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1.
Sensors (Basel) ; 24(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38894161

RESUMO

Technological advancements have expanded the range of methods for capturing human body motion, including solutions involving inertial sensors (IMUs) and optical alternatives. However, the rising complexity and costs associated with commercial solutions have prompted the exploration of more cost-effective alternatives. This paper presents a markerless optical motion capture system using a RealSense depth camera and intelligent computer vision algorithms. It facilitates precise posture assessment, the real-time calculation of joint angles, and acquisition of subject-specific anthropometric data for gait analysis. The proposed system stands out for its simplicity and affordability in comparison to complex commercial solutions. The gathered data are stored in comma-separated value (CSV) files, simplifying subsequent analysis and data mining. Preliminary tests, conducted in controlled laboratory environments and employing a commercial MEMS-IMU system as a reference, revealed a maximum relative error of 7.6% in anthropometric measurements, with a maximum absolute error of 4.67 cm at average height. Stride length measurements showed a maximum relative error of 11.2%. Static joint angle tests had a maximum average error of 10.2%, while dynamic joint angle tests showed a maximum average error of 9.06%. The proposed optical system offers sufficient accuracy for potential application in areas such as rehabilitation, sports analysis, and entertainment.


Assuntos
Algoritmos , Antropometria , Análise da Marcha , Marcha , Humanos , Antropometria/métodos , Marcha/fisiologia , Análise da Marcha/métodos , Análise da Marcha/instrumentação , Masculino , Fenômenos Biomecânicos , Adulto , Captura de Movimento
2.
Comput Med Imaging Graph ; 115: 102390, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38714018

RESUMO

Colonoscopy is the choice procedure to diagnose, screening, and treat the colon and rectum cancer, from early detection of small precancerous lesions (polyps), to confirmation of malign masses. However, the high variability of the organ appearance and the complex shape of both the colon wall and structures of interest make this exploration difficult. Learned visuospatial and perceptual abilities mitigate technical limitations in clinical practice by proper estimation of the intestinal depth. This work introduces a novel methodology to estimate colon depth maps in single frames from monocular colonoscopy videos. The generated depth map is inferred from the shading variation of the colon wall with respect to the light source, as learned from a realistic synthetic database. Briefly, a classic convolutional neural network architecture is trained from scratch to estimate the depth map, improving sharp depth estimations in haustral folds and polyps by a custom loss function that minimizes the estimation error in edges and curvatures. The network was trained by a custom synthetic colonoscopy database herein constructed and released, composed of 248400 frames (47 videos), with depth annotations at the level of pixels. This collection comprehends 5 subsets of videos with progressively higher levels of visual complexity. Evaluation of the depth estimation with the synthetic database reached a threshold accuracy of 95.65%, and a mean-RMSE of 0.451cm, while a qualitative assessment with a real database showed consistent depth estimations, visually evaluated by the expert gastroenterologist coauthoring this paper. Finally, the method achieved competitive performance with respect to another state-of-the-art method using a public synthetic database and comparable results in a set of images with other five state-of-the-art methods. Additionally, three-dimensional reconstructions demonstrated useful approximations of the gastrointestinal tract geometry. Code for reproducing the reported results and the dataset are available at https://github.com/Cimalab-unal/ColonDepthEstimation.


Assuntos
Colo , Colonoscopia , Bases de Dados Factuais , Humanos , Colonoscopia/métodos , Colo/diagnóstico por imagem , Redes Neurais de Computação , Pólipos do Colo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos
3.
Rev. ADM ; 81(2): 109-113, mar.-abr. 2024. ilus
Artigo em Espanhol | LILACS | ID: biblio-1562634

RESUMO

Si bien el conocimiento científico para el tratamiento de la periimplantitis ha avanzado significativamente en los últimos años, sigue en discusión qué tipo de abordaje quirúrgico genera los mejores resultados clínicos y si el uso de biomateriales da mejoras significativas en dicho tratamiento. Este reporte de caso describe un abordaje quirúrgico reconstructivo de un defecto intraóseo por periimplantitis en una paciente que refería dolor y un intenso sangrado en sus implantes dentales, empleando un sustituto óseo anorgánico mineral bovino, sin el uso de una membrana o barrera, y con un protocolo de descontaminación de la superficie del implante mecánico y químico. Posteriormente, a las 20 semanas de realizado el procedimiento, se hizo la evaluación del defecto, obteniendo profundidades al sondeo menores a 5 mm, ausencia de sangrado al sondeo en todos los sitios y un llenado óseo radiográfico de aproximadamente 90%; cumpliendo con los criterios de éxito de la terapia periimplantaria. Lo anterior muestra que la terapia reconstructiva para los defectos por periimplantitis puede ser posible mediante el uso de un sustituto óseo xenogénico únicamente y con una correcta descontaminación de la superficie del implante (AU)


