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The hydrazone functional group, when coupled with a pyridyl substituent, offers a unique class of widely tunable photoswitches, whose E-to-Z photoisomerization equilibria can be controlled through intramolecular hydrogen bonding between the N–H hydrazone donor and the pyridyl acceptor. However, little is known about the photoisomerization mechanism in this class of compounds. To address this issue, we report a pyridine-appended iminoguanidinium photoswitch that is functionally related to acylhydrazones and provides insight into the photoisomerization processes between the E and Z configurations. The E-to-Z photoisomerization of the E-2-pyridyl-iminoguanidinium cation (2PyMIG) in DMSO, prepared as the bromide salt, was quantified by ¹H NMR, and probed in real time with ultrafast laser spectroscopy. The photoisomerization process occurs on a picosecond timescale, resulting in low fluorescence yields. The multiconfigurational reaction path found with the growing string method features a small barrier (4.3 or 6.5 kcal mol−1) that the E isomer in the π–π* state must overcome to reach the minimum energy conical intersection (MECI) connecting the E and Z isomers of 2PyMIG. While two possible pathways exist depending on the orientation of the pyridine ring, both exhibit the same qualitative features along the path and at their MECIs, involving simultaneous changes in the CCNN and CNNC dihedral angles. Furthermore, the ground state barrier for pyridine ring rotation is readily accessible, thus a low barrier pathway to the experimentally observed Z isomer exists for both MECIs leading to a transition from the E isomer to photoproduct. Combining multiconfigurational reaction path calculations using growing string method with time-resolved fluorescence spectroscopy provided crucial insights into the photoisomerization process of 2PyMIG, resulting in both the computational and experimental results pointing to rapid photoisomerization via a surface crossing between the singlet π–π* and the ground states. [ABSTRACT FROM AUTHOR]

The vertical merger of AT&T and Time Warner combined one of the largest multiple video program distributors (MVPDs) in the United States with one of the largest providers of pay-TV programming. This study evaluates the potential competitive effects of the transaction by considering changes in the equity valuations of the respective upstream and downstream competitors to the merging parties when news of their proposed merger became public. Consistent with the government's central theory of harm, it appears that financial markets expected the proposed transaction to result in Time Warner increasing its carriage fees to AT&T's and DirecTV's MVPD rivals. Market reactions to the announcement of AT&T's commitment to enter into binding arbitration when negotiating future carriage fees for Tuner content provide further support for this inference. The results are difficult to rationalize in terms of the various efficiencies and synergies that AT&T claimed it would realize from the merger. [ABSTRACT FROM AUTHOR]

1. Participants will be able to summarize the key components of the four-week curriculum offer to 4th year medical students. 2. Participants will be able to evaluate the efficacy of the curriculum based on the learner-reported feedback about the educational curriculum. This presentation summarizes the evaluations of 81 medical students who participated in an immersive palliative care elective during the past six years. Our findings show increases in learner self-perception of preparedness to lead serious illness conversations and care for symptomatic patients at end-of-life. Student feedback highlights repeated calls for increased exposure to palliative care in the medical school curriculum. There is an urgent need to equip all medical providers with primary palliative care skills to meet the needs of patients with serious illness, particularly given the aging population of the United States. One way to address this need is to offer more palliative care training to medical students. We designed and evaluated an immersive, four-week elective for fourth year medical students as a potential model for enhancing primary palliative care skills. This elective was offered to two fourth-year medical students per month. Students spend two weeks on the adult palliative care consult service, one week at our inpatient hospice unit, and one week with either pediatric palliative care, radiation oncology, anesthesia pain, or additional time on the adult palliative care consult service. During the elective, students spend time with each member of the interdisciplinary team. Each student also leads an end-of-rotation presentation on a topic of their choosing and completes a reflection that allows them to process their experiences. To evaluate the curriculum, each student completes a pre-survey and post-survey. From 2017-2023, 81 students participated in the elective. All students completed the pre-survey and 85% completed the post-survey. Self-reported preparedness for serious illness communication increased from 38% to 100%. Comfort in leading code status discussions increased from 58% up to 100%. Learners unanimously reported that they felt better prepared to handle end-of-life issues and manage symptoms in seriously ill patients. In the qualitative analysis, students confirmed that their goals for the elective were met. Student feedback was critical of the lack of palliative care education throughout the standard medical school curriculum and called for earlier exposure. The feedback about this elective was overwhelmingly positive with students reporting significant improvement in self-perceived palliative care skills. Many called for more palliative care education earlier in medical school. Workforce / Career Development [ABSTRACT FROM AUTHOR]

