27 results on '"Sam Lam"'
Search Results
2. 271 Development of OR2805, an anti-CD163 antibody derived from an elite responder to checkpoint inhibitor therapy that relieves immunosuppression caused by M2c macrophages
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Peter Probst, Huyen Dinh, Sam Lam, Valerie Wall, Darbie Whitman, Tom Graddis, Myriam Bouchlaka, Randi Simmons, Meghan Zuck, Ray Fox, and Kamal Puri
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Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Published
- 2021
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3. 276 Discovery and preclinical characterization of anti-LILRB2 antibodies that rescue T cells from macrophage-mediated immune suppression
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Lauren Loh, Peter Probst, Huyen Dinh, Sam Lam, Valerie Wall, Francisco Zapata, Ramya Chandrasekaran, Texia Loh, Tom Graddis, Myriam Bouchlaka, Meghan Zuck, and Kamal Puri
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Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Published
- 2021
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4. Syllable based DNN-HMM Cantonese Speech to Text System.
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Timothy Wong, Claire Li, Sam Lam, Billy Chiu, Qin Lu 0001, Minglei Li 0001, Dan Xiong, Roy Shing Yu, and Vincent T. Y. Ng
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- 2024
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5. Towards safe and collaborative aerodrome operations: Assessing shared situational awareness for adverse weather detection with EEG-enabled Bayesian neural networks.
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Cho Yin Yiu, Kam K. H. Ng, Xinyu Li, Xiaoge Zhang, Qinbiao Li, Hok Sam Lam, and Man Ho Chong
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- 2022
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6. Syllable based DNN-HMM Cantonese Speech to Text System.
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Timothy Wong, Claire Li, Sam Lam, Billy Chiu, Qin Lu 0001, Minglei Li 0001, Dan Xiong, Roy Shing Yu, and Vincent T. Y. Ng
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- 2016
7. Design and Implementation of an Automated System for Assessment of Computer Programming Assignments.
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Marian Choy, Sam Lam, Chung Keung Poon, Fu Lee Wang, Yuen-Tak Yu, and Leo Yuen
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- 2007
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8. Letrozole treatment alters hippocampal gene expression in common marmosets (Callithrix jacchus)
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Mélise, Edwards, Sam, Lam, Ravi, Ranjan, Mariana, Pereira, Courtney, Babbitt, and Agnès, Lacreuse
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Behavioral Neuroscience ,Endocrinology ,Endocrine and Autonomic Systems - Abstract
Aromatase inhibitors (AIs) are a class of drugs commonly given to patients with estrogen receptor (ER)-dependent breast cancers to reduce estrogenic stimulation. However, AIs like Letrozole are associated with negative side effects such as cognitive deficits, sleep disturbances and hot flashes. We have previously shown that these negative effects can be recapitulated in common marmosets (Callithrix jacchus) treated with Letrozole (20 μg daily) for 4 weeks and that marmosets treated with Letrozole show increased levels of estradiol in the hippocampus (Gervais et al., 2019). In order to better understand the mechanisms through which AIs affect cognitive function and increase steroid levels in the hippocampus, we used bulk, paired-end RNA-sequencing to examine differentially expressed genes among Letrozole-treated (LET; n = 8) and vehicle-treated (VEH; n = 8) male and female animals. Gene ontology results show significant reduction across hundreds of categories, some of the most significant being inflammatory response, stress response, MHC Class II protein complex binding, T-cell activation, carbohydrate binding and signaling receptor binding in LET animals. GSEA results indicate that LET females, but not LET males, show enrichment for hormonal gene sets. Based on the transcriptional changes observed, we conclude that AIs may differentially affect the sexes in part due to processes mediated by the CYP-450 superfamily. Ongoing studies will further investigate the longitudinal effects of AIs on behavior and whether AIs increase the risk of stress-induced neurodegeneration.
