Unraveling the genetic complexity of a cultivated breeding population of "yerba mate" (Ilex paraguariensis St. Hil.).

We report the first comprehensive multilocus molecular characterization of cultivated Ilex paraguariensis plants belonging to a breeding program. Using nuclear and homologous chloroplastidic molecular markers, we have genotyped 158 plants from four plantation sites. Analyses of the nuclear data (187 variable dominant loci) allowed detecting high diversity (0.569), the occurrence of four distinct genetic clusters, and a low but significant differentiation among sites. Additionally, 20 chloroplastidic alleles were identified applying five microsatellite polymorphic markers, and a high chloroplastidic diversity was recognized (0.505); two haplogroups were distinguished amongst the 63 haplotypes detected. Our results from both nuclear and plastidic markers indicate that most genetic variation reside within plantations sites (≥ 95%), and that these plantations were established on highly variable materials (either as seeds or plantlets) derived from, at least, 63 maternal lineages. Moreover, our study suggests that the genetic structure within each plantation site was most likely shaped by past admixture favored by farmers´ practices during the establishment of each plantation. Also, subsequent constraints in gene flow and/or a low level of shared polymorphism among plantations could have contributed to current structure.

Impact of the COVID-19 pandemic on cataract surgeries in Brazil: A retrospective study.

PURPOSE: This study aimed to describe the behavioral patterns of data on cataract surgery performed in the Brazilian public health system before, during, and after the COVID-19 outbreak and estimate the setbacks generated by the pandemic to guide public policies. MATERIALS AND METHODS: This was an observational, longitudinal, and descriptive epidemiological study based on data retrieved from the public health system's databases of cataract surgeries performed each year and in each region from 2015 to 2022. RESULT: In Brazil, compared with the average of the 5-years preceding the pandemic, a 23 % reduction in the number of cataract surgeries was observed in 2020, followed by a 21 % increase in 2021, compensating for the majority of patients that were not operated on. However, the worsening situation of blindness caused by cataracts due to the pandemic not be avoided in the Central-West region, where unrecovered cases continue to accumulate. CONCLUSION: The COVID-19 pandemic did not worsen the situation of cataract blindness in Brazil due to the efficacy of the measures taken by the government in resuming elective surgeries. However, the auhtors recommend that the distribution of resources for cataract surgeries should consider regional discrepancies based on epidemiological data.

Bats as ecosystem engineers in iron ore caves in the Carajás National Forest, Brazilian Amazonia.

Ecosystem engineers are organisms able to modify their environment by changing the distribution of materials and energy, with effects on biotic and abiotic ecosystem components. Several ecosystem engineers are known, but for most of them the mechanisms behind their influence are poorly known. We detail the role of bats as ecosystem engineers in iron ore caves in the Carajás National Forest, Brazilian Amazonia, an area with > 1,500 caves, some holding ~150,000 bats. We analyzed the chemical composition of guano deposits in bat caves, radiocarbon-dated those deposits, and elucidated the chemical mechanisms involved and the role the bat guano has on modifying those caves. The insect-composed guano was rich in organic matter, with high concentrations of carbon, nitrogen, phosphorus pentoxide and ferric oxide, plus potassium oxide, calcium and sulfur trioxide. Radiocarbon dating indicated guano deposits between 22,000 and 1,800 years old. The guano pH was mainly acid (from 2.1 to 5.6). Percolating waters in those bat caves were also acid (pH reaching 1.5), with the presence of phosphate, iron, calcium, nitrate and sulfate. Acid solutions due to guano decomposition and possible microbial activity produced various forms of corrosion on the caves´ floor and walls, resulting in their enlargement. Bat caves or caves with evidence of inactive bat colonies had, on average, lengths six times larger, areas five times larger, and volumes five times bigger than the regional average, plus more abundant, diversified and bigger speleothems when compared with other caves. In an example of bioengineering, the long-term presence of bats (> 22,000 years) and the guano deposits they produce, mediated by biological and chemical interactions over millennia, resulted in very unique ecological, evolutionary and geomorphological processes, whose working are just beginning to be better understood by science. However, the current expansion of mineral extraction activities coupled with the loosening of licensing and cave protection rules is a real conservation threat to the bat caves in Carajás. The destruction of those caves would represent an unacceptable loss of both speleological and biological heritage and we urge that, whenever they occur, bat caves and their colonies must be fully protected and left off-limits of mineral extraction.

Situation of ophthalmology education in Brazil: supply versus demand.

PURPOSE: The number of medical schools in Brazil has increased in recent years; however, vacancies for specialization in ophthalmology probably have not kept up with the growing demand. This study wants to estimate the increase in medical schools, the demand for ophthalmology specialization, and evaluate learning opportunities in ophthalmology. METHODS: This was a retrospective study with research from the Ministry of Education and Brazilian Council of Ophthalmology database from 2002 to 2021. These data were checked through 120 notices published by the institutions in 2021. RESULTS: The number of medical school vacancies increased by 370%, whereas the number of certified ophthalmology vacancies increased by 64%. There was an 11.4% misalignment between the Brazilian Council of Ophthalmology data in the Ministry of Education. CONCLUSION: The proportion of medical graduates has increased much more than opportunities for ophthalmology specialization. The effect on the search for unaccredited specialization positions is unknown, and policies for monitoring the specialization of ophthalmology vacancies should be established.

