MyMedR

Displaying publications 61 - 80 of 191 in total

Abstract:

Sort:

Fulltext Overview of occupational noise management in Malaysia

Noraidah Ismail, Sarah Rahmat

International Journal of Allied Health Sciences, 2018;2(3):445-458.
MyJurnal

This paper aims to synthesize available literature on occupational noise in Malaysia and to relate this to the current noise management practices and control. The review focuses on several main
scopes; i) history of occupational noise management in Malaysia; ii) legislative developments and legal precedents of occupational noise in Malaysia ; and iii) the hearing conservation programs (HCP) and hearing loss prevention programs (HLPP). Narrative review and synthesis. Related publications and references were identified through several ways: i) by structured searches in PubMed, Google scholar, Web of Knowledge and Science Direct using the combinations of ‘occupational noise’, ‘noise induced hearing loss; ‘hearing’, ‘knowledge’, awareness’, ‘hearing conservation program’, ‘hearing protection devices’ as key words ii) by inspecting the reference lists of relevant articles. The number of publications within the audiology which address this topic, is rather limited. All the above mentioned scopes were discussed and synthesis of literature from other related fields such as medical, health and occupational safety and health were also referred to facilitate the discussion. This paper concludes that there are an emerging trend for the studies of occupational noise Malaysia in the literature. However, the effectiveness of HCP in Malaysia, and to what extent it is accepted and being implemented is yet to be investigated.

Matched MeSH terms: Hearing Loss, Noise-Induced; Noise, Occupational
Fulltext Morphological techniques for microcalcification and mass enhancement

Nor'aida Khairuddin, Norriza Mohd Isa, Wan Muhamad Saridan Wan Hassan

Journal of Nuclear and Related Technologies, 2012;2012(2):102-108.
MyJurnal

The recognition of microcalcifications and masses from digital mammographic images are important to aid the detection of breast cancer. In this paper, we applied morphological techniques to extract the embedded structures from the images for subsequent analysis. A mammographic phantom was created with embedded structures such as micronodules, nodules and fibrils. For the preprocessing techniques, intensity transformation of gray scale was applied to the image. The structures of the image were enhanced and segmented using dilation for a morphological operation with morphological closing. Next, low pass Gaussian filter was applied to the image to smooth and reduce noises. It was found that our method improved the detection of microcalcifications and masses with high Peak Signal To Noise Ratio (PSNR).

Matched MeSH terms: Noise; Signal-To-Noise Ratio
A study on compliance to hearing conservation programme among industries in Negeri Sembilan, Malaysia

Nor Saleha IT, Noor Hassim I

Ind Health, 2006 Oct;44(4):584-91.
PMID: 17085919

Noise is one of the hazards faced by workers. A cross-sectional study was conducted among industries in Negeri Sembilan with the objective to assess their compliance to Hearing Conservation Programme (HCP). The other objectives of this study were to determine the factors influencing it and to show the industries' compliance to each element of the programme. It was also to identify the association between compliance to HCP and the prevalence of hearing impairment and standard threshold shift. Data for this study were collected using questionnaires sent by mail and also the results of the latest audiometric tests. A total of 167 industries were analysed for this study. It was found that 41.3% of these industries fully complied to the programme. It was also found that the industries preferred to provide hearing protection device (92.8%) and least complied to noise control (61.1%). There were significant associations (p<0.05) between compliance and number of employees, status of ownership and the presence of officer in charge of hearing conservation programme. Having at least 150 employees actually raised the compliance to HCP in two folds (beta = 0.717, OR = 2.048, C.I 95% = 1.063 to 3.944). The prevalences of hearing impairment and standard threshold shift were 23.9% and 5.2% respectively. There was no significant association between the prevalence for hearing impairment and compliance to HCP. The prevalence for standard threshold shift was inversely related to compliance. This study showed that compliance percentage need to be improved as an effort to prevent the hearing problems among workers exposed to noise.

