Hearing aids (HA) is the primary medical intervention aimed to reduce hearing handicap. This study assessed the cost-effectiveness of HA for older adults who were volunteered to be screened for hearing loss in a community-based mobile hearing clinic (MHC).Participants with (1) at least moderate hearing loss (≥40 dB HL) in at least one ear, (2) no prior usage of HA, (3) no ear related medical complications, and (4) had a Mini-Mental State Examination score ≥ 18 were eligible for this study. Using a delayed-start study design, participants were randomized into the immediate-start (Fitted) group where HA was fitted immediately or the delayed-start (Not Fitted) group where HA fitting was delayed for three months. Cost utility analysis was used to compare the cost-effectiveness of being fitted with HA combined with short-term, aural rehabilitation with the routine care group who were not fitted with HA. Incremental cost effectiveness ration (ICER) was computed. Health Utility Index (HUI-3) was used to measure utility gain, a component required to derive the quality adjusted life years (QALY). Total costs included direct healthcare costs, direct non-healthcare costs and indirect costs (productivity loss of participant and caregiver). Demographic data was collected during the index visit to MHC. Cost and utility data were collected three months after index visit and projected to five years.There were 264 participants in the Fitted group and 163 participants in the Not Fitted group. No between-group differences in age, gender, ethnicity, housing type and degree of hearing loss were observed at baseline. At 3 months, HA fitting led to a mean utility increase of 0.12 and an ICER gain of S$42,790/QALY . At five years, the ICER was estimated to be at S$11,964/QALY  assuming 70% of the participants continued using the HA. As fewer individuals continued using their fitted HA, the ICER increased.HA fitting can be cost-effective and could improve the quality of life of hearing-impaired older individuals within a brief period of device fitting. Long term cost-effectiveness of HA fitting is dependent on its continued usage.The online version contains supplementary material available at 10.1186/s12913-020-05977-x. As we age, our sensory abilities may decline . PresbycSingapore, a small country with a population size of about 5.6 million, has one of the fastest ageing population in the world. By 2035, it is projected that 32% of the population will be aged 65 years and above . In 2010Hearing loss has profound negative impact on the individual, significant others, and society. It is associated with multiple negative health outcomes such as functional and cognitive impairment , 12, comThe most common clinical intervention for people with age-related hearing loss is hearing aids (HA). These medical devices do not restore hearing; however, they make sounds more audible through electroacoustic amplifications. The goal of HA is to reduce hearing handicap and promote a more active and engaged lifestyle which as a result, improves general quality of life, interpersonal relationships, emotional and physical functioning in adults with mild to moderate hearing loss –24. FollCost utility analysis (CUA) is the recommended method used to perform economic evaluations. It compares the health benefit, typically expressed as the patient-reported utility, quality adjusted life years (QALY), to the cost of an intervention. This cost utility ratio assesses interventions by what health related improvements can be achieved per unit cost. Information regarding cost effectiveness of HA is scarce. A recent review of seven studies that performed economic evaluation of HA  found that there was high variability in the cost-effectiveness of the HA device ranging from USD 9702 to USD 721,942/QALY . Only thParticipants were residents who volunteered to be screened for hearing loss at a community-based mobile hearing clinic (MHC) from December 2015 to June 2017. They are likely to be those who suspect that they may have some hearing issue or want to assure themselves that they are fine. Participants who were found to have (1) at least moderate hearing loss (≥40 dB HL) in at least one ear, (2) no prior usage of HA in the last ten years and (3) free from ear related medical complications and (4) had a Mini-Mental State Examination (MMSE) score ≥ 18 were eligible for this study. Eligible participants were then offered the HA services in the MHC.The MHC is a community outreach program staffed by a team of audiologists, research assistants and trained audio technicians that offers hearing diagnostic tests, referrals general practitioners (GP) or ENT specialist clinic, HA fitting and short-term post-fitting audiological rehabilitation services. Sited in a purpose-built truck chassis, the MHC has been specially retrofitted with two sound-treated rooms and audiological equipment for the delivery of hearing tests, HA fitting and aural rehabilitation. During the study, the MHC was parked in 38 community centres or near-by neighbourhoods to provide hearing test and HA fitting services to residents.Research assistants and audiologists screened participants for hearing loss through a series of steps. Otoscopy examination was performed by research assistants to inspect for outer ear conditions such as impacted ear cerumen, ear infection, perforated tympanic membrane and presence of any foreign body in the ear canal . A trainParticipants with impacted ear cerumen or ear related medical complication were referred to general practitioners or public hospitals and were excluded from the study. Participants with MMSE scores < 18 or those with prior usage of HA in the last 10 years were also excluded from the study.After hearing screening, eligible participants who were keen to adopt HA were scheduled for HA selection based on treatment groups they were randomly assigned to (please see study design). During the HA selection session, audiologist discussed with study participant his/her hearing test result, importance, benefits, limitations, and the different types of HA. HA use in both ears were encouraged for participants with binaural hearing loss. Upon decision to adopt HA use and participate in the study, enrolled study participants were then scheduled for HA fitting within the following two weeks.HA fitting was conducted by an audiologist in accordance to the American Speech Language Hearing Association (ASHA) HA fitting guidelines . PhysicaAural rehabilitation was scheduled two weeks post HA fitting, in a small group setting at the community centre. The aim of the rehabilitation was to re-emphasize use, care, and maintenance of HA, re-learn hearing with the use of the device, practise communication skills and repair strategies and clarify/discuss any issues participants were having with regards to HA use. Two additional rehabilitation sessions were given to participants at one- and three-months post HA fitting. Participants that required more sessions could make an appointment at the MHC.To establish effectiveness of the HA intervention, suitable controls were required. Residents with hearing loss and refused HA may not be viable controls as there may be systematic differences (e.g. socioeconomic differences) between those who took up the HA and those who did not. An ideal control group would be eligible participants for whom we can delay the HA intervention and rehabilitation.A prospective delayed-start randomized design was used for this study . ParticiParticipant’s demographic, employment status and occupation information were collected during the participant’s first visit to the MHC. Outcomes were collected for both Fitted and Not Fitted groups at baseline and three months Fig. . For thiUsing the RANDBETWEEN function in Microsoft Excel Version 2004, community centres with random number “0” were assigned to the immediate treatment group, while the community centres with random number “1” were allocated to the delayed treatment group. The MHC was assigned to each community centre on a weekly basis.n = 240) and Not Fitted (n = 240) groups.To detect a difference in health-related quality of life (HRQoL) as low as 0.06  with an Cost utility analysis (CUA) was used to compare the cost-effectiveness of being fitted with a HA combined with short-term post audiological rehabilitation (Fitted) with the control group who received no treatment (Not Fitted). Two outcomes were measured for this study – 1) patient-reported utility, using the quality adjusted life years (QALYs) metric and (2) total costs. QALY is a measure of health as a combination of duration of life and health related quality of life (HRQoL). Health utility index (HUI-3) is a psychometric questionnaire that this study’s participants completed in order to measure change in HRQoL. The HUI-3 comprises of eight attributes – vision, hearing, speech, ambulation, dexterity, emotion, cognition, and pain. Each attribute has about 5 to 6 levels of ability or disability. A combination of levels across the eight attributes constitutes as a health state. The health state is converted into a utility score of 0 (dead) to 1 . Due to the inclusion criteria of no HA usage prior to study enrolment and upon advice from the tool developers, the HUI-3 was modified to exclude questions regarding HA use . Direct healthcare costs were defined as the expenditures incurred in the healthcare management system for the diagnosis, treatment, and management of hearing loss. In this study, the direct healthcare costs included:All expenditures incurred at the MHC due to hearing loss andAll healthcare expenditures incurred due to visits to any other healthcare institutions  due to hearing loss, three months after the index visit to the MHC.Costs were estimated from a societal perspective and included direct healthcare, direct non-healthcare, and indirect costs Fig. . Direct Expenditure incurred at the MHC included consultation-related  and device-related  costs. Using a cost questionnaire developed by the study team,  and monetised using the human capital approach . The met. Costs were expressed as mean costs (standard deviation) per patient in 2017 Singapore dollar.Descriptive analysis was used to compare the baseline characteristics of Fitted and Not Fitted Groups. Costs for Fitted group  were compared with Not Fitted group  Fig. . Costs wThe incremental cost effectiveness ratio (ICER), otherwise known as cost per QALY, was the primary outcome measure of this CUA. ICER was computed by taking the difference between costs of the groups divided by the difference in QALY produced by the two groups. Health interventions with a cost per QALY of < 50,000 USD/QALY is cost effective . As cost25, 50 and 70% of the participants continued using the HA for five yearsUtility gained at three months was constant for five yearsHealthcare utilization and productivity losses incurred at three months for both groups was projected for five years with a 5% discount rate.ICER was computed based on the primary data and then extrapolated to five years with the following assumptions: for point estimates of ICER, bootstrapping was performed that generated 1000 predicted values for the cost-utility ratio. Similar scenarios were projected with 50 and 25% of participants using HA for 5 years. The computation of costs and QALY were done using Microsoft Excel Version 2004. All other analysis was conducted using R statistical software version 3.4.