Seagrass meadows provide 3D habitat for reef fish

For large fishes, seagrass canopies typically provide a relatively flat habitat on seabeds, but seagrasses in the genus Posidonia can provide additional habitat complexity by forming organic-rich deposits known as mats. Erosional processes can scour channels through the mats, resulting in the formation of escarpments with caves. Here we report that reef fishes, such as groupers, inhabit the caves found within mat escarpments. The characteristics of the cavities are highly variable, ranging from small-elongated holes to deep caves with large entrances. The origin of these caves (biological and/or geological) is unknown, but it is possible that fish behavior enhance their formation. Posidonia seagrass escarpments provide a complex 3D habitat for reef fish that is not provided by typical canopy structure of seagrass. Further studies are required to gain insights into the natural history of seagrass escarpments and their ecological importance

Employment Expectations and Gross Flows by Type of Work Contract

There is growing interest in understanding firms’ temporary and permanent employment practices and how institutional changes shape them. Using data on Spanish establishments, we examine: (a) how employers adjust temporary and permanent job and worker flows to prior employment expectations, and (b) how the 1994 and 1997 labour reforms promoting permanent employment affected establishments’ employment practices. Generally, establishments’ prior employment expectations are realized through changes in all job and worker flows. However, establishments uniquely rely on temporary hires as a buffer to confront diminishing long-run employment expectations. None of the reforms significantly affected establishments’ net temporary or permanent employment flows.http://deepblue.lib.umich.edu/bitstream/2027.42/40032/3/wp646.pd

Challenges to select suitable habitats and demonstrate ‘additionality’ in Blue Carbon projects: A seagrass case study

© 2020 Elsevier Ltd Seagrass restoration has been suggested as a Blue Carbon (BC) strategy for climate change mitigation. For Nationally Determined Contributions (NDC) and carbon crediting schemes, BC projects need to demonstrate ‘additionality’, that is enhanced CO2 sequestration and/or avoided greenhouse gas emissions following management actions. This typically requires determining soil carbon accumulation rates (CAR), which is often done using radionuclides or surface elevation tables to estimate sedimentation rates. Here we undertook a case study, using 210Pb and 14C dating, to detect possible changes in Corg stocks and CAR following the loss and partial recovery of Posidonia seagrass meadows in South Australia since 1980–90s. The 210Pb data revealed a lack of accumulation of excess 210Pb in most sites, suggesting negligible accumulation of sediments, intense mixing of the upper layers, or accumulation of reworked sediments, precluding the estimation of reliable CAR at decadal time scales. This limitation was also encountered with 14C. The inability to compare sites over analogous periods of time prevented quantifying differences in soil Corg sequestration, thereby to demonstrate additionality. The lack of significant differences in soil Corg stocks among sites which never suffered seagrass loss, those showing recovery and those with no recovery (5.7 ± 1.2, 4.5 ± 0.7 and 3.3 ± 0.3 kg Corg m-2 within the top meter, respectively) also precluded estimates of soil Corg gains or losses. Our findings demonstrate that, while 210Pb and 14C provide important information on sediment deposition dynamics, it is not straightforward to demonstrate additionality using radionuclides in low depositional seagrass habitats exposed to hydrodynamic energy, features which may be encountered in seagrass sites. We provide insights for the selection of suitable habitats for seagrass BC projects, suggest possible alternative methods for estimating additionality, and discuss the implications of the findings for the implementation of seagrass BC strategies to mitigate greenhouse gas emissions

Challenges to select suitable habitats and demonstrate ‘additionality’ in Blue Carbon projects: A seagrass case study

© 2020 Elsevier Ltd Seagrass restoration has been suggested as a Blue Carbon (BC) strategy for climate change mitigation. For Nationally Determined Contributions (NDC) and carbon crediting schemes, BC projects need to demonstrate ‘additionality’, that is enhanced CO2 sequestration and/or avoided greenhouse gas emissions following management actions. This typically requires determining soil carbon accumulation rates (CAR), which is often done using radionuclides or surface elevation tables to estimate sedimentation rates. Here we undertook a case study, using 210Pb and 14C dating, to detect possible changes in Corg stocks and CAR following the loss and partial recovery of Posidonia seagrass meadows in South Australia since 1980–90s. The 210Pb data revealed a lack of accumulation of excess 210Pb in most sites, suggesting negligible accumulation of sediments, intense mixing of the upper layers, or accumulation of reworked sediments, precluding the estimation of reliable CAR at decadal time scales. This limitation was also encountered with 14C. The inability to compare sites over analogous periods of time prevented quantifying differences in soil Corg sequestration, thereby to demonstrate additionality. The lack of significant differences in soil Corg stocks among sites which never suffered seagrass loss, those showing recovery and those with no recovery (5.7 ± 1.2, 4.5 ± 0.7 and 3.3 ± 0.3 kg Corg m-2 within the top meter, respectively) also precluded estimates of soil Corg gains or losses. Our findings demonstrate that, while 210Pb and 14C provide important information on sediment deposition dynamics, it is not straightforward to demonstrate additionality using radionuclides in low depositional seagrass habitats exposed to hydrodynamic energy, features which may be encountered in seagrass sites. We provide insights for the selection of suitable habitats for seagrass BC projects, suggest possible alternative methods for estimating additionality, and discuss the implications of the findings for the implementation of seagrass BC strategies to mitigate greenhouse gas emissions

