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A profound knowledge of pollutant emissions and transport processes is essential to better assess the impact on local air quality, which ultimately affects human health. This is of special importance in the proximity of airports, as flight activities are a major source of ultrafine aerosol particles (UFP) that are associated with adverse health effects. A quantification of the aerosol population in the horizontal and in particular in the vertical distribution has not been sufficiently characterized so far, but is of crucial relevance, as the atmospheric boundary layer (ABL) is strongly interacting with aerosols. For this purpose, the fixed-wing research drone called ALADINA (Application of Light-weight Aircraft for Detecting in-situ Aerosol) was operated at a distance of approximately 4 km downwind of the German airport Berlin Brandenburg (BER) on October 11–19, 2021. During the investigation period, 140 vertical profiles of different meteorological parameters and aerosol particle sizes were obtained on six measurement days between the surface and up to a maximum altitude of 750 m above ground level (a.g.l.). The investigations indicate several features: The stability of the ABL is a key characteristic for the vertical distribution of aerosol population with highest concentrations close to ground. Inversion layers further enhance horizontal transport so that airport pollutants can be moved to a further distance away. The airborne observations of total particle number concentration (TNC) coincide with ground-based data from fix-point sites. They show a high variability depending on the distance to the plume as well as upwind position and highest concentrations of TNC related to rush hours of airport operations.

The vertical structure of temperature in the troposphere is closely related to PM 2.5 concentration in polluted regions, with temperature inversions associated to higher PM 2.5 at the surface. This fact is more relevant in places surrounded by mountains, like Santiago de Chile, where high pollution events are common in winter. A characterization of the vertical profile of PM 2.5 and temperature has been carried out in winter and spring with an unmanned aerial vehicle. Temperature inversions up to 400 m were found only in winter, with full inversions associated to the highest PM 2.5 at the surface. Days with full inversion are also characterized by very low wind speeds. In most cases, PM 2.5 decreased rapidly with altitude, even when there was mixing layer of considerable height. Consequently, PM 2.5 above 300 m was always low, in contrast to other studies, indicating that there are factors that influence the vertical concentration of PM 2.5 which are still not well understood. Chemistry transport model (CTM) simulated vertical profiles of PM 2.5 agrees qualitatively well with observed concentration profiles in spring, but there is a negative bias in comparison to the measured data and also a stronger simulated vertical gradient than observed. In winter, average simulated PM 2.5 concentrations at the surface are similar to observed, but with increasing altitude the simulated data decline faster than measured. • Vertical profile of temperature and PM 2.5 were measured in winter and spring. • Temperature inversions were found only in winter. • On days with full inversion PM 2.5 was higher and wind speed was lower than days with no inversion. • Simulated data agrees well but decline faster than measured data with altitude. • There is no spatial uniformity in PM 2.5 or temperature at 272 m. [ABSTRACT FROM AUTHOR]

Background: One of the most frequent concerns encountered in dental implant treatments is inadequate pre-operative planning. Panoramic radiographs are readily accessible and cost efficient. The aim of this study is to assess the accuracy of vertical measurements in mandibular molar and premolar region on panoramic radiography. Materials and Methods : Panoramic radiographs were made of a partially edentulous sheep mandible mounted in acryl. Measurements collected from the computer-generated images were compared to measurements made directly on the cross-sectioned hemi-mandibles using t-test. P < 0.05 was considered significant. Results: The results show that panoramic image is overestimated in predicting the linear measurements in posterior mandible. By applying the magnification factor of 1.29 the difference became insignificant. Conclusion: It seems rational to use panoramic radiography for pre-surgical implant assessment of posterior mandible if a true magnification factor is applied.

Background: One of the most frequent concerns encountered in dental implant treatments is inadequate pre-operative planning. Panoramic radiographs are readily accessible and cost efficient. The aim of this study is to assess the accuracy of vertical measurements in mandibular molar and premolar region on panoramic radiography. Materials and Methods: Panoramic radiographs were made of a partially edentulous sheep mandible mounted in acryl. Measurements collected from the computer-generated images were compared to measurements made directly on the cross-sectioned hemi-mandibles using t-test. P < 0.05 was considered significant. Results: The results show that panoramic image is overestimated in predicting the linear measurements in posterior mandible. By applying the magnification factor of 1.29 the difference became insignificant. Conclusion: It seems rational to use panoramic radiography for pre-surgical implant assessment of posterior mandible if a true magnification factor is applied. [ABSTRACT FROM AUTHOR]

