Rethinking False Spring Risk

Temperate plants are at risk of being exposed to late spring freezes. These freeze events - often called false springs - are one of the strongest factors determining temperate plants species range limits and can impose high ecological and economic damage. As climate change may alter the prevalence and severity of false springs, our ability to forecast such events has become more critical, and it has led to a growing body of research. Many false spring studies largely simplify the myriad complexities involved in assessing false spring risks and damage. While these studies have helped advance the field and may provide useful estimates at large scales, studies at the individual to community levels must integrate more complexity for accurate predictions of plant damage from late spring freezes. Here we review current metrics of false spring, and how, when and where plants are most at risk of freeze damage. We highlight how life stage, functional group, species differences in morphology and phenology, and regional climatic differences contribute to the damage potential of false springs. More studies aimed at understanding relationships among species tolerance and avoidance strategies, climatic regimes, and the environmental cues that underlie spring phenology would improve predictions at all biological levels. An integrated approach to assessing past and future spring freeze damage would provide novel insights into fundamental plant biology, and offer more robust predictions as climate change progresses, which is essential for mitigating the adverse ecological and economic effects of false springs

La persona desde el punto de vista transcendental: Zubiri y Polo

Tanto Zubiri como Polo son dos pensadores españoles del s. XX profundamente interesados por conocer y profundizar en la persona humana en cuanto tal. Ambos –aunque desde planteamientos diversos– coinciden en situar a la persona en el ámbito más profundo de la realidad, el orden transcendental. Zubiri la denomina “esa gran realidad” y para Polo es la perfección mayor del ser humano, el acto de ser único e irrepetible que actualiza cada naturaleza humana y el poder libre que posibilita desarrollarla en un crecimiento irrestricto.Both Zubiri and Polo are two Spanish thinkers of twentieth century deeply interested to know and deepen the human person as such. Both, although from different approaches, agree to place the person at the deepest level of reality, the transcendental order. Zubiri calls it “that great reality” and for Polo is the greatest perfection of human, the act of being unique and unrepeatable, that updates every human nature and the free power to develop it, in enabling unrestricted growth

Hepatoprotection and neuroprotection induced by low doses of IGF-II in aging rats

<p>Abstract</p> <p>Background</p> <p>GH and IGFs serum levels decline with age. Age-related changes appear to be associated to decreases in these anabolic hormones. We have previously demonstrated that IGF-I replacement therapy improves insulin resistance, lipid metabolism and reduces oxidative damage (in brain and liver) in aging rats. Using the same experimental model, the aim of this work was to study whether the exogenous administration of IGF-II, at low doses, acts analogous to IGF-I in aging rats.</p> <p>Methods</p> <p>Three experimental groups were included in this study: young healthy controls (yCO, 17 weeks old); untreated old rats (O, 103 weeks old); and aging rats treated with IGF-II (O+IGF-II, 2 μg * 100 g body weight^-1* day^-1) for 30 days. Analytical parameters were determined in serum by routine laboratory methods using an autoanalyzer (Cobas Mira; Roche Diagnostic System, Basel, Switzerland). Serum levels of hormones (testosterone, IGF-I and insulin) were assessed by RIA. Serum Total Antioxidant Status was evaluated using a colorimetric assay. Mitochondrial membrane potential was evaluated using rhodamine 123 dye (adding different substrates to determine the different states). ATP synthesis in isolated mitochondria was determined by an enzymatic method.</p> <p>Results</p> <p>Compared with young controls, untreated old rats showed a reduction of IGF-I and testosterone levels with a decrease of serum total antioxidant status (TAS). IGF-II therapy improved serum antioxidant capability without modifying testosterone and IGF-I circulating concentrations. In addition, IGF-II treatment reduced oxidative damage in brain and liver, improving antioxidant enzyme activities and mitochondrial function. IGF-II was also able to reduce cholesterol and triglycerides levels increasing free fatty acids concentrations.</p> <p>Conclusions</p> <p>We demonstrate that low doses of IGF-II induce hepatoprotective, neuroprotective and metabolic effects, improving mitochondrial function, without affecting testosterone and IGF-I levels.</p

Little effects of Insulin-like Growth Factor-I on testicular atrophy induced by hypoxia

