Moving Away from Prescriptive Pachyderm Palliatives: Toward an Integrated Assessment of Farmer-Elephant Conflict in Gabon.

Crop‐raiding by elephants poses a large threat to farmers in central Africa, where agricultural self‐sufficiency is already low. Despite overwhelming consensus on the need to reduce crop‐raiding and decades of research invested, efforts have had little success. Such efforts typically involve prescriptive low‐tech protection methods at the level of the individual farm, assuming that rational farmers will adopt such methods once provided required knowledge and skills. However, the implicit assumption, that low‐tech methods are low‐cost, generally only holds if labor costs are not considered. Labor, especially that of young males, is a limiting factor in Gabonese agriculture. In the fifty years since independence, Gabon’s population has rapidly urbanized, from 14% of the population found in urban centers in 1960, to around 80% in 2003. Emigration to urban centers, primarily for schools and jobs, has left villages increasingly devoid of youth and young adults. The farming residents, at the average age of 52, are thus left with scarce labor resources, bringing to the forefront the issue of labor in farmers’ decision‐making. I develop a theoretical model to account for labor costs in addition to monetary costs when assessing costs and benefits of farm‐level protection. I test this model empirically with data from observations and interviews with 426 farmers in 36 villages in Gabon. Findings support the hypothesis that Gabonese farmers generally receive a higher net benefit from coping strategies, such as planting extra to compensate losses, than from known protection strategies. Because known protection strategies in Gabon are generally known to be relatively inefficient at keeping elephants out of farms, I then explore how efficient such strategies would need to be to be adoptable by farmers, and how much farmers are willing to pay, in terms of different kinds of costs, for efficient strategies. I find that farm‐level protection is unlikely to be a fruitful strategy for mitigating farmer‐elephant conflict under the conditions of current agricultural and social systems in Gabon. I conclude with recommendations for an Integrated Assessment to explore alternative strategies and to begin to develop the adaptive institutions and relationships necessary to implement lasting solutions.Ph.D.Natural Resources and EnvironmentUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/75922/1/klwalker_1.pd

Landscape context importance for predicting forest transition success in central Panama

Context Naturally recovering secondary forests are frequently re-cleared before they can recover to predisturbance conditions. Identifying landscape factors associated with persistence success will help planning cost-efcient and efective forest restoration. Objectives The ability of secondary forest to persist is an often undervalued requisite for long-term ecosystem restoration. Here we identify the landscape context for naturally regenerated forests to persist through time within central Panama. Methods We developed a random forest classifcation (RFC) calibration method to identify areas with high (≥90%) and low (<90%) likelihood of forest persistence success based on their spatial relation with nine landscape explanatory variables. Results The RFC model discriminated between secondary forests areas that persisted and did not persisted with an error rate of 2%. By tuning, we obtained a precision of 0.94 (94%) in the validation test. The two most important explanatory variables involved in the persistence dynamic were elevation and distance to the nearest rural area. Naturally regenerated forests lasted longer in patches that were closer to both Gatun and Alajuela Lakes as to protected areas, but further from rural communities, roads, urban areas and in patches with higher elevation and steeper slopes. Conclusion By tracking remote sensed, landscape context metrics of easy collection, we developed a prediction map of central Panama areas with high (≥90%) and low (>90%) probability of natural forest regeneration and persistence success within the next 30 years. This map represents a basis for management decisions and future investigations for effective, longterm forest-landscape restoration

Hydrography, nutrients, and carbon pools in the Pacific sector of the Southern Ocean: Implications for carbon flux

