A Survey on the Effect of the Chemical Composition on the Thermal, Physical, Mechanical, and Dynamic Mechanical Thermal Analysis of Three Brazilian Wood Species.

Wood is a versatile material extensively utilized across industries due to its low density, favorable mechanical properties, and environmental benefits. However, despite considerable research, the diversity in species with varying compositions and properties remains insufficiently explored, particularly for native woods. A deeper understanding of these differences is crucial for optimizing their industrial applications. This study investigated the composition, tensile strength, flexural strength, Young's modulus, bending stiffness and elongation at break, thermal behavior, and viscoelastic properties of three Brazilian native wood species: Araucaria angustifolia (ARA), Dipterix odorata (DOD), and Tabeuia ochracea (TOC). The density of these woods showed a linear correlation with mechanical properties such as Young's modulus (0.9) and flexural modulus (0.9). The research revealed a linear correlation between the woods' density and mechanical properties, with lignin content emerging as a key determinant of thermal stability. This study highlights the importance of understanding wood species' composition and physical properties, and provides valuable insights into their behavior.

A method to promote safe cycling powered by large language models and AI agents.

This paper presents a novel information generation methodology to support safer cycling patterns in urban environments, leveraging for that Large Language Models (LLMs), AI-based agents, and open geospatial data. By processing multiple files containing previously computed urban risk levels and existing mobility infrastructure, which are generated by exploiting open data sources, our method exploits multi-layer data preprocessing procedures and prompt engineering to create easy-to-use, user-friendly assistive systems that are able to provide useful information concerning cycling safety. Through a well-defined processing pipeline based on Data Ingestion and Preparation, Agents Orchestration, and Decision Execution methodological steps, our method shows how to integrate open-source tools and datasets, ensuring reproducibility and accessibility for urban planners and cyclists. Moreover, an AI agent is also provided, which fully implements our method and acts as a proof-of-concept implementation. This paper demonstrates the effectiveness of our method in enhancing cycling safety and urban mobility planning.•A novel method that combines LLMs and AI agents is defined to enhance the processing of multi-domain open geospatial data, potentially promoting cycling safety.•It integrates urban risk data and cycling infrastructure for a more comprehensive understanding of cycling resources, which become accessible by textual or audio prompts.

Visceral crisis in metastatic breast cancer: an old concept with new perspectives.

Visceral Crisis (VC) in breast cancer is a critical scenario when the burden of metastatic disease results in rapid deterioration of organ functions. There are no widely accepted objective clinical criteria for the definition of VC, and different studies have reported diverse clinical conditions such as visceral crises. Diagnosis of VC is associated with a dismal prognosis and the management of this condition is currently based on limited retrospective evidence and expert opinions. International guidelines have recommended cytotoxic polychemotherapy in the management of VC, to achieve rapid symptomatic control and preserve organ function. Nevertheless, in the case of hormone receptor-positive breast cancer, the role of chemotherapy as the treatment of choice for VC has been recently questioned, since endocrine therapy plus CDK4/6 inhibitors yielded similar response rates, with better quality of life. For HER2-positive and triple-negative breast cancer, combined chemotherapy (plus HER2-directed therapy for HER2-positive) remains a standard option for VC, but novel effective drugs such as antibody-drug conjugates are emerging and their role in the VC context shall soon be elucidated. This review aims to critically discuss the definition, prognosis, management, and future directions regarding the visceral crisis in metastatic breast cancer.

Monitoramento de vetores do gênero Aedes durante o inverno no município de Barbacena, Minas Gerais, Brasil ­ 2018 / Monitoring of vectors of the genus Aedes during winter in the municipality of Barbacena, Minas Gerais, Brazil ‒ 2018