(Table ). Approximately 62% of participants were retired, 34% were employed and 4% were unemployed in both groups. The employment status of the caregiver are as follows: 49% employed; 30% were retired; 14.1% were unemployed, 3.9% were foreign domestic workers (FDWs) and 3% others, with no differences in the distribution between the two groups.A summary of population profile can be found in Table Table . Approxi(Table ). Direct non-healthcare cost which was mainly transportation costs amounted to an average of $37.95. For the Fitted group, 39.3% of participants were employed and were absent from work for at least an average of 4.4 (SD:2.0) days due to visits to the MHC. Less than one-third of these participants were accompanied by a caregiver during the visit to MHC (n = 74). Only 37 caregivers were employed, of which nearly 50% had taken time from work to accompany the participant to the MHC and were absent from work for an average of 4.9 (SD:2.1) days. This resulted in a total productivity loss of participant and caregiver of $168.90.At the MHC, the direct costs incurred for the Fitted group was SGD $4809.50 which includes consultation and device costs Table . Direct For additional healthcare utilization due to hearing loss that occurred during the three months after index visit to the MHC, the total costs were minimal. Less than 20% of the participants in both groups had at least one visit to any healthcare institutions due to hearing loss in the three months after index visit to MHC. Of which, seven patients were absent from work for approximately 0.5 days for each group. Only seven caregivers in Fitted and nine caregivers in Not Fitted group were present during these visits with only less than half day of leave. The total costs for both groups amounted to less than $35 .HUI-3 scores computed for all timepoints is provided in additional file This prospective study indicates that moderately hearing-impaired individuals achieved significantly improved HRQoL within a brief period following HA fitting. The ICER determined by this study was within the threshold of cost-effectiveness for older adults being fitted with HA coupled with short-term audiological rehabilitation at the community-based MHC in Singapore. However, as the proportion of participants who continued with the use of HA over the projected 5 years decreased, the ICER increased. Most of the participants in both Fitted and Not Fitted group were either retired or unemployed. Considering the age distribution of this population, this finding seems reasonable. Healthcare utilization and productivity loss (participant and caregiver) due to hearing loss were low for both groups. Therefore, being fitted with HA would have minimal impact on productivity gain in this population.The limited studies that assessed the cost-effectiveness of HA compared to no HA resulted in a wide range of ICERs  . These sBeing fitted with HA not only reduces hearing handicap but also improves the emotional, social and physical function of adults with hearing loss –24. DespThis is the first study to have evaluated the economic costs of HA in the context of a community-based MHC in Singapore. Individuals who refused to take up the HA may not be suitable as controls as there could be systematic differences such as socioeconomic status between those who took up and did not take up HA. The delayed start study design facilitated selection of suitable controls that were similar in characteristics to participants who were willing to take up the HA by delaying treatment of HA fitting and rehabilitation for three months so study outcomes can be collected. However, the sample size for the Not Fitted group was lower than what was computed resulting in a study power of 77%. Despite the smaller sample size, there were no differences in the profile of participants in Fitted and Not Fitted group.One of the main limitations of this study was that this study was based on volunteers who had come to the MHC for screening and may not represent the general populations. Subjects that came for screening were mostly retied which may have allowed them to visit the MHC. Productivity loss computed from study population may also not be generalizable to adults who are still in the working force. Participants were also asked to recall the number of visits to the clinic due to hearing loss, transportation costs and number of days absent from work (for both participant and caregiver) in the last three months after the first visit to the MHC. This could have resulted in underestimated costs and healthcare utilization due to recall bias. Short-term economic costs of fitting older adults with moderate to severe hearing loss with HA at the MHC as well as healthcare utilization at other primary care or specialist clinics were considered for this study. It assumes all participants fitted with HA were satisfied users and did not account for all other possible transitions that may occur for individuals with hearing loss such as satisfied HA-users and dissatisfied HA-users, progression of hearing loss or even frequency of HA use. Satisfied HA-users may use HA regularly and be compliant with routine check-ups while the dissatisfied HA-users may revisit audiologists to resolve issues regarding use of HA, which may result in different healthcare costs . There aWith earlier screening of hearing loss in the adult population, future studies can explore ways to obtain a more representative study population of adults to investigate productivity gains in greater detail and over a longer period. Future research in Singapore can explore the potential use of dynamic patient flow models to simulate the various transition states for hearing loss and ongoing decisions problems in HA use to accurately evaluate the cost effectiveness of HA use for older adults with HI , 30, 51.This study suggests that fitting moderately impaired older adults with HA at a community-based MHC was cost-effective. Strategies such as promoting management of hearing loss at an earlier age, timely fitting and monitoring continued use of HA will be beneficial to both the individual as well as cost effectiveness of the device.Additional file 1 Table S1. Scoring Methodology for modified HUI-3. Table S2. Breakdown of Costs incurred at primary care or ENT specialist clinics. Table S3. Proportion of continued HA uptake after 1 year. Fig. S1. HUI-3 scores at all time-points.Additional file 2. Direct and Indirect cost questionnaire.


Recently, trends in TC translation speed and the likelihood of stalled TCs such as Harvey have received significant attention, but findings have remained inconclusive. Here, we examine how the June-September steering wind and translation speed of landfalling Texas TCs change in the future under anthropogenic climate change. Using several large-ensemble/multi-model datasets, we find pronounced regional variations in the meridional steering wind response over North America, but―consistently across models―stronger June-September-averaged northward steering winds over Texas. A cluster analysis of daily wind patterns shows more frequent circulation regimes that steer landfalling TCs northward in the future. Downscaling experiments show a 10-percentage-point shift from the slow-moving to the fast-moving end of the translation-speed distribution in the future. Together, these analyses indicate increases in the likelihood of faster-moving landfalling Texas TCs in the late 21 How climate change affects the translation speed of tropical cyclones has been the subject of intensive debate. Here, the authors use models to show that future regional changes in the steering winds lead to faster-moving tropical cyclones as they make landfall in Texas. The critical measures needed to strengthen the resiliency of the Texas coastline, and in particular the Houston-Galveston area, against future TCs require an understanding of the region’s past TCs and their potential changes in the future in a changing climate.Since the beginning of the 21st century, Texas has experienced a number of devastating TCs; the three costliest ones are Tropical Storm Allison , Hurricane Ike , and Hurricane Harvey , which all caused severe damage around Greater Houston, the most populous and industrialized region along the Texas coast. Harvey, Ike, and Allison, with estimated damage of $125B, $34.8B, and $11.8B, are respectively the 2nd, 7th, and 16th costliest TCs affecting the mainland of the United States (US), after accounting for inflation6, while Ike caused damage due to strong winds and a record-breaking storm surge8. Several factors  influence the characteristics of the damage from a TC, and various consequences of climate change , increased atmospheric moisture, changes in large-scale circulation) influence these factors12.The damage from the aforementioned TCs had different characteristics: Harvey and Allison caused flood damage due to record-breaking rainfall16. More recently, a number of studies have investigated how the translation speed of TCs at the global or basin-wide scale might have changed in the past few decades, or are projected to change in the future under anthropogenic climate change; however, their findings have remained inconclusive24.Changes in TCs’ characteristics such as frequency and intensity have been extensively studied in the past−1) increases by ~6% while that of slow-moving TCs (speed ≤5 km h−1) decreases by ~4%, indicating a 10-percentage-point shift from the slow-moving end to the fast-moving end of the translation-speed distribution. Our results do not show any evidence for an increase in the likelihood of slow-moving landfalling Texas TCs in the late 21st century under climate change; on the contrary, our results indicate a higher probability of fast-moving TCs.The focus of this paper is on a specific question: how will climate change influence the movement of future landfalling Texas TCs, and specifically their translation speed? To answer this question, we use several large-ensemble/multi-model datasets and clustering and downscaling techniques. Examining changes in the June to September steering winds and frequency/pattern of clustered daily steering winds shows an increase in the northward meridional steering winds over Texas in the period of 2074–2100 compared to 1979–2005 under the RCP8.5 emission scenario. We suggest that this regionally robust change in atmospheric circulation is associated with an intensifying and west-ward shifting Atlantic subtropical high and a weakening American monsoon. Consistent with these changes in steering winds, downscaling experiments show that in the future, the relative frequency of fast-moving TCs  and upper-level 200 mb (20%) winds). Ike, however, was a fast-moving TC that crossed Texas in less than one day. Around the time of Ike’s landfall, an anomalous high-pressure system was present over eastern US and an anomalous low-pressure system was present over mid-western US, which together resulted in strong anomalous northward steering winds, leading to Ike’s fast northward translation speed. These examples show, to the leading order, the effects of the large-scale circulation on the movement of the