Morphological traits as indicators of sexual dimorphism in Prairie Rattlesnakes (\u3ci\u3eCrotalus viridis\u3c/i\u3e)

As humans encroach into areas inhabited by predators, the potential of human-predator confrontations increases and the predators become regarded as dangerous pests. Predators exert a measure of population control over pest species such as small rodents, as well as limit the quantity and scope of diseases (e.g. spread of Hantavirus by these prey species). Control of these small rodent pest species can be aided by conserving and managing their predators like rattlesnakes (Crotalus spp). Management of any population requires detailed information on population composition and the ability to determine the key information (especially age and sex) for each individual quickly and with high accuracy. To determine the sex of a snake in the field, traditionally, a probe or forceful expulsion of the hemipenes are used. In the hands of a person unskilled in field herpetology, these methods can potentially be painful to the snake, as well as place the observer in unnecessary danger. The goal of this study was to develop a less invasive field method of determining sex for any life stage in Prairie Rattlesnakes (C. viridis) using morphological characteristics that are commonly collected. Snout-vent length (SVL), and absolute and relative measures of tail length (TL, TL/SVL), rattle length (RL, RL/SVL), number of subcaudal scales (SS, SS/SVL), and number of dorsal saddle patterns (DS, DS/SVL) were examined within and across life stages of a C. viridis populationnear Ulysses, Kansas, USA, collected from 2012-2015 to facilitate a safe working environment for a prairie restoration project. SVL, , RL, and DS as well ass RL/SVL and DS/SVL did not differ between sexes within and across life stages. TL,SS,TL/SVL and SS/SVL did not differ between male and female neonates and juveniles, but were, on average, larger in adult males than females. Regression tree analysis, however, indicated that TL and SS as well as TL/SVL and SS/SVL are not very reliable for sex determination of adult snakes. Yet, if used in conjunction with other reliable methods, such as palpation of the ventral area of a snake to determine gravidity, both absolute and relative measures of tail length and number of subcaudal scales are viable alternatives to the more invasive methods currently in use

Structurally-informed Mutagenesis of a Stereochemically Promiscuous Aldolase Produces Mutants that Catalyse the Diastereoselective Syntheses of all Four Stereoisomers of 3-Deoxy-Hexulosonic acid

[Image: see text] A 2-keto-3-deoxygluconate aldolase from the hyperthermophile Sulfolobus solfataricus catalyzes the nonstereoselective aldol reaction of pyruvate and d-glyceraldehyde to produce 2-keto-3-deoxygluconate (d-KDGlc) and 2-keto-3-deoxy-d-galactonate (d-KDGal). Previous investigations into curing the stereochemical promiscuity of this hyperstable aldolase used high-resolution structures of the aldolase bound to d-KDGlc or d-KDGal to identify critical amino acids involved in substrate binding for mutation. This structure-guided approach enabled mutant variants to be created that could stereoselectively catalyze the aldol reaction of pyruvate and natural d-glyceraldehyde to selectively afford d-KDGlc or d-KDGal. Here we describe the creation of two further mutants of this Sulfolobus aldolase that can be used to catalyze aldol reactions between pyruvate and non-natural l-glyceraldehyde to enable the diastereoselective synthesis of l-KDGlc and l-KDGal. High-resolution crystal structures of all four variant aldolases have been determined (both unliganded and liganded), including Variant 1 with d-KDGlc, Variant 2 with pyruvate, Variant 3 with l-KDGlc, and Variant 4 with l-KDGal. These structures have enabled us to rationalize the observed changes in diastereoselectivities in these variant-catalyzed aldol reactions at a molecular level. Interestingly, the active site of Variant 4 was found to be sufficiently flexible to enable catalytically important amino acids to be replaced while still retaining sufficient enzymic activity to enable production of l-KDGal

Extracellular DNA release, quorum sensing, and PrrF1/F2 small RNAs are key players in Pseudomonas aeruginosa tobramycin-enhanced biofilm formation

