Pub Date : 2011-11-20DOI: 10.1142/S0219607711000687
H. Dutton, F. Siperstein, G. Tiddy
Surfactants self-associate in aqueous solutions to form micelles. Less well-known is that they form a wide range of liquid crystals — through self-association. These liquid crystals often occur in consumer products where they play an essential role in product stability and function. Some products are marketed in a liquid crystalline state although they are not recognized by the consumer (or, on occasion, by the manufacturer). This review describes the formation of micelles and the various liquid crystalline phases. These include lamellar, hexagonal, cubic and gel phases which have different long range structures but are based on micelles. The key factors linking surfactant molecular structure to liquid crystal architecture have been elucidated. These are the sizes of the surfactant hydrophobic tail(s) and head groups, together with the head group charge and the presence of any additives. Examples of liquid crystals in emulsion stabilization, household cleaners, conditioners, detergent liquid and some food are described.
{"title":"PRODUCT FORMULATION WITH SURFACTANT NANOSTRUCTURES: LIQUID CRYSTALS, SOFT SOAP AND A PIECE OF CAKE","authors":"H. Dutton, F. Siperstein, G. Tiddy","doi":"10.1142/S0219607711000687","DOIUrl":"https://doi.org/10.1142/S0219607711000687","url":null,"abstract":"Surfactants self-associate in aqueous solutions to form micelles. Less well-known is that they form a wide range of liquid crystals — through self-association. These liquid crystals often occur in consumer products where they play an essential role in product stability and function. Some products are marketed in a liquid crystalline state although they are not recognized by the consumer (or, on occasion, by the manufacturer). This review describes the formation of micelles and the various liquid crystalline phases. These include lamellar, hexagonal, cubic and gel phases which have different long range structures but are based on micelles. The key factors linking surfactant molecular structure to liquid crystal architecture have been elucidated. These are the sizes of the surfactant hydrophobic tail(s) and head groups, together with the head group charge and the presence of any additives. Examples of liquid crystals in emulsion stabilization, household cleaners, conditioners, detergent liquid and some food are described.","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"62 1","pages":"65-74"},"PeriodicalIF":0.0,"publicationDate":"2011-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84812058","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1142/S0219607710000577
Loh Pui Yee, Liu Chenmin, Pua Weicheng, K. Yu, Chin Wee Shong
In this short review, we report the facile fabrication of various interesting multi-component nanostructures including arrays of core-shell nanowires, multiwall nanotubes, segmented nanowires and multilayer stacked nanodisks, using anodized alumina membrane (AAM). We demonstrate that metallic (Cu, Ni and Au) and polymeric (PPV and PPy) one-dimensional (1D) arrays can be readily prepared by electrochemical deposition into the AAM. By optimizing the experimental design and conditions, we developed techniques to produce various multi-component nanostructures such as polymer/metal or metal/metal core-shell nanowires as well as nanotubes, with reasonably good control over both the length and the shell thickness of the nanostructures. Furthermore, we extend this method to make segmented nanowires as well as multilayer stacked nanodisks. Selective functionalization of the segmented nanowires resulted in end-on or side-on adhesion of nanowires during assembly. We illustrate the possibility of utilizing these 1D arrays to present patterns with luminescent and/or magnetic properties at this length scale.
