Type P2 Research Articles

Investigating the use of maleic acid instead of urea formaldehyde resin and its effect on the single-layer particleboard properties

The aim of this research is to replace the urea formaldehyde (UF) resin with maleic acid and evaluate its effect on the physical and mechanical properties of single-layer particleboard. Industrial wood particles and maleic acid were used as the raw material and adhesive, respectively. Maleic acid was utilized at four levels of 0, 10, 20 and 30% by weight. The boards were manufactured under pressing conditions of 180 °C for 10 min. For comparison, a control sample was produced using 10% UF resin without maleic acid. The board size and target density were 450 × 450 × 16 mm and 0.7 g cm−3, respectively. The results showed that the strengths values of boards increased with increasing maleic acid content from 10 to 20 wt% and then slightly decreased. The control sample (10% UF resin) met the requirements of the European Standard for Type P1 boards. While, the boards bonded with 20 wt% maleic acid satisfied the requirements of the European Standard for Type P2 boards .The physical properties of the boards improved with increasing maleic acid content. Infrared (IR) spectral analysis confirmed the formation of ester bonds, suggesting a reaction between the carboxyl groups of maleic acid and the hydroxyl groups of the wood materials. In conclusion, 20% maleic acid content is effective in improving the physical and mechanical properties of particleboard.

Particleboard from the residues of wooden door production as a closed material cycle

The research was aimed at verifying that waste material from the production of wooden doors can be used to produce type P2 particleboard by EN 312 standards and that the interior door leaves made from it will meet the required tests. For this purpose, particleboards consisting of wood-based panel waste material were produced using MUF resins. The mechanical, physical and hygienic properties of the particleboard produced were investigated. Based on the results, it was confirmed that the boards made from both 100 % and 50 % waste met all the requirements for type-P2 particleboards. Prototype door leaves were then manufactured using boards made from 50 % waste and tested for functional properties. The door leaves for static torsional strength and resistance to vertical loads, soft and heavy impacts and strong body impacts meet the requirements for Class 1 by EN 1192, and resistance to repeated opening and closing cycles meets the requirements for Class 3 by EN 12400. The results indicate that producing the particleboards from waste from the same production line of interior door leaves does not impair the properties of the doors and the particle boards can be used to produce them. This product fits in with the idea of a circular economy and the idea itself contributes to the sustainability of production processes by managing part of the waste generated.

Na(Co,Ti)O2 Cathodes for Na-Ion Batteries: A Proper Choice

Increased attention to sodium-containing materials during the last several years is caused by the rapid development of sodium-ion batteries (NIBs), considered as a potential successor for lithium-ion batteries (LIBs) [1]. Especially layered sodium oxides have gained large interest due to their potential applicability as electrode materials (both, as cathodes and anodes). Similar to LiCoO2 in LIBs, NaCoO2 shows an immense potential as a cathode in NIBs. A partial replacement of Co by Ti in a Na(Co,Ti)O2 cathode can stabilize the crystal structure during (de)sodiation and reduce the number of phase transformations. Although the phase diagram of the Na-Co-Ti-O system has not been studied yet, existence of single-phase and multi-phase regions in dependence on the Na-content and temperature is reported in the literature [2]. Typically, layered Na,Co,Ti-oxides adopt three very close structure types P2, O3 and P3, which differ in the oxygen surrounding for Na-cations (octahedral or prismatic) and in the number of the formula units in the crystal unit cell (2 or 3). For application in Na-batteries, however, a trial-and-error approach is mostly needed to evaluate a composition with outstanding electrochemical performance.The redox activity of Co and Ti cations is usually characterized by two well-separated cell potentials. The Co-oxidation (Co2+ → Co3+ and Co3+→ Co4+) occurs mostly at potentials between 3 and 4 V vs. Na+/Na, qualifying the material as cathode while Ti4+/Ti3+ redox process takes place below 1.5 V, as common for anode materials. Based on our experimental studies of layered Na,Co,Ti-oxides with different compositions as NaCo0.5Ti0.5O2 (O3) [3], Na0.65Co0.5Ti0.5O2 (P3) [3], Na0.67Co0.33Ti0.67O2 (P2- and O3-structures) [4] and Na0.8Co0.8Ti0.2O2 (P2) [5] as well as on literature report [6], we can conclude that the most stable cycling behavior can be realized, if the composition in the initial (discharged) state contains mainly Co3+ and not Co2+. The reason for this is a first-order spin-state transition of high-spin HS-Co2+ to low-spin LS-Co3+ and back upon (de)sodiation, which is accompanied by a phase transformation, leading to a huge potential hysteresis of about 2 V. This hysteresis only slightly depends on the temperature between 0 °C and 40 °C. Among the compositions mentioned above, Na0.8Co0.8Ti0.2O2 with the P2-structure is the best candidate for application as a cathode in Na-batteries. However, a deep discharge of the material below 1.6 V to reach the Na1.0Co0.8Ti0.2O2 composition is detrimental as well, since some amount of Co2+ appears, negatively influencing the cycling behavior.