Objetivo: estimar a oviposição e distribuição espacial de vetores Aedes durante a estação de inverno e correlacionar essas estimativas com dados climáticos do mesmo período. Métodos: estudo de campo conduzido no município de Barbacena-MG, em 2018. O monitoramento, a coleta de ovos e a estimativa de índices estegômicos de vetores Aedes foram obtidos por meio de ovitrampas. Os Índices de Densidade de Ovos (IDO) e de Positividade de Ovitrampas (IPO%) foram estimados conforme estações climáticas e semanas epidemiológicas. A correlação entre parâmetros meteorológicos (temperatura/pluviometria) e índices estegômicos (IDO/IPO) foi determinada pelo coeficiente de Spearman. Resultados: um total de 1.080 ovitrampas, instaladas em 39 bairros, foi analisado durante 10 semanas epidemiológicas, fornecendo um total de 970 ovos. Nas estações de outono, inverno e primavera, foram obtidos, respectivamente, 421, 470 e 70 ovos. Durante o outono, houve variação do IDO entre 14,2 e 34,2. O IPO manteve-se constante em 4,5%. Durante o inverno, houve variação do IDO entre 0,00 e 47,50 e do IPO entre 0,00% e 8,25%. Houve correlação negativa significativa tanto entre aumento da precipitação mensal e diminuição do número de ovos coletados (rho=-0.673) quanto entre aumento da precipitação mensal e diminuição do IPO (rho=-0.612). O valor geral do IDO e do IPO nas 10 semanas foi, respectivamente, 22,04 e 4,17% e, na estação de inverno, foi, respectivamente, 23,50 e 3,73%. Conclusão: os achados corroboram a presença de ovos e vetores do gênero Aedes mesmo em condições climáticas adversas para essas espécies e sustentam ações de manejo sanitário durante todo o ano.

Objective: to estimate oviposition and spatial distribution of Aedes vectors during the winter season and correlate these estimates with climate data from the same period. Methods: field study conducted in the municipality of Barbacena-MG in 2018. Monitoring, egg collection, and estimation of stegomic indices of Aedes were obtained using ovitraps. The Indices of Egg Density (EDI) and Positive Ovitrap (POI%) were estimated according to climatic seasons and epidemiological weeks. The correlation between meteorological parameters (temperature/rainfall) and stegomic indices (EDI/POI) was determined by the Spearman coefficient. Results: a total of 1,080 ovitraps installed in 39 neighborhoods were analyzed during ten (10) epidemiological weeks, providing a total of 970 eggs. In the autumn, winter, and spring seasons, 421, 470, and 70 eggs were obtained, respectively. During the autumn, there was a variation in EDI between 14.2­34.2. The POI remained constant at 4.5%. During the winter, the EDI varied between 0.00­47.50, and the POI varied between 0.00%­8.25%. There was a significant negative correlation, respectively, between an increase in monthly precipitation and a decrease in the number of eggs collected (rho=-0.673) and between an increase in monthly precipitation and a decrease in POI (rho=-0.612). The overall value of EDI and POI in the ten (10) weeks was 22.04 and 4.17%, and in the winter season, they were 23.50 and 3.73%, respectively. Conclusion: the findings corroborate the presence of eggs and vectors of the genus Aedes even in adverse climatic conditions for these species and support health management actions throughout the year.

Visceral crisis in metastatic breast cancer: an old concept with new perspectives

Abstract Visceral Crisis (VC) in breast cancer is a critical scenario when the burden of metastatic disease results in rapid deterioration of organ functions. There are no widely accepted objective clinical criteria for the definition of VC, and different studies have reported diverse clinical conditions such as visceral crises. Diagnosis of VC is associated with a dismal prognosis and the management of this condition is currently based on limited retrospective evidence and expert opinions. International guidelines have recommended cytotoxic polychemotherapy in the management of VC, to achieve rapid symptomatic control and preserve organ function. Nevertheless, in the case of hormone receptor-positive breast cancer, the role of chemotherapy as the treatment of choice for VC has been recently questioned, since endocrine therapy plus CDK4/6 inhibitors yielded similar response rates, with better quality of life. For HER2-positive and triple-negative breast cancer, combined chemotherapy (plus HER2-directed therapy for HER2-positive) remains a standard option for VC, but novel effective drugs such as antibody-drug conjugates are emerging and their role in the VC context shall soon be elucidated. This review aims to critically discuss the definition, prognosis, management, and future directions regarding the visceral crisis in metastatic breast cancer.

Evaluation of Thermal Decomposition Kinetics of Poly (Lactic Acid)/Ethylene Elastomer (EE) Blends.