Although scientific knowledge for the treatment of peri-implantitis have advanced significantly in recent years, the type of surgical approach that generates the best clinical results is still under discussion and whether the use of biomaterials gives significant improvements in said treatment. This case report describes a reconstructive surgical approach for a periimplantitis intrabony defect using an anorganic bovine bone substitute, without the use of a membrane or barrier, and with a mechanical and chemical implant surface decontamination protocol. Twenty weeks after the procedure, the defect was reassessed, obtaining probing depths of less than 5 mm, no bleeding on probing in all sites, and radiographic bone filling of approximately 90%; meeting the success criteria for the peri-implant therapy. This shows that reconstructive therapy for periimplantitis defects may be possible using a xenogeneic bone substitute only and proper decontamination of the implant surface (AU)


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Substitutos Ósseos/uso terapêutico , Procedimentos Cirúrgicos Bucais/métodos , Implantação Dentária Endóssea/efeitos adversos , Peri-Implantite/cirurgia , Bolsa Periodontal/diagnóstico , Retalhos Cirúrgicos , Escovação Dentária/métodos , Índice Periodontal , Descontaminação/métodos , México
4.
Comput Biol Med ; 172: 108167, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38461699

RESUMO

In recent decades, many studies have been published on the use of automatic smear microscopy for diagnosing pulmonary tuberculosis (TB). Most of them deal with a preliminary step of the diagnosis, the bacilli detection, whereas sputum smear microscopy for diagnosis of pulmonary TB comprises detecting and reporting the number of bacilli found in at least 100 microscopic fields, according to the 5 grading scales (negative, scanty, 1+, 2+ and 3+) endorsed by the World Health Organization (WHO). Pulmonary TB diagnosis in bright-field smear microscopy, however, depends upon the attention of a trained and motivated technician, while the automated TB diagnosis requires little or no interpretation by a technician. As far as we know, this work proposes the first automatic method for pulmonary TB diagnosis in bright-field smear microscopy, according to the WHO recommendations. The proposed method comprises a semantic segmentation step, using a deep neural network, followed by a filtering step aiming to reduce the number of false positives (false bacilli): color and shape filtering. In semantic segmentation, different configurations of encoders are evaluated, using depth-wise separable convolution layers and channel attention mechanism. The proposed method was evaluated with a large, robust, and annotated image dataset designed for this purpose, consisting of 250 testing sets, 50 sets for each of the 5 TB diagnostic classes. The following performance metrics were obtained for automatic pulmonary TB diagnosis by smear microscopy: mean precision of 0.894, mean recall of 0.896, and mean F1-score of 0.895.


Assuntos
Mycobacterium tuberculosis , Tuberculose Pulmonar , Humanos , Microscopia/métodos , Tuberculose Pulmonar/diagnóstico por imagem , Redes Neurais de Computação , Sensibilidade e Especificidade
5.
BMC Med Ethics ; 25(1): 16, 2024 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336668

RESUMO

BACKGROUND: The COVID-19 pandemic has influenced the approach to the health-disease system, raising the question about the principles of bioethics present in physician-patient relations. The principles while widely accepted may not be sufficient for a comprehensive ethical analysis. Therefore, the aim of this study was to explore the perception of these principles and the physician-patient relationship during a hospital stay through a qualitative approach. METHOD: Sixteen semi-structured interviews took place to know the patients' perception during their 2020 hospitalization for COVID-19. The data was analyzed through the constant comparison method, creating categories and comparing them. In the end, seven categories were established and were grouped in three: bioethical principles (dignity, charity, vulnerability, autonomy), doctor-patient relationship (participant commitment, informed consent, health staff-patient relationship) and the experience of the disease (illness, the role of the family). RESULTS: The research found that most patients described a positive experience, with the feeling of having been well cared for with no sense of discrimination or injustice done. The majority also reported that their autonomy was respected in the treatment decisions. The evaluation of these attitudes is an area of opportunity, especially when the patients' vulnerability is at risk. CONCLUSIONS: The ethics of virtue offers a better reflection of how human beings manifest themselves by emphasizing the development of virtuous character and behaviors that allow them to realize their values in life. Authorized by the Research Ethics Committee with registration: DI/18/105-B/3/308.


Assuntos
Bioética , COVID-19 , Médicos , Humanos , Relações Médico-Paciente , Pandemias
6.
J Oral Pathol Med ; 53(2): 107-113, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38355113

RESUMO

BACKGROUND: Tongue cancer is associated with debilitating diseases and poor prognostic outcomes. The use of imaging techniques like ultrasonography to assist in the clinical management of affected patients is desirable, but its reliability remains debatable. Therefore, the aim of this study is to investigate the importance of ultrasound use for the clinicopathological management of tongue cancer. METHODS: A scoping review was carried out using specific search strategies in the following electronic databases: PubMed/MEDLINE, Scopus, Web of Science, and Google Scholar. Collected data included bibliographical information, study design, ultrasound equipment, the aim of the ultrasonography use, the timing of ultrasound use during oncological treatment (pre-, trans-, and/or post-operatively), and the advantages and disadvantages of the use of the ultrasound. RESULTS: A total of 47 studies were included in this review after following the selection process. The majority of the studies investigated the use of ultrasound pre-operatively for the investigation of lymph node metastases or to determine the tumor thickness and depth of invasion. The sensitivity, specificity, and accuracy of ultrasound to determine clinical lymph node metastases ranged from 47% to 87.2%, from 84.3% to 95.8%, and from 70% to 86.2%, respectively. The sensitivity and specificity to determine the microscopic depth of invasion were 92.3% and from 70.6% to 82.1%, respectively. CONCLUSION: Ultrasonography seems to be a reliable imaging technique for the investigation of important prognostic parameters for tongue cancer, including depth of invasion and lymph node metastases.


