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Large‐scale ionospheric gradients associated with the solar terminator can deflect high frequency (HF) radio waves to off‐great circle paths during the morning and evening, negatively impacting technologies reliant on HF radio wave propagation. For example, geolocation algorithms used by scientific and military over‐the‐horizon radars (OTHRs) generally assume on‐great circle propagation, and thus lateral deviations from the great‐circle path can lead to positioning errors. In this study, radio wave propagation is simulated via 3D numerical ray traces though an empirical, high‐latitude model ionosphere initialized for a variety of times of the day and year to explore and quantify high‐latitude off‐great circle propagation associated with the solar terminator. Analysis of these simulations show large scale east‐west ionospheric gradients due to the solar terminator can cause lateral deviations in north‐directed propagation paths exceeding 20° at sunrise and sunset depending on radio wave frequency, though the largest portion of received signal power tends to experience maximum deflections of 5°. An exploration of the dependence of propagation direction on deflection shows that propagation paths parallel to the solar terminator tend to experience the largest deflections. Since the solar terminator at high latitudes is at an angle with respect to north in the winter and summer, propagation paths oriented west or east of north can experience larger deflections than north oriented paths at sunrise and sunset during these times of year. Impacts of these diurnal deflections on the operation of OTHR and scientific radar are discussed, as well as possible strategies for mitigating them. Plain Language Summary: High frequency (HF) radio waves are able to travel long distances by bouncing between the ionosphere (an upper layer of the Earth's atmosphere) and the ground. HF radio waves transmitted north can have their paths deflected east or west by changes in the ionosphere that happen at sunrise and sunset. In this paper, simulations of radio waves are used to explore how large these deflections can be and how they change over the course of the day and year. It is found that north pointing radio signals at certain frequencies can be deflected by more than 20° at sunrise and sunset. These simulations are also used to explore how radio waves transmitted in different directions are deflected at sunrise and sunset. It is found that radio waves transmitted along the dividing line between day and night tend to experience the largest deflections. The Earth is tilted with respect to its rotation, meaning this dividing line is not always aligned with North. The deviation from north is largest in the winter and summer. This means that radio waves transmitted west or east of north at these times of year can experience larger deflections than northward transmissions. Key Points: The lateral deflection of high frequency radio waves caused by the solar terminator is investigated with ray tracing simulationsNorth‐south propagation paths can experience significant (>20°) deflections in the morning and eveningEast‐west paths can also see significant deflections at high latitudes, at times when the solar terminator is also oriented east‐west [ABSTRACT FROM AUTHOR]

Aim: A course on sexual anamnesis based on peer teaching was developed, piloted, and evaluated at the medical school of the University of Würzburg. The course is part of the expansion of the communication curriculum and in order to close existing gaps in medical education. An implementation of the course in the curriculum is meant to give all students the opportunity to acquire professional skills in this area.Method: The course consists of knowledge transfer, interactive exercises, role plays with structured feedback, and an exchange with practitioners. A standardized online evaluation of the course took place in regard to teaching quality, subjective learning success, and acceptance. The voluntary course was conducted online in the summer semester of 2021 and in person in the winter semester of 2021/22. A total of 68 students participated. The training of the tutors was realized in cooperation with the “Deutsche Aidshilfe” (DAH).Results: The course was successfully conducted online and in person. A total of 60 students participated in the evaluation. More than 80% of the students rated the course as structured. They assessed an adequate mix of knowledge transfer and practical exercises. More than half of the students reported that they were more confident in performing sexual anamnesis after they participated in the course. There was an open exchange among the students. More than 90% of the students found the peer teaching by the tutors helpful.Conclusion: The implementation of the course closes a relevant gap of the curriculum in Würzburg. Sexual anamnesis will be a regular part of the curriculum starting in the winter semester 2022/23. The concept can also be transferred to other universities.

BackgroundIn 2013, the Organ Procurement and Transplantation Network began requiring transplant centers in the United States to collect and report postdonation living kidney donor follow-up data at 6 months, 1 year, and 2 years. Despite this requirement,

Patients with secondary pulmonary hypertension (SPH) often have both heart and lung disease, so combined heart-lung transplant (HLT) may be considered. Because SPH is rare, a nationwide study is necessary for sufficient power. This study evaluated survival after lung transplant (LT) vs HLT for SPH. Adult recipients of first-time LT or HLT for SPH in 2005-2021 were identified using the UNOS/OPTN database. Survival was compared for LT vs. HLT using Kaplan-Meier curves, log-rank test, and multivariable Cox regression adjusted for baseline recipient and donor characteristics with p<0.2 on univariate analysis. Of 255 recipients, there were 44 (17%) HLT and 211 (83%) LT. HLT and LT donor age, gender, and smoking history were similar. HLT and LT recipient gender, BMI, and race were similar, but HLT recipients were younger (46.5 vs. 61, p<0.001). HLT recipients were more likely to have ECMO usage (15.9% vs 1.9%, p<0.001) and prior cardiac surgery (65.9% vs 3.8%, p<0.001). HLT recipients had shorter ischemic time (3.7 vs 5.0 hrs, p<0.001). Post-transplant, HLT recipients had significantly worse outcomes compared to LT recipients, including longer length of stay (40 vs 20 days, p=0.003) and higher prevalence of stroke (9.1% vs 1.9%, p=0.04) and dialysis (36.4% vs 7.6%, p<0.001). Survival rates were similar between HLT and LT recipients in univariate analysis (Figure 1, log-rank p=0.09). HLT vs. LT recipient survival was 70.0% vs 82.5% at 1 year, 38.1% vs 70.0% at 3 years, and 31.4% vs 61.4% at 5 years. After adjusting for baseline donor and recipient characteristics, survival remained similar (aHR 1.28 (95% CI 0.64-2.54), p=0.49). For patients with SPH, HLT recipients had worse post-transplant complications but similar survival rates compared to LT recipients, suggesting that these patients may benefit from LT over HLT. [ABSTRACT FROM AUTHOR]

