Beyond scale-free networks: integrating multilayer social networks with molecular clusters in the local spread of COVID-19.

This study evaluates the scale-free network assumption commonly used in COVID-19 epidemiology, using empirical social network data from SARS-CoV-2 Delta variant molecular local clusters in Houston, Texas. We constructed genome-informed social networks from contact and co-residence data, tested them for scale-free power-law distributions that imply highly connected hubs, and compared them to alternative models (exponential, log-normal, power-law with exponential cutoff, and Weibull) that suggest more evenly distributed network connections. Although the power-law model failed the goodness of fit test, after incorporating social network ties, the power-law model was at least as good as, if not better than, the alternatives, implying the presence of both hub and non-hub mechanisms in local SARS-CoV-2 transmission. These findings enhance our understanding of the complex social interactions that drive SARS-CoV-2 transmission, thereby informing more effective public health interventions.

An updated evaluation of reported no-observed adverse effect levels for chrysotile, amosite, and crocidolite asbestos for lung cancer and mesothelioma.

This analysis updates two previous analyses that evaluated the exposure-response relationships for lung cancer and mesothelioma in chrysotile-exposed cohorts. We reviewed recently published studies, as well as updated information from previous studies. Based on the 16 studies considered for chrysotile (<10% amphibole), we identified the "no-observed adverse effect level" (NOAEL) for lung cancer and/or mesothelioma; it should be noted that smoking or previous or concurrent occupational exposure to amphiboles (if it existed) was not controlled for. NOAEL values ranged from 2.3-<11.5 f/cc-years to 1600-3200 f/cc-years for lung cancer and from 100-<400 f/cc-years to 800-1599 f/cc-years for mesothelioma. The range of best-estimate NOAELs was estimated to be 97-175 f/cc-years for lung cancer and 250-379 f/cc-years for mesothelioma. None of the six cohorts of cement or friction product manufacturing workers exhibited an increased risk at any exposure level, while all but one of the six studies of textile workers reported an increased risk at one or more exposure levels. This is likely because friction and cement workers were exposed to much shorter chrysotile fibers. Only eight cases of peritoneal mesothelioma were reported in all studies on predominantly chrysotile-exposed cohorts combined. This analysis also proposed best-estimate amosite and crocidolite NOAELs for mesothelioma derived by the application of relative potency estimates to the best-estimate chrysotile NOAELs for mesothelioma and validated by epidemiology studies with exposure-response information. The best-estimate amosite and crocidolite NOAELs for mesothelioma were 2-5 f/cc-years and 0.6-1 f/cc-years, respectively. The rate of peritoneal mesothelioma in amosite- and crocidolite-exposed cohorts was between approximately 70- to 100-fold and several-hundred-fold higher than in chrysotile-exposed cohorts, respectively. These findings will help characterize potential worker and consumer health risks associated with historical and current chrysotile, amosite, and crocidolite exposures.

Prehospital Intervention Improves Outcomes for Patients Presenting in Atrial Fibrillation with Rapid Ventricular Response.

OBJECTIVE: To compare outcomes of patients presenting to emergency medical services (EMS) with atrial fibrillation with rapid ventricular response (AF-RVR) who did and did not receive prehospital advanced life support (ALS) rate or rhythm control intervention(s). METHODS: This retrospective cohort study used the 2021 ESO Data Collaborative (Austin, TX) dataset. We identified 9-1-1 scene responses for patients aged 16 to 100 years old presenting with AF and an initial heart rate ≥ 110 beats per minute (bpm). Prehospital ALS interventions for AF-RVR included medications (e.g., calcium channel blockers, beta blockers, etc.) or electrical cardioversion. Outcome measures included prehospital rate control (i.e., final prehospital heart rate < 110 bpm), emergency department (ED) discharge to home, ED and hospital length of stay, and mortality. We also evaluated prehospital adverse events-specifically bradycardia, hypotension, and cardiac arrest. We used propensity score matching to compare outcomes among treated and untreated patients with similar demographic and clinical characteristics. We determined the average treatment effect on the treated (ATET) with 95% confidence intervals (CI) and the number needed to treat (NNT). RESULTS: After propensity score matching, prehospital outcomes were available for 4,859 treated patients matched with 4,859 similar untreated patients. Prehospital rate control was more frequent for treated than for untreated patients (41.0% vs. 18.2%, ATET +22.8%, CI: +21.1%; +24.6%, NNT = 5). Hospital outcomes were available for 1,347 treated patients matched with 1,347 similar untreated patients. Treated patients were more likely to be discharged from the ED (37.9% vs. 34.0%, ATET +3.9%, CI: +0.2%; +7.5%, NNT = 26) and less likely to die (4.3% vs. 6.7%, ATET -2.5%, CI: -4.2%; -0.8%, NNT = 40) compared to untreated patients. Hypotension occurred more often in treated patients (ATET +2.6%, CI: +1.5%; +3.7%), but resolved before ED arrival in 73% of affected patients. Otherwise, adverse event rates did not significantly differ for the two groups. CONCLUSIONS: In this propensity score matched study of patients presenting to EMS with AF-RVR, prehospital ALS interventions were associated with more frequent prehospital rate control, more frequent discharge to home from the ED, and lower mortality.

