Beauveria bassiana is an entomopathogenic fungus widely used as a biopesticide for insect control; it has also been shown to exist as an endophyte, promoting plant growth in many instances. This study highlights an alternative potential of the fungus; in the production of an industrially important biocatalyst, xylanase. In this regard, Beauveria bassiana SAN01 xylanase was purified to homogeneity and subsequently characterized. The purified xylanase was found to have a specific activity of 324.2 U·mg−1 and an estimated molecular mass of ~37 kDa. In addition, it demonstrated optimal activity at pH 6.0 and 45 °C while obeying Michaelis–Menton kinetics towards beechwood xylan with apparent mK, Vmax and catk of 1.98 mg·mL−1, 6.65 μM·min−1 and 0.62 s−1 respectively. The enzyme activity was strongly inhibited by Ag2+ and Fe3+ while it was significantly enhanced by Co2+ and Mg2+. Furthermore, the xylanase was shown to effectively deink wastepaper at an optimal rate of 106.72% through its enzymatic disassociation of the fiber-ink bonds as demonstrated by scanning electron microscopy and infrared spectroscopy. This is the first study to demonstrate the biotechnological application of a homogeneously purified glycosyl hydrolase from B. bassiana. B. bassiana, an endophytic fungal entomopathogen, appears to be a notable candidate in this regard, as the fungus has been shown to produce different enzymes in significant quantities and with distinct biochemical properties /v to [S] [catk (enzyme turnover number) and the catalytic efficiency were calculated accordingly [To evaluate the substrate specificity of v to [S] . Furtherordingly .B. bassiana SAN01 xylanase, was evaluated by SDS–PAGE. The analysis was carried out on a Mini PROTEAN gel electrophoresis unit  using 12% cross-linked polyacrylamide gels and 5% stacking gel [The molecular mass of the purified king gel . A wide v/v) Triton-X to renature the enzyme and washed in 50 mM sodium acetate buffer (pH 6.0) before final incubation in the same buffer [The sample was prepared in the standard SDS-PAGE treatment buffer without boiling and without a reducing agent. Afterwards, a zymogram was obtained using a 10% polyacrylamide gel containing 0.2% beechwood xylan . After electrophoresis, the gel was immersed for 30 min in 2.5% ; the resultant pulp slurry was drained using cheesecloth and oven-dried at 45 °C for 4 h. Subsequently, 400 mg dried pulp was incubated in 5 mL sodium acetate buffer  and subjected to different experimental conditions as summarized in The deinking of the printed paper was evaluated by recording the absorbance at 596 nm for the release of color (diazo reactive black 5) . All expPulp samples were gradually dehydrated with different gradients of acetone, followed by absolute alcohol, according to Chutani and Sharma . Subsequ−1, was used for the samples with an average of 32 scans [The surface functional groups of the enzyme-treated pulp and non-treated control was studied by Fourier transformed infrared (FTIR) spectrometry using the attenuated total reflectance (ATR) measuring cell. The infrared spectrometer  with a range of 650 to 4000 cmt-test were used for data analysis. The values p < 0.05 were considered significant.All experiments were performed in triplicates, and their average values with standard deviation were presented. One-way analysis of variance (ANOVA) and Student’s B. bassiana SAN01 xylanase produced under submerged fermentation was purified to homogeneity using a series of purification steps, including ammonium sulphate precipitation, ion-exchange chromatography, ultrafiltration and size exclusion chromatography. The xylanase was precipitated using ammonium sulphate (30–60% saturation) to yield an active pellet with a specific activity of 111.29 and 1.52 purification fold. The salt-precipitated enzyme preparation was then dialyzed and purified further by ion-exchange and size exclusion chromatography using Q Sepharose Fast Flow and Superdex 200 10/300 GL columns, respectively. The specific activity of the xylanase increased with each purification step to the maximum value of 369.39 U·mg−1 of protein after size exclusion chromatography. In addition, a 2.8% yield and a purification fold of 4.96 were achieved after the final purification step. The overview of B. bassiana SAN01 xylanase purification is summarized in B. bassiana SAN01 yielded a single band (Aspergillus oryzae [A. niger [B. bassiana xylanase curated on the UniProt database (UniProt ID: A0A0A2WJL0). The clear zone on the zymogram further confirms the xylanase band on SDS-PAGE and the desired molecular weight of the protein, which corroborates the xylanase activity.SDS-PAGE analysis of the purified xylanase from gle band a, which s oryzae , while lA. niger . FurtherB. bassiana SAN01 xylanase was observed to be pH 6.0, while it also exhibited significant activities between pH 5 and 8, showing 70 to 100% activity within that pH range . Other microbial xylanases that are active in the mesophilic range have been described recently. Examples include xylanases from Penicillium roqueforti [Pediococcus acidilactici [B. bassiana SAN01 was more stable than other fungal xylanases reported from Penicillium sclerotiorum [P. chrysogenum [The optimum temperature of the xylanase was observed to be 45 °C; however, it exhibited remarkable activity between 35 and 60 °C a. Beyondqueforti  and Pediilactici  with optrotiorum  and P. cysogenum , where aB. bassiana SAN01 xylanase. The enzyme activity was stimulated by Ba2+, Co2+ and Mg2+ and inhibited by Ag2+, Fe3+, Hg2+, Na+ and Cu2+, while Fe2+ and Zn2+ did not alter it significantly  to 107.92, 114.97 and 144.49% of its original value. Generally, it can be said that the xylanase was not affected much by the metal ions, as it retained >70% of its enzymatic activity in the presence of most of the ions investigated, at both 1 mM and 10 mM concentrations. The positive effects of Co2+ and Mg2+ on the activity of xylanase from Aspergillus ochraceus [Halomonas meridiana [2+ and Na2+ on xylanases from Paenibacillus sp. [Thermomyces lanuginosus [Subsequently, the activating and inhibitory effects of different compounds, including metal compounds, modulators, and organic solvents, were evaluated on ficantly . It is nchraceus  and Haloeridiana , respectuginosus , respectuginosus . BesidesB. bassiana SAN01 xylanase are shown in Additives such as EDTA, Triton X, SDS, among others, have been shown to have varying effects on different hydrolytic enzymes with accompanying effects during enzyme production or industrial application. The effects of some important chemical additives/reagents on the activity of B. bassiana SAN01 xylanase only at a higher concentration of 10 mM , hexane (120%) and ethanol (110%). In contrast, the enzyme was inhibited in the presence of acetone, butanol, benzene, methanol and toluene  and the catalytic efficiency (cakt/mK) of the enzyme under study were 0.62 s−1 and 0.3131 mL·s−1·mg−1, respectively. The cakt represents the amount of bound substrate molecules converted to the desired product per unit time, while cakt/mK measures the catalytic efficiency of enzymes for a specific product. The kinetic properties of us niger  and A. n. niveus  with Km B. bassiana SAN01 was evaluated against various polymeric substrates. It was observed that the xylanase had high specificity towards xylan-containing substrates  were also deduced from their respective p-values which were all less than 0.1. The model showed a high R2 value of 0.9955, indicating that the model can account for approximately 100% of the total variation and represent significant relationships among the chosen variables. The effect of the variable changes on the responses could also be observed on the contour and surface plots  as shown in ce plots a–c, show−1. The observed value of deinking, 106.72%, was close to that estimated by the RSM model, 113.19%. This demonstrates that the RSM with a central composite design analysis is efficient in optimizing xylanase-assisted deinking of printed paper.A validation experiment was carried out to establish the validity of the statistical experimental strategies. The experimental conditions were 40.17 °C incubation temperature, 17.7 h incubation time and an enzyme load of 983.6 U·mLB. bassiana SAN01 significantly modified the structure of pulp fibers. Compared to the control sample, more rugged surfaces, cavities, cracks and disorganized external fibers were observed in the xylanase treated pulp highlighting the alteration of the pulp fibrils at a molecular level resulting from the enzymatic attack. The observed extensive damage and greater porosity signify that B. bassiana SAN01 xylanase can degrade the xylan matrix that holds the pulp cellulose microfibrils, leading to surface ink detachment. Similar morphological changes at the ultrastructure level have been observed in enzyme-treated pulps [The morphological modification of the xylanase-treated paper pulp and untreated control were observed under the scanning electron microscope. The images  confirmeed pulps ,60.−1, which was present in all the paper samples, is ascribed to the hydroxyl groups of cellulose as well as hemicellulose  and lignin content . An earlier study has also shown higher peak intensity at the same wavenumbers in the control pulp in comparison to the treated pulp [−1 is believed to indicate the CH2OH group in ink and is observed to be less intense in the test samples. Furthermore, the peaks at 2851 and 2920 cm−1 represent the oil content of the ink and they were also of less intensity in the treated samples [The alteration in the structure of xylanase deinked paper samples was characterized using FTIR and compared with the untreated controls . The disted pulp . The pea samples ,62.B. bassiana SAN01 xylanase revealed it to be active and stable over a wide range of pH, from acidic to slightly alkaline. Furthermore, the enzyme was also shown to be moderately thermophilic with its optimum temperature at 45 °C. The purified B. bassiana SAN01 xylanase was stable in the presence of various metal compounds, organic solvents and other additives, making it a possible candidate as a biocatalyst in various bioprocesses. Finally, the xylanase was shown to efficiently deink wastepaper with an accompanying release of reducing sugars. Hence, in addition to the established safety of the fungus and its products, findings from this study further underscore the applicability of the fungus in many industrial processes. These findings are expected to stimulate the exploration of B. bassiana for industrial enzyme production and other bio-based products along with its well-established use as a biocontrol agent.The biochemical characteristics of


