Ongoing Aggregate Safety Evaluation (OASE) is a key business imperative in enabling the clinical ... more Ongoing Aggregate Safety Evaluation (OASE) is a key business imperative in enabling the clinical safety model. Integrated data specification and derivation are key parts of the necessary data pooling strategy. Currently, data integration at the compound level faces many challenges. Due to a drug’s development history, variable attributes, such as name, type, and length, frequently are inconsistent across studies. Thus, when datasets are pooled for an aggregate analysis, programmers need to check the datasets and make conversions manually so that the attributes are consistent. Differences in variable name and type can cause inaccuracies, such as missing values, and differences in length can potentially cause truncation of the variable value if it is not checked thoroughly. These tasks are very time consuming and tedious, and there is the possibility of human error. The key to enable the OASE is to efficiently integrate the trial-level data to compound level in an automated fashion. T...
The Enclosed Gardens of Mechelen are beautiful examples of historical mixed-media objects. Since ... more The Enclosed Gardens of Mechelen are beautiful examples of historical mixed-media objects. Since they are extremely fragile, vibrations are considered a major agent of deterioration. To prepare and evaluate their permanent exhibition and to support decision making for future loans, three experiments were performed to estimate the vibrational impact. of transport was considered. A truck transport of three Gardens to a temporary exhibition was monitored and the condition of the Gardens was documented before and after transport. Finally, a vibrational assessment was performed on the permanent display.
Certain phenome r ^ c 9sociated with the radiation characteristics of directional ae_teb ,as, of ... more Certain phenome r ^ c 9sociated with the radiation characteristics of directional ae_teb ,as, of particular practical importance in communications engineering, are carefully defined and dealt with in detail. In tie measurement of the radiation c4h.aracte-ris'_tc: , only the coax)'.a"_ system ( 6 p -0-coaxial ca;^le ) is used, as this gives v. tfte smallest error, and in the measurement of t,'Ie casrection?l diagr'az:-: oni'S, the normalidiagram, is LaKen, as the.ormai:-zed rep re sentati,-is generally val-,English translation11 pages. 0r1g. art, has f or: Ides, i to and 7 figures.
Contemporary Biostatistics with Biopharmaceutical Applications
The vector autoregressive (VAR) and vector autoregressive moving average (VARMA) models have been... more The vector autoregressive (VAR) and vector autoregressive moving average (VARMA) models have been widely used to model multivariate time series, because of their capability to represent the dynamic relationships among variables in a system and their usefulness in forecasting unknown future values. However, when the dimension is very high, the number of parameters often exceed the number of available observations, and it is impossible to estimate the parameters. A suitable solution is clearly needed. After introducing some existing methods, we will suggest the use of contemporal aggregation as a dimension reduction method, which is very natural and simple to use. We will compare our proposed method with other existing methods in terms of forecast accuracy through both simulations and empirical examples. The presentation is based on the invited talk at the 2017 ICSA Applied Statistics Symposium in Chicago.
Abstract We consider the impacts of spatial aggregation on the model parameters and forecasts of ... more Abstract We consider the impacts of spatial aggregation on the model parameters and forecasts of the space-time autoregressive moving-average (STARMA) model. In particular, we focus on poolability, the equality of mean squared forecast error of the aggregate variable from both the non-aggregate and aggregate models, where the same model order is assumed because a model order is often unchanged under spatial aggregation, which is different from temporal aggregation. For VARMA models, there exists conditions for poolability with known parameters and a test for poolability when parameters are not known. However, this test does not apply to STARMA models due to the restricted form of their parameter matrices. In focusing on the STARMA model, we show how the aggregate model parameters are functions of the non-aggregate model parameters under poolability. In addition, we develop three poolability tests that apply to any STARMA model. We demonstrate these tests through an empirical example involving urban crime data.
Questions concerning the mechanical properties and the mechanical testing of materials come up of... more Questions concerning the mechanical properties and the mechanical testing of materials come up often in conservation practice. However, the engineering concepts of mechanical properties do not generally appear in conservation training curricula, where chemistry, and to some extent, physics, dominate the training in the natural sciences. Over the past decade, the RCE has developed a one to two day workshop on the subject as part of the basic science curricula in two conservationtraining programs. It provides conservation students with the background to deal with basic issues of the strength of materials and adhesives in their work. The workshop is based on two concepts: 1) teaching the “foreign” technical language of mechanical properties and relating that to everyday laymen’s terms, and 2) having students perform simple mechanical tests which can eventually be used in the conservation studio, without the need for complex and expensive equipment.