Occupational exposure to cosmetic talc and mesothelioma in barbers, hairdressers, and cosmetologists: A systematic review of the epidemiology.

Inhalation exposure to cosmetic talc has generated much scientific debate regarding its potential as a risk factor for mesothelioma, a rare, but fatal cancer. Barbers, hairdressers, and cosmetologists have regularly used cosmetic talc-containing products, but the collective epidemiological evidence for mesothelioma in these occupations has yet to be described. As such, we conducted a systematic review of PubMed and the National Institute for Occupational Safety and Health's (NIOSH) Numbered Publications list to identify original epidemiological literature reporting measures of association between these occupations and incidence of or death from mesothelioma. Literature screening was performed independently twice, the results of which were summarized and tabulated and underwent a review for their accuracy. A total of 12 studies met our inclusion criteria, including three cohort, six case-control, and three proportionate mortality/registration studies. The data from these studies were collected in 13 European and North American countries, spanning more than 50 years. We supplemented this review with queries of occupational mortality databases that are managed by the Washington State Department of Health and NIOSH for 26 U.S. states. Most findings were null and if statistically significant, nearly all showed an inverse relationship, indicative of a protective effect of these occupations on mesothelioma risk. Overall, the epidemiological evidence does not support an increased risk of mesothelioma for these occupations. This research fills an important data gap on the etiology of mesothelioma in barbers, hairdressers, and cosmetologists, and provides a benchmark for those with comparatively less exposure, such as non-occupational users of similar cosmetic talc-containing products.

Palliative Care Education in US Physical Medicine and Rehabilitation Residency Programs: Current Practices, Perceived Needs, and Barriers.

Background: Physical medicine and rehabilitation (PM&R) clinicians commonly care for patients with serious illness/injury and would benefit from primary palliative care (PC) training. Objective: To assess current practices, attitudes, and barriers toward PC education among U.S. PM&R residencies. Design: This is a cross-sectional study utilizing an electronic 23-question survey. Setting/Subjects: Subjects were program leaders from U.S. PM&R residency programs. Results: Twenty-one programs responded (23% response). Only 14 (67%) offered PC education through lectures, elective rotations, or self-directed reading. Pain management, communication, and nonpain symptom management were identified as the most important PC domains for residents. Nineteen respondents (91%) felt residents would benefit from more PC education, but only five (24%) reported undergoing curricular change. Lack of faculty availability/expertise and teaching time were the most endorsed barriers. Conclusion: PC education is heterogeneous across PM&R programs despite its perceived value. PC and PM&R educators can collaborate to build faculty expertise and integrate PC principles into existing curricula.

Group 13 salphen compounds (In, Ga and Al): a comparison of their structural features and activities as catalysts for cyclic carbonate synthesis.

Many complexes based on group 13 elements have been successfully applied as catalysts for the synthesis of cyclic carbonates from epoxides and CO2 and to date these have provided some of the most active catalysts developed. It is notable that most reports have focused on the use of aluminium-based compounds likely because of the well-established Lewis acidity of this element and its cost. In comparison, relatively little attention has been paid to the development of catalysts based on the heavier group 13 elements, despite their known Lewis acidic properties. This study describes the synthesis of aluminium, gallium and indium compounds supported by a readily prepared salphen ligand and explores both their comparative structures and also their potential as catalysts for the synthesis of cyclic carbonates. In addition, the halide ligand which forms a key part of the compound has been systematically varied and the effect of this change on the structure and catalytic activity is also discussed. It is demonstrated that the indium compounds are actually, and unexpectedly, the most active for cyclic carbonate synthesis, despite their lower Lewis acidity when compared to their aluminium congeners. The experimental observations from this work are fully supported by a Density Functional Theory (DFT) study, which provides important insights into the reasons as to why the indium catalyst with bromide, [InBr(salphen)], is most active.