The influences of ethylene-based elastomer (EE) and the compatibilizer agent ethylene-butyl acrylate-glycidyl methacrylate (EBAGMA) on the thermal degradation of PLA/EE blends were evaluated by the thermal degradation kinetics and thermodynamic parameters using thermogravimetry. The presence of EE and EBAGMA synergistically improved the PLA thermal stability. The temperature of 10% of mass loss (T10%) of PLA was around 365 °C, while in the compatibilized PLA/EE blend, this property increased to 370 °C. The PLA average activation energy (Ea¯) reduced in the PLA/EE blend (from 96 kJ/mol to 78 kJ/mol), while the presence of EBAGMA in the PLA/EE blend increased the Ea¯ due to a better blend compatibilization. The solid-state thermal degradation of the PLA and PLA/EE blends was classified as a D-type degradation mechanism. In general, the addition of EE increased the thermodynamic parameters when compared to PLA and the compatibilized blend due to the increase in the collision rate between the components over the thermal decomposition.

Assessing the influence of sewage outfalls on seagrass meadows using nitrogen isotopes.

Untreated sewage discharged increases the nutrient loads and changes ecosystem functions. It increases the values of the nitrogen isotopic signature (δ15N) of primary producers such as seagrasses. Itaparica Island (Bahia, Brazil) has undergone extensive urbanization over 50 years. Most of the island has no sewage treatment, and a bridge's construction could increase its population ten times. We evaluated the effects of sewage inputs on the δ15N of seagrass (Halodule wrightii) across Itaparica Island in 14 areas of the island with different degrees of urbanization. Average values of δ15N ranged from -3.95 ‰ (±1.04 SD) to 2.73 ‰ (±1.61). The highest human occupation site also has the highest mean value of δ15N, and seagrass shoot density. The significant correlation (p < 0.05) between δ15N values and shoot density may indicate a possible anthropogenic pressure impacting meadow abundance. Despite a positive correlation, increased anthropogenic nutrient supply can support algae growth and harm seagrass ecosystems.

Conhecimentos de acadêmicos de enfermagem sobre a infecção pelo papilomavírus humano / Knowledge Of Nursing StudentsAbout The Human Papillomavirus Infection

Objetivo: objetivo identificar o conhecimento dos acadêmicos de enfermagem relacionados à temática do Papiloma Vírus Humano. Método: Trata-se de um estudo descritivo com abordagem quantitativa, desenvolvida em uma faculdade de cunho privado. Participaram da pesquisa ocorrida no período de setembro de 2022 um total de156 acadêmicos de enfermagem. Resultados: O estudo demonstrou que 70,5% (110) dos alunos são mulheres, fato este que demonstra ser uma realidade na profissão. Diante dos questionamentos sobre Papiloma Vírus Humano, 94,9% (148) afirmaram que o Papiloma Vírus Humano é uma infecção sexualmente transmissível, ainda assim afirmaram em sua maioria que as mulheres são público alvo do vírus, como também, confirmam que é através do contato com lesões 42,3% (107) que o vírus é transmitido. Conclusão: Dessa forma, após avaliações dos dados obtidos foi possível notar que os acadêmicos ao se matricularem na faculdade já possuem conhecimentos empíricos e ao passarem pelas disciplinas na universidade esse conhecimento tornam-secientíficos. (AU)

Objective: To identify the knowledge of nursing students related to the Human Papilloma Virus theme. Method: This is a descriptive study with a quantitative approach, developed in a private college. A total of156 nursing students participated in the research that occurred in the period of September 2022. Results: The study showed that 70.5% (110) of the students are women, a fact that demonstrates that this is a reality in the profession. When asked about Human Papilloma Virus, 94.9% (148) said that the Human Papilloma Virus is a sexually transmitted infection, yet they mostly said that women are the target of the virus, as well as confirm that it is through contact with lesions that 42.3% (107) that the virus is transmitted. Conclusion: Thus, after evaluating the data obtained, it was possible to notice that when the students enrolled in college they already have empirical knowledge, and by going through the disciplines at the university this knowledge becomes scientific.(AU)

