2,497 research outputs found
Molybdenum oxide MoOₓ: a versatile hole contact for silicon solar cells
This letter examines the application of transparent MoOₓ (x < 3) films deposited by thermal evaporation directly onto crystalline silicon (c-Si) to create hole-conducting contacts for silicon solar cells. The carrier-selectivity of MoOₓ based contacts on both n- and p-type surfaces is evaluated via simultaneous consideration of the contact recombination parameter J oc and the contact resistivity ρ c. Contacts made to p-type wafers and p⁺ diffused regions achieve optimum ρ c values of 1 and 0.2 mΩ·cm², respectively, and both result in a Joc of ∼200 fA/cm². These values suggest that significant gains can be made over conventional hole contacts to p-type material. Similar MoOₓ contacts made to n-type silicon result in higher Joc and ρc with optimum values of ∼300 fA/cm² and 30 mΩ·cm² but still offer significant advantages over conventional approaches in terms of contact passivation, optical properties, and device fabrication.This project was partially
funded by The Australian Renewable Energy Agency
Effect of boron concentration on recombination at the p-Si–Al2O3 interface
We examine the surface passivation properties of Al₂O₃ deposited on boron-doped planar crystalline silicon surfaces as a function of the boron concentration. Both uniformly doped and diffused surfaces are studied, with surface boron concentrations ranging from 9.2 × 10¹⁵ to 5.2 × 10¹⁹ cm⁻³. Atmospheric pressure chemical vapor deposition and thermal atomic layer deposition are used to deposit the Al₂O₃ films. The surface recombination rate of each sample is determined from photoconductance measurements together with the measured dopant profiles via numerical simulation, using the latest physical models. These values are compared with calculations based on the interface properties determined from capacitance–voltage and conductance measurements. It is found that the fundamental surface recombination velocity of electrons, Sn 0 , which describes the chemical passivation of the interface, is independent of the surface boron concentration Ns for Ns ≤ 3 × 10¹⁹ cm⁻³, and in excellent agreement with values calculated from the interface state density Dit and capture coefficients cn and cp measured on undiffused boron-doped surfaces. We conclude that the physical properties of the Si– Al₂O₃ interface are independent of the boron dopant concentration over this range
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Antagonizing CD105 enhances radiation sensitivity in prostate cancer.
Radiation therapy is the primary intervention for nearly half of the patients with localized advanced prostate cancer and standard of care for recurrent disease following surgery. The development of radiation-resistant disease is an obstacle for nearly 30-50% of patients undergoing radiotherapy. A better understanding of mechanisms that lead to radiation resistance could aid in the development of sensitizing agents to improve outcome. Here we identified a radiation-resistance pathway mediated by CD105, downstream of BMP and TGF-β signaling. Antagonizing CD105-dependent BMP signaling with a partially humanized monoclonal antibody, TRC105, resulted in a significant reduction in clonogenicity when combined with irradiation. In trying to better understand the mechanism for the radio-sensitization, we found that radiation-induced CD105/BMP signaling was sufficient and necessary for the upregulation of sirtuin 1 (SIRT1) in contributing to p53 stabilization and PGC-1α activation. Combining TRC105 with irradiation delayed DNA damage repair compared to irradiation alone. However, in the absence of p53 function, combining TRC105 and radiation resulted in no reduction in clonogenicity compared to radiation alone, despite similar reduction of DNA damage repair observed in p53-intact cells. This suggested DNA damage repair was not the sole determinant of CD105 radio-resistance. As cancer cells undergo an energy deficit following irradiation, due to the demands of DNA and organelle repair, we examined SIRT1's role on p53 and PGC-1α with respect to glycolysis and mitochondrial biogenesis, respectively. Consequently, blocking the CD105-SIRT1 axis was found to deplete the ATP stores of irradiated cells and cause G2 cell cycle arrest. Xenograft models supported these findings that combining TRC105 with irradiation significantly reduces tumor size over irradiation alone (p value = 10-9). We identified a novel synthetic lethality strategy of combining radiation and CD105 targeting to address the DNA repair and metabolic addiction induced by irradiation in p53-functional prostate cancers
Low resistance Ohmic contact to p-type crystalline silicon via nitrogen-doped copper oxide films
Let the Patient Discharge Follow-Up Call Data Do the Talking!
