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Water vapor (H2O) is the strongest greenhouse gas in our atmosphere. Hence, accurate measurements and a correct representation in global models of H2O in the upper troposphere/lower stratosphere (UTLS) are important for understanding and projecting climate. Here we compare balloon‐borne measurements of UTLS H2O, performed by cryogenic frostpoint hygrometers (CFH) and meteorological radiosondes (Vaisala RS41) during two intensive field campaigns in the Asian summer monsoon anticyclone region, with humidity data from three products of the European Centre for Medium‐range Weather Forecasts (ECMWF): operational analysis and forecast (termed OPERA), ERA‐Interim reanalysis, and the newly released ERA5 reanalysis. Taking CFH as a reference, we show that OPERA and ERA5 provide a more accurate representation of UTLS H2O than ERA‐Interim. In particular, OPERA and ERA5 similarly overestimate H2O mixing ratios by on average 0.7–0.8 ppmv (14–15%) and 0.7–0.9 ppmv (15–17%) at pressures 60–100 hPa, respectively, and both provide a good representation of the observed vertical distribution (including fine structures) and natural variability of UTLS H2O. In contrast, ERA‐Interim underestimates UTLS H2O by 0.6–1.7 ppmv (14–30%), and it fails to capture relevant features of the vertical distribution of UTLS H2O. At pressures (p) lower than 60 hPa, all three ECMWF products are in good agreement with CFH. Humidity measurements by RS41 show an average dry bias of 0.1–0.5 ppmv (3–9%) compared to CFH for 60–100 hPa, and a moist bias increasing with altitude for p < 60 hPa, exceeding 100% for p < 40 hPa. Key Points: ECMWF operational and ERA5 data show moist bias (14–17%) in UTLS water vapor compared to cryogenic frostpoint hygrometer (CFH)ERA‐Interim data shows dry bias (14–30%) in UTLS water vapor compared to CFHNew ERA5 reanalysis provides an improved representation of UTLS water vapor compared to ERA‐Interim reanalysis [ABSTRACT FROM AUTHOR]

Human dental pulp stem cells (hDPSCs) reside in postnatal dental pulp and exhibit the potential to differentiate into odontoblasts as well as neurons. However, the intercellular signaling niches necessary for hDPSC survival and self-renewal remain largely unknown. The objective of this study is to demonstrate the existence of intercellular purinergic signaling in hDPSCs and to assess the impact of purinergic signaling on hDPSC survival and proliferation. hDPSCs were isolated from extracted third molars and cultured in minimum essential medium. To demonstrate responsiveness to ATP application and inhibitions by purinergic receptor antagonists, whole cell patch-clamp recordings of ATP-induced currents were recorded from cultured hDPSCs. Immunofluorescence and enzymatic histochemistry staining were performed to assess purinergic receptor expression and ectonucleotidase activity in hDPSCs, respectively. To determine the effects of purinergic signaling on hDPSC, purinergic receptor antagonists and an ectonucleotidase inhibitor were applied in culture medium, and hDPSC survival and proliferation were assessed with DAPI staining and Ki67 immunofluorescence staining, respectively. We demonstrated that ATP application induced inward currents in hDPSCs. P2X and P2Y receptors are involved in the generation of ATP-induced inward currents. We also detected expression of NTPDase3 and ectonucleotidase activity in hDPSCs. We further demonstrated that purinergic receptors were tonically activated in hDPSCs and that inhibition of ectonucleotidase activity enhanced ATP-induced inward currents. Furthermore, we found that blocking P2Y and P2X receptors reduced-and inhibition of ecto-ATPase activity enhanced-the survival and proliferation of hDPSCs, while blocking P2X receptors alone affected only hDPSC proliferation. Autocrine/paracrine purinergic signaling is essential for hDPSC survival and proliferation. These results reveal potential targets to manipulate hDPSCs to promote tooth/dental pulp repair and regeneration. [ABSTRACT FROM AUTHOR]