Assuntos
Neoplasias da Língua , Humanos , Neoplasias da Língua/diagnóstico por imagem , Neoplasias da Língua/terapia , Neoplasias da Língua/patologia , Metástase Linfática/diagnóstico por imagem , Metástase Linfática/patologia , Reprodutibilidade dos Testes , Ultrassonografia , Prognóstico , Estadiamento de Neoplasias , Linfonodos/patologia
7.
J Phycol ; 60(2): 483-502, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38264946

RESUMO

Kelp communities are experiencing exacerbated heat-related impacts from more intense, frequent, and deeper marine heatwaves (MHWs), imperiling the long-term survival of kelp forests in the climate change scenario. The occurrence of deep thermal anomalies is of critical importance, as elevated temperatures can impact kelp populations across their entire bathymetric range. This study evaluates the impact of MHWs on mature sporophytes of Pterygophora californica (walking kelp) from the bathymetric extremes (8-10 vs. 25-27 m) of a population situated in Baja California (Mexico). The location is near the southernmost point of the species's broad distribution (from Alaska to Mexico). The study investigated the ecophysiological responses (e.g., photobiology, nitrate uptake, oxidative stress) and growth of adult sporophytes through a two-phase experiment: warming simulating a MHW and a post-MHW phase without warming. Generally, the effects of warming differed depending on the bathymetric origin of the sporophytes. The MHW facilitated essential metabolic functions of deep-water sporophytes, including photosynthesis, and promoted their growth. In contrast, shallow-water sporophytes displayed metabolic stress, reduced growth, and oxidative damage. Upon the cessation of warming, certain responses, such as a decline in nitrate uptake and net productivity, became evident in shallow-water sporophytes, implying a delay in heat-stress response. This indicates that variation in temperatures can result in more prominent effects than warming alone. The greater heat tolerance of sporophytes in deeper waters shows convincing evidence that deep portions of P. californica populations have the potential to serve as refuges from the harmful impacts of MHWs on shallow reefs.


Assuntos
Kelp , Nitratos , México , Temperatura Alta , Água , Ecossistema
8.
Braz. j. biol ; 84: e250132, 2024. tab
Artigo em Inglês | VETINDEX | ID: biblio-1374642

RESUMO

The study was designed to investigate the effect of mannan-oligosaccharide (MOS) supplementation on intestinal histomorphology, immunity against Newcastle disease virus (NDV) and productive parameters of broilers. A total of 1800, day old broiler chicks of Cobb-500 strain were selected and randomly assorted into 6 treatment groups: T1 (basal diet without antibiotics as negative control); T2 (basal diet plus antibiotics as positive control group); T3 (basal diet plus 200g/ton MOS); T4 (basal diet plus 400g/ton MOS); T5 (basal diet plus 600g/ton MOS) and T6 (basal diet plus 800g/ton MOS). Each treatment was having 6 replicates and the feed intake, body weight gain and feed conversion ratio (FCR) were recorded on weekly basis. Results showed that, MOS supplemented birds have significantly higher feed intake, weight gain and FCR (P < 0.05). Similarly, supplementation of MOS showed positive effect on villus height and crypt depth both in jejunum and ilium. Goblet cell density was unaffected by MOS addition (P < 0.05). Furthermore, birds fed with diets containing MOS, exhibited better productive performance in comparison to positive and negative control groups. In conclusion, MOS can replace antibiotic growth promoters (AGPs) as non-microbial performance-enhancing feed advocates.


O estudo foi desenhado para investigar o efeito da suplementação de mananoligossacarídeo (MOS) na histomorfologia intestinal, imunidade contra o vírus da doença de Newcastle (NDV) e parâmetros produtivos de frangos de corte. Um total de 1.800 pintos de corte de um dia da linhagem Cobb-500 foram selecionados e distribuídos aleatoriamente em 6 grupos de tratamento: T1 (dieta basal sem antibióticos como controle negativo); T2 (dieta basal mais antibióticos como grupo controle positivo); T3 (dieta basal mais 200g/ton MOS); T4 (dieta basal mais 400g/ton MOS); T5 (dieta basal mais 600g/ton MOS) e T6 (dieta basal mais 800g/ton MOS). Cada tratamento tinha 6 repetições e o consumo de ração, ganho de peso corporal e conversão alimentar foram registrados semanalmente. Os resultados mostraram que as aves suplementadas com MOS apresentam consumo de ração, ganho de peso e CA significativamente maiores (P < 0,05). Da mesma forma, a suplementação de MOS mostrou efeito positivo na altura das vilosidades e na profundidade das criptas tanto no jejuno quanto no íleo. A densidade de células caliciformes não foi afetada pela adição de MOS (P < 0,05). Além disso, as aves alimentadas com dietas contendo MOS apresentaram melhor desempenho produtivo em comparação aos grupos controle positivo e negativo. Em conclusão, o MOS pode substituir os promotores de crescimento de antibióticos (AGPs) como defensores de alimentos não microbianos que melhoram o desempenho.


