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Through the Wilderness: Andrew Jackson\u27s Military Road and the Settlement of the Southern Frontier
No full textShortly after the War of 1812, the U.S government attempted to construct a new military road system connecting Nashville, Tennessee to strategic ports at New Orleans and Mobile. The road was intended to grant faster military responses to British, Spanish, and Indian threats within America’s southern frontier and to aid in the region’s settlement. The American government directed iconic General Andrew Jackson to spearhead the road’s construction, believing the construction would be rapid and the expenses minimal. However, the impenetrable thickets and inundating swamps of the Mississippi Territory proved untamable, while shifting geo-political dynamics mitigated the road’s necessity. Never used for massive troop deployment and with a negligible impact on the settlement of Mississippi, the Jackson Military Road proved to be a costly, futile endeavor
Have psychologists increased reporting of outliers in response to the reproducibility crisis?
No full textPsychology is currently experiencing a “renaissance” where the replication and reproducibility of published reports are at the forefront of conversations in the field. While researchers have worked to discuss possible problems and solutions, work has yet to uncover how this new culture may have altered reporting practices in the social sciences. As outliers and other errant data points can bias both descriptive and inferential statistics, the search for these data points is essential to any analysis using these parameters. We quantified the rates of reporting of outliers and other data within psychology at two time points: 2012 when the replication crisis was born, and 2017, after the publication of reports concerning replication, questionable research practices, and transparency. A total of 2235 experiments were identified and analyzed, finding an increase in reporting from only 15.7% of experiments in 2012 to 25.0% in 2017. We investigated differences across years given the psychological field or statistical analysis that experiment employed. Further, we inspected whether data exclusions mentioned were whole participant observations or data points, and what reasons authors gave for stating the observation was deviant. We conclude that while report rates are improving overall, there is still room for improvement in the reporting practices of psychological scientists which can only aid in strengthening our science
Variation in riparian and stream assemblages across the primary succession landscape of Mount St. Helens, U.S.A.
No full textAlthough most lotic ecosystems experience frequent and sometimes large disturbances, opportunities are uncommon to study primary succession in streams. Exceptions include new stream channels arising from events such as glacial retreat, volcanism, and catastrophic landslides. In 1980, the eruption and massive landslide at Mount St. Helens (WA, U.S.A.) created an entire landscape with five new catchments undergoing primary succession. We asked if riparian and lotic assemblages at early successional stages (36 years after the eruption) showed predictable change along longitudinal gradients within catchments, and whether assemblages were similar among five replicate catchments. In July 2016, we collected environmental data and characterised riparian, algal, and benthic macroinvertebrate assemblages at 21 stream reaches distributed within and among five neighbouring catchments. We evaluated patterns of richness, abundance, biomass, multivariate taxonomic community structure, and functional traits both longitudinally and among catchments. We found minimal evidence that longitudinal gradients had developed within catchments at 36 years post-eruption. Increases in diatom and macroinvertebrate richness with downstream distance were the only biological responses with longitudinal trends. Conversely, we documented substantial variation in community structure of riparian plants, soft-bodied algae, diatoms, and macroinvertebrates at the among-catchment scale. Among-catchment differences consistently separated two eastern catchments from three western catchments, and these two groups also differed in stream water chemistry, water temperature, and geomorphology. Overall, we documented greater diversity in the young catchments than predicted by ecologists in the years immediately following the eruption, yet functional traits indicate that these catchments are still in relatively early stages of succession. Variation at the among-catchment scale is likely to be driven in part by hydrological source variation, with the two eastern catchments showing environmental signatures associated with glacial ice-melt and the three western catchments probably fed primarily by springs from groundwater aquifers. Contemporary flow disturbance regimes also varied among catchments and successional trajectories were probably reset repeatedly in streams experiencing more frequent disturbance. Similar to new stream channels formed following glacial retreat, our results support a tolerance model of succession in streams. However, contrasting abiotic templates among Mount St. Helens catchments appear to be driving different successional trajectories of riparian plant, algal, and macroinvertebrate assemblages among neighbouring small catchments sharing the same catastrophic disturbance history
Pollinators mediate floral microbial diversity and microbial network under agrochemical disturbance
