Brain Abnormalities in Patients with Germline Variants in H3F3: Novel Imaging Findings and Neurologic Symptoms Beyond Somatic Variants and Brain Tumors.

BACKGROUND AND PURPOSE: Pathogenic somatic variants affecting the genes Histone 3 Family 3A and 3B (H3F3) are extensively linked to the process of oncogenesis, in particular related to central nervous system tumors in children. Recently, H3F3 germline missense variants were described as the cause of a novel pediatric neurodevelopmental disorder. We aimed to investigate patterns of brain MR imaging of individuals carrying H3F3 germline variants. MATERIALS AND METHODS: In this retrospective study, we included individuals with proved H3F3 causative genetic variants and available brain MR imaging scans. Clinical and demographic data were retrieved from available medical records. Molecular genetic testing results were classified using the American College of Medical Genetics criteria for variant curation. Brain MR imaging abnormalities were analyzed according to their location, signal intensity, and associated clinical symptoms. Numeric variables were described according to their distribution, with median and interquartile range. RESULTS: Eighteen individuals (10 males, 56%) with H3F3 germline variants were included. Thirteen of 18 individuals (72%) presented with a small posterior fossa. Six individuals (33%) presented with reduced size and an internal rotational appearance of the heads of the caudate nuclei along with an enlarged and squared appearance of the frontal horns of the lateral ventricles. Five individuals (28%) presented with dysgenesis of the splenium of the corpus callosum. Cortical developmental abnormalities were noted in 8 individuals (44%), with dysgyria and hypoplastic temporal poles being the most frequent presentation. CONCLUSIONS: Imaging phenotypes in germline H3F3-affected individuals are related to brain features, including a small posterior fossa as well as dysgenesis of the corpus callosum, cortical developmental abnormalities, and deformity of lateral ventricles.

Characterization of tissue types in basal cell carcinoma images via generative modeling and concept vectors.

The promise of machine learning methods to act as decision support systems for pathologists continues to grow. However, central to their successful adoption must be interpretable implementations so that people can trust and learn from them effectively. Generative modeling, most notable in the form of adversarial generative models, is a naturally interpretable technique because the quality of the model is explicit from the quality of images it generates. Such a model can be further assessed by exploring its latent space, using human-meaningful concepts by defining concept vectors. Motivated by these ideas, we apply for the first time generative methods to histological images of basal cell carcinoma (BCC). By simultaneously learning to generate and encode realistic image patches, we extract feature rich latent vectors that correspond to various tissue morphologies, namely BCC, epidermis, keratin, papillary dermis and inflammation. We show that a logistic regression model trained on these latent vectors can achieve high classification accuracies across 6 binary tasks (86-98%). Further, by projecting the latent vectors onto learned concept vectors we can generate a score for the absence or degree of presence for a given concept, providing semantically accurate "conceptual summaries" of the various tissues types within a patch. This can be extended to generate multi-dimensional heat maps for whole-image specimens, which characterizes the tissue in a similar way to a pathologist. We additionally find that accurate concept vectors can be defined using a small labeled dataset.

Regenerative medicine for end-stage fibrosis and tissue loss in the upper aerodigestive tract: a twenty-first century review.

OBJECTIVE: This review assesses regenerative medicine of the upper aerodigestive tract during the first two decades of the twenty-first century, focusing on end-stage fibrosis and tissue loss in the upper airways, salivary system, oropharynx and tongue. METHOD: PubMed, Embase, Google Scholar, Cochrane Library, Medline and clinicaltrials.org were searched from 2000 to 2019. The keywords used were: bioengineering, regenerative medicine, tissue engineering, cell therapy, regenerative surgery, upper aerodigestive tract, pharynx, oropharynx, larynx, trachea, vocal cord, tongue and salivary glands. Original studies were subcategorised by anatomical region. Original human reports were further analysed. Articles on periodontology, ear, nose and maxillofacial disorders, and cancer immunotherapy were excluded. RESULTS: Of 716 relevant publications, 471 were original studies. There were 18 human studies included, within which 8 reported airway replacements, 5 concerned vocal fold regeneration and 3 concerned salivary gland regeneration. Techniques included cell transplantation, injection of biofactors, bioscaffolding and bioengineered laryngeal structures. CONCLUSION: Moderate experimental success was identified in the restoration of upper airway, vocal fold and salivary gland function. This review suggests that a shift in regenerative medicine research focus is required toward pathology with a higher disease burden.

