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Objective: This study investigated maxillary skeletal structures and dentition shape and size in subjects with palatally impacted maxillary canines using geometric morphometric analysis. Methods: In this cross sectional study, cone-beam computed tomography images for 40 subjects (22 females, 18 males, mean age 16 years) with palatally impacted canines and 40 subjects (22 females, 18 males, mean age 17 years) with nondisplaced canines were included from a single radiology center. On cone-beam computed tomography images the nasal cavity, palate, sinus, alveolar crest, maxillary lateral walls, and dentition were landmarked by three examiners. Landmarked CBCT images were evaluated for shape using geometric morphometric analysis by performing procrustes superimpositions and principle component analysis. Shape differences were further investigated by using logistic regression and linear regression analyses. Results: Principle component analysis revealed subjects with palatally impacted maxillary canines had a nasal cavity that was more constricted, the palate was more deeply vaulted and constricted, the sinus extended less vertically, canines were wider both mesial-distally and buccal-palatally in relation to length, and the lateral incisors were more narrow both mesial-distally and buccal-palatally in relation to length. Logistic regression depicted five variables that were associated with palatally impacted maxillary canines: Maxillary basal width at the first molar area, palatal depth, canine centroid size, lateral incisor centroid size, and central incisor centroid size (p<.05). Conclusions: In palatally displaced maxillary canines, both the canine and lateral incisor size was diminished while the central incisor size was comparatively increased. The nasal cavity was constricted, the palate perimeter was constricted, the palate was more deeply vaulted, the sinus extended less vertically, and the basal maxillary width was constricted at the first molar area.

In this study, a brass or glass spherical impactor vertically penetrating into a granular bed composed of mono-sized spherical or elongated particles was simulated with three-dimensional (3D) discrete element method (DEM). Good agreement of the particle masses in the cup before and after penetration can be found in the simulations and experiments. The effects of particle length (Lp), friction coefficient, and particle configuration on the penetration depth of the impactor, ejecta mass, and solid volume fraction describing the response of the granular bed are discussed. The penetration depth is negatively correlated with Lp as the corresponding solid volume fraction of the granular bed decreases. A smaller friction coefficient leads to a larger penetration depth of the impactor and more ejection of particles. When the impactor is penetrating the Lp = 10 mm elongated particles, the penetration depth is negatively correlated to the order parameter and solid volume fraction.

Impacted incisors can pose significant esthetic and functional challenges for patients. Various treatment approaches have been proposed. The 2x4 orthodontic appliance is one of the most effective treatment plans for aligning the teeth. This article presents two cases showing surgical traction's effectiveness using the 2x4 orthodontic appliance in managing impacted incisors. The results of this case series demonstrated successful outcomes in terms of impacted incisor alignment and overall occlusion. Patients exhibited improved esthetics and function. Therefore, Surgical traction of impacted incisors using the 2x4 orthodontic appliance can be a viable and effective treatment approach.&nbsp

Introduction: Anterior teeth are valuable for aesthetics, speech and mastication . Their absence, impaction and/or delayed eruption create significant distress often leading to early presentation to the dental office. This study presents an audit of the management of impacted anterior teeth that presented at a tertiary level dental clinic. The periodontal outcomes of the aligned teeth were also reported. Methods: This is an observational study spanning a nine-year period. Demographic data, clinical presentation as well as post alignment dental and periodontal status of the impacted teeth were assessed. Data was analysed using the Statistical Package for Social Sciences (SPSS) version 26. Fisher’s exact test and paired samples T-test were used for categorical and continuous variables respectively. Significance was set at P < 0.05. Results: Twenty-eight (1.76%) cases presenting with failed eruption of thirty-two anterior teeth were found during the period under review. Eight patients were treated by extraction, orthodontic treatment and space closure or prosthetic replacement with a mean treatment time of 2.83 ± 2.66 years. Thirteen patients completed treatment by orthodontic alignment with mean alignment time of 1.4 ± 1.5 years and treatment time of 3.6 ± 2.5 years. There was significant difference in the post-operative root length of aligned teeth compared to their normal antimeres (p < 0.005). Conclusion: Patients with impacted anterior teeth presented later than was beneficial for spontaneous alignment of their teeth. The average 1.5mm loss of root length observed was not detrimental to the anatomical retention or function of the aligned teeth. There is need for more enlightenment with regards to early presentation for dental problems to avoid expensive and time-consuming treatments.