Well-being is influenced by the activities we undertake. Hearing loss may reduce well-being directly through increased listening-related fatigue due to cognitive and emotional strain in challenging situations. Hearing loss and hearing device use may also indirectly impact fatigue and well-being by altering the frequency and type of daily-life activities. This review examines the available literature to help understand the relationships.We provide (i) a summary of the extant literature regarding hearing loss, hearing device use and fatigue in adults, as well as regarding fatigue and daily-life activity  and (ii) a systematic search and narrative review of the relationships between hearing loss, hearing device use and activity.The systematic search resulted in 66 eligible texts.Data examining well-being in persons with hearing loss are limited. Our literature review suggests that well-being can be related directly and indirectly to hearing loss, hearing device use, activity level and listening-related fatigue.Variations and interactions between hearing loss, hearing device use, fatigue and activity levels can be expected to impact well-being in persons with hearing loss in direct and indirect ways. Future research linking hearing and daily-life fatigue should take account of activity levels. Well-being is often described as the state of being comfortable, healthy or happy  or long-term   with fatigue.Work activity can be viewed as either work status (i.e. in work versus unemployed) or the level of work activity such as the number of hours worked. With regard to the effect of the level of work activity on fatigue, evidence shows that high levels of work activity are linked to higher fatigue  has been identified in several studies as increasing feelings of energy and reducing fatigue  Is there a relationship between hearing loss and work, social or physical activity level? (Q2) Is there a relationship between hearing device use and work, social or physical activity level? Given the generally negative consequences of hearing loss and positive consequences of hearing device use, one would expect that hearing loss would be related to decreased work (referred to in the following as hypothesis H1_W), social (H1_S) and physical activity (H1_P), and that hearing device use would be related to increased work (H2_W), social (H2_S) and physical activity (H2_P). These six hypotheses were used as the basis for documenting the review.Systematic searches were conducted in five bibliographic databases: Embase, MedLine, Web of Science, Psychinfo and the Cochrane Library. The search variables used included control terms and free text terms. All English language peer reviewed research articles were included initially from inception until 1 February 2017. An updated search included all studies until 14 May 2020. The full search terms can be found in supplemental digital content 1.In order to determine which studies to include in the review, the Population, Intervention, Control, Outcomes and Study design strategy (PICOS) was utilised. The PICOS strategy is widely used in order to identify relevant studies for inclusion in reviews.The population was adults (>18 years old) with a hearing loss. The exposure variable of interest (“Intervention” in the PICOS framework) for (Q1) was hearing loss , and for (Q2) was hearing device use . All possible hearing devices were considered, although these were predominantly hearing aids and cochlear implants. The control was a population without the corresponding “intervention” of either hearing loss or hearing device, measured by within group comparison, between group comparison or within-subjects repeated measures design. The primary outcomes were work, social and physical activity. This was determined in terms of the quantity of each activity, rather than dysfunction, ability in or quality of the activity. Potential activity and qualitative aspects of activity such as enjoyment are all relevant and important aspects of the broader construct of activity. However, for this review we chose to focus on activity level because of its previously described link to fatigue and well-being. This review provides a starting point from which future research can build. Measures of activity level could be subjective or objective, measured over any timescale. Randomised controlled trials, non-randomised controlled trials, experimental studies with repeated measures design and observational studies were included. Qualitative studies were excluded from the review, as level/quantity of activity was of primary interest.After removing duplicates from the list of all articles identified from the searches of the databases, author JH screened the titles and abstracts for potential relevance. Once narrowed down, the reference lists of relevant studies were explored for additional relevant studies. Authors JH and GN then independently examined the full texts of the remaining potential studies. Studies were categorised as either “yes” where inclusion was certain, “maybe” when there was doubt, or “no” when the study did not meet the requirements for inclusion. The lists from each researcher were then compared, and any discrepancies were discussed and resolved.From the initial database searches, after removal of duplicates, 2977 studies were retrieved. Based on inspection of titles and abstracts this was then narrowed down to 127 studies. Through inspection and discussion between authors JH and GN, this was narrowed further to 58 studies. The reference lists of those selected studies were examined for potentially relevant literature. After an updated search in May 2020, eight further relevant studies were identified. Thus, a final total of 66 studies were identified to answer the two focussed research questions . Three sThe consolidated results and support for hypotheses are shown in Twenty-one studies were identified which addressed H1_W, that hearing loss is associated with decreased work activity. In general, the weight of evidence supported the hypothesis, with 17 studies reporting results that supported H1_W . The population under investigation was elderly in four studies  that hearing device use is related to increased work activity: five supported the hypothesis . Eleven studies addressed this issue and seven of these studies supported the hypothesis . Both studies investigated elderly populations. Stephens, Vetter, and Lewis  found noInvestigation of the role of activity in daily-life fatigue helped address in greater depth what previous literature can inform us about the relationship between hearing loss, hearing device use and daily-life fatigue, and by association how well-being can be affected. The literature regarding the relationships between both hearing loss and hearing device use and activity is varied: there are inconsistent methodologies across studies, and only one study out of 66 mentioned power analysis  via concomitant changes in work, social or physical activity. The enjoyment and control that a person has over a given situation is likely to be a key determinant of any resulting fatigue.Here we have demonstrated that not only is it possible that fatigue resulting from hearing loss could be directly related to well-being, but that changes in activity relating to hearing loss  could impact well-being both directly and through changes in fatigue.Given the important role of activity, knowledge of the activities undertaken by a person day-to-day is thus crucial to understanding the daily-life fatigue experienced. Therefore, future research into listening-related fatigue including measures of activity may serve to provide a better understanding of daily-life fatigue and its association to well-being.


HA; however, the typical coercivity values of commercial polycrystalline sintered magnets are only ~0.2 HA, which is known as Brown’s paradox. Recent advances in multi-scale microstructure characterizations using focused ion beam scanning electron microscope (FIB/SEM), aberration corrected scanning transmission electron microscopy (Cs-corrected STEM), and atom probe tomography (APT) revealed detailed microstructural features of commercial and experimental Nd-Fe-B magnets. These investigations suggest the magnetism of a thin layer formed along grain boundaries (intergranular phase) is a critical factor that influences the coercivity of polycrystalline magnets. To determine the magnetism of the thin intergranular phase, soft X-ray magnetic circular dichroism and electron holography play critical roles. Large-scale micromagnetic simulations using the models that are close to real microstructure incorporating the recent microstructure characterization results gave insights on how the coercivity and its thermal stability is influenced by the microstructures. Based on these new findings, coercivity of Nd-Fe-B magnets is being improved to its limit. This review replies to the most frequently asked questions about the coercivity of Nd-Fe-B permanent magnets based on our recent studies.Physically, the coercivity of permanent magnets should scale with the anisotropy field of ferromagnetic compounds,   For example, the typical value of coercivity, µ0Hc, for N50 type magnet with (BH)max~4 00 kJ/m3 is ~1.2 T, which is only ~15% of the anisotropy field of the Nd2Fe14B compound (µ0HA ~ 7.5 T) . Su. Su2Fe14exchange  29].Fi.Fi2Fe1413.9Fe79.5B6Cu0.1, which is slightly richer in Nd with respect to the stoichiometry of Nd2Fe14B, Nd11.7Fe82.4B5.8. In order to increase the coercivity of the Nd-Fe-B sintered magnet without using Dy, Nakajima et al. developed a Nd-rich and B-lean alloy with a trace Ga addition, i.e. Fe77.6RE14.8B5.1Cu0.1Ga0.5 as strip cast alloy for Nd-Fe-B sintered magnet with a substantially improved coercivity of 1.8 T for the grain size as large as ~5 µm [6Fe13Ga phases) are the main reason for the substantial enhancement of coercivity to 1.8 T upon post-sinter annealing [The addition of a small amount of Ga to Nd-Fe-B sintered magnets has been known to increase the coercivity by improving the wettability of the intergranular phase during post-sinter annealing . In earlas ~5 µm . Microstnnealing . Niitsu nnealing  also repnnealing .Figure HA, of the Nd-Fe-B sintered magnet with respect to the anisotropy field of the Nd2Fe14B phase is due to the intergranular exchange coupling through ferromagnetic intergranular phase.In short, low coercivity, 0.2 3.Hc = a – b lnD by Ramesh et al. [2Fe14B grains. However, as described above, the recent investigations showed that the Nd2Fe14B grains are exchange coupled in anisotropic Nd-Fe-B sintered magnets and the reduction of defect densities cannot explain the grain size dependence of coercivity. Moreover, coercivity decrease was reported for the grain size below 3 µm deviating from the linear grain size dependence of coercivity  Nd2Fe14B/Nd powders by He-jet milling and sintered the powders using the press-less sintering process in Ar atmosphere [D ~ 1 µm, and the coercivity of 2 T was demonstrated without alloying any HRE elements. A similar trend of grain size dependence of coercivity was also reported in the Ga-doped Nd-rich B-lean Nd-Fe-B sintered magnets in which a better magnetic isolation of Nd2Fe14B grains is realized via the formation of Nd6Fe13Ga intergranular phase as shown in 2Fe14B grains which becomes less effective as grain size decreases; as a result, the demagnetization field decreases in the smaller grain-sized magnets [cH(T) = αHA(T) – NeffMs(T) in which the first term is the influence of the defects and grain misalignment on the anisotropy field and the second term is related to the reduction of coercivity due to the demagnetization field [Neff, as shown in NeffMs, decreases as the grain size decreases, giving rise to a larger coercivity for smaller grain size. In the Nd-Fe-B sintered magnets, due to the surface machining or oxidations, the surface grains have reduced anisotropy field and hence almost no coercivity. Hence, the surface grains become multidomain at a remanent state and their magnetization reversal occurs at a much lower magnetic field than the nucleation field during the demagnetization process as often observed in the magneto optical Kerr effect microscopy  sintered magnets. Coercivity increases as the amount of Dy supply increases and it eventually reaches saturation. As shown in In order to understand the effect of coercivity increase in the course of the entire diffusion process including the Dy-diffusion and subsequent heat-treatment process, Kim et al. investigated the coercivity change