Matched MeSH terms: Hearing Loss, Noise-Induced/etiology; Hearing Loss, Noise-Induced/epidemiology; Hearing Loss, Noise-Induced/prevention & control*; Noise, Occupational/adverse effects*
Fulltext Improved architecture of speaker recognition based on wavelet transform and Mel Frequency Cepstral Coefficient (MFCC)

Nor Ashikin Rahman, Noor Azilah Muda, Norashikin Ahmad

Pertanika Journal of Science & Technology, 2017;25(106):1-10.
MyJurnal

Combining Mel Frequency Cepstral Coefficient with wavelet transform for feature extraction is not new. This paper proposes a new architecture to help in increasing the accuracy of speaker recognition compared with conventional architecture. In conventional speaker model, the voice will undergo noise elimination first before feature extraction. The proposed architecture however, will extract the features and eliminate noise simultaneously. The MFCC is used to extract the voice features while wavelet de-noising technique is used to eliminate the noise contained in the speech signals. Thus, the new architecture achieves two outcomes in one single process: ex-tracting voice feature and elimination of noise.

Matched MeSH terms: Noise
Pure-tone audiometry and auditory brainstem responses in noise-induced deafness

Noorhassim I, Kaga K, Nishimura K

Am J Otolaryngol, 1996 1 1;17(1):31-5.
PMID: 8801813

PURPOSE: The objective of this study is to find the relationship between pure-tone audiometry results and the auditory brainstem response wave abnormalities.
SUBJECTS AND METHODS: The pure-tone audiometry (PTA) and auditory brainstem responses (ABRs) from 22 patients (44 ears) with diagnosed noise-induced permanent hearing loss were studied. Three indices of PTA were average thresholds of 0.5 kHz/, /1 kHz, and 2 kHz (PTA1); 2 kHz and 4 kHz (PTA2); and 4 kHz (PTA3) were subdivided into 3 thresholds of hearing. Their relationships with ABR results were analysed. The patterns of PTA from various groups of ABR wave patterns were studied.
RESULTS: In this study, the abnormal ABR wave patterns were detected in 72.7% of the ears. The ears with prolonged ABR wave latency, absent early waves, prolong interpeak wave I-V latency was 20.5%, 18.2%, and 21.1%, respectively. Normal ABRs were recorded in 27.3% of the ears despite marked thresholds elevation of the PTA at high frequencies. Other relationships between PTA results and ABR wave results were discussed.
CONCLUSION: There were relationships between severity of noise-induced hearing loss indicated by PTA and the patterns of ABR wave abnormalities among workers with noise-induced permanent hearing loss.

Matched MeSH terms: Hearing Loss, Noise-Induced/diagnosis*
Fulltext Ambient noise reduction using improved least mean square adaptive filtering

Noor, A.O.A., Samad, S.A., Hussain, A.

ASM Science Journal, 2010;4(2):133-141.
MyJurnal

In this paper, an improved method of reducing ambient noise in speech signals is introduced. The proposed noise canceller was developed using a computationally efficient (DFT) filter bank to decompose input signals into sub-bands. The filter bank was based on a prototype filter optimized for minimum output distortion. A variable step-size version of the (LMS) filter was used to reduce the noise in individual branches. The subband noise canceller was aimed to overcome problems associated with the use of the conventional least mean square (LMS) adaptive algorithm in noise cancellation setups. Mean square error convergence was used as a measure of performance under white and ambient interferences. Compared to conventional as well as recently developed techniques, fast initial convergence and better noise cancellation performances were obtained under actual speech and ambient noise.

Matched MeSH terms: Noise
Effects of noise in the workplace

Noor Hassim I

Family Physician, 1991;3:14-16.

