Electrically conductive and high temperature resistant superhydrophobic composite films from colloidal graphite

Electrically conductive and self-cleaning superhydrophobic films (water contact angles >160°, droplet roll off angles <5°) were fabricated by simply solution casting sub-micron polytetrafluoroethylene (Teflon) particle dispersed alcohol-based colloidal graphite solutions. The process is very suitable for forming conductive superhydrophobic coatings on glasses, metals, ceramics and high performance polymers such as polyimide (Kapton®). The solutions were deposited on microscope glass slides and Kapton® films by drop casting. After solvent evaporation under ambient conditions, the coatings were annealed to melt Teflon. Upon melting, Teflon particles fused into one another forming a hydrophobic polymer matrix. The degree of superhydrophobicity and the surface morphology of the coatings together with their electrical conductivity were studied in detail by varying Teflon-to-graphite weight fractions. A number of applications can be envisioned for these coatings such as electrode materials for energy conversion devices, high performance electromagnetic shielding materials, flexible electronic components and heat exchanger surfaces, to name a few

Clinical and Experimental Projects on Chemotherapy of Bladder Tumours

Our clinical and experimental experience with chemotherapy of bladder tumours is reviewed. The routes of drug administrations, drug dosages and combinations, are presented. Adjuvant radiotherapy and chemoprophylaxis of certain tumours are discussed.S. Afr. Med. J., 48, 631 (1974

Clinical and experimental projects on chemotherapy of bladder tumours

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Patients with chronic migraine without history of medication overuse are characterized by a peculiar white matter fiber bundle profile

Background: We investigated intracerebral fiber bundles using a tract-based spatial statistics (TBSS) analysis of diffusion tensor imaging (DTI) data to verify microstructural integrity in patients with episodic (MO) and chronic migraine (CM). Methods: We performed DTI in 19 patients with MO within interictal periods, 18 patients with CM without any history of drug abuse, and 18 healthy controls (HCs) using a 3 T magnetic resonance imaging scanner. We calculated diffusion metrics, including fractional anisotropy (FA), axial diffusion (AD), radial diffusion (RD), and mean diffusion (MD). Results: TBSS revealed no significant differences in the FA, MD, RD, and AD maps between the MO and HC groups. In comparison to the HC group, the CM group exhibited widespread increased RD (bilateral superior [SCR] and posterior corona radiata [PCR], bilateral genu of the corpus callosum [CC], bilateral posterior limb of internal capsule [IC], bilateral superior longitudinal fasciculus [LF]) and MD values (tracts of the right SCR and PCR, right superior LF, and right splenium of the CC). In comparison to the MO group, the CM group showed decreased FA (bilateral SCR and PCR, bilateral body of CC, right superior LF, right forceps minor) and increased MD values (bilateral SCR and right PCR, right body of CC, right superior LF, right splenium of CC, and right posterior limb of IC). Conclusion: Our results suggest that chronic migraine can be associated with the widespread disruption of normal white matter integrity in the brain

Ownership and control in a competitive industry

We study a differentiated product market in which an investor initially owns a controlling stake in one of two competing firms and may acquire a non-controlling or a controlling stake in a competitor, either directly using her own assets, or indirectly via the controlled firm. While industry profits are maximized within a symmetric two product monopoly, the investor attains this only in exceptional cases. Instead, she sometimes acquires a noncontrolling stake. Or she invests asymmetrically rather than pursuing a full takeover if she acquires a controlling one. Generally, she invests indirectly if she only wants to affect the product market outcome, and directly if acquiring shares is profitable per se. --differentiated products,separation of ownership and control,private benefits of control

Localization of AQP5 during development of the mouse submandibular salivary gland

