Cavity Area Research Articles

Enhancing neuroprotective effect of aminosalicylic acid-grafted chitosan electrospun fibers for spinal cord injury.

The hyperinflammation microenvironment after spinal cord injury (SCI) remains a great challenge for neural regeneration. Methylprednisolone has been used to reduce the inflammatory response after SCI, but it is controversial due to side effects associated with off-specific targeting effects. In this study, we synthesized in situ 5-ASA grafted chitosan electrospun fibers (ASA-EF) with excellent injectable and self-healing properties to reprogram nerve cells via displaying biological distribution, gene expression, and functional changes. With the support of ASA-EF, the downregulation of inflammatory cytokines expression and the upregulation of anti-inflammatory and regenerative gene expression were found in vitro studies. Moreover, ASA-EF administration polarized macrophages toward proregenerative phenotypes in the injured lesion, and significantly reduced cavity area. In addition, ASA-EF administration increased myelination and regenerating axons and improved motor function (score of 5 versus 2 for SCI group). These results illustrate that the neuroprotective effect of this artificial nanoplatform will facilitate the clinical treatment of traumatic-related diseases via forming a recycled microenvironment that supports regeneration and functional recovery. These particles may be applied to trauma and potential other inflammatory diseases.

Dual gate AlGaN/GaN MOS-HEMT biosensor for electrical detection of biomolecules-analytical model

This paper proposes an analytical model for a dual gate AlGaN/GaN Metal oxide semiconductor-high-electron-mobility transistor (MOS-HEMT) biosensor for electrical detection of neutral species such as Biotin, Keratin, ChOx, and Zein. When only one subband is occupied and the AlGaN layer is assumed to have been fully ionized, the Fermi–Dirac statistic and 2D state density are used to produce a self-consistent calculation of the carrier density in the quantum well at the interface. It is done by analyzing the impact of biomolecule concentration by inserting a biomolecule of appropriate dielectric permittivity in the cavity area beneath the gate region. The impact of cavity length has been analyzed on the sensor’s performance. The proposed device significantly changes the channel potential, transconductance, drain current, and threshold voltage. Dual gate structures offer superior resistance to short channel effects. Due to enhanced transport characteristics, high carrier mobility, drain current, and a variety of other factors, double gate MOS HEMT outperforms single-gate MOS HEMT. The maximal transconductance, drain on sensitivity, and the maximal drain current that has been attained in this work is 0.017 s, 0.22 and 0.129 mA, respectively, for biomolecule concentration, N b = 3 × 1012. Among all the biomolecules used in this study, Keratin has achieved the maximum shift in threshold voltage and transconductance of 0.4 V and 0.016 s. The increase in current for Keratin, Biotin, Zein, and ChOx is 0.67%, 78%, 17%, and 42%, respectively, from single to dual gate AlGaN/GaN MOS-HEMT. SiO2, Al2O3, and HfO2 oxides have been compared by filling them in the left side of the cavity. Dual gate AlGaN/GaN MOS-HEMT biosensor presents an opportunity to develop robust, low-cost, specific detection and analysis of neutral biomolecule. The analytical model provides good results for drain current according to the comparison of simulation and analytical model findings.

Placement of Plastic Stents after Direct Endoscopic Necrosectomy through a Novel Lumen-Apposing Metal Stent for Effective Treatment of Laterally Extended Walled-Off Necrosis: A Pilot Study.

Direct endoscopic necrosectomy (DEN) using a lumen-apposing metal stent (LAMS) is a standard therapy for the management of symptomatic walled-off necrosis (WON). Here, we demonstrated the efficacy of the routine placement of long plastic stents after a DEN session to treat laterally extended WON. Patients (n = 6) with symptomatic laterally extended WON who underwent DEN after long plastic stent placement were included. The primary endpoint was clinical efficacy of the procedure. The technical and clinical success rates were 100% without major adverse events. The WON extended to the pelvic cavity or pericolic area, and the WON size was between 18.6 and 35.8 cm in length. The median number of DEN sessions was 10 (range 6-16), and two or three long plastic stents were placed after every DEN session. Only one patient suffered from pneumoperitoneum during DEN, which spontaneously resolved within 20 min. Placement of a long plastic stent after DEN using LAMS is a minimally invasive and effective treatment for symptomatic laterally extended WON. Further studies are needed to define the indications and most suitable patients.

