Mapping of land use and geomorphology in the APAPORE project area by LANDSAT satellite data, volume 1

The results of a land use and geomorphological mapping of the so-called Projeto APAPORE area, at Mato Grosso do Sul State are presented. The study was carried out using multispectral scanner (MSS) and return beam vidicon LANDSAT images (channels 5 and 7 for the MSS) at the scale of 1:250,000 from 1980 through visual interpretation. The results indicate that pastureland is the most widespead class and that the agricultural areas re concentrated in the north of the area under study. The area covered with cerradao (arboreous savanna type) has a great areal extention, thus permitting the advance of the agricultural frontier. The geomorphological mapping can be useful to regional planning of future land use within the studied area

An evaluation of the performance of chemistry transport models by comparison with research aircraft observations. Part 1: Concepts and overall model performance

A rigorous evaluation of five global Chemistry-Transport and two Chemistry-Climate Models operated by several different groups in Europe, was performed. Comparisons were made of the models with trace gas observations from a number of research aircraft measurement campaigns during the four-year period 1995-1998. Whenever possible the models were run over the same four-year period and at each simulation time step the instantaneous tracer fields were interpolated to all coinciding observation points. This approach allows for a very close comparison with observations and fully accounts for the specific meteorological conditions during the measurement flights. This is important considering the often limited availability and representativity of such trace gas measurements. A new extensive database including all major research and commercial aircraft measurements between 1995 and 1998, as well as ozone soundings, was established specifically to support this type of direct comparison. Quantitative methods were applied to judge model performance including the calculation of average concentration biases and the visualization of correlations and RMS errors in the form of so-called Taylor diagrams. We present the general concepts applied, the structure and content of the database, and an overall analysis of model skills over four distinct regions. These regions were selected to represent various atmospheric conditions and to cover large geographical domains such that sufficient observations are available for comparison. The comparison of model results with the observations revealed specific problems for each individual model. This study suggests the further improvements needed and serves as a benchmark for re-evaluations of such improvements. In general all models show deficiencies with respect to both mean concentrations and vertical gradients of important trace gases. These include ozone, CO and NOx at the tropopause. Too strong two-way mixing across the tropopause is suggested to be the main reason for differences between simulated and observed CO and ozone values. The generally poor correlations between simulated and measured NOx values suggest that in particular the NOx input by lightning and the convective transport from the polluted boundary layer are still not well described by current parameterizations, which may lead to significant differences in the spatial and seasonal distribution of NOx in the models. Simulated OH concentrations, on the other hand, were found to be in surprisingly good agreement with measured values

An evaluation of the performance of chemistry transport models - Part 2: Detailed comparison with two selected campaigns

This is the second part of a rigorous model evaluation study involving five global Chemistry-Transport and two Chemistry-Climate Models operated by different groups in Europe. Simulated trace gas fields were interpolated to the exact times and positions of the observations to account for the actual weather conditions and hence for the specific histories of the sampled air masses. In this part of the study we focus on a detailed comparison with two selected campaigns, PEM-Tropics A and SONEX, contrasting the clean environment of the tropical Pacific with the more polluted North Atlantic region. The study highlights the different strengths and weaknesses of the models in accurately simulating key processes in the UT/LS region including stratosphere-troposphere-exchange, rapid convective transport, lightning emissions, radical chemistry and ozone production. Model simulated Radon, which was used as an idealized tracer for continental influence, was occasionally much better correlated with measured CO than simulated CO pointing towards deficiencies in the used biomass burning emission fields. The abundance and variability of HOx radicals is in general well represented in the models as inferred directly from the comparison with measured OH and HO2 and indirectly from the comparison with hydrogen peroxide concentrations. Components of the NOy family such as PAN, HNO3 and NO were found to compare less favorably. Interestingly, models showing good agreement with observations in the case of PEM-Tropics A often failed in the case of SONEX and vice versa. A better description of NOx and NOy emissions, chemistry and sinks is thought to be key to future model improvements with respect to the representation of chemistry in the UT/LS region

Integrated genomic analyses identify ARID1A and ARID1B alterations in the childhood cancer neuroblastoma

Neuroblastomas are tumors of peripheral sympathetic neurons and are the most common solid tumor in children. To determine the genetic basis for neuroblastoma we performed whole-genome sequencing (6 cases), exome sequencing (16 cases), genome-wide rearrangement analyses (32 cases), and targeted analyses of specific genomic loci (40 cases) using massively parallel sequencing. On average each tumor had 19 somatic alterations in coding genes (range, 3–70). Among genes not previously known to be involved in neuroblastoma, chromosomal deletions and sequence alterations of chromatin remodeling genes, ARID1A and ARID1B, were identified in 8 of 71 tumors (11%) and were associated with early treatment failure and decreased survival. Using tumor-specific structural alterations, we developed an approach to identify rearranged DNA fragments in sera, providing personalized biomarkers for minimal residual disease detection and monitoring. These results highlight dysregulation of chromatin remodeling in pediatric tumorigenesis and provide new approaches for the management of neuroblastoma patients

Aviation Fuel Tracer Simulation: Model Intercomparison and Implications

An upper limit for aircraft-produced perturbations to aerosols and gaseous exhaust products in the upper troposphere and lower stratosphere (UT/LS) is derived using the 1992 aviation fuel tracer simulation performed by eleven global atmospheric models. Key Endings are that subsonic aircraft emissions: (1) have not be responsible for the observed water vapor trends at 40 deg N; (2) could be a significant source of soot mass near 12 km, but not at 20 km; (3) might cause a noticeable increase in the background sulfate aerosol surface area and number densities (but not mass density) near the northern mid-latitude tropopause; and (4) could provide a global, annual mean top of the atmosphere radiative forcing up to +0.006 W/sq m and -0.013 W/sq m due to emitted soot and sulfur, respectively

Serviços ecológicos de insetos e outros artrópodes em sistemas agroflorestais.