three most-devastating Texas TCs in the 21st century.Figure 26. To reduce these uncertainties, we use three sets of large-ensemble simulations with 20, 40, and 100 members, as well as single-member simulations from 14 Coupled Model Intercomparison Project Phase 5 (CMIP5) models  part of a dipolar meridional wind pattern with a southward component west of ~100°W; see Fig. Consistently across all models, the steering eastward winds are projected to decline between 30°N and 50°N, associated with the poleward shift of the midlatitude westerlies23 and Zhang et al.24 for the implications of these changes). The northward steering wind response adds to the natural tendency of TCs to move poleward due to beta advection29 and is robust from June to September , which predominantly results from the enhanced land-ocean thermal contrast31. Furthermore, the increase in the upper-level northward wind over Texas is consistent with the weakening of the North American monsoon33 , which is due to increases in static stability with sea-surface warming32. These changes in the Atlantic subtropical high and American monsoon constructively influence the low- and upper-level meridional winds over Texas, leading to a remarkably robust increase in the northward steering winds.Recently, Wills et al.34, we apply the SOM analysis to the data of current and future climates combined together (see Methods section). Supplementary Fig. In the above analysis, we discussed changes in the June to September and monthly-mean steering winds. Below, we will examine how climate change affects the daily steering wind patterns over southern US by applying a self-organizing map (SOM) cluster analysis to the LENS daily steering wind vectors  in the current 1979–2005) and future 2074–2100) climates (see Methods section). We focus on LENS, which reproduces the 1979–2005 daily steering wind regimes in the NCEP-DOE reanalysis fairly well . These experiments account for not only the effects of changes in the steering winds and TC frequency, but also changes in other environmental variables including the potential intensity (PI), mid- to low-level moisture, and low-level vorticity. The CHAZ model is downscaled from six CMIP5 models (see Methods section). Statistics of the synthetic TCs generated by CHAZ at the global and basin-wide scales are described in Lee et al.35. Here we use only a subset of storms that pass through an area within 300 km from Houston at the historical  and late 21st century  periods.Our interpretation of how changes in the daily steering wind patterns affect the movement of future TCs involves the assumption that TCs approach the Texas coastline with the same probability across different clusters. However, both the TC probability and the occurrence of a given cluster are connected to the large-scale atmospheric circulation, in particular the subtropical circulation, which is responsible for moving TCs from their genesis region  toward the Texas coast. Therefore, next we examine changes in the translation speed of landfalling Texas TCs in synthetic TCs generated by a downscaling model, the Columbia TC HAZard model  while overestimating the probability of the fast-moving ones (translation speed ≥20 km h−1). Thus, we also analyze data in which this bias has been corrected using two different methods (see below). The probability density function (PDF) in the translation speeds shifts under RCP8.5 toward higher speeds  from six CMIP5 models.Our results show no evidence for an increase in the probability of slow-moving landfalling Texas TCs by the end of the 21st century. Instead, we find a robust projected increase in the northward steering winds over Texas, which could lead to an increase in the frequency of fast-moving landfalling TCs. Indeed, the downscaling experiments show a decrease in the likelihood of slow-moving TCs making landfall around Houston, and an increase in the likelihood of the fast-moving ones. The aforementioned changes in the steering winds over Texas appear to be associated with changes in the Atlantic subtropical high and American monsoon. Our results highlight the importance of conducting regional analyses to investigate the effect of climate change on the movement of future TCs, as there are prominent regional variations in the steering winds’ future changes. Note that while we focus on Texas in this paper, our multi-model, multi-faceted approach can be readily applied to other regions in future work.17 has reported a global slowdown of TCs in the period of 1949–2016, including by 16% over land areas affected by the North Atlantic TCs. However, the analysis of Kossin17  differs in region and period from our results; thus a direct comparison is not valid. Furthermore, some recent studies23 have challenged the findings of Kossin17. In particular, Yamaguchi et al.23 showed that large-ensemble, high-resolution simulations using an atmospheric general circulation model (AGMC) do not support a slowdown of northern hemisphere TCs from 1951 to 2011, and attributed the slowdown reported in Kossin17 to inhomogeneities of the observational data in the pre- and post-satellite eras.We emphasize that the focus of our study is on potential changes in the movement of landfalling Texas TCs by the end of the 21st century compared to the late 20th century due to anthropogenic climate forcing. This emphasis should be kept in mind when comparing our conclusions with those of other recent studies. For example, Kossin23 and Zhang et al.24 have conducted AGCM simulations with +4 K warmer global SST and compared the TC translation speeds in the period of 2051–2110 versus 1951–2011. Both studies found a decrease in the average TC translation speed at higher latitudes in the future , Yamaguchi et al.23, as discussed in detail in their paper, found, overall, an increase in the annual-mean global TC translation speed, including a statistically significant increase from 22.1 km h−1 to 22.6 km h−1 in the North Atlantic basin. While the conclusion of their work appears to be similar to ours, the underlying reasons are entirely different, because of our focus on the Texas coastline (low latitudes) and their focus on hemispheric and basin-wide changes (low and high latitudes). We found an increase in the likelihood of fast-moving landfalling Texas TCs due to the increase in northward meridional steering winds over the northern Gulf region and Texas. Thus, our work and that of Yamaguchi et al.23 and Zhang et al.24 answer different, although complementary, questions.To examine the effect of climate change, Yamaguchi et al.18 have performed pseudo-global warming simulations using the Weather Research and Forecasting (WRF) model and examined how the movement of eastern and southeastern US TCs might change under RCP8.5 by the end of the 21st century. Among the 22 TCs they examined that had small track changes between the current and future simulations, Ike was the only Texas hurricane  with statistically significant change in its translation speed, which decreased from 8.1 m s−1 to 6.7 m s−1. Our study and that of Gutmann et al.18 focus on similar periods and region; however, there are major differences in our methodologies. In our multi-model, multi-faceted approach, the conclusions are based on consistent statistical changes of steering winds and synthetic TCs, while Gutmann et al.18 drew their conclusions from changes in the single-model simulations of a few historical TCs in pseudo-global warming experiments. Thus, changes in the landfalling TC frequency and impacting angle are not considered in their study. Furthermore, we focus on the movement and translation speed around the time of landfall, while Gutmann et al.18 considered the average translation speed over the entire lifetime of the storms, e.g., in the case of Ike, from the Caribbean Sea to northern US. Further investigations are needed to fully understand the differences and reconcile the conflicting conclusions between our work and that of Gutmann et al.18.Gutmann et al.6. However, the increased possibility of fast-moving landfalling Texas TCs in the future does not necessarily suggest a reduced risk to human life, infrastructure, and ecosystems. For example, the financial damage from Hurricane Ike, a fast-moving hurricane, was comparable to that of the slow-moving Hurricane Harvey. However, as mentioned earlier, the damages were due to differing factors: intense rainfall (which led to extensive flooding) in the case of Harvey, and storm surge-induced flooding and wind gust in the case of Ike. Understanding the main driver(s) of damage by future TCs in each region is crucial for adaptation and mitigation efforts, as different drivers require different―and often costly and controversial―protective measures and strategies 39.Hurricane Harvey’s slow movement and stall over Texas was a major contributor to its extreme rainfall and the resulting flooding40 should also be considered. Some recent studies have quantified the influence of climate change on Hurricane Harvey’s and future Texas TCs’ rainfall41 as well as future TC-induced flooding42. Our work suggests that further investigation, particularly aimed at disentangling the contributions from changes in dynamics  and thermodynamics (temperature) are needed to better understand and constrain the impact of climate change on the risk of TCs making landfall in Texas. Finally, in this paper, as in most other studies, we focus on changes in the late 21st century under the high-emission scenario, RCP8.5 . However, to better inform the adaptation and mitigation efforts, mainly about the time of emergence and the magnitude of these changes in TC movement, similar analyses for the mid-21st century and under other emission scenarios such as RCP4.5  should be conducted in future work.The damage from a TC depends on many factors, and to fully assess the risk of future TCs, in addition to changes in their movement, changes in TC size and intensity, as well as sea level, SST, air moisture content, other environmental factors, and even urbanization43. The data are plotted at the native resolution of 0.5° × 0.5° in Fig. Cumulative precipitation during each storm is calculated for the specified time period using the National Oceanic and Atmospheric Administration (NOAA) Climate Prediction Center (CPC) global unified gauge-based analysis of daily precipitation44, which contains interpolated ~3-hourly data for storm positions. Data are overlaid using the Climate Data Toolbox for MATLAB45.The TC track data are obtained from the International Best Track Archive for Climate Stewardship (IBTrACS), version 4u and v) and Z500 from NCEP-DOE reanalysis 2 dataset46. In Fig. 25 as the weighted average between winds at 850 mb and 200 mb:We use 1979–2018 daily averaged zonal and meridional winds  Community Earth System Model (CESM) Large Ensemble Community Project (LENS)47, the Max Planck Institute for Meteorology (MPI) Grand Ensemble (MPI-GE)48, and the Geophysical Fluid Dynamics Laboratory (GFDL) Climate Model version 3 (CM3) Large Ensemble (GFDL-LE)49. We also use daily averaged u and v from LENS and GFDL-LE.We use monthly averaged These datasets contain data from fully coupled atmosphere-land-ocean-ice simulations of the period 1920–2005, based on the historical radiative forcing, and the period 