A finitely generated group is said to be an automata group if it admits a
faithful self-similar finite-state representation on some regular $m$-tree. We
prove that if $G$ is a subgroup of an automata ...group, then for each finitely
generated abelian group $A$, the wreath product $A \wr G$ is a subgroup of an
automata group. We obtain, for example, that $C_2 \wr (C_{2} \wr \mathbb{Z})$,
$\mathbb{Z} \wr (C_2 \wr \mathbb{Z})$, $C_2 \wr (\mathbb{Z} \wr \mathbb{Z})$,
and $\mathbb{Z} \wr (\mathbb{Z} \wr \mathbb{Z})$ are subgroups of automata
groups. In the particular case $\mathbb{Z} \wr (\mathbb{Z} \wr \mathbb{Z})$, we
prove that it is a subgroup of a two-letters automata group; this solves
Problem 15.19 - (b) of the Kourovka Notebook proposed by A. M. Brunner and S.
Sidki in 2000 8, 17.
Background:
Tibiotalocalcaneal arthrodesis is a well-established procedure to treat some hindfoot diseases. Currently, the most used implants are retrograde intramedullary nails and locking plates ...combined with lag screws, but there are few articles comparing differences regarding the complications.
Methods:
We have retrospectively analyzed the medical records and the radiographs of patients older than 18 years who underwent this procedure in our service between 2005 and 2019 through retrograde intramedullary nails or lateral locking plates and compression screws with at least 12 months of follow-up and with no history of osteomyelitis in these bones.
Results:
We evaluated a total of 67 patients; of these, 48 received retrograde intramedullary nail implants and 19 received locking plates and compression screws. The overall mean age was 48 years; the median follow-up time was 64.3 months. The complication rate was 60.4% for the intramedullary nail procedure and 52.6% for the locking plate combined with compression screws procedure.
Conclusion:
No significant differences were found in the complication rates between the 2 implants.
Level of Evidence:
Level V, Case series
A comparative study of the gene expression profile in different developmental stages of Schistosoma mansoni has been initiated based on the expressed sequence tag (EST) approach. A total of 1401 ESTs ...were generated from seven different cDNA libraries constructed from four distinct stages of the parasite life cycle. The libraries were first evaluated for their quality for a large-scale cDNA sequencing program. Most of them were shown to have less than 20% useless clones and more than 50% new genes. The redundancy of each library was also analyzed, showing that one adult worm cDNA library was composed of a small number of highly frequent genes. When comparing ESTs from distinct libraries, we could detect that most genes were present only in a single library, but others were expressed in more than one developmental stage and may represent housekeeping genes in the parasite. When considering only once the genes present in more than one library, a total of 466 unique genes were obtained, corresponding to 427 new S. mansoni genes. From the total of unique genes, 20.2% were identified based on homology with genes from other organisms, 8.3% matched S. mansoni characterized genes and 71.5% represent unknown genes.
In the face of increasing bacterial resistance to antibiotics currently in use, the search for new antimicrobial agents has received a boost in recent years, with natural products playing an ...important role in this field. In fact, several methods have been proposed to investigate the antibacterial activities of natural products. However, given that the ultimate aim is future therapeutic use as novel drugs, it is extremely necessary to elucidate their modes of action, stating the molecular effects in detail, and identifying their targets in the bacterial cell. This review analyzes the application of "omics technologies" to understand the antibacterial mechanisms of bioactive natural products, to stimulate research interest in this area and promote scientific collaborations. Some studies have been specifically highlighted herein by examining their procedures and results (targeted proteins and metabolic pathways). These approaches have the potential to provide new insights into our comprehension of antimicrobial resistance/susceptibility, creating new perspectives for the struggle against bacteria, and leading to the development of novel products in the future.