ABSTRACT Vibrations due to heavy construction work continue to be a major concern for museums. Al... more ABSTRACT Vibrations due to heavy construction work continue to be a major concern for museums. Although there has been an increase in research on the effect of vibrations on objects of cultural heritage in recent years, selecting measures to protect collections and remain open during construction work continues to be difficult because of a lack of data on what objects can actually withstand, the complexity of vibration loads, and the uniqueness of each situation. The major renovation of the Central Library in Liverpool, UK, which shared walls with the World Museum and Walker Art Gallery, both of which belong within National Museums Liverpool, showed how museums and other institutions can successfully deal with such situations. An integral approach was taken, beginning with an extensive risk analysis to determine which objects could remain on display, which needed extra protection and regular condition monitoring, and which had to be removed. The museums then negotiated a vibration protocol and action plan with the contractors, including continuous monitoring, and trigger levels requiring consultation or work stoppage. Vibration data were also stored and used for later analysis. This integral approach was successful in protecting the collections on exhibition, with only two incidents of reported damage directly related to vibrations. A combination of museum staff experience, excellent communications with the contractors, and some flexibility in defining vibration limits provided a successful recipe for both museums. The analysis of the vibration data using the basic engineering concept of the Palmgren-Miner rule, supports a more flexible approach to setting vibration limits based on recently published guidelines.
To investigate the role of indocyanine green (ICG) lymphangiography in the reduction of drainage ... more To investigate the role of indocyanine green (ICG) lymphangiography in the reduction of drainage after neck dissection. Patients with oral cavity squamous cell carcinoma were randomized into Group A (study group) and Group B (control). In the study group, upon the completion of neck dissection, a total of 2.5 mg of ICG was injected submucosally at the four quadrants around the tumour. Another 2.5 mg of ICG was injected subdermally in the groin bilaterally. The neck was screened using Near Infrared fluorescence. The presence of lymphatic leakage was noted and plicated with silk stitches. The total drainage volume of post-operative day 1, day 2 and the total accumulated volume until drain removal was measured. Twenty-two patients (Group A, n = 12; Group B, n = 10) were recruited. All patients in Group A had at least one site of lymphatic leakage identified. One patient in Group B developed chylous fistula and was excluded from analysis. The mean total drain output for day 1 and 2 afte...
The purpose of this study was to assess the predictability of the American Joint Committee on Can... more The purpose of this study was to assess the predictability of the American Joint Committee on Cancer (AJCC) staging system on patients with stage II recurrent nasopharyngeal carcinoma (NPC). We conducted a retrospective review of the surgical outcome for patients with recurrent NPC and retropharyngeal lymph node (RLN) metastasis (group I), recurrent NPC and parapharyngeal space (PPS) invasion (group II), and recurrent NPC and internal carotid artery (ICA) encasement (group III). Between 1990 and 2013, 145 patients received an operation for stage II recurrent NPC (group I, n = 62; group II, n = 65; and group III, n = 18). The rate of local tumor recurrence was significantly higher in groups II and III. The rate of systemic metastasis was significantly higher in group III (16.7%). Accordingly, the 5-year overall survival was significantly worse for patients in group III (group I: 81.2%; group II: 68.4%; and group III: 48.5%). The significantly worse prognosis of recurrent NPC encasing...
Prospective, observational study to assess the efficacy of salvage nasopharyngectomy for recurren... more Prospective, observational study to assess the efficacy of salvage nasopharyngectomy for recurrent nasopharyngeal carcinoma (NPC) via the endoscopic endonasal approach using a three-dimensional (3D) high-definition endoscopic system. Between 2016 and 2017, 30 patients with recurrent NPC were recruited. Patient demographics, tumor characteristics, and perioperative data were recorded. Instrument ergonomics and perceived advantages were assessed by the operating, assisting, and observing surgeons. The majority (70%) of patients received radiotherapy alone as the initial treatment for NPC, and tumor recurred after a mean interval of 16.8 months. The tumor (T) classifications of the recurrent (R) tumors were: RT1: 46.7%; RT2: 33.3%; and RT3: 20.0%. The mean operative time was 293.3 minutes, and no conversion to open approach was necessary. Internal carotid artery dissection was required in nine patients, and the resection and repair of dura was required in six patients. The most common ...
