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1.
J Vasc Surg ; 79(3): 569-576, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37923021

RESUMO

OBJECTIVE: The MANTA device is a plug-based vascular closure device (VCD) designed for large bore femoral arterial access site closure. It showed promising results in transcatheter aortic valve replacement cases. In this study, we report our results and evaluate the MANTA VCD in percutaneous endovascular aortic aneurysm repair (pEVAR). METHODS: All data of consecutive patients who underwent an elective pEVAR between October 2018 and December 2022 were retrospectively reviewed. In all patients at least one common femoral artery was intended to close with the MANTA VCD. Depending on the sheath size, the 14Fr or 18Fr MANTA VCD was used. On the preoperative computed tomography scan, the diameter of the common femoral artery (CFA) was measured and the amount of calcification based on the Peripheral Arterial Calcium Scoring System (PACSS) was scored. Primary outcome was procedural technical success. Procedural technical success was defined as placement of the MANTA closure device resulting in vascular closure with patent CFA, without requiring immediate open or endovascular surgery. The secondary outcomes were access site complications requiring reintervention and all-cause mortality at 30-day follow-up. RESULTS: In total, 152 consecutive patients underwent pEVAR with 291 common femoral artery closure procedures with the Manta VCD. Mean age was 74.1 ± 6.4 years, with a mean body mass index of 27.7 ± 4.4 kg/m2. The mean diameter of the CFA was 10.5 ± 1.9 mm. In 52.6% of the cases, there were no calcification on the preoperative computed tomography scan. The 18Fr and 14Fr Manta VCD were used 169 and 122 times, respectively. The technical success rate was 96.6%. Major vascular complications were reported in 4.5% of the cases, without any death-related events. CONCLUSIONS: This single-center retrospective cohort study analyzed the procedural technical success, major vascular complications and all-cause mortality at 30-day follow-up of the MANTA vascular closure device in 152 pEVAR patients with 291 common femoral artery closure procedures. The technical success rate was 96,6%. Major vascular complications were reported in 4.5% of the cases, without any death related events. We concluded that the MANTA device is a safe and feasible option with a high rate of technical success in patients undergoing pEVAR.


Assuntos
Aneurisma Aórtico , Procedimentos Endovasculares , Dispositivos de Oclusão Vascular , Humanos , Idoso , Idoso de 80 Anos ou mais , Procedimentos Endovasculares/efeitos adversos , Técnicas Hemostáticas , Estudos Retrospectivos , Resultado do Tratamento , Aneurisma Aórtico/diagnóstico por imagem , Aneurisma Aórtico/cirurgia , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/cirurgia
2.
Environ Res ; 244: 117914, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38141919

RESUMO

In the backdrop of carbon peaking and carbon neutrality, carbon emissions have always been a major concern. The approach of the heterogeneity grey model is proposed, aiming to predict carbon emissions of 30 provinces in China. This model combines the manta ray foraging optimization algorithm to search for the optimal heterogeneity coefficient. By using the heterogeneity grey model, the carbon emissions are analyzed in 30 provinces of China from 2022 to 2030 considering different environmental protection investment scenarios. The results indicate that in 19 provinces from 2022 to 2030, there is a significant decrease in carbon emissions as government investment increases. In 11 provinces during the same period, there is a rising trend in carbon emissions with the increase of government investment. Hence, achieving a reduction in carbon emissions necessitates not only relying on government investment in environmental protection but also exploring alternative approaches to mitigate carbon emissions. The methodologies and conclusions proposed in this study can provide technical references and making decision references for provincial carbon emission efforts.