Introduction: Anterior teeth are valuable for aesthetics, speech and mastication . Their absence, impaction and/or delayed eruption create significant distress often leading to early presentation to the dental office. This study presents an audit of the management of impacted anterior teeth that presented at a tertiary level dental clinic. The periodontal outcomes of the aligned teeth were also reported. Methods: This is an observational study spanning a nine-year period. Demographic data, clinical presentation as well as post alignment dental and periodontal status of the impacted teeth were assessed. Data was analysed using the Statistical Package for Social Sciences (SPSS) version 26. Fisher’s exact test and paired samples T-test were used for categorical and continuous variables respectively. Significance was set at P < 0.05. Results: Twenty-eight (1.76%) cases presenting with failed eruption of thirty-two anterior teeth were found during the period under review. Eight patients were treated by extraction, orthodontic treatment and space closure or prosthetic replacement with a mean treatment time of 2.83 ± 2.66 years. Thirteen patients completed treatment by orthodontic alignment with mean alignment time of 1.4 ± 1.5 years and treatment time of 3.6 ± 2.5 years. There was significant difference in the post-operative root length of aligned teeth compared to their normal antimeres (p < 0.005). Conclusion: Patients with impacted anterior teeth presented later than was beneficial for spontaneous alignment of their teeth. The average 1.5mm loss of root length observed was not detrimental to the anatomical retention or function of the aligned teeth. There is need for more enlightenment with regards to early presentation for dental problems to avoid expensive and time-consuming treatments.

Dentigerous cysts are defined as developmental odontogenic cysts, which surround the crown of an impacted tooth. It is caused by fluid  accumulation between the reduced enamel epithelium and the enamel surface, resulting in a cyst with the tooth crown located within the lumen. This paper reviews the pathogenesis, clinical features and the behaviour of dentigerous cyst. It also presents a case of a slow growing, painless swelling in the maxillary incisal region of 3 years duration. Detailed clinical, radiological and histopathological investigations aided the definitive diagnosis of dentigerous cyst. The cystic mass was enucleated with the impacted tooth in situ under local anesthesia. The operative site healed uneventfully and a removable partial  denture was fabricated to improve aesthetics, speech and masticatory function. &nbsp

Dentigerous cysts are defined as developmental odontogenic cysts, which surround the crown of an impacted tooth. It is caused by fluid  accumulation between the reduced enamel epithelium and the enamel surface, resulting in a cyst with the tooth crown located within the lumen. This paper reviews the pathogenesis, clinical features and the behaviour of dentigerous cyst. It also presents a case of a slow growing, painless swelling in the maxillary incisal region of 3 years duration. Detailed clinical, radiological and histopathological investigations aided the definitive diagnosis of dentigerous cyst. The cystic mass was enucleated with the impacted tooth in situ under local anesthesia. The operative site healed uneventfully and a removable partial  denture was fabricated to improve aesthetics, speech and masticatory function. &nbsp

Odontomas are considered to be developmental anomalies rather than true neoplasms. They have been termed compound composite odontomas when there is at least superficial anatomic similarity to normal teeth. A supernumerary tooth in the maxillary anterior region is termed a mesiodens. This case report presents an unusual case of occurrence of a compound composite odontome along with a mesiodens, causing impaction of permanent central incisor in a 14 year old boy. Both odontome and mesiodens were surgically removed along with the impacted central incisor.

An inverted mandibular 3rd molar is rarely seen. The clinical and radiographic evaluation is necessary for the management of inverted teeth. This case report describes a rare case of inverted and impacted mandibular third molar which was surgically removed.

Mandibular canine impaction is considered as a rare condition. It is an even rarer phenomenon when both the mandibular canines are impacted. Bilateral mandibular canine with left maxillary canine impaction with incidence causes and management is discussed in a 13 year old boy.

Odontomas are considered to be developmental anomalies rather than true neoplasms. They have been termed compound composite odontomas when there is at least superficial anatomic similarity to normal teeth. A supernumerary tooth in the maxillary anterior region is termed a mesiodens. This case report presents an unusual case of occurrence of a compound composite odontome along with a mesiodens, causing impaction of permanent central incisor in a 14 year old boy. Both odontome and mesiodens were surgically removed along with the impacted central incisor.

An inverted mandibular 3rd molar is rarely seen. The clinical and radiographic evaluation is necessary for the management of inverted teeth. This case report describes a rare case of inverted and impacted mandibular third molar which was surgically removed.

Mandibular canine impaction is considered as a rare condition. It is an even rarer phenomenon when both the mandibular canines are impacted. Bilateral mandibular canine with left maxillary canine impaction with incidence causes and management is discussed in a 13 year old boy.