To report on the feasibility of total laryngopharyngectomy and free jejunal flap transfer for pat... more To report on the feasibility of total laryngopharyngectomy and free jejunal flap transfer for patient with hypopharyngeal cancer via the transoral robotic surgery (TORS) approach. A patient with hypopharyngeal cancer involving the post-cricoid region is used for demonstration of the TORS total laryngopharyngectomy and free jejunal flap reconstruction. The procedure starts with a cruciate incision for terminal tracheostomy. The trachea and cervical esophagus is exposed and transected, making sure that the resection margins are adequate. This is followed by the transoral dissection using the robotic surgical system. The laryngopharyngectomy specimen is delivered and the free jejunal flap is replaced transorally. Jejuno-oesophageal suturing and the microvascular anastomosis are performed through the tracheostomy wound. The remaining pharyngo-jejunal anastomosis is performed transorally via the TORS approach. TORS total laryngopharyngectomy and free jejunal flap reconstruction is feasib...
The essay addresses the question "What is Genealogy?" through a consideration of the value of tra... more The essay addresses the question "What is Genealogy?" through a consideration of the value of traditional genealogical narratives of families for the Chinese state and society, and the implications of their absence for those caught up in the 19th century diaspora to America. Using genealogy as a method of critical inquiry, however, enables scholars to begin studying the significance of this phenomenon in the lives of Chinese immigrants and the centrality of family in safeguarding their legacy. It does this through an examination of the lives of two Chinese community leaders in Denver's Chinatown. It concludes with a call for a horizontal genealogical study of community leaders in order to have a better understanding of who they were and the role they played in Chinese America.
Programmed cell death protein 4 (PDCD4) is a novel tumor suppressor protein involved in programme... more Programmed cell death protein 4 (PDCD4) is a novel tumor suppressor protein involved in programmed cell death. Its association with cancer progression has been observed in multiple tumor models, but evidence supporting its association with solid tumors in humans remains controversial. This study aimed to determine the clinical significance and prognostic value of PDCD4 in solid tumors. A systematic literature review was performed to retrieve publications with available clinical information and survival data. The eligibility of the selected articles was based on the criteria of the Dutch Cochrane Centre proposed by the Meta-analysis Of Observational Studies in Epidemiology group. Pooled odds ratios (ORs), hazard ratios (HRs), and 95% confidence intervals (CIs) for survival analysis were calculated. Publication bias was examined by Begg's and Egger's tests. Clinical data of 2227 cancer patients with solid tumors from 23 studies were evaluated. PDCD4 expression was significantl...
Ongoing Aggregate Safety Evaluation (OASE) is a key business imperative in enabling the clinical ... more Ongoing Aggregate Safety Evaluation (OASE) is a key business imperative in enabling the clinical safety model. Integrated data specification and derivation are key parts of the necessary data pooling strategy. Currently, data integration at the compound level faces many challenges. Due to a drug’s development history, variable attributes, such as name, type, and length, frequently are inconsistent across studies. Thus, when datasets are pooled for an aggregate analysis, programmers need to check the datasets and make conversions manually so that the attributes are consistent. Differences in variable name and type can cause inaccuracies, such as missing values, and differences in length can potentially cause truncation of the variable value if it is not checked thoroughly. These tasks are very time consuming and tedious, and there is the possibility of human error. The key to enable the OASE is to efficiently integrate the trial-level data to compound level in an automated fashion. T...
The Enclosed Gardens of Mechelen are beautiful examples of historical mixed-media objects. Since ... more The Enclosed Gardens of Mechelen are beautiful examples of historical mixed-media objects. Since they are extremely fragile, vibrations are considered a major agent of deterioration. To prepare and evaluate their permanent exhibition and to support decision making for future loans, three experiments were performed to estimate the vibrational impact. of transport was considered. A truck transport of three Gardens to a temporary exhibition was monitored and the condition of the Gardens was documented before and after transport. Finally, a vibrational assessment was performed on the permanent display.
Certain phenome r ^ c 9sociated with the radiation characteristics of directional ae_teb ,as, of ... more Certain phenome r ^ c 9sociated with the radiation characteristics of directional ae_teb ,as, of particular practical importance in communications engineering, are carefully defined and dealt with in detail. In tie measurement of the radiation c4h.aracte-ris'_tc: , only the coax)'.a"_ system ( 6 p -0-coaxial ca;^le ) is used, as this gives v. tfte smallest error, and in the measurement of t,'Ie casrection?l diagr'az:-: oni'S, the normalidiagram, is LaKen, as the.ormai:-zed rep re sentati,-is generally val-,English translation11 pages. 0r1g. art, has f or: Ides, i to and 7 figures.