Assuntos
Dióxido de Carbono , Carbono , Carbono/análise , Dióxido de Carbono/análise , Conservação dos Recursos Naturais , China , Investimentos em Saúde , Desenvolvimento Econômico
3.
Vascular ; : 17085381241256191, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38785381

RESUMO

BACKGROUND: Majority of EVAR procedures are performed with percutaneous arterial access, unless there is severe steno-occlusive disease in the common femoral arteries (CFA). We present our experience of using MANTA closure device with a retrospective evaluation of its safety and efficacy, in the elective setting, and in the emergent setting for ruptured aortic aneurysm. DESIGN AND METHODS: Between Feb 2021 and May 2023 a total of 75 EVAR procedures were closed with a Manta device. Data was collected prospectively and analysed retrospectively. In 75 patients, 128 CFAs were closed with a Manta closure device including 4 emergent ruptured aneurysms. RESULTS: 67 male and 8 female patients with a median age of 77 years had percutaneous EVAR using Manta as a closure device. 128 CFAs were closed with Manta closure device. 3% (4/128) had deployment failures, with three requiring surgical cut down and closure. In one patient, a second Manta device deployment achieved satisfactory haemostasis. Three deployments were complicated by pseudoaneurysms of the CFA, all requiring no further interventions/treatment. No death related to severe haemorrhage from device failure. The pre- and post-procedure CFA puncture site AP diameter was recorded in a total of 106 cases with appropriate follow-up. 66% of these (70/106) had no reduction in CFA diameter post Manta closure. 34% (36/106) had some reduction of vessel AP size CFA post EVAR. No adverse features or further treatment was required due to reduction of vessel diameter in these cases (ongoing yearly surveillance). CONCLUSIONS: Manta closure device is safe and easy to deploy with an overall success rate of 97%. There is a short learning curve. Ultrasound assessment and precise puncture at the healthy section of femoral artery are the key to achieve successful haemostasis with Manta closure device. Our findings suggest there is an association of non-clinically significant mild reduction in CFA vessel AP diameter post Manta closure device, which does not require further intervention.

4.
J Fish Biol ; 105(1): 34-45, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38622835

RESUMO

The blue shark Prionace glauca plays a critical role as a predator in marine ecosystems but is threatened by by-catch. To obtain more precise biological data, a Bayesian approach was used, and 536 vertebrae samples collected during 1 year at the landing stage called "Playita Mía" Manta, Ecuador, were analysed. The objective was to estimate the age and growth parameters of the species. The size of the specimens varied between 116 and 310 cm in total length (TL). Using a Bayesian approach based on the Markov Chain Monte Carlo (MCMC) method, growth parameters were evaluated. The von Bertalanffy model was the one that best fitted the data and provided more adequate estimates (females: L ∞ = 325.50 cm, L 0 = 53.23 cm, and k = 0.12 years; males: L ∞ = 331.47 cm, L 0 = 51.59 cm, k = 0.12 years -1; combined sexes: L ∞ = 329.65 cm, L 0 = 53.64 cm, k = 0.11 year-1). The results indicated that females and males have a similar growth, and that the species has a slow growth. Further studies using multi-model Bayesian approaches and covering a broader range of sizes in the Pacific Ocean are suggested. These studies will provide crucial information for the management and conservation of this species.


Assuntos
Teorema de Bayes , Tubarões , Animais , Tubarões/crescimento & desenvolvimento , Masculino , Feminino , Equador , Oceano Pacífico , Modelos Biológicos , Tamanho Corporal , Método de Monte Carlo
5.
Prep Biochem Biotechnol ; 54(2): 226-238, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37210635

RESUMO

Peptidases, which constitute about 20% of the global enzyme market, have found applications in detergent, food and pharmaceutical industries, and could be produced on a large scale using low-cost agro-industrial waste. An acidophilic Bacillus cereus strain produced acidic peptidase on binary-agro-industrial waste comprising yam peels and fish processing waste at pH 4.5 with high catalytic activity. A five-variable central composite rotatable design of a response surface methodology was used to model bioprocess conditions for improved peptidase production in solid-state fermentation. Data generated was leveraged as the basis for applying the novel Manta-ray foraging optimization-linked feed-forward artificial neural network to predict bioprocess conditions optimally. Results obtained from the optimization experiments revealed a significant coefficient of determination of 0.9885 with low-performance error. The bioprocess predicted a peptidase activity of 1035.32 U/mL under optimized conditions set as 54.8 g/100 g yam peels, 23.85 g/100 g fish waste, 0.31 g/100 g CaCl2, 47.54% (v/w) moisture content, and pH 2. Peptidase activity was improved 5-fold, and was stable for 240 min between pH 2.5 and 3.5. Michaelis-Menten kinetics revealed a Km of 0.119 mM and a catalytic efficiency of 45462.19 mM-1 min-1. The bioprocess holds promise for sustainable enzyme-driven applications.


