Thomas Hamelin - Academia.edu (original) (raw)
Papers by Thomas Hamelin
Journal of PeriAnesthesia Nursing, 2019
We evaluate four-gauge-particle tree level scattering amplitudes using the Polyakov string path i... more We evaluate four-gauge-particle tree level scattering amplitudes using the Polyakov string path integral in the proper-time gauge, where the string path integral can be cast into the Feynman-Schwinger propertime representation. We compare the resultant scattering amplitudes, which include α-corrections, with the conventional ones that may be obtained by substituting local vertex operators for the external string states. In the zero-slope limit, both amplitudes are reduced to the four-gauge-particle scattering amplitude of non-Abelian Yang-Mills gauge theory. However, when the string corrections become relevant with finite α , the scattering amplitude in the proper-time gauge differs from the conventional one: The Polyakov string path integral in the proper-time gauge, equivalent to the deformed cubic string field theory, systematically provides the alpha prime corrections. In addition, we find that the scattering amplitude in the proper-time gauge contains tachyon poles in a manner consistent with three-particlescattering amplitudes. The scattering amplitudes evaluated using the Polyakov string path integral in the proper-time gauge may be more suitable than conventional ones for exploring string corrections to the quantum field theories and high energy behaviors of open string.
Journal of Surgical Research, 2019
Background: Surgical supplies occupy a large portion of health care expenditures but is often und... more Background: Surgical supplies occupy a large portion of health care expenditures but is often under the surgeon's control. We sought to assess whether an automated, surgeon-directed, cost feedback system can decrease supply expenditures for five common general surgery procedures. Materials and methods: An automated "surgical receipt" detailing intraoperative supply costs was generated and emailed to surgeons after each case. We compared the median cost per case for 18 mo before and after implementation of the surgical receipt. We controlled for price fluctuations by applying common per-unit prices in both periods. We also compared the incision time, case length booking accuracy, length of stay, and postoperative occurrences.
Journal of PeriAnesthesia Nursing, 2019
We evaluate four-gauge-particle tree level scattering amplitudes using the Polyakov string path i... more We evaluate four-gauge-particle tree level scattering amplitudes using the Polyakov string path integral in the proper-time gauge, where the string path integral can be cast into the Feynman-Schwinger propertime representation. We compare the resultant scattering amplitudes, which include α-corrections, with the conventional ones that may be obtained by substituting local vertex operators for the external string states. In the zero-slope limit, both amplitudes are reduced to the four-gauge-particle scattering amplitude of non-Abelian Yang-Mills gauge theory. However, when the string corrections become relevant with finite α , the scattering amplitude in the proper-time gauge differs from the conventional one: The Polyakov string path integral in the proper-time gauge, equivalent to the deformed cubic string field theory, systematically provides the alpha prime corrections. In addition, we find that the scattering amplitude in the proper-time gauge contains tachyon poles in a manner consistent with three-particlescattering amplitudes. The scattering amplitudes evaluated using the Polyakov string path integral in the proper-time gauge may be more suitable than conventional ones for exploring string corrections to the quantum field theories and high energy behaviors of open string.
Journal of Surgical Research, 2019
Background: Surgical supplies occupy a large portion of health care expenditures but is often und... more Background: Surgical supplies occupy a large portion of health care expenditures but is often under the surgeon's control. We sought to assess whether an automated, surgeon-directed, cost feedback system can decrease supply expenditures for five common general surgery procedures. Materials and methods: An automated "surgical receipt" detailing intraoperative supply costs was generated and emailed to surgeons after each case. We compared the median cost per case for 18 mo before and after implementation of the surgical receipt. We controlled for price fluctuations by applying common per-unit prices in both periods. We also compared the incision time, case length booking accuracy, length of stay, and postoperative occurrences.
Journal of perianesthesia nursing : official journal of the American Society of PeriAnesthesia Nurses, Jan 13, 2018
This paper spotlights human capital management, digital technology, and costs control as issues t... more This paper spotlights human capital management, digital technology, and costs control as issues that healthcare leaders will face in redesigning the health care ecosystem in the 21st century. The paper was designed to highlight the attributes that make effective leaders. It addresses how nursing leadership can take a lead to redesign the 21st Century health care system, supported by case examples. An expansive literature review was done using MEDLINE, SAGE, Google Scholar, and University of California San Diego Library Catalogs. The selections criteria include recent publications in English within and outside the healthcare industry. Health leadership is viewed as paramount to productivity, capacity and meeting new challenges. Effective nursing leadership in a healthcare organization correlates with staff job satisfaction, retention, turnover and quality of care. Nursing leadership development must be supported by appropriate level of educational preparedness, and requisite set of c...
