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The Lassa virus is endemic in parts of West Africa, and it causes hemorrhagic fever with high mortality. The development of a recombinant protein vaccine has been hampered by the instability of soluble Lassa virus glycoprotein complex (GPC) trimers, which disassemble into monomeric subunits after expression. Here, we use two-component protein nanoparticles consisting of trimeric and pentameric subunits to stabilize GPC in a trimeric conformation. These GPC nanoparticles present twenty prefusion GPC trimers on the surface of an icosahedral particle. Cryo-EM studies of GPC nanoparticles demonstrated a well-ordered structure and yielded a high-resolution structure of an unliganded GPC. These nanoparticles induced potent humoral immune responses in rabbits and protective immunity against the lethal Lassa virus challenge in guinea pigs. Additionally, we isolated a neutralizing antibody that mapped to the putative receptor-binding site, revealing a previously undefined site of vulnerability. Collectively, these findings offer potential approaches to vaccine and therapeutic design for the Lassa virus.

RESUMO Objetivo: Avaliar as modificações nas características das paradas cardíacas no hospital após a implantação de um Time de Resposta Rápida. Métodos: Este foi um estudo observacional prospectivo de paradas cardíacas ocorridas no hospital entre janeiro de 2013 e dezembro de 2017. O critério de exclusão foi parada cardíaca na unidade de terapia intensiva, na emergência ou na sala cirúrgica. O Time de Resposta Rápida foi introduzido no hospital do estudo em julho de 2014. Os pacientes foram classificados em dois grupos: Pré-Time de Resposta Rápida (parada cardíaca no hospital antes da implantação do Time de Resposta Rápida) e Pós- Time de Resposta Rápida (parada cardíaca no hospital após a implantação do Time de Resposta Rápida). Os pacientes foram seguidos até a alta hospitalar ou óbito. Resultados: Ocorreram 308 paradas cardíacas (64,6 ± 15,2 anos; 60,3% homens; 13,9% com ritmo inicial chocável). Houve diminuição de 4,2 para 2,5 no índice de parada cardíaca no hospital por 1.000 admissões após o início da atuação do Time de Resposta Rápida, além de cerca de 124 chamados por 1.000 admissões. A parada antes da implantação do Time de Resposta Rápida se associou com hipóxia (29,4 versus 14,3%; p = 0,006) e alteração da frequência respiratória (14,7 versus 4,2%; p = 0,004) em comparação aos dados referentes à parada cardíaca após a implantação do Time de Resposta Rápida. Parada cardíaca por hipóxia foi mais comum antes da implantação do Time de Resposta Rápida (61,2 versus 38,1%; p < 0,001). Na análise multivariada, o retorno à circulação espontânea se associou com ritmo chocável (RC 2,97; IC95% 1,04 - 8,43) e parada cardíaca testemunhada (RC 2,52; IC95% 1,39 - 4,59) mas não com a implantação do Time de Resposta Rápida (RC 1,40; IC95% 0,70 - 2,81) ou sinais premonitórios (RC 0,71; IC95% 0,39 - 1,28). Na análise multivariada, a mortalidade hospitalar se associou com ritmo não chocável (RC 5,34; IC95% 2,28 - 12,53) e idade (RC 1,03; IC95% 1,01 - 1,05), porém não com a implantação do Time de Resposta Rápida (RC 0,89; IC95% 0,40 - 2,02). Conclusão: Apesar de a implantação de um Time de Resposta Rápida se associar com redução na incidência de parada cardíaca no hospital, ela não se associou com a redução da mortalidade das vítimas de parada cardíaca no hospital. Observou-se significante diminuição nas paradas cardíacas devidas a causas respiratórias após a implantação do Time de Resposta Rápida. ABSTRACT Objective: To evaluate changes in the characteristics of in-hospital cardiac arrest after the implementation of a Rapid Response Team. Methods: This was a prospective observational study of in-hospital cardiac arrest that occurred from January 2013 to December 2017. The exclusion criterion was in-hospital cardiac arrest in the intensive care unit, emergency room or operating room. The Rapid Response Team was implemented in July 2014 in the study hospital. Patients were classified into two groups: a Pre-Rapid Response Team (in-hospital cardiac arrest before Rapid Response Team implementation) and a Post-Rapid Response Team (in-hospital cardiac arrest after Rapid Response Team implementation). Patients were followed until hospital discharge or death. Results: We had a total of 308 cardiac arrests (64.6 ± 15.2 years, 60.3% men, 13.9% with initial shockable rhythm). There was a decrease from 4.2 to 2.5 in-hospital cardiac arrest/1000 admissions after implementation of the Rapid Response Team, and we had approximately 124 calls/1000 admissions. Pre-Rapid Response Team cardiac arrest was associated with more hypoxia (29.4 versus 14.3%; p = 0.006) and an altered respiratory rate (14.7 versus 4.2%; p = 0.004) compared with post-Rapid Response Team cardiac arrest. Cardiac arrest due to hypoxia was more common before Rapid Response Team implementation (61.2 versus 38.1%, p < 0.001). In multivariate analysis, return of spontaneous circulation was associated with shockable rhythm (OR 2.97; IC95% 1.04 - 8.43) and witnessed cardiac arrest (OR 2.52; IC95% 1.39 - 4.59) but not with Rapid Response Team implementation (OR 1.40; IC95% 0.70 - 2.81) or premonitory signs (OR 0.71; IC95% 0.39 - 1.28). In multivariate analysis, in-hospital mortality was associated with non-shockable rhythm (OR 5.34; IC95% 2.28 - 12.53) and age (OR 1.03; IC95% 1.01 - 1.05) but not with Rapid Response Team implementation (OR 0.89; IC95% 0.40 - 2.02). Conclusion: Even though Rapid Response Team implementation is associated with a reduction in in-hospital cardiac arrest, it was not associated with the mortality of in-hospital cardiac arrest victims. A significant decrease in cardiac arrests due to respiratory causes was noted after Rapid Response Team implementation.

