Blanding’s Turtle (\u3ci\u3eEmydoidea blandingii\u3c/i\u3e): Species Conservation Assessment

The primary goal in development of at-risk species conservation assessments is to compile biological and ecological information that may assist conservation practitioners in making decisions regarding the conservation of species of interest. The Nebraska Natural Legacy Project recognizes the Blanding’s turtle (Emydoidea blandingii) as a Tier I at-risk species. Some general management recommendations are made here regarding Blanding’s turtles; however, conservation practitioners will need to use professional judgment to make specific management decisions based on objectives, location, and a multitude of variables. This resource was designed to share available knowledge of this at-risk turtle that will aid in the decision-making process or in identifying research needs to benefit the species. Species conservation assessments will need to be updated as relevant scientific information becomes available and/or conditions change. The Nebraska Natural Legacy Project focuses efforts in the state’s Biologically Unique Landscapes, but it is recommended that whenever possible, practitioners make considerations for a species throughout its range in order to increase the outcome of successful conservation efforts. Criteria for selection as Tier I Ranked as imperiled or vulnerable in all but one state in its range Trends since 2005 in NE Stable Range in NE Primarily Sandhills marshes, very locally in eastern portion of state Habitat Requires proximity to water; Sandhills fens, Sandhills freshwater marsh, northern cordgrass wet prairie, small tributaries, Sandhills prairies (upland habitat), marshes and oxbows in eastern portion of state Threats Habitat fragmentation and loss of wetlands in eastern part of range; vehicle mortality; collection for pet trade Climate Change Vulnerability Index: Not Vulnerable; presumed stable Research/Inventory Continue surveys along eastern edge of range within the state as populations recover from extreme weather events of 2019; Continue population monitoring in the Sandhills region and areas further south and west in the state; Collect DNA samples for population research Landscapes Cherry County Wetlands, Dismal River Headwaters, Elkhorn Confluence, Elkhorn River Headwaters, Lower Loup Rivers, Lower Platte River, Middle Niobrara, Upper Loup Rivers and Tributaries According to the last review in 2020, the subnational conservation status rank for Blanding’s turtle is S4 (‘apparently secure’), indicating that the species is “at a fairly low risk of extirpation in the state due to an extensive range and/or many populations or occurrences, but with possible cause for some concern as a result of local recent declines, threats, or other factors (Master et al. 2012).” The global conservation rank is G4 (NatureServe 2020). The definition of G4 is similar to the definition of S4 but uses the world rather than the state as a geographic reference and refers to the risk of extinction as opposed to extirpation. Blanding’s turtle is less secure in each of the other states/provinces in its range compared to Nebraska. It was included on the Tier 1 list of at-risk species (Schneider et al 2018) because it met the criterion of being imperiled or vulnerable in all but one state it its range

Timber Rattlesnake (\u3ci\u3eCrotalus horridus\u3c/i\u3e): A Species Conservation Assessment for The Nebraska Natural Legacy Project

The primary goal in the development of at-risk species conservation assessments is to compile biological and ecological information that may assist conservation practitioners in making decisions regarding the conservation of species of interest. The Nebraska Natural Legacy Project recognizes the timber rattlesnake (Crotalus horridus) as a Tier 1 at-risk species. Provided here are general management recommendations regarding timber rattlesnakes. Conservation practitioners will need to use their professional judgment for management decisions based on objectives, location, and site-specific conditions. Based on the body of literature and available data, this species conservation assessment provides an overview of our current knowledge of timber rattlesnakes and may aid in decision-making for their conservation or in identifying research needs for the benefit of the species. Species conservation assessments will need to be updated as new scientific information becomes available. The Nebraska Natural Legacy Project focuses efforts in the state’s Biologically Unique Landscapes (BULs), but it is also recommended that whenever possible, practitioners make considerations for a species throughout its range in order to increase the success of conservation efforts

Space science experimentation automation and support

This paper outlines recent work done at the NASA Ames Artificial Intelligence Research Laboratory on automation and support of science experiments on the US Space Shuttle in low earth orbit. Three approaches to increasing the science return of these experiments using emerging automation technologies are described: remote control (telescience), science advisors for astronaut operators, and fully autonomous experiments. The capabilities and limitations of these approaches are reviewed

Production of functionalized polyhydroxyalkanoates by genetically modified Methylobacterium extorquens strains

