Arthritis of leprosy

An inflammatory polyarthritis has been previously described in leprosy but accounts of the clinical characteristics have varied. All patients with joint symptoms admitted to a leprosy centre over 5 months were examined by a rheumatologist. Of 48 acute admissions, 20 (42%) had a symmetrical polyarthritis affecting the wrists and fingers. This was strikingly similar to RA in appearance. The arthritis occurred exclusively in patients with reactions mainly during anti-mycobacterial treatment. The clinical features of the joint disorder were identical in Type I (associated with alterations in immune status) and Type II (erythema nodosum leprosum) reactions. Synovial tissue from one patient revealed no mycobacteria. Four of five hand X-rays suggested small erosions of the finger joints

Carotid plaque vulnerability assessment by microscopic morphology analysis, ultrasound and 3D model reconstruction

Research suggests that plaque morphology plays a crucial role in determining plaque vulnerability. However the relationship between plaque morphology and rupture is still not clearly understood due to the limited information of plaque morphology. The aim of this study is to improve our understanding of the relationship between plaque morphology and rupture, and to use this to predict the risk of plaque rupture from the morphology at the molecular level. This can enable the identification of culprit lesions in clinical situations for assessing plaque rupture risk. Histological assessments were carried out on 18 carotid plaque specimens. The 3-D collagen, lipid and macrophage distributions along the entire length of the plaque were analysed in both ruptured and non-ruptured symptomatic plaques. In addition, plaque morphology on the rupture sites were examined and compared with the surrounding regions. It was found that ruptured plaques had thinner fibrous caps and larger lipid cores compared to non-ruptured plaques. Also, ruptured plaques had lower collagen content compared to non-ruptured plaques, and higher collagen contents upstream compared to downstream region from the plaque throat. At the rupture site there was lower collagen content, and a larger lipid core thickness behind a thin fibrous cap compared with the mean for the longitudinally adjacent and circumferential regions. Macrophage cells were located nearer to the boundary of the luminal wall in ruptured plaques. For both groups, the area occupied by macrophages is greater at the upstream shoulder of the plaque. There is a positive correlation between macrophage area and lipid core area, a negative correlation between macrophage area and collagen content, and between lipid core size and collagen content for both plaque groups. 3D reconstruction of ex-vivo specimens of carotid plaques were carried out by a combined analysis of US imaging and histology. To reconstruct accurate 3D plaque morphology, the non-linear tissue distortion in histological images caused by specimen preparation was corrected by a finite element (FE) based deformable registration procedure. This study shows that it is possible to generate a 3D patient specific plaque model using this method. In addition, the study also quantitatively assesses the tissue distortion caused by histological procedures. It shows that at least 30% tissue shrinkage is expected for plaque tissues. The histology analysis result was also used to evaluate ultrasound (US) tissue characterization accuracy. An ex-vivo 2D ultrasound scan set-up was used to obtain serial transverse images through an atherosclerotic plaque. The different plaque component region obtained from ultrasound images was compared with the associated histology result and photograph of the sections. Plaque tissue characterisation using ex-vivo US can be performed qualitatively, whereas lipid core assessment from ultrasound scan can be semi-quantitative. This finding combined with the negative correlation between lipid core size and collagen content, suggests the ability of US to indirectly quantify plaque collagen content. This study may serve as a platform for future studies on improving ultrasound tissue characterization, and may also potentially be used in risk assessment of plaque rupture.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Lithium-Ion Supercapacitor Using Vertically-Aligned Carbon Nanotubes From Direct Growth Technique, And Its Electrochemical Characteristics

This paper reports the fabrication of a lithium ion supercapacitor from vertically-aligned carbon nanotubes (VACNTs) directly grown on a conductive substrate (SUS 310S alloy), using alcohol catalytic chemical vapour deposition technique. CNTs direct growth technique on an electrically conducting foil simplifies the electrode assembly, thus reducing the fabrication process, because the foil can directly act as a current collector. With the VACNT direct growth technique, the supercapacitor electrode was easily prepared and assembled with a non-aqueous 1 M LiPF6 electrolyte. Experimental results show that CNTs (multi-walled type structures of good quality) were perpendicularly grown to the substrate. This device demonstrates a specific capacitance of up to 101 F g-1 (at a scan rate of 1 mVs-1), and a high-rate capability, up to a scan rate of 1000 mVs-1. The VACNT electrode electrochemical performance was also measured by galvanostatic charge-discharge and electrochemical impedance spectroscopy. The effect of free standing CNTs direct growth on the current collector makes insulating binder material unnecessary, thus producing better ion accessibilities to its surface. This also contributes to the good and reliable electrochemical supercapacitor performance

Effect of Dodecylbenzene Sulfonic Acid Dopant Concentrations on the Synthesis of Polyaniline

