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Cerebral palsy (CP) is characterized by motor disorders, including deficits in locomotor activity, coordination, and balance. Selective serotonin reuptake inhibitors have been shown to play an important role in brain plasticity. This study investigates the effect of neonatal treatment using fluoxetine on locomotor activity and histomorphometric parameters of the primary somatosensory cortex (S1) in rats submitted to an experimental model of CP. CP was found to reduce bodyweight and locomotion parameters and also to increase the glia/neuron index in the S1. Administration of fluoxetine 10 mg/kg reduced bodyweight, impaired locomotor activity parameters, and increased the number of glial cells and the glia/neuron ratio in the S1 in rats with CP. However, treatment with fluoxetine 5 mg/kg was not found to be associated with adverse effects on locomotor activity and seems to improve histomorphometric parameters by way of minor changes in the S1 in animals with CP. These results thus indicate that experimental CP, in combination with the use of a high dose of fluoxetine (10 mg/kg), impairs locomotor and histomorphometric parameters in the S1, while treatment with a low dose of fluoxetine (5 mg/kg) averts the negative outcomes associated with a high dose of fluoxetine in relation to these parameters but produces no protective effect. [ABSTRACT FROM AUTHOR]

Purpose: To analyze the influence of Caucasian mitochondrial haplogroups on controlled ovarian stimulation outcome (COS), embryo (E), and pregnancy success. Methods: In a Caucasian population (n = 517) undergoing COS, mitochondrial haplogroups and physiological parameters were determined. Patients were classified, according to Bologna criteria, as good (>3)/poor ≤3) responder, on dependence of recruited oocytes (RO), and in pregnancy/non-pregnancy groups. Haplogroups were determined by sequencing mitochondrial hypervariable sequence I and confirmed by polymerase chain reaction (PCR), followed by restriction fragment length polymorphisms (RFLP). Results: The rank of total dose of FSH (TD FSH) was similar in all clusters/haplogroups, except in JT, which is narrower (950–3,650 IU), particularly in T (1,350–3,650 IU). The statistical analysis showed higher RO and E in JT when compared to U, although it was only Uk which accumulated significantly in pregnancy respect to JT. Pearson's correlations between TD FSH and RO showed negative statistical significance in all population (P = 0.001), H (P = 0.03), JT (P = 0.01), and T (P = 0.03). The percentage of contribution of TD FSH on RO was almost nine times in the JT cluster as compared to all population one. Conclusions: JT cluster shows a different influence of TD FSH on RO. JT cluster shows higher RO and E than U, but it is Uk which exhibits a significant higher pregnancy rate than JT. The negative influence of the JT cluster on pregnancy success strongly suggests that the m.4216 T > C polymorphism could be responsible. [ABSTRACT FROM AUTHOR]

Purpose: To conduct a systematic review to analyse the performance of the sentinel lymph-node biopsy (SLNB) in women with node-positive breast cancer at diagnosis and node-negative tumour after neoadjuvant therapy, compared to axillary lymph-node dissection. Methods: The more relevant databases were searched. Main outcomes were false-negative rate (FNR), sentinel lymph-node identification rate (SLNIR), negative predictive value (NPV), and accuracy. We conducted meta-analyses when appropriate. Results: Twenty studies were included. The pooled FNR was 0.14 (95% CI 0.11–0.17), the pooled SLNIR was 0.89 (95% CI 0.86–0.92), NPV was 0.83 (95% CI 0.79–0.87), and summary accuracy was 0.92 (95% CI 0.90–0.94). SLNB performed better when more than one node was removed and double mapping was used. Conclusions: SLNB can be performed in women with a node-negative tumour after neoadjuvant therapy. It has a better performance when used with previous marking of the affected node and with double tracer. [ABSTRACT FROM AUTHOR]