2006–2100, where the forcing is chosen based on the high-emission scenario RCP8.5. For each period, an ensemble with 20 (GFDL-LE), 40 (LENS), or 100 (MPI-GE) members are simulated by starting from initial conditions that differ in small random perturbations. The LENS, MPI-GE, and GFDL-LE models have horizontal resolutions of approximately 1°, 1.8°, and 2°, respectively.To compute mean changes in large-scale circulation from the large-ensemble and CMIP5 datasets Fig. –9, we anu, v, and Z500 from 14 models in Phase 5 of the Coupled Model Intercomparison Project (CMIP5)50; see Supplementary Table We use monthly averaged 51, which is an artificial neural network that has been extensively used to classify climate data57. To conduct the cluster analysis, we compute vectors consisting of the zonal and meridional components of the daily steering winds ds (Eqs. ) for eacIn order to find the uncertainties of the frequencies, we perform 50 repetitions of SOM clustering, each time using one fifth of the total available data chosen randomly. Pattern correlation is used to find the correspondence between the cluster centers obtained each time and those obtained from the entire dataset. In Supplementary Figs. We focus on the LENS dataset, which provides daily wind data for a 40-member ensemble for each period, and in the period of 1979–2005, reproduces the June–September steering wind clusters of reanalysis data fairly well ; using 12 clusters (SOM size = 3 × 4) leads to the same conclusion.54, we apply the cluster analysis on a dataset consisting of both current and future climates. Here, we follow the framework of Gervais et al.34. For each cluster i, we define the frequency i  HAZard model, is used for generating synthetic storms in the historical period  and the late 21st century under RCP8.5 . Lee et al.59. The track model then moves seeds forward by advection of the environmental steering wind 63, deep-layer (850 mb to 250 mb) vertical wind shear, the moisture variables – column integral relative humidity (CRH) or saturation deficit (SD), the absolute vorticity at 850 mb, and the steering flow. SD is the difference between the column integrated water vapor and the same quantity at saturation, and the CRH is their ratio. Both are calculated following Bretherton et al.64.The CHAZ model consists of three separate models: genesis, track, and intensity. The genesis model seeds the domain with weak vortices using a seeding rate that depends on environmental conditions through a TC genesis index (TCGI)nd (Eqs. –2)) plu) plu59. 35 that affect Texas. In Lee et al.35, the CHAZ model is downscaled from monthly averaged data of six CMIP5 models; see Supplementary Table 35, the future projections of the annual frequency of TCs globally and in the North Atlantic region are sensitive to the choice of CRH and SD in TCGI. Consequently, there is a large uncertainty in assessing the frequency of TCs affecting Texas in future climate. However, Lee et al.35 noticed that the projected changes in the forward speed are not sensitive to the annual TC frequency. Therefore, as our focus is on the changes in the steering winds and the relative probability distribution of the forward speed, we use all the Texas storms from both CRH and SD experiments described in Lee et al.35. We refer to synthetic storms from the historical period (1981–2005) as ‘HIST’ while those from the late 21st century (2071–2099) as ‘RCP8.5’.In this study, we use a subset of synthetic storms from Lee et al.44. We use the 6-hourly storm location (in longitude and latitude) and maximum wind speed from 1981 to 2018. As noted in the Results Section, CHAZ captures the climatology of the observed forward speed of Texas storms relatively well (Fig. 65. When doing so, we should examine whether our results and conclusions are sensitive to the bias correction approach. Thus, we conduct additional sets of analyses using bias-corrected data with two distribution mapping approaches applied.The CHAZ results from the HIST period are compared to the observations from IBTrACS version 466, which allows the CHAZ’s distribution to match the entire observed distribution. We derive the correction factors using CHAZ HIST simulations and then apply the same corrections to simulations for RCP8.5. Supplementary Figure In the first approach, we assume that the relative probability distributions of the forward speed and direction are Gaussian, and we correct the location and scale parameters of the modeled distribution. In other words, the corrected distribution has the same mean and standard deviation as the observed one. In the second approach, we use the quantile-matching techniqueSupplementary InformationPeer Review FileDescription of Additional Supplementary FilesSupplementary Data 1Supplementary Data 2


Given the concern regarding increased hearing loss in young people who use personal listening devices (PLDs), the present study analyzes the experience of PLDs among college students to identify their knowledge of and attitude toward hearing conservation. It also explains their relationship between knowledge of hearing loss and attitude-related hearing conservation as a questionnaire response using a regression model. A total of 1009 Korean college students responded to an online questionnaire. As a survey tool, the Personal Listening Device and Hearing Questionnaire was adapted as a Korean version with 78 modified items under 9 categories. Using principal component analysis, specific factors were extracted, and their relationships and paths were confirmed using multiple regression analysis. The results of the knowledge category of the questionnaire indicate that most respondents knew how to maintain healthy hearing and understood the signs of hearing loss. Regardless, many college students habitually use PLDs at high levels in noisy environments; they do not recognize how to prevent hearing loss. Even though they continue their current use pattern for PLDs, they also had a positive attitude toward receiving more information about hearing conservation. According to the regression model, the students’ self-reported hearing deficits were due to the volume rather than the frequent use. Interestingly, knowledge about hearing loss may encourage students to develop a positive attitude toward reasonable restriction of PLD use. When PLD users have detailed knowledge about the hearing loss provided by professionals, we believe that most will avoid serious hearing problems and its risks and maintain a judicious attitude toward their own conservation. Contemporary researchers have offered evidence of hearing loss from exposure to loud recreational noise by focusing on groups of choristers , symphonAlthough a typical method used in previous PLD studies was to measure PLL and/or maximum output levels of commercially available PLDs, it is risky to infer hearing loss only induced from their use . When weBased on World Health Organization (WHO) guidelines , the oveRQ1. Which behavior involved in using PLDs might lead to a self-reported and experienced hearing problem?RQ2. Does knowledge of hearing loss among PLD users influence their attitude toward hearing conservation?In this light, the purpose of the present study is to analyze the experience of using PLDs among Korean college students with a large sample size. A second purpose of this study is identifying their knowledge and their attitudes toward hearing conservation. Finally, a third purpose of the present study is to offer a framework for seeking and processing hearing problems and conservation  that addWe believe that the results of the current study can provide new insight into the ongoing use of PLDs among college students and motivate educational institutions to establish appropriate hearing conservation guidelines.This study was divided into two phases. In the first phase, we collected data using a questionnaire to analyze PLD usage and opinions related to hearing conservation in college students. In the second phase, we investigated certain relationships found in the data by using hypothesis testing and statistical validation.The survey instrument was the Personal Listening Device and Hearing Questionnaire (PLDHQ) that Danhauer et al. developed . We adapApart from the participants’ demographic statistics, the PLDHQ-K consisted of 9 categories: (1) knowledge about hearing loss and hearing conservation, (2) self-evaluation for hearing status and the experience of noise exposure, (3) PLD preference, (4) use pattern for PLDs, (5) reasons for using PLDs, (6) hearing effect of PLD use, (7) opinion on PLD use, (8) knowledge and attitude toward regulations, and (9) preference for education. The final item was intended to be a validity check; the participants were asked whether they had given generally conscientious responses to the questionnaire.As the target population, we recruited Koreans, primarily in their 20s and 30s, who currently attended college in South Korea. The online survey directly contacted this population by placing advertisements on social networking sites, such as Facebook and Instagram, during spring term 2018. Participants could access the PLDHQ-K, and the advertisements offered exposure to the population 56,506 times (the response rate was 1.79%). A total of 1009 participants were asked to volunteer to complete the online version of the questionnaire. The questionnaire took into consideration the regional distribution of Korean college students in seven major provinces  ; 96.8% oParticipants’ responses to the 78 items were tallied using Survey Monkey, which automatically calculates with high accuracy the percentage answering in each category for each item. The analyzed data were classified into similar topics and are categorized here in To observe certain relationships closely in this large data set, we formulated two hypotheses for the current study.Hypothesis 1 (H-1):Of the various behaviors of PLD usage, two chronic factors, e.g., volume level and usage frequency, may negatively affect users’ self-reported and experienced hearing problems.Hypothesis 2 (H-2):Our respondents’ knowledge of hearing loss helps determine their attitudes toward hearing conservation in either a positive or a negative way.p < 0.05.To test our research hypotheses, 78 items of the PLDHQ-K were analyzed using principal component analysis (PCA) with varimax rotation as the first step. Thirteen items related to 3 factors  were extracted in H-1, while another 13 items related to 4 factors (knowledge of hearing loss and 3 kinds of attitude) were tied in H-2. The selection criteria for each factor were the Kaiser’s rules, which select the factors that have eigenvalues greater than 1.0. Then, several cause-effect relationships of the items for each hypothesis were significantly explained using multiple regression analysis. All analyses were conducted for a statistical level of An online survey was employed to analyze the experience of using a PLD for 1009 Korean college student respondents to determine the level of their knowledge and their attitude toward hearing conservation.In terms of self-evaluated hearing condition, 76.1% of the respondents evaluated themselves as having good hearing (Q17) and 53.5% reported having no difficulty in hearing (Q35). Also, our respondents seemed generous about rating