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1.
Rev. biol. trop ; 70(1)dic. 2022.
Artigo em Inglês | SaludCR, LILACS | ID: biblio-1423033

RESUMO

Introduction: Tropical dry forests and mangroves, two of the world's most endangered ecosystems, each host a different set of environmental conditions which may support unique assemblages of species. However, few studies have looked at the unique vertebrate biodiversity in regions where both habitats occur side-by-side. Objective: To assess the vertebrate diversity and patterns of habitat usage in a mangrove and tropical dry forest matrix in an unprotected region of Northwestern Costa Rica. Methods: The study was conducted in a 7 km2 matrix of mangrove and tropical dry forests between Cabuyal and Zapotillal bays in Northwestern Costa Rica, south of Santa Rosa National Park. From September 2017 to March 2018, we used 13 automatic camera traps over 1 498 trap days to capture species utilizing the region and assess their patterns of habitat usage both spatially and temporally. Results: Seventy vertebrate species from 42 families in 27 orders were detected, including several globally threatened species. Over half of all species were detected in only one habitat, particularly amongst avian (78 %) and mammalian (42 %) species. Tropical dry forests hosted the greatest number of unique species and supported a greater percentage of herbivores than mangrove or edge habitats, which were dominated by carnivorous and omnivorous species. Mean detections per camera trap of all species increased significantly from the coldest and wettest month (Oct) to the hottest and driest months (Jan & Feb) in tropical dry forests. Sample-based rarefaction analysis revealed that survey length was sufficient to sample the tropical dry forest and edge habitats, though mangroves require further sampling. Conclusions: Taxa found to utilize different forest types may utilize each for different stages of their life cycle, moving between areas as environmental conditions change throughout the year. General patterns of global biodiversity favoring carnivore and omnivore usage of mangrove forests was confirmed in our study.


Introducción: Los bosques secos tropicales y los manglares, dos de los ecosistemas más amenazados del mundo, albergan cada uno un grupo de condiciones ambientales que pueden albergar conjuntos únicos de especies. Sin embargo, pocos estudios han analizado la biodiversidad única de vertebrados en regiones donde ambos hábitats se encuentran uno al lado del otro. Objetivo: Evaluar la diversidad de vertebrados y los patrones de uso del hábitat en una matriz de manglar y bosque seco tropical en una región no protegida del noroeste de Costa Rica. Métodos: El estudio se realizó en una matriz de 7 km2 de manglares y bosques secos tropicales en las bahías de Cabuyal y Zapotillal en el noroeste de Costa Rica, al sur del Parque Nacional Santa Rosa. De septiembre 2017 a marzo 2018, utilizamos 13 cámaras trampa automáticas durante 1 498 días trampa para capturar especies que utilizan la región y evaluar sus patrones de uso espacial y temporal del hábitat. Resultados: Se detectaron 70 especies de vertebrados de 42 familias y 27 órdenes, incluidas varias especies amenazadas a nivel mundial. Más de la mitad de todas las especies se encontraron en un solo hábitat, particularmente aves (78 %) y mamíferos (42 %). Los bosques secos tropicales albergan el mayor número de especies únicas y sustentan un mayor porcentaje de herbívoros que los hábitats de borde de manglares, que estaban dominados u hospedados por especies carnívoras y omnívoras. Las detecciones promedio por cámara trampa de todas las especies aumentaron significativamente desde el mes más frío y húmedo (octubre) hasta los meses más cálidos y secos (enero y febrero) en los bosques secos tropicales. El análisis de rarefacción basado en muestras reveló que la duración del estudio fue suficiente para muestrear los hábitats de bosque seco tropical y de borde, aunque los manglares requieren más muestreo. Conclusiones: Se encontró que los taxones pueden usar varios tipos de bosque en las diferentes etapas de su ciclo de vida, moviéndose entre áreas a medida que las condiciones ambientales cambian a lo largo del año. En nuestro estudio se confirmaron patrones generales de la biodiversidad global que favorecen el uso de los bosques de manglar por parte de carnívoros y omnívoros.


