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Bui D, Hayward G, Chen TH, Apruzzese P, Asher S, Maslow M, Gorgone M, Hunter C, Flaherty D, Kendall M, Maslow A. Hemodynamic Monitoring In The Cardiac Surgical Patient: Comparison of Three Arterial Catheters. J Cardiothorac Vasc Anesth 2024; 38:1115-1126. [PMID: 38461034 DOI: 10.1053/j.jvca.2024.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 02/05/2024] [Accepted: 02/08/2024] [Indexed: 03/11/2024]
Abstract
OBJECTIVE Systemic systolic (SAP) and mean (MAP) arterial pressure monitoring is the cornerstone in hemodynamic management of the cardiac surgical patient, and the radial artery is the most common site of catheter placement. The present study compared 3 different arterial line procedures. It is hypothesized that a 20-G 12.7- cm catheter inserted into the radial artery will be equal to a 20-G 12.7- cm angiocath placed in the brachial artery, and superior to a 20-G 5.00 cm angiocath placed in the radial artery. DESIGN A prospective randomized control study was performed. SETTING Single academic university hospital. PARTICIPANTS Adult patients ≥18 years old undergoing nonemergent cardiac surgery using cardiopulmonary bypass (CPB). INTERVENTIONS After approval by the Rhode Island Hospital institutional review board, a randomized prospective control study to evaluate 3 different peripheral intraarterial catheter systems was performed: (1) Radial Short (RS): 20-G 5- cm catheter; (2) Radial Long (RL): 20-G 12- cm catheter; and (3) Brachial Long (BL): 20-G 12- cm catheter. MEASUREMENTS AND RESULTS Gradients between central aortic and peripheral catheters (CA-P) were compared and analyzed before CPB and 2 and 10 minutes after separation from CPB. The placement of femoral arterial lines and administration of vasoactive medications were recorded. After exclusions, 67 BL, 61 RL, and 66 RS patients were compared. Before CPB, CA-P SAP and MAP gradients were not significant among the 3 groups. Two minutes after CPB, the CA-P SAP gradient was significant for the RS group (p = 0.005) and insignificant for BL (p = 0.47) and RL (p = 0.39). Two-group analysis revealed that CA-P SAP gradients are similar between BL and RL (p = 0.84), both of which were superior to RS (p = 0.02 and p = 0.04, respectively). At 10 minutes after CPB, the CA-P SAP gradient for RS remained significant (p = 0.004) and similar to the gradient at 2 minutes. The CA-P SAP gradients increased from 2 to 10 minutes for BL (p = 0.13) and RL (p = 0.06). Two minutes after CPB, the CA-P MAP gradients were significant for the BL (p = 0.003), RL (p < 0.0001), and RS (p < 0.0001) groups. Two-group analysis revealed that the CA-P MAP gradients were lower for the BL group compared with the RL (p = 0.054) and RS (p< 0.05) groups. Ten minutes after CPB, the CA-P MAP gradients in the RL and RS groups remained significant (p < 0.0001) and both greater than the BL group (p = 0.002). A femoral arterial line was placed more frequently in the RS group (8/66 = 12.1%) than in the RL group (3/61 = 4.9%) and the BL group (2/67 = 3.0%). Vasopressin was administered significantly more frequently in the RS group. CONCLUSION Regarding CA-P SAP gradients, the RL group performed equally to the BL group, both being superior to RS. Regarding CA-P MAP gradients, BL was superior to RL and RS. Clinically, femoral line placement and vasopressin administration were fewer for the BL and RL groups when compared with the RS group. This study demonstrated the benefits of a long (12.7 cm) 20- G angiocath placed in the radial artery.
