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Background: Hospice and palliative medicine is important in the education of pediatric residents. Little is known about if and how residents' learnings during a pediatric palliative care elective fulfill core competencies and Pediatrics subcompetencies as set forth by the Accreditation Council for Graduate Medical Education (ACGME) and published subspecialty competencies for residents in pediatric hospice and palliative medicine (pHPM). Objectives: To evaluate what residents are learning on a four-week pediatric palliative care elective rotation at a single institution and how these learnings fulfill ACGME and pHPM competencies. Setting/Subjects: Prompted, written reflections were collected from residents completing a pediatric palliative care rotation at a large, urban academic center in the United States between academic years 2016-2017 and 2020-2021. Measurements: A qualitative, inductive reasoning approach was used to analyze reflections for emergent themes and codes. A deductive approach was used to map resulting codes to ACGME core competencies, Pediatric subcompetencies, and pHPM competencies. Results: Twenty-five resident reflections were collected. Inductive analysis revealed three primary themes and 102 codes. These codes were mapped to all six ACGME core competencies and mapped to most Pediatric subcompetencies with the exception of performing a physical examination, organizing and prioritizing patients, diagnostic evaluation, and community and population health. Codes mapped to most pHPM competencies with the exception of two symptom-based competencies, malignant bowel obstruction and severe fatigue. Conclusions: Residents' written reflections following a pediatric palliative care elective rotation demonstrated robust learnings that fulfill many core, specialty, and subspecialty competencies, particularly those that relate to patient- and family-centered care, communication, professionalism, and systems-based practice.

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Dichloroacetate (DCA), an inhibitor of pyruvate dehydrogenase kinase (PDK), regulates substrate metabolism in the heart. AMP-activated protein kinase (AMPK) is an age-related energy sensor that protects the heart from ischemic injury. This study aims to investigate whether DCA can protect the heart from ischemic injury through the AMPK signaling pathway. Young (3-4 months) and aged (20-24 months) male C57BL/6J mice were subjected to ligation of the left anterior descending coronary artery (LAD) for an in vivo ischemic model. The systolic function of the hearts was significantly decreased in both young and aged mice after 45 min of ischemia and 24 h of reperfusion. DCA treatment significantly improved cardiac function in both young and aged mice. The myocardial infarction analysis demonstrated that DCA treatment significantly reduced the infarction size caused by ischemia/reperfusion (I/R) in both young and aged mice. The isolated-cardiomyocyte experiments showed that DCA treatment ameliorated contractile dysfunction and improved the intracellular calcium signal of cardiomyocytes under hypoxia/reoxygenation (H/R) conditions. These cardioprotective functions of DCA can be attenuated by inhibiting AMPK activation. Furthermore, the metabolic measurements with an ex vivo working heart system demonstrated that the effects of DCA treatment on modulating the metabolic shift response to ischemia and reperfusion stress can be attenuated by inhibiting AMPK activity. The immunoblotting results showed that DCA treatment triggered cardiac AMPK signaling pathway by increasing the phosphorylation of AMPK's upstream kinase liver kinase B1 (LKB1) under both sham operations and I/R conditions. Thus, except from modulating metabolism in hearts, the cardioprotective function of DCA during I/R was mediated by the LKB1-AMPK pathway.

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In this paper we report, for the first time, the alignment enhanced photoconductivity of single wall carbon nanotube films upon laser illumination. The photoconductivity exhibited an increase, decrease or even 'negative' values when the laser spot was on different positions between contact electrodes, showing a 'position' dependent photoconductivity of partially aligned films of carbon nanotubes. Photon induced charge carrier generation in single wall carbon nanotubes and subsequent charge separation across the metal-carbon nanotube contacts is believed to cause the photoconductivity changes. A net photovoltage of approximately 4 mV and a photocurrent of approximately 10 microA were produced under the laser intensity of approximately 273 mW with a quantum efficiency of approximately 7.8% in vacuum. The photocurrent was observed to be in the direction of nanotube alignment. Finally, there was a strong dependence of the polarization of the incident light on the photocurrent and the orientation of the films influenced the dynamics of the rise and fall of the photocurrent. All of these phenomena clearly have significance in the area of design and fabrication of solar cells, micro-opto-mechanical systems and photodetectors based on carbon nanotubes.

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We report the sonochemical synthesis of platinum nanowires on carbon nanotube templates and their application in electrochemical actuation. The fabrication of platinum nanowires was achieved by suspending well separated single wall carbon nanotubes in isopropyl alcohol and ultra-sonically agitating the solution in the presence of dihydrogen hexachloroplatinate. The platinum nanowires were further processed into micro and macro scale free standing sheets by vacuum filtration. An electrochemical cantilever actuator was constructed using the platinum nanowire sheet which actuated under electrical bias. Displacement of '3 mm was readily achieved when the electrical potential was swept at low voltages between -2 V and 2 V at a scan rate of 200 mV/s. The actuator showed the metallic actuation characteristics instead of that from carbon nanotubes. These results show the applicability of metallic nanomaterials for actuation technologies.

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