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- 2023
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9. 271 Development of OR2805, an anti-CD163 antibody derived from an elite responder to checkpoint inhibitor therapy that relieves immunosuppression caused by M2c macrophages
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Tom Graddis, Valerie Wall, Meghan Zuck, Ray Fox, Kamal D. Puri, Myriam Bouchlaka, Darbie Whitman, Randi M Simmons, Peter Probst, Huyen Dinh, and Sam Lam
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Pharmacology ,Cancer Research ,Tumor microenvironment ,biology ,business.industry ,medicine.medical_treatment ,T cell ,Immunology ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,Pembrolizumab ,Cytokine ,medicine.anatomical_structure ,Immune system ,Oncology ,Humanized mouse ,medicine ,Cancer research ,biology.protein ,Molecular Medicine ,Immunology and Allergy ,Antibody ,business ,CD8 ,RC254-282 - Abstract
BackgroundOR2805 antibody was discovered using B cells derived from an elite responder to checkpoint inhibitor (CPI) therapy. It is a fully human IgG1 antibody that binds to CD163, an immune-suppressive receptor highly expressed on tumor associated macrophages (TAMs). High numbers of CD163-expressing TAMs generally predict an unfavorable prognosis in solid tumors. These CD163-expressing TAMs contribute to an immune-suppressive tumor microenvironment and inhibit an anti-tumor T-cell response by engaging immune checkpoints and secreting immune-suppressive cytokines. Relieving the immune suppression of CD163-expressing TAMs to improve anti-tumor T-cell responses is a rational therapeutic strategy as monotherapy and in combination with CPI therapy.MethodsCocultures of immunosuppressive primary human polarized M2c macrophages with autologous CD8+ T cells or phytohemagglutinin (PHA)-T cell blasts (exhausted T cells) were used to interrogate OR2805-dependent immunomodulatory responses as single agent and in combination with pembrolizumab, an anti-PD1 antibody. The anti-tumor activity of OR2805 was evaluated in humanized mouse models. Safety and pharmacokinetics (PK) profile of OR2805 was evaluated in cynomolgus monkeys and human whole blood for cytokine release assessment.ResultsIn coculture assays, OR2805-treatment relieved the suppressive effect of M2c macrophages as demonstrated by increased T-cell proliferation and the release of IFN-γ and perforin. OR2805 restored the IFN-γ production of exhausted T cells and showed a synergistic effect on cocultures treated in combination with pembrolizumab. OR2805-treatment demonstrated significant anti-tumor activity in lung cancer xenograft models in humanized NSG-SGM3 mice. In cynomolgus monkeys, OR2805 demonstrated a typical IgG1 PK profile and good serum exposure. Furthermore, OR2805 did not trigger the release of IL-1β, IL-2, IL-4, IL-6, IL-10, IFN-γ, or TNF-α cytokines in whole blood from either healthy donors or NSCLC patients.ConclusionsOR2805 reduced M2c-mediated immunosuppression and enhanced T cell effector functions. OR2805-treatment resulted in significant anti-tumor activity in lung cancer xenograft models in humanized mice. The pharmacology, PK, and toxicokinetic data support further development of OR2805 as an anti-cancer therapy, both as a monotherapy and in combination with CPI therapy.
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- 2021
10. 262 Preclinical characterization of humanized anti-siglec-15 antibodies that rescue T cells from macrophage-mediated immune suppression
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Valerie Wall, Peter Probst, Sam Lam, Darbie Whitman, Francisco Zapata, Lauren Loh, Huyen Dinh, Myriam Bouchlaka, Ramya Chandrasekaran, Tom Graddis, and Texia Loh
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Pharmacology ,Cancer Research ,biology ,Chemistry ,Immunology ,SIGLEC ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,respiratory system ,Immune system ,Oncology ,biology.protein ,Molecular Medicine ,Immunology and Allergy ,Macrophage ,Antibody ,RC254-282 - Abstract
