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Delta VOC is highly diverse with more than 120 sublineages already described as of November 30, 2021. In this study, through active monitoring of circulating severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants in the state of São Paulo, southeast Brazil, we identified two emerging sublineages from the ancestral AY.43 strain which were classified as AY.43.1 and AY.43.2. These sublineages were defined by the following characteristic nonsynonymous mutations ORF1ab:A4133V and ORF3a:T14I for the AY.43.1 and ORF1ab:G1155C for the AY.43.2 and our analysis reveals that they might have a likely-Brazilian origin. Much is still unknown regarding their dissemination in the state of São Paulo and Brazil as well as their potential impact on the ongoing vaccination process. However, the results obtained in this study reinforce the importance of genomic surveillance activity for timely identification of emerging SARS-CoV-2 variants which can impact the ongoing SARS-CoV-2 vaccination and public health policies.

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The emergence of Variants of Concern (VOC) presenting an unusual number of new mutations is one of the most remarkable features of SARS-CoV-2. The Delta variant, since its appearance, replaced the VOC Gamma, which was responsible for the major COVID-19 wave in Brazil. In this study, we performed a Delta whole-genome sequencing of 183 samples as part of a major genomic surveillance study performed since the beginning of the pandemic. Here, we showed an emergence, widespread dispersion and consolidation of the Delta variant in Rio Grande do Sul State, completely replacing the Gamma variant in a four to five months period. Performing the phylogenetic and phylodynamic analysis, the majority of the sequences generated herein were classified as AY.99.2, AY.99.2-like and AY.101. AY.99.2 Delta-related lineage has been widely reported in Brazil and in the Americas as well. Altogether, our findings provided a mutational profile of the sequences and presented high substitutions per site in the root-to-tip phylogenetic tree, corroborating studies that show the high mutational rate of SARS-CoV-2 over time.

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Delta VOC is highly diverse with more than 120 sublineages already described as of November 30, 2021. In this study, through active monitoring of circulating severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants in the state of São Paulo, southeast Brazil, we identified two emerging sublineages from the ancestral AY.43 strain which were classified as AY.43.1 and AY.43.2. These sublineages were defined by the following characteristic nonsynonymous mutations ORF1ab:A4133V and ORF3a:T14I for the AY.43.1 and ORF1ab:G1155C for the AY.43.2 and our analysis reveals that they might have a likely-Brazilian origin. Much is still unknown regarding their dissemination in the state of São Paulo and Brazil as well as their potential impact on the ongoing vaccination process. However, the results obtained in this study reinforce the importance of genomic surveillance activity for timely identification of emerging SARS-CoV-2 variants which can impact the ongoing SARS-CoV-2 vaccination and public health policies.

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The densification of multiple wireless communication systems that coexist nowadays, as well as the 5G new generation cellular systems advent towards the millimeter wave (mmWave) frequency range, give rise to complex context-aware scenarios with high-node density heterogeneous networks. In this work, a radiofrequency electromagnetic field (RF-EMF) exposure assessment from an empirical and modeling approach for a large, complex indoor setting with high node density and traffic is presented. For that purpose, an intensive and comprehensive in-depth RF-EMF E-field characterization study is provided in a public library study case, considering dense personal mobile communications (5G FR2 @28 GHz) and wireless 802.11ay (@60 GHz) data access services on the mmWave frequency range. By means of an enhanced in-house deterministic 3D ray launching (3D-RL) simulation tool for RF-EMF exposure assessment, different complex heterogenous scenarios of high complexity are assessed in realistic operation conditions, considering different user distributions and densities. The use of directive antennas and MIMO beamforming techniques, as well as all the corresponding features in terms of radio wave propagation, such as the body shielding effect, dispersive material properties of obstacles, the impact of the distribution of scatterers and the associated electromagnetic propagation phenomena, are considered for simulation. Discussion regarding the contribution and impact of the coexistence of multiple heterogeneous networks and services is presented, verifying compliance with the current established international regulation limits with exposure levels far below the aforementioned limits. Finally, the proposed simulation technique is validated with a complete empirical campaign of measurements, showing good agreement. In consequence, the obtained datasets and simulation estimations, along with the proposed RF-EMF simulation tool, could be a reference approach for the design, deployment and exposure assessment of the current and future wireless communication technologies on the mmWave spectrum, where massive high-node density heterogeneous networks are expected.