Abstract Category: Practice Innovation / Performance Improvement (PI)
Purpose: The purpose of this initiative was to review the Patient Discharge Follow-Up Call (PDFC) Data, point out its importance and identify the issues presented in order to bring awareness to key stakeholders and continue to monitor the impact on patient outcomes.
Methods: In mid-February of 2018, based on the collected PDFC Data, the PI Director, PI Coordinator, Statistician and Quality Assurance Nurse (QAN) identified opportunities to educate Nursing, Hospitalists, Pharmacy, and Leadership on the issues related to discharge medications potentially leading to a return visit to the Emergency Department (ED), possible readmission and adverse patient outcomes. In early March of 2018, this team presented information for awareness purposes, gathered an Interdisciplinary team to review data and worked on opportunities.
Findings: All patients discharged from West Kendall Baptist Hospital (WKBH) receive a follow-up phone call from the QAN within 24-48 hours. Out of the 3,897 PDFC in the period of September 2017-February 2018 approximately 70% of patients were reached. Of those patients that reported issues (2.7%), the majority (63%) reported issues related to discharge medications.
Discussion: In as much as the majority of the patients reported no issues, the small percentage who had problems with medications related to prescribing warranted an intervention to prevent possible readmissions and reduce adverse patient outcomes. The team decided to address the medication issues by implementing the following:
Address verification of accuracy of preferred pharmacy during Interdisciplinary Rounds
Emphasize Hospitalists to communicate with RN or AP when printing prescriptions
Hospitalists and Case Management/SWS to start processing medications that need preauthorization prior to the day of discharge
Bring awareness to Pharmacy & Hospitalist teams - to be cognizant of patients on Nebulizer and switch to inhaler upon discharge
Bring awareness to interdisciplinary team members of impact of PDFC data on their practice
Implications for Practice: Completion of the process related to medication upon discharges plays a vital role for improved patient outcomes, can reduce both return visits to the Emergency Department and readmission rates and can maintain higher standards of clinical practice and service excellence, thereby promoting a culture of patient safety. Future plans include: pharmacy and nursing verifying accuracy of patient’s preferred pharmacy during daily rounds, pharmacy tracking and reviewing specific medication cases, Case Management/Social Work Services (SWS) assisting in following-up on medications that need preauthorization and the data being presented at Nursing Operations and Hospitalist Meetings
Diagnostic Medical Errors: Patient\u27s Perspectives on a Pervasive Problem
Introduction. The Institute of Medicine defines diagnostic error as the failure to establish an accurate or timely explanation for the patient\u27s health problem(s), or effectively communicate the explanation to the patient. To our knowledge, no studies exist characterizing diagnostic error from patient perspectives using this definition.
Objective. We sought to characterize diagnostic errors experienced by patients and describe patient perspectives on causes, impacts, and prevention strategies.
Methods. We screened 77 adult inpatients at University of Vermont Medical Center and conducted 27 structured interviews with patients who experienced diagnostic error in the past five years. We performed qualitative analysis using Grounded Theory.
Results. In the past five years, 39% of interviewed patients experienced diagnostic error. The errors mapped to the following categories: accuracy (30%), communication (34%) and timeliness (36%). Poor communication (13 responses) and inadequate time with doctors (7) were the most identified causes of errors. Impacts of errors included emotional distress (17 responses), adverse health outcomes (7) and impaired activities of daily living (6). Patients suggested improved communication (11 responses), clinical management (7) and access to doctors (5) as prevention strategies. For communication, patients rated talk to your doctor highest (mean 8.4, on 1-10 Likert scale) and text message lowest (4.8).
