Fabrication of organic photovoltaic devices by the layer-by-layer polyelectrolyte deposition method

Organic photovoltaic cells were fabricated by the layer-by-layer polyelectrolyte deposition process by which the film thickness can be controlled accurately. Ruthenium/rhenium complexes containing poly(p-phenylenevinylene) and sulfonated polyaniline were used in the process. This new method provides flexibility in the fabrication of multilayer polymeric devices with well-defined structure. © 2005 IEEE.published_or_final_versio

Fabrication of bulk heterojunction photovoltaic devices using sublimable rhenium diimine complexes as photosensitizers

A series of chlorotricarbonyl rhenium (I) bis(phenylimino)acenaphthene (Re-DIAN-X) complexes were used as the photosensitizers for photovoltaic cells. Unlike other transition-metal-based photovoltaic sensitizers that can only be prepared by solution method, these complexes are sublimable. Compared to other rhenium diimine complexes based on bipyridine or 1,4-diaza-1,3-butadiene ligands, these complexes have lower band gaps, which can be modified easily by changing the structure of the ligand. It allows the preparation of blend of metal complexes in order to broaden the sensitization region in UV-vis absorption spectrum. One of the complexes also shows bipolar charge transport character with relatively high charge carrier mobilities in the order of 10 -3 cm2V-1s-1. Multilayer heterojunction and bulk heterojunction devices with fullerene as the electron accepting molecule were prepared. For the bulk heterojunction devices, the fill factor and power conversion efficiency under AM 1.5 simulated solar light illumination were 0.51 and 1.29 %, respectively. The effects of changing the Re-DIAN/C60 film thickness, Re-DIAN/C60 ratio and variation of ligand structures in the bulk heterojunction devices were studied. The amount of photosensitizer and electron transport molecules may strongly affect the balance between the photon absorption, exciton formation, dissociation, and charge transport processes. Atomic force microscopic images showed that the complex dispersed evenly with fullerene molecules in solid state.published_or_final_versio

Fabrication of Photovoltaic Cell from Ruthenium Containing Polymer Using Layer by Layer Polyelectrolytes Adsorption Technique

Multilayer photovoltaic devices were fabricated by the sequence adsorption of different polyelectrolytes. A ruthenium terpyridine complex containing poly(p-phenylenevinylene) was used as the polycation layer. This polymer has been shown to exhibit large photo-sensitivity due to the presence of the ruthenium complex, which has relatively long-lived excited state. This polymer absorbs strongly in the visible region at ca. 480-550 nm and it can act as the electron transporter. Sulfonated polyaniline was used as the hole-transporting polyanion layer. The ITO/(polyanion/polycation) n/A1 devices were found to exhibit photovoltaic properties under the illumination of AM1 solar radiation. The short-circuit current I sc, open-circuit voltage V oc, and the fill factor FF were measured to be 14 μA/cm 2, 0.84 V and 0.16 respectively. It was found that the power conversion efficiencies of the devices were dependent on the device thickness. This simple layer-by-layer self-assembly method allowed us to control the devices thickness accurately.published_or_final_versio

Regulation of epithelial mesenchymal transition (EMT) by Serum Amyloid A 1 (SAA1) is dependent on integrin in esophageal squamous cell carcinoma (ESCC)

Poster abstract: no. B5Esophageal Squamous Cell Carcinoma (ESCC) is the predominant type comprising more than 90% of esophageal cancer, which is a highly metastatic and fatal cancer, and is ranked the eighth in mortality rate in Hong Kong cancer patients (Hong Kong Cancer Registry, Hospital Authority, 2010). Using a functional complementation approach, SAA1 was identified as one of the tumor suppressor gene candidates. The SAA1 is an acute phase protein, which is highly expressed in response to inflammation by the liver. It is also present as a secretary protein in histologically normal human epithelial tissues. The expression of SAA1 was found to be down-regulated in ESCC. Interestingly, the gene expression of SAA1 and the mesenchymal marker N-cadherin was found to be inversely correlated in a panel of ESCC and the immortalized esophageal epithelial cell lines. Therefore, we want to determine whether SAA1 could regulate EMT in ESCC ...postprin

Differential angiogenic roles of serum amyloid A 1 (SAA1) isoforms in esophageal squamous cell carcinoma (ESCC)

Molecular and Cellular Biology - Poster Presentations - Proffered Abstracts - Poster Presentations - Tumor Suppressors 2: abstract no. 1550This journal suppl. entitled: Proceedings: AACR Annual Meeting 2014; April 5-9, 2014 ...Esophageal Caner (EC), a highly metastatic and fatal cancer, is ranked the eighth in mortality rate in Hong Kong cancer patients (Hong Kong Cancer Registry, Hospital Authority, 2010). Esophageal Squamous Cell Carcinoma (ESCC) is the predominant type comprising more than 90% of EC. Using a functional complementation approach, SAA1 was identified as one of the tumor suppressor gene candidates. SAA1 is located at chromosome 11p15.1 and is expressed as a secretary protein in liver, human cultured smooth muscle cells, monocyte-macrophage cell lines, and in histologically-normal human epithelial tissues. Genetic polymorphisms of SAA1 have been identified as a risk factor of diseases such as amyloidosis. Three SAA1 isoforms with two ...postprin

