Mouth Region Research Articles

A Model of Microwave Emission from Mouth Regions of Arctic Rivers Providing for Radiometer Pixel Land Contamination

The paper presents a model of microwave emission from mouth regions of Arctic rivers taking into account radiometer pixel contamination by land. Modeling of seasonal and interannual dynamics of brightness temperature of different regions of the Yenisei Bay is performed on the example of MIRAS radiometer data from the SMOS satellite. The necessity of considering the coastal zone in brightness temperature modeling in the studied regions is shown. Comparison of the model calculations with SMOS L1C data has shown a good agreement. Analysis of model calculations and satellite data has allowed us to determine the location of the fresh and salt water mixing zone in the Yenisei Bay during the ice period, provided that the model takes into account the coastal zone captured by the radiometer pixel.

Efficacy of electrical stimulation of the zygomaticus muscle in complete facial paralysis: evidence from facial grading and automated image analysis

Surface Functional Electrical Stimulation (FES) is a well-studied intervention for multiple muscular disorders. However, it is still controversially discussed as a complementary therapy for complete facial paralysis. The aim of this intervention is to test a daily home-based ES concept as a pilot study regarding safety, feasibility, and effects on facial functionality and symmetry. In a prospective single-centre pilot study, 10 patients (median 61 years, denervation 130 d) with complete peripheral facial paralysis performed home-based FES of the affected lateral mouth region Stimulation parameters, facial paralysis scores and standardised photographs were assessed in monthly follow-ups. No serious adverse events appeared. Stimulation parameters could be constantly increased indicating effective muscle training while subjectively perceived functionality of the face improved. Thus, smile angle of the paralysed side improved as well. FES is a safe therapy model for application in facial nerve paralysis patients. A feasible stimulation protocol could be applied, which improved the functionality and symmetry of the stimulated facial region. A future controlled, randomised and double-blind follow-up study is needed to investigate these initial results in a further evolved replicable setting.

Deceleration of denervated facial muscle atrophy through functional electrical stimulation: a sonographic quantification in patients with facial nerve paralysis.

Functional Electrical Stimulation (FES) is an established intervention for a range of muscular and neurological disorders that has already been studied in numerous publications. However, its application to Peripheral Facial nerve Paralysis (PFP) still needs to be sufficiently investigated. As the first approach known to the authors, this study examines the effect of FES on the facial muscles in complete PFP using ultrasonography as a means of observation. In a prospective single-center observational pilot study, ten patients with complete PFP, confirmed by needle-electromyography (EMG), performed FES of the affected lateral mouth region at home twice daily for 20 minutes. The facial muscles' Cross-Sectional Area (CSA) was regularly assessed using sonographic quantification. While the CSA of most non-stimulated muscles decreased considerably during ongoing paralysis, a significant CSA increase of the Zygomaticus Muscle (ZYG), which was regularly subjected to FES, could be demonstrated. FES can halt the atrophy of denervated ZYG and potentially other facial muscles. Further investigations with a more significant patient collective are recommended. From now on, FES could be established as an additive method in the non-invasive treatment of PFP.

In the eye and mind of the beholder: The effects of familiarisation on the perception of atypical infant facial configurations.

Perception of infant faces plays a crucial role in adult-infant caretaking behaviour, with adults being found to demonstrate a reliable attraction towards infant faces over other stimuli. When affected by a congenital facial malformation such as cleft lip and/or palate, however, adults' visual scanning patterns and subjective appraisal of these faces have been found to be adversely affected. Little past work has explored how an observer's prior experience with this specific malformation might play a role in the perception of cleft-affected infant faces. To this end, two groups of adult female participants were recruited and presented with 48 images of infant faces (24 typical, 24 cleft-affected) with one group subjected to novel, purpose-built familiarisation training, where participants were exposed to infant cleft lip/palate related visual and informational stimuli prior to testing (n = 43). Eye gaze patterns and subjective "cuteness" ratings from this group were compared with an age matched control group which received no training (n = 41). No between group differences were found for "cuteness" ratings or eye gaze patterns to the cleft-affected mouth area in isolation, however, a significant negative relationship was found between gaze duration to the mouth region of cleft-affected images and subjective "cuteness" ratings, for control participants only. Notably, this relationship was not observed for the familiarised participants, suggesting their modified prior experience attenuated the effect that visual processing had on subjective appraisal of cleft-affected faces, when these two factors were assessed in tandem. Our findings suggest it is possible to attenuate the typically observed aversive behaviour towards cleft-affected infant faces. This may have implications for clinical practice concerned with supporting adult caretaking of malformation-affected infants and policies related to increasing positive perception of congenital facial disfigurement.