Clinical effect of standardized nursing for lymphoma patients and the influencing factors of nosocomial infection.

To analyze the clinical effect of standardized nursing for lymphoma patients and the influencing factors of nosocomial infection, a total of 360 diffuse large B-cell lymphoma patients with disease recurrence or progression after first-line treatment were retrospectively selected from our hospital from January 2021 to July 2022. After standardized nursing, the overall infection rate of lymphoma patients was 2.50% (9/360), which was significantly lower than the overall infection rate of our hospital in 2021 (7.44%, 844/11342) (P < .05). The proportion of 3 kinds of pathogenic bacteria detected were G+ bacteria (33.5%), G- bacteria (53.3%), and fungi (13.2%). The pathogenic bacteria genus with the most G+ bacteria is Enterococcus, the pathogenic bacteria genus with the most G+ bacteria is Enterobacteriaceae, and the pathogenic bacteria with the most fungi is Candida albicans. Female infection rate was significantly higher than male (P < .05). There was no significant difference in nosocomial infection among different marital status/fertility status (P > .05). The nosocomial infection of patients with different hospitalization times was statistically significant (P < .05). The duration of hospitalization in the infected group was significantly higher than that in the non-infected group (P < .05). The clinical effect of standardized nursing for lymphoma patients is significant, and the influencing factors of nosocomial infection include patient gender, hospitalization frequency, and hospitalization duration.

Epigenetic methylation changes: implication as biomarkers in oral and maxillofacial area cancers.

Squamous cell carcinoma (SCC) is the most frequent cancer of the head and neck area in the oral cavity. Epigenetic alterations in oral and maxillofacial area cancers are urgently needed to be investigated, as the observed changes might have crucial diagnostic value for personalized medicine. Our study aimed to identify the most frequently hypermethylated tumor suppressor gene promoters in OSCC, followed by correlation analysis with the patients' survival. We evaluated the methylation status of the promoters in a panel of 22 tumor suppressor genes in Romanian (n=9) and Bulgarian (n=12) patient groups suffering from oral and maxillofacial area cancers. The extracted DNA was further digested through EpiTect Methyl II PCR Array System containing methylation-sensitive and methylation-dependent restriction enzymes, followed by specific amplification of the products obtained by qPCR and data analysis using the online platform provided by the producer. Different methylation patterns were observed in the tumor suppressor genes' promoters. Among them, the methylation profile of Cccnd2, Chd1, Cdh13, Cdkn1c, Neurog1, Gstp1, and Runx3 genes further correlated with overall survival rates. Our data emphasize that epigenetic alterations are responsible for the clinical heterogeneity of oral and maxillofacial area cancers and significantly impact on patient survival. Additional investigation on a larger patient cohort should validate these potential biomarkers.

Experimental investigation of two-phase flow evolution in a high-speed submerged water jet with air ventilation

In order to improve the submerged cutting performance of water abrasive suspension jet an experimental investigation on the two-phase flow structure of submerged water jet with semi-coaxial air ventilation is conducted by the method of high-speed camera observation under the condition of flow dynamic similarity, and its unsteady behavior under different conditions is evaluated by analyzing of sequence images. Experiment results show that the flow pattern of air-ventilated jet depends upon the ventilation flow rate. It may be classified into bubbly flow surrounded jet, continuous air-layer covered jet and cavity-bubble flow surrounded jet. In the case of non-ventilation, high-speed water jet into water is accompanied by intensive cavitation and the flow field appears to be a narrow jet surrounded by cavitation bubble clouds. By ventilating to the cavitating jet, air-bubbles become bigger gradually and a cavity area is formed at the exit of nozzle head. When the ventilation flow ratio reaches to the level of 5 a large cavity covering the jet is formed and a continuous air-layer covered jet is then generated. Image analysis demonstrates that the continuous air-layer covering the liquid jet pulsates and sheds downstream periodically. The Strouhal number defined by the dominant frequency of jet pulsation decreases quickly with the increase of ventilation flow rate in the range of Cq ≤ 5. At a suitable ventilation flow ratio (Cq ≈ 6 ~ 8) a relative long stable continuous air-layer covering the jet is generated at high time ratio, which will dramatically enhance the processing ability of submerged water jets. Cutting tests demonstrates that the cutting ability of air ventilated jet depends on the ventilation flow ratio. The relation of processing ability with the flow structure of air ventilated jet is clarified.

