Highly efficient and sensitive membrane-based concentration process allows quantification, surveillance, and sequencing of viruses in large volumes of wastewater.

Wastewater-based epidemiology is experiencing exponential development. Despite undeniable advantages compared to patient-centered approaches (cost, anonymity, survey of large populations without bias, detection of asymptomatic infected peoples…), major technical limitations persist. Among them is the low sensitivity of the current methods used for quantifying and sequencing viral genomes from wastewater. In situations of low viral circulation, during initial stages of viral emergences, or in areas experiencing heavy rains, the extremely low concentrations of viruses in wastewater may fall below the limit of detection of the current methods. The availability during crisis and the cost of the commercial kits, as well as the requirement of expensive materials such as high-speed centrifuge, can also present major blocks to the development of wastewater-based epidemiological survey, specifically in low-income countries. Thereby, highly sensitive, low cost and standardized methods are still needed, to increase the predictability of the viral emergences, to survey low-circulating viruses and to make the results from different labs comparable. Here, we outline and characterize new protocols for concentrating and quantifying SARS-CoV-2 from large volumes (500 mL-1 L) of untreated wastewater. In addition, we report that the methods are applicable for monitoring and sequencing. Our nucleic acid extraction technique (the routine C: 5 mL method) does not require sophisticated equipment such as automatons and is not reliant on commercial kits, making it readily available to a broader range of laboratories for routine epidemiological survey. Furthermore, we demonstrate the efficiency, the repeatability, and the high sensitivity of a new membrane-based concentration method (MBC: 500 mL method) for enveloped (SARS-CoV-2) and non-enveloped (F-specific RNA phages of genogroup II / FRNAPH GGII) viruses. We show that the MBC method allows the quantification and the monitoring of viruses in wastewater with a significantly improved sensitivity compared to the routine C method. In contexts of low viral circulation, we report quantifications of SARS-CoV-2 in wastewater at concentrations as low as 40 genome copies per liter. In highly diluted samples collected in wastewater treatment plants of French Guiana, we confirmed the accuracy of the MBC method compared to the estimations done with the routine C method. Finally, we demonstrate that both the routine C method processing 5 mL and the MBC method processing 500 mL of untreated wastewater are both compatible with SARS-CoV-2 sequencing. We show that the quality of the sequence is correlated with the concentration of the extracted viral genome. Of note, the quality of the sequences obtained with some MBC processed wastewater was improved by dilutions or enzyme substitutions suggesting the presence of specific enzyme inhibitors in some wastewater. To the best of our knowledge, our MBC method is one of the first efficient, sensitive, and repeatable method characterized for SARS-CoV-2 quantification and sequencing from large volumes of wastewater.

An extremely energetic cosmic ray observed by a surface detector array.

Cosmic rays are energetic charged particles from extraterrestrial sources, with the highest-energy events thought to come from extragalactic sources. Their arrival is infrequent, so detection requires instruments with large collecting areas. In this work, we report the detection of an extremely energetic particle recorded by the surface detector array of the Telescope Array experiment. We calculate the particle's energy as [Formula: see text] (~40 joules). Its arrival direction points back to a void in the large-scale structure of the Universe. Possible explanations include a large deflection by the foreground magnetic field, an unidentified source in the local extragalactic neighborhood, or an incomplete knowledge of particle physics.

Fatores de risco de aterosclerose na infância: um estudo epidemiológico / Risk factors of atherosclerosis in children: an epidemiology study

OBJETIVO - Obter um perfil dos fatores de risco coronário em uma amostra populacional pediátrica da cidade de Bento Gonçalves, RS, no período de maio/90 a junho/91. MÉTODOS - Foram estudados 1501 escolares de 6 a 16 anos incompletos, visando a detecção dos níveis séricos de colesterol total, lipoproteínas, triglicérides, bem como a avaliação da pressão arterial e da história familiar de doença cardiovascular isquêmica e obesidade. RESULTADOS - Foram detectadas 420 (27,98 'por cento') crianças com hipercolesterolemia, sendo que 75 (5 'por cento') apresentavam hipetensão arterial sistólica e 48 (3,20 'por cento') hipertensão arterial diastólica. A história familiar foi importante quando positiva, porém, sua ausência não excluia a presença de fatores de risco para a aterosclerose. A hipertrigliceridemia foi encontrada em 136 (9,06 'por cento') escolares e a LDL-colesterol elevada em 155 (10,33 'por cento'), mostrando forte associação com hipercolesterolemia. Apresentaram índice de massa corporal acima de percentil 95, não mostrando uma maior prevalência de hipercolesterolemia, 111 crianças. CONCLUSÄO - Os fatores de risco para a aterosclerose estão presentes na infância e deveriam ser pesquisados independentemente do nível socioeconômico, da história familiar, da idade e do sexo, devendo o pediatra ser um dos responsáveis por esta investigação.

[Risk factors for atherosclerosis in children: an epidemiologic study]. / Factores de risco de aterosclerose na infância. Um estudo epidemiológico.

PURPOSE: To obtain a profile of risk factors for coronary atherosclerosis in a pediatric population from Bento Gonçalves, Rio Grande do Sul, from May 1990 to June 1991. METHODS: One thousand five hundred and one children with ages from 6 to 15 years were studied to assess serum cholesterol levels and their association with other risk factors, such as arterial hypertension, obesity and family history of cardiovascular disease. RESULTS: Four hundred and twenty (27.98%) children showed cholesterol levels over 180 mg%; 75 (5%) had systolic hypertension and 48 (3.20%) diastolic hypertension. The family history was important to search for risk factors such as hypercholesterolemia, but did not exclude risk factors when negative. One hundred and thirty six (9.06%) children showed hipetriglyceridemia; 155 (10.33%) presented LDL-cholesterol above 130 mg% and showed a strong association with hypercholesterolemia. Obesity was present in 111 children, but none showed a major prevalence of hypercholesterolemia. CONCLUSION: Risk factors for atherosclerosis are present in children and their search should be performed, independent of family income, family history, age and sex. The pediatrician must have a significant role in this setting.