Matched MeSH terms: Noise
Fulltext Investigating brain activation and neural efficacy during simple arithmetic addition task in quiet and in noise: an fMRI study

Ng, Sok Bee, Ahmad Nazlim Yusoff, Teng, Xin Ling, Aini Ismafairus Abd. Hamid

Jurnal Sains Kesihatan Malaysia, 2014;12(1):23-33.
MyJurnal

Knowledge about the hemodynamic model that mediates synaptic activity and measured magnetic resonance signal is essential in understanding brain activation. Neural efficacy is a hemodynamic parameter that would change the evoked hemodynamic responses. In this work, brain activation and neural efficacy of the activated brain areas during simple addition task in two different backgrounds were studied using fMRI. The objectives were to determine the activated areas during the performance of arithmetic addition in quiet (AIQ) and noisy (AIN) background and to investigate the relationship between neural efficacy and height extent of activation for the respective areas. Eighteen healthy male participants performed simple arithmetic addition in quiet and in noise. Bilateral cerebellum, superior temporal gyrus (STG), temporal pole (TP) and supplementary motor area (SMA) were significantly (p < 0.05) activated during AIQ and AIN. Left middle frontal gyrus (L-MFG), right superior frontal gyrus (R-SFG), right superior orbital gyrus (R-SOG) and bilateral insula were more active in quiet as compared to in noise while the left middle cingulate cortex (L-MCC), left amygdala (L-AMG), right temporal pole (R-TP) and left cerebellum (L-CER) were more active in noise as compared to in quiet. The t value for most of the activated regions was found to be inversely proportional to the neural efficacy. Significant (p < 0.05) negative relationship between t value and neural efficacy were found for R-STG and bilateral cerebellum during AIQ, while for AIN, similar relationships were found in R-CER, R-STG and R-TP. This study suggests that while being significantly activated, the hemodynamic responses of these brain regions could have been suppressed by the stimulus resulting in an intensity decrease with increasing neural efficacy.

Matched MeSH terms: Noise
Fulltext Hearing loss and contributing factors among airport workers in Malaysia

Nasir MH, Rampal KG

Med J Malaysia, 2012 Feb;67(1):81-6.
PMID: 22582554 MyJurnal

Sensorineural hearing loss is a common and important source of disability among the workers and often caused by occupational noise exposure. Aims of the study were to determine the prevalence and contributing factors of hearing loss among airport workers. A cross-sectional study was carried out at an airport in Malaysia. This study used stratified sampling method that involved 358 workers who were working in 3 different units between November 2008 and March 2009. Data for this study were collected by using questionnaires eliciting sociodemographic, occupational exposure history (previous and present), life-style including smoking habits and health-related data. Otoscopic and pure-tone audiometric tests were conducted for hearing assessment. Noise exposure status was categorize by using a noise logging dosimeter to obtain 8-hour Time-Weighted Average (TWA). Data was analyzed by using SPSS version 12.0.1 and EpiInfo 6.04. The prevalence of hearing loss was 33.5%. Age >40 years old (aOR 4.3, 95%CI 2.2-8.3) is the main risk factors for hearing loss followed by duration of noise exposure >5 years (aOR 2.5, 95%CI 1.4-4.7), smoking (aOR 2.1, 95%CI 1.2-3.4), duration of service >5 years (aOR 2.1, 95%CI 1.1-3.9), exposure to explosion (aOR 6.1, 95%CI 1.3-29.8), exposure to vibration (aOR 2.2, 95%CI 1.1-4.3) and working in engineering unit (aOR 5.9, 95%CI 1.1-30.9). The prevalence rate ratio of hearing loss for nonsmokers aged 40 years old and younger, smokers aged 40 years old and younger, non-smokers older than 40 years old and smokers older than 40 years old was 1.0, 1.7, 2.8 and 4.6 respectively. This result contributes towards better understanding of risk factors for hearing loss, which is relatively common among Malaysian workers.