Assuntos
Animais , Aves/crescimento & desenvolvimento , Vírus da Doença de Newcastle , Imunidade , Mananas/administração & dosagem , Trato Gastrointestinal
9.
Braz. j. biol ; 84: e256565, 2024. tab, graf, mapas
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1360220

RESUMO

Liupan Mountains are an important region in China in the context of forest cover and vegetation due to huge afforestation and plantation practices, which brought changes in soil physio-chemical properties, soil stocks, and soil stoichiometries are rarely been understood. The study aims to explore the distribution of soil nutrients at 1-m soil depth in the plantation forest region. The soil samples at five depth increments (0-20, 20-40, 40-60, 60-80, and 80-100 cm) were collected and analyzed for different soil physio-chemical characteristics. The results showed a significant variation in soil bulk density (BD), soil porosity, pH, cation exchange capacity (CEC), and electric conductivity (EC) values. More soil BD (1.41 g cm-3) and pH (6.97) were noticed in the deep soil layer (80-100 cm), while the highest values of porosity (60.6%), EC (0.09 mS cm-1), and CEC (32.9 c mol kg-1) were reflected in the uppermost soil layer (0-20 cm). Similarly, the highest contents of soil organic carbon (SOC), total phosphorus (TP), available phosphorus (AP), total nitrogen (TN), and available potassium (AK) were calculated in the surface soil layer (0-20 cm). With increasing soil depth increment a decreasing trend in the SOC and other nutrient concentration were found, whereas the soil total potassium (TK) produced a negative correlation with soil layer depth. The entire results produced the distribution of SOCs and TNs (stocks) at various soil depths in forestland patterns were 0→20cm > 20→40cm > 40→60cm ≥ 60→80cm ≥ 80→100 cm. Furthermore, the stoichiometric ratios of C, N, and P, the C/P, and N/P ratios showed maximum values (66.49 and 5.46) in 0-20 cm and lowest values (23.78 and 1.91) in 80-100 cm soil layer depth. Though the C/N ratio was statistically similar across the whole soil profile (0-100 cm). These results highlighted that the soil depth increments might largely be attributed to fluctuations in soil physio-chemical properties, soil stocks, and soil stoichiometries. Further study is needed to draw more conclusions on nutrient dynamics, soil stocks, and soil stoichiometry in these forests.


As montanhas de Liupan são uma região importante na China no contexto de cobertura florestal e vegetação devido às enormes práticas de florestamento e plantação, que trouxeram mudanças nas propriedades físico-químicas do solo, e estoques e estequiometrias do solo raramente são compreendidos. O estudo visa explorar a distribuição de nutrientes do solo a 1 m de profundidade do solo na região da floresta plantada. As amostras de solo em cinco incrementos de profundidade (0-20, 20-40, 40-60, 60-80 e 80-100 cm) foram coletadas e analisadas para diferentes características físico-químicas do solo. Os resultados mostraram uma variação significativa nos valores de densidade do solo (BD), porosidade do solo, pH, capacidade de troca catiônica (CEC) e condutividade elétrica (CE). Mais DB do solo (1,41 g cm-3) e pH (6,97) do solo foram observados na camada profunda do solo (80-100 cm), enquanto os maiores valores de porosidade (60,6%), CE (0,09 mS cm-1) e CEC (32,9 c mol kg-1) foram refletidos na camada superior do solo (0-20 cm). Da mesma forma, os maiores teores de carbono orgânico do solo (SOC), fósforo total (TP), fósforo disponível (AP), nitrogênio total (TN) e potássio disponível (AK) foram calculados na camada superficial do solo (0-20 cm). Com o aumento do incremento da profundidade do solo, uma tendência decrescente no SOC e na concentração de outros nutrientes foi encontrada, enquanto o potássio total do solo (TK) produziu uma correlação negativa com a profundidade da camada do solo. Todos os resultados produziram a distribuição de SOCs e TNs (estoques) em várias profundidades de solo em padrões de floresta 0 → 20cm> 20 → 40cm> 40 → 60cm ≥ 60 → 80cm ≥ 80 → 100 cm. Além disso, as relações estequiométricas de C, N e P, as relações C / P e N / P, apresentaram valores máximos (66,49 e 5,46) em 0-20 cm, e valores mais baixos (23,78 e 1,91) em solo de 80-100 cm profundidade da camada. Embora a relação C / N fosse estatisticamente semelhante em todo o perfil do solo (0-100 cm). Esses resultados destacaram que os incrementos de profundidade do solo podem ser amplamente atribuídos a flutuações nas propriedades físico-químicas do solo, estoques e estequiometrias do solo. Mais estudos são necessários para tirar conclusões adicionais sobre a dinâmica dos nutrientes, estoques de solo e estequiometria do solo nessas florestas.


