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Cervical length; Microbial diversity; Pessary Longitud cervical; Diversidad microbiana; Pesario Longitud cervical; Diversitat microbiana; Pessari Introduction Our objective was to compare the vaginal microbiome in low-risk and high-risk pregnant women and to explore a potential association between vaginal microbiome and preterm birth. Material and methods A pilot, consecutive, longitudinal, multicenter study was conducted in pregnant women at 18–22 weeks of gestation. Participants were assigned to one of three groups: control (normal cervix), pessary (cervical length ≤25 mm) and cerclage (cervical length ≤25 mm or history of preterm birth). Analysis and comparison of vaginal microbiota as a primary outcome was performed at inclusion and at 30 weeks of gestation, along with a follow-up of pregnancy and perinatal outcomes. We assessed the vaginal microbiome of pregnant women presenting a short cervix with that of pregnant women having a normal cervix, and compared the vaginal microbiome of women with a short cervix before and after placement of a cervical pessary or a cervical cerclage. Results The microbiome of our control cohort was dominated by Lactobacillus crispatus and inners. Five community state types were identified and microbiome diversity did not change significantly over 10 weeks in controls. On the other hand, a short cervix was associated with a lower microbial load and higher microbial richness, and was not correlated with Lactobacillus relative abundance. After intervention, the cerclage group (n = 19) had a significant increase in microbial richness and a shift towards community state types driven by various bacterial species, including Lactobacillus mulieris, unidentified Bifidobacterium or Enterococcus. These changes were not significantly observed in the pessary (n = 26) and control (n = 35) groups. The cerclage group had more threatened preterm labor episodes and poorer outcomes than the control and pessary groups. Conclusions These findings indicate that a short cervix is associated with an altered vaginal microbiome community structure. The use of a cerclage for preterm birth prevention, as compared with a pessary, was associated with a microbial community harboring a relatively low abundance of Lactobacillus, with more threatened preterm labor episodes, and with poorer clinical outcomes. This study was supported by the Instituto de Salud Carlos III/FEDER FIS PI15/02043; Beca Dexeus Mujer 2015. Francisca Yáñez was supported by a grant from ANID, BECAS Chile, N° 72190278. Zixuan Xie received a fellowship from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie Action, Innovative Training Network: FunHoMic; grant number 812969.

After exploring the potential energy surfaces of Mm CE2p (E=S-Te, M=Li-Cs, m=2, 3 and p=m-2) and Mn CE3q (E=S-Te, M=Li-Cs, n=1, 2, q=n-2) combinations, we introduce 38 new global minima containing a planar hypercoordinate carbon atom (24 with a planar tetracoordinate carbon and 14 with a planar pentacoordinate carbon). These exotic clusters result from the decoration of V-shaped CE22- and Y-shaped CE32- dianions, respectively, with alkali counterions. All these 38 systems fulfill the geometrical and electronic criteria to be considered as true planar hypercoordinate carbon systems. Chemical bonding analyses indicate that carbon is covalently bonded to chalcogens and ionically connected to alkali metals.

Early and accurate identification of cognitive and functional decline in bilingual Latino/a older adults with Alzheimer's disease and related dementias continues to be a substantial public health concern. This paper highlights the heterogeneity in the clinical expression of Alzheimer's disease among bilingual Latino/as, the clinical decisions leading to a culturally and linguistically congruent neuropsychological assessment, and the interdisciplinary, multi-setting partnerships needed to ensure a healthy longevity post-diagnosis for the patient, the caregiver, and the family. Psychologists play an important role in advocating for the best standard of care, as the patients and families endure the long journey of care with dignity and respect.

We report the global minima structures of Li8 Si8 , Li10 Si9 , and Li12 Si10 systems, in which silicon moieties maintain structural and chemical bonding characteristics similar to those of their building blocks: the aromatic clusters Td -Li4 Si4 and C2v -Li6 Si5 . Electron counting rules, chemical bonding analysis, and magnetic response properties verify the silicon unit's aromaticity persistence. This study demonstrates the feasibility of assembling silicon-based nanostructures from aromatics clusters as building blocks.