in each step for Dy-free and Dy-containing samples and their microstructure change in details . Figure One of the long-standing questions on the HRE GBD process was the formation mechanism of a unique shell structure that is asymmetric with respect to grain boundaries. Seelam et al.  proposedIn short, the coercivity enhancement of HRE GBD processed magnets are not only due to the formation of the HRE-rich shell, but also due to the formation of the Nd-rich intergranular phase by the optimal post-diffusion annealing. The HRE-rich shell is formed by the CILFM, which explains the asymmetric feature of the HRE-rich shell.5.Hc of hot-deformed magnet as well. However, the conventional HRE GBD process applied on sintered magnets fail on the hot-deformed magnets as shown in Hc as the result of the coarsening of grains at the high processing temperature of ~900°C. In order to reduce the process temperature to suppress the grain coarsening  of the Nd70Cu30  or Nd90A [90Al10  alloys. Dy20Cu20 , Nd62Dy2Tb20Cu20 , the coesurfaces . Micromasurfaces  suggesteIn short, GB infiltration of low melting temperature Nd-HRE- eutectic alloys leads to a substantial increase of coercivity of hot-deformed magnets without inducing grain coarsening.6.2Fe14B so after initial DW displacements in the matrix, they are pinned at grain boundaries. This gives rise to the ‘two-step’ initial magnetization curves consisting of initial high susceptible region in the low magnetic field, where DWs in multidomain size grains displaces, and the susceptibility become low as the DW are pinned at grain boundaries. When the DWs are de-pinned, magnetization again increases to saturation as shown in 2Fe14B, which is valid to determine the single-domain size of a magnetized particle [The magnetization reversals in permanent magnets should at least consist of two steps: the nucleation of reversed domain and the propagation of DW throughout the matrix. Depending on which step controls the magnetization reversal, the coercivity mechanism is generally described as nucleation-control or DW pinning-control. In early studies of Nd-Fe-B sintered magnets with a large grain size of ~5–10 µm, the measured initial magnetization curve from a thermally demagnetized state always shows a large susceptibility, and the magnetization is easily saturated after applying a small external magnetic field. This ‘one-step’ initial magnetization curve was explained as evidence for the lack of effective DW pinning sites, indicating the nucleation-control reversal mechanism ,64. Howeparticle  but impr2Fe14B grain model. However, this simulation was carried out on a single crystal model. For simulating the magnetization behaviors of actual permanent magnets, the model must be exchange-coupled anisotropic polycrystals. Li et al. [Hc, it is concluded that the Hc mechanism is typical pinning type for the exchange-coupled sintered magnet and hot-deformed magnet. Micromagnetic simulation indicates that the mechanism would change to the nucleation type when grains are perfectly exchange decouples, while such exchange-decoupled magnets have not been demonstrated in the Nd-Fe-B system.Another method to characterize the magnetization reversal mechanism in the ferromagnetic materials is based on angular dependence of coercivity . Stoner–ulations ,76 show e et al.  showed todel see . Experim 1.6–2.0 ,75, indi 1.6–2.0 , which i 1.6–2.0  as the rd magnet , and a sIn short, the coercivity of the exchange-coupled Nd-Fe-B magnets can be explained by the DW pinning at the grain boundaries. The absence of the pinning feature in the initial magnetization curve is merely due to the multidomain state of large grains of the standard sintered magnets. When grain size becomes comparable to the domain size (~1 µm), the DW pinning by grain boundaries become visible in the initial magnetization curve. When grains are exchange decoupled by the formation of nonferromagnetic intergranular phase, the magnetization mechanism is expected to transfer to the nucleation mechanism, by which higher coercivity will be achieved.7.Hc at elevated temperature. One long-standing question about the temperature dependence of coercivity is its nonlinear change with concavity downwards with respect to the change of HA(T) as shown in Hc(T) and HA(T) cannot be explained with the well-known equation of coercivity, Hc(T) and HA(T) since microstructure parameter Hc(T) in the micromagnetic simulations  [Hc(T) has been reported in several works on eutectic diffusion processed hot-deformed magnet [High-temperature application is always a challenge for Nd-Fe-B magnet due to the severe reduction of i et al.  reproduculations ) that coof Hc(T) . In factd magnet  without Hc. The typical value of −1 at 160°C. An important feature about Neff can be reduced by decreasing the aspect ratio of the platelet-like grains [xMy  eutectic alloys [−1 at 500 K (see 0.8Ce0.2)-Fe-B hot-deformed magnet also led to a substantial improvement of the thermal stability of Hc, giving rise to the higher Hc at elevated temperature that is superior to that of Nd-Fe-B magnets.Conventionally, the thermal stability of coercivity of Nd-Fe-B magnet is quantitatively described by its temperature coefficient, n of βHc ,80, it iu et al.  which ore grains , which lins [βHc . On the  process , or the c alloys ,83–85. T00 K see . Tang etHA of Tb2Fe14B phase, Nd60Tb20Cu20 eutectic diffusion processed Nd-Fe-B hot-deformed magnet was found to show substantially improved −1 (500 K) as shown in 70Cu30 eutectic diffusion processed sample. Micromagnetic simulations by Li et al. [80Cu20 diffusion processed magnet was found inferior to that of Nd80Cu20 diffusion processed sample [2Fe14B HA.The formation of core–shell structure in HRE eutectic diffusion processed magnet was also found to be effective in improving the thermal stability of coercivity. Benefiting from the good thermal stability of i et al.  suggested sample , as a re2Fe14B shell in Nd2Fe14B grains. In particular, modifying GB to nonferromagnetic can suppress the concavity of Hc(T) curve and change the shape closer to HA(T).In short, the thermal stability of coercivity can be improved in the same approach of improving coercivity without using HRE, i.e. reducing the grain size, tuning the grain shape and modifying the GB magnetism, and it can be further improved by introducing 8.x1-LREx)-Fe-B magnets [2Fe14B compounds are inferior to those of Nd2Fe14B, limiting the performance of LRE-substituted permanent magnets; e.g. Ce2Fe14B compound has µ0HA = 2.6 T, µ0Ms = 1.17 T and Tc = 150°C with respect to µ0HA = 7.5 T, µ0Ms = 1.6 T and Tc = 320°C for Nd2Fe14B [xCex)2Fe14B by Susner et al. [Ms/f.u.) and anisotropy field can be well preserved up to x = 0.22. Hence, limited substitution of LRE elements such as Ce for Nd is expected to minimize the degradation of hard magnetic properties of (Nd1-xCex)-Fe-B-based magnets. An early work of Zhu et al. [2 and the lack of RE-rich intergranular phase were found to be a microstructure origin for the inferior extrinsic magnetic properties in the -Fe-B magnets [The ever-increasing demands on the Nd-Fe-B-based permanent magnets has raised concerns on the future supply chain of Nd which is the main rare-earth element used in these magnets. Although Nd is relatively abundant middle rare-earth elements, light rare earth (LRE) elements are always produced as byproducts and its effective usage is expected to reduce the entire cost of industrially useful rare-earth elements. Pathak et al. proposed the possibility of cost-effective permanent magnets by substituting part of Nd with LRE element, Ce, for Nd . Since t magnets . HoweverNd2Fe14B . Recent r et al.  have shou et al.  reportedu et al.  also sho magnets ,99,100.0.8Ce0.2)-Fe-B-based hot-deformed magnet exhibits the permanent magnet properties comparable to those for N42H class commercial sintered magnet as shown in 0.75Ce0.25)-Fe-B hot-deformed magnets as the result of the formation of -rich intergranular phase. The formation of Nd-rich 2:14:1 shell covering (Nd0.75Ce0.25)2Fe14B was another microstructure feature responsible for enhancement of coercivity. Although the Curie temperature of Ce2Fe14B is much lower than that of Nd2Fe14B, the 20%Ce-substituted anisotropic magnet showed the hard magnetic properties comparable to those of N42H-grade commercial sintered magnet with a similar RE concentration of 15 at.% as shown in oC, which is superior to that of N42H. The origin of the improved temperature coefficient of coercivity of the Ce-substituted hot-deformed magnets was attributed to the low magnetization of the -enriched intergranular phase and the formation of high-HA Nd-rich shell. These reports clearly show -Fe-B-based hot-deformed magnets with optimized microstructure can be considered as low-cost high-performance permanent magnets [Recently, TOYOTA motor corporation announced that a LRE-substituted hot-deformed magnet showed superior temperature coefficient of coercivity compared to the conventional sintered magnets . However magnets .Figure In short, serious degradation of coercivity and remanence by substituting Nd with Ce in Nd-Fe-B magnet can be avoided by the microstructure optimization as long as the Ce concentration ratio, Ce/RE, is controlled smaller than 30%. The origin of the improved temperature coefficient of coercivity is the formation of -rich intergranular phase and Nd-rich shell.9.Neff to approach the limit of intrinsic HA. Factor Neff. However, this approach failed in the magnet with submicron grain size which was produced by hydrogenation–disproportionation–desorption–recombination (HDDR) and press-less sintering process (PLP) since the thin intergranular phase is ferromagnetic [2Fe14B grains. The hot-deformed magnets which consist of submicron-sized grains show µ0Hc values in the range of 1.0–2.0 T that are comparable with that of sintered magnets with a grain size generally much larger than 1 µm. Although the engineering of the intergranular phase via eutectic diffusion process in the hot-deformed magnets results in a substantial enhancement of coercivity, further enhancement of coercivity is expected if the side GB phase can also become paramagnetic. Note that the current experimental knowledge has no answer on how to fully exchange decoupled Nd2Fe14B grains in the anisotropic ultra-fine grain-sized Nd-Fe-B magnets.The ultimate performance of coercivity and its thermal stability is expected in a magnet with maximized anisotropy factor magnetic . This reL is the total size, D is the block size and t is the thickness of the intergranular phase. For a GB thickness of t = 3 nm and a requirement of limited volume fraction of GB, e.g. On the other hand, the volume fraction of intergranular phase increases with reducing grain size, which will lead to a drop of remanence if all the grain boundaries are nonferromagnetic. As a simple demonstration, the volume fraction of intergranular phase in a stack of cubit blocks is given by HA/2) [HA shell enveloping the exchange-decoupled Nd2Fe14B grains can further improve Hc and HA of the Nd2Fe14B phase. Since its mechanism is to force a relocation of nucleation site from grain surface to the core/shell interface where the demagnetizing field is smaller [Hc and 2Fe14B.Based on the above discussion, the ultimate performance of extrinsic property is expected in a magnet with grain size around several hundred nanometers, equiaxed shape, uniformly separated by nonferromagnetic intergranular phase (i.e. exchange isolated). As a reference, micromagnetic simulation consisting of exchange-decoupled equiaxed grains with a size of 100 nm predicted a coercivity of 3.5 T (~HA/2) . The for smaller , Hc and HA/3) and the simulation predicted coercivity in an optimal microstructure (~HA/2). It is expected to fill the gap by further reduction of the grain size and magnetic isolation of Nd2Fe14B grains with thin nonferromagnetic intergranular phase, which has not been realized yet. Materials informatics and active learning [The recent advances on the multi-scale microstructure characterizations have broadened our understanding on the coercivity mechanism of Nd-Fe-B-based magnets leading to a substantial improvement on coercivity and its thermal stability in the last decade. However, still there is a gap between the experimentally achieved coercivity (≲learning , which h


