bluuebunny/crossref_metadata_2025_split huggingface dataset:
Catheter ablation of left posterior fascicular ventricular tachycardia in children with limited fluoroscopy exposure
Authors: Koca Serhat , Akdeniz Celal , Karacan Mehmet , Tuzcu Volkan 
Published: June 2019

AbstractIntroduction:Catheter ablation of left posterior fascicular ventricular tachycardia in the pediatric population remains challenging, and most studies about this topic have been conducted on adult patients. This study aimed to assess the clinical presentation features and outcomes of catheter ablations performed using limited fluoroscopy with three-dimensional electroanatomic mapping system guidance in a pediatric left posterior fascicular ventricular tachycardia patient group.Methods:A total of 20 consecutive patients undergoing left posterior fascicular ventricular tachycardia ablation at a single tertiary centre were enrolled. All children with left posterior fascicular ventricular tachycardia underwent electrophysiological studies using the EnSite NavX system guidance. Ablations were performed during the sinus rhythm based on the Purkinje potentials in all patients.Results:The mean patient age was 12.7 years (range 2–16), and the mean patient weight was 51 kg (range 11–84). The mean procedure and median fluoroscopy times were 143.1 minutes and 3.4 minutes, respectively. No fluoroscopy was used in three patients. Acute success was achieved in 19 patients (95%). During a mean follow-up of 38.6 ± 19.35 months, left posterior fascicular ventricular tachycardia recurred in four patients (20%). Repeat ablations were performed successfully in those patients who developed recurrences. No complications were seen.Conclusions:Catheter ablation of left posterior fascicular ventricular tachycardia in children can be performed safely and effectively with low fluoroscopy exposure using a three-dimensional electroanatomic mapping system.
Inferring substrate preferences from test morphology in echinoids, and interpreting spatial and temporal patterns of diversity
Authors: Carter Burchard D. 
Published: June 2019

Preservational style of fossil echinoid tests allows assessment of the likelihood of post-mortem transport out of the preferred sediment type of the living echinoid. Sedimentologic study of the matrix of untransported specimens allows a check on functional morphologic inferences of the species' preferred sediment types. Functional morphologic analysis allows inference of a species preferred sediment type because the petals, fasciolaes, tubercles, ambulacral pores, ambulacral shape, and test profile control the echinoid's ability to burrow, and the grain size of sediment into which it is capable of doing so. Past studies have achieved better than 90% accuracy in predicting the grain size of thin sections of rocks containing echinoids, simply by interpretation of their functional morphology. Most mistaken predictions are attributable to species living in sediments that are less difficult to burrow in (sands) than those to which they are adapted (muds). Other species may live in sediments in which they are not well adapted by assuming an epifaunal mode of life.Relative proportions of species in an echinoid fauna preferring various sediment grain sizes, plotted for each of a number of localities, has proven useful in inferring generalized facies patterns within regions.Plots of temporal changes in echinoid species diversity through time correspond well to changes in proportions of species inferred to have preferred various substrate conditions, suggesting an environmental and taphonomic component to simple diversity curves.
Echinoderm phylogeny: how congruent are morphological and molecular estimates?
Authors: Smith Andrew B. 
Published: June 2019

Single data sets, whether derived from morphological or molecular evidence, provide one-off estimates of the correct phylogeny. Their reliability can only be gauged by statistical approaches such as bootstrapping or clade decay, but these test only whether there are sufficient characters in the data matrix to justify the groupings identified. They do not test whether the characters themselves are reliable. Consequently, confidence in the correctness of phylogenetic interpretations comes primarily from discovering the same (or statistically indistinguishable) patterns from independent data sets.Congruence studies are most advanced for echinoids, where four independent data sets (two morphological and two molecular) provide strong corroboration for a single phylogenetic scheme. Analysis of all four data sets combined generates a highly robust hypothesis of relationships. The situation is very different for asteroids. Two analyses based on morphological data have reached very different conclusions. Three independent molecular data sets also have been compiled, but none has a statistically reliable signal concerning higher taxon relationships. Even combining all three molecular data sets fails to generate a statistically robust solution, implying that the major lines of asteroids diverged rapidly from one another. For ophiuroids, both morphological and molecular data generate topologies that for the most part lack statistical robustness. There is currently no cladistic analysis of holothurian relationships based on morphological data, and only a few taxa have been sequenced. The molecular data is, however, congruent and does permit an initial assessment of relationships. Nothing definite can be deduced about crinoid relationships since even fewer molecular sequences are known and morphological analysis remains sketchy.Class-level relationships derived from two morphological and two molecular data sets also show considerable congruence, though a single definitive solution has yet to emerge.
Introduction to Radiometric Dating
Authors: Miller Brent V. 
Published: June 2019

