The fleets on the northern frontier of the Roman empire from the 1st to 3rd century

Ancient sources consistently identify a strong naval element to Roman military activity along the northern frontier from the earliest occupation campaigns to Late Antiquity. This element is formed by four established provincial fleets, the CLASSES BRITANNICA, GERMANICA, PANNONICA and MOESICA. The current understanding of these units, however, is disproportionate to their importance and some current interpretations are in urgent need of revision in view of new archaeological and epigraphic data relevant to the fleets. This study identifies and analyses the main theories and problems in the study of naval activity on the northern frontier on the basis of concrete archaeological and epigraphic evidence. In order to establish a reliable foundation for further research, every site on the northern frontier identified as a fleet base in current research is studied in detail to identify fleet related evidence. These surveys, one for each of the provincial fleets based on the northern frontier, constitute the four main chapters of the thesis. The evidence for each fleet is summarised independently at the end of each chapter to revise current understanding of the respective fleet. The concluding chapter draws on all four of these summaries and reassesses the current understanding of naval power on the northern frontier of the Roman Empire from the 1st-3rd century, highlighting several misconceptions that exist in current scholarship. As such, the study illustrates that there is substantially less evidence for the provincial fleets than is currently being assumed, while the evidence at hand is not being utilized to its full potential. It is shown that literary evidence for naval activity must be treated with far greater care than hitherto anticipated and that a number of difficulties in our understanding of Roman naval activity on the northern frontier are caused by a serious misinterpretation of the term classis. Although the “regular” fleets were evidently far smaller than currently believed and had a far more limited range of operations than assumed, the naval element in Roman military activity on the northern frontier was far more substantial than these four established classes: there is clear evidence not only for the use of ad hoc fleets, created and often requisitioned for specific military campaigns, but also that naval arms were maintained by both legions and auxiliary units. These detachments played a significant role in the control and safeguarding of the Empire’s northern frontier – probably more so than the established fleets, the CLASSES BRITANNICA, GERMANICA, PANNONICA and MOESICA

The fleets on the northern frontier of the Roman empire from the 1st to 3rd century

Ancient sources consistently identify a strong naval element to Roman military activity along the northern frontier from the earliest occupation campaigns to Late Antiquity. This element is formed by four established provincial fleets, the CLASSES BRITANNICA, GERMANICA, PANNONICA and MOESICA. The current understanding of these units, however, is disproportionate to their importance and some current interpretations are in urgent need of revision in view of new archaeological and epigraphic data relevant to the fleets. This study identifies and analyses the main theories and problems in the study of naval activity on the northern frontier on the basis of concrete archaeological and epigraphic evidence. In order to establish a reliable foundation for further research, every site on the northern frontier identified as a fleet base in current research is studied in detail to identify fleet related evidence. These surveys, one for each of the provincial fleets based on the northern frontier, constitute the four main chapters of the thesis. The evidence for each fleet is summarised independently at the end of each chapter to revise current understanding of the respective fleet. The concluding chapter draws on all four of these summaries and reassesses the current understanding of naval power on the northern frontier of the Roman Empire from the 1st-3rd century, highlighting several misconceptions that exist in current scholarship. As such, the study illustrates that there is substantially less evidence for the provincial fleets than is currently being assumed, while the evidence at hand is not being utilized to its full potential. It is shown that literary evidence for naval activity must be treated with far greater care than hitherto anticipated and that a number of difficulties in our understanding of Roman naval activity on the northern frontier are caused by a serious misinterpretation of the term classis. Although the “regular” fleets were evidently far smaller than currently believed and had a far more limited range of operations than assumed, the naval element in Roman military activity on the northern frontier was far more substantial than these four established classes: there is clear evidence not only for the use of ad hoc fleets, created and often requisitioned for specific military campaigns, but also that naval arms were maintained by both legions and auxiliary units. These detachments played a significant role in the control and safeguarding of the Empire’s northern frontier – probably more so than the established fleets, the CLASSES BRITANNICA, GERMANICA, PANNONICA and MOESICA

Do Attentional Lapses Account for the Worst Performance Rule?

The worst performance rule (WPR) describes the phenomenon that individuals’ slowest responses in a task are often more predictive of their intelligence than their fastest or average responses. To explain this phenomenon, it was previously suggested that occasional lapses of attention during task completion might be associated with particularly slow reaction times. Because less intelligent individuals should experience lapses of attention more frequently, reaction time distribution should be more heavily skewed for them than for more intelligent people. Consequently, the correlation between intelligence and reaction times should increase from the lowest to the highest quantile of the response time distribution. This attentional lapses account has some intuitive appeal, but has not yet been tested empirically. Using a hierarchical modeling approach, we investigated whether the WPR pattern would disappear when including different behavioral, self-report, and neural measurements of attentional lapses as predictors. In a sample of N = 85, we found that attentional lapses accounted for the WPR, but effect sizes of single covariates were mostly small to very small. We replicated these results in a reanalysis of a much larger previously published data set. Our findings render empirical support to the attentional lapses account of the WPR