O objetivo deste trabalho foi avaliar o desenvolvimento de bananeiras ‘Grand Naine’ e ‘BRS Tropical’ sob diferentes tipos de adubos orgânicos no primeiro ciclo de produção. O delineamento experimental foi em blocos casualizados com quatro repetições de quatro plantas cada. Os tratamentos constituíram-se por: esterco de bovinos, esterco de aves, efluente de suínos, composto de esterco de bovinos, composto de esterco de aves e composto de efluente de suínos. Por ocasião da emissão da inflorescência, foram realizadas as seguintes avaliações: determinação da circunferência do pseudocaule, altura do pseudocaule até a inserção da inflorescência, número de folhas vivas por planta e a duração do ciclo da cultura. Na pós-colheita, avaliou-se a massa do cacho e da segunda penca, número de pencas e frutos por cacho, número de frutos na segunda penca, comprimento e diâmetro dos frutos, pH, sólidos solúveis e acidez titulável. Os adubos orgânicos aplicados na bananeira ‘Grand Naine’ contribuiram para o aporte no diâmetro do pseudocaule e nas características dos cachos e dos frutos, e reduziu o ciclo reprodutivo da bananeira ‘BRS Tropical’, comprovando-se que é possível nutrir e produzir frutos dessas cultivares de bananeiras com padrão comercial e ainda aproveitar os resíduos gerados na propriedade rural já no primeiro ciclo de produção.

Lassa virus is endemic in large parts of West Africa and causes a hemorrhagic fever. Recent years have seen several serious outbreaks of Lassa fever with high mortality rates. A vaccine to curtail infection is urgently needed. The development of a recombinant protein vaccine has been hampered by the instability of soluble Lassa virus glycoprotein complex (GPC) trimers, which disassemble into monomeric subunits after expression. Here we use two-component protein nanoparticles to stabilize GPC in a trimeric conformation and present twenty prefusion GPC trimers on the surface of an icosahedral nanoparticle. Cryo-EM studies of assembled GPC nanoparticles demonstrated a well-ordered structure and yielded a high-resolution structure of an unliganded GPC. These nanoparticles induced potent humoral immune responses in rabbits and protective immunity against a lethal Lassa virus challenge in guinea pigs. We isolated a neutralizing antibody which was mapped to the putative receptor-binding site, revealing a novel site of vulnerability on GPC.