{"title":"FACILE FABRICATION OF ONE-DIMENSIONAL MULTI-COMPONENT NANOSTRUCTURES USING POROUS ANODIZED ALUMINA MEMBRANE","authors":"Loh Pui Yee, Liu Chenmin, Pua Weicheng, K. Yu, Chin Wee Shong","doi":"10.1142/S0219607710000577","DOIUrl":"https://doi.org/10.1142/S0219607710000577","url":null,"abstract":"In this short review, we report the facile fabrication of various interesting multi-component nanostructures including arrays of core-shell nanowires, multiwall nanotubes, segmented nanowires and multilayer stacked nanodisks, using anodized alumina membrane (AAM). We demonstrate that metallic (Cu, Ni and Au) and polymeric (PPV and PPy) one-dimensional (1D) arrays can be readily prepared by electrochemical deposition into the AAM. By optimizing the experimental design and conditions, we developed techniques to produce various multi-component nanostructures such as polymer/metal or metal/metal core-shell nanowires as well as nanotubes, with reasonably good control over both the length and the shell thickness of the nanostructures. Furthermore, we extend this method to make segmented nanowires as well as multilayer stacked nanodisks. Selective functionalization of the segmented nanowires resulted in end-on or side-on adhesion of nanowires during assembly. We illustrate the possibility of utilizing these 1D arrays to present patterns with luminescent and/or magnetic properties at this length scale.","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"44 1","pages":"221-234"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73557167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1142/S0219607710000620
Weihua Hu, C. M. Li
Reported was a novel amperometric immunosensor based on layer-by-layer (LbL) assembled polyethylenimine/gold nanoparticles/poly (acrylic acid) (PEI/AuNPs/PAA) multilayer. The assembly process was in situ monitored by surface plasmon resonance (SPR) technique. Anti-goat IgG as a capture antibody was covalently immobilized on the outermost PAA layer of the multilayer to construct an immunosensor. A target protein, goat IgG was electrochemically detected with alkaline phosphatase-conjugated anti-goat IgG (ALP-anti-goat IgG) as a recognition antibody. Electrochemical investigations suggest that the incorporation of AuNPs facilitates the electron transfer between the underlying electrode and the redox species in solution, and thus enhances the electrochemical signals and in turn improves the immunosensing performance. A detection limit of 100 pg mL-1 with a dynamic range of five orders of magnitude was achieved. Due to the protein-friendly environment and the protein resistance of the polyelectrolyte multilayer, the resulting immunosensor demonstrates excellent storage stability, satisfying assay specificity.
{"title":"GOLD NANOPARTICLE-INCORPORATED POLYELECTROLYTE MULTILAYER FOR SENSITIVE ELECTROCHEMICAL IMMUNOSENSING","authors":"Weihua Hu, C. M. Li","doi":"10.1142/S0219607710000620","DOIUrl":"https://doi.org/10.1142/S0219607710000620","url":null,"abstract":"Reported was a novel amperometric immunosensor based on layer-by-layer (LbL) assembled polyethylenimine/gold nanoparticles/poly (acrylic acid) (PEI/AuNPs/PAA) multilayer. The assembly process was in situ monitored by surface plasmon resonance (SPR) technique. Anti-goat IgG as a capture antibody was covalently immobilized on the outermost PAA layer of the multilayer to construct an immunosensor. A target protein, goat IgG was electrochemically detected with alkaline phosphatase-conjugated anti-goat IgG (ALP-anti-goat IgG) as a recognition antibody. Electrochemical investigations suggest that the incorporation of AuNPs facilitates the electron transfer between the underlying electrode and the redox species in solution, and thus enhances the electrochemical signals and in turn improves the immunosensing performance. A detection limit of 100 pg mL-1 with a dynamic range of five orders of magnitude was achieved. Due to the protein-friendly environment and the protein resistance of the polyelectrolyte multilayer, the resulting immunosensor demonstrates excellent storage stability, satisfying assay specificity.","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"5 1","pages":"197-205"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80144424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1142/S0219607710000607
Xiao Huang, F. Boey, Hua Zhang
Graphene, a single layer of hexagonal packed carbon atoms, has attracted increasing attention in recent years. Because of its exceptional electronic, optical, mechanical, and thermal properties, graphene has shown great promises in a wide range of applications. Graphene derivatives, e.g. graphene oxide (GO) and reduced graphene oxide (rGO) sheets, possess surface defects and oxygen functional groups, which make them ideal templates for synthesis of metal and semiconductor nanoparticles (NPs). Enhanced properties are expected in these graphene–NP composites, which arise from the synergic effect of the GO/rGO sheets and the anchored NPs. In this review, after a brief introduction on the properties and synthesis of graphene, we will discuss the fabrication methods of graphene–metal NP and graphene–semiconductor NP composites, as well as their related applications in catalysis, photovoltaic devices, supercapacitors, and so on.
