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Introduction Previous work has shown that exposure of electrospray droplets to ethyl acetate produce spectra with more intense protein signal, as well as protein envelopes shifted toward higher charge states . This is of specific interest when carrying out DESI-MS analysis, as the technique struggles to analyze proteins larger than 25 kDa in size due to poor dissolution and adduction. . The mechanism by which ethyl acetate improves responses was studied by analyzing protein molecules in atmospheres modified with ethyl acetate and related polar organic compounds, and an analogue series of esters with increasing chain lengths. Methods All spectra were collected using a Thermo LTQ XL mass spectrometer. ESI samples were 2.5 μM cytochrome C, myoglobin or lysozyme in 80% methanol with 0.1% formic acid or in aqueous 100mM ammonium acetate. A polypropylene enclosure for introduction of additive to the atmospheric region around the ion source and transfer tube was constructed . Liquid additives were introduced at a controlled, continuous, flow rate of 70 μL/min onto a flash chromatography pad acting as a reservoir inside of the enclosure. The additive was allowed to evaporate from the reservoir pad to saturate the ionization region. Relative changes in signals upon vapor additions were reported as the ratio to enclosed signal without vapor modification. Preliminary Data Our results indicate dependence on the alkyl chain length on either side of the ester functional group. By increasing the alkyl chain length of alcohol and carboxylic acid precursors, the hydrophobicity of esters also increases. Longer alkyl chains proton affinities of these molecules. Proteins were analyzed from denaturing conditions and ionization is believed to occur through the chain ejection model (CEM). We suggest that the increasing hydrophobicity of the esters may increasingly aid in lowering the energy barrier of transfer of the denatured protein from the solvated state in bulk droplet to the gas phase. This might be a consequence of the formation of a condensed ester on the evaporative cooled microdroplet, or a gas phase interaction. The degree of improvement when modifying the ionization region with esters initially shows little to no increase when using those with smaller alkyl chains (C3, C4). With longer chains (C7), however, dramatic improvements in protein signal can be observed. This is particularly evident when analyzing higher charge state peaks corresponding to more unfolded protein populations, such peaks corresponding to more unfolded protein populations. This effect may be due to competition between vapor pressure of the atmospheric modifiers and hydrophobic interactions between the modifier and ejecting protein. Vapor pressure drastically decreases between ethyl acetate to longer chain esters such as butyl acetate. Additional heating of the pad will be investigated to compensate for this trade-off. . With even longer chain esters, such as ethyl heptanoate, we see a greater improvement, indicating that their increased hydrophobic character and resultant analyte interactions is more favorable. As well, the improved signal observed for higher charge state peaks consequently increases the protein average charge state. Novel Aspect Vapor addition of esters with increasing chain lengths to the atmospheric ionization region improve protein detection by electrospray-based methods 

Decision-making is a cognitive process involving working memory, executive function, and attention. However, the connectivity of large-scale brain networks during decision-making is not well understood. This is because gaining access to large-scale brain networks in humans is still a novel process. Here, we used SEEG (stereoelectroencephalography) to record neural activity from the default mode network (DMN), dorsal attention network (DAN), and frontoparietal network (FN) in ten humans while they performed a gambling task in the form of the card game, “War”. By observing these networks during a decision-making period, we related the activity of and connectivity between these networks. In particular, we found that gamma band activity was directly related to a participant’s ability to bet logically, deciding what betting amount would result in the highest monetary gain or lowest monetary loss throughout a session of the game. We also found connectivity between the DAN and the relation to a participant’s performance. Specifically, participants with higher connectivity between and within these networks had higher earnings. Our preliminary findings suggest that connectivity and activity between these networks are essential during decision-making. 

Background Despite more than 60 years of research, the etiology of bacterial vaginosis (BV) remains controversial. In this pilot study, we used shotgun metagenomic sequencing to characterize vaginal microbial community changes before the development of incident BV (iBV). Methods A cohort of African American women with a baseline healthy vaginal microbiome (no Amsel criteria, Nugent score 0–3 with no Gardnerella vaginalis morphotypes) were followed for 90 days with daily self-collected vaginal specimens for iBV (≥2 consecutive days of a Nugent score of 7–10). Shotgun metagenomic sequencing was performed on select vaginal specimens from 4 women, every other day for 12 days before iBV diagnosis. Sequencing data were analyzed through Kraken2 and bioBakery 3 workflows, and specimens were classified into community state types. Quantitative polymerase chain reaction was performed to compare the correlation of read counts with bacterial abundance. Results Common BV-associated bacteria such as G. vaginalis , Prevotella bivia , and Fannyhessea vaginae were increasingly identified in the participants before iBV. Linear modeling indicated significant increases in G. vaginalis and F . vaginae relative abundance before iBV, whereas the relative abundance of Lactobacillus species declined over time. The Lactobacillus species decline correlated with the presence of Lactobacillus phages. We observed enrichment in bacterial adhesion factor genes on days before iBV. There were also significant correlations between bacterial read counts and abundances measured by quantitative polymerase chain reaction. Conclusions This pilot study characterizes vaginal community dynamics before iBV and identifies key bacterial taxa and mechanisms potentially involved in the pathogenesis of iBV. 