Assuntos
Solo/química , Análise do Solo , Florestas , China
10.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469348

RESUMO

Abstract Liupan Mountains are an important region in China in the context of forest cover and vegetation due to huge afforestation and plantation practices, which brought changes in soil physio-chemical properties, soil stocks, and soil stoichiometries are rarely been understood. The study aims to explore the distribution of soil nutrients at 1-m soil depth in the plantation forest region. The soil samples at five depth increments (0-20, 20-40, 40-60, 60-80, and 80-100 cm) were collected and analyzed for different soil physio-chemical characteristics. The results showed a significant variation in soil bulk density (BD), soil porosity, pH, cation exchange capacity (CEC), and electric conductivity (EC) values. More soil BD (1.41 g cm-3) and pH (6.97) were noticed in the deep soil layer (80-100 cm), while the highest values of porosity (60.6%), EC (0.09 mS cm-1), and CEC (32.9 c mol kg-1) were reflected in the uppermost soil layer (0-20 cm). Similarly, the highest contents of soil organic carbon (SOC), total phosphorus (TP), available phosphorus (AP), total nitrogen (TN), and available potassium (AK) were calculated in the surface soil layer (0-20 cm). With increasing soil depth increment a decreasing trend in the SOC and other nutrient concentration were found, whereas the soil total potassium (TK) produced a negative correlation with soil layer depth. The entire results produced the distribution of SOCs and TNs (stocks) at various soil depths in forestland patterns were 020cm > 2040cm > 4060cm 6080cm 80100 cm. Furthermore, the stoichiometric ratios of C, N, and P, the C/P, and N/P ratios showed maximum values (66.49 and 5.46) in 0-20 cm and lowest values (23.78 and 1.91) in 80-100 cm soil layer depth. Though the C/N ratio was statistically similar across the whole soil profile (0-100 cm). These results highlighted that the soil depth increments might largely be attributed to fluctuations in soil physio-chemical properties, soil stocks, and soil stoichiometries. Further study is needed to draw more conclusions on nutrient dynamics, soil stocks, and soil stoichiometry in these forests.


Resumo As montanhas de Liupan são uma região importante na China no contexto de cobertura florestal e vegetação devido às enormes práticas de florestamento e plantação, que trouxeram mudanças nas propriedades físico-químicas do solo, e estoques e estequiometrias do solo raramente são compreendidos. O estudo visa explorar a distribuição de nutrientes do solo a 1 m de profundidade do solo na região da floresta plantada. As amostras de solo em cinco incrementos de profundidade (0-20, 20-40, 40-60, 60-80 e 80-100 cm) foram coletadas e analisadas para diferentes características físico-químicas do solo. Os resultados mostraram uma variação significativa nos valores de densidade do solo (BD), porosidade do solo, pH, capacidade de troca catiônica (CEC) e condutividade elétrica (CE). Mais DB do solo (1,41 g cm-3) e pH (6,97) do solo foram observados na camada profunda do solo (80-100 cm), enquanto os maiores valores de porosidade (60,6%), CE (0,09 mS cm-1) e CEC (32,9 c mol kg-1) foram refletidos na camada superior do solo (0-20 cm). Da mesma forma, os maiores teores de carbono orgânico do solo (SOC), fósforo total (TP), fósforo disponível (AP), nitrogênio total (TN) e potássio disponível (AK) foram calculados na camada superficial do solo (0-20 cm). Com o aumento do incremento da profundidade do solo, uma tendência decrescente no SOC e na concentração de outros nutrientes foi encontrada, enquanto o potássio total do solo (TK) produziu uma correlação negativa com a profundidade da camada do solo. Todos os resultados produziram a distribuição de SOCs e TNs (estoques) em várias profundidades de solo em padrões de floresta 0 20cm> 20 40cm> 40 60cm 60 80cm 80 100 cm. Além disso, as relações estequiométricas de C, N e P, as relações C / P e N / P, apresentaram valores máximos (66,49 e 5,46) em 0-20 cm, e valores mais baixos (23,78 e 1,91) em solo de 80-100 cm profundidade da camada. Embora a relação C / N fosse estatisticamente semelhante em todo o perfil do solo (0-100 cm). Esses resultados destacaram que os incrementos de profundidade do solo podem ser amplamente atribuídos a flutuações nas propriedades físico-químicas do solo, estoques e estequiometrias do solo. Mais estudos são necessários para tirar conclusões adicionais sobre a dinâmica dos nutrientes, estoques de solo e estequiometria do solo nessas florestas.