their own hearing condition. This result is similar to the result of the PLDHQ, with only 12% of respondents having experienced hearing difficulty . NeverthFor experience of noise exposure, approximately 77.2% of the respondents always/frequently/sometimes were in a noisy setting (Q5). Consistent with our expectations, many college students are susceptible to environmental noise, but ironically PLD users tend to set their device volume higher in environments where there is background noise ; consequOf the 1009 respondents, 72.2% reported that hazardous noise could cause secondary hearing loss for those who already had a hearing loss (Q6). Of these respondents, 66.2% knew that the hearing loss might be preventable (Q8). This response means that many college students do understand that high levels of noise can cause damage and that it is possible to prevent noise-induced hearing loss. Similarly, 74% and 82.3% of U.S. college students responded to the same questions, respectively, in the PLDHQ . NeverthMost of the college students were aware of the symptoms related to overexposure to hazardous noise. In detail, about 80% of the respondents agreed that increasing the volume of television (TV) or a radio was a sign of hearing loss (Q15); 75% also knew that experiencing tinnitus was possible after exposure to high levels of noise Q9). However, symptoms, such as “asking to repeat what it was” (Q11) and “speech seems to be heard as a muffled or mumbled sound” (Q13) were less familiar to these respondents. Interestingly, a regional difference from previous studies was found for how to recognize the signs of hearing loss. Two-thirds of U.S. college students . However, while 6The preference for PLD uses dealt with such as penetration rate or type of PLDs. More specifically, almost all the respondents had used PLDs , and most of their friends also had used them . Reflecting the current high distribution rates of smartphones in Korea , 93.8% uHere, an important, but expected, finding was that most of the college students listened to their PLDs using an earphone of the earbud type . When combining PLDs with earbuds, the average attenuation of background noise was the lowest of other types of earphones  and userOf the college student respondents, 77% had used a PLD for more than two years (Q34). Although about half of the respondents used their PLDs all days in the week (Q37), their use time per session was not long at 0.5 to 1 h (34.9%) and 1 to 2 h . Also, the average use time of the PLDs in a day was rather widely distributed, ranging from 0.5 to 4 h (Q39). Regarding frequency of PLD use for more than 4 h in one particular place during a year, 1 to 3 times was the highest response  and followed 21 or more times . Interestingly, these results showed certainly divided responses in terms of using time in one session. In short, Korean college students did not seem to use PLDs for enough extended time to damage hearing, but they did listen longer than participants in the Kaplan-Neeman et al. (2017) study, which reported less than 30% using a PLD for 0.5 to 1 h in a single day . HoweverThe response for Q41, which asked about preferred volume was widely distributed at volume steps 4 to 8, although volume step 6 was the most frequent response (19.1%). Similarly, 52% of the respondents thought their volume was only ‘medium’ (Q42). This was not a concern when compared to the results of Kaplan-Neeman et al. (2017) ; their rAlthough a relatively small number of respondents reported “using PLDs for more than 4 h” (17.3%) (Q39) and “using PLDs 21 or more times per year” (23.4%) (Q40), these results should be observed with caution. While updating the 60–60 rule , Portnuff and Fligor (2006) estimated that typical listeners could use their PLDs safely at 70% of full volume for 4.6 h a day if using the supplied earphones without greatly increasing their risk of hearing loss . NeverthWith respect to background noise, 86.3% of the respondents reported increasing the volume steps of their PLDs (Q44), which was also supported by several previous studies in which the preferred listening levels of PLDs increased with higher background noise ,34. For For college students, the main reason for using PLDs was to listen to music , and they considered PLD convenience to be an advantage . Also, they used their devices when feeling bored , to help them relax , to help them concentrate , and to isolate themselves from others . Indeed, music is known to stimulate the brain and change a listener’s emotional state, causing either relaxation or excitation . PLDs arMost (58.3%) of the college students did not have tinnitus (Q10). The students did not experience tinnitus 75.4%, Q49) or any other ear problem  because of their PLD use. Nevertheless, the experience of saying “huh?” or “what?” and asking for repeats was reported by 68% of respondents (Q12), but not because of the PLDs . Our participants did not concede any possible association between PLD use and this hearing effect. Also, our PLD users did not use them at sufficiently high intensity to undergo instant signs of hearing loss right after using the PLD. These patterns were similar to those found by Danhauer et al. [ or any oAmong the college students, 31.7% considered the acceptable age for using PLDs to be “5 to 10 years old” either 30.7% reported “11 to 13 years old” (Q54). These results are less conservative than Danhauer’s 2009) study which reported “11 to 13 years old” (39.2%) and “14 to 15 years old” (30.7%) [ study whFortunately, the students recognized that listening to PLDs at a high-intensity level can potentially cause hearing loss 90.7%, Q56). In addition to the hearing loss, students agreed that using PLDs could be dangerous in other situations, such as driving and snowboarding , and recognized their concentration on PLDs . Thus, we support more consciousness-raising messages that suggest that college students do not use their PLDs in situations that require their focused attention 0.7%, Q56, only 33About half of the respondents (56%) asserted that PLD manufacturers should provide a function of volume limitation for their customers. Although 65.3% of the Korean college students were not familiar with recommendations and conservation methods offered by the manufacturers (Q25), they positively responded to using volume control software given from the manufacturer . Additionally, they agreed that the ‘60–60 rule’  was not a violation of the public’s privacy 59.4%, Q28). Although these results were similar to those of Danhauer et al. [.4%, Q28.Of the respondents, 60.3% thought that current media, such as news outlets and journals, did not exaggerate the possible risk of a hearing loss caused by PLD use (Q61); however, 77.4% wanted to learn about potential hearing loss caused by excessive use of PLDs (Q62). The respondents preferred to obtain that information via e-mail 23.9%), TV (22.5%), and sometimes experts . Most of the students also wanted to be advised by a hearing professional 42%) and a doctor (36.6%) on how to prevent noise-induced hearing loss (NIHL) (Q64). Marron et al. (2015) supported this result; 84% of their respondents stated they would shorten the duration of their PLD use or reduce their listening level if given information by audiologists or doctors [% and a d%, TV  showed a prominent difference between the two questionnaires, as shown here in For the number of days in a week that PLDs were used, approximately 50% of the Korean students reported always using them in a week Q37, A. This up < 0.001) for the first hypothesis (H-1), meaning the data were suited for PCA using the varimax rotation method. The eigen values were 27.796, 19.111, and 15.704 for the three factors that contributed to their relationship. Because the PCA’s results demonstrated the factors and eigen vectors for each item, linear regression analysis was applied after conducting the PCA. The results of the Kaiser–Meyer–Olkin (KMO) and Bartlett’s tests were acceptably high at 0.835 (p < 0.001). Regardless, the interpretation should be different when considering the relationship between the factors and hearing problems. In terms of use time (Q39), the significance values mean the tendency of respondents that use PLDs for 0.5 to 4 h per day was less experience of tinnitus and less need to ask someone to repeat. The frequency of use was also significant and correlated with more questions of hearing problems (Q40). However, because the responses of Q40 were dichotomous regarding low-or high-use frequency, it should be carefully interpreted; the respondents used PLDs more than 4 h a day 1~3 times (36.7%) or more than 21 times (23.4%) in a year. In addition, the use time and frequency factor provided a weaker explanation at 0.072~0.127 than did the volume of PLDs. This relatively weak explanation is presumed to be due to the dichotomous response of Q40. Despite the dichotomy, the frequency of long-term use and hearing problems were not related. In other words, the use time and frequency of using PLDs among Korean college students was considered too insignificant to cause them to experience hearing problems .Although the volume of PLDs was statistically strong, it was also interpreted similarly to use time and frequency. For Q42, more than half of the respondents said that they usually set a ‘medium’ level volume. These results, understandably, are associated with less experience of hearing problems. Also, those respondents whose family, friends, or others had not warned them to turn down the volume of their PLD (Q48) were associated with less experience of hearing problems. In other words, Korean college students do not use volumes high enough to experience signs of hearing loss. As shown in p < 0.001). Four factors were confirmed, and their eigenvalues were 19.251, 11.607, 10.097, and 9.068. The results of multiple regression analysis for H-2 are shown in p < 0.001) and the information restriction , respectively, and had a positive attitude toward hearing conservation. However, the respondents of Q15 also partially supported Q61  with a temperate attitude toward hearing conservation.For the second hypothesis (H-2), the KMO and Bartlett’s measure was 0.702 (In terms of the relationship between the amount of knowledge about hearing loss and attitudes toward hearing conservation, the more subjects there were with knowledge of hearing loss, the more positive became the attitude toward informational and technical restriction . Thus, tThe Korean college students were aware of their listening levels and partially knew the maximum amount of time that they could listen at their chosen levels without risking hearing loss. Based on these current results, educational programs should provide more information on the effective actions necessary to minimize risk for hearing loss, while also increasing the public’s knowledge and consequently changing both people’s attitudes and listening habits. It is also crucial to develop appropriate standards and safe recommendations for daily music exposure in future studies that can confirm the longitudinal effect. We believe that these studies can provide further insights into the information educational institutions need to help establish a preventive program that can target the inappropriate use of PLDs effectively.