Objetivo: Identificar los conocimientos de los estudiantes de enfermería relacionados con el tema Virus del Papiloma Humano. Método: Se trata de un estudio descriptivo con abordaje cuantitativo, desarrollado en una facultad privada. Participaram da pesquisa ocorrida no período de setembro de 2022 um total de156 acadêmicos de enfermagem. Resultados: El estudio mostró que el 70,5% (110) de los estudiantes son mujeres, un hecho que demuestra ser una realidad en la profesión. Frente a las preguntas sobre el Virus del Papiloma Humano, 94,9% (148) dijeron que el Virus del Papiloma Humano es una infección de transmisión sexual, sin embargo, en su mayoría dijeron que las mujeres son el público objetivo del virus, así como confirmar que es a través del contacto con las lesiones 42,3% (107) que el virus se transmite. Conclusión: Así, después de evaluar los datos obtenidos, fue posible notar que los alumnos matriculados en la facultad ya poseen conocimientos empíricos y al pasar por las disciplinas en la universidad estos conocimientos se tornan científicos.(AU)

Ultrasound Histotripsy on a Viable Perfused Whole Porcine Liver: Histological Aspects, Including 3D Reconstruction of the Histotripsy Site.

Non-invasive therapeutic-focused ultrasound (US) can be used for the mechanical dissociation of tissue and is described as histotripsy. We have performed US histotripsy in viable perfused ex vivo porcine livers as a step in the development of a novel approach to hepatocyte cell transplantation. The histotripsy nidus was created with a 2 MHz single-element focused US transducer, producing 50 pulses of 10 ms duration, with peak positive and negative pressure values of P+ = 77.7 MPa and P- = -13.7 MPaat focus, respectively, and a duty cycle of 1%. Here, we present the histological analysis, including 3D reconstruction of histotripsy sites. Five whole porcine livers were retrieved fresh from the abattoir using human transplant retrieval and cold static preservation techniques and were then perfused using an organ preservation circuit. Whilst under perfusion, histotripsy was performed to randomly selected sites on the live. Fifteen lesional sites were formalin-fixed and paraffin-embedded. Sections were stained with Haematoxylin and Eosin and picro-Sirius red, and they were also stained for reticulin. Additionally, two lesion sites were used for 3D reconstruction. The core of the typical lesion consisted of eosinophilic material associated with reticulin loss, collagen damage including loss of birefringence to fibrous septa, and perilesional portal tracts, including large portal vein branches, but intact peri-lesional hepatic plates. The 3D reconstruction of two histotripsy sites was successful and confirmed the feasibility of this approach to investigate the effects of histotripsy on tissue in detail.

Liver Ultrasound Histotripsy: Novel Analysis of the Histotripsy Site Cell Constituents with Implications for Histotripsy Application in Cell Transplantation and Cancer Therapy.

Introduction: Allogenic hepatocyte transplantation is an attractive alternative to whole-organ transplantation, particularly for the treatment of metabolic disorders and acute liver failure. However, the shortage of human donor organs for cell isolation, the low cell yield from decellularisation regimes, and low engraftment rates from portal administration of donor cells have restricted its clinical application. Using ultrasound histotripsy to provide a nidus in the liver for direct cell transplantation offers a new approach to overcoming key limitations in current cell therapy. We have analysed the liver cavity constituents to assess their potential as a site for cell delivery and implantation. Methods: Using human organ retrieval techniques, pig livers were collected from the abattoir and transported in ice-cold storage to the laboratory. Following 2 h of cold storage, the livers were flushed with organ preservation solution and placed on an organ perfusion circuit to maintain viability. Organs were perfused with Soltran™ organ preservation solution via the portal vein at a temperature of 24-30 °C. The perfusion circuit was oxygenated through equilibration with room air. Perfused livers (n=5) were subjected to ultrasound histotripsy, producing a total of 130 lesions. Lesions were generated by applying 50 pulses at 1 Hz pulse repetition frequency and 1% duty cycle using a single element 2 MHz bowl-shaped transducer (Sonic Concepts, H-148). Following histotripsy, a focal liver lesion was produced, which had a liquid centre. The fluid from each lesion was aspirated and cultured in medium (RPMI) at 37 °C in an incubator. Cell cultures were analysed at 1 and 7 days for cell viability and a live-dead assay was performed. The histotripsy sites were excised following aspiration and H&E staining was used to characterise the liver lesions. Cell morphology was determined by histology. Results: Histotripsy created a subcapsular lesion (~5 mm below the liver capsule; size ranging from 3 to 5 mm), which contained a suspension of cells. On average, 61×104 cells per mL were isolated. Hepatocytes were present in the aspirate, were viable at 24 h post isolation and remained viable in culture for up to 1 week, as determined by phalloidin/DAPI cell viability stains. Cultures up to 21 days revealed metabolically active live hepatocyte. Live-dead assays confirmed hepatocyte viability at 1 week (Day 1: 12% to Day 7: 45% live cells; p < 0.0001), which retained metabolic activity and morphology, confirmed on assay and microscopy. Cell Titre-GloTM showed a peak metabolic activity at 1 week (average luminescence 24.6 RLU; p < 0.0001) post-culture compared with the control (culture medium alone), reduced to 1/3 of peak level (7.85 RLU) by day 21. Conclusions: Histotripsy of the liver allows isolation and culture of hepatocytes with a high rate of viability after 1 week in culture. Reproducing these findings using human livers may lead to wide clinical applications in cell therapy.

