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Ceramic membranes have been widely used in oil-water treatment; however, membrane fouling remains a challenge that must be addressed to improve the process feasibility. A thin layer of polydopamine (PDA) was dynamically deposited on the surface of the alumina hollow fiber membranes to reduce oil adhesion. The PDA-alumina membranes were characterized by using SEM-EDS, AFM, and water contact angle measurements. The performance of the modified membranes was evaluated using synthetic crude oil emulsions (100 mg·L-1) in a crossflow system. Membranes modified with PDA exhibited 97% oil rejection, and a stabilized permeate flux of 463 L·h-1·m-2 with a relative flux reduction of 60% and a flux recovery ratio of 75% was observed after cleaning, indicating lower oil adhesion and better fouling reversibility. The most predominant fouling mechanism for the modified membranes seems to be cake filtration because of the reduction in pore size due to the deposition of the PDA layer.
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Small-scale turbulent mixing drives the upwelling of deep water masses in the abyssal ocean as part of the global overturning circulation1. However, the processes leading to mixing and the pathways through which this upwelling occurs remain insufficiently understood. Recent observational and theoretical work2-5 has suggested that deep-water upwelling may occur along the ocean's sloping seafloor; however, evidence has, so far, been indirect. Here we show vigorous near-bottom upwelling across isopycnals at a rate of the order of 100 metres per day, coupled with adiabatic exchange of near-boundary and interior fluid. These observations were made using a dye released close to the seafloor within a sloping submarine canyon, and they provide direct evidence of strong, bottom-focused diapycnal upwelling in the deep ocean. This supports previous suggestions that mixing at topographic features, such as canyons, leads to globally significant upwelling3,6-8. The upwelling rates observed were approximately 10,000 times higher than the global average value required for approximately 30 × 106 m3 s-1 of net upwelling globally9.
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INTRODUCTION: Despite advancements in the treatment of benign prostatic hyperplasia (BPH), the mechanisms underlying BPH development and progression remain elusive and lacks a one-size-fits-all therapeutic solution. Prostatic inflammation contributes to BPH and lower urinary tract symptoms (LUTS), but the initial trigger remains unknown. Current research suggests dysbiosis of the urinary microbiome as a potential culprit. This systematic review explores the emerging field of the male urinary and prostatic microbiome and its relationship with BPH/LUTS. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. A systematic search in the Pubmed and Scopus databases was performed using specific terms. Inclusion criteria considered male non-neurogenic patients with LUTS due to BPH with analyses of urinary microbiome, concerning evaluation of English-language publications with relevance. RESULTS: Among seven articles involving 542 patients, there was an association between male LUTS/BPH and the urinary microbiome. Findings indicate a correlation between urinary microbiome dysbiosis and LUTS severity, with specific bacterial genera such as Streptococcus and Haemophilus linked to higher International Prostate Symptom Score (IPSS) scores and PSA levels. The fecal microbiome may be associated with LUTS, although contradictory findings are reported. The review also highlights methodological inconsistencies, small sample sizes, few negative controls and a lack of comprehensive clinical data as major limitations. CONCLUSIONS: While there is an undeniable correlation between the microbiome and LUTS/BPH, future research should aim to standardize sampling techniques and expand the score to include functional microbiome characterization, potentially leading to novel, microbiome-targeted therapeutic strategies for BPH.
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Turbulent mixing in the ocean exerts an important control on the rate and structure of the overturning circulation. However, the balance of processes underpinning this mixing is subject to significant uncertainties, limiting our understanding of the overturning's deep upwelling limb. Here, we investigate the hitherto primarily neglected role of tens of thousands of seamounts in sustaining deep-ocean upwelling. Dynamical theory indicates that seamounts may stir and mix deep waters by generating lee waves and topographic wake vortices. At low latitudes, stirring and mixing are predicted to be enhanced by a layered vortex regime in the wakes. Using three realistic regional simulations spanning equatorial to middle latitudes, we show that layered wake vortices and elevated mixing are widespread around seamounts. We identify scalings that relate mixing rate within seamount wakes to topographic and hydrographic parameters. We then apply such scalings to a global seamount dataset and an ocean climatology to show that seamount-generated mixing makes an important contribution to the upwelling of deep waters. Our work thus brings seamounts to the fore of the deep-ocean mixing problem and urges observational, theoretical, and modeling efforts toward incorporating the seamounts' mixing effects in conceptual and numerical ocean circulation models.