Assuntos
Resíduos Industriais , Peptídeo Hidrolases , Fermentação , Bacillus cereus , Algoritmos
6.
Catheter Cardiovasc Interv ; 101(4): 817-827, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36802100

RESUMO

BACKGROUND: Studies comparing plug-based (i.e., MANTA) with suture-based (i.e., ProStar XL and ProGlide) vascular closure devices (VCDs) for large-bore access closure after transcatheter aortic valve replacement (TAVR) have yielded mixed results. AIMS: To examine the comparative safety and efficacy of both types of VCDs among TAVR recipients. METHODS: An electronic database search was performed through March 2022 for studies comparing access-site related vascular complications with plug-based versus suture-based VCDs for large-bore access site closure after transfemoral (TF) TAVR. RESULTS: Ten studies (2 randomized controlled trials [RCTs] and 8 observational studies) with 3113 patients (MANTA = 1358, ProGlide/ProStar XL = 1755) were included. There was no difference between plug-based and suture-based VCD in the incidence of access-site major vascular complications (3.1% vs. 3.3%, odds ratio [OR]: 0.89; 95% confidence interval [CI]: 0.52-1.53). The incidence of VCD failure was lower in plug-based VCD (5.2% vs. 7.1%, OR: 0.64; 95% CI: 0.44-0.91). There was a trend toward a higher incidence of unplanned vascular intervention in plug-based VCD (8.2% vs. 5.9%, OR: 1.35; 95% CI: 0.97-1.89). Length of stay was shorter with MANTA. Subgroup analyses suggested significant interaction based on study designs such that there was higher incidence of access-site vascular complications and bleeding events with plug-based versus suture-based VCD among RCTs. CONCLUSION: In patients undergoing TF-TAVR, large-bore access site closure with plug-based VCD was associated with a similar safety profile as suture-based VCD. However, subgroup analysis showed that plug-based VCD was associated with higher incidence of vascular and bleeding complications in RCTs.


Assuntos
Estenose da Valva Aórtica , Substituição da Valva Aórtica Transcateter , Dispositivos de Oclusão Vascular , Humanos , Resultado do Tratamento , Estenose da Valva Aórtica/cirurgia , Suturas , Artéria Femoral/cirurgia , Técnicas Hemostáticas , Valva Aórtica/cirurgia
7.
Pediatr Cardiol ; 44(7): 1623-1628, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37418147

RESUMO

VA-ECMO can be lifesaving in cardiogenic shock in children. While surgical vascular repair is the current standard of care for decannulation, it comes with notable risks. We present a series of eight patients who underwent decannulation with a collagen plug-based vascular closure device (MANTA) for the common femoral artery. Seven of the patients were successfully decannulated without access site-related vascular complications. One required conversion to surgical cut-down with arterial repair due to device failure. This series demonstrates the successful use of the MANTA device in percutaneous VA-ECMO decannulation in the pediatric population, while highlighting potential technical challenges for success.


Assuntos
Cateterismo Periférico , Oxigenação por Membrana Extracorpórea , Pediatria , Dispositivos de Oclusão Vascular , Humanos , Criança , Oxigenação por Membrana Extracorpórea/efeitos adversos , Cateterismo Periférico/efeitos adversos , Estudos Retrospectivos , Artéria Femoral/cirurgia , Resultado do Tratamento
8.
Catheter Cardiovasc Interv ; 99(6): 1945-1952, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35067004