Monitored and Modeled Ambient Air Concentrations of Ethylene Oxide: Contextualizing Health Risk for Potentially Exposed Populations in Georgia.

Recent studies have monitored and modeled long-term ambient air concentrations of ethylene oxide (EO) around emitting facilities in Georgia with the intent of informing risk management of potentially exposed nearby residential populations. Providing health context for these data is challenging because the U.S. Environmental Protection Agency's risk-specific concentrations lack practical utility in distinguishing a health significant increase in exposure. This study analyzes EO data for eight emitting facilities, using a previously published alternative exposure metric, the total equivalent concentration, which is based on U.S. Centers for Disease Control biomarker data for the non-smoking U.S. POPULATION: Mean concentrations for monitoring sites were compared to mean background concentrations to assess whether emissions contribute significantly to environmental concentrations. To assess the health significance of potential exposure at nearby residential locations, the 50th percentile concentration was added to the 50th percentile endogenous equivalent concentration and compared to the total equivalent concentration distribution for the non-smoking U.S. POPULATION: The findings demonstrate that impacts from nearby emission sources are small compared to mean background concentrations at nearby locations, and the total equivalent concentrations for exposed populations are generally indistinguishable from that of the 50th percentile for the non-smoking U.S.

Smooth and safe tram journeys: tram driver perspectives and opportunities using a haptic master controller in a virtual reality environment.

Tram drivers operate a master controller to control the acceleration and braking of the tram. Operation should ensure passenger comfort and safety through smooth tram motion and the avoidance of jerkiness that may cause passengers to fall in the carriage. This work investigates current driver practices and strategies for tram driving in normal operations through interviews and the capacity of a new haptic master controller to support drivers in achieving smooth and safe tram journeys. A haptic feedback algorithm based on viscosity was implemented on the master controller to provide drivers with feedback on the rate at which they were accelerating and braking the tram. This aspect was tested in a virtual tram within a simulated inner city virtual reality environment. Results indicate that the haptic master controller and coupled viscosity feedback algorithm did not increase smoothness of driving during the simulated experiences. Despite this, the drivers indicated a preference for the provision of further haptic information to support driving tasks and the overall journey safety and smoothness. Practitioner Summary: This research comprises two studies. The first investigates strategies currently used by drivers to operate a tram smoothly in order to elicit design requirements for a haptic tram master controller. The second study evaluates the impact of a novel haptic master controller on journey smoothness within a virtual environment.

Drastic Effect of Sequential Deposition Resulting from Flux Directionality on the Luminescence Efficiency of Nanowire Shells.

Core-shell nanowire heterostructures form the basis for many innovative devices. When compound nanowire shells are grown by directional deposition techniques, the azimuthal position of the sources for the different constituents in the growth reactor, substrate rotation, and nanowire self-shadowing inevitably lead to sequential deposition. Here, we uncover for In0.15Ga0.85As/GaAs shell quantum wells grown by molecular beam epitaxy a drastic impact of this sequentiality on the luminescence efficiency. The photoluminescence intensity of shell quantum wells grown with a flux sequence corresponding to migration enhanced epitaxy, that is, when As and the group-III metals essentially do not impinge at the same time, is more than 2 orders of magnitude higher than for shell quantum wells prepared with substantially overlapping fluxes. Transmission electron microscopy does not reveal any extended defects explaining this difference. Our analysis of photoluminescence transients shows that co-deposition has two detrimental microscopic effects. First, a higher density of electrically active point defects leads to internal electric fields reducing the electron-hole wave function overlap. Second, more point defects form that act as nonradiative recombination centers. Our study demonstrates that the source arrangement of the growth reactor, which is of mere technical relevance for planar structures, can have drastic consequences for the material properties of nanowire shells. We expect that this finding holds good also for other alloy nanowire shells.

Super-Resolution Photothermal Patterning in Conductive Polymers Enabled by Thermally Activated Solubility.