Increased CSF aquaporin-4, and interleukin-6 levels in dogs with idiopathic communicating internal hydrocephalus and a decrease after ventriculo-peritoneal shunting

Background: Studies in animal models, in which internal hydrocephalus has been induced by obstructing the cerebrospinal fluid pathways, have documented an up-regulation of the concentrations of aquaporin-4 (AQP4) in the brain. In this study, the concentrations of aquaporin-1 (AQP1), AQP1, AQP4 and interleukin-6 (IL-6) were determined in the CSF of dogs with idiopathic communicating hydrocephalus before and after the reduction of intraventricular volume following ventriculo-peritoneal shunt (VP-shunt) treatment. Results: The concentrations of AQP4 and IL-6 were increased in the cerebrospinal fluid of dogs with hydrocephalus compared to controls. Both parameters significantly decreased after surgical treatment, accompanied by decrease of ventricular size and the clinical recovery of the dogs. AQP1 was not detectable in CSF. Conclusions: Brain AQP4 up-regulation might be a compensatory response in dogs with hydrocephalus. Future determination of AQP4 at the mRNA and protein level in brain tissue is warranted to substantiate this hypothesis

SK-channel activation alters peripheral metabolic pathways in mice, but not lipopolysaccharide-induced fever or inflammation

PURPOSE: Previously, we have shown that CyPPA (cyclohexyl-[2-(3,5-dimethyl-pyrazol-1-yl)-6-methyl-pyrimidin-4-yl]-amine), a pharmacological small-conductance calcium-activated potassium (SK)–channel positive modulator, antagonizes lipopolysaccharide (LPS)-induced cytokine expression in microglial cells. Here, we aimed to test its therapeutic potential for brain-controlled sickness symptoms, brain inflammatory response during LPS-induced systemic inflammation, and peripheral metabolic pathways in mice. METHODS: Mice were pretreated with CyPPA (15 mg/kg IP) 24 hours before and simultaneously with LPS stimulation (2.5 mg/kg IP), and the sickness response was recorded by a telemetric system for 24 hours. A second cohort of mice were euthanized 2 hours after CyPPA or solvent treatment to assess underlying CyPPA-induced mechanisms. Brain, blood, and liver samples were analyzed for inflammatory mediators or nucleotide concentrations using immunohistochemistry, real-time PCR and Western blot, or HPLC. Moreover, we investigated CyPPA-induced changes of UCP1 expression in brown adipose tissue (BAT)–explant cultures. RESULTS: CyPPA treatment did not affect LPS-induced fever, anorexia, adipsia, or expression profiles of inflammatory mediators in the hypothalamus or plasma or microglial reactivity to LPS (CD11b staining and CD68 mRNA expression). However, CyPPA alone induced a rise in core body temperature linked to heat production via altered metabolic pathways like reduced levels of adenosine, increased protein content, and increased UCP1 expression in BAT-explant cultures, but no alteration in ATP/ADP concentrations in the liver. CyPPA treatment was accompanied by altered pathways, including NFκB signaling, in the hypothalamus and cortex, while circulating cytokines remained unaltered. CONCLUSION: Overall, while CyPPA has promise as a treatment strategy, in particular according to results from in vitro experiments, we did not reveal anti-inflammatory effects during severe LPS-induced systemic inflammation. Interestingly, we found that CyPPA alters metabolic pathways inducing short hyperthermia, most likely due to increased energy turnover in the liver and heat production in BAT

Reliable brain morphometry from contrast-enhanced T1w-MRI in patients with multiple sclerosis.

Brain morphometry is usually based on non-enhanced (pre-contrast) T1-weighted MRI. However, such dedicated protocols are sometimes missing in clinical examinations. Instead, an image with a contrast agent is often available. Existing tools such as FreeSurfer yield unreliable results when applied to contrast-enhanced (CE) images. Consequently, these acquisitions are excluded from retrospective morphometry studies, which reduces the sample size. We hypothesize that deep learning (DL)-based morphometry methods can extract morphometric measures also from contrast-enhanced MRI. We have extended DL+DiReCT to cope with contrast-enhanced MRI. Training data for our DL-based model were enriched with non-enhanced and CE image pairs from the same session. The segmentations were derived with FreeSurfer from the non-enhanced image and used as ground truth for the coregistered CE image. A longitudinal dataset of patients with multiple sclerosis (MS), comprising relapsing remitting (RRMS) and primary progressive (PPMS) subgroups, was used for the evaluation. Global and regional cortical thickness derived from non-enhanced and CE images were contrasted to results from FreeSurfer. Correlation coefficients of global mean cortical thickness between non-enhanced and CE images were significantly larger with DL+DiReCT (r = 0.92) than with FreeSurfer (r = 0.75). When comparing the longitudinal atrophy rates between the two MS subgroups, the effect sizes between PPMS and RRMS were higher with DL+DiReCT both for non-enhanced (d = -0.304) and CE images (d = -0.169) than for FreeSurfer (non-enhanced d = -0.111, CE d = 0.085). In conclusion, brain morphometry can be derived reliably from contrast-enhanced MRI using DL-based morphometry tools, making additional cases available for analysis and potential future diagnostic morphometry tools