2,867 research outputs found

    Supramolecular study, Hirshfeld analysis and theoretical study of 6-methoxyquinoline N-oxide dihydrate

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    In the crystal structure of 6-methoxyquinoline N-oxide dihydrate, C10H9NO2 center dot 2H(2)O, (I), the presence of two-dimensional water networks is analysed. The water molecules form unusual water channels, as well as two intersecting mutually perpendicular columns. In one of these channels, the O atom of the N-oxide group acts as a bridge between the water molecules. The other channel is formed exclusively by water molecules. Confirmation of the molecular packing was performed through the analysis of Hirshfeld surfaces, and (I) is compared with other similar isoquinoline systems. Calculations of bond lengths and angles by the Hartree-Fock method or by density functional theory B3LYP, both with 6-311++G(d,p) basis sets, are reported, together with the results of additional IR, UV-Vis and theoretical studies

    Slosh Baffle Design and Test for Spherical Liquid Oxygen and Liquid Methane Propellant Tank for a Lander

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    A Vertical Test Bed (VTB) is being developed to investigate exploration technologies with earth-based landing trajectories. During this activity, a concern emerged that the VTB, with large liquid tanks, could experience unstable slosh interaction between the propellant fluid motion and the control system, leading to an investigation of slosh characteristics of the VTB. As such, slosh modeling, analysis and testing were performed, that both verified models and lead to the conclusion that baffles would be required for the full-scale vehicle. Follow-on design and testing supported development of these baffles and measurement of their performance. The majority of the tests conducted, including both subscale and full, involved the use of clear tanks containing water as a reasonable substitute for the cryogenic propellants, though a few tests involved the actual liquid oxygen and methane. Along the way, some unique test and data recording methods were employed to reduce testing complexity and cost

    Prevailing Torque Locking Feature in Threaded Fasteners Using Anaerobic Adhesive

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    This paper presents results from tests to assess the use of anaerobic adhesive for providing a prevailing torque locking feature in threaded fasteners. Test procedures are developed and tests are performed on three fastener materials, four anaerobic adhesives, and both unseated assembly conditions. Five to ten samples are tested for each combination. Tests for initial use, reuse without additional adhesive, and reuse with additional adhesive are performed for all samples. A 48-hour cure time was used for all initial use and reuse tests. Test data are presented as removal torque versus removal angle with the specification required prevailing torque range added for performance assessment. Percent specification pass rates for the all combinations of fastener material, adhesive, and assembly condition are tabulated and reveal use of anaerobic adhesive as a prevailing torque locking feature is viable. Although not every possible fastener material and anaerobic adhesive combination provides prevailing torque values within specification, any combination can be assessed using the test procedures presented. Reuse without additional anaerobic adhesive generally provides some prevailing torque, and in some cases within specification. Reuse with additional adhesive often provides comparable removal torque data as in initial use

    Profiling the plasmid conjugation potential of urinary Escherichia coli

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    Escherichia coli is often associated with urinary tract infection (UTI). Antibiotic resistance in E. coli is an ongoing challenge in managing UTI. Extrachromosomal elements – plasmids – are vectors for clinically relevant traits, such as antibiotic resistance, with conjugation being one of the main methods for horizontal propagation of plasmids in bacterial populations. Targeting of conjugation components has been proposed as a strategy to curb the spread of plasmid-borne antibiotic resistance. Understanding the types of conjugative systems present in urinary E. coli isolates is fundamental to assessing the viability of this strategy. In this study, we profile two well-studied conjugation systems (F-type and P-type) in the draft genomes of 65 urinary isolates of E. coli obtained from the bladder urine of adult women with and without UTI-like symptoms. Most of these isolates contained plasmids and we found that conjugation genes were abundant/ubiquitous, diverse and often associated with IncF plasmids. To validate conjugation of these urinary plasmids, the plasmids from two urinary isolates, UMB1223 (predicted to have F-type genes) and UMB1284 (predicted to have P-type genes), were transferred by conjugation into the K-12 E. coli strain MG1655. Overall, the findings of this study support the notion that care should be taken in targeting any individual component of a urinary E. coli isolate’s conjugation system, given the inherent mechanistic redundancy, gene diversity and different types of conjugation systems in this population