Development of a genome-wide InDel marker set for allele discrimination between rice (Oryza sativa) and the other seven AA-genome Oryza species.

Wild relatives of rice in the genus Oryza (composed of 24 species with 11 different genome types) have been significantly contributing to the varietal improvement of rice (Oryza sativa). More than 4000 accessions of wild rice species are available and they are regarded as a "genetic reservoir" for further rice improvement. DNA markers are essential tools in genetic analysis and breeding. To date, genome-wide marker sets for wild rice species have not been well established and this is one of the major difficulties for the efficient use of wild germplasm. Here, we developed 541 genome-wide InDel markers for the discrimination of alleles between the cultivated species O. sativa and the other seven AA-genome species by positional multiple sequence alignments among five AA-genome species with four rice varieties. The newly developed markers were tested by PCR-agarose gel analysis of 24 accessions from eight AA genome species (three accessions per species) along with two representative cultivars (O. sativa subsp. indica cv. IR24 and subsp. japonica cv. Nipponbare). Marker polymorphism was validated for 475 markers. The number of polymorphic markers between IR24 and each species (three accessions) ranged from 338 (versus O. rufipogon) to 416 (versus O. longistaminata) and the values in comparison with Nipponbare ranged from 179 (versus O. glaberrima) to 323 (versus O. glumaepatula). These marker sets will be useful for genetic studies and use of the AA-genome wild rice species.

Diagnostic utility of additional whole-chest CT as part of an acute abdominal pain CT imaging pathway during the COVID-19 pandemic.

AIM: To evaluate the diagnostic utility of additional whole-chest computed tomography (CT) in identifying otherwise unheralded COVID-19 lung disease as part of an acute abdominal pain CT imaging pathway in response to the COVID-19 pandemic. MATERIALS AND METHODS: Consecutive patients (n=172) who underwent additional whole-chest CT via a COVID-19 acute abdominal pain CT imaging pathway between 27 March and 3 May 2020 were evaluated in this retrospective single-centre study. Chest CT examinations were graded as non-COVID-19, indeterminate for, or classic/probable for COVID-19. CT examinations in the latter two categories were further divided into one of three anatomical distributions (lung base, limited chest [below carina], whole chest [above carina]) based on location of findings. Reverse transcriptase-polymerase chain reaction (RT-PCR) results and clinical features of COVID-19 were assessed to determine if COVID-19 was clinically suspected at the time of CT referral. RESULTS: Twenty-seven of the 172 (15.7%) patients had CT features potentially indicative of COVID-19 pneumonia, 6/27 (3.5%) demonstrating a classic/probable pattern and 21/27 (12.2%) demonstrating an indeterminate pattern. After correlation with clinical features and RT-PCR 8/172 (4.7%) were defined as COVID-19 positive, of which only 1/172 (0.6%) was clinically unsuspected of COVID-19 at the time of CT referral. All COVID-19 positive cases could be identified on review of the lung base alone. CONCLUSION: Whole-chest CT as part of an acute abdominal pain CT imaging pathway has a very low diagnostic yield for our cohort of patients. All COVID-19-positive patients in our cohort were identified on review of the lung bases on the abdominal CT and this offers an alternative imaging approach in this patient group.

A platinum standard pan-genome resource that represents the population structure of Asian rice.

As the human population grows from 7.8 billion to 10 billion over the next 30 years, breeders must do everything possible to create crops that are highly productive and nutritious, while simultaneously having less of an environmental footprint. Rice will play a critical role in meeting this demand and thus, knowledge of the full repertoire of genetic diversity that exists in germplasm banks across the globe is required. To meet this demand, we describe the generation, validation and preliminary analyses of transposable element and long-range structural variation content of 12 near-gap-free reference genome sequences (RefSeqs) from representatives of 12 of 15 subpopulations of cultivated Asian rice. When combined with 4 existing RefSeqs, that represent the 3 remaining rice subpopulations and the largest admixed population, this collection of 16 Platinum Standard RefSeqs (PSRefSeq) can be used as a template to map resequencing data to detect virtually all standing natural variation that exists in the pan-genome of cultivated Asian rice.

Development of consensus-based international antimicrobial stewardship competencies for undergraduate nurse education.

