Learning resilience: Household and institutional responses to multiple livelihood threats in the context of Hurricanes Iota and Eta in northern Nicaragua

Despite converging agendas identifying the importance of farm and livelihood diversification as a key strategy to help reduce disaster risk, conserve biodiversity, reduce climate emissions, improve food security, and build resilience in agriculture and food systems (Kremen and Merenlender 2018; Hufnagel et al., 2020), contentious debates continue about how to accelerate broader food system transformations, who should lead them, and where they are going (e.g., the 2021 UN Food Summit). The influential 2016 report of the International Panel of Experts on Sustainable Food Systems, which analyzed obstacles and opportunities for moving from either traditional subsistence agriculture or industrialized monoculture towards diversified agroecological farming (IPES-Food 2016), helped shift the policy agenda toward an alternative approach to food systems transformation (Gliessman & Ferguson, 2020). However, several assumptions about farmers’ initial starting conditions oversimplified how smallholder farmers begin potential transitions. In practice, many smallholders are neither purely subsistence producers nor entirely specialized commodity farmers; instead they combine subsistence and commercial agriculture to try to make a living, feed themselves, shape their cultures, and achieve their self-defined goals (Burnett & Murphy, 2014). Despite recent studies addressing several of these issues (Kerr et al., 2019), research gaps remain, including the absence of broad-based empirical evidence on which diversification strategies are most likely to contribute to farmers’ dietary diversity, food sovereignty, food security, women’s empowerment, and resilience, and under what circumstances; how smallholders learn about these practices and why they adopt or avoid them; and how cooperatives or other institutions promote (or may retard) them. We seek to fill these gaps using a mixed-methods, place-based study

A Verilog-A Based Fractional Frequency Synthesizer Model for Fast and Accurate Noise Assessment

This paper presents a new strategy to simulate fractional frequency synthesizer behavioral models with better performance and reduced simulation time. The models are described in Verilog-A with accurate phase noise predictions and they are based on a time jitter to power spectral density transformation of the principal noise sources in a synthesizer. The results of a fractional frequency synthesizer simulation is compared with state of the art Verilog-A descriptions showing a reduction of nearly 20 times. In addition, experimental results of a fractional frequency synthesizer are compared to the simulation results to validate the proposed model

Stenocarpella maydis and Sporisorium reilianum: Two Pathogenic Fungi of Maize

Stenocarpella maydis and Sporisorium reilianum are phytopathogenic fungi that cause white rot in corn cob and head smut in maize (Zea mays L.) respectively, diseases that are spread worldwide and cause many economic losses. In this chapter the characteristics of the above diseases, such as their life cycle, pathogenicity factors, control methods, as well as the biotechnological potential of the fungi involved in this processes are described, specifically in connection to their extracellular enzymes

Biochemical characterization of recombinant Candida albicans mannosyltransferases Mnt1, Mnt2 and Mnt5 reveals new functions in O- and N-mannan biosynthesis

Peer reviewedPublisher PD

Ethanol-Induced Oxidative Stress Modifies Inflammation and Angiogenesis Biomarkers in Retinal Pigment Epithelial Cells (ARPE-19): Role of CYP2E1 and its Inhibition by Antioxidants

The retinal pigment epithelium (RPE) plays a key role in retinal health, being essential for the protection against reactive oxygen species (ROS). Nevertheless, excessive oxidative stress can induce RPE dysfunction, promoting visual loss. Our aim is to clarify the possible implication of CYP2E1 in ethanol (EtOH)-induced oxidative stress in RPE alterations. Despite the increase in the levels of ROS, measured by fluorescence probes, the RPE cells exposed to the lowest EtOH concentrations were able to maintain cell survival, measured by the Cell Proliferation Kit II (XTT). However, EtOH-induced oxidative stress modified inflammation and angiogenesis biomarkers, analyzed by proteome array, ELISA, qPCR and Western blot. The highest EtOH concentration used stimulated a large increase in ROS levels, upregulating the cytochrome P450-2E1 (CYP2E1) and promoting cell death. The use of antioxidants such as N-acetylcysteine (NAC) and diallyl sulfide (DAS), which is also a CYP2E1 inhibitor, reverted cell death and oxidative stress, modulating also the upstream angiogenesis and inflammation regulators. Because oxidative stress plays a central role in most frequent ocular diseases, the results herein support the proposal that CYP2E1 upregulation could aggravate retinal degeneration, especially in those patients with high baseline oxidative stress levels due to their ocular pathology and should be considered as a risk factor.LVG was recipient of a pre-doctoral fellowship (EDUCV-PRE-2015-006). Financial support by grant #94/2016 from the PROMETEO program from the Generalitat Valenciana, Valencia, Spain, to FJR