Radiometric dating of rocks and minerals to constrain the age of the Earth, timing of geological events and paleobiological histories has its roots in the works of nuclear physicists of the early Nineteenth Century during the period of discovery of radioactivity and investigations into the nature of the atom. The intervening years since have seen great progress in using the long-lived radioactive elements to constrain the origin and evolution of the Earth and to place the rock and fossil record into a consistent, numerically quantifiable temporal framework.U-Th-Pb and40Ar/39Ar dating methods have emerged as the primary tools for calibrating most of Earth history. It is important for all geoscientists to appreciate the physical basis underlying these methods and to have the ability to evaluate dates by means of currently accepted practices of data presentation. This introduction, along with the accompanying chapters, is intended to help the consumers of radiometric dates to understand better the uses and limitations of radiometric dating methods in an effort to tailor methods and techniques to address specific geochronologic needs, including calibration of the geologic time scale.The ultimate goal of a fully calibrated rock record remains an on-going endeavor. The 2004 ICS geologic time scale is the latest compilation of those efforts. The numerical age calibration is constrained by only 213 radiometric dates, the vast majority of which are U-Pb and40Ar/39Ar dates. Radiometric age control is not evenly distributed through geologic time. There are virtually no radiometric dates in the late Cenozoic where magnetostratigraphy and cyclostratigraphic methods are more precise and applicable. Radiometric dating efforts are concentrated on biostratigraphically important segments of the rock record such as the Permian-Triassic and Cretaceous-Paleocene boundary events, and this is reflected in high-precision calibration of these boundaries. Large segments of geologic time, however, are constrained by either a few radiometric dates per chronostratigraphic unit (most of the Paleozoic) or none at all (Upper Triassic). The current status of radiometric age control on the rock record largely reflects real, underlying scientific issues in biostratigraphy and geochronology, and thus can help point the way to fruitful lines of collaboration between paleontologists, stratigraphers, and geochronologists.
Applications of Commonly Used Numerical Techniques in Diatom-Based Paleoecology
Authors: Cumming Brian F. , Moser Katrina A. 
Published: June 2019

Applications of commonly used numerical techniques in diatom-based paleoecology are reviewed including: approaches used to model diatom taxa to important limnological variables; ordination and other commonly used multivariate approaches; and the myriad of approaches that are now being explored to infer environmental variables based on diatom assemblages.Modelling the response of individual diatom taxa to limnologically important variables is consistent with ecological theory and has been largely accomplished using approaches based on generalized linear models. These techniques have established that strong and significant relationships exist between the numerically dominant diatom taxa and important limnological variables (e.g., pH, nutrients, salinity). Null modelling approaches have also been used. However, inclusion of rare taxa in null models results in high rates of type-II errors, and consequently spurious claims that only a minority of diatoms have significant relationships to important limnological variables such as lakewater pH and nutrients.A variety of ordination techniques are widely used in diatom-based paleolimnological studies to aid in summarizing the main directions of variation in diatom assemblages, and to identify limnological variables that are strongly correlated to the diatom assemblages, both in time and space. More advanced ordination techniques, such as partial ordinations, are increasingly being used to assess the shared and unique variance attributable to groups of important limnological variables. Further, diatom-based approaches based on experimental designs with control lakes and appropriate multivariate statistics are now becoming increasingly common to assess, for example, the impact of forestry on water quality.A number of different diatom-based inference models based on the present-day relationships between diatom assemblages and limnological variables are now available for inferring important limnological variables. These approaches vary from simple approaches such as weighted-averaging to more complex approaches involving curve fitting and maximum likelihood, neural networks, and Bayesian statistics. All of these approaches have been shown to result in strong inference models, each using aspects of ecological information available from the diatom assemblages.
Fundamental Needs
Authors: Thomson Garrett 
Published: June 2019

The concept of need is promising and alluring because of three factors:1. Needs are objective because it is a discoverable matter of fact what needs a person has and yet this fact has a bearing on what one ought to do. The concept is both factual and evaluative.2. Needs are matters of priority; what we need usually overrides other reasons for action.3. Needs are unimpeachable values. We cannot say truly that a person ought to have different needs and, in this sense, they are fundamental.In this paper, I shall be concerned primarily with explaining the third of these features. I am interested in fundamental needs, but not necessarily basic or minimal needs, such as those pertaining to survival. Furthermore, I shall not be concerned directly in the strength of claims to need on other people, but rather on oneself. I shall use ‘need’ in such a way that the term indicates a disposition and does not imply a lack. I need food even when I am eating.
The use of alkanes as markers for estimating diet composition in sheep and goats
Authors: Ferreira L.M.M. , Oliván M. , Rodrigues M.A.M. , Dias-da-Silva A. , Osoro K. 
Published: June 2019

