Economic interpretation of history

Citation: Sweet, Fayette Charles. The internal anatomy of the Perlidae. Senior thesis, Kansas State Agricultural College, 1900.Morse Department of Special CollectionsIntroduction: The careful student of history cannot fail to notice the tendency, quite common among historians, to overestimate the influence of great men in shaping the destinies of nations. They make the story of national life to appear as a composite biography of those who played leading roles in the drama of politics or the tragedy of war. Individuals are made masters of human destiny instead of creatures of opportunity. While the "Great men" theory, and the theory of "Moral forces" in historic interpretation are by no means to be undervalued, the contention is here made, that their importance, as historic factors, has been greatly exaggerated. A casual reader of history will find nothing whatever, in much of it, to give any clue to the reasons or causes of the changes which are chronicled. The historian who narrates the deeds of an Alexander or a Napoleon, is prone to forget the people and conditions which made their careers possible. We rarely read of the years of suffering and misery which these people underwent as a result of their country's having been drained of its resources. History tells of the fall of Napoleon, but it tells only, that his army was defeated, while he, himself, was captured and imprisoned. It does not mention the exhaustion of resources which the country suffered at the time and which made it impossible to raise men and supplies. Nor does it tell of the economic principles which he antagonized when he issued the famous Berlin and Milan decrees, that were so instrumental in alienating the people and capital of the nation from his support. This constitutes the real fall of Napoleon. Before entering into the discussion of this subject, it may be well to

Import of cytochrome c heme lyase into mitochondria

Cytochrome c heme lyase (CCHL) catalyses the covalent attachment of the heme group to apocytochrome c during its import into mitochondria. The enzyme is membrane-associated and is located within the intermembrane space. The precursor of CCHL synthesized in vitro was efficiently translocated into isolated mitochondria from Neurospora crassa. The imported CCHL, like the native protein, was correctly localized to the intermembrane space, where it was membrane-bound. As with the majority of mitochondrial precursor proteins, CCHL uses the MOM19-GIP receptor complex in the outer membrane for import. In contrast to proteins taking the general import route, CCHL was imported independently of both ATP-hydrolysis and an electrochemical potential as external energy sources. CCHL which lacks a cleavable signal sequence apparently does not traverse the inner membrane to reach the intermembrane space; rather, it translocates through the outer membrane only. Thus, CCHL represents an example of a novel, 'non-conservative' import pathway into the intermembrane space, thereby also showing that the import apparatus in the outer membrane acts separately from the import machinery in the inner membrane

A crucial role of the mitochondrial protein import receptor MOM19 for the biogenesis of mitochondria

The novel genetic method of "sheltered RIP" (repeat induced point mutation) was used to generate a Neurospora crassa mutant in which MOM19, a component of the protein import machinery of the mitochondrial outer membrane, can be depleted. Deficiency in MOM19 resulted in a severe growth defect, but the cells remained viable. The number of mitochondrial profiles was not grossly changed, but mutant mitochondria were highly deficient in cristae membranes, cytochromes, and protein synthesis activity. Protein import into isolated mutant mitochondria was decreased by factors of 6 to 30 for most proteins from all suborganellar compartments. Proteins like the ADP/ATP carrier, MOM19, and cytochrome c, whose import into wild-type mitochondria occurs independently of MOM19 became imported normally showing that the reduced import activities are solely caused by a lack of MOM19. Depletion of MOM19 reveals a close functional relationship between MOM19 and MOM22, since loss of MOM19 led to decreased levels of MOM22 and reduced protein import through MOM22. Furthermore, MOM72 does not function as a general backup receptor for MOM19 suggesting that these two proteins have distinct precursor specificities. These findings demonstrate that the import receptor MOM19 fulfills an important role in the biogenesis of mitochondria and that it is essential for the formation of mitochondria competent in respiration and phosphorylation

Genetic associations with learning over 100 days of practice

Cognitive performance is both heritable and sensitive to environmental inputs and sustained practice over time. However, it is currently unclear how genetic effects on cognitive performance change over the course of learning. We examine how polygenic scores (PGS) created from genome-wide association studies of educational attainment and cognitive performance are related to improvements in performance across nine cognitive tests (measuring perceptual speed, working memory, and episodic memory) administered to 131 adults (N = 51, ages = 20–31, and N = 80, ages = 65–80 years) repeatedly across 100 days. We observe that PGS associations with performance on a given task can change over the course of learning, with the specific pattern of change in associations differing across tasks. PGS correlations with pre-test to post-test scores may mask variability in how soon learning occurs over the course of practice. The associations between PGS and learning do not appear to simply reconstitute patterns of association between baseline performance and subsequent learning. Associations involving PGSs, however, were small with large confidence intervals. Intensive longitudinal research such as that described here may be of substantial value for clarifying the genetics of learning when implemented as far larger scale

