LONG-TERM OVERSTORY VEGETATION RESPONSES TO PRESCRIBED FIRE MANAGEMENT FOR LONGLEAF PINE AT BIG THICKET NATIONAL PRESERVE

At the western edge of the longleaf pine (Pinus palustris) range, federal land managers have burned the forests of Big Thicket National Preserve to bring back the structure and diversity of the longleaf pine forest. In the early 1990’s, a four year study was conducted by Rice University, and the National Park Service continued monitoring the study’s fire ecology research plots. After two decades of data collection, ordination was applied to species abundance data to examine changes in vegetation communities from a variety of prescribed fire treatments and controls. The vegetation data was separated by size class to include overstory, small tree, sapling, and seedling data. Across the size classes and treatments, the sandhill and wetland savanna vegetation types remained less effected by fire treatments and only the upland pine responded to changes in the overstory. Although fire management had an effect on vegetation types, upon reviewing prescribed histories, it became evident that prescribed fire alone was not changing vegetation communities to foster longleaf pine habitat. Most of the plots did not have longleaf pine trees or seedlings present and two plots that were mechanically treated showed distinction among other treatment regimes. Restoration treatments including the mechanical and chemical application and seedling plantings are necessary to ensure restoration of the longleaf pine forest structure and diverse understory vegetation

LONG-TERM OVERSTORY VEGETATION RESPONSES TO PRESCRIBED FIRE MANAGEMENT FOR LONGLEAF PINE AT BIG THICKET NATIONAL PRESERVE

At the western edge of the longleaf pine (Pinus palustris) range, federal land managers have burned the forests of Big Thicket National Preserve to bring back the structure and diversity of the longleaf pine forest. In the early 1990’s, a four year study was conducted by Rice University, and the National Park Service continued monitoring the study’s fire ecology research plots. After two decades of data collection, ordination was applied to species abundance data to examine changes in vegetation communities from a variety of prescribed fire treatments and controls. The vegetation data was separated by size class to include overstory, small tree, sapling, and seedling data. Across the size classes and treatments, the sandhill and wetland savanna vegetation types remained less effected by fire treatments and only the upland pine responded to changes in the overstory. Although fire management had an effect on vegetation types, upon reviewing prescribed histories, it became evident that prescribed fire alone was not changing vegetation communities to foster longleaf pine habitat. Most of the plots did not have longleaf pine trees or seedlings present and two plots that were mechanically treated showed distinction among other treatment regimes. Restoration treatments including the mechanical and chemical application and seedling plantings are necessary to ensure restoration of the longleaf pine forest structure and diverse understory vegetation

Responses to Prescribed Fire at Big Thicket National Preserve, Texas, USA

US Federal land managers have utilized hand ignited prescribed fire at Big Thicket National Preserve in efforts to restore the structure and diversity of the longleaf pine (Pinus palustris) forest. A fire ecology study was initiated by Rice University in the early 1990’s and the National Park Service has continued monitoring the plots. Ordination was applied to species abundance data to examine changes in vegetation communities from a variety of prescribed fire treatments and controls. The vegetation data was separated by size class to include overstory, small tree, large sapling and seedling data. Across the size classes and treatments, the sandhill and wetland savanna vegetation types remained less effected by fire treatments and only the upland pine responded to changes in the overstory. Upon reviewing fire return interval histories, it became evident that prescribed fire alone was not changing vegetation communities. Most of the plots did not have longleaf pine trees or seedlings present and only two plots that were mechanical treated showed distinction among other treatment regimes. Restoration treatments including the mechanical and chemical application and seedling plantings are necessary to ensure restoration of the longleaf pine forest structure and diverse understory vegetation

Ground-based, Near-infrared Exospectroscopy. II. Tentative Detection of Emission From the Extremely Hot Jupiter WASP-12b