11.
CoDAS ; 36(2): e20220261, 2024. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1534251

RESUMO

ABSTRACT Purpose The inter-aural time difference (ITD) and inter-aural level difference (ILD) are important acoustic cues for horizontal localization and spatial release from masking. These cues are encoded based on inter-aural comparisons of tonotopically matched binaural inputs. Therefore, binaural coherence or the interaural spectro-temporal similarity is a pre-requisite for encoding ITD and ILD. The modulation depth of envelope is an important envelope characteristic that helps in encoding the envelope-ITD. However, inter-aural difference in modulation depth can result in reduced binaural coherence and poor representation of binaural cues as in the case with reverberation, noise and compression in cochlear implants and hearing aids. This study investigated the effect of inter-aural modulation depth difference on the ITD thresholds for an amplitude-modulated noise in normal hearing young adults. Methods An amplitude modulated high pass filtered noise with varying modulation depth differences was presented sequentially through headphones. In one ear, the modulation depth was retained at 90% and in the other ear it varied from 90% to 50%. The ITD thresholds for modulation frequencies of 8 Hz and 16 Hz were estimated as a function of the inter-aural modulation depth difference. Results The Friedman test findings revealed a statistically significant increase in the ITD threshold with an increase in the inter-aural modulation depth difference for 8 Hz and 16 Hz. Conclusion The results indicate that the inter-aural differences in the modulation depth negatively impact ITD perception for an amplitude-modulated high pass filtered noise.

12.
ACG Case Rep J ; 10(11): e01189, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37928227

RESUMO

Early gastric cancer is defined as gastric cancer confined to the mucosa or submucosa, irrespective of lymph node metastasis. Endoscopic submucosal dissection is a standard treatment of early gastric cancer. The nonextension sign consists of a protrusion of the surrounding mucosa into the lumen, resembling a trapezoidal shape. This phenomenon occurs when massive submucosal invasion by a cancer increases the thickness and rigidity of the gastric wall and may be useful to differentiate between mucosal or microinvasive submucosal and invasive submucosal cancers. Our case demonstrates the usefulness of the absence of the conventional endoscopic nonextension sign as a marker to decide the adequate approach for mucosal lesions.

13.
Environ Sci Pollut Res Int ; 30(51): 111231-111243, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37807031

RESUMO

Research on microplastics in Latin America is limited compared to a global perspective. Brazil plays a significant role in this context, as it possesses 12% of the world's freshwater reserves, constituting 53% of South America's water resources. There has been growing concern regarding the plastic pollution of the country's freshwater systems in recent years. Therefore, this study investigated the impact of plastic pollution on the Guaíba River, a significant watercourse in the southern region of Brazil that is subjected to high anthropogenic pressure. Additionally, we examined correlations between the presence of microplastics and key factors influencing their distribution in the river. Thus, freshwater was collected in seven sampling campaigns from 2019 to 2020, totaling 66 samples. The microplastics were quantified and characterized according to their color, shape, and polymeric composition. The concentration of microplastics varied between 2.9 and 53.8 items m-3, and the distribution and transport were positively influenced by the population density, precipitations, and depth of each sampling point. White-transparent color category (51%) and fragment shape (89%) were predominant among the found particles. Polyethylene (PE) and polypropylene (PP) represented 37% and 57% of the analyzed particles. The non-metric multidimensional scaling (nMDS) analysis indicated that similar contamination sources, such as domestic sewage, could influence three out of ten sampled points. Several microplastics presented the formation of cracks, with sizes smaller than 10 µm on their surface, which might indicate an erosion process, resulting in the formation of nanoplastics. The color fading observed in microplastics suggests that the particles were subjected to environmental stressors, leading to the leaching or degradation of the dye on the plastic. The results confirmed the ubiquity of microplastics in Guaíba River, highlighting the importance of improving the regulations on plastic waste disposal in the country to prevent the contamination of freshwater bodies.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos/análise , Rios , Ecossistema , Poluentes Químicos da Água/análise , Monitoramento Ambiental
14.
Rev. cuba. oftalmol ; 36(3)sept. 2023.
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1550942

RESUMO

Objetivo: Determinar las modificaciones biométricas en pacientes miopes con implante de la lente fáquica ACRIOL 128. Métodos: Se realizó un estudio transversal con 31 ojos (17 pacientes) con alta miopía tratados con implante de lente fáquica ACRIOL 128, entre septiembre 2016 y febrero 2019, los cuales tenían mediciones biométricas preoperatorias con el sistema IOL Master 3.0.2 y estabilidad refractiva posoperatoria (≤ 0,5 dioptrías) después de los tres meses del implante. Se les efectuaron las mediciones posoperatorias con el propio IOL Master 3.0.2 en modo lente fáquica y con el sistema Scheimpflug Pentacam AXL para compararlas, mediante la prueba t para datos pareados, con una significación del 95 por ciento. Resultados: La edad promedio fue de 29,82 ± 5,99 años, el 82,4 por ciento del sexo femenino. El equivalente esférico preoperatorio medio fue de -12,00 ± 4,10 dioptrías. La diferencia de longitud axial y profundidad de la cámara anterior en milímetros entre el pre- y posoperatorio fue significativa con IOL Master 3.0.2 (0,13 ± 0,33 y -0,08 ± 0,17) y Pentacam AXL (0,12 ± 0,32 y -0,10 ± 0,24), respectivamente. Sin embargo, las posoperatorias entre ambos equipos no fueron significativas (p>0,05) para estas variables, pero sí para las queratometrías. Conclusiones: El implante de la lente fáquica ACRIOL 128 modifica la medición de la longitud axial y la profundidad de la cámara anterior. El IOL Master 3.0.2 y el Pentacam AXL ofrecen mediciones de longitud axial y profundidad de cámara anterior posoperatorias similares, no así para las queratometrías(AU)