RUNX1 Isoforms Regulate RUNX1 and Target-Genes Differentially in Platelets/Megakaryocytes: Association with Clinical Cardiovascular Events

RUNX1 is an essential transcription factor for hematopoiesis. Germline RUNX1 haplodeficiency is associated with thrombocytopenia, platelet dysfunction and predisposition to myeloid malignancies. Three major RUNX1 isoforms (A, B and C) are recognized and share a DNA binding RUNT domain; RUNX1A lacks the transactivation domain. Two distinct promoters regulate RUNX1 expression: distal P1 regulates RUNX1C; proximal P2 regulates RUNX1B and RUNX1A. Little is known regarding the differential effects of isoforms in RUNX1 autoregulation, target-gene regulation and association with clinical events. We performed studies in megakaryocytic HEL cells, HeLa cells (which do not express RUNX1) and in platelets of healthy subjects (n=74) and provide evidence for isoform-specific differential autoregulation and target-gene regulation by RUNX1. We show an association between expression of specific RUNX1-regulated genes in whole blood with cardiovascular events in patients. There are 5 RUNX1 consensus binding sites in P1 promoter and 1 in P2 promoter within ~1000 bp from ATG. Wild type RUNX1 P1 and P2 promoter regions were individually cloned into PGL4 luciferase promoter vector. ChIP studies using PMA-treated megakaryocytic HEL cells showed RUNX1 binding to chromatin regions encompassing the RUNX1 binding sites in both promoters. Mutations of 2 RUNX1 binding sites in intron region of P1 promoter reduced promoter activity; mutations of first 2 RUNX1 binding sites at the exon region of P1 promoter increased activity. Mutation of single RUNX1 binding site in P2 promoter increased promoter activity. Thus, RUNX1 binds to P1 and P2 promoters to regulate activities. To examine the RUNX1 autoregulation by individual isoforms, we co-transfected each isoform with P1 or P2 promoter vector in HeLa cells, which do not express endogenous RUNX1. In response to RUNX1B over-expression, both P1 and P2 promoters showed a dose-dependent decrease in promoter activity. RUNX1C over-expression increased P1 and P2 promoter activities. Thus, RUNX1B and RUNX1C regulate P1 and P2 promoters differentially. In HEL cells, which have endogenous RUNX1, RUNX1B overexpression decreased RUNX1C and RUNX1A mRNA/protein expression by ~50%. RUNX1C overexpression increased RUNX1B and RUNX1A mRNA/protein expression. Thus, RUNX1B decreases RUNX1C and RUNX1A expression; RUNX1C increases RUNX1B and RUNX1A. We studied the regulation by RUNX1 isoforms of target genes PCTP (phosphatidylcholine transfer protein), MYL9 (myosin light chain), PDE5A (phosphodiesterase 5A) and F13A (factor XIIIA) . In HeLa cells. RUNX1B overexpression increased PCTP, MYL9 and PDE5A (protein and mRNA); RUNX1C overexpression reduced PCTP and MYL9. In HEL cells RUNX1B increased PCTP, MYL9, PDE5A and F13A expression; RUNX1C reduced PCTP and MYL9 expression. To obtain evidence in vivo, we studied the relationships between RUNX1 isoforms and their relationships to RUNX1-target genes by RNAseq in leukocyte-poor platelets (74 healthy donors; ages 30-75 yrs). RUNX1B correlated negatively with RUNX1C (R= -0.413 and p=1.5e-06) and RUNX1A (R= -0.493 and p=0.00e+oo); RUNX1C correlated positively with RUNX1A (R=0.45, p<0.0001). RUNX1B correlated positively with PCTP, F131A, PDE5A and RAB1B, and negatively with MYL9 (Figure 1); no significant relationships were observed with RUNX1C or RUNX1A. To understand the relationships to cardiovascular events (MI or death), we explored whole blood gene expression using microarrays in 587 patients (2 cohorts, 190 and 397 patients) presenting to cardiac catherization for chest pain and followed for 3.8 years. In our previous studies RUNX1B transcripts were higher and RUNX1C lower in those with MI or death. We now found that higher expressions of F13A1(Figure 2) and RAB31, which have been shown by us to be RUNX1-targets, were associated with cardiovascular events. Conclusions: RUNX1 isoforms autoregulate RUNX1 expression differentially and regulate target genes in a differential manner, a pattern consistent with in vivo platelet gene expression. The relative expression of RUNX1B and RUNX1C isoforms and of their target genes associate with clinical cardiovascular events. RUNX1-isoform specific effects need to be considered in clinical scenarios where RUNX1 is involved and in its pharmacologic modulation.