Copyright of Revista Paranaense de Desenvolvimento is the property of Revista Paranaense de Desenvolvimento and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: We conducted a systematic review to analyse the performance of the sentinel lymph-node biopsy (SLNB) after the neoadjuvant chemotherapy, compared to axillary lymph-node dissection, in terms of false-negative rate (FNR) and sentinel lymph-node identification rate (SLNIR), sensitivity, negative predictive value (NPV), need for axillary lymph-node dissection (ALND), morbidity, preferences, and costs. Methods: MEDLINE, Embase, Scopus, and The Cochrane Library were searched. We assessed the quality of the included systematic reviews using AMSTAR2 tool, and estimated the degree of overlapping of the individual studies on the included reviews. Results: Six systematic reviews with variable quality were selected. We observed a very high overlapping degree across the included reviews. The FNR and the SLNIR were quite consistent (FNR 13–14%; SLNIR ~ 90% or higher). In women with initially clinically node-negative breast cancer, the FNR was better (6%), with similar SLNIR (96%). The included reviews did not consider the other prespecified outcomes. Conclusions: It would be reasonable to suggest performing an SLNB in patients treated with NACT, adjusting the procedure to the previous marking of the affected lymph node, using double tracer, and biopsy of at least three sentinel lymph nodes. More well-designed research is needed. PROSPERO registration number: CRD42020114403. [ABSTRACT FROM AUTHOR]

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Copyright of Cirugía y Cirujanos is the property of Publicidad Permanyer SLU and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ecologists have long debated the properties that confer stability to complex, species-rich ecological networks. Species-level soil food webs are large and structured networks of central importance to ecosystem functioning. Here, we conducted an analysis of the stability properties of an up-to-date set of theoretical soil food web models that account both for realistic levels of species richness and the most recent views on the topological structure (who is connected to whom) of these food webs. The stability of the network was best explained by two factors: strong correlations between interaction strengths and the blocked, nonrandom trophic structure of the web. These two factors could stabilize our model food webs even at the high levels of species richness that are typically found in soil, and that would make random systems very unstable. Also, the stability of our soil food webs is well-approximated by the cascade model. This result suggests that stability could emerge from the hierarchical structure of the functional organization of the web. Our study shows that under the assumption of equilibrium and small perturbations, theoretical soil food webs possess a topological structure that allows them to be complex yet more locally stable than their random counterpart. In particular, results strongly support the general hypothesis that the stability of rich and complex soil food webs is mostly driven by correlations in interaction strength and the organization of the soil food web into functional groups. The implication is that in real-world food web, any force disrupting the functional structure and distribution pattern of interaction strengths (i.e., energy fluxes) of the soil food webs will destabilize the dynamics of the system, leading to species extinction and major changes in the relative abundances of species. [ABSTRACT FROM AUTHOR]

Copyright of Cirugía y Cirujanos is the property of Publicidad Permanyer SLU and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: To determine the influence of different genotypes of Ala307Thr and Asn680Ser FSHr polymorphisms on controlled ovarian stimulation (COS) outcome and pregnancy. Methods: This study collected blood and physiological and clinical parameters of 517 Caucasian patients (Statistical power ≥ 80%) that underwent COS treatment. Genotypes of Ala307Thr and Asn680Ser polymorphisms were determined using PCR amplification followed by Bsu36I and BsrI digestion, respectively. Results: Ala307Ala and Ser680Ser genotypes associated to worse parameters of COS outcome (preovulatory follicles P = 0.05, in both), justifying their lower pregnancy rate than Non-Ala307Ala, P = 0.01 and Non-Ser680Ser, P = 0.004, respectively or together, (P = 0.003). Within the Non-Ala307Ala group, Thr307Thr genotype showed higher number of fertilized oocytes (P = 0.04) and embryos (P = 0.01) than Non-Thr307Thr, but no influence on pregnancy rate. Ala307Ala and Ser680Ser patients doubled probability of non-pregnancy than Non-Ala307Ala (odds ratio = 2.0) and Non-Ser680Ser (odds ratio = 2.11), respectively. Ala307Ala and Ser680Ser genotypes tend to appear together (P < 0.0001), which increases the probability of non-pregnancy. Conclusions: Ala307Ala and Ser680Ser genotypes of 307 and 680 FSHr polymorphisms associate to worse COS outcome than its respective Non-Ala307Ala and Non-Ser680Ser. Within the Non-Ala307Ala genotypes, Thr307Thr, although shows higher Fertilized Oocytes and Embryos, do not influence on pregnancy rate. Ala307Ala and Ser680Ser genotypes double the probability of Non-Pregnancy than their respective Non-Ala307Ala and Non-Ser680Ser genotypes. Furthermore, the strong tendency of these genotypes to appear together worsens the probability of pregnancy in these patients. [ABSTRACT FROM AUTHOR]