RESUMO

BACKGROUND: There is limited experience of using the MANTA plug-based vascular closure device for percutaneous arterial closure of the femoral artery after venoarterial extracorporeal membrane oxygenation. OBJECTIVES: To study femoral artery complications and need for subsequent vascular interventions after percutaneous decannulation of venoarterial extracorporeal membrane oxygenation (VA ECMO) using the MANTA plug-based vascular closure device. METHODS: We studied 34 consecutive patients who underwent percutaneous decannulation of VA ECMO using the MANTA device. Primary outcomes were conversion to surgical cutdown of the groin at decannulation (immediate) or later. Secondary outcomes were type of vascular complication necessitating conversion to surgical cutdown of the groin. RESULTS: Six (17.7%) patients had to undergo immediate (n = 3) or late (n = 3) conversion to surgical cutdown of the groin. Of these, three were owing to occlusion of the common femoral artery resulting in insufficient distal perfusion and three owing to bleeding or pseudoaneurysm. The mechanism of failure was complete intravascular deployment of the MANTA device in three patients, incomplete MANTA sealing of the arteriotomy in one patient, MANTA-unrelated thrombotic occlusion in one patient, and unknown in one patient. Surgical cut-down was typically performed with concomitant catheter thrombectomy with or without patch reconstruction of the artery. CONCLUSION: Percutaneous decannulation of VA ECMO using the MANTA VCD was feasible but a substantial number of patients needed to be converted to unplanned surgical repair, owing to either closure site-located stenosis/occlusion or bleeding. If suboptimal MANTA positioning is suspected, a low threshold for conversion to surgical cutdown of the groin is recommended.


Assuntos
Cateterismo Periférico , Oxigenação por Membrana Extracorpórea , Dispositivos de Oclusão Vascular , Cateterismo Periférico/efeitos adversos , Cateterismo Periférico/métodos , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/cirurgia , Hemorragia/etiologia , Hemorragia/prevenção & controle , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Dispositivos de Oclusão Vascular/efeitos adversos
9.
Artif Organs ; 46(7): 1382-1388, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35132654

RESUMO

BACKGROUND: The use of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) decannulation with different percutaneous closure devices has been increasing. At our center, ProGlide devices have been used since November 2018, and Manta devices became an alternative since March 2020. This study aimed to compare the success and complication rates and the clinical outcomes of ProGlide and Manta devices for VA-ECMO decannulation after arteriotomy wound closure. METHODS: We retrospectively reviewed the results of bedside VA-ECMO decannulation between November 2018 and June 2021. Patients with VA-ECMO who could be bridged to recovery were recruited and divided into the ProGlide or Manta group based on the closure device used. Procedure time, amount of blood loss, amount of blood products transfused, and use of vasoactive medications during the procedure were documented. Clinical examination and Doppler ultrasound were performed to detect any complications. RESULTS: After the closure technique, ProGlide was used in 44 patients and Manta was used in 13. There was no significant difference in the success rate between the ProGlide and Manta groups (86.4% vs. 100%). Amount of blood loss was greater in the ProGlide group than in the Manta group (290 [100-400] ml vs. 50 [50-100] ml), and more patients in the ProGlide group required an increased dose of inotropes during the procedure (59.1% vs. 15.4%), but the transfusion requirement was similar between the two groups. CONCLUSIONS: The success rate of hemostasis using arteriotomy wound closure during VA-ECMO decannulation was similar between the two devices.


Assuntos
Oxigenação por Membrana Extracorpórea , Oxigenação por Membrana Extracorpórea/métodos , Artéria Femoral , Hemorragia/etiologia , Hong Kong , Humanos , Estudos Retrospectivos
10.
Environ Monit Assess ; 194(12): 851, 2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36201051

RESUMO

The use of citizen science in the collection of surface water marine microplastics (MP) samples with manta trawl was tested in the Baltic Sea, where the collection of surface water samples is often hampered by environmental conditions. Sampling was carried out at 7 locations around the Baltic Sea with a custom-made manta trawl which was operated onboard a sailing boat. The total concentrations of ≥ 0.3 mm MP in the samples ranged from 0.45 to 1.98 MP m-3. Based on the results and experiences from this study, citizen science could be introduced into the toolbox of monitoring large MP. When the common basic constraints of surface water sampling within a regional sea are defined and agreed upon, citizen science could be used for strengthening the power of assessments on the state of the marine environment by increasing the spatial coverage of the monitored area.


