Supporting Spartina: Interdisciplinary perspective shows Spartina as a distinct solid genus

In 2014, a DNA-based phylogenetic study confirming the paraphyly of the grass subtribe Sporobolinae proposed the creation of a large monophyletic genus Sporobolus, including (among others) species previously included in the genera Spartina, Calamovilfa, and Sporobolus. Spartina species have contributed substantially (and continue contributing) to our knowledge in multiple disciplines, including ecology, evolutionary biology, molecular biology, biogeography, experimental ecology, biological invasions, environmental management, restoration ecology, history, economics, and sociology. There is no rationale so compelling to subsume the name Spartina as a subgenus that could rival the striking, global iconic history and use of the name Spartina for over 200 yr. We do not agree with the subjective arguments underlying the proposal to change Spartina to Sporobolus. We understand the importance of both the objective phylogenetic insights and of the subjective formalized nomenclature and hope that by opening this debate we will encourage positive feedback that will strengthen taxonomic decisions with an interdisciplinary perspective. We consider that the strongly distinct, monophyletic clade Spartina should simply and efficiently be treated as the genus Spartina

Factors Associated with Revision Surgery after Internal Fixation of Hip Fractures

Background: Femoral neck fractures are associated with high rates of revision surgery after management with internal fixation. Using data from the Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) trial evaluating methods of internal fixation in patients with femoral neck fractures, we investigated associations between baseline and surgical factors and the need for revision surgery to promote healing, relieve pain, treat infection or improve function over 24 months postsurgery. Additionally, we investigated factors associated with (1) hardware removal and (2) implant exchange from cancellous screws (CS) or sliding hip screw (SHS) to total hip arthroplasty, hemiarthroplasty, or another internal fixation device. Methods: We identified 15 potential factors a priori that may be associated with revision surgery, 7 with hardware removal, and 14 with implant exchange. We used multivariable Cox proportional hazards analyses in our investigation. Results: Factors associated with increased risk of revision surgery included: female sex, [hazard ratio (HR) 1.79, 95% confidence interval (CI) 1.25-2.50; P = 0.001], higher body mass index (fo

Particle methods for maximum likelihood estimation in latent variable models

Standard methods for maximum likelihood parameter estimation in latent variable models rely on the Expectation-Maximization algorithm and its Monte Carlo variants. Our approach is different and motivated by similar considerations to simulated annealing; that is we build a sequence of artificial distributions whose support concentrates itself on the set of maximum likelihood estimates. We sample from these distributions using a sequential Monte Carlo approach. We demonstrate state of the art performance for several applications of the proposed approach

Using Phenology to Optimize Timing of Mowing and Grazing Treatments for Medusahead (Taeniatherum caput-medusae)

The invasive annual grass medusahead (Taeniatherum caput-medusae [L.] Nevski) poses a substantial threat to the health and function of rangelands across the western United States. On rangelands containing other desirable annual grasses, selective control of medusahead is difficult as this invasive species has traits similar to those of desired species. One key trait that differs between medusahead and other annual grasses is the rate and timing of phenological development. In this study we define management states for medusahead on the basis of the patterns of variation of forage palatability and susceptibility of seed production to defoliation over phenological stages. We integrate these management states with field observations to model the rates and timing of phenology-based management states to identify when targeted grazing or mowing treatments are most appropriate using Dirichlet regression and multistate modeling. While defoliation at any phenological stage from V3 (boot) to R8 (milk stage) was effective in reducing medusahead seed head production, clipping after anthesis almost eliminated seed production. However, the observed decline in crude protein at this point (11-8%) suggests that the transition from R4 (emergence of awns) to R5 (anthesis) is also the point at which medusahead becomes both unpalatable and not adequately nutritious to livestock. As a consequence there was a window of 10 to 15 days when 90% or more of medusahead reproductive tillers are susceptible to grazing but could also support nutritional needs of cattle and sheep to prevent avoidance in diet selection. In contrast, the window of opportunity for mowing, on average, extended for about 35 days. In a given year, the timing in which different medusahead populations entered each phenological stage varied at both the landscape and pasture scale, which creates both challenges and opportunities in using grazing animals and other defoliation mechanisms to control medusahead. © 2017 The Society for Range Management.The Rangeland Ecology & Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information