Age-related hearing loss (ARHL) may limit communication, which is closely associated with cognitive decline of the elderly and negatively affects their quality of life. In ARHL patients who suffer chronic otitis media (COM), hearing impairment may worsen and negatively affect the cognition and quality of life. It is currently unknown whether restoration of the conductive hearing in the mixed hearing loss through middle ear surgeries can improve both the cognitive function and quality of life of the ARHL patients. Therefore, in the present study, the ARHL patients were followed up for 6 months after middle ear surgeries for COM, and both the cognitive functions and quality of life of the patients were assessed using Montreal Cognitive Assessment and Glasgow Benefit Inventory. It was found that both the cognitive functions and quality of life were improved 6 months after middle ear surgeries. In conclusion, hearing recovery after middle ear surgeries could improve cognitive functions and quality of life of ARHL patients with COM, and surgical intervention is, hence, recommended for COM. With global aging, the number of age-related diseases is increasing. According to the WHO, hearing loss is the second cause of disability throughout the world, over 42% of which is age-related hearing loss (ARHL) . ARHL, which is also called presbycusis and characterized by progressive bilateral, symmetrical, sensorineural hearing loss, may limit communication and has a close relationship with cognitive decline and even dementia , negativTo date, the treatment of hearing impairment in senile population is hearing aids and cochlear implantation. Cochlear implantation is indicated for patients with severe to profound sensorineural hearing loss who cannot benefit from hearing aids . MoreoveHowever, it is currently unknown whether correction of the conductive hearing in the mixed hearing loss through middle ear surgeries can improve both the cognitive function and quality of life of the ARHL patients.Therefore, the aim of the present study was to investigate whether middle ear surgeries could improve the cognitive functions and quality of life in elderly patients who suffered both ARHL and COM, and to further investigate the mechanisms related to the relationship between hearing loss and cognitive impairment.Patients aged over 60 years who were diagnosed with both ARHL and COM and underwent tympanoplasty under general anesthesia by experienced otologists in our department from January 2015 to December 2020 were included in this study. The purpose of the study was explained to the patients, and informed consents were obtained from all the participants. The protocol was approved by the Ethics Committee of Beijing Tsinghua Changgung Hospital.Exclusion criteria: (1) patients who were not benefited from middle ear surgeries ; (2) patients who had moderate, severe, or profound ARHL and are not benefited from middle ear surgeries; (3) patients who suffered active COM or were complicated by cholesteatoma; (4) patients who had history of middle ear surgeries or were combined with middle ear tumors; (5) patients who had received hearing aids before; (6) patients who had visual impairment that limited the cognitive test; and (7) patients who suffered from diseases that may interfere the cognition or quality of life during the 6-month follow-up after operation, such as cerebrovascular disease, craniocerebral trauma, schizophrenia, sudden hearing loss, severe tinnitus, etc.Patients included in our study were examined by the same audiologist. Pure tone audiometry (PTA), SDSmax tests, and temporal bone high-resolution CT (HRCT) were carried out before operation and 6 months after operation, respectively. The average hearing threshold was calculated based on all PTA frequencies at the surgical side. Hearing loss was categorized based on the classification proposed by the WHO : normal hearing, less than 20 dB HL; mild hearing loss, 20–35 dB HL; moderate hearing loss, 35–50 dB HL; moderately severe hearing loss, 50–65 dB; severe hearing loss, 65–80 dB HL; profound hearing loss, 80–95 dB HL; and complete or total hearing loss, 95 dB or greater.The continuity of the ossicular chain was checked by temporal bone HRCT before operation. During operation, we attempted to preserve the ossicular chain if the mobility was good (type I tympanoplasty). Ossicular chain reconstruction during tympanoplasty was performed when the incus was eroded  or the stapes was eroded . Perforation of the tympanic membrane was repaired using a fascia graft and/or tragus cartilage.Cognitive performance was assessed using Montreal Cognitive Assessment (MoCA), by a separate observer. The MoCA consists of seven subsections, including Visuospatial/Executive, Naming, Memory, and Delayed Recall, Attention, Language, Abstraction, and Orientation. According to the answers, the total score ranges from 0 to 30.Quality of life was assessed using Glasgow Benefit Inventory 9. Glasgow Benefit Inventory is a kind of questionnaire covering 18 questions, which addresses changes in quality of life after operation. The scores for each question range from 1 to 5: 1, the worst change; 5, the best change; and 3, no change. The numerical data from the questionnaire were then converted to a GBI index score ranging from −100 (the worst outcome) to +100 (the best outcome). GBI consists of three subscales: general subscale scores, social support scores, and physical health scores. The Glasgow Benefit Inventory is a systematic review of the use and value of an otorhinolaryngological generic patient-recorded outcome measure.The MoCA assessment was performed before middle ear surgeries and 6 months after operation, respectively, and the scores were compared. The GBI assessment was performed 6 months after operation.t-test, and p < 0.05 was considered statistically significant. Concerning multivariate analysis for improvement of the total MoCA scores and the seven subsection scores, p < 0.025 was considered statistically significant (one-tailed test). Pearson’s correlation analysis was performed to determine the correlation between hearing improvement and MoCA/GBI. SPSS 22.0 program  and GraphPad Prism 6.05 software  were used for statistical analysis.Quantitative data were expressed as mean ± standard deviation (SD). The parametric data were compared using the paired A total number of 29 patients, including 23 females and six males, were enrolled in the study. The age of the subjects ranged from 60 to 74 years, with a mean age of 65.6 ± 4.7 years. All patients were diagnosed with ARHL and COM, and underwent tympanoplasty. The demographic features and treatments of the subjects are shown in To intuitively evaluate the surgery outcomes, all patients underwent temporal bone HRCT before and after operation. Tympanoplasty in the present study could reconstruct the middle ear into a normal anatomical structure to the maximum extent , 2.The preoperative and postoperative hearing function is shown in The preoperative and postoperative SDSmax is shown in p < 0.0001). As shown in p < 0.0001). Furthermore, the Visuospatial/Executive, Memory and Delayed Recall, and Attention were also improved, with p < 0.05.The MoCA assessment was performed before operation and 6 months after operation, respectively. The preoperative and postoperative MoCA total scores and subsection scores were compared . ConcernThe multivariate analysis showed that improvement of the seven subsections at 6 months after operation was included as an independent variable, and improvement of MoCA scores was the dependent variable . Our rest-test, it was found that the subsections of Language and Visuospatial/Executive were associated with the total MoCA improvement.According to the results of paired The GBI assessment was performed 6 months after operation. The average benefit at 6 months after operation was found to be +22.8 ± 16, suggesting that the overall quality of life of the patients was significantly improved after operation. The three subscales of GBI were analyzed separately, with general benefit of +21.4 ± 21.1, social benefit of 40.8 ± 28.4, and physical benefit of 10.3 ± 13.7.To explore whether cognitive improvement or improvement of quality of life is correlated with hearing improvement, Pearson’s correlation analysis was performed. As shown in In the present study, it was found that cognitive functions were improved after tympanoplasty for ARHL and COM. ARHL is a highly prevalent disability in later life, affecting the cognitive capacity of the elderly and even leading to dementia, which has posed a serious threat to quality of life . FurtherAlthough tympanoplasty and hearing aids can both improve hearing, they are quite different from each other. In the current study, after a 6-month follow-up, it was found that the cognitive functions, especially the language capacity, were significantly improved in the ARHL patients with COM after tympanoplasty. The main difference between hearing aids and surgeries is that hearing improvement is lasting for the patients receiving surgeries, while it is discontinuous for hearing aid users . Until nFurthermore, we also assessed the quality of life of the patients at 6 months after operation by Glasgow Benefit Inventory, a well-established validated questionnaire used to measure the results of surgical interventions. GBI is widely used to assess the QoL of the patients after ENT surgeries with good reliability. Furthermore, GBI, Chinese version, has also been evaluated by Therefore, for ARHL patients with COM, active surgical intervention for COM is recommended because hearing improvement may result in cognitive improvement and improvement of quality of life. Because tympanoplasty is performed under general anesthesia, surgical complications seem to be the greatest concern. Although it was found that tympanoplasty could improve both cognitive functions and quality of life, some limitations must be considered in the present study. First, the sample size in the study was relatively small. However, as there are few similar studies, it adds important knowledge to the current field. Second, the current research focused on the relationship between hearing improvement after middle ear surgeries and cognitive functions/quality of life. The correlation between relief of other discomforts and cognitive functions, such as otorrhea and tinnitus, was not studied. In the future studies, we will conduct COM-specific questionnaires  on the pThe raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.The studies involving human participants were reviewed and approved by the Ethics Committee of Beijing Tsinghua Changgung Hospital. The patients/participants provided their written informed consent to participate in this study.HY conceptualized and designed the study and approved the final version of the manuscript. JG prepared the draft of the manuscript and made revisions. JC followed up of patients and handled the acquisition of the data. JX and SL performed the analysis and interpretation of the data. 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.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


