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"ABSTRAKIonizing radiation (IR) presents a risk to human health via DNA damage even when administered at low doses, such as those used in panoramic radiography. Objectives: This study used the comet assay to assess DNA damage in buccal mucosa cells consequent to X ray radiation from panoramic radiography. Methods: Twenty participants were recruited from among patients who underwent panoramic examinations at Prof. Soedomo Dental Hospital, Universitas Gadjah Mada, and divided into two groups of 10. Buccal mucosa cells were collected from all participants before exposure to IR and at 30 min or 24 h after exposure in groups 1 and 2, respectively, and subjected to a comet assay to assess DNA damage. Assay output images were analyzed using OpenComet software. Double-strand breaks (DSBs) were assessed by comparing the percentages of tail DNA in output images obtained before and after X ray exposure. Results: A statistically signifcant (p 0.014) increase in the percentage of tail DNA was observed at 30 min after exposure, but not at 24 h (p 0.29). Conclusion: Panoramic X ray radiation may induce DSBs in human buccal mucosal cells within 30 min after exposure. "

"Kualitas berkas yang dinyatakan dalam besaran Half Value Layer (HVL) perlu diukur secara berkala pada saat proses uji jaminan mutu pesawat sinar-X. Penelitian ini mengembangkan sebuah model komputasi yang mampu memprediksi nilai HVL dari sebuah citra kosong radiografi umum untuk mengatasi permasalahan instalasi radiologi dalam pengadaan detektor radiasi. Model dibuat menggunakan teknik regresi Artificial Neural Network (ANN) dengan memanfaatkan nilai-nilai fitur yang dapat diekstrak dari sebuah citra medis sebagai masukan model. Tiga jenis model dibuat dengan memvariasikan jenis fitur masukan yang digunakan, yaitu fitur langsung, fitur tidak langsung atau properti Gray-Level Co-occurrence Matrix (GLCM), dan gabungan keduanya. Model dilatih menggunakan arsitektur dan hyper-parameters yang telah ditentukan hingga menghasilkan nilai galat terendah. Nilai HVL sebenarnya diukur menggunakan Solid-State Detector (SSD) dan digunakan untuk mengevaluasi performa model yang telah dilatih. Model Gabungan atau model dengan fitur masukan berupa gabungan antara jenis fitur langsung dan tidak langsung menghasilkan nilai performa terbaik. Pengujian performa Model Gabungan menggunakan data uji menghasilkan nilai mean absolute error, root mean squared error, dan mean absolute percentage error masing-masing sebesar 0,006, 0,009, dan 0,248%. Model harus diperlakukan sebagaimana detektor radasi pada umumnya sehingga proses akuisisi citra berulang perlu dilakukan. Perbedaan model pesawat sinar-X dan reseptor citra menghasilkan nilai dan pola fitur yang berbeda

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The beam quality stated in Half Value Layer (HVL) value needs to be measured periodically during Quality Assurance (QA) X-rays device. This study develops a computational model that can predict the HVL value from a general radiography empty image to solve the problems of radiology installations in the procurement of radiation detectors. The model was created using Artificial Neural Network (ANN) regression technique by utilizing feature values that can be extracted from a medical image as model input. Three types of models were created by varying the type of used input features, those were direct features, indirect features or Gray-Level Co-occurrence Matrix (GLCM) properties, and combination of both. The model was trained using the predefined architecture and hyper-parameters until producing the lowest error value. The real HVL value was measured using a Solid-State Detector (SSD) and used to evaluate the performance of the trained model. Combined Model or a model with an input feature in the form of a combination of the types of direct features and indirect features produced the best performance value. The performance test of the Combined Model using the test data produced the mean absolute error, root mean squared error, and mean absolute percentage error value of 0,006, 0,009, and 0,248%, respectively. The model must be treated as a radiation detector in general so that the repeated image acquisition is necessary. Differences in the X-ray device and the image receptor model produce different feature values and patterns."

"Diffusion in solids at moderate temperatures is a well-known phenomenon. However, direct experimental evidence about the responsible atomic-scale mechanisms has been scarce, due to difficulties in probing the relevant length- and time-scales. The present thesis deals with the application of X-ray Photon Correlation Spectroscopy (XPCS) for answering such questions. This is an established method for the study of slow dynamics on length-scales of a few nanometres. The scattered intensity in the diffuse regime, i.e. corresponding to atomic distances, is very low, however, and so it has so far been considered impossible to use XPCS for this problem.Threefold progress is reported in this work. It proposes a number of systems selected for high diffuse intensity, it optimizes the photon detection and data evaluation procedures, and it establishes theoretical models for interpretating the results. Together these advances allowed the first successful atomic-scale XPCS experiment, which elucidated the role of preferred configurations for atomic jumps in a copper-gold alloy. "

"Cellular responses to stress including DNA damage show multiple options involving the mechanisms of growth arrest, DNA repair and programmed cell death or apoptosis. Failures in these mechanisms can result in oncogenesis or accelerated senescence. Much of the response is coordinated by p53, a nuclear phosphoprotein with a central role in the defences against physical, chemical and pathogenic agents which challenge the DNA integrity. The p53 pathways for mobilising the cellular defences are linked to the pRb/E2F pathways regulating the cell cycle progression. This paper aims to review the current understanding on the networks and main molecular machinery of these processes. In addition, the implications on cellular decision making for the defences as well as evolutionary aspects of these mechanisms are discussed in brief."