This study aimed to determine the frequency of gastric pathologies in donkeys (Equus africanus asinus) in the department of Córdoba, Colombia. Stomachs of 137 donkeys (73 intact males, 16 castrated males, and 48 females), aged between 1 to 25 years, were examined, characterized and photographed post mortem. Data on sex, age and pathology were reported on the respective forms and then digitized. Of the total population (137 donkeys), stomach ulcers and associated gastritis were found in 100% of the samples, antral edema in 56.9%, parasites (Trichostrongylus axei) in 10.2%, and impaction in 5.8%. Furthermore, Hemomelasma gastric was found in one stomach (0.7%). As a conclusion, 100% of the evaluated animals presented at least some kind of gastric pathology. Acute gastritis was the most frequent type (71.5%), followed in a smaller proportion by chronic gastritis (28.4%). The study showed a significant statistical dependence between age and the degree of injury to the glandular mucosa (p < 0.05). Thus, it evidenced a high incidence of gastric pathologies in donkeys in different livestock holdings in Córdoba, among which squamous ulcers are the most frequent ones, followed by acute gastritis and antral edema. For this reason, it is necessary to do more research and to raise awareness about the treatment of these pathologies in these animals., O objetivo deste estudo foi determinar a frequência de patologias gástricas em burros (Equus africanus asinus) do departamento de Córdoba, na Colômbia. Foram avaliados 137 estômagos de burros (73 machos inteiros, 16 machos castrados e 48 fêmeas), com um rango de idade entre 1 e 25 anos, nos quais o estômago foi avaliado, caracterizado e fotografado post mortem. Os dados de sexo, idade e patologia foram diligenciados nos formatos respectivos e posteriormente digitalizados. Da população total (137 burros), se encontraram úlceras gástricas e gastrite associada em 100 % das amostras, edema antral em 56,9 %, parasitas (Trichostrongylus axei) em 10,2 % e impactação em 5,8 %. Além do mais, em um estômago se encontrou Hemomelasma gastric (0,7 %). Conclui-se que o 100 % dos animais avaliados apresentou pelo menos algum tipo de patologia gástrica. O tipo de gastrite com mais incidência foi a gastrite aguda (71,5 %), seguida em menor proporção pela forma crônica (28,4 %). O estudo demonstrou que havia dependência estatística significativa entre a idade e o grau de lesão da mucosa glandular (p < 0,05). Deste modo, se percebe que existe uma elevada frequência de patologias gástricas nos burros das diferentes explorações pecuárias de Córdoba, onde as úlceras escamosas são as de maior frequência, seguidas das gastrites agudas e do edema antral; por isso é necessário realizar mais pesquisas e conscientização sobre o manejo destas patologias neste tipo de animais., El objetivo del presente estudio fue determinar la frecuencia de patologías gástricas en burros (Equus africanus asinus) del departamento de Córdoba, Colombia. Se evaluaron 137 estómagos de burros (73 machos enteros, 16 machos castrados y 48 hembras), con un rango de edad entre 1 y 25 años, en los cuales el estómago fue evaluado, caracterizado y fotografiado post mortem. Los datos de sexo, edad y patología fueron diligenciados en los formatos respectivos y posteriormente digitalizados. De la población total (137 burros), se encontraron úlceras gástricas y gastritis asociada en el 100 % de las muestras, edema antral en el 56,9 %, parásitos (Trichostrongylus axei) en el 10,2 % e impacción en el 5,8 %. Además, en un estómago se encontró Hemomelasma gastric (0,7 %). Se concluye que el 100 % de los animales evaluados presentó al menos algún tipo de patología gástrica. El tipo de gastritis con más incidencia fue la aguda (71,5 %), seguida en menor proporción por la forma crónica (28,4 %). El estudio demostró que había dependencia estadística significativa entre la edad y el grado de lesión de la mucosa glandular (p < 0,05). Así, se evidencia que existe una elevada frecuencia de patologías gástricas en los burros de las diferentes explotaciones pecuarias de Córdoba, en la cual las úlceras escamosas son las de mayor frecuencia, seguidas de las gastritis agudas y del edema antral; por eso es necesario realizar más investigaciones y concientización sobre el manejo de estas patologías en este tipo de animales.