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Affiliation(s)
- Danny Bui
- Departments of Anesthesiology, Rhode Island Hospital, Providence, RI
| | - Geoffrey Hayward
- Departments of Anesthesiology, Rhode Island Hospital, Providence, RI
| | - Tzong Huei Chen
- Departments of Anesthesiology, Rhode Island Hospital, Providence, RI
| | | | - Shyamal Asher
- Departments of Anesthesiology, Rhode Island Hospital, Providence, RI
| | | | - Michelle Gorgone
- Departments of Anesthesiology, Rhode Island Hospital, Providence, RI
| | - Caroline Hunter
- Departments of Anesthesiology, Rhode Island Hospital, Providence, RI
| | - Devon Flaherty
- Departments of Anesthesiology, Rhode Island Hospital, Providence, RI
| | - Mark Kendall
- Departments of Anesthesiology, Rhode Island Hospital, Providence, RI
| | - Andrew Maslow
- Departments of Anesthesiology, Rhode Island Hospital, Providence, RI.
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John KN, Cradeur M, Hayward G, Asher S. Caught by POCUS: Post-TAVR Pericardial Effusion. R I Med J (2013) 2024; 107:29-31. [PMID: 38166074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/04/2024]
Abstract
Point-of-care ultrasound (POCUS) is becoming increasingly popular in the field of anesthesiology and is being incorporated into anesthesia resident education. Ultrasound provides a portable, quick, and inexpensive diagnostic tool to help guide clinicians in their decision making and management of medically complex patients. One important utilization of POCUS is helping to guide management of undifferentiated hypotension. We present a case of a patient who underwent a Transcatheter Aortic Valve Replacement (TAVR) procedure who then suffered from hypotension in the post-anesthesia care unit (PACU). POCUS was used to help identify the cause of the patient's hypotension and led to the diagnosis of a pericardial effusion.
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Affiliation(s)
- Kenneth N John
- Department of Anesthesiology at Rhode Island Hospital; Warren Alpert Medical School of Brown University, Providence, RI
| | - Michael Cradeur
- Department of Anesthesiology at Rhode Island Hospital; Warren Alpert Medical School of Brown University, Providence, RI
| | - Geoffrey Hayward
- Department of Anesthesiology at Rhode Island Hospital; Warren Alpert Medical School of Brown University, Providence, RI
| | - Shyamal Asher
- Department of Anesthesiology at Rhode Island Hospital; Warren Alpert Medical School of Brown University, Providence, RI
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Walsh KL, Yadav A, Cradeur M, Huang H, Lee D, Owusu-Dapaah H, Ji C, Kendall MC, Asher S. Impact of a Preclinical Medical Student Anesthesiology Elective on the Attitudes and Perceptions of Medical Students Regarding Anesthesiology. Adv Med Educ Pract 2023; 14:1347-1355. [PMID: 38050578 PMCID: PMC10693776 DOI: 10.2147/amep.s427974] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 11/21/2023] [Indexed: 12/06/2023]
Abstract
Purpose First- and second-year medical students typically have limited exposure to the field of anesthesiology, yet recent match data shows growing interest in the specialty. Early, structured exposure to anesthesiology in the form of a preclinical elective may allow medical students to make more informed decisions on their specialty of choice. Methods The anesthesiology preclinical elective, BIOL 6704: "Anesthesia: Much More than Putting you to Sleep", is a one-credit course taught at The Warren Alpert Medical School of Brown University. A survey consisting of fifteen questions assessing changes in attitudes, perceptions, and interest in anesthesiology was distributed to first- and second-year medical students before and after course participation. The results were analyzed using the Wilcoxon's signed-rank test for paired samples. Results The biggest impact of the preclinical elective was observed in the students' subjective understanding of key aspects of the practice of anesthesiology. Statistically significant improvement was seen in the understanding of airway management, anesthetic pharmacology, basics of ultrasound, vascular access, anesthesiology subspecialties, and an understanding of anesthesiology residency. Overall, results were limited by our small sample size. Conclusion Our elective allows medical students to explore anesthesiology early in their medical school career. After taking this course, students noted more familiarity with various topics in anesthesiology. Peer institutions lacking a similar course may consider using our experience to increase interest about the specialty of anesthesiology for future students.
