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Zebrafish have become an important model animal for studying the emergence of collective behavior in nature. Here, we show how to properly analyze the polarization statistics to distinguish shoal regimes. In analogy with the statistical properties of optical speckles, we show that exponential and Rayleigh distributions emerge in shoals with many fish with uncorrelated velocity directions. In the opposite limit of just two fish, the polarization distribution peaks at high polarity, with the average value being a decreasing function of the shoal's size, even in the absence of correlations. We also perform a set of experiments unveiling two shoaling regimes. Large shoals behave as small domains with strong intra-domain and weak inter-domain correlations. A strongly correlated regime develops for small shoals. The reported polarization statistical features shall guide future automated neuroscience, pharmacological, toxicological, and embryogenesis-motivated experiments aiming to explore the collective behavior of fish shoals.
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Comportamento Animal , Peixe-Zebra , Animais , Peixe-Zebra/fisiologia , Comportamento SocialRESUMO
OBJECTIVES: Fetal echocardiography is the gold standard modality to detect suspected congenital heart disease (CHD). Accurate diagnosis and subsequent prognosis is even more challenging in the presence of a raised maternal body mass index (BMI). This retrospective study aimed to gain insight into the prevalence of obesity within the cohort of patients referred for fetal echocardiography. STUDY DESIGN/METHODS: Retrospective analysis of all pregnant patients referred to the Scottish National Fetal Cardiology Service between 2015 and 2021 due to a suspected fetal cardiac abnormality and examining the associated trends in maternal BMI and the Scottish Index of Multiple Deprivation (SIMD). RESULTS: BMI data were available for 962 (96.3%) of the 998 patients referred during the study period. Median BMI during the study period was 31. BMI range in the seven-year period was 16-63. There was no association between BMI group and year (P = 0.889). A median of 58% of patients referred were classified as overweight (BMI > 25 kg/m2), and only 37% were reported to have a BMI within normal limits. Referral BMI was relatively consistent in the seven years with no dramatic increase in the obese categories. Mean BMI in SIMD 5 (lowest level of deprivation), was significantly lower (P = 0.001), than in SIMD 1 (highest deprivation). CONCLUSIONS: People of child bearing age should be aware the potential limitations that a raised BMI may have upon diagnostic/screening accuracy impacting subsequent ability to provide accurate fetal cardiac diagnoses and prognostic fetal cardiac imaging.
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Índice de Massa Corporal , Ecocardiografia , Cardiopatias Congênitas , Ultrassonografia Pré-Natal , Humanos , Feminino , Gravidez , Estudos Retrospectivos , Adulto , Ecocardiografia/estatística & dados numéricos , Ultrassonografia Pré-Natal/estatística & dados numéricos , Escócia/epidemiologia , Cardiopatias Congênitas/diagnóstico por imagem , Cardiopatias Congênitas/epidemiologia , Obesidade/epidemiologia , Adulto Jovem , PrevalênciaRESUMO
In this work, we study the polarization time series obtained from experimental observation of a group of zebrafish (Danio rerio) confined in a circular tank. The complex dynamics of the individual trajectory evolution lead to the appearance of multiple characteristic scales. Employing the Multifractal Detrended Fluctuation Analysis (MF-DFA), we found distinct behaviors according to the parameters used. The polarization time series are multifractal at low fish densities and their average scales with ρ - 1 / 4 . On the other hand, they tend to be monofractal, and their average scales with ρ - 1 / 2 for high fish densities. These two regimes overlap at critical density ρ c , suggesting the existence of a phase transition separating them. We also observed that for low densities, the polarization velocity shows a non-Gaussian behavior with heavy tails associated with long-range correlation and becomes Gaussian for high densities, presenting an uncorrelated regime.
