Phenolic Compounds as Cultivar- and Variety-distinguishing Factors in Some Plant Products

The aim of the study was to determine whether phenolic compounds in some varieties of buckwheat, winter and spring barley and peas can be used as factors which distinguish selected cultivars and varieties of plant material. It was observed that the content of total phenolics might be useful as a cultivar-distinguishing factor for all the plant materials analyzed, but it was a distinguishing factor for only some varieties. Individual cultivars and varieties were best distinguished by the content of syringic acid. The levels of syringic and vanillic acids were in reverse proportion to the total amount of phenolics soluble in methanol and a positive correlation between syringic and ferulic acid was observed. Moreover, the protein content of plant material was analyzed and a significant (p ≤ 0.05) correlation between this component and ferulic and vanillic acids was noted.     

Effects of Roll Gap,Kernel Shape,and Moisture on Wheat Breakage Modeled Using the Double Normalized Kumaraswamy Breakage Function

Flour milling separates endosperm from bran through repeated roller milling and sifting, in which the size distribution of particles produced by the initial breakage of the wheat kernels critically affects the process. The double normalized Kumaraswamy breakage function (DNKBF), previously developed to describe wheat breakage during roller milling, was extended to refine the modeling of the effect of roll gap on breakage. The DNKBF describes two populations of particles arising from roller milling of wheat, a narrow peak of mid‐sized particles and a wider distribution of both small and very large particles. A new dataset was obtained from milling a set of wheat samples bred to give a range of shapes by cross‐breeding a conventional wheat, Cappelle, with an almost spherical wheat, Triticum sphaerococcum. A residual analysis showed a statistically significant effect of kernel shape on breakage using this new dataset. This analysis supports earlier suggestions that more elongated kernels break to give slightly larger particles than more spherical kernels of equivalent hardness, because of the relatively greater bran content of elongated kernels. The extended DNKBF was also used to model effects of moisture content, showing a distinct disjunction at around 16% moisture that aligns with commercial practice for wheat milling.     

Experimental micromechanical characterisation of wood cell walls

The properties of wood and wood-based materials are strongly dependent on the properties of the fibres, that is, the cell wall properties. It is thus highly important to be able to mechanically characterise cell walls in order to understand structure–property relationships. This article gives a brief overview of the state of the art in experimental techniques to characterise the mechanical properties of wood at both the level of the single cell and that of the cell wall. Challenges, opportunities, drawbacks and limitations of single fibre tensile tests and nanoindentation are discussed with respect to the wood material properties.     

Reversible switching of hydrogel-actuated nanostructures into complex micropatterns

Responsive behavior, which is intrinsic to natural systems, is becoming a key requirement for advanced artificial materials and devices, presenting a substantial scientific and engineering challenge. We designed dynamic actuation systems by integrating high-aspect-ratio silicon nanocolumns, either free-standing or substrate-attached, with a hydrogel layer. The nanocolumns were put in motion by the "muscle" of the hydrogel, which swells or contracts depending on the humidity level. This actuation resulted in a fast reversible reorientation of the nanocolumns from tilted to perpendicular to the surface. By further controlling the stress field in the hydrogel, the formation of a variety of elaborate reversibly actuated micropatterns was demonstrated. The mechanics of the actuation process have been assessed. Dynamic control over the movement and orientation of surface nanofeatures at the micron and submicron scales may have exciting applications in actuators, microfluidics, or responsive materials.     

Response of balsam fir and hemlock roots to injuries

Drill wounds in balsam fir and hemlock roots activated the nonspecific resistance mechanisms of compartmentalization in wood and necrophylactic periderm in bark. Tangential bands of resin ducts localized around the wounds constituted the barrier zones in the secondary xylem of conifer roots. Barrier zones were more extensive in roots which showed symptoms characteristic of invasion by fungi and bacteria after wounding. This observation supports an expanded definition of barrier zones; barrier zones may form not only in response to mechanical wounds but also in response to xylem injury caused by pathogens. Multiple bands of resin ducts were common in young xylem when bark lesions developed around wounds. Necrophylactic periderms isolared dead bark from living bark. Development of phellem cells with dark contents and thick suberized walls, typical of exophylactic periderm, followed initiation of necrophylactic periderm. The wound responses were similar in both balsam fir and hemlock.     

Lasers in the surgical treatment of canine prostatic neoplasia and selected tumours of the male reproductive system

Light-based technologies are applied in various fields of medicine: for example optical diagnostics, light-activated therapy and surgery. Although light-based surgical procedures had hardly been a novelty, the revolutionizing moment for surgery came with the first use of light to cut tissue. Nowadays, surgical lasers are routinely used across numerous medical specialties, including gynaecology and urology. They are a part of the surgical treatment of benign prostatic hyperplasia, prostate carcinoma, penis carcinoma, genital skin lesions and orchidectomy. While in human urology lasers continue to establish their position as one of the standard surgical tools, veterinary patients are rarely treated with what here is still considered a technical innovation. However, through research on laser treatment of the prostate hyperplasia conducted on a canine model, veterinary medicine has gained a massive portion of data. It may prove beneficial for our clinical patients. In this review, we introduce the very principles of laser surgery as well as its current and future applications in oncologic surgery of the canine prostate gland and the male reproductive system.