Aquaporin 5 (AQP5) is known to be central for salivary fluid secretion. A study of the temporal-spatial distribution of AQP5 during submandibular gland (SMG) development and in adult tissues might offer further clues to its unknown role during development. In the present work, SMGs from embryonic day (E) 14.5–18.5 and postnatal days (P) 0, 2, 5, 25, and 60 were immunostained for AQP5 and analyzed using light microscopy. Additional confocal and transmission electron microscopy were performed on P60 glands. Our results show that AQP5 expression first occurs in a scattered pattern in the late canalicular stage and becomes more prominent and organized in the terminal tubuli/pro-acinar cells towards birth. Additional apical membrane staining in the entire intralobular duct is found just prior to birth. During postnatal development, AQP5 is expressed in both the luminal and lateral membrane of pro-acinar/acinar cells. AQP5 is also detected in the basal membrane of acinar cells at P25 and P60. In the intercalated ducts at P60, the male glands show apical staining in the entire segment, while only the proximal region is positive in the female glands. These results demonstrate an evolving distribution of AQP5 during pre- and postnatal development in the mouse SMGs

Mutant TDP-43 and FUS Cause Age-Dependent Paralysis and Neurodegeneration in C. elegans

Mutations in the DNA/RNA binding proteins TDP-43 and FUS are associated with Amyotrophic Lateral Sclerosis and Frontotemporal Lobar Degeneration. Intracellular accumulations of wild type TDP-43 and FUS are observed in a growing number of late-onset diseases suggesting that TDP-43 and FUS proteinopathies may contribute to multiple neurodegenerative diseases. To better understand the mechanisms of TDP-43 and FUS toxicity we have created transgenic Caenorhabditis elegans strains that express full-length, untagged human TDP-43 and FUS in the worm's GABAergic motor neurons. Transgenic worms expressing mutant TDP-43 and FUS display adult-onset, age-dependent loss of motility, progressive paralysis and neuronal degeneration that is distinct from wild type alleles. Additionally, mutant TDP-43 and FUS proteins are highly insoluble while wild type proteins remain soluble suggesting that protein misfolding may contribute to toxicity. Populations of mutant TDP-43 and FUS transgenics grown on solid media become paralyzed over 7 to 12 days. We have developed a liquid culture assay where the paralysis phenotype evolves over several hours. We introduce C. elegans transgenics for mutant TDP-43 and FUS motor neuron toxicity that may be used for rapid genetic and pharmacological suppressor screening

Anodic deposition of compact, freely-standing or microporous polypyrrole films from aqueous methanesulphonic acid

Freely-standing and flexible films (0.075 to 9 mm in thickness) of electrically conducting polypyrrole were synthesised via anodic electrodeposition onto a stainless steel substrate from methanesulphonic acid under stirred conditions at 295 K. Cyclic voltammetry was used to studythe effect of pyrrole monomer concentration (0.01 to 1.0 mol dm-3) and methanesulphonic acid level (1.0 to 6.0 mol dm-3) on the formation of polypyrrole films. The films were prepared for deposition times of 30–240 s at constant current densities of 1 to 15 mA cm-2. The ionic conductivity of freely-standing polypyrrole membranes in aqueous methanesulphonic acid was studied. Scanning electron microscopy was used to image the surface microstructure. The polypyrrole films, which were prepared in the oxidised (methanesulphonate doped), conductivestate, showed an ionic area resistance as low as 10 ohm cm2. The films were readily doped with the methanesulphonate anion and the membrane ionic conductivity was dependent on the electrolyte composition used for their deposition. In the presence of anodic oxygen evolution, thefilms showed a ‘template-free’ porosity due to film growth around the bubbles

The swimmer's otitis. An up to date and prevention options

The swimmer’s otitis or acute otitis externa, is a pathology that often occurs in those who practice swimming at a competitive level. The same problem often occurs in the summer with the attendance of swimming pools and bathing areas. A survey made in the United States in 2007 confirms the dynamics of the onset of this pathology, because the contamination of fungi and bacteria in the waters of the swimming pools and the sea cause the inflammation of the epithelium of the auditory canal. To face this issue, in addition to a correct diagnosis, and the necessary and appropriate therapies, it may follow the use of these medicinal preparations. The first one (A) is protective-acting, the second one (B) is characterized as a preventive, hygroscopic, moistening, antiseptic and antimycotic-acting solution. Swimmers who have been using the two (pre-and post) preparations daily for about a year have reported sporadic episodes of otitis. However, there is no doubt that these two compounds deserve a meticulous clinical trial in order to confirm their preventive and therapeutic potentials in external acute otitis