Assuntos
Ciência do Cidadão , Poluentes Químicos da Água , Monitoramento Ambiental/métodos , Microplásticos , Plásticos , Água , Poluentes Químicos da Água/análise
11.
Catheter Cardiovasc Interv ; 98(3): 586-587, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34498392

RESUMO

The MANTA is a new, easy-to-use, collagen plug-based vascular closure device specifically designed for large-bore arteriotomy closure. The authors report on their experience comparing the MANTA device with the Perclose ProGlide technique in patients undergoing transcatheter aortic valve replacement. They found similar rates of success and vascular complications with both devices, suggesting that MANTA is a suitable option for these patients. It remains to be determined whether one device will emerge as the ideal choice for most patients. Device cost is a significant barrier to widespread adoption, but price has decreased recently.


Assuntos
Cateterismo Periférico , Dispositivos de Oclusão Vascular , Cateterismo Periférico/efeitos adversos , Artéria Femoral , Técnicas Hemostáticas/efeitos adversos , Humanos , Resultado do Tratamento
12.
Catheter Cardiovasc Interv ; 97(2): 282-286, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-32272496

RESUMO

Successful closure of large bore vascular access (≥12 Fr) is facilitated by the MANTA vascular closure device; however, it requires a critical first step of measuring "skin to arterial wall" depth of the access site using the depth locator before dilating the vessel above 8 Fr. It may be challenging at times to acquire the deployment depth at the onset of the procedure due to case urgency, delayed closure, or when large bore access is obtained at a different institution. We discuss a novel technique of measuring the deployment depth and successful delayed closure of large bore arterial access using the MANTA closure device.


Assuntos
Cateterismo Periférico , Dispositivos de Oclusão Vascular , Artéria Femoral , Técnicas Hemostáticas , Humanos , Resultado do Tratamento
13.
Perfusion ; 36(2): 118-121, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32571179

RESUMO

Percutaneous closure of arteriotomy wound during peripheral venoarterial extracorporeal membrane oxygenation decannulation was shown to be safe and allow earlier mobilization. The new MantaTM vascular closure device (Essential Medical), designed for the closure of arterotomy wound created by large-bore vascular sheaths up to 25Fr during endovascular catheterization procedures, was reported to be applicable in venoarterial extracorporeal membrane oxygenation decannulation. In this article, we would like to share our experience of using real-time ultrasound guidance to ensure the safe application of Manta during bedside venoarterial extracorporeal membrane oxygenation decannulation.


Assuntos
Oxigenação por Membrana Extracorpórea , Dispositivos de Oclusão Vascular , Cateterismo , Humanos , Estudos Retrospectivos , Ultrassonografia , Ultrassonografia de Intervenção
14.
J Environ Manage ; 298: 113520, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34391109

RESUMO

An innovative predictive model was employed to predict the key performance indicators of a full-scale wastewater treatment plant (WWTP) operated with an activated sludge treatment process. The data-driven model was obtained using data gathered from Cairo, Egypt. The proposed model consists of Random Vector Functional Link (RVFL) Networks incorporated with Manta Ray Foraging Optimizer (MRFO). RVFL is used as an advanced Artificial Neural Network (ANN) that avoids the common conventional ANN problems such as overfitting. MRFO is employed to determine the best RVFL parameters to maximize the prediction accuracy of the model. The developed MRFO-RVFL is compared with conventional RVFL to figure out the role of MRFO as an optimization tool to enhance model performance. Both models were trained and tested using experimental data measured during a long period of 222 days. This study aims to provide an accurate prediction of the most widely treated effluent indicators of BOD5 and TSS in the wastewater treatment plants. In this study, ten well-known influent wastewater parameters, BOD5, TSS, and VSS, influent flow rate, pH, ambient temperature, F/M ratio, SRT, WAS, and RAS, the output BOD5 and TSS were modeled and predicted using the integrated MRFO-RVFL algorithms and compared with the standalone RVFL model. The performance of the models was evaluated using different assessment measures such as R2, RMSE, and others. The obtained results of R2 and RMSE for the MRFO-RVFL model were 0.924 and 3.528 for BOD5 and 0.917 and 6.153 for TSS, which were much better than the results of conventional RVFL with 0.840 and 6.207 for BOD5 and 0.717 and 10.05 for TSS. Based on the obtained results, the selective model (MRFO-RVFL) exhibited a higher performance and validity to predict the TSS and optimal BOD5.