This study aimed to determine the frequency of gastric pathologies in donkeys (Equus africanus asinus) in the department of Córdoba, Colombia. Stomachs of 137 donkeys (73 intact males, 16 castrated males, and 48 females), aged between 1 to 25 years, were examined, characterized and photographed post mortem. Data on sex, age and pathology were reported on the respective forms and then digitized. Of the total population (137 donkeys), stomach ulcers and associated gastritis were found in 100% of the samples, antral edema in 56.9%, parasites (Trichostrongylus axei) in 10.2%, and impaction in 5.8%. Furthermore, Hemomelasma gastric was found in one stomach (0.7%). As a conclusion, 100% of the evaluated animals presented at least some kind of gastric pathology. Acute gastritis was the most frequent type (71.5%), followed in a smaller proportion by chronic gastritis (28.4%). The study showed a significant statistical dependence between age and the degree of injury to the glandular mucosa (p < 0.05). Thus, it evidenced a high incidence of gastric pathologies in donkeys in different livestock holdings in Córdoba, among which squamous ulcers are the most frequent ones, followed by acute gastritis and antral edema. For this reason, it is necessary to do more research and to raise awareness about the treatment of these pathologies in these animals., O objetivo deste estudo foi determinar a frequência de patologias gástricas em burros (Equus africanus asinus) do departamento de Córdoba, na Colômbia. Foram avaliados 137 estômagos de burros (73 machos inteiros, 16 machos castrados e 48 fêmeas), com um rango de idade entre 1 e 25 anos, nos quais o estômago foi avaliado, caracterizado e fotografado post mortem. Os dados de sexo, idade e patologia foram diligenciados nos formatos respectivos e posteriormente digitalizados. Da população total (137 burros), se encontraram úlceras gástricas e gastrite associada em 100 % das amostras, edema antral em 56,9 %, parasitas (Trichostrongylus axei) em 10,2 % e impactação em 5,8 %. Além do mais, em um estômago se encontrou Hemomelasma gastric (0,7 %). Conclui-se que o 100 % dos animais avaliados apresentou pelo menos algum tipo de patologia gástrica. O tipo de gastrite com mais incidência foi a gastrite aguda (71,5 %), seguida em menor proporção pela forma crônica (28,4 %). O estudo demonstrou que havia dependência estatística significativa entre a idade e o grau de lesão da mucosa glandular (p < 0,05). Deste modo, se percebe que existe uma elevada frequência de patologias gástricas nos burros das diferentes explorações pecuárias de Córdoba, onde as úlceras escamosas são as de maior frequência, seguidas das gastrites agudas e do edema antral; por isso é necessário realizar mais pesquisas e conscientização sobre o manejo destas patologias neste tipo de animais., El objetivo del presente estudio fue determinar la frecuencia de patologías gástricas en burros (Equus africanus asinus) del departamento de Córdoba, Colombia. Se evaluaron 137 estómagos de burros (73 machos enteros, 16 machos castrados y 48 hembras), con un rango de edad entre 1 y 25 años, en los cuales el estómago fue evaluado, caracterizado y fotografiado post mortem. Los datos de sexo, edad y patología fueron diligenciados en los formatos respectivos y posteriormente digitalizados. De la población total (137 burros), se encontraron úlceras gástricas y gastritis asociada en el 100 % de las muestras, edema antral en el 56,9 %, parásitos (Trichostrongylus axei) en el 10,2 % e impacción en el 5,8 %. Además, en un estómago se encontró Hemomelasma gastric (0,7 %). Se concluye que el 100 % de los animales evaluados presentó al menos algún tipo de patología gástrica. El tipo de gastritis con más incidencia fue la aguda (71,5 %), seguida en menor proporción por la forma crónica (28,4 %). El estudio demostró que había dependencia estadística significativa entre la edad y el grado de lesión de la mucosa glandular (p < 0,05). Así, se evidencia que existe una elevada frecuencia de patologías gástricas en los burros de las diferentes explotaciones pecuarias de Córdoba, en la cual las úlceras escamosas son las de mayor frecuencia, seguidas de las gastritis agudas y del edema antral; por eso es necesario realizar más investigaciones y concientización sobre el manejo de estas patologías en este tipo de animales.

Objective: To analyze radiographic predictors for lower third molar eruption among subjects with different anteroposterior skeletal relations and of different age groups. Materials and Methods: In total, 300 lower third molars were recorded on diagnostic digital orthopantomograms (DPTs) and lateral cephalograms (LCs). The radiographs were grouped according to sagittal intermaxillary angle (ANB), subject age, and level of lower third molar eruption. The DPT was used to analyze retromolar space, mesiodistal crown width, space/width ratio, third and second molar angulation (alpha, gamma), third molar inclination (beta), and gonion angle. The LC was used to determine ANB, angles of maxillar and mandibular prognathism (SNA, SNB), mandibular plane angle (SN/MP), and mandibular lengths. A logistic regression model was created using the statistically significant predictors. Results: The logistic regression analysis revealed a statistically significant impact of 6 angle and distance between gonion and gnathion (Go-On) on the level of lower third molar eruption (P lt .001 and P lt .015, respectively). The retromolar space was significantly increased in the adult subgroup for all skeletal classes. The lower third molar impaction rate was significantly higher in the adult subgroup with the Class II (62.3%) compared with Class III subjects (31.7%; P lt .013). Conclusion: The most favorable values of linear and angular predictors of mandibular third molar eruption were measured in Class III subjects. For valid estimation of mandibular third molar eruption, certain linear and angular measures (beta angle, Go-On), as well as the size of the retromolar space, need to be considered.