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Open-ocean polynyas formed over the Maud Rise, in the Weddell Sea, during the winters of 2016-2017. Such polynyas are rare events in the Southern Ocean and are associated with deep convection, affecting regional carbon and heat budgets. Using an ocean state estimate, we found that during 2017, early sea ice melting occurred in response to enhanced vertical mixing of heat, which was accompanied by mixing of salt. The melting sea ice compensated for the vertically mixed salt, resulting in a net buoyancy gain. An additional salt input was then necessary to destabilize the upper ocean. This came from a hitherto unexplored polynya-formation mechanism: an Ekman transport of salt across a jet girdling the northern flank of the Maud Rise. Such transport was driven by intensified eastward surface stresses during 2015-2018. Our results illustrate how highly localized interactions between wind, ocean flow and topography can trigger polynya formation in the open Southern Ocean.
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INTRODUÇÃO: A válvula aórtica bicúspide (BAV) ocorre em até 6% dos pacientes com estenose aórtica importante. Sua presença pode refletir um desafio para TAVI uma vez que pacientes com BAV podem possuir maiores diâmetros do anel valvar, calcificação acentuada dos folhetos e dilatação da aorta ascendente. O número crescente de TAVI nessa população torna imperativo um aprofundamento na investigação de seus resultados e desfechos clínicos. MÉTODOS: Retrospectivo, unicêntrico e observacional. Realizamos uma revisão de banco de dados e selecionamos pacientes submetidos a TAVI no período de novembro de 2020 a janeiro de 2024. O objetivo deste estudo é avaliar a incidência e resultados imediatos na população com BAV comparativamente aos pacientes com valva tricúspide. Para isso, foram coletados dados clínicos e demográficos, bem como informações sobre complicações e desfechos intrahospitalares após TAVI em ambas as populações, segundo o VARC 3. A análise dos dados foi realizada utilizando estatística descritiva e comparativa (Teste T de Student), com intuito de verificar se há diferenças significativas em desfechos entre as populações. RESULTADOS: De um total de 174 pacientes, 33 deles apresentaram BAV, resultando em uma incidência de 18,96%. A análise estatística não evidenciou diferença significativa nos dados de base de ambas as populações. Média de idade entre o grupo BAV (75,84 ± 8,19 anos) e o grupo tricúspide (78,61 ± 6,32 anos), com um p-valor não significativo de p 0,243. O STS score médio foi de 3,14 ± 1,86% no grupo BAV e 3,47 ± 1,97% no grupo tricúspide; p 0,12. Em relação ao procedimento, houve diferença significativa na necessidade de pré-dilatação entre os grupos, sendo necessária em 25 dos 33 casos de bicúspide (75,75%) e 71 dos 141 casos de tricúspide (50,35%) (p 0,008). Porém, não foi evidenciada diferença significativa no gradiente ventrículo esquerdo e aorta pós-procedimento de 4,53 ± 3,04 vs 5,33 ± 4,46; p 0,233, de bicúspide e tricúspide respectivamente; nem no tempo de permanência hospitalar pós procedimento 2,63 ± 2,11 vs 3,03 ± 4,29; p 0,439. Não foi observado também diferença significativa em relação a necessidade de marcapasso definitivo, refluxo paravalvular ou complicações hemorrágicas e vasculares. CONCLUSÃO: Com base nos resultados, não foi observada diferença significativa nos desfechos entre os pacientes com BAV e tricúspide. Estes achados sugerem que a TAVI é um tratamento seguro e eficaz para pacientes com BAV. No entanto, são necessários estudos adicionais com amostras mais amplas para confirmar esses resultados.