Conclusions/Recommendations. Diagnostic errors are common and have dramatic impact on patients\u27 well-being. We suggest routine surveillance to identify errors, support for patients who have experienced errors, and implementation of patient and provider checklists to enhance communication. Future studies should investigate strategies to allow care providers adequate time with patients.https://scholarworks.uvm.edu/comphp_gallery/1246/thumbnail.jp
Diminished AMPK signaling response to fasting in thioredoxin-interacting protein knockout mice
AbstractThioredoxin-interacting protein (Txnip) knockout (TKO) mice exhibit impaired response to fasting. Herein, we showed that activation of adenine monophosphate-activated protein kinase and cellular AMP levels were diminished in the heart and soleus muscle but not in gastrocnemius muscle of fasting TKO mice. Similarly, glycogen content in fasted TKO mice was increased in oxidative muscles but was not different in glycolytic muscles. These data suggest Txnip deficiency has a higher impact on oxidative muscle than glycolytic muscles and provide new insights into the metabolic role of Txnip
Just Because (Most) Hospitals Are Publishing Charges Does Not Mean Prices Are More Transparent
Background: The Centers for Medicare and Medicaid Services (CMS) recently mandated that all hospitals publish their charge description masters (CDMs) online, in a machine-readable format, by January 1, 2019. In addition, CMS recommended that CDM data be made available in a manner that was consumer friendly and accessible to patients.
Objective: This study aimed to (1) examine all hospitals across the state of Pennsylvania to understand policy compliance and (2) use established metrics to measure accessibility and consumer friendliness of posted CDM data.
Methods: A cross-sectional analysis was conducted to quantify hospital website compliance with the recent CMS policies requiring hospitals to publish their CDM. Data were collected from all Pennsylvania hospital websites. Consumer friendliness was assessed based on searchability, number of website clicks to data, and supplemental educational materials accompanying CDMs such as videos or text.
Results: Most hospitals (189/234, 80.1%) were compliant, but significant variation in data presentation was observed. The mean number of website clicks to the CDM was 3.7 (SD 1.3; range: 1-8). A total of 23.1% of compliant hospitals provided no supplemental educational material with their CDM.
Conclusions: Although disclosure of charges has improved, the data may not be sufficient to meaningfully influence patient decision making
Energy harvesting from transverse galloping
Some elastic bluff bodies under the action of a fluid flow can experience transverse galloping and lose stability if the flow velocity exceeds a critical value. For flow velocities higher than this critical value, there is an energy transfer from the flow to the body and the body develops an oscillatory motion. Usually, it is considered as an undesirable effect for civil or marine structures but here we will show that if the vibration is substantial, it can be used to extract useful energy from the surrounding flow. This paper explores analytically the potential use of transverse galloping in order to obtain energy. To this end, transverse galloping is described by a one-degree-of-freedom model where fluid forces obey the quasi-steady hypothesis. The influence of cross-section geometry and mechanical properties in the energy conversion factor is investigated
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Myocardial hypothermia increases autophagic flux, mitochondrial mass and myocardial function after ischemia-reperfusion injury.
Animal studies have demonstrated beneficial effects of therapeutic hypothermia on myocardial function, yet exact mechanisms remain unclear. Impaired autophagy leads to heart failure and mitophagy is important for mitigating ischemia/reperfusion injury. This study aims to investigate whether the beneficial effects of therapeutic hypothermia are due to preserved autophagy and mitophagy. Under general anesthesia, the left anterior descending coronary artery of 19 female farm pigs was occluded for 90 minutes with consecutive reperfusion. 30 minutes after reperfusion, we performed pericardial irrigation with warm or cold saline for 60 minutes. Myocardial tissue analysis was performed one and four weeks after infarction. Therapeutic hypothermia induced a significant increase in autophagic flux, mitophagy, mitochondrial mass and function in the myocardium after infarction. Cell stress, apoptosis, inflammation as well as fibrosis were reduced, with significant preservation of systolic and diastolic function four weeks post infarction. We found similar biochemical changes in human samples undergoing open chest surgery under hypothermic conditions when compared to the warm. These results suggest that autophagic flux and mitophagy are important mechanisms implicated in cardiomyocyte recovery after myocardial infarction under hypothermic conditions. New therapeutic strategies targeting these pathways directly could lead to improvements in prevention of heart failure
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