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The use of single-walled carbon nanotubes (CNT) thin films to replace conventional fluorine-doped tin oxide (FTO) and both FTO and platinum (Pt) as the counter electrode in dye sensitized solar cells (DSSC) requires surface modification due to high sheet resistance and charge transfer resistance. In this paper, we report a simple, solution-based method of preparing FTO-free counter electrodes based on metal (Pt) or metal sulfide (Co(8.4)S(8), Ni(3)S(2)) nanoparticles/CNT composite films to improve device performance. Based on electrochemical studies, the relative catalytic activity of the composite films was Pt > Co(8.4)S(8) > Ni(3)S(2). We achieved a maximum efficiency of 3.76% for the device with an FTO-free counter electrode (Pt/CNT). The device with an FTO- and Pt-free (CoS/CNT) counter electrode gives 3.13% efficiency.

The aim of this study was to determine if components of the COPD Assessment Test (CAT), a validated health status impairment instrument, had additional utility in identifying patients at risk for COPD in whom spirometry testing is appropriate. This study was part of the Canadian Obstructive Lung Disease prevalence study. Consenting participants ≥ 40 years of age were identified by random digit dialing. Smoking history, 8-item CAT scores, and post-bronchodilator spirometry were recorded for each. Stepwise logistic regression analysis was used to identify variables related to the presence of airway obstruction and a final logistic model was developed which best predicted COPD in this sample. Of the 801 individuals approached, 532 were included: 51 (9.6%) had COPD, the majority (92%) of whom fit GOLD I or II severity criteria. Items that correlated significantly with a COPD diagnosis included the CAT total score (p = 0.01) and its breathlessness (p < 0.0001) and phlegm (p = 0.001) components. The final logistic model included: age (<55 or ≥55 years), smoking status (current, former, never) and the CAT breathlessness score (ordinal scale 0-5). The area under the receiver-operating characteristic curve for this model was 0.77, sensitivity was 77.6%, specificity was 64.9% and the positive likelihood ratio was 2.21. In summary, the triad of smoking history, age at least 55 years and the presence of exertional breathlessness were key elements of a simple model which had reliable measurement properties when tested in a random population. This may help identify patients at risk for COPD for whom spirometry testing is recommended.

Biventricular pacing (BiV) has been shown to reduce wall stress and workload in regions near the pacing sites. This trial investigated if BiV near the ischemic region would reduce chest pain in patients with refractory angina due to severe coronary artery disease (CAD). Eleven patients were implanted with BiV devices with leads positioned at or adjacent to their ischemic regions as detected by single-photon emission computed tomography (SPECT) and randomized to either pacing turned ON or OFF for 3 months, and then crossed over for 3 months. With pacing turned ON, a Dynamic atrioventricular (AV) delay was set for approximately 90% and 70% of the intrinsic AV delay at the resting heart rate and at the onset of symptoms, respectively. One patient was excluded from the analysis due to a large amount of RV pacing during the OFF periods (24-64%) and due to an inability to properly deliver therapy because of an excessive number of ventricular premature complexes. Overall, with the device ON vs. OFF, the number of angina episodes (0.8 ± 0.4 vs. 1.2 ± 0.7 per week, P = 0.03) and amount of nitroglycerin used (0.2 ± 0.1 vs. 1.0 ± 0.7 per week, P = 0.11) was lower with BiV pacing. Furthermore, the treadmill exercise time to symptoms trended higher (427 ± 65 vs. 408 ± 64 s, P = 0.19), and the sum of fluorodeoxyglucose-positron emission tomography (FDG-PET) scores trended lower (7.9 ± 3.5 vs. 12.0 ± 4.0, P = 0.11) with the device ON vs. OFF. Nevertheless, there were no significant differences in SPECT myocardial perfusion scores, left ventricle ejection fraction, wall motion score index, and quality of life scores with device programmed ON vs. OFF (all P > 0.05). In conclusion, this pilot study demonstrated that BiV-P at or near the ischemic region was feasible and associated with significant reductions in angina in patients with severe CAD. Adequately powered prospective studies are needed to confirm these findings.

Background: Serological studies for influenza infection and vaccine response often involve microneutralization and hemagglutination inhibition assays to evaluate neutralizing antibodies against human and avian influenza viruses, including H5N1. We have previously characterized lentiviral particles pseudotyped with H5-HA (H5pp) and validated an H5pp-based assay as a safe alternative for high-throughput serological studies in BSL-2 facilities. Here we show that H5-HAs from different clades do not always give rise to efficient production of H5pp and the underlying mechanisms are addressed., Methodology/findings: We have carried out mutational analysis to delineate the molecular determinants responsible for efficient packaging of HA from A/Cambodia/40808/2005 (H5Cam) and A/Anhui/1/2005 (H5Anh) into H5pp. Our results demonstrate that a single A134V mutation in the 130-loop of the receptor binding domain is sufficient to render H5Anh the ability to generate H5Anh-pp efficiently, whereas the reverse V134A mutation greatly hampers production of H5Cam-pp. Although protein expression in total cell lysates is similar for H5Anh and H5Cam, cell surface expression of H5Cam is detected at a significantly higher level than that of H5Anh. We further demonstrate by several independent lines of evidence that the behaviour of H5Anh can be explained by a stronger binding to sialic acid receptors implicating residue 134., Conclusions: We have identified a single A134V mutation as the molecular determinant in H5-HA for efficient incorporation into H5pp envelope and delineated the underlying mechanism. The reduced binding to sialic acid receptors as a result of the A134V mutation not only exerts a critical influence in pseudotyping efficiency of H5-HA, but has also an impact at the whole virus level. Because A134V substitution has been reported as a naturally occurring mutation in human host, our results may have implications for the understanding of human host adaptation of avian influenza H5N1 viruses.