Biofilms are structured microbial communities that are the leading cause of numerous chronic infections which are difficult to eradicate. Within the lungs of individuals with cystic fibrosis (CF), Pseudomonas aeruginosa causes persistent biofilm infection that is commonly treated with aminoglycoside antibiotics such as tobramycin. However, sublethal concentrations of this aminoglycoside were previously shown to increase biofilm formation by P. aeruginosa, but the underlying adaptive mechanisms still remain elusive. Herein, we combined confocal laser scanning microscope analyses, proteomics profiling, gene expression assays and phenotypic studies to unravel P. aeruginosa potential adaptive mechanisms in response to tobramycin exposure during biofilm growth. Under this condition, we show that the modified biofilm architecture is related at least in part to increased extracellular DNA (eDNA) release, most likely as a result of biofilm cell death. Furthermore, the activity of quorum sensing (QS) systems was increased, leading to higher production of QS signaling molecules. We also demonstrate upon tobramycin exposure an increase in expression of the PrrF small regulatory RNAs, as well as expression of iron uptake systems. Remarkably, biofilm biovolumes and eDNA relative abundances in pqs and prrF mutant strains decrease in the presence of tobramycin. Overall, our findings offer experimental evidences for a potential adaptive mechanism linking PrrF sRNAs, QS signaling, biofilm cell death, eDNA release, and tobramycin-enhanced biofilm formation in P. aeruginosa. These specific adaptive mechanisms should be considered to improve treatment strategies against P. aeruginosa biofilm establishment in CF patients’ lungs

High- versus low-intensity interventions for perinatal depression delivered by non-specialist primary maternal care providers in Nigeria: cluster randomised controlled trial (the EXPONATE trial)

Background: Contextually appropriate interventions delivered by primary maternal care providers might be effective in reducing the treatment gap for perinatal depression.Aim: To compare a high intensity psychological intervention with a low intensity enhanced usual care in the treatment of perinatal depression.Methods: This cluster randomized clinical trial was conducted in Ibadan, Nigeria between June 18, 2013 and December 11, 2015. Twenty-nine maternal care clinics were randomized to either high intensity (HIT, n=15) or low intensity (LIT, n=14) treatment. Pregnant women, registering for antenatal care, assessed to have DSM-IV major depression, received either enhanced usual care delivered by providers using the WHO Mental Health Gap Action Programme – Intervention Guide (LIT arm) or 8 weekly structured problem solving prenatal sessions delivered within a stepped care model (HIT arm). Primary outcome was recovery from depression 6 months postpartum (score < 6 on the Edinburgh Postnatal Depression Scale, (EPDS). Results: There were 686 participants, 452 and 234 in HIT and LIT arms, respectively, with both groups similar at baseline. Follow-up assessments, completed on 85%, showed recovery rates of 70% in the HIT arm and 66% in the LIT arm: adjusted risk difference 4% (95%CI: -4·1%, 12·0%), adjusted odds ratio 1·12 (95%CI: 0·73, 1·72). HIT was more effective among women with higher baseline EPDS scores (adjusted interaction OR 2·29, 95%CI 1·01, 5·20).Conclusions: Except among more severely depressed perinatal women, we found no strong evidence to recommend high intensity in preference to low intensity psychological intervention in routine primary maternal care

Guilt, shame, and postpartum infant feeding outcomes: A systematic review

Abstract Negative maternal affect (e.g., depression and anxiety) has been associated with shorter breastfeeding duration and poorer breastfeeding intention, initiation, and exclusivity. Other affective states, including guilt and shame, have been linked with formula feeding practice, though existing literature has yet to be synthesised. A narrative synthesis of quantitative data and a framework synthesis of qualitative and quantitative data were conducted to explore guilt and/or shame in relation to infant feeding outcomes. Searches were conducted on the DISCOVER database between December 2017 and March 2018. The search strategy was rerun in February 2020, together yielding 467 studies. The study selection process identified 20 articles, published between 1997 and 2017. Quantitative results demonstrated formula feeders experienced guilt more commonly than breastfeeding mothers. Formula feeders experienced external guilt most commonly associated with healthcare professionals, whereas breastfeeding mothers experienced guilt most commonly associated with peers and family. No quantitative literature examined shame in relation to infant feeding outcomes, warranting future research. The framework synthesis generated four distinct themes which explored guilt and/or shame in relation to infant feeding outcomes: ‘underprepared and ineffectively supported’, ‘morality and perceived judgement’ (breastfeeding), ‘frustration with infant feeding care’ and ‘failures, fears and forbidden practice’ (formula feeding). Both guilt and shame were associated with self‐perception as a bad mother and poorer maternal mental health. Guilt and shame experiences were qualitatively different in terms of sources and outcomes, dependent on infant feeding method. Suggestions for tailored care to minimise guilt and shame, while supporting breastfeeding, are provided