No full textHow pollinators mediate microbiome assembly in the anthosphere is a major unresolved question of theoretical and applied importance in the face of anthropogenic disturbance. We addressed this question by linking visitation of diverse pollinator functional groups (bees, wasps, flies, butterflies, beetles, true bugs and other taxa) to the key properties of the floral microbiome (microbial α- and β-diversity and microbial network) under agrochemical disturbance, using a field experiment of bactericide and fungicide treatments on cultivated strawberries that differ in flower abundance. Structural equation modelling was used to link agrochemical disturbance and flower abundance to pollinator visitation to floral microbiome properties. Our results revealed that (i) pollinator visitation influenced the α- and β-diversity and network centrality of the floral microbiome, with different pollinator functional groups affecting different microbiome properties; (ii) flower abundance influenced the floral microbiome both directly by governing the source pool of microbes and indirectly by enhancing pollinator visitation; and (iii) agrochemical disturbance affected the floral microbiome primarily directly by fungicide, and less so indirectly via pollinator visitation. These findings improve the mechanistic understanding of floral microbiome assembly, and may be generalizable to many other plants that are visited by diverse insect pollinators in natural and managed ecosystems
Phase transitions in CaCO3under hydrous and anhydrous conditions: Implications for the structural transformations of CaCO3during subduction processes
No full textThe transport of calcium carbonate (CaCO3) into the Earth\u27s interior through subduction is one of the key processes in the global cycling of carbon. To develop a better understanding of the CaCO3 structural stability during subduction processes, the phase transitions among CaCO3-I (calcite), CaCO3- II, -III/IIIb, and aragonite under pressure-temperature (P-T) conditions up to 2.5 GPa and 600 °C, in hydrous and anhydrous environments, were investigated using a hydrothermal diamond-anvil cell. One displacive and two reconstructive processes during the phase transitions among CaCO3 polymorphs were confirmed from the results obtained from in situ observations and Raman spectroscopic measurements. Meanwhile, the efect of Ca-substitutional metal cations (e.g., Mg2+) in CaCO3 and the presence of an aqueous fluid on the phase transition processes have been determined. Specifically, the CaCO3-I ↔ -II phase transition is a displacive process, occurring instantly at pressures varying from 1.6 GPa at room temperature to 1.5 GPa at 500 °C with the phase equilibrium boundary having a minimum P-T point at ∼1.4 GPa at 300 °C, and is completely reversible upon cooling and decompression. The CaCO3-II → -III phase transition is a reconstructive process, observed at P-T conditions from 2.0 GPa at room temperature to 2.5 GPa at 150 °C, and is accomplished by solid recrystallization starting from CaCO3-II, transitioning through an intermediate CaCO3-IIIb, and ending at the CaCO3-III structure. The phase transition between CaCO3-I or -II and aragonite, which is also a reconstructive process, was found to occur by progressive solid recrystallization under high P-T hydrous and anhydrous conditions, or alternatively, via dissolution-precipitation under low-P-T hydrous conditions, depending on the presence of aqueous fluids and the heating rate of the system. The substitution for Ca2+ by other metal cations (e.g., Mg2+, Mn2+, Fe2+) in CaCO3 results in a significant increase in the pressures for the displacive and solid recrystallization reconstructive phase transitions, but has no detectable influence on the CaCO3-I/II ↔ aragonite transformation via a dissolution-precipitation process under hydrous conditions. Our results show that the presence of Ca-substitutional metal cations in CaCO3 is a key factor controlling the phase stability of CaCO3 under high P-T conditions, and suggest that aragonite should be the predominant phase in the upper mantle in subduction zones where the heating rate is very low and slab dehydration is prevalent
Expression and Purification of Cytochrome 2U1 and Canine 1A2 and Metabolism of Caffeine by Cytochrome 1A2
No full textCytochrome P450 enzymes are a large family of membrane heme proteins involved in eliminating drugs and the synthesis or elimination of steroids, eicosanoids, and vitamins. CYP2U1 is one of the poorly characterized P450 enzymes classified as orphan cytochrome P450 with unknown exact biological function. It is expressed in the brain and thymus as a catalyst in the hydroxylation of arachidonic acid. Unlike other cytochrome P450s, CYP2U1 is a bit unusual with forty extra amino acids. If a mutation occurs, it can lead to an early onset inherited disorder of the central nervous system called Hereditary Spastic Paraplegias (HSP). Most of the P450 enzymes in humans are known and characterized based on their structure and functions. Many of them have orthologous proteins in other species. CYP1A2 metabolizes many substrates like phenacetin, caffeine, acetaminophen, and theobromine (from chocolate) which makes it likely that there are differences between the activity of the canine and human CYP1A2 enzyme. The human CYP1A2 protein is well characterized and has a crystal structure available. This has implications in the treatment of canines in veterinary medicine and in drug metabolism studies, which are sometimes conducted in dogs. Few studies have been conducted to look at the biochemistry of the purified canine CYP1A2. Synthesis of the canine CYP1A2 gene and human CYP 2U1 followed by cloning into the pCW plasmid was done and grown in E. coli JM109 cells for the production of large amounts of proteins that were isolated by breaking the cells open through sonication, solubilized with the detergent CHAPS, and purified with Nickel affinity and ion-exchange chromatography. The purity of the protein after purification was measured by gel electrophoresis and UV-vis chromatography. The purified CYP 1A2 protein was used to characterize the metabolism of caffeine, a substance known to be metabolized by human CYP1A2