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Humanos , Idoso , Idoso de 80 Anos ou mais , Substituição da Valva Aórtica TranscateterRESUMO
Vaccine adjuvants increase the breadth of serum antibody responses, but whether this is due to the generation of antigen-specific B cell clones with distinct specificities or the maturation of memory B cell clones that produce broadly cross-reactive antibodies is unknown. Here, we longitudinally analyzed immune responses in healthy adults after two-dose vaccination with either a virus-like particle COVID-19 vaccine (CoVLP), CoVLP adjuvanted with AS03 (CoVLP+AS03), or a messenger RNA vaccination (mRNA-1273). CoVLP+AS03 enhanced the magnitude and durability of circulating antibodies and antigen-specific CD4+ T cell and memory B cell responses. Antigen-specific CD4+ T cells in the CoVLP+AS03 group at day 42 correlated with antigen-specific memory B cells at 6 months. CoVLP+AS03 induced memory B cell responses, which accumulated somatic hypermutations over 6 months, resulting in enhanced neutralization breadth of monoclonal antibodies. Furthermore, the fraction of broadly neutralizing antibodies encoded by memory B cells increased between day 42 and 6 months. These results indicate that AS03 enhances the antigenic breadth of B cell memory at the clonal level and induces progressive maturation of the B cell response.
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COVID-19 , Vacinas contra Influenza , Influenza Humana , Polissorbatos , Esqualeno , alfa-Tocoferol , Adulto , Humanos , Células B de Memória , Vacinas contra COVID-19 , Anticorpos Antivirais , COVID-19/prevenção & controle , Combinação de MedicamentosRESUMO
It is essential to evaluate the effects of operating conditions in submerged cultures of filamentous microorganisms. In particular, the impeller type influences the flow pattern, power consumption, and energy dissipation, leading to differences in the hydrodynamic environment that affect the morphology of the microorganism. This work investigated the effect of different impeller types, namely the Rushton turbine (RT-RT) and Elephant Ear impellers in up-pumping (EEUP) and down-pumping (EEDP) modes, on cellular morphology and clavulanic acid (CA) production by Streptomyces clavuligerus in a stirred-tank bioreactor. At 800 rpm and 0.5 vvm, the cultivations performed using RT-RT and EEUP impellers provided higher shear conditions and oxygen transfer rates than those observed with EEDP. These conditions resulted in higher clavulanic acid production using RT-RT (380.7 mg/L) and EEUP (453.3 mg/L) impellers, compared to EEDP (196.6 mg/L). Although the maximum CA concentration exhibited the same order of magnitude for RT-RT and EEUP impellers, the latter presented 40% of the specific power consumption (4.9 kW/m3) compared to the classical RT-RT (12.0 kW/m3). The specific energy for CA production ( E CA ), defined as the energy cost to produce 1 mg of CA, was 3.5 times lower using the EEUP impeller (1.91 kJ/mgCA) when compared to RT-RT (5.91 kJ/mgCA). Besides, the specific energy for O2 transfer ( E O 2 ), the energy required to transfer 1 mmol of O2, was 2.3 times lower comparing the EEUP impeller (3.28 kJ/mmolO2) to RT-RT (7.65 kJ/mmolO2). The results demonstrated the importance of choosing the most suitable impeller configuration in conventional bioreactors to manufacture bioproducts.
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Reatores Biológicos , Ácido Clavulânico , Streptomyces , Ácido Clavulânico/biossíntese , Streptomyces/metabolismo , Streptomyces/crescimento & desenvolvimento , Reatores Biológicos/microbiologia , Fermentação , Antibacterianos/biossínteseRESUMO
Elevated ice shelf melt rates in West Antarctica have been attributed to transport of warm Circumpolar Deep Water (CDW) onto the continental shelf via bathymetric troughs. These inflows are supplied by an eastward, subsurface slope current (referred to as the Antarctic Slope Undercurrent) that opposes the westward momentum input from local winds and tides. Despite its importance to basal melt, the mechanism via which the undercurrent forms, and thus what controls the shoreward heat transport, remains unclear. In this study, the dynamics of the undercurrent are investigated using high-resolution process-oriented simulations with coupled ocean, sea ice, and ice shelf components. It is shown that the bathymetric steering of the undercurrent toward the ice shelf is driven by upwelling of meltwater within the ice shelf cavity. Increased basal melt therefore strengthens the undercurrent and enhances onshore CDW transport, which indicates a positive feedback that may accelerate future melt of ice shelves, potentially further destabilizing the West Antarctic Ice Sheet.
