Displaying publications 61 - 80 of 104 in total

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  1. Marina M.B., Hazleigh N.M., Thean, Y.K., Sani A.
    MyJurnal
    Isolated lower cranial nerve (CN) palsy affecting the CN X resulting from a skull base fracture is very rare. The clinical manifestation and natural history is related closely to the complex anatomy of this region and mechanism of injury. Here, we report a case of a 54 year-old man who presented with a delayed onset of dysphonia and dysphagia with aspiration following a closed head injury sustained from a motor vehicle accident. Injection laryngoplasty was implemented to alleviate symptoms of his CN X palsy, which eventually almost completely resolved. High index of suspicion should be maintained when investigating possible skull base fractures, especially with a suggestive clinical presentation of lower CN palsies affecting one or all the lower CNs. Delayed onset of these CN palsies are likely to have more favourable outcomes.
    Matched MeSH terms: Motor Vehicles
  2. Kow RY, Mustapha Zakaria Z, Khan ESKM, Low C
    J Orthop Case Rep, 2019 3 28;8(6):65-67.
    PMID: 30915298 DOI: 10.13107/jocr.2250-0685.1262
    Introduction: Fracture of the ulnar coronoid process is uncommon. It is commonly associated with posterior dislocation of the elbow, but it may also present as an isolated fracture. In general, all ulnar coronoid process fractures with elbow joint instability and large fracture fragments are fixed surgically. We report two cases of the rare isolated Regan-Morrey type III ulnar coronoid process fractures and their outcomes.

    Case Report: Case Report 1: Mrs P, a 27-year-old right-hand dominant female, was involved in a motor vehicle accident (MVA) and sustained an isolated Regan-Morrey type III ulnar coronoid process fracture. In view of the large coronoid process fragment causing elbow joint instability, she underwent an open reduction and internal fixation when the elbow swelling had subsided. An anterior approach was used to identify the fracture fragment and it was fixed with two half-threaded cancellous lag screws with washers to achieve an anatomical reduction. Postoperatively, she recovered with excellent outcome based on the Mayo elbow performance score (MEPS).Case Report 2: Mr M, a 23-year-old right-hand dominant gentleman, was involved in a MVA and sustained an isolated Regan-Morrey type III ulnar coronoid process fracture. During examination under general anesthesia, passive range of the movement of his right elbow was noted to be <90°due to the impaction of the fracture fragment. An open reduction through an anterior approach was performed and Kirschner wires were inserted to fix the coronoid process fracture. Kirschner wires were opted for the ease of post-operative removal as the patient was not keen to have a retained implant after recovery. He recovered with good outcome based on the MEPS.

    Conclusion: Isolated fracture of the ulnar coronoid process is rare. Open reduction and internal fixation is mandatory for patients with coronoid process fracture and unstable elbow joint to achieve good functional outcomes.

    Matched MeSH terms: Motor Vehicles
  3. Fadzullah NA, Kasthuri S, Basiron N
    Med J Malaysia, 2019 Oct;74(5):452-453.
    PMID: 31649230
    According to the Malaysian Department of Statistics motor vehicle accidents are the third leading cause of death in Malaysia and accounts for 7.4% of premature deaths in 2016. With the invention of the airbag, the number of serious injuries and fatalities have been reduced significantly. However, there has also been a corresponding increase in the number of injuries attributable to these devices. The patient narrated in this case report sustained a mixed dermal thickness burn over the upper limb as a result of an airbag deployment. She recovered without other life threatening injuries.
    Matched MeSH terms: Motor Vehicles
  4. Oslan SNH, Tan JS, Abbasiliasi S, Ziad Sulaiman A, Saad MZ, Halim M, et al.
    Microorganisms, 2020 Oct 24;8(11).