Comparison of Postorthodontic Occlusal Force Distributions between Nonextraction and Extraction Treatment Approaches of Premolars for Orthodontic Treatment by Using T-Scan III System.

To compare bite force distributions in corresponding mouth regions between postorthodontic patients who underwent nonextraction and extraction approaches using the T-Scan III system (Tekscan, Inc, Massachusetts, United States). Thirty-six postorthodontic patients were divided into two groups: (1) 18 subjects with the nonextraction treatment and (2) 18 subjects with the extraction of four first-premolar treatments. The measurements were performed using the T-Scan to collect the occlusal bite force at the maximal intercuspal position to generate the bite force in the anterior region (incisors and canines) and posterior region (premolars and molars), the bite force in individual teeth, and the anteroposterior bite force ratio (A-P ratio). The mean bite force in each region, individual teeth, and the A-P ratio were compared between the two groups by the Mann-Whitney's U-tests. Within-group comparisons of the mean bite force in each region were performed using Wilcoxon's signed rank tests. The bite force in anterior and posterior regions, and the A-P ratio of the nonextraction group show no significant difference compared with the extraction group (p > 0.05). For individual teeth (central incisors, lateral incisors, canines, second premolars, first molars, and second molars), each tooth exhibited nonsignificantly different bite forces (p > 0.05) except for the second molars. The second molars in the nonextraction group had significantly less bite force than in the extraction group (p = 0.001). The comparison of occlusal bite force between the right and left sides showed that in the nonextraction group, the right side had significantly greater force (p < 0.05). In the extraction group, there was no significant difference between the sides (p > 0.05). Both nonextraction and extraction orthodontic treated patients exhibited the similar bite force distribution patterns in regions and individual teeth except for the higher occlusal force on the second molars in the extractions compared with the nonextractions.

25 years into research with the Méhes Scale, a comprehensive scale of modern dysmorphology

It has been recognized that subtle, cosmetically insignificant anomalies tend to occur cumulatively in diseases with neurodevelopmental origin. These visible signs of morphogenesis errors are called minor physical anomalies (MPAs), serving as sensitive external markers of abnormal neurodevelopment. After the introduction of the Waldrop Scale, the studies conducted on MPAs in diseases with neurodevelopmental origin gave conflicting results. It has been debated that this discrepancy can be – at least partly – attributed to the use of the Waldrop Scale. Understanding the need of a comprehensive scale of MPAs that also differentiates according to the time of development, Hungarian pediatrician professor of University of Pécs, Károly Méhes developed a scale with 57 items, the only scale differentiating minor malformations from phenogenetic variants. With the use of the Méhes Scale, our research group has been investigating the role of abnormal neurodevelopment in different neuropsychiatric and neurologic disorders since 1997. 25 years into our research, in this review we summarize the results of our 18 research articles on MPAs in different diseases. We have found an increased number of MPAs, especially in the head and mouth region, in patients with schizophrenia, bipolar disorder, Tourette syndrome, autism and many epilepsy syndromes, fortifying the role of abnormal neurodevelopment in these diseases. Moreover, an increased number of MPAs was detected among the first-degree relatives of patients with schizophrenia and bipolar I disorder, supporting the hypothesis about MPAs being endophenotypic trait markers.

Observer-generated maps of diagnostic facial features enable categorization and prediction of emotion expressions

According to one prominent model, facial expressions of emotion can be categorized into depicting happiness, disgust, anger, sadness, fear and surprise. One open question is which facial features observers use to recognize the different expressions and whether the features indicated by observers can be used to predict which expression they saw.We created fine-grained maps of diagnostic facial features by asking participants to use mouse clicks to highlight those parts of a face that they deem useful for recognizing its expression. We tested how well the resulting maps align with models of emotion expressions (based on Action Units) and how the maps relate to the accuracy with which observers recognize full or partly masked faces.As expected, observers focused on the eyes and mouth regions in all faces. However, each expression deviated from this global pattern in a unique way, allowing to create maps of diagnostic face regions. Action Units considered most important for expressing an emotion were highlighted most often, indicating their psychological validity. The maps of facial features also allowed to correctly predict which expression a participant had seen, with above-chance accuracies for all expressions. For happiness, fear and anger, the face half which was highlighted the most was also the half whose visibility led to higher recognition accuracies.The results suggest that diagnostic facial features are distributed in unique patterns for each expression, which observers seem to intuitively extract and use when categorizing facial displays of emotion.