Modified physicochemical properties of polyaniline (PANI) colloids in response to various polymerization conditions are being made to enhance the electrical conductivity of PANI that can be used in supercapacitor purpose. In this paper, an attempt has been made to improve the mechanical stability of PANI by synthesizing with different concentrations (0.8, 1.65, 2.0, and 2.5 mmol) of dodecylbenzenesulfonic acid (DBSA). The DBSA doped PANI colloids were characterized by using XRD, Raman spectra and SEM. PANI containing 2.0 mmol of DBSA has the highest percentage of crystallinity (Xc %) as analyzed from XRD spectrum. Scanning electron microscopy (SEM) has been used to investigate the influence of the feed concentration of DBSA on the morphology of the polymer.  A detailed study on the  Raman spectroscopies of PANI-DBSA colloids has been carried out  which shows that intensity of RAMAN spectra are directly proportional to the increased crystallized region of doped PANI samples; higher intensity may attribute due to the large change in polarization associated with the formation of covalent bond in PANI

Effect of Dodecylbenzene Sulfonic Acid Dopant Concentrations on the Synthesis of Polyaniline

Modified physicochemical properties of polyaniline (PANI) colloids in response to various polymerization conditions are being made to enhance the electrical conductivity of PANI that can be used in supercapacitor purpose. In this paper, an attempt has been made to improve the mechanical stability of PANI by synthesizing with different concentrations (0.8, 1.65, 2.0, and 2.5 mmol) of dodecylbenzenesulfonic acid (DBSA). The DBSA doped PANI colloids were characterized by using XRD, Raman spectra and SEM. PANI containing 2.0 mmol of DBSA has the highest percentage of crystallinity (Xc %) as analyzed from XRD spectrum. Scanning electron microscopy (SEM) has been used to investigate the influence of the feed concentration of DBSA on the morphology of the polymer.  A detailed study on the  Raman spectroscopies of PANI-DBSA colloids has been carried out  which shows that intensity of RAMAN spectra are directly proportional to the increased crystallized region of doped PANI samples; higher intensity may attribute due to the large change in polarization associated with the formation of covalent bond in PANI

EFFECTS OF FILLER HYBRIDIZATION ON THE MECHANICAL PROPERTIES OF NR/SBR/EPDM RUBBER BLENDS

Hybridization of active fillers is one of the techniques utilized to enhance rubber properties. This study highlights the effects of filler hybridization on the mechanical properties of an industrial applied natural rubber/styrene butadiene rubber/ethylene propylene diene terpolymer (NR/SBR/EPDM) Rubber Mat compound reinforced by non-black fillers. Initially, three different rubber compounds were prepared; i) calcium carbonate (CaCO3)-filled NR [CaCO3NR] as reference sample, ii) precipitated silica (PSi)-filled NR/SBR/EPDM [PSiBR], and iii) calcined clay (ClCy)-filled NR/SBR/EPDM [ClCyBR]. From these compounds, composites of NR/SBR/EPDM were prepared. The ratio of PSi:ClCy was varied to study the effects of filler hybridization. CaCO3 was added for cost advantage industrially and its level was fixed. It was found that inclusions of ClCy and PSi individually and their hybridizations show higher tensile and tear strengths than the reference sample. Particularly, the largest improvement was found with the amount of ClCy which is higher than PSi. A ratio of PSi:ClCy in this particular range (1:2 to 2:3), seems to provide the optimum packing factor for good interaction between the fillers. SEM analysis suggests that better dispersion and packing of fillers due to size and shape of hybrid fillers play an important role in improving the composite properties

Physio-genetic behavior of maize seedlings at water deficit conditions. Cercetari Agronomice in Moldova 146

ABSTRACT. Drought stress is limiting global crop production more seriously than ever because of rapid change in global climate. Present investigations were made with a view to understand the traits which can be used as selection criteria for drought tolerance in maize at seedling stage. For this purpose twenty-five maize inbred lines were evaluated under water deficit conditions for traits like fresh shoot weight, fresh shoot length, fresh root length, fresh root weight, leaf venation, stomatal frequency and epidermal cell size. Significant differences were found among the genotypes for various physio-genetic traits. The genotypes 20P2-1, L5-1, 150P2-1, 70NO2-2, 150P1 and L7-2 were found good performer and may be exploited for developing drought tolerant synthetics and hybrids. Fresh shoot length and fresh root weight found overall direct and indirect contributor in fresh shoot weight and they were positive and significantly correlated with fresh shoot weight. Stomatal frequency and epidermal cell size had significantly decreasing direct and indirect effects on fresh shoot weight and significant genetic correlation with it. These results suggested that fresh shoot length and fresh root weight (Increased) stomatal frequency and epidermal cell size (decreased) might be used as selection criterion while selection for high fresh shoot yield under drought conditions