HPV-associated pathology of the oral mucosa and anogenital area. (Rationale for combined therapy)

Was to evaluate the effectiveness and duration without a relapse period in patients with HPV-associated pathology of the oral mucosa and in combination with lesions of the anogenital region during combined therapy, including destruction and Panavir. The study included 60 women diagnosed with «Viral warts. Genital condyloma of the oral cavity. 15 patients were also diagnosed with «Anogenital warts». The patients were divided into three groups of 20 women (15 with HPV-associated pathology of the oral cavity; 5 with combined HPV-associated pathology of the oral cavity and anogenital area). In the first group, the drug Panavir was administered intravenously. Between the third and fourth injections radiosurgical destruction of condylomas was carried out followed by Panavir gel applications until complete epithelialization of the destruction zone and further use of Panavir-inlight spray in the oral cavity and Panavir-intim spray in the anogenital area for 4 weeks. In the second group, the destruction of genital warts was carried out only with local treatment identical to that in the first group. In the third group after destruction applications of an oil solution of vitamin A were added to the oral mucosa 3-4 times a day until complete epithelization of the lesion, an alcohol solution of fucorcin and panthenol cream were applied externally in the anogenital area. According to clinical and laboratory monitoring after 3, 6 and 12 months, HPV elimination in the first group was achieved in 70, 85 and 90% of cases; in the second group in 50, 75 and 80%; in the third group in 30, 40 and 40%, respectively; within 12 months, relapses in the first group were registered in 10% of cases; in the second and third groups in 20% and 45% of cases, respectively. Combined therapy including destruction and complex use of different dosage forms of the drug Panavir showed higher clinical efficacy and allowed to achieve a reduction in the rate of condyloma relapses.

Bilateral sialocele associated with osseous metaplasia in a dog

Sialocele is a lesion characterized by a cavity filled with saliva and delimited by granulation tissue and is the most commonly observed condition in dogs' salivary glands. A cervical swelling was observed in a male, mixed breed, 12-year-old dog. When punctured, the local was filled with saliva. The animal was referred for sialoadenectomy, and bilateral involvement was observed, with stony material delimiting the sialoceles on both sides. Samples were sent for histopathological examination, which showed cavity areas without epithelial delimitation, with osseous metaplasia and chronic inflammation. Such characteristics allowed the diagnosis of bilateral sialocele associated with osseous metaplasia. The presence of osseous metaplasia in sialoceles is extremely rare, with only four other cases described, which makes it difficult to reach conclusions related to epidemiology and pathogenesis.

Mixed Convective Heat Transfer Analysis by Heatlines on a Lid‐Driven Cavity Having Heated Wavy Wall Containing Tilted Square Obstacle

The current problem studies the mixed convective heat transport by heatlines in lid‐driven cavity having wavy heated walls with two diamond‐shaped obstacles. The left and right vertical walls are both cold, whereas the top wall is adiabatic, and the bottom wavy wall is heated. The relevant governing equation has been calculated through using the finite element method as well as the Galerkin weighted residual approach. The implications of the Reynolds number (10 ≤ Re ≤ 500), Richardson number (0.01 ≤ Ri ≤ 10), Hartman number (0 ≤ Ha ≤ 100), Prandtl number (0.015 ≤ Pr ≤ 10), Undulations number (1 ≤ N ≤ 4), and inner diamond shape obstacle are depicted by the streamlines, isotherms, and the heatlines. The convection heat transfer is observed to be fully developed at a high Prandtl number, whereas heat conduction happens at poor Pr. In particular, the undulations number has the greatest effect on the streamlines and isotherm contrast to a flat area. The Nusselt numbers increase as the Reynolds and Prandtl numbers rise as well. The isotherm, streamlines, heatlines, Nusselt number, and fluid flow are shown graphically for several relevant dimensionless parameters. The result demonstrates that a single oscillation of a heated wall with such a poor Richardson number is optimal heat transport in the cavity. The presence of undulations minimizes the cavity area; the case N = 3 makes quicker fluid motions and better heat transfer in the present research. Additionally, the interior obstacle size reduces the amount of space it takes up within the wavy cavity, and it was observed that the obstacle with diamond size D = 0.15 is better than that with any other size.

