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1.
New Phytol ; 227(2): 588-600, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32012277

RESUMO

Emergent diseases are an increasing problem in forests worldwide. Exotic pathogens are now threatening forests where pathogens have not traditionally been considered to be major ecological drivers of tree demography, such as water-limited Mediterranean forests. However, how pathogens might limit regeneration in invaded forests is largely unknown. Here we used fungicide to analyse the impact of soil-borne oomycete pathogens on seedling establishment at community level in Mediterranean forests invaded by the exotic oomycete Phytophthora cinnamomi. Fungicide effects were modelled as a function of the tree neighbourhood composition, the seed mass of the target species, and the abiotic environment. Fungicide application had positive effects on seedling performance that varied in magnitude and spatial structure among coexisting species. Seed mass predicted fungicide effects on seedling emergence, but not on survival or growth. Positive fungicide effects were modulated by levels of abiotic resources, mainly water, increasing with soil moisture. Our results support a novel role for soil-borne oomycete pathogens as one more axis of the regeneration niche of woody species in water-limited forests. Given the increasing numbers of exotic oomycete pathogens worldwide, more research is needed to understand the role of this relevant microbial group as a factor shaping seedling establishment.


Assuntos
Phytophthora , Solo , Florestas , Plântula , Árvores
2.
Ecology ; 98(7): 1908-1921, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28419433

RESUMO

Plant-soil feedbacks (PSFs) play a relevant role as drivers of species abundance, coexistence, and succession in plant communities. However, the potential contribution of PSFs to community dynamics in changing forest ecosystems affected by global change drivers is still largely unexplored. We measured the direction, strength and nature (biological vs. chemical) of PSFs experienced by coexisting tree species in two types of declining Quercus suber forests of southwestern Spain (open woodland vs. closed forest) invaded by the exotic soil pathogen Phytophthora cinnamomi. To test PSFs in a realistic community context, we focused not only on individual PSFs (i.e., comparing the growth of a tree species on conspecific vs. heterospecific soil) but also calculated net-pairwise PSFs by comparing performance of coexisting tree species on their own and each other's soils. We hypothesized that the decline and death of Q. suber would alter the direction and strength of individual and net-pairwise PSFs due to the associated changes in soil nutrients and microbial communities, with implications for recruitment dynamics and species coexistence. In support of our hypothesis, we found that the decline of Q. suber translated into substantial alterations of individual and net-pairwise PSFs, which shifted from mostly neutral to significantly positive or negative, depending on the forest type. In both cases however the identified PSFs benefited other species more than Q. suber (i.e., heterospecific positive PSF in the open woodland, conspecific negative PSF in the closed forest). Our results supported PSFs driven by changes in chemical soil properties (mainly phosphorus) and arbuscular mycorrhizal fungi, but not in pathogen abundance. Overall, our study suggests that PSFs might reinforce the loss of dominance of Q. suber in declining forests invaded by P. cinnamomi by promoting the relative performance of non-declining coexisting species. More generally, our results indicate an increase in the strength of net PSFs as natural forests become disturbed by global change drivers (e.g., invasive species), suggesting an increasingly important role of PSFs in forest community dynamics in the near future.


Assuntos
Ecossistema , Plantas , Solo , Florestas , Micorrizas , Espanha , Árvores
3.
BMC Public Health ; 17(1): 94, 2017 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-28103843

RESUMO

BACKGROUND: An increase of sedentary behaviors far from the Mediterranean lifestyle is happening in spite of the impact on health. The aims of this study were to describe sedentary behaviors in children and adolescents. METHODS: A representative sample of 424 Spanish children and adolescents (38% females) involved in the ANIBES study was analyzed regarding their sedentary behaviors, together with the availability of televisions, computers, and consoles by means of the HELENA sedentary behavior questionnaire. RESULTS: For the total sample of children, 49.3% during weekdays and 84% during weekends did not meet the recommendation of less than 2 hours of screen viewing per day. The use of TV was higher during weekdays (p < 0.05) and there were significant differences between adolescents and children (16.9 vs. 25.1%, p < 0.05). The use of computer, console games and of internet for non-study reasons was higher during weekends (p < 0.001). Adolescents played more computer games and used more internet for non-study reasons than children during both weekdays and weekends (p < 0.05 and p < 0.001, respectively). The use of internet for academic reasons was lower in children (p < 0.001) than adolescents during weekends; however, no significant differences were found between sexes. In addition, more than 30% of the children and adolescents had at least one electronic device in their bedrooms. CONCLUSIONS: Spanish children and adolescents are not meeting the recommendations regarding the maximum of screen viewing (<2 h/day), especially during the weekend, for all of sedentary behaviors. Urgent strategies and intervention studies are needed to reduce sedentary behavior in young people.