Repeatability of water loss and gain rates of Plethodon cinereus
No full textWater loss and gain rates of amphibians are important to understanding their ecology, especially for plethodontid salamanders. We report the first estimates of repeatability of relative water loss and gain rates of the two major colour morphs of the Eastern Red-backed Salamander, Plethodon cinereus, in the fall and spring seasons. Repeatability of relative water loss in P. cinereus was \u3e0 in the fall but not in the spring. Repeatability of relative water gain was significant for all salamanders pooled in the fall, and was not repeatable in the spring. There were no apparent differences in repeatability of relative water loss or gain between the two colour morphs. Our results suggest that the repeatability of relative water loss and gain rates varies by season, but not by colour morph
A Longitudinal Examination of Work–Family Balance among Working Mothers in the United States: Testing Bioecological Theory
No full textThe current study used a bioecological framework to examine three moderated-mediation models testing the mediating effects of positive work-to-family spillover and positive family-to-work spillover in the relationship between a nonstandard work schedule and work–family balance as well as between relationship quality and work-to-family balance. The moderating effects of education, family–friendly workplace policies, and race in the aforementioned models also were tested. Path analyses were used with longitudinal data from four-time periods to test the models. Results showed family-to-work spillover mediated the relationship between relationship quality and work–family balance in two models, whereas the availability of family–friendly policies significantly moderated these relationships. Relationship quality was one of the most consistently significant variables across all models, suggesting its role in helping establish work-family balance is particularly influential regardless of context. Implications and directions for future research are discussed
Development of Eam and Rf-MEAM Interatomic Potential for Zirconium Diboride
No full textEmbedded Atom Method (EAM) and Modified-EAM (MEAM) interatomic potentials were developed for zirconium diboride (ZrB2). The EAM and “Reference Free” (RF) version of the Modified Embedded Atom Method (RFMEAM) potentials have been fitted by utilizing Density Functional Theory (DFT)-based datasets including lattice deformations and high-temperature ab-initio molecular dynamics (AIMD) simulation results. The occupancies of phonons for acoustic phonon modes from the density functional theory calculation shows that these modes of vibration, mostly due to heavier mass element (Zr), which occur below 8.711 THz, while a slight underestimation to that of DFT calculation predicted by EAM below 8.439 THz and an overestimation predicted by RF-MEAM below 8.880 THz. Consequently, the frequency shifting of acoustic phonon modes for heavier mass element (Zr) on EAM and RF-MEAM potential models results in a similar frequency shifts on optical modes which is mostly due to lighter element (B); the frequency range for optical modes is 12.013-22.733 THz for EAM and 12.616-23.957 THz for RF-MEAM models compared to the frequency range of 12.181-23.124 THz by DFT calculation. In addition, the bulk modulus of ZrB2 for EAM and RF-MEAM potential models are 263.81 GPa and 254.78 GPa compared to that of ground state DFT calculation of 238 GPa. Overall, the results showed that the applicability of EAM and RF-MEAM to modeling the interatomic potentials of the diboride system
(Australian): Challenges of the Australian Flying Corps During World War I
No full textThe air forces of the Great War faced many challenges. These challenges included integrating air power into established military doctrine and coping with the ever evolving airplane technology. The hurdles identified had to be overcome in order for the belligerent nations to wage a successful aerial campaign and control the skies above both static and dynamic forces. For the members of the Australian Flying Corps, these shared challenges were augmented by being the lone British dominion to operate an independent air arm. But what were these additional challenges and how were they overcome? The goal of this thesis is to explore the unique challenges that faced the AFC, both the organization and the individual men of the corps. The majority of these challenges were the product of Australian nationalist and military goals. These dual goals centered on waging a successful military campaign while at the same time maintaining a distinct dominion identity. In achieving these goals, the dominion sought to raise its standing within the British Empire, a footing on par with that of England. While other nations with an independent air arm sought similar goals to various degrees, none were an imperial possession in the same manner as Australia. Unfortunately for the Australian military and government, these nationalist and military goals were not always compatible and often were at odds with each other. As the majority of the AFC historiography focuses on the combat experiences of the Australian airman, this paper focuses and explores the social and cultural challenges with the Great War as the context and catalyst. While it is impossible to quantify each nation’s unique obstacles, it is safe to assert that in overcoming their cultural and social challenges the AFC faced the one of more challenging paths to achieving its military and cultural goals in the First World War