    PMID: 33114463 DOI: 10.3390/microorganisms8111654
    Growth of mutant gdhA Pasteurella multocida B:2 was inhibited by the accumulation of a by-product, namely ammonium in the culture medium during fermentation. The removal of this by-product during the cultivation of mutant gdhA P. multocida B:2 in a 2 L stirred-tank bioreactor integrated with an internal column using cation-exchange adsorption resin for the improvement of cell viability was studied. Different types of bioreactor system (dispersed and internal) with resins were successfully used for ammonium removal at different agitation speeds. The cultivation in a bioreactor integrated with an internal column demonstrated a significant improvement in growth performance of mutant gdhA P. multocida B:2 (1.05 × 1011 cfu/mL), which was 1.6-fold and 8.4-fold as compared to cultivation with dispersed resin (7.2 × 1010 cfu/mL) and cultivation without resin (1.25 × 1010 cfu/mL), respectively. The accumulation of ammonium in culture medium without resin (801 mg/L) was 1.24-fold and 1.37-fold higher than culture with dispersed resin (642.50 mg/L) and culture in the bioreactor integrated with internal adsorption (586.50 mg/L), respectively. Results from this study demonstrated that cultivation in a bioreactor integrated with the internal adsorption column in order to remove ammonium could reduce the inhibitory effect of this by-product and improve the growth performance of mutant gdhA P. multocida B:2.
    Matched MeSH terms: Motor Vehicles
  5. Shamala N., Faizal, A.H.
    Medicine & Health, 2018;13(2):202-207.
    MyJurnal
    Trauma is thought to complicate 1 in 12 pregnancies. The management of trauma during pregnancy requires special consideration because pregnancy alters maternal physiology and the foetus is a potential collateral victim. The approach of these cases in the setting of the Emergency Department should not only be diagnostic for any foetal injuries but also prognostic for any future undue outcome. Antenatal traumatic brain injury is a rare but real complication of maternal blunt force trauma. Our case involves a 22-year-old primigravida who suffered a motor vehicle accident and on initial assessment revealed normal foetal assessment but subsequently after premature labour revealed a new born with traumatic brain injury. Early ultrasonographic evaluation and observational period with continuous electronic foetal monitoring may improve the detection and emergent treatment in these cases.
    Matched MeSH terms: Motor Vehicles
  6. Ganju A, Goulart AC, Ray A, Majumdar A, Jeffers BW, Llamosa G, et al.
    J Multidiscip Healthc, 2020;13:693-707.
    PMID: 32801732 DOI: 10.2147/JMDH.S252300
    Non-communicable diseases (NCDs) have been on the rise in low- and middle-income countries (LMICs) over the last few decades and represent a significant healthcare concern. Over 85% of "premature" deaths worldwide due to NCDs occur in the LMICs. NCDs are an economic burden on these countries, increasing their healthcare expenditure. However, targeting NCDs in LMICs is challenging due to evolving health systems and an emphasis on acute illness. The major issues include limitations with universal health coverage, regulations, funding, distribution and availability of the healthcare workforce, and availability of health data. Experts from across the health sector in LMICs formed a Think Tank to understand and examine the issues, and to offer potential opportunities that may address the rising burden of NCDs in these countries. This review presents the evidence and posits pragmatic solutions to combat NCDs.
    Matched MeSH terms: Motor Vehicles
  7. Chan YM, Agamuthu P, Mahalingam R
    J Hazard Mater, 2000 Oct 02;77(1-3):209-26.
