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Natural products, specifically plant extracts with biological activity and the ability to act as botanical biopesticides are often mistakenly considered nontoxic. Scientific evidence indicates the contrary, and for this reason, the objective of this work was to evaluate the toxicity of extracts obtained from Petiveria alliacea L. (Caryophyllales, Phytolaccaceae) using Daphnia magna Straus (Cladocera, Daphniidae) as a bioindicator to identify the plant extracts and the respective concentrations that present the highest toxicity. Leaves of P. alliacea were collected in the Peruvian amazone. From this material, three types of extract (hexane, ethanolic and aqueous) were prepared, which were used in the bioassays with D. magna to find the least toxic extract. Acute toxicity bioassays with D. magna during 48 h of exposure to hexane, ethanolic, and aqueous extracts yielded median lethal concentration (LC50) values of 26.9, 230.6, and 657.9 mg L-1, respectively. The aqueous extract presented the lowest toxicity, causing minimal D. magna mortality in the range of 6.67 to 13.33% at concentrations of 10 and 100 mg L-1. This result enables the efficient use of this plant species in a sustainable manner with a minimal environmental impact for the future development of natural products for pest control.

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We study the nature of the new signal reported by LHCb in the J/ψp spectrum. Based on the S-matrix principles, we perform a minimum-bias analysis of the underlying reaction amplitude, focusing on the analytic properties that can be related to the microscopic origin of the P_{c}(4312)^{+} peak. By exploring several amplitude parametrizations, we find evidence for the attractive effect of the Σ_{c}^{+}D[over ¯]^{0} channel, which is not strong enough, however, to form a bound state.

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Population genetic data for 21 X-chromosome markers (Alu insertions and STRs) are reported for two populations (rural and urban) in Salta province (north-western Argentina). New variants are described, confirming the complexity and variability of some markers in this set. Results reveal Salta populations harbor a high Native American component, despite their self-recognized European ancestry. Notwithstanding the high genetic similarity of both populations, the rural sample seems to have maintained a larger Amerindian legacy. Data further show these X-linked markers, especially STRs, are highly informative in Salta populations and, therefore, can contribute to the development of a local database for forensic purposes in north-western Argentina.

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O objetivo do presente trabalho foi avaliar, por radiografia, histologia e densitometria óssea, o efeito da HA/ßTCP em grânulos de absorção rápida em defeito ósseo crítico em rádio de coelhos. Foram utilizados 35 coelhos machos, da raça Nova Zelândia, e realizou-se um defeito crítico nos rádios direito e esquerdo. Os animais foram distribuídos em GI, enxerto autólogo e GII, HA/ßTCP em grânulos de absorção rápida. Avaliações radiográficas foram feitas antes da cirurgia, após, aos oito, 15, 30, 45 e 60 dias e avaliações histológicas e de densitometria. Verificou-se diferença significativa ao se comparar a densidade mineral óssea obtida ao longo do tempo de estudo. Observou-se formação de rede vascular entre os poros da biocerâmica desde o primeiro tempo de avaliação, (oito dias). Foram observados tecido ósseo primário e trabéculas em tecido ósseo preexistente a partir de 30 dias da implantação. Aos 60 dias, constatou-se presença de matriz óssea em segmentos ósseos preexistentes, caracterizando a formação óssea centrípeta. A biocerâmica HA/ßTCP nanoestruturada micro-macroporosa em grânulos de absorção rápida não causa alterações microscópicas indicativas de rejeição, permite a invasão e a multiplicação celular, bem como propicia a regeneração óssea, constituindo um implante apropriado para preenchimento de falhas ósseas críticas.(AU)