Objective: To determine the biometric modifications in myopic patients with ACRIOL 128 phakic lens implantation. Methods: A cross-sectional study was performed on 31 eyes (17 patients) with high myopia treated with ACRIOL 128 phakic lens implant, between September 2016 and February 2019, which had preoperative biometric measurements with the IOL Master 3.0.2 system and postoperative refractive stability (≤ 0.5 diopters) after three months of implantation. Postoperative measurements were performed with the IOL Master 3.0.2 in phakic lens mode and with the Scheimpflug Pentacam AXL system for comparison, using the t-test for paired data, with 95% significance. Results: The average age was 29.82 ± 5.99 years, 82.4por ciento female. The mean preoperative spherical equivalent was -12.00 ± 4.10 diopters. The difference in axial length and anterior chamber depth in millimeters between pre- and postoperative was significant with IOL Master 3.0.2 (0.13 ± 0,33 and -0.08 ± 0.17) and Pentacam AXL (0.12 ± 0.32 and -0.10 ± 0.24), respectively. However, postoperative between the two teams were not significant (p > 0.05) for these variables but significant for keratometries. Conclusions: Implantation of the ACRIOL 128 phakic lens modifies the measurement of axial length and anterior chamber depth. The IOL Master 3.0.2 and Pentacam AXL provide similar postoperative axial length and anterior chamber depth measurements, but not for keratometries(AU)


Assuntos
Humanos , Biometria/métodos , Lentes Intraoculares Fácicas
15.
Proc Biol Sci ; 290(2004): 20230543, 2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37528708

RESUMO

Medusozoa (Cnidaria) are characterized by diverse life cycles, with different semaphoronts (medusa, medusoid, fixed gonophore, polyp) representing the sexual phase and carrying the gametes. Although egg size is often considered a proxy to understand reproductive and developmental traits of medusozoans, understanding of the processes influencing egg size variation in the group under an evolutionary context is still limited. We carried out a comprehensive review of the variation of egg size in Medusozoa to test whether this variation is related to biological/sexual or environmental traits. Egg size presents a strong phylogenetic signal (λ = 0.79, K = 0.67), explaining why closely related species with different reproductive strategies and different individual sizes have similar egg sizes. However, variation in egg size is influenced by the number of eggs, depth and temperature, with larger eggs frequently present in species with few eggs (1-15), in deep-sea species and in cold-water species. Conversely, the production of small eggs among cold-water species of Staurozoa might be associated with the development of a small benthic larvae in this group. Our study reinforces that egg sizes respond to reproductive and environmental traits, although egg size is highly conserved within medusa classes.


Assuntos
Cnidários , Animais , Filogenia , Reprodução , Evolução Biológica , Água
16.
Microorganisms ; 11(7)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37512841

RESUMO

The emergence of open ocean global-scale studies provided important information about the genomics of oceanic microbial communities. Metagenomic analyses shed light on the structure of marine habitats, unraveling the biodiversity of different water masses. Many biological and environmental factors can contribute to marine organism composition, such as depth. However, much remains unknown about microbial communities' taxonomic and functional features in different water layer depths. Here, we performed a metagenomic analysis of 76 publicly available samples from the Tara Ocean Project, distributed in 8 collection stations located in tropical or subtropical regions, and sampled from three layers of depth (surface water layer-SRF, deep chlorophyll maximum layer-DCM, and mesopelagic zone-MES). The SRF and DCM depth layers are similar in abundance and diversity, while the MES layer presents greater diversity than the other layers. Diversity clustering analysis shows differences regarding the taxonomic content of samples. At the domain level, bacteria prevail in most samples, and the MES layer presents the highest proportion of archaea among all samples. Taken together, our results indicate that the depth layer influences microbial sample composition and diversity.

17.
Natal; s.n; 20 jul. 2023. 46 p. ilus, tab, graf.
Tese em Português | BBO - Odontologia | ID: biblio-1532134

RESUMO

Objetivo: Avaliar a profundidade de polimerização em diferentes espessuras da resina composta Tetric® N-Flow Bulk Fill com adição de xilitol em diferentes concentrações. Metodologia: A resina Tetric® N-Flow Bulk Fill foi misturada às concentrações do xilitol (0% [Controle], 2,5% e 5% g/g) por espatulação manual durante 1 min em uma câmara escura. Amostras cilíndricas foram confeccionadas em moldes de polimetilmetacrilato de 5 mm de diâmetro x 1 mm, 2 mm, 3 mm e 4 mm de espessura nas concentrações de xilitol propostas totalizando 12 grupos (n=3), fotoativadas por 10 s e armazenadas a 37º C por 24 h. Os espécimes foram submetidos ao teste de microdureza Vickers, sendo a profundidade de polimerização obtida por meio da razão base/topo. Foram utilizados testes não paramétricos de Kruskal Wallis para comparação das diferentes espessuras na mesma concentração e das diferentes concentrações na mesma espessura (p<0,05) através do software BioEstat 5.3. Resultados: Não houve diferença estatisticamente significativa entre as diferentes espessuras na mesma concentração, bem como entre as diferentes concentrações na mesma espessura (p=1,000). Todos os espécimes apresentaram profundidade de polimerização adequada (razão de dureza ≥80%), com exceção das amostras com 4 mm de espessura contendo 2,5 e 5% de xilitol, que apresentaram razão de dureza média de 79% e 74%, respectivamente. Conclusão: Nas condições deste estudo, pode-se concluir que a adição de xilitol a uma resina bulk fill fluida pode afetar a profundidade de polimerização em 4 mm (AU).