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A gastrostomy is a common procedure for patients with swallowing problems or inability to maintain regular oral nutrition. These gastrostomy tubes need special attention, as complications can occur if the tubes are left unattended. In rare scenarios, these tubes can migrate and cause severe life-threatening difficulties such as bowel obstruction and pancreatitis. We present the case of a 76-year-old quadriplegic woman who had a gastrostomy tube. Suddenly, the tube was missing, and after urgent medical care, the gastrostomy tube was found within her bowel. After successful surgery, she recovered from this incident.
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Arterial hypertension (AH) is a multifactorial and asymptomatic disease that affects vital organs such as the kidneys and heart. Considering its prevalence and the associated severe health repercussions, hypertension has become a disease of great relevance for public health across the globe. Conventionally, the classification of an individual as hypertensive or non-hypertensive is conducted through ambulatory blood pressure monitoring over a 24-h period. Although this method provides a reliable diagnosis, it has notable limitations, such as additional costs, intolerance experienced by some patients, and interferences derived from physical activities. Moreover, some patients with significant renal impairment may not present proteinuria. Accordingly, alternative methodologies are applied for the classification of individuals as hypertensive or non-hypertensive, such as the detection of metabolites in urine samples through liquid chromatography or mass spectrometry. However, the high cost of these techniques limits their applicability for clinical use. Consequently, an alternative methodology was developed for the detection of molecular patterns in urine collected from hypertension patients. This study generated a direct discrimination model for hypertensive and non-hypertensive individuals through the amplification of Raman signals in urine samples based on gold nanoparticles and supported by chemometric techniques such as partial least squares-discriminant analysis (PLS-DA). Specifically, 162 patient urine samples were used to create a PLS-DA model. These samples included 87 urine samples from patients diagnosed with hypertension and 75 samples from non-hypertensive volunteers. In the AH group, 35 patients were diagnosed with kidney damage and were further classified into a subgroup termed (RAH). The PLS-DA model with 4 latent variables (LV) was used to classify the hypertensive patients with external validation prediction (P) sensitivity of 86.4%, P specificity of 77.8%, and P accuracy of 82.5%. This study demonstrates the ability of surface-enhanced Raman spectroscopy to differentiate between hypertensive and non-hypertensive patients through urine samples, representing a significant advance in the detection and management of AH. Additionally, the same model was then used to discriminate only patients diagnosed with renal damage and controls with a P sensitivity of 100%, P specificity of 77.8%, and P accuracy of 82.5%.
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Hipertensão , Nefropatias , Nanopartículas Metálicas , Humanos , Análise Espectral Raman/métodos , Ouro , Monitorização Ambulatorial da Pressão Arterial , Nanopartículas Metálicas/química , Nefropatias/diagnóstico , Urinálise/métodos , Hipertensão/urinaRESUMO
OBJECTIVES: To quantitatively describe the nature, severity, and duration of symptoms and functional impairment during recovery from transurethral resection of bladder tumors. MATERIALS AND METHODS: All patients scheduled for transurethral resection were approached for enrollment in a text-message based ecological momentary symptom assessment platform. Nine patients reported outcomes were measured 7 days before surgery and on postoperative days 1, 2, 3, 5, 7, 10, and 14 using a 5-point Likert scale. Self-reported degree of hematuria was collected using a visual scale. Clinical data was collected via retrospective chart review. RESULTS: A total of 159 patients were analyzed. Postoperative symptoms were overall mild, with the largest differences from baseline to postoperative day 1 seen in dysuria (median 0/5 vs. 3/5) and ability to work (median 5/5 vs. 4/5). Recovery was generally rapid, with 76% of patients reporting ≥4/5 agreement with the statement "I feel recovered from surgery" by postoperative day 2, although 15% of patients reported persistently lower levels of agreement on postoperative day 10 or 14. Patients undergoing larger resections (≥2cm) did take longer to return to baseline in multiple symptom domains, but the difference of medians vs. those undergoing smaller resections was less than 1 day across all domains. Multivariable analysis suggested that receiving perioperative intravesical chemotherapy was associated with longer time to recovery. 84% of patients reported clear yellow urine by postoperative day 3. CONCLUSION: In this population, hematuria and negative effects on quality of life resulting from transurethral resection of bladder tumors were generally mild and short-lived, although a small number of patients experienced longer recoveries.