We report the tentative detection of the near-infrared emission of the Hot Jupiter WASP-12b with the low-resolution prism on IRTF/SpeX. We find a K-H contrast color of 0.137% +/- 0.054%, corresponding to a blackbody of temperature 2400 (+1500/-500) K and consistent with previous, photometric observations. We also revisit WASP-12b's energy budget on the basis of secondary eclipse observations: the dayside luminosity is a relatively poorly constrained (2.0-4.3) x 10^30 erg/s, but this still allows us to predict a day/night effective temperature contrast of 200-1,000 K (assuming A_B=0). Thus we conclude that WASP-12b probably does not have both a low albedo and low recirculation efficiency. Our results show the promise and pitfalls of using single-slit spectrographs for characterization of extrasolar planet atmospheres, and we suggest future observing techniques and instruments which could lead to further progress. Limiting systematic effects include the use of a too-narrow slit on one night -- which observers could avoid in the future -- and chromatic slit losses (resulting from the variable size of the seeing disk) and variations in telluric transparency -- which observers cannot control. Single-slit observations of the type we present remain the best option for obtaining lambda > 1.7 micron spectra of transiting exoplanets in the brightest systems. Further and more precise spectroscopy is needed to better understand the atmospheric chemistry, structure, and energetics of this, and other, intensely irradiated planet.Comment: ApJ accepted. 16 pages, 15 figure

Protocol for an observational study to identify potential predictors of an acute exacerbation in patients with chronic obstructive pulmonary disease (the PACE Study).

INTRODUCTION: Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are the most critical events for patients with COPD that have a negative impact on patients' quality of life, accelerate disease progression, and can result in hospital admissions and death. Although there is no distinct definition or detailed knowledge about AECOPD, it is commonly used as primary outcome in clinical studies. Furthermore, it may be difficult in clinical practice to differentiate the worsening of symptoms due to an AECOPD or to the development of heart failure. Therefore, it is of major clinical importance to investigate the underlying pathophysiology, and if possible, predictors of an AECOPD and thus to identify patients who are at high risk for developing an acute exacerbation. METHODS AND ANALYSIS: In total, 355 patients with COPD will be included prospectively to this study during a 3-week inpatient pulmonary rehabilitation programme at the Schoen Klinik Berchtesgadener Land, Schoenau am Koenigssee (Germany). All patients will be closely monitored from admission to discharge. Lung function, exercise tests, clinical parameters, quality of life, physical activity and symptoms will be recorded, and blood samples and exhaled air will be collected. If a patient develops an AECOPD, there will be additional comprehensive diagnostic assessments to differentiate between cardiac, pulmonary or cardiopulmonary causes of worsening. Follow-up measures will be performed at 6, 12 and 24 months.Exploratory data analyses methods will be used for the primary research question (screening and identification of possible factors to predict an AECOPD). Regression analyses and a generalised linear model with a binomial outcome (AECOPD) will be applied to test if predictors are significant. ETHICS AND DISSEMINATION: This study has been approved by the Ethical Committee of the Philipps University Marburg, Germany (No. 61/19). The results will be presented in conferences and published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT04140097

Studien zur Hochschuldidaktik und zur Lehrerausbildung

SIGLECopy held by FIZ Karlsruhe / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Correct positioning of central venous catheters in pediatrics. Are current formulae really useful?

Correct positioning of a central venous catheter (CVC) tip in pediatric patients is very important. Malpositioning may lead to direct complications, such as arrhythmia and increase the risk of thrombosis, infections, valve failures or pericardial tamponade. The aim of this review was to identify and summarize published formulae for the correct positioning of the CVC tip in children and to discuss the benefits of these formulae for the daily routine. A systematic and standardized search in Medline and PubMed was performed to identify published formulae. Formulae for insertion depth of the CVC tip over the right internal jugular vein are discussed. The keywords pediatric or pediatric, children, central venous catheter, CVC, central venous, length, insertion, optimal, formula, depth, correct position and right position, internal jugular vein were used to identify the formulae. A total of 854 publications were found and 127 publications were analyzed. The publications were subsequently assessed and classified independently by a specialist in anesthesiology and a specialist in pediatrics. A total of six publications described different body height-based formulae for calculation of a CVC insertion depth. No prospective evaluation of these formulae was performed to show if it is possible to place a CVC tip at the optimal position. The benefit of a formula for daily practice is very limited due to the problem of choosing the right insertion point. The recommended insertion depth should be considered as an indicator and a verification of the CVC tip position should be done using an imaging technique

