Western Spruce Budworm and Wildfire: Is There a Connection?

In the interior Pacific Northwest, extensive defoliation of mixed conifer forests during outbreaks of western spruce budworm (WSB) may leave the visual impression of a tinderbox with trees primed to burst into flame. But is this the case? We addressed this question with funding from the USDA/U.S. Department of the Interior Joint Fire Science Program (project 09– 1–06–5). Here we summarize our three recent publications exploring the potential relationship between WSB outbreaks and fire. We used a multimethod approach to explore potential disturbance interactions that might cause one disturbance to change the occurrence or severity of the other. We used tree-ring records to see whether WSB and fire are related in time and computer modeling to see how defoliation could affect crown fire behavior

Fluid-membrane tethers: minimal surfaces and elastic boundary layers

Thin cylindrical tethers are common lipid bilayer membrane structures, arising in situations ranging from micromanipulation experiments on artificial vesicles to the dynamic structure of the Golgi apparatus. We study the shape and formation of a tether in terms of the classical soap-film problem, which is applied to the case of a membrane disk under tension subject to a point force. A tether forms from the elastic boundary layer near the point of application of the force, for sufficiently large displacement. Analytic results for various aspects of the membrane shape are given.Comment: 12 page

Haloes gone MAD: The Halo-Finder Comparison Project

[abridged] We present a detailed comparison of fundamental dark matter halo properties retrieved by a substantial number of different halo finders. These codes span a wide range of techniques including friends-of-friends (FOF), spherical-overdensity (SO) and phase-space based algorithms. We further introduce a robust (and publicly available) suite of test scenarios that allows halo finder developers to compare the performance of their codes against those presented here. This set includes mock haloes containing various levels and distributions of substructure at a range of resolutions as well as a cosmological simulation of the large-scale structure of the universe. All the halo finding codes tested could successfully recover the spatial location of our mock haloes. They further returned lists of particles (potentially) belonging to the object that led to coinciding values for the maximum of the circular velocity profile and the radius where it is reached. All the finders based in configuration space struggled to recover substructure that was located close to the centre of the host halo and the radial dependence of the mass recovered varies from finder to finder. Those finders based in phase space could resolve central substructure although they found difficulties in accurately recovering its properties. Via a resolution study we found that most of the finders could not reliably recover substructure containing fewer than 30-40 particles. However, also here the phase space finders excelled by resolving substructure down to 10-20 particles. By comparing the halo finders using a high resolution cosmological volume we found that they agree remarkably well on fundamental properties of astrophysical significance (e.g. mass, position, velocity, and peak of the rotation curve).Comment: 27 interesting pages, 20 beautiful figures, and 4 informative tables accepted for publication in MNRAS. The high-resolution version of the paper as well as all the test cases and analysis can be found at the web site http://popia.ft.uam.es/HaloesGoingMA

NT-proBNP for Risk Prediction in Heart Failure:Identification of Optimal Cutoffs Across Body Mass Index Categories

OBJECTIVES The goal of this study was to assess the predictive power of N-terminal pro–B-type natriuretic peptide (NT-proBNP) and the decision cutoffs in heart failure (HF) across body mass index (BMI) categories. BACKGROUND  Concentrations of NT-proBNP predict outcome in HF. Although the influence of BMI to reduce levels of NT-proBNP is known, the impact of obesity on prognostic value remains uncertain. METHODS Individual data from the BIOS (Biomarkers In Heart Failure Outpatient Study) consortium were analyzed. Patients with stable HF were classified as underweight (BMI = 40 kg/m(2)) obese. The prognostic rote of NT-proBNP was tested for the endpoints of all-cause and cardiac death. RESULTS The study population included 12,763 patients (mean age 66 +/- 12 years; 25% women; mean left ventricular ejection fraction 33% 113%). Most patients were overweight (n = 5,176), followed by normal weight (n = 4,299), mildly obese (n = 2,157), moderately obese (n = 612), severely obese (n = 314), and underweight (n = 205). NT-proBNP inversely correlated with BMI (beta = -0.174 for 1 kg/m(2); P < 0.001). Adding NT-proBNP to clinical models improved risk prediction across BMI categories, with the exception of severely obese patients. The best cutoffs of NT-proBNP for 5-year all-cause death prediction were lower as BMI increased (3,785 ng/L, 2,193 ng/L, 1,554 ng/L, 1,045 ng/L, 755 ng/L, and 879 ng/L, for underweight, normal weight, overweight, and mildly, moderately, and severely obese patients, respectively) and were higher in women than in men. CONCLUSIONS NT-proBNP maintains its independent prognostic value up to 40 kg/m(2) BMI, and tower optimal risk-prediction cutoffs are observed in overweight and obese patients