Matched MeSH terms: Hearing Loss, Noise-Induced/etiology*; Hearing Loss, Noise-Induced/epidemiology
Fulltext Development of speech materials for speech-in-noise training in adults

Nashrah Maamor, Nurul Huda Bani, Wan Syafira Ishak, Siti Zamratol Mai-Sarah Mukari, Kalaivani Chellapan

Jurnal Sains Kesihatan Malaysia, 2018;16(101):215-215.
MyJurnal

This paper describes the systematic process followed in the development of culturally appropriate equalized speech-in-noise sentences suitable for use in an adaptive Speech-In-Noise training protocol for adults in Malaysia. The process involved three iterative phases of development. They were (1) analysis, (2) design and (3) development phases. In the analysis phase, important variables that needed to be considered for speech-in-noise materials were identified through literature review and discussion with the experts in the field. Next, in the design phase, the compilation and formation of sentences, evaluation of naturalness and recording of the speech materials were done. The last phase was the development phase which involved the evaluation of performance intensity function and equalization of intelligibility. The final outcome of these phases were 171 sentences with equal intelligibility that can be used interchangeably in a speech-in-noise training protocol for adults in Malaysia.

Matched MeSH terms: Noise
Fulltext Relative contributions of auditory and cognitive functions on speech recognition in quiet and in noise among older adults

Mukari SZMS, Yusof Y, Ishak WS, Maamor N, Chellapan K, Dzulkifli MA

Braz J Otorhinolaryngol, 2018 12 10;86(2):149-156.
PMID: 30558985 DOI: 10.1016/j.bjorl.2018.10.010

INTRODUCTION: Hearing acuity, central auditory processing and cognition contribute to the speech recognition difficulty experienced by older adults. Therefore, quantifying the contribution of these factors on speech recognition problem is important in order to formulate a holistic and effective rehabilitation.
OBJECTIVE: To examine the relative contributions of auditory functioning and cognition status to speech recognition in quiet and in noise.
METHODS: We measured speech recognition in quiet and in composite noise using the Malay Hearing in noise test on 72 native Malay speakers (60-82 years) older adults with normal to mild hearing loss. Auditory function included pure tone audiogram, gaps-in-noise, and dichotic digit tests. Cognitive function was assessed using the Malay Montreal cognitive assessment.
RESULTS: Linear regression analyses using backward elimination technique revealed that had the better ear four frequency average (0.5-4kHz) (4FA), high frequency average and Malay Montreal cognitive assessment attributed to speech perception in quiet (total r2=0.499). On the other hand, high frequency average, Malay Montreal cognitive assessment and dichotic digit tests contributed significantly to speech recognition in noise (total r2=0.307). Whereas the better ear high frequency average primarily measured the speech recognition in quiet, the speech recognition in noise was mainly measured by cognitive function.
CONCLUSIONS: These findings highlight the fact that besides hearing sensitivity, cognition plays an important role in speech recognition ability among older adults, especially in noisy environments. Therefore, in addition to hearing aids, rehabilitation, which trains cognition, may have a role in improving speech recognition in noise ability of older adults.

Matched MeSH terms: Noise*
Medial olivocochlear functioning and speech perception in noise in older adults

Mukari SZ, Mamat WH

Audiol. Neurootol., 2008;13(5):328-34.
PMID: 18460868 DOI: 10.1159/000128978

The purposes of this study were to: (1) compare medial olivocochlear system (MOCS) functioning and speech perception in noise in young and older adults and (2) to quantify the correlation between MOCS functioning and speech perception in noise. Measurements were taken in 20 young (mean 26.3 +/- 2.1 years) and 20 older adults (mean 55.2 +/- 2.8 years). Contralateral distortion product otoacoustic emission (DPOAE) suppression was measured to assess MOCS functioning. Speech perception in noise was evaluated using the Hearing in Noise Test in noise-ipsilateral, noise-front and noise-contralateral test conditions. The results revealed that the older group had a significantly lower high-frequency (3-8 kHz) contralateral DPOAE suppression, and performed more poorly in the noise-ipsilateral condition than the younger group. However, there was no correlation between contralateral DPOAE suppression and speech perception in noise. This study suggests that poor speech perception performance in noise experienced by older adults might be due to a decline in medial olivocochlear functioning, among other factors.

Matched MeSH terms: Noise
Fulltext Er3+/Yb3+ co-doped fibre amplifier demonstrates significant gain enhancement with improved noise figure

Muhd-Yassin, S.Z., Harun, S.W., Ahmad, H., Abd-Rahman, M.K.