Doege-Potter syndrome associated to metastatic solitary fibrous tumor.

Solitary fibrous tumor (SFT) is a rare fibroblastic mesenchymal neoplasm with an estimated annual incidence of 0.35 per 100,000 individuals. Doege-Potter syndrome is a paraneoplastic syndrome related to solitary fibrous tumor clinically characterized by hypoglycemia, occurring in less than 5% of cases. Herein, we report a case of metastatic SFT associated with recurrent severe hypoglycemia. A 43-year-old male with a noncontributory medical history presented with a painless and progressive growing mass in the right thigh. The histological evaluation rendered the diagnosis of SFT, and tumor resection was performed. One year after the operation, on the oncological follow-up, he was admitted to the emergency unit, manifesting an early-morning seizure associated with a severe hypoglycemia. The laboratory findings of non-islet cell tumor hypoglycemia (NICTH) in the background of a relapsed metastatic solitary fibrous tumor were consistent with the diagnosis of Doege-Potter syndrome. Hepatic embolization associated with oral glucocorticoid was an efficient palliative treatment to control the hypoglycemic crisis and allow hospital discharge.

Mechanisms of nuclei growth in ultrasound bubble nucleation.

This paper interrogates the intersections between bubble dynamics and classical nucleation theory (CNT) towards constructing a model that describes intermediary nucleation events between the extrema of cavitation and boiling. We employ Zeldovich's hydrodynamic approach to obtain a description of bubble nuclei that grow simultaneously via hydrodynamic excitation by the acoustic field and vapour transport. By quantifying the relative dominance of both mechanisms, it is then possible to discern the extent to which viscosity, inertia, surface tension and vapour transport shape the growth of bubble nuclei through non-dimensional numbers that naturally arise within the theory. The first non-dimensional number Φ12/Φ2 is analogous to the Laplace number, representing the balance between surface tension and inertial constraints to viscous effects. The second non-dimensional number δ represents how enthalpy transport into the bubble can reduce nucleation rates by cooling the surrounding liquid. This formulation adds to the current understanding of ultrasound bubble nucleation by accounting for bubble dynamics during nucleation, quantifying the physical distinctions between "boiling" and "cavitation" bubbles through non-dimensional parameters, and outlining the characteristic timescales of nucleation according to the growth mechanism of bubbles throughout the histotripsy temperature range. We observed in our simulations that viscous effects control the process of ultrasound nucleation in water-like media throughout the 0-120 °C temperature range, although this dominance decreases with increasing temperatures. Enthalpy transport was found to reduce nucleation rates for increasing temperatures. This effect becomes significant at temperatures above 30 °C and favours the creation of fewer nuclei that are larger in size. Conversely, negligible enthalpy transport at lower temperatures can enable the nucleation of dense clusters of small nuclei, such as cavitation clouds. We find that nuclei growth as modelled by the Rayleigh-Plesset equation occurs over shorter timescales than as modelled by vapour-dominated growth. This suggests that the first stage of bubble nuclei growth is hydrodynamic, and vapour transport effects can only be observed over longer timescales. Finally, we propose that this framework can be used for comparison between different experiments in bubble nucleation, towards standardisation and dosimetry of protocols.