BackgroundSiglec-15 is an immunosuppressive sialic acid-binding Ig-like lectin expressed by myeloid cells, tumor associated macrophages (TAMs), and some human tumors. Interactions between Siglec-15 on TAMs and sialoglycans found on cancer cells contribute to the immunosuppressive tumor microenvironment. Furthermore, Siglec-15 expressed by TAMs inhibits anti-tumor immune responses by engaging unknown immune checkpoint(s) on T cells. Notably, the mutually exclusive expression of Siglec-15 and the checkpoint ligand PD-L1 in the tumor tissue emphasizes Siglec-15 as an attractive target for combination immunotherapy. Anti-Siglec-15 antibody is currently being evaluated in clinical trials for the treatment of cancer.MethodsAnti-Siglec-15 antibodies were cloned from B cells derived from rabbits immunized with human Siglec-15 protein. The antibodies were evaluated for binding to human and cynomolgus Siglec-15 by enzyme-linked immunosorbent assay (ELISA). Top clones were selected based on activity in a panel of functional and phenotypic assays using primary human macrophages and T cells and were subsequently fully humanized. The humanized anti-Siglec-15 IgG1 antibodies were screened for binding to human and cynomolgus Siglec-15 by ELISA, binding to cells expressing Siglec-15, and ability to rescue T cell functional activity (proliferation and IFN-γ) from M2c-mediated immune suppression in vitro. The pharmacokinetics of lead humanized Siglec-15 IgG1 antibodies and their anti-tumor activity were evaluated in humanized mouse models.ResultsWe have identified a panel of fully humanized anti-Siglec-15 antibodies that bind to recombinant human and cynomolgus Siglec-15 proteins, to Siglec-15-expressing cell lines and immunosuppressive M2c macrophages without appreciable binding to other Siglec family members. Lead antibodies were identified using functional screens modeling Siglec-15-mediated immune suppression by M2c macrophages. These antibodies restored T cell immune responses in two different M2c/CD8 T cell coculture assays. In the first model, lead antibodies rescued the proliferative and IFN-γ responses of anti-CD3-activated human T cells from the inhibitory activity of M2c macrophages. In the second model, these antibodies restored the ability of exhausted CD8 T cells to secrete IFN-γ in the presence of M2c macrophages. Lead antibodies demonstrated a half-life of 6–11 days in humanized FcRn mice, and tumor growth inhibition in humanized NSG-SGM3 mice.ConclusionsWe have identified novel humanized anti-Siglec-15 antibodies that restore effector function of activated and exhausted T cells from M2c-mediated immune suppression, with excellent half-life and anti-tumor activity in humanized mouse models. These data provide a strong rationale for further development of these antibodies for anti-cancer immunotherapy.
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- 2021
11. Development of a Point-of-Care Ultrasound Educational Milestone for Pediatric Emergency Medicine Fellows
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Deborah Hsu, Sam Lam, Jennifer R. Marin, David P. Way, Delia L. Gold, Marla C. Levine, and Allan Evan Shefrin
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Pediatric emergency medicine ,business.industry ,Point of care ultrasound ,Pediatrics, Perinatology and Child Health ,Milestone (project management) ,medicine ,Medical emergency ,medicine.disease ,business - Published
- 2021
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12. Abstract 1719: OR2805, an anti-CD163 antibody derived from an elite responder to checkpoint inhibitor therapy relieves immunosuppression caused by tumor associated macrophages
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Valerie Wall, Randi M Simmons, Meghan Zuck, Sam Lam, Myriam Bouchlaka, Peter Probst, Kamal D. Puri, Darbie Whitman, Raymond D. Fox, and Tom Graddis
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Cancer Research ,Tumor microenvironment ,Myeloid ,biology ,business.industry ,medicine.medical_treatment ,Immunosuppression ,Haematopoiesis ,Immune system ,medicine.anatomical_structure ,Oncology ,Humanized mouse ,biology.protein ,Cancer research ,Medicine ,Antibody ,business ,CD8 - Abstract
Background: OR2805 is a fully human IgG1 antibody that binds to CD163, an immune-suppressive receptor highly expressed on tumor associated macrophages (TAMs). High numbers of CD163-expressing TAMs generally predict an unfavorable prognosis in solid tumors. CD163-expressing TAMs contribute to an immune-suppressive tumor microenvironment (TME) and inhibit an anti-tumor T-cell response by engaging immune checkpoints, producing immune-suppressive cytokines, and promoting T-cell skewing towards a pro-cancer Th2 phenotype. Relieving the immune suppression of CD163-expressing TAMs in the TME to improve T-cell-mediated responses is a rational adjunct to immune checkpoint inhibitor (CPI) therapy. Methods: OR2805 was discovered using OncoResponse's discovery platform by cell-based functional and phenotypic assays. B cells derived from CPI elite responders were cultured