Objective: To evaluate the depth of cure at different thicknesses of the Tetric® NFlow Bulk Fill composite resin with the addition of xylitol at different concentrations. Materials and Methods: The Tetric™ N-Flow Bulk Fill resin was mixed with xylitol concentrations (0% [Control], 2.5%, and 5% g/g) by manual spatulation for 1 minute in a portable darkroom. Cylindrical samples were prepared in polymethyl methacrylate molds with diameters of 5 mm and thicknesses of 1 mm, 2 mm, 3 mm, and 4 mm at the proposed xylitol concentrations, totaling 12 groups (n=3), photoactivated for 10 seconds, and stored at 37°C for 24 hours. The specimens were subjected to Vickers microhardness testing, and the depth of cure was obtained by calculating the base/top ratio. Non-parametric Kruskal-Wallis tests were used to compare different thicknesses at the same concentration and different concentrations at the same thickness (p<0,05) using BioEstat 5.3 software. Results: There was no statistically significant difference between different thicknesses at the same concentration, as well as between different concentrations at the same thickness (p=1,000). All specimens exhibited adequate depth of cure (hardness ratio ≥80%), except for the samples with 4 mm thickness containing 2.5% and 5% xylitol, which showed average hardness ratios of 79% and 74%, respectively. Conclusion: Under the conditions of this study, it can be concluded that the addition of xylitol to a fluid bulk fill resin can affect the depth of cure at 4 mm (AU).


Assuntos
Teste de Materiais , Estatísticas não Paramétricas
18.
Test (Madr) ; : 1-16, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37363067

RESUMO

The lens depth of a point has been recently extended to general metric spaces, which is not the case for most depths. It is defined as the probability of being included in the intersection of two random balls centred at two random points X and Y, with the same radius d(X, Y). We prove that, on a separable and complete metric space, the level sets of the empirical lens depth based on an iid sample, converge in the Painlevé-Kuratowski sense, to its population counterpart. We also prove that, restricted to compact sets, the empirical level sets and their boundaries are consistent estimators, in Hausdorff distance, of their population counterparts, and analyse two real-life examples.

19.
J Morphol ; 284(6): e21588, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37183492

RESUMO

Penguins (Aves, Sphenisciformes) are pursuit divers that feed mainly on krill, fish, and squid. Although they are opportunistic feeders, some species are more generalists than others and many show dietary preferences toward krill and other crustaceans or fish and squid. Their diving depth seems to follow a body size pattern and relates to the type of item that they prey on. Penguins dive with their wing; hence their wing musculature is responsible for the animal maneuverability and strength while diving. In the present study, ecological traits such as diving depths and prey composition are used to explore if morphology relates to foraging habits. A geometric morphometric approach is used to quantitatively address these morphological differences in the wing apparatus of all extant penguins and a fossil species taking into consideration allometric and phylogenetic factors. Results show that morphological differences among penguins with different diets are significant and strong; groups are well separated with the greatest differences found between piscivorous and crustacivorous penguins. Dive depth has a moderate covariation with morphology and a strong correspondence with wing area. Last, Madrynornis mirandus, an exceptionally well-preserved fossil from the Miocene of Patagonia, is found to be close to the piscivorous and generalist piscivorous species. It is proposed that swimming styles correlate with specific traits of the anatomy of wing and pectoral girdle skeleton and muscles.


Assuntos
Mergulho , Spheniscidae , Animais , Spheniscidae/anatomia & histologia , Filogenia , Mergulho/fisiologia , Natação/fisiologia , Asas de Animais/fisiologia
20.
Mar Environ Res ; 188: 105996, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37104877

RESUMO

A short stretch (27°S and 30°S) along the coast of Chile is habitat for the seagrass Heterozostera nigricaulis. The seagrass is classified as endangered and grows only clonally, but there are no data on its physiology and growth. However, this information is important to gain insights into its acclimation potential and how disturbances may affect them. We therefore studied H. nigricaulis at 27° and 30°S, and determined their growth and physiology among seasons and depths over one year. Biomass was higher at 27° than at 30°S, and was always higher in summer than in autumn and winter. Increased photosynthesis supported growth in summer, and in winter carbonic anhydrase activity was in place to maintain these evergreen meadows. Our results suggest that these seagrass meadows are adapted to local conditions, which, together with their asexual reproduction, could make them more vulnerable to disturbance. Therefore, our results serve as a basis for future studies on seagrass growth dynamics, and are important for protection and management plans.


Assuntos
Zosteraceae , Chile , Zosteraceae/fisiologia , Ecossistema , Biomassa , Estações do Ano
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