ASM Science Journal, 2008;2(2):163-168.
MyJurnal

An efficient erbium/ytterbium co-doped fibre amplifier was demonstrated by using a dual-stage partial doublepass structure with a band-pass filter (BPF). The amplifier achieved the maximum small signal gain of 56 dB and the corresponding noise figure of 4.66 dB at 1536 nm with an input signal power and total pump power of –50 dBm and 140 mW, respectively. Compared with a conventional single-stage amplifier, the maximum gain enhancement of 16.99 dB was obtained at 1544 nm with the corresponding noise figure was improved by 2 dB. The proposed amplifier structure only used a single pump source with a partial double pass scheme to provide a high gain and dual-stage structure to provide the low noise figure.

Matched MeSH terms: Noise
Fulltext Prevalence of occupational diseases among small and medium industry workers in Malaysia: a systematic review

Muhammad Zubir Yusof, Nik Ahmad Kamal Nik Mahmod, Nor Azlina A. Rahman, Ailin Razali, Niza Samsuddin, Nik Mohamed Nizan Nik Mohamed, et al.

Journal of Clinical and Health Sciences, 2019;4(2):4-30.
MyJurnal

Occupational diseases are one of the major health problems related to workplace hazards.
However, the epidemiological data for this problem is scarce especially among Small and
Medium Industry (SMI) workers. These workers are vulnerable to occupational health problem
due to lack of knowledge and implementation of health and safety in the workplace. In Malaysia,
most of the SMI workers have limited coverage for basic occupational health services which
may worsen their health. Thus, this article aims to provide a review on the burden of
occupational health problems among them. The electronic and library searches were used to
extract the information from both published and unpublished articles that were not limited to any
year of publication until 2017. One hundred and ninety-six published articles and 198
unpublished articles were retrieved from the database. Only 19 published articles and 25
unpublished articles met the eligibility criteria. Prevalence data of occupational
diseases/poisoning, including overall and body specific (musculoskeletal disorders) was
extracted in raw data from the eligible studies. Prevalent statistics on occupational
musculoskeletal diseases (1.3% - 97.6%), noise-induced hearing loss (29.4% - 73.3%),
occupational skin diseases (10.5% - 84.3%), respiratory (1.9% - 92.2%) and occupational
poisoning (14.9% - 17.7%) among the working population is different within published papers
compared to unpublished ones. In Malaysia, there are no specific statistic that give a true picture
of the burden of occupational diseases in the SMI. However, this review concludes that
musculoskeletal diseases are significant occupational problems among SMI workers.

Matched MeSH terms: Hearing Loss, Noise-Induced
Fulltext Otoscopic changes before and after shooting amongst military army personnel

Muhammad Izani Mohd Shiyuti, Irfan Mohamad, Dinsuhaimi Sidek

Malaysian Journal of Medicine and Health Sciences, 2014;10(1):7-11.
MyJurnal

The effect of loud noise to the army personnel is often identified when hearing loss had already developed. Acoustic trauma during shooting training can also lead to acute changes in the ear which is shown on otoscopic examination. This study was undertaken to determine the effectiveness of hearing protective device (earplug) on the prevalence of external ear changes amongst military personnel during shooting. This is a prospective cross sectional study that was conducted among 76 military personnel, who were divided into two groups: those with and without earplugs during shooting. Each participant underwent 3 otoscopic examinations: (a) pre-shooting, (b) immediate post-shooting (within 48 hours) and (c) 2 weeks after shooting. A total of 78 army personnel who were scheduled to undergo shooting training were otoscopically examined. Eighty three percent of them did not wear earplugs before. The percentage of inflammation of external auditory canal and tympanic membrane dullness increased tremendously among subjects from non–earplug group less than 48 hours post-shooting. Assessment after 2 weeks showed improvement in around 30% of the subjects. Loud noise has become an occupational hazard not only to the inner ear but it also predisposes the external and middle ear structures to some form of injury. Although improvement is seen after some period, a protective device such as an earplug should be recommended and the usage should be reinforced among the army personnel involved in shooting.