Doping-induced solubility control (DISC) patterning is a recently developed technique that uses the change in polymer solubility upon doping, along with an optical dedoping process, to achieve high-resolution optical patterning. DISC patterning can produce features smaller than predicted by the diffraction limit; however, no mechanism has been proposed to explain such high resolution. Here, we use diffraction to spatially modulate the light intensity and determine the dissolution rate, revealing a superlinear dependence on light intensity. This rate law is independent of wavelength, indicating that patterning resolution is not dominated by an optical dedoping reaction, as was previously proposed. Instead we show here that the optical patterning mechanism is primarily controlled by the thermal profile generated by the laser. To quantify this effect, the thermal profile and dissolution rate are modeled using a finite-element model and compared against patterned line cross sections as a function of wavelength, laser intensity, and dwell time. Our model reveals that although the laser-generated thermal profile is broadened considerably beyond the profile of the laser, the highly temperature dependent dissolution rate results in selective dissolution near the peak of the thermal profile. Therefore, the key factor in achieving super-resolution patterning is a strongly temperature dependent dissolution rate, a common feature of many polymers. In addition to suggesting several routes to improved resolution, our model also demonstrates that doping is not required for optical patterning of conjugated polymers, as was previously believed. Instead, we demonstrate that superlinear resolution optical patterning should be attainable in any conjugated polymer simply by tuning the solvent quality during patterning, thus extending the applicability of our method to a wide class of materials. We demonstrate the generality of photothermal patterning by writing sub-400 nm features into undoped PffBT4T-2OD.

Transition from elastic to plastic strain release in core-shell nanowires revealed by in-plane x-ray diffraction.

We investigate the strain evolution and relaxation process as function of increasing lattice mismatch between the GaAs core and surrounding In x Ga1-x As shell in core-shell nanowire heterostructures grown on Si(111) substrates. The dimensions of the core and shell are kept constant whereas the indium concentration inside the shell is varied. Measuring the [Formula: see text] and [Formula: see text] in-plane Bragg reflections normal to the nanowire side edges and side facets, we observe a transition from elastic to plastic strain release for a shell indium content x > 0.5. Above the onset of plastic strain relaxation, indium rich mounds and an indium poor coherent shell grow simultaneously around the GaAs core. Mound formation was observed for indium contents x = 0.5 and 0.6 by scanning electron microscopy. Considering both the measured radial reflections and the axial 111 Bragg reflection, the 3D strain variation was extracted separately for the core and the In x Ga1-x As shell.

Ethylene Oxide Exposure in U.S. Populations Residing Near Sterilization and Other Industrial Facilities: Context Based on Endogenous and Total Equivalent Concentration Exposures.

Given ubiquitous human exposure to ethylene oxide (EO), regardless of occupation or geography, the current risk-specific concentrations (RSCs: 0.0001-0.01 ppb) from the U.S. Environmental Protection Agency (EPA) cancer risk assessment for EO are not useful metrics for managing EO exposures to the general U.S. population. The magnitude of the RSCs for EO are so low, relative to typical endogenous equivalent metabolic concentrations (1.1-5.5 ppb) that contribute ~93% of total exposure, that the RSCs provide little utility in identifying excess environmental exposures that might increase cancer risk. EO monitoring data collected in the vicinity of eight EO-emitting facilities and corresponding background locations were used to characterize potential excess exogenous concentrations. Both 50th and 90th percentile exogenous exposure concentrations were combined with the 50th percentile endogenous exposure concentration for the nonsmoking population, and then compared to percentiles of total equivalent concentration for this population. No potential total exposure concentration for these local populations exceeded the normal total equivalent concentration 95th percentile, indicating that excess facility-related exposures are unlikely to require additional management to protect public health.

Airborne concentrations of chrysotile asbestos during operation of industrial crane controls and maintenance of associated arc chutes.

Some industrial crane control panels were historically equipped with chrysotile-containing arc chutes. Because of the paucity of data regarding potential exposure from such equipment, we used a simulation approach to quantify the release of chrysotile from arc chutes in two functional 1970s-era industrial crane control panels during operation and maintenance. Two experienced operators separately simulated operation of crane controls under load; one of these operators then simulated two arc chute maintenance protocols: sanding (protocol 1) and scraping, sanding, and blowing (protocol 2). The original arc chutes contained approximately 36% chrysotile. Personal breathing zone (PBZ) (n = 8) and area samples (n = 8) were collected and analyzed using phase contrast microscopy (PCM) and transmission electron microscopy. PCM-equivalent (PCME) concentrations were derived, from which 8-h time-weighted averages (TWA) were calculated. During operation, chrysotile was identified in one of the four PBZ samples, equivalent to a PCME concentration of 0.012 f/cm3 (8-h TWA: 0.011 f/cm3). During protocols 1 and 2, chrysotile was identified in all PBZ samples (n = 4); PCME concentrations (and corresponding 8-h TWA) were <0.013 and 0.021 f/cm3 (0.001 and 0.004 f/cm3) and 0.013 and 0.017 f/cm3 (0.003 f/cm3), respectively. Many of the airborne chrysotile fibers had matrix attached, supporting the low exposure potential during this work. These data indicate very low, if any, exposures to chrysotile asbestos during the simulated scenarios. In addition, these data could assist with refining assumptions in exposure reconstruction and inform the state-of-the science on low-level chrysotile exposure.