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Affiliation(s)
- Kendra L Walsh
- The Warren Alpert Medical School of Brown University, Providence, RI, 02903, USA
- Pharmacy Services, Rhode Island Hospital, Providence, RI, 02903, USA
| | - Abhishek Yadav
- Department of Anesthesiology, Rhode Island Hospital, Providence, RI, 02903, USA
| | - Michael Cradeur
- The Warren Alpert Medical School of Brown University, Providence, RI, 02903, USA
| | - Henry Huang
- Department of Anesthesiology, Rhode Island Hospital, Providence, RI, 02903, USA
| | - Daniel Lee
- Department of Anesthesiology, Rhode Island Hospital, Providence, RI, 02903, USA
| | - Harry Owusu-Dapaah
- Department of Anesthesiology, Rhode Island Hospital, Providence, RI, 02903, USA
| | - Chao Ji
- Department of Anesthesiology, Rhode Island Hospital, Providence, RI, 02903, USA
| | - Mark C Kendall
- The Warren Alpert Medical School of Brown University, Providence, RI, 02903, USA
- Department of Anesthesiology, Rhode Island Hospital, Providence, RI, 02903, USA
| | - Shyamal Asher
- The Warren Alpert Medical School of Brown University, Providence, RI, 02903, USA
- Department of Anesthesiology, Rhode Island Hospital, Providence, RI, 02903, USA
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Asher S, Shah R, Ings S, Horder J, Newrick F, Nesr G, Kesse Adu R, Streetly M, Trompeter S, Lee L, Wisniowski B, Mahmood S, Xu K, Papanikalaou X, McMillan A, Popat R, Yong K, Sive J, Kyriakou C, Rabin N. Haematopoietic stem cell mobilisation followed by high-dose chemotherapy and autologous stem cell transplantation for patients with sickle cell disease and myeloma. Br J Haematol 2023; 202:1224-1227. [PMID: 37488061 DOI: 10.1111/bjh.18990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 06/12/2023] [Accepted: 07/10/2023] [Indexed: 07/26/2023]
Affiliation(s)
- S Asher
- Department of Haematology, University College Hospital London NHS Foundation Trust, London, UK
| | - R Shah
- Department of Haematology, University College Hospital London NHS Foundation Trust, London, UK
| | - S Ings
- Department of Haematology, University College Hospital London NHS Foundation Trust, London, UK
| | - J Horder
- Department of Haematology, University College Hospital London NHS Foundation Trust, London, UK
| | - F Newrick
- Department of Haematology, University College Hospital London NHS Foundation Trust, London, UK
| | - G Nesr
- Department of Haematology, University College Hospital London NHS Foundation Trust, London, UK
| | - R Kesse Adu
- Department of Haematology, Guys and St Thomas' NHS Foundation Trust, London, UK
| | - M Streetly
- Department of Haematology, Guys and St Thomas' NHS Foundation Trust, London, UK
| | - S Trompeter
- Department of Haematology, University College Hospital London NHS Foundation Trust, London, UK
| | - L Lee
- Department of Haematology, University College Hospital London NHS Foundation Trust, London, UK
| | - B Wisniowski
- Department of Haematology, University College Hospital London NHS Foundation Trust, London, UK
| | - S Mahmood
- Department of Haematology, University College Hospital London NHS Foundation Trust, London, UK
| | - K Xu
- Department of Haematology, University College Hospital London NHS Foundation Trust, London, UK
| | - X Papanikalaou
- Department of Haematology, University College Hospital London NHS Foundation Trust, London, UK
| | - A McMillan
- Department of Haematology, University College Hospital London NHS Foundation Trust, London, UK
| | - R Popat
- Department of Haematology, University College Hospital London NHS Foundation Trust, London, UK
| | - K Yong
- Department of Haematology, University College Hospital London NHS Foundation Trust, London, UK
| | - J Sive
- Department of Haematology, University College Hospital London NHS Foundation Trust, London, UK
| | - C Kyriakou
- Department of Haematology, University College Hospital London NHS Foundation Trust, London, UK
| | - N Rabin
- Department of Haematology, University College Hospital London NHS Foundation Trust, London, UK