Gαq activation modulates autophagy by promoting mTORC1 signaling.

The mTORC1 node plays a major role in autophagy modulation. We report a role of the ubiquitous Gαq subunit, a known transducer of plasma membrane G protein-coupled receptors signaling, as a core modulator of mTORC1 and autophagy. Cells lacking Gαq/11 display higher basal autophagy, enhanced autophagy induction upon different types of nutrient stress along with a decreased mTORC1 activation status. They are also unable to reactivate mTORC1 and thus inactivate ongoing autophagy upon nutrient recovery. Conversely, stimulation of Gαq/11 promotes sustained mTORC1 pathway activation and reversion of autophagy promoted by serum or amino acids removal. Gαq is present in autophagic compartments and lysosomes and is part of the mTORC1 multi-molecular complex, contributing to its assembly and activation via its nutrient status-sensitive interaction with p62, which displays features of a Gαq effector. Gαq emerges as a central regulator of the autophagy machinery required to maintain cellular homeostasis upon nutrient fluctuations.We thank Paula Ramos, Susana Rojo-Berciano, and Laura López for helpful technicalassistance. Dr. Marta Cruces (Universidad Autónoma de Madrid, Spain) for herinvaluable help regarding the liver explants experiments, Dr. Badford Berk (University ofRochester, NY, USA) for providing the GFP-Flag-PB1-p62 plasmid, Drs. Stefan Offer-manns and Nina Wettschureck (Max-Planck-Institute for Heart and Lung Research,Germany) for providing Tie2-CreERT2; Gnaq f/f; Gna11−/−[EC-q/11-KO) mice, andDr. Guzmán Sánchez for scientific advice. We thank also Ricardo Ramos from theGenomic facility of Fundación Parque Científico de Madrid (Universidad Autónoma deMadrid, Spain) and Gemma Rodríguez-Tarduchy from the Genomic facility of theInstituto de Investigaciones Biomédicas“Alberto Sols”for their help with cell linesauthentication. The help from CBMSO Animal Care, Flow Cytometry, Electron andOptical and Confocal Microscopy facilities is also acknowledged. This work was sup-ported by Ministerio de Economía; Industria y Competitividad (MINECO) of Spain(grant SAF2017-84125-R to F.M.), (grant BFU2017-83379-R to A.M.A.), Instituto deSalud Carlos III (PI18/01662 to CR, co-funded with European FEDER contribution),CIBERCV-Instituto de Salud Carlos III, Spain (grant CB16/11/00278 to F.M., co-fundedwith European FEDER contribution), Fundación Ramón Areces (to C.R. and F.M.) andPrograma de Actividades en Biomedicina de la Comunidad de Madrid-B2017/BMD-3671-INFLAMUNE to F.M. and NIH grants AG021904 and AG038072 to A.M.C. Wealso acknowledge the support of a Contrato para la Formación del Profesorado Uni-versitario (FPU13/04341) and (FPU14/06670), an EMBO short-term fellowship (ASTF600-2016). We also acknowledge institutional support to the CBMSO from FundaciónRamón Areces.S

Paleoseismology of a major crustal seismogenic source near Mexico City. The southern border of the Acambay Graben