Proposal of a new slit-lamp shield for ophthalmic examination and assessment of its effectiveness using computational simulations.

PURPOSE: This study aimed to use computational models for simulating the movement of respiratory droplets when assessing the efficacy of standard slit-lamp shield versus a new shield designed for increased clinician comfort as well as adequate protection. METHODS: Simulations were performed using the commercial software Star-CCM+. Respiratory droplets were assumed to be 100% water in volume fraction with particle diameter distribution represented by a geometric mean of 74.4 (±1.5 standard deviation) µm over a 4-min duration. The total mass of respiratory droplets expelled from patients' mouths and droplet accumulation on the manikin were measured under the following three conditions: with no slit-lamp shield, using the standard slit-lamp shield, and using our new proposed shield. RESULTS: The total accumulated water droplet mass (kilogram) and percentage of expelled mass accumulated on the shield under the three aforementioned conditions were as follows: 5.84e-10 kg (28% of the total weight of particle emitted that settled on the manikin), 9.14e-13 kg (0.045%), and 3.19e-13 (0.015%), respectively. The standard shield could shield off 99.83% of the particles that would otherwise be deposited on the manikin, which is comparable to 99.95% for the proposed design. Conclusion: Slit-lamp shields are effective infection control tools against respiratory droplets. The proposed shield showed comparable effectiveness compared with conventional slit-lamp shields, but with potentially enhanced ergonomics for ophthalmologists during slit-lamp examinations.

Situation of ophthalmology education in Brazil: supply versus demand / A situação da educação em Oftalmologia no Brasil: oferta versus demanda

ABSTRACT Purpose: The number of medical schools in Brazil has increased in recent years; however, vacancies for specialization in ophthalmology probably have not kept up with the growing demand. This study wants to estimate the increase in medical schools, the demand for ophthalmology specialization, and evaluate learning opportunities in ophthalmology. Methods: This was a retrospective study with research from the Ministry of Education and Brazilian Council of Ophthalmology database from 2002 to 2021. These data were checked through 120 notices published by the institutions in 2021. Results: The number of medical school vacancies increased by 370%, whereas the number of certified ophthalmology vacancies increased by 64%. There was an 11.4% misalignment between the Brazilian Council of Ophthalmology data in the Ministry of Education. Conclusion: The proportion of medical graduates has increased much more than opportunities for ophthalmology specialization. The effect on the search for unaccredited specialization positions is unknown, and policies for monitoring the specialization of ophthalmology vacancies should be established.

RESUMO Objetivo: Nos últimos 20 anos, o número de escolas médicas no Brasil aumentou, mas as vagas para especialização em Oftalmologia não acompanharam a demanda crescente. Este estudo quer estimar a demanda por especialização e avaliar a oferta de oportunidades de aprendizado em Oftalmologia. Métodos: Estudo epidemiológico com pesquisa em banco de dados provenientes do Ministério da Educação e Conselho Brasileiro de Oftalmologia. Estes dados foram checados através de 120 editais publicados pelos serviços de Residência em 2021. Resultados: De 2002 a 2021, o número de vagas em faculdades de Medicina aumentou 370%, enquanto o número de vagas certificadas de especialização em Oftalmologia aumentou 64%. Houve um desalinhamento de 11.4% entre os dados do Conselho Brasileiro de Oftalmologia e do Ministério da Educação. Conclusão: A proporção de graduados em Medicina aumentou muito mais do que a oferta de oportunidades de especialização em Oftalmologia, o impacto disto na busca por vagas de especialização não acreditadas é desconhecido, políticas de monitoramento das vagas de especialização em Oftalmologia devem ser estabelecidas.

Proposal of a new slit-lamp shield for ophthalmic examination and assessment of its effectiveness using computational simulations / Avaliação da eficácia e proposta de um novo protetor de lâmpada de fenda durante exame oftálmico por meio de simulações computacionais

ABSTRACT Purpose: This study aimed to use computational models for simulating the movement of respiratory droplets when assessing the efficacy of standard slit-lamp shield versus a new shield designed for increased clinician comfort as well as adequate protection. Methods: Simulations were performed using the commercial software Star-CCM+. Respiratory droplets were assumed to be 100% water in volume fraction with particle diameter distribution represented by a geometric mean of 74.4 (±1.5 standard deviation) μm over a 4-min duration. The total mass of respiratory droplets expelled from patients' mouths and droplet accumulation on the manikin were measured under the following three conditions: with no slit-lamp shield, using the standard slit-lamp shield, and using our new proposed shield. Results: The total accumulated water droplet mass (kilogram) and percentage of expelled mass accumulated on the shield under the three aforementioned conditions were as follows: 5.84e-10 kg (28% of the total weight of particle emitted that settled on the manikin), 9.14e-13 kg (0.045%), and 3.19e-13 (0.015%), respectively. The standard shield could shield off 99.83% of the particles that would otherwise be deposited on the manikin, which is comparable to 99.95% for the proposed design. Conclusion: Slit-lamp shields are effective infection control tools against respiratory droplets. The proposed shield showed comparable effectiveness compared with conventional slit-lamp shields, but with potentially enhanced ergonomics for ophthalmologists during slit-lamp examinations.