Evaluation of olfactory threshold changes in patients treated with rapid maxillary expansion

Aim: Rapid maxillary expansion (RME) provides an orthopedic effect that solves the problem of transverse deficiency of the maxilla. Moreover, it contributes positively to the functioning of the entire nasopharynx by increasing the cross-sectional area and volume of the nasal tract, thus reducing airway resistance. The aim of this study was to evaluate the changes in olfactory threshold after RME treatment of patients with maxillary transverse deficiency. Methodology: Olfactory threshold and identification tests as well as acoustic rhinometry parameter (Volume1, MCA1, Volume2, MCA2) measurements were conducted for 40 patients (11–16 years) before treatment (T0) and 6 months after (T1) rapid maxillary expansion application. Results: A significant improvement was observed when the olfactory threshold values at T0 (0.96 ± 0.07) and T1 (0.79 ± 0.13) (p &lt; 0.001) were compared. A significant improvement was also observed upon comparing the identification test results at T0 (0.63 ± 0.13) and T1 (0.79 ± 0.11) (p &lt; 0.001). The acoustic rhinometry results showed a significant increase in Volume 1, MCA1, Volume 2 and MCA2 in the right and left nasal cavities after treatment (p &lt; 0.001). Conclusion: In this study, acoustic rhinometry showed that nasal cavity area and volume increased in patients who underwent rapid maxillary expansion therapy. Further, the olfactory functions measured by the olfactory threshold test and identification test improved significantly. How to cite this article: Yıldırım M, Erdur EA, Erdur Ö, Metli ŞN. Evaluation of olfactory threshold changes in patients treated with rapid maxillary expansion. Int Dent Res 2022;12(Suppl.1):90-6. https://doi.org/10.5577/intdentres.435 Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

Design and Analysis of Charge Plasma-Based Vertical-Nanowire Tunnel FET for Biosensor

In the semiconductor industry, nanoscale devices have better ability to provide for biomolecules detection, but they face various problems during fabrication process, such as high doping concentration, random dopant fluctuation (RDF), higher production cost, low electrostatic control. To overcome these problems, charge plasma (CP) technique has been introduced by the formation of hafnium material at drain side and platinum material at source side with appropriate work-function. The proposed work charge plasma-based vertical-nanowire tunnel FET (CP-VNWTFET) has been designed and analyzed for biosensor application using different dielectric constant and gate underlap method by creating a cavity area under the gate metal. The sensitivity ([Formula: see text]) of biosensor is calculated in terms of change in drain-current ([Formula: see text]) and transconductance ([Formula: see text]) by immobilizing the biomolecules such as Urease, Keratin, Streptavidin, ChOX, Zein, Gluten using gate underlap and dielectric modulation technique. The performance parameters like subthreshold slope (SS), off-current ([Formula: see text]), on-current ([Formula: see text]), on/off current ratio ([Formula: see text]) of the CP-VNWTFET have also been observed while varying the neutral and charged biomolecules at various biased conditions. The device is simulated by using Silvaco ATLAS simulator. The proposed device has been found to be suitable for low power sensor design application.

Enhancing the Photocatalytic Degradation Efficiency of Dyes of Copper-Based Metal-Organic Frameworks through a Dimension-Induced Structural Strategy.