Summary: Brazil has one of the largest varieties of aquatic ecosystems and rich freshwater biodiversity, but these components have constantly been damaged by the expansion of unsustainable activities. Free-living nematodes are an abundant and ubiquitous component of continental benthic communities, occurring in all freshwater habitats, including extreme environments. Despite this, hardly any studies have examined the generic composition of nematodes in different latitudes and the geographic overlap of assemblages. We provide data on nematode genera from six regions in Brazil, over a north-south gradient spanning about 4000 km, encompassing rivers, coastal lakes, and reservoirs with different levels of human impact. Interpolation/extrapolation curves were generated and the zeta diversity was used to assess the overlap of nematode assemblages. Freshwater nematode assemblages comprised 54 families and 132 genera. Mononchidae, Monhysteridae, Chromadoridae, Tobrilidae and Dorylaimidae were the most diverse families. Differences in diversity and high turnover of genera were found among regions, probably related to stochastic processes. Mononchus was the only widely distributed genus. Our results revealed a high biodiversity of free-living freshwater nematodes among the regions. The limited spatial coverage of the data reveals an enormous knowledge gap in a country with 12% of the world's freshwater resources. The lack of spatial patterns, e.g. , latitudinal variation, suggests that freshwater nematode assemblages are primarily structured by the intrinsic properties of habitats. This reinforces the uniqueness of freshwater ecosystems and suggests that the nematode assemblages may be sensitive to environmental disturbances, since the limited distributions of taxa may lead to lower resilience. [ABSTRACT FROM AUTHOR]

Mediterranean riparian ecosystems provide key ecosystem services, such as climate regulation, water quality, and flood protection. Forest degradation and exotic species are among the main human-mediated impacts in these ecosystems, yet little is known about their interacting effect on the dynamics of soil characteristics. Here, we studied the effect of species canopy on monthly soil characteristics during one year in a riparian ecosystem in Central Spain. Soil chemical and microbiological properties were monthly recorded in five vegetation types: (1) forests dominated by the N2-fixing Alnus glutinosa, (2) shrublands dominated by A. glutinosa, (3) poplar plantations of the exotic Populus × hybrida, (4) mixed forests dominated by Fraxinus angustifolia and Salix alba, and (5) grasslands. Canopy areas showed much higher soil organic C, total N, nitrate and ammonium contents than the grassland areas. A. glutinosa forests had the highest total N, organic C, ammonium, and most probable number (MPN) of aerobic and anaerobic microorganisms followed by A. glutinosa shrublands, while mixed forests and poplar plantations had the highest nitrate content. Poplar plantations showed the lowest soil N and C content likely due to the recalcitrant litter of Populus × hybrida. N2 fixation peaked in months that differed among vegetation types. Temporal changes in soil characteristics were mostly driven by soil moisture, although the magnitude of these changes varied between canopy species. Our study highlights the importance of protecting forested areas and planting native tree species in afforestation programmes to keep the ecological integrity of riparian ecosystems. A. glutinosa is suggested as an appropriate species to improve soil fertility and stability in restoration projects. [ABSTRACT FROM AUTHOR]