Пространственная и временная изменчивость нанофитопланктона в фьордах Западного Шпицбергена в летний период.

The paper presents the results of studies of nanophytoplankton in the fjords of Western Spitsbergen in the summer of 2001, 2002, 2003 and 2017. It is shown that the water area of each fjord is characterized by a fragmentation of the community of planktonic nanoalgae with depth and from the apex to the mouth region, as well as a deepening of the core of maximum abundance at the exit from the fjord, regardless of the density structure of the water column. For fjords of different latitudinal locations, a decline in integral indicators, a lowering of the community core from the surface horizon, and the replacement of large size fractions by cells smaller than 5 μm in the northern direction as the water temperature increases were recorded. In terms of interannual variability, the total abundance and structural organization of nanophytoplankton were determined by the degree of temperature stratification. In the summer of 2017 an increase in the absolute values of abundance and biomass by 1–2 orders of magnitude compared to zero years was revealed, while maintaining the main features of the structural organization of the community.

Non-dental odontodes in the masticatory apparatus of †pycnodonts (Osteichthyes, Actinopterygii)

ABSTRACT Two specimens of the pycnodont Haquelpycnodus picteti from the Cenomanian (Late Cretaceous) of Lebanon possess small non-dental odontodes flanking the teeth inside the oral cavity. These odontodes are distributed labially with respect to the vomerine and prearticular dentition, corresponding to the internal face of the cheek and in front of the maxilla. They have no relation to any of the bones in the mouth region and were situated in the endo-oral mucosa. This dentition pattern resembles that of the earliest osteichthyans and stem-gnathostomes. SEM-investigation of the non-dental odontodes demonstrates a thick layer of orthodentine covered by two thin outer layers of acrodin. The microchemical composition of these odontodes corresponds to those of the dermal scales (derived from odontodes) that are distributed in the integument of the same examined specimen. Both morphology, ultrastructure, and topographic relationships demonstrate that these structures are dermal and not dental odontodes. The reappearance of dermal odontodes in the dentition of individual specimens of Haquelpycnodus thus reflects the latent capacity of the endo-oral mucosa to form non-dental odontodes. These odontodes probably exerted lateral pressure to the content within the oral cavity, which took place synchronously with the prehensile movements of the incisors.

Spatio-temporal human snow leopard (Panthera uncia) conflicts and mitigation measures in Baltistan - free-livestock grazing pastoral areas

Apex predators are essential for maintaining ecosystem balance by controlling biotic communities. The spatio-temporal grazing of livestock in pastoral areas can pose threats to endangered carnivores and their prey resulting in resource competition, conflicts and increased disease transmission. Our research aimed to assess the spatio-temporal distribution of snow leopards and livestock determine factors causing snow leopard-livestock conflicts identify seasonal conflict zones through public claims and interviews and evaluate conservation benefits and challenges. In this study, camera traps were used in 20 villages of Baltistan from November to April resulting in 720 snow leopard sightings and 8277 livestock events. Snow leopards preyed on 195 livestock in the 2022–2023 period resulting in an estimated loss of $225,004.51 USD including sheeps, goats, cows and yaks.We utilized the Generalized Linear Regression Model to examine snow leopard attacks finding that the timing of attacks was not significant. Proximity to predator-proofed corrals, traditional corrals, bite marks and distance to the nearest village or shepherd huts were positively correlated with attacks, while small stock body size was not significant. Through 110 public interviews we discovered that awareness campaigns and avoidance strategies successfully mitigated human-snow leopard conflicts. In conclusion, our results found that livestock attacks occur in pastures during both day and night with the size and sex of the livestock affecting the likelihood of attacks. Snow leopard attacks were linked to increased grazing and poorly constructed corrals. Snow leopards targeted vulnerable areas of their prey including the neck, mouth, ears and anal region. Compensation claims and field visits were used to identify conflict areas and public perception. In the future research should prioritize the use of camera traps to study prey and snow leopard density, grazing effects, food habits using genetic tools and sex determination.