In a previous study, the Schistosoma mansoni Rho1 protein was able to
complement Rho1 null mutant Saccharomyces cerevisiae cells at
restrictive temperatures and under osmotic stress (low calcium
...concentration) better than the human homologue (RhoA). It is known that
under osmotic stress, the S. cerevisiae Rho1 triggers two distinct
pathways: activation of the membrane 1,3-b-glucan synthase enzymatic
complex and activation of the protein kinase C1 signal transduction
pathway, promoting the transcription of response genes. In the present
work the SmRho1 protein and its mutants smrhoE97P, smrho1L101T, and
smrhoE97P, L101T were used to try to clarify the basis for the
differential complementation of Rho1 knockout yeast strain by the human
and S. mansoni genes. Experiments of functional complementation in the
presence of caffeine and in the presence of the osmotic regulator
sorbitol were conducted. SmRho1 and its mutants showed a differential
complementation of the yeast cells in the presence of caffeine, since
smrhoE97P and smrhoE97P, L101T mutants showed a delay in the growth
when compared to the yeast complemented with the wild type SmRho1.
However, in the presence of sorbitol and caffeine the wild type SmRho1
and mutants showed a similar complementation phenotype, as they allowed
yeast growth in all caffeine concentrations tested.
Literature review of new genes related to osteogenesis imperfecta (OI) and update of its classification.
Literature review in the PubMed and OMIM databases, followed by selection of relevant ...references.
In 1979, Sillence et al. developed a classification of OI subtypes based on clinical features and disease severity: OI type I, mild, common, with blue sclera; OI type II, perinatal lethal form; OI type III, severe and progressively deforming, with normal sclera; and OI type IV, moderate severity with normal sclera. Approximately 90% of individuals with OI are heterozygous for mutations in the COL1A1 and COL1A2 genes, with dominant pattern of inheritance or sporadic mutations. After 2006, mutations were identified in the CRTAP, FKBP10, LEPRE1, PLOD2, PPIB, SERPINF1, SERPINH1, SP7, WNT1, BMP1, and TMEM38B genes, associated with recessive OI and mutation in the IFITM5 gene associated with dominant OI. Mutations in PLS3 were recently identified in families with osteoporosis and fractures, with X-linked inheritance pattern. In addition to the genetic complexity of the molecular basis of OI, extensive phenotypic variability resulting from individual loci has also been documented.
Considering the discovery of new genes and limited genotype-phenotype correlation, the use of next-generation sequencing tools has become useful in molecular studies of OI cases. The recommendation of the Nosology Group of the International Society of Skeletal Dysplasias is to maintain the classification of Sillence as the prototypical form, universally accepted to classify the degree of severity in OI, while maintaining it free from direct molecular reference.
Revisão da literatura sobre novos genes relacionados à osteogênese imperfeita (OI) e atualização da sua classificação.
Revisão nas bases de dados do PUBMED e OMIM com seleção de referências relevantes.
Sillence et al., em 1979, desenvolveram uma classificação dos subtipos de OI baseada em características clínicas e gravidade da doença: OI tipo I, forma leve, comum, com escleras azuladas; OI tipo II, forma perinatal letal; OI tipo III, forma grave e progressivamente deformante com esclera normal; e OI tipo IV, forma de gravidade moderada com esclera normal. Cerca de 90% dos indivíduos com OI são heterozigotos para mutações em COL1A1 e COL1A2, com padrão de herança dominante ou esporádico. A partir de 2006 foram identificadas mutações nos genes CRTAP, FKBP10, LEPRE1, PLOD2, PPIB, SERPINF1, SERPINH1, SP7, WNT1, BMP1 e TMEM38B associadas à OI recessiva e mutação em IFITM5 associada à OI dominante. Mutações em PLS3 foram identificadas recentemente em famílias com osteoporose e fraturas, com padrão de herança ligado ao X. Além da complexidade genética das bases moleculares das OI, extensa variabilidade fenotípica resultante de loci individuais também tem sido documentada.
Face à descoberta de novos genes e à correlação genótipo-fenótipo limitada, o uso de ferramentas de sequenciamento de nova geração torna-se útil no estudo molecular de casos de OI. A recomendação do Grupo de Nosologia da Sociedade Internacional de Displasias Esqueléticas é manter a classificação de Sillence como a forma prototípica e universalmente aceita para classificar o grau de gravidade na OI, e libertá-la de referência molecular direta.