Introduction The effect of testosterone (T) therapy on the vaginal microbiota of transgender men (TGM) is not well characterised, although one cross-sectional study comparing the vaginal microbiota of cisgender women to TGM on T≥1 year found that, in 71% of the TGM, the vaginal microbiota was less likely to be Lactobacillus -dominated and more likely to be enriched with >30 other bacterial species, many associated with bacterial vaginosis (BV). This prospective study aims to investigate changes in the composition of the vaginal microbiota over time in TGM who retain their natal genitalia (ie, vagina) and initiate T. In addition, we will identify changes in the vaginal microbiota preceding incident BV (iBV) in this cohort while investigating behavioural factors, along with hormonal shifts, which may be associated with iBV. Methods and analysis T-naïve TGM who have not undergone gender-affirming genital surgery with normal baseline vaginal microbiota (ie, no Amsel criteria, normal Nugent Score with no Gardnerella vaginalis morphotypes) will self-collect daily vaginal specimens for 7 days prior to initiating T and for 90 days thereafter. These specimens will be used for vaginal Gram stain, 16S rRNA gene sequencing and shotgun metagenomic sequencing to characterise shifts in the vaginal microbiota over time, including development of iBV. Participants will complete daily diaries on douching, menses and behavioural factors including sexual activity during the study. Ethics and dissemination This protocol is approved through the single Institutional Review Board mechanism by the University of Alabama at Birmingham. External relying sites are the Louisiana State University Health Sciences Center, New Orleans Human Research Protection Program and the Indiana University Human Research Protection Program. Study findings will be presented at scientific conferences and peer-reviewed journals as well as shared with community advisory boards at participating gender health clinics and community-based organisations servicing transgender people. Registration details Protocol # IRB-300008073. 

Purpose This study aims to present theory, practice and original research findings to support the proposition that broad enquiry and problem-based learning (EPBL) approaches provide an appropriate pedagogical lens for sustainability educators to develop the knowledge and skills needed to work effectively within mission-oriented innovation policy (MIP) environments. Design/methodology/approach The research study comprised four elements, each of which used different research methods. The first element involved a literature review mapping the synergies between MIP and EPBL; the second element piloted the use of EPBL for undergraduate modules related to sustainability challenges; the third element involved external stakeholders in the co-creation of a postgraduate programme that brought together innovation and sustainability, with EPBL fundamental to the design and development; the fourth element curated and comparatively analysed international cases of EPBL in the context of MIP, and sustainability challenges in particular, highlighting the versatility of EPBL and the importance of creativity in EPBL design and implementation. Findings The systematic literature review reveals synergies between the key features of EPBL and defining characteristics of MIP, indicating the relevance of applying EPBL to support MIP. Two in situ pilots generated 13 recommendations on the benefits and operational challenges of applying EPBL. These recommendations informed the design and development of a postgraduate programme, involving a transdisciplinary consultation process with key industrial and societal stakeholders. Comparative analysis of four international case studies describing EPBL applied in practice in different international settings show there is no “one size fits all”. Instead, the application of EPBL to different sustainability challenges and for different learner groups demonstrates the versatility of the pedagogical approach and the creativity of the sustainability educators. Originality/value A discourse around the appropriate pedagogical methods and teaching/learning practice to equip the current and future workforce with the knowledge and skills to respond to MIP and global sustainability challenges is nascent but emerging. This paper makes a scientific and practical contribution to the discourse. The authors show how EPBL can underpin the design of programmes to provide learners with the knowledge and skills to support organisations working effectively within an MIP context, especially addressing sustainability challenges. The authors provide recommendations for educators seeking to embed EPBL within their curriculum and call for external stakeholders to proactively engage with educators to co-create programmes with context-specific outcomes.