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Background and Objectives Patients with hearing loss and tinnitus experience difficulty in engaging in daily conversations. However, only few studies have examined how tinnitus affects individual speech discrimination to comprehend speech. This study aimed to analyze the correlation between tinnitus frequency and speech discrimination in patients with hearing loss and tinnitus.Subjects and Method A total of 275 ears with hearing impairment were retrospectively analyzed via audiometry and tinnitogram. The ears were divided into three groups depending on the frequency of their tinnitus. Average pure tone audiometry (PTA), hearing threshold of tinnitus frequency, speech discrimination test (SDT), degree of discrepancy between tinnitus frequency and worst PTA frequency were collected and compared among the three groups.Results No significant difference was observed in PTA in the three patient groups. Hearing threshold of tinnitus frequency was the highest at 78.27 dB in the high-frequency group and the lowest at 45.14 dB in the low-frequency group. SDT was significantly lower (53.69%) in the low-frequency group. The correlation between tinnitus loudness and SDT was the strongest in the low-frequency group. The degree of discrepancy between tinnitus frequency and worst PTA frequency was also significantly observed in the low-frequency group.Conclusion Patients who are severely affected by tinnitus are found to have significant discrepancy between tinnitus frequency and worst PTA frequency, indicating decreased SDT.

Background and Objectives There is no clear standard for the difference in the thresholds of auditory brainstem response (ABR) and pure tone audiometry (PTA) when using ABR to evaluate the reliability of PTA. Therefore, we assessed the difference in the thresholds of ABR and PTA for each frequency. Consequently, we present here the actual difference values between the two tests that can be used as a reference in the clinic.Subjects and Method We retrospectively assessed the audiometry results of 129 ears. Ears in which the hearing thresholds of each frequency continuously declined were classified as the downward group. We compared the average of differences between the two tests by frequency. The differences were compared for each hearing level from 50 dB or higher.Results For all ears, the appropriate range of difference value was ±5 dB at 2 kHz. At 1 kHz, the ABR threshold was 10 dB higher than PTA, and it was 10 dB less than PTA at 4 kHz. In the downward group, the difference value increased by 10 dB at 1 kHz and 4 kHz. In the subgroups at each hearing level, the difference value showed similar results (p

Background and Objectives The diagnosis of hearing impairment is based on repeated audiometry, including pure tone audiometry (PTA), speech reception threshold test (SRT), and speech discrimination test (SDT). SDT results particularly show a wide discrepancy upon repeated testing, while malingering is suspected when having more than 12% difference between 3 individual SDT results. Therefore, in this study, we compared the proportion of malingering found in repeated SDT with that found in other audiometric tests and analyzed the characteristics of malingering group in order to reevaluate the current criteria of defining malingering.Subjects and Method We retrospectively assessed the audiometry results of 113 patients (226 ears) with hearing impairment. Each ear was divided into a malingering group and a true hearing loss group. The proportion of ears corresponding to each malingering criterion was compared using a chi-square test. An independent sample t-test was performed to identify the differences between the characteristics between the two groups.Results The number of ears that met the malingering criteria were 19 (8.41%) in PTA, 15 (6.64%) in SRT, and 75 (33.19%) in SDT. There was a significant difference in the proportion of malingering between the 3 hearing test modalities (p

PURPOSE The objective of this study was to assess the impact of healthcare benefits on adherence to positive airway pressure (PAP) therapy in obstructive sleep apnea (OSA) patients. METHODS Medical records of OSA patients at the Veterans Health Service Medical Center were retrospectively reviewed. OSA patients were assigned to two groups as the date of prescribing PAP: after (=Group A) and before (=Group B) July 1, 2018 when PAP therapy starts to be included in healthcare insurance coverage for OSA patients in South Korea. PAP adherence was compared over a 3-month period between the two groups; subjective improvement after therapy was evaluated using the Epworth Sleepiness Scale (ESS) and Pittsburgh Sleep Quality Index scores. In addition, we evaluated a number of OSA patients who chose to start PAP therapy without healthcare benefit (from July 2018 to December 2018). RESULTS Each of the 50 patients in the Group A and B exhibited PAP adherence rates of 82% and 26%, respectively (P