Features of the crystal structure of 2D honeycomb frustrated magnet Li<sub>2</sub>Ni<sub>2</sub>TeO<sub>6</sub>

Using neutron powder diffraction at a temperature of 35 K, slightly above the Neel temperature, the features of the crystal structure of two samples of layered honeycomb oxides of the same stoichiometric composition Li2Ni2TeO6 synthesized from precursors, Na2Ni2TeO6 and K2Ni2TeO6, were determined. They have a similar crystal structure, hexagonal space group P63/mcm, structure type P2, but there is a significant difference in the distances between the layers. Both Li2Ni2TeO6 samples crystallize into the orthorhombic space group Cmca, with minor differences in the unit lattice parameters. If Li2Ni2TeO6 from the potassium precursor is single-phase, then the compound from the sodium precursor contains 16 wt % of an additional phase with the same Li2Ni2TeO6 stoichiometry, but more deformed with monoclinic distortions described by the С2/m space group.

Mimosa tannin based NIPU wood adhesive with significant substitution of hexamethylenediamine using polyethyleneimine

Tannin-based non-isocyanate polyurethane (NIPU) adhesive exhibits an excellent performance for wood bonding, but contains excess toxic hexamethylenediamine (HMDA), which is emitted to the environment during the preparation of wood panels. Herein, branched polyethylenimine (PEI)/tannin mixtures were utilized to share this adhesive in one integral formulation via various additions at the expense of HMDA. The physical properties, including pH, non-volatile content, viscosity, tannin- and bio-sourced-contents were investigated and compared to a traditional NIPU. The results have shown that the viscosities of the modified adhesives were increased significantly, with improvements at about 2–5% of bio-sourced content and around 4–8% of tannin content being achieved. Moreover, the HMDA content was decreased from 31 % for control T-NIPU-0-0 adhesive to 19 % for the modified adhesives. Possible undergoing reactions of the tannin-NIPU based adhesives series was investigated by Fourier transform infrared spectroscopy (FT-IR) and 13C nuclear magnetic resonance (NMR) analyses. The main tannin-based NIPU structure was maintained even after tannin/PEI mixtures were added. Thermomechanical analysis (TMA) results showed two typical curing stages for either the control adhesive (T-NIPU-0-0) or the modified ones, but different curing performance was observed for modified adhesives, particularly at the first stage. The thermal stability of the modified adhesives was enhanced due to the inserted tannin/PEI mixture, which was proven by thermogravimetric analysis (TGA). The mechanical properties indicated that formulations with suitable weight ratios of tannin/PEI mixtures, such as T-NIPU-4-1 and T-NIPU-5-1 adhesives, could hold a similar performance to the control T-NIPU-0-0 adhesive, which satisfied the European Norm EN 312–2010 for 12- mm boards of type P2. Moreover, a small addition of glycerol diglycidyl ether (GDE) into the T-NIPU-4-1 adhesive endowed an acceptable bonding performance while undergoing different preparation conditions. Therefore, the modified adhesives with the branched PEI/tannin adduct inherited outstanding bonding performance compared to classical tannin-NIPU adhesives along with a noteworthy decreased release of harmful substances such as HMDA, which is in line with the requirements for a cleaner production process.

Phasic regulation of the ATP/P2X7 receptor signaling pathway affects the function of antigen-presenting cells in experimental autoimmune uveitis.