BACKGROUND: There is growing recognition by national and international policymakers of the contribution nurses make towards antimicrobial stewardship. Although undergraduate education provides an ideal opportunity to prepare nurses for antimicrobial stewardship roles and activities, only two-thirds of undergraduate nursing programmes incorporate any antimicrobial stewardship teaching and only 12% cover all the recommended antimicrobial stewardship principles. Nurses also report that they do not have a good knowledge of antibiotics, and many have not heard of the term antimicrobial stewardship. AIM: To provide international consensus on the antimicrobial stewardship competency descriptors appropriate for undergraduate nurse education. METHODS: A modified Delphi approach comprising two online surveys delivered to an international panel of 15 individuals reflecting expertise in prescribing and medicines management in the education and practice of nurses; and antimicrobial stewardship. Data collection took place between February and March 2019. FINDINGS: A total of 15 participants agreed to become members of the expert panel, of whom 13 (86%) completed round 1 questionnaire, and 13 (100%) completed round 2. Consensus was achieved, with consistently high levels of agreement across panel members, on six overarching competency domains and 63 descriptors, essential for antimicrobial stewardship practice. CONCLUSION: The competency descriptors should be used to direct undergraduate nurse education and the antimicrobial stewardship practices of qualified nurses (including those working in new roles such as Nursing Associates) due to the high levels of agreement reached on competency descriptors.

Variation in seed longevity among diverse Indica rice varieties.

BACKGROUND AND AIMS: Understanding variation in seed longevity, especially within closely related germplasm, will lead to better understanding of the molecular basis of this trait, which is particularly important for seed genebanks, but is also relevant to anyone handling seeds. We therefore set out to determine the relative seed longevity of diverse Indica rice accessions through storage experiments. Since antioxidants are purported to play a role in seed storability, the antioxidant activity and phenolic content of caryopses were determined. METHODS: Seeds of 299 Indica rice accessions harvested at 31, 38 and 45 d after heading (DAH) between March and May 2015 and differing in harvest moisture content (MC) were subsequently stored at 10.9 % MC and 45 °C. Samples were taken at regular intervals and sown for germination. Germination data were subjected to probit analysis and the resulting parameters that describe the loss of viability during storage were used for genome-wide association (GWA) analysis. KEY RESULTS: The seed longevity parameters, Ki [initial viability in normal equivalent deviates (NED)], -σ-1 (σ is the time for viability to fall by 1 NED in experimental storage) and p50 [time for viability to fall to 50 % (0 NED)], varied considerably across the 299 Indica accessions. Seed longevity tended to increase as harvest MC decreased and to decrease as harvest MC increased. Eight major loci associated with seed longevity parameters were identified through GWA analysis. The favourable haplotypes on chromosomes 1, 3, 4, 9 and 11 enhanced p50 by ratios of 0.22-1.86. CONCLUSIONS: This is the first study to describe the extent of variation in σ within a species' variety group. A priori candidate genes selected based on rice genome annotation and gene network ontology databases suggested that the mechanisms conferring high seed longevity might be related to DNA repair and transcription, sugar metabolism, reactive oxygen species scavenging and embryonic/root development.

Continuous intraoperative nerve monitoring in thyroidectomy using automatic periodic stimulation in 256 at-risk nerves.

INTRODUCTION: Automatic periodic stimulation of the vagal nerve during thyroidectomy provides real-time feedback of recurrent laryngeal nerve function intraoperatively. To assess the validity of this device, the ability of monitoring to predict recurrent laryngeal nerve palsy was determined and the incidence of recurrent laryngeal nerve palsy recorded. MATERIALS AND METHODS: All thyroidectomies using APS® (Automatic Periodic Stimulation, Medtronic) nerve monitoring were reviewed over a 27-month period. Changes in signal amplitude and latency during thyroidectomy were recorded from saved data. Postoperative fibreoptic laryngoscopy determined the incidence of vocal cord immobility and recovery of nerve function was assessed from follow-up letters. RESULTS: A total of 256 at-risk nerves were examined (132 hemi- and 62 total thyroidectomies) in cases involving benign and malignant disease. Permanent recurrent laryngeal nerve palsy occurred in six (2.3%) lobectomies and transient recurrent laryngeal nerve palsy occurred in two lobectomies (< 1%). Sensitivity for detecting postoperative vocal cord immobility was 100% and specificity 85% if the end amplitude was 50% below baseline. The positive predictive value when amplitude was 50% below baseline was 18%. The negative predictive value when amplitude was 50% above or equal to baseline was 100%. Intraoperatively, the amplitude was 50% below baseline more frequently in the vocal cord immobility group (t-test, P < 0.015). No vagal nerve complications occurred. CONCLUSION: Whilst the incidence of recurrent laryngeal nerve palsy is comparable to rates in the literature, the incidence of transient palsy is lower than published averages. APS is able to reliably predict recurrent laryngeal nerve palsy based on end amplitude.

