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1.
Sci Total Environ ; 926: 172104, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38556016

RESUMO

Saltmarshes are a crucial component of the coastal carbon (C) system and provide a natural climate regulation service through the accumulation and long-term storage of organic carbon (OC) in their soils. These coastal ecosystems are under growing pressure from a changing climate and increasing anthropogenic disturbance. To manage and protect these ecosystems for C and to allow their inclusion in emissions and natural-capital accounting, as well as carbon markets, accurate and reliable estimates of OC accumulation are required. However, globally, such data are rare or of varying quality. Here, we quantify sedimentation rates and OC densities for 21 saltmarshes in Great Britain (GB). We estimate that, on average, saltmarshes accumulate OC at a rate of 110.88 ± 43.12 g C m-2 yr-1. This is considerably less than widely applied global saltmarsh averages. It is therefore highly likely that the contribution of northern European saltmarshes to global saltmarsh OC accumulation has been significantly overestimated. Taking account of the climatic, geomorphological, oceanographic, and ecological characteristics of all GB saltmarshes and the areal extent of different saltmarsh zones, we estimate that the 451.65 km2 of GB saltmarsh accumulates 46,563 ± 4353 t of OC annually. These low OC accumulation rates underline the importance of the 5.20 ± 0.65 million tonnes of OC already stored in these vulnerable coastal ecosystems. Going forward the protection and preservation of the existing stores of OC in GB saltmarshes must be a priority for the UK as this will provide climate benefits through avoided emissions several times more significant than the annual accumulation of OC in these ecosystems.

2.
Sci Data ; 10(1): 797, 2023 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-37952023

RESUMO

Tidal marshes store large amounts of organic carbon in their soils. Field data quantifying soil organic carbon (SOC) stocks provide an important resource for researchers, natural resource managers, and policy-makers working towards the protection, restoration, and valuation of these ecosystems. We collated a global dataset of tidal marsh soil organic carbon (MarSOC) from 99 studies that includes location, soil depth, site name, dry bulk density, SOC, and/or soil organic matter (SOM). The MarSOC dataset includes 17,454 data points from 2,329 unique locations, and 29 countries. We generated a general transfer function for the conversion of SOM to SOC. Using this data we estimated a median (± median absolute deviation) value of 79.2 ± 38.1 Mg SOC ha-1 in the top 30 cm and 231 ± 134 Mg SOC ha-1 in the top 1 m of tidal marsh soils globally. This data can serve as a basis for future work, and may contribute to incorporation of tidal marsh ecosystems into climate change mitigation and adaptation strategies and policies.

3.
Crit Care Nurse ; 42(5): 14-21, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36180061

RESUMO

BACKGROUND: Medical device-related pressure injuries attributed to oxygen delivery devices are common yet preventable. Pressure injuries increase hospital costs, patients' length of stay, and mortality rates. OBJECTIVE: To decrease medical device-related pressure injuries by transitioning patients from an over-the-nose noninvasive ventilation mask to a single-headset, interchangeable under-the-nose and over-the-nose noninvasive ventilation mask; replacing polyvinyl chloride nasal cannulas with a softer nasal cannula; and providing staff education on preventing pressure injuries related to oxygen delivery devices. METHODS: The project was implemented on 4 adult inpatient units with a total of 75 inpatient beds at an academic medical center. Interventions included implementing the trial noninvasive ventilation masks and nasal cannulas, alternating masks every 4 hours, relocating protective dressings, promoting the use of protective dressings for over-the-nose oral-nasal masks, and educating health care staff. RESULTS: In the 2 months before implementation (September and October 2020), 1 medical device-related pressure injury was caused by a noninvasive ventilation mask and 4 injuries were caused by nasal cannulas. During the 2 months of trial implementation (November and December 2020), no pressure injuries developed in patients using the trial devices. DISCUSSION: The interventions implemented had clinically relevant results. A larger sample size would be necessary to determine statistical significance. Postintervention data indicated a need for further education on evidence-based practice guidelines on mask alternation and use of preventive dressings to bolster compliance. CONCLUSION: Following institutional approval, all noninvasive ventilation masks and nasal cannulas were transitioned to the trial devices at the study institution.