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Asher S, Maslow A, Mishra V, Flaherty D, Hayward G, Whiteneck S, Cheves T, Sweeney J. A Pilot Study to Assess the Clinical Onset of IV Heparin in Interventional Cardiology and Cardiac Surgery. J Cardiothorac Vasc Anesth 2022; 36:4281-4288. [PMID: 36100498 DOI: 10.1053/j.jvca.2022.07.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 07/27/2022] [Accepted: 07/29/2022] [Indexed: 11/11/2022]
Abstract
OBJECTIVES To determine the onset of heparin anticoagulation, using 2 different measures of activated clotting times (ACT), thromboelastography (TEG; R-time), and anti-Xa levels, after administering low- (100 U/kg) and high- (300 U/kg) dose intravenous (IV) heparin to patients undergoing transcatheter aortic valve replacement (TAVR) and cardiac surgery, respectively. DESIGN Prospective study. SETTING Single academic institution. PARTICIPANTS Patients with normal baseline coagulation presenting for TAVR or cardiac valve surgery. INTERVENTIONS Coagulation studies were performed at baseline, 30 seconds, 90 seconds, and 180 seconds after IV heparin administration. The tests included iSTAT (iACT) and Hemochron ACT (hACT), TEG R-Time, and anti-Xa levels. At the authors' institution, anti-Xa is the preferred measure of heparin anticoagulation when time permits. ACT, a rapid point- of-care test, is used to assess intraprocedural anticoagulation. MEASUREMENTS AND MAIN RESULTS After both low- and high-dose heparin, there are peak increases in ACT and anti-Xa at 30 seconds, followed by a decline at 90 seconds and plateau at 180 seconds. The TEG R-time remained elevated (>80 minutes) throughout. For TAVR cases, all anti-Xa was >1.5 IU/mL, and was associated with an iACT >180 seconds and an hACT >200 seconds. For cardiac valve surgery cases, all anti-Xa was >2.4 and associated with an iACT >420 seconds and and hACT >340 seconds. Compared with hACT, iACTs were significantly lower at all time points after low-dose heparin, but not after high-dose heparin. CONCLUSIONS In this pilot study, heparin anticoagulation was detected as early as 30 seconds after IV administration, based on ACT, anti-Xa levels, and TEG R-time.
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Affiliation(s)
- Shyamal Asher
- Department of Anesthesiology, Rhode Island Hospital, Providence, RI.
| | - Andrew Maslow
- Department of Anesthesiology, Rhode Island Hospital, Providence, RI
| | - Vikas Mishra
- Department of Anesthesiology, Rhode Island Hospital, Providence, RI
| | - Devon Flaherty
- Department of Anesthesiology, Rhode Island Hospital, Providence, RI
| | - Geoffrey Hayward
- Department of Anesthesiology, Rhode Island Hospital, Providence, RI
| | | | - Tracey Cheves
- Department of Hematology, Rhode Island Hospital, Providence, RI
| | - Joseph Sweeney
- Department of Hematology, Rhode Island Hospital, Providence, RI
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Asher S, Maslow A, Black R. “Assessment of the MitraClip procedure: Reassessing the goals”. J Cardiothorac Vasc Anesth 2022; 37:812-820. [PMID: 36402648 DOI: 10.1053/j.jvca.2022.10.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 10/21/2022] [Indexed: 11/07/2022]
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Hayward G, Asher S, Gebhardt B, Maslow A. Right Ventricular Assessment: Are Regional Longitudinal Measurements of Value? J Cardiothorac Vasc Anesth 2020; 34:2148-2151. [DOI: 10.1053/j.jvca.2020.03.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 03/03/2020] [Indexed: 11/11/2022]
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Gebhardt BR, Asher S, Maslow A. The Limitations of Using Transthoracic Echocardiographic-Derived Normative Values for Grading Intraoperative Transesophageal Echocardiography Examinations of the Right Ventricle: Are They Really Interchangeable? J Cardiothorac Vasc Anesth 2020; 34:1260-1262. [PMID: 32178955 DOI: 10.1053/j.jvca.2020.02.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 02/13/2020] [Indexed: 11/11/2022]
Affiliation(s)
- Brian R Gebhardt
- Department of Anesthesiology and Perioperative Medicine, Tufts Medical Center, Boston, MA; Anesthesia Associates of New Mexico, Albuquerque, NM.
