A History of New Orleans at Year 300

Jason Berry in conversation with Curtis Wilki

Shell Shape and Meat Condition in Selectively Bred Sydney Rock Oysters, Saccostrea glomerata (Gould, 1850): The Influence of Grow‐out Methods

The Australian edible oyster industry has been severely impacted by disease and declining yields since the 1970s. Selective breeding of Saccostrea glomerata is one measure addressing these problems by producing fast‐growing, disease‐resistant oysters. Farmers report that selected oysters have different growth characteristics than their wild counterparts using conventional grow‐out methods. This study investigated how different grow‐out methods influence commercially valuable oyster characteristics including shell length, shape, surface growth deformities and meat condition. In June 2015, selectively bred S. glomerata spat were deployed in two estuaries (Hawkesbury River and Georges River) in NSW, Australia, using three grow‐out methods (fixed trays, Stanway cylinders and floating baskets). In November 2015, oysters were transferred among grow‐out methods to test for the effects of changing grow‐out methods on oyster growth patterns. Oysters transferred from baskets to cylinders and from trays to cylinders had, on average, deeper and wider shells, a higher meat condition and fewer shell surface deformities than oysters in other grow‐out method combinations. However, these oysters were smaller than oysters not grown in cylinders. While there were some differences in growth patterns between the estuaries, overall it was the grow‐out methods that most influenced oyster characteristics. This was attributed to differences in the amount and magnitude of movement oysters experienced in the grow‐out methods, as recorded by motion sensors. This study demonstrates how grow‐out methods can be managed to achieve desired growth trajectories and therefore improve marketability among selective bred S. glomerata

The agreement between a portable contact-mat and force-plates during bilateral vertical jumps

Force plates are commonly used when assessing vertical jumping performance but are not always affordable or practical tools for all testing situations. Twenty-four participants volunteered to take part in a study investigating the agreement between bilateral force plates and a new commercially available contact mat that records jump height, flight-time (FT), and FT of individual limbs during both countermovement (CMJ) and squat (SJ) jumps. Each participant performed six jumps of each type while standing on a contact mat placed upon a pair of in-ground force plates. When compared to the force plate via ordinary least products regression, the contact mat agreed with force plate CMJ and SJ jump height, individual limb FT during CMJs, and left-leg FT during SJs. The bilateral contact mat provided valid assessment of individual limb FT during CMJs, but not SJs. Practitioners can therefore use a bilateral contact mat interchangeably with bilateral force plates to measure SJ and CMJ performance

Fis Is Essential for Capsule Production in Pasteurella multocida and Regulates Expression of Other Important Virulence Factors

P. multocida is the causative agent of a wide range of diseases of animals, including fowl cholera in poultry and wild birds. Fowl cholera isolates of P. multocida generally express a capsular polysaccharide composed of hyaluronic acid. There have been reports of spontaneous capsule loss in P. multocida, but the mechanism by which this occurs has not been determined. In this study, we identified three independent strains that had spontaneously lost the ability to produce capsular polysaccharide. Quantitative RT-PCR showed that these strains had significantly reduced transcription of the capsule biosynthetic genes, but DNA sequence analysis identified no mutations within the capsule biosynthetic locus. However, whole-genome sequencing of paired capsulated and acapsular strains identified a single point mutation within the fis gene in the acapsular strain. Sequencing of fis from two independently derived spontaneous acapsular strains showed that each contained a mutation within fis. Complementation of these strains with an intact copy of fis, predicted to encode a transcriptional regulator, returned capsule expression to all strains. Therefore, expression of a functional Fis protein is essential for capsule expression in P. multocida. DNA microarray analysis of one of the spontaneous fis mutants identified approximately 30 genes as down-regulated in the mutant, including pfhB_2, which encodes a filamentous hemagglutinin, a known P. multocida virulence factor, and plpE, which encodes the cross protective surface antigen PlpE. Therefore these experiments define for the first time a mechanism for spontaneous capsule loss in P. multocida and identify Fis as a critical regulator of capsule expression. Furthermore, Fis is involved in the regulation of a range of other P. multocida genes including important virulence factors

The Agreement Between a Portable Contact-Mat and Force-Plates During Bilateral Vertical Jumps