Assuntos
Ventilação não Invasiva , Úlcera por Pressão , Adulto , Humanos , Cânula/efeitos adversos , Máscaras/efeitos adversos , Ventilação não Invasiva/efeitos adversos , Ventilação não Invasiva/métodos , Oxigênio , Cloreto de Polivinila , Úlcera por Pressão/prevenção & controle
4.
Sci Data ; 6(1): 165, 2019 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-31477737

RESUMO

Rapid changes in ocean circulation and climate have been observed in marine-sediment and ice cores over the last glacial period and deglaciation, highlighting the non-linear character of the climate system and underlining the possibility of rapid climate shifts in response to anthropogenic greenhouse gas forcing. To date, these rapid changes in climate and ocean circulation are still not fully explained. One obstacle hindering progress in our understanding of the interactions between past ocean circulation and climate changes is the difficulty of accurately dating marine cores. Here, we present a set of 92 marine sediment cores from the Atlantic Ocean for which we have established age-depth models that are consistent with the Greenland GICC05 ice core chronology, and computed the associated dating uncertainties, using a new deposition modeling technique. This is the first set of consistently dated marine sediment cores enabling paleoclimate scientists to evaluate leads/lags between circulation and climate changes over vast regions of the Atlantic Ocean. Moreover, this data set is of direct use in paleoclimate modeling studies.

5.
PLoS One ; 14(8): e0220046, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31433797

RESUMO

Foraminifera are expected to be particularly susceptible to future changes in ocean carbonate chemistry as a function of increased atmospheric CO2. Studies in an experimental recirculating seawater system were performed with a dominant benthic foraminiferal species collected from intertidal mudflats. We investigated the experimental impacts of ocean acidification on survival, growth/calcification, morphology and the biometric features of a calcareous species Elphidium williamsoni. Foraminifera were exposed for 6 weeks to four different pH treatments that replicated future scenarios of a high CO2 atmosphere resulting in lower seawater pH. Results revealed that declining seawater pH caused a decline in foraminiferal survival rate and growth/calcification (mainly through test weight reduction). Scanning electron microscopy image analysis of live specimens at the end of the experimental period show changes in foraminiferal morphology with clear signs of corrosion and cracking on the test surface, septal bridges, sutures and feeding structures of specimens exposed to the lowest pH conditions. These findings suggest that the morphological changes observed in shell feeding structures may serve to alter: (1) foraminiferal feeding efficiency and their long-term ecological competitiveness, (2) the energy transferred within the benthic food web with a subsequent shift in benthic community structures and (3) carbon cycling and total CaCO3 production, both highly significant processes in coastal waters. These experimental results open-up the possibility of modelling future impacts of ocean acidification on both calcification and dissolution in benthic foraminifera within mid-latitude intertidal environments, with potential implications for understanding the changing marine carbon cycle.


Assuntos
Calcificação Fisiológica/efeitos dos fármacos , Foraminíferos/efeitos dos fármacos , Foraminíferos/crescimento & desenvolvimento , Água do Mar/química , Carbonatos/análise , Carbonatos/farmacologia , Foraminíferos/fisiologia , Concentração de Íons de Hidrogênio , Análise de Sobrevida , Fatores de Tempo
6.
J Tissue Eng Regen Med ; 12(12): 2309-2318, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30353675

RESUMO

The demand for skin rejuvenation procedures has progressively increased in the past decade. Additionally, clinical trials have shown that current therapies might cause downtime and side effects in patients including prolonged erythema, scarring, and dyspigmentation. The goal of this study was to explore the effect of partial irreversible electroporation (pIRE) with pulsed electric fields in aged skin rejuvenation as a novel, non-invasive skin resurfacing technique. In this study, we used an experimental model of aged rats. We showed that treatment with pIRE promoted keratinocyte proliferation and blood flow in aged rat skin. We also found significant evidence indicating that pIRE reformed the dermal extracellular matrix (ECM). Both the collagen protein and fibre density in aged skin increased after pIRE administration. Furthermore, using an image-processing algorithm, we found that the collagen fibre orientation in the histological sections did not change, indicating a lack of scar formation in the treated areas. The results showed that pIRE approach could effectively stimulate keratinocyte proliferation, ECM synthesis, and angiogenesis in an aged rat model.


Assuntos
Proliferação de Células , Eletroporação , Matriz Extracelular/metabolismo , Queratinócitos/metabolismo , Rejuvenescimento , Envelhecimento da Pele , Animais , Matriz Extracelular/patologia , Feminino , Humanos , Queratinócitos/patologia , Ratos , Ratos Sprague-Dawley
7.
Zootaxa ; 4121(1): 1-48, 2016 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-27395201