    Characterizing Plasmids in Bacteria Species Relevant to Urinary Health

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    The urinary tract has a microbial community (the urinary microbiota or urobiota) that has been associated with human health. Whole genome sequencing of bacteria is a powerful tool, allowing investigation of the genomic content of the urobiota, also called the urinary microbiome (urobiome). Bacterial plasmids are a significant component of the urobiome yet are understudied. Because plasmids can be vectors and reservoirs for clinically relevant traits, they are important for urobiota dynamics and thus may have relevance to urinary health. In this project, we sought plasmids in 11 clinically relevant urinary species: Aerococcus urinae, Corynebacterium amycolatum, Enterococcus faecalis, Escherichia coli, Gardnerella vaginalis, Klebsiella pneumoniae, Lactobacillus gasseri, Lactobacillus jensenii, Staphylococcus epidermidis, Streptococcus anginosus, and Streptococcus mitis. We found evidence of plasmids in E. faecalis, E. coli, K. pneumoniae, S. epidermidis, and S. anginosus but insufficient evidence in other species sequenced thus far. Some identified plasmidic assemblies were predicted to have putative virulence and/or antibiotic resistance genes, although the majority of their annotated coding regions were of unknown predicted function. In this study, we report on plasmids from urinary species as a first step to understanding the role of plasmids in the bacterial urobiota. IMPORTANCE The microbial community of the urinary tract (urobiota) has been associated with human health. Whole genome sequencing of bacteria permits examination of urobiota genomes, including plasmids. Because plasmids are vectors and reservoirs for clinically relevant traits, they are important for urobiota dynamics and thus may have relevance to urinary health. Currently, urobiota plasmids are understudied. Here, we sought plasmids in 11 clinically relevant urinary species. We found evidence of plasmids in E. faecalis, E. coli, K. pneumoniae, S. epidermidis, and S. anginosus but insufficient evidence in the other 6 species. We identified putative virulence and/or antibiotic resistance genes in some of the plasmidic assemblies, but most of their annotated coding regions were of unknown function. This is a first step to understanding the role of plasmids in the bacterial urobiota

    The Role of Context Reinstatement and Updating in Retrieval Practice

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    There is a considerable amount of research showing retrieval practice consistently outperforms restudying as a learning method. This superior performance, also termed the Testing Effect (TE), is posited as a result of the encoding and retrieval of contextual elements by the Episodic Context Account (ECA). The ECA relies on four assumptions to explain the beneficial effects of retrieval practice. Because part of one assumption, the ECA states the difficulty involved in mentally, or self-reinstating, the context of a target memory is related to the enhancement it receives during its retrieval. The ECA also assumes the encoding and updating of contextual elements contributes to the benefit of retrieval practice. In six experiments, (pictorial) context self-reinstatement difficulty and updating were examined to test their roles within retrieval practice. Experiment 1 – 3 opted for a single practice/study block design before a final memory test. This set of experiments showed a lack of a TE, and even its reversal, when practice conditions enabled self-reinstatement of context and updating. Experiments 4 – 6 increased the number of practice/study blocks to three to test those same factors as part of an extended learning schedule. These latter experiments did yield TEs, but practice conditions, of varying degrees of self-reinstatement and updating, did not differ from one another. In general, it was the use of context cues, either through self-reinstatement or when provided during practices, that appeared to confer benefits to retention