Background: Current HIV-1 antiretroviral therapy (ART) greatly reduces virus replication but does not significantly affect the viral reservoir. Raltegravir, a recently introduced integrase inhibitor, could, at least theoretically, reduce residual viremia in patients on ART and affect the viral reservoir size. The aim of this study was to assess whether switching therapy in treatment-experienced patients that were virally suppressed to a raltegravir-containing regimen reduces the size of the viral reservoir, and if such treatment leads to a change in levels of HIV 2-LTR circles in this patient group., Methods: 14 ART experienced individuals with a suppressed viral load (<50 HIV-1 RNA copies/mL plasma) at baseline (for at least 2 months) were switched to a raltegravir-containing regimen. Blood samples were taken at baseline and at ≥2 timepoints up to 48±6 weeks. Levels of total HIV-1 DNA and 2-LTR circles in peripheral blood mononuclear cells (PBMCs) were measured using real-time PCR assays., Results: There was no significant change in HIV-1 total DNA levels over the study duration (p = 0.808), median slope 0.24 (conservative nonparametric 95% CI: -11.78, 26.23). Low levels of 2-LTR circles were detected in 2 patients. One had 16 copies/10(6) PBMCs at baseline and the other had 34 copies/10(6) PBMCs at week 51., Conclusions: The switch to a raltegravir containing regimen was not associated with a significant change in HIV-1 total DNA levels in this cohort. There were no observed changes in the levels of HIV-1 2-LTR circles associated with raltegravir treatment initiation.

Background: While statin induces plaque regression, its effects, particularly with different doses on plaque virtual histology composition, remain unknown., Methods and Results: In this prospective, randomized, double-blinded study, 40 consecutive statin-naive patients with stable angina requiring percutaneous coronary intervention (PCI) were randomized to 2 arms (20 patients each) receiving 6 months of atorvastatin 10 mg or 40 mg daily. The primary end-point was (VH-IVUS) changes from baseline to 6 months, as assessed by a core laboratory. Fifty-four VH-IVUS lesions were analyzed from the 10 mg group and 57 from the 40 mg group. Overall, plaque volume was reduced by 4.28% (-5.10±14.93 mm(3), P<0.001), absolute VH-IVUS fibrous volume by 10.54% (-4.87±10.74 mm(3), P<0.001), and relative percentage fibrous component by 3.29±7.84% (P<0.001), while relative percentage dense calcium increased by 1.50±3.08% (P<0.001), and necrotic core by 3.19±7.82% (P<0.001). Beneficial changes were more substantial in the higher dose (40 mg) group, with significantly more percentage plaque volume regression (-1.50±3.85% vs. 0.38±4.05% increase in the 10 mg group, P=0.014), less relative percentage necrotic core expansion (1.68±7.57% vs. 4.78±7.82% in the 10 mg group, P=0.037), and without occurrence of major adverse cardiac events (vs. 6 patients in the 10 mg group, P=0.020)., Conclusions: In statin-naive patients requiring PCI, 6 months of atorvastatin induced a significant percentage of plaque volume reduction and substantial modification of VH-IVUS composition. In addition, these effects appeared to vary with different doses of atorvastatin, showing significantly better limitation of relative percentage necrotic core expansion at a higher dose.

A solution processed method for fabricating transition metal sulfides on fluorine doped tin oxide (FTO) as efficient counter electrodes in iodine/iodide based solar cells has been demonstrated. Conversion efficiencies of 7.01% and 6.50% were obtained for nickel and cobalt sulfides, respectively, comparable to the conventional thermally platinised FTO electrodes (7.32%). A comparable charge transfer resistance of Ni(3)S(2) and Co(8.4)S(8) to conventional Pt was found to be a key factor for such high efficiencies. Cyclic voltammetry, Kelvin probe microscopy, Electrochemical Impedance Spectroscopy, and Tafel polarization were performed to study the underlying reasons behind such efficient counter electrode performance., (This journal is © the Owner Societies 2011)

A novel chemically stable Zn-Sn-O nanocactus structure has been synthesized for the first time using a hydrothermal method. The Zn-Sn-O nanocactus structure comprises a Zn poor-Zn(2)SnO(4) plate and Zn-doped SnO(2) nanothorns growing on the plate, both of which have high electron mobilities. The nanocactus is used as the photoanode of dye-sensitized solar cells (DSSCs). The overall power conversion efficiency (PCE) for the Zn-Sn-O nanocactus film reaches 2.21%, which is twice the previous reported efficiency of pure SnO(2). Electrochemical impedance spectroscopy (EIS) measurements show that the Zn-Sn-O nanocactus film has a good effective diffusion length and high intrinsic electron mobility. After TiCl(4) treatment of the Zn-Sn-O nanocactus film, the current density increases nearly three times and the PCE increases to 6.62%, which compares favourably with the P25 DSSCs (6.97%) and is much higher than that of the SnO(2) (1.04%) or Zn(2)SnO(4) (3.7%)-based DSSCs.

MnO2 supported on graphene oxide (GO) made from different graphite materials has been synthesized and further investigated as electrode materials for supercapacitors. The structure and morphology of MnO2-GO nanocomposites are characterized by X-ray diffraction, X-ray photoemission spectroscopy, scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and Nitrogen adsorption-desorption. As demonstrated, the GO fabricated from commercial expanded graphite (denoted as GO(1)) possesses more functional groups and larger interplane gap compared to the GO from commercial graphite powder (denoted as GO(2)). The surface area and functionalities of GO have significant effects on the morphology and electrochemical activity of MnO2, which lead to the fact that the loading amount of MnO2 on GO(1) is much higher than that on GO(2). Elemental analysis performed via inductively coupled plasma optical emission spectroscopy confirmed higher amounts of MnO2 loading on GO(1). As the electrode of supercapacitor, MnO2-GO(1) nanocomposites show larger capacitance (307.7 F g-1) and better electrochemical activity than MnO2-GO(2) possibly due to the high loading, good uniformity, and homogeneous distribution of MnO2 on GO(1) support.

The synthesis and characterization is reported of low bandgap [1,2,5]chalcogenazolo[3,4-f]benzo[1,2,3]triazole and [1,2,3]triazolo[3,4-g]quinoxaline derivatives that display higher solubility and stability then their thiadiazole counterparts, [1,2,5]chalcogenazolo[3,4-f]benzo[2,1,3]thiadiazole and [1,2,5]thiadiazolo[3,4-g]quinoxaline, respectively.