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Ressecção Transuretral da Próstata , Neoplasias da Bexiga Urinária , Humanos , Masculino , Ressecção Transuretral de Bexiga , Hematúria , Estudos Retrospectivos , Qualidade de Vida , Avaliação de Sintomas , Neoplasias da Bexiga Urinária/patologia , Ressecção Transuretral da Próstata/métodosRESUMO
OBJECTIVE: To evaluate perioperative and oncologic outcomes of a cohort of clinically node negative high-risk penile cancer patients undergoing robotic assisted inguinal lymph node dissection (RAIL) compared to patients undergoing open superficial inguinal lymph node dissection (OSILND). PATIENTS AND METHODS: We retrospectively reviewed the clinical characteristics and outcomes of clinically node negative high-risk penile cancer patients undergoing RAIL at MDACC from 2013-2019. We sought to compare this to a contemporary open cohort of clinically node negative patients treated from 1999 to 2019 at MDACC and Moffit Cancer Center (MCC) with an OSILND. Descriptive statistics were used to characterize the study cohorts. Comparison analysis between operative variables was performed using Fisher's exact test and Wilcoxon's rank-sum test. The Kaplan-Meier method was used to estimate survival endpoints. RESULTS: There were 24 patients in the RAIL cohort, and 35 in the OSILND cohort. Among the surgical variables, operative time (348.5 minutes vs. 239.0 minutes, P < 0.01) and the duration of operative drain (37 vs. 22 days Pâ¯=â¯0.017) were both significantly longer in the RAIL cohort. Complication incidences were similar for both cohorts (34.3% for OSILND vs. 33.3% for RAIL), with wound complications making up 33% of all complications for RAIL and 31% of complications for OSILND. No inguinal recurrences were noted in either cohort. The median follow-up was 40 months for RAIL and 33 months for OSILND. CONCLUSIONS: We observed similar complication rates and surgical variable outcomes in our analysis apart from operative time and operative drain duration. Oncological outcomes were similar between the two cohorts. RAIL was a reliable staging and potentially therapeutic procedure among clinically node negative patients with penile squamous cell carcinoma with comparable outcomes to an OSILND cohort.
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Neoplasias Penianas , Procedimentos Cirúrgicos Robóticos , Masculino , Humanos , Neoplasias Penianas/cirurgia , Neoplasias Penianas/patologia , Estudos Retrospectivos , Canal Inguinal/cirurgia , Canal Inguinal/patologia , Excisão de Linfonodo/métodos , Linfonodos/cirurgia , Linfonodos/patologia , Estadiamento de NeoplasiasAssuntos
Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Procedimentos Cirúrgicos Robóticos , Substituição da Valva Aórtica Transcateter , Humanos , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Resultado do Tratamento , Estudos Multicêntricos como AssuntoRESUMO
The natural products (NPs) biosynthetic gene clusters (BGCs) represent the adapting biochemical toolkit for microorganisms to thrive different microenvironments. Despite their high diversity, particularly at the genomic level, detecting them in a shake-flask is challenging and remains the primary obstacle limiting our access to valuable chemicals. Studying the molecular mechanisms that regulate BGC expression is crucial to design of artificial conditions that derive on their expression. Here, we propose a phylogenetic analysis of regulatory elements linked to biosynthesis gene clusters, to classify BGCs to regulatory mechanisms based on protein domain information. We utilized Hidden Markov Models from the Pfam database to retrieve regulatory elements, such as histidine kinases and transcription factors, from BGCs in the MIBiG database, focusing on actinobacterial strains from three distinct environments: oligotrophic basins, rainforests, and marine environments. Despite the environmental variations, our isolated microorganisms share similar regulatory mechanisms, suggesting the potential to activate new BGCs using activators known to affect previously characterized BGCs.
