Integrating remote sensing datasets into ecological modelling: a Bayesian approach

Process-based models have been used to simulate 3-dimensional complexities of forest ecosystems and their temporal changes, but their extensive data requirement and complex parameterisation have often limited their use for practical management applications. Increasingly, information retrieved using remote sensing techniques can help in model parameterisation and data collection by providing spatially and temporally resolved forest information. In this paper, we illustrate the potential of Bayesian calibration for integrating such data sources to simulate forest production. As an example, we use the 3-PG model combined with hyperspectral, LiDAR, SAR and field-based data to simulate the growth of UK Corsican pine stands. Hyperspectral, LiDAR and SAR data are used to estimate LAI dynamics, tree height and above ground biomass, respectively, while the Bayesian calibration provides estimates of uncertainties to model parameters and outputs. The Bayesian calibration contrasts with goodness-of-fit approaches, which do not provide uncertainties to parameters and model outputs. Parameters and the data used in the calibration process are presented in the form of probability distributions, reflecting our degree of certainty about them. After the calibration, the distributions are updated. To approximate posterior distributions (of outputs and parameters), a Markov Chain Monte Carlo sampling approach is used (25 000 steps). A sensitivity analysis is also conducted between parameters and outputs. Overall, the results illustrate the potential of a Bayesian framework for truly integrative work, both in the consideration of field-based and remotely sensed datasets available and in estimating parameter and model output uncertainties

The Lithium Depletion Boundary and the Age of the Young Open Cluster IC~2391

We have obtained new photometry and intermediate resolution ($\Delta \lambda = 2.7$ \AA\ ) spectra of 19 of these objects (14.9 $\le$ $I_c$ $\le$ 17.5) in order to confirm cluster membership. We identify 15 of our targets as likely cluster members based on their $VRI$ photometry, spectral types, radial velocity, and H$\alpha$ emission strengths. Higher S/N spectra were obtained for 8 of these probable cluster members in order to measure the strength of the lithium 6708 \AA\ doublet and thus obtain an estimate of the cluster's age. One of these 8 stars has a definite lithium detection and two other (fainter) stars have possible lithium detections. A color-magnitude diagram for our program objects shows that the lithium depletion boundary in IC~2391 is at $I_c$=16.2. Using recent theoretical model predictions, we derive an age for IC~2391 of 53$\pm$5 Myr. While this is considerably older than the age most commonly attributed for this cluster ($\sim$35 Myr) this result for IC~2391 is comparable those recently derived for the Pleiades and Alpha Persei clusters and can be explained by new models for high mass stars that incorporate a modest amount of convective core overshooting.Comment: ApJ Letters, acccepte

Microtubule disrupting N-phenyl-N’-(2-chloroethyl) ureas display anticancer activity on cell adhesion, P-glycoprotein and BCL-2-mediated drug resistance

Objective: Our research program has focused on the development of promising, soft alkylating N-phenyl-N’-(2-chloroethyl)urea (CEU) compounds which acylate the glutamic acid-198 of β-tubulin, near the binding site of colchicum alkaloids. CEUs inhibit the motility of cancerous cells in vitro and, interestingly, exhibit antiangiogenic and anticancer activity in vivo. Mitotic arrest induced by microtubule-interfering agents such as CEUs remains the major mechanism of their anticancer activity, leading to apoptosis. However, we recently demonstrated that microtubule disruption by CEUs and other common antimicrotubule agents greatly alters the integrity and organization of microtubule-associated structures, the focal adhesion contact, thereby initiating anoikis, an apoptosis-like cell death mechanism caused by the loss of cell contact with the extracellular matrix. Methods: To ascertain the activated signaling pathway profile of CEUs, flow cytometry, Western blot, immunohistochemistry and transfection experiments were performed. Wound-healing and chick embryo assays were carried out to evaluate the antiangiogenic potency of CEUs. Results: CEU-induced apoptosis involved early cell cycle arrest in G2/M and increased level of CDK1/cycline B proteins. These signaling events were followed by the specific activation of the intrinsic apoptosis pathway, involving loss of mitochondrial membrane potential (Δψm) and ROS production, cytochrome c release from mitochondria, caspase activation, AIF nuclear translocation, PARP cleavage and nuclear fragmentation. CEUs maintained their efficacy on cells plated on pro-survival extracellular matrices or exhibiting overexpression of P-glycoprotein or the anti-apoptotic protein Bcl-2. Conclusion: Our results suggest that CEUs represent a promising new class of antimicrotubule, antiangiogenic and pro-anoikis agents

Rotational Studies of Late-Type Stars. VII. M34 (NGC 1039) and the Evolution of Angular Momentum and Activity in Young Solar-Type Stars

We analyze Keck Hires observations of rotation in F, G, and K dwarf members of the open cluster M34 (NGC 1039), which is 250 Myr old, and we compare them to the Pleiades, Hyades, and NGC 6475. The upper bound to rotation seen in M34 is about a factor of two lower than for the 100 Myr-old Pleiades, but most M34 stars are well below this upper bound, and it is the overall convergence in rotation rates that is most striking. A few K dwarfs in M34 are still rapid rotators, suggesting that they have undergone core-envelope decoupling, followed by replenishment of surface angular momentum from an internal reservoir. Our comparison of rotation in these clusters indicates that the time scale for the coupling of the envelope to the core must be close to 100 Myr if decoupling does, in fact, occur.Comment: 16 pages + 1 table + 5 figure

Keck Spectra of Pleiades Brown Dwarf Candidates and a Precise Determination of the Lithium Depletion Edge in the Pleiades