Assuntos
Computadores/estatística & dados numéricos , Internet/estatística & dados numéricos , Comportamento Sedentário , Televisão/estatística & dados numéricos , Jogos de Vídeo/estatística & dados numéricos , Adolescente , Comportamento do Adolescente , Criança , Feminino , Humanos , Masculino , Espanha , Inquéritos e Questionários , Fatores de Tempo
4.
Polymers (Basel) ; 15(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36987361

RESUMO

Global polystyrene (PS) production has been influenced by the lightness and heat resistance this material offers in different applications, such as construction and packaging. However, population growth and the lack of PS recycling lead to a large waste generation, affecting the environment. Pyrolysis has been recognized as an effective recycling method, converting PS waste into valuable products in the chemical industry. The present work addresses a systematic, bibliometric, and statistical analysis of results carried out from 2015 to 2022, making an extensive critique of the most influential operation parameters in the thermo-catalytic pyrolysis of PS and its waste. The systematic study showed that the conversion of PS into a liquid with high aromatic content (84.75% of styrene) can be achieved by pyrolysis. Discussion of PS as fuel is described compared to commercial fuels. In addition, PS favors the production of liquid fuel when subjected to co-pyrolysis with biomass, improving its properties such as viscosity and energy content. A statistical analysis of the data compilation was also discussed, evaluating the influence of temperature, reactor design, and catalysts on product yield.

5.
New Phytol ; 194(4): 1014-1024, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22428751

RESUMO

Soil-borne pathogens are a key component of the belowground community because of the significance of their ecological and socio-economic impacts. However, very little is known about the complexity of their distribution patterns in natural systems. Here, we explored the patterns, causes and ecological consequences of spatial variability in pathogen abundance in Mediterranean forests affected by oak decline. We used spatially explicit neighborhood models to predict the abundance of soil-borne pathogen species (Phytophthora cinnamomi, Pythium spiculum and Pythium spp.) as a function of local abiotic conditions (soil texture) and the characteristics of the tree and shrub neighborhoods (species composition, size and health status). The implications of pathogen abundance for tree seedling performance were explored by conducting a sowing experiment in the same locations in which pathogen abundance was quantified. Pathogen abundance in the forest soil was not randomly distributed, but exhibited spatially predictable patterns influenced by both abiotic and, particularly, biotic factors (tree and shrub species). Pathogen abundance reduced seedling emergence and survival, but not in all sites or tree species. Our findings suggest that heterogeneous spatial patterns of pathogen abundance at fine spatial scale can be important for the dynamics and restoration of declining Mediterranean forests.


Assuntos
Modelos Biológicos , Quercus/microbiologia , Plântula/microbiologia , Microbiologia do Solo , Interações Hospedeiro-Patógeno , Região do Mediterrâneo , Phytophthora/fisiologia , Pythium/fisiologia
6.
Polymers (Basel) ; 14(22)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36433086

RESUMO

The use of plastic as material in various applications has been essential in the evolution of the technology industry and human society since 1950. Therefore, their production and waste generation are high due to population growth. Pyrolysis is an effective recycling method for treating plastic waste because it can recover valuable products for the chemical and petrochemical industry. This work addresses the thermal pyrolysis of expanded polystyrene (EPS) post-industrial waste in a semi-batch reactor. The influence of reaction temperature (350-500 °C) and heating rate (4-40 °C min-1) on the liquid conversion yields and physicochemical properties was studied based on a multilevel factorial statistical analysis. In addition, the analysis of the obtaining of mono-aromatics such as styrene, toluene, benzene, ethylbenzene, and α-methyl styrene was performed. Hydrocarbon liquid yields of 76.5-93% were achieved at reaction temperatures between 350 and 450 °C, respectively. Styrene yields reached up to 72% at 450 °C and a heating rate of 25 °C min-1. Finally, the potential application of the products obtained is discussed by proposing the minimization of EPS waste via pyrolysis.