This document contains detailed design information for assembly of a Dry Aerosol Deposition Device (DADD). This report is further to technical report AFRL-RX-TY-TP-2008-4617, ADA492108 and technical report AFRL-RX-TY-TR-2008-4592, ADA502105; work unit DODT0056. Growing threats of biological contamination of infrastructure and equipment led to the development of antimicrobial surfaces/coatings. Standard methods to test efficacy of such materials have applied microbial agents suspended in aqueous buffers. These surfaces, however, will likely be contaminated via aerosol exposure, so antimicrobial efficacy measurements using microbes deposited as aerosols will provide a more-representative test platform. A settling chamber is the most common method for depositing biological aerosols on surfaces, but it can impose limitations in respect to time and variability of sample loading. In prior work, a Dry Aerosol Deposition Device (DADD) was developed that uses impaction rather than settling to load surfaces with biological aerosols, providing a mechanism for rapid and highly reproducible loading of microorganisms onto surfaces. The DADD was tested with Bacillus atrophaeus spores and Staphylococcus aureus vegetative cells, deposited to glass coupons at concentrations exceeding 1 104 colony-forming units/cm2. The average coefficient of variation (CV) for sample-to-sample loading within experiments was 13.6% for spores and 6.1% for S. aureus cells. The DADD provides a mechanism to load coupons with a highly reproducible challenge of microorganisms. Preliminary validation was performed on glass coupons, but the device can also be used with aluminum, concrete or fabric samples. The DADD was demonstrated to be a relatively simple and inexpensive device that can easily be contained within a 4-foot biological safety cabinet.1

下顎第二小臼歯は様々な局所的要因により萌出が障害されるが，本研究では特発的な歯胚の方向異常により下顎第二小臼歯の萌出が障害された症例について検討を行い，臨床的対応法についてフローチャートを考案した。調査対象は1979年から2008年までに新潟大学医歯学総合病院小児歯科診療室で処置した，歯胚の方向異常に起因する下顎第二小臼歯萌出障害の11症例15歯で，診断時年齢は8歳Oか月～13歳11か月，片側性7例，両側性4例であった。15歯中14歯が遠心に傾斜しており，歯胚形成度が低いものほど遠心傾斜度が大きい傾向にあった(R>0.70)。また，片側怪と両側怪の2群に分けて傾斜度を比較すると，遠心傾斜度は片側性で有意に大きい値を示した(P<0.01)。診断後に全症例で先行乳歯を抜去していたが，傾斜度の大きい場合には，その後歯胚形成がすすんでも傾斜度はわずかに改善するのみで，初期歯根形成期から歯根長1/4形成期頃にかけて骨開窓や牽引，誘導等の複雑な対応を必要とする場合が多かった。したがって，形成遅延が顕著に認められる場合には，早期に先行乳歯を抜去すると保隙期間が長くなるため，下顎第二小臼歯の歯根形成開始を待って対応した方が良いと考えられた。, The aims of this retrospective study were to examine the eruption disturbances of the mandibular second premolar caused by abnormal inclination of the tooth germs and to discuss and demonstrate the recommended treatment for these cases. The subjects comprised of 11 patients (eight girls and three boys) in whom the eruption of 15 mandibular second premolars was disturbed by aberrant direction of the tooth germs. The patients were treated at the Pediatric Dental Clinic of Niigata University Medical and Dental Hospital during 28 years from September 1979 to January 2008. The ages of the patients at the time of diagnosis ranged from 8 years exactly to 13 years and 11 months. The eruption disturbance occurred unilaterally in seven cases (five on the right side and two on the left) and bilaterally in four cases. In 14 of 15 affected premolars, the tooth germs exhibited distal inclinations. A strong correlation between the degree of distal inclination and the delay in formation of the tooth germ was observed (correlation coefficient: R>0.70); the more significant the delay in formation of the tooth germ, the higher the degree of distal inclination. In unilateral cases, the tilting degree was very high, and the formation of the tooth germ was significantly delayed. In bilateral cases, however, both the tilting degree and delay in formation were not severe, and were almost the same on both sides. A comparison between the unilateral group and the bilateral one revealed that the degree of distal inclination was considerably higher in the unilateral group (P<0.01). In the cases of 14 teeth among 10 patients (all but one unilateral case, in which血e patient was very young), the primary second molars were removed soon after diagnosis. The cases that had serious tilting, however, showed only slight improvement of the aberrant tilting even after their predecessors were extracted early, and additional complex treatments such as bone fenestration or traction of the affected tooth were

This is a clinical and radiographic review of 87 hips in 79 patients 9 (7-11) years after acetabular revision with extensive use of morselized allograft firmly impacted into localized defects as well as the entire acetabular cavity, followed by insertion of an uncemented hydroxyapatite-coated cup with supplementary screw fixation. The 9-year survival rate for the acetabular implant was 90.5% (95% CI, 83.4%-97.6%) with revision for any reason as end point and 94% (95% CI, 89%-99.1%) with revision for aseptic loosening as end point. Acetabular revision with massive allograft impaction and hydroxyapatite-coated implants show very promising results. The limited contact between implant and host bone does not seem to compromise implant survival in the 7- to 11-year perspective.

