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Warm Airmass Intrusions (WAIs) from the mid‐latitudes significantly impact the Arctic water budget. Here, we combine water vapor isotope measurements from the MOSAiC expedition, with a Lagrangian‐based process attribution diagnostic to track moisture transformation in the central Arctic Ocean during two WAIs, under contrasting sea‐ice concentrations (SIC). During winter with high SIC, two moisture supplies are identified. The first is Arctic moisture, locally‐sourced over the sea ice, with isotopic composition influenced by kinetic fractionation during ice‐cloud formation and vapor deposition. This moisture is rapidly overprinted by low‐latitude moisture advected poleward during WAI. In summer under low SIC, moisture is supplied through evaporation from land and ocean, with moisture removal via liquid‐cloud and dew formation. The isotopic composition reflects the influence of higher relative humidity at the evaporation sites. Given the projected increase of frequency and duration of WAIs, our study contributes to assessing process changes in the Arctic water cycle. The movement of warm and moist airmasses from lower latitudes has a big effect on the Arctic climate system. We used data from the MOSAiC drift expedition, where we measured the isotopic composition of water vapor. Water isotopes are powerful tracers of where moisture came from and how it changed during the transport. We focused on two specific warm air intrusions, occurring in February and September 2020 respectively, when the amount of sea ice was different. During the winter, the isotopic composition of the airmasses was primarily influenced by in‐Arctic moisture exchanges over sea ice. This local moisture was swiftly replaced by isotopically‐distinct warmer and moister airmasses coming from lower latitudes during the warm intrusion. In summer, when there was less sea ice, we found that water came mainly from ocean evaporation with additional land evaporation during the air intrusion. The isotopic composition of vapor was influenced by how humid the places it came from were. As warm air intrusions are expected to happen more often and last longer in the future, our study helps us understand how they affect the Arctic water cycle. Transformation of moist airmasses and their isotopic composition during warm air intrusions depends on sea‐ice extentIn winter, warm air intrusions suppress ice‐cloud formation and kinetic isotopic fractionation over sea iceIn summer, d‐excess is driven by vapor pressure gradients between ocean skin layer and the lower atmosphere at the evaporative sites Transformation of moist airmasses and their isotopic composition during warm air intrusions depends on sea‐ice extent In winter, warm air intrusions suppress ice‐cloud formation and kinetic isotopic fractionation over sea ice In summer, d‐excess is driven by vapor pressure gradients between ocean skin layer and the lower atmosphere at the evaporative sites

The Arctic is experiencing unprecedented moistening which is expected to have far‐reaching impact on global climate and weather patterns. However, it remains unclear whether this newly sourced moisture originates locally from ice‐free ocean regions or is advected from lower latitudes. In this study, we use water vapor isotope measurements in combination with trajectory‐based diagnostics and an isotope‐enabled atmosphere general circulation model, to assess seasonal shifts in moisture sources and transport pathways in the Arctic. Continuous measurements of near‐surface vapor, δ18O, and δD were performed onboard RV Polarstern during the Multidisciplinary drifting Observatory for the Study of Arctic Climate expedition from October 2019 to September 2020. Combining this isotope data set with meteorological observations reveals that the spatiotemporal evolution of δ18O mimics changes in local temperature and humidity at synoptic to seasonal time scales, while corresponding d‐excess changes suggest a seasonal shift in the origin of moisture. Simulation results from the particle dispersion model FLEXPART support these findings, indicating that summer moisture originates from nearby open ocean, while winter moisture comes from more remote sources with longer residence time over sea‐ice. Results from a nudged ECHAM6‐wiso simulation also indicate that evaporative processes from the ocean surface reproduce summer isotope values, but are insufficient to explain measured winter isotope values. Our study provides the first isotopic characterization of Central Arctic moisture over the course of an entire year, helping to differentiate the influence of local processes versus large‐scale vapor transport on Arctic moistening. Future process‐based investigations should focus on assessing the non‐equilibrium isotopic fractionation during airmass transformation over sea‐ice. The Arctic is warming twice as fast as the world's average and its water cycle is undergoing large changes. The Arctic atmosphere is becoming more humid; however, it is unclear whether the moisture is sourced locally from ice‐free ocean regions or if the vapor is transported into the Arctic from lower latitudes. To assess the origin of the moisture, we use the isotopic composition of water vapor obtained onboard a research icebreaker drifting across the Central Arctic ocean. Our observations indicate that the spatial‐temporal evolution of δ18O follows the changes in local temperature and humidity. The corresponding deuterium excess signal, which is used as a diagnostic of moisture source conditions, suggests a seasonal shift in the origin of the air masses. Results from a backward trajectory analyses and from an atmosphere general circulation model indeed show that summer moisture originated from the ocean surface near the sampling site, while winter moisture had a longer residence time over the sea‐ice making it more prone to experience isotopic fractionation along the transport. Future model simulations should assess the importance of in‐cloud microphysics and surface moisture exchanges in winter, while additional field observations are needed to reduce the uncertainties on the isotopic data. We present a year of atmospheric water vapor isotopes measurements obtained on a drift cruise across the frozen Central Arctic oceanSummer moisture mostly originates from the open ocean and its isotopic composition reflects source region's evaporative conditionsECHAM6‐wiso cannot reproduce winter moisture's isotopic composition, suggesting non‐equilibrium exchanges during transport over sea‐ice We present a year of atmospheric water vapor isotopes measurements obtained on a drift cruise across the frozen Central Arctic ocean Summer moisture mostly originates from the open ocean and its isotopic composition reflects source region's evaporative conditions ECHAM6‐wiso cannot reproduce winter moisture's isotopic composition, suggesting non‐equilibrium exchanges during transport over sea‐ice