Challenges Faced in Translating the Benefits of Surfactant Replacement Therapy to a Resource-Limited Setting.

Aim To determine the challenges, if any, in translating the benefits of surfactant replacement therapy (SRT) to a resource-limited setting. Method This was a retrospective descriptive study comparing the outcome of 75 cases who received surfactant and 69 controls who did not at the University Hospital of the West Indies during the period 2001 to 2011. Descriptive analyses were performed. Statistical significance was taken at the level p < 0.05. Results Only 13% of neonates with respiratory distress syndrome received surfactant therapy. The median time of surfactant administration was 16.5 hours (interquartile range: 6-37 hours). The mean ± standard deviation time between repeat doses was 19.1 ± 14 hours. There was no difference in mortality between cases (67%) and controls (59%) (p = 0.32). However, the cases who survived were less mature (28.3 ± 2 weeks) and less clinically stable (CRIB II [Clinical Risk Index for Babies] score: 8.2 ± 3) than their controls who survived (30.0 ± 2 weeks; CRIB II score: 6.0 ± 3) (p = 0.01). There was no difference in mean gestational age or CRIB II scores between nonsurviving cases and controls. A high incidence of sepsis, pneumothoraces, and pulmonary hemorrhage was noted in both cases and controls. Conclusion SRT did not improve the overall outcome in preterm neonates treated with RDS. Challenges encountered in optimizing SRT included affordability and accessibility of surfactant, supportive equipment, and supportive therapies, as well as a high incidence of complications related to prematurity.

Use of diagnostic reports to estimate prevalence and distribution of skeletal lesions in young Thoroughbreds.

Diagnostic reports written to assist stud managers in the sale of young Thoroughbreds have not previously been used as a data source for the study of skeletal lesions. However, analyses of these reports may provide efficient and cost-effective insights into the prevalence and distribution of skeletal lesions within a population. Diagnostic reports written by veterinarians were acquired from Thoroughbred stud managers in Australia and New Zealand. The reports were based on approximately 1300 sets of weanling and yearling radiographs taken between 2002 and 2007. The prevalence and anatomical distribution of skeletal lesions in weanlings (299 horses) and yearlings (1004 horses) were determined from these reports. Overall, 69.9% of weanlings and 64.5% of yearlings were reported as having one or more skeletal lesions. Diagnostic reports in weanlings were a strong indication of what was likely to be seen in subsequent yearling reports. These diagnostic reports are typically used by stud managers in the sales process and the potential drawback is that some categories of skeletal lesions may be under-reported. However, there was substantial agreement between the prevalence and distribution of several skeletal lesions reported in this study and those previously reported from direct evaluation of radiographs for Australian and New Zealand Thoroughbred yearlings. Strong agreement was found for osteophytes, enthesiophytes and other modelling in the hocks, and for lesions in the hind fetlocks and stifles. This indicates that written diagnostic reports are a useful and a reliable source of data for the study of some skeletal lesions in young Thoroughbred horses.

Heritability of racing durability traits in the Australian and Hong Kong Thoroughbred racing populations.