Demography of the Intertidal Fucoid Hormosira banksii: Importance of Recruitment to Local Abundance.

Canopy-forming macroalgae form the basis of diverse coastal ecosystems globally. The fucoid Hormosira banksii is often the dominant canopy-forming macroalga in the temperate intertidal of southern Australia and New Zealand, where it is commonly associated with an understory of coralline turf. Hormosira banksii is susceptible to both natural and anthropogenic disturbance and despite its abundance, few studies have examined the demography of this important species. This study determined the demographic response of H. banksii to different gradients of disturbance to both its canopy and to the understory coralline turf. We established plots in which the density of H. banksii and/or understory coralline turf was manipulated in a pulse perturbation to simulate a disturbance event. The manipulated plots contained eight treatments ranging from 100% removal of H. banksii to 100% removal of the understory coralline turf. We then measured recruitment and followed individual recruits for up to 18 months to determine growth and survivorship. We found that H. banksii recruitment was seasonally variable throughout the experiment and highest over summer, survivorship of recruits was generally high, and the species was slow-growing and long-lived. Moreover, the level of disturbance did not seem to affect recruitment, growth, or survivorship and post-recruitment mortality was independent of H. banksii density. In this system, it appears that H. banksii is a relatively long-lived perennial species whose demography is density-independent which appears to allow recovery from disturbance.

Hand-to-mouth and other hand-to-face touching behavior in a quasi-naturalistic study under controlled conditions.

Data gaps exist in our understanding of hand-to-mouth touching behavior among adults, despite its relevance for accurately characterizing inadvertent ingestion exposures to chemical and pathogenic microbial agents and consequent associated health risks. The present study describes detailed observations of the frequency and nature of hand-to-mouth and other hand-to-face touching behavior among 14 male and female volunteers in a controlled, quasi-naturalistic setting. Participants performed four 15-min tasks: 1) installation of a brass object as part of a short home improvement project, 2) completion of a pen-and-paper survey, 3) engagement in a telephone conversation, and 4) use of headphones to listen to music. Video recordings of the participants performing each task were reviewed and coded for touches to the face with emphasis on specific regions of the face and palmar versus dorsal contacts. During the installation task, only one of the 14 participants was observed touching his face; this was to the nose, on two separate occasions. Summed across the three non-installation tasks, including palmar and dorsal contacts, participants touched their lips, their mouth, and anywhere on their face on average (range) 5.1 (0-19), 0.4 (0-3), and 27.7 (6-49) times, respectively. Facial contacts during these three non-installation tasks were predominantly with the palmar surface of the hand. The implications of these data are contextually specific, as the potential health impacts of face touching behavior among adults might differ based upon toxicity or virulence of hand contaminants of interest.

X-ray diffraction reveals the amount of strain and homogeneity of extremely bent single nanowires.

Core-shell nanowires (NWs) with asymmetric shells allow for strain engineering of NW properties because of the bending resulting from the lattice mismatch between core and shell material. The bending of NWs can be readily observed by electron microscopy. Using X-ray diffraction analysis with a micro- and nano-focused beam, the bending radii found by the microscopic investigations are confirmed and the strain in the NW core is analyzed. For that purpose, a kinematical diffraction theory for highly bent crystals is developed. The homogeneity of the bending and strain is studied along the growth axis of the NWs, and it is found that the lower parts, i.e. close to the substrate/wire interface, are bent less than the parts further up. Extreme bending radii down to ∼3 µm resulting in strain variation of ∼2.5% in the NW core are found.

Association of personal exposure to power-frequency magnetic fields with pregnancy outcomes among women seeking fertility treatment in a longitudinal cohort study.