Estimation of the optimal tube length. Systematic review article on published formulae for infants and children

The correct placement of an endotracheal tube in children is essential as incorrect placement following unilateral ventilation and tube displacement may lead to far-reaching consequences, such as volutrauma and hypoxia, respectively. Different formulae referring to the correct placement of nasotracheal and orotracheal tubes have been published with reference to body weight and age. The aim of the present review article was to identify and compare the published formulae for estimating correct endotracheal tube placement in children with their advantages and disadvantages. A search in Medline and PubMed was performed to identify published formulae. Formulae for insertion depth in orotracheal and also nasotracheal intubation are discussed. The published formulae for newborns and infants are presented separately. The keywords paediatric/pediatric, anaesthesia/anesthesia, anaesthesiology/anesthesiology, endotracheal tube, placement, position, length, depth and insertion were used to identify the formulae. A total of 806 publications were found, 16 publications were identified as being relevant and 13 different formulae were identified. In the age group from 1 to 16 years old a total of 7 formulae (6 age-based formulae and one based on weight) and for newborns and infants a total of 6 formulae (4 formulae based on body weight, 1 formula based on body length and 1 formula based on gestational age) were found. All publications were subsequently assessed and classified independently by a specialist physician in anesthesiology and a specialist physician in pediatrics. The published formulae were comparatively simply to apply but had notable limitations. Correlating the position of the endotracheal tubes with chest x-rays, the concordance analysis showed that for the age-based formulae using orotracheal as well as nasotracheal intubation and in both age groups, an accordance could only be achieved in a maximum of 81 %. In the presence of a lack of alternative possibilities, only one formula based on the gestational age seemed to have an impact on estimation of correct endotracheal tube depth placement in newborns and infants. Therefore, a generally valid formula cannot be recommended without verification by auscultation or chest x-ray

Formula-based calculation of the tube size for preclinical emergency medicine

Incorrect placement of the endotracheal tube in newborns and infants following unilateral ventilation and accidental extubation may lead to deleterious consequences, such as volutrauma or hypoxia. The aim of the present study was to identify and compare the published formulas in order to estimate the correct endotracheal tube placement in children. Aim of the present study was to identify and compare the published formulas by searching PubMedA (R) and MEDLINEA (R) in order to estimate the correct endotracheal tube placement in children. Formulas on oro- and nasotracheal intubation depth were discussed. Formulas published for newborns and infants were presented separately. The keywords paediatric/pediatric, anaesthesia/anesthesia, anaesthesiology/anesthesiology, endotracheal tube, placement, position, length, depth and insertion were used. Publications and formulas were assessed and classified by two independent colleagues. In the specified timeframe, a total of N = 806 publications were reviewed, of which 16 were considered relevant. 13 different formulas could be identified: for children from 1-16 years we found six age-related formulas and one formula based on the patient's weight. For newborns and infants we found four formulas using the patient's weight and one formula using the patient's length. One formula was based on the gestational age. Publications and formulas were assessed and classified by two independent colleagues. Among the formulas based on age, an exact match of both groups was seen in only 81 %, both for oro- and for nasotracheal intubation. For prehospital pediatric emergencies, no universal and all-embracing formula can be recommended. Only one formula based on the gestational age seems to have substantial impact. Especially for decisions that have to be taken under time pressure, a reliably implementable formula is indispensable