A third mRNA-based “booster” vaccination is the favored strategy to maintain protection against SARS-CoV-2 infection. Yet, significant waning of specific immunity within six months after 2nd vaccination, along with higher incidence of breakthrough infections associated with the time elapsed since 2nd vaccination raises concerns regarding the durability of immunity also after 3rd vaccination. We assessed virus-specific serum antibody and T cell response in the blood after vaccination with the mRNA vaccine BNT162b2 in more than 50 individuals older than 80 years. All old adults demonstrated a strong humoral response to 3rd vaccination which was at average higher and waned slower than the response to 2nd vaccination, indicative of enhanced humoral immunity. In contrast, their respective T cell response quantitatively limited to the level obtained after 2nd vaccination, with similar waning over time and no evidence for enhanced IFNg production. Because BNT162b2-mediated protection from the Omicron variant relies more on T cells than antibodies, our findings raise concern on the durability of protection from the Omicron variant by BNT162b2 in the senior population.

Space is a key element of human life that holds significance across the life course. Spaces, territories and symbolic arrangements are elements of social reality. This chapter examines the role of space in the context of transitions. Our conceptualization of space does not reduce it to qualities of an external environment but views it as a relational arrangement of people and features that are crucial for understanding transitions across the life course instead. Drawing from two empirical studies anchored in dispositive analysis and environmental psychology, we examine (a) transitions to children’s independent mobility, and (b) transitions into multigenerational cohousing. We ask: How can spatial sensitivity shape, challenge and enrich research on transitions in childhood and later life?

Based on concepts from environmental gerontology and life-span psychology, this study aims at comparing perceived housing and person-environment (p-e) fit across three age groups. Young (20–30 year...

Os teores de proteína e óleo são governados geneticamente, contudo fortemente influenciados pelo ambiente. Assim objetivou-se avaliar a distribuição espacial dos teores de proteína e óleo de sementes de soja cultivada em um campo de produção. Foram realizadas amostragens de sementes, em pontos georreferenciados, para obtenção do teor de proteína e óleo pela técnica da Refletância do Infravermelho Próximo (NIR). Os teores médios de proteína e óleo foram de 35,92% e 20,65%, respectivamente. As variáveis estudadas apresentaram dependência espacial moderada e ajuste ao semivariograma esférico. Os valores do alcance de dependência espacial variaram de 249,99 m, para o teor de óleo, a 414,92 m para o teor de proteína. Foram elaborados mapas de distribuição espacial das variáveis. Existe dependência espacial dos teores de proteína e óleo avaliados nas sementes de soja. A avaliação da qualidade bioquímica das sementes pode indicar parâmetros para o setor de melhoramento genético na escolha do material a ser utilizado nas próximas safras na área de produção.

Here we compared SARS-CoV-2-specific antibody and T-cell responses between older adults (80 years old, n = 51) and a younger control group (20-53 years old, n = 46) after receiving two doses of BNT162b2. We found that responses in older adults were generally lower, and we identified 10% low-/non-responders. After receiving a third vaccination with BNT162b2, 4 out of 5 low-/non-responders showed antibody and T-cell responses similar to those of responders after two vaccinations.

The current Severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) pandemic is a public health emergency of international concern. Sensitive and precise diagnostic tools are urgently needed. In this study, we developed a SARS-CoV-2 spike (S1) protein enzyme-linked immunosorbent assay (ELISA) to detect SARS-CoV-2-specific antibodies. The SARS-CoV-2 S1 ELISA was found to be specific [97.8% (95% CI, 96.7% - 98.5%)], reproducible and precise (intra-assay coefficient of variability (CV) 5.3%, inter-assay CV 7.9%). A standard curve and the interpolation of arbitrary ELISA units per milliliter served to reduce the variability between different tests and operators. Cross-reactivity to other human coronaviruses was addressed by using sera positive for MERS-CoV- and hCoV HKU1-specific antibodies. Monitoring antibody development in various samples of twenty-three and single samples of twenty-nine coronavirus disease 2019 (COVID−19) patients revealed seroconversion and neutralizing antibodies against authentic SARS-CoV-2 in all cases. The comparison of the SARS-CoV-2 (S1) ELISA with a commercially available assay showed a better sensitivity for the in-house ELISA. The results demonstrate a high reproducibility, specificity and sensitivity of the newly developed ELISA, which is suitable for the detection of SARS-CoV-2 S1 protein-specific antibody responses., Highlights • A highly sensitive and specific SARS-CoV-2 S1 ELISA was developed. • A standard curve is included to reduce variability between assays and operators. • Excellent intra-assay coefficient of variability (CV) 5.3%, inter-assay CV 7.9%. • Good correlation to the virus neutralization test VNT100.