{"title":"A BRIEF REVIEW ON GRAPHENE-NANOPARTICLE COMPOSITES","authors":"Xiao Huang, F. Boey, Hua Zhang","doi":"10.1142/S0219607710000607","DOIUrl":"https://doi.org/10.1142/S0219607710000607","url":null,"abstract":"Graphene, a single layer of hexagonal packed carbon atoms, has attracted increasing attention in recent years. Because of its exceptional electronic, optical, mechanical, and thermal properties, graphene has shown great promises in a wide range of applications. Graphene derivatives, e.g. graphene oxide (GO) and reduced graphene oxide (rGO) sheets, possess surface defects and oxygen functional groups, which make them ideal templates for synthesis of metal and semiconductor nanoparticles (NPs). Enhanced properties are expected in these graphene–NP composites, which arise from the synergic effect of the GO/rGO sheets and the anchored NPs. In this review, after a brief introduction on the properties and synthesis of graphene, we will discuss the fabrication methods of graphene–metal NP and graphene–semiconductor NP composites, as well as their related applications in catalysis, photovoltaic devices, supercapacitors, and so on.","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"31 1","pages":"159-166"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90220682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1142/S0219607710000619
Yih Hong Lee, P. Lakshminarayana, Cuifeng Jiang, Peiyan Yuan, Qinghua Xu
Noble metal nanoparticles exhibit strong surface plasmon resonance (SPR) and have been utilized in many chemical, biological and electronic applications. Recent advances on metal-enhanced optical properties demonstrated that the quantum yield and photo-stability of the fluorophores can be significantly enhanced when they are in the proximity of the metal surface, that will benefit many fluorescence-based applications. In this review article we first discuss the fundamental concepts of metal-enhanced optical properties and the recent achievements of metal-enhanced fluorescence of organic fluorophores and quantum dots, as well as metal-enhanced phosphorescence of organic molecules and upconversion nanoparticles that have long life times. Finally, we present recent applications of metal-enhanced optical properties in biosensing and bioassays, photodynamic therapy and optoelectronics.
{"title":"RECENT ADVANCES IN METAL-ENHANCED OPTICAL PROPERTIES","authors":"Yih Hong Lee, P. Lakshminarayana, Cuifeng Jiang, Peiyan Yuan, Qinghua Xu","doi":"10.1142/S0219607710000619","DOIUrl":"https://doi.org/10.1142/S0219607710000619","url":null,"abstract":"Noble metal nanoparticles exhibit strong surface plasmon resonance (SPR) and have been utilized in many chemical, biological and electronic applications. Recent advances on metal-enhanced optical properties demonstrated that the quantum yield and photo-stability of the fluorophores can be significantly enhanced when they are in the proximity of the metal surface, that will benefit many fluorescence-based applications. In this review article we first discuss the fundamental concepts of metal-enhanced optical properties and the recent achievements of metal-enhanced fluorescence of organic fluorophores and quantum dots, as well as metal-enhanced phosphorescence of organic molecules and upconversion nanoparticles that have long life times. Finally, we present recent applications of metal-enhanced optical properties in biosensing and bioassays, photodynamic therapy and optoelectronics.","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"45 1","pages":"167-195"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80938412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1142/S0219607710000565
Lihua Wang, Yanyan Wang, Jie-ming Zou, Bin Liu, C. Fan
Development of rapid, field-portable and cost-effective sensors with high sensitivity and selectivity is of great importance for biomedical diagnostics, food safety and environmental monitoring. Silica nanoparticles (SiNPs) have great potential in sensor application due to their biocompatibility, controllable surface modification, excellent chemical stability and high specific surface area. On the other hand, conjugated polyelectrolytes (CPEs) have been widely used in sensor design due to their efficient Forster resonance energy transfer (FRET) to dyes and unique interaction with biomolecules. In this contribution, we briefly summarize the recent development of silica-related NP-based assays that incorporate CPEs as the signal amplifier or reporter. The silica-related NPs are used for probe immobilization, target recognition and separation, while CPEs provide amplified fluorescence signals and high sensitivity. These assays have been proven efficient for the detection of DNA, proteins, and small molecules through specific biorecognition events, such as DNA hybridization, antibody–antigen recognition and target–aptamer binding.
{"title":"AMPLIFIED BIOSENSING STRATEGIES FOR THE DETECTION OF BIOLOGICALLY RELATED MOLECULES WITH SILICA NANOPARTICLES AND CONJUGATED POLYELECTROLYTES","authors":"Lihua Wang, Yanyan Wang, Jie-ming Zou, Bin Liu, C. Fan","doi":"10.1142/S0219607710000565","DOIUrl":"https://doi.org/10.1142/S0219607710000565","url":null,"abstract":"Development of rapid, field-portable and cost-effective sensors with high sensitivity and selectivity is of great importance for biomedical diagnostics, food safety and environmental monitoring. Silica nanoparticles (SiNPs) have great potential in sensor application due to their biocompatibility, controllable surface modification, excellent chemical stability and high specific surface area. On the other hand, conjugated polyelectrolytes (CPEs) have been widely used in sensor design due to their efficient Forster resonance energy transfer (FRET) to dyes and unique interaction with biomolecules. In this contribution, we briefly summarize the recent development of silica-related NP-based assays that incorporate CPEs as the signal amplifier or reporter. The silica-related NPs are used for probe immobilization, target recognition and separation, while CPEs provide amplified fluorescence signals and high sensitivity. These assays have been proven efficient for the detection of DNA, proteins, and small molecules through specific biorecognition events, such as DNA hybridization, antibody–antigen recognition and target–aptamer binding.","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"44 2 1","pages":"207-219"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83923924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1142/S0219607710000589
Yinthai Chan
Significant efforts in the field of colloidal semiconductor particles have been dedicated to the fabrication and study of hybrid metal–semiconductor nanoheterostructures, where the incorporation of the metal moiety may potentially enhance and/or expand existing applications of semiconductor nanoparticles. Many of these metal–semiconductor nanostructured constructs exhibit physical properties not found in either of their metal or semiconductor components, providing many opportunities for further investigation into interface and coupling effects between the two materials. We review some of the key research endeavors in this area, focusing mainly on the synthesis of the materials and the characterization of the various metal–semiconductor constructs, and highlighting some of the unique applications that have emerged from these efforts.