RESUMO

Extensive new collections of latrunculid sponges from British Columbia, the Aleutian Islands, and the Gulf of Alaska, have extended the distributions of known species Latrunculia oparinae Samaai & Krasokhin, 2002, from the Russian Sea of Okhotsk, L. velera Lehnert et al., 2006, from the Aleutian Islands, and L. austini Samaai et al., 2006, from British Columbia. New material has facilitated detailed re-descriptions of these species and in situ images have improved our understanding of their living morphology and ecology. Several new species of Latrunculia were discovered within these collections: sympatric species Latrunculia hamanni sp. nov. and L. oparinae are described here and differentiated from each other by various field characteristics, and L. lincfreesei sp. nov. is described from the Gulf of Alaska. In terms of their higher systematics, L. austini and L. hamanni sp. nov. are recognisable within the subgenus Latrunculia du Bocage, 1869, and L. lincfreesei sp. nov. in subgenus Biannulata Samaai et al., 2006. A third subgenus, Uniannulata subgen. nov., is proposed for L. oparinae, L. velera and several fossil species in southern New Zealand and Western Australian Eocene fossiliferous sediments. In all of these species the subsidiary whorl, apical whorl, and apex of the anisodiscorhabd are fused. Living species of Uniannulata subgen. nov. are thus far restricted to the North Pacific Ocean. A new genus, Bomba gen. nov., is proposed for a rare latrunculid species, Bomba endeavourensis gen. et sp. nov., discovered in deep waters on British Columbia's Endeavour Ridge. Finally, Latrunclava gen. nov. is proposed for species with long, sceptre-like anisoconicorhabds in addition to the typical, smaller anisodiscorhabds; Latrunclava imago gen. et sp. nov. is described from the central Aleutian Islands.


Assuntos
Poríferos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Austrália , Tamanho Corporal , Ecossistema , Fósseis/anatomia & histologia , Nova Zelândia , Tamanho do Órgão , Poríferos/anatomia & histologia , Poríferos/crescimento & desenvolvimento
8.
PLoS One ; 11(7): e0158754, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27388271

RESUMO

A robust and consistent taxonomy underpins the use of fossil material in palaeoenvironmental research and long-term assessment of biodiversity. This study presents a new integrated taxonomic protocol for benthic foraminifera by unequivocally reconciling the traditional taxonomic name to a specific genetic type. To implement this protocol, a fragment of the small subunit ribosomal RNA (SSU rRNA) gene is used in combination with 16 quantitative morphometric variables to fully characterise the benthic foraminiferal species concept of Elphidium williamsoni Haynes, 1973. A combination of live contemporary topotypic specimens, original type specimens and specimens of genetic outliers were utilised in this study. Through a series of multivariate statistical tests we illustrate that genetically characterised topotype specimens are morphologically congruent with both the holotype and paratype specimens of E. williamsoni Haynes, 1973. We present the first clear link between morphologically characterised type material and the unique SSU rRNA genetic type of E. williamsoni. This example provides a standard framework for the benthic foraminifera which bridges the current discontinuity between molecular and morphological lines of evidence, allowing integration with the traditional Linnaean roots of nomenclature to offer a new prospect for taxonomic stability.


Assuntos
Classificação , Foraminíferos/classificação , RNA Ribossômico/análise , Oceano Atlântico , Biodiversidade , DNA de Protozoário/genética , DNA Ribossômico/genética , Fósseis , Geografia , Microscopia Eletrônica de Varredura , Análise Multivariada , Paleontologia/métodos , Filogenia , Análise de Componente Principal , Subunidades Ribossômicas Menores
9.
Am J Sports Med ; 43(12): 3022-6, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26493338

RESUMO

BACKGROUND: Anterior cruciate ligament (ACL) injuries are common and potentially career ending in the National Football League (NFL). Although statistical performance has been demonstrated after ACL reconstruction, functional performance is not well defined. PURPOSE/HYPOTHESIS: The purpose of this study was to determine the functional performance of NFL combine participants after ACL reconstruction compared with an age-, size-, and position-matched control group. The hypothesis was that there would be no difference between players after ACL reconstruction as compared with controls in functional athletic performance. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 98 NFL-caliber athletes who had undergone primary ACL reconstruction and participated in the NFL scouting combine between 2010 and 2014 were reviewed and compared with an age-, size-, and position-matched control group. Data recorded for each player included a 40-yard dash, vertical leap, broad jump, shuttle drill, and 3-cone drill. RESULTS: With regard to speed and acceleration, the mean 40-yard dash time for ACL-reconstructed players was 4.74 seconds (range, 4.33-5.55 seconds) compared with controls at 4.74 seconds (range, 4.34-5.38 seconds; P = .96). Jumping performance was also similar, with a mean vertical leap for ACL-reconstructed players of 33.35 inches (range, 23-43 inches) and broad jump of 113.9 inches (range, 96-136 inches) compared with respective values for the controls of 33.22 inches (range, 23.5-43.5 inches; P = .84) and 113.9 inches (range, 92-134 inches; P = .99). Agility and quickness testing measures also did not show a statistically significantly difference, with ACL-reconstructed players performing the shuttle drill in 4.37 seconds (range, 4.02-4.84 seconds) and the 3-cone drill in 7.16 seconds (range, 6.45-8.14 seconds), respectively, compared with respective times for the controls of 4.37 seconds (range, 3.96-5.00 seconds; P = .91) and 7.18 seconds (range, 6.64-8.24 seconds; P = .75). CONCLUSION: This study suggests that after ACL reconstruction, high-caliber athletes can achieve equivalent levels of performance with no statistically significant differences compared with matched controls. This information is unique when advising high-level athletes on athletic performance after ACL reconstruction, suggesting that those who fully recover and return to play appear to have no decrement in athletic performance.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Desempenho Atlético , Futebol Americano/lesões , Traumatismos do Joelho/cirurgia , Adulto , Estudos de Casos e Controles , Humanos , Masculino , Estudos Retrospectivos , Adulto Jovem
10.
J Miss State Med Assoc ; 55(4): 132, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24979942
11.
Zootaxa ; 3823: 1-84, 2014 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-24989879