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Fractais , Peixe-Zebra , Peixe-Zebra/fisiologia , AnimaisRESUMO
OBJECTIVES: During the COVID-19 pandemic, public health measures were used to reduce the spread of COVID-19; it is unknown whether people with chronic conditions differentially adhered to public health measures. The objectives of this study were to evaluate the association between chronic conditions and adherence and to explore effect modification by sex, age, and income. STUDY DESIGN: An analysis of data from the Canadian Longitudinal Study on Aging COVID-19 Questionnaires (from April to September 2020) was conducted among middle-aged and older adults aged 50-96 years (n = 28,086). METHODS: Self-reported chronic conditions included lung disease, diabetes, heart disease, cancer, obesity, anxiety, and depression. Multinomial logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the association between chronic conditions and low, medium, and high levels of adherence. Effect modification was evaluated using statistical interaction and stratification. RESULTS: Most people (n = 17,435; 62%) had at least one chronic condition, and 2866 (10%) had three to seven chronic conditions. Among those with high adherence to public health measures, 69% had one or more chronic condition (n = 2266). Having three to seven chronic conditions, compared with none, was associated with higher adherence to public health measures (OR: 2.14; 95% CI: 1.12-1.42). Higher adherence was also noted across chronic conditions, for example, those with diabetes had higher adherence (OR: 1.72; 95% CI: 1.53-1.93). There was limited evidence of effect modification by sex, age, or income. CONCLUSIONS: Canadians with chronic conditions were more likely to adhere to public health measures; however, future research is needed to understand whether adherence helped to prevent adverse COVID-19 outcomes and if adherence had unintended consequences.
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COVID-19 , Autorrelato , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Pessoa de Meia-Idade , Masculino , Canadá/epidemiologia , Feminino , Idoso , Estudos Longitudinais , Doença Crônica/epidemiologia , Idoso de 80 Anos ou mais , Saúde Pública , SARS-CoV-2RESUMO
BACKGROUND: Rates of antimicrobial resistance (AMR) for some pathogens in Australia are considerably higher in rural and remote compared to urban regions. The inaugural Hot North Antimicrobial Academy was a 9-month educational programme aimed to build workforce knowledge and capacity in antimicrobial use, audit, stewardship, surveillance and drug resistance in remote primary health care. METHODS: The Academy was advertised to Aboriginal and Torres Strait Islander, regional and remote healthcare workers. Participants were Aboriginal health practitioners, nurses, pharmacists and doctors from Queensland, Northern Territory, South Australia and Western Australia working in remote primary health care with a focus on Indigenous health. Due to COVID-19 restrictions, the Academy ran virtually from February-November 2021 using Microsoft Teams. The Academy was evaluated using surveys and yarning circles to assess impact and knowledge gain. RESULTS: Participants and faculty from across Australia attended 19 lectures and mentorship sessions. Eleven participants commenced and eight (73%) completed the Academy. The Academy raised participants awareness of AMR guidelines, governance and generating change; built confidence in advocacy; grew knowledge about drug resistant infections; and created a community of AMR champions in Indigenous health. CONCLUSION: The evaluation confirmed the Academy met the needs of participants, provided opportunities to move stewardship from tertiary hospitals into Indigenous and remote clinics and developed skills in research, audit, stewardship and advocacy for all involved. All sessions were recorded for future use, with facilitation by the National Aboriginal Community Controlled Health Organisation (NACCHO) in future years.
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Gestão de Antimicrobianos , Fortalecimento Institucional , Resistência Microbiana a Medicamentos , Humanos , Antibacterianos/farmacologia , Austrália , COVID-19/prevenção & controle , Farmacorresistência Bacteriana , Serviços de Saúde do Indígena , Atenção Primária à Saúde , Saúde da População RuralRESUMO
This is the first report describing detailed T cell responses to viral-like proteins contained in an HPV specific vaccine given in combination with Imiquimod for treatment of persistent VAIN2/3. We postulate that stimulation of the innate immune system with Imiquimod and the specific CD4 and CD8T cell responses following HPV vaccination with Gardasil9@ combined to induce clinical remission in a woman with treatment-refractory disease.
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With the advent of novel and emerging technologies, long duration spaceflight will become more common; along with it, an increase in its inherent health risks. However, health-related ethical issues arising during long-duration spaceflight remain poorly characterized, uncertain and unpredictable. Medical ethics is defined as a set of moral principles, beliefs and values that guides choices about medical care. This set of principles, founded in our sense of right and wrong, helps us make fair and just decisions. The paper conceptually and analytically investigates the ethical issues likely to arise from medical complications during spaceflight, mapping unfilled gaps of the current status quo. Furthermore, this paper explores broad ethical themes of autonomy, nonmaleficence, beneficence and justice, while also delving deeper into specific scenarios within each theme. The manuscript represents an up-to-date review of the available literature in the field of space medical ethics and recommends guiding ethical principles and a framework for their application to negotiate the resolution of complex ethical scenarios during long-duration spaceflight.