Photocatalytic degradation of pollutants is an effective environment purification strategy. Metal-organic frameworks (MOFs) have attracted extensive attention in the field of photocatalysis owing to their structural diversity, uniform cavity, and large specific surface area. However, poor electrical conductivity, light absorption, and water stability restrict their development. The tailorable structure of MOFs may effectively overcome these limitations. Herein, three Cu-based MOFs (complexes 1-3) with one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D) structures, respectively, were successfully prepared by introducing different uncoordinated ligands and adjusting the ligand/metal salt ratio. Among them, complex 1 with a 1D chain was constructed as a typical J-type aggregation by π-π stacking interactions between adjacent naphthalene rings. This intermolecular aggregation mode enhances strong exciton coupling between conjugated rings, reduces the transition energy, expands the intrinsic light absorption edge, and provides a channel for electron transport, thus improving the charge-separation efficiency. As expected, complex 1 with a 1D chain structure exhibited excellent Fenton-like catalytic activity. The apparent reaction rates were 3.2 and 2.0 times higher than those of 2D and 3D MOFs, respectively.

Influence of Tip Clearance on Cavitation Characteristics of an Inducer of Turbopump: CFD Study

The tip clearance, a compact gap between the inducer blade tip and casing wall, is critical to both the liquid leakage and cavitation-induced forces of a turbopump. In this study, we numerically investigate the effect of tip clearance on the cavitation characteristics of an inducer. Six different tip clearances, 0.1, 0.3, 0.5, 1.0, 1.5, and 2 mm, namely Models A–F, were designed to evaluate the cavitation performance, cavity structure, blade loading, radial force, etc. Model D (1.0 mm) had the relatively highest head coefficient and smallest cavity area on each blade as compared to all other models. The pressure coefficient distribution and blade loading further confirmed that Model D can maintain a higher pressure head and better suppress the cavitation onset than the other models. The radial force signals in the time and frequency domains show that Model D has an intermediate force magnitude with slightly higher noises at the rotating frequency and its harmonic frequencies. Model D also has a relatively smaller vortex region and smaller vortex strength (λ2 criterion). In short, all results show that Model D is the best alternative to balance the complex interactions of the bulk flow and tip leakage flow, compromising the hydraulic head and rotating cavitation.

A triple point of water cell-based fixed-point blackbody for radiation thermometry

The radiation temperature metrology above 150 °C relies heavily on the use of physical interpolation equations and known reference temperature (provided by solid–liquid phase transition of high-purity metals and metal-carbon eutectic alloys) fixed-point blackbodies. Recent achievements in thermal infrared detector technologies triggered the extension of the scale interpolation below this temperature down to 0 °C by using the reference temperatures provided by Sn, In, Ga fixed-points and ice-point, where the reference temperature of the later is dependent on external parameters. In this work, we demonstrate that the triple-point of water (TPW) based fixed-point blackbody is the metrologically grounded alternative to the ice-point. For this purpose, a fixed-point blackbody, incorporating only a cavity and large area TPW (LATPW) cell was designed, constructed, and validated for the precise calibration of radiation thermometers (RTs) and thermal cameras at the thermodynamic temperature of TPW. The conceptual design of the LATPW cells is similar to the ones used in contact thermometry, where a thermometer well of the cell is employed as a borehole for a cavity, where the cavity is easily detachable. Four different cavities (two different designs with aperture sizes of 40 mm and 50 mm) and three LATPW cells with two distinct well geometries were comparatively studied in several combinations. The largest absolute temperature difference observed between the primary level reference TPW cell (used in contact thermometry) and the LATPW cells is measured to be only 0.37 mK. Radiometric measurements demonstrate that all radiators maximally reflect the blackbody condition including emissivity close to unity, high uniformity across the aperture and high temporal stability. The simplicity of maintenance and easy in-field usage (only distilled water and dry ice are required) make the TPW blackbodies very versatile for the in-situ calibrations of RTs and thermal cameras, allowing its application in many areas including clinical environments.

