Expression, Purification, Crystallization and Preliminary X-Ray Analysis of \u3cem\u3ePseudomonas aeuginosa\u3c/em\u3e AlgX

AlgX is a periplasmic protein required for the production of the exopolysaccharide alginate in Pseudomonas sp. and Azotobacter vinelandii. AlgX has been overexpressed and purified and diffraction-quality crystals have been grown using iterative seeding and the hanging-drop vapor-diffusion method. The crystals grew as flat plates with unit-cell parameters a=46.4, b=120.6, c=86.9Å, β=95.7°. The cyrstals exhibited the symmetry of space group P21 and diffracted to a minimimum d-spacing of 2.1Å. On the basis of the Matthews coefficient (VM=2.25Å3 Da-1), two molecules were estimated to be present in the asymmetric unit

The Orbital Light Curve of Aquila X-1

We obtained R- and I-band CCD photometry of the soft X-ray transient/neutron- star binary Aql X-1 in 1998 June while it was at quiescence. We find that its light curve is dominated by ellipsoidal variations, although the ellipsoidal variations are severely distorted and have unequal maxima. After we correct for the contaminating flux from a field star located only 0.46" away, the peak-to-peak amplitude of the modulation is ~0.25 mag in the R band, which requires the orbital inclination to be greater than 36 degrees. The orbital period we measure is consistent with the 18.95 h period measured by Chevalier & Ilovaisky (1998). During its outbursts the light curve of Aql X-1 becomes single humped. The outburst light curve observed by Garcia et al. (1999) agrees in phase with our quiescent light curve. We show that the single humped variation is caused by a ``reflection effect,'' that is, by heating of the side of the secondary star facing towards the neutron star.Comment: 18 manuscript pages, 7 figures; accepted by A

A prospective controlled study of the efficacy of short-term anticoagulation therapy in patients with deep vein thrombosis of the lower extremity

AbstractPurpose: The long-term risk for recurrent deep venous thrombosis (DVT) and the incidence of post-thrombotic syndrome (PTS) after long-term anticoagulation (LTA) therapy have been widely debated. In this study, we compare the results of short-term anticoagulation therapy versus conventional LTA therapy in patients with DVT of the lower extremity. Methods: Baseline assessments of DVT symptoms and risk factors were recorded in 105 patients. Diagnosis was made using duplex ultrasound/venography. Patients were sequentially assigned to 1 of the following treatment protocols: (A) conventional LTA therapy, which included initial intravenous standard heparin followed by warfarin on days 3 to 5 and was continued for 3 months for patients without pulmonary embolism (PE); or (B) short-term therapy, which included the same heparin therapy followed by warfarin on days 2 to 3 and was continued for 6 weeks only. Clinical and duplex ultrasound follow-up was done at 6 weeks, 3 and 6 months, and every 6 months thereafter. Results: Risk factors, location of DVT, and mean age of the 2 groups were comparable. Mean follow-up was 59 months. There were 4 immediate major complications in patients of group A (4 of 54 [7%]; 2 PEs and 2 significant bleeds) and 3 in patients of group B (3 of 51 [6%]; 1 PE and 2 bleeds). On long-term follow-up, 18 of 43 (42%) patients in group A and 20 of 44 (46%) patients in group B had PTS. Similarly, 10 of 43 (23%) patients in group A and 9 of 44 (20%) patients in group B had 1 or more recurrent thromboembolic events (not statistically significant). A significant difference was demonstrated only in patients with cancer; LTA was favored in reducing recurrent DVT and PTS. Two other patients in group A had late significant complications secondary to warfarin (hemorrhage in 1 and coumadin necrosis in the other), with no complications in group B. The mean number of days of hospitalization were fewer for patients in group B (5 versus 8 days), which is mainly due to earlier initiation of warfarin therapy for group B. Conclusion: In this study of our local population, we observed that short-term anticoagulation therapy was as effective as LTA therapy and less costly for use in most patients. It may also carry less risk of long-term warfarin complications, such as bleeding or skin necrosis. (J Vasc Surg 1998;28:630-7.