Copyright of Pasos: Revista de Turismo y Patrimonio Cultural is the property of Universidad de La Laguna, Instituto Universitario de Ciencias Politicas y Sociales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Prosemas. Revista de Estudios Poéticos is the property of Universidad de Oviedo, Servicio de Publicaciones and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nucleus Animalium is the property of Fundacao Educacional de Ituverava and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Spatial variations and organism–sediment relationship are paramount subjects of soft-bottom ecology. However, these issues have been unexplored for most minor meiofaunal taxa such as tardigrades. In the present study, we explore this subject on a small tropical (~6°S) estuary. Total meiofaunal abundance ranged from 4 to 1036 individuals per 10 cm2, averaging (mean ± s.d.) 324.8 ± 245.9 individuals per 10 cm2. Nematodes dominated in both seasons, representing >70% of total abundance. Tardigrades were the second-most abundant taxon, representing 15% of the total and up to 71%. Tardigrades were represented by two species, Batillipes dandarae and B. pennaki , the latter dominating in the rainy season, and both with similar abundances in the dry season. Abundance of total meiofauna and both tardigrade species differed significantly (ANOVA; P < 0.05) among stations and in the interaction between stations and seasons, but only B. dandarae varied seasonally, with higher values occurring in the dry season. The spatial variations observed were mostly related to differences in the sediment granulometry. Environmental explanatory variables explained 72.6% of the variance of dominant meiofaunal taxa in the Redundancy Analysis. Nematodes and ostracods were mostly associated with fine and very fine sands, both tardigrades with medium sand and oligochaetes with larger size-fractions of the sediment and organic matter. The data gathered here suggest that granulometry was the most important environmental factor in the meiofaunal spatial structure in tropical estuaries and both tardigrade species were closely associated with medium sand. Spatial variations and organism–sediment relationship are paramount subjects of soft-bottom ecology. We explored this subject on a small tropical Brazilian estuary focusing on tardigrades. These animals were the second-most abundant meiofaunal taxon, being represented by Batillipes dandarae and B. pennaki. Spatial variations occurred in both dry and rainy seasons, mostly related to differences in the sediment granulometry, with both tardigrades being associated with medium sand. [ABSTRACT FROM AUTHOR]

Copyright of Revista Inovação, Projetos e Tecnologia is the property of Revista Inovacao, Projetos e Tecnologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

How have the effects of Spanish fiscal policy varied over time? Given this starting point, in this article we analyse the regime dependence of fiscal policy in Spain by estimating a vector autoregressive model within a Markov-switching framework. Our results indicate that Spain’s membership of the Economic and Monetary Union (EMU) is the most likely source of time variation in the fiscal outcomes. Accordingly, increases in the primary deficit-to-GDP ratio do not succeed in stimulating economic activity in the first regime; rather, unexpected upsurges in the primary deficit harm economic activity (non-Keynesian effect) in the second regime, which prevails since the ratification of the Maastricht Treaty. [ABSTRACT FROM AUTHOR]

Fishing is well known to curtail the size distribution of fish populations. This paper reports the discovery of small-scale spatial patterns in length appearing in several exploited species of Celtic Sea demersal 'groundfish'. These patterns match well with spatial distributions of fishing activity, estimated from vessel monitoring records taken over a period of 6 years, suggesting that this 'mobile' fish community retains a persistent impression of local-scale fishing pressure. An individual random-walk model of fish movement best matched these exploitation 'footprints' with individual movement rates set to <35 km per year. We propose that Celtic Sea groundfish may have surprisingly low movement rates for much of the year, such that fishing impact is spatially heterogeneous and related to local fishing intensity. [ABSTRACT FROM AUTHOR]

