The most efficient method of controlling diseases of economic importance in agricultural crops is breeding of resistant varieties.

The objective of the study was to determine the extent of the attack of smut of maize /Ustilago maydis/ on 22 hybrids and 4 maize standards under conditions, conducive to the spread of the pathogen. The study was conducted in the experimental fields of the Institute of Agriculture and Seed Science “Obraztsov Chiflik”, Ruse during the period 2012 - 2014. 26 germplasms of Preliminary Variety Trial N 2 (PVT) were included. Ustilago maydis is a common disease in most parts of the world, where maize is grown.

In all above-ground organs of the plant, tumors of smutty mass are formed. The pathogen attack leads to stunted growth of the host plant, reducing yield, and economic losses. The analysis of data about the new hybrids of IASS “Obraztsov Chiflik” - Ruse showed that fifteen of them were resistant. The resistance was the highest in the hybrids: St.20, Eks.12, Eks.10, Eks.23, Eks.16, Eks.2, Eks.3, Eks.4, Eks.6, Eks.9, Eks.13, Eks.17, Eks.19, Eks.20, 2 Eks.6. They may be used as sources of resistance. Susceptible were: Eks.15, Eks.11, Eks.8, Eks.24, Eks.1, Eks.5, St.7, Eks.14, Eks.18, Eks.22, Eks.25.

In real life, immediately after joint replacement, the artificial joint is actually bathed in blood instead of synovial fluid. Blood contains large molecules and cells of size ~ 5 to 20 micron suspended in plasma and considered to be a non-Newtonian (pseudoplastic) fluid with viscosity ~ 0.01 Pas at shear rates of 3000 s-1. The effect of these properties on friction is not fully understood and, so far, hardly any studies have been carried out regarding friction of metal-on-metal bearings with various clearances in the presence of lubricants such as blood or a fluid containing macromolecules such as Hyaluronic Acid (HA) which is a major component of synovial f luid, increasing its viscosity and lubricating properties. In this work, therefore, the frictional behaviour of a group of Smith and Nephew Birmingham Hip Resurfacing devices with a nominal diameter of 50mm and diametral clearances in the range ~ 80 to 300µm, in the presence of blood (clotted and whole blood), a combination of Bovine Serum (BS) with Hyaluronic Acid (HA) and Carboxymethyl Cellulose (CMC) adjusted to a range of viscosities (~0.001-0.2 Pas), and bovine serum with CMC adjusted to a similar range of viscosities have been investigated.

The results suggest that reduced clearance bearings have the potential to generate high friction especially in the presence of blood which is indeed the in vivo lubricant in the early weeks after implantation. Friction factors in higher clearance bearings were found to be lower than those of the lower clearance bearings using blood as the lubricant.

A total of 25 commercially available vascular access ports were evaluated in this study. Included were 5 different port models and n=5 ports per model. Port types were placed into separate water baths with respect to each model. Each was pressurized to 3 ATA (atmosphere absolute) in a hyperbaric pressure chamber simultaneously. Ports were investigated for escape gases in the water bath as well as for surface tension changes at the distal catheter end while under hyperbaric pressure. No escape gases or catheter surface tension changes were observable. The study concludes successful results for all ports in a hyperbaric chamber, when no f luid injection flow rate is necessary during pressurization.

Additive manufacturing technologies are increasingly used for medical purposes. However, questions are regularly raised about the accuracy of the anatomical models thus obtained. The present study compares two investigative methods that are used for assessing the degree of trueness of 3D printed replicas and presents recommendations for future analyses. The two techniques compared are optical surface scanning by structured light (OSS) and micro-computed tomography (µCT). The comparison was made by investigating an original cranial vault and its replica obtained by selective laser sintering (Eosint P 385, EOS GmbH, Krailling, Germany). OSS tests were conducted using a kolibri Cordless scanner (Fraunhofer IOF, Jena, Germany); µCT was performed with a v?tome?x 240/180 machine (phoenix?x-ray, GE, Wunstorf, Germany). The degree of trueness of the replica was assessed with an iterative closest point algorithm (Geomagic Qualify software, Version 12, Geomagic GmbH, 3D Systems, Rock Hill, USA).The replica’s deviations from the original, measured by OSS and µCT, respectively, were as follows: Homogeneous enlargement factor: 1.3% vs 1.2%; Mean shape deviation: +0.27mm (±0.15mm) vs +0.24mm (±0.23mm); Shape deviation

Dioxins are a group of chemically-related compounds that are persistent environmental pollutants and are formed as an unintentional by-product of many industrial processes involving chlorine such as waste incineration, chemical and pesticide manufacturing and pulp and paper bleaching. Some toxicity of other dioxins and chemicals like PCBs that act like dioxin are measured in relation to TCDD. However, dioxin is a general name for a large group of chemical compounds with similar structure. These compounds are made up of the number of the chlorine atoms and their positions in the dioxin molecule are what determine the toxicity of different dioxins. Dioxin is formed by burning chlorine-based chemical compounds with paper mills which use chlorine bleaching in their process and with the production of Polyvinyl Chloride (PVC) plastics and with the production of certain chlorinated chemicals. In September 1994, by the U.S, Environmental Protection Agency clearly describes dioxin as a serious public health threat. According to the EPA report, not only does there appear to be no “safe” level of exposure to dioxin, but levels of dioxin and dioxin-like chemicals have been found in the general U.S population that are at or near levels associated with adverse health effects. Dioxin was the primary toxic component of Agent Orange, which was found at Love Canal in Niagara Falls, NY and was the basis for evacuations at Times Beach, MO and Seveso, Italy. The most toxic compound is 2, 3, 7, 8 - Tetrachlorodibenzo - Para - Dioxin or TCDD.

Gravity plays a central role in vertebrate development, evolution and repair and regeneration responses. Recent studies suggest that tissue repair may in part be stimulated by mechanical loading of tissues in a process by which addition of mechanical energy leads to changes in tissue metabolism by mechanotransduction. In this paper we summarize reported research studies on how mechanotransduction can stimulate repair of tissues to enable clinicians to promote healing of chronic wounds and assist in the facilitation of production of tissue engineered products.

External energy in the form of extracorporeal shock waves, low intensity vibrations, pulsed electromagnetic waves and vacuum assisted wound healing have been used to promote healing. Results of research studies on cells and tissues suggest that mechanical loading can down-regulate inflammation, modify natural immune responses during healing and is also associated with promoting angiogenesis. Using vibrational OCT, a non destructive and non-invasive method to measure mechanical properties of tissues and implants, it is possible to evaluate the effects of mechanotransduction on repair responses. Further studies are needed to optimize the healing effects of mechanotransduction in bone, tendon, cartilage, nerve, myocardium, cardiovascular tissue, and skin.