We investigated the health status of some workers exposed to occupational noise in Xinjiang, and explored the influencing factors of their health level. We aimed to determine the key protection groups of occupational noise hazards, which might provide the basis for the development of targeted noise prevention measures.We used descriptive analysis to investigate a total of 11,800 participants who underwent occupational health examination in Xinjiang Occupational Disease Prevention Hospital.2 = 54.507, p < 0.05). The abnormal rate of high-frequency hearing threshold in Xinjiang minorities was lower than in Han nationality , while the results of the electrocardiogram were reversed . Differences in abnormal rates of blood pressure , hearing , and physical examination  are statistically significant in different industries. The abnormal rates of blood pressure  and hearing  gradually decrease with the expansion of the enterprise scale. Logistic regression analysis showed that gender, nationality, age, enterprise size, and industry were closely related to pure tone audiometry examination abnormal rate.The hearing abnormality rate of noise exposure participants was 8.03%, which was higher in males than females (χWorkers of male, elder, in mine and small/medium enterprises should be the key populations to prevent occupational noise hazard. It is necessary to standardize occupational health management in enterprises, which helps to improve workers’ self-protection awareness and quality of life. Production noise refers to the noise generated from machine rotation, gas emission, workpiece impact, and friction. With the increase in industry numbers and sizes, production noise has become a recognized public health problem in the world. More than 600 million workers worldwide have experienced levels of occupational noise above hazardous thresholds . ApproxiThis study included 11,800 workers who underwent occupational health examinations at Xinjiang Occupational Disease Prevention and Control Hospital from January 1 to December 31, 2019, and whose occupational hazards were noise. All participants came from 168 companies, and the industries were divided into five categories , three enterprises scale . All participants signed informed consent forms and the study was approved by the Medical Ethics Committee of The Third People’s Hospital of Xinjiang Uyghur Autonomous Region (No. XJSQ20200428–10).The occupational health examination program was conducted in accordance with the Chinese occupational health monitoring regulations . The physical examination included blood pressure examination, electrocardiogram examination, pure tone hearing threshold test. There were two kinds of final results of occupational health examinations, abnormality or normal.The examinee rested for at least 10 min in a quiet environment. The physical muscles of the subject were relaxed, the palms were extended upwards, the elbows were at the same level as the heart, the cuffs were flat against the skin, and the elasticity was moderate. The lower edge was 1 to 2 cm higher than the elbows. Three measurements were performed at an interval of 5 min, using an electronic sphygmomanometer . The average of the measurement results was used. According to the World Health Organization standard classification, subjects with diastolic pressure > 90 and systolic pressure > 140 were defined as hypertension patients.Before the examination, workers rested in a supine position within 5-10 min. The electrocardiograph with conventional 12-lead electrocardiograms  was used to measure the electrocardiogram and was operated by a professionally trained doctor. The examinees were under supine measurement. The results were interpreted according to the international standard of ECG. All results were abnormal except for sinus heart rate.The examinees were required to avoid noisy environments for up to 12 h before the test. All subjects who underwent pure-tone hearing tests used a pure tone audiometer  in rooms with a background noise level of less than 25 dB. Both ears were tested using ascending pure tones at frequencies of 0.5, 1, 2, 3, 4, and 6 kHz. The test was repeated at least 3 times to determine the lowest signal strength as the final threshold for each ear. The average thresholds of 3, 4, 6 kHz were used to determine high-frequency hearing status. The binaural high-frequency average hearing threshold ≤ of 40 dB was treated as normal.P-value was < 0.05.Continuous data were shown as mean ± standard deviation. Student’s t-tests and ANOVA tests were analyzed by using independent-sample, LSD-t-tests were used to analyze Pairwise comparison between multiple groups. Qualitative data were analyzed by the Pearson χ2 test. Data were analyzed with IBM SPSS (ver 20). Differences would be considered significant if the ).This study included 11,800 workers (from 168 companies) with a mean age of 35.0 (range 18 to 66) years. There were 10,626 males, accounting for 90.5%, and 1190 minority employees, accounting for 10.08% (Table 1p < 0.05), but the working-age were slightly longer than female participants (p < 0.05), but the difference was not obvious. The abnormal rates of the electrocardiogram in Han participants were lower than other ethnic minorities (p < 0.05), but the abnormal rates of high frequency hearing threshold were higher (p < 0.05)(Table 2).The abnormal rates of ECG, blood pressure, and PTA in participants was 36.42, 17.37% and, 8.02%, respectively. There were 80.23% of participants who had at least one abnormal physical examination result. The abnormal rates of high frequency hearing threshold in male participants were higher than females (p < 0.05), and age had a greater positive impact on it. Except for the abnormal rates of electrocardiogram (p < 0.05), the results of occupational health examination of participants of different industries and different enterprise sizes had statistical differences. There were significant differences between the working-age groups in all industries (p < 0.05); the comparison between the age distribution groups in all industries  had significant differences (p < 0.05)  Table .Table 3p < 0.05); the age distribution of participants in large enterprises and small and medium enterprises had significant differences (p < 0.05)Table .Table 4p = 0.000). Compared with minorities, the Han nationality had a higher risk of high-frequency hearing threshold abnormalities . Elder workers had a higher risk of abnormal hearing threshold . Workers worked in small-scale companies have a higher risk of high-frequency hearing threshold abnormalities than those in large and medium-scale companies. Workers worked in the mining industry have a higher risk of high-frequency hearing threshold abnormalities than those in the other industries . According to the industry classification data of 186 enterprises, the large proportion of males is caused by the preference of mining and manufacturing industries for men in job selection and job demand.In general, the medical examination results of occupational noise-exposed workers were relatively poor, and 80.23% of these participants had at least one abnormal medical examination result. The abnormal rates of both ECG (36.42%) and blood pressure (17.37%) were high in participants. This suggests that noise exposure may have a greater effect on the cardiovascular system, we should pay more attention to the cardiovascular disease of workers, find the early risk of disease, and improve the health of workers.p = 0.000). This is consistent with the results of many studies in recent years. The cumulative occupational noise exposure is slightly higher in males than in females, which may also affect the medical results in addition to the gender differences. Therefore, we should focus on the results of occupational health inspections on male workers and increase the levels of protection for male workers. In 2018, Lin Daojian studied the hearing impairment rate (48.1%) of 2473 noise workers in Zhuhai City [Earlier studies had found that females were more sensitive to hearing at higher frequencies than males, but the result was contrary in low-frequency areas. With age increasing, the auditory function of male decays faster. The overall hearing functions of females are better than males, and occupational hearing losses in males are always higher than in females . There ahai City , and Qiahai City . HoweverEthnic minorities (Caucasian race predominates), except the Han, make up 60% of the total population of Xinjiang. This is a regional characteristic, and their appearances and living habits are significantly different from those of the Han nationality compared with other provinces in China. This study has found the abnormal rate of the electrocardiogram in ethnic minorities is higher than Han nationality, but the result of hearing impairment is reversed. Luo Rui has analyzed the electrocardiograms of the ethnic minorities (the Caucasian ethnic group) and the Hans in a physical examination in Xinjiang. They found that the abnormal rate of ECG in the ethnic minorities was significantly higher than Hans, which was consistent with our results . This isThe influence of aging in individuals is irresistible, which reduces the basic metabolism, organ senescence, and dysfunction. In this study, the noise exposure workers in the mining industry are the eldest, followed by those in electricity, heat and gas production and supply industries, other industries, and transportation, and final manufacturing. This is consistent with the detection rates of abnormal blood pressure and high-frequency hearing threshold. These abnormalities are possibly caused by age. Studies have shown that the effects of age and working-age accelerate age-related hearing loss, while there is a moderate degree of correlation between the accumulation of occupational noise exposure and age and hypertension . LogistiThe mining and the production and supply of electric heating gas industries have a high incidence of noise exposure and diseases induced by noise. Our logistic regression analysis has shown the risk of abnormal hearing threshold in mining is highest, but the occupational noise exposure workers in other industries have high blood pressure and high frequency hearing threshold abnormalities. Although there is less occupational noise exposure in some industries, workers in these industries still suffer hearing loss and health effects because of no awareness of occupational noise exposure and inadequate protection. Kerns had found that 31% of medical and diagnostic laboratory workers were exposed to noise and have substantial hearing impairments, which was higher than in the mining and construction industries . TherefoHowever, this study has found that the abnormal rate of blood pressure and high-frequency hearing threshold of exposed workers gradually decreases with the expansion of the size of the enterprise. The Logistic regression analysis has shown that workers working in small-scale companies have a higher risk of high-frequency hearing threshold abnormalities than those in large and medium-scale companies. Compared with large enterprises, small enterprises provide less prevention and education to workers, so that workers lack safety awareness and safety interventions , 12. OurThis study shows that workers who are male, elderly, or working in mining industries, or working in small-scale enterprises are vulnerable to noise damage and are also a key group for occupational noise protection. Enterprises in the mining industry should early protect hearing loss and noise-sensitive workers. Furthermore, multilingual training should be carried out to reduce the workers of the ethnic minorities from noise exposure. These populations will then get a better understanding of occupational hazards and their protection. Small businesses should also establish occupational health surveillance systems to promote sustainable development. This study analyzes the health effects of noise exposure on workers, which provides basic data for occupational health management in the region.This study may have some limitations. OAE tests can identify minor damage for hearing loss due to noise. It is also more objective than PTA, so future studies will use PTA to overcome this shortcoming. The cross-sectional design may limit causality, which is also the limitation of our article. In the future, we can use biological monitoring and noise dosimetry to assess occupational exposure more accurately.This study shows that male, elderly, mining industries and small-scale enterprises are vulnerable to noise damage and are also key groups for occupational noise protection. Enterprises in the mining industry should early detect those persons with hearing loss and noise sensitivity. Multilingual protective training should be carried out to ensure that workers of the ethnic minorities can conveniently communicate and get hazard-protection knowledge. Occupational health surveillance systems should be established in small businesses soon for their sustainable development. Our results of noise exposure on health effects in different industries and populations will provide the basis for future occupational prevention and management.