Purinergic signaling is involved in pain generation and modulation in the nociceptive sensory nervous system. Adenosine triphosphate (ATP) induces pain via activation of ionotropic P2X receptors while adenosine mediates analgesia via activation of metabotropic P1 receptors. These purinergic signaling are determined by ecto-nucleotidases that control ATP degradation and adenosine generation. Using enzymatic histochemistry, we detected ecto-AMPase activity in dental pulp, trigeminal ganglia (TG) neurons, and their nerve fibers. Using immunofluorescence staining, we confirmed the expression of ecto-5'-nucleotidase (CD73) in trigeminal nociceptive neurons and their axonal fibers, including the nociceptive nerve fibers projecting into the brainstem. In addition, we detected the existence of CD73 and ecto-AMPase activity in the nociceptive lamina of the trigeminal subnucleus caudalis (TSNC) in the brainstem. Furthermore, we demonstrated that incubation with specific anti-CD73 serum significantly reduced the ecto-AMPase activity in the nociceptive lamina in the brainstem. Our results indicate that CD73 might participate in nociceptive modulation by affecting extracellular adenosine generation in the trigeminal nociceptive pathway. Disruption of TG neuronal ecto-nucleotidase expression and axonal terminal localization under certain circumstances such as chronic inflammation, oxidant stress, local constriction, and injury in trigeminal nerves may contribute to the pathogenesis of orofacial neuropathic pain. [ABSTRACT FROM AUTHOR]

The GCOS (Global Climate Observing System) Reference Upper-Air Network (GRUAN) data processing for the Vaisala RS92 radiosonde was developed to meet the criteria for reference measurements. These criteria stipulate the collection of metadata, the use of well-documented correction algorithms, and estimates of the measurement uncertainty. An important and novel aspect of the GRUAN processing is that the uncertainty estimates are vertically resolved. This paper describes the algorithms that are applied in version 2 of the GRUAN processing to correct for systematic errors in radiosonde measurements of pressure, temperature, humidity, and wind, as well as how the uncertainties related to these error sources are derived. Currently, the RS92 is launched on a regular basis at 13 out of 15 GRUAN sites. An additional GRUAN requirement for performing reference measurements with the RS92 is that the manufacturerprescribed procedure for the radiosonde's preparation, i.e. heated reconditioning of the sensors and recalibration during ground check, is followed. In the GRUAN processing however, the recalibration of the humidity sensors that is applied during ground check is removed. For the dominant error source, solar radiation, laboratory experiments were performed to investigate and model its effect on the RS92's temperature and humidity measurements. GRUAN uncertainty estimates are 0.15K for night-time temperature measurements and approximately 0.6K at 25 km during daytime. The other uncertainty estimates are up to 6% relative humidity for humidity, 10-50m for geopotential height, 0.6 hPa for pressure, 0.4-1ms–1 for wind speed, and 1° for wind direction. Daytime temperature profiles for GRUAN and Vaisala processing are comparable and consistent within the estimated uncertainty. GRUAN daytime humidity profiles are up to 15% moister than Vaisala processed profiles, of which two-thirds is due to the radiation dry bias correction and onethird is due to an additional calibration correction. Redundant measurements with frost point hygrometers (CFH and NOAA FPH) show that GRUAN-processed RS92 humidity profiles and frost point data agree within 15% in the troposphere. No systematic biases occur, apart from a 5% dry bias for GRUAN data around –40 °C at night. [ABSTRACT FROM AUTHOR]

The article focuses on an enhanced tropospheric nitrogen dioxide column retrieval algorithm for Ozone Monitoring Instrument (OMI) based on a better air mass factors (AMF). It reveals that dedicated evaluations of previous tropospheric nitrogen dioxide retrievals indicated that the tropospheric columns were susceptible to high biases. The DOMINO air mass factor method is discussed.