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It is supposed that the subterranean lifestyle in mammals is reflected in ear morphology and tuning of hearing to low frequencies. We studied two root-rat species to see if their ear morphology reflects the difference in the amount of their surface activity. Whereas the more subterranean Tachyoryctes splendens possesses shorter pinnae as expected, it has smaller bullae compared to the more epigeic Tachyoryctes macrocephalus. The ratio between the eardrum and the stapedial footplate area and the ratio between the mallear and the incudal lever were lower in T. splendens (19.3 ± 0.3 and 1.9 ± 0.0, respectively) than in T. macrocephalus (21.8 ± 0.6 and 2.1 ± 0.1), probably reflecting the latter's higher surface activity. The cochlea in both species has 3.5 coils, yet the basilar membrane is longer in the smaller T. splendens (13.0 ± 0.5 versus 11.4 ± 0.7 mm), which indicates its wider hearing range and/or higher sensitivity (to some frequencies). In both root-rat species, the highest density of outer hair cells (OHC) was in the apical part of the cochlea, while the highest density of inner hair cells (IHC) was in its middle part. This OHC density pattern corresponds with good low-frequency hearing, whereas the IHC pattern suggests sensitivity to higher frequencies.

Background: For surgical treatment of the face, detailed surgical planning is necessary to avoid later unaesthetic results. Most of the studies in the literature concentrate on the ears' anatomy during childhood and adolescence. Nearly no study evaluates the anatomy of ears of people aged 50 or older. It was our aim to measure and evaluate the ear's anatomy in Caucasians between the ages of 21 and 65., Methods: Three-dimensional scans of 240 volunteers were taken. The subjects were divided into groups of males and females and each of them into three groups by age (21-35, 36-50, 51-65). Landmarks were placed in these scans. Distances, relations and angles between them were recorded., Results: The distance between the subaurale and superaurale significantly increases (p < 0.001) during the aging process in males and females. Also, the width of the ear, measured between the preaurale and postaurale, significantly increased (p = 0.007) with advancing age. When the length of the ear is divided into four parts by anatomical landmarks, it extended the most in the lower quadrant with increasing subject age., Conclusion: The ear of Caucasians does not stop changing its shape during adulthood. Even after the body has stopped growing, the ear still does. With the measured values in this study, it should be possible for the surgeon to plan the operation in advance and achieve satisfactory aesthetic outcomes., Level of Evidence V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Context: Maize is a major crop in Italy and is constantly affected by the fungus Fusarium verticillioides , producing ear rot and grain contamination by fumonisins. Finding new genotypes resistant to Fusarium infection is an important goal for the improvement of maize cultivation. Aims: The objective of this work was to test a collection of 33 traditional landraces from the Emilia-Romagna (Italy) region for Fusarium ear rot (FER) severity, fumonisin content, and their agronomic performance. Methods: Primary ears were artificially inoculated with a toxigenic strain of F. verticillioides in a 2-year experimental trial. The landrace 'Nostrano di Storo' and a commercial hybrid of FAO maturity class 300 were also included and used as comparisons representing a well-known and highly valued landrace and a modern flint hybrid, respectively. Key results: The collection showed great phenotypic variability for all the agronomic traits assessed and responded differently to the Fusarium infection with percentages of FER ranging from 6.6% to 49.3%, and fumonisins from 4.3 mg/kg to 34.5 mg/kg. Thirteen and six landraces displayed FER percentages and fumonisin content very similar to the hybrid, respectively. Moreover, eight landraces exhibited grain yield values comparable to the hybrid. Interestingly, Va221, Va227 and EMR03 showed the best combination among these three traits. Conclusions: This local material can be considered suitable for breeding purposes targeting the development of FER and fumonisin resistant germplasm. Implications: The collection may represent a resource for future research aimed at evaluating the response to multiple pathogens and their associated mycotoxins. Finding new genotypes resistant to Fusarium infection represents an important goal for the improvement of maize cultivation. In this regard, a collection of maize landraces deriving from Emilia-Romagna (Italy) region was studied. These landraces represent starting resources crucial for broadening the genetic bases of maize and introducing new resistant alleles useful in breeding programs targeting multiple pathogens and their associated mycotoxins. [ABSTRACT FROM AUTHOR]

The performance of maize hybrids largely depend on two parental inbred lines. Improving inbred lines using artificial selection is a key task in breeding programs. However, it is important to elucidate the effects of this selection on inbred lines. Altogether, 208 inbred lines from two maize heterosis groups, named Shaan A and Shaan B, were sequenced by the genotype-by-sequencing to detect genomic changes under selection pressures. In addition, we completed genome-wide association analysis in 121 inbred lines to identify candidate genes for ear morphology related traits. In a genome-wide selection scan, the inbred lines from Shaan A and Shaan B groups showed obvious population divergences and different selective signals distributed in 337 regions harboring 772 genes. Meanwhile, functional enrichment analysis showed those selected genes are mainly involved in regulating cell development. Interestingly, some ear morphology related traits showed significant differentiation between the inbred lines from the two heterosis groups. The genome-wide association analysis of ear morphology related traits showed that four associated genes were co-localized in the selected regions with high linkage disequilibrium. Our spatiotemporal pattern and gene interaction network results for the four genes further contribute to our understanding of the mechanisms behind ear and fruit length development. This study provides a novel insight into digging a candidate gene for complex traits using breeding materials. Our findings in relation to ear morphology will help accelerate future maize improvement. [ABSTRACT FROM AUTHOR]

The use of a microwave scattering model is fundamental to rice monitoring by synthetic aperture radar (SAR), and an ear scattering model is necessary to improve the accuracy of the microwave scattering model of the rice field. A novel rice ear scattering model, the multisphere ear scattering model, was developed by incorporating the microstructure of rice ear panicles, including the ear grain parameters in particular. A virtual ear model was used to simulate the ear morphology, and a multisphere scattering model was used to simulate the ear scattering. The multisphere ear scattering model has the potential to retrieve grain parameters from SAR imagery. The new model was also compared with a traditional two-cylinder ear model; the large discrepancy in the simulation results shows the necessity of carrying out a verification experiment. [ABSTRACT FROM PUBLISHER]

Background: The domestic dog is a rich resource for mapping the genetic components of phenotypic variation due to its unique population history involving strong artificial selection. Genome-wide association studies have revealed a number of chromosomal regions where genetic variation associates with morphological characters that typify dog breeds. A region on chromosome 10 is among those with the highest levels of genetic differentiation between dog breeds and is associated with body mass and ear morphology, a common motif of animal domestication. We characterised variation in this region to uncover haplotype structure and identify candidate functional variants. Results: We first identified SNPs that strongly associate with body mass and ear type by comparing sequence variation in a 3 Mb region between 19 breeds with a variety of phenotypes. We next genotyped a subset of 123 candidate SNPs in 288 samples from 46 breeds to identify the variants most highly associated with phenotype and infer haplotype structure. A cluster of SNPs that associate strongly with the drop ear phenotype is located within a narrow interval downstream of the gene MSRB3, which is involved in human hearing. These SNPs are in strong genetic linkage with another set of variants that correlate with body mass within the gene HMGA2, which affects human height. In addition we find evidence that this region has been under selection during dog domestication, and identify a cluster of SNPs within MSRB3 that are highly differentiated between dogs and wolves. Conclusions: We characterise genetically linked variants that potentially influence ear type and body mass in dog breeds, both key traits that have been modified by selective breeding that may also be important for domestication. The finding that variants on long haplotypes have effects on more than one trait suggests that genetic linkage can be an important determinant of the phenotypic response to selection in domestic animals. [ABSTRACT FROM AUTHOR]