REASONS FOR PERFORMING STUDY: Many attempts have been made to improve the well-being of racing Thoroughbreds through improvements in management and veterinary care. However, these attempts are often limited by the industry's ability to regulate a large number of environmental variables and as a result have arguably had limited success in providing long-lasting change for the breed. OBJECTIVES: To identify heritable durability traits for Thoroughbred horses racing in Australia and Hong Kong. STUDY DESIGN: Heritability analysis of a longitudinal dataset. METHODS: Performance data on the Thoroughbred populations racing in Australia and Hong Kong between 2000 and 2011 (n = 168,993) were used to estimate the heritabilities and probability values of fixed effects and covariates for a range of racing durability traits. Heritabilities for all durability traits were estimated using a single trait animal model. Each model included, as a minimum, the effects of sex and trainer. RESULTS: Racing longevity (0.12 ± 0.01), racing persistence (0.10 ± 0.01), racing frequency (0.03 ± 0.01), spells (a time period between consecutive races, official trials and/or jump-outs greater than 90 days in length) per year (0.05 ± 0.01), spells per 10 starts (0.03 ± 0.01) and variation of days between races (0.08 ± 0.03) were all significantly heritable for horses racing in Australia. Racing longevity (0.08 ± 0.02), racing persistence (0.04 ± 0.02), spells per year (0.06 ± 0.02) and spells per 10 starts (0.11 ± 0.04) were significantly heritable for horses racing in Hong Kong. CONCLUSIONS: The heritabilities estimated for durability traits in this study provide support for the successful and practical application of genetic selection methodologies to improving the well-being of racing Thoroughbreds.

Tissue-Engineered Tracheal Replacement in a Child: A 4-Year Follow-Up Study.

In 2010, a tissue-engineered trachea was transplanted into a 10-year-old child using a decellularized deceased donor trachea repopulated with the recipient's respiratory epithelium and mesenchymal stromal cells. We report the child's clinical progress, tracheal epithelialization and costs over the 4 years. A chronology of events was derived from clinical notes and costs determined using reference costs per procedure. Serial tracheoscopy images, lung function tests and anti-HLA blood samples were compared. Epithelial morphology and T cell, Ki67 and cleaved caspase 3 activity were examined. Computational fluid dynamic simulations determined flow, velocity and airway pressure drops. After the first year following transplantation, the number of interventions fell and the child is currently clinically well and continues in education. Endoscopy demonstrated a complete mucosal lining at 15 months, despite retention of a stent. Histocytology indicates a differentiated respiratory layer and no abnormal immune activity. Computational fluid dynamic analysis demonstrated increased velocity and pressure drops around a distal tracheal narrowing. Cross-sectional area analysis showed restriction of growth within an area of in-stent stenosis. This report demonstrates the long-term viability of a decellularized tissue-engineered trachea within a child. Further research is needed to develop bioengineered pediatric tracheal replacements with lower morbidity, better biomechanics and lower costs.

A spatially-averaged mathematical model of kidney branching morphogenesis.

Kidney development is initiated by the outgrowth of an epithelial ureteric bud into a population of mesenchymal cells. Reciprocal morphogenetic responses between these two populations generate a highly branched epithelial ureteric tree with the mesenchyme differentiating into nephrons, the functional units of the kidney. While we understand some of the mechanisms involved, current knowledge fails to explain the variability of organ sizes and nephron endowment in mice and humans. Here we present a spatially-averaged mathematical model of kidney morphogenesis in which the growth of the two key populations is described by a system of time-dependant ordinary differential equations. We assume that branching is symmetric and is invoked when the number of epithelial cells per tip reaches a threshold value. This process continues until the number of mesenchymal cells falls below a critical value that triggers cessation of branching. The mathematical model and its predictions are validated against experimentally quantified C57Bl6 mouse embryonic kidneys. Numerical simulations are performed to determine how the final number of branches changes as key system parameters are varied (such as the growth rate of tip cells, mesenchyme cells, or component cell population exit rate). Our results predict that the developing kidney responds differently to loss of cap and tip cells. They also indicate that the final number of kidney branches is less sensitive to changes in the growth rate of the ureteric tip cells than to changes in the growth rate of the mesenchymal cells. By inference, increasing the growth rate of mesenchymal cells should maximise branch number. Our model also provides a framework for predicting the branching outcome when ureteric tip or mesenchyme cells change behaviour in response to different genetic or environmental developmental stresses.

Heritability of racing performance in the Australian Thoroughbred racing population.

Performance data for 164,046 Thoroughbreds entered in a race or official barrier trial in Australia were provided by Racing Information Services Australia. Analyses estimating the heritability for a range of racing performance traits using a single-trait animal model were performed using ASREML-R. Log of cumulative earnings (LCE; 0.19 ± 0.01), log of earnings per race start (0.23 ± 0.02) and best race distance (0.61 ± 0.03) were all significantly heritable. Fixed effects for sex were significant (P < 0.001) for all performance traits aside from LCE (P = 0.382). With the exception of annual earnings, trainer was also significant for all performance traits. As the application of modern genetic selection methodologies continues to gain popularity in the racing industry, contemporary heritability estimates from the current population of Thoroughbreds will play a vital role in identifying which traits are better suited to selection and in the development of more accurate genomic evaluations for racing performance.