"ABSTRAKPenelitian ini bertujuan mengetahui perbedaan nilai mAgNOR antara kelompok perokok kretek dan bukan perokok dan mengetahui hubungan karakteristik perokok dengan nilai mAgNOR. Metode penelitian analitik komparatif dengan pendekatan potong lintang. Pengambilan spesimen menggunakan sikat oral pada mukosa bukal tampak normal dari 21 laki-laki usia 26-35 tahun pada masing-masing kelompok. Hasilnya, nilai mAgNOR pada kelompok perokok kretek (2,9543±0,35537) lebih tinggi daripada kelompok bukan perokok (2,6971±0,43732), secara statistik signifikan. Tidak terdapat hubungan antara nilai mAgNOR dengan karakteristik intensitas merokok, lama tahun kebiasaan merokok dan lama terpapar rokok. Terdapat hubungan antara mAgNOR dengan karakteristik lama menghabiskan 1 batang rokok (p=0,030, r=0,475).

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ABSTRACTThe aim of this study is to determine the difference between mAgNOR counts of kretek smokers and nonsmokers, and determine the relationship of smokers characterstics with mAgNOR counts. This comparative analytical research with cross sectional approach. Specimen using oral brush on the buccal mucosa appears normal of 21 men aged 26-35 years old in each group. As a result, mAgNOR counts of the smokers group (2,9543±0,35537) is higher than nonsmokers group (2,6971±0,43732), statistically significant. There was no correlation between mAgNOR counts with intensity of smoking, years and exposure time to kretek smoke. There was a correlation between mAgNOR counts with timing spend per smoke (p=0,030, r=0,475)."

"Radiografi dental panoramik merupakan teknik pencitraan gigi ekstraoral dengan menggunakan sinar-X. Penelitian tersebut dilakukan di RS. Pelni Petamburan dan RSUPN Cipto Mangunkusumo. Telah dilakukan pengukuran dosis kulit terhadap phantom radiografi kepala serta dosis kulit pasien radiografi dental panoramik menggunakan thermoluminiscence dosemerer (TLD). Jumlah pasien pemeriksaan radiografi dental panoramik adalah 20 orang dengan rentang umur 20-70 tahun masing-masing 10 orang untuk RS. Pelni Petamburan dan RSUPN Cipto Mangunkusumo. Pengukuran dosis kulit dilakukan dengan meletakkan TLD di empat titik, yaitu 1 rahang kiri, rahang kanan, mulut, dan tiroid.

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Panoramic dental radiography is a technique of extraoral dental imaging which use X-ray. This research has been carried out in RS. Pelni Petamburan and RSUPN Cipto Mangunkusumo. Skin doses has been measured to a head radiography phantom and to patients of panoramic dental radiography by using thennoluminiscence dosimeter (TLD). The patients are 20 persons whose age between 20-70 years old and 10 persons for each hospitals. Measurement of skin doses has been done by positioning TLDs at four places: left jaw, right jaw, mouth, and thyroid."

"Close proximity of the maxillary roots and the sinus floor makes a dental disease a probable cause of maxillary sinusitis. The aim of this study was to evaluate the ability of periapical radiography and cone beam computed tomography in defining the topographic relationship of maxillary teeth to the sinus floor and detecting apical periodontitis and other odontogenic causes of the maxillary sinusitis. Out of 145 dental records from subjects (mean age 52 years, range 20-75 years; 89 females) referred to the Oral Imaging Centre, KU Leuven, periapical and CBCT images of the posterior maxilla were selected for further analysis. Anatomical relationship of maxillary teeth to the sinus floor, apical periodontitis and other etiological causes of soft tissue thickening were assessed with both imaging modalities. The results of this study demonstrated that periapical radiographs are not adequate in observing the anatomical relationship between maxillary molars and the sinus floor. CBCT showed an intimate relationship of 1st and 2nd molar with the maxillary sinus in 50 and 45% of the cases, respectively. Periapical radiography could only spot approximately 40% of apical periodontitis on posterior maxillary teeth and 3% of all apical infections extending to the sinus, seen on CBCT."

"In order to asseses the risks associated with worker's hearing loss, due toRisk assess exposure to noise pollution, at the Boroujerd textile factory a cross sectional study was conducted. 60 workers from the spinning and weaving workshops and official staff were randomly selected as case and control groups to the noise pollution in the spinning and weaving workshops there is a distinct increase in the number of cases of hearing loss at hight frequences."