External housing-related control beliefs (HCB) and general self-efficacy (GSE) influence different health outcomes in the general ageing population, but there is no information of their role in people ageing with Parkinson’s disease (PD). This study aimed to longitudinally assess the role of external HCB and GSE on the association between housing accessibility and activities of daily living (ADL) among people ageing with PD.Baseline and 3-year follow-up data on 130 community-living participants from the Swedish project ‘Home and Health in People Ageing with PD’ were collected. Assessments addressed housing accessibility, external HCB, GSE, generic ADL and ADL specific to PD. The moderating effects of external HCB and GSE were assessed by including an interaction term in multivariable logistic regression.p = 0.03), and housing accessibility and external HCB on PD specific ADL (p = 0.03). After stratifying the analyses by GSE, housing accessibility problems led to more dependence and difficulty in ADL in participants with low GSE . After stratifying by external HCB, housing accessibility increased dependence and difficulty in PD specific ADL in participants with low external HCB .There were statistically significant interactions between housing accessibility and GSE on ADL (The results suggest that housing accessibility predicts ADL in people with PD with GSE and external HCB playing a moderating role for generic ADL and ADL specific to PD, respectively. Further longitudinal studies should validate these findings and explore their potential application in PD-related care and rehabilitation. Parkinson’s disease (PD) is the second most common neurodegenerative disease . Among pHousing accessibility is an indicator of person-environment fit , 8 and cA previous study showed that people with PD with more functional limitations and difficulties in ADL tended to rely more on external control  in order to manage their housing situation . GeneralGiven the existing evidence about housing accessibility, its effects on ADL dependence, with potentially moderating effects of control assigned over one’s housing and GSE, exploring these associations further in the PD population could provide useful insights for improving and facilitating treatment, care, rehabilitation, housing adaptations and housing provision. The aim of this study was to longitudinally assess the role of external HCB and GSE on the association between housing accessibility and ADL among people ageing with PD.N = 255), which included baseline assessment and a 3-year follow-up . The participants (ICD-10 diagnosis G20.9 for at least one year) were recruited from departments specialized in PD from three hospitals in the Skåne region, Sweden [n = 10) or with missing data on ADL dependence and difficulty (n = 23) at T2 resulting in N = 131. In addition, three persons had missing scores on external HCB, resulting in N = 128 for the analysis testing the role of external HCB. One person had missing scores on GSE, resulting in a sample size of N = 130 to test the role of GSE.We used data from the longitudinal ‘Home and Health in people ageing with PD’ (HHPD) cohort  . The resHousing accessibility at T1 was assessed with the Housing Enabler (HE) , an inteExternal HCB  at T1 were assessed by the self-reported Housing-related Control Beliefs Questionnaire’s (HCQ) scales of external control-powerful others (8 items) and external control-chance (8 items) . Each stGSE was assessed by the self-administered 10-item General self-efficacy Scale  at T1. EBased on previous literature , 34–42, Socio-demographic characteristics were either collected from the medical records or self-reported, and included age (in years), sex , marital status , education , country where they lived most of their lives (Sweden/other), satisfaction with one’s financial situation , type of housing tenure (owning/renting) measured at T1, and relocation and housing adaptations (occurred/not occurred) between T1 and T2. Clinical characteristics included self-reported depressive symptoms assessed with the Geriatric Depression Scale   and PD ds). The correlation coefficients were defined as very weak (0.0–0.2), weak (0.2–0.4), moderate (0.4–0.6), strong (0.6–0.8) and very strong (0.8–1). Differences across RAPS categories were tested by chi-square test, one-way analysis of variance (ANOVA) and median test for k samples.The strength of correlations was assessed by Pearson’s and Spearman’s correlation coefficients  and their 95% confidence intervals (CI). When the The analysis was conducted in IBM SPSS Statistics 24.0 .N = 130 sample  and ADL specific to PD  at T2 , respectively . As compared to models with RAPS and functional limitations only, when including the interaction terms between RAPS and GSE and RAPS and external HCB, the explained variance increased from 35 to 41% and from 32 to 37%, respectively , while there was no effect in the high GSE group . When stratifying the analyses by external HCB, RAPS increased the odds of difficulty in ADL specific to PD in participants with low external HCB , while there was no association in the high scorers .There were statistically significant interactions between RAPS and GSE on generic ADL , and between RAPS and external HCB on ADL specific to PD . Moreover, the moderating effects of external HCB or GSE were not consistent across the outcomes. That is, the interaction between RAPS and external HCB reached the predefined statistical significance on ADL specific to PD, while the interaction between RAPS and GSE only appeared to be statistically significant for generic ADL. A potential explanation for these differences might be the operationalization of each of the outcomes. In ADL Staircase the level of dependence and difficulty for each of the nine ADL items is scored separately, and based on both interview and observation during the home visit [s = 0.67). To summarize, the discrepancies probably reflect that these ADL assessments tap different ADL items and ways of assessment, and the participants might respond to different periods when being interviewed or having an explicit time frame to refer to.Two outcome measures for ADL were used in the current study, namely generic ADL measured by the ADL Staircase, and ADL specific to PD measured with PADLS. While the point estimates of RAPS on both outcomes when adjusted for functional limitations and the potential moderators were similar, only the association between RAPS and ADL specific to PD, and not the generic ADL, reached the predefined statistical significance  between external HCB and GSE was found in the present study, which indicates this difference. Furthermore, external HCB addresses proactivity specific to the home environment [The resulting moderation effects on housing and ADL dynamics might reflect that GSE and external HCB are different constructs that are not interchangeable. Self-efficacy is associated with locus of control , whereasironment , while Gironment . One couironment , this coThe results point to that GSE may be an important indicator of whether the housing environment affects dependence and difficulty in ADL. More specifically, the results suggest that we should be more proactive towards housing accessibility problems in people with PD who have low general self-efficacy as well as acknowledge self-efficacy in clinical PD-care and rehabilitation. Another study based on baseline HHPD data also showed that GSE was associated with perceived life satisfaction in people with PD , which up-value = 0.10) [In the Swedish younger old, no moderating effect of external HCB was found in relation to the ADL Staircase . In very = 0.10) . In the  = 0.10) , resultiThis is the first longitudinal study investigating the links between housing accessibility and health-related outcomes in people living and ageing with PD. Additionally, the role of GSE in the housing context and its effects on generic ADL as well as ADL specific to PD has never been tested before. In addition, while there were some missing data, our study sample was representative of the original follow-up HHPD cohort .Until recently, the measure commonly used to capture housing accessibility problems with HE had a major analytical limitation. As the variance of HE is mostly attributed to the functional limitations or  component, it hampered the possibility to estimate the effect of the environmental component on health outcomes . RecentlOne of the main limitations of this study is the small sample size. That is, we were not able to run analyses stratified by exposure and the moderators, which would have facilitated the interpretation of the results and more precise comparison to previous studies in the very old in the general population . We wereDue to the nature of the continuous RAPS score and that it could not be generated for those without functional limitations, we excluded 10 participants who had no functional limitations according to the HE, which limits the generalizability of the results. On the other hand, as the majority of people with PD do have functional limitations, overall the results are valid for the target population. Moreover, upon the presence of significant interactions, we stratified the sample for each of the moderators and were thus able to test the associations between RAPS and the outcomes in each stratum of interest.Another limitation is that due to low internal consistency of the internal HCB , the latThe results suggest that housing accessibility predicts ADL in people with PD with GSE and external HCB playing a moderating role for generic ADL and ADL specific to PD, respectively. Further longitudinal studies should validate these findings and continue to explore these intriguing mechanisms and their potential application in PD-related care and rehabilitation.