A rise in temperature will intensify the feeding links involving ectotherms in food webs. However, it is unclear how the effects will quantitatively differ between the plant-herbivore and herbivore-carnivore interface. To test how warming could differentially affect rates of herbivory and carnivory, we studied trophic interaction strength in a food chain comprised of green algae, herbivorous rotifers and carnivorous rotifers at 10, 15, 20 and 25°C. We found significant warming-induced changes in feeding by both herbivorous and carnivorous rotifers, but these responses occurred at different parts of the entire temperature gradient. The strongest response of the per capita herbivore's ingestion rate occurred due to an increase in temperature from 15 to 20°C (1.9 fold: from 834 to 1611 algal cells per h−1) and of the per capita carnivore's ingestion rate from 20 to 25°C (1.6 fold: from 1.5 to 2.5 prey h−1). Handling time, an important component of a consumer's functional response, significantly decreased from 15 to 20°C in herbivorous rotifers. In contrast, it decreased from 20 to 25°C in carnivorous rotifers. Attack rates significantly and strongly increased from 10 to 25°C in the herbivorous animals, but not at all in the carnivores. Our results exemplify how the relative forces of top-down control exerted by herbivores and carnivores may strongly shift under global warming. But warming, and its magnitude, are not the only issue: If our results would prove to be representative, shifts in ectotherm interactions will quantitatively differ when a 5°C increase starts out from a low, intermediate or high initial temperature. This would imply that warming could have different effects on the relative forces of carnivory and herbivory in habitats differing in average temperature, as would exist at different altitudes and latitudes. [ABSTRACT FROM AUTHOR]

Simultaneous limitation of plant growth by two or more nutrients is increasingly acknowledged as a common phenomenon in nature, but its cellular mechanisms are far from understood. We investigated the uptake kinetics of CO2 and phosphorus of the algae Chlamydomonas acidophila in response to growth at limiting conditions of CO2 and phosphorus. In addition, we fitted the data to four different Monod-type models: one assuming Liebigs Law of the minimum, one assuming that the affinity for the uptake of one nutrient is not influenced by the supply of the other (independent colimitation) and two where the uptake affinity for one nutrient depends on the supply of the other (dependent colimitation). In addition we asked whether the physiological response under colimitation differs from that under single nutrient limitation. We found no negative correlation between the affinities for uptake of the two nutrients, thereby rejecting a dependent colimitation. Kinetic data were supported by a better model fit assuming independent uptake of colimiting nutrients than when assuming Liebigs Law of the minimum or a dependent colimitation. Results show that cell nutrient homeostasis regulated nutrient acquisition which resulted in a trade-off in the maximum uptake rates of CO2 and phosphorus, possibly driven by space limitation on the cell membrane for porters for the different nutrients. Hence, the response to colimitation deviated from that to a single nutrient limitation. In conclusion, responses to single nutrient limitation cannot be extrapolated to situations where multiple nutrients are limiting, which calls for colimitation experiments and models to properly predict growth responses to a changing natural environment. These deviations from single nutrient limitation response under colimiting conditions and independent colimitation may also hold for other nutrients in algae and in higher plants. [ABSTRACT FROM AUTHOR]

We analyse the impact of fiscal policy shocks in the euro area as a whole, using a newly-available quarterly data set of fiscal variables for the period 1981–2007. To allow for comparability with previous results on euro-area countries and the US, we use a standard structural vector autoregressive (VAR) framework, and study the impact of aggregated and disaggregated government spending and net-tax shocks. In addition, to frame euro-area results, we apply the same methodology for the same sample period to US data. We also explore the sensitivity of the results to the inclusion of variables aiming to control for underlying financial and fiscal conditions. The main new findings are that: expansionary fiscal shocks have a short-term positive impact on GDP and private consumption, with government spending shocks entailing, in general, higher effects on economic activity than (net) tax reductions; output multipliers to government expenditure shocks are of similar size in the euro area and in the US; the persistence of a fiscal spending shock is higher in the US than in the euro area, which appears to be related to military spending in the US; and fiscal multipliers have increased over the recent past in both geographical areas. [ABSTRACT FROM AUTHOR]

A new species of Daptonema is described based upon morphological characters and 18S rRNA sequence. Daptonema matrona sp. nov. was collected in Pina Basin (north-eastern Brazil). It differs from all other species of the genus by the presence of reduced cephalic setae and straight spicules. These features require an adaptation of the generic diagnosis. Moreover, the females are characterized by intra-uterine development of the offspring, considered herein as their major autapomorphic feature. Molecular systematic analyses supported Daptonema matrona sp. nov. as a distinct genetic and evolutionary lineage. The data also indicate hypotheses of taxonomic synonymies amongst some related taxa from Xyalidae as well as the paraphyly of Daptonema. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158, 1–15. [ABSTRACT FROM AUTHOR]