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Relationships Between Moisture, Chemistry, and ignition of Pinus contorta Needles During the Early Stages of Mountain Pine Beetle Attack

Very little is known about how foliar moisture and chemistry change after a mountain pine beetle attack and even less is known about how these intrinsic foliar characteristics alter foliage ignitability. Here, we examine the fuel characteristics and ignition potential of Pinus contorta (lodgepole pine) foliage during the early stages of a mountain pine beetle attack. Foliar samples were taken periodically from multiple trees identified as green (healthy, unattacked), recently attacked, or red (dead). The fuel moisture con- tent, chemical composition, and time to ignition of needles from each attack category were quantified. Foliar moisture contents varied by an order of magnitude between the attack categories and were lowest for red needles (�12% on average), highest for green needles (�109% on average), and most variable for needles of recently attacked trees. Dry matter proportions of fiber in the needles of attacked and red trees were nearly twice that of green needles. Starch and sugar levels were much lower in the needles of attacked and red trees than green trees. Crude fat contents also differed between the attack categories. Time to ignition was strongly related to time since beetle attack. Ignition times varied from as little as 11 s for red needles to 41 s for green needles. A combined model of foliar moisture content, fiber, and crude fat explained 92% of the variation in the foliar time to ignition. Results show that decreased mois- ture contents and changes in foliar chemistry increase the foliar flammability of mountain pine beetle- attacked trees. This suggests that less heat would be required to ignite the foliage of attacked trees and thus crown fire potential may be higher in attacked stands as long as foliage is retained on the tree. Published by Elsevier B.V

ANZCCSG BabyBrain99; intensified systemic chemotherapy, second look surgery and involved field radiation in young children with central nervous system malignancy

BACKGROUND: ANZCCSG BabyBrain99 is a trial of intensive systemic chemotherapy with dual stem cell supported treatment, second look surgery and involved field radiation for children less than four years of age with malignant central nervous system tumours. PROCEDURE: Following primary resection, treatment included two courses of cisplatin and oral etoposide, a third course of mobilising chemotherapy (vincristine, etoposide, cyclophosphamide) with stem cell harvest, followed by intensive stem cell supported chemotherapy with high dose cyclophosphamide, etoposide and vincristine. Children were evaluated for second resection before proceeding to a second stem cell supported consolidation therapy consisting of melphalan and carboplatin. Patients then received involved field radiation therapy. RESULTS: Thirty three children with a range of diagnoses were enrolled. Nine percent of children had metastatic disease at diagnosis. Eighteen children completed treatment including irradiation. At the end of induction the event free survival was 70% (54-86). Forty eight percent of children had a complete response, 18% had stable disease and 3% had a partial response. Five year overall survival was 40% (22-56) and event free survival was 33% (17-50). Children in whom a complete resection were achieved had a significantly superior outcome compared to those children without a complete resection, 5 year EFS 60% (45-75), as compared to 22% (13-30), P-value &lt;0.05. CONCLUSIONS: BabyBrain99 confirms that intensive stem cell supported chemotherapy can be safely administered to infants with CNS tumours however overall prognosis remains poor. Importantly, the study reinforces a complete surgical resection as an important favourable prognostic indicator