The objective of this study was to evaluate the effect of HA/ ßTCP on rapid absorption granules in rabbit radiography, histology, and bone densitometry. Thirty - five male rabbits of the New Zealand breed were used and a critical defect was performed on the right and left radios. The animals were distributed in GI, autologous graft and GII HA / ßTCP in rapidly absorbed granules. Radiographic, histological, and densitometry evaluations were performed before surgery, then after eight, 15, 30, 45 and 60 days. A significant difference was found when comparing the bone mineral density obtained over the study time. Formation of vascular network between the bioceramic pores was observed by the first evaluation time, (eight days). Primary bone tissue and trabeculae were observed from preexisting bone tissue after 30 days of implantation. At 60 days, the presence of bone matrix was observed from the preexisting bone segments, characterizing the centripetal bone formation. The micro-macroporous nanocomposite HA / ßTCP of rapidly absorbing granules do not cause microscopic changes indicative of rejection, allows invasion, cell multiplication, and promotes bone regeneration, constituting an appropriate implant for filling of critical bone failures.(AU)

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In this work, compact titanium oxide layers are formed by anodization in 1 M H3PO4 aqueous electrolyte containing LiClO4. Elastic Recoil Detection Analysis (ERDA) measurements demonstrate that incorporation of lithium ions occurs during anodization, and cell-voltage transient measurements evidence the different electronic properties of Li-doped TiO2 layers. The mechanism of direct incorporation of Li during the fabrication of TiO2 layers is discussed.

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BACKGROUND: Body composition analysis has been used to investigate fat mass (FM) and bone mineral content (BMC) in children and adolescents diagnosed with HIV. Investigating the validity of bioelectrical impedance analysis (BIA) is interesting with respect to testing useful techniques for monitoring body composition in children and adolescents in clinical practice. The present study aimed to determine the validity of body composition analysis by BIA compared to dual-energy X-ray absorptiometry (DXA) and air displacement plethysmography (ADP) in children and adolescents an HIV diagnosis. METHODS: Sixty-four children and adolescents (35 females and 29 males) with a mean (SD) age of 12.22 (2.13) years and with an HIV diagnosis participated in the study. Fat-free mass (FFM), FM and body fat percentage (%BF) were obtained by BIA for comparison with DXA and ADP. Segmented FM (trunk, legs and arms), lean soft tissue mass (LSTM) (total and segmented) and BMC were obtained by BIA for comparison with DXA. RESULTS: BIA presented a clinically acceptable correlation with DXA and ADP for FFM. Values found by BIA were underestimated compared to ADP, and overestimated compared to DXA. BIA presented a clinically acceptable correlation with DXA for LSTM estimates (total and segmented parameters) in both sexes (underestimating FM and overestimating LSTM). For other components (%BF, FM and BMC), BIA had a clinically unacceptable correlation with the reference methods in both sexes. CONCLUSIONS: BIA was suitable for evaluating FFM and LSTM in children and adolescents with an HIV diagnosis. For FM, %BF and BMC, BIA was not suitable for performing an evaluation in both sexes.

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O objetivo do presente trabalho foi avaliar, por radiografia, histologia e densitometria óssea, o efeito da HA/ßTCP em grânulos de absorção rápida em defeito ósseo crítico em rádio de coelhos. Foram utilizados 35 coelhos machos, da raça Nova Zelândia, e realizou-se um defeito crítico nos rádios direito e esquerdo. Os animais foram distribuídos em GI, enxerto autólogo e GII, HA/ßTCP em grânulos de absorção rápida. Avaliações radiográficas foram feitas antes da cirurgia, após, aos oito, 15, 30, 45 e 60 dias e avaliações histológicas e de densitometria. Verificou-se diferença significativa ao se comparar a densidade mineral óssea obtida ao longo do tempo de estudo. Observou-se formação de rede vascular entre os poros da biocerâmica desde o primeiro tempo de avaliação, (oito dias). Foram observados tecido ósseo primário e trabéculas em tecido ósseo preexistente a partir de 30 dias da implantação. Aos 60 dias, constatou-se presença de matriz óssea em segmentos ósseos preexistentes, caracterizando a formação óssea centrípeta. A biocerâmica HA/ßTCP nanoestruturada micro-macroporosa em grânulos de absorção rápida não causa alterações microscópicas indicativas de rejeição, permite a invasão e a multiplicação celular, bem como propicia a regeneração óssea, constituindo um implante apropriado para preenchimento de falhas ósseas críticas.(AU)