Background: The loss of photosynthesis has occurred often in eukaryotic evolution, even more than its acquisition, which occurred at least nine times independently and which generated the evolution of the supergroups Archaeplastida, Rhizaria, Chromalveolata and Excavata. This secondary loss of autotrophic capability is essential to explain the evolution of eukaryotes and the high diversity of protists, which has been severely underestimated until recently. However, the ecological and evolutionary scenarios behind this evolutionary ''step back'' are still largely unknown. Methodology/Principal Findings: Using a dynamic model of heterotrophic and mixotrophic flagellates and two types of prey, large bacteria and ultramicrobacteria, we examine the influence of DOC concentration, mixotroph's photosynthetic growth rate, and external limitations of photosynthesis on the coexistence of both types of flagellates. Our key premises are: large bacteria grow faster than small ones at high DOC concentrations, and vice versa; and heterotrophic flagellates are more efficient than the mixotrophs grazing small bacteria (both empirically supported). We show that differential efficiency in bacteria grazing, which strongly depends on cell size, is a key factor to explain the loss of photosynthesis in mixotrophs (which combine photosynthesis and bacterivory) leading to purely heterotrophic lineages. Further, we show in what conditions an heterotroph mutant can coexist, or even out-compete, its mixotrophic ancestor, suggesting that bacterivory and cell size reduction may have been major triggers for the diversification of eukaryotes. Conclusions/Significance: Our results suggest that, provided the mixotroph's photosynthetic advantage is not too large, the (small) heterotroph will also dominate in nutrient-poor environments and will readily invade a community of mixotrophs and bacteria, due to its higher efficiency exploiting the ultramicrobacteria. As carbon-limited conditions were presumably widespread throughout Earth history, such a scenario may explain the numerous transitions from phototrophy to mixotrophy and further to heterotrophy within virtually all major algal lineages. We challenge prevailing concepts that affiliated the evolution of phagotrophy with eutrophic or strongly light-limited environments only. [ABSTRACT FROM AUTHOR]

We tested if the metabolic theory of ecology (MTE) correctly predicts plankton metabolism in a temperate lake, based on a long-term (about 15 years), high-frequency dataset of body size, abundance and production, using two different techniques: least squares regression and maximum likelihood. For phytoplankton, the general fit was relatively poor (r2=0.53). The assumption of the MTE on temperature dependence of metabolism was not supported, and the assumed value of ¾ of the allometric exponent was barely within 95% confidence limits. For some of the models, the value of b was significantly higher than ¾. When radiation was included as an additional predictor, it improved the model considerably (r2=0.67). Including grazing by zooplankton reduced the model residuals during the summer period, when grazing is a dominant factor. The allometric exponent had virtually no effect for phytoplankton, due to little variability in average individual size. Zooplankton production, on the other hand, was better predicted by MTE, showing stronger effects of temperature and body size, the average of which varied by a factor of more than a hundred. However, the best-fitting value of the allometric exponent for zooplankton was 0.85, and significantly higher than the ¾ predicted by the theory. The ratio of observed production to biomass for the entire plankton community declined linearly with the body size (in log-log) with a slope corresponding to a value of b=0.85. We conclude that the MTE has little predictive power for the metabolism of lacustrine plankton, in particular for phytoplankton, and especially at the scale of variability of this study, and that this could be improved by incorporating radiation into the model. [ABSTRACT FROM AUTHOR]

This paper focuses on the effects of fiscal policy in Spain analysed in a VAR context. Fiscal shocks are found to involve significant effects on GDP, private consumption, private investment, interest rates and prices. Non-Keynesian effects are observed. Moreover, evidence on the channels highlighted in the literature for such effects to arise is found, notably the effects of permanent income on consumption and investment on the demand side, coupled with the response of the equilibrium wage on the supply side affecting entrepreneurial profits and investment. The response of interest rates seems to reinforce both effects. Furthermore, the different readings of spending or taxes do not affect macroeconomic variables homogeneously. [ABSTRACT FROM AUTHOR]