Lung-kidney transplantation (LKTx) is a therapeutic option for lung failure patients with concurrent renal dysfunction. A previous study reported 31 LKTx cases performed between 1995 and 2013 with a 1-year survival of 71%. Combined LKTx has since become more frequently performed. The objectives of this study were to: (1) evaluate outcomes following LKTx in the modern era and (2) compare the outcomes of combined LKTx and isolated lung transplantation (LTx) in recipients who had pre-existing renal failure. LKTx cases from 2011 to 2021 were retrospectively examined using registry data. Outcome comparisons were made with all isolated LTx cases as well as LTx cases involving recipients with pre-existing renal failure requiring dialysis. Primary outcomes included 30-day, 1-year, 3-year, and 5-year survival rates. Secondary outcomes included postoperative dialysis, acute lung and kidney allograft rejection, and hospital length of stay (LOS). Eighty-three LKTx cases were performed in the U.S. between 2011 and 2021. Combined LKTx cases had 30-day, 1-year, 3-year, and 5-year survival rates of 92.8%, 79.1%, 70.1%, and 63.5%, respectively. LKTx survival rates were comparable to survival following isolated LTx (1-year survival 87.9%; p=0.52), but combined LKTx demonstrated a survival advantage over isolated LTx in recipients with pre-existing renal failure (see Figure). LKTx recipients had a shorter LOS and a decreased need for post-transplant dialysis. Survival rates following LKTx have improved over the past decade and demonstrate a survival advantage over isolated LTx in recipients with pre-existing renal failure. Combined LKTx should be actively considered in LTx candidates who have underlying renal failure. [ABSTRACT FROM AUTHOR]

Physical frailty is a critical determinant of mortality in patients with cirrhosis and can be objectively measured using the Liver Frailty Index (LFI), which is potentially modifiable. We aimed to identify LFI cut-points associated with waitlist mortality. Ambulatory adults with cirrhosis without HCC awaiting liver transplantation from 9 centers from 2012 to 2021 for ≥3 months with ≥2 pre-liver transplantation LFI assessments were included. The primary explanatory variable was the change in LFI from first to second assessments per 3 months (∆LFI); we evaluated clinically relevant ∆LFI cut-points at 0.1, 0.2, 0.3, and 0.5. The primary outcome was waitlist mortality (death or delisting for being too sick), with transplant considered as a competing event. Among 1029 patients, the median (IQR) age was 58 (51-63) years; 42% were female; and the median lab Model for End-Stage Liver Disease-Sodium at first assessment was 18 (15-22). For each 0.1 improvement in ∆LFI, the risk of overall mortality decreased by 6% (cause-specific hazard ratio: 0.94, 95% CI: 0.92-0.97, p < 0.001). ∆LFI was associated with waitlist mortality at cut-points as low as 0.1 (cause-specific hazard ratio: 0.63, 95% CI: 0.46-0.87) and 0.2 (HR: 0.61, 95% CI: 0.42-0.87). An improvement in LFI per 3 months as small as 0.1 in the pre-liver transplantation period is associated with a clinically meaningful reduction in waitlist mortality. These data provide estimates of the reduction in mortality risk associated with improvements in LFI that can be used to assess the effectiveness of interventions targeting physical frailty in patients with cirrhosis., (Copyright © 2024 American Association for the Study of Liver Diseases.)

Background and Aims: Offering LT to frail patients may reduce waitlist mortality but may increase post-LT mortality. LT survival benefit is the concept of balancing these risks. We sought to quantify the net survival benefit with LT by liver frailty index (LFI)., Approach and Results: We analyzed data in the multicenter Functional Assessment in LT (FrAILT) study from 2012 to 2021. Pre-LT cohort included ambulatory patients with cirrhosis awaiting LT, without HCC; the post-LT cohort included those who underwent LT. Primary outcomes were pre-LT and post-LT mortality. We computed 1-, 3-, and 5-year restricted mean survival times (RMSTs) from adjusted Cox models. The survival benefit was calculated as a net gain in life-years with LT. Pre-LT cohort included 2628 patients: median Model for End-Stage Liver Disease-Sodium was 18 (IQR: 14-22); 731 (28%) were frail; 440 (17%) died before LT. Post-LT cohort included 1335 patients: median Model for End-Stage Liver Disease-Sodium was 20 (IQR: 14-24); 325 (24%) were frail; 103 (8%) died after LT. Pre-LT RMST decreased substantially as LFI increased. Post-LT RMST also decreased as LFI increased but only modestly. There was no LFI threshold at which pre-LT and post-LT RMST intersected-patients had net survival benefits at all LFI values., Conclusions: Pre-LT and, to a lesser degree, post-LT mortality increased as LFI increased. Transplant offered a survival benefit at all LFI values, driven by a reduction in pre-LT mortality. No threshold of LFI was identified at which the risk of post-LT mortality exceeded pre-LT mortality. LT offers net survival benefits even in the presence of advanced frailty among those selected for LT., (Copyright © 2024 American Association for the Study of Liver Diseases.)