当科外来で経験した上顎犬歯埋伏の5症例について報告し,その原因と,発見及び処置方法について若干の考察を行った｡症例は8歳6か月から11歳8か月までの5例で,左側埋伏が2例,右側2例,両側性が1例であった｡他院より紹介され,埋伏を主訴に来院したものが2例,齲蝕,不正咬合の治療で当科に通院中にⅩ線写真を撮影し,犬歯の萌出方向の異常を認めたものが3例であった｡また,発見時に先行乳犬歯が残存していたものが4例であった｡全症例においてⅩ線写真上で埋伏犬歯の近心傾斜が認められ,近心傾斜程度の低い1例を除き,4例は歯冠を口蓋側に向けて埋伏していた｡年齢が低く,近心傾斜の小さい症例では乳犬歯を抜歯して萌出余地を確保することで改善した｡逆に,年齢が高く,近心傾斜の大きい症例では開窓し,牽引した｡埋伏位置が最も重度であった1例は,その後摘出に至った｡埋伏原因として萌出余地不足,側切歯部に存在した奇形歯による萌出障害,乳犬歯の根尖病巣,あるいは顎骨内での犬歯歯胚の位置異常などが考えられた｡埋伏の発見については,年齢,乳犬歯の残存状態,健側犬歯の萌出程度を考慮し,早期発見することが重要であり,萌出開始時期に頬側歯肉に歯冠の膨隆を触知するかどうかを確認することが必要であると考えられた｡また,処置方法とその予後は,犬歯歯冠の位置,歯根形成状態により左右されると思われた｡

Bakalářská práce se zabývá účinností depozice vláknových částic prostřednictvím různých mechanismů depozice. Podrobněji rozebírá účinnost depozice pomocí difuze, sedimentace a impaktu. Uvádí implementaci Peterlinova analytického řešení pro výpočet ODF, které je využíváno pro řešení daných účinností. Dále jsou v ní obsaženy vzorce pro výpočet jednotlivých účinností odvozených pro sférické částice a přepočet příslušných parametrů pro vlákna. Cílem práce je vymodelování grafů, které znázorňují závislost účinností jednotlivých depozic na velikosti poměru délky a průměru vláken. Dalším úkolem této práce je vytvoření grafů, které zobrazují srovnání různých režimů dýchání pro dané mechanismy depozice. Vše je počítáno a vykreslováno v prostředí programu MATLAB., The Bachelor's thesis deals with a deposition efficiency for a fibers by various mechanisms of a deposition. It explains deposition efficiency by diffusion, by sedimentation and by impaction. The implementation of Peterlin's analytical solution for calculation of the ODF, which is used for individual efficiencies solution, is also mentioned. Afterwards, the thesis summarizes formulas for calculation of particular efficiencies derived for spherical particles and recomputation appropriate parameters for fibers. The purpose of the thesis is to create graphs, which illustrate deposition efficiencies dependence by various mechanisms on the aspect ratio of fibers. Another goal is the graphs creation, which shows juxtaposition for various breathing modes for given deposition mechanisms. The software MATLAB is used for the whole calculation process and graphs plotting.

Bakalářská práce se zabývá účinností depozice vláknových částic prostřednictvím různých mechanismů depozice. Podrobněji rozebírá účinnost depozice pomocí difuze, sedimentace a impaktu. Uvádí implementaci Peterlinova analytického řešení pro výpočet ODF, které je využíváno pro řešení daných účinností. Dále jsou v ní obsaženy vzorce pro výpočet jednotlivých účinností odvozených pro sférické částice a přepočet příslušných parametrů pro vlákna. Cílem práce je vymodelování grafů, které znázorňují závislost účinností jednotlivých depozic na velikosti poměru délky a průměru vláken. Dalším úkolem této práce je vytvoření grafů, které zobrazují srovnání různých režimů dýchání pro dané mechanismy depozice. Vše je počítáno a vykreslováno v prostředí programu MATLAB., The Bachelor's thesis deals with a deposition efficiency for a fibers by various mechanisms of a deposition. It explains deposition efficiency by diffusion, by sedimentation and by impaction. The implementation of Peterlin's analytical solution for calculation of the ODF, which is used for individual efficiencies solution, is also mentioned. Afterwards, the thesis summarizes formulas for calculation of particular efficiencies derived for spherical particles and recomputation appropriate parameters for fibers. The purpose of the thesis is to create graphs, which illustrate deposition efficiencies dependence by various mechanisms on the aspect ratio of fibers. Another goal is the graphs creation, which shows juxtaposition for various breathing modes for given deposition mechanisms. The software MATLAB is used for the whole calculation process and graphs plotting.