| | - Shyamal Asher
- Department of Anesthesiology, Rhode Island Hospital, Lifespan Medical Center Warren Alpert School of Medicine at Brown University, Providence Rhode Island
| | - Andrew Maslow
- Department of Anesthesiology, Rhode Island Hospital, Lifespan Medical Center Warren Alpert School of Medicine at Brown University, Providence Rhode Island
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Hannen R, Asher S, Mannella V, Purdie K, Leigh I, Philpott M. 131 Stressed out keratinocytes, new insights into psoriasis lesion formation. J Invest Dermatol 2017. [DOI: 10.1016/j.jid.2017.07.441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Burke J, Shatkar V, Parkinson A, Asher S, Almoudaris A, Huang J. TEMS experience from a tertiary referral centre. Int J Surg 2016. [DOI: 10.1016/j.ijsu.2016.08.177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Dulay G, Asher S. FRI0180 Do Shared Care Schemes Work for Methotrexate Monitoring?: Table 1. Ann Rheum Dis 2014. [DOI: 10.1136/annrheumdis-2014-eular.1311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Leber M, He C, Akhtar S, Asher S, Bania T, Di C, Steinberg E, Webster A, Clark M. 111 A Comparison of Individualized Feedback Versus Standard Didactic Lecture to Teach Interpersonal Communication Skills to Emergency Medicine Residents: A Multicenter Randomized Controlled Trial. Ann Emerg Med 2012. [DOI: 10.1016/j.annemergmed.2012.06.088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Abstract
AbstractCdTe/CdS solar cells have demonstrated stability over thousands of hours of field testing, but have not yet established the same track record for reliability achieved by crystalline Si PV modules. In order to identify potential degradation mechanisms, this paper describes a series of experiments in which CdTe/CdS solar cells are subjected to combinations of temperature, voltage and illumination levels intended to stress the devices beyond levels which would be experienced in the field. During this process the devices display decreases in Voc and FF which are tentatively attributed to chemical changes at the low resistance contact to the CdTe and to changes in the electrical transport properties of the CdTe. Two thermally activated effects were observed depending upon stress bias. Reverse bias appears to degrade bulk CdTe electrical properties while forward bias strengthens a reverse diode which most likely is located at the back contact. Chemical analysis of the back contact region of the devices using XPS reveals strong oxide peaks in all stressed samples. Evidence of Cd diffusion into the Mo contacts is observed by SIMS and Auger. Mo diffusion into the CdTe is promoted by reverse bias stressing. Cu migration consistent with positively charged ions was indicated by SIMS.
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Rose DH, Albin DS, Matson RJ, Swartzlander AB, Li XS, Dhere RG, Asher S, Hasoon FS, Sheldon P. Effects of Oxygen During Close-Spaced Sublimation of CdTe Solar Cells. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-426-337] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AbstractThe presence of oxygen during close-spaced sublimation (CSS) deposition of CdTe has been regarded as necessary for high-efficiency CdS/CdTe solar cells. To date, research has focused on the effect of oxygen on the acceptor density in the CdTe absorber. We find that although oxygen may influence the doping density, a perhaps more significant effect is its influence on nucleation and growth of the film. Oxygen partial pressures of 0 to 24 torr and total pressures of 5 to 45 torr (balance He) have been explored for CSS depositions. We find that increasing the O2 partial pressure increases the density of CdTe nucleation sites, thereby suppressing pinhole formation and likely reducing defects at the junction. However, increasing O2 also tends to decrease grain size and faceting in the films. In addition to influencing the film properties, O2 adversely affects the source material, producing non-uniformly oxidized surfaces that reduce deposition rates and impair device uniformity and run-to-run reproducibility.We have also determined that the graphite susceptors typically used with CSS deposition convert a portion of the oxygen ambient to CO and CO2 during deposition. The amount converted is highly dependent on the type and age of the graphite susceptor used. The COx byproducts are not efficiently incorporated in the CdTe film and do not influence the deposition as oxygen does. We describe the effect of the changing oxygen partial pressure during the course of deposition. Finally, we report high-efficiency solar cells (12.8% AM 1.5) made without oxygen.