Purinergic ligand-gated ion channel 7 receptor (P2X7R) is a purine type P2 receptor that is expressed on a variety of immune cells. Recent studies have shown that P2X7R signaling is required to trigger an immune response, and P2X7R antagonist-oxidized ATP (oxATP) effectively blocks P2X7R activation. In this study, we investigated the effect of phasic regulation of the ATP/P2X7R signaling pathway on antigen-presenting cells (APCs) by constructing an experimental autoimmune uveitis (EAU) disease model. Our results demonstrated that APCs isolated from the 1st, 4th, 7th and 11th days of EAU presented antigen function and could stimulate the differentiation of naive T cells. Moreover, after stimulation by ATP and BzATP (a P2X7R agonist), antigen presentation, promoting differentiation and inflammation were enhanced. The regulation of the Th17 cell response was significantly stronger than that of the Th1 cell response. In addition, we verified that oxATP blocked the P2X7R signaling pathway on APCs, attenuated the effect of BzATP, and significantly improved the adoptive transfer EAU induced by antigen-specific T cells cocultured with APCs. Our results demonstrated that at an early stage of EAU, the ATP/P2X7R signaling pathway regulation of APCs was time dependent, and the treatment of EAU could be achieved by intervening in P2X7R function on APCs.

Characterisation of a composite material with polyester matrix reinforced with particles from doum palm (hyphaene thebaica) fruit

The objective of this paper is to extract the hulls of Hyphaene thebaica fruit to elaborate a composite material with polyester matrix and to characterize it physically and mechanically. The first step of the process consisted of crushing, drying and then physically characterizing the hulls. The obtained results show that the average density is 766 kg/m3, the kinetic of water absorption is 40.39% and the average kinetic of humidity is 9.23%. The second step of the process consisted of crushing and sieving the hulls in order to classify them in four different sizes, and then proceeding to the manufacture of panels according to the different sizes of particles and different dosages. Another phase of characterisation has thus been achieved and the following results have been obtained: general theoretical density is 1275.86 kg/m3; average apparent density is 0.892 g/cm3, and the average density of the shells is 0.766 g/cm3. The average porosity rate obtained is 0.3%. As for the mechanical characteristics obtained by the three-point bending, the results on the average flexural modulus of elasticity (MOE) are presented as follows: 3400 ± 511 MPa for 10%–90% and size 0.5–2.5 mm, 4100± 320 MPa for 15%–85% size less than 0.5 mm; 5730± 212 MPa for 30%–70% size 0.5–2.5 mm; 6510± 211 MPa for 15%–85% size 0.5–2.5 mm; 5880± 110 MPa for 30%–70% size less than 0.5 mm. The corresponding flexural breaking strength (MOR) are respectively: 12.8± 0.2 MPa; 13.5± 0.2 MPa; 12.0± 0.5 MPa; 10.8± 0.2 MPa and 13.8± 0.3 MPa. The methods used in this work are experimental. These results allowed to deduce that the composites elaborated are particleboard type P2 and have the advantage to be used as panels useable in furniture, thermal and acoustic insulation and as structural materials. Thus, it is also possible to use it as an abrasive aggregate for sanding. All prepared particleboards had exterior and interior quality capabilities, for both working and non-working environments. It is also possible to use it as an abrasive aggregate for sanding.