We have obtained intermediate resolution spectra of eleven candidate brown dwarf members of the Pleiades open cluster using the Keck II telescope and LRIS spectrograph. Our primary goal was to determine the location of the "lithium depletion edge" in the Pleiades and hence to derive a precise age for the cluster. All but one of our 11 program objects have radial velocities appropriate for Pleiades members, have moderately strong H alpha emission, and have spectral types M6 to M8.5, as expected for their (R-I) colors. We have constructed a color-magnitude diagram for the faint end of the Pleiades main sequence, including only stars for which high S/N spectra in the region of the lithium 6708 Angstrom absorption line have been obtained. These data allow us to accurately determine the Pleiades single-star lithium depletion edge at I(c0) = 17.80, R-I(c0) = 2.20, spectral type = M6.5. By reference to theoretical evolutionary models, this converts fairly directly into an age for the Pleiades of 125 Myr. This is significantly older than the age that is normally quoted, but does agree with some other recent estimates.Comment: 12 pages, including 3 Figures. Accepted by ApJ Letter

Understanding the relationships between ecosystem services and poverty alleviation:A conceptual framework

AbstractAs interest grows in the contribution of ecosystem services to poverty alleviation, we present a new conceptual framework, synthesizing insights from existing frameworks in social–ecological systems science and international development. People have differentiated abilities to benefit from ecosystem services, and the framework places emphasis on access to services, which may constrain the poorest more than aggregate availability. Distinctions are also made between categories of ecosystem service in their contribution to wellbeing, provisioning services and cash being comparatively easy to control. The framework gives analytical space for understanding the contribution of payments for ecosystem services to wellbeing, as distinct from direct ecosystem services. It also highlights the consumption of ecosystem services by external actors, through land appropriation or agricultural commodities. Important conceptual distinctions are made between poverty reduction and prevention, and between human response options of adaptation and mitigation in response to environmental change. The framework has applications as a thinking tool, laying out important relationships such that an analyst could identify and understand these in a particular situation. Most immediately, this has research applications, as a basis for multidisciplinary, policy-relevant research, but there are also applications to support practitioners in pursuing joint policy objectives of environmental sustainability and poverty alleviation

ПОБОЧНЫЕ ЭФФЕКТЫ СОРАФЕНИБА, СУНИТИНИБА И ТЕМСИРОЛИМУСА И ИХ ЛЕЧЕНИЕ У БОЛЬНЫХ МЕТАСТАТИЧЕСКИМ ПОЧЕЧНО-КЛЕТОЧНЫМ РАКОМ

Objective: to provide a systematic review of the adverse reactions of sorafenib, sunitinib, and temsirolimus and to outline actions for their prevention and correction.Materials and methods. To provide a description of the main methods to decrease the toxicity of these drugs, the authors made a systemat- ic review of their adverse reactions, by using the publications available in the PubMed database, monographs on the medicines, and instruc- tions for their medical use. Results. The frequency of their adverse reactions varied from < 1 to 72%. Grades III—IV side effects are noted more rarely; their incidence is < 1 to 13% for sorafenib, < 1 to 16% for sunitinib, and 1 to 20% for temsirolimus. Sinitinib causes most grades III—IV adverse reactions and sofafenib does the least. However, close comparative studies of the safety of these kinase inhibitors are still lacking. Virtually all side effects can be effectively prevented and treated.  Conclusion. The prevention, timely recognition, and treatment of the adverse reactions of these agents are of great importance, which allows avoidance of the unneeded dosage reduction that may result in worse therapeutic efficiency.   Цель исследования — представить систематический обзор побочных эффектов сорафениба, сунитиниба и темсиролимуса, а также в общих чертах описать меры по их предупреждению и коррекции. Материалы и методы. Для того чтобы представить описание основных методов, направленных на снижение токсичности этих препаратов, нами проведен систематический обзор побочных эффектов на основе публикаций в базе данных PubMed, монографий по лекарственным препаратам и инструкций по их медицинскому применению.Результаты. Частота развития побочных эффектов варьирует от < 1 до 72%. Побочные эффекты III—IV степени отмечаются реже, частота их возникновения от < 1 до 13% для сорафениба, от < 1 до 16% — для сунитиниба и от 1 до 20% — для темсиролимуса. Сунитиниб вызывает наибольшее количество побочных эффектов III—IV степени, а сорафениб — наименьшее. Однако все еще отсутствуют тщательные сравнительные клинические исследования безопасности этих ингибиторов киназ. Практически все побочные эффекты можно эффективно предупреждать и лечить.Заключение. Большое значение имеют профилактика, своевременное распознавание и лечение побочных эффектов этих препаратов, что позволяет избежать ненужного снижения дозы, грозящего ослаблением эффективности лечения.

Targeting deforestation rates in climate change policy: a "Preservation Pathway" approach

We present a new methodological approach to incorporating deforestation within the international climate change negotiating regime. The approach, called "Preservation Pathway" combines the desire for forest preservation with the need to reduce emissions associated with forest loss by focusing on the relative rate of change of forest cover as the criteria by which countries gain access to trading preserved forest carbon stocks. This approach avoids the technically challenging task of quantifying historical or future deforestation emission baselines. Rather, it places emphasis on improving quantification of contemporary stocks and the relative decline in deforestation rates necessary to preserve those stocks. This approach places emphasis on the complete emissions trajectory necessary to attain an agreed-upon preserved forest and as such, meets both forest conservation and climate goals simultaneously