International Journal of Exercise Science 15(1): 632-644, 2022. Force plates are commonly used when assessing vertical jumping performance but are not always affordable or practical tools for all testing situations. Twenty-four participants volunteered to take part in a study investigating the agreement between bilateral force plates and a new commercially available contact mat that records jump height, flight-time (FT), and FT of individual limbs during both countermovement (CMJ) and squat (SJ) jumps. Each participant performed six jumps of each type while standing on a contact mat placed upon a pair of in-ground force plates. When compared to the force plate via ordinary least products regression, the contact mat agreed with force plate CMJ and SJ jump height, individual limb FT during CMJs, and left-leg FT during SJs. The bilateral contact mat provided valid assessment of individual limb FT during CMJs, but not SJs. Practitioners can therefore use a bilateral contact mat interchangeably with bilateral force plates to measure SJ and CMJ performance

MSU Xtreme: Minnesota State University, Mankato\u27s Entry into the Clean Snowmobile Challenge 2001

Minnesota State University, Mankato’s Automotive Engineering Technology program formed a team to enter the Clean Snowmobile Challenge 2001. Selections for the organization’s machine included a 2001 Polaris Edge Chassis specially outfitted with a 2000 500 cc two-stroke Polaris engine. Modifications to the snowmobile were made specifically for Clean Snowmobile Challenge 2001 events. Acceleration, emissions, cold start, noise, fuel economy/range, handling/drivability, hill climb, and static display made up the list of events featured in the competition. MSU Xtreme has modified the snowmobile in every area with special emphasis on emissions and handling. Testing and analysis of the sled’s systems brought the team to its resulting design. The technical paper describes the results of those tests, explains the team design procedures, and presents all modifications made to the snowmobile

The Agreement Between a Portable Contact-Mat and Force-Plates During Bilateral Vertical Jumps

Force plates are commonly used when assessing vertical jumping performance but are not always affordable or practical tools for all testing situations. Twenty-four participants volunteered to take part in a study investigating the agreement between bilateral force plates and a new commercially available contact mat that records jump height, flight-time (FT), and FT of individual limbs during both countermovement (CMJ) and squat (SJ) jumps. Each participant performed six jumps of each type while standing on a contact mat placed upon a pair of in-ground force plates. When compared to the force plate via ordinary least products regression, the contact mat agreed with force plate CMJ and SJ jump height, individual limb FT during CMJs, and left-leg FT during SJs. The bilateral contact mat provided valid assessment of individual limb FT during CMJs, but not SJs. Practitioners can therefore use a bilateral contact mat interchangeably with bilateral force plates to measure SJ and CMJ performance

Neutrophils Are Resistant to Yersinia YopJ/P-Induced Apoptosis and Are Protected from ROS-Mediated Cell Death by the Type III Secretion System

The human innate immune system relies on the coordinated activity of macrophages and polymorphonuclear leukocytes (neutrophils or PMNs) for defense against bacterial pathogens. Yersinia spp. subvert the innate immune response to cause disease in humans. In particular, the Yersinia outer protein YopJ (Y. pestis and Y. pseudotuberculosis) and YopP (Y. enterocolitica) rapidly induce apoptosis in murine macrophages and dendritic cells. However, the effects of Yersinia Yop J/P on neutrophil fate are not clearly defined.In this study, we utilized wild-type and mutant strains of Yersinia to test the contribution of YopJ and YopP on induction of apoptosis in human monocyte-derived macrophages (HMDM) and neutrophils. Whereas YopJ and YopP similarly induced apoptosis in HMDMs, interaction of human neutrophils with virulence plasmid-containing Yersinia did not result in PMN caspase activation, release of LDH, or loss of membrane integrity greater than PMN controls. In contrast, interaction of human PMNs with the virulence plasmid-deficient Y. pestis strain KIM6 resulted in increased surface exposure of phosphatidylserine (PS) and cell death. PMN reactive oxygen species (ROS) production was inhibited in a virulence plasmid-dependent but YopJ/YopP-independent manner. Following phagocytic interaction with Y. pestis strain KIM6, inhibition of PMN ROS production with diphenyleneiodonium chloride resulted in a reduction of PMN cell death similar to that induced by the virulence plasmid-containing strain Y. pestis KIM5.Our findings showed that Yersinia YopJ and/or YopP did not induce pronounced apoptosis in human neutrophils. Furthermore, robust PMN ROS production in response to virulence plasmid-deficient Yersinia was associated with increased PMN cell death, suggesting that Yersinia inhibition of PMN ROS production plays a role in evasion of the human innate immune response in part by limiting PMN apoptosis

Abstracts from the NIHR INVOLVE Conference 2017

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