Influence of Isocyanate Content and Hot-Pressing Temperatures on the Physical–Mechanical Properties of Particleboard Bonded with a Hybrid Urea–Formaldehyde/Isocyanate Adhesive

Particleboard (PB) is mainly produced using urea–formaldehyde (UF) adhesive. However, the low hydrolytic stability of UF leads to poor water resistance by the PB. This research aimed to analyze the effect of hot-pressing temperatures and the addition of methylene diphenyl diisocyanate (MDI) in UF adhesive on the physical and mechanical properties of PB. The first experiment focused on pressing temperature treatments including 130, 140, 150, and 160 °C. The particles were bonded using a combination of UF and MDI resin at a ratio of 70/30 (%w/w). Furthermore, the second experiment focused on UF/MDI ratio treatment, including 100/0, 85/15, 70/30, and 55/45 (%w/w), and the particles were pressed at 140°C. All of the single-layer particleboard in this research were produced in 250 × 250 mm, with a target thickness and density of 10 mm and 750 kg/m3, respectively. This research used 12% resin content based on oven-dry weight wood shaving. The pressing time and pressing pressure were determined to be 10 min and 2.5 N/mm2, respectively. Before the tests, the board was conditioned for 7 days. When studying the effect of treatment temperature, good physical properties (thickness swelling and water absorption) and mechanical properties (MOR and MOE) were obtained at 140 °C. However, no significant difference was observed in the UF/MDI ratio between 85/15 and 55/45 using the same temperature. The increase in the MDI adhesive ratio improves the MOE and MOR values. However, the internal bond was the contrary. This study suggests that a combination of UF/MDI at a ratio of 85/15 and hot-pressing temperature at 140 °C could produce a PB panel that meets a type 8 particleboard according to the JIS A5908-2003 standard and type P2 according to the EN 312-2010 standard.

Research on fluid mobility in tight-sandstone with a NMR fractal theory pore classification method

The fluid mobility characteristics in the pores with various apertures for tight-sandstone would finally determine the fluid mobility and production of tight oil and gas reservoirs. In this study, the tight-sandstone core samples collected from Middle Jurassic Xishanyao Formation in Santanghu Basin were launched the fluid mobility measurements under various centrifugal speeds. With the NMR fractal theory pore classification method, the various types of pores in the tight-sandstone core samples were classified, and the fluid mobility in different types of pores were also investigated. The results show that the tights-sandstone core samples were significantly influenced by compaction, and the core samples are relatively dense, the mineral intergranular solution pores and colloidal intergranular pores are the main storage spaces. With a constant increase of the centrifugal speed, the fluid mobility increases continuously, and the fluid mobility for CTOS-19 features stronger than that of CTOS-7, which is related to the complexity of pore structure in tight-sandstone sample. Compared with the pore aperture in CTOS-19, the pore aperture in CTOS-7 is smaller, and the connectivity between the smaller and larger pores is poorer, leading to the poorer fluid mobility. Besides, the NMR fractal theory pore classification method also shows that the COTS-7 features more pore types than COTS-19, five and four types respectively. The type P2 and P3 pores are dominant in COTS-7 and CTOS-19 core samples, and the connectivity between type P2 and P3 pores contributes dominantly to the fluid mobility. With the NMR fractal theory pore classification method, the complexity of the distribution of fluid and fluid mobility in tight reservoirs could be studied quantitatively, and the results can efficiently guide the development of residual oil and gas in tight oil reservoirs.