BACKGROUND: Insulin-like Growth Factor-I (IGF-I) supplementation restores testicular atrophy associated with advanced liver cirrhosis that is a condition of IGF-I deficiency. The aim of this work was to evaluate the effect of IGF-I in rats with ischemia-induced testicular atrophy (AT) without liver disease and consequently with normal serum level of IGF-I. METHODS: Testicular atrophy was induced by epinephrine (1, 2 mg/Kg intra-scrotal injection five times per week) during 11 weeks. Then, rats with testicular atrophy (AT) were divided into two groups (n = 10 each): untreated rats (AT) receiving saline sc, and AT+IGF, which were treated with IGF-I (2 μg.100 g b.w.(-1).day(-1), sc.) for 28d. Healthy controls (CO, n = 10) were studied in parallel. Animals were sacrificed on day 29(th). Hypophyso-gonadal axis, IGF-I and IGFBPs levels, testicular morphometry and histopathology, immuno-histochemical studies and antioxidant enzyme activity phospholipid hydroperoxide glutathione peroxidase (PHGPx) were assessed. RESULTS: Compared to controls, AT rats displayed a reduction in testicular size and weight, with histological testicular atrophy, decreased cellular proliferation and transferrin expression, and all of these alterations were slightly improved by IGF-I at low doses. IGF-I therapy increased signifincantly steroidogenesis and PHGPx activity (p < 0.05). Interestingly, plasma IGF-I did not augment in rats with testicular atrophy treated with IGF-I, while IGFBP3 levels, that reduces IGF-I availability, was increased in this group (p < 0.05). CONCLUSION: In testicular atrophy by hypoxia, condition without IGF-I deficiency, IGF-treatment induces only partial effects. These findings suggest that IGF-I therapy appears as an appropriate treatment in hypogonadism only when this is associated to conditions of IGF-I deficiency (such as Laron Syndrom or liver cirrhosis)

Numerical simulations of thixotropic semi-solid aluminium alloys in open-rotor and rotor-stator mixers

This research uses the Bautista-Manero-Puig (BMP) model to examine flow patterns of semi-solid aluminium alloys (Al) in open-rotor and stator-rotor mixers via numerical solutions. The model captures the distinct thixo-viscoelastic behavior of the Al-alloys at low temperatures, near melting point. The analysis involves using 2D structured-meshes for open-rotor and rotor-stator geometries. Solutions for Newtonian and thixo-viscoelastic model fluids are reported through fields of velocity, strain-rate, stress, fluidity, and streamlines, revealing distinct features. Findings reveal nonlinear thixo-viscoelastic vortex patterns that vary with rotational speed, resulting in different fluidity and stress profiles compared to the invariant response of Newtonian fluids. At lower rotational speeds, rotor-pallets are dominated by structured material that gradually becomes unstructured to cover the outer vessel walls. When including a stator, the inner stator region resembles the Newtonian solution, but the outflow through stator gaps is reduced due to flow-structure levels outside. This information is of interest for industrial design and optimization of molten Al-alloy processing.Programa de Transferencia de Tecnología de la DFB FEDER Consejo Nacional de Ciencias, Humanidades y Tecnologı́as (CONAHCYT, Mexico) Universidad Nacional Autónoma de México UNA

DEVELOPMENT AND EVALUATION OF THE ATOS SPONTANEOUS SPEECH CONVERSATIONAL SYSTEM

ABSTRACT In this paper we report our recent development work in Spanish spontaneous speech conversational systems. We describe the Automatic Telephone Operator Service (ATOS) and present the improvements introduced into it to deal with spontaneous speech, which are: (a) a task independent dialogue manager, that can be adapted to a new semantic domain by changing a configuration file. It also generates a prediction about the user&apos;s expected utterance to constrain the language model used by the speech recognizer. (b) a language modeling strategy, which allows to adapt the statistical language model to a new task with just few hundreds of sentences. This strategy reduces a 27% the word error rate. We also report the results, conclusions and the speech database collected in the evaluation of the ATOS system, which has been tested by 30 real users

Spatially explicit estimates of N2O emissions from croplands suggest climate mitigation opportunities from improved fertilizer management

With increasing nitrogen (N) application to croplands required to support growing food demand, mitigating N2O emissions from agricultural soils is a global challenge. National greenhouse gas emissions accounting typically estimates N2O emissions at the country scale by aggregating all crops, under the assumption that N2O emissions are linearly related to N application. However, field studies and meta-analyses indicate a nonlinear relationship, in which N2O emissions are relatively greater at higher N application rates. Here we apply a super-linear emissions response model to crop-specific, spatially-explicit synthetic N fertilizer and manure N inputs to provide subnational accounting of global N2O emissions from croplands. We estimate 0.66 Tg of N2O-N direct global emissions circa 2000, with 50% of emissions concentrated in 13% of harvested area. Compared to estimates from the IPCC Tier 1 linear model, our updated N2O emissions range from 20-40% lower throughout Sub-Saharan Africa and Eastern Europe, to >120% greater in some Western European countries. At low N application rates, the weak non-linear response of N2O emissions suggests that relatively large increases in N fertilizer application would generate relatively small increases in N2O emissions. Since aggregated fertilizer data generate underestimation bias in nonlinear models, high-resolution N application data are critical to support accurate N2O emissions estimates