Doege-Potter syndrome associated to metastatic solitary fibrous tumor

ABSTRACT Solitary fibrous tumor (SFT) is a rare fibroblastic mesenchymal neoplasm with an estimated annual incidence of 0.35 per 100,000 individuals. Doege-Potter syndrome is a paraneoplastic syndrome related to solitary fibrous tumor clinically characterized by hypoglycemia, occurring in less than 5% of cases. Herein, we report a case of metastatic SFT associated with recurrent severe hypoglycemia. A 43-year-old male with a noncontributory medical history presented with a painless and progressive growing mass in the right thigh. The histological evaluation rendered the diagnosis of SFT, and tumor resection was performed. One year after the operation, on the oncological follow-up, he was admitted to the emergency unit, manifesting an early-morning seizure associated with a severe hypoglycemia. The laboratory findings of non-islet cell tumor hypoglycemia (NICTH) in the background of a relapsed metastatic solitary fibrous tumor were consistent with the diagnosis of Doege-Potter syndrome. Hepatic embolization associated with oral glucocorticoid was an efficient palliative treatment to control the hypoglycemic crisis and allow hospital discharge.

Estimating underdiagnosis of COVID-19 with nowcasting and machine learning.

OBJECTIVE: To analyze the underdiagnosis of COVID-19 through nowcasting with machine learning in a Southern Brazilian capital city. METHODS: Observational ecological design and data from 3916 notified cases of COVID-19 from April 14th to June 2nd, 2020 in Florianópolis, Brazil. A machine-learning algorithm was used to classify cases that had no diagnosis, producing the nowcast. To analyze the underdiagnosis, the difference between data without nowcasting and the median of the nowcasted projections for the entire period and for the six days from the date of onset of symptoms were compared. RESULTS: The number of new cases throughout the entire period without nowcasting was 389. With nowcasting, it was 694 (95%CI 496-897). During the six-day period, the number without nowcasting was 19 and 104 (95%CI 60-142) with nowcasting. The underdiagnosis was 37.29% in the entire period and 81.73% in the six-day period. The underdiagnosis was more critical in the six days from the date of onset of symptoms to diagnosis before the data collection than in the entire period. CONCLUSION: The use of nowcasting with machine learning techniques can help to estimate the number of new disease cases.

Modeling the Physics of Bubble Nucleation in Histotripsy.

This work aims to establish a theoretical framework for the modeling of bubble nucleation in histotripsy. A phenomenological version of the classical nucleation theory was parametrized with histotripsy experimental data, fitting a temperature-dependent activity factor that harmonizes theoretical predictions and experimental data for bubble nucleation at both high and low temperatures. Simulations of histotripsy pressure and temperature fields are then used in order to understand spatial and temporal properties of bubble nucleation at varying sonication conditions. This modeling framework offers a thermodynamic understanding on the role of the ultrasound frequency, waveforms, peak focal pressures, and duty cycle on patterns of ultrasound-induced bubble nucleation. It was found that at temperatures lower than 50 °C, nucleation rates are more appreciable at very large negative pressures such as -30 MPa. For focal peak-negative pressures of -15 MPa, characteristic of boiling histotripsy, nucleation rates grow by 20 orders of magnitude in the temperature interval 60 °C-100 °C.

Treating corneal neovascularization using a combination of anti-VEGF injection and argon laser photocoagulation application - case report.

The present study aimed to demonstrate the possibility to treat corneal neovascularization using the combination of anti-VEGF injection and argon laser photocoagulation.

The interaction of shockwaves with a vapour bubble in boiling histotripsy: The shock scattering effect.