The emergence of SARS-CoV-2 highlights the global need for platform technologies to enable the rapid development of diagnostics, vaccines, treatments, and personal protective equipment (PPE). However, many current technologies require the detailed mechanistic knowledge of specific material-virion interactions before they can be employed, for example, to aid in the purification of vaccine components or in the design of a more effective PPE. Here, we show that an adaption of a polymer microarray method for screening bacterial-surface interactions allows for the screening of polymers for desirable material-virion interactions. Nonpathogenic virus-like particles including fluorophores are exposed to the arrays in an aqueous buffer as a simple model of virions carried to the surface in saliva/sputum. Competitive binding of Lassa and Rubella virus-like particles is measured to probe the relative binding properties of a selection of copolymers. This provides the first step in the development of a method for the discovery of novel materials with promise for viral binding, with the next being development of this method to assess absolute viral adsorption and assessment of the attenuation of the activity of live virus, which we propose would be part of a material scale up step carried out in high containment facilities, alongside the use of more complex media to represent biological fluids.

The emergence of SARS-CoV-2 highlights the global need for platform technologies to enable rapid development of diagnostics, vaccines, treatments, and personal protective equipment (PPE). However, many current technologies require the detailed mechanistic knowledge of specific material-virion interactions before they can be employed, for example to aid in the purification of vaccine components, or in design of more effective PPE. Here we show that an adaption of polymer micro array method for screening bacterial-surface interactions allows for screening of polymers for desirable material-viron interactions. Non-pathogenic virus like particlesincluding fluorophores are exposed to the arrays in aqueous buffer as a simple model of virons carried to the surface in saliva/sputum. Competitive binding of Lassa and Rubella particles is measured to probe the relative binding properties of a selection of copolymers. This provides the first step in the development of a method for discovery of novel materials with promise for viral binding, with the next being development of this method to assess absolute viral adsorption and assessment of the attenuation of the activity of live virus which we propose would be part of a material scale up step carried out in biological laboratory safety level 4 facilities and the use of more complex media to represent biological fluids.

DNA analysis can yield information usable to identify individuals or to associate suspects, victims, and crime scene to one another but does not support a contextualization of trace material. Knowing the composition of biological material from a crime scene, e.g. whether a stain contains saliva or semen, is complementary to DNA-based identification and can be essential in reconstructing the course of events in criminal investigations. Research in the forensic applications of RNA analysis has surged considerably during the last two decades and provided recent advancements for forensic casework. Therefore, as a proof of concept, different commercially available DNA extraction kits were compared to assess their potential to simultaneously co-isolate messengerRNA and microRNA in DNA eluates of forensically relevant materials. The results showed that only one extraction kit elutes enough RNA molecules to perform messengerRNA body fluid identification whereas for microRNA-specific expression two of the tested kits yielded sufficient RNA concentrations.

Free flaps in combination with arterial reconstruction by means of arteriovenous loops or bypass have, meanwhile, been established as a therapeutic option in defect reconstruction for areas without recipient vessels. Our aim was to analyse the long‐term performance, flap autonomy, and the flap perfusion. Patients receiving this combined reconstruction at a single‐centre institution were included. During follow‐up examination, the patency of arterial reconstruction was investigated by duplex ultrasound. Flap micro‐circulation was assessed by laser Doppler flowmetry and white light tissue spectrometry (O2C) as well as by indocyanine green fluorescence angiography. Twenty‐three patients could be clinically followed up. Duplex ultrasound showed, in four cases, arterial pedicle occlusion in spite of vital flap. Comparison of the O2C perfusion parameters between flaps with occluded pedicles and those with intact inflow showed no significant difference (parameters sO2: P = .82; Flow: P = .31). Similar results were obtained by fluorescence angiography; no significant difference could be detected between both groups (parameters Ingress P = .13; Ingressrate P = .54). Combined vascular reconstruction with free tissue transfer is associated with a good long‐term outcome and wound closure. Even after flap transplantation to areas with critical tissue perfusion, the flap can develop autonomy and thus survive after pedicle occlusion.