Background: Both chronic airway obstruction and obesity are increasing in prevalence but the effect of their combination on pulmonary function parameters across the range of airway obstruction is unknown., Methods: We studied the impact of increasing BMI on static lung volumes and airway function in a cohort of 2,265 subjects from a large pulmonary function laboratory database who were 40 to 80 years of age and met GOLD (Global Initiative for Chronic Obstructive Lung Disease) spirometric criteria for COPD (postbronchodilator FEV₁/FVC < 0.7). We also evaluated the influence of severity of airway obstruction (by GOLD criteria) on these relationships., Results: With increasing BMI in the group as a whole, functional residual capacity, residual volume, expiratory reserve volume, and specific airway resistance (sRaw) decreased exponentially (all P < .001); total lung capacity (TLC) decreased linearly (P < .001); and inspiratory capacity (IC) and IC/TLC increased linearly (P < .001). However, vital capacity was not influenced significantly. The effects of increasing BMI on FEV₁/FVC and sRaw were greatest in GOLD stage III/IV (P < .05), whereas increasing BMI had greater effects on IC in GOLD stage I (P < .001)., Conclusions: With increasing BMI, subjects with airway obstruction had consistent reductions in lung hyperinflation, with significant improvements in IC and the FEV₁/FVC ratio; this effect was greatest in patients with the most severe airway obstruction. These results have important implications for the clinical assessment of patients with combined obesity and airway obstruction.

In this paper, CdSe nanocrystal dissolution in an aqueous solution was studied. It was found that light is a key factor affecting the dissolution of nanocrystals. In the presence of light, the electrons generated from CdSe nanocrystals reduce water to hydrogen and hydroxide ions (OH-) while photo-generated holes oxidize CdSe to Cd2+ and elemental Se. The dissolution was accelerated in an acidic medium while moderate alkalinity (pH=10.3) can slow down the dissolution possibly due to precipitation of nanocrystals. This study has strong implications for the use of these crystals in aqueous environments (bioimaging and dye-sensitized solar cells).

Self-assembly of peptides provides the possibility of achieving relatively long range order on surfaces. These ordered peptides can also form channels that can be used as conduction channels. In the past, studies were focused on electron conduction through the secondary structure and amine bond of peptides and these restrict conduction of electrons over a short range (a few nanometers). In this work, we demonstrate the realization of electron conduction over a longer range of a few hundred nanometers via π-π stacking of the phenyl groups in the tyrosine residue of a single peptide. The peptide used in this work was designed with a phenyl ring for π-π stacking at one end and a carboxylic group at the other end for binding to aminopropyltriethoxysilane (APTES) treated silicon wafer. The distance between the peptides is controlled by a disulfide bond formed between neighboring cysteine residue and also by the amine groups of aminopropyltriethoxysilane. We demonstrate that the self-assembled peptide is conducting in the dry state over hundreds of nanometers, realizing the possibility of using peptide as a molecular wire.

Population-based studies have demonstrated differences in intima-media thickness (IMT) measured from the left and right common carotid arteries (CCAs). However, its prognostic implications among patients with established coronary artery disease (CAD) remain unknown. Correlations between the left and right CCAs and the composite end point of cardiac death or nonfatal acute coronary syndrome among 149 patients with angiographically confirmed stable CAD were studied. A total of 22 patients had cardiovascular events during the 32.1 ± 10.9 months follow-up. Multivariate analysis revealed that prior ischemic stroke (hazard ratio [HR]: 15.36, 95% confidence interval [CI]: 4.49-52.59, P < .001), extent of CAD (HR: 1.56, 95%CI: 1.01-2.42, P = .046), and right CCA IMT (HR: 17.07, 95%CI: 2.16-134.69, P = .007) but not the left CCA IMT, independently predicted cardiovascular events. The right CCA IMT independently predicted event-free survival among patients with established CAD, suggesting that the left and right CCA may exhibit different prognostic values in our population.

In this study, we use solution-processable crystalline TiO(2) nanoparticles as a buffer layer between the active layer and aluminum cathode to fabricate the P3HT:PCBM-based bulk heterojunction (BHJ) organic photovoltaic (OPV) devices. The employment of the presynthesized TiO(2) nanoparticles simplifies the fabrication of OPV devices because of the elimination of an additional hydrolysis step of precursors in air. The fabricated OPV devices with the thermally stable TiO(2) buffer layer are subjected to the further postdeposition thermal annealing, resulting in a power conversion efficiency (PCE) as high as 3.94%. The improved device performance could be attributed to the electron transporting and hole blocking capabilities due to the introduced TiO(2) buffer layer., (© 2011 American Chemical Society)

Background: The purpose of this study was to describe the clinical characteristics and clinical outcomes for Chinese patients with type A intramural hematoma (IMH)., Methods and Results: We studied 90 patients with Stanford type A acute aortic syndrome who presented to our institution from 1998 to 2005 and evaluated the presentation, management, and clinical outcomes of acute IMH by comparing these patients with those diagnosed with classical aortic dissection (AD). A total of 34 patients had IMH and they tended to be older (69.7 ± 12.4 versus 60.5 ± 16.2 years; p=0.006). The development of pericardial effusion was more frequent in patients with IMH than in patients with AD. They were also less likely to receive surgery as compared to AD patients (26.5% versus 73.2%; p<0.0001). Overall mortality of IMH was not significantly higher than that of classic AD (29.4% versus 21.4%; p=0.45). For IMH patients, the mortality rate with medical treatment was 32%. Ten (40%) of the 25 medically treated patients developed adverse outcomes. However, no independent predictors of adverse outcomes were identified in the study. In follow-up imaging studies of 15 patients who survived IMH without surgical repair, 14 patients showed complete resolution of IMH and 1 progressed into classical AD., Conclusion: Acute type A IMH in Chinese patients showed a high mortality rate with medical treatment. It has a highly unpredictable course with no reliable clinical and anatomical predictors. Surgical therapy should be the treatment of choice for Chinese patients with acute IMH, especially those who are younger and have less comorbidities., (© 2011 Wiley Periodicals, Inc.)

For hybrid solar cells, interfacial chemistry is one of the most critical factors for good device performance. We have demonstrated that the size of the surface ligands and the dispersion of nanoparticles in the solvent and in the polymer are important criteria in obtaining optimized device performance. The size of the ligands will affect the charge transport at the particle/particle and particle/polymer interfaces and the chemical structures of the ligands will determine their compatibility with the solvent and polymer. Hence other than pyridine, 2-thiophenemethylamine also showed good potential as ligand replacement for poly(3-hexylthiophene)/CdSe hybrid solar cells. With the right ligand combination, we have shown that the power conversion efficiency improved by a factor of 6 after ligand exchange.

The reduction of a dithienylbenzobisthiadiazole derivative TBBT can be performed selectively so as to afford either [1,2,5]-thiadiazolo[3,4-g]quinoxaline (TQ) or pyrazino[2,3-g]quinoxaline (PQ) derivatives. This approach offers a much milder, shorter, and more efficient route to PQ and TQ derivatives than current methods. It is further shown how the optical and electrochemical properties of PQ and TQ can be tuned by choice of appropriate substituents.

