Structure and scaling of the middle ear in domestic dog breeds.

Although domestic dogs vary considerably in both body size and skull morphology, behavioural audiograms have previously been found to be similar in breeds as distinct as a Chihuahua and a St Bernard. In this study, we created micro-CT reconstructions of the middle ears and bony labyrinths from the skulls of 17 dog breeds, including both Chihuahua and St Bernard, plus a mongrel and a wolf. From these reconstructions, we measured middle ear cavity and ossicular volumes, eardrum and stapes footplate areas and bony labyrinth volumes. All of these ear structures scaled with skull size with negative allometry and generally correlated better with condylobasal length than with maximum or interaural skull widths. Larger dogs have larger ear structures in absolute terms: the volume of the St Bernard's middle ear cavity was 14 times that of the Chihuahua. The middle and inner ears are otherwise very similar in morphology, the ossicular structure being particularly well-conserved across breeds. The expectation that larger ear structures in larger dogs would translate into hearing ranges shifted towards lower frequencies is not consistent with the existing audiogram data. Assuming that the audiograms accurately reflect the hearing of the breeds in question, oversimplifications in existing models of middle ear function or limitations imposed by other parts of the auditory system may be responsible for this paradox.

Factors associated with urinary incontinence among Hispanic/Latina women in the United States: Findings from The Hispanic Community Health Study/Study of Latinos (HCHS/SOL).

PURPOSE: To identify factors associated with urinary incontinence (UI) in women of various Hispanic/Latina backgrounds. MATERIALS AND METHODS: We analyzed data from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), a multicenter, community-based cohort study which includes a health-related questionnaire assessing presence and type of UI. Complex survey logistic regression analysis was used to assess the cross-sectional association of Hispanic/Latina backgrounds and other factors of UI. All estimates accounted for HCHS/SOL survey design. RESULTS: Of 5027 women, 33.4% answered "yes" to UI. Rates of any UI ranged from approximately 21.9% to 40.3% in women of Dominican and Puerto-Rican background, respectively. Any UI and UI subtypes were associated with age older than 65 years, increasing body mass index, smoking status, any alcohol use, parity ≥3, and postmenopausal status. After controlling for covariates and when compared with women of Mexican background, women of Dominican background were less likely to have any UI (OR = 0.42, 95% CI 0.30-0.57), as were women of Cuban (OR = 0.48, 95% CI 0.37-0.62), Puerto-Rican (OR = 0.79, 95% CI 0.62-1.0), and mixed (OR = 0.62, 95% CI 0.39-0.99) background; and women of every other background except for South American were less likely to have stress UI. In addition, women of Cuban (OR = 0.53, 95% CI 0.32-0.86) and mixed (OR = 0.38, 95% CI 0.16-0.87) background were less likely to have urge UI than women of Mexican background. CONCLUSIONS: Our study demonstrates differences in UI by Hispanic/Latina background, suggesting collective designation of Hispanics/Latinas as a single ethnic group does not adequately describe UI among this diverse group.

Structure-function relationships in the nasal cavity of Arctic and subtropical seals.

The heating and moistening of inhaled air, and the cooling and moisture removal from exhaled air, are crucial for the survival of animals under severe environmental conditions. Arctic mammals have evolved specific adaptive mechanisms to retain warmth and water and restrict heat loss during breathing. Here, the role of the porous turbinates of the nasal cavities of Arctic and subtropical seals is studied with this in mind. Mass and energy balance equations are used to compute the time-dependent temperature and water vapor profiles along the nasal passage. A quasi-1D model based on computed tomography images of seal nasal cavities is used in numerical simulations. Measured cross-sectional areas of the air channel and the perimeters of the computed tomography slices along the nasal cavities of the two seal species are used. The model includes coupled heat and vapor transfer at the air-mucus interface and heat transfer at the interfaces between the tissues and blood vessels. The model, which assumes constant blood flow to the nose, can be used to predict the temperature of the exhaled air as a function of ambient temperature. The energy dissipation (entropy production) in the nasal passages was used to measure the relative importance of structural parameters for heat and water recovery. We found that an increase in perimeter led to significant decreases in the total energy dissipation. This is explained by improved conditions for heat and water transfer with a larger complexity of turbinates. Owing to differences in their nasal cavity morphology, the Arctic seal is expected to be advantaged in these respects relative to the subtropical seal.