PDF Tools Share Abstract We investigated the hydrography, nutrients, and dissolved and particulate carbon pools in the western Pacific sector of the Antarctic Circumpolar Current (ACC) during austral summer 1996 to assess the region\u27s role in the carbon cycle. Low f CO2 values along two transects indicated that much of the study area was a sink for atmospheric CO2. The f CO2 values were lowest near the Polar Front (PF) and the Subtropical Front (STF), concomitant with maxima of chlorophyll a and particulate and dissolved organic carbon. The largest biomass accumulations did not occur at fronts, which had high surface geostrophic velocities (20–51 cm s−1), but in relatively low velocity regions near fronts or in an eddy. Thus vertical motion and horizontal advection associated with fronts may have replenished nutrients in surface waters but also dispersed phytoplankton. Although surface waters north of the PF have been characterized as a “high nutrient‐low chlorophyll” region, low silicic acid (Si) concentrations (2–4 μM ) may limit production of large diatoms and therefore the potential carbon flux. Low concentrations (4–10 μM Si) at depths of winter mixing constrain the level of Si replenishment to surface waters. It has been suggested that an increase in aeolian iron north of the PF may increase primary productivity and carbon export. Our results, however, indicate that while diatom growth and carbon export may be enhanced, the extent ultimately would be limited by the vertical supply of Si. South of the PF, the primary mechanism by which carbon is exported to deep water appears to be through diatom flux. We suggest that north of the PF, particulate and dissolved carbon may be exported primarily to intermediate depths through subduction and diapycnal mixing associated with Subantarctic Mode Water and Antarctic Intermediate Water formation. These physical‐biological interactions and Si dynamics should be included in future biogeochemical models to provide a more accurate prediction of carbon flux

2015-2016 Master Class - Nancy Ambrose King (Oboe)

https://spiral.lynn.edu/conservatory_masterclasses/1012/thumbnail.jp

The Grizzly, March 19, 2015

Tops in the East: Gymnastics Will Head to NCGA Nationals • New Wins Power Games • Ursinus to Host ISGP Conference • Going Global Launches • Schellhase Contest in Progress • Simple Servings Fits Students\u27 Needs • Photo Series on Equality Sparks Discussion on Race • Hamlet Comes to Stage with Puppets • Opinion: Ditch the SAT Once and For All; Being Biracial Does not Mean Choosing Sides • Golf Teams Tee Off in 2015https://digitalcommons.ursinus.edu/grizzlynews/1927/thumbnail.jp

Paclitaxel with or without trametinib or pazopanib in advanced wild-type BRAF Melanoma (PACMEL): a multicentre, open-label, randomised, controlled phase II trial

Backround: Advanced melanoma treatments often rely on immunotherapy or targeting mutations, with few treatment options for wild-type BRAF (BRAF-wt) melanoma. However, the MAPK pathway is activated in most melanoma, including BRAF-wt. We assessed whether inhibiting this pathway by adding kinase inhibitors trametinib or pazopanib to paclitaxel chemotherapy improved outcomes in patients with advanced BRAF-wt melanoma in a phase II, randomised, open-label trial. Patients and Methods: Patients were randomised (1:1:1) to paclitaxel alone or with trametinib or pazopanib. Paclitaxel was given for a maximum of 6 cycles, while 2 mg trametinib and 800 mg pazopanib were administered orally once daily until disease progression or unacceptable toxicity. Participants and investigators were unblinded. The primary endpoint was progression-free survival (PFS). Key secondary endpoints included overall survival (OS) and objective response rate (ORR). Results: Participants were randomised to paclitaxel alone (n = 38), paclitaxel and trametinib (n = 36), or paclitaxel and pazopanib (n = 37). Adding trametinib significantly improved 6-month PFS; (time ratio (TR), 1.47; 90% confidence interval (CI): 1.08 to 2.01, P = 0.04) and ORR (42% versus 13%; P = 0.01), but had no effect on OS (P = 0.25). Adding pazopanib did not benefit 6-month PFS; (TR, 1.36; 90% CI: 0.96 to 1.93, P = 0.14), ORR, or OS. Toxicity increased in both combination arms. Conclusion: In this phase II trial, adding trametinib to paclitaxel chemotherapy for BRAF-wt melanoma improved PFS and substantially increased ORR but did not impact OS. This study was registered with the EU Clinical Trials Register, number EudraCT 2011-002545-35, and with the ISRCTN registry, number 43327231

How Low Can You Go?: Widespread Challenges in Measuring Low Stream Discharge and a Path Forward

Low flows pose unique challenges for accurately quantifying streamflow. Current field methods are not optimized to measure these conditions, which in turn, limits research and management. In this essay, we argue that the lack of methods for measuring low streamflow is a fundamental challenge that must be addressed to ensure sustainable water management now and into the future, particularly as climate change shifts more streams to increasingly frequent low flows. We demonstrate the pervasive challenge of measuring low flows, present a decision support tool (DST) for navigating best practices in measuring low flows, and highlight important method developmental needs

LGR5 receptor promotes cell-cell adhesion in stem cells and colon cancer cells via the IQGAP1 -Rac1 pathway