Objective: Researchers commonly use the femoral shaft-tibial shaft angle (FS-TS) from knee radiographs to estimate the hip-knee-ankle angle (HKA) in studies examining risk factors for knee osteoarthritis (OA) incidence and progression. The objective of this study was to determine the relationship between HKA and FS-TS, depending on the method of calculating FS-TS and the direction and degree of knee deformity., Methods: 120 full-length digital radiographs were assigned, with 30 in each of four alignment groups (0.0°-4.9°, and ≥5.0° of varus and valgus), from a large cohort of persons with and at risk of knee OA. HKA and five measures of FS-TS (using progressively shorter shaft lengths) were obtained using Horizons Analysis Software, Orthopaedic Alignment & Imaging Systems Inc. (OAISYS). The offsets between HKA and the different versions of FS-TS were calculated, with 95% confidence intervals (CIs). Pearson correlations were calculated., Results: In varus limbs use of a shorter shaft length increased the offset between HKA and FS-TS from 5.1° to 7.0°. The opposite occurred with valgus limbs (from 5.0° to 3.7°). Correlations between HKA and FS-TS for the whole sample of 120 individuals were excellent (r range 1.00-0.88). However, correlations for individual alignment groups were low to moderate, especially for the shortest-shaft FS-TS (r range 0.41-0.66)., Conclusions: The offsets obtained using the shorter FS-TS measurements vary depending on direction and degree of knee deformity, and therefore may not provide reliable predictions for HKA We recommend that full-length radiographs be used whenever an accurate estimation of HKA is required, although broad categories of alignment can be estimated with FS-TS., (Copyright © 2010 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.)

Objective: To explore the experience and attitudes of physicians in clinics, and to facilitate physicians' promotion of HPV vaccination., Data Sources: Primary data collected from conducting semi-structural in-depth interviews from May to June 2010 with 12 physicians in one district in Hong Kong to understand their experience of providing HPV vaccines, the difficulties in promoting HPV vaccines, and their attitudes towards HPV vaccination., Study Design: Physicians identified 4 categories of factors related to their experiences of and attitudes to providing HPV vaccination: (a) background information on HPV vaccination provided by physicians, (b) factors influencing women to receive vaccination, (c) physicians' recommendations to the public on HPV vaccines, and (d) physicians' perspectives on HPV vaccine promotion., Conclusions: Our findings show that public knowledge on HPV and cervical cancer is insufficient and the role of government in vaccine promotion is unclear. Promotion strategies such as physicians' recommendation, financial assistance and health education provided by the government will influence HPV vaccination and its promotion.

The natural history of lung hyperinflation in patients with airway obstruction is unknown. In particular, little information exists about the extent of air trapping and its reversibility to bronchodilator therapy in those with mild airway obstruction. We completed a retrospective analysis of data from individuals with airway obstruction who attended our pulmonary function laboratory and had plethysmographic lung volume measurements pre- and post-bronchodilator (salbutamol). COPD was likely the predominant diagnosis but patients with asthma may have been included. We studied 2,265 subjects (61% male), age 65 ± 9 years (mean ± SD) with a post-bronchodilator FEV(1)/FVC <0.70. We examined relationships between indices of airway obstruction and lung hyperinflation, and measured responses to bronchodilation across subgroups stratified by GOLD criteria. In GOLD stage I, vital capacity (VC) and inspiratory capacity (IC) were in the normal range; pre-bronchodilator residual volume (RV), functional residual capacity (FRC) and specific airway resistance were increased to 135%, 119% and 250% of predicted, respectively. For the group as a whole, RV and FRC increased exponentially as FEV(1) decreased, while VC and IC decreased linearly. Regardless of baseline FEV(1), the most consistent improvement following bronchodilation was RV reduction, in terms of magnitude and responder rate. In conclusion, increases (above normal) in airway resistance and plethysmographic lung volumes were found in those with only minor airway obstruction. Indices of lung hyperinflation increased exponentially as airway obstruction worsened. Those with the greatest resting lung hyperinflation showed the largest bronchodilator-induced volume deflation effects. Reduced air trapping was the predominant response to acute bronchodilation across severity subgroups.

Background: Noninvasive prenatal diagnosis of fetal aneuploidy by maternal plasma analysis is challenging owing to the low fractional and absolute concentrations of fetal DNA in maternal plasma. Previously, we demonstrated for the first time that fetal DNA in maternal plasma could be specifically targeted by epigenetic (DNA methylation) signatures in the placenta. By comparing one such methylated fetal epigenetic marker located on chromosome 21 with another fetal genetic marker located on a reference chromosome in maternal plasma, we could infer the relative dosage of fetal chromosome 21 and noninvasively detect fetal trisomy 21. Here we apply this epigenetic-genetic (EGG) chromosome dosage approach to detect Edwards syndrome (trisomy 18) in the fetus noninvasively., Principal Findings: We have systematically identified methylated fetal epigenetic markers on chromosome 18 by methylated DNA immunoprecipitation (MeDIP) and tiling array analysis with confirmation using quantitative DNA methylation assays. Methylated DNA sequences from an intergenic region between the VAPA and APCDD1 genes (the VAPA-APCDD1 DNA) were detected in pre-delivery, but not post-delivery, maternal plasma samples. The concentrations correlated positively with those of an established fetal genetic marker, ZFY, in pre-delivery maternal plasma. The ratios of methylated VAPA-APCDD1(chr18) to ZFY(chrY) were higher in maternal plasma samples of 9 male trisomy 18 fetuses than those of 27 male euploid fetuses (Mann-Whitney test, P=0.029). We defined the cutoff value for detecting trisomy 18 fetuses as mean+1.96 SD of the EGG ratios of the euploid cases. Eight of 9 trisomy 18 and 1 of 27 euploid cases showed EGG ratios higher than the cutoff value, giving a sensitivity of 88.9% and a specificity of 96.3%., Conclusions: Our data have shown that the methylated VAPA-APCDD1 DNA in maternal plasma is predominantly derived from the fetus. We have demonstrated that this novel fetal epigenetic marker in maternal plasma is useful for the noninvasive detection of fetal trisomy 18.