Assuntos
Esgotos , Purificação da Água , Algoritmos , Redes Neurais de Computação , Eliminação de Resíduos Líquidos , Águas Residuárias
15.
J Card Surg ; 35(11): 3148-3149, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32939801

RESUMO

BACKGROUND: We present a complication following the deployment of the MANTA vascular closure device (VCD) following a transcatheter aortic valve replacement procedure which resulted in occlusion of the common femoral artery. AIMS: To address possible complications associated with MANTA VCD. RESULTS: This was addressed by ballooning the site from the contralateral side which re-established flow. CONCLUSION: We believe this is the first report to address this kind of complication and may prove useful as more of the MANTA devices are being used in multiple procedures.


Assuntos
Estenose da Valva Aórtica/cirurgia , Arteriopatias Oclusivas/etiologia , Artéria Femoral , Complicações Pós-Operatórias/etiologia , Substituição da Valva Aórtica Transcateter , Dispositivos de Oclusão Vascular/efeitos adversos , Arteriopatias Oclusivas/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico por imagem , Índice de Gravidade de Doença
16.
J Fish Biol ; 96(3): 835-840, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31925780

RESUMO

The known distribution of manta rays in Australian waters is patchy, with records primarily centred around tourism hotspots. We collated 11,614 records of Mobula alfredi from photo-ID databases (n = 10,715), aerial surveys (n = 378) and online reports (n = 521). The study confirms an uninterrupted coastal distribution from north of 26°S and 31°S on the west and east coasts, respectively. More southerly M. alfredi records relate to warm-water events with a southernmost extent at 34°S. Coastal sightings of Mobula birostris were rare (n = 32), likely reflecting a preference for offshore waters, but encompass a wider latitudinal extent than M. alfredi of 10-40°S.


Assuntos
Distribuição Animal , Elasmobrânquios/fisiologia , Animais , Austrália , Oceanos e Mares
17.
Proc Biol Sci ; 286(1912): 20191879, 2019 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-31594509

RESUMO

Intraspecific colour polymorphisms have been the focus of numerous studies, yet processes affecting melanism in the marine environment remain poorly understood. Arguably, the most prominent example of melanism in marine species occurs in manta rays (Mobula birostris and Mobula alfredi). Here, we use long-term photo identification catalogues to document the frequency variation of melanism across Indo-Pacific manta ray populations and test for evidence of selection by predation acting on colour morph variants. We use mark-recapture modelling to compare survivorship of typical and melanistic colour morphs in three M. alfredi populations and assess the relationship between frequency variation and geographical distance. While there were large differences in melanism frequencies among populations of both species (0-40.70%), apparent survival estimates revealed no difference in survivorship between colour morphs. We found a significant association between phenotypic and geographical distance in M. birostris, but not in M. alfredi. Our results suggest that melanism is not under selection by predation in the tested M. alfredi populations, and that frequency differences across populations of both species are a consequence of neutral genetic processes. As genetic colour polymorphisms are often subjected to complex selection mechanisms, our findings only begin to elucidate the underlying evolutionary processes responsible for the maintenance and frequency variation of melanism in manta ray populations.


Assuntos
Pigmentação/genética , Polimorfismo Genético/fisiologia , Rajidae/genética , Animais , Cor
18.
J Zoo Wildl Med ; 47(3): 927-930, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27691938

RESUMO

An adult, female, reef manta ray (Manta alfredi) was evaluated for abnormal swimming and coelomic distention after colliding with a floating dock in an exhibit. Initial clinical signs included abnormal posture and swimming. Clinical signs progressed to include muscle wasting, poor body condition, and coelomic distention. Further diagnostics revealed excessive exhibit substrate within the gastrointestinal tract, gastric ulcers, free coelomic fluid, possible spinal lesion, possible uterine abnormality, and hematologic changes. The ray was treated with repeated gastroscopic examinations to remove substrate from the stomach. Psyllium and mineral oil were administered in gel food to assist with passage of substrate through the gastrointestinal tract. Gastric ulcers were treated with sucralfate. Vitamin B complex, iron dextran, and Yunnan Paiyao were used to treat the anemia. Amikacin and sulfadimethoxine-ormetoprim were administered for suspected bacterial and coccidial infections, respectively. Over the course of 11 mo the ray returned to normal health.