Leucine-rich repeat-containing G protein–coupled receptor 5 (LGR5) is a bona fide marker of adult stem cells in several epithelial tissues, most notably in the intestinal crypts, and is highly up-regulated in many colorectal, hepatocellular, and ovarian cancers. LGR5 activation by R-spondin (RSPO) ligands potentiates Wnt/β-catenin signaling in vitro; however, deletion of LGR5 in stem cells has little or no effect on Wnt/β-catenin signaling or cell proliferation in vivo. Remarkably, modulation of LGR5 expression has a major impact on the actin cytoskeletal structure and cell adhesion in the absence of RSPO stimulation, but the molecular mechanism is unclear. Here, we show that LGR5 interacts with IQ motif-containing GTPase-activating protein 1 (IQGAP1), an effector of Rac1/CDC42 GTPases, in the regulation of actin cytoskeleton dynamics and cell–cell adhesion. Specifically, LGR5 decreased levels of IQGAP1 phosphorylation at Ser-1441/1443, leading to increased binding of Rac1 to IQGAP1 and thus higher levels of cortical F-actin and enhanced cell–cell adhesion. LGR5 ablation in colon cancer cells and crypt stem cells resulted in loss of cortical F-actin, reduced cell–cell adhesion, and disrupted localization of adhesion-associated proteins. No evidence of LGR5 coupling to any of the four major subtypes of heterotrimeric G proteins was found. These findings suggest that LGR5 primarily functions via the IQGAP1–Rac1 pathway to strengthen cell–cell adhesion in normal adult crypt stem cells and colon cancer cells

A high-quality bonobo genome refines the analysis of hominid evolution

The divergence of chimpanzee and bonobo provides one of the few examples of recent hominid speciation1,2. Here we describe a fully annotated, high-quality bonobo genome assembly, which was constructed without guidance from reference genomes by applying a multiplatform genomics approach. We generate a bonobo genome assembly in which more than 98% of genes are completely annotated and 99% of the gaps are closed, including the resolution of about half of the segmental duplications and almost all of the full-length mobile elements. We compare the bonobo genome to those of other great apes1,3,4,5 and identify more than 5,569 fixed structural variants that specifically distinguish the bonobo and chimpanzee lineages. We focus on genes that have been lost, changed in structure or expanded in the last few million years of bonobo evolution. We produce a high-resolution map of incomplete lineage sorting and estimate that around 5.1% of the human genome is genetically closer to chimpanzee or bonobo and that more than 36.5% of the genome shows incomplete lineage sorting if we consider a deeper phylogeny including gorilla and orangutan. We also show that 26% of the segments of incomplete lineage sorting between human and chimpanzee or human and bonobo are non-randomly distributed and that genes within these clustered segments show significant excess of amino acid replacement compared to the rest of the genome

Non-Redfield carbon and nitrogen cycling in the Arctic: Effects of ecosystem structure and dynamics

The C:N ratio is a critical parameter used in both global ocean carbon models and field studies to understand carbon and nutrient cycling as well as to estimate exported carbon from the euphotic zone. The so-called Redfield ratio (C:N = 6.6 by atoms) [Redfield et al., 1963] is widely used for such calculations. Here we present data from the NE Greenland continental shelf that show that most of the C:N ratios for particulate (autotrophic and heterotrophic) and dissolved pools and rates of transformation among them exceed Redfield proportions from June to August, owing to species composition, size, and biological interactions. The ecosystem components that likely comprised sinking particles and had relatively high C:N ratios (geometric means) included (1) the particulate organic matter (C:N = 8.9) dominated by nutrient-deficient diatoms, resulting from low initial nitrate concentrations (approximately 4 μM) in Arctic surface waters; (2) the dominant zooplankton, herbivorous copepods (C:N = 9.6), having lipid storage typical of Arctic copepods; and (3) copepod fecal pellets (C:N = 33.2). Relatively high dissolved organic carbon concentrations (median 105 μM) were approximately 25 to 45 μM higher than reported for other systems and may be broadly characteristic of Arctic waters. A carbon-rich dissolved organic carbon pool also was generated during summer. Since the magnitude of carbon and nitrogen uncoupling in the surface mixed layer appeared to be greater than in other regions and occurred throughout the productive season, the C:N ratio of particulate organic matter may be a better conversion factor than the Redfield ratio to estimate carbon export for broad application in northern high-latitude systems