Tato bakalářská práce se zabývá problematikou separace jemných částic metodou impakce. V úvodu práce jsou představeny hlavní polutanty ovzduší, přičemž blíže je pohled zaměřen na tuhé znečišťující látky. U tohoto typu znečištění jsou uvedeny vlastnosti, principy vzniku a také legislativa a vliv na lidské zdraví. Následně jsou popsány možné metody laboratorního záchytu tuhých látek, přičemž detailně je popsána metoda impakce. Praktická část práce je zaměřena na výpočet hlavních rozměrů, konstrukci a výrobu virtuálního impaktoru. Byly vyrobeny virtuální impaktory pro separaci částic PM2,5 a PM10 v několika konstrukčních a materiálových provedeních. V závěru bylo uskutečněno měření ověřující funkčnost navržených zařízení s ohledem na účinnost separace., This bachelor thesis follows up fine particle separation issue with use of impaction method. The introduction is focused on main air pollutants. Closely the solid pollutants and their properties such as formation principle, legislation and human health impact are showed. Following parts describes methods of fine particle capture and closer is focused on impaction method. In the experimental part of this thesis main dimension calculation, construction and manufacturing process of virtual impactor is presented. Several construction and material types of virtual impactor has been fabricated. Finally, a separation efficiency measurement was made. This measurement confirms properties of PM2,5 and PM10 virtual impactor.

Tato bakalářská práce se zabývá problematikou separace jemných částic metodou impakce. V úvodu práce jsou představeny hlavní polutanty ovzduší, přičemž blíže je pohled zaměřen na tuhé znečišťující látky. U tohoto typu znečištění jsou uvedeny vlastnosti, principy vzniku a také legislativa a vliv na lidské zdraví. Následně jsou popsány možné metody laboratorního záchytu tuhých látek, přičemž detailně je popsána metoda impakce. Praktická část práce je zaměřena na výpočet hlavních rozměrů, konstrukci a výrobu virtuálního impaktoru. Byly vyrobeny virtuální impaktory pro separaci částic PM2,5 a PM10 v několika konstrukčních a materiálových provedeních. V závěru bylo uskutečněno měření ověřující funkčnost navržených zařízení s ohledem na účinnost separace., This bachelor thesis follows up fine particle separation issue with use of impaction method. The introduction is focused on main air pollutants. Closely the solid pollutants and their properties such as formation principle, legislation and human health impact are showed. Following parts describes methods of fine particle capture and closer is focused on impaction method. In the experimental part of this thesis main dimension calculation, construction and manufacturing process of virtual impactor is presented. Several construction and material types of virtual impactor has been fabricated. Finally, a separation efficiency measurement was made. This measurement confirms properties of PM2,5 and PM10 virtual impactor.

Bakalářská práce se zabývá účinností depozice vláknových částic prostřednictvím různých mechanismů depozice. Podrobněji rozebírá účinnost depozice pomocí difuze, sedimentace a impaktu. Uvádí implementaci Peterlinova analytického řešení pro výpočet ODF, které je využíváno pro řešení daných účinností. Dále jsou v ní obsaženy vzorce pro výpočet jednotlivých účinností odvozených pro sférické částice a přepočet příslušných parametrů pro vlákna. Cílem práce je vymodelování grafů, které znázorňují závislost účinností jednotlivých depozic na velikosti poměru délky a průměru vláken. Dalším úkolem této práce je vytvoření grafů, které zobrazují srovnání různých režimů dýchání pro dané mechanismy depozice. Vše je počítáno a vykreslováno v prostředí programu MATLAB., The Bachelor's thesis deals with a deposition efficiency for a fibers by various mechanisms of a deposition. It explains deposition efficiency by diffusion, by sedimentation and by impaction. The implementation of Peterlin's analytical solution for calculation of the ODF, which is used for individual efficiencies solution, is also mentioned. Afterwards, the thesis summarizes formulas for calculation of particular efficiencies derived for spherical particles and recomputation appropriate parameters for fibers. The purpose of the thesis is to create graphs, which illustrate deposition efficiencies dependence by various mechanisms on the aspect ratio of fibers. Another goal is the graphs creation, which shows juxtaposition for various breathing modes for given deposition mechanisms. The software MATLAB is used for the whole calculation process and graphs plotting.