Vulnerability to high risk sexual behaviour (HRSB) following exposure to war trauma as seen in post-conflict communities in eastern uganda: a qualitative study

<p>Abstract</p> <p>Background</p> <p>Much of the literature on the relationship between conflict-related trauma and high risk sexual behaviour (HRSB) often focuses on refugees and not mass in-country displaced people due to armed conflicts. There is paucity of research about contexts underlying HRSB and HIV/AIDS in conflict and post-conflict communities in Uganda. Understanding factors that underpin vulnerability to HRSB in post-conflict communities is vital in designing HIV/AIDS prevention interventions. We explored the socio-cultural factors, social interactions, socio-cultural practices, social norms and social network structures that underlie war trauma and vulnerability to HRSB in a post-conflict population.</p> <p>Methods</p> <p>We did a cross-sectional qualitative study of 3 sub-counties in <it>Katakwi </it>district and 1 in <it>Amuria </it>in Uganda between March and May 2009. We collected data using 8 FGDs, 32 key informant interviews and 16 in-depth interviews. We tape-recorded and transcribed the data. We followed thematic analysis principles to manage, analyse and interpret the data. We constantly identified and compared themes and sub-themes in the dataset as we read the transcripts. We used illuminating verbatim quotations to illustrate major findings.</p> <p>Results</p> <p>The commonly identified HRSB behaviours include; transactional sex, sexual predation, multiple partners, early marriages and forced marriages. Breakdown of the social structure due to conflict had resulted in economic destruction and a perceived soaring of vulnerable people whose propensity to HRSB is high. Dishonour of sexual sanctity through transactional sex and practices like incest mirrored the consequence of exposure to conflict. HRSB was associated with concentration of people in camps where idleness and unemployment were the norm. Reports of girls and women who had been victims of rape and defilement by men with guns were common. Many people were known to have started to display persistent worries, hopelessness, and suicidal ideas and to abuse alcohol.</p> <p>Conclusions</p> <p>The study demonstrated that conflicts disrupt the socio-cultural set up of communities and destroy sources of people's livelihood. Post-conflict socio-economic reconstruction needs to encompass programmes that restructure people's morals and values through counselling. HIV/AIDS prevention programming in post-conflict communities should deal with socio-cultural disruptions that emerged during conflicts. Some of the disruptions if not dealt with, could become normalized yet they are predisposing factors to HRSB. Socio-economic vulnerability as a consequence of conflict seemed to be associated with HRSB through alterations in sexual morality. To pursue safer sexual health choices, people in post-conflict communities need life skills.</p

The Complete Genome Sequence of Fibrobacter succinogenes S85 Reveals a Cellulolytic and Metabolic Specialist

Fibrobacter succinogenes is an important member of the rumen microbial community that converts plant biomass into nutrients usable by its host. This bacterium, which is also one of only two cultivated species in its phylum, is an efficient and prolific degrader of cellulose. Specifically, it has a particularly high activity against crystalline cellulose that requires close physical contact with this substrate. However, unlike other known cellulolytic microbes, it does not degrade cellulose using a cellulosome or by producing high extracellular titers of cellulase enzymes. To better understand the biology of F. succinogenes, we sequenced the genome of the type strain S85 to completion. A total of 3,085 open reading frames were predicted from its 3.84 Mbp genome. Analysis of sequences predicted to encode for carbohydrate-degrading enzymes revealed an unusually high number of genes that were classified into 49 different families of glycoside hydrolases, carbohydrate binding modules (CBMs), carbohydrate esterases, and polysaccharide lyases. Of the 31 identified cellulases, none contain CBMs in families 1, 2, and 3, typically associated with crystalline cellulose degradation. Polysaccharide hydrolysis and utilization assays showed that F. succinogenes was able to hydrolyze a number of polysaccharides, but could only utilize the hydrolytic products of cellulose. This suggests that F. succinogenes uses its array of hemicellulose-degrading enzymes to remove hemicelluloses to gain access to cellulose. This is reflected in its genome, as F. succinogenes lacks many of the genes necessary to transport and metabolize the hydrolytic products of non-cellulose polysaccharides. The F. succinogenes genome reveals a bacterium that specializes in cellulose as its sole energy source, and provides insight into a novel strategy for cellulose degradation