at clonal density, and IgG antibodies in supernatants were evaluated for binding to myeloid-derived suppressor cells. Variable-regions from positive hits were sequenced, cloned, and expressed as recombinant IgG1. OR2805 was identified as one of the top hits that relieved myeloid cell-mediated immune suppression. Co-cultures of immunosuppressive primary human M2 macrophages and autologous T cells were used to interrogate OR2805-dependent immunomodulatory responses in vitro. The anti-tumor activity of OR2805 in vivo was evaluated in a humanized mouse model. Results: OR2805 binds to CD163 expressed on TAMs and M2-like macrophages. OR2805 does not bind to other hematopoietic cells nor to a panel of human primary non-immune cells. OR2805 treatment reduces expression of cell-surface markers associated with tumor-promoting M2c-like macrophages. In co-culture assays, OR2805 relieves the suppressive effect of M2 macrophages and results in increased T-cell activation and proliferation, upregulation of T-cell activation markers, and enhanced T-cell-mediated tumor cell killing. Administration of OR2805 in humanized NSG-SGM3 mouse tumor models resulted in approximately 55% and 75% reduction in A549 tumor growth and NCI-H1975 tumor growth, respectively. In this model, OR2805 treatment significantly increased the proportions of human CD8+ T cells and human CD11b+ myeloid cells, as well as significantly enhanced expression of activation markers by human CD8+ T cells. Conclusions: OR2805 reduces M2 macrophage-mediated immunosuppression and enhances anti-tumor immune responses. OR2805 treatment induces anti-tumor activity in lung cancer xenograft models in humanized mice. These data support further development of OR2805 as an anti-cancer therapy, both as a monotherapy and an addition to current CPI therapy. Citation Format: Peter Probst, Randi Simmons, Valerie Wall, Meghan Zuck, Myriam Bouchlaka, Sam Lam, Raymond Fox, Darbie Whitman, Tom Graddis, Kamal D. Puri. OR2805, an anti-CD163 antibody derived from an elite responder to checkpoint inhibitor therapy relieves immunosuppression caused by tumor associated macrophages [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1719.
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- 2021
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13. Polymorphisms of EHF-ELF5 genomic region and its association with pediatric asthma in the Taiwanese population
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Jiu Yao Wang, Frada Wei Sam Lam, Lawrence Shih-Hsin Wu, and Shyh Dar Shyur
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0301 basic medicine ,Male ,Microbiology (medical) ,medicine.medical_specialty ,Candidate gene ,Genotype ,Population ,Taiwan ,Single-nucleotide polymorphism ,Polymorphism, Single Nucleotide ,03 medical and health sciences ,0302 clinical medicine ,Gene Frequency ,Internal medicine ,Immunology and Microbiology(all) ,medicine ,SNP ,Humans ,genetic polymorphism ,Immunology and Allergy ,Genetic Predisposition to Disease ,education ,Child ,Genetic Association Studies ,Genetic association ,Asthma ,Genetics ,education.field_of_study ,General Immunology and Microbiology ,Proto-Oncogene Proteins c-ets ,business.industry ,General Medicine ,Odds ratio ,medicine.disease ,ELF5 ,DNA-Binding Proteins ,030104 developmental biology ,Infectious Diseases ,030228 respiratory system ,Child, Preschool ,Female ,business ,EHF ,Transcription Factors ,pediatric asthma - Abstract
Background The EHF and ELF5 genes, located on chromosome 11p and linked to asthma phenotypes, are high-potential candidate genes conferring asthma susceptibility. The purpose of this study was to investigate the genetic association among single nucleotide polymorphisms (SNPs) of EHF and ELF5 , and their relationship with asthma in the Taiwanese population. Methods We selected and performed genotyping on 16 SNPs that encompass the genomic region of EHF and ELF5 in Taiwanese children with or without asthma. A total of 1983 children, 523 in the test group and 619 and 842 in two validation groups, were recruited for this study. Results The SNP rs3910901, located in the 5′ upstream region of ELF5 , was found to have a weak association ( p = 0.043) with asthma in the odds ratio analysis. The genotype distribution was similar in all comparison groups, but the CC genotype was more frequent in asthma patients. Logistic regression adjusted allergy comorbidity showed obviously diluted association. Conclusion The results indicated that SNP rs3910901 may have a minor impact on pediatric asthma in the Taiwanese population.
