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The aim of this work was to investigate the influence of nanocellulose on the storage stability and rheological properties of urea formaldehyde (UF)-based adhesive compositions for wood-based panels. Three types of UF resins characterized by different F/U molar ratios were used for this research. Resin modifications with nanocrystalline cellulose and a nanofibrillated cellulose content of 1.0% to 5.0% by dry weight of resin were prepared. The flow curve characteristics and storage stability were studied. The viscosity values mainly depended upon the type of nanocellulose used, as well as its loading in the composition. The UF resins modified with nanocrystalline cellulose kept their rheological behavior and proper viscosity after 4 weeks in storage, which lowered the percentage of viscosity retention by approximately 1.5 times compared with that of industrial resins. Nanocrystalline cellulose might be used as a stabilizer in resin compositions during long-term storage, while nanofibrillated cellulose might act as a thickening agent through the limited extent of loading in a composition. [ABSTRACT FROM AUTHOR]

The low economical valorisation of wood products from coppices and from high forest logging residues is a problem that requires to be addressed. In order to support forest owners a greater product diversification is required. To reach this goal, wood charcoal could be rediscovered in order to improve forest value chain. Charcoal production with the use of new models of mobile charcoal kiln were tested evaluating the characteristics of the process and the product. This process could be very advantageous for the local community, differentiating economically marginal productions and qualifying new operators. The focus in this regard also falls on the need to produce charcoal at the landing sites, thus considerably reducing transport costs. The possibility of producing charcoal directly at the landing sites could make the overall economic chain consistently more valuable. Wood charcoal is an activated charcoal, due to the mode of production, whose activation increases if crushed or pulverized. Due to the high specific area the activated carbon has high adsorbent capacities. The product charcoal, even if it is unjustly considered as "poor" (quality), has remarkable qualities that make it interesting in other aspects. In fact, the uses of charcoal are extensive and encompass numerous fields: apart from the traditional use, this product is used in industrial waste water treatment (water purification, air filtration), food industry (for decolorization and deodorization of wine, vinegar, fruit juices and alimentary use), herbal, pharmaceutical and cosmetic industries, textile sector and in agriculture (as a soil improver called "Biochar"). Biochar is a biomaterial which can be produced starting from several different feedstocks. Just for example, our research group, in the framework of different projects and international collaborations, has been producing biochar from beech firewood, pine wood chips, poplar wood chips, chestnut pruning as well as from the lignocellulosic residues of wood liquefaction process. Given the increasing interest around this product, nowadays, several studies aimed at characterization are in progress, trying to identify the best woody residues from which to produce small-scale charcoal for different purposes. Moreover, its properties seem to open new frontiers continuously. Charcoal produced in forest chains could also appeals to the certification of Chain of Custody of PEFC reaching a more qualified market, both for products and for process of sustainable productions. In this regard will be important to respect the basic principles of Circular Economy and Green Economy. [ABSTRACT FROM AUTHOR]

The valorization of lignocellulosic biomass for the manufacturing of value-added materials is a fundamental pillar of sustainable development and circular economy, providing an alternative to petroleum-based refineries and contributing to green transition in production. Lignocellulosic biomass is a valuable source of components and can be utilized to produce biopolymers via chemical, physical, microbiological, or enzymatic routes. Fractions obtained from the lignocellulosic biomass can be used in suitable and specific applications. Currently and primarily, wood is a raw source of nanocellulose production. In the interest of the diminishing wood resources in the world, the nanocellulose can be extracted from the lignocellulosic biomass, including waste biomass. In turn, liquefaction can be adopted as one of the effective methods of lignocellulosic waste management. The presented study focused on the different aspects of synthesis, modification, and applications of biopolymers obtained from lignocellulosic biomass, such as nanocrystalline cellulose (CNC), nanofibrillated cellulose (CNF), and liquefied wood. The research aimed to valorize the lignocellulosic biomass for the production of biopolymers intended to use in adhesives and wood composite materials. Firstly, the potential of lignocellulosic biomass to form biopolymers was discussed. Furthermore, different methods for biomass pre-treatment were explained. The need for nanocellulose modification was highlighted to improve the functionality of the materials. Finally, the application of both kinds of nanocellulose and liquefied wood were explored in the field of the wood-based panel sector. Nanocellulose was effectively recovered, and liquefied wood was successfully obtained from lignocellulosic biomass, which was confirmed by microscopic examination. Nanocellulose acted as modifying and reinforcing agent of amine resins improving mechanical performance and reducing formaldehyde emission. On the other hand, replacing 40% of the standard amino resin with liquefied wood caused that the minimum requirements for particleboards of type P2 according to PN-EN 312 has been met. [ABSTRACT FROM AUTHOR]