Assuntos
Animais , Vertebrados/anatomia & histologia , Áreas Alagadas , Ecossistema Tropical , Costa Rica
2.
Ecol Evol ; 11(21): 14775-14788, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34765140

RESUMO

Ash (Fraxinus spp.) is one of the most widely distributed tree genera in North America. Populations of ash in the United States and Canada have been decimated by the introduced pest Agrilus planipennis (Coleoptera: Buprestidae; emerald ash borer), having negative impacts on both forest ecosystems and economic interests. The majority of trees succumb to attack by A. planipennis, but some trees have been found to be tolerant to infestation despite years of exposure. Restriction site-associated DNA (RAD) sequencing was used to sequence ash individuals, both tolerant and susceptible to A. planipennis attack, in order to identify single nucleotide polymorphism (SNP) patterns related to tolerance and health declines. de novo SNPs were called using SAMtools and, after filtering criteria were implemented, a set of 17,807 SNPs were generated. Principal component analysis (PCA) of SNPs aligned individual trees into clusters related to geography; however, five tolerant trees clustered together despite geographic location. A subset of 32 outlier SNPs identified within this group, as well as a subset of 17 SNPs identified based on vigor rating, are potential candidates for the selection of host tolerance. Understanding the mechanisms of host tolerance through genome-wide association has the potential to restore populations with cultivars that are able to withstand A. planipennis infestation. This study was successful in using RAD-sequencing in order to identify SNPs that could contribute to tolerance of A. planipennis. This was a first step toward uncovering the genetic basis for host tolerance to A. planipennis. Future studies are needed to identify the functionality of the loci where these SNPs occur and how they may be related to tolerance of A. planipennis attack.

3.
Animals (Basel) ; 10(6)2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32575432

RESUMO

Environmental DNA (eDNA) surveys utilize DNA shed by organisms into their environment in order to detect their presence. This technique has proven effective in many systems for detecting rare or cryptic species that require high survey effort. One potential candidate for eDNA surveying is Kirtland's Snake (Clonophis kirtlandii), a small natricine endemic to the midwestern USA and threatened throughout its range. Due to its cryptic and fossorial lifestyle, it is also a notoriously difficult snake to survey, which has limited efforts to understand its ecology. Our goal was to utilize eDNA surveys for this species to increase detection probability and improve survey efficiency to assist future conservation efforts. We conducted coverboard surveys and habitat analyses to determine the spatial and temporal activity of snakes, and used this information to collect environmental samples in areas of high and low snake activity. In addition, we spiked artificial crayfish burrows with Kirtland's Snake feces to assess the persistence of eDNA under semi-natural conditions. A quantitative PCR (qPCR) assay using a hydrolysis probe was developed to screen the environmental samples for Kirtland's Snake eDNA that excluded closely related and co-occurring species. Our field surveys showed that snakes were found in the spring during the first of two seasons, and in areas with abundant grass, herbaceous vegetation, and shrubs. We found that eDNA declines within a week under field conditions in artificial crayfish burrows. In environmental samples of crayfish burrow water and sediment, soil, and open water, a single detection was found out of 380 samples. While there may be physicochemical and biological explanations for the low detection observed, characteristics of assay performance and sampling methodology may have also increased the potential for false negatives. We explored these outcomes in an effort to refine and advance the successful application of eDNA surveying in snakes and groundwater microhabitats.

4.
Talanta ; 125: 293-300, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24840446

RESUMO

Many studies have described alternatives to the BOD5 standard method, with substantial decreases in incubation time observed. However, most of these have not maintained the features that make the BOD5 assay so relevant - a high level of substrate bio-oxidation and use of wastewater treatment plant (WWTP) sludge as the biocatalyst. Two recently described ferricyanide-mediated (FM)-BOD assays, one for trade wastes and one for WWTP influents and treated effluents, satisfy these criteria and were investigated further here for their suitability for use with diverse biocatalysts. Both FM-BOD assays responded proportionately to increasing substrate concentration with sludges from 11 different WWTPs and temporally (months to years) using sludges from a single WWTP, confirming the broad applicability of both assays. Sludges from four WWTPs were selected as biocatalysts for each FM-BOD assay to compare FM-BOD equivalent values with BOD5 (three different sludge seeds) measurements for 12 real wastewater samples (six per assay). Strong and significant relationships were established for both FM-BOD assays. This study has demonstrated that sludge sourced from many WWTPs may be used as the biocatalyst in either FM-BOD assay, as it is in the BOD5 assay. The industry potential of these findings is substantial given the widespread use of the BOD5 assay, the dramatically decreased incubation period (3-6h) and the superior analytical range of both assays compared to the standard BOD5 assay.