Influência da temperatura e do tempo de armazenamento nas dosagens bioquímicas de uréia e creatinina em soro ou plasma caninos Effect of temperature and storage time on urea and creatinine dosages from canine serum or plasma

O trabalho teve como objetivos avaliar algumas condições de estocagem de soro e de plasma com EDTA 10% utilizados para determinação dos valores de uréia e creatinina em cães, e avaliar a possibilidade de substituir o soro pelo plasma conservado com EDTA 10%. Foram realizadas 3600 análises (1800 amostras de soro e 1800 de plasma) com amostras que permaneceram em temperaturas ambiente, de refrigeração e de congelamento. As análises foram realizadas imediatamente após a obtenção da amostra (tempo 0) e após 2, 6, 12, 24, 72 horas e 30 e 60 dias após a coleta do sangue. Os resultados permitiram concluir que a uréia conservou-se por mais tempo na amostra sérica refrigerada até 30 dias e a creatinina na amostra sérica congelada até 72h. O soro mostrou mais estabilidade que o plasma em todas as condições de estoque estabelecidas.<br>Aiming to evaluating some conditions of EDTA 10% serum and plasma storage for urea and creatinine values determinations in canines as well as analyzing the possibility of serum substitution by plasma, a total of 3600 samples (1800 serum and 1800 of plasma) were analyzed at room, refrigeration and freezing temperatures. Different time intervals were used in the analysis: immediately after sampling (time 0), and at 2, 6, 12, 24, and 72 hours, and 30 and 60 days after the blood collection. The data showed that urea remains conserved for more time in the refrigerated serum sample until 30 days and the creatinine in the frozen serum sample until 72 hours. Serum showed more stability than plasma in all storage conditions established

Slab to back-arc to arc: fluid and melt pathways through the mantle wedge beneath the Lesser Antilles

Volatiles expelled from subducted plates promote melting of the overlying warm mantle, feeding arc volcanism. However, debates continue over the factors controlling melt generation and transport, and how these determine the placement of volcanoes. To broaden our synoptic view of these fundamental mantlewedge processes, we image seismic attenuation beneath the Lesser Antilles arc, an end-member system that slowly subducts old, tectonized lithosphere. Punctuated anomalies with high ratios of bulk-to-shear attenuation (Qκ-1/Qμ-1 &gt; 0.6) and VP/VS (&gt;1.83) lie 40 km above the slab, representing expelled fluids that are retained in a cold boundary layer, transporting fluids toward the back-arc. The strongest attenuation (1000/QS ∼ 20), characterizing melt in warm mantle, lies beneath the back-arc, revealing how back-arc mantle feeds arc volcanoes. Melt ponds under the upper plate and percolates toward the arc along structures from earlier back-arc spreading, demonstrating how slab dehydration, upper-plate properties, past tectonics, and resulting melt pathways collectively condition volcanism.</p

Supporting Spartina: Interdisciplinary perspective shows Spartina as a distinct solid genus

In 2014, a DNA-based phylogenetic study confirming the paraphyly of the grass subtribe Sporobolinae proposed the creation of a large monophyletic genus Sporobolus, including (among others) species previously included in the genera Spartina, Calamovilfa, and Sporobolus. Spartina species have contributed substantially (and continue contributing) to our knowledge in multiple disciplines, including ecology, evolutionary biology, molecular biology, biogeography, experimental ecology, biological invasions, environmental management, restoration ecology, history, economics, and sociology. There is no rationale so compelling to subsume the name Spartina as a subgenus that could rival the striking, global iconic history and use of the name Spartina for over 200 yr. We do not agree with the subjective arguments underlying the proposal to change Spartina to Sporobolus. We understand the importance of both the objective phylogenetic insights and of the subjective formalized nomenclature and hope that by opening this debate we will encourage positive feedback that will strengthen taxonomic decisions with an interdisciplinary perspective. We consider that the strongly distinct, monophyletic clade Spartina should simply and efficiently be treated as the genus Spartina