Mechanical Behavior of Composite Filled Teeth Under Compression Load

Bu çalışmada, basma yüküne maruz bırakılmış üç farklı kavite alanına sahip kompozit restorasyonlu sağ üst premolar dişte meydana gelen eş değer (von Mises) gerilmeleri ve toplam deformasyon değerleri incelenmiştir. Model sonlu elemanlar yöntemine göre temellendirilmiş olup ANSYS Workbench paket programı kullanılarak analizler gerçekleştirilmiştir. Çalışma sonucunda çiğneme kuvveti uygulanan dişlerde gerilme değerlerinin üç farklı kaviteye sahip dişlerde yakın değerler olduğu ve dişlerde kalıcı hasarın meydana gelmediği saptanmıştır. Dişlerde oluşan gerilmenin kuvvetin uygulandığı tepelerde ve kuron ile kökün birleşim bölgesinde yoğunlaştığı gözlemlenmiştir. Kavitenin açıldığı bölgenin dişte oluşacak olan gerilme ve deformasyonu etkilediği tespit edilmiştir.

Odontogenic Abscesses during the Pandemic by SARS-CoV-2

Dental abscess are pathologies caused by infectious processes in the teeth and/or their surrounding tissues. They can lead to complications, or in some cases they can be lethal, in base of the anatomy of the area of the oral cavity in which they develop. Therefore, this is a recurrent reason why patients with an odontogenic abscess may need to go to the dental emergency room. In this study, the access data to the emergency room of the “Policlinico Umberto I” of patients with odontogenic abscesses were analyzed and were put into a relation with the epidemic by SARS-CoV-2. The periods of 2019 and 2020 have been taken into consideration and the pre- and post- lockdown periods were analyzed by comparing the data. Due to the restrictions imposed during the lockdown in Italy, we would have expected an increase in the number of accesses to the dental emergency room for odontogenic abscesses, but the results showed a decrease in the percentage of accesses for this pathology. Having regard to the results, an attempt to give a logical explanation to this decline in the numbers recorded at our Polyclinic has been made.

Human Monkeypox: Oral Implications and Recommendations for Oral Screening and Infection Control in Dental Practice.

The World Health Organization declared the spread of the human monkeypox virus (MPXV) an "emerging threat of moderate health concern" on 23 June 2022. Although about 20,000 cases of Monkeypox (MPX) were recorded in Europe and more than 28,000 in the United States from May to October 2022, their number is still small compared to the number of dental patients treated annually. Therefore, the likelihood of oral healthcare workers encountering an MPX case is relatively low in not endemic regions. In addition, MPX-positive individuals are considered contagious only during the prodromal or acute phase. However, the exact shedding and transmission routes of MPX and the associated risk of transmission in the dental setting remain unclear. Moreover, infected subjects whose disease is confined to the head and neck may require oral and dental care because they complain of lymphadenopathy involving the cervical lymph nodes. Furthermore, MPX lesions may first appear in the oral cavity or perioral area. Therefore, given the recent spread of MPXV in non-endemic areas where dentists are not used to considering this disease in the differential diagnosis and taking appropriate preventive measures, all oral healthcare providers nowadays should be aware of the oral presentation of MPX for adequate oral screening and appropriate preventive measures for infection control in the dental practice.

Diagnosis of yeasts isolated from the oral cavity and groin area in children of Kirkuk city/Iraq

This study was conducted in the Graduate Studies Laboratory / College of Education for Pure Sciences - Kirkuk University; 200 swabs were collected from the oral and groin areas of children infected with candidiasis for both inpatients and outpatients at the Children’s Hospital, the Maternity, Gynecology and Children’s Hospital, and Azadi Teaching Hospital in Kirkuk governorate; whose ages ranged from 1 day - 3 years for both males and females; For a period ranging from February-2021 to March 25-2021. The immediate results of the microscopic examination showed that 152 smears (76%) were positive, while the results of culturing the smears on solid Sabouraud medium showed that 140 smears (70%) of the smears showed growth, and 60 smears (30%) of the smears showed no growth.&#x0D; Five species belonging to the genus Candida were identified by biochemical tests and culture on Chrome Agar Candida medium. Led by the yeast Candida albicans with 74 isolates and (52.85%), followed by Candida tropicalis with 34 isolates and (24.28%), then Candida lusitaniae 13 isolates with a percentage of (9.28%), then Candida krusei with 11 isolates and (7.85%), while Candida glabrata recorded 8 isolates with a percentage of (5.71%).

