paramos, which tend to be the focus of science and conservation in the Andean hot spot. It is also able to draw powerful conclusions via the first deployment of genomic approaches to a biogeographic question in the threatened dry forests of the New World.
Exploring the bark thickness–stem diameter relationship: clues from lianas, successive cambia, monocots and gymnosperms
Authors: Rosell Julieta A. , Olson Mark E. , Anfodillo Tommaso , Martínez‐Méndez Norberto 
Published: June 2017

Summary

Bark thickness is ecologically crucial, affecting functions from fire protection to photosynthesis. Bark thickness scales predictably with stem diameter, but there is little consensus on whether this scaling is a passive consequence of growth or an important adaptive phenomenon requiring explanation.

With a comparative study across 913 species, we test the expectation that, if bark thickness–stem diameter scaling is adaptive, it should be possible to find ecological situations in which scaling is predictably altered, in this case between species with different types and deployments of phloem.

‘Dicots’ with successive cambia and monocots, which have phloem‐free bark, had predictably thinner inner (mostly living) bark than plants with single cambia. Lianas, which supply large leaf areas with limited stem area, had much thicker inner bark than self‐supporting plants. Gymnosperms had thicker outer bark than angiosperms.

Inner bark probably scales with plant metabolic demands, for example with leaf area. Outer bark scales with stem diameter less predictably, probably reflecting diverse adaptive factors; for example, it tends to be thicker in fire‐prone species and very thin when bark photosynthesis is favored. Predictable bark thickness–stem diameter scaling across plants with different photosynthate translocation demands and modes strongly supports the idea that this relationship is functionally important and adaptively significant.
Type III metacaspases: calcium‐dependent activity proposes new function for the p10 domain
Authors: Klemenčič Marina , Funk Christiane 
Published: June 2017

Summary

Metacaspases are a subgroup of caspase homologues represented in bacteria, algae and plants. Although type I and type II metacaspases are present in plants, recently discovered and uncharacterized type III metacaspases can only be found in algae which have undergone secondary endosymbiosis.

We analysed the expression levels of all 13 caspase homologues in the cryptophyte Guillardia theta in vivo and biochemically characterized its only type III metacaspase, GtMC2, in vitro.

Type III metacaspase GtMC2 was shown to be an endopeptidase with a preference for basic amino acids in the P1 position, which exhibited specific N‐terminal proteolytic cleavage for full catalytic efficiency. Autolytic processing, as well as the activity of the mature enzyme, required the presence of calcium ions in low millimolar concentrations. In GtMC2, two calcium‐binding sites were identified, one with a dissociation constant at low and the other at high micromolar concentrations.

We show high functional relatedness of type III metacaspases to type I metacaspases. Moreover, our data suggest that the low‐affinity calcium‐binding site is located in the p10 domain, which contains a well‐conserved N‐terminal region. This region can only be found in type I/II/III metacaspases, but is absent in calcium‐independent caspase homologues.
Utilizing three‐dimensional data in orthodontic practice and research
Authors: Solem R. C. 
Published: June 2017

AbstractThe recent prevalence of three dimensional (3D) images of soft and hard tissues provides a wealth of new data from which the clinician can evaluate these changes. However, evaluating this new data presents new and significant challenges. Current approaches utilizing multi‐dimensional data for the precise evaluation of changes related to treatment and growth sets are reviewed. The results of current validation studies exploring approaches to these problems are reviewed, including the registration of longitudinal data using maxillary and mandibular regions of reference. Challenges related to the consistent selection of points on complex three‐dimensional structures are circumvented using an automated, shape analysis based approach. Imaging using these new modalities yields a tremendous amount of data. Analysis of large data sets from cross‐sectional studies with multiple variables are simplified using a principle components analysis, from which a reduced set of variables is constructed. Examples of this approach are presented. The use of advanced methods to process and interpret data from 3D imaging modalities highlights critical aspects of craniofacial growth and form.
Moving towards precision orthodontics: An evolving paradigm shift in the planning and delivery of customized orthodontic therapy
Authors: Jheon A. H. , Oberoi S. , Solem R. C. , Kapila S. 
Published: June 2017