Этно-педагогические аспекты формирования интереса у девочек к физической культуре

The evolution of learning can be constrained by trade-offs. As male and female life-histories often diverge, the relationship between learning and fitness may differ between the sexes. However, because sexes share much of their genome, intersexual genetic correlations can prevent males and females from reaching their sex-specific optima resulting in intralocus sexual conflict (IaSC). To investigate if IaSC constraints sex-specific evolution of learning we selected Caenorhabditis remanei nematode females for increased or decreased olfactory learning performance and measured learning, lifespan (in mated and virgin worms), reproduction and locomotory activity in both sexes. Males from downward-selected female lines had higher locomotory activity and longer virgin lifespan but sired fewer progeny than males from upward-selected female lines. In contrast, we found no effect of selection on female reproduction and downward-selected females showed higher locomotory activity but lived shorter as virgins than upward-selected females. Strikingly, selection on learning performance led to the reversal of sexual dimorphism in virgin lifespan. We thus show sex-specific trade-offs between learning, reproduction and lifespan. Our results support the hypothesis that selection on learning performance can shape the evolution of sexually dimorphic life-histories via sex-specific genetic correlations

Human influence on growing-period frosts like the early April 2021 in Central France

International audienceAbstract. In early April 2021 several days of harsh frost affected central Europe. This led to very severe damage in grapevine and fruit trees in France, in regions where young leaves had already unfolded due to unusually warm temperatures in the preceding month (March 2021). We analysed with observations and 172 climate model simulations how human-induced climate change affected this event over central France, where many vineyards are located. We found that, without human-caused climate change, such temperatures in April or later in spring would have been even lower by 1.2 ∘C (0.75 to 1.7 ∘C). However, climate change also caused an earlier occurrence of bud burst that we characterized in this study by a growing degree day index value. This shift leaves young leaves exposed to more winter-like conditions with lower minimum temperatures and longer nights, an effect that overcompensates the warming effect. Extreme cold temperatures occurring after the start of the growing season such as those of April 2021 are now 2 ∘C colder (0.5 to 3.3 ∘C) than in preindustrial conditions, according to observations. This observed intensification of growing-period frosts is attributable, at least in part, to human-caused climate change with each of the five climate model ensembles used here simulating a cooling of growing-period annual temperature minima of 0.41 ∘C (0.22 to 0.60 ∘C) since preindustrial conditions. The 2021 growing-period frost event has become 50 % more likely (10 %–110 %). Models accurately simulate the observed warming in extreme lowest spring temperatures but underestimate the observed trends in growing-period frost intensities, a fact that yet remains to be explained. Model ensembles all simulate a further intensification of yearly minimum temperatures occurring in the growing period for future decades and a significant probability increase for such events of about 30 % (20 %–40 %) in a climate with global warming of 2 ∘C

Altered liver gene expression in CCl4-cirrhotic rats is partially normalized by insulin-like growth factor-I

We have previously shown that the administration of low doses of insulin-like growth factor-I (IGF-I) to CCl4-cirrhotic rats improves liver function and reduces fibrosis. To better understand the mechanisms behind the hepatoprotective effects of IGF-I, and to identify those genes whose expression is affected in cirrhosis and after IGF-1 treatment, we have performed differential display of mRNA analysis by means of polymerase chain reaction (PCR) in livers from control and CCl4-cirrhotic rats treated or not with IGF-I. We have identified 16 genes that were up- or down-regulated in the cirrhotic liver. IGF-I treatment partially normalized the expression of eight of these genes, including serine proteinase inhibitors such as serpin-2 and alpha-1-antichymotripsin, alpha-1-acid glycoprotein, and alpha-2u-globulin. Additionally, we show that IGF-I enhanced the regenerative activity in the cirrhotic liver, as determined by the increased expression of the proliferating cell nuclear antigen (PCNA). Finally, IGF-I treatment partially restored the expression of growth hormone receptor (GHR) and the levels of global genomic DNA methylation, which are reduced in human and experimental cirrhosis. Taken together, our observations confirm the hepatoprotective effects of IGF-I, and suggest that this action can be exerted in part through the normalization of liver gene expression, growth hormone (GH) responsiveness and global genomic DNA methylation