Bio-based materials from sunflower co-products, a way to generate economical value with low environmental footprint

Sunflower co-products (i.e., stalks and heads) were recently used to create a value chain of sunflower biomass. On the one hand, bioactive ingredients extracted through twin-screw extrusion can be valorized as ecologically friendly agricultural products. On the other hand, in this study, the remaining solid,i.e., the extrudate, was used for obtaining bio-based materials, generating economical value with low environmental footprint. It is processable into cohesive boards through hot pressing. According to NF EN 312, optimal board (37 MPa flexural strength, and 33% thickness swelling) containing 9.1% (w/w) sunflower proteins as binder can be used as a type P2 board,i.e., for interior fittings (including furniture) in dry environments. For P3 and P4 types, a thickness swelling lower than 20% and 21%, respectively, will be required. The extrudate can be also separated into long fibers and fines. Long fibers can be compression molded into low-density insulation blocks (49 mW/m K thermal conductivity). Fines can be used as a filler for reinforcing (bio)plastics,e.g., polypropylene and poly (lactic acid). These bio composites could be injected into pots or tutors for plants, or even extruded into window openings or exterior decking.

Management of Forest Residues as a Raw Material for the Production of Particleboards

Expanding the base of raw materials for use in the production of wood-based materials, researchers and panel manufacturers around the world are increasingly trying to produce panel prototypes from raw materials available in a given area and climate, or by managing waste from wood industry processing. The aim of the study was therefore to test the hypothesis that forest residues de-rived from Scots pine roundwood harvesting have the same suitability for the production of three-layer particleboard as the wood of the most valuable part of the Scots pine stem, by comparing selected properties of raw wood material and final product—particleboard. Characterization of both the raw material and the physical-mechanical and hygienic properties of the produced panels was carried out. For these panels from the tree trunk, MOR was 14.6 N/mm2, MOE 1960 N/mm2 and IB 0.46 N/mm2. The MOR and IB values turned out to be higher for the panel from the branch and are 16.5 and 0.72 N/mm2, respectively. Excessive swelling of the panels resulted in all manufactured particleboards meeting the standardized performance requirements of EN 312 for interior furnishing panels (including furniture) for use in dry conditions (type P2).

Polio returns to the USA: An epidemiological alert

On July 21, 2022, the USA witnessed the first case of poliomyelitis after 3 decades of its eradication. Poliomyelitis is a crippling disease that results from infection with any one of the three related poliovirus types (referred to as types P1, P2, and P3), members of the enterovirus (picornavirus) family. The New York State Department of Health confirmed that a case of paralytic poliomyelitis was reported from a 20-year-old Hungarian traveller residing in Rockland County. The detected viral sequence has been found to have vaccine-derived poliovirus type 2 (VDPV2) suggesting an origin from the live attenuated oral polio vaccine (OPV). Since immunisation remains the only preventable measure, this article explores suggestions from the Centers for Disease Control and Prevention on reliable Inactivated (killed) polio vaccination in high-risk patients along with early case detection and treatment. In light of the above-mentioned findings, this research further details future recommendations like cessation of the OPV, encouragement of inactivated polio vaccine (IPV) in vaccination schedules, sensitive epidemiological surveillance system and appropriate training for healthcare providers. The affected countries have been further advised to have effective outbreak response strategy plans in place so that they can respond and stay prepared for such outbreaks in the future.

Eco-Friendly Adhesives Based on the Oligomeric Condensed Tannins-Rich Extract from Alder Bark for Particleboard and Plywood Production.