    PMID: 10946129
    Currently, the generated brake lining waste dust, which contains asbestos as its major component, is disposed of into a secure landfill without any additional treatment. As an alternative to this, solidification/stabilization (S/S) disposal of the dust was investigated using Portland cement alone and Portland cement mixed with activated carbon (AC), as the binders. Toxicity Characteristics Leaching Procedure (TCLP) results on the solidified matrix showed that cement was able to immobilize the heavy metals, Ba, Zn, Cr, Pb, Cu and Fe, to within the limits set by the US EPA for TCLP. Addition of AC to the cement reduced the leaching of heavy metals by an additional 4-24% compared to cement alone. The pH of the TCLP leachate extracted from virgin cement, and from dust treated with cement with or without AC was found to increase to 10.9-12.5 as opposed to an initial value of 4.93 for the TCLP extract for the untreated dust. Results of ANS 16.1 (modified) leach protocol revealed that Ba in cement-treated samples showed the highest leach rate, followed by Zn, Pb, Cr, Cu and Fe. The leach rate of heavy metals decreased with progress in time. Cement mixed with AC exhibited similar leach characteristics, however, the leach rate was lower. The linear relationship between the cumulative fraction leached (CFL) and the square root of leaching time in all cement-based samples indicate that a diffusional process is the controlling transport mechanism for the leaching of the heavy metals. The obtained Leachability Indices (L(i)) of 7.6-9.1 and 8.3-9.5 for cement and cement with AC, respectively, were low but exceeded the guidance value of 6, which clearly indicates that all the heavy metals studied are retained well within solid matrices. Cement-based S/S hardening times increased from 30 to 96 h as the dust content increased from 40 to 70 wt.%. The resulting solid matrices exhibited a compressive strength ranging from 1 to 12 MPa, which was well above the specified limit of 414 kPa for such matrices. An economic analysis indicates that the disposal costs for the dust in the only available secure landfill would increase by 40.3% if one were to go for the cement S/S option. Addition of AC to the cement would escalate this by an additional 43.8%. Although the S/S of brake lining dust using cement effectively immobilized the heavy metals of concern, cost considerations may hinder the commercial adaptation of this technique for waste disposal unless new regulatory demands are implemented.
    Matched MeSH terms: Motor Vehicles
  8. Irfan Mohamad, Arumugam, Puvan Arul, Nik Fariza Husna Nik Hassan
    MyJurnal
    An 11-year-old Malay boy was allegedly involved in motor vehicle accident. He sustained left lung contusion and pneumothorax which necessitate chest tube insertion at a district hospital. On arrival at Accident & Emergency Unit, general physical examination was performed. Neck examination revealed multiple jagged lacerations wound on the left side of the neck (Panel 1). (Copied from article).
    Matched MeSH terms: Motor Vehicles
  9. Kamali U, Pohchi A
    MyJurnal
    This is a retrospective study to determine the distribution site, associated fracture and causes of mandibular fractures at HUSM, over a 5 year period, from 1st January 2002 - 31st December 2006. Records of patients who had mandibular fracture were reviewed. Data of age, sex, site of fracture, causes and associated fracture were recorded and analyzed using SPSS version 15.0. There were 113 (84.3%) males and 21 (15.7%) females. The mean age for male was 84.3% and female was 15.7%. The fracture occurs mostly at the age of 11-20 years (45.5%), followed by 21-30 years (30.6%). Motor vehicle accidents (MVA) were the commonest causes of mandibular fracture (92.5%), followed by fight and assault (3.7%), industrial accidents (3.0%), fall (0.7%). There were no cases recorded due to sport injury. The commonest site of mandibular fracture occurs at angle and para-symphysis (23%), followed by body (20.1%), symphysis (16.7%), condyle (15.5%) and ramus (1.7%). The most common associated fractures were head injury (23.5%), followed by clavicle fracture (17.2%) and fracture of radius (10.7%). Mandibular fracture was common in males with the mean age 24.63 years and mostly due to MVA. Angle and para-symphysis is the commonest site of mandibular fracture with most of the patient suffered from concomitant head injury.