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The purpose of this study was to characterize the role of ß1-AR signaling and its cross-talk between cardiac renin-angiotensin system and thyroid-hormone-induced cardiac hypertrophy. T3 was administered at 0.5 mg·kg-1·day-1 for 10 days in ß1-KOT3 and WTT3 groups, while control groups received vehicle alone. Echocardiography and myocardial histology was performed; cardiac and serum ANGI/ANGII and ANP and cardiac levels of p-PKA, p-ERK1/2, p-p38-MAPK, p-AKT, p-4EBP1, and ACE were measured. WTT3 showed decreased IVSTd and increased LVEDD versus WTsal (p < 0.05). ß1-KOT3 exhibited lower LVEDD and higher relative IVSTd versus ß1-KOsal, the lowest levels of ejection fraction, and the highest levels of cardiomyocyte diameter (p < 0.05). Cardiac ANP levels decreased in WTT3 versus ß1-KOT3 (p < 0.05). Cardiac ACE expression was increased in T3-treated groups (p < 0.05). Phosphorylated-p38 MAPK levels were higher in WTT3 versus WTsal or ß1-KOT3, p-4EBP1 was elevated in ß1-KO animals, and p-ERK1/2 was up-regulated in ß1-KOT3. These findings suggest that ß1-AR signaling is crucial for TiCH.
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Cardiomiopatia Restritiva , Camundongos , Animais , Cardiomiopatia Restritiva/metabolismo , Cardiomiopatia Restritiva/patologia , Camundongos Knockout , Miocárdio/metabolismo , Hormônios Tireóideos , Receptores Adrenérgicos/metabolismo , Angiotensina II/farmacologiaRESUMO
The health risks associated with manganese (Mn) in drinking water, and an improved understanding of Mn accumulation within, and subsequent release from, distribution systems, have increased the need for robust, sustainable treatment options to minimize Mn concentrations in finished water. Biofiltration is an established and effective method to remove Mn in groundwater however, Mn removal in surface water biofilters is an emerging treatment process that has not been extensively studied. Seasonal variations in water temperature can present an operational challenge for surface water biofilters which may see reduced Mn removal under colder conditions. This study examined the microbiomes of surface water biofilters at three utilities (ACWD WTP, WTP B, and WTP D) which all experienced similar seasonal fluctuations in influent water temperature. High Mn removal was observed at the ACWD WTP for much of the year, but Mn removal decreased with a concurrent decrease in the influent water temperature (58% ± 22%). In contrast, both WTP B and WTP D achieved year-round Mn removal (84% ± 5% and 93% ± 8% respectively). Marker gene (16S rRNA) sequencing analysis of the biofilter microbiomes identified a high abundance of Betaproteobacteria in WTP B and WTP D (37% ± 12% and 21% ± 3% respectively), but a low abundance of Betaproteobacteria in the ACWD WTP (2% ± 2%). The microbiomes of new bench-scale biofilters, in operation at the ACWD WTP, were also investigated. The abundance of Betaproteobacteria was significantly greater (p < 0.05) after the biofilters had acclimated than before acclimation, and differential abundance analysis identified 6 genera within the Betaproteobacteria class were enriched in the acclimated microbiome. Additionally, the acclimated biofilters were able to maintain high Mn removal performance (87% ± 10%) when the influent water temperature decreased to 10 °C or less. Further analysis of previously published studies found the abundance of Betaproteobacteria was also significantly greater (p < 0.001) in biofilters with sustained Mn removal than in biofilters which did not treat for Mn as a contaminant, despite differences in design scale, source water, and media type. Microbiome network analysis identified multiple co-occurrence relationships between Betaproteobacteria and Mn oxidizing bacteria in the WTP B and WTP D biofilters, suggesting indirect contributions by Betaproteobacteria to biological Mn oxidation. These co-occurrence relationships were not present in the full-scale ACWD WTP microbiome. Whether the role of Betaproteobacteria in biological Mn oxidation is direct, indirect, or a combination of both, they are consistently present at a high abundance in both groundwater and surface water biofilters with sustained Mn removal, and their absence may contribute to the seasonal fluctuations in Mn removal observed at the ACWD WTP. This new insight to Betaproteobacteria and their role in Mn biofiltration could contribute to water innovation and design that would improve the reliability of Mn removal.