7.
Ecology ; 102(8): e03430, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34105778

RESUMO

Interactions among plant species and their soil biota drive plant-soil feedbacks (PSFs) that play a major role in the dynamics and diversity of plant communities. Among the different components of the soil community, pathogens are considered to be the main drivers of negative PSFs. Despite this, the number of studies that have experimentally quantified the contribution of soil pathogens to PSFs remains considerably low. Here we conducted a greenhouse experiment with oomycete-specific fungicide to quantify the contribution of soil pathogens, and particularly oomycete pathogens, to individual and pairwise PSFs in forest communities. We used as a case study Mediterranean mixed forests dominated by Quercus suber and invaded by the oomycete pathogen Phytophthora cinnamomi. The fungicide treatment was crossed with a competition treatment to explore how conspecific neighbors might modify pathogen effects. To place the results of the experiment in a wider context, we also conducted a systematic review of published papers that explicitly used fungicide to explore the role of pathogens in PSF experiments. Our experimental results showed that oomycete pathogens were the main drivers of individual PSFs in the study forests. Oomycete effects varied among tree species according to their susceptibility to P. cinnamomi, driving negative PSFs in the highly susceptible Q. suber but not in the coexistent Olea europaea. Oomycete-driven PSFs were not modified by intraspecific competition. Oomycete pathogens were also major contributors to negative pairwise PSFs assumed to promote species coexistence. Results from the systematic review supported the novelty of our experimental results, since only three studies had previously used oomycete-specific fungicide in a PSF context and none in systems invaded by exotic oomycetes. Overall, our results provide novel evidence of oomycete pathogens (including the exotic P. cinnamomi) as fundamental drivers of negative individual and pairwise PSFs with implications for species coexistence in invaded communities. Although in the short-term invasive pathogens might contribute to species coexistence by causing self-limitation in dominant species, strong inter-specific variation in self-limitation might undermine coexistence in the long-term. Because of the increasing number of exotic oomycetes worldwide, further attention should be given to oomycetes as drivers of PSFs in plant communities.


Assuntos
Phytophthora , Solo , Retroalimentação , Florestas , Plantas , Revisões Sistemáticas como Assunto
8.
Cir Cir ; 87(3): 299-307, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31135780

RESUMO

INTRODUCTION: The spine surgeon has knowledge and skills that allow him to make decisions when performing a surgical procedure, based on the evidence and ethical values and expectations of the patient. Any surgical procedure will be preceded by a diagnosis based on four fundamental pillars: traumatic, degenerative, vertebral destruction syndrome and deformities. Once the lesion is categorized, the surgeon will use his knowledge to identify instability or neurological compromise. When performing a surgical procedure, it should be kept in mind in the transoperative the four key objectives that will count, to achieve a satisfactory management: decompress, implement, merge and correct the sagittal balance. OBJECTIVE: To analyze the fundamental criteria in decision making, for conservative or surgical management in the spine. RESULTS: The assessment scales and the most frequent and best practices in relation to spine surgery will be analyzed, as well as the applications that will be applied and evaluated in each particular case, which will strengthen the diagnostic impression and the value forecast. CONCLUSION: Implementing the culture of using patient outcome measurements as an assessment tool helps the spine surgeon to decide on a treatment plan that can be adapted to the patient's preferences and needs. We must base our clinical objective on the stability and the neurological commitment of the patient, there being four diagnostic possibilities; which will be corrected for four fundamental objectives.


INTRODUCCIÓN: El cirujano de columna cuenta con conocimientos y habilidades que le permiten tomar decisiones al momento de realizar un procedimiento quirúrgico, basado en la evidencia, en valores éticos y en las expectativas del paciente. Cualquier procedimiento quirúrgico será precedido por el diagnóstico basado en cuatro pilares fundamentales: traumático, degenerativo, síndrome de destrucción vertebral y deformidades. Una vez categorizada la lesión, el cirujano utilizará sus conocimientos para identificar la inestabilidad o el compromiso neurológico. Al realizar un procedimiento quirúrgico, en el transoperatorio deberán tenerse en mente los cuatro objetivos fundamentales con los que contará para lograr un manejo satisfactorio: descomprimir, instrumentar, fusionar y corregir el balance sagital. OBJETIVO: Analizar los criterios fundamentales en la toma de decisión para el manejo conservador o quirúrgico en la columna vertebral. RESULTADOS: Se analizaron las escalas de medición y de evaluación más frecuentes y mayormente efectivas en relación a la cirugía de columna, mismos que obligadamente tienen que ser aplicadas y evaluadas en cada caso particular, lo cual permite fortalecer la impresión diagnóstica y el valor pronóstico. CONCLUSIÓN: Implementar la cultura del uso de mediciones de resultados de pacientes como instrumento de evaluación ayuda al cirujano de columna a decidir un plan de tratamiento que pueda adecuarse a las preferencias y las necesidades del paciente. Debemos fundamentar nuestro objetivo clínico en la estabilidad y el compromiso neurológico del paciente, existiendo cuatro posibilidades diagnósticas, que se corregirán para cuatro objetivos fundamentales.