Quick Mobile Power Unit Trailer Connections

This Final Design Review document encompasses the entirety of a sponsored senior project which was conducted by a group of four undergraduate mechanical engineers at California Polytechnic University San Luis Obispo. The primary sponsor of this project was Solar Turbines, a subsidiary of Caterpillar Incorporated. Solar Turbines is in the business of development and application of modern-day energy solutions with a large focus on gas powered turbines. Cal Poly acted as a supplemental support of this project and provide the students with mentorship as well as access to its state-of-the-art facilities for the development of an innovative solution to the design challenge submitted by Solar Turbines. The submittal states a desire to improve the deployment timeline of Solar Turbines’ Titan 130 Gas Turbine Mobile Power Unit. This unit hosts a split drive train with a turbine mounted on one semi-trailer (driving trailer) and a generator mounted on another semi-trailer (driven trailer). These two trailers must be accurately aligned and securely fastened, currently taking roughly 12 hours. Seven of these hours account for aligning and leveling the two trailers and five hours account for securing the trailers using tension bolt fasteners. The process is desired to be reduced to 4 hours without compromising the strength of the connection points. The specified alignment tolerance of the trailers was given as + ¼ inch. The primary stresses in the connection are due to the torsional load resulting from the rotation of the turbine. There are two load conditions that were factored into the design: the normal operating load and the short circuit load. The normal operation load of #### ft-lbf is the torque to be experienced by the bolts as a result of the normal operation of the turbine. The short circuit load (#### ft-lbf) is the resulting torque the system undergoes should the generator seize. This document initially presents the background research and function identification processes followed by the ideation process used to develop various solutions to the problem. The final selection processes are also laid out in detail with the final solution chosen being a hydraulically actuated form of alignment using hydraulic arms and wedge connections between the trailers. Critical component dimensions were then confirmed using hand calculations and ANSYS to conduct FEA. Manufacturing and assembly plans including a bill of materials for a full prototype are provided. In addition, testing plans which can be applied to any scale of prototype are also provided. Due to the emergence of Covid-19 during the third phase of the project, prototype development was unable to be completed. Instead further ANSYS analysis (Rigid Body Dynamic) was done in order to further support the solution provided. The goal of this final document is to provide Solar Turbines with all material listed in the Scope of Work agreement and easily lay out prototype development and testing plans that can be used by Solar Turbines if they decide to build a prototype themselves

Interactive deep maps and spatial narratives for landscape conservation and public engagement

Landscape conservation science and practice has increasingly embraced a “people and nature” paradigm that recognizes the dynamic complexity and bidirectional relationships in social-ecological systems. Conservation research remains heavily biased toward the ecological dimensions of conservation, with socially focused research taking up a relatively small fraction. The digital revolution and accompanying geospatial web inspired platforms and methods that provide a significant opportunity for closing this divide. This article focuses on potential contributions to conservation science and practices from one such integrative platform—interactive deep maps and their resulting spatial narratives— that digitally combine the qualitative and experiential essence(s) of place with the quantitative capabilities of Cartesian space. By critically exploring emerging work, we propose that interactive deep maps and spatial narratives are uniquely positioned for integrating social and ecological dimensions of place-based conservation by linking the lived experiences of people with the spatially represented ecological characteristics of nature

Comparative analysis of classic brain component sizes in relation to flightiness in birds