ABSTRACT The residual alveolar ridge resorption is inevitable with aging. The purpose of the study was to determine and compare differences in the vertical measurements of jaw bones in elderly dentate and edentulous subjects. The study sample included 51 elderly dentate subjects and 59 edentulous subjects. The panoramic radiographs were used to quantify the reduction in the alveolar ridges at 5 sites in each jaw. There were significant differences between elderly dentate and edentulous subjects in maxilla and mandible. The percentage reduction in the vertical height of edentulous subjects as compared to dentate subjects ranges from 29% to 39%. The reduction in the heights was greater in mandible than in maxilla in both the study groups. The vertical measurements were significantly greater in men than in women in maxilla and the mandible. Vertical heights of maxillary and mandibular jaw bones are important factors in planning complete denture and the implant supported prosthesis. Further studies would be necessary to determine the region specific resorption of jaw bones and its association with the duration of denture wear in edentulous subjects. [ABSTRACT FROM AUTHOR]

Air quality in Beijing has been improved significantly in recent years; however, our knowledge of the vertically resolved aerosol chemistry in summer remains poor. Here, we carried out comprehensive measurements of aerosol composition, gaseous species, and aerosol optical properties on a meteorological tower in Beijing in summer and compared with those measured in winter. Our results showed that aerosol liquid water (ALW) contributing approximately 50% of the total mass with higher values aloft played a crucial role in aerosol formation. Particularly, the higher nitrate concentration in city aloft than at the ground level during daytime was mainly due to the enhanced gas-particle partitioning driven by ALW and particle acidity. The vertical profiles of organic aerosol (OA) factors varied more differently in the urban boundary layer. Although the ubiquitous decreases in primary OA with the increase in height were mainly due to the influences of local emissions and vertical convection, the vertical differences in oxygenated OA between summer and winter may be related to the photochemical processing of different biogenic and anthropogenic volatile organic compounds. The single-scattering albedo, brown carbon, and absorption Ångstrom exponent of aerosol particles also presented different vertical profiles between day and night due to the vertical changes in aerosol chemistry.

Study was done to determine mean of radius of curve of spee in different vertical pattern Curve of Spee is a naturally occurring phenomenon in the human dentition. This normal occlusal curvature is required for an efficient masticatory system. Exaggerated curve of Spee is frequently observed in dental malocclusions with deep overbites.1 Such excessive curve of Spee alters the muscle imbalance, ultimately leading to improper functional occlusion.It was cross sectional study design with 211 patients from department of Orthodontics, dental OPD Karachi Medical and Dental College, Abbassi Shaheed Hospital, Karachi, Pakistan. The data collection procedure was non-probability consecutive. Sampling procedure had inclusion criteria to be followed that included, No previous history of orthodontic treatment, healthy subjects having complete dentition, second molars erupted and except for third molars no other maxillary and mandibular teeth were absent. The exclusion criteria was also set for study including, any syndromic or cleft lip and palate subject will not be included, participants with history of trauma and patients with facial asymmetry. All the patients were examined by researcher. After thorough history and clinical examination for evaluating the inclusion and extrusion criteria patients were recruited for the study. All measurements were recorded on a predesigned Performa. [ABSTRACT FROM AUTHOR]

This study was done to determine mean of radius of curve of spee in different vertical patterns. It was cross sectional study design with 106 patients from department of Orthodontics, dental OPD Karachi Medical and Dental College, Abbassi Shaheed Hospital, Karachi, Pakistan. The data collection procedure was non–probability consecutive. After thorough history and clinical examination for evaluating the inclusion and extrusion criteria patients were recruited for the study. All measurements were recorded on a predesigned Performa. Frequency test was applied for radius of curve of spee and mean value was 33, 56 and 17 for high, normal and low angle respectively. Test shows that highest angle noted is normal that has 56 value for collected data. Low angle is rarely present that is 17 and high angle is present in between with values of 33. It was found that value of radius of curve of spee was highest for normal angle followed by high angle then low angle subjects [ABSTRACT FROM AUTHOR]

Objectives: Orthopantomographs are commonly used for diagnosis in clinical dentistry. Although the manufacturers claim a constant magnification effect, the reliability of measuring dimensions on the panoramic radiographs is not clear. The aim of this study was to evaluate the accuracy of measuring vertical dimensions in the posterior mandibular area on digital orthopantomographs., Materials and Methods: A retrospective survey of 20 orthopantomographs with unrestored implants (only with cover screw) in the mandibular posterior region (molars and premolars) was conducted. All radiographs were taken using the same machine by skilled technicians. Two examiners were asked to measure the vertical dimension of the implants seen on the radiographs viewed using two differently sized display screens. Inter-examiner and intra-examiner reliability tests were performed. Differences between the measured length and the actual length using each screen type were compared., Results: High coefficients of reliability were observed on intra- and inter-examiner correlation. The overall reliability of measuring the vertical dimensions of implants between both examiners for the large screen and the small screen were 97.4% (Cronbach's alpha 0.993) and 94.0% (Cronbach's alpha 0.984), respectively. There were no significant differences between the errors seen with either the large screen or the small screen, when each of them was compared to the original length (P = 0.146)., Conclusion: This study shows that vertical dimensions in the posterior mandibular region (molar and premolars) can be reliably measured on an orthopantomograph using a calibrated machine and special software.