Lassa mammarenavirus (LASV) is a rodent-borne arenavirus endemic to several West African countries. It is the causative agent of human Lassa fever, an acute viral hemorrhagic fever disease. To date, no therapeutics or vaccines against LASV have obtained regulatory approval. Polyclonal neutralizing antibodies derived from hyperimmunized animals may offer a useful strategy for prophylactic and therapeutic intervention to combat human LASV infections. The LASV envelope surface glycoprotein complex (GP) is the major target for neutralizing antibodies, and it is the main viral antigen used for the design of an LASV vaccine. Here, we assessed the immunogenic potential of mammalian cell-derived virus-like particles (VLPs) expressing GP from the prototypic LASV strain Josiah in a native-like conformation as the sole viral antigen. We demonstrate that an adjuvanted prime-boost immunization regimen with GP-derived VLPs elicited neutralizing antibody responses in rabbits, suggesting that effective antigenic epitopes of GP were displayed. Notably, these antibodies exhibited broad reactivity across five genetic lineages of LASV. VLP-based immunization strategies may represent a powerful approach for generating polyclonal sera containing cross-reactive neutralizing antibodies against LASV.

Aggressive fluid resuscitation has been extensively discussed after the establishment of fluid creep phenomenon as a morbidity and mortality factor in burn children. Sepsis is currently the leading cause of death in survivors of burn shock.To evaluate the association between fluid creep and infection in burn children exposed to two different fluid resuscitation strategies with the use of albumin.A cohort of 46 burn children with 15-45% of body surface area (BSA) admitted up to 12 h after the incident were evaluated. Patients from early albumin group (n = 23) received 5% albumin between 8 and 12 h from injury and patients from delayed albumin group (n = 23) received 5% albumin after 24 h. Outcomes analysed were development of fluid creep, length of stay in the hospital, number of surgery procedures and infection until hospital discharge.Compared to the delayed group, patients that received early albumin had a shorter length of stay in the hospital (p = 0.007), less fluid creep (4.3% × 56.5%) (p0.001), less skin graft procedure (47.8% × 78.3%) (p = 0.032) and less debridement (73.9% × 100%) (p = 0.022). Both length of stay in the hospital and fluid creep arising were associated with infection (p0.05).Fluid creep, surgery procedures and length of stay in hospital parameters showed better results in burn children treated with early albumin. Fluid creep and length of stay in the hospital were associated with infection, providing a negative prognosis.

