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Ultrahigh-speed violet laser diode based free-space optical communication beyond 25 Gbit/s

Violet laser diode (VLD) based ultrahigh-speed free-space optical (FSO) system is demonstrated for point-to-point data transmission. By directly encoding the VLD with 64-quadrature amplitude modulation discrete multi-tone (64-QAM DMT) data stream for optical wireless communication through 0.5–10 m in free space, the point-to-point VLD-based FSO link allows delivering the 64-QAM...

The Chronic Effects of Copper and Cadmium on Life History Traits Across Cladocera Species: A Meta-analysis

The effect of sublethal concentrations of heavy metals on cladoceran growth and reproduction is a cornerstone of modern ecotoxicology. However, the literature contains assays across numerous concentrations, on numerous species and genotypes, and conditions are far from consistent. We undertook a systematic review of the sublethal effects of copper and cadmium concentrations on...

High-resolution observations on enrichment processes in the sea-surface microlayer

For decades, researchers assumed that enrichment of dissolved organic matter (DOM) in the sea surface microlayer (SML) is solely controlled by changes in the DOM concentration at this uppermost thin boundary layer between the ocean and the atmosphere. We conducted high-resolution observations of fluorescent-DOM (FDOM) at 13 stations in the coastal and open Atlantic Ocean to...

Slip flow through a non-uniform channel under the influence of transverse magnetic field

This study deals with the steady laminar slip flow of an incompressible Newtonian fluid in a non-uniform permeable channel under the influence of transverse magnetic field. The reabsorption through the wall is accounted for by considering flux as a function of downstream distance. The non-linear coupled partial differential equations of motion are first transformed into a single...

The osteopontin-CD44 axis in hepatic cancer stem cells regulates IFN signaling and HCV replication

Osteopontin (OPN) is involved in cell proliferation, migration, inflammation, and tumor progression in various tissues. OPN induces stemness by interacting with CD44, but the functional relevance of OPN-mediated interferon (IFN) signaling and hepatitis C virus (HCV) replication in stem cell populations remains unclear. In this study, we investigated the effect of OPN on HCV...

World Bank pours hundreds of millions into African science

Huge grassroots initiative has founded dozens of research centres across the continent — but the hubs face an uncertain future.

Corrosion avoidance in lightweight materials for automotive applications

Due to increasing vehicle greenhouse gas emission regulations across the globe, the automotive industry is facing pressure to improving fuel economy. The key to achieving this is reducing vehicle mass and developing alternative energy vehicles, thereby reducing environmental impact. Lightweighting has become one of the most important aspects to consider in the design and...

Microdialysis and ultrasound elastography for monitoring of localized muscular reaction after pharmacological stimulation in rats

ObjectiveHalothane and caffeine are known to cause skeletal muscular contractions in vitro and have been proven to induce circumscribed metabolic reactions when injected into rat skeletal muscle. In this study 26 rats were investigated by either continuous application of calcium 160 mM or bolus injection of caffeine 160 mM or halothane 10% vol via a microdialysis probe in the...

A New Method for the Preparation of Fine-Grained SnO2 and WO3 Powders: Influence of the Crystallite Size on the Electrochemical Insertion of Li+ in SnO2 and WO3 Electrodes

We propose an unconventional method to obtain fine-grained SnO2 and WO3 powders. It uses as precursors, polymer complexes between polyethylene oxide (POE) and SnCl4 or WCl6 respectively. By pyrolysis of these complexes in the 350-550℃ temperature range, metal-oxide powders possessing small crystallite sizes are obtained. They are free from water and hydroxyl group contaminations...

Positive solutions for singular discrete boundary value problems

We study the existence of zero-convergent solutions for the second-order nonlinear difference equation Δ(anΦp(Δxn))=g(n,xn

Positive solutions of some nonlocal boundary value problems

We establish the existence of positive solutions of some m-point boundary value problems under weaker assumptions than previously employed. In particular, we do not require all the parameters occurring in the boundary conditions to be positive. Our results allow more general behaviour for the nonlinear term than being either sub- or superlinear.

Duodeno-Jejunal Varicosities Following Extrahepatic Portal Vein Thrombosis

A 31 year old man, under investigation for melena, was found at endoscopy to have varicosities at the site of a duodeno-jejunostomy which had been performed for duodenal atresia when he was three days old. Angiography revealed an occluded portal vein with an extensive collateral circulation. At laparotomy some of the collateral vessels were found to pass through the anastomotic...

Emblica Officinalis: A Novel Therapy for Acute Pancreatitis — An Experimental Study

Acute necrotising pancreatitis is associated with an unacceptably high mortality for which no satisfactory remedy exists. Emblica officinalis (E.o.) is a plant prescribed in Ayurveda, the Indian traditional system of medicine, for pancreas-related disorders. This study was carried out to evaluate the protective effect of E.o. against acute necrotising pancreatitis in dogs...

The Laboratory Diagnosis of Syphilis

Syphilis has several clinical manifestations, making laboratory testing a very important aspect of diagnosis. In North America, many unsuspected cases are discovered by laboratory testing. The etiological agent, Treponema pallidum, cannot be cultured, and there is no single optimal alternative test. Serological testing is the most frequently used approach in the laboratory...

A Multi-Agent Control Architecture for a Robotic Wheelchair

Assistant robots like robotic wheelchairs can perform an effective and valuable work in our daily lives. However, they eventually may need external help from humans in the robot environment (particularly, the driver in the case of a wheelchair) to accomplish safely and efficiently some tricky tasks for the current technology, i.e. opening a locked door, traversing a crowded area...

An Inexpensive Thick Film Furnace

The centre of any thick film teaching or research establishment is the furnace for firing the thick film pastes. These are usually large and expensive belt furnaces. This article discusses the design and manufacture of an inexpensive three zone belt furnace of moderate size, which any reasonably well equipped college, university or small manufacturer could assemble.

On boundary value problems for degenerate differential inclusions in Banach spaces

We consider the applications of the theory of condensing set-valued maps, the theory of set-valued linear operators, and the topological degree theory of the existence of mild solutions for a class of degenerate differential inclusions in a reflexive Banach space. Further, these techniques are used to obtain the solvability of general boundary value problems for a given class of...