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The Planetary Boundary Layer height (PBLH) is essential for studying PBL and ocean‐atmosphere interactions. Marine PBL is usually defined to include a mixed layer (ML) and a capping inversion layer. The ML height (MLH) estimated from the measurements of aerosol backscatter by a lidar was usually compared with PBLH determined from radiosondes/dropsondes in the past, as the PBLH is usually similar to MLH in nature. However, PBLH can be much greater than MLH for decoupled PBL. Here we evaluate the retrieved MLH from an airborne lidar (HSRL‐2) by utilizing 506 co‐located dropsondes during the ACTIVATE field campaign over the Northwest Atlantic from 2020 to 2022. First, we define and determine the MLH and PBLH from the temperature and humidity profiles of each dropsonde, and find that the MLH values from HSRL‐2 and dropsondes agree well with each other, with a coefficient of determination of 0.66 and median difference of 18 m. In contrast, the HSRL‐2 MLH data do not correspond to dropsonde‐derived PBLH, with a median difference of −47 m. Therefore, we modify the current operational and automated HSRL‐2 wavelet‐based algorithm for PBLH retrieval, decreasing the median difference significantly to −8 m. Further data analysis indicates that these conclusions remain the same for cases with higher or lower cloud fractions, and for decoupled PBLs. These results demonstrate the potential of using HSRL‐2 aerosol backscatter data to estimate both marine MLH and PBLH and suggest that lidar‐derived MLH should be compared with radiosonde/dropsonde‐determined MLH (not PBLH) in general. Plain Language Summary: The Planetary Boundary Layer Height (PBLH) is essential for studying the lower atmosphere and its interaction with the surface. Usually, it contains a mixed layer (ML) with vertically well‐mixed (i.e., nearly constant) specific humidity and potential temperature. Over the ocean, the PBL is usually coupled (vertically well‐mixed) and the ML height (MLH) is usually close to PBLH, hence the MLH estimated from the measurements of aerosol backscatter by a lidar is traditionally compared with PBLH determined from radiosondes/dropsondes. However, when the PBL is decoupled (not vertically well mixed), the MLH differs from the PBLH. Here we used dropsondes' thermodynamic profile to evaluate the airborne High‐Spectral‐Resolution Lidar—Generation 2 (HSRL‐2) estimation of MLH and PBLH in airborne field campaign over the northwestern Atlantic (ACTIVATE) from 2020 to 2022. We show that the HSRL‐2 has excellent MLH estimation compared to the dropsondes. We also improved the HSRL‐2 estimation of PBLH. Further data analysis indicates that these conclusions remain the same for cases with different cloud fractions, and for decoupled PBLs. These results demonstrate the potential of using HSRL‐2 aerosol backscatter data to estimate both marine MLH and PBLH and suggest that lidar‐derived MLH should be compared with radiosonde/dropsonde‐determined MLH (not PBLH) in general. Key Points: Dropsondes over the northwest Atlantic are used to determine mixed layer height (MLH) and boundary layer height (PBLH)HSRL‐2 lidar MLH product compares well with dropsonde‐derived MLH but does not correspond to PBLH for decoupled PBLThe current operational HSRL‐2 algorithm is modified to include retrieval of the PBLH for decoupled PBL [ABSTRACT FROM AUTHOR]

Background: 5-HT(2B) receptors are localized within the myenteric nervous system, but their functions on motor/sensory neurons are unclear. To explore the role of these receptors, we further characterized the 5-HT(2B) receptor antagonist RS-127445 and studied its effects on peristalsis and defecation.Experimental Approach: Although reported as a selective 5-HT(2B) receptor antagonist, any interactions of RS-127445 with 5-HT(4) receptors are unknown; this was examined using the recombinant receptor and Biomolecular Interaction Detection technology. Mouse isolated colon was mounted in tissue baths for isometric recording of neuronal contractions evoked by electrical field stimulation (EFS), or under an intraluminal pressure gradient to induce peristalsis; the effects of RS-127445 on EFS-induced and on peristaltic contractions were measured. Faecal output of rats in grid-bottom cages was measured over 3 h following i.p. RS-127445 and separately, validation of the effective doses was achieved by determining the free, unbound fraction of RS-127445 in blood and brain.Key Results: RS-127445 (up to 1 micromol x L(-1)) did not interact with the 5-HT(4) receptor. RS-127445 (0.001-1 micromol x L(-1)) did not affect EFS-induced contractions of the colon, although at 10 micromol x L(-1) the contractions were reduced (to 36 +/- 8% of control, n= 4). RS-127445 (0.1-10 micromol x L(-1)) concentration-dependently reduced peristaltic frequency (n= 4). RS-127445 (1-30 mg x kg(-1)), dose-dependently reduced faecal output, reaching significance at 10 and 30 mg x kg(-1) (n= 6-11). In blood and brain, >98% of RS-127445 was protein-bound.Conclusions and Implications: High-protein binding of RS-127445 indicates that relatively high doses are required for efficacy. The results suggest that 5-HT(2B) receptors tonically regulate colonic motility. [ABSTRACT FROM AUTHOR]

The effects of critical illness not only affect the patient and relative during the intensive care stay but often affect for a considerable time afterwards. A growing body of opinion and evidence suggests that many of the needs of those who have been critically ill can be met through critical care follow-up services. A growing number of follow-up services now exist. Their establishment, development and evaluation pose significant challenges for those involved. This paper describes Bassetlaw hospital's critical care follow-up service, how it was established and what an elementary service evaluation project has shown. The findings and experiences are compared with others in published literature, and the paper may be of interest to those who are currently involved in follow-up or who plan to develop such services in the future. [ABSTRACT FROM AUTHOR]

This electronmicroscope study of the histogenesis of mucoepidermoid carcinoma is based on 15 cases from the major and minor salivary glands. Six major cell types were identified: undifferentiated (cuboid) stem cells, intermediate (columnar) ceils, serous/mucoid secretory cells, mucus-producing goblet ceils. squamous/epidermoid cells and myoepithelium It is proposed that undifferentiated stein ceils serve as pluripotential reserves which give rise to the various cell types seen in mucoepidermoid carcinoma. Reserve cells in the acinar-intercalated duct components of the salivary glands appeared to give rise to the serous/mucoid and myoepithelial cell populations of mucoepidermoid carcinoma. Reserve cells in the proximal ducts system (intra/extralobular striated ducts and excretory ducts) differentiated into myoepithelium. intermediate (columnar) cells, squamous/epidermoid and mucus-producing goblet cell lines, It is proposed that neoplastic reserve cells give rise to different tumor types in the salivary glands. These types result from varying admixtures and arrangements of tumor cells at different stages of their structural and functional cytodifferentiation from reserve cells. It is further proposed that neoplastic reserve cells differentiate along similar cell lines as the embryonic "stem cells" in the development of normal salivary glands. [ABSTRACT FROM AUTHOR]