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Água Potável , Purificação da Água , Manganês , Temperatura , RNA Ribossômico 16S , Reprodutibilidade dos Testes , Purificação da Água/métodos , FiltraçãoAssuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Humanos , Rifampina/uso terapêutico , Antituberculosos/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Fumar/efeitos adversos , Fumar/epidemiologia , Resultado do Tratamento , IsoniazidaRESUMO
A ring trial among five European laboratories was organized to reach consistency in microsatellite (MS) typing of the zoonotic parasite Toxoplasma gondii. Three sample sets were circulated and analyzed by each laboratory following a previously published method that is based on fragment length polymorphism of 15 MS markers. The first sample set compared typing results in general and focused on effects of DNA concentration; the second sample set focused on the polymorphic fingerprinting markers that can differentiate T. gondii strains within the same archetypal lineage; and the third set focused on non-archetypal genotypes. Methodological variations between laboratories, including the software programs used to determine MS fragment length, were collated using a questionnaire. Overall, lineage-level typing results reached a high level of agreement, especially in samples with the highest DNA concentrations. However, laboratory-specific differences were observed for particular markers. Major median differences in fragment length, of up to 6 base pairs, were related to the fluorophore used to label fragment-specific primers. In addition, primer pairs with identical sequences obtained from different suppliers resulted in fragments of differing length. Furthermore, differences in the way the sequencing profiles were assessed and interpreted may have led to deviating results in fragment length determination. Harmonization of MS typing, for example, by using the same fluorophores or by numerical adjustments applied to the fragment-lengths determined, could improve the uniformity of the results across laboratories. This is the first interlaboratory comparison, providing guidelines (added as a supplement) for the optimization of this technique.
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Toxoplasma , Toxoplasmose Animal , Humanos , Animais , Toxoplasma/genética , Variação Genética , Polimorfismo de Fragmento de Restrição , DNA de Protozoário/genética , Repetições de Microssatélites , GenótipoRESUMO
Individuals with lower-limb amputations may have a significant strength deficit. This deficit may be related to the stump length and can lead to changes in gait, reduced energy efficiency, walking resistance, altered joint load, and increased risk of osteoarthritis and chronic low back pain. This systematic review used the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA) guidelines to examine the effects of resistance training in lower limb amputees. Interventions with resistance training and other training methods were sufficient to achieve muscle strength gain in muscles of the lower limbs, improved balance, and improvements in gait pattern and speed when walking. However, it was impossible to determine from the results whether resistance training was mainly responsible for these benefits or even whether the positive effects presented would be observed with only this training method. When combined with other exercises, interventions with resistance training made possible gains for this population. Accordingly, it is noteworthy that the main finding of this systematic review is that the effects may be different according to the level of amputation, with mainly transtibial and transfemoral amputations studied.
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We investigate the propagation of waves in one-dimensional systems with Lévy-type disorder. We perform a complete analysis of nonrelativistic and relativistic wave transmission submitted to potential barriers whose width, separation, or both follow Lévy distributions characterized by an exponent 0<α<1. For the first two cases, where one of the parameters is fixed, nonrelativistic and relativistic waves present anomalous localization, ãTãâL^{-α}. However, for the latter case, in which both parameters follow a Lévy distribution, nonrelativistic and relativistic waves present a transition between anomalous and standard localization as the incidence energy increases relative to the barrier height. Moreover, we obtain the localization diagram delimiting anomalous and standard localization regimes, in terms of incidence angle and energy. Finally, we verify that transmission fluctuations, characterized by its standard deviation, are universal, independent of barrier architecture, wave equation type, incidence energy, and angle, further extending earlier studies on electronic localization.