Theoretical and experimental study of mechanical losses in automotive turbochargers

The aim of the present work is to show an approximation, through an experimental an theoretical study, to quantify the mechanical losses in a turbocharging system. These are linked to the dynamics in the turbo shaft bearings, both axial and radial. Theoretical and experimental methodologies are presented in order to develop a mechanical losses model. The experimental work consists on a measurement campaign in quasi-adiabatic operating conditions, while in the theoretical part, a mathematical model is developed taking into account the radial and axial bearings. The model uses some assumptions in order to solve the Navier-Stokes equations, leading to a simplified model which includes viscosity and the Reynolds number of the oil film formed on the bearings. The proposed model has shown a good agreement with the experimental dataThe authors of this paper wish to thank M.A. Ortiz and V. Ucedo for their invaluable work during the experimental setup and campaign, F.J. Arnau, Ph.D, for its excellent job maintaining and expanding Open WAMs code base and M.A. Reyes-Belmonte for all his hard and rigorous work extrapolating turbine maps and preparing and launching the simulations. This work has been partially supported by the Spanish Ministerio de Ciencia e Innovacion through grant number DPI2010-20891-C02-02.Serrano Cruz, JR.; Olmeda González, PC.; Tiseira Izaguirre, AO.; García-Cuevas González, LM.; Lefebvre, A. (2013). Theoretical and experimental study of mechanical losses in automotive turbochargers. Energy. 55:888-898. https://doi.org/10.1016/j.energy.2013.04.042S8888985

Implication of VHL, ERK5, and HIF-1alpha in clear cell renal cell carcinoma: Molecular basis

Objectives: To determine the expression status of several proteins related to VHL gene function and its relationship with common clinicopathological parameters. Material and methods: Observational, analytical, cross-sectional study with 50 patients diagnosed with clear cell renal cell carcinoma. The study analyzed VHL mutations and hypermethylation as well as protein expression of VHL, CA-IX, HIF-1alpha, VEGF, ERK1/2, and ERK5, relating them to clinical variables. A bivariate and multivariate descriptive logistical regression analysis was performed, using the presence of metastasis at diagnosis as dependent variable. Results: The study identified 13 (26%) VHL mutations related to nuclear grade (P = 0.036). VHL hypermethylation was found in 20% of cases. VHL expression was associated with the presence of mutations (P = 0.013), and the absence of expression was associated with nuclear grade and the presence of metastasis (P<0.05). HIF-1alpha was negative in only 5 cases. Vascular endothelial growth factor (VEGF) was positive in 31 of 47 cases and was associated with Fuhrman nuclear grade, presence of metastasis, and stage (P<0.05). ERK5 expression was increased in 58% of cases and associated with the presence of metastasis and more advanced stages (P<0.05). In the logistic regression analysis, the only variable remaining in the model was VEGF expression (P = 0.014). Conclusions: VEGF has prognostic value in clear cell renal cell carcinoma, and ERK5 may be a new prognostic marker in this type of tumor owing to its relationship with metastasis and more advanced stages

Crosstalk between uterine serpin (SERPINA14) and pregnancy-associated glycoproteins at the fetal-maternal interface in pregnant dairy heifers experimentally infected with Neospora caninum

Infection with Neospora caninum is the leading cause of abortion in cattle. In cows naturally infected with N caninum, plasma concentrations of pregnancy-associated glycoproteins (PAG) 1 and 2 indicate fetal-placental well-being, whereas an excess of progesterone in the second trimester of gestation has been related to high abortion rate. The immunosuppressive action of progesterone on the uterus during gestation has been attributed in part to the uterine serpins (SERPINA14). This study examines expression patterns of the genes SERPINA14, PAG, and PAG2 at the fetal-maternal interface in dairy heifers experimentally infected with N caninum during the second trimester of pregnancy, when most abortions takes place in natural conditions. Irrespective of infection, expression of SERPINAI4 was higher, and expression of PAG1 and PAG2 lower, for intercaruncular endometrium than for caruncles or cotyledons. Cotyledonary tissues showed the highest expression of both PAG genes but lowest expression of SERPINAI4. The expression of SERPINAI4 was significantly higher in intercaruncular endometrium of control dams than for infected animals, pointing to potential disruption of modulation of maternal immune function during infection. Dramatically reduced SERPINAI4 was particularly apparent in infected dams with aborted fetuses. There was also a negative association between N caninum antibody titers with SERPINAI4 and PAG expression in infected animals, further suggesting that N caninum infection downregulates the uterine immunosuppressive function of SERPINAI4.This study was supported by a grant from the Spanish MINECO (AGL2012-39830-C02-01/02) and FEDER. Ramón Mur-Novales was awarded an FPI grant by the Spanish Ministry of Science and Innovation, MICINN, BES-2013-063215. The authors thank Ana Burton for editorial assistance, the farmers who provided the experimental animals and the staff of CReSA for their help with managing the animals, and Dr. L.M. Ortega-Mora (SALUVET, Universidad Complutense, Madrid, Spain), for the Neospora isolate