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The purpose of this study was to evaluate iffreezing-thawing and cooling processes affect thestructural properties and biological activity ofcommercial equine chorionic gonadotropin (eCG). First,the structure profile of diluted eCG underwent none,one or three cycles of freezing-thawing was analysed byreverse phase high-performance liquid chromatography(RP-HPLC). In a second experiment, groups ofprepuberal rats were treated with sterile water forinjection USP or eCG that underwent none, one or threecycles of freezing-thawing to assess the increase ofovarian weigh. Finally, groups of prepubertal gilts weretreated with diluted eCG immediately afterreconstitution (T1), after refrigeration for six months(T2) and after freezing and subsequently thawing for one(T3) or three (T4) cycles. The control group (T5) receivedsterile water for injection USP without eCG. Ovulationwas induced with human chorionic gonadotropin (hCG),administered 72 h after the eCG. Gilts were slaughteredfive days after the hCG injection and ovaries wererecovered and analysed for the presence of corporalutea. Data were analysed by ANOVA and Fisher’sexact tests. In the analyses by RP-HPLC, the retentiontimes of cold stressed eCG were similar to unstressedcontrol. The mean ovarian weight of rats treated with coldstressed and unstressed eCG was statistically higher thanwater control (P < 0.05). Lastly, significantly more giltsovulated in groups T1, T2, T3 and T4 than in thecontrol T5 (P < 0.05). It was concluded that freezingthawing,as well as cooling over a period of up to sixmonths, did not significantly change the structuralproperties or biological activity of eCG.

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The purpose of this study was to evaluate iffreezing-thawing and cooling processes affect thestructural properties and biological activity ofcommercial equine chorionic gonadotropin (eCG). First,the structure profile of diluted eCG underwent none,one or three cycles of freezing-thawing was analysed byreverse phase high-performance liquid chromatography(RP-HPLC). In a second experiment, groups ofprepuberal rats were treated with sterile water forinjection USP or eCG that underwent none, one or threecycles of freezing-thawing to assess the increase ofovarian weigh. Finally, groups of prepubertal gilts weretreated with diluted eCG immediately afterreconstitution (T1), after refrigeration for six months(T2) and after freezing and subsequently thawing for one(T3) or three (T4) cycles. The control group (T5) receivedsterile water for injection USP without eCG. Ovulationwas induced with human chorionic gonadotropin (hCG),administered 72 h after the eCG. Gilts were slaughteredfive days after the hCG injection and ovaries wererecovered and analysed for the presence of corporalutea. Data were analysed by ANOVA and Fishersexact tests. In the analyses by RP-HPLC, the retentiontimes of cold stressed eCG were similar to unstressedcontrol. The mean ovarian weight of rats treated with coldstressed and unstressed eCG was statistically higher thanwater control (P < 0.05). Lastly, significantly more giltsovulated in groups T1, T2, T3 and T4 than in thecontrol T5 (P < 0.05). It was concluded that freezingthawing,as well as cooling over a period of up to sixmonths, did not significantly change the structuralproperties or biological activity of eCG.(AU)

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AIM: By using the finite element method (FEM), this study aimed to evaluate the effect of different corticotomy formats on the distribution and magnitude of stress on the periodontal ligament (PDL) during retraction of the maxillary canine. MATERIALS AND METHODS: A geometric model of the left hemi-jaw was created from computed tomography scan images of a dry human skull and loads were administered during distalization movement of the canine. Three trials were performed: (1) without corticotomy, (2) box-shaped corticotomy and perforations in the cortical bone of the canine (CVC) and (3) CVC and circular-shaped corticotomy in the cortical bone of the edentulous space of the first premolar. RESULTS: There was no difference in stress distribution among the different corticotomy formats. CONCLUSION: Different corticotomy formats used to accelerate orthodontic tooth movement did not affect stress distribution in the PDL during canine retraction. CLINICAL SIGNIFICANCE: From a mechanical perspective, the present study showed that the stress distribution on the PDL during canine retraction was similar in all the corticotomy formats. When using the Andrews T2 bracket, the PDL presented the highest levels of stress in the middle third of the PDL, suggesting that the force was near the center of resistance. Also, as bone weakening by corticotomies did not influence stress distribution, the surgical procedure could be simplified to a less aggressive one, focusing more on inflammatory cellular stimulation than on bone resistance. A simpler surgical act could also be performed by most orthodontists in their practices, enhancing postoperative response and reducing patient costs.

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Bioluminescent bacteria are widespread in natural environments. Over the years, many researchers have been studying the physiology, biochemistry and genetic control of bacterial bioluminescence. These discoveries have revolutionized the area of Environmental Microbiology through the use of luminescent genes as biosensors for environmental studies. This paper will review the chronology of scientific discoveries on bacterial bioluminescence and the current applications of bioluminescence in environmental studies, with special emphasis on the Microtox toxicity bioassay. Also, the general ecological significance of bioluminescence will be addressed.

Bactérias que emitem bioluminescência são amplamente distribuídas em ambientes naturais. Ao longo dos anos vários pesquisadores vêm estudando a fisiologia, bioquímica e controle genético da bioluminescência. Essas descobertas têm revolucionado a Área de Microbiologia Ambiental através da utilização dos genes lux como biosensores em estudos ambientais. Esta revisão examinará a cronologia de descobertas científicas da bioluminescência bacteriana e as aplicações atuais em estudos ambientais, salientando a utilização do teste de toxicidade Microtox. A significância ecológica da bioluminescência será também examinada.