Nursing management, 2018
rganizations working in high wage, developed nations need the competitive strategy of exceptional... more rganizations working in high wage, developed nations need the competitive strategy of exceptional human capital management to achieve profitability. 1 Human capital refers to employees' knowledge and experiences. It has been argued that managing human capital by instinct and intuition is shortsighted , if not reckless. 1 Superior technology and access to capital no longer offer a sustainable advantage. The traditional view of employees as costs in addition to failing to invest in human capital management with opportunities such as leadership development, job design, and knowledge sharing may imperil an organization's success and survival. Five key drivers have
Journal of PeriAnesthesia Nursing, 2017
Healthcare is a global concern among all nations and nursing is a global profession as evidenced ... more Healthcare is a global concern among all nations and nursing is a global profession as evidenced by the flow of healthcare professionals across international boundaries. With English as the language of science and commerce and post-colonial influence in domestic healthcare practice and training, many former Anglo-speaking colonial settlements become parts of an expansive market for health human resources migration. The movement of health personnel mainly flows from low and medium income countries to high income countries to sustain their health systems. The resulting brain drain adversely impacts a source country's health system, leading the World Health Organization to declare global health migration as the biggest health threat of the 21st century. This report illustrates how an overseas health network achieves its goals of developing clinical and management excellence through an international exchange program. The provider institution also fulfills its mission of contributing to a more balanced, equitable and healthier world.
Operative Neurosurgery, 2017
BACKGROUND: Real-time magnetic resonance imaging (MRI) visualization during stereotactic needle b... more BACKGROUND: Real-time magnetic resonance imaging (MRI) visualization during stereotactic needle biopsies affords several valuable benefits to the neurosurgeon, including the opportunity to visually confirm the biopsy site at the time of surgery. Until now, reported experiences with this technique have been limited to the setting of intraoperative MRI or dedicated procedural MRI suites with modified ventilation systems. OBJECTIVE: To describe our experience with 11 consecutive patients who underwent real-time MRI-guided biopsy performed using SmartFrame® stereotaxis (MRI Interventions, Irvine, California) in the setting of a conventional diagnostic MRI suite. METHODS: This is a case series of patients that underwent real-time MRI-guided biopsy at a single institution. RESULTS: Four of the 11 lesions were previously biopsied by experienced neurosurgeons, yielding tissues that were nondiagnostic. Six of these lesions were sub-cubic centimeter in volume. One lesion was associated with a...
Neurosurgical focus, 2016
OBJECTIVE Stereotactic laser ablation (SLA) is typically performed in the setting of intraoperati... more OBJECTIVE Stereotactic laser ablation (SLA) is typically performed in the setting of intraoperative MRI or in a staged manner in which probe insertion is performed in the operating room and thermal ablation takes place in an MRI suite. METHODS The authors describe their experience, in which SLA for glioblastoma (GBM) treatment was performed entirely within a conventional MRI suite using the SmartFrame stereotactic device. RESULTS All 10 patients with GBM (2 with isocitrate dehydrogenase 1 mutation [mIDH1] and 8 with wild-type IDH1 [wtIDH1]) were followed for > 6 months. One of these patients underwent 2 independent SLAs approximately 12 months apart. Biopsies were performed prior to SLA for all patients. There were no perioperative morbidities, wound infections, or unplanned 30-day readmissions. The average time for a 3-trajectory SLA (n = 3) was 436 ± 102 minutes; for a 2-trajectory SLA (n = 4) was 321 ± 85 minutes; and for a single-trajectory SLA (n = 4) was 254 ± 28 minutes. N...
Neurosurgical focus, 2016
OBJECTIVE Therapeutic options for brain metastases (BMs) that recur after stereotactic radiosurge... more OBJECTIVE Therapeutic options for brain metastases (BMs) that recur after stereotactic radiosurgery (SRS) remain limited. METHODS The authors provide the collective experience of 4 institutions where treatment of BMs that recurred after SRS was performed with stereotactic laser ablation (SLA). RESULTS Twenty-six BMs (in 23 patients) that recurred after SRS were treated with SLA (2 patients each underwent 2 SLAs for separate lesions, and a third underwent 2 serial SLAs for discrete BMs). Histological findings in the BMs treated included the following: breast (n = 6); lung (n = 6); melanoma (n = 5); colon (n = 2); ovarian (n = 1); bladder (n = 1); esophageal (n = 1); and sarcoma (n = 1). With a median follow-up duration of 141 days (range 64-794 days), 9 of the SLA-treated BMs progressed despite treatment (35%). All cases of progression occurred in BMs in which < 80% ablation was achieved, whereas no disease progression was observed in BMs in which ≥ 80% ablation was achieved. Five...