Analisaram-se, neste trabalho, as mudanças ocorridas na quantidade consumidade café torrado e moído, em resposta à alteração na renda dos consumidores na regiãoSudeste do Brasil, especificamente nos ...estados de Minas Gerais, São Paulo e Rio deJaneiro, e no total das áreas da POF (Brasil). Para isso, estimaram-se elasticidadesrendado consumo desse tipo de café pelo modelo econométrico, que consiste em ajustaruma poligonal com três segmentos, para mostrar como o consumo físico per capitadesse tipo de café altera em decorrência da variação no recebimento mensal familiar percapita. Os dados foram provenientes da Pesquisa de Orçamento Familiar de 2002/2003,publicada pelo IBGE. Os resultados demonstraram elasticidade-renda maior que zero emenor que um para café torrado e moído, o que indica que este produto é consideradoum bem normal nas regiões analisadas, ou seja, uma variação na renda do consumidoracarretará uma variação menos que proporcional no consumo de café.
•NaHCO3 treatment contributes to increase fibre density, stiffness and reduce thermal stability.•Epoxy composites achieve higher tensile and flexural strength than polyester composites.•Polyester ...composites reach higher tensile and flexural modulus than epoxy composites.•The alkaline treatment does not affect the mechanical strength of the composites.•Higher tensile and flexural moduli are obtained in 96 or 168 h of alkaline exposure.
This work evaluates a new eco-friendly surface treatment method for coir fibres based on sodium bicarbonate (NaHCO3). The fibres are treated with 10 wt% NaHCO3 solution for different periods of time (24, 96 and 168 h). A 2141 Full Factorial Design is established to investigate the effect of the type of matrix (epoxy and polyester) and treatment time (24, 96 and 168 h) on the mechanical properties of coir fibre composites. X-Ray diffraction (XRD) analysis reveals that the treatment does not promote a complete change of cellulose-I into cellulose-II. However, the degradation of hemicellulose and pectin of the fibre surface is evidenced by the thermogravimetric (TGA) curves. The chemical treatment contributes to increase the fibre density and to reduce its thermal stability. Single fibre tensile tests reveal a gradual increase in the elastic modulus attributed to the treatment time factor. Epoxy composites presented higher tensile and flexural strength in comparison to polyester composites, which exhibit higher tensile and flexural modulus. The alkaline treatment does not affect the mechanical strength of the composites. However, higher tensile and flexural moduli are obtained when the treatment time increases to 96 or 168 h. The proposed treatment proves to be feasible and efficient to increase the stiffness of coir fibre composites, besides being less damaging to the environment after disposal when compared to strongly alkaline solutions such as NaOH.
To avoid the intrinsic difficulties regarding the characterization of wood (i.e., different applications in different directions), various normative documents present the relationships between ...properties; the Brazilian standard is of particular interest in this regard, because Brazil has a huge diversity of tree species from tropical forests, usually used in construction. In view of this, this research aimed to propose a new list of properties to be inserted in future versions of the Brazilian standards in order to help identify the species shear strength. It is expected that there is a correlation between the characteristic values of flexural strength (fm,k) and shear strength in the direction parallel to the wood fibers (fv,0,k), leading to models that make it possible to estimate one of the properties if the other is known, which was the main objective of this research. After finding a strong correlation between the properties, various regression models were evaluated. It can be concluded that the linear model composed only by the angular coefficient (equation with only one variable) presented a determination coefficient of 76.45%, which shows the good precision achieved in the estimation of one of the two variables compared if the other is known. Additionally, an attempt was made to define which probability distribution represents the resistance data by applying maximum likelihood (MLE), concluding that there is little difference between the representation by the normal distribution and the generalized extreme value (GEV) distribution. Another approach was to define the undermining coefficient to ensure the reliability of the prediction equation by the experiment-based calibration methodology defined by Eurocode.
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