Litter decomposition dynamics of three Mediterranean riverine species [ Alnus glutinosa (L.) Gaertn, Fraxinus angustifolia Vahl., and Populus x hybrida ] was studied in a 2‐year experiment in the province of Guadalajara (Spain) using the litterbag technique. Decay rates of the litter were estimated by fitting a single exponential model to the litter decomposition data. At the end of the experiment (after 485 days), the remaining litter necromass varied in the following order: Populus x hybrida > Alnus glutinosa > Fraxinus angustifolia . Litter of the three species was fast degraded; ash litter was almost totally degraded at the end of the experiment. Alder had the highest concentrations of total nitrogen and ammonium in litter, and its pattern of degradation and release to the system was different to the other two litters. This could influence the soil nutrient contents in each system as was indicated by the soil nutrient values. [ABSTRACT FROM AUTHOR]

Studies of host–parasite dynamics usually consider one, or at most two, host species, neglecting the possible effects of other species on the focal hosts and vice versa. To explore the interaction of community structure with host–parasite dynamics, we model the invasion of stable communities of varying size by a parasite. The communities are generated with random interaction coefficients and connectance 0.5. Each community is invaded by parasites with different values of virulence (disease-induced host mortality rate), specificity and transmission rate. The result of each invasion is determined by numerically simulating the dynamics of the community. We classify the outcomes by whether the parasite successfully establishes in the focal host population(s), and, if so, by the proportion of host and non-host species that go extinct as a result of the parasite's introduction. We discuss how the structure of the community and the interaction between hosts and other species affect several important processes of disease ecology: the density threshold for parasite invasion, extinction cascades caused by the parasite, and the frequency of extinctions of hosts and non-hosts. In our simulated communities, non-host species went extinct more frequently than hosts, suggesting the importance of the community context of disease. In some cases, the parasite's invasion induced regular population cycles in the previously stable community. [ABSTRACT FROM AUTHOR]

Parasites are important determinants of ecological dynamics. Despite the widespread perception that parasites (in the broad sense, including microbial pathogens) threaten species with extinction, the simplest deterministic models of parasite dynamics (i.e. of specialist parasites with density-dependent transmission) predict that parasites will always go extinct before their hosts. We review the primary theoretical mechanisms that allow disease-induced extinction and compare them with the empirical literature on parasitic threats to populations to assess the importance of different mechanisms in threatening natural populations. Small pre-epidemic population size and the presence of reservoirs are the most commonly cited factors for disease-induced extinction in empirical studies. [ABSTRACT FROM AUTHOR]

Copyright of Applied Economics Letters is the property of Routledge and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Boletin del Colegio Mexicano de Urologia is the property of Colegio Mexicano de Urologia A.C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

I present a simple model that simulates vertical variations in the light spectrum within a forest canopy. The model considers only the vertical, downward transmission of light. The light in each canopy level was assumed to consist of non-intercepted radiation and radiation intercepted within the level and transmitted. The spectrum of non-intercepted light in each canopy level is the same as that of incident light above the canopy (input parameter), whereas the spectrum of transmitted light depends on leaf area index (LAI) and the mean transmission spectrum of leaves. The model was tested in a forest and provided adequate predictions of measured values. Stronger deviations were produced in the near infrared (NIR) waveband in lower canopy levels. Multiple regression between LAI, as the dependent variable, and spectral characteristics (Blue, Green, Red and NIR intensities) had an r2 of 0.926. As a complement to other methods, I suggest light spectrum analysis as a non-destructive technique for estimating LAI in forest canopies. [ABSTRACT FROM PUBLISHER]

Presents a letter to the editor about polymorphisms associated with circulating sex hormone levels in postmenopausal women.