<p>Abstract</p> <p>Background</p> <p>Methylotrophic (methanol-utilizing) bacteria offer great potential as cell factories in the production of numerous products from biomass-derived methanol. Bio-methanol is essentially a non-food substrate, an advantage over sugar-utilizing cell factories. Low-value products as well as fine chemicals and advanced materials are envisageable from methanol. For example, several methylotrophic bacteria, including <it>Methylobacterium extorquens</it>, can produce large quantities of the biodegradable polyester polyhydroxybutyric acid (PHB), the best known polyhydroxyalkanoate (PHA). With the purpose of producing second-generation PHAs with increased value, we have explored the feasibility of using <it>M. extorquens </it>for producing functionalized PHAs containing C-C double bonds, thus, making them amenable to future chemical/biochemical modifications for high value applications.</p> <p>Results</p> <p>Our proprietary <it>M. extorquens </it>ATCC 55366 was found unable to yield functionalized PHAs when fed methanol and selected unsaturated carboxylic acids as secondary substrates. However, cloning of either the <it>phaC1 </it>or the <it>phaC2 </it>gene from <it>P. fluorescens </it>GK13, using an inducible and regulated expression system based on cumate as inducer (the cumate switch), yielded recombinant <it>M. extorquens </it>strains capable of incorporating modest quantities of C-C double bonds into PHA, starting from either C6= and/or C8=. The two recombinant strains gave poor results with C11=. The strain containing the <it>phaC2 </it>gene was better at using C8= and at incorporating C-C double bonds into PHA. Solvent fractioning indicated that the produced polymers were PHA blends that consequently originated from independent actions of the native and the recombinant PHA synthases.</p> <p>Conclusions</p> <p>This work constitutes an example of metabolic engineering applied to the construction of a methanol-utilizing bacterium capable of producing functionalized PHAs containing C-C double bonds. In this regard, the PhaC2 synthase appeared superior to the PhaC1 synthase at utilizing C8= as source of C-C double bonds and at incorporating C-C double bonds into PHA from either C6= or C8=. The <it>M. ex-phaC2 </it>strain is, therefore, a promising biocatalyst for generating advanced (functionalized) PHAs for future high value applications in various fields.</p

Development of RTM and powder prepreg resins for subsonic aircraft primary structures

Dow developed a thermoset resin which could be used to produce composites via the RTM process. The composites formed are useful at 200 F service temperatures after moisture saturation, and are tough systems that are suitable for subsonic aircraft primary structure. At NASA's request, Dow also developed a modified version of the RTM resin system which was suitable for use in producing powder prepreg. In the course of developing the RTM and powder versions of these resins, over 50 different new materials were produced and evaluated

PI in the sky: The astronaut science advisor on SLS-2

The Astronaut Science Advisor (ASA, also known as Principal-Investigator-in-a-Box) is an advanced engineering effort to apply expert systems technology to experiment monitoring and control. Its goal is to increase the scientific value of information returned from experiments on manned space missions. The first in-space test of the system will be in conjunction with Professor Larry Young's (MIT) vestibulo-ocular 'Rotating Dome' experiment on the Spacelab Life Sciences 2 mission (STS-58) in the Fall of 1993. In a cost-saving effort, off-the-shelf equipment was employed wherever possible. Several modifications were necessary in order to make the system flight-worthy. The software consists of three interlocking modules. A real-time data acquisition system digitizes and stores all experiment data and then characterizes the signals in symbolic form; a rule-based expert system uses the symbolic signal characteristics to make decisions concerning the experiment; and a highly graphic user interface requiring a minimum of user intervention presents information to the astronaut operator. Much has been learned about the design of software and user interfaces for interactive computing in space. In addition, we gained a great deal of knowledge about building relatively inexpensive hardware and software for use in space. New technologies are being assessed to make the system a much more powerful ally in future scientific research in space and on the ground

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

Total synthesis, isolation, surfactant properties, and biological evaluation of ananatosides and related macrodilactone-containing rhamnolipids

Rhamnolipids are a specific class of microbial surfactants, which hold great biotechnological and therapeutic potential. However, their exploitation at the industrial level is hampered because they are mainly produced by the opportunistic pathogenPseudomonas aeruginosa. The non-human pathogenic bacteriumPantoea ananatisis an alternative producer of rhamnolipid-like metabolites containing glucose instead of rhamnose residues. Herein, we present the isolation, structural characterization, and total synthesis of ananatoside A, a 15-membered macrodilactone-containing glucolipid, and ananatoside B, its open-chain congener, from organic extracts ofP. ananatis. Ananatoside A was synthesized through three alternative pathways involving either an intramolecular glycosylation, a chemical macrolactonization or a direct enzymatic transformation from ananatoside B. A series of diasteroisomerically pure (1→2), (1→3), and (1→4)-macrolactonized rhamnolipids were also synthesized through intramolecular glycosylation and their anomeric configurations as well as ring conformations were solved using molecular modeling in tandem with NMR studies. We show that ananatoside B is a more potent surfactant than its macrolide counterpart. We present evidence that macrolactonization of rhamnolipids enhances their cytotoxic and hemolytic potential, pointing towards a mechanism involving the formation of pores into the lipidic cell membrane. Lastly, we demonstrate that ananatoside A and ananatoside B as well as synthetic macrolactonized rhamnolipids can be perceived by the plant immune system, and that this sensing is more pronounced for a macrolide featuring a rhamnose moiety in its native1C4conformation. Altogether our results suggest that macrolactonization of glycolipids can dramatically interfere with their surfactant properties and biological activity

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