Introdução: A ressuscitação fluídica agressiva, com volume superior ao preconizado por Baxter, com objetivo de evitar a hipoperfusão de órgãos e restabelecer a volemia rapidamente, se tornou uma tendência nos últimos anos. Esta prática vem sendo discutida mais recentemente após a caracterização do fenômeno fluid creep e pode ser causa de aumento da morbidade e mortalidade em crianças queimadas. A hiperhidratação impacta negativamente a evolução desses pacientes e já se estabeleceram associações do fenômeno fluid creep com diversas complicações, como, por exemplo, a síndrome compartimental abdominal. Pacientes queimados estão sob alto risco para infecção e sepse devido à perda da integridade da pele e à exposição prolongada ao ambiente nosocomial. A principal causa de óbito, se o paciente sobreviver à fase inicial do choque do queimado é a disfunção de múltiplos órgãos e sistemas secundária a sepse. Objetivos: Avaliar a associação entre o fluid creep e episódios infecciosos em crianças queimadas submetidas a duas estratégias diferentes de reanimação hídrica envolvendo albumina. Realizar análises de curvas de probabilidade livre de infecção, além de comparar o tempo de internação e número de procedimentos cirúrgicos realizados nestes grupos de pacientes. Metodologia: Estudo de coorte histórica envolvendo 46 crianças queimadas admitidas no Centro de Tratamento de Queimados do Hospital Universitário de Londrina entre junho de 2012 e janeiro de 2014 e que incluiu casos oriundos de um ensaio clínico randomizado controlado realizado no mesmo período. Foram incluídas crianças entre 1 e 12 anos, com queimaduras entre 15% e 45% de Superfície Corporal Queimada (SCQ) e profundidade de 2º e 3º graus, admitidas até a 12ª hora após o acidente. Todos os pacientes receberam reanimação fluídica com Ringer Lactato (RL), nas primeiras 24 horas, segundo a Fórmula de Parkland modificada (3ml/kg/%SCQ) ajustada de acordo com o débito urinário (DU). Os pacientes do grupo A = Exposto (n=23) receberam albumina 5% entre 8 e 12 horas do momento do acidente, e os do Grupo B= Não Exposto (n=23) receberam albumina 5% partir da 24a hora do acidente. Os grupos foram comparados quanto ao surgimento do fenômeno fluid creep, tempo de internação, número de procedimentos cirúrgicos realizados e infecção até a alta hospitalar. Resultados: Os pacientes do grupo A tiveram menos dias de internação comparadamente ao grupo B (p=0,007). O surgimento do fenômeno fluid creep foi maior em crianças no grupo B (p < 0,001). O tempo de internação maior de 14 dias assim como a presença de fluid creep foi associado com a presença de infecção, respectivamente p=0,002 e p=0,020. O tempo de internação bem como a presença de fluid creep apresentaram diferenças nas curvas de probabilidade livre de infecção (p < 0,05). Todas as crianças do grupo B receberam debridamento comparado com 73,9% daquelas incluídas no grupo A (p=0,022), assim como os enxertos foram mais frequentes no grupo B (p=0,032). Conclusões: Crianças queimadas que receberam albumina entre 8 e 12 horas após o acidente apresentaram significativamente menos fluid creep, menor tempo de internação e menor número de procedimentos cirúrgicos (debridamentos e enxertos) comparativamente ao grupo que recebeu albumina após 24 horas. A presença do fluid creep e o tempo de internação superior a 14 dias apresentaram diferenças nas curvas de probabilidade livre de infecção, demonstrando pior prognóstico infeccioso Introduction: Aggressive fluid resuscitation, defined as the administration of a superior volume to the parameters recommended by Baxter, intend to rapidly set the euvolemia and avoid organ hypoperfusion in burn individuals. The practice became a trend during the last years and has been extensively discussed after the establishment of the fluid creep phenomenon and has been considered as a possible mortality and morbidity factor in burn children. A strong association of fluid creep development has already been established with many conditions, as abdominal compartment syndrome. Burn patients are at high risk of infection and subsequent progression to sepsis due to the loss of skin integrity and long-term exposure to hospital environment. If those patients survive to the burn shock, their main cause of death is the multiple organ failure secondary to sepsis, what highlights the importance of comprehensive knowledge of infectious complications in burn children. Objectives: Assess the association between fluid creep and infection episodes in burn children that were exposed to two different fluid resuscitation strategies with the use of albumin. Analyze the patients infection-free probability curves, length of stay and number of surgery procedures needed. Methods: We developed a historic cohort of 46 burn children admitted at the Burn Treatment Center, State University of Londrina. The same patients were simultaneously enrolled in a parallel clinical trial. In this study, were included patients from 1 to 12 years old, with 15% to 45% of the body surface area (BSA) compromised, second or third-degree burns, admitted up to 12 hours after the accident. Both groups were compared according to the exposure. All the patients received fluid resuscitation with Ringer Lactate (RL) in the first 24 hours, respecting the modified Parkland formula (3 ml/kg/% TBSA) adjusted according to the urine output (UO). Patients from group A were exposed to 5% albumin between 8 and 12 hours from the accident moment and the patients from group B received 5% albumin after 24 hours from the accident. The outcomes observed were development of fluid creep phenomenon, length of stay, number of surgery procedures needed and infection until the hospital discharge. Results: Compared to the group B, the group A had a shorter median length of stay (p=0,007). Fluid creep development had higher rates on group B compared to group A (p < 0,001). The length of stay for more than 14 days, as the fluid creep arising, was associated with infection (respectively, p=0,002 and p=0,02). Both the length of stay and the fluid creep presence showed difference at the infection-free probability curves (p < 0,05). All the patients from group B were submitted to debridement compared to 73,9 from group A (p=0,022). The need of skin graft procedure was also more frequent in patients from group A (p=0,032). Conclusion: Burn children that received albumin between 8 and 12 hours from the accident moment presented significant less fluid creep, shorter length of stay, and smaller number of surgery procedures (as debridement and skin graft) compared to the group that received albumin after 24 hours from the accident. Fluid creep development and length of stay superior to 14 days presented differences at the infection-free probability curves, providing a negative infectious prognosis