    AS-890-20 Resolution on Class Attendance

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    That the wording in Class Attendance policy be changed as follows: It is strongly urged that instructors accept the following “excusable” reasons for allowing students to make up missed work. And, be it further RESOLVED that the following clarifying language be added to the policy as excusable reasons for making up missed class work: B. Injury, illness, death, or any extenuating circumstances of close relatives (to include but not limited to natural, adopted, and/or in-law children, parents, legal guardian, siblings, grandparents, grandchildren as well as spouse or partner). Extenuating circumstances can be defined as serious and exceptional factors outside the student\u27s control which adversely affected the student’s attendance during class time

    Two wheeled lunar dumptruck

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    The design of a two wheel bulk material transport vehicle is described in detail. The design consists of a modified cylindrical bowl, two independently controlled direct drive motors, and two deformable wheels. The bowl has a carrying capacity of 2.8 m (100 ft) and is constructed of aluminum. The low speed, high HP motors are directly connected to the wheels, thus yielding only two moving parts. The wheels, specifically designed for lunar applications, utilize the chevron tread pattern for optimum traction. The vehicle is maneuvered by varying the relative angular velocities of the wheels. The bulk material being transported is unloaded by utilizing the motors to oscillate the bowl back and forth to a height at which dumping is achieved. The analytical models were tested using a scaled prototype of the lunar transport vehicle. The experimental data correlated well with theoretical predictions. Thus, the design established provides a feasible alternative for the handling of bulk material on the moon

    Accelerated resolution therapy: an innovative mental health intervention to treat post traumatic stress disorder

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    This document is the Accepted Manuscript version of a published work that appeared in final form in Journal of the Royal Army Medical Corps. To access the final edited and published work see http://jramc.bmj.com/content/162/2/90.full.Post-traumatic stress disorder (PTSD) is a disabling trauma and stress-related disorder that may occur after a person experiences a traumatic event, and evokes a combination of intrusion and avoidance symptoms, negative alterations in cognitions and mood, and alterations in arousal and reactivity. Accelerated resolution therapy (ART) is an emerging psychotherapy that provides fast and lasting resolution for mental health problems such as PTSD. ART has been shown to achieve a positive result in one to five sessions, typically over a 2-week period, and requires no homework, skills practice or repeated exposure to targeted events. Initial research, including one randomised control trial, has demonstrated that ART interventions can significantly reduce symptoms of psychological trauma in both civilians and US service members and veterans. These results suggest that ART be considered as either a primary treatment option or for refractory PTSD in those with a suboptimal response to endorsed first-line therapies. Conservative estimates indicate substantial potential cost savings in PTSD treatment. Despite the need for more definitive clinical trials, there is increasing interest in ART in the USA, including in the US Army. The growing positive empirical evidence is compelling, and there appears to be sufficient evidence to warrant UK researchers undertaking ART research. The armed forces offer the potential for comparative international trials. However, equally important are veterans, emergency services personnel and those subjected to violence. ART appears to also have application in other conditions, including depression, anxiety disorders, and alcohol or drug misuse. ART can potentially help personnel traumatised by the unique challenges of war and conflict zones by providing brief psychotherapy in a readily accessible and culturally competent manner. ART facilitates the provision of interventions and resolutions in theatre, thus enhancing forces’ fighting capability

    Review Article Role of toll-like receptors in multiple sclerosis

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    Abstract: Multiple Sclerosis (MS) is an autoimmune disease in which Central Nervous System (CNS) lesions result from perivascular immune cell infiltration associated with damage to myelin, oligodendrocytes and neurons. CNS autoimmunity and its regulation are dominated by the inflammatory cytokines IL17 and IFNÎł, and the opposing regulatory cytokines IL10 and the type I IFNs. Toll-like receptors (TLR) play a critical role in modulating cytokine and chemokine secretion in response to exogenous Pathogen Associated to Molecular Patterns and endogenous Danger-Associated to Molecular Patterns. Here, we systematically examine the evidence that TLR play a major role in the initiation disease, the triggering of relapses, and regulation of CNS damage. Data from human studies are supported analyses of a variety of animal models, including Experimental Autoimmune Encephalomyelitis in TLRdeficient mice
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