RESUMO

The history of sponge collecting and systematics in British Columbia is reviewed over the period 1878 to 1966. Recent additions and changes are provided in an on-line species list: www.mareco/org/kml/projects/NEsponges.asp. Hadromerids are the focus of this paper as eight of 19 species in British Columbia are considered new. An additional new species is described from southern California to clarify the status of Tethya californiana in BC. An update is timely for hadromerids in BC as there is new material and renewed interest, while existing descriptions are often inadequate. We describe new species and provide additions to previous descriptions for sponges of the order Hadromerida (Porifera: Demospongiae) in the cold temperate NE Pacific off British Columbia and adjacent waters. We propose one range extension and one new species in Clionaidae; two range extensions and five new species in Polymastiidae; one range extension, two name changes and two new species in Suberitidae; and one new species in Tethyidae. New species include Pione gibraltarensis n.sp., Polymastia piscesae n. sp., Radiella endeavourensis n. sp., Sphaerotylus raphidophora n. sp., Sphaerotylus verenae n. sp., Weberella perlucida n. sp., Prosuberites saanichensis n. sp., Suberites lambei n. sp., and Tethya vacua n. sp..


Assuntos
Poríferos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Colúmbia Britânica , Ecossistema , Tamanho do Órgão , Poríferos/anatomia & histologia , Poríferos/crescimento & desenvolvimento
12.
Zootaxa ; 3786: 101-23, 2014 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-24869529

RESUMO

Interest in cladorhizid sponges has grown rapidly in the past 19 years since a unique feeding strategy, carnivory, was described by Vacelet and Boury-Esnault in 1995. Since that time, 31% of the 133 extant cladorhizids have been described. Previously, seven species of cladorhizid sponges were known from the Northeast Pacific. Here we describe four additional species, including two species of Asbestopluma and two species of Cladorhiza. We report on species ranges, habitat, and ecology, including one from a chemosynthetic environment that appears to be using methane-oxidizing bacteria as a nutrient source. In fact, three of the four species described here were found in chemosynthetic habitats. The presence of small crustacean prey was also documented for three of these species. 


Assuntos
Poríferos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Animais , Carnivoridade , Ecossistema , Oceano Pacífico , Poríferos/anatomia & histologia , Poríferos/fisiologia
13.
PLoS One ; 8(12): e83118, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24358253

RESUMO

Culturing experiments were performed on sediment samples from the Ythan Estuary, N. E. Scotland, to assess the impacts of ocean acidification on test surface ornamentation in the benthic foraminifer Haynesina germanica. Specimens were cultured for 36 weeks at either 380, 750 or 1000 ppm atmospheric CO2. Analysis of the test surface using SEM imaging reveals sensitivity of functionally important ornamentation associated with feeding to changing seawater CO2 levels. Specimens incubated at high CO2 levels displayed evidence of shell dissolution, a significant reduction and deformation of ornamentation. It is clear that these calcifying organisms are likely to be vulnerable to ocean acidification. A reduction in functionally important ornamentation could lead to a reduction in feeding efficiency with consequent impacts on this organism's survival and fitness.


Assuntos
Ácidos/farmacologia , Foraminíferos/citologia , Foraminíferos/efeitos dos fármacos , Água do Mar/química , Ácidos/análise , Animais , Dióxido de Carbono/química , Dióxido de Carbono/farmacologia , Relação Dose-Resposta a Droga , Ecossistema , Foraminíferos/crescimento & desenvolvimento , Foraminíferos/ultraestrutura , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Oceanos e Mares
14.
Zookeys ; (338): 11-28, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24146581

RESUMO

Two new species of Demospongiae are described for British Columbia and adjacent waters in the family Axinellidae, Auletta krautteri sp. n. and Dragmacidon kishinensis sp. n. They represent range extensions for both of these genera. Both are fairly commonly encountered, Auletta krautteri below diving depths (87 to at least 300 m) and Dragmacidon kishinensis in shallow water (intertidal to 30 m). We propose an amended genus diagnosis for Auletta to account for the variability among species in principal spicules that form the ascending tracts to be either oxeas, styles or strongyles rather than just oxeas.

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