Assuntos
Elasmobrânquios/sangue , Doenças dos Peixes/terapia , Animais , Antiulcerosos/uso terapêutico , Líquidos Corporais , Comportamento Alimentar , Feminino , Traumatismos da Coluna Vertebral/complicações , Traumatismos da Coluna Vertebral/veterinária , Úlcera Gástrica/diagnóstico , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/patologia , Sucralfato/uso terapêutico , Natação , Ferimentos e Lesões
19.
Mol Phylogenet Evol ; 83: 72-85, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25462995

RESUMO

Manta and devil rays are an iconic group of globally distributed pelagic filter feeders, yet their evolutionary history remains enigmatic. We employed next generation sequencing of mitogenomes for nine of the 11 recognized species and two outgroups; as well as additional Sanger sequencing of two mitochondrial and two nuclear genes in an extended taxon sampling set. Analysis of the mitogenome coding regions in a Maximum Likelihood and Bayesian framework provided a well-resolved phylogeny. The deepest divergences distinguished three clades with high support, one containing Manta birostris, Manta alfredi, Mobula tarapacana, Mobula japanica and Mobula mobular; one containing Mobula kuhlii, Mobula eregoodootenkee and Mobula thurstoni; and one containing Mobula munkiana, Mobula hypostoma and Mobula rochebrunei. Mobula remains paraphyletic with the inclusion of Manta, a result that is in agreement with previous studies based on molecular and morphological data. A fossil-calibrated Bayesian random local clock analysis suggests that mobulids diverged from Rhinoptera around 30 Mya. Subsequent divergences are characterized by long internodes followed by short bursts of speciation extending from an initial episode of divergence in the Early and Middle Miocene (19-17 Mya) to a second episode during the Pliocene and Pleistocene (3.6 Mya - recent). Estimates of divergence dates overlap significantly with periods of global warming, during which upwelling intensity - and related high primary productivity in upwelling regions - decreased markedly. These periods are hypothesized to have led to fragmentation and isolation of feeding regions leading to possible regional extinctions, as well as the promotion of allopatric speciation. The closely shared evolutionary history of mobulids in combination with ongoing threats from fisheries and climate change effects on upwelling and food supply, reinforces the case for greater protection of this charismatic family of pelagic filter feeders.


Assuntos
Evolução Biológica , Filogenia , Rajidae/classificação , Animais , Teorema de Bayes , Núcleo Celular/genética , Fósseis , Genoma Mitocondrial , Sequenciamento de Nucleotídeos em Larga Escala , Funções Verossimilhança , Modelos Genéticos , Alinhamento de Sequência , Análise de Sequência de DNA
20.
Bioinspir Biomim ; 19(2)2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38176107

RESUMO

This study investigates the interaction of a two-manta-ray school using computational fluid dynamics simulations. The baseline case consists of two in-phase undulating three-dimensional manta models arranged in a stacked configuration. Various vertical stacked and streamwise staggered configurations are studied by altering the locations of the top manta in the upstream and downstream directions. Additionally, phase differences between the two mantas are considered. Simulations are conducted using an in-house developed incompressible flow solver with an immersed boundary method. The results reveal that the follower will significantly benefit from the upstroke vortices (UVs) and downstroke vortices depending on its streamwise separation. We find that placing the top manta 0.5 body length (BL) downstream of the bottom manta optimizes its utilization of UVs from the bottom manta, facilitating the formation of leading-edge vortices (LEVs) on the top manta's pectoral fins during the downstroke. This LEV strengthening mechanism, in turn, generates a forward suction force on the follower that results in a 72% higher cycle-averaged thrust than a solitary swimmer. This benefit harvested from UVs can be further improved by adjusting the phase of the top follower. By applying a phase difference ofπ/3to the top manta, the follower not only benefits from the UVs of the bottom manta but also leverages the auxiliary vortices during the upstroke, leading to stronger tip vortices and a more pronounced forward suction force. The newfound interaction observed in schooling studies offers significant insights that can aid in the development of robot formations inspired by manta rays.


Assuntos
Hidrodinâmica , Natação , Fenômenos Biomecânicos
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