Block copolymers are useful for in situ synthesis of nanoparticles as well as producing nanoporous templates. As such, the effects of precursors on the block copolymer micelle structure is important. In this study, we investigate the effects of polarity of molecules introduced into block copolymer micelle cores on the micelle structure. The molecular dipole moment of the additive molecules has been evaluated and their effects on the block copolymer micelles investigated using light scattering spectroscopy, small-angle X-ray scattering, transmission electron microscopy and atomic force microscopy. The molecule with the largest dipole moment resulted in spherical structures with a polydispersity of less than 0.06 in a fully translational diffusion system. Surprisingly, the less polar additive molecules produced elongated micelles and the aspect ratio increases with decreasing polarity. The change in structure from spherical to elongated structure was attributed to P4VP chain extension, where compounds with polarity most similar to P4VP induce the most chain extension. The second virial coefficients of the solutions with elongated micelles are lower than that for spherical micelle systems by up to one order in magnitude, indicating a strong tendency for micelles to coalesce. On rinsing the spin-cast films, pores were obtained from spherical micelles and ridges from elongated micelles, suggesting a viable alternative for morphology modification using mild conditions where external annealing treatments to the film are not preferred. The knowledge of polarity effects of additive molecules on micelle structure has wider implications for supramolecular block copolymer systems where, depending on the application requirements, changes to the shape of the micelle structure can be induced or avoided., (Copyright 2010 Elsevier Inc. All rights reserved.)

The chemically reduced graphene oxide (rGO) was transferred onto polyethylene terephthalate (PET) substrates and then used as transparent and conductive electrodes for flexible organic photovoltaic (OPV) devices. The performance of the OPV devices mainly depends on the charge transport efficiency through rGO electrodes when the optical transmittance of rGO is above 65%. However, if the transmittance of rGO is less than 65%, the performance of the OPV device is dominated by the light transmission efficiency, that is, the transparency of rGO films. After the tensile strain (∼2.9%) was applied on the fabricated OPV device, it can sustain a thousand cycles of bending. Our work demonstrates the highly flexible property of rGO films, which provide the potential applications in flexible optoelectronics.

A one-step synthesis of 4,8-dibromobenzo[1,2-c;4,5-c']bis[1,2,5]thiadiazole with use of 1,2,4,5-tetraaminobenzene tetrahydrobromide and thionyl bromide in good yield is reported. This unit can then be used in the synthesis of low bandgap materials via palladium-catalyzed coupling reactions. The approach offers a quick and easy way to prepare low bandgap materials as compared to the current literature methods.

Background: We evaluated the long term clinical outcomes of femoral vascular closure devices following its deployment in coronary angiography and percutaneous coronary intervention (PCI) procedures., Methods: From June 2000 to September 2004, 265 patients who received femoral vascular closure devices after coronary angiography and PCIs were enrolled into the study. Patients' medical records were reviewed and vascular complications within 1 year of follow-up period were recorded. Rutherford's categories of claudication were used to quantify different degrees of claudication and leg ischaemia. Duplex ultrasonography of both femoral arteries (using the nonaccessed site as control) was performed at 1 year after deployment of vascular closure devices. Vessel diameter and flow velocities for both common femoral arteries were obtained., Results: There was no occurrence of late vascular complications like arteriovenous fistula, pseudoaneurysm, surgical repair of access site complications, late groin bleeding and infection. By Rutherford categories of claudication, 99.2% of patients had grade 0 claudication while the remaining 0.8% was in grade 1. By arterial Duplex ultrasonography, the peak systolic velocity of the accessed femoral artery (predominantly right side) was nonsignificantly higher, 94.9 + or - 26.0 cm/s when compared to 91.5 + or - 24.8 cm/s in the control site (P = 0.12). As for vessel diameter, no significant difference was found in the mean end-diastolic vessel diameter 8.8 + or - 1.3 mm (puncture site) versus 8.7 + or - 4.4 mm (control site) (P = 0.72)., Conclusion: We found that the use of femoral closure devices was safe and it was not associated with any adverse long term vascular complications.

We report a patient with isolated left ventricular non-compaction diagnosed by echocardiography and cardiac magnetic resonance imaging. She developed refractory congestive heart failure and subsequently underwent successful heart transplantation. This type of cardiomyopathy is thought to be caused by the arrest of normal embryogenesis of the endocardium and myocardium. The spectrum of clinical, radiological, and pathological abnormalities is discussed.

We studied the distribution profiles and repeatability of key exercise performance parameters in the first large multicentre trials to include these measurements in chronic obstructive pulmonary disease (COPD). After a screening visit, 463 subjects with COPD (mean+/-SD forced expiratory volume in 1 s 43+/-13% predicted) completed two run-in visits before treatment randomisation. At the run-in visits, measurements were conducted at rest, at a standardised time near end-exercise (isotime) and at peak exercise during constant work rate (CWR) cycle tests at 75% of each individual's maximum work capacity. The intraclass correlation coefficient was used to evaluate the test-retest repeatability of measurements of endurance time (ET), inspiratory capacity (IC), ventilation and dyspnoea intensity (Borg scale) during exercise. IC, ventilation and dyspnoea ratings were normally distributed; ET showed rightward skew (median or = 0.87). Ventilation was repeatable over the same time-points (R > or = 0.92), as was dyspnoea intensity at isotime (R = 0.79) and at peak exercise (R = 0.81). In conclusion, key perceptual and ventilatory parameters can be reliably measured during CWR cycle exercise in multicentre clinical trials in moderate to very severe COPD.

Background: Patients with symptoms of GOLD stage I chronic obstructive pulmonary disease (COPD) can have significant abnormalities of ventilatory mechanics with greater exertional symptoms and exercise limitation than age-matched healthy subjects. In such patients the impact of bronchodilator therapy remains unknown and is difficult to evaluate., Methods: The acute effects of nebulised ipratropium bromide 500 microg (IB) on resting pulmonary function and on dyspnoea and ventilatory parameters during symptom-limited constant work rate cycle exercise were measured. In a randomised double-blind crossover study, 16 patients with COPD (mean (SD) post-bronchodilator forced expiratory volume in 1 s (FEV(1)) 90 (7)% predicted, FEV(1)/forced vital capacity (FVC) 59 (7)%) with a significant smoking history (mean (SD) 44 (16) pack-years) inhaled either IB or placebo on each of two separate visits. Pulmonary function tests and cycle exercise at 80-85% of each subject's maximal work capacity were performed 2 h after dosing., Results: Compared with placebo, FEV(1) increased 5 (9)% predicted, residual volume decreased 12 (20)% predicted and specific airway resistance decreased 81 (93)% predicted (all p<0.05) after IB. At a standardised time during exercise, dynamic inspiratory capacity and tidal volume significantly increased in tandem by 0.12 and 0.16 litres, respectively (each p<0.05), dyspnoea fell by 0.9 (1.8) Borg units (p = 0.07) and dyspnoea/ventilation ratios fell significantly (p<0.05). The fall in dyspnoea intensity at higher submaximal ventilations correlated with the concurrent decrease in end-expiratory lung volume (p<0.05)., Conclusion: In patients with symptoms of GOLD stage I COPD, IB treatment is associated with modest but consistent improvements in airway function, operating lung volumes and dyspnoea intensity during exercise. These results provide a physiological rationale for a trial of bronchodilator therapy in selected patients with milder but symptomatic COPD.