SummaryAn experiment was carried out to evaluate the use of alkanes for estimating diet composition of goats and sheep offered three different dietary treatments. Twelve animals as two groups of 4 crossbred goats (G1, 24 kg live weight; G2, 22 kg) and 4 crossbred sheep (S, 26 kg live weight), were housed in metabolism pens. Animals were offered daily a total of 1 kg DM/100 kg live weight. G1 received 70% ryegrass (Lolium perenne) and 30% gorse (Ulex gallii), G2 received 70% ryegrass and 30% heather (Erica sp.) and S group ate 100% ryegrass. Diet composition was estimated from the alkane concentrations (using all alkanes from C23 to C36 or only odd-chain alkanes C27, C29, C31 and C33) in diet and faeces (with or without correction for incomplete faecal recoveries) using least-squares procedures.Dietary treatment and animal species significantly affected alkane faecal recoveries, except for C24 and C36. When applying the faecal recovery corrections, there were no significant differences between measured proportions of dietary components and those estimated using all alkanes or odd-chain alkanes. In contrast, the proportions calculated without faecal recovery correction differed significantly (P<0.05) from the actual proportions and over-estimated the amount in the diet of those plant components with higher concentrations of long-chain alkanes (Erica sp. and Lolium perenne). The results indicate that alkanes are useful markers to estimate diet composition, however, it was observed that animal species and diet composition influenced the faecal recovery of alkanes. This suggests that the use of the alkane methodology for estimating the diet selection of grazing animals should be preceded by a calculation of the actual alkane faecal recoveries for each experimental condition.
Gas production and dry matter degradability of diets for ruminants
Authors: Bovera F. , Calabrò S. , Schettini R. , Cutrignelli M.I. , Infascelli F. , Piccolo V. 
Published: June 2019

SummaryFour feeds widely used in ruminant nutrition (corn silage, alfalfa hay, corn grain and soybean meal) and nine diets prepared in the laboratory by thorough mixing of these four feeds in different ratios, were analysed for: chemical composition according to the Weende and Van Soest schemes. Starch content, as well as total gas production and dry matter degradability after 8, 24 and 48 hours of incubation were measured. The same parameters were calculated for the nine diets from the measurements made on each of the four components (i.e. estimated values). For the chemical determinations, the differences between the analytical results (real values) and the corresponding estimated values varied little and did not reach statistical significance. However, statistically significant differences (P<0.05) between real and estimated values appeared for gas production at 24 hours (48.07 vs. 44.13 ml/200mg DM) and for DM degradability after 8 hours of incubation (32.35 vs. 30.56 %). The differences in the gas production measurements were removed when Diet 1 was excluded.
A new strategy for the in situ technique through the use of one fistulated ruminant
Authors: Sampaio I. B. M. , Tomich T. R. 
Published: June 2019

SummaryThe sampling of forage from distinct sites in the pasture and which are then dried and ground separately as replicates for the in sacco technique, is the best procedure for studies of forage evaluation. It permits the evaluation of the true error (variation between blocks of plants) and not the variation between replicates obtained from only one sample of forage dried, ground and then divided between distinct nylon bags (which causes an underestimation of error). Consequently it is possible with only one ruminant to define an experimental design which is simpler, but capable of offering better precision.
Comparison between in vitro gas production and in situ degradation for evaluating rumen dry matter degradation of maize grain and tropical grasses
Authors: Mauricio R. M. , Tomich T.R. , Filho R. A. , Reis R. B. , Gonçalves L.C. , Borges I. , Dhanoa M. S. 
Published: June 2019

SummaryThe in situ technique (NB) was compared to the in vitro gas production technique (Gas) in terms of ability to estimate the dry matter degradation (DMD) using high soluble substrates (maize grains) and low soluble substrates (four tropical forages). The experiments (in situ and in vitro) were carried out at the same time using the same cow for both techniques and DMD was estimated at 6, 12, 24, 48 & 96 h. The results showed that DMD from Gas were lower than NB DMD and the correlation for the maize group were lower than those of the grass group which indicated that Gas technique, closed system, has potential to analyse highly soluble substrates, probably, overcoming the particle losses effect demonstrated by the in situ technique.
Fermentation kinetics of the carbohydrate fraction of fresh forage, silage and hay of Avena sativa
Authors: Calabrò S. , Bovera F. , Zicarelli F. , Tudisco R. , Cutrignelli M.I. , Piccolo G. , Infascelli F. 
Published: June 2019