Contemporary Biostatistics with Biopharmaceutical Applications
The vector autoregressive (VAR) and vector autoregressive moving average (VARMA) models have been... more The vector autoregressive (VAR) and vector autoregressive moving average (VARMA) models have been widely used to model multivariate time series, because of their capability to represent the dynamic relationships among variables in a system and their usefulness in forecasting unknown future values. However, when the dimension is very high, the number of parameters often exceed the number of available observations, and it is impossible to estimate the parameters. A suitable solution is clearly needed. After introducing some existing methods, we will suggest the use of contemporal aggregation as a dimension reduction method, which is very natural and simple to use. We will compare our proposed method with other existing methods in terms of forecast accuracy through both simulations and empirical examples. The presentation is based on the invited talk at the 2017 ICSA Applied Statistics Symposium in Chicago.
Abstract We consider the impacts of spatial aggregation on the model parameters and forecasts of ... more Abstract We consider the impacts of spatial aggregation on the model parameters and forecasts of the space-time autoregressive moving-average (STARMA) model. In particular, we focus on poolability, the equality of mean squared forecast error of the aggregate variable from both the non-aggregate and aggregate models, where the same model order is assumed because a model order is often unchanged under spatial aggregation, which is different from temporal aggregation. For VARMA models, there exists conditions for poolability with known parameters and a test for poolability when parameters are not known. However, this test does not apply to STARMA models due to the restricted form of their parameter matrices. In focusing on the STARMA model, we show how the aggregate model parameters are functions of the non-aggregate model parameters under poolability. In addition, we develop three poolability tests that apply to any STARMA model. We demonstrate these tests through an empirical example involving urban crime data.
Questions concerning the mechanical properties and the mechanical testing of materials come up of... more Questions concerning the mechanical properties and the mechanical testing of materials come up often in conservation practice. However, the engineering concepts of mechanical properties do not generally appear in conservation training curricula, where chemistry, and to some extent, physics, dominate the training in the natural sciences. Over the past decade, the RCE has developed a one to two day workshop on the subject as part of the basic science curricula in two conservationtraining programs. It provides conservation students with the background to deal with basic issues of the strength of materials and adhesives in their work. The workshop is based on two concepts: 1) teaching the “foreign” technical language of mechanical properties and relating that to everyday laymen’s terms, and 2) having students perform simple mechanical tests which can eventually be used in the conservation studio, without the need for complex and expensive equipment.
ABSTRACT Vibrations due to heavy construction work continue to be a major concern for museums. Al... more ABSTRACT Vibrations due to heavy construction work continue to be a major concern for museums. Although there has been an increase in research on the effect of vibrations on objects of cultural heritage in recent years, selecting measures to protect collections and remain open during construction work continues to be difficult because of a lack of data on what objects can actually withstand, the complexity of vibration loads, and the uniqueness of each situation. The major renovation of the Central Library in Liverpool, UK, which shared walls with the World Museum and Walker Art Gallery, both of which belong within National Museums Liverpool, showed how museums and other institutions can successfully deal with such situations. An integral approach was taken, beginning with an extensive risk analysis to determine which objects could remain on display, which needed extra protection and regular condition monitoring, and which had to be removed. The museums then negotiated a vibration protocol and action plan with the contractors, including continuous monitoring, and trigger levels requiring consultation or work stoppage. Vibration data were also stored and used for later analysis. This integral approach was successful in protecting the collections on exhibition, with only two incidents of reported damage directly related to vibrations. A combination of museum staff experience, excellent communications with the contractors, and some flexibility in defining vibration limits provided a successful recipe for both museums. The analysis of the vibration data using the basic engineering concept of the Palmgren-Miner rule, supports a more flexible approach to setting vibration limits based on recently published guidelines.
To investigate the role of indocyanine green (ICG) lymphangiography in the reduction of drainage ... more To investigate the role of indocyanine green (ICG) lymphangiography in the reduction of drainage after neck dissection. Patients with oral cavity squamous cell carcinoma were randomized into Group A (study group) and Group B (control). In the study group, upon the completion of neck dissection, a total of 2.5 mg of ICG was injected submucosally at the four quadrants around the tumour. Another 2.5 mg of ICG was injected subdermally in the groin bilaterally. The neck was screened using Near Infrared fluorescence. The presence of lymphatic leakage was noted and plicated with silk stitches. The total drainage volume of post-operative day 1, day 2 and the total accumulated volume until drain removal was measured. Twenty-two patients (Group A, n = 12; Group B, n = 10) were recruited. All patients in Group A had at least one site of lymphatic leakage identified. One patient in Group B developed chylous fistula and was excluded from analysis. The mean total drain output for day 1 and 2 afte...