    Matched MeSH terms: Motor Vehicles
  10. Anita, A.R., Yazdani, A., Hayati, K.S., Adon, M.Y.
    MyJurnal
    Automotive industry in Malaysia is one of the booming industries which encompass the design, development and manufacturing of motor vehicles. However, it has its own setback as the interaction between complex tools, machines, and instruments, coupled with humans as workers pose several health hazards. A cross-sectional study was conducted to determine the prevalence of musculoskeletal disorders (MSD) and the association with awkward posture among automotive assembly line workers. A simple random sampling method was adopted and data were collected based on Standardized Nordic Questionnaire (SNQ) and Rapid Upper Limb Assessment (RULA) method for analysing awkward posture. With a response rate of 83%, a total of 232 assembly line workers with at least one year job tenure participated in this study. The findings revealed that 78.4% of workers reported MSD while the highest percentage of complaints concerned the lower back (50.9%). Three factors were found to be significantly associated with MSD: age (χ2=5.61, p=0.018), job tenure (χ2= 8.26, p=0.004) and awkward posture (χ2= 65.37, p < 0.001). Logistic regression analysis indicated that significant risk factors for MSD symptoms were workers aged ≥ 25 years old (OR= 2.25, 95%CI 1.14-4.46) and those workers with equal and more than three years job tenure (OR= 2.44, 95%CI 1.04-5.63). In addition, workers in the very high and high RULA action level who were 69 times (OR = 69.38, 95%CI 14.51- 331.73) and 12 times (OR = 12.42, 95%CI 5.21-29.58), respectively, also had higher odds of complaints of MSD. The high prevalence of MSD shows that MSD symptoms is a significant problem among automotive assembly line workers while age, job tenure and awkward posture based on RULA action level are the significant factors for MSD. In particular, this study proves that the prevalence of MSD increases as the RULA action level and job tenure increases. Thus, this problem could be reduced by decreasing RULA action level through appropriate ergonomic workstation design and ergonomic training for workers.
    Matched MeSH terms: Motor Vehicles
  11. Rafidah Bahari, Muhammad N Mohamad Alwi, Muhammad R Ahmad, Ismail Mohd Saiboon
    ASEAN Journal of Psychiatry, 2015;16(2):203-211.
    MyJurnal
    There are a number of validated questionnaires available for the screening of Post-Traumatic Stress Disorder (PTSD), and the PTSD Checklist for Civilians is one of them. However, none was translated into the Malay Language and validated for use in the Malaysian population. The aim of this study is to translate and validate the Malay PTSD Checklist for Civilians (MPCL-C). Methods: The PCL-C was translated into the Malay Language and back-translated. The reliability and validity of the MPCL-C were then determined by administering them to those who presented at the emergency department for motor vehicle accident at least one month before. Results: The MPCL-C has good face and content validity. In terms of reliability, it is also good, with Chronbach’s alpha values of 0.90, 0.77, 0.75 and 0.74 for the full scale, re-experiencing, avoidance and arousal domains respectively. Conclusions: The MPCL-C is a valid and reliable instrument to screen for PTSD in motor vehicle accident victims for the studied population.
    Matched MeSH terms: Motor Vehicles
  12. Shamsiah A. Rahman, Mohd Suhaimi Hamzah, Abdul Khalik Wood, Md Suhaimi Elias, Nazaratul Ashifa Abdullah Salim, Ezwiza Sanuri
    MyJurnal
    Chemical composition of fine (PM2.5) aerosol samples collected for the 5 years period (2001- 2005) using Gent Stacked filter unit sampler at Klang Valley (3 o 10 ’ 30 ’’ N, 101 o 43 ’ 24 ’’ E) were analysed using Neutron Activation Analysis (NAA) and Proton Induced X-ray Emission (PIXE). Results of the study show that the major component of the fine aerosol was black carbon and sulfur with the mass concentration ranged from 4.4 - 6.7µg m -3 and 1.2 - 1.9µg m -3 , respectively. The total fine aerosol mass concentration were in the ranged of 25 - 31µg m -3 with the reconstructed mass was about 50% as relative to the gravimetric mass. Statistical method, factor analysis with varimax approach has been applied to the aerosol composition data for the fingerprint identification. The analysis produces five identified fingerprint represent soil, industry, motor vehicles/biomass burning and Pb and Zn sources. There is also an unidentified source that could be related to unknown industrial activities.
