Selectivity, pulse fishing and endogenous lifespan in Beverton-Holt models

Optimal management in a multi-cohort Beverton-Holt model with any number of age classes and imperfect selectivity is equivalent to finding the optimal fish lifespan by chosen fallow cycles. Optimal policy differs in two main ways from the optimal lifespan rule with perfect selectivity. First, weight gain is valued in terms of the whole population structure. Second, the cost of waiting is the interest rate adjusted for the increase in the pulse length. This point is especially relevant for assessing the role of selectivity. Imperfect selectivity reduces the optimal lifespan and the optimal pulse length. We illustrate our theoretical findings with a numerical example. Results obtained using global numerical methods select the optimal pulse length predicted by the optimal lifespan rule

The impact of environmental performance on stock prices in the green and innovative context

.This study examines the impact of environmental performance on firms' stock prices, considering the moderating effect of the green and innovative environmental context by country. Renewable energy policies, green technologies, and foreign trade form this environmental context of interest for the reduction of carbon emissions. Using a sample of 2638 firm-year observations for the firms listed in the main stock index of 16 European countries over the period of 2005–2017, we find that environmental performance is value-relevant, except during the worst years of a crisis, when it is not significant. Two elements of the green technological framework, namely, renewable energy policies and the potential transmission effect of technology through foreign trade, are valued by investors as offsetting factors of the positive effect exerted by carbon performance on the firm's value. This is consistent with the slow and costly adoption of greener technologies. However, registered green patents appear to be a turning point, showing a significant positive effect on the relationship between firms' environmental performances and their market values. Again, the crisis period interferes with deepening the negative effect of renewable energy policies and cancelling out the effect of green patents and foreign trade. On one hand, our results highlight the market's role in making inefficiencies visible and showing the potential future losses of green and innovative policies; on the other hand, the hampering interference of crisis periods must be considered by policymakers.S

Production of new unsaturated lipids during wood decay by ligninolytic basidiomycetes

Instituto de Recursos Naturales y Agrobiología, Consejo Superior de Investigaciones Científicas, E-41080, Seville,1 and Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, E-28006 Madrid,2 SpainLipids were analyzed by gas chromatography-mass spectrometry for a 7-week in vitro decay of eucalypt wood by four ligninolytic basidiomycetes. The sound wood contained up to 75 mg of lipophilic compounds per 100 g of wood. Hydrolysis of sterol esters, which represented 38% of total wood lipids, occurred during the fungal decay. The initial increase of linoleic and other free unsaturated fatty acids paralleled the decrease of sterol esters. Moreover, new lipid compounds were found at advanced stages of wood decay that were identified from their mass spectra as unsaturated dicarboxylic acids consisting of a long aliphatic chain attached to the C-3 position of itaconic acid. These dicarboxylic acids were especially abundant in the wood treated with Ceriporiopsis subvermispora (up to 24 mg per 100 g of wood) but also were produced by Phlebia radiata, Pleurotus pulmonarius, and Bjerkandera adusta. We hypothesize that three main alkylitaconic acids (tetradecylitaconic, cis-7-hexadecenylitaconic, and hexadecylitaconic acids) are synthesized by fungi in condensation reactions involving palmitic, oleic, and stearic acids. We suggest that both wood unsaturated fatty acids (present in free form or released from esters during natural decay) and unsaturated metabolites synthesized by fungi could serve as a source for peroxidizable lipids in lignin degradation by white rot basidiomycetes.This study was supported by the European Commission (contract QLK5-99-1357) and the Spanish CICYT (FEDER project 1FD97-0742).Peer reviewe

Analysis of Turkish swordfish (Xiphias gladius) catch rates in the eastern Mediterranean

Indices of abundance of swordfish (Xiphias gladius) from the Turkish gillnet and longline fisheries operating in the eastern Mediterranean are presented for the period 2008-2013. Annual standardized indices were estimated by means of Generalized Linear Modeling techniques and the predictor variables included the Year and, Month of sampling. Gillnet CPUE data suggested the presence of and increasing abundance trend over the period 2008- 2010, while not any particular trend was identified from the analysis of the longline data set.Versión del edito

Tissue Localization and Extracellular Matrix Degradation by PI, PII and PIII Snake Venom Metalloproteinases: Clues on the Mechanisms of Venom-Induced Hemorrhage