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Albin D, Dhere R, Wu X, Gessert T, Romero M, Yan Y, Asher S. Perturbation of Copper Substitutional Defect Concentrations in CdS/CdTe Heterojunction Solar Cell Devices. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-719-f8.34] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AbstractThe efficacy of implementing terrestrial-based photovoltaics is dictated by trade-offs in device performance, cost, and reliability. Presently, the highest efficiency polycrystalline CdS/CdTe superstrate solar cells utilize back contacts containing copper as an intentional dopant. Accelerated stress data correlates copper diffusion from this contact with performance degradation. Degradation at the device level exhibits two characteristic modes that are influenced by CdTe surface treatments prior to contacting. Rapid degradation associated with a rapidly decreasing open-circuit voltage can occur in cases where processing favors stoichiometric CdTe surfaces. Slower degradation associated with roll-over is typified by treatments favoring the presence of Te at the back contact. The chemical composition and extent of Te-rich contact interfaces is revealed by transmission electron microscopy. Deep-level transient spectroscopy of NP etched and non-etched devices show Te-rich conditions are necessary for the detection of deep-acceptor CuCd defect levels at (Ev +0.28 to 0.34 eV). Low keV cathodoluminescence measurements show that these defects can be found localized at the back surface of CdS/CdTe devices.
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Bell IR, Markley EJ, King DS, Asher S, Marby D, Kayne H, Greenwald M, Ogar DA, Margen S. Polysymptomatic syndromes and autonomic reactivity to nonfood stressors in individuals with self-reported adverse food reactions. J Am Coll Nutr 1993; 12:227-38. [PMID: 8409077 DOI: 10.1080/07315724.1993.10718304] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
This study compared symptom reports and cardiovascular reactivity of a group of 24 individuals recruited from the community who reported a cognitive or emotional symptom caused by at least one food (food-sensitivity reporters, FSR) vs those of 15 controls (C) without a history of food, chemical, drug, or inhalant sensitivities. The main findings were: 1) FSR indicated sensitivities not only to foods, but also to environmental chemicals, drugs, and natural inhalants, as well as significantly more symptoms than C in multiple systems; 2) more FSR than C noted recent state depression and anxiety, as well as higher trait anxiety on the Bendig form of the Taylor Manifest Anxiety Scale; 3) however, on multiple regression analysis, not only depression, but also the number of sensitivities (foods, chemicals, drugs, inhalants), accounted for part of the variance in total number of symptoms (38 and 17%, respectively), whereas none of the affective measures accounted for any of the variance in total number of sensitivities over all subjects; 4) after controlling for depression and anxiety, FSR still showed a trend toward poorer performance on a timed mental arithmetic task (p = 0.16); and 5) FSR and C showed opposite patterns of heart rate change to two different stressful tasks (mental arithmetic and isometric exercise) (group by task interaction, p < 0.05). The data are discussed in terms of a time-dependent sensitization (TDS) process that predicts a cross-sensitizing and cross-reactive role for xenobiotic agents (e.g., foods, chemicals, drugs, and inhalants) and for salient psychological stress in the expression of psychophysiological dysfunctions of FSR. As in other chronically ill populations, negative affect in food-sensitive individuals may explain greater symptom reporting, but not necessarily account for the illness itself. For either a food or a psychological stimulus to begin to elicit sensitized responses, e.g., marked physiological differences from C, FSR may require multiple, intermittent exposures spaced over 5-28 days rather than on only 1 day.
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Affiliation(s)
- I R Bell
- School of Public Health-Nutrition, University of California, Berkeley
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