Boiling histotripsy is a High Intensity Focused Ultrasound (HIFU) technique which uses a number of short pulses with high acoustic pressures at the HIFU focus to induce mechanical tissue fractionation. In boiling histotripsy, two different types of acoustic cavitation contribute towards mechanical tissue destruction: a boiling vapour bubble and cavitation clouds. An understanding of the mechanisms underpinning these phenomena and their dynamics is therefore paramount to predicting and controlling the overall size of a lesion produced for a given boiling histotripsy exposure condition. A number of studies have shown the effects of shockwave heating in generating a boiling bubble at the HIFU focus and have studied its dynamics under boiling histotripsy insonation. However, not much is known about the subsequent production of cavitation clouds that form between the HIFU transducer and the boiling bubble. The main objective of the present study is to examine what causes this bubble cluster formation after the generation of a boiling vapour bubble. A numerical simulation of 2D nonlinear wave propagation with the presence of a bubble at the focus of a HIFU field was performed using the k-Wave MATLAB toolbox for time domain ultrasound simulations, which numerically solves the generalised Westervelt equation. The numerical results clearly demonstrate the appearance of the constructive interference of a backscattered shockwave by a bubble with incoming incident shockwaves. This interaction (i.e., the reflected and inverted peak positive phase from the bubble with the incoming incident rarefactional phase) can eventually induce a greater peak negative pressure field compared to that without the bubble at the HIFU focus. In addition, the backscattered peak negative pressure magnitude gradually increased from 17.4 MPa to 31.6 MPa when increasing the bubble size from 0.2 mm to 1.5 mm. The latter value is above the intrinsic cavitation threshold of -28 MPa in soft tissue. Our results suggest that the formation of a cavitation cloud in boiling histotripsy is a threshold effect which primarily depends (a) the size and location of a boiling bubble, and (b) the sum of the incident field and that scattered by a bubble.

Systematic review of the role of high intensity focused ultrasound (HIFU) in treating malignant lesions of the hepatobiliary system.

BACKGROUND: High Intensity Focused Ultrasound (HIFU) is an emerging non-invasive, targeted treatment of malignancy. The aim of this review was to assess the efficacy, safety and optimal technical parameters of HIFU to treat malignant lesions of the hepatobiliary system. METHODS: A systematic search of the English literature was performed until March 2020, interrogating Pubmed, Embase and Cochrane Library databases. The following key-words were input in various combinations: 'HIFU', 'High intensity focussed ultrasound', 'Hepatobiliary', 'Liver', 'Cancer' and 'Carcinoma'. Extracted content included: Application type, Exposure parameters, Patient demographics, and Treatment outcomes. RESULTS: Twenty-four articles reported on the clinical use of HIFU in 940 individuals to treat malignant liver lesions. Twenty-one studies detailed the use of HIFU to treat hepatocellular carcinoma only. Mean tumour size was 5.1 cm. Across all studies, HIFU resulted in complete tumour ablation in 55% of patients. Data on technical parameters and the procedural structure was very heterogeneous. Ten studies (n = 537 (57%) patients) described the use of HIFU alongside other modalities including TACE, RFA and PEI; 66% of which resulted in complete tumour ablation. Most common complications were skin burns (15%), local pain (5%) and fever (2%). CONCLUSION: HIFU has demonstrated benefit as a treatment modality for malignant lesions of the hepatobiliary system. Combining HIFU with other ablative therapies, particularly TACE, increases the efficacy without increasing complications. Future human clinical studies are required to determine the optimal treatment parameters, better define outcomes and explore the risks and benefits of combination therapies.

Estimating underdiagnosis of COVID-19 with nowcasting and machine learning / Estimativa do subdiagnóstico de COVID-19 utilizando machine learning e nowcasting

ABSTRACT: Objective: To analyze the underdiagnosis of COVID-19 through nowcasting with machine learning in a Southern Brazilian capital city. Methods: Observational ecological design and data from 3916 notified cases of COVID-19 from April 14th to June 2nd, 2020 in Florianópolis, Brazil. A machine-learning algorithm was used to classify cases that had no diagnosis, producing the nowcast. To analyze the underdiagnosis, the difference between data without nowcasting and the median of the nowcasted projections for the entire period and for the six days from the date of onset of symptoms were compared. Results: The number of new cases throughout the entire period without nowcasting was 389. With nowcasting, it was 694 (95%CI 496-897). During the six-day period, the number without nowcasting was 19 and 104 (95%CI 60-142) with nowcasting. The underdiagnosis was 37.29% in the entire period and 81.73% in the six-day period. The underdiagnosis was more critical in the six days from the date of onset of symptoms to diagnosis before the data collection than in the entire period. Conclusion: The use of nowcasting with machine learning techniques can help to estimate the number of new disease cases.