20 páginas, 4 figuras, 3 tablas y 7 tablas en material suplementario.Snake venom hemorrhagic metalloproteinases (SVMPs) of the PI, PII and PIII classes were compared in terms of tissue localization and their ability to hydrolyze basement membrane components in vivo, as well as by a proteomics analysis of exudates collected in tissue injected with these enzymes. Immunohistochemical analyses of co-localization of these SVMPs with type IV collagen revealed that PII and PIII enzymes co-localized with type IV collagen in capillaries, arterioles and post-capillary venules to a higher extent than PI SVMP, which showed a more widespread distribution in the tissue. The patterns of hydrolysis by these three SVMPs of laminin, type VI collagen and nidogen in vivo greatly differ, whereas the three enzymes showed a similar pattern of degradation of type IV collagen, supporting the concept that hydrolysis of this component is critical for the destabilization of microvessel structure leading to hemorrhage. Proteomic analysis of wound exudate revealed similarities and differences between the action of the three SVMPs. Higher extent of proteolysis was observed for the PI enzyme regarding several extracellular matrix components and fibrinogen, whereas exudates from mice injected with PII and PIII SVMPs had higher amounts of some intracellular proteins. Our results provide novel clues for understanding the mechanisms by which SVMPs induce damage to the microvasculature and generate hemorrhage.This work was performed in partial fulfillment of the requirements for the PhD degree for Cristina Herrera at Universidad de Costa Rica.Peer reviewe

Characterization of EEG patterns in brain-injured subjects and controls after a Snoezelen® intervention

Producción CientíficaBackground and objective. The aim of this study was to assess the changes induced in electroencephalographic (EEG) activity by a Snoezelen® intervention on individuals with brain-injury and control subjects. Methods: EEG activity was recorded preceding and following a Snoezelen® session in 18 people with cerebral palsy (CP), 18 subjects who have sustained traumatic brain-injury (TBI) and 18 controls. EEG data were analyzed by means of spectral and nonlinear measures: median frequency (MF), individual alpha frequency (IAF), sample entropy (SampEn) and Lempel-Ziv complexity (LZC). Results: Our results showed decreased values for MF, IAF, SampEn and LZC as a consequence of the therapy. The main changes between pre-stimulation and post-stimulation conditions were found in occipital and parietal brain areas. Additionally, these changes are more widespread in controls than in brain-injured subjects, which can be due to cognitive deficits in TBI and CP groups. Conclusions: Our findings support the notion that Snoezelen® therapy affects central nervous system, inducing a slowing of oscillatory activity, as well as a decrease of EEG complexity and irregularity. These alterations seem to be related with higher levels of relaxation of the participants.Ministerio de Economía y Competitividad (TEC2014-53196-R)Junta de Castilla y León (VA059U13 y BIO/VA08/15

Chemical characterization of residual lignins from eucalypt paper pulps

aCentro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040 Madrid, Spain bInstituto de Recursos Naturales y Agrobiología, CSIC, PO Box 1042, E-41080 Sevilla, Spain cENCE, CIT, Carretera de Campañó s/n, E-36157 Pontevedra, SpainResidual lignins were isolated from eucalypt kraft pulps by enzymatic hydrolysis of cellulose followed by purification using a combination of proteinase hydrolysis and solvent extraction. The residual lignins isolated from brown (unbleached) and totally chlorine free (TCF) bleached pulps were analyzed by Fourier-transform infrared (FTIR) spectroscopy and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), and compared with eucalypt milled-wood lignin and kraft lignin. The lignin in eucalypt wood and pulps showed a strong predominance of syringyl (S) over guaiacyl (G) units. The strongest lignin modification was observed in the kraft lignin recovered from the alkaline pulping liquor. The chemical composition of the residual lignin from pulp was closer to milled-wood lignin than to the kraft lignin, indicating that most of the lignin modified during pulping was released to the cooking liquor. During TCF bleaching of pulp, which included oxygen delignification and peroxide stages, modifications of lignin were produced resulting in increased amount of non-conjugated carbonyl groups. We concluded that residual lignin in eucalypt kraft pulp reflects native lignin moieties entrapped into the cellulosic network thus partially avoiding their attack by chemical reagents, although different modifications are produced during the bleaching stages.This study has been supported by ENCE, the EU-Contract QLK5-99-1357, and the Spanish project AGL2002-00393.Peer reviewe

Virtual reality training platform for flexible ureterorenoscopy interventions with a minimally invasive surgical robot