Cisplatin is a popular antineoplastic agent used to treat cervical cancer in women from low and middle-income countries. Cisplatin treatment is associated with ototoxicity, often resulting in hearing loss. In light of this, it is crucial to conduct baseline audiological assessments prior to treatment initiation in order to evaluate the extent of cisplatin-associated-ototoxicity. Additionally, the identification of inherent risk factors and hearing patterns in specific patient cohorts is needed, especially in South Africa, a middle-income country characterized by the quadruple burden of disease (Human Immunodeficiency Virus (HIV), Tuberculosis (TB), Diabetes and Hypertension).This study aimed to describe a profile of risk factors and hearing in a cohort of females with cervical cancer before cisplatin treatment commenced. A descriptive study design that included 82 cervical cancer patients, who underwent audiological evaluation prescribed for ototoxicity monitoring was conducted.All participants (n = 82) presented with risk factors  for cisplatin ototoxicity and/or pre-existing sensorineural hearing loss. High-frequency tinnitus was the most common otological symptom experienced by 25 (31%) participants. Fifty-nine (72%) participants presented with normal hearing, twenty-two (27%) with a sensorineural hearing loss, and 36% were diagnosed with mild hearing loss. Abnormal Distortion Product Otoacoustic Emissions (DPOAE) findings were obtained bilaterally in two participants (2.4%), in the right ear only of another two (2.4%) participants and the left ear of three participants (3.7%). Most participants (94%) had excellent word recognition scores, demonstrating an excellent ability to recognize words within normal conversational levels under optimal listening conditions. Age was significantly associated with hearing loss at all thresholds. Among the co-morbidities, an HIV positive status significantly triggered hearing loss, especially at higher frequencies.This study demonstrated that South African females with cervical cancer present with various co-morbidities, which may predispose them to develop cisplatin-associated -ototoxic hearing loss. Identification of these co-morbidities and hearing loss is essential for the accurate monitoring of cisplatin toxicities. Appropriate management of these patients is pivotal to reduce the adverse effects that hearing impairment can have on an individual’s quality of life and to facilitate informed decision-making regarding the commencement of cisplatin chemotherapy.The online version contains supplementary material available at 10.1186/s12905-021-01313-5. Hearing loss has now been identified as the fourth highest cause of disability globally, with South Asian, Asia Pacific, and Sub-Saharan African regions being the most affected. This is evident by prevalence rates being almost four times higher in low-income compared to high-income regions . While tFemales with cervical cancer are identified as an “at-risk” cohort for ototoxicity in South Africa. It is the second most common cancer diagnosed in women in South Africa, with an age-standardized incidence rate of 26.96 per 100,000. Additionally, 1 in 35 women presents with a lifetime risk 0–74 years) of developing cervical cancer [ years ofCisplatin is a popular and effective antineoplastic drug used in the treatment of many cancer types, including cervical cancer; however, it is well-known for its ototoxic side effects . The latth nerve, or opportunistic infections associated with hearing loss [Further complicating the situation for women with cervical cancer is their diagnosis of HIV, which requires the concomitant use of antiretroviral therapy (ARTs). This is problematic since cervical cancer is regarded as an AIDS-defining illness, and HIV in itself, has been reported to cause hearing loss . Proposeing loss . Furthering loss . As a reing loss , 14, cuming loss , 16¸ exping loss , chemicaFurther complicating this disease profile is the increasing incidence of non-communicable diseases (NCDs) , includiGiven the potential for combined co-morbidities, and the resultant exposure to ototoxic medication, the need for baseline audiological monitoring is pivotal to provide a frame of reference for future audiometric testing in complex disease profiles. Determining changes in hearing ability over time will significantly contribute to a better understanding of the associated risk characteristics as well as identify how hearing loss manifests in complex disease profiles before cisplatin chemotherapy. Furthermore, obtaining baseline audiometric results may prevent misinterpretation of high-frequency hearing loss when monitoring cisplatin ototoxicity, since presbycusis (hearing loss due to age) may mimic the configuration of cisplatin ototoxicity, as both manifest in a high-frequency sensorineural hearing loss . AdditioFindings reported in this paper form part of a prospective cohort study among cervical cancer patients before cisplatin exposure.The study was conducted at a referral hospital offering tertiary services in KwaZulu-Natal (KZN), South Africa, as defined in the regulations relating to categories of hospitals . This siPatients attending the hospital’s oncology clinic who met all the inclusion criteria were identified, informed of the study and subsequently invited to participate by the clinicians, nurses as well as the primary investigator. Of the 86 patients who responded to the invitation, 82 adult females (≥ 18 years) with a diagnosis of cervical cancer were recruited before the commencement of the first cycle of cisplatin-based chemotherapy. Patients presenting with profound hearing loss at baseline assessment, or those who had previously received cisplatin chemotherapy or had a history of medical conditions such as tuberculosis, and malaria were excluded. Four of the 86 patients were excluded, as one had previously received chemotherapy, while the other three were treated with aminoglycoside antibiotics following a diagnosis of multi-drug resistant tuberculosis (MDR TB). All participants were tested for HIV, and those who were diagnosed as being HIV positive received antiretroviral therapy as part of the clinical management.Following written informed consent, participants’ medical records were reviewed. Additionally, a structured questionnaire  at the different frequencies was analyzed separately for the left and right ear. Risk factor information was gathered from patients’ self-reports and medical records and was stratified into two risk categories . The results of the audiological assessment were analyzed as per normative data indicated in Additional file The Tobit (censored) regression was used to estimate the linear relationship between hearing loss and risk factors, adjusted for age, as it accounted for non-responses  with daily biological checks conducted by the primary researcher.Data from 82 female patients with cervical cancer were analyzed, and the demographic and medical characteristics are summarized in Table A summary of the self-reported audiological symptoms is presented in Table Abnormal otoscopic findings  were evident in the right ear of one participant (1.0%), and the left ear of another participant (1.0%). Tympanometric findings revealed normal results, i.e., Type A tympanograms in 81 (98.8%) participants bilaterally. Acoustic reflex threshold testing revealed abnormalities in the right ear of 33 participants (40.0%) and the left ear of 38 participants (46.0%).Moreover, hearing loss was identified in the right ear of five participants (6.0%) in the left ear of six participants (7.0%) and bilaterally in 17 participants (21.0%). Of the participants with bilateral hearing loss, five (17.0%) had indicated reduced hearing sensitivity. Among those participants with bilateral hearing loss (n = 17), five (17.0%) reported experiencing tinnitus. Complaints of tinnitus were also reported by two (33.3%) of the six participants with hearing loss in the left ear only and two (28.7%) of the seven participants with hearing loss in the right ear only. Mixed hearing loss was identified in the right ear of one participant and the left ear of another, with the remaining participants presenting with sensorineural hearing loss. Mild hearing loss was most common (35.0%), followed closely by mild-moderate, and this pattern was evident bilaterally.A steady decline in the number of participants with hearing thresholds between -10 and 25 dB was seen as the frequency increased, as indicated in Fig. Additionally, the speech reception threshold (SRT) testing revealed good SRT-PTA correlation in more than 95% of the participants bilaterally; thus, confirming the validity of pure-tone test results. Word recognition score testing showed that most participants had an excellent ability to understand speech within normal conversational levels under optimal listening conditions.Moreover, 73 (89%) participants presented with one or more risk factors for hearing loss, as indicated in Table p < 0.0001) between HIV status and the use of ototoxic medication. Hence, we excluded the use of ototoxic medication to avoid the multi-collinearity problem. Age, being a confounding variable, was accounted for in the multiple regression model. Results of simple and multiple regression models are depicted in Tables Additionally, simple and multiple Tobit regressions were fitted to test the association between the hearing loss at various frequencies and covariates such as age, HIV status, NCDs , and use of ototoxic medication. All HIV positive patients took ototoxic medication, supporting a significant correlation  can potentiate auditory dysfunction that is greater than the sum of each insult given individually, implying a synergistic effect . In agreFurthermore, if a person presents with more than one of these medical conditions, i.e., diabetes, hypertension, and/or HIV as they age, there is likely to be an even greater antagonistic, additive effect on hearing that may progressively worsen during the course of cisplatin chemotherapy. This, therefore, reinforces the importance of the audiologist conducting a detailed case history at baseline so that they may be able to identify probable reasons for the otological symptoms experienced as well as the audiological profile of the patient.A review of the audiological profile at baseline revealed high-frequency tinnitus to be the most common self-reported otological symptom. While tinnitus is often associated with a hearing loss, the number of participants with self-reported hearing difficulties and even those with clinical hearing loss was lower than the complaints of tinnitus in our study. This finding should be of no surprise, taking into consideration that most participants presented with other medical conditions, namely diabetes, hypertension, and HIV, and its associated treatments of which has been reported to cause tinnitus as a side effect . These fComplaints of otalgia appeared to be much lower than expected (6%) when compared to previous literature focusing on HIV infected participants in South Africa, which indicated that 19% of the sample reported otalgia . It is, The small number of participants presenting with a history of ear infections and/or otoscopic and tympanometric abnormalities is a rare contradictory finding because more than 50% of the current study participants are HIV positive and previous