Low-band-gap, sublimable rhenium(I) diimine complex for efficient bulk heterojunction photovoltaic devices

The fabrication of efficient bulk heterojunction photovoltaic cells using the chlorotricarbonyl rhenium(I) diimine complex as photosensitizer was discussed. The complex has a lower band gap, which can be adjusted easily by changing the structure of the ligand. The electric properties of the complex were studied using time-of-flight analysis. It was observed that the rhenium complex showed bipolar charge transport character with relatively high electron and hole mobilities.published_or_final_versio

Efficient bulk heterojunction photovoltaic cells using sublimable transition metal complex as photosensitizers

Multilayer bulk heterojunction photovoltaic cells using chlorotricarbonyl rhenium (I) bis(phenylimino)acenaphthene (Re-DIAN) complex as photosensitizer were studied. The complex is sublimable, has lower band gap, good thermal stability and good processibility. It has broad absorption in UV-visible region. Therefore, Re-DIAN exhibits good photosensitising property for photovoltaic cells. Multilayer bulk heterojunction photovoltaic cells with simple structures were fabricated base on Re-DIAN complex. The active layer consists of a blend of Re-DIAN and fullerene that were co-deposited in the same layer by vacuum deposition. The photovoltaic properties of the devices were studied by irradiaton under AM 1.5 simulated solar light. The effects of changing the co-deposition film thickness, amount of Re-DIAN photosensitizer, and hole transporting materials were studied. © 2005 Materials Research Society.published_or_final_versio

Use of the SAW sensor electronic nose for detecting the adulteration of virgin coconut oil with RBD palm kernel olein.

An electronic nose (zNose™) was applied to the detection of adulteration of virgin coconut oil. The system, which is based on a surface acoustic wave sensor was used to generate a pattern of volatile compounds present in the samples. Virgin coconut oil was mixed with refined, bleached and deodorized palm kernel olein at a level of adulteration from 1 to 20% (wt/wt). Adulterant peaks were identified from the chromatogram profile and fitted to a curve using linear regression. The best relationship (R 2 = 0.91) was obtained between the peak tentatively identified as methyl dodecanoate and the percentage of palm kernel olein added. Pearson’s correlation coefficients (r) of 0.92 and 0.89 were obtained between adulterant peak methyl dodecanoate and of the iodine and peroxide values, respectively. Principal component analysis (PCA) was used to differentiate between pure and adulterated samples. The PCA provided good differentiation of samples with 74% of the variation accounted for by PC 1 and 17% accounted for by PC 2. Pure samples formed a separate cluster from all of the adulterated samples

Clinicopathological significance of homeoprotein Six1 in hepatocellular carcinoma

Tumour recurrence and metastases of hepatocellular carcinoma (HCC) after hepatectomy are the major obstacles of long-term survival. The present study investigated the clinicopathological significance of a possible metastasis regulator Six1 in HCC patients who were undergone hepatectomy. Seventy-two pairs of RNA and 103 pairs of protein from tumour and adjacent nontumour liver tissues of HCC patients were examined. About 85 and 60% of HCC tumour tissues were found to overexpress Six1 mRNA and protein, respectively, compared with nontumour liver tissues. No Six1 protein was detected in HCC nontumour liver tissues and normal liver tissues. Increased Six1 protein expression in HCC patients was significantly correlated with pathologic tumour-node-metastasis (pTNM) stage (P=0.002), venous infiltration (P=0.004) and poor overall survival (P=0.0423). We concluded that Six1 is frequently overexpressed in HCC patients and elevated Six1 protein in HCC patients may be an indication of advanced stage and poor overall survival after hepatectomy

Chronic hepatitis B: whom to treat and for how long? Propositions, challenges, and future directions

Recent guidelines of the American Association for the Study of Liver Diseases, the European Association for the Study of the Liver, and the Asian Pacific Association for the Study of the Liver 2008 update of the “Asian-Pacific consensus statement on the management of chronic hepatitis B” offer comprehensive recommendations for the general management of chronic hepatitis B (CHB). These recommendations highlight preferred approaches to the prevention, diagnosis, and treatment of CHB. Nonetheless, the results of recent studies have led to an improved understanding of the disease and a belief that current recommendations on specific therapeutic considerations, including CHB treatment initiation and cessation criteria, particularly in patient populations with special circumstances, can be improved. Twelve experts from the Asia-Pacific region formed the Asia-Pacific Panel Recommendations for the Optimal Management of Chronic Hepatitis B (APPROACH) Working Group to review, challenge, and assess relevant new data and inform future updates of CHB treatment guidelines. The significance of and controversy about reported findings were discussed and debated in an expert meeting of the Working Group in Beijing, China, in November 2008. This review paper attempts to identify areas requiring improved CHB management and provide suggestions for future guideline updates, with special emphasis on treatment initiation and duration