Toxic formaldehyde emissions, and the necessity to reduce the consumption of petrochemicals, stimulates the development of environmentally friendly adhesives. The aim of this research was to study, for the first time, the possibility of using condensed tannins (CTs)-rich extracts from grey alder (Alnus incana) and black alder (Alnus glutinosa) bark in the production of particleboards and plywood adhesives. The chemical structure, composition, and molecular weight of the CTs were identified by a 13C-NMR and TOF-MS analysis. Three innovative adhesive systems were studied: CTs-phenol-formaldehyde (CTs-PF) resin; a CTs-polyethyleneimine (PEI) adhesive system; and CTs–PEI combined with an ultra-low emitting formaldehyde resin (ULEFR)—CTs–PEI–ULEFR. The results showed that CTs-PF resin has properties close to commercial PF resin, and the formaldehyde emission was twice lower. CTs–PEI bonded particleboards corresponded to the requirements of the EN 312:2010 standard for particleboards in dry conditions (Type P2). CTs–PEI–ULEFR, with a 40–60% substitution of ULEFR by CTs–PEI, had adhesive properties very close to ULEFR; the plywood shear strength fit the requirements of the EN 314-2:1993 standard for application in internal and external system conditions. The introduction of extracted alder bark residues microparticles into the composition of the adhesive system showed their positive potential for application as a filler.

Association between stage and histopathological type of nasopharyngeal cancer on occurrence of postirradiation otitis media with effusion

IntroductionIndonesia is one of the countries with the highest incidence of nasopharyngeal cancer (NPC), 6.2 out of 100,000 population/year. Radiotherapy is one of the main treatment options for NPC. Otitis media with effusion (OME) is the most common ear complication of radiotherapy for NPC patients. ObjectiveThis study aimed to determine the association between the stage and histopathological type of NPC on the occurrence of OME. MethodThis study used a cross-sectional method, data were taken retrospectively from medical records based on inclusion and exclusion criteria for the period January 2015–December 2019. Results131 patients met the inclusion and exclusion criteria. There were 87 men and 44 women, with the largest age range being 46–55 years (49%). Most (51%) had stage III NPC, followed by stage IV A by 28%. The histopathological type is mostly undifferentiated non-keratinized NPC in 90 patients (69%) and 34 patients with differentiated nonkeratinized types (26%). The association between stage (p1) and histopathological type (p2) of NPC with the incidence of OME after radiotherapy showed insignificant results (p1 = 0.272 and p2 = 0.101). ConclusionOtitis media with effusion in post irradiated nasopharyngeal carcinoma patients occurred in 18.3%. Postirradiation OME generally occurs in men with the age range of 46–55 years, NPC stage III and non-keratinizing undifferentiated histopathological type. There was no significant association between stage and histopathological type of NPC with the occurrence of postirradiation OME.

The Anti-Biofilm Efficacy of Caffeic Acid Phenethyl Ester (CAPE) In Vitro and a Murine Model of Oral Candidiasis.

Candida albicans is the main fungal species associated with the development of oral candidiasis. Currently, therapeutic options for these infections are limited by the adverse effects of antifungal drugs and by the emergence of drug resistant strains. Thus, the development of new antifungal agents is needed for the prevention and treatment of oral Candida infections. Caffeic acid phenethyl ester (CAPE) is a natural compound from propolis polyphenolic groups that exhibits many pharmacological properties. In this study, we investigated whether CAPE can have antifungal and immunomodulatory effects on oral candidiasis. Preliminary tests to assess the antifungal activity of CAPE were performed using the Minimum Inhibitory Concentration (MIC) assay that demonstrated inhibition in a range from 16 to 32 μg/mL, confirming its antifungal activity on several C. albicans strains isolated from the oral cavity. Subsequently, we analyzed Candida spp biofilms formed in vitro, in which CAPE treatment at 5 x MIC caused a reduction of 