Increased encephalization has been linked to a range of behavioural traits and scenarios. However, studies of whole brain size in this context have been criticised for ignoring the role of specific brain areas in controlling behaviour. In birds, the response to potential threats is one such behaviour that may relate to the way in which the brain processes sensory information. We used a phylogenetic generalised least squares (PGLS) analyses, based on five different phylogenetic hypotheses, to analyse the relationship of relative sizes of whole brain and brain components with Flight-Initiation Distance (FID), the distance at which birds flee from an approaching human, for 41 bird species. Starting distance (the distance at which an approach to a bird commences), body mass and eye size have elsewhere been shown to be positively associated with FID, and consequently were included as covariates in our analysis. Starting distance and body mass were by far the strongest predictors of FID. Of all brain components, cerebellum size had the strongest predictor weight and was negatively associated with FID but the confidence intervals on the average estimate included zero and the overall predictor weight was low. Models featuring individual brain components were generally more strongly weighted than models featuring whole brain size. The PGLS analyses estimated there to be no phylogenetic signal in the regression models, and hence produced results equivalent to ordinary least squares regression analysis. However analyses that assumed strong phylogenetic signal produced substantially different results with each phylogeny, and overall suggest a negative relationship between forebrain size and FID. Our analyses suggest that the evolutionary assumptions of the comparative analysis, and consideration of starting distance make a profound difference to the interpretation of the effect of brain components on FID in birds

Participatory mobile- and web-based tools for eliciting landscape knowledge and perspectives: introducing and evaluating the Wisconsin geotools project

Despite synergistic goals across a wide breadth of fields and modalities, coastal landscape conservation projects that engage the lay public and integrate narratives of place remain elusive. This paper addresses these needs by introducing and evaluating the Wisconsin Geotools, an integrated pair of mobile-and web-based applications that allow users to generate and share spatially defined multimedia observations — including photos, short textual descriptions (or journals), and audio and video clips — of their surrounding bioregional landscapes. We followed a participatory, user-centered design process to develop a mobile application that uses GPS capabilities to geolocate multimedia observations of landscapes and feed them into a web-based application, which displays content through the structure of an interactive story map. The applications were piloted with coastal community user groups in Green Bay (Lake Michigan), Wisconsin, USA. Over 800 observations were recorded by participants in our study area. Results from a user evaluation survey indicate the geotools effectively engaged participants in learning about and exploring their surrounding coastal landscapes. A spatial analysis revealed participants’ affinity for water-related features in landscapes. We close by suggesting a variety of ways in which these tools can support future projects and existing methodologies that are advancing transdisciplinary approaches to engaging the public in coastal conservation

Variation at the DRD4 locus is associated with wariness and local site selection in urban black swans

 BACKGROUND: Interactions between wildlife and humans are increasing. Urban animals are often less wary of humans than their non-urban counterparts, which could be explained by habituation, adaptation or local site selection. Under local site selection, individuals that are less tolerant of humans are less likely to settle in urban areas. However, there is little evidence for such temperament-based site selection, and even less is known about its underlying genetic basis. We tested whether site selection in urban and non-urban habitats by black swans (Cygnus atratus) was associated with polymorphisms in two genes linked to fear in animals, the dopamine receptor D4 (DRD4) and serotonin transporter (SERT) genes. RESULTS: Wariness in swans was highly repeatable between disturbance events (repeatability = 0.61) and non-urban swans initiated escape from humans earlier than urban swans. We found no inter-individual variation in the SERT gene, but identified five DRD4 genotypes and an association between DRD4 genotype and wariness. Individuals possessing the most common DRD4 genotype were less wary than individuals possessing rarer genotypes. As predicted by the local site selection hypothesis, genotypes associated with wary behaviour were over three times more frequent at the non-urban site. This resulted in moderate population differentiation at DRD4 (FST = 0.080), despite the sites being separated by only 30 km, a short distance for this highly-mobile species. Low population differentiation at neutrally-selected microsatellite loci and the likely occasional migration of swans between the populations reduces the likelihood of local site adaptations. CONCLUSION: Our results suggest that wariness in swans is partly genetically-determined and that wary swans settle in less-disturbed areas. More generally, our findings suggest that site-specific management strategies may be necessary that consider the temperament of local animals