Medical School Curricula and the Role of Third-Party Resources in Medical Student Urology Education.

OBJECTIVE: To assess the quality and extent of the urology education provided to medical students both by third-party resources (TPRs) and by the curriculum provided by medical schools METHODS: TPRs were assessed by systematically comparing the content of the 4 most common resources (Anking, Pathoma, Uworld, and First Aid) to the American Urological Association's Medical Student Curriculum (AUA-MSC). Medical school curricula were assessed via a survey sent to the top-150 allopathic medical schools in the United States. The survey asked about clinical and pre-clinical exposure to urology received by medical students at their school. RESULTS: The TPRs for Step 1 together covered 73.3% of the AUA-MSC topics, and for Step 2 covered 81.9%. First Aid covered 49.5% of Step 1 topics and 58.4% of Step 2 topics, Uworld covered 58.6% and 67.9%, respectively, and Anking covered 61.8% and 58.8%, respectively. Pathoma covered 28.1% of Step 1 topics. Survey results showed that 33/39 (84.6%) of schools have required urology coursework in preclinical years, but only 3/39 (7.7%) have required urology rotations in the third or fourth years. Of those without required rotations, 35/36 (97.2%) indicated that they offer an elective rotation in urology. CONCLUSION: There is little emphasis placed on urology after the preclinical years of medical school, pointing to a need for greater exposure to these topics regardless of the student's selected specialty. This need stems from incomplete knowledge provided by TPRs compared to the AUA-MSC. Drawing attention to this gap can provide insight for those creating future iterations of medical curricula and shed light on areas in need of improvement, which would ultimately benefit both patients and providers.

Comparison of Adult Female and Male PMHS Pelvis and Lumbar Response to Underbody Blast.

The goal of this study was to gather and compare kinematic response and injury data on both female and male whole-body Post-mortem Human Surrogates (PMHS) responses to Underbody Blast (UBB) loading. Midsized males (50th percentile, MM) have historically been most used in biomechanical testing and were the focus of the Warrior Injury Assessment Manikin (WIAMan) program, thus this population subgroup was selected to be the baseline for female comparison. Both small female (5th percentile, SF) and large female (75th percentile, LF) PMHS were included in the test series to attempt to discern whether differences between male and female responses were predominantly driven by sex or size. Eleven tests, using 20 whole-body PMHS, were conducted by the research team. Preparation of the rig and execution of the tests took place at the Aberdeen Proving Grounds (APG) in Aberdeen, MD. Two PMHS were used in each test. The Accelerative Loading Fixture (ALF) version 2, located at APG's Bear Point range was used for all male and female whole-body tests in this series. The ALF was an outdoor test rig that was driven by a buried explosive charge, to accelerate a platform holding two symmetrically mounted seats. The platform was designed as a large, rigid frame with a deformable center section that could be tuned to simulate the floor deformation of a vehicle during a UBB event. PMHS were restrained with a 5-point harness, common in military vehicle seats. Six-degree-of-freedom motion blocks were fixed to L3, the sacrum, and the left and right iliac wings. A three-degree-of freedom block was fixed to T12. Strain gages were placed on L4 and multiple locations on the pelvis. Accelerometers on the floor and seat of the ALF provided input data for each PMHS' feet and pelvis. Time histories and mean peak responses in z-axis acceleration were similar among the three PMHS groups in this body region. Injury outcomes were different and seemed to be influenced by both sex and size contributions. Small females incurred pelvis injuries in absence of lumbar injures. Midsized males had lumbar vertebral body fractures without pelvis injuries. And large females with injuries had both pelvis and lumbar VB fractures. This study provides evidence supporting the need for female biomechanical testing to generate female response and injury thresholds. Without the inclusion of female PMHS, the differences in the injury patterns between the small female and midsized male groups would not have been recognized. Standard scaling methods assume equivalent injury patterns between the experimental and scaled data. In this study, small female damage occurred in a different anatomical structure than for the midsized males. This is an important discovery for the development of anthropomorphic test devices, injury criteria, and injury mitigating technologies. The clear separation of small female damage results, in combination with seat speeds, suggest that the small female pelvis injury threshold in UBB events lies between 4 - 5 m/s seat speed. No inference can be made about the small female lumbar threshold, other than it is likely at higher speeds and/or over longer duration. Male lumbar spine damage occurred in both the higher- and lower lower-rate tests, indicating the injury threshold would be below the seat pulses tested in these experiments. Large females exhibited injury patterns that reflected both the small female and midsized male groups - with damaged PMHS having fractures in both pelvis and lumbar, and in both higher- and lower- rate tests. The difference in damage patterns between the sex and size groups should be considered in the development of injury mitigation strategies to protect across the full population.