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MAIN CONCLUSION: After bud burst, a transcriptional reprogramming of the shikimate and phenylpropanoid pathways occurs in grapevine canes resulting in the accumulation of stilbenoids like resveratrol and viniferin. Stilbenoids are phenylpropanoid compounds with important biological properties and biotechnological applications that are synthesized in grapevine in response to different stresses. Although they are found in woody tissues, such as canes and buds, their biosynthesis and accumulation have been essentially described in berries. We have previously shown that transcripts encoding secondary metabolism enzymes accumulate in grapevine canes following the transition from dormancy (E-L 1) to bud burst (E-L 4) suggesting that secondary metabolites may accumulate in grapevine canes during this transition. In the present study, using UPLC-MS we demonstrate the accumulation of important metabolites such as ferulic acid and the stilbenoids E-resveratrol, E-piceatannol and E-ε-viniferin. Stilbenoids accumulation correlated with the increased expression of several stilbene synthase genes and of VviMYB14, encoding a transcription factor that regulates stilbene biosynthesis. In addition, a general stimulation of the plastidial shikimate pathway was observed. Taken together, results show that important secondary metabolites accumulate in the woody canes during bud burst. These findings may aid biotechnological approaches aimed at extracting biologically active phenolic compounds, including stilbenoids, from grapevine woody tissues.
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Espectrometria de Massas em Tandem , Madeira , Cromatografia Líquida , ResveratrolRESUMO
RFX, a rifamycin-based antibacterial agent obtained by the culture of the actinomycete Streptomyces mediterranei, has a broad antibacterial spectrum covering gram- positive, gram-negative, aerobic, and anaerobic bacteria. RFX is an antibiotic that elicits its effect by inhibiting bacterial RNA synthesis. When administered orally, its intestinal absorption is extremely low (<0.4%), restricting antibacterial activity mainly in the intestinal tract, with few systemic side effects. RFX has been recommended by the American Association for the Study of Liver Diseases and the European Association for the Study of the Liver guidelines for the treatment of HE. RFX may contribute to restore hepatic function and to decrease the development of liver fibrosis. Its efficacy has been shown in patients with previous hepatic encephalopathy and several complications, such as infections, including spontaneous bacterial peritonitis, ascites and oesophageal variceal bleeding. Thus, RFX has an outstanding role in the therapeutic arsenal in hepatic cirrhosis, under the concept of disease modifier.
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We report the synthesis, crystal structure, and characterisation of a dinuclear Co(II) compound with thiodiacetate (tda) and phenanthroline (phen) as ligands (1), and of a series of metal complexes isomorphous to 1 with different Co : Zn ratios (2, 4 : 1; 3, 1 : 1; 4, 1 : 4; 5, 1 : 10). General characterisation methodologies and X-ray data showed that all the synthesised complexes are isomorphous to Zn(II) and Cu(II) analogues (CSD codes: DUHXEL and BEBQII). 1 consists of centrosymmetric Co(II) ion dimers in which the ions are 3.214 Å apart, linked by two µ-O bridges. Each cobalt atom is in a distorted octahedral environment of the N2O3S type. UV-vis spectra of 1 and 5 are in line with high spin (S = 3/2) Co(II) ions in octahedral coordination and indicate that the electronic structure of both Co(II) ions in the dinuclear unit does not significantly change relative to that of the magnetically isolated Co(II) ion. EPR spectra of powder samples of 5 (Co : Zn ratio of 1 : 10) together with spectral simulation indicated high spin Co(II) ions with high rhombic distortion of the zfs [E/D = 0.31(1), D > 0]. DC magnetic susceptibility experiments on 1 and analysis of the data constraining the E/D value obtained by EPR yielded g = 2.595(7), |D| = 61(1) cm-1, and an intradimer ferromagnetic exchange coupling of J = 1.39(4) cm-1. EPR spectra as a function of Co : Zn ratio for both powder and single crystal samples confirmed that they result from two effective S' = 1/2 spins that interact through dipolar and isotropic exchange interactions to yield magnetically isolated S' = 1 centres and that interdimeric exchange interactions, putatively mediated by hydrophobic interactions between phen moieties, are negligible. The latter observation contrasts with that observed in the Cu(II) analogue, where a transition from S = 1 to S' = 1/2 was observed. Computational calculations indicated that the absence of the interdimeric exchange interaction in 1 is due to a lower Co(II) ion spin density delocalisation towards the metal ligands.