Paleotemperature reconstructions from ice cores are mixed signals of changes in climate and ice‐surface elevation. A common, temperature‐based paleoaltimetry method suggests these signals can be disentangled by comparing two proxy locations with similar climates. The difference between the records is assumed to be due to elevation, which is estimated by scaling the temperature difference by a lapse rate. We investigate the uncertainty associated with this approach using a case study of the Antarctic Ice Sheet during the Last Glacial Maximum. From an ensemble of climate simulations, we extract modeled temperatures at locations of real ice cores. We find uncertainty on the order of hundreds of meters that results from spatial heterogeneity in non‐adiabatic temperature change, which itself stems in part from elevation‐induced atmospheric circulation change. Our findings suggest that caution is needed when interpreting temperature‐based paleoaltimetry results for ice sheets. Ice cores, cylinders of ice extracted from glaciers or ice sheets, such as the Antarctic Ice Sheet, are important tools for studying Earth's past climate. The temperature information preserved in ice cores is a result of both changes in the climate and changes in the ice sheet. In general, the taller the ice sheet, the colder its surface. By knowing how much of the temperature information in ice cores is a result of climate and how much is a result of elevation, we can better understand how ice sheets shrank and grew as climate changed in the past. Previous efforts to answer this question have relied on a simple relationship between elevation and air temperature: with few exceptions, air in the troposphere (the lowest part of the atmosphere) gets predictably colder as it moves up in the atmosphere and warmer as it moves down. Using a computer to approximate the climate over the Antarctic Ice Sheet, we find that this elevation‐temperature relationship explains part of the temperature information stored in ice cores. We also find that the climate factors cannot be ignored as we seek to advance our understanding of how ice sheets evolved as climate changed in the past. A widely‐used, temperature‐based paleoaltimetry method is derived from the first law of thermodynamicsEstimates of relative elevation change between Antarctic ice core sites yield large uncertainties and low signal‐to‐noise ratiosUncertainty arises from spatial variability in the diabatic temperature change, which is influenced by elevation‐induced circulation changes A widely‐used, temperature‐based paleoaltimetry method is derived from the first law of thermodynamics Estimates of relative elevation change between Antarctic ice core sites yield large uncertainties and low signal‐to‐noise ratios Uncertainty arises from spatial variability in the diabatic temperature change, which is influenced by elevation‐induced circulation changes

Autonomic dysregulation is frequent in acute ischemic stroke. Several studies concluded that imbalance between sympathetic and parasympathetic cardiovascular function predisposes to malignant cardiac arrhythmia. However, there are few data on cardiovascular autonomic function in post–acute stroke patients.

It is proved that classical BRS‐invariance of the Lagrangian implies perturbative gauge invariance for tree diagrams to all orders. The proof applies in particular to the Einstein Hilbert Lagrangian of gravity.

It is proved that classical BRS-invariance of the Lagrangian implies perturbative gauge invariance for tree diagrams to all orders. The proof applies in particular to the Einstein Hilbert Lagrangian of gravity.

Zusammenfassung Funktionsstörungen des autonomen Nervensystems finden sich bei zahlreichen neurologischen und internistischen Erkrankungen. Die quantitative Diagnostik autonomer Störungen beruht zumeist auf Testverfahren zur Überprüfung kardiovaskulärer und sudomotorischer Funktion. In dieser Übersichtsarbeit werden einerseits kardiovaskuläre und sudomotorische Untersuchungsmethoden, die für den klinischen Alltag geeignet sind, und andererseits Verfahren, die eher bei wissenschaftlichen Fragestellungen Anwendung finden, beschrieben.

Peripheral neuropathy in Fabry disease predominantly involves small nerve fibers. Recently, enzyme replacement therapy (ERT) with recombinant human -galactosidase A has become available.

In the perturbative AdS–CFT correspondence, the dual field whose source are the prescribed boundary values of a bulk field in the functional integral, and the boundary limit of the quantized bulk field are the same thing. This statement is due to the fact that Witten graphs are boundary limits of the corresponding Feynman graphs for the bulk fields, and hence the dual conformal correlation functions are limits of bulk correlation functions. This manifestation of duality is analyzed in terms of the underlying functional integrals of different structure.