Journal of PeriAnesthesia Nursing, 2019
We evaluate four-gauge-particle tree level scattering amplitudes using the Polyakov string path i... more We evaluate four-gauge-particle tree level scattering amplitudes using the Polyakov string path integral in the proper-time gauge, where the string path integral can be cast into the Feynman-Schwinger propertime representation. We compare the resultant scattering amplitudes, which include α-corrections, with the conventional ones that may be obtained by substituting local vertex operators for the external string states. In the zero-slope limit, both amplitudes are reduced to the four-gauge-particle scattering amplitude of non-Abelian Yang-Mills gauge theory. However, when the string corrections become relevant with finite α , the scattering amplitude in the proper-time gauge differs from the conventional one: The Polyakov string path integral in the proper-time gauge, equivalent to the deformed cubic string field theory, systematically provides the alpha prime corrections. In addition, we find that the scattering amplitude in the proper-time gauge contains tachyon poles in a manner consistent with three-particlescattering amplitudes. The scattering amplitudes evaluated using the Polyakov string path integral in the proper-time gauge may be more suitable than conventional ones for exploring string corrections to the quantum field theories and high energy behaviors of open string.
Journal of Surgical Research, 2019
Background: Surgical supplies occupy a large portion of health care expenditures but is often und... more Background: Surgical supplies occupy a large portion of health care expenditures but is often under the surgeon's control. We sought to assess whether an automated, surgeon-directed, cost feedback system can decrease supply expenditures for five common general surgery procedures. Materials and methods: An automated "surgical receipt" detailing intraoperative supply costs was generated and emailed to surgeons after each case. We compared the median cost per case for 18 mo before and after implementation of the surgical receipt. We controlled for price fluctuations by applying common per-unit prices in both periods. We also compared the incision time, case length booking accuracy, length of stay, and postoperative occurrences.
Journal of PeriAnesthesia Nursing, 2019
We evaluate four-gauge-particle tree level scattering amplitudes using the Polyakov string path i... more We evaluate four-gauge-particle tree level scattering amplitudes using the Polyakov string path integral in the proper-time gauge, where the string path integral can be cast into the Feynman-Schwinger propertime representation. We compare the resultant scattering amplitudes, which include α-corrections, with the conventional ones that may be obtained by substituting local vertex operators for the external string states. In the zero-slope limit, both amplitudes are reduced to the four-gauge-particle scattering amplitude of non-Abelian Yang-Mills gauge theory. However, when the string corrections become relevant with finite α , the scattering amplitude in the proper-time gauge differs from the conventional one: The Polyakov string path integral in the proper-time gauge, equivalent to the deformed cubic string field theory, systematically provides the alpha prime corrections. In addition, we find that the scattering amplitude in the proper-time gauge contains tachyon poles in a manner consistent with three-particlescattering amplitudes. The scattering amplitudes evaluated using the Polyakov string path integral in the proper-time gauge may be more suitable than conventional ones for exploring string corrections to the quantum field theories and high energy behaviors of open string.
Journal of Surgical Research, 2019
Background: Surgical supplies occupy a large portion of health care expenditures but is often und... more Background: Surgical supplies occupy a large portion of health care expenditures but is often under the surgeon's control. We sought to assess whether an automated, surgeon-directed, cost feedback system can decrease supply expenditures for five common general surgery procedures. Materials and methods: An automated "surgical receipt" detailing intraoperative supply costs was generated and emailed to surgeons after each case. We compared the median cost per case for 18 mo before and after implementation of the surgical receipt. We controlled for price fluctuations by applying common per-unit prices in both periods. We also compared the incision time, case length booking accuracy, length of stay, and postoperative occurrences.
Journal of perianesthesia nursing : official journal of the American Society of PeriAnesthesia Nurses, Jan 13, 2018
This paper spotlights human capital management, digital technology, and costs control as issues t... more This paper spotlights human capital management, digital technology, and costs control as issues that healthcare leaders will face in redesigning the health care ecosystem in the 21st century. The paper was designed to highlight the attributes that make effective leaders. It addresses how nursing leadership can take a lead to redesign the 21st Century health care system, supported by case examples. An expansive literature review was done using MEDLINE, SAGE, Google Scholar, and University of California San Diego Library Catalogs. The selections criteria include recent publications in English within and outside the healthcare industry. Health leadership is viewed as paramount to productivity, capacity and meeting new challenges. Effective nursing leadership in a healthcare organization correlates with staff job satisfaction, retention, turnover and quality of care. Nursing leadership development must be supported by appropriate level of educational preparedness, and requisite set of c...