Meibomian gland dysfunction is a common ocular disorder affecting from 39 to 50% of population. Despite that, so far a pathophysiology path of the disease remains unknown, moreover there is no distinct border between physiology and the disease. There has been no clear diagnostic criteria. The purpose of this review was to combine a current knowledge of Meibomian gland anatomy, Meibomian gland dysfunction epidemiology, as well as presenting current definition, nomenclature, classification and diagnostic criteria. The importance of diagnosis associated with conditions such as aqueous tear deficiency, seborrheic dermatitis, and rosacea is emphasized. The available treatment methods are discussed. Meibomian gland dysfunction, blepharitis, dry eye syndrome.

Purpose: To analyze genotype-phenotype correlation in patients originating from Polish population with the transforming growth factor beta induced (TGFBI) corneal dystrophies., Methods: Sixty affected and 31 unaffected individuals from 15 unrelated Polish families were included in the study. The clinical diagnosis was based on the slit-lamp exam, 1310 nm time domain and 1310 nm swept source spectral domain optical coherence tomography (OCT). Histopathologic analysis was performed on 10 available corneal buttons. Exons of the TGFBI gene were screened for mutations with polymerase chain reaction (PCR) and direct DNA sequencing., Results: We found the lattice phenotype dominant compared to the granular one in the Polish population (41:16 patients; lattice:granular). We identified five distinct mutations responsible for TGFBI corneal dystrophies (R124R, R124H, R555W, R555Q, and H626R). There was a strong genotype-phenotype correlation in the case of R124R and R555W mutations, while there was a distinct phenotypic heterogeneity in the case of the H626R mutation. OCT analysis revealed that the reflectivity, location and pattern of the corneal deposits were different among the TGFBI corneal dystrophies. The advantage of spectral swept source OCT over time-domain OCT scans is a more distinct visualization of the Bowman's layer area and deposits located under the epithelium., Conclusions: This study underlines the role of comprehensive phenotype-genotype analysis in TGFBI corneal dystrophies, describes for the first time the TGFBI mutation spectrum in a Polish population and reveals phenotypic heterogeneity in the case of the H626R mutation.

Purpose: To present the results of deep anterior lamellar keratoplasty (DALK) using "big bubble" technique, performed from 2006 to 2008 in Ophthalmology Department, District Railway Hospital in Katowice., Material and Methods: 53 patients (53 eyes) underwent DALK using "big bubble" technique due to keratoconus, corneal dystrophies and postinflammatory corneal opacification with continue Descemet's membrane and healthy endothelium. Best corrected visual acuity, main astigmatism, central corneal thickness, endothelium cell density, intra- and postoperative complications were assessed., Results: Mean follow up 15.4 months ranged from 11 to 24 months. Averaged best corrected visual acuity averaged equaled 0.6 and ranged from 0.1 to 4.0, mean astigmatism 2.6 D, ranged from 1.0 D to 2.6 D. Mean central corneal thickness was 503.4 microm and ranged from 379 microm to 694 microm, mean endothelium cell density before surgery equaled 2895/ mm2 and postoperatively 2398/ mm2. Incomplete Descemet's membrane detachment was diagnosed in 3 cases, intraoperative microperforations in 5 eyes and conversion to penetrating keratoplasty was needed in 4 patients. Postoperative disc opacity in 3 cases, increase of intraocular preassures in 1 case and early postoperative Descemet's membrane detachment in 1 eye. Posterior cataract formation in 4 eyes and in 1 case permanent mydriasis (Urrets-Zavalia Syndrome), was observed. There was no graft rejection observed., Conclusions: Although technically more demanding lamellar keratoplasty, could be considered as an alternative "gold standard" penetrating keratoplasty.