reports otitis media to be most common in this population , 41. HowThe percentage of participants with hearing loss (27%) at baseline in this current study is in agreement with Nagy et al., who reported that 26% of the study sample presented with hearing abnormalities . The numFurthermore, if the extended high-frequency audiometry thresholds were considered in the general classification of hearing loss, more participants would likely be presenting with hearing loss. However, due to the lack of consensus around normative data for the extended frequency range, none of the classification systems for hearing loss consider this frequency range. Consequently, this data was merely used in this baseline study to reflect that the audiometric patterns were of a sloping configuration. The sloping configuration of the audiological patterns is congruent with other test findings and the demographic and medical profile of the participants. These findings are in agreement with previous reports, as with increasing age , hyperteThe highly limited occurrence of conductive hearing loss is in agreement with other South African studies , 45, 46.Due to the sensorineural nature of the hearing loss, one would expect most of these participants to present with reduced or absent DPOAEs. DPOAEs are generally absent in frequency regions with pure tone thresholds greater than 50 dB [Most participants presenting with normal hearing or mild degrees of hearing loss may also account for the excellent word recognition scores. This, therefore, corroborates with the small number of participants self-reporting hearing difficulties. Our findings are in agreement with that of Sooy , who alsFurthermore, due to the absence of a validated speech wordlist for isiZulu speakers, a decision was taken to utilize the Digits test for speech recognition threshold testing  and a spWhile the current study has been conducted in South Africa, other countries experience similar issues regarding disease complexity, as reflected by the World Health Organization report (2018). In 2014, the World Health Organization indicated that one in four men and one in five women  had hypertension globally, while the number of people with diabetes has nearly quadrupled since 1980 from 108 to 422 million in 2014 . Thus inThis study has demonstrated that this cohort of South African women with cervical cancer presented with various risk factors, such as HIV infection, diabetes, hypertension, ototoxic medication, and pre-existing hearing loss, all of which may predispose them to develop cisplatin hearing loss. Considering that South Africa is burdened with a high prevalence of both infectious and NCDs, it is essential that a patient’s hearing is assessed before commencing cisplatin chemotherapy. This will enable the identification of known risk factors in an attempt to manage the patient as well as accurately monitor the impact of cisplatin ototoxicity. Our findings revealed the presence of a clinical hearing loss in the absence of symptoms; mild high-frequency hearing loss may go unnoticed unless there is routine monitoring of patients before, during, and post-chemotherapy. Furthermore, permanent sensorineural hearing loss emphasizes the need for possible referrals to other healthcare professionals, including psychologists and occupational therapists as hearing loss may impact on all facets of life . AdditioAdditional file 1. Case History QuestionnaireAdditional file 2. Audiological Equipment, Motivation, and ProcedureAdditional file 3. Clinical Analysis of DataAdditional file 4. Limits of the audiometer


Among them, qCTB-1-1 overlaps with Osa-miR319b, a known cold tolerance micro RNA gene. The other three qCTBs have not been reported. In addition, we characterised the candidate gene OsRab11C1 for qCTB-1-2 that encodes a Rab protein belonging to the small GTP-binding protein family. Overexpression of OsRab11C1 significantly reduced CTB, while gene knockout elevated CTB as well as cold tolerance at the seedling stage, suggesting that OsRab11C1 negatively regulates rice cold tolerance. Molecular analysis revealed that OsRab11C1 modulates cold tolerance by suppressing the abscisic acid signalling pathway and proline biosynthesis. Using RDP II and GWAS, we identified four qCTBs that are involved in CTB and determined the function of the candidate gene OsRab11C1 in cold tolerance. Our results demonstrate that OsRab11C1 is a negative regulator of cold tolerance and knocking out of the gene by genome-editing may provide enhanced cold tolerance in rice.Cold tolerance at the bud burst stage (CTB) is a key trait for direct-seeded rice. Although quantitative trait loci (QTL) affecting CTB in rice have been mapped using traditional linkage mapping and genome-wide association study (GWAS) methods, the underlying genes remain unknown. In this study, we evaluated the CTB phenotype of 339 cultivars in the Rice Diversity Panel II (RDP II) collection. GWAS identified four QTLs associated with CTB (The online version contains supplementary material available at 10.1186/s12284-021-00538-0. Oryza sativa L.), a major food resource for humans, grows in tropical to temperate regions worldwide. Cold stress is one of the environmental restrictions that most strongly influences rice growth and development, especially at the early seedling and reproductive stages . Traditional linkage mapping and genome-wide association study (GWAS) approaches have identified more than 60 LTG-related QTLs and 40 CTB-associated QTLs  may be involved in the pathway regulating cold tolerance in rice  maps and diverse rice germplasm resources, GWAS has become an established strategy for efficient and high-throughput gene identification in rice  have been identified, hence the genetic basis and underlying molecular mechanism remain poorly understood. In the present study, we performed GWAS using the 339 RDP II cultivars , 22 temperate japonica (TEJ), 88 tropical japonica (TRJ), 56 aromatic (ARO), 64 aus (AUS), and 7 admixture (ADM) cultivars, and their CTB phenotypes are shown in Additional file qCTBs, we performed GWAS using the CTB phenotypes and the high-density SNP datasets of the 339 rice cultivars. Seventeen significantly associated SNPs [− Log10 ≥ 4.3] were detected  at the OsRab11C1 and qCTB-1–2, we constructed a linkage disequilibrium (LD) map for 200 kb region of OsRab11C1, which showed the SNP-1.27301128 (LOD = 0.08) locating in OsRab11C1 was not associated with qCTB-1-2  in the promoter and coding regions of OsRab11C1 between cold-tolerant and cold-sensitive cultivars  in cold-tolerant cultivars to valine (V) in cold-sensitive cultivars, which may affect gene/protein function. These results implicated OsRab11C1 as a strong candidate gene for qCTB-1-2.To confirm the association between OsRab11C1 expression pattern under cold treatment. We performed a quantitative real-time PCR (qRT-PCR) assay using total RNA isolated from seedlings of cold-tolerant cultivar NPB and cold-sensitive cultivar 896 (“JUMA” in the aus subgroup from Bangladesh) sampling at 0, 6, 12, 24, 48 and 72 h after 4 °C cold treatment. As shown in Fig. OsRab11C1 was not altered significantly in NPB, but was strongly induced in 896. This result is consistent with that from genetic analysis showing that OsRab11C1 is a negative regulator of rice cold tolerance described below. To investigate the tissue specificity of OsRab11C1 gene expression, we also probed the expression of OsRab11C1 in nine different tissues and found that OsRab11C1 was highly expressed in roots , OsRab11C1 was predicted to be mainly localized in the cytoplasm. To confirm this, we cloned the OsRab11C1 coding region from NPB into the pYBA1132-GFP (green fluorescent protein) vector and transfected the OsRab11C1-pYBA1132-GFP construct into rice protoplasts of NPB. The results show that OsRab11C1-GFP was co-localized with red fluorescent protein (RFP) in the entire rice cell  in the NPB background using the CRISPR/Cas9  gene editing system. The guide RNA (gRNA) is located at position 102–123 bp in the coding region of OsRab11C1. We sequenced the gRNA targeted region and selected two T0 plants (CR-6 and CR-15) containing insertions and deletions in the target region for subsequent phenotype analysis  under the control of the maize ubiquitin promoter in the NPB background. The relative expression level of OsRab11C1 in the two overexpression lines (OX-23 and OX-44) were 177- and 400-fold higher than that in NPB, respectively  NPB plants, but not statistically different  in OsRab11C1-OE and knockout mutants, and WT plants, using qRT-PCR. These genes are critical for ABA signal transduction under cold stress  are from Asian countries such as Bangladesh and the Philippines, and four are from South American countries including Brazil and Columbia. These varieties can be directly used as parental lines in genetic crosses in local breeding programs. Therefore, our study has provided valuable cold tolerance materials for both indica and japonica rice breeding programs.qCTBs identified in this study, qCTB-1-1 is co-localised with known cold tolerance gene Osa-miR319b  of OsRab11C1 in cold signalling transduction. COLD1 interacts with the G-protein α subunit to activate the Ca2+ channel to sense low temperature and accelerate G-protein GTPase activity . The 700K SNP dataset of the 339 RDP II cultivars was generated from a previous study  = number of seedlings/number of buds × 100)  ≥ 4.3 − log10(1/M) = 4.3,  were considered to be significant association . Gene-specific primers were designed for cloning OsRab11C1 from cultivars that were highly cold tolerant and highly cold sensitive. DNA sequencing of the cloned genes was performed by Sangon Biotech Company . Sequence alignment was performed with SeqMan (http://seqman.software.informer.com/). All primers used in the study are shown in Additional file The full-length sequence, from − 2000 bp upstream of the 5’-untranslated region (UTR) to + 1000 bp downstream of the 3’-UTR of OsRab11C1, total RNA was extracted from root, coleoptile and leaf tissues collected from three seeds of each cultivars using an RNA extraction kit . First-strand cDNA synthesis was performed using HiScript II QRT SuperMix . Gene expression levels were calculated based on analysis of variance (ANOVA) of three technical replicates. The OsUbq gene (LOC_Os03g61970) was included as an internal control. Three independent replicates were performed. Gene-specific primers for OsRab11C1 are shown in Additional file For analysis of the expression pattern and tissue specificity of LOC_Os03g1970 was http://skl.scau.edu.cn/primerdesign/) and the target mutation types were analysed on the website (http://skl.scau.edu.cn/dsdecode/). CRISPR constructs were transformed into NPB using an agrobacterium-mediated transformation method   with or without 4 °C cold treatment were homogenised in 2 ml of 3% aqueous sulfosalicylic acid using liquid nitrogen. Acid ninhydrin, methylbenzene, and glacial acetic acid were added and samples centrifuged. The free proline content was measured using a spectrophotometer as described previously  of NPB and Additional file 1: Table S1.Survival rate of 339 RPD II cultivars at the bud burst stage after cold treatment.Additional file 2: Table S2.List of 41 highly cold tolerant cultivars at the bud burst stage.Additional file 3: Table S3.List of SNPs significantly associated with CTB.Additional file 4: Table S4.List of four QTLs related to CTB.Additional file 5: Table S5.Association of the qCTB1-2-associated significant SNPs in 10 cold tolerant and 10 sensitive rice cultivars.Additional file 6: Table S6.Primers used in this study.