The crystal structure of seabream antiquitin in complex with the cofactor NAD(+) was solved at 2.8A resolution. The mouth of the substrate-binding pocket is guarded by two conserved residues, Glu120 and Arg300. To test the role of these two residues, we have prepared the two mutants E120A and R300A. Our model and kinetics data suggest that antiquitin's specificity towards the substrate alpha-aminoadipic semialdehyde is contributed mainly by Glu120 which interacts with the alpha-amino group of the substrate. On the other hand, Arg300 does not have any specific interaction with the alpha-carboxylate group of the substrate, but is important in maintaining the active site conformation.

The prevalence of activity-related breathlessness increases with age, particularly in women, but the specific underlying mechanisms have not been studied. This novel cross-sectional study was undertaken to examine the effects of age and sex, and their interaction, on the perceptual and ventilatory responses to incremental treadmill exercise in 73 healthy participants (age range 40-80 yr old) with normal pulmonary function. Age-related changes at a standardized oxygen uptake (Vo(2)) during exercise included significant increases in breathlessness ratings (Borg scale), ventilation (Ve), ventilatory equivalent for carbon dioxide, and the ratio of tidal volume (Vt) to dynamic inspiratory capacity (IC) (all P < 0.05). These changes were quantitatively similar in women (n = 39) and in men (n = 34). For the group as a whole, exertional breathlessness ratings increased as resting static inspiratory muscle strength diminished (P = 0.05), as exercise ventilation increased relative to capacity (P = 0.013) and as the Vt/IC ratio increased (P = 0.003) during exercise. Older women (60-80 yr old, n = 23) reported greater (P < 0.05) intensity of exertional breathlessness at a standardized Vo(2) and Ve than age-matched men (n = 16), despite similar age-related changes in ventilatory demand and dynamic ventilatory mechanics. These increases in breathlessness ratings in older women disappeared when sex differences in baseline maximal ventilatory capacity were accounted for. In conclusion, although increased exertional breathlessness with advancing age is multifactorial, contributory factors included higher ventilatory requirements during exercise, progressive inspiratory muscle weakness, and restrictive mechanical constraints on Vt expansion related to reduced IC. The sensory consequences of this age-related respiratory impairment were more pronounced in women, who, by nature, have relatively reduced maximal ventilatory reserve.

Nanocrystalline cadmium selenide (CdSe) is a low bandgap material (E(g)=1.75 eV, at room temperature) with potential applications in photoelectronic devices. Its electronic properties are dependent on the dimensions of the crystals. In this study, one-dimensional wurtzite CdSe nanoparticles with a diameter of 43+/-6 nm and an aspect ratio of 3.7+/-0.6 were synthesized through a novel reverse micelle assisted hydrothermal method at a relatively low temperature. This method combines the advantages of the hydrothermal method's ability to achieve good crystallinity with the well-controlled growth offered by the reverse micelle method. The morphology of the nanoparticles can be controlled by the amount of sodium bis(2-ethylhexyl) sulfosuccinate (AOT), the amount of hydrazine hydrate and the reaction temperature. It is proposed that AOT controls the length while hydrazine hydrate controls the diameter of the growing nanocrystals. The photoluminescence (PL) of individual nanorods and the longitudinal-optical phonon properties were mapped using confocal microscopy. Raman spectroscopy showed a blue-shift of both the LO and 2LO phonon peaks which may be due to a lattice contraction of the CdSe nanorods. A nucleation and growth mechanism for these nanoparticles is also proposed based on time-dependent studies.

This study examined the role of pregnancy-induced changes in wakefulness (or non-chemoreflex) and central chemoreflex drives to breathe, acid-base balance and female sex hormones in the hyperventilation of human pregnancy. Thirty-five healthy women were studied in the third trimester (TM(3); 36.3+/-1.0 weeks gestation; mean+/-S.D.) and again 20.2+/-7.8 weeks post-partum (PP). An iso-oxic hyperoxic rebreathing procedure was used to evaluate wakefulness and central chemoreflex drives to breathe. At rest, arterialized venous blood was obtained for the estimation of arterial PCO(2) (PaCO(2)) and [H(+)]. Blood for the determination of plasma strong ion difference ([SID]), albumin ([Alb]), as well as serum progesterone ([P(4)]) and 17beta-estradiol ([E(2)]) concentrations was also obtained at rest. Wakefulness and central chemoreflex drives to breathe, [P(4)] and [E(2)], ventilation and V CO(2) increased, whereas PaCO(2) and the central chemoreflex ventilatory recruitment threshold for PCO(2) (VRTCO(2)) decreased from PP to TM(3) (all p<0.01). The reductions in PaCO(2) were not related to the increases in [P(4)] and [E(2)]. The alkalinizing effects of reductions in PaCO(2) and [Alb] were partly offset by the acidifying effects of a reduced [SID], such that arterial [H(+)] was still reduced in TM(3) vs. PP (all p<0.001). A mathematical model of ventilatory control demonstrated that pregnancy-induced changes in wakefulness and central chemoreflex drives to breathe, acid-base balance, V CO(2) and cerebral blood flow account for the reductions in PaCO(2), [H(+)] and VRTCO(2). This is the first study to demonstrate that the hyperventilation and attendant hypocapnia/alkalosis of human pregnancy results from a complex interaction of pregnancy-induced changes in wakefulness and central chemoreflex drives to breathe, acid-base balance, metabolic rate and cerebral blood flow.