In temporal lobe epilepsy (TLE), there is evidence of ictal and interictal autonomic dysregulation, predominantly with sympathetic overactivity. The effects of TLE surgery on autonomic cardiovascular control and on baroreflex sensitivity (BRS) have not been studied. To evaluate such effects, we monitored heart rate (HR), systolic blood pressure (BP(sys)) and respiration in 18 TLE patients 3-4 months before and after TLE surgery. We used Blackman-Tukey spectral analysis to assess sympathetic and parasympathetic modulation as powers of HR and BP(sys) oscillations in the low frequency (LF, 0.04-0.15 Hz) and high frequency (HF, 0.15-0.5 Hz) bands. BRS was determined as the LF transfer function gain between BP and HR. After surgery, HR, BP(sys), respiration and HF powers remained unchanged, while LF powers of HR (1.57 +/- 1.54 bpm(2)) and BP(sys) (2.19 +/- 1.34 mmHg(2)) and BRS (0.68 +/- 0.31 bpm/mmHg) were smaller than pre-surgical LF powers of HR (3.87 +/- 3.26 bpm(2)) and BP(sys) (4.80 +/- 3.84 mmHg(2)) and BRS (1.12 +/- 0.39 bpm/mmHg; P < 0.05). After TLE surgery, there is a reduction of sympathetic cardiovascular modulation and BRS that might result from decreased influences of interictal epileptogenic discharges on brain areas involved in cardiovascular autonomic control. TLE surgery seems to stabilize the cardiovascular control in epilepsy patients by reducing the risk of sympathetically mediated tachyarrhythmias and excessive bradycardiac counter-regulation, both of which might be relevant for the pathophysiology of sudden unexpected death in epilepsy patients (SUDEP). Thus, TLE surgery might contribute to reducing the risk of SUDEP.

In temporal lobe epilepsy (TLE), there is evidence of ictal and interictal autonomic dysregulation, predominantly with sympathetic overactivity. The effects of TLE surgery on autonomic cardiovascular control and on baroreflex sensitivity (BRS) have not been studied. To evaluate such effects, we monitored heart rate (HR), systolic blood pressure (BPsys) and respiration in 18 TLE patients 3–4 months before and after TLE surgery. We used Blackman‐Tukey spectral analysis to assess sympathetic and parasympathetic modulation as powers of HR and BPsys oscillations in the low frequency (LF, 0.04–0.15 Hz) and high frequency (HF, 0.15–0.5 Hz) bands. BRS was determined as the LF transfer function gain between BP and HR. After surgery, HR, BPsys, respiration and HF powers remained unchanged, while LF powers of HR (1.57 ± 1.54 bpm2) and BPsys (2.19 ± 1.34 mmHg2) and BRS (0.68 ± 0.31 bpm/mmHg) were smaller than pre‐surgical LF powers of HR (3.87 ± 3.26 bpm2) and BPsys (4.80 ± 3.84 mmHg2) and BRS (1.12 ± 0.39 bpm/mmHg; P < 0.05). After TLE surgery, there is a reduction of sympathetic cardiovascular modulation and BRS that might result from decreased influences of interictal epileptogenic discharges on brain areas involved in cardiovascular autonomic control. TLE surgery seems to stabilize the cardiovascular control in epilepsy patients by reducing the risk of sympathetically mediated tachyarrhythmias and excessive bradycardiac counter‐regulation, both of which might be relevant for the pathophysiology of sudden unexpected death in epilepsy patients (SUDEP). Thus, TLE surgery might contribute to reducing the risk of SUDEP.

Abstract:: The perturbative treatment of quantum field theory is formulated within the framework of algebraic quantum field theory. We show that the algebra of interacting fields is additive, i.e. fully determined by its subalgebras associated to arbitrary small subregions of Minkowski space. We also give an algebraic formulation of the loop expansion by introducing a projective system ?( n ) of observables “up to n loops”, where ?(0) is the Poisson algebra of the classical field theory. Finally we give a local algebraic formulation for two cases of the quantum action principle and compare it with the usual formulation in terms of Green's functions.

Abstract:: Interacting fields can be constructed as formal power series in the framework of causal perturbation theory. The local field algebra is obtained without performing the adiabatic limit; the (usually bad) infrared behavior plays no role. To construct the observables in gauge theories we use the Kugo–Ojima formalism; we define the BRST-transformation as a graded derivation on the algebra of interacting fields and use the implementation of by the Kugo–Ojima operator Q int. Since our treatment is local, the operator Q int differs from the corresponding operator Q of the free theory. We prove that the Hilbert space structure present in the free case is stable under perturbations. All assumptions are shown to be satisfied in QED.