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The World Health Organization has declared the novel coronavirus disease 2019 (COVID-19) a global public health emergency. Despite the predominating respiratory symptoms occurring in COVID-19, thrombosis can occur in some patients, with morbidity and mortality increase due to the respiratory worsening. This article reports the case of a 62-year-old man with a flu-like illness that was diagnosed as COVID-19 by RT-PCR of SARS-CoV-2. After three weeks, he subsequently developed abdominal pain in addition to bloating, nausea, and vomiting. He underwent exploratory laparotomy after imaging tests suggested mesenteric ischemia. Intestinal ischemia was evident, due to the absence of flow in the superior mesenteric artery and jejunal branches. Embolectomy and enterectomy were performed and they resulted in a favorable outcome, with clinical improvement. This case adds data to the limited literature on extrapulmonary complications of COVID-19, notably those related to thromboembolic events.
La Organización Mundial de la Salud ha declarado la enfermedad del nuevo coronavirus 2019 (COVID-19) una emergencia de salud pública mundial. A pesar de los síntomas respiratorios predominantes en COVID-19, la trombosis puede ocurrir en algunos pacientes, con un aumento de la morbimortalidad debido al empeoramiento respiratorio. Presentamos el caso de un hombre de 62 años con enfermedad similar a la gripe que fue diagnosticada como COVID-19 por RT-PCR de SARS-CoV-2. Después de tres semanas, desarrolló dolor abdominal además de hinchazón, náuseas y vómitos. Fue sometido a laparotomía exploradora luego de que las pruebas de imagen sugirieran isquemia mesentérica. Se evidenció isquemia intestinal por ausencia de flujo en la arteria mesentérica superior y ramas yeyunales. Se realizó embolectomía y enterectomía con evolución favorable, con mejoría clínica. Este caso añade datos a la limitada literatura sobre las complicaciones extrapulmonares del COVID-19, en particular las relacionadas con eventos tromboembólicos.
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COVID-19 , Tromboembolia , Trombose , COVID-19/complicações , Humanos , Masculino , Artéria Mesentérica Superior/diagnóstico por imagem , Pessoa de Meia-Idade , SARS-CoV-2 , Tromboembolia/complicações , Tromboembolia/etiologia , Trombose/diagnóstico por imagemRESUMO
Abstract The World Health Organization has declared the novel coronavirus disease 2019 (COVID-19) a global public health emergency. Despite the predominating respiratory symptoms occurring in COVID-19, thrombosis can occur in some patients, with morbidity and mortality increase due to the respiratory worsening. This article reports the case of a 62-year-old man with a flu-like illness that was diagnosed as CO VID-19 by RT-PCR of SARS-CoV-2. After three weeks, he subsequently developed abdominal pain in addition to bloating, nausea, and vomiting. He underwent exploratory laparotomy after imaging tests suggested mesenteric ischemia. Intestinal ischemia was evident, due to the absence of flow in the superior mesenteric artery and jejunal branches. Embolectomy and enterectomy were performed and they resulted in a favorable outcome, with clinical improvement. This case adds data to the limited literature on extrapulmonary complications of COVID-19, notably those related to thromboembolic events.
Resumen La Organización Mundial de la Salud ha declarado la enfermedad del nuevo coronavirus 2019 (COVID-19) una emergencia de salud pública mundial. A pesar de los síntomas respiratorios predominantes en COVID-19, la trombosis puede ocurrir en algunos pacientes, con un aumento de la morbimortalidad debido al empeoramiento respiratorio. Presentamos el caso de un hombre de 62 años con enfermedad similar a la gripe que fue diagnosticada como COVID-19 por RT-PCR de SARS-CoV-2. Después de tres semanas, de sarrolló dolor abdominal además de hinchazón, náuseas y vómitos. Fue sometido a laparotomía exploradora luego de que las pruebas de imagen sugirieran isquemia mesentérica. Se evidenció isquemia intestinal por ausencia de flujo en la arteria mesentérica superior y ramas yeyunales. Se realizó embolectomía y enterec tomía con evolución favorable, con mejoría clínica. Este caso añade datos a la limitada literatura sobre las complicaciones extrapulmonares del COVID-19, en particular las relacionadas con eventos tromboembólicos.