Confined Mobility of TonB and FepA in Escherichia coli Membranes

The important process of nutrient uptake in Escherichia coli, in many cases, involves transit of the nutrient through a class of beta-barrel proteins in the outer membrane known as TonB-dependent transporters (TBDTs) and requires interaction with the inner membrane protein TonB. Here we have imaged the mobility of the ferric enterobactin transporter FepA and TonB by tracking them in the membranes of live E. coli with single-molecule resolution at time-scales ranging from milliseconds to seconds. We employed simple simulations to model/analyze the lateral diffusion in the membranes of E.coli, to take into account both the highly curved geometry of the cell and artifactual effects expected due to finite exposure time imaging. We find that both molecules perform confined lateral diffusion in their respective membranes in the absence of ligand with FepA confined to a region 0.180−0.007+0.006 μm in radius in the outer membrane and TonB confined to a region 0.266−0.009+0.007 μm in radius in the inner membrane. The diffusion coefficient of these molecules on millisecond time-scales was estimated to be 21−5+9 μm2/s and 5.4−0.8+1.5 μm2/s for FepA and TonB, respectively, implying that each molecule is free to diffuse within its domain. Disruption of the inner membrane potential, deletion of ExbB/D from the inner membrane, presence of ligand or antibody to FepA and disruption of the MreB cytoskeleton was all found to further restrict the mobility of both molecules. Results are analyzed in terms of changes in confinement size and interactions between the two proteins.Yeshttp://www.plosone.org/static/editorial#pee

Scarring Effects on Tunneling in Chaotic Double-Well Potentials

The connection between scarring and tunneling in chaotic double-well potentials is studied in detail through the distribution of level splittings. The mean level splitting is found to have oscillations as a function of energy, as expected if scarring plays a role in determining the size of the splittings, and the spacing between peaks is observed to be periodic of period {$2\pi\hbar$} in action. Moreover, the size of the oscillations is directly correlated with the strength of scarring. These results are interpreted within the theoretical framework of Creagh and Whelan. The semiclassical limit and finite-{$\hbar$} effects are discussed, and connections are made with reaction rates and resonance widths in metastable wells.Comment: 22 pages, including 11 figure

Can vitamin D status influence the effect of stress on planning and problem-solving? A randomized control trial

Background: Nutritional interventions may serve as a stress resilience strategy with important implications for human health.Objective: The aim of this study was to investigate the effect of vitamin D supplementation throughout wintertime on problem-solving and planning abilities during stressful circumstances.Design: A total of 77 male inpatients with a mean age of 48 years (range 31–81) and stress-related mental health disorders were randomly assigned into a Vitamin D supplement group (daily intake of 40 μg) or a pla-cebo supplement group (Control) (daily intake of 120 mg olive oil). The intervention period was from January 2018 to May 2018. The means and standard deviations for vitamin D status (25-hydroxyvitamin D3, nmol/L), pre- and post-test, respectively, were 58(21) and 46(15) for the Control group, and 63(18) and 76(21) for the Vitamin D group. Problem-solving and planning abilities were measured by the Tower of London (ToL) task pre- (midwinter) and post- (spring) supplement intervention. The ToL task was performed during exposure to distracting noise.Results: The results revealed that vitamin D supplementation throughout the winter had a significant effect on number of correct responses on easier (1 and 2 move) ToL problems during stress; the Vitamin D group improved significantly from pre- to post-test, whereas the Control group did not. In addition, the Vitamin D group had significantly more correct responses than the Control group on post-test. The improved perfor-mance was not related to a speed-accuracy trade off effect; both groups showed significantly decreased plan-ning times from pre- to post-test. The intervention did not differentially affect task performance on the more difficult (3 to 5 move) ToL problems. For the more demanding problems, IQ seemed to explain most of the variance regarding accuracy. Age explained most of the variance associated with task planning time.Conclusion: Vitamin D supplementation seemed to improve resilience to stress, but it was limited to performance of easier tasks.publishedVersio

Anthropometric Factors and Cutaneous Melanoma: Prospective Data from the Population-based Janus Cohort

The aim of the present study was to prospectively examine risk of cutaneous melanoma (CM) according to measured anthropometric factors, adjusted for exposure to ultraviolet radiation (UVR), in a large population-based cohort in Norway. The Janus Cohort, including 292,851 Norwegians recruited 1972–2003, was linked to the Cancer Registry of Norway and followed for CM through 2014. Cox regression was used to estimate hazard ratios (HRs) of CM with 95% confidence intervals (CIs). Restricted cubic splines were incorporated into the Cox models to assess possible non-linear relationships. All analyses were adjusted for attained age, indicators of UVR exposure, education, and smoking status. During a mean follow-up of 27 years, 3,000 incident CM cases were identified. In men, CM risk was positively associated with body mass index, body surface area (BSA), height and weight (all ptrends \u3c 0.001), and the exposure-response curves indicated an exponential increase in risk for all anthropometric factors. Weight loss of more than 2 kg in men was associated with a 53% lower risk (HR 0.47, 95% CI: 0.39, 0.57). In women, CM risk increased with increasing BSA (ptrend50.002) and height (ptrend \u3c 0.001). The shape of the height- CM risk curve indicated an exponential increase. Our study suggests that large body size, in general, is a CM risk factor in men, and is the first to report that weight loss may reduce the risk of CM among men