SummaryThe aim of the present paper was to study the fermentation characteristics and kinetics of the carbohydrate fractions of fresh, ensiled and hay of oats (Avena sativa) using the Cornell Net Carbohydrate and Protein System (CNCPS) and the in vitro gas production technique (GPT). The whole forage and its NDF and EIR (ethanol insoluble residue) fractions were incubated in order to estimate the fermentation kinetics of carbohydrate fractions (A, B1 and B2) with the curve subtraction method. The carbohydrates fermentation kinetics estimated with the GPT agree with the three CNCPS carbohydrate fractions and explain some modification due to forage preservation methods. For all forages, the fermentation rate of the three CNCPS carbohydrate fractions showed the same ranking A > B1 > B2. Fermentation rate value (RM: 0.163, 0.057, 0.032 h-1 A, B1, B2 fraction for fresh oats; 0.106, 0.032, 0.016 h-1 for A, B1, B2 fractions of ensiled oats; 0.165, 0.051, 0.022 h-1 A, B1, B2 fraction for oats hay) could be used as kd in the CNCPS.
A Methodological approach in La Reunion Island on the value of faecal Near Infrared Reflectance Spectroscopy (NIRS) to assess grazing intake and diet quality of the dairy cow
Authors: Decruyenaere V. , J.Bony  , Grimaud P. , Lecomte Ph. 
Published: June 2019

SummaryTo test the applicability of faecal NIRS to real conditions, an experimental approach was undertaken across several representative dairy farms (N = 30) located ‘La Réunion’ island. From an ongoing survey, this approach consists to characterize the nutritional value of all feeds (grazed fresh forage, hay, silages and supplementary feeds) offered to the lactating herds, and to predict ingested diet from faecal NIRS models previously developed on a large experimental sheep faeces reference data-base.The methodological objective was to evaluate if such a spectral database could be a useful reference to estimate dairy cow total dry matter intake and diet quality, and so predict the grazed grass intake with reasonable accuracy. According to preliminary results, the NIRS estimated total intake varied between 13.7 and 19 kg DM/day and in vivo organic matter digestibility ranged from 51.7 to 74.8 % with an averaged value of 66 %. The estimated grass intake varied between 0 to nearly 10 kg DM/d. On a spectral basis, dairy cows faeces were quite different from the sheep faeces reference database, with an averaged standardised distance (H) upper of 3.0 (H = 9.1; Hmin = 2.08 – Hmax = 19.22) but predicted intake appeared valid. Indeed, according to the feeding value of diets and lactating cow requirements, the NIRS predicted total intakes were well correlated to the level of milk production. Moreover, for four particular situations, the fresh grass was cut, distributed at the trough and total intake really measured. The correlation between predicted and measured values was high with R2 = 0.94 and standard error of regression = 0.469 kg DM/d. These initial results appear quite encouraging, although the methodology is still exploratory and needs to be validated across a larger set of data. As a low cost and rapid prediction technique, NIRS appears to be a potential methodology that could find many useful developments in the improvement of the knowledge of forage use in tropical conditions.
Genetic aspects of condition score, heart girth and milk-yield traits in Italian Friesian cows
Authors: Gallo L. , Carnier P. , Cassandro M. , Dal Zotto R. , Bittante G. 
Published: June 2019

AbstractFunctional traits related to costs are currently of interest for selection and management of dairy cattle. The present study was aimed to estimate heritability for body condition score (BCS) and heart girth (HG), to investigate the genetic relationships between BCS, HG and milk-yield traits using a test-day model and to analyse the consistency of the estimates in different lactation stages. Cows from 25 dairy herds were scored for BCS and measured for HG at 3-month intervals for 2 years. Approximately 5000 test-day observations on BCS, HG and milk fat and protein yield from 1429 Italian Friesian cows were analysed using two approaches: (1) repeated observations were treated as repeated measurements of the same trait, both within and across lactations; (2) observations collected in different stages of lactation (dry period, 1 to 75 days in milk (DIM), 76 to 130 DIM, 131 to 210 DIM, 211 to 300 DIM) were treated as different traits. (Co)variance components and related parameters were estimated using REML multiple-trait procedures and unequal design animal models.Heritability estimates (approach 1) for fat and protein test-day yield, BCS and HG were 0.22, 0.18, 0.29 and 0.33, respectively. BCS was negatively correlated with yield traits (-0.43 and -0.48 for fat and protein yield, respectively) but positively correlated (0.33) with HG. Genetic relationships between HG and milk-yield traits were negligible. Heritability estimates (approach 2) were 0.28 and 0.27 for BCS recorded in the first half of lactation (1 to 75 and 76 to 130 DIM, respectively), 0.36 for BCS measured on cows in the second half of lactation and 0.32 for BCS recorded on dry cows. Heritability estimates for HG in different lactation stages ranged from 0.31 to 0.40. Genetic correlations between BCS measured in different lactation stages were generally high (0.85 or more), with the exception of the correlation between the first and the last stage of lactation (0.74) and of the relationships between the beginning of lactation and the dry period (0.7). Genetic correlations between HG measured in different lactation stages were mostly higher than 0.80.