As the mobile Internet has become widespread in recent years, communication based on mobile networks is increasing. As a result, security threats have been posed with regard to the abnormal traffic of mobile networks, but mobile security has been handled with focus on threats posed by mobile malicious codes, and researches on security threats to the mobile network itself have not attracted much attention. In mobile networks, the IP address of the data packet is a very important factor for billing purposes. If one mobile terminal use an incorrect IP address that either does not exist or could be assigned to another mobile terminal, billing policy will cause problems. We monitor and analyze 3G mobile data networks traffics for a period of time and finds some abnormal IP packets. In this paper, we analyze the reason for abnormal IP packets on 3G Mobile Data Networks. And we also propose an algorithm based on IP address table that contains addresses currently in use within the mobile data network to detect abnormal IP packets., {"references":["","CISCO, Global Mobile Data Traffic Forecast 2011-2016, Cisco Visual\nNetworking Index (VNI), 2012.","F. Ricciato, P. Svoboda, E. Hasenleithner, W. Fleischer, On the impact of\nunwanted traffic onto a 3G network, Proceedings of the Security, Privacy\nand Trust in Pervasive and Ubiquitous Computing, 2006, pp. 49-56.","3GPP, GPRS Tunnelling Protocol (GTP) across the Gn and Gp interface\n(Release 10), TS 29.060 V10.2.0, 2011.","H. Holma, A. Toskala, WCDMA for UMTS - Radio Access for Third\nGeneration Mobile Communications (Willey, 2004).","DARWIN Project, http://www.ftw.at/ftw/research/projects/","F. Ricciato, Traffic monitoring and analysis for the optimization of a 3G\nnetwork, Journal of Wireless Communication, Vol. 13, 2006, pp. 42-49.","ASMONIA Project, http://www.asmonia.de/"]}

Bot behavior analysis is an essencial component in botnet detection and response. Recent reseach on bot behavior analysis is focus on idenyifing wheather analysis target file is bot or not by monitoring user-level API call information of bot process and discover their malicous behaviors. However, such research does not monitor the bot process which has kernel-rootkit, anti-VM and static-DLL/binary code injection capabilities. In this paper, we present an approach based on a combination of System Call Layer rebuilding and process executing that enables automatic thwarting static-DLL/binary code injection. Also, we have built a system for analyzing advance bot behavior that can monitor the behavior of bot process at kernel-level and thwart some anti-vm methods. For experiments and evaluation, we have conduct experiments on several recent bot samples which have kernl-rootkit, anti-VM and static-DLL/binary code injection capabilities and shown that our system can successfully extrat their API call information and malicious behaviors from them.

In this paper, we propose a useful method for modeling multi-phased flows of P2P botnet traffic. Botnets are becoming more sophisticated and more dangerous each day and attackers use the P2P protocol to avoid centralized botnet topologies. We focus on the feature that a peer bot generates multiple traffic to communicate with large number of remote peers. In this case, phased botnet flows have similar patterns, which occur at irregular intervals. We compress duplicated flows via flow grouping and construct a transition model of the clustered flows using a probability-based matrix. A flow state is decided by features consisting of; protocol, port, and traffic. Our model involves transition information about the state values. Finally, we use the likelihood ratio for detection. In the experimental evaluation, we show the efficiency of our proposed system with the SpamThru, Storm, and Nugache botnets.

