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Serratia marcescens is a gram-negative bacillus that is an opportunistic agent in respiratory tract infections, urinary tract infections, and septicemia. It is rarely a cause of infective endocarditis, but in cases of endocarditis, it follows a rapid and devastating course.A previously healthy female in her mid-50s presented with fever, abdominal pain, right lower extremity pain, and diarrhea. Blood cultures were positive for S. marcescens, and additional evaluation revealed infarction in the spleen and kidneys, raising concern for endocarditis with associated embolic phenomena. The patient was subsequently found to have an embolus in the right popliteal artery and underwent a right popliteal thromboembolectomy. Antimicrobial therapy with cefepime and gentamicin was begun. A transesophageal echocardiogram revealed a large, mobile mitral valve vegetation. Care was complicated by intracranial hemorrhage, and the decision was made to withdraw care.A review of the databases Embase and PubMed revealed 63 additional cases of S. marcescens endocarditis. Analysis of these cases demonstrated a preponderance of aortic and mitral valve involvement, not tricuspid valve involvement, despite a risk factor of intravenous drug use in over 60% of cases. Mortality was 50%, and sequelae such as congestive heart failure and renal insufficiency occurred in the majority of survivors. In conclusion, S. marcescens is a rare but devastating cause of endocarditis with a primary risk factor of intravenous drug use but with a predilection for left-sided valvular lesions, not right-sided lesions.

This study investigates the feasibility of using a heavy-lift variant of the Lunar Surface Manipulator System (LSMS-H) to lift and handle a 12 metric ton payload. Design challenges and requirements particular to handling heavy cargo were examined. Differences between the previously developed first-generation LSMS and the heavy-lift version are highlighted. An in-depth evaluation of the tip-over risk during LSMS-H operations has been conducted using the Synergistic Engineering Environment and potential methods to mitigate that risk are identified.The study investigated three specific offloading scenarios pertinent to current Lunar Campaign studies. The first involved offloading a large element, such as a habitat or logistics module, onto a mobility chassis with a lander-mounted LSMS-H and offloading that payload from the chassis onto the lunar surface with a surface-mounted LSMS-H. The second scenario involved offloading small pressurized rovers with a landermounted LSMS-H. The third scenario involved offloading cargo from a third-party lander, such as the proposed ESA cargo lander, with a chassis-mounted LSMS-H. In all cases, the analyses show that the LSMS-H can perform the required operations safely. However, Chariot-mounted operations require the addition of stabilizing outriggers, and when operating from the Lunar surface, LSMS-H functionality is enhanced by adding a simple ground anchoring system. Nomenclature = slew ½ angle = guy angle relative to the horizontal βR = LSMS length from shoulder to elbow = horizontal distance from the tipping fulcrum to the insipient tip over limit using chassis mount dd critical = horizontal distance from the tipping fulcrum to the CG of down-slope payloads du critical = horizontal distance from the tipping fulcrum to the CG of up-slope payloads F a, F c = reaction forces on the left or right of the tipping fulcrum F guy = force in the guy wire F groundanchor = force in the ground anchor g l = lunar gravity h cg = CG height h gm = ground mount height LSMS = Lunar Surface Manipulator System LSMS-H = Heavy-lift Lunar Surface Manipulator System LSS = Lunar Surface Systems l chariot = chassis length lp lsms = distance between LSMS and chassis when chassis-mounted M (element) = element mass m i , m j = mass of elements to left and right of tipping fulcrum R = maximum LSMS reach = LSMS shoulder height to reach ratio θ 1 = LSMS kingpost rotation angle θ 2 = LSMS shoulder rotation angle θ 3 = LSMS elbow rotation angle

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INTRODUCTION Traditionally applied airway anatomy landmarks are not taught separately but assumed as part of pharynx (nasal, oral, larynx) teaching to first year healthcare students. Often minimal airway dissection is conducted to cadavers unless sagittal plane anatomy is achieved. Acquiring proper airway skills is necessary for all providers as it saves lives, however, it is notoriously difficult due to multifactorial parameters of structure orientation, angles, tissue compliance and age variation. Current simulation is unrealistic (except 7‐Sigma) regarding kinesthetic sense of soft tissue and demonstrating recognized landmarks with accurate orientation. Hospitals provide simulation opportunities for airway skills practice but rarely include mixed wet and dry simulation. Objective of this study was to integrate sagittal cadaver dissection with the most current medical technologies revealing actual 3D human airway anatomy while acquiring clinical intubation, bronchoscopy and ultrasound skills with first year medical and physician assistant students. METHODS Literature search was conducted to identify multimodal approach to teaching clinical airway anatomy and skills during first year undergraduate medical training. Anatomy texts and atlases were assessed to confirm if recognized clinical airway anatomy landmarks were described separately as a group and/or illustrated as such. Anatomy skills lab included embalmed cadavers for head and neck dissection in the sagittal plane with subsequent sternum and anterior rib cage removal. Airway technology stations with short tutorials included Sectra 3D interactive imaging table, 7‐Sigma airway intubation simulator with lifelike kinesthetic sense, Eagle Vision video laryngoscope, Glidescope Bflex bronchoscopy and Sonivate ultrasound finger probe were set up chronologically to develop applied anatomy and clinical skills. SUMMARY Literature search revealed no known studies with current multiple airway technologies taught and experienced sequentially in a single setting by first year students during anatomy. No commonly used texts or atlases described/demonstrated specific grouped airway anatomy landmarks to enable airway technology navigation and use. Students enthusiastically embraced the short tutorials and medical technology while rotating chronologically between stations. They subsequently facilitated individual stations (experience one‐teach one). CONCLUSION Airway anatomy for intubation, bronchoscoping and ultrasound skills are somewhat of an enigma, as logically it appears simple but in reality is relatively complex and challenging even for experienced providers. This study revealed recognized clinical anatomy airway landmarks are not highlighted or grouped together in common texts/atlases to better enable a learner to orientate themselves while using airway technology to perform tasks. Future studies are assessing students recognition of airway anatomy landmarks and efficient use of current airway technology. Support or Funding Information None to disclose.