Nursing management, 2018
rganizations working in high wage, developed nations need the competitive strategy of exceptional... more rganizations working in high wage, developed nations need the competitive strategy of exceptional human capital management to achieve profitability. 1 Human capital refers to employees' knowledge and experiences. It has been argued that managing human capital by instinct and intuition is shortsighted , if not reckless. 1 Superior technology and access to capital no longer offer a sustainable advantage. The traditional view of employees as costs in addition to failing to invest in human capital management with opportunities such as leadership development, job design, and knowledge sharing may imperil an organization's success and survival. Five key drivers have
Journal of PeriAnesthesia Nursing, 2017
Healthcare is a global concern among all nations and nursing is a global profession as evidenced ... more Healthcare is a global concern among all nations and nursing is a global profession as evidenced by the flow of healthcare professionals across international boundaries. With English as the language of science and commerce and post-colonial influence in domestic healthcare practice and training, many former Anglo-speaking colonial settlements become parts of an expansive market for health human resources migration. The movement of health personnel mainly flows from low and medium income countries to high income countries to sustain their health systems. The resulting brain drain adversely impacts a source country's health system, leading the World Health Organization to declare global health migration as the biggest health threat of the 21st century. This report illustrates how an overseas health network achieves its goals of developing clinical and management excellence through an international exchange program. The provider institution also fulfills its mission of contributing to a more balanced, equitable and healthier world.
Operative Neurosurgery, 2017
BACKGROUND: Real-time magnetic resonance imaging (MRI) visualization during stereotactic needle b... more BACKGROUND: Real-time magnetic resonance imaging (MRI) visualization during stereotactic needle biopsies affords several valuable benefits to the neurosurgeon, including the opportunity to visually confirm the biopsy site at the time of surgery. Until now, reported experiences with this technique have been limited to the setting of intraoperative MRI or dedicated procedural MRI suites with modified ventilation systems. OBJECTIVE: To describe our experience with 11 consecutive patients who underwent real-time MRI-guided biopsy performed using SmartFrame® stereotaxis (MRI Interventions, Irvine, California) in the setting of a conventional diagnostic MRI suite. METHODS: This is a case series of patients that underwent real-time MRI-guided biopsy at a single institution. RESULTS: Four of the 11 lesions were previously biopsied by experienced neurosurgeons, yielding tissues that were nondiagnostic. Six of these lesions were sub-cubic centimeter in volume. One lesion was associated with a...
Neurosurgical focus, 2016
OBJECTIVE Stereotactic laser ablation (SLA) is typically performed in the setting of intraoperati... more OBJECTIVE Stereotactic laser ablation (SLA) is typically performed in the setting of intraoperative MRI or in a staged manner in which probe insertion is performed in the operating room and thermal ablation takes place in an MRI suite. METHODS The authors describe their experience, in which SLA for glioblastoma (GBM) treatment was performed entirely within a conventional MRI suite using the SmartFrame stereotactic device. RESULTS All 10 patients with GBM (2 with isocitrate dehydrogenase 1 mutation [mIDH1] and 8 with wild-type IDH1 [wtIDH1]) were followed for > 6 months. One of these patients underwent 2 independent SLAs approximately 12 months apart. Biopsies were performed prior to SLA for all patients. There were no perioperative morbidities, wound infections, or unplanned 30-day readmissions. The average time for a 3-trajectory SLA (n = 3) was 436 ± 102 minutes; for a 2-trajectory SLA (n = 4) was 321 ± 85 minutes; and for a single-trajectory SLA (n = 4) was 254 ± 28 minutes. N...
Neurosurgical focus, 2016
OBJECTIVE Therapeutic options for brain metastases (BMs) that recur after stereotactic radiosurge... more OBJECTIVE Therapeutic options for brain metastases (BMs) that recur after stereotactic radiosurgery (SRS) remain limited. METHODS The authors provide the collective experience of 4 institutions where treatment of BMs that recurred after SRS was performed with stereotactic laser ablation (SLA). RESULTS Twenty-six BMs (in 23 patients) that recurred after SRS were treated with SLA (2 patients each underwent 2 SLAs for separate lesions, and a third underwent 2 serial SLAs for discrete BMs). Histological findings in the BMs treated included the following: breast (n = 6); lung (n = 6); melanoma (n = 5); colon (n = 2); ovarian (n = 1); bladder (n = 1); esophageal (n = 1); and sarcoma (n = 1). With a median follow-up duration of 141 days (range 64-794 days), 9 of the SLA-treated BMs progressed despite treatment (35%). All cases of progression occurred in BMs in which < 80% ablation was achieved, whereas no disease progression was observed in BMs in which ≥ 80% ablation was achieved. Five...