Assuntos
Tomada de Decisão Clínica , Procedimentos Ortopédicos/normas , Coluna Vertebral/cirurgia , Humanos , Guias de Prática Clínica como Assunto
9.
Cir Cir ; 87(2): 164-169, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30768072

RESUMO

OBJECTIVE: Establish whether the use of starch in hip arthroplasty is a risk factor for excessive surgical bleeding and requirement of red blood cell transfusion. METHOD: Analytical observational retrospective study in 240 patients who underwent primary total hip arthroplasty from January 2015 to January 2016. Two groups were formed: starch (94 patients) and non-starch (146 patients). Age, sex, body mass index, preoperative and postoperative hemoglobin, red cell transfusion and surgical bleeding was analyzed. RESULTS: Starchy group had increased risk of excessive surgical bleeding (OR: 3.58; 95% CI: 2.05- 6.26) and red blood cells transfusion (OR: 3.12; 95% CI: 1.76 -5.5). In the starch group average surgical bleeding was 396 ml (SD: ± 234.94) and a decrease in hemoglobin of 4.6 g/dl (SD± 1.38). The control group had an average bleeding of 271.8 ml (SD: ± 139.22) and decrease in hemoglobin of 3.34 g/dl (SD: ± 1.4). DISCUSSION: The starch group had higher surgical bleeding and required more often red blood cells transfusion than the non-starch group. We suggest to take in account the possible complications related to the use hydroxyethyl starch.


OBJETIVO: Determinar si el uso de almidón en la artroplastia de cadera es un factor de riesgo para el sangrado transquirúrgico excesivo y el uso de concentrados eritrocitarios. MÉTODO: Estudio retrospectivo observacional analítico de 240 pacientes sometidos a artroplastia total de cadera primaria desde enero de 2015 hasta enero de 2016. Se integraron dos grupos: almidón (94 pacientes) y no almidón (146 pacientes). Se analizaron la edad, el sexo, el índice de masa corporal, la hemoglobina prequirúrgica y posquirúrgica, el uso de concentrados eritrocitarios y el sangrado transquirúrgico. RESULTADOS: El grupo con almidón tuvo mayor riesgo de sangrado transquirúrgico excesivo (odds ratio [OR]: 3.58; intervalo de confianza del 95% [IC 95%]: 2.05- 6.26) y de transfusión de concentrados eritrocitarios (OR: 3.12; IC 95%: 1.76-5.5). En el grupo con almidón hubo una media de sangrado transquirúrgico de 396 ml (desviación estándar [DE]: ± 234.94) y una disminución de la hemoglobina de 4.6 g/dl (DE: ± 1.38); en el grupo de no almidón hubo una media de sangrado de 271.8 ml (DE: ± 139.22) y una disminución de la hemoglobina de 3.34 g/dl (DE: ± 1.4). DISCUSIÓN: Los pacientes con almidón presentaron mayor sangrado transquirúrgico y requirieron en más ocasiones la transfusión de hemoderivados que los del grupo control, por lo que sugerimos considerar las posibles complicaciones relacionadas con el uso de hidroxietilalmidón.