The objective of this study was to evaluate the effect of HA/ ßTCP on rapid absorption granules in rabbit radiography, histology, and bone densitometry. Thirty - five male rabbits of the New Zealand breed were used and a critical defect was performed on the right and left radios. The animals were distributed in GI, autologous graft and GII HA / ßTCP in rapidly absorbed granules. Radiographic, histological, and densitometry evaluations were performed before surgery, then after eight, 15, 30, 45 and 60 days. A significant difference was found when comparing the bone mineral density obtained over the study time. Formation of vascular network between the bioceramic pores was observed by the first evaluation time, (eight days). Primary bone tissue and trabeculae were observed from preexisting bone tissue after 30 days of implantation. At 60 days, the presence of bone matrix was observed from the preexisting bone segments, characterizing the centripetal bone formation. The micro-macroporous nanocomposite HA / ßTCP of rapidly absorbing granules do not cause microscopic changes indicative of rejection, allows invasion, cell multiplication, and promotes bone regeneration, constituting an appropriate implant for filling of critical bone failures.(AU)

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Objetivou-se avaliar, histologicamente e por microscopia eletrônica de varredura (MEV), a evolução de defeitos críticos experimentais em rádio de coelhos preenchidos ou não com biocerâmica fosfocálcica nanoestruturada micromacro porosa em grânulos. Utilizaram-se 70 coelhos, Nova Zelândia, adultos jovens, machos, e realizou-se um defeito crítico nos rádios. Os membros constituíram os grupos: GI, biocerâmica lenta, GII, biocerâmica moderada e GIII, controle negativo. Após cada período experimental, os animais foram sacrificados, e os rádios coletados. As avaliações histológicas foram realizadas aos oito, 15, 30, 45, 60, 90 e 120 dias, e as análises de MEV aos 60, 90 e 120 dias. Histologicamente, observou-se processo de reparação óssea mais adiantado nos grupos GI e GII comparando-se ao GIII. Na MEV, constatou-se maior proporção de osso maduro e presença de ósteons secundários nos GI e GII, sendo mais evidente no GII, confirmando os achados histológicos. As cerâmicas promoveram preenchimento completo do defeito, enquanto no grupo controle houve preenchimento no centro do defeito, permanecendo espaços vazios nas laterais. Conclui-se que o emprego das biocerâmicas de absorção lenta e moderada favorece a regeneração óssea completa em defeitos críticos sendo indicadas como substituto ósseo. A maturação óssea ocorre mais precocemente quando se emprega a cerâmica de absorção moderada.(AU)

The objective was to evaluate, through histologic exam and by scanning electron microscopy (SEM), the evolution of experimental critical defects in radio or not filled with nano-structured calcium phosphate micro-macro porous bioceramic granules rabbits. We used 70 rabbits, New Zealand, young adults, males, there was a critical defect in radio. The members were the groups: GI, slow bioceramic, GII, GIII and bioceramic moderate, negative control. After each experimental period, the animals were sacrificed and the radios harvested. Histological evaluations were performed at eight, 15, 30, 45, 60, 90 and 120 days and SEM analyzes at 60, 90 and 120 days. Histologically there was bone healing process earlier in GI and GII compared to GIII. In SEM we observed a higher proportion of mature bone and presence of secondary osteons in GI and GII, being more evident in the GII, confirming the histological findings. Ceramic promoted complete filling of the defect, while the control group was filling in the center of the defect, with empty spaces remaining on the sides. In conclusion, the use of bioceramics, slow and moderate absorption favor complete bone regeneration in critical defects being indicated as a bone substitute. The maturation occurs earlier when employing the ceramic moderate absorption.(AU)

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