AbstractAdvances in precision medicine portend similar progress in orthodontics and will be increasingly harnessed to achieve customized treatment approaches and enhance treatment efficiencies. Our goal is to provide a background on emerging advances in computer technologies and biomedicine and highlight their current and likely future applications to precision orthodontics. A review of orthodontically relevant technologies and advances in pertinent biological research was undertaken. Innovations in computer hardware and software, and 3D imaging technologies offer the ability for customized treatment and biomechanical planning that will be more fully realized within the next few decades. These technologies combined with 3D printing are already being applied to customized appliance fabrication such as aligners and retainers. The future prospects for custom fabrication of orthodontic brackets of appropriate material properties and smart devices are highly desirable and compelling goals. Within biomedicine, the fundamental understanding of cartilage growth and bone biology is currently being tested in animal models to modify mandibular growth and modulate tooth movement, respectively. Some of these discoveries will ultimately have clinical applications in orthodontics including for growth modification, accelerating orthodontic tooth movement, and enhancing anchorage or retention of teeth. Additional genomic and proteomic information will add to further customization of orthodontic diagnosis and treatments. Over the coming decades, precision orthodontics will continue to benefit from advances in many fields and will require the integration of advances in technology, and biomedical and clinical research to deliver optimal, efficient, safe, and reproducible personalized orthodontic treatment.
Jaw mechanics in dolichofacial and brachyfacial phenotypes: A longitudinal cephalometric‐based study
Authors: Iwasaki L. R. , Liu Y. , Liu H. , Nickel J. C. 
Published: June 2017

Structured AbstractObjectivesTo determine whether dolichofacial (Frankfort horizontal mandibular plane angle (FHMPA) ≥30°) vs brachyfacial (FHMPA ≤22°) phenotypes differ in temporomandibular joint (TMJ) loads and whether these differences correlate longitudinally with mandibular ramus height (Condylion‐Gonion, Co‐Go).Setting and Sample PopulationLateral and posteroanterior cephalographs from ten dolichofacial and ten brachyfacial individuals made at average ages of 6 (T1), 12 (T2) and 18 (T3) years and available online (http://www.aaoflegacycollection.org/aaof_home.html) were used.Materials and MethodsThree‐dimensional anatomical data were derived from cephalographs and used in numerical models to predict TMJ loads for a range of biting angles on incisors, canines and first molars. Two criteria were used to define clinically important between‐group TMJ load differences: statistical significance was defined with a two‐group t‐test, and where differences were also ≥20%. A statistical approach called response surface analysis was used to assess correlation between TMJ loads and its predictors considered in this study.ResultsThe two phenotypes had significantly different FHMPA at all ages (P<.05). No differences in TMJ loads were found at T1. Ipsilateral and contralateral TMJ loads at T2 and T3 were significant and ≥20% larger in dolichofacial than brachyfacial phenotypes for specific biting angles (all adjusted P<.05). Regression analysis indicated age and ramus height contribute 53% of the variability in normalized values of TMJ loads. At higher ages, dolichofacial phenotypes had significantly higher TMJ loads which were correlated with shorter ramus heights compared to brachyfacial phenotypes.ConclusionsCraniofacial mechanics may explain, in part, mandibular growth differences between dolichofacial and brachyfacial phenotypes.
Osteogenic potential of three different autogenous bone particles harvested during implant surgery
Authors: Liang C , Lin X , Wang S‐L , Guo L‐H , Wang X‐Y , Li J 
Published: June 2017

ObjectivesThe aim was to compare the osteoblast activity and osteogenic potential of autogenous bone particles harvested using three different techniques and determine the most advantageous method of collecting autogenous bone particles.Subjects and MethodsBone particles were harvested from 20 patients during dental implant surgery using bone scraping, low‐speed drilling and bone trap filtering. After the osteoblasts were cultured, cell proliferation, migration, mineralization, transcription of osteogenesis‐related genes, secretion of osteogenesis‐related proteins and osteoinductive protein content in the bone particle matrix were evaluated.ResultsOsteoblast activity and osteogenic potential were higher in bone samples harvested by scraper or low‐speed drilling than in samples harvested by bone trap filter. Although these parameters were slightly lower in the low‐speed drilling group than in the scraper group, significant differences were found only in bone Gla protein levels. However, the levels of osteoinductive proteins in the bone particle matrix were significantly higher in the low‐speed drilling group than in the scraper group.ConclusionsLow‐speed drilling is a recommendable and effective technique for collecting autogenous bone particles. In implant operations, low‐speed drilling can be considered the first‐line option, and if the quantity of harvested bone is insufficient, bone shavings obtained by the scraper may be considered.