Indexación Scopus Herein, the first global minima containing a planar hexacoordinate carbon (phC) atom are reported. The fifteen structures belong to the CE3M3+ (E=S–Te and M=Li–Cs) series and satisfy both geometric and electronic criteria to be considered as a true phC. The design strategy consisted of replacing oxygen in the D3h CO3Li3+ structure with heavy and less electronegative chalcogens, inducing a negative charge on the C atom and an attractive electrostatic interaction between C and the alkali-metal cations. The chemical bonding analyses indicate that carbon is covalently bonded to three chalcogens and ionically connected to the three alkali metals. © 2021 Wiley-VCH GmbH https://onlinelibrary-wiley-com.recursosbiblioteca.unab.cl/doi/10.1002/anie.202100940

Rhamnlopids are biosurfactants with a wide range of industrial applications. The understanding of their biosynthesis and the genetic regulation of their production have impacted the development of strains that are suitable for industrial production of these biosurfactants., Summary Rhamnolipids are biosurfactants with a wide range of industrial applications that entered into the market a decade ago. They are naturally produced by Pseudomonas aeruginosa and some Burkholderia species. Occasionally, some strains of different bacterial species, like Pseudomonas chlororaphis NRRL B‐30761, which have acquired RL‐producing ability by horizontal gene transfer, have been described. P. aeruginosa, the ubiquitous opportunistic pathogenic bacterium, is the best rhamnolipids producer, but Pseudomonas putida has been used as heterologous host for the production of this biosurfactant with relatively good yields. The molecular genetics of rhamnolipids production by P. aeruginosa has been widely studied not only due to the interest in developing overproducing strains, but because it is coordinately regulated with the expression of different virulence‐related traits by the quorum‐sensing response. Here, we highlight how the research of the molecular mechanisms involved in rhamnolipid production have impacted the development of strains that are suitable for industrial production of this biosurfactant, as well as some perspectives to improve these industrial useful strains.

The oil industry needs to reduce CO2 emissions across the entire lifecycle of fossil fuels to meet environmental regulations and societal requirements and to sustain its business. With this goal in mind, this study aims to evaluate the CO2 mitigation potential of several bio-oil co-processing pathways in an oil refinery. Techno-economic analysis was conducted on different pathways and their greenhouse gas (GHG) mitigation potentials were compared. Thirteen pathways with different bio-oils, including vegetable oil (VO), fast pyrolysis oil (FPO), hydro-deoxygenated oil (HDO), catalytic pyrolysis oil (CPO), hydrothermal liquefaction oil (HTLO), and Fischer-Tropsch fuels, were analyzed. However, no single pathway could be presented as the best option. This would depend on the criteria used and the target of the co-processing route. The results obtained indicated that up to 15% of the fossil-fuel output in the refinery could be replaced by biofuel without major changes in the core activities of the refinery. The consequent reduction in CO2 emissions varied from 33% to 84% when compared with pure equivalent fossil fuels replaced (i.e., gasoline and diesel). Meanwhile, the production costs varied from 17 to 31euro/GJ (i.e., 118-213$/bbl(eq)). Co-processing with VO resulted in the lowest overall performance among the options that were evaluated while co-processing HTLO in the hydrotreatment unit and FPO in the fluid catalytic cracking unit showed the highest potential for CO2 avoidance (69% of refinery CO2 emissions) and reduction in CO2 emissions (84% compared to fossil fuel), respectively. The cost of CO2 emissions avoided for all of the assessed routes was in the range of euro99-651 per tCO(2). (c) 2020 The Authors. Biofuels, Bioproducts, and Biorefining published by Society of Chemical Industry and John Wiley & Sons, Ltd.

Through delicate tuning of the electronic structure, we report herein a rational design of seventeen new putative global minimum energy structures containing a planar tetra- or pentacoordinate carbon atom embedded in an aromatic hydrocarbon. These structures are the result of replacing three consecutive hydrogen atoms of an aromatic hydrocarbon by less electronegative groups, forming a multicenter σ-bond with the planar hypercoordinate carbon atom and participating in the π-electron delocalization. This strategy that maximizes both mechanical and electronic effects through aromatic architectures can be extended to several molecular combinations to achieve new and diverse compounds containing planar hypercoordinate carbon centers.

Extensive explorations of their potential energy surfaces, combined with high-level quantum chemical computations, strikingly show that the lowest energy structures of the (Li6 Si5 )2-5 systems consist of 2-5 Si5 6- aromatic units, surrounded by Li+ counterions, respectively. These viable gas-phase compounds are the pioneering reported cases of oligomers made by planar aromatic silicon rings. Based on the key evidence that these oligomers are energetically favored, and that their silicon rings aromaticity is thoroughly preserved, the Li6 Si5 cluster is proposed as a potential assembly unit to build silicon-lithium nanostructures, thus opening new paths to design Zintl compounds at the nanoscale level.