Rapid detection of ingested acetaminophen on face mask by ambient ionization tandem mass spectrometry

BackgroundA regular face mask is comprised of three layers for resisting moisture, filtration, and absorbing oral fluid, respectively. Since the polymers with different polarities are used to make the layers, a face mask can be used as a sampling tool to retain polar or non-polar chemical and biochemical substances in the exhaled breath. In this study, thermal desorption-electrospray ionization tandem mass spectrometry (TD-ESI/MS/MS), an ambient ionization mass spectrometric technique, was used to detect trace acetaminophen that were exhaled and retained on the surface of different layers in a face mask. ResultsWith probe sampling combined with TD-ESI/MS/MS, the acetaminophen ion signal can be detected at the mouth/nostril region of the face mask after taking the acetaminophen tablet. The experimental results were similar to previous studies for the detection of acetaminophen in blood over time using LC/MS/MS. In addition, the intensities of acetaminophen on different layers of the face mask could reveal the differing distributions of exhaled acetaminophen on each layer. To explore the distribution of acetaminophen on the face mask surface, multiple probes were used to collect samples from different locations of the face mask for analysis. The molecular mapping of acetaminophen on the face mask was rendered by scaling the analyte ion signal intensity based on a temperature color gradient. The cartography showed a higher acetaminophen ion signal distribution on the mouth and nostril regions than in other areas of the face mask. SignificanceOwing to the advantages of a simple, sensitive, and non-invasive sampling approach, drug monitoring could be potentially performed to provide useful information for anti-drug of precision medicine in the future.

An investigation on the face inversion effect in deaf children.

The face inversion effect is an important indicator of holistic face perception and reflects the developmental level of face processing. This study examined the face inversion effect in deaf or hard of hearing (DHH) children aged 7-17 using the face dimensions task. This task uses photographic images of a face, in which configural and featural information in the eye and mouth regions have been parametrically and independently manipulated. The study aimed to discuss the effect of face inversion on facial processing in DHH children, including two aspects of information processing types (configural versus featural) and processing regions (eyes versus mouth) and compared the results with hearing children. The results revealed that DHH children aged 7-17years exhibit significant face inversion effect, with disruptions observed in both the featural and configural processing of eyes and mouths when faces were inverted. Configural processing was more affected by inversion than featural processing in all children, with larger differences observed in DHH children than in hearing children. This supports the dual-mode hypothesis of holistic face processing. Age correlations were observed in the sensitivity of DHH children to face inversion effect but not among hearing children. The inversion effect of configural mouth processing decreases with age in DHH children.

Do Children with High Callous-Unemotional Traits Have Attentional Deficits to Emotional Stimuli? Evidence from a Multi-Method and Multi-Informant Study.

Callous-unemotional (CU) traits in children and adolescents are linked to severe and persistent antisocial behavior. Based on past empirical research, several theoretical models have suggested that CU traits may be partly explained by difficulties in correctly identifying others' emotional states as well as their reduced attention to others' eyes, which could be important for both causal theory and treatment. This study tested the relationships among CU traits, emotion recognition of facial expressions and visual behavior in a sample of 52 boys referred to a clinic for conduct problems (Mage = 10.29years; SD = 2.06). We conducted a multi-method and multi-informant assessment of CU traits through the Child Problematic Traits Inventory (CPTI), the Inventory of Callous-Unemotional (ICU), and the Clinical Assessment of Prosocial Emotions-Version 1.1 (CAPE). The primary goal of the study was to compare the utility of these methods for forming subgroups of youth that differ in their emotional processing abilities. An emotion recognition task assessed recognition accuracy (percentage of mistakes) and absolute dwell time on the eyes or mouth region for each emotion. Results from repeated measures ANOVAs revealed that low and high CU groups did not differ in emotion recognition accuracy, irrespective of the method of assessing CU traits. However, the high CU group showed reduced attention to the eyes of fearful and sad facial expressions (using the CPTI) or to all emotions (using the CAPE). The high CU group also showed a general increasein attention to the mouth area, but only when assessed by the CAPE. These findings provide evidence to support abnormalities in how those elevated on CU traits process emotional stimuli, especially when assessed by a clinical interview, which could guide appropriate assessment and more successful interventions for this group of youth.