Performance selection for Thoroughbreds racing in Hong Kong.

REASONS FOR PERFORMING STUDY: Different indicators of racing performance are commonly used in the racing industry to assess the genetic superiority of racing Thoroughbreds. However, how well these indicators predict the performance of future progeny or siblings varies depending on the population and circumstances in which the indicators were recorded or achieved. OBJECTIVES: To identify heritable indicators of racing performance for horses racing in Hong Kong. STUDY DESIGN: Heritability analysis of racing performance traits. METHODS: Performance data on the population of Thoroughbreds racing in Hong Kong between 3 September 2000 and 12 March 2011 (n = 4947) were acquired and used to estimate the heritabilities and probability values of fixed effects and covariates for a range of racing performance traits. Heritabilities for all performance traits were estimated using a single trait animal model. Each model included, as a minimum, the effects of sex, region of origin and trainer. RESULTS: Heritability estimates for traits relating to finish position ranged from 0.01 to 0.06. Average handicap weight had a heritability of 0.07 ± 0.03. The effects of sex (fixed) and trainer (random) were significant (P<0.05) for all performance traits relating to earnings measures, handicap weights and finish positions. The heritability of win time at 1600 m was 0.52 ± 0.06 and was the only significant estimate of heritability for win time in the current study. CONCLUSIONS: Although significantly affected by multiple environmental factors, certain indicators of Hong Kong racing performance can be reliably used to predict the performance of the individual's progeny or siblings. However, despite Hong Kong's controlled racing environment, these indicators appear to be no more heritable than in other less controlled racing environments.

Heritability of epistaxis in the Australian Thoroughbred racehorse population.

Post exercise epistaxis, the manifestation of a severe form of exercise-induced pulmonary haemorrhage (EIPH), has been observed in many equine racing populations. Although multiple analyses have suggested that non-genetic factors may lead to the development of this condition, relatively little consensus has been reached regarding its genetic aetiology. The objective of this study was to provide insight into both genetic and non-genetic factors that may contribute to the expression of epistaxis in the Australian Thoroughbred racing population. Racing records and reported epistaxis occurrences were acquired for 117,088 horses entered in races and official barrier trials from 1 August 2000 until 22 February 2011. Heritability was estimated using two different logistic generalised linear mixed models (lifetime epistaxis risk h(2) = 0.27 and individual race epistaxis risk h(2) = 0.50). Sex, age, and year of birth were shown to be significant; however, trainer, jockey, race distance, condition of the track (i.e. 'going'), racecourse, track surface, number of race starters, year and month of race were not significant. Evidence suggests genetic and non-genetic links to EIPH expressed as epistaxis.

Handedness of whip use by Australian Jockeys.

OBJECTIVE: To compare handedness of whip use by Australian jockeys in Melbourne (where racing is counterclockwise) and Sydney (where racing is clockwise). METHODS: Photographs of finishes of Thoroughbred horse races in Melbourne and Sydney were examined. Where whip use was clearly visible, the venue, the hand in which the whip was held and the names of the jockey and the horse were determined. Comparisons of whip hand use between cities were made using the Chi-squared test. RESULTS: A total of 771 identifications were made, 328 from Melbourne and 443 from Sydney, representing 78 jockeys and 506 horses. Right-handed whip use was identified in 244 (74.39%) photographs of Melbourne races and in 313 (70.65%) photographs of Sydney races. There was no difference between right-handed whip use in Melbourne and Sydney (P = 0.53), nor in the handedness of whip use by individual jockeys (P = 0.74). Predominantly right-handed jockeys demonstrated significantly stronger dominance (84.51 ± 14.03%) compared with left-hand dominant riders (71.07 ± 9.40%; P = 0.01). A total of 84 horses were identified being ridden by the same jockey in different races. In 64 of the 84 cases, the whip was used in the same hand in all photographs. In the remaining instances, the whip was observed to be used in both hands by the one jockey. CONCLUSION: The findings support the view the whip can be used as an aid to steering during races.