Clinical variables associated with major adverse cardiac events following radical cystectomy.

Objectives: The objective of this study is to investigate the association between major adverse cardiac events (MACE) and clinical factors of patients undergoing radical cystectomy (RC) for bladder cancer. Materials and Methods: A retrospective analysis using the 2015-2020 National Surgical Quality Improvement Program database was performed on patients who underwent RC for bladder cancer. MACE was defined as any report of cerebrovascular accident, myocardial infarction, or thromboembolic events (pulmonary embolism or deep vein thrombosis). A multivariable-adjusted logistic regression was conducted to identify clinical predictors of postoperative MACE. Results: A total of 10 308 (84.2%) patients underwent RC with incontinent urinary diversion (iUD), and 1938 (15.8%) underwent RC with continent urinary diversion (cUD). A total of 629 (5.1%) patients recorded a MACE, and on the multivariable-adjusted logistic regression, it was shown that MACE was significantly associated with increased age (OR = 1.035, 95% CI: 1.024-1.046, p < 0.001), obesity (OR = 1.583, 95% CI: 1.266-1.978, p < 0.001), current smokers (OR = 1.386, 95% CI: 1.130-1.700, p = 0.002), congestive heart failure before surgery (OR = 1.991, 95% CI: 1.016-3.900; p = 0.045), hypertension (OR = 1.209, 95% CI: 1.016-1.453, p = 0.043), and increase the surgical time (per 10 min increase, OR = 1.010, 95% CI: 1.003-1.017, p = 0.009). We also report that increased age, obesity, and patients undergoing cUD (OR = 1.368, 95% CI: 1.040-1.798; p = 0.025) are associated with thromboembolic events. Conclusion: By considering the preoperative characteristics of patients, including age, obesity, smoking, congestive heart failure, and hypertension status, urologists may be able to decrease the incidence of MACE in patients undergoing RC. Urologists should aim for lower operative times as this was associated with a decreased risk of thromboembolic events.

Extreme Percutaneous Nephrolithotomy: A Case Series of Procedures Requiring Five or More Access Tracts.

Introduction: Percutaneous nephrolithotomy (PCNL) remains the gold standard treatment for patients with complete staghorn stones, for which multiple access tracts may be required. In this study, we describe a series of patients undergoing PCNL with a minimum of five dilated access tracts. Materials and Methods: We performed a multi-institutional retrospective review of 10 patients with complete staghorn stones who underwent PCNL requiring five or more access tracts. We recorded patient demographics, stone characteristics postoperative complications, and stone-free rates (SFRs). The primary endpoint was any postoperative complication. Secondary endpoints included SFR, operative time, and length of stay. SFR was defined as absence of stones or residual fragments <4 mm. Results: A total of 10 patients from two institutions were included. Access tract number ranged from 5 to 11, and median stone volume was 233,042 mm3. Seven patients (70%) experienced postoperative complications, ranging from Clavien II to IVa. Three patients (30%) required blood transfusions. Median operative time was 312 minutes ranging from 180 to 560 minutes. Five patients (50%) were stone-free after the initial procedure. Of those with residual fragments, 4 (40%) required reoperation to be rendered stone-free. Median length of stay was 2.5 days, with a range of 1-6 days. Conclusion: To our knowledge, this is the largest series of patients undergoing PCNL with five or more access tracts reported to date. This study confirms that PCNL with five or more tracts is feasible and relatively safe, albeit with a high rate of complications in the immediate postoperative period.