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- 2016
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14. Su1663 EARLY WITHDRAWAL OF STEROIDS IN AUTOIMMUNE HEPATITIS MAY BE FEASIBLE WITH LOW RATES OF RELAPSE
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Alan Bonder, Daniela Goyes, Jennifer Lee, Lauren M. Yang, Vilas Patwardhan, Sam Lam, and Lauren D. Gilbert
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Hepatology ,business.industry ,Immunology ,Gastroenterology ,Medicine ,Autoimmune hepatitis ,business ,medicine.disease - Published
- 2020
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15. Geology defines microbiome structure and composition in nunataks and valleys of the Sør Rondane Mountains, East Antarctica
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Valentina Savaglia, Sam Lambrechts, Bjorn Tytgat, Quinten Vanhellemont, Josef Elster, Anne Willems, Annick Wilmotte, Elie Verleyen, and Wim Vyverman
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microbial ecology ,Antarctica ,bedrock ,rRNA ,bacteria ,eukaryotes ,Microbiology ,QR1-502 - Abstract
Understanding the relation between terrestrial microorganisms and edaphic factors in the Antarctic can provide insights into their potential response to environmental changes. Here we examined the composition of bacterial and micro-eukaryotic communities using amplicon sequencing of rRNA genes in 105 soil samples from the Sør Rondane Mountains (East Antarctica), differing in bedrock or substrate type and associated physicochemical conditions. Although the two most widespread taxa (Acidobacteriota and Chlorophyta) were relatively abundant in each sample, multivariate analysis and co-occurrence networks revealed pronounced differences in community structure depending on substrate type. In moraine substrates, Actinomycetota and Cercozoa were the most abundant bacterial and eukaryotic phyla, whereas on gneiss, granite and marble substrates, Cyanobacteriota and Metazoa were the dominant bacterial and eukaryotic taxa. However, at lower taxonomic level, a distinct differentiation was observed within the Cyanobacteriota phylum depending on substrate type, with granite being dominated by the Nostocaceae family and marble by the Chroococcidiopsaceae family. Surprisingly, metazoans were relatively abundant according to the 18S rRNA dataset, even in samples from the most arid sites, such as moraines in Austkampane and Widerøefjellet (“Dry Valley”). Overall, our study shows that different substrate types support distinct microbial communities, and that mineral soil diversity is a major determinant of terrestrial microbial diversity in inland Antarctic nunataks and valleys.
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- 2024
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16. 3He spin-echo scattering indicates hindered diffusion of isolated water molecules on graphene-covered Ir(111)
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Signe Kyrkjebø, Andrew Cassidy, Sam Lambrick, Andrew Jardine, Bodil Holst, and Liv Hornekær
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surface dynamics ,surface diffusion ,wettability ,helium-3 spin-echo scattering ,graphene ,iridium ,Chemistry ,QD1-999 - Abstract
The dynamics of water diffusion on carbon surfaces are of interest in fields as diverse as furthering the use of graphene as an industrial-coating technology and understanding the catalytic role of carbon-based dust grains in the interstellar medium. The early stages of water–ice growth and the mobility of water adsorbates are inherently dependent on the microscopic mechanisms that facilitate water diffusion. Here, we use 3He spin-echo quasi-inelastic scattering to probe the microscopic mechanisms responsible for the diffusion of isolated water molecules on graphene-covered and bare Ir(111). The scattering of He atoms provides a non-invasive and highly surface-sensitive means to measure the rate at which absorbates move around on a substrate at very low coverage. Our results provide an approximate upper limit on the diffusion coefficient for water molecules on GrIr(111) of
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- 2023
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17. Analysis of Students’ Feedback to Improve Course Programme ANQ Congress 2014 Singapore
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Francis Chua and Sam Lam
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Medical education ,Service (systems architecture) ,business.industry ,Media studies ,Root cause ,Employability ,Outcome (game theory) ,Brainstorming ,Software deployment ,ComputingMilieux_COMPUTERSANDEDUCATION ,Medicine ,Seven Basic Tools of Quality ,Root cause analysis ,business - Abstract
Over the years, there is an increasing trend of using quality tools and techniques in service sectors to address customer feedback. Deployment of such quality tools in the education sector is relatively new. Coleman College in Singapore faced feedback from the student community that the Advanced Diploma in Accounting course is too focused on academic learning. This issue was brought up to the Academic Board for further discussion. There were a couple of suggestions and the team embarked on a root cause analysis to analyse the feedback. One root cause identified is the lack of skill-based learning in the current course. The team then brainstorm to incorporate MYOB, the accounting software, into the course programme as a new module. In addition to adding more practical aspects to the course, this implementation also benefits the students by improving their employability. A post-implementation feedback was gathered again to ascertain the effectiveness of the learning outcome. The feedback was positive and the implementation is successful.
