Parâmetros físicos (temperatura, condutividade elétrica e turbidez) na avaliação de corpos de água impactados na área urbana da cidade de Manaus, AM: Physical parameters (temperature, electrical conductivity and turbidity) in the evaluation of impacted water bodies in the urban area of the city of Manaus, AM

A Física é uma área de grande alcance na sociedade moderna, contudo, há pouca aplicação em diagnósticos ambientais usando somente variáveis físicas. Diante desse disso, o presente estudo teve por objetivo avaliar três variáveis físicas (temperatura, condutividade elétrica e turbidez) em uma bacia hidrográfica urbana localizada no centro do polo industrial de Manaus – A Bacia Hidrográfica do Educandos – BHE. Foram selecionados nove pontos na BHE e as amostras de águas foram coletadas na superfície dos corpos de águas em frascos de polietileno. As amostras foram conduzidas ao laboratório de Química Ambiental do Instituto Nacional de Pesquisas da Amazônia – INPA. A temperatura da água foi determinada no campo com um termômetro de mercúrio. Condutividade elétrica e turbidez foram analisados por métodos eletroquímicos, com instrumentos de bancada. Os resultados mostraram valores de temperatura acima de 30° C o que sugere falta de arborização nas margens dos corpos de água, valores estes mais elevados que há duas décadas. A condutividade elétrica apresentou valores acima de 400 µS cm-1 o que denota a grande quantidade de eletrólitos lançados nesses ambientes, caracterizados naturalmente como pouco condutivos, e a turbidez elevada sugere solos revolvidos nas margens. A única exceção foi o ponto P1, que ainda guarda as condições físicas naturais desta bacia hidrográfica

Bactérias consumidoras de fosfato em uma bacia hidrográfica urbana no centro da Amazônia

As preocupações mais difundidas com relação à contaminação por dejetos humanos e animais são causadas por patógenos relacionados a doenças transmitidas pela água e concentrações excessivas de nitrogênio e fósforo que provocam o fenômeno da eutrofização. Dessa forma, esse estudo teve por objetivo avaliar a interação entre a bactéria E. Coli com os teores de fosfato em uma bacia hidrográfica urbana em Manaus. Foram realizadas 14 coletas quinzenais entre os meses de setembro de 2021 e março de 2022. As amostras de água para análise de E. coli foram coletadas próximos da superfície em frascos de vidro de 100 mL, enquanto que para as análises de fosfato, as amostras foram coletadas em frascos de polietileno e acondicionadas até as análises por Colilert e espectrofotometria, respectivamente. Os resultados mostraram que as águas naturalmente ácidas de Manaus apresentaram valores de pH básicos em muitos locais (até 7,20) e que existe uma tendência linear entre fosfato e E. coli. Esse microrganismo prevaleceu em ambientes menos ácidos. Em valores de pH próximos a 7,0 a concentração de fosfato praticamente não muda, como se esse íon estivesse associado a algum tampão no meio (a partir de 0,04 mg L-1). A E. coli predominou em todos os pontos cujas concentrações de fosfato foram acima de 0,04 mg L-1, obedecendo uma tendência logarítmica típica para crescimento de microbiano. Ao contrário do que se esperava, não houve diluição em direção às fozes desta bacia hidrográfica, nem para fosfato e nem para a E. coli

Fire effect on bamboo-dominated forests in Southwestern Amazon: impacts on tree diversity and forest structure

Severe droughts increase the forest flammability, especially if fires are recurrent. Considering that fires tend to alter the forest structure and reduce biological diversity, we analyzed the fire effect on the tree plant community and forest structure over a 10-year post-fire period. The study was carried out in two tropical forest fragments located in the eastern Acre State in southwestern Brazilian Amazon. In each fragment, we established three plots of 250 × 10 m2 in an unburned forest and three in a burned forest. In these plots, we collected all tree individuals with DBH≥10 following the RAINFOR protocol, with censuses made in 2011, 2014, 2016, 2017, 2019, 2020 and 2021. The fire significantly reduced the abundance, basal area, and aboveground biomass of tree species, and altered the species composition along the post-fire temporal gradient. The absence of differences in the species richness and species diversity between unburned and burned forests is probably related to the life cycle of bamboo. The results suggest that, 10 years after the fire, the structure and phytosociology of the forest have not yet fully recovered

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

Post-intervention Status in Patients With Refractory Myasthenia Gravis Treated With Eculizumab During REGAIN and Its Open-Label Extension

OBJECTIVE: To evaluate whether eculizumab helps patients with anti-acetylcholine receptor-positive (AChR+) refractory generalized myasthenia gravis (gMG) achieve the Myasthenia Gravis Foundation of America (MGFA) post-intervention status of minimal manifestations (MM), we assessed patients' status throughout REGAIN (Safety and Efficacy of Eculizumab in AChR+ Refractory Generalized Myasthenia Gravis) and its open-label extension. METHODS: Patients who completed the REGAIN randomized controlled trial and continued into the open-label extension were included in this tertiary endpoint analysis. Patients were assessed for the MGFA post-intervention status of improved, unchanged, worse, MM, and pharmacologic remission at defined time points during REGAIN and through week 130 of the open-label study. RESULTS: A total of 117 patients completed REGAIN and continued into the open-label study (eculizumab/eculizumab: 56; placebo/eculizumab: 61). At week 26 of REGAIN, more eculizumab-treated patients than placebo-treated patients achieved a status of improved (60.7% vs 41.7%) or MM (25.0% vs 13.3%; common OR: 2.3; 95% CI: 1.1-4.5). After 130 weeks of eculizumab treatment, 88.0% of patients achieved improved status and 57.3% of patients achieved MM status. The safety profile of eculizumab was consistent with its known profile and no new safety signals were detected. CONCLUSION: Eculizumab led to rapid and sustained achievement of MM in patients with AChR+ refractory gMG. These findings support the use of eculizumab in this previously difficult-to-treat patient population. CLINICALTRIALSGOV IDENTIFIER: REGAIN, NCT01997229; REGAIN open-label extension, NCT02301624. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that, after 26 weeks of eculizumab treatment, 25.0% of adults with AChR+ refractory gMG achieved MM, compared with 13.3% who received placebo

Minimal Symptom Expression' in Patients With Acetylcholine Receptor Antibody-Positive Refractory Generalized Myasthenia Gravis Treated With Eculizumab

The efficacy and tolerability of eculizumab were assessed in REGAIN, a 26-week, phase 3, randomized, double-blind, placebo-controlled study in anti-acetylcholine receptor antibody-positive (AChR+) refractory generalized myasthenia gravis (gMG), and its open-label extension