    Matched MeSH terms: Motor Vehicles
  13. Hamidon, B.B., Md Shariful, H.S., Nasaruddin, M.Z.
    MyJurnal
    Traumatic bilateral sixth cranial nerve palsy is a rare condition which is typically associated with additional intracranial, skull, and cervical spine injuries. We describe a case of complete bilateral sixth nerve palsy in a 28-year-old female patient after an alleged motor vehicle accident. She had altered level of consciousness but no intracranial lesion or associated skull or cervical spine fracture was detected. In this case, we discussed the differential diagnoses, initial workup, and possible treatment options in cases of traumatic 6th nerve palsy.
    Matched MeSH terms: Motor Vehicles
  14. Jefferelli SB, Limi L
    MyJurnal
    We do not know how medical doctors perceive the risk of cancer as a cause of death. Medical doctors provide advice and information on health risks to the general public. How they perceive these risks influences the way they behave towards these risks and the way they will communicate these risks. We would like to ascertain how medical students perceive cancer as a health risk. This will hehv us determine misperceptions among medical students that need to be addressed before they practice medicine. A cross-sectional study was conducted among
    all UPM medical students (2000-2001) using sefadministered questionnaires. A total of 339 (88.3%) students responded to the questionnaires. The internal consistency of items was good (Cronbach Alpha >0,7). Cancer was perceived as the 3rd leading risk of death after motor vehicle accidents (I") and heart diseases/cardiovascular disorders (2"d ). The breast was perceived as the organ with the highest risk of developing cancer. Smoking was perceived to be the leading risk factor for developing cancer. There is a dpjference in risk perception of diseases, cancer target organs and cancer risk factors based on gender and ethnicity. There was moderate to fair correlation ( r = 0.41-0.57) between perception of risks of death, cancer target organs and risks factors of cancer (p
    Matched MeSH terms: Motor Vehicles
  15. Chang CC, Saad B, Surif M, Ahmad MN, Md Shakaff AY
    Sensors (Basel), 2008 Jun 01;8(6):3665-3677.
    PMID: 27879900
    A disposable screen-printed e-tongue based on sensor array and pattern recognition that is suitable for the assessment of water quality in fish tanks is described. The characteristics of sensors fabricated using two kinds of sensing materials, namely (i) lipids (referred to as Type 1), and (ii) alternative electroactive materials comprising liquid ion-exchangers and macrocyclic compounds (Type 2) were evaluated for their performance stability, sensitivity and reproducibility. The Type 2 e-tongue was found to have better sensing performance in terms of sensitivity and reproducibility and was thus used for application studies. By using a pattern recognition tool i.e. principal component analysis (PCA), the e-tongue was able to discriminate the changes in the water quality in tilapia and catfish tanks monitored over eight days. E-tongues coupled with partial least squares (PLS) was used for the quantitative analysis of nitrate and ammonium ions in catfish tank water and good agreement were found with the ion-chromatography method (relative error, ±1.04- 4.10 %).
    Matched MeSH terms: Motor Vehicles
  16. Hayat MN, Kaka U, Sazili AQ
    Foods, 2021 Apr 16;10(4).
    PMID: 33923538 DOI: 10.3390/foods10040874
    Cold truck transportation is considered one of the most integral parts in a food processing chain. However, countless cases of product spoilage and food poisoning incidents have proven that temperature control during transport has been neglected. Literature on the impact of temperature during distribution is scarce. The objective of this study was to investigate the impact of various transportation temperatures and travel duration on the meat quality and microbial population of broiler chicken breast muscle. Sixty broiler chickens (42 days old) were slaughtered and eviscerated; they then had their breast muscles removed (each bird provided two breast muscle samples: left breast and right breast), which were wrapped in plastic film. All 120 packed boneless breasts (PBBs) were then placed at -18 °C for 24 h. After 24 h, the 60 PBB samples were subjected to transportation for 1 h at 4 °C (20 PBBs), 10 °C (20 PBBs), and 15 °C (20 PBBs) while the remaining 60 samples were transported for 5 h at 4 °C (20 PBBs), 10 °C (20 PBBs), and 15 °C (20 PBBs) before analyses. The samples transported at higher temperatures exhibited higher populations of coliform and Salmonella than those transported at lower temperatures. A significant impact of the transportation duration on the Salmonella population was only observed in samples transported at 4 °C for 5 h. However, a significant impact of transportation temperature on color was only recorded for the redness (a*) values, where the samples transported at higher temperatures exhibited higher redness (a*) values. Significant increases in lightness (L*) and yellowness (b*) values as well as decreases in redness (a*) and pH values were recorded in samples subjected to longer durations of transportation across all the temperatures observed in this study.