Assuntos
Artroplastia de Quadril , Perda Sanguínea Cirúrgica , Derivados de Hidroxietil Amido/efeitos adversos , Substitutos do Plasma/efeitos adversos , Fatores Etários , Idoso , Índice de Massa Corporal , Estudos de Casos e Controles , Intervalos de Confiança , Transfusão de Eritrócitos , Feminino , Hemoglobina A/análise , Humanos , Derivados de Hidroxietil Amido/administração & dosagem , Masculino , Razão de Chances , Substitutos do Plasma/administração & dosagem , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais
10.
Nutrients ; 9(3)2017 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-28335441

RESUMO

The consumption of total and individual sugars is controversial and little is known about consumption and dietary sources in Spain. The purpose was to examine free and intrinsic sugar intake and food and beverage sources. The ANIBES Study (Anthropometry, Intake and Energy Balance in Spain), a cross-sectional study of a representative sample of the Spanish population (9-75 years old; n = 2009) carried out in 2013, was used. Food and beverage records were obtained by a three-day dietary record by using a tablet device. The median total sugar intake was 71.5 g/day (17% Total Energy, TE), the intrinsic sugar intake was 38.3 g/day (9.6% TE), and the free sugar was 28.8 g/day (7.3% TE). Total sugar intake (free and intrinsic) was higher in men than in women for all age groups, although in terms of the contribution to total energy intake, the opposite was observed. Differences were observed for free sugar consumption dependent on age and marked differences (up to two-fold) were observed when considering the percent TE, which was much higher in children and adolescents. For the intrinsic sugar, however, a higher contribution to TE was observed in the elderly. The major sources of intrinsic sugars were fruits (31.8%), milks (19.6%), juices and nectars (11.1%), vegetables (9.89%), yogurt and fermented milk (7.18%), low-alcohol-content beverages (4,94%), bread (2.91%), and sugar soft drinks (2.24%), greater than 90% from diet contribution. As for free sugars, sources were sugar soft drinks (25.5%), sugar (17.8%), bakery and pastry items (15.2%), chocolates (11.4%), yogurt and fermented milk (6.44%), other dairy products (5.99%), jams (3.58%), juices and nectars (2.91%), and breakfast cereals and cereal bars (2.78%), summing up to 90% of the contribution. The present study demonstrates that only a moderate percentage of the Spanish population adhered to the present recommendations for total sugar intake, and urgent efforts are needed to improve diet quality in the youngest populations.


Assuntos
Dieta , Carboidratos da Dieta/administração & dosagem , Adoçantes Calóricos/administração & dosagem , Adoçantes Calóricos/análise , Adolescente , Adulto , Idoso , Bebidas , Bebidas Gaseificadas , Criança , Estudos Transversais , Laticínios , Registros de Dieta , Feminino , Qualidade dos Alimentos , Frutas , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Espanha , Verduras , Adulto Jovem
11.
PLoS One ; 10(2): e0117827, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25706723

RESUMO

In forests, the vulnerable seedling stage is largely influenced by the canopy, which modifies the surrounding environment. Consequently, any alteration in the characteristics of the canopy, such as those promoted by forest dieback, might impact regeneration dynamics. Our work analyzes the interaction between canopy neighbors and seedlings in Mediterranean forests affected by the decline of their dominant species (Quercus suber). Our objective was to understand how the impacts of neighbor trees and shrubs on recruitment could affect future dynamics of these declining forests. Seeds of the three dominant tree species (Quercus suber, Olea europaea and Quercus canariensis) were sown in six sites during two consecutive years. Using a spatially-explicit, neighborhood approach we developed models that explained the observed spatial variation in seedling emergence, survival, growth and photochemical efficiency as a function of the size, identity, health, abundance and distribution of adult trees and shrubs in the neighborhood. We found strong neighborhood effects for all the performance estimators, particularly seedling emergence and survival. Tree neighbors positively affected emergence, independently of species identity or health. Alternatively, seedling survival was much lower in neighborhoods dominated by defoliated and dead Q. suber trees than in neighborhoods dominated by healthy trees. For the two oak species, these negative effects were consistent over the three years of the experimental seedlings. These results indicate that ongoing changes in species' relative abundance and canopy trees' health might alter the successional trajectories of Mediterranean oak-forests through neighbor-specific impacts on seedlings. The recruitment failure of dominant late-successional oaks in the gaps opened after Q. suber death would indirectly favor the establishment of other coexisting woody species, such as drought-tolerant shrubs. This could lead current forests to shift into open systems with lower tree cover. Adult canopy decline would therefore represent an additional factor threatening the recruitment of Quercus forests worldwide.


Assuntos
Quercus/crescimento & desenvolvimento , Secas , Ecossistema , Florestas , Região do Mediterrâneo , Plântula/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento
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