Tato bakalářská práce se zabývá problematikou separace jemných částic metodou impakce. V úvodu práce jsou představeny hlavní polutanty ovzduší, přičemž blíže je pohled zaměřen na tuhé znečišťující látky. U tohoto typu znečištění jsou uvedeny vlastnosti, principy vzniku a také legislativa a vliv na lidské zdraví. Následně jsou popsány možné metody laboratorního záchytu tuhých látek, přičemž detailně je popsána metoda impakce. Praktická část práce je zaměřena na výpočet hlavních rozměrů, konstrukci a výrobu virtuálního impaktoru. Byly vyrobeny virtuální impaktory pro separaci částic PM2,5 a PM10 v několika konstrukčních a materiálových provedeních. V závěru bylo uskutečněno měření ověřující funkčnost navržených zařízení s ohledem na účinnost separace., This bachelor thesis follows up fine particle separation issue with use of impaction method. The introduction is focused on main air pollutants. Closely the solid pollutants and their properties such as formation principle, legislation and human health impact are showed. Following parts describes methods of fine particle capture and closer is focused on impaction method. In the experimental part of this thesis main dimension calculation, construction and manufacturing process of virtual impactor is presented. Several construction and material types of virtual impactor has been fabricated. Finally, a separation efficiency measurement was made. This measurement confirms properties of PM2,5 and PM10 virtual impactor.

Bakalářská práce se zabývá účinností depozice vláknových částic prostřednictvím různých mechanismů depozice. Podrobněji rozebírá účinnost depozice pomocí difuze, sedimentace a impaktu. Uvádí implementaci Peterlinova analytického řešení pro výpočet ODF, které je využíváno pro řešení daných účinností. Dále jsou v ní obsaženy vzorce pro výpočet jednotlivých účinností odvozených pro sférické částice a přepočet příslušných parametrů pro vlákna. Cílem práce je vymodelování grafů, které znázorňují závislost účinností jednotlivých depozic na velikosti poměru délky a průměru vláken. Dalším úkolem této práce je vytvoření grafů, které zobrazují srovnání různých režimů dýchání pro dané mechanismy depozice. Vše je počítáno a vykreslováno v prostředí programu MATLAB., The Bachelor's thesis deals with a deposition efficiency for a fibers by various mechanisms of a deposition. It explains deposition efficiency by diffusion, by sedimentation and by impaction. The implementation of Peterlin's analytical solution for calculation of the ODF, which is used for individual efficiencies solution, is also mentioned. Afterwards, the thesis summarizes formulas for calculation of particular efficiencies derived for spherical particles and recomputation appropriate parameters for fibers. The purpose of the thesis is to create graphs, which illustrate deposition efficiencies dependence by various mechanisms on the aspect ratio of fibers. Another goal is the graphs creation, which shows juxtaposition for various breathing modes for given deposition mechanisms. The software MATLAB is used for the whole calculation process and graphs plotting.

Tato diplomová práce je zaměřená na problematiku laboratorního záchytu jemných částic me-todou impakce. Úvodní kapitola je věnována rešerši jemných částic v ovzduší a vlivu znečištění ovzduší na člověka a na životní prostředí. Druhá kapitola slouží k obeznámení s historií im-pakčních zařízení, popisu principu kaskádového impaktoru a teorie záchytu jemných částic změnou směru proudu vzduchu unášejícího částice a jejich zachycení při nárazu na pevnou stěnu. V praktické části diplomové práce je zpracován výpočtový postup pomocí programova-cího jazyka Python pro vlastní návrh vícestupňového impaktoru. Parametry získané z vytvoře-ného výpočtového softwaru jsou porovnány s parametry komerčního impaktoru, dostupného na fakultě školy. Podle zpracovaného výpočtového postupu je navržen vlastní vícestupňový im-paktor pro separaci částic v rozsahu od PM0,5 do PM0,1., This master’s thesis is focused on the problem of laboratory capture of fine particles by the impaction method. The introductory chapter is devoted to the investigation of fine particles in air and the impact of air pollution on humans and the environment. The second chapter intro-duces the history of impaction devices, describes the principles of the cascade impactor, and explains the theory behind fine particle capture by changing the direction of the airflow carrying the particles and their capture when they hit a solid wall. In the practical part of the thesis, a computational procedure is developed using the Python programming language for a custom design of a multi-stage impactor. The parameters obtained from the developed computational software are compared with those of a commercial impactor available at the faculty of the school. According to the developed computational procedure, a custom multi-stage impactor is designed for particle separation in the range of PM0.5 to PM0.1.