The purpose of this study was to assess the predictability of the American Joint Committee on Can... more The purpose of this study was to assess the predictability of the American Joint Committee on Cancer (AJCC) staging system on patients with stage II recurrent nasopharyngeal carcinoma (NPC). We conducted a retrospective review of the surgical outcome for patients with recurrent NPC and retropharyngeal lymph node (RLN) metastasis (group I), recurrent NPC and parapharyngeal space (PPS) invasion (group II), and recurrent NPC and internal carotid artery (ICA) encasement (group III). Between 1990 and 2013, 145 patients received an operation for stage II recurrent NPC (group I, n = 62; group II, n = 65; and group III, n = 18). The rate of local tumor recurrence was significantly higher in groups II and III. The rate of systemic metastasis was significantly higher in group III (16.7%). Accordingly, the 5-year overall survival was significantly worse for patients in group III (group I: 81.2%; group II: 68.4%; and group III: 48.5%). The significantly worse prognosis of recurrent NPC encasing...
Prospective, observational study to assess the efficacy of salvage nasopharyngectomy for recurren... more Prospective, observational study to assess the efficacy of salvage nasopharyngectomy for recurrent nasopharyngeal carcinoma (NPC) via the endoscopic endonasal approach using a three-dimensional (3D) high-definition endoscopic system. Between 2016 and 2017, 30 patients with recurrent NPC were recruited. Patient demographics, tumor characteristics, and perioperative data were recorded. Instrument ergonomics and perceived advantages were assessed by the operating, assisting, and observing surgeons. The majority (70%) of patients received radiotherapy alone as the initial treatment for NPC, and tumor recurred after a mean interval of 16.8 months. The tumor (T) classifications of the recurrent (R) tumors were: RT1: 46.7%; RT2: 33.3%; and RT3: 20.0%. The mean operative time was 293.3 minutes, and no conversion to open approach was necessary. Internal carotid artery dissection was required in nine patients, and the resection and repair of dura was required in six patients. The most common ...
To report on the feasibility of total laryngopharyngectomy and free jejunal flap transfer for pat... more To report on the feasibility of total laryngopharyngectomy and free jejunal flap transfer for patient with hypopharyngeal cancer via the transoral robotic surgery (TORS) approach. A patient with hypopharyngeal cancer involving the post-cricoid region is used for demonstration of the TORS total laryngopharyngectomy and free jejunal flap reconstruction. The procedure starts with a cruciate incision for terminal tracheostomy. The trachea and cervical esophagus is exposed and transected, making sure that the resection margins are adequate. This is followed by the transoral dissection using the robotic surgical system. The laryngopharyngectomy specimen is delivered and the free jejunal flap is replaced transorally. Jejuno-oesophageal suturing and the microvascular anastomosis are performed through the tracheostomy wound. The remaining pharyngo-jejunal anastomosis is performed transorally via the TORS approach. TORS total laryngopharyngectomy and free jejunal flap reconstruction is feasib...
The essay addresses the question "What is Genealogy?" through a consideration of the value of tra... more The essay addresses the question "What is Genealogy?" through a consideration of the value of traditional genealogical narratives of families for the Chinese state and society, and the implications of their absence for those caught up in the 19th century diaspora to America. Using genealogy as a method of critical inquiry, however, enables scholars to begin studying the significance of this phenomenon in the lives of Chinese immigrants and the centrality of family in safeguarding their legacy. It does this through an examination of the lives of two Chinese community leaders in Denver's Chinatown. It concludes with a call for a horizontal genealogical study of community leaders in order to have a better understanding of who they were and the role they played in Chinese America.
Programmed cell death protein 4 (PDCD4) is a novel tumor suppressor protein involved in programme... more Programmed cell death protein 4 (PDCD4) is a novel tumor suppressor protein involved in programmed cell death. Its association with cancer progression has been observed in multiple tumor models, but evidence supporting its association with solid tumors in humans remains controversial. This study aimed to determine the clinical significance and prognostic value of PDCD4 in solid tumors. A systematic literature review was performed to retrieve publications with available clinical information and survival data. The eligibility of the selected articles was based on the criteria of the Dutch Cochrane Centre proposed by the Meta-analysis Of Observational Studies in Epidemiology group. Pooled odds ratios (ORs), hazard ratios (HRs), and 95% confidence intervals (CIs) for survival analysis were calculated. Publication bias was examined by Begg's and Egger's tests. Clinical data of 2227 cancer patients with solid tumors from 23 studies were evaluated. PDCD4 expression was significantl...
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