Rationale: Smokers with a relatively preserved FEV(1) may experience dyspnea and activity limitation but little is known about underlying mechanisms., Objectives: To examine ventilatory constraints during exercise in symptomatic smokers with GOLD (Global Initiative for Chronic Obstructive Lung Disease) stage I chronic obstructive lung disease (COPD) so as to uncover potential mechanisms of dyspnea and exercise curtailment., Methods: We compared resting pulmonary function and ventilatory responses (breathing pattern, operating lung volumes, pulmonary gas exchange) with incremental cycle exercise as well as Borg scale ratings of dyspnea intensity in 21 patients (post-bronchodilator FEV(1), 91 +/- 7% predicted, and FEV(1)/FVC, 60 +/- 6%; mean +/- SD) with significant breathlessness and 21 healthy age- and sex-matched control subjects with normal spirometry., Measurements and Main Results: In patients with COPD compared with control subjects, peak oxygen consumption and power output were significantly reduced by more than 20% and dyspnea ratings were higher for a given work rate and ventilation (P < 0.05). Compared with the control group, the COPD group had evidence of extensive small airway dysfunction with increased ventilatory requirements during exercise, likely on the basis of greater ventilation/perfusion abnormalities. Changes in end-expiratory lung volume during exercise were greater in COPD than in health (0.54 +/- 0.34 vs. 0.06 +/- 0.32 L, respectively; P < 0.05) and breathing pattern was correspondingly more shallow and rapid. Across groups, dyspnea intensity increased as ventilation expressed as a percentage of capacity increased (P < 0.0005) and as inspiratory reserve volume decreased (P < 0.0005)., Conclusions: Exertional dyspnea in symptomatic patients with mild COPD is associated with the combined deleterious effects of higher ventilatory demand and abnormal dynamic ventilatory mechanics, both of which are potentially amenable to treatment.

There is no surrogate marker in serum for defining disease activity in scleroderma (SSc). Nitric oxide (NO), which regulates vasodilation and possesses pro-inflammatory actions, has been implicated in the pathogenesis of SSc. We compared serum NO(x) (total nitrate and nitrite) level in SSc patients to healthy controls and evaluated its correlation with detailed symptomatology and scoring systems for various organ involvement. Symptoms and physical findings that suggested disease activity in regard to various organs were documented. Lung function test, high-resolution computed tomographic (HRCT) scan of thorax and echocardiography were performed. Serum NO(x) was measured by chemiluminescence. Serum NO(x) levels in SSc (n = 43) were significantly higher (72.4 +/- 47.8 microM) than age- and sex-matched controls (n = 41; 37.1 +/- 13.5 microM; p < 0.001). Serum NO(x) were not found to be associated with lung fibrosis defined by lung function parameters or inflammation and fibrosis scores on HRCT. Twenty-two patients were found to have elevated serum NO(x) level defined as mean +/- 2 SD of normal controls. Logistic regression analysis revealed that age (OR 1.12, p = 0.02) and elevated pulmonary arterial pressure (PAP) (n = 9; OR 145.3, p = 0.01) were predictive factors for elevated serum NO(x). Prednisolone use was associated with lower serum NO(x) level (OR 0.06, p = 0.04). Elevated PAP of increasing severity was found to be associated with higher level of serum NO(x) (p = 0.004 by trend). Serum NO(x) in SSc patients were elevated compared to healthy controls. Serum NO(x) level was determined by multiple factors including age, prednisolone use, and elevated PAP.

Supramolecular self-assemblies in selective solvents give rise to many patterning possibilities. The diblock copolymer polystyrene-b-poly(4-vinylpyridine) (PS-P4VP) is one such polymer that self-assembles into neat nanostructures in toluene. These nanostructures once formed are highly susceptible to solvent influence. Unfortunately, for use as nanotemplates and in the synthesis of nanoparticles, the susceptibility of the films to solvents can be a problem. In this study, we present a method to stabilize the structures through chemical means in solution. We used 1,4-dibromobutane in solution to chemically crosslink the pyridine residues of each of PS-P4VP to yield a series of stable spherical aggregates. In this way, the cross-linking ratio can be precisely controlled. The solution properties were studied using dynamic light scattering and small angle X-ray scattering and the morphology of the resulting micellar film was studied using transmission electron microscopy (TEM). The size of the micelles formed was found to be dependent on the amount of cross-linking and the shape of the PS-P4VP micelles remains stable when exposed to a selective solvent for PS.

In view of efficient and nontoxic delivery of genes to cells, complexes made of phospholipids (noncationic) and DNA are assembled through the mediation of multivalent cations. The association of lipids with DNA is explained through the charge reversal of lipid headgroups by specific adsorption of cations. The ion binding is quantified by the Gouy-Chapman-Stern theory which provides a good estimate for the minimal concentration of cations required to produce complexes. Coarse-grained Monte Carlo calculations support X-ray diffraction experiments in the sense that lipids form inverted micelles around hexagonally arranged DNA rods, with cations in between to maintain the cohesion. The complexes are more cohesive in terms of total free energy as the cation valence increases. The presented methodology may help develop predictive models for biomolecular self-assembled systems.

CdSe nanoparticles have been successfully synthesized using a novel microemulsion method at moderate temperature. It is found that with a combination of the surfactant AOT and hydrazine hydrate, it is possible to control the morphology of the nanoparticles. The hydrazine hydrate acts as both a reducing agent and a templating agent that favors the formation of a rodlike structure. The composition, morphology and optical properties of the CdSe nanoparticles were investigated using powder X-ray diffraction (XRD), transmission electron microscopy (TEM), ultraviolet-visible (UV-vis) absorption spectroscopy, photoluminescence (PL) spectroscopy, energy dispersive X-ray spectroscopy (EDX) and Fourier transform infrared (FT-IR) spectroscopy. The nucleation and growth mechanism for this system is also proposed based on a time-dependent study. This synthesis route provides a moderate temperature (100 degrees C) method for synthesizing rodlike CdSe, hence reducing the possibility of oxidation of this chalcogenide compound.