{"title":"HETEROSTRUCTURED HYBRID COLLOIDAL SEMICONDUCTOR NANOCRYSTALS","authors":"Yinthai Chan","doi":"10.1142/S0219607710000589","DOIUrl":"https://doi.org/10.1142/S0219607710000589","url":null,"abstract":"Significant efforts in the field of colloidal semiconductor particles have been dedicated to the fabrication and study of hybrid metal–semiconductor nanoheterostructures, where the incorporation of the metal moiety may potentially enhance and/or expand existing applications of semiconductor nanoparticles. Many of these metal–semiconductor nanostructured constructs exhibit physical properties not found in either of their metal or semiconductor components, providing many opportunities for further investigation into interface and coupling effects between the two materials. We review some of the key research endeavors in this area, focusing mainly on the synthesis of the materials and the characterization of the various metal–semiconductor constructs, and highlighting some of the unique applications that have emerged from these efforts.","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"39 1","pages":"235-245"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81089345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1142/S0219607710000590
Suhua Wang, Dejian Huang
In this review, we systematically analyzed the complicated interrelationship between photoluminescent quantum dots (QDs) and reactive oxygen species of biological importance. QDs, when photoexcited, generate reactive oxygen species (ROS), which are partially blamed for the cytotoxicity of QDs. On the positive side, the ability of generating ROS by QDs are exploited in photodynamic therapy using QDs alone or in combination with QD-surface bound organic sensitizers via resonance energy transfer from QDs to the organic dyes. Lastly, depending on the chemical composition and the functionalization of the QDs, ROS are known to quench or switch-on the QD photoluminescence. The selectivity and sensitivity toward specific ROS can be achieved through judicious chemical modification of QD surface coating layers by taking into account the reactivity difference among different ROS. The flexible QD surface functionalization opens up the unprecedented possibility of designer-made nanoprobes for sensing and quantifying ROS of biological importance.
{"title":"THE ROLES OF PHOTOLUMINESCENT QUANTUM DOTS IN GENERATION OR DETECTION OF REACTIVE OXYGEN SPECIES: CULPRITS OR DETECTIVES?","authors":"Suhua Wang, Dejian Huang","doi":"10.1142/S0219607710000590","DOIUrl":"https://doi.org/10.1142/S0219607710000590","url":null,"abstract":"In this review, we systematically analyzed the complicated interrelationship between photoluminescent quantum dots (QDs) and reactive oxygen species of biological importance. QDs, when photoexcited, generate reactive oxygen species (ROS), which are partially blamed for the cytotoxicity of QDs. On the positive side, the ability of generating ROS by QDs are exploited in photodynamic therapy using QDs alone or in combination with QD-surface bound organic sensitizers via resonance energy transfer from QDs to the organic dyes. Lastly, depending on the chemical composition and the functionalization of the QDs, ROS are known to quench or switch-on the QD photoluminescence. The selectivity and sensitivity toward specific ROS can be achieved through judicious chemical modification of QD surface coating layers by taking into account the reactivity difference among different ROS. The flexible QD surface functionalization opens up the unprecedented possibility of designer-made nanoprobes for sensing and quantifying ROS of biological importance.","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"197 1","pages":"149-158"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1142/S0219607710000590","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72423940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-12-01DOI: 10.1142/S0219607710000668
T. Hor
The pace of growth for research in Singapore is nothing short of spectacular. Though still in its infancy compared to the might of research giants like Finland, Norway, Israel, Japan, USA, UK and China, Singapore is rapidly moving into higher gear. This comes at a time when the research and development (R&D) of some of the world's leading nations has stalled due in part to the financial meltdown that has only recently seen signs of recovery. But as the saying goes, the best opportunities are found in times of adversity. The approach that Singapore takes is an astute one. Investment in R&D for a country with no natural resources has to be based on the next best thing — intellectual capital and its people. Developing R&D capabilities in a knowledge-based economy therefore depends first and foremost on our human capital. An integrated effort in education and research is hence crucial. The government has taken the lead in R&D investment. It has set a national target of driving the current level of 2.9% of gross domestic expenditure on research and development (GERD) to 3.5% by 2015 — a significant milestone that would put Singapore in the "premier league" of R&D nations. It is with this objective that the new national R&D budget for the next five years will be increased by more than 20% to S$16.1 billion. This increase is justified on the basis of pushing a research agenda that is driven by innovation with an economic mission.