OBJECTIVE: To assess for the first time the potential relationships of personal exposure to magnetic fields (MF) with pregnancy outcomes among a cohort of women from a fertility clinic, addressing, through study design, some of the primary limitations of previous studies on this topic. DESIGN: Longitudinal preconception prospective cohort. SETTING: Fertility center. PATIENT(S): Our analysis included 119 women recruited from 2012 to 2018, who underwent in vitro fertilization (IVF) (n = 163 cycles) and/or intrauterine insemination (IUI) (n = 123 cycles). INTERVENTION(S): Women wore personal exposure monitors continuously for up to three consecutive 24-hour time periods separated by several weeks. MAIN OUTCOME MEASURE(S): Implantation, clinical pregnancy, live birth, and pregnancy loss. RESULT(S): The median and maximum of the overall daily mean (daily peak) MF exposure levels were 1.10 mG (2.14 mG) and 15.54 mG (58.73 mG), respectively. MF exposure metrics were highest among women who changed environments four or more times per day. Overall, no statistically significant associations between MF exposure metrics and fertility treatment or pregnancy outcomes were observed in crude or adjusted models. Effect estimates, both positive and negative, varied by outcome and the exposure metric, including the way in which exposure was modeled. CONCLUSION(S): Personal MF exposures were not associated with fertility treatment outcomes or pregnancy outcomes. Despite its limited size, strengths of the study include a longitudinal repeated-measures design, the collection of personal MF exposure data across multiple days, and carefully documented outcome and covariate information among a potentially susceptible study population.

Development of a novel method for estimating dermal contact with hand-applied cleaning solutions.

Quantitatively characterizing dermal exposure for workers and consumers performing tasks with hand-applied cleaning solution is complex as many of the assessment variables are scenario specific. One of the key variables necessary for quantitatively estimating dermal exposure is the surface area of the hand contacted by the cleaning solution. However, no relevant data or methods are available in the literature. This study evaluated the feasibility of a novel simulation approach to measure skin contact area specific to hand cleaning with various types of liquid cleaning products to refine exposure and risk estimates for users of these products. This approach incorporates cotton rags wetted with pigmented cleaning solutions, volunteers wearing white cotton gloves during hand cleaning with those cotton rags, and digital imaging of the pigmented solution-contacted gloves post-simulation to quantify area of the hand contacted by the cleaning solution. When applied across three separate cleaning solutions, a denatured alcohol, an aqueous solution, and a lacquer thinner, this novel method performed well in estimating both palmer and dorsal surface areas of the hand contacted during simulated cleaning. The volume of cleaning solution applied to the rag and thickness of the rag were consistent predictors of contacted surface area. For the denatured alcohol, the time spent cleaning was additionally correlated with contacted surface area. This study suggests that this novel simulation approach could be an important tool for reducing an important source of uncertainty in dermal exposure assessments involving hand-applied cleaning solutions.

Knee Ultrasonography to Determine Risk for Noncontact Injuries in Collegiate American Football Players.

Knee ultrasonography has been used effectively as a screening tool for determining risk for knee injuries in athletes. Ultrasonography may be a valuable screening tool for relative risk of noncontact knee injuries that occur over a typical playing career in collegiate American football players. In this prospective longitudinal study, we evaluated American football players (n = 48) in an academic institution affiliated with the National Collegiate Athletic Association Division I athletic program. Players underwent comprehensive ultrasonography of both knees prior to beginning their collegiate careers. Anatomic structures were evaluated for presence and severity of abnormalities. Noncontact lower extremity injuries sustained over the collegiate career of the subjects were documented. Data were analyzed for correlations, differences in proportions, and odds ratio (OR). Seventy-nine percent of the athletes had at least one ultrasonographic abnormality, with quadriceps tendon (47.9%) and patellar tendon (39.6%) abnormalities predominating. Seventy-nine percent of players had at least one noncontact lower extremity injury (23.5% involving the knee) during their careers with an average of 2.8 injuries per career. The majority of injuries occurred in the second and third playing years. There was a significantly higher likelihood of patellar tendon injury based on the presence of patellar tendon ultrasonographic pathology (p = 0.024; OR = 11x). There was a significantly higher likelihood of quadriceps muscle-tendon injury based on the presence of quadriceps tendon ultrasonography pathology (p = 0.0012; OR = 140x). All athletes sustaining meniscal injuries had preexisting joint effusion but no preexisting ultrasonographic meniscal pathology. Knee ultrasonography along with patient history and complete physical examination may help reduce injury risk through education, prevention, and training programs.