Few studies have investigated the neuropsychological profile of Hearing Loss (HL) subjects and the effects of hearing-aid on cognitive decline. We investigated the neuropsychological profile of HL patients at baseline and compared the neuropsychological profiles of patients with and without hearing-aid at 6 month. Fifty-six HL patients and 40 healthy subjects (HC) underwent neuropsychological and behavioral examination and were compared at baseline. Changes at follow-up were compared between HL patients with (N = 25) and without (N = 31) hearing-aids. At baseline, significant differences between HL and HC were found in MOCA test, Raven's Coloured Progressive Matrices (CPM) and SF-36. Among mild-HL patients, patients with hearing-aid significantly improved on the Clock Drawing Test (CDT) as compared to patients without hearing-aid. Our findings indicate that hearing loss is associated with both a reduced efficiency of the global cognitive state and a worse quality of life as compared to HC, supporting the association between HL and cognitive impairment. Moreover, only patients with mild-HL shows some cognitive improvement after using hearing-aid, suggesting that rehabilitative strategies may be more effective to delay cognitive decline in such patients. However, we cannot exclude that hearing-aids may affect cognitive decline in more severe-HL, but a longer follow-up is needed. HL causes difficulties in both professional and social life, as well as stigmatization. It is estimated that, by 2025, 900 million people throughout the world will be hearing-impaired3.Hearing loss (HL) is characterized by poor speech perception and understanding, especially in noisy settings that involves 25–30% of individuals between 65 and 74 years5, conflicting results have been reported6. In fact, current evidence cannot confirm a clear causal relationship between HL and cognition, since it’s supposed that auditory deafferentation may be a determinant of cognitive decline, but it’s also possible that HL and cognitive declines hare common underlying pathological processes in older age6. Increasing evidence suggests that hearing loss is associated with a wide range of health issues, higher disease burden, and increased risk for hospitalization7.The relationship between auditory and cognitive functioning in the elderly has been the subject of many studies and, although many cross-sectional or longitudinal cohort studies found an association between hearing loss and cognitive decline or dementia8. In particular, HL patients showed a greater risk of developing dementia and a global decrease of cognitive performances10. Attention and processing speed are the most affected functions in HL patients, that appear to need more resources to complete the tasks11 but also auditory-verbal memory is affected in HL12. Various hypotheses have been proposed to explain cognitive decline associated with hearing impairment. HL and cognitive decline may have a common neuropathological origin but it is also possible that hearing loss alone could promote deficits in different areas or interact with other risk factors accelerating cognitive decline8. Usually, HL seems to speed up cognitive decline through the combination of social and sensory isolation and through an increased cognitive load13. Indeed, peripheral HL decreases local cerebral blood flow in primary auditory cortex14 and it is associated with decreased volumes in the auditory cortex, temporal lobe and whole brain, and also with a functional reorganization of the auditory cortical networks, consistent with more demanding listening and a reduction of cognitive reserve13. Furthermore, a reduction of perfusion in primary auditory cortex has been found by ASL-MRI in patients affected by HL in the early stages, suggesting that there is a relationship between HL and cortical activation/metabolism, even if no atrophy was found14.On the other hand, recent studies showed that reduced auditory input due to a hearing impairment is also associated with greater declines in cognitive function in older adults15. Differences in administered tests, sample selection variables and, protocols for the use of aids also led to heterogeneous results15.Comprehensive hearing rehabilitative interventions, that incorporate the use of sensory aids (hearing aids) and rehabilitative counseling to maximize the audibility of speech signals and reduce the cognitive load, provide increased auditory stimulation, and promote social engagement. However, only few studies have investigated the effects of hearing rehabilitative interventions on cognitive decline in HL patients. Specifically, the tests used so far to measure cognitive deficits in HL patients are very heterogeneous and only recently more complete neuropsychological batteries have been used on large samples0) and (2) to compare the neuropsychological profiles of patients with and without hearing aid at 6 month-FU (T1).Therefore, the purposes of the present study were (1) to comprehensively investigate the neuropsychological profile of patients with HL at baseline  consecutive patients diagnosed with HL (mean + SD PTA threshold: 51.18 + 13.38 dB), and 40 healthy subjects (HC), matched for age and education, were recruited at the S. Giovanni di Dio and Ruggi D’Aragona Hospital, Salerno, Italy, between September 2018 and November 2019.Inclusion criteria were the following: patients older than 55 years without dementia, which was evaluated by Mini-Mental State Examination (MMSE) (correct score < 23.8).Exclusion criteria of recruitment in the study were the following: (i) stroke or other neurological disorders; (ii) global cognitive impairment; (iii) major psychiatric disorders; (iv) other causes of hearing loss different from presbycusis ; (v) patients using hearing aids and (vi) other causes of significant disability.12. Given the reduced sample size of the PTA-groups, also divided between with and without aids, we have combined 3 patients with PTA-profound  with patients with PTA-severe.All the audiological evaluations were carried out by an experienced audiologist in a double wall sound proof room. Air conduction pure tone audiometric hearing thresholds were evaluated at 0.125, 0.25, 0.5, 1, 2, 3, 4, 6 and 8 kHz for each subject in both ears using a clinical audiometer . In addition, in order to rule out conductive hearing loss, bone conduction thresholds were measured at 0.25, 0.5, 1, 2, 3 and 4 kHz. All audiometric data presented in the present work refer to air conduction thresholds. The Pure Tone Average (PTA) was calculated ad mean of pure tone thresholds at 0.5, 1, 2 and 4 kHz for each subject in both ears. Hearing impairment was ranked based on PTA as mild, moderate, severe, or profound as follows: mild loss, 26–40 dB; moderate loss, 41–70 dB; and severe loss, 71–90 dB, profound, 90+Twenty-five patients were compliant and accepted to use hearing aids, as prescribed by the audiologists (otolaryngologist), whereas the remaining 31 patients did not accept to wear hearing aids. Neuropsychological and emotional-behavioral examination was repeated in patients with and without hearing aids at 6-month follow-up.6.We choose a battery of tests aimed to reduce confounding factors possibly overestimating the strength of the association between HL and cognitive deficit16, it is recommended for subjects with deafness. Specifically, the CPM has classically been used to measure global cognitive performance (in terms of intelligence)17, mental age18, intellectual performance19 and non-verbal intelligence20, or to measure visuo-perceptual and visuo-spatial functions21. Moreover, studies of brain activity or structure suggest frontal involvement in CPM performance20.The neuropsychological battery included the Montreal Cognitive Assessment (MOCA) to investigate the global cognitive state. In order to analyses the other cognitive functions we used the Digit Cancellation Test (DCT) and the Trail Making Test-part A (TMT-A), The Rey’s auditory 15-word learning test to assess verbal immediate recall and verbal delayed recall (15-RAWLT),the Rey-Osterrieth Complex Figure Test memory (ROCF memory) ,and copy (ROCF copy) and the Clock Drawing Test (CDT). Finally, we used the Raven's Coloured Progressive Matrices (CPM) as screening and executive function test, since, as suggested by Spreen and StraussIn order to investigate the quality of life and the presence of emotional disorders, such as depression and apathy, Short Form 36 (SF-36), Beck Depression Inventory II  and Dimensional Apathy Scale (DAS) were administered.The study was conducted in accordance with the Declaration of Helsinki. All people provided informed consent before being included in the study. The protocol was approved by the competent local committee in charge of guaranteeing the protection of the subjects, such as Campania-South Ethics Committee.Normality test was conducted for demographic, neuropsychological and behavioral variables.An exploratory factor analysis, with Varimax’ rotation statistical technique, was conducted in order to combine the constructs related to the proposed neuropsychological battery and we conducted exploratory post-hoc power analysis for each factor to evaluate the sample size.Patients were compared with HC for demographic and neuropsychological data at baseline by Mann–Whitney U test, corrected for multiple comparisons.1 and T0 were calculated (Delta = T1 – T0) and compared between patients with and without hearing aids using Mann–Whitney's U test. Significant results obtained from the exploratory analysis were then corrected for multiple comparisons.We assessed the relationship between depression and quality of life (QoL) at baseline in HL patients by Spearman’s correlation analysis. Changes in neuropsychological and behavioral scores between TWe also used the Mann–Whitney’s U test to compare neuropsychological and behavioral parameters at baseline and changes at follow up between HL patients with and without hearing aid divided according to the level of hearing impairment.All coauthors agreed with the contents of manuscript. The submission is not under review at any other publication. The study with human subjects was conducted in accordance with the Declaration of Helsinki. All people provided informed consent before being included in the study. The protocol was approved by the competent local committee in charge of guaranteeing the protection of the subjects, such as Campania-South Ethics Committee.According to exploratory factor analysis, there were three latent factors underlying the neuropsychological tests. The first factor explained the 46% of the cumulative variance, the first and second factors explained 61% of the cumulative variance and the three factors together explained 72% of the cumulative variance. We defined the first factor “executive/ attentional factor”, the second one as “memory factor” and the third one as “visuo-spatial factor”  Table .Table 1DA significant difference was found between the two groups in the following tests: MOCA-total score (p = 0.004), CPM p = 0.001), SF-36 bodily pain (p = 0.004), SF-36 general health perception (p = 0.001), SF-36 Emotional wellbeing (p = 0.001) and SF-36 mental health (p < 0.001), with all average values resulting higher in HC compared to patients. Therefore, HL had worse performances on cognitive tests and a worse quality of life .After the exploratory