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We offer a new perspective on the problem of characterizing mesoscopic fluctuations in the interplateau regions of the integer quantum Hall transition. We found that longitudinal and transverse conductance fluctuations, generated by varying the external magnetic field within a microscopic model, are multifractal and lead to distributions of conductance increments (magnetoconductance) with heavy tails (intermittency) and signatures of a hierarchical structure (cascade) in the corresponding stochastic process, akin to Kolmogorov's theory of fluid turbulence. We confirm this picture by interpreting the stochastic process of the conductance increments in the framework of H theory, which is a continuous-time stochastic approach that incorporates the basic features of Kolmogorov's theory. The multifractal analysis of the conductance "time series," combined with the H-theory formalism, provides strong support for the overall characterization of mesoscopic fluctuations in the quantum Hall transition as a multifractal stochastic phenomenon with multiscale hierarchy, intermittency, and cascade effects.
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Here, we describe 4-dimethylaminoantipyrine (4-DMAA)-mediated interfacing as a broad biochemical indicator to stabilize and promote the higher response of electrodes for immunological detection. We hypothesized that the improved biological interactions of 4-DMAA with electrodes and biological samples may be due to the interaction properties of the benzene and pyrazole chemical groups with graphite and proteins, respectively. In order to demonstrate that 4-DMAA could be used as a general indicator in electrochemical immunoassays, we used peptides as probes for the diagnosis of four neglected tropical infectious diseases Tegumentary leishmaniasis, Visceral leishmaniasis, Strongyloidiasis, and Leprosy on commercial graphite screen-printed electrodes. 4-DMAA oxidation was used to indicate specific biological recognition between the epitope-based peptide and serum immunoglobulin G (IgG) from infected patients. We demonstrated that 4-DMAA should be incorporated into the electrodes prior to serum application, which avoids interference with its sensitivity and specificity. In addition, 4-DMAA oxidizes at a low anodic potential, and the oxidation peak is useful for detecting proteins in biological fluids. In summary, we have successfully demonstrated the broad application of 4-DMAA as a general indicator for the specific diagnosis of four infectious diseases in electrochemical immunosensors. Such a strategy is quite advantageous for indirect detection of proteins that lack electrochemical activities or are spatially inaccessible on the electrode surface. This new indicator opens a new avenue for monitoring biological recognition, especially for immunosensors.
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Técnicas Biossensoriais , Grafite , Aminopirina , Eletrodos , Humanos , ImunoensaioRESUMO
Purpose: To report successful ring-shaped iodine-125 plaque brachytherapy for conjunctival melanoma. Observations: Eye Physics (EP) plaque brachytherapy, designed with Plaque Simulator software, proved to be an effective treatment modality with some corneal irritation and no recurrence at 12-months post radiation. Conclusion and importance: Management of conjunctival melanoma is complicated by the lack of gold standard adjuvant treatments. I-125 EP plaque brachytherapy represents a viable option for these malignancies. Specifically, ring-shaped plaque geometries allow for targeted radiotherapy.
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Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Mutação , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologiaRESUMO
Dissolved organic carbon (DOC) is often related to the brownification of water in continental aquatic systems and to changes in the physiology of zooplankton organisms. Zooplankton resting eggs are particularly sensitive to changes in light and chemical characteristics of water, but the physical and chemical effects associated to DOC on dormant stages have never been tested before. Herein, we tested how DOC affects hatching rates and time to hatching of Cladocera (Diaphanosoma birgei) resting eggs. In order to analyze the chemical (i.e., toxic) and physical (i.e., light attenuation) effects of DOC on hatching patterns, resting eggs were exposed to different concentrations of DOC (0, 50, and 100 mg L-1) in an experimental design which isolated chemical from physical effects. When evaluating the physical effects of DOC, hatching was more than 150% less in 100 than 50 mg L-1 DOC and time to hatching was 66% lesser in 50 mg L-1 DOC than control. Hatchling numbers and time to hatching were not affected by DOC chemical effects. We conclude DOC effects on hatching mainly relied on light attenuation, while chemical effects were likely of minor importance. DOC may change Cladocera emergence patterns mainly through light attenuation in the water column.