Com a crescente demanda global por alimentos há aumento do impacto ambiental das atividades para produção animal e agrícola sobre a biodiversidade, ocasionando redução cada vez mais acentuada de insetos e artóprodes. Porém, os serviços ecológicos fornecidos pela biodiversidade podem ser importantes para a produção sustentável de alimentos em sistemas agroflorestais. Nessa revisão bibliográfica objetivou-se elucidar como insetos e artrópodes podem ser benéficos em sistemas de produção agropecuários, em especial sistemas agroflorestais (SAFs). A diversidade desses organismos auxilia na conservação e preservação do meio ambiente dentro e no entorno desse tipo de uso da terra. Além disso, pesquisas científicas constataram que o nicho ecológico de insetos e outros tipos de artrópodes são essencialmente importantes para a ciclagem de nutrientes e manutenção da sustentabilidade e produção dos agroecossistemas. As monoculturas, quando comparadas com sistemas agroflorestais, provocam significativas perdas de biodiversidade, inclusive de insetos. Portanto, a exploração de sistemas agroflorestais em consonância com a preservação do meio ambiente e aproveitando seus serviços ecológicos pode ser uma alternativa sutentável para áreas de produção agrícola

Brazilian Satellite Remote Sensing program selected recent applications

Applications in the areas of agronomy, geology, oceanography, geography, environment and cartography are presented. A brief description of the Brazilian program is also given

Influence of aviation fuel composition on the formation and lifetime of contrails — a literature review

The question of how aviation fuel composition affects the formation and lifetime of contrails is a complex one. Although the theory regarding initial contrail formation is well-founded in thermodynamics and proven to be correct by measurements, there remain large uncertainties in terms of persistent contrails forming contrail cirrus. These originate both from processes which are not yet fully understood and from the complexity of quantifying the many factors of influence on their effect on climate. There is an extended cause-effect chain from fuel composition through its combustion and consequential emissions, to contrail formation and their spreading in the atmosphere, and microphysical and optical properties. These properties affect the lifetime and radiative effect of single contrails to the global and multi-annual average of the radiative effects of all contrails, and thus eventually to their climate impact. This problem extends over 17 orders of magnitude in space and time, from the scales of single molecules (about 0.1 nm) and their elementary interactions (say, 1 ns) to the global scales of climate (say, 10,000 km and 10-30 years). It is not possible to cover such a vast range with a single numerical model or with relatively few measurements

Circulating tumor DNA guided adjuvant chemotherapy in stage II colon cancer (MEDOCC-CrEATE):study protocol for a trial within a cohort study

BACKGROUND: Accurate detection of patients with minimal residual disease (MRD) after surgery for stage II colon cancer (CC) remains an urgent unmet clinical need to improve selection of patients who might benefit form adjuvant chemotherapy (ACT). Presence of circulating tumor DNA (ctDNA) is indicative for MRD and has high predictive value for recurrent disease. The MEDOCC-CrEATE trial investigates how many stage II CC patients with detectable ctDNA after surgery will accept ACT and whether ACT reduces the risk of recurrence in these patients. METHODS/DESIGN: MEDOCC-CrEATE follows the 'trial within cohorts' (TwiCs) design. Patients with colorectal cancer (CRC) are included in the Prospective Dutch ColoRectal Cancer cohort (PLCRC) and give informed consent for collection of clinical data, tissue and blood samples, and consent for future randomization. MEDOCC-CrEATE is a subcohort within PLCRC consisting of 1320 stage II CC patients without indication for ACT according to current guidelines, who are randomized 1:1 into an experimental and a control arm. In the experimental arm, post-surgery blood samples and tissue are analyzed for tissue-informed detection of plasma ctDNA, using the PGDx elio™ platform. Patients with detectable ctDNA will be offered ACT consisting of 8 cycles of capecitabine plus oxaliplatin while patients without detectable ctDNA and patients in the control group will standard follow-up according to guideline. The primary endpoint is the proportion of patients receiving ACT when ctDNA is detectable after resection. The main secondary outcome is 2-year recurrence rate (RR), but also includes 5-year RR, disease free survival, overall survival, time to recurrence, quality of life and cost-effectiveness. Data will be analyzed by intention to treat. DISCUSSION: The MEDOCC-CrEATE trial will provide insight into the willingness of stage II CC patients to be treated with ACT guided by ctDNA biomarker testing and whether ACT will prevent recurrences in a high-risk population. Use of the TwiCs design provides the opportunity to randomize patients before ctDNA measurement, avoiding ethical dilemmas of ctDNA status disclosure in the control group. TRIAL REGISTRATION: Netherlands Trial Register: NL6281/NTR6455 . Registered 18 May 2017, https://www.trialregister.nl/trial/6281