The Trans-Mexican Volcanic Belt is an active continental volcanic arc related to subduction along the Middle America trench. It is characterized by intra-arc extension resulting into several major arc-parallel active fault systems and tectonic basins. The Acambay graben, one of the largest of these basins, is located near Mexico City, in the central part of this province. In 1912, a M 6.9 earthquake ruptured the surface along the northern border of the graben together with at least two other faults. In this paper, we analyze the paleoseismic history of the southern border of the Acambay Graben, with new observations made in one natural outcrop and four paleoseismological trenches excavated across branches of the Venta de Bravo Fault at the site where it overlaps with the Pastores Fault. We present evidence of at least two paleo-earthquakes that occurred between 12,190 +/- 175 and 5,822 +/- 87 cal year BP and between 647 +/- 77 and 250 cal year BP. On one of these branches, we estimate a minimum slip-rate value between 0.1 and 0.23 mm/year for the last 12 ka and a mean recurrence interval of 8.5 +/- 3 ka. By considering several likely rupture lengths along the Venta de Bravo and Pastores faults, we calculated a maximum possible magnitude of M-w 7.01 +/- 0.27. Finally, by correlating events recorded along different faults within the Acambay Graben, we discuss several possible rupture coalescent scenarios and related consequences for Mexico City

Drainage And Sedimentary Response Of The Northern Andes And The Pebas System To Miocene Strike-slip Tectonics: A Source To Sink Study Of The Magdalena Basin

Miocene strike-slip tectonics was responsible for creating and closing short-lived (ca. 6 Ma) passages and the emergence of isolated topography in the Northern Andes. These geological events likely influenced the migration and/or isolation of biological populations. To better understand the paleogeography of the Miocene hinterland and foreland regions in the Northern Andes, we conducted a source-to-sink approach in the Magdalena Basin. This basin is located between the Central and Eastern Cordilleras of Colombia and contains an ample Miocene record, which includes Lower Miocene fine-grained strata and Middle Miocene to Pliocene coarsening-up strata. Our study presents a new data set that includes detrital U–Pb zircon ages (15 samples), sandstone petrography (45 samples) and low-temperature thermochronology from the Southern Central Cordillera (19 dates); which together with previously published data were used to construct a paleogeographical model of the Miocene hinterland and foreland regions in the Northern Andes. The evolution of the Magdalena Basin during the Miocene was characterized by playa and permanent lake systems at ca. 17.5 Ma, which may be related to a marine incursion into NW South America and western Amazonia. The appearance of Eocene to Miocene volcanic sources in the Honda Group after ca. 16 Ma suggests the development of fluvial passages, which connected the Pacific with the western Amazonia and Caribbean regions. These passages were synchronous with a time of Miocene exhumation and topographic growth (ca. 16 to 10 Ma) in the Central Cordillera and the transition from lacustrine to fluvial deposition in the Magdalena Basin. Middle to Late Miocene strike-slip deformation promoted by oblique plate convergence and the oblique collision of the Panamá-Chocó Block likely explains the synchronous along-strike fragmentation and exhumation in the Central Cordillera

Bounding Helly numbers via Betti numbers

We show that very weak topological assumptions are enough to ensure the existence of a Helly-type theorem. More precisely, we show that for any non-negative integers $b$ and $d$ there exists an integer $h(b,d)$ such that the following holds. If $\mathcal F$ is a finite family of subsets of $\mathbb R^d$ such that $\tilde\beta_i\left(\bigcap\mathcal G\right) \le b$ for any $\mathcal G \subsetneq \mathcal F$ and every $0 \le i \le \lceil d/2 \rceil-1$ then $\mathcal F$ has Helly number at most $h(b,d)$. Here $\tilde\beta_i$ denotes the reduced $\mathbb Z_2$-Betti numbers (with singular homology). These topological conditions are sharp: not controlling any of these $\lceil d/2 \rceil$ first Betti numbers allow for families with unbounded Helly number. Our proofs combine homological non-embeddability results with a Ramsey-based approach to build, given an arbitrary simplicial complex $K$, some well-behaved chain map $C_*(K) \to C_*(\mathbb R^d)$.Comment: 29 pages, 8 figure