Assuntos
Ferricianetos/química , Oxigênio/análise , Esgotos/química , Águas Residuárias , Poluentes Químicos da Água/química , Purificação da Água/métodos , Biocatálise , Bioensaio/métodos , Catálise , Resíduos Industriais , Limite de Detecção , Teste de Materiais , Oxigênio/química , Fatores de Tempo , Eliminação de Resíduos Líquidos/métodos
5.
Sports Health ; 5(4): 367-76, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24459557

RESUMO

CONTEXT: The ability to return to elite pitching, performance, and clinical outcomes of shoulder surgery in elite baseball pitchers are not definitively established. OBJECTIVE: To determine (1) the rate of return to sport (RTS) in elite pitchers following shoulder surgery, (2) postoperative clinical outcomes upon RTS, and (3) performance upon RTS and to compare RTS rates in different types of shoulder surgery. DATA SOURCES: Using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and checklist, Medline, SciVerse Scopus, SportDiscus, and Cochrane Central Register of Controlled Trials were searched. STUDY SELECTION: Levels I-IV evidence were eligible for inclusion if performance-based (eg, RTS) and/or clinical outcome-based reporting of outcomes were reported following surgical treatment of shoulder pathology in elite pitchers (major or minor league or collegiate). DATA EXTRACTION: Subject, shoulder, and pre- and postoperative performance-based variables of interest were extracted. All shoulder surgery types were potentially inclusive (eg, open, arthroscopic, rotator cuff, labrum, biceps, acromioclavicular joint, fracture). Study methodological quality was analyzed using the Modified Coleman Methodology Score (MCMS). RESULTS: Six studies were analyzed (287 elite male pitchers [mean age, 27 years] who underwent shoulder surgery, with 99% on the dominant, throwing shoulder). MCMS was 38 (poor). Most pitchers were professional, with a mean career length of 6.58 years and postoperative clinical follow-up of 3.62 years. In 5 of 6 studies, multiple diagnoses were addressed concomitantly at surgery. Rate of RTS was 68% at mean 12 months following surgery. Twenty-two percent of Major League Baseball (MLB) pitchers never RTS in MLB. Overall performance did improve following surgery; however, this did not improve to pre-injury levels. CONCLUSION: In this systematic review, the rate of return to elite baseball pitching following surgery was established. Performance tended to decrease prior to surgery and gradually improve postoperatively, though not reaching pre-injury levels of pitching. LEVEL OF EVIDENCE: IV (systematic review of studies level I-IV evidence), therapeutic.

6.
Water Res ; 47(2): 841-9, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23200506

RESUMO

Representative and fast monitoring of wastewater influent and effluent biochemical oxygen demand (BOD) is an elusive goal for the wastewater industry and regulatory bodies alike. The present study describes a suitable assay, which incorporates activated sludge as the biocatalyst and ferricyanide as the terminal electron acceptor for respiration. A number of different sludges and sludge treatments were investigated, primarily to improve the sensitivity of the assay. A limit of detection (LOD) (2.1 mg BOD5 L⁻¹) very similar to that of the standard 5-day BOD5 method was achieved in 4 h using raw influent sludge that had been cultured overnight as the biocatalyst. Reducing the microbial concentration was the most effective means to improve sensitivity and reduce the contribution of the sludge's endogenous respiration to total ferricyanide-mediated (FM) respiration. A strong and highly significant relationship was found (n = 33; R = 0.96; p < 0.001; slope = 0.94) between BOD5 and FM-BOD equivalent values for a diverse range of samples including wastewater treatment plant (WWTP) influent and treated effluent, as well as several grey water samples. The activated sludge FM-BOD assay presented here is an exceptional surrogate method to the standard BOD5 assay, providing representative, same-day BOD analysis of WWTP samples with a comparable detection limit, a 4-fold greater analytical range and much faster analysis time. The industry appeal of such an assay is tremendous given that ~90% of all BOD5 analysis is dedicated to measurement of WWTP samples, for which this assay is specifically designed.