Detection and Segmentation of Mouth Region in Stereo Stream Using YOLOv6 and DeepLab v3+ Models for Computer-Aided Speech Diagnosis in Children

This paper describes a multistage framework for face image analysis in computer-aided speech diagnosis and therapy. Multimodal data processing frameworks have become a significant factor in supporting speech disorders’ treatment. Synchronous and asynchronous remote speech therapy approaches can use audio and video analysis of articulation to deliver robust indicators of disordered speech. Accurate segmentation of articulators in video frames is a vital step in this agenda. We use a dedicated data acquisition system to capture the stereovision stream during speech therapy examination in children. Our goal is to detect and accurately segment four objects in the mouth area (lips, teeth, tongue, and whole mouth) during relaxed speech and speech therapy exercises. Our database contains 17,913 frames from 76 preschool children. We apply a sequence of procedures employing artificial intelligence. For detection, we train the YOLOv6 (you only look once) model to catch each of the three objects under consideration. Then, we prepare the DeepLab v3+ segmentation model in a semi-supervised training mode. As preparation of reliable expert annotations is exhausting in video labeling, we first train the network using weak labels produced by initial segmentation based on the distance-regularized level set evolution over fuzzified images. Next, we fine-tune the model using a portion of manual ground-truth delineations. Each stage is thoroughly assessed using the independent test subset. The lips are detected almost perfectly (average precision and F1 score of 0.999), whereas the segmentation Dice index exceeds 0.83 in each articulator, with a top result of 0.95 in the whole mouth.

Head and neck tumors detected in dogs and cats between 2011 and 2021: A retrospective study

The aim of this study is to determine and compare the distribution, localization, breed, age and gender incidences of head and neck region tumors by years, by evaluating the results of dog-cat biopsies and/or operation material brought to Ankara University, Faculty of Veterinary Medicine, Department of Pathology between the years 2011 and 2021. In the study, 244 (15.9%) of 1533 tumors diagnosed in dogs and cats between 2011 and 2021 belonged to the head and neck region, of which 159 were in dogs and 85 in cats. Dogs with tumors were generally more than 6 years old (n=108) and cats were mostly 1 year old and older (n=75). In the head and neck region tumors observed in dogs, malignant and benign tumors of epithelial origin were most common (n=81; 50.9%), with sebaceous tumors (n=22) being the most common, and mostly observed around the eyes (n=26), while malignant and benign tumors of mesenchymal origin were most commonly found in the mouth region. Among the tumors of this region, epithelial tumors were mostly encountered in cats (n=39, 45.8%), and 51.2% of the epithelial tumors were squamous cell cancer (n=20), with epithelial tumors being the most common in the mouth (n=12) and nose (n=9). As a result, epithelial malignant and benign tumors were mostly seen in the eyes, and mesenchymal malignant and benign tumors were detected in the mouth. Among tumor types, papilloma in benign tumors and squamous cell carcinoma in malignant tumors were noted.

The super‐recogniser advantage extends to the detection of hyper‐realistic face masks

AbstractHyper‐realistic silicone masks provide a viable route to identity fraud. Over the last decade, more than 40 known criminal acts have been committed by perpetrators using this type of disguise. With the increasing availability and bespoke sophistication of these masks, research must now focus on ways to enhance their detection. In this study, we investigate whether super‐recognisers (SRs), people who excel at identity recognition, are more likely to detect this type of fraud, in comparison to typical‐recogniser controls. Across three tasks, we examined mask detection rates in the absence of a pre‐task prompt (covert task), and again after making participants aware of their use in criminal settings (explicit task). Finally, participants were asked to indicate which aspects of the masks could support their detection (regions of interest task). The findings show an SR advantage for the detection of hyper‐realistic masks across the covert and explicit mask detection tasks. In addition, the eye, mouth, and nose regions appear to be particularly indicative of the presence of a mask. The lack of natural skin texture, proportional features, expressiveness, and asymmetry are also salient cues. The theoretical and applied implications of these findings are discussed.

Face masks facilitate discrimination of genuine and fake smiles – But people believe the opposite

It seems a foregone conclusion that face mask-wearing hinders the interpretation of facial expressions, increasing the risk of interpersonal miscommunication. This research identifies a notable counter-case to this apparent truism. In multiple experiments, perceivers were more accurate distinguishing between genuine and fake smiles when the mouth region was concealed under a mask versus exposed. Masks improved accuracy by shielding perceivers from the undue influence of non-diagnostic cues hidden behind masks. However, perceivers were unaware of the advantage bestowed by masks, holding, instead, the misbelief that masks severely obscure the distinction between genuine and fake smiles. Furthermore, these patterns proved to be culturally invariant rather than culturally contingent, holding true for both Westerners and Easterners.