Matched MeSH terms: Hearing Loss, Noise-Induced; Noise
Simultaneous analysis of silicon and boron dissolved in water by combination of electrodialytic salt removal and ion-exclusion chromatography with corona charged aerosol detection

Mori M, Sagara K, Arai K, Nakatani N, Ohira S, Toda K, et al.

J Chromatogr A, 2016 Jan 29;1431:131-7.
PMID: 26755416 DOI: 10.1016/j.chroma.2015.12.064

Selective separation and sensitive detection of dissolved silicon and boron (DSi and DB) in aqueous solution was achieved by combining an electrodialytic ion isolation device (EID) as a salt remover, an ion-exclusion chromatography (IEC) column, and a corona charged aerosol detector (CCAD) in sequence. DSi and DB were separated by IEC on the H(+)-form of a cation exchange resin column using pure water eluent. DSi and DB were detected after IEC separation by the CCAD with much greater sensitivity than by conductimetric detection. The five-channel EID, which consisted of anion and cation acceptors, cathode and anode isolators, and a sample channel, removed salt from the sample prior to the IEC-CCAD. DSi and DB were scarcely attracted to the anion accepter in the EID and passed almost quantitatively through the sample channel. Thus, the coupled EID-IEC-CCAD device can isolate DSi and DB from artificial seawater and hot spring water by efficiently removing high concentrations of Cl(-) and SO4(2-) (e.g., 98% and 80% at 0.10molL(-1) each, respectively). The detection limits at a signal-to-noise ratio of 3 were 0.52μmolL(-1) for DSi and 7.1μmolL(-1) for DB. The relative standard deviations (RSD, n=5) of peak areas were 0.12% for DSi and 4.3% for DB.

Matched MeSH terms: Signal-To-Noise Ratio
Fulltext Assessment of traffic noise and the association with non auditory effect among shop lot workers in Kajang, Selangor

Mohd Zahiruddin Zukfali, Haliza Abdul Rahman

Malaysian Journal of Public Health Medicine, 2016;16(10):0-0.
MyJurnal

The objective of study is to determine traffic noise level and non-auditory effect among shop lot workers at Kajang Selangor. This cross sectional study was carried to study traffic noise exposure with annoyance and work performance level among shop lot workers in Jalan Mendaling, JalanTukang and Jalan Sulaiman at Kajang town, Selangor. This study involves 120 shop lot workers that exposed to the traffic noise during their working hours where they are randomly selected. Noise exposure was estimated using the Sound Level Meter for environmental noise. The traffic volume was recorded using video recorder and calculated using tally counter. One set questionnaire consist standard questionnaire was used to assess the annoyance level and work performance level among the respondents. Respondents were predominantly by male which are 94 and female, 26 respondents. The mean age of the respondent were ranged between 41 to 60 years old. Only 12.5% of respondent are ranged 21 until 30 years old. In total of 120 respondent, 54.2% of them are Chinese while Malay and India only 30% and 15.8% respectively. The result showed that the traffic noise level at study areas are exceeded the permissible sound limit of commercial and business area during daylight which is 70 dB(A). Regarding work performance, 94 respondents are having low work performance level and 82% of respondent high annoyance level during the exposure of traffic noise from four different sources which are noise from the traffic, speeding vehicle, high traffic volume and exhaust system. There is a significant relationship between traffic noise level with work performance level (p=0.001) and annoyance level (p=0.026). The average traffic noise (Laeq) level at Jalan Mendaling, Jalan Tukang and Jalan Sulaiman is 71.19 dB(A) which were high and exceeds permissible sound level from road traffic, commercial and business place at day time, 70 dB(A). The exposure from the traffic noise effect the annoyance level and work performance level among the shop lot worker. In order to reduce traffic noise exposure towards the shop lot workers, some recommendation are needed to control the traffic noise such as build a noise barrier, plant trees and also enforcement of legal requirement in noise level.

Matched MeSH terms: Noise
Fulltext Monitoring noise level during Sukhoi aircraft operation at no. 11 Squadron

Mohd Rizal Hamid, Ahmad Faruq Mohamad Rosli, Manokaran, Kesavan, Siti Shafiqa Shamira Hashin, Nik Mohd Dzarrin Ghifari Azmy, Baba Md Deros, et al.

ZULFAQAR International Journal of Defence Science, Engineering & Technology, 2020;3(2):25-31.
MyJurnal

Awareness of occupational noise and its effects is growing. At No. 11 squadron base, Sukhoi jet was identified as the main culprit of occupational noise that affects not just the employees of the base but also civilian people in the surrounding area. The objective of the study is to identify the noise level produced by Sukhoi two-engines jet during maintenance operations. Investigations were carried out using Bruel & Kjaer 2250 sound level meter hand-analyser. Measurements were performed directly under the Sukhoi jet body and then 10 metres, 50 metres, 100 metres, 1000 metres and 1500 metres away. The jet engines could operate at two levels, at 72% RPM and at 85% RPM. The civilians are only exposed to its noise from more than 1000 metres away. The results from this study are analysed and noise mapping and noise contouring are produced which give the level of noise exposure. The maximum noise is recorded t 122dB(A) and the minimum is at 60dB(A). The farther the noise from the jet is measured, the lower the values recorded. From the noise mapping, the effects of noise exposures on both the employees at the base and the civilian at the neighbouring surrounding could be identified. Even though the exposures are only for 5-10 minutes, it is still considered as a threat

Matched MeSH terms: Noise, Occupational
Widely tunable multi-wavelength Brillouinerbium fiber laser utilizing low SBS threshold photonic crystal fiber

Mohd Nasir MN, Yusoff Z, Al-Mansoori MH, Abdul Rashid HA, Choudhury PK

Opt Express, 2009 Jul 20;17(15):12829-34.
PMID: 19654689

A widely tunable low stimulated Brillouin scattering (SBS) photonic crystal fiber (PCF) based multi-wavelength Brillouin-erbium fiber laser is presented. The fiber laser structure utilizes a pre-amplified Brillouin pump (BP) technique with 100 m of PCF and a tunable band-pass filter within a Fabry-Perot cavity. A total of 14 Brillouin Stokes lines can be tuned over 29 nm from 1540 nm to 1569 nm. The wide tunability was only limited by the bandwidth of the tunable band-pass filter. A constant channel spacing of 0.079 nm and signal to noise ratio (SNR) of more than 20 dB for each Brillouin Stokes lines were also observed.

Matched MeSH terms: Signal-To-Noise Ratio
The outcomes of bilateral cochlear implant users in Universiti Kebangsaan Malaysia

Mohammad Azmi HH, Goh BS, Abdullah A, Umat C

Acta Otolaryngol, 2020 Oct;140(10):838-844.
PMID: 32564640 DOI: 10.1080/00016489.2020.1775887

INTRODUCTION: Bilateral cochlear implants are seen to improve hearing capabilities.
OBJECTIVE: To assess the auditory outcome of paediatric bilateral cochlear implant in Universiti Kebangsaan Malaysia.
MATERIALS AND METHODS: This was a cross-sectional and descriptive study single centre analysis. Categories of Auditory Performance (CAP-II) scale and Speech, Spatial and Qualities (SSQ) of Hearing questionnaire were used.
RESULTS: Forty-six patients were recruited. Majority of the children (30.4%) rated 7 and 23.9% scored perfectly (9) based on the CAP-II Scale. The least performing children were rated 5 (average). Children that were implanted sequentially within 24 months showed median CAP-II scale of 7. No significant correlation seen between CAP-II and the duration interval, use and age of 1st CI (p > .05). The speech domain of SSQ-P scale showed median value of 8 indicating good speech understanding. The spatial hearing domain had median value of 7, quality of hearing domain had median of 8. Significant correlation seen in hearing in noise with the duration of use of CI (p

Matched MeSH terms: Noise

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links