Occurrence of antimicrobial resistance and antimicrobial resistance genes in methicillin-resistant Staphylococcus aureus isolated from healthy rabbits.

Methicillin-resistant globally, Staphylococcus aureus (MRSA) is a major cause of disease in both humans and animals. Several studies have documented the presence of MRSA in healthy and infected animals. However, there is less information on MRSA occurrence in exotic pets, especially healthy rabbits. This study aimed to look into the antimicrobial resistance profile, hidden antimicrobial-resistant genes in isolated bacteria, and to estimate prevalence of MRSA in healthy rabbits. Two-hundreds and eighteen samples, including 42 eyes, 44 ears, 44 oral, 44 ventral thoracic, and 44 perineal swabs, were taken from 44 healthy rabbits that visited the Prasu-Arthorn Animal Hospital, in Nakornpathom, Thailand, from January 2015 to March 2016. The traditional methods of Gram stain, mannitol fermentation, hemolysis on blood agar, catalase test, and coagulase production were used to confirm the presence of Staphylococcus aureus in all specimens. All bacterial isolates were determined by antimicrobial susceptibility test by the disk diffusion method. The polymerase chain reaction was used to identify the antimicrobial-resistant genes (blaZ, mecA, aacA-aphD, msrA, tetK, gyrA, grlA, and dfrG) in isolates of MRSA with a cefoxitin-resistant phenotype. From 218 specimens, 185 S. aureus were isolated, with the majority of these being found in the oral cavity (29.73%) and ventral thoracic area (22.7%), respectively. Forty-seven (25.41%) MRSAs were found in S. aureus isolates, with the majority of these being found in the perineum (16, 34.04%) and ventral thoracic area (13, 27.66%) specimens. Among MRSAs, 29 (61.7%) isolates were multidrug-resistant (MDR) strains. Most of MRSA isolates were resistant to penicillin (100%), followed by ceftriaxone (44.68%) and azithromycin (44.68%). In addition, these bacteria contained the most drug-resistance genes, blaZ (47.83%), followed by gyrA (36.17%) and tetK (23.4%). This study revealed that MRSA could be found even in healthy rabbits. Some MRSAs strains were MDR-MRSA, which means that when an infection occurs, the available antibiotics were not effective in treating it. To prevent the spread of MDR-MRSA from pets to owners, it may be helpful to educate owners about effective prevention and hygiene measures.

Numerical Analysis of Factors Influencing the Ground Surface Settlement above a Cavity

In this study, ground stability was evaluated through vertical displacement distribution and surface settlement results. In particular, a finite element analysis was conducted considering various factors (namely, cavity type and area, traffic load, pavement thickness, and elastic modulus) that affect a road above a cavity. The aim of this study was to evaluate the effect of pavement layer and traffic load condition on surface settlement according to the cavity shape. Field measurement results were analyzed and compared with the results of previous studies to verify the reliability of the numerical analysis method applied herein. After performing the numerical analysis using the verified method, ground stability was evaluated by analyzing the underground mechanical behavior of a road above a cavity. To this end, the correlations among the vertical displacement distribution, surface settlement, and influencing factors obtained from the analysis results were analyzed. In the numerical analysis, the ground was simulated with a hardening soil model based on the elastoplastic theory. This mechanical soil model can accurately reproduce the behavior of actual ground and can closely represent the mechanical behavior of the soil surrounding a cavity according to the cavity generation. In addition, the elapsed time was not considered when applying a load on the pavement layer, and a uniformly distributed load was applied. Consequently, it was found that, with increasing cavity area and traffic load and decreasing pavement thickness and elastic modulus, the vertical displacement and maximum surface settlement above the cavity increased, and the reduction in ground stability was greater. Furthermore, the reduction in ground stability was greater when the cavity was rectangular than when it was circular.