RESUMO: Objetivo: Analisar o subdiagnóstico da COVID-19 por meio de nowcasting com machine learning em uma capital do sul do Brasil. Métodos: Estudo ecológico observacional utilizando dados de 3.916 casos notificados de COVID-19 de 14 de abril a 2 de junho de 2020 em Florianópolis, Brasil. O algoritmo de machine learning foi usado para classificar os casos que ainda não tinham diagnóstico, produzindo o nowcasting. Para analisar o subdiagnóstico, foi comparada a diferença entre os dados sem nowcasting e a mediana das projeções com nowcasting para todo o período e para os seis dias a partir da data de início dos sintomas. Resultados: O número de novos casos sem nowcasting durante todo o período foi de 389, com nowcasting foi de 694 (IC95% 496-897). No período de seis dias, o número sem nowcasting foi de 19 e 104 (IC95% 60-142) com nowcasting. O subdiagnóstico foi de 37,29% em todo o período e 81,73% no período de seis dias. O subdiagnóstico foi mais crítico em seis dias, desde a data do início dos sintomas até o diagnóstico antes da coleta de dados, do que em todo o período. Conclusão: O uso de nowcasting com técnicas de machine learning pode ajudar a estimar o número de novos casos da doença.

Bridging the mental health treatment gap: effects of a collaborative care intervention (matrix support) in the detection and treatment of mental disorders in a Brazilian city.

OBJECTIVE: To analyse temporal trends in diagnosis and treatment of mental disorders in primary care following implementation of a collaborative care intervention (matrix support). DESIGN: Dynamic cohort design with retrospective time-series analysis. Structured secondary data on medical visits to general practitioners of all study clinics were extracted from the municipal electronic records database. Annual changes in the odds of mental disorders diagnoses and antidepressants prescriptions were estimated by multiple logistic regression at visit and patient-year levels with diagnoses or prescriptions as outcomes. Annual changes during two distinct stages of the intervention (stage 1 when it was restricted to mental health (2005-2009), and stage 2 when it was expanded to other areas (2010-2015)) were compared by adding year-period interaction terms to each model. SETTING: 49 primary care clinics in the city of Florianópolis, Brazil. PARTICIPANTS: All adults attending primary care clinics of the study setting between 2005 and 2015. RESULTS: 3 131 983 visits representing 322 100 patients were analysed. At visit level, the odds of mental disorder diagnosis increased by 13% per year during stage 1 (OR 1.13, 95% CI 1.11 to 1.14, p<0.001) and decreased by 5% thereafter (OR 0.95, 95% CI 0.94 to 0.95, p<0.001). The odds of incident mental disorder diagnoses decreased by 1% per year during stage 1 (OR 0.99, 95% CI 0.98 to 1.00, p=0.012) and decreased by 7% per year during stage 2 (OR 0.93, 95% CI 0.92 to 0.93, p<0.001). The odds of antidepressant prescriptions in patients with a mental disorder diagnosis increased by 7% per year during stage 1 (OR 1.07, 95% CI 1.05 to 1.20, p<0.001); this was driven by selective serotonin reuptake inhibitor prescriptions which increased 14% per year during stage 1 (OR 1.14, 95% CI 1.12 to 1.18, p<0.001) and 9% during stage 2 (OR 1.09, 95% CI 1.08 to 1.10, p<0.001). The odds of incident antidepressant prescriptions did not increase during stage 1 (OR 1.00, 95% CI 0.97 to 1.02, p=0.665) and increased by 3% during stage 2 (OR 1.03, 95% CI 1.00 to 1.04, p<0.001). Changes per year were all significantly greater during stage 1 than stage 2 (p values for interaction terms <0.05), except for antidepressant prescriptions during visits (p=0.172). CONCLUSION: The matrix support intervention may increase diagnosis and treatment of mental disorders when inter-professional collaboration is adequately supported. Competing demands to the primary care teams can subsequently reduce these effects. Future studies should assess clinical outcomes and identify active components and factors associated with successful implementation.