Delphinapterus leucas) in managed care are presented. Cochlear analysis of a 21-year-old beluga whale showed bilateral high-frequency hearing loss. Specifically, scanning electron microscopy of the left ear revealed sensory cell death in the first 4.9 mm of the base of the cochlea with scar formation. Immunofluorescence microscopy of the right ear confirmed the absence of hair cells and type I afferent innervation in the first 6.6 mm of the base of the cochlea, most likely due to an ischemia. Auditory evoked potentials (AEPs) measured 1.5 years prior this beluga's death showed a generalized hearing loss, being more pronounced in the high frequencies. This individual might have had a mixed hearing loss that would explain the generalized hearing impairment. Conversely, based on AEP evaluation, her mother had normal hearing and subsequent cochlear analysis did not feature any apparent sensorineural pathology. This is believed to be the first study to compare two cochlear analysis techniques and hearing sensitivity measurements from AEPs in cetaceans. The ability to combine morphological and auditory data is crucial to validate predictions of cochlear frequency maps based on morphological features. In addition, our study shows that these three complementary analysis techniques lead to comparable results, thus improving our understanding of how hearing impairment can be detected in stranding cases.Correlations between inner ear morphology and auditory sensitivity in the same individual are extremely difficult to obtain for stranded cetaceans. Animals in captivity and rehabilitation offer the opportunity to combine several techniques to study the auditory system and cases of hearing impairment in a controlled environment. Morphologic and auditory findings from two beluga whales ( Correlations between inner ear morphology and auditory sensitivity in the same individual are extremely difficult to obtain for cetaceans. Live strandings, animals in rehabilitation, and captive specimens are likely the only candidates that can provide such valuable information. Here, we present and compare the results of the inner ear analysis of 21-year-old (Qila) and 40-year-old  female beluga whales from the Vancouver Aquarium for which auditory evoked potential (AEP) thresholds were fortuitously measured 1.5 years prior to death.Previous studies on hearing loss in humans and terrestrial mammals have demonstrated structural alterations of the organ of Corti (or hearing organ) and associated innervation. These lesions have been attributed to mechanical damage and metabolic fatigue of the sensory cells and associated with high-intensity and/or long-duration sound exposure , exposurThere is a lack of ultrastructural analysis or characterization of the organ of Corti in most cetacean species. However, the normal morphology of the cochlea and changes in the morphology of the sensory cells along the cochlear spiral has been recently documented in beluga whales . CorrelaAEP measurements were conducted on the belugas Qila and Aurora in March 2014. The AEPs were elicited using an acoustic projector embedded in a suction cup (termed a “jawphone”) placed on the lower jaw near the commissure of the mouth . Although there is some degree of acoustic crosstalk between the two ears with this arrangement, it is likely that the AEPs are dominated by activity from by the ear closest to the jawphone, especially at threshold –13. Ther2/Hz from 10–60 kHz, and progressively decreased to ~15 dB re 1 μPa2/Hz at 180 kHz  were elicited using a 25-μs pulse  sent to the jawphone. The resulting “click” featured energy in the frequency region where belugas are sensitive, with a peak frequency near 100 kHz . StimulAll animal procedures and animal research were approved by the Vancouver Aquarium Institutional Animal Care and Welfare Committee.post-mortem. Her mother (40-year-old) Aurora succumbed on November 25th 2016, and her ears were fixed ~16 h post-mortem. According to a previous optimized protocol  tetrasodium salt hydrate, pH 7.4, at room temperature [changing the solution once every 7–10 days ] during After decalcification, the tympanic bone of Qila and the round window niche and surrounding tissue of Aurora were processed by conventional histology techniques with an automated processor (TissueTek). Tissues were embedded in paraffin, sectioned at 5 μm, and stained with Hematoxylin and Eosin, periodic acid Schiff's (PAS) and Twort's Gram stain.stria vascularis of the cochlea were exposed. Subsequently, the cochleas were dissected, dehydrated with increasing concentrations of ethanol, critical point dried with CO2, and then coated with gold-palladium. The samples were observed with an SEM at the University of British Columbia (UBC) Bioimaging Facility, Canada (Hitachi S-4700). Brightness and contrast of the figures were enhanced in Photoshop®.The decalcification of the left periotic bones ceased when the vestibular scala and the stria vascularis. The spiral ganglion cells were retained in most of the preparations, but the modiolus was removed.The right cochleas were dissected for immunofluorescence imaging using the whole-mount technique, following our recently optimized protocol . PreservThe flat cochlear sections were initially blocked with 5% normal donkey serum for 1 h at room temperature, incubated with the primary antibodies overnight at 4°C, then with secondary antibodies for 2 h in the dark, and for 30 min with DAPI , to counter-stain the nucleus. The following primary antibodies were used: (1) goat anti-prestin polyclonal IgG antibody , which labels the outer hair cells; (2) rabbit anti-myosin VI polyclonal antibody  that labels inner and outer hair cells, and (3) mouse anti-neurofilament 200 (phosphorylated and non-phosphorylated) monoclonal antibody IgG1 isotope , which labels type I afferent innervation that comprises 95% of the afferent innervation of the cochlea in some species of odontocetes  Specificity control ; (2) Control for non-specific binding of the secondary antibodies ; (3) Control for autofluorescence (no primary and no secondary antibodies were used).All fragments, including the controls, were treated with 0.2% Sudan Black B for 10 min after the secondary antibody to reduce the fluorescence of the tissue. The flat preparations were individually mounted on a glass slide with 0.1% N-propyl gallate in 90% glycerol and evaluated using fluorescence optic microscope and an Olympus FV1000 confocal microscope at the UBC Bioimaging Facility  and a Zeiss LSM880 confocal microscope at the Montpellier Resources Imagery . Micrographs of the three controls were obtained using the same magnification and same intensity of the four lasers as their respective treatments. Brightness and contrast of the figures were enhanced, using identical protocols for treatments and the respective controls.Click-evoked ABRs were recorded prior to measuring frequency-specific hearing thresholds. These were used as a rapid, gross measure of auditory function, and to ensure that all equipment was functioning properly. The resulting ABRs are shown for the belugas Aurora  were measured for both belugas. The thresholds for Aurora, Qila, and 26 wild belugas previously tested using similar AEP methods  are showNocardia paucivorans within the lung with reactive change in regional lymph nodes. Based on the extent and severity of inflammation and necrosis, this infection would have contributed at least moderately to impaired respiratory function. The proximate cause of death could be attributed to hypovolemic shock in the case of Aurora, secondary to liver and caudolateral and retroperitoneal hemorrhage, peritoneal rent and hemoperitoneum. The presumptive liver atrophy and hemorrhage, desquamated epithelia within the esophagus and nonglandular compartment of the stomach are consistent with inappetence or anorexia and may be related to the preexisting pathologic processes.Full necropsies of both belugas were conducted at the Animal Health Center, Abbotsford, BC, ~100 km east of the Vancouver Aquarium. Post-mortem examination of Qila revealed an infection of Aspergillus sp. . At present, there is little information regarding the pathology and neurophysiology of the cochlea in belugas, and the repercussions of the chronic inflammatory process found in the round window niche on hearing are unknown. Based on analysis of the ultrastructure of the hair cells (SEM and immunohistochemistry) and associated afferent innervation (immunohistochemistry), there was no evidence of hearing loss in either ear. Our anatomical results are thus consistent with the AEPs measured for this individual.Conversely, the results of the inner ear analysis and AEP measurements in Aurora were different. Although there were some artifacts attributed to It is unusual that two cetaceans in captivity die in a short time span (9 days apart). Although tragic, these mortalities afforded a unique opportunity to compare three methodologies and results obtained from two related individuals that shared the same environment for over 20 years with different hearing capabilities. Although the results of the post-mortem examination were different in both cases, both deaths were acute, and there is no clinical history, histopathologic or ultrastructural evidence that suggests that the cause of death was related with the hearing disorder found in Qila. The lack of detectable of type I afferent neurons and the presence of flat epithelium in the base of the cochlea can be an indication of an old lesion, and consistent with the results obtained with AEPs. In addition, we would have also found damage in the inner ear of Aurora if the lesions detected in Qila would have been related to the death of both individuals since Qila was a severe case. We do not expect that significant changes in the hearing capabilities of both individuals occurred between the measurement of their AEPs and their death and cochlear analysis 1.5 years later. There are detailed medical records for both animals in this time period. No ototoxic drugs were administrated, or clinical detection of infections that may have contributed to hearing loss in either of these individuals. Age-related hearing loss during this time period could be a factor to consider, but we would have likely detected it in Aurora as well, given that she was 19 years older than Qila.Although we compared the three techniques on two individuals and statistical analysis could not be conducted due to the small dataset, the fact that comparable results were obtained with all three techniques used shows that physiological and morphological test results can be correlated. This is particularly important because it is rare to have information on the cochlear anatomy and AEPs of the same individual: access to live animals is necessary for the measurement of AEPs, and rapid preservation of the hearing organs following death is required for cochlear anatomical analyses. The comparison shown in our study will be also useful in those circumstances when only one of the two methods  can be performed.in vivo, or where such data are not yet available. Further, studies on noise-induced hearing loss in terrestrial and marine mammals exposed to high noise levels show that the greatest losses of sensitivity regularly occurs at a frequency about half an octave, up to one octave, above the exposing tone (This study is the first to compare the findings of two cochlear analysis techniques and direct hearing sensitivity measurements from AEPs in a cetacean species. The ability to combine morphological and auditory data is crucial to validate cochlear findings in stranded cetaceans, as well as to validate predictions of cochlear frequency maps based on morphological features. Animals with hearing loss are of particular interest since they can further refine predictive models, and cases of high-frequency hearing loss will be crucial to localize the frequencies encoded in the first millimeters of the base of the cochlea. While AEPs on live strandings are a valuable tool to assess the hearing capabilities of species that cannot be kept in captivity , cochleaing tone , 45–47. The original contributions presented in the study are included in the article, further inquiries can be directed to the corresponding author/s.The animal study was reviewed and approved by the Vancouver Aquarium Institutional Animal Care and Welfare Committee. The ears from belugas were transported with the appropriate CITES permits.MM performed the inner ear extraction, dissection, their preparation for confocal and electron microscopy, and image interpretation. SR conducted the necropsies and histopathological evaluation of the tissues. JM measured the auditory evoked potentials in both belugas. MH, LB-L, and CN were in charge of the care of the belugas and associated research programs. FV helped with the evaluation of the results. MM, SR, JM, MH, LB-L, CN, FV, and RS helped with writing and editing the manuscript. RS and SR supervised the work and its publication. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.