Purpose: To present the results of endothelial keratoplasty (DSEK) using "Busin" technique performed from September 2008 to December 2008 in Ophthalmology Department, District Railway Hospital in Katowice., Material and Methods: 7 patients (7 eyes) underwent DSEK using "Busin glide" technique, due to the corneal edema after cataract phacoemulsification. Best corrected visual acuity, central corneal thickness, endothelium cell density were assessed three and six month postoperatively., Results: Mean time period between cataract surgery to DSEK was 15.8 month (from 11 to 37 months). The mean central corneal thickness before surgery was 750 microm (from 690 microm to 850 microm), mean best corrected visual acuity 0.001 (from light perception to 0.01). The average best corrected visual acuity three months after surgery was 0.4 (0.1 to 0.6), and 0.5 (from 0.1 to 0.7), six months. Mean central corneal thickness 3 months postoperatively equaled 790 microm (from 714 microm to 850 microm), and a sixth month was 659 microm (from 800 microm to 604 microm). Three months after DSEK, mean endothelium cell density was 2640/mm2 (from 2301/mm2 to 2904/mm2), six months after DSEK the average endothelial cell density equaled 2430/mm2 (from 2210/mm2 to 2780/mm2). Disc dislocation was not observed in studied group., Conclusions: The use of BG as a donor lenticule insertion technique in DSEK technique seems to be a safe support of this lamellar surgery.

Purpose: Analysis of morphologic and functional outcomes of endothelial keratoplasty with descemetorhexis technique for recipient Descemet's membrane removal (DSEK)., Material and Methods: We analyzed patients treated for chronic endothelial dysfunction with DSEK technique. For the study 12 patients (12 eyes) with follow up at least 9 months, were qualified. Study group consisted of 9 women and 3 men, in age from 53 to 83 years, mean 72.9 +/- 7.82 years. All surgery were performed by one surgeon (EW). Anterior chamber was opened through 5 mm wide and 3 mm long sclero-corneal tunnel. Before descemetorhexis incision points on the endothelial side of cornea were done with radio-frequency diathermy. Descemet's membrane stripping was done with the forceps. Endothelial grafts were fixed with anterior chamber by air tamponade. We analyzed postoperative visual acuity (on Snellen's charts), corneal transparency, endothelial cell density, total central corneal thickness and endothelial button (with OCT Visante), and complications of the surgery., Results: 9 months postoperatively VA ranged from 0.1 to 0.5 (mean 0.28 +/- 0.15), BCVA ranged 0.1-0.9 (mean 0.43 +/- 0.30). Endothelial cell density ranged from 982 to 2781 cells per square millimeter (mean 1848.5 +/- 550.7). Total central corneal thickness ranged from 642 to 998 microm (mean 791.6 +/- 38.0 microm) before surgery and from 536 to 789 microm (mean 645 +/- 61.3 microm) 12 months postoperatively. Total central thickness of the endothelial graft 12 months postoperatively ranged from 42 to 163 microm (mean 89.1 +/- 38.2 microm). One penetrating keratoplasty was made for graft failure. Due to endothelial graft detachment or dislocation in anterior chamber, air tamponade was made in 5 cases with satisfactory final result. Only one case of the rejection was observed., Conclusions: Endothelial keratoplasty (DSEK) is safe and effective procedure in treatment of the endothelial cell dysfunction. Surgery supported by descemetorhrexis is easy and quick and results in smooth endothelial graft bed. The DSEK technique decreases surgery time and number of corneal graft dislocations.

Purpose: Posterior lamellar keratoplasty (PLK) in patients with pseudophakic corneal oedema., Participants and Methods: The PLK have been performed in our department since November 2004. The studied group consisted of 8 patients (7 female and 1 male), 65 to 82 years of age (mean age: 71.5 years). Visual acuity before the surgery ranged from 0.01 to fingers counting. All the patients suffered from pseudophakic corneal oedema. Endothelial keratoplasty was performed using Melles technique: a deep stromal pocket was created across the cornea through a 5-mm scleral access incision. Endothelium was prepared from whole eyeballs collected according to the EEBA guidelines. Donor disc containing healthy endothelium was folded during the implantation procedure. Average donor endothelial cell density was 2800 cells/mm2. All surgeries were performed by one surgeon (EW)., Results: In two eyes conversion to PKP was necessary. Best corrected visual acuity (BCVA) ranged from 0.4 to 1.0 (mean 0.6 +/- 0.12). Postoperative astigmatism ranged from 0.75 to 2.5 D (mean 1.8 D +/- 0.34). Postoperative endothelial cell density ranged from 1700 do 2300 cells/mm2 (mean 2200 cells/mm2 +/- 150). Mean Postoperative endothelial cell loss came to 29%., Conclusions: Posterior lamellar keratoplasty is a feasible surgery to manage corneal endothelial disorders. Automation of procedures by the use of laser preparation of donor tissue and adaptation automatic microkeratomes will increase the afterrepeating of procedures.