RESUMO Introdução: Os oftalmologistas têm alto risco de contrair a doença do Coronavírus-19 devido à proximidade com os pacientes durante os exames com lâmpada de fenda. Usamos um modelo de computação para avaliar a eficácia das proteções para lâmpadas de fenda e propusemos uma nova proteção ergonomicamente projetada. Métodos: As simulações foram realizadas no software comercial Star-CCM +. Os aerossóis de gotículas foram considerados 100% de água em fração de volume com distribuição de diâmetro de partícula representada por uma média geométrica de 74,4 ± 1,5 (desvio padrão) μm ao longo de uma duração de quatro minutos. A massa total de gotículas de água acumulada no manequim e a massa expelida pela boca do paciente foram medidas em três condições diferentes: 1) Sem protetor de lâmpada de fenda, 2) com protetor padrão, 3) Com o novo protetor proposto. Resultados: A massa total acumulada das gotas de água (kg) e a porcentagem da massa expelida acumulada no escudo para cada uma das respectivas condições foram; 1) 5,84e-10 kg (28% do peso total da partícula emitida que assentou no manequim), 2) 9,14e-13 kg (0,045%), 3,19e-13 (0,015%). O escudo padrão foi capaz de proteger 99,83% das partículas que, de outra forma, teriam se depositado no manequim, o que é semelhante a 99,95% para o projeto proposto. Conclusão: Protetores com lâmpada de fenda são ferramentas eficazes de controle de infecção contra gotículas respiratórias. O protetor proposto mostrou eficácia comparável em comparação com os protetores de lâmpada de fenda convencionais, mas potencialmente oferece uma melhor ergonomia para oftalmologistas durante o exame de lâmpada de fenda.

Estimating the cost of training an ophthalmologist in Brazil / Estimativa do custo para formação de um oftalmologista no Brasil

ABSTRACT Introduction: It is estimated that 23% of the Brazilian population does not have access to an ophthalmologist, mainly because of the irregular geographical distribution of experts. It may be expensive to train ophthalmologists in Brazil. Objective: To estimate the cost of training an ophthalmologist and the labor market conditions so that the provider recovers the investment. Methods: Epidemiological study in databases from governmental sources and institutions related to the eye health system regulation. Results: The cost for training an ophthalmologist would be equal to R$ 592.272,00. After specialization, if the provider pledged all his/her income to recover the amount spent on training, it would take 5.2 years to reach the point of equilibrium. Conclusion: Young doctors from families unable to afford the cost of their education and support for at least 14 years after the beginning of the undergraduate course will hardly be able to specialize in Ophthalmology if they are unable to carry out their studies in public educational institutions. And those who can specialize are likely to choose to practice their profession in large urban centers, where most of the job opportunities are available, to at least recover the financial investment in training in the medium term.

RESUMO Introdução: Estima-se que 23% da população brasileira não tenha acesso ao oftalmologista, devido, principalmente, à falta de recursos do Sistema Público de Saúde e à distribuição geográfica irregular dos especialistas. É possível que seja caro formar oftalmologistas no Brasil. Assim, é compreensível que a maioria dos profissionais optem para ficar próximos dos grandes centros consumidores, onde estão as melhores remunerações. Objetivo: Estimar o custo para a formação de um oftalmologista e as condições do mercado de trabalho para que ele recupere o investimento. Métodos: estudo epidemiológico em bases de dados de fontes governamentais e de instituições relacionadas à regulamentação do sistema de saúde ocular. Resultados: Estimou-se que o custo para formação de um oftalmologista seja de R$ 592.272,00. Após a especialização, caso ele empenhe todo seu rendimento para reaver o valor gasto em sua formação, precisaria de 5,2 anos para atingir o ponto de equilíbrio. Conclusão: Jovens médicos oriundos de famílias incapazes de arcar com o custo de sua formação e de seu sustento, por pelo menos 14 anos após o início da graduação, dificilmente conseguirão se especializar em Oftalmologia, se não conseguirem realizar seus estudos em instituições públicas de ensino. E aqueles que conseguem se especializar, provavelmente optem por exercer a profissão em grandes centros urbanos, onde está a maior parte das oportunidades de trabalho, a fim de, a médio prazo, conseguir, pelo menos, recuperar o investimento financeiro na formação.