Self-assembled DNA delivery systems based on cationic lipids are simple to produce and weakly hazardous in comparison with viral vectors, but possess a significant toxicity at high doses. Phospholipids are in contrast intrinsically safe; yet their association with DNA is problematic because of unfavorable electrostatic interactions. We achieve the phospholipid-DNA complexation through the like-charge attraction induced by cations. Monovalent cations are inappropriate due to their poor binding affinity with lipids as inferred from electrophoretic mobility, whereas x-ray diffractions reveal that with multivalent cations, DNA is complexed within an inverted hexagonal liquid-crystalline phase. Coarse-grained Monte Carlo simulations confirm the self-assembly of a DNA rod wrapped into a lipid layer with cations in between acting as molecular glue. Transfection experiments performed with Ca2+ and La3+ demonstrate efficiencies surpassing those obtained with optimized cationic DOTAP-based systems, while preserving the viability of cells. Inspired by bacteriophages that resort to polycations to compact their genetic materials, complexes assembled with tetravalent spermine achieve unprecedented transfection efficiencies for phospholipids. Influence of complex growth time, lipid/DNA mass ratio, and ion concentration are examined. These complexes may initiate new developments for nontoxic gene delivery and fundamental studies of biological self-assembly.

Polymeric films containing titania nanoparticles have potential as dielectric films for flexible electronic applications. For this purpose, the nanoparticles must be homogeneously distributed. Self-assembly is emerging as a neat, elegant method for fabricating such nanostructured hybrid materials with well-distributed nanoparticles. In this work, we report a micellar solution approach for the assembly of copolymer-titanium precursor nanostructures in which titania nanoparticles were synthesized. The ratio of the amount of titanium precursor, titanium isopropoxide, to the blocks forming the micellar core, poly(4-vinylpyridine), was found to play a key role in controlling film morphology. A sphere-to-ribbon transition was observed when the amount of titanium isopropoxide was increased. The thin film morphology can be tuned using the precursor-copolymer interaction rather than just the polymer-polymer interaction or the polymer-solution interaction. This method provides yet another way to control the morphology of nanostructures.

Poly(vinyl pyrrolidone) (PVP) was grafted onto Pluronic F127 (PEO-PPO-PEO) to produce novel amphiphilic PVP-g-F127 graft copolymers. A controlled synthesis method was used to graft PVP onto different parts of F127. Two types of graft polymers were obtained: one has PVP grafted onto the PEO part of F127 and the other has PVP grafted onto the PPO part of F127. The association behavior of the two modified polymers was examined using differential scanning calorimetry, surface tension measurements, and dynamic light scattering.

Pulmonary arterial hypertension (PAH) in patients with systemic lupus erythematosus (SLE) is uncommon but is associated with poor survival. This study aimed to examine the long-term effects of bosentan, a dual endothelin-1 receptor antagonist, on symptomatology, haemodynamics and quality of life measures in SLE patients with symptomatic PAH. Four local patients had been followed up prospectively with pre-defined protocol during 12-months of bosentan treatment. Six minute walk distance (6MWD), NYHA functional class, Borg Dyspnoea Index (BDI) and SF-36 were measured at 0, 3, 6, 9 and 12 months. Systolic pulmonary arterial pressure (PAP) was measured by transthoracic echocardiography at zero, six and 12 months. Clinical parameters were analysed, pooling data from other SLE patients reported in the literature (n = 4). Bosentan was found to result in significant improvement in 6MWD compared to baseline [+24.8 m, +26.2 m, +54 m and +62.7 m at three (P = 0.001), six (P = 0.001), nine (P = 0.24) and 12 (P = 0.01) months respectively]. A differential effect was found with greater response in patients with lower exercise capacity. This was accompanied by decrease in NYHA functional class, BDI, transient or sustained drop in systolic PAP and mild improvement in SF-36 domains including mental health, vitality, social function and general health. Significantly deranged liver function was found in one patient.

Surface tension (ST) measurements were carried out on various binary mixtures of the "normal" surfactants, such as nonionic surfactant, hexaethylene glycol mono-n-dodecyl ether(C12EO6), and cationic surfactant, tetradecyltrimethylammonium bromide (TTAB), and polymeric copolymer, Pluronic F127, F127(PPO)-g-PVP, and F127(PEO)-g-PVP. In all cases mixed micellar aggregates were formed and critical micellar concentrations of binary mixtures containing different mole fractions of the surfactants were measured using surface tension measurement. In the region where mixed micelles are formed, the interaction of two "normal" surfactants and three "polymeric" nonionic surfactants showed synergistic behavior and the results were analyzed using a interaction parameter, beta, which characterized the interaction in the mixed micelle and introduced by a regular solution theory. The regular solution theory can be applied to describe the interaction between TTAB and C12EO6, and graft polymeric surfactants systems. The results discussed in this paper indicated that regular solution theory has broader extent of application.

Morphologies of surface micelles of the diblock copolymer polystyrene-block-poly(4-vinylpyridine) (PS-P4VP) at different concentrations were investigated using TEM. Highly-ordered spherical micelles were observed. The morphology was found to depend strongly on the solution concentration. A transformation from spherical to cylindrical micelles and the formation of multilayers of micelles were observed when the concentration was increased. The evolution of the morphology of the diblock copolymer film cast on Si substrates in the presence of different solvents was also investigated using AFM. We find that there is a discrepancy in the structure obtained using TEM and AFM because of the presence of a selective solvent in the TEM sample. The transformation from cylindrical to spherical micelles was observed for the film prepared under a nitrogen atmosphere. Hexagonally ordered holes were observed in the film prepared in air. The presence of moisture in the air may play an important role in the formation of this structure.

A 78-year-old woman was admitted to hospital with central chest pain and the electrocardiographic and cardiac marker changes typical of acute anterior myocardial infarction. Coronary angiography revealed normal epicardial coronary arteries, and left ventriculography showed apical akinesis as well as basal hyperkinesis. This is a case of transient left ventricular apical ballooning or takotsubo cardiomyopathy, possibly attributable to catecholamine-mediated myocardial stunning.

The ability to control the structure and function of supramolecular self-assemblies gives rise to many patterning possibilities. Making use of the interactions between the copolymers and solvent provides a neat way of controlling the structures. The pyridine residues of each of the diblock copolymer polystyrene-b-poly(4-vinylpyridine) (PS-P4VP) was selectively betainized using 1,3-propane sultone under mild conditions to yield a series of novel betaine diblock copolymers in chloroform and toluene, respectively. The solution properties were studied using dynamic light scattering, static light scattering, and (1)H NMR spectroscopy. The morphology of the resulting micellar film was studied using transmission electron microscopy. The size of the micelles formed was found to be strongly dependent on the amount of sultone grafted and the shape of PS-P4VP-sultone micelle changed from spherical to elongated with different PS-P4VP-to-sultone ratio.