The development and validation of a simple, reliable and fast method for the determination of cadmium and lead in fish and shrimp by GF AAS, following sample freeze-drying and tetramethylammonium hydroxide (TMAH) solubilization, is presented. The method development was achieved by sequentially applying factorial designs until optimization within the bilinear approximation of the method was accomplished. As such, seven experimental parameters were initially studied, which were considered important for the determination of cadmium and lead in seafood samples using TMAH solubilization. The validation of the method was completed in order to comply with international food regulations and method accreditation under ISO 17025. In this sense, the following parameters were evaluated: linearity, limits of detection and quantification, precision, recovery (trueness), specificity and robustness. Linearity of response was satisfactory for the concentration ranges of both analytes. The residuals for both elements were homoscedastic and independent, with normal distributions. Limits of quantification (LOQ), based on signal standard deviation for low-in-cadmium and lead samples, were 6.25 μg kg−1 and 31.25 μg kg−1, respectively. These figures are in accordance with performance criteria required by the Commission Regulation (EU) no 836/2011. The repeatability of the method, calculated from the analysis of seven sample replicates at two concentration levels of cadmium and lead, by the same analyst, was usually better than 10%. Recovery was estimated from the repeatability evaluation, lying in the range of 84% to 99% for cadmium, and 94% to 107% for lead. Furthermore, a wide evaluation of the method robustness was performed during the method optimization. Thus, the results showed the suitability of the developed method for the determination of Cd and Pb in fish and shrimp by GF AAS, following TMAH solubilization for food control purposes. Additionally, the use of sequential factorial designs in order to achieve bilinear optimization of the method was proven to be a very valuable tool, by sharply reducing optimization time and the number of experiments.

RESUMO: A presente pesquisa objetivou avaliar a qualidade fisiológica de sementes de pimenta (Capsicum chinense Jacq.) var. Bode Vermelha obtidas de frutos em diferentes estádios de maturação. Os frutos de C. chinense foram separados em cinco estádios de maturação, baseando-se na coloração do pericarpo (frutos verdes - estádio 1, frutos alaranjados - estádio 2, frutos vermelhos-claros - estádio 3, frutos vermelhos - estádio 4 e frutos vermelho-carmim - estádio 5). Para a avaliação da maturação e da qualidade fisiológica das sementes foram determinadas as características biométricas dos frutos e sementes, massa de mil sementes, teor de água das sementes, condutividade elétrica, teste padrão de germinação, tempo médio de germinação, porcentagem de plântulas normais, velocidade de formação de plântulas, além dos testes de envelhecimento acelerado, e comprimento de plântulas. Os caracteres comprimento, diâmetro, massa e número de sementes dos frutos e comprimento, largura, espessura e massa das sementes foram analisados por meio de parâmetros estimados utilizando-se estatística descritiva. Para as demais variáveis foi utilizado delineamento experimental inteiramente casualizado. Os resultados foram submetidos à análise de variância e a comparação de médias pelo teste Scott-Knott, ao nível de 5% de probabilidade. O estádio de maturação influencia na qualidade fisiológica das sementes de Capsicum chinense Jacq. var. Bode Vermelho, sendo as sementes oriundas de frutos de coloração vermelho (estádio 4) a vermelho-carmim (estádio 5) as que apresentaram os melhores desempenhos e, portanto, estão fisiologicamente maduras, sendo os mais indicados para obtenção das sementes. ABSTRACT: This research aimed to evaluate the physiological quality of pepper (Capsicum chinense Jacq.) var. Bode Vermelha seeds, obtained from fruits at different ripening stages. The fruits of C. Chinese were separated according to the ripening stages, based on pericarp color (green fruits - stage 1, orange fruits - stage 2, light red fruits - stage 3, red fruits - stage 4, and carmine-red fruits - stage 5). To evaluate the ripeness and the physiological quality of the seeds were determined the biometric characteristics of the fruits and seeds, mass of thousand seeds, seeds water content, electrical conductivity, standard germinations test, speed of germination index, percentage of normal seedlings, speed of seedlings formation, accelerated aging, and seedling length. The characters length, diameter, weight, and number of seeds of the fruits and length, width, thickness, and mass of the seeds were analyzed by the estimated parameters using descriptive statistics. For the other variables was used the completely randomized design. The results were submitted to variance analysis and comparison of means by the Scott-Knott test at 5% probability. The ripeness stage affects the physiological quality of C. chinense Jacq. var. Bode Red seeds, being the seeds from red (stage 4) to carmine-red (stage 5) fruits those with the best performance thus, they are physiologically ripe, being the most indicated to seeds obtaining.