{"title":"Materials Research in a Knowledge-Based & Innovation-Driven Singapore","authors":"T. Hor","doi":"10.1142/S0219607710000668","DOIUrl":"https://doi.org/10.1142/S0219607710000668","url":null,"abstract":"The pace of growth for research in Singapore is nothing short of spectacular. Though still in its infancy compared to the might of research giants like Finland, Norway, Israel, Japan, USA, UK and China, Singapore is rapidly moving into higher gear. This comes at a time when the research and development (R&D) of some of the world's leading nations has stalled due in part to the financial meltdown that has only recently seen signs of recovery. But as the saying goes, the best opportunities are found in times of adversity. The approach that Singapore takes is an astute one. Investment in R&D for a country with no natural resources has to be based on the next best thing — intellectual capital and its people. Developing R&D capabilities in a knowledge-based economy therefore depends first and foremost on our human capital. An integrated effort in education and research is hence crucial. The government has taken the lead in R&D investment. It has set a national target of driving the current level of 2.9% of gross domestic expenditure on research and development (GERD) to 3.5% by 2015 — a significant milestone that would put Singapore in the \"premier league\" of R&D nations. It is with this objective that the new national R&D budget for the next five years will be increased by more than 20% to S$16.1 billion. This increase is justified on the basis of pushing a research agenda that is driven by innovation with an economic mission.","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"49 1","pages":"143-148"},"PeriodicalIF":0.0,"publicationDate":"2010-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86580131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2010-08-01DOI: 10.1142/S0219607710000498
D. Yeo
Introduced or alien freshwater decapod crustaceans from Singapore's reservoirs are documented from the results of an ongoing survey. Four species of decapods were recorded in the reservoirs, viz., one freshwater crayfish, Cherax quadricarinatus (Parastacidae) and three freshwater shrimps, Macrobrachium lanchesteri, M. nipponense, and M. aff. inflatum (Palaemonidae). Native decapods were not found in the actual reservoirs, but in forest stream inlets draining into the reservoirs. All four species were introduced through the ornamental pet trade, indicating the significance of this invasion pathway in Singapore. As yet, no ecological impacts on native ecosystems are known for these introduced species, although the possibility that they could be undergoing a lag phase or of more invasive alien decapods being introduced cannot be discounted.
{"title":"INTRODUCED DECAPOD CRUSTACEANS IN SINGAPORE'S RESERVOIRS","authors":"D. Yeo","doi":"10.1142/S0219607710000498","DOIUrl":"https://doi.org/10.1142/S0219607710000498","url":null,"abstract":"Introduced or alien freshwater decapod crustaceans from Singapore's reservoirs are documented from the results of an ongoing survey. Four species of decapods were recorded in the reservoirs, viz., one freshwater crayfish, Cherax quadricarinatus (Parastacidae) and three freshwater shrimps, Macrobrachium lanchesteri, M. nipponense, and M. aff. inflatum (Palaemonidae). Native decapods were not found in the actual reservoirs, but in forest stream inlets draining into the reservoirs. All four species were introduced through the ornamental pet trade, indicating the significance of this invasion pathway in Singapore. As yet, no ecological impacts on native ecosystems are known for these introduced species, although the possibility that they could be undergoing a lag phase or of more invasive alien decapods being introduced cannot be discounted.","PeriodicalId":80753,"journal":{"name":"Bulletin - Cosmos Club. Cosmos Club (Washington, D.C.)","volume":"52 1 1","pages":"85-90"},"PeriodicalIF":0.0,"publicationDate":"2010-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77338213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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