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- 2017
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18. Review of the 5th Brazilian Meeting of Hair Restoration Surgery May 21-24, 2014 • São Paulo, Brazil
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Sam Lam, Arthur Tykocinski, and Henrique N. Radwanski
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medicine.medical_specialty ,business.industry ,General surgery ,medicine ,business - Published
- 2014
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19. Getting savvy about orchids
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Sam, Lam Peng
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Business, international - Abstract
ORCHID cultivation used to be a very popular hobby but has now graduated into a profitable cut flower industry in Malaysia as well as in Southeast Asia. The continuous breeding [...]
- Published
- 2000
20. GHOST Commissioning Science Results: Identifying a New Chemically Peculiar Star in Reticulum II
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Christian R. Hayes, Kim A. Venn, Fletcher Waller, Jaclyn Jensen, Alan W. McConnachie, John Pazder, Federico Sestito, André Anthony, Gabriella Baker, John Bassett, Joao Bento, Trystyn Berg, Gregory Burley, Jurek Brzeski, Scott Case, Edward Chapin, Timothy Chin, Eric Chisholm, Vladimir Churilov, Adam Densmore, Ruben Diaz, Jennifer Dunn, Michael Edgar, Tony Farrell, Veronica Firpo, Joeleff Fitzsimmons, Juan Font-Serra, Javier Fuentes, Colin Ganton, Manuel Gomez-Jimenez, Tim Hardy, David Henderson, Alexis Hill, Brian Hoff, Michael Ireland, Venu Kalari, Neal Kelly, Urs Klauser, Yuriy Kondrat, Kathleen Labrie, Sam Lambert, Lance Luvaul, Jon Lawrence, Jordan Lothrop, G. Scott Macdonald, Slavko Mali, Steve Margheim, Richard McDermid, Helen McGregor, Bryan Miller, Felipe Miranda, Rolf Muller, Jon Nielsen, Ryan Norbury, Oliver Oberdorf, Naveen Pai, Gabriel Perez, Pablo Prado, Ian Price, Carlos Quiroz, Vladimir Reshetov, Gordon Robertson, Roque Ruiz-Carmona, Ricardo Salinas, Kim M. Sebo, Andrew Sheinis, Matthew Shetrone, Keith Shortridge, Katherine Silversides, Karleyne Silva, Chris Simpson, Greg Smith, Kei Szeto, Julia Tims, Eduardo Toro, Cristian Urrutia, Sudharshan Venkatesan, Lewis Waller, Ivan Wevers, Ramunas Wierzbicki, Marc White, Peter Young, and Ross Zhelem
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Dwarf galaxies ,Chemically peculiar stars ,Chemical abundances ,High resolution spectroscopy ,Observational astronomy ,Astrophysics ,QB460-466 - Abstract
The Gemini High-resolution Optical SpecTrograph (GHOST) is the newest high-resolution spectrograph to be developed for a large-aperture telescope, recently deployed and commissioned at the Gemini-South telescope. In this paper, we present the first science results from the GHOST spectrograph taking during its commissioning runs. We have observed the bright metal-poor benchmark star HD 122563, along with two stars in the ultrafaint dwarf galaxy Reticulum II (Ret ii ), one of which was previously identified as a candidate member, but did not have a previous detailed chemical abundance analysis. We find that this candidate (GDR3 0928) to be a bona fide member of Ret ii , and from a spectral synthesis analysis it is also revealed to be a CEMP- r star, with significant enhancements in several light elements (C, N, O, Na, Mg, and Si), in addition to featuring an r -process enhancement like many other Ret ii stars. The light-element enhancements in this star resemble the abundance patterns seen in the CEMP-no stars of other ultrafaint dwarf galaxies, and are thought to have been produced by an independent source from the r -process. These unusual abundance patterns are thought to be produced by faint supernovae, which may be produced by some of the earliest generations of stars.