1. Upon completion of this session, participants will be able to describe the ethical challenges in decision-making for patients with life-threatening though potentially survivable injury after attempted suicide. 2. Upon completion of this session, participants will be able to analyze methods for resolving clinical and ethical conflicts related to end-of-life decision making for patients with serious mental illness. Medical decision-making for patients without decision-making capacity who have attempted suicide can present ethical challenges, particularly when a patient has a life-threatening though potentially survivable injury. We present a modified case that highlights the need for interdisciplinary guidelines and best-practices for the care of these patients. Mr. C is a 56-year-old man with history of schizoaffective disorder complicated by previous suicide attempts. He presented to the hospital following a self-inflicted gunshot wound to the head. He was intubated in the field and was found to have significant intracranial bleeding and facial disfigurement. By legal default, his younger brother was his surrogate decision-maker. After emergency stabilization, providers shared that Mr. C had an estimated 50% chance of survival if he were to proceed with a high-risk series of intracranial evacuation and reconstructive plastics procedures, followed by months of high-intensity rehabilitation. Comfort-focused care and compassionate extubation were proposed as the alternative treatment plan. The palliative care, ethics, legal, and psychiatry teams were consulted, with trauma surgery and neurosurgery co-managing. Mr. C's brother desired to transition to comfort-focused care based on his mental health history and prior conversations about goals/values. However, the psychiatry team felt a "legal and ethical obligation" existed to proceed with full treatment given the potential for survival. They felt Mr. C's diagnosis of schizoaffective disorder was not treatment refractory and raised concerns that caregiver burnout may be affecting the brother's decision-making. The surgical teams also supported proceeding with treatment. After further discussion, the hospital legal and ethics teams deemed that Mr. C's brother was acting as an appropriate surrogate. As such, Mr. C was transferred to inpatient hospice, compassionately extubated, and died with his brother at his side. Mr. C's case highlights the challenges of medical decision-making for patients with suicide attempts and life-threatening though potentially survivable injuries. These cases can lead to significant moral distress for medical providers and families. We propose a standard of care that balances surrogate decision-maker experience and knowledge of prior goals of care as well as quality of life considerations with available treatment and prognostic information. Ethical / Legal Aspects of Care; Interdisciplinary Teamwork / Professionalism [ABSTRACT FROM AUTHOR]

1. Evaluate current resident education models for teaching Hospice and Palliative Medicine topics and identify education gaps. 2. Adapt more effective methods for integrating Hospice and Palliative Medicine topics into current resident education models. This poster centers around assessing identified gaps in hospice and palliative medicine education topics among internal medicine, family medicine and med-peds residents at a large academic medical center, creating a series of five educational sessions based on needs assessment data, and measuring pre-and post-education session confidence levels. The United States currently lacks enough palliative care (PC) physicians to meet the palliative care needs for all seriously ill patients. One way to address this need is to provide primary PC education to all resident physicians. The University of North Carolina (UNC) Internal Medicine (IM), Family Medicine (FM), and Med-Peds residencies currently lack a comprehensive Hospice and Palliative Medicine (HPM) curriculum. A recent needs assessment of UNC residents in the above specialties identified gaps in pain management and prognostic communication. Five high yield topics were identified based on review of the literature1,2 and our internal needs assessment: Non-pain Symptom Management, Basics of Hospice, How to Discuss Prognosis, Communicating about Life Sustaining Measures, and Pain Management. Five expert clinicians were selected to deliver lectures, and a curriculum planning sheet was distributed. Pre and post-lecture surveys were distributed to assess resident characteristics, baseline confidence, and post-lecture confidence in the selected topics using a 5-point Likert scale of 1 being not very confident and 5 being extremely confident. 52 pre and post survey sets were collected during the didactics series. There was a statistically significant increase in self-reported confidence in lecture objectives for the non-pain symptom management, pain management, and basics of hospice topics. Increases in self-reported confidence for the lectures on prognosis and communication about life sustaining measures were not statistically significant. Our needs assessment and lecture series improved resident confidence in key HPM topics and provides an excellent foundation for further HPM education throughout UNC and beyond. Workforce / Career DevelopmentQuality Improvement [ABSTRACT FROM AUTHOR]

The hydrazone functional group, when coupled with a pyridyl substituent, offers a unique class of widely tunable photoswitches, whose E -to- Z photoisomerization equilibria can be controlled through intramolecular hydrogen bonding between the N-H hydrazone donor and the pyridyl acceptor. However, little is known about the photoisomerization mechanism in this class of compounds. To address this issue, we report a pyridine-appended iminoguanidinium photoswitch that is functionally related to acylhydrazones and provides insight into the photoisomerization processes between the E and Z configurations. The E -to- Z photoisomerization of the E -2-pyridyl-iminoguanidinium cation (2PyMIG) in DMSO, prepared as the bromide salt, was quantified by 1 H NMR, and probed in real time with ultrafast laser spectroscopy. The photoisomerization process occurs on a picosecond timescale, resulting in low fluorescence yields. The multiconfigurational reaction path found with the growing string method features a small barrier (4.3 or 6.5 kcal mol -1 ) that the E isomer in the π - π * state must overcome to reach the minimum energy conical intersection (MECI) connecting the E and Z isomers of 2PyMIG. While two possible pathways exist depending on the orientation of the pyridine ring, both exhibit the same qualitative features along the path and at their MECIs, involving simultaneous changes in the CCNN and CNNC dihedral angles. Furthermore, the ground state barrier for pyridine ring rotation is readily accessible, thus a low barrier pathway to the experimentally observed Z isomer exists for both MECIs leading to a transition from the E isomer to photoproduct. Combining multiconfigurational reaction path calculations using growing string method with time-resolved fluorescence spectroscopy provided crucial insights into the photoisomerization process of 2PyMIG, resulting in both the computational and experimental results pointing to rapid photoisomerization via a surface crossing between the singlet π - π * and the ground states.

This manuscript describes the development of alkyne addition to the aziridine moiety of aziridinoquinoxalines using dual Ir(III)/Cu(I) catalytic system under green light-emitting diode (LED) photolysis (λ max =525 nm). This mild method features high levels of chemo- and regioselectivity and was used to generate 30 highly functionalized substituted dihydroquinoxalines in 36-98 % yield. This transformation was also carried asymmetrically using phthalazinamine-based chiral ligand to provide 9 chiral addition products in 96 : 4 to 86 : 14 e.r. The experimental and quantum chemical explorations of this reaction suggest a mechanism that involves Ir(III)-catalyzed triplet energy transfer followed by a ring-opening reaction ultimately leading to the formation of azomethine ylide intermediates. These azomethine intermediates undergo sequential protonation/copper(I) acetylide addition to provide the products., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)