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Tropical pelagic predators are exploited by fisheries and their movements are influenced by factors including prey availability, temperature, and dissolved oxygen levels. As the biophysical parameters vary greatly within the range of circumtropical species, local studies are needed to define those species' habitat preference and model possible behavioral responses under different climate change scenarios. Here, we tagged yellowfin tuna Thunnus albacares in the Galápagos Marine Reserve and tracked the horizontal and vertical movements of eight individuals for 4-97 days. The tuna traveled a mean of 13.6 km day-1 horizontally and dispersed throughout the archipelago and in offshore waters inside the Galápagos Marine Reserve and in the surrounding Ecuadorian exclusive economic zone. Vertically, they traveled a mean of 2 km day-1 , although high-resolution data from a recovered tag suggested that transmitted data underestimated their vertical movement by a factor of 5.5. The tracked yellowfin tuna spent most of their time near the surface, with an overall mean swimming depth of 24.3 ± 46.6 m, and stayed shallower at night (11.1 ± 16.3 m) than during the day ( 37.7 ± 60.9 m), but on occasion dived to cold, oxygen-poor waters below 200 m. Deep dives were commonly made during the day with a mean recovery period of 51 min between exposures to modeled oxygen-limiting conditions <1.5 mL L-1 , presumably to re-oxygenate. The depth and frequency of dives were likely limited by dissolved oxygen levels, as oxygen-depleted conditions reach shallow depths in this region. The main habitat of tracked yellowfin tunas was in the shallow mixed layer, which may leave them vulnerable to fishing. Vertical expansion of low-oxygen waters under future climate change scenarios may further compress their habitat, increasing their vulnerability to surface fishing gear.
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Oxigênio , Atum , Humanos , Animais , Atum/fisiologia , Temperatura , Mudança Climática , EcossistemaRESUMO
The objective of this research was to create and appraise biodegradable polymer-based nanofibers containing distinct concentrations of calcium trimetaphosphate (Ca-TMP) for periodontal tissue engineering. Poly(ester urea) (PEU) (5% w/v) solutions containing Ca-TMP (15%, 30%, 45% w/w) were electrospun into fibrous scaffolds. The fibers were evaluated using SEM, EDS, TGA, FTIR, XRD, and mechanical tests. Degradation rate, swelling ratio, and calcium release were also evaluated. Cell/Ca-TMP and cell/scaffold interaction were assessed using stem cells from human exfoliated deciduous teeth (SHEDs) for cell viability, adhesion, and alkaline phosphatase (ALP) activity. Analysis of variance (ANOVA) and post-hoc tests were used (α = 0.05). The PEU and PEU/Ca-TMP-based membranes presented fiber diameters at 469 nm and 414-672 nm, respectively. Chemical characterization attested to the Ca-TMP incorporation into the fibers. Adding Ca-TMP led to higher degradation stability and lower dimensional variation than the pure PEU fibers; however, similar mechanical characteristics were observed. Minimal calcium was released after 21 days of incubation in a lipase-enriched solution. Ca-TMP extracts enhanced cell viability and ALP activity, although no differences were found between the scaffold groups. Overall, Ca-TMP was effectively incorporated into the PEU fibers without compromising the morphological properties but did not promote significant cell function.