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- 2023
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21. The Effects Stretching on H-reflex and Related Parameters
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Sam Lam, Li Li, Joke Kokkonen, and Arnold G. Nelson
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Nuclear magnetic resonance ,Chemistry ,Physical Therapy, Sports Therapy and Rehabilitation ,Orthopedics and Sports Medicine ,H-reflex - Published
- 2011
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22. Bromeliads for low light areas
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Sam, Lam Peng
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General interest - Abstract
BROMELIADS are plants which can answer most of our decoration needs. They can grow even in semi-shade, and will reward you with lovely and colourful blooms when mature. These monocotyledonous [...]
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- 2000
23. Tree beauties for cool shade
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Sam, Lam Peng
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General interest - Abstract
THE family Leguminosae includes some of the most glorious flowering trees. Many of them are tropical or subtropical. A number of countries have chosen a showy legume as their national [...]
- Published
- 2000
24. Wild and cultivated orchids
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Sam, Lam Peng
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General interest - Abstract
THE Dendrobium Orchid A COMMON orchid and one of the easiest to grow in our gardens is the Dendrobium. It is the second largest genus in the orchid family, comprising [...]
- Published
- 2000
25. The colourful and hardy Vandas
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Sam, Lam Peng
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General interest - Abstract
FOR the past two weeks, we have been looking at a few orchid species which stood out from the other colourful blooms - the Oncidiums or 'dancing ladies' and the [...]
- Published
- 2000
26. Active bialkali photocathodes on free-standing graphene substrates
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Hisato Yamaguchi, Fangze Liu, Jeffrey DeFazio, Claudia W. Narvaez Villarrubia, Daniel Finkenstadt, Andrew Shabaev, Kevin L. Jensen, Vitaly Pavlenko, Michael Mehl, Sam Lambrakos, Gautam Gupta, Aditya D. Mohite, and Nathan A. Moody
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Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Chemistry ,QD1-999 - Abstract
Graphene in accelerator technology: A new material for enhanced photocathode performance and lifetime Graphene has shown potential to unlock new capabilities of electron sources and other aspects of accelerator technology. This report focuses on integrating graphene with high performance photocathodes with the goal of extending lifetime by thousands of hours. Scientists at Los Alamos National Laboratory, USA, and colleagues succeeded in growth of chemically susceptible photocathodes on free-standing graphene substrates while maintaining state-of-the-art performance. Successful growth on graphene is a critical step toward a material-centric approach to photocathode design: enhancing lifetime without compromising efficiency or other performance metrics. Graphene, an atomically thin sheet of carbon, is an emerging material that has inspired new cathode design capabilities, including heterostructuring, resonant tunneling, and impermeable gas barriers. Conventional photocathode materials have no performance regimes. The next step is complete graphene encapsulation of photocathode films and demonstration of lifetime enhancement in the operating environment of accelerator facilities.
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- 2017
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27. Uncovering the Uncultivated Majority in Antarctic Soils: Toward a Synergistic Approach
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Sam Lambrechts, Anne Willems, and Guillaume Tahon
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Antarctica ,uncultivated majority ,cultivation ,terrestrial ,cultivation-independent ,metagenomics ,Microbiology ,QR1-502 - Abstract
Although Antarctica was once believed to be a sterile environment, it is now clear that the microbial communities inhabiting the Antarctic continent are surprisingly diverse. Until the beginning of the new millennium, little was known about the most abundant inhabitants of the continent: prokaryotes. From then on, however, the rising use of deep sequencing techniques has led to a better understanding of the Antarctic prokaryote diversity and provided insights in the composition of prokaryotic communities in different Antarctic environments. Although these cultivation-independent approaches can produce millions of sequences, linking these data to organisms is hindered by several problems. The largest difficulty is the lack of biological information on large parts of the microbial tree of life, arising from the fact that most microbial diversity on Earth has never been characterized in laboratory cultures. These unknown prokaryotes, also known as microbial dark matter, have been dominantly detected in all major environments on our planet. Laboratory cultures provide access to the complete genome and the means to experimentally verify genomic predictions and metabolic functions and to provide evidence of horizontal gene transfer. Without such well-documented reference data, microbial dark matter will remain a major blind spot in deep sequencing studies. Here, we review our current understanding of prokaryotic communities in Antarctic ice-free soils based on cultivation-dependent and cultivation-independent approaches. We discuss advantages and disadvantages of both approaches and how these strategies may be combined synergistically to strengthen each other and allow a more profound understanding of prokaryotic life on the frozen continent.
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- 2019
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