    Matched MeSH terms: Motor Vehicles
  17. Syed Hassan ST, Jamaludin H, Abd Raman R, Mohd Riji H, Wan Fei K
    Trauma Mon, 2013 Sep;18(2):56-61.
    PMID: 24350153 DOI: 10.5812/traumamon.11522
    CONTEXT: As with care giving and rehabilitation in chronic illnesses, the concern with traumatic brain injury (TBI), particularly with diffuse axonal injury (DAI), is that the caregivers are so overwhelmingly involved in caring and rehabilitation of the victim that in the process they become traumatized themselves. This review intends to shed light on the hidden and silent trauma sustained by the caregivers of severe brain injury survivors. Motor vehicle accident (MVA) is the highest contributor of TBI or DAI. The essence of trauma is the infliction of pain and suffering and having to bear the pain (i.e. by the TBI survivor) and the burden of having to take care and manage and rehabilitate the TBI survivor (i.e. by the TBI caregiver). Moreover many caregivers are not trained for their care giving task, thus compounding the stress of care giving and rehabilitating patients. Most research on TBI including DAI, focus on the survivors and not on the caregivers. TBI injury and its effects and impacts remain the core question of most studies, which are largely based on the quantitative approach.

    EVIDENCE ACQUISITION: Qualitative research can better assess human sufferings such as in the case of DAI trauma. While quantitative research can measure many psychometric parameters to assess some aspects of trauma conditions, qualitative research is able to fully reveal the meaning, ramification and experience of TBI trauma. Both care giving and rehabilitation are overwhelmingly demanding; hence , they may complicate the caregivers' stress. However, some positive outcomes also exist.

    RESULTS: Caregivers involved in caring and rehabilitation of TBI victims may become mentally traumatized. Posttraumatic recovery of the TBI survivor can enhance the entire family's closeness and bonding as well as improve the mental status of the caregiver.

    CONCLUSIONS: A long-term longitudinal study encompassing integrated research is needed to fully understand the traumatic experiences of caregivers. Unless research on TBI or DAI trauma is given its proper attention, the burden of trauma and injury on societies will continue to exacerbate globally.

    Matched MeSH terms: Motor Vehicles
  18. Azra MN, Ikhwanuddin M
    Saudi J Biol Sci, 2016 Mar;23(2):257-67.
    PMID: 26981008 DOI: 10.1016/j.sjbs.2015.03.011
    Study of broodstock maturation diets is important in order to increase the quality of berried females, which indirectly improve the larval quantity in the hatchery production of cultured species. This paper reviewed the studies on the maturation diets for mud crab broodstock, genus Scylla and compared independently to identify their effect on reproductive performance and larval quality. The broodstock is usually caught from the wild and held in the spawning or maturation tank for further use of hatchery seed production. Mud crab broodstock was fed either natural diet, artificial diet or mixed diet. Trash fishes were commonly used as a natural feed for mud crab broodstock; meanwhile artificial diets are from formulated fish meal and various kinds of feed. The results indicated that mud crab broodstock has a high dietary requirement for lipids, fatty acids and protein which are to be used during the maturation and breeding processes. However, the natural diet produce better larval quality compared to the artificial diet. The mixed diet is the better diet which resulted in better reproductive performances such as growth, survival, fecundity and maturation processes. This review also discusses the problems in the previous studies for the potential future research to develop very high quality and cost-effective formulated diet for the enhancement of broodstock and seed production technology. Information from this review can be useful in developing a better quality of crustacean broodstock's diet for commercial hatchery production.