Purpose : To evaluate the incidence and type of low attenuation seen on high resolution computed tomogra-phy (HRCT) performed after artificially induced pulmonary embolism. Materials and Methods : Using permanent embolic materials, pulmonary embolism was induced in ten Yorkshire pigs. Pre- and postembolic pulmonary angiography was performed, and HRCT was performed im-mediately and 1, 3, and 6 weeks after embolization. The incidence and type of low attenuation of all segments, as seen on HRCT, was evaluated. Low attenuation was classified as mottled, lobular, segmental, or peripheral. The pigs were sacrified after 6 weeks and contact radiographs were obtained. Results : Low attenuation developed in eight of ten pigs. Pulmonary angiography revealed arterial occlusion in 15 large and 19 small segmental arteries (34 of 45 segments). In the remaining 11 segments, follow-up HRCT demonstrated areas of low attenuation. This was present in 25 of 35 segments (71%) as seen on HRCT images obtained immediately; in 16 of 41 segments (39 %) on images obtained 1 week after embolization; in 17 of 41 segments (41 %) on those acquired at 3 weeks; and in 25 of 45 segments (56 %) on those acquired at 6 weeks. The overall incidence of low attenuation was 83/166 (50 %). The types of low attenuation were mottled in 32/83 cases, lobular in 13/83, segmental in 13/83, and peripheral in 25/83. In large segmental arterial occlusion, the incidence of low attenuation on HRCT was 100% immediately, 57% at 1 week, 60% at 3 weeks, and 80 % at 6 weeks. In small segmental arterial occlusion, the incidence was 47%, 25 %, 11 %, and 21 % respectively. The overall incidence of low attenuation was 40/55 (73 %) in large segmental arterial occlusion and 18/71 ( 25%) in small segmental arterial occlusion. Conclusion : Low attenuation on HRCT is a finding of pulmonary embolism and is more common on HRCT performed immediately after embolization (71%) and in large segmental arterial occlusion (73%). Low attenu-ation on HRCT is an ancillary finding and may be useful in the diagnosis of pulmonary embolism.

Purpose : To evaluate the correlation between CT and pathologic findings of pulmonary fat embolism in rabbits. Materials and Methods : In 16 rabbits, pulmonary fat embolism was induced by intravenous injection of autol-ogous bone marrow(mean 3.3 mL). Chest CT scans were obtained immediately(within 1 hour), and 1, 3, and 7 days after embolization. The rabbits were divided into four groups. Group 1 underwent CT scanning immedi-ately after embolization, group 2 immediately and 1 day after embolization, group 3 immediately, 1 day and 3 days after embolization, group 4 immediately, 1 day, 3 days and 7 days after embolization. Pathologic speci-mens were obtained immediately after the last CT scan. Results : The earliest CT findings of pulmonary fat embolism in rabbits were peripheral lung lucency(16/16, 1 00 %), perivascular ground-glass (12/16, 75.0 %) and enlargement of the central pulmonary artery(11/16, 6 8 .8 %). Pathologically, perivascular ground-glass opacity correlated with extensive perivascular alveolar con-gestion and enlargement of the central pulmonary artery correlated with perivascular connective tissue edema and reactive pulmonary arterial engorgement. Peripheral lung lucency was probably caused by embolic occlu-sion of the pulmonary artery and decreased perfusion and air trapping induced by arterial and bronchial s-pasm associated with hypoxia. CT scans obtained 1 and 3 days after embolization showed nodules and patchy ground-glass opacity and consolidation. Aggregation of nodules resulted in patch opacities. Pathologically, pul-monary nodules correlated with focal inflammation surrounding an artery and parenchymal opacity correlat-ed with parenchymal consolidation and hemorrhagic edema. CT scans and pathologic specimens obtained 7 days after embolization showed improvement of parenchymal lung abnormalities. Conclusion : Pulmonary fat embolism in rabbits show CT and pathologic findings which vary with dynamic change. Typical earliest findings of pulmonary fat embolism were peripheral lung lucency, perivascular ground-glass opacity and enlargement of the central pulmonary artery.

Takayasu's arteritis is a chronic vasculitic disease of the aorta, its major branches and the pulmonary arteries, resulting in stenosing, occlusive or aneurysmal lesion. While the precise etiology of Takayasu's disease is unknown, an autoimmune mechanism or active tuberculous inflammation have been suggested. It is more common in young oriental women but has a rare incidence in children. We experienced a case of Takayasu arteritis type Ⅳ in an 8 years old girl. The diagnosis was made by physical examination and digital substraction aortography(DSA which showed narrowing of left common carotid artery, right subclavian artery and left renal artery. The perfusion defect at posterior segment of right upper lobe was noted in lung perfusion scan. Medical treatment and percutaneous transluminal angioplasty(PTA were performed. In addition to case report, a brief review of literature was added.