Hydro-ecological modelling of a hypersaline lagoon ecosystem (Pulicat) in Southeast coast of India

Climate change impacts the coastal lagoons and can affect various species reproductive cycles, feeding habits, and survival. Due to natural factors, the ecosystem habitat at Pulicat Lagoon on the east coast of India is under severe stress. This study assesses the ecosystem using a numerical model and field-collected physical, chemical, biological, and meteorological data for 2018 and 2019. A coupled hydro-ecological model was used to analyze circulation features, biological and chemical interactions, and transformation processes. The study indicates that high abnormalities in the lagoon ecosystem are caused by less exchange of fresh/coastal water from river sources and sea mouths due to less rainfall during the study period. The model output depicts the salinity variation from 15 to 58 PSU in different seasons of 2018 and 2019. Furthermore, high concentrations of Chl-a ranged from 50 μg/L to 95 μg/L during the monsoon and post-monsoon seasons, triggering phytoplankton C (70–350 mg/m3) and zooplankton C (9–43 mg/m3) at the Lagoon, resulting in an algal bloom. The monsoonal shift of Chlorophyte (9.52%–9.68%), Cyanobacteria (13.22%–14.95%), Diatoms (66.08%–63.87%), and Dinoflagellates (11.18%–11.51%) is observed in the biological field, with Diatom showing the highest abundance (65%). As a result, appropriate scenario-based model studies were conducted to conserve and strengthen the ecosystem during such extreme events. The model studies suggest that widening the lagoon inlet (800m) with a depth of 5 m (3 km length) increases the optimal tidal exchange to the ecosystem. The model output demonstrates the optimal exchange that normalizes the salinity from 12 to 34 PSU from the inner Lagoon to the mouth region. This study will support environmental authorities in conserving the ecosystem through proper management adaptations.

The other-ethnicity effect in facial recognition of Tibetan and Han individuals: Evidence from behavioural and eye-movement data.

Studies have shown that facial recognition among racial groups exhibits not only an other-race effect but also an other-ethnicity effect within the same racial group. To explore differences in facial recognition and visual scanning patterns due to the other-ethnicity effect, behavioural and eye-movement data were used to investigate the other-ethnicity effect in the facial perception of Tibetan and Han Chinese individuals and whether the visual scanning patterns varied between them. Behavioural data revealed an other-ethnicity effect on facial recognition of Tibetan and Han individuals. Eye-movement data indicated that Tibetan and Han individuals fixated more on the eye and mouth regions when recognising Han faces and on the eye and nose regions when recognising Tibetan faces. The other-ethnicity effect appeared to influence facial recognition in Tibetan and Han individuals, who adopted similar visual scanning patterns when scanning the faces of individuals of their own ethnicity and those of other ethnicities.

Effects of the deformation and size of the upper airway on the deposition of aerosols

Aerosol drug delivery in the human airway is significantly affected by the morphology and size of the airway. This work developed a CFD-DEM model to simulate and analyze air flow and powder dynamics in combined inhaler-airway systems with different degrees of airway deformation (non-deformed, 50%, and 75% deformed) and sizes (adult, 0.80, and 0.62 scaled). The airways were generated based on a regular airway constructed from the MRI images through finite element method (for deformed airways) or scaling-down (for smaller airways). The airways were connected to Turbuhaler® through a connector. The results showed that under the same flow rate, the variation in the airway geometry and size had a minimum impact on the flow field and powder deposition in the device and the connector. However, deformation caused more particle deposition in the deformed region. Notably, the airway with 50% deformation had the most particles passing through the airway with the largest particle sizes due to its lower air velocity in the deformed area. Reducing airway size resulted in more powder deposition on the airway, particularly at the pharynx and mouth regions. This was because, with the same flow rate, the flow velocity in the smaller airway was higher, causing more particle–wall collisions in the mouth and pharynx regions. More importantly, the deposition efficiency in the 0.62-scaled airway was significantly higher than the other two airways, highlighting the importance of the different administration of aerosol drugs for young children.