Assuntos
Ferricianetos/química , Indicadores e Reagentes/química , Oxigênio/análise , Águas Residuárias/química , Purificação da Água , Qualidade da Água , Biocatálise , Cidades , Eletrodos , Ferrocianetos/análise , Ferrocianetos/metabolismo , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Negativas/metabolismo , Bactérias Gram-Positivas/crescimento & desenvolvimento , Bactérias Gram-Positivas/metabolismo , Limite de Detecção , Governo Local , Oxirredução , Oxigênio/metabolismo , Queensland , Reprodutibilidade dos Testes , Resíduos Sólidos/análise , Fatores de Tempo , Águas Residuárias/microbiologia
7.
Curr Rev Musculoskelet Med ; 5(3): 244-53, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22814674

RESUMO

Young patients with cartilage defects in the hip present a complex problem for the treating physician with limited treatment modalities available. Cartilage repair/replacement techniques have shown promising results in other joints, however, the literature regarding the hip joint is limited. The purpose of the current study is to conduct a systematic review of clinical outcomes following various treatments for chondral lesions of the hip and define the techniques for the treatment of these cartilage defects. The full manuscripts of 15 studies were reviewed for this systematic review including case studies, case series, and clinical studies. A variety of techniques have been reported for the treatment of symptomatic chondral lesions in the hip. Microfracture, cartilage repair, autologous chondrocyte implantation, mosaicplasty, and osteochondral allografting have all been used in very limited case series. Although good results have been reported, most studies lack both a control group and a large number of patients. However, the reported results in this article do provide a good foundation for treatments and stimulant for further study in an inherently difficult to treat young patient population with articular cartilage defects in the hip.

8.
Water Res ; 44(20): 5981-8, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20716458

RESUMO

Activated sludge was successfully incorporated as the biocatalyst in the fast, ferricyanide-mediated biochemical oxygen demand (FM-BOD) bioassay. Sludge preparation procedures were optimized for three potential biocatalysts; aeration basin mixed liquor, aerobic digester sludge and return activated sludge. Following a 24h starving period, the return activated sludge and mixed liquor sludges reported the highest oxidative degradation of a standard glucose/glutamic acid (GGA) mixture and the return activated sludge also recorded the lowest endogenous FM-respiration rate. Dynamic working ranges up to 170 mg BOD(5)L(-1) for OECD standard solutions and 300mg BOD(5)L(-1) for GGA were obtained. This is a considerable improvement upon the BOD(5) standard assay and most other rapid BOD techniques. Time-series ferricyanide-mediated oxidation of the OECD(170) standard approached that of the GGA(198) standard after 3-6h. This is noteworthy given the OECD standard is formulated as a synthetic sewage analogue. A highly significant correlation with the BOD(5) standard method (n=35, p<0.001, R=0.952) was observed for a wide diversity of real wastewater samples. The mean degradation efficiency was indistinguishable from that observed for the BOD(5) assay. These results demonstrate that the activated sludge FM-BOD assay may be used for simple, same-day BOD analysis of wastewaters.


Assuntos
Bioensaio/métodos , Ferricianetos/metabolismo , Oxigênio/metabolismo , Esgotos/química , Oxigênio/química , Eliminação de Resíduos Líquidos
9.
Oecologia ; 130(1): 44-52, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28547024

RESUMO

Trade-offs between traits are a fundamental component of life history theory. However, because individuals may differ in the amount of energy available for allocation between traits, expected negative relationships are often difficult to detect or may become positive. The latter can occur when both traits are phenotypically plastic in response to variation in environmental productivity. We tested this hypothesis by analyzing expected trade-offs between egg mass and clutch size, and total clutch mass and post-nesting condition, in a population of Galápagos lava lizards (Microlophus delanonis) that experienced marked annual and seasonal variation in rainfall. Due to its close relationship with overall mass (reproductive plus post-nesting mass), we considered rainfall to be a suitable indicator of environmental productivity. Females that reproduced during periods of low rainfall produced smaller and fewer eggs, and had lower post-nesting body mass independent of body size (snout-vent length). This pattern was found in comparisons both between and within individuals that nested in dry and wet periods, respectively. The relationships between egg mass and clutch size, and total clutch mass and post-nesting mass, were positive when data were combined across years and seasons. Restriction of the analysis to comparisons within time periods (in effect, holding productivity constant), resulted in negative correlations between egg mass and clutch size, and weakened relationships between total clutch mass and post-nesting mass. We conclude that phenotypic plasticity in reproduction obscures life history trade-offs and that plasticity may be more important to the fitness of females than a particular value for an individual reproductive trait.

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