analysis, significantly different changes (T1 − T0) were found between patients with and without hearing aid on the CPM p = 0.002), the ROCF (p = 0.032), the DAS-Total (p = 0.016) and DAS-emotional (p = 0.048). In particular, patients with hearing aid improved on the ROCF and DAS and worsened on the CPM, as compared to patients without hearing aid, but after correcting for multiple comparisons only CPM differences were still significant between groups  as compared to patients without hearing aid. Among patients with moderate HL, patients with hearing aid showed a trend towards a significant improvement on ROCF memory (p = 0.065), but worsened on CPM as compared to patients without hearing aid (p = 0.038). Among patients with severe-profound HL, patients with hearing aid significantly improved on DAS (p = 0.032), while worsening on CPM (p = 0.027) as compared to patients without hearing aid , used to analyze attention or global cognitive status, and found that greater hearing loss was significantly associated with lower DSST scores. As for attention, we used Digit Cancellation Test (DCT) and the Trail Making Test-part A (TMT-A) to measure task-switching and information processing speed and selective attention but we found no significant differences; this may depend on the size of the sample and the type of specific function studied.Lin et al.Finally, in the previous literature memory and executive constructs were usually affected in HL patients , such as pain, emotional wellbeing, general health, and mental health, as previously reported39. Polku et al.38 found that only perceived hearing difficulty factors, as assessed using a 16-item questionnaire sent by post, and not objective HL severity as assessed by pure tone audiometry, were significantly associated with lower scores on total and all QoL domains, assessed by the short version of the 26-item World Health Organization Quality of Life Assessment. Hyams et al.39 evaluated 30 HC, 33 hearing impaired subjects without hearing aids, and 37 hearing impaired subjects with hearing aids using the Short Form-36 and found that subjects without hearing aids had significantly lower QoL than those without hearing aids. hearing impaired with hearing aids and HC. In the elderly population with HL, up to 20% of subjects report a clinically relevant level of depressive symptoms that would require treatment40. Both cross-sectional and longitudinal studies indicate that HL is related to the increase in depressive symptoms, although the strength of the association varies between studies. Several methodological differences, such as age at enrollment, severity of HL, and the scales used for assessing depression, may explain this heterogeneity. Overall, however, we indicate an association between HL and reactive depressive symptoms, but not with respect to the scale of apathy40. Specifically, we found that some HL patients crossed the limit of the scale (26%), with only 8% of HC exceeding the limit. Due to the strong negative correlation between depression and quality of life in our HL patients, we assume that there is a relationship between these two variables, which deserves to be investigated.Since the auditory system features an intense efferent and afferent traffic due to mutual interactions between cortical, brain stem and peripheral pathways, the impact of hearing loss on cognitive decline should be considered as dependent on both central and peripheral factors41 which is compensated by a strengthening of executive functions, patients without hearing aids may have needed more executive resources, such as logical reasoning, to compensate for long-term memory loss. Moreover, the different change at follow up in abstract logical reasoning might also be explained according to the hypothesis of relocation of cognitive resources, suggesting that in HL there is a concomitant increased engagement of short-term memory and executive functions42.At baseline HL patients that refused the hearing aids were more apathetic, mostly on the emotional domain of apathy, than those who accepted hearing aids. At follow-up, patients with hearing aids worsened on abstract logical reasoning and according to an exploratory analysis without correction for multiple comparisons, they improved on long-term spatial memory and apathy as compared to patients not wearing hearing aid. We decided to explain also the exploratory results and we suggest that since HL leads to a progressive disuse of long-term memory43. According to this hypothesis, the effects of hearing impairment on cognitive networks may be extensive, but also temporary and reversible, thus suggesting that a longer follow up of our patients would be needed to evaluate the long-term effect of hearing aids on cognitive abilities43.Our patients with hearing aids showed an improvement in long-term spatial memory, that can be explained according to the hypothesis of information degradation. Indeed, since HL increases the cognitive load in the auditory processing of information thus compromising the perception phase, it is supposed that other brain networks are recruited to overcome such difficulties4. Indeed, the literature on the use of hearing aids gave mixed results. In fact, some studies found an improved cognitive performance in HL patients after aids use46 while other studies found that the use of long-term amplification tools had no effect on cognition and cognitive decline47. In particular, Sarant et al.15 assessed ninety-nine HL patients by Mini Mental State (MMSE) and CogState battery at baseline and after using hearing aids for 18 months, and found that at follow-up patients improved in speech perception in quiet environments, self-reported listening disability and quality of life. Moreover, at 18-month follow-up with hearing aids, they found either a clinically significant improvement or stability in executive function in 97.3% of participants using hearing aids, and either stability or significant improvement in global cognition, suggesting that treatment of hearing loss with hearing aids may delay cognitive decline15.Other previous studies, performed on very large samples but using only screening tests for cognition, found that patients with hearing aids had a better performance than patients without aids on screening tests, usually the MMSE48.Since the association between HL and cognitive deficits may have different pathogenic mechanisms, also the effects of hearing aids on cognition could have different explanations. In fact, auditory and cognitive deficits may have the same neuropathological origin, or HL could lead to a multi-morbidity cycle in different brain areas or interact with other risk factors to accelerate cognitive decline11 performed a systematic review and meta-analysis including 33 studies, and reported that hearing impairment seemed to negatively affect all cognitive domains, while any type of hearing intervention significantly improved cognition, but they also suggested that their results were not conclusive, due to differences among studies, small sample sizes, and the failure to control for premorbid and other health factors in most studies.Taljaard et al.47 did not find any significant differences at MOCA screening test among HL patients with hearing aids (N = 22), HL patients without aids (N = 20) and HC (N = 19). Moreover, a study on community-dwelling older adults with hearing impairment (N = 666) found no significant differences between hearing aid users and non-users in cognitive, social engagement or mental health outcomes assessed by means of MMSE, TMT, DSST, Auditory Verbal Learning Test (AVLT) and the Verbal Fluency Test (VFT) at baseline, 5 years prior to baseline and 5 and 11 years after baseline49.On the other hand, in a cross-sectional study, Saunders et al.50. On the other hand, among patients with moderate or severe-profound HL, abstract logical reasoning tended to worsen in patients with hearing aids as compared to patients without aids, suggesting that patients without hearing aids may have needed more executive resources, as already discussed for the whole sample, and that the location of cognitive resources may affect patients with moderate or severe profound HL more than patients with mild HL.In our study, among patients with mild HL, patients with hearing aid significantly improved on the CDT as compared to patients without hearing aids; although CDT investigated the visuo-spatial abilities, it can also be used to evaluate global cognitive state. This finding suggests that mild HL responds well to HL treatment on a short-term follow up. Indeed, the CDT is scarcely affected by the level of education, language and cultural differences than the other cognitive tests such as the MMSE and is also less affected by voice delivery; it covers a wide range of cognitive domains such as construction, visuo-spatial function, conceptualization and the executive function, and it is particularly informative since it involves the visuo-spatial function as well as the frontal inhibitory functionHowever, our subgroups were too small to draw firm conclusions. We can only speculate that long-term HL treatment in mild HL patients could favor a lower cognitive decline over time, but this hypothesis needs to be supported by further longitudinal studies assessing cognitive outcomes also according to the severity of HL.22.The beneficial effects of hearing aid use on cognitive function are likely modest; therefore, it is necessary to confirm the effects through further investigations that involve larger sample sizes and long-term observationThe main limitation of this study is the small number of patients involved, that justified a more exploratory approach. Second, the interviewer was not blind to the diagnosis and the use of hearing aids; instead, the data was collected blindly to specific hypotheses under consideration. Third, the evaluation was conducted using a large number of neuropsychological tests, based on the Guidelines for the evaluation of dementia and age-related cognitive change, this allowed to perform a more complete analysis, but indeed increased the number of comparisons. We acknowledge that further studies on larger populations are warranted to fully explain our mixed findings on tasks exploring the same cognitive domains. Furthermore, as regards the tests, although they were chosen keeping low the hearing load, tests made for hearing impaired were not exclusively used. Finally, the brief follow up may have conditioned the reduced significance of the tests.In conclusion, due to the prominent cognitive and social consequences, HL should be considered a social emergency. Due to the increasing prevalence of HL, associated with increasing age of the population, research into the mechanistic pathways linking HL with dementia and the potential of rehabilitative strategies to mitigate this association is warranted. The study of the cognitive profile of hearing-impaired subjects is also important, since it can contribute to a better understanding of the predictive factors of cognitive decline in the adulthood and, therefore, it is necessary to continue studying these groups of patients over time, increasing the exposure times of the subjects to the aids itself. An extensive interdisciplinary collaboration among audiologists, neurologists and neuropsychologists is deserved for future studies.Supplementary Information.