The total number of ureteroscopy (URS) interventions during the past years has dramatically increased due to the ongoing technological advances and the benefits associated with these techniques. However, the current URS procedure presents some drawbacks to urologic surgeons. The LITHOS project was created with the main objective of developing a surgical robotic system for flexible ureterorenoscopic lithotripsy interventions, offering a technological solution that meets the real needs of both patients and surgeons in this type of procedures. In this paper, a virtual reality environment for flexible ureterorenoscopy interventions is presented. The proposed environment provides a suitable training platform for surgeons manipulating the surgical robotic system

Elucidating the Mechanism of Action of the Attributed Immunomodulatory Role of Eltrombopag in Primary Immune Thrombocytopenia: An In Silico Approach

Intel·ligència artificial; Eltrombopag; Trombocitopènia immune primàriaInteligencia artificial; Eltrombopag; Trombocitopenia inmune primariaArtificial intelligence; Eltrombopag; Primary immune thrombocytopeniaEltrombopag is a thrombopoietin receptor (MPL) agonist approved for the treatment of primary immune thrombocytopenia (ITP). Recent evidence shows that some patients may sustain platelet counts following eltrombopag discontinuation. The systemic immunomodulatory response that resolves ITP in some patients could result from an increase in platelet mass, caused either by the direct action of eltrombopag on megakaryocytes through MPL stimulation, or potential MPL-independent actions on other cell types. To uncover the possible mechanisms of action of eltrombopag, in silico analyses were performed, including a systems biology-based approach, a therapeutic performance mapping system, and structural analyses. Through manual curation of the available bibliography, 56 key proteins were identified and integrated into the ITP interactome analysis. Mathematical models (94.92% mean accuracy) were obtained to elucidate potential MPL-dependent pathways in non-megakaryocytic cell subtypes. In addition to the effects on megakaryocytes and platelet numbers, the results were consistent with MPL-mediated effects on other cells, which could involve interferon-gamma, transforming growth factor-beta, peroxisome proliferator-activated receptor-gamma, and forkhead box protein P3 pathways. Structural analyses indicated that effects on three apoptosis-related proteins (BCL2L1, BCL2, BAX) from the Bcl-2 family may be off-target effects of eltrombopag. In conclusion, this study proposes new hypotheses regarding the immunomodulatory functions of eltrombopag in patients with ITP.This research was funded and promoted by Novartis, which contributed to setting up fundamental questions relevant for the study and reviewing the manuscript. However, the company did not have a role on study design, data collection, analysis, or interpretation

Adaptation and Psychometric Properties of the Spanish Version of Child and Youth Resilience Measure (CYRM-32)

Resilience is defined as a dynamic process that entails a positive adaptation to contexts of adversity. According to the ecological model, resilient behavior emerges as a result of the interaction between individual, relational, community and cultural variables. The Child and Youth Resilience Measure (CYRM-28), developed in Canada and based on the ecological model, has been validated in several countries. The objective of this article is to present the cultural adaptation (studies I and II) and validation (study III) in Spanish at risk youth. A three-study mixed-method design was selected. Study I includes translations and a confirmatory and exploratory factor analysis of a sample of 270 Spanish young persons (56.9% boys) aged between 12 and 18 years (M = 14.65; SD = 1.27) from an urban public elementary school. Study II uses semi-structured interviews with adolescents identified as resilient and presents a content analysis and a reformulation of items with experts. Study III includes the confirmatory factor analysis, internal consistency, test-retest, convergent and discriminant validity, and multivariate analysis of variance to explore group differences of the resulting scale CYRM-32. The sample consisted of 432 at-risk young persons (54.9% boys) aged between 12 and 19 years old (M = 14.99; SD = 2.23). The results confirm the adequate psychometric properties of the CYRM-32 scale. From the original scale, 4 items were eliminated, 5 were reformulated presenting very low saturations. Meanwhile, 6 items were added to the cultural adaptation phase, resulting in a 32-item scale. The confirmatory analysis confirms the 3 factors expected in the CYRM-32 scale with good reliability indexes (Cronbach's α total scale 0.88, family interaction 0.79, interaction with others 0.72 and individual skills 0.78). The scale has convergent and discriminant validity in relation to the Brief Resilient Coping Scale, Coping Scale for Adolescents and Self-Concept. Significant differences were found in the scores of the CYRM-32 scale for the ethnic variable [F(71. 358) = 1.714, p < 0.001], while no differences appear according to age and gender. This finding confirms the importance of culture in the resiliency processes. The CYRM-32 scale has good psychometric properties and is a new alternative for measuring resilience in Spanish at-risk youth