    Matched MeSH terms: Motor Vehicles
  19. Jong VS, Tang FE
    Water Sci Technol, 2016;73(4):909-15.
    PMID: 26901735 DOI: 10.2166/wst.2015.563
    Individual septic tanks are the most common means of on-site sanitation in Malaysia, but they result in a significant volume of septage. A two-staged vertical flow constructed wetlands (VFCWs) system for the treatment of septage was constructed and studied in Sarawak, Malaysia. Raw septage was treated in the first stage wetlands, and the resulting percolate was fed onto the second stage wetlands for further treatment. Here, the effects of a batch loading regime on the contaminant removal efficiency at the second stage wetlands, which included palm kernel shell within their filter substrate, are presented. The batch loading regime with pond:rest (P:R) period of 1:1, 2:2 and 3:3 (day:day) was studied. The improvement of the effluent redox condition was evident with P:R = 3:3, resulting in excellent organic matters (chemical oxygen demand and biochemical oxygen demand) and nitrogen reduction. The bed operated with P:R = 1:1 experienced constant clogging, with a water layer observed on the bed surface. For the P:R = 3:3 regime, the dissolved oxygen profile was not found to decay drastically after 24 hours of ponding, suggesting that the biodegradation mainly occurred during the first day. The study results indicate that a suitable application regime with an adequate rest period is important in VFCWs to ensure efficient operation.
    Matched MeSH terms: Motor Vehicles
  20. Lim AC, Chong VC, Wong CS, Muniandy SV
    PeerJ, 2015;3:e1471.
    PMID: 26734507 DOI: 10.7717/peerj.1471
    Background. Syngnathid fishes produce three kinds of sounds, named click, growl and purr. These sounds are generated by different mechanisms to give a consistent signal pattern or signature which is believed to play a role in intraspecific and interspecific communication. Commonly known sounds are produced when the fish feeds (click, purr) or is under duress (growl). While there are more acoustic studies on seahorses, pipefishes have not received much attention. Here we document the differences in feeding click signals between three species of pipefishes and relate them to cranial morphology and kinesis, or the sound-producing mechanism. Methods. The feeding clicks of two species of freshwater pipefishes, Doryichthys martensii and Doryichthys deokhathoides and one species of estuarine pipefish, Syngnathoides biaculeatus, were recorded by a hydrophone in acoustic dampened tanks. The acoustic signals were analysed using time-scale distribution (or scalogram) based on wavelet transform. A detailed time-varying analysis of the spectral contents of the localized acoustic signal was obtained by jointly interpreting the oscillogram, scalogram and power spectrum. The heads of both Doryichthys species were prepared for microtomographical scans which were analysed using a 3D imaging software. Additionally, the cranial bones of all three species were examined using a clearing and double-staining method for histological studies. Results. The sound characteristics of the feeding click of the pipefish is species-specific, appearing to be dependent on three bones: the supraoccipital, 1st postcranial plate and 2nd postcranial plate. The sounds are generated when the head of the Dorichthyes pipefishes flexes backward during the feeding strike, as the supraoccipital slides backwards, striking and pushing the 1st postcranial plate against (and striking) the 2nd postcranial plate. In the Syngnathoides pipefish, in the absence of the 1st postcranial plate, the supraoccipital rubs against the 2nd postcranial plate twice as it is pulled backward and released on the return. Cranial morphology and kinesis produce acoustic signals consistent with the bone strikes that produce sharp energy spikes (discrete or merged), or stridulations between bones that produce repeated or multimodal sinusoidal waveforms. Discussion. The variable structure of the sound-producing mechanism explains the unique acoustic signatures of the three species of pipefish. The differences in cranial bone morphology, cranial kinesis and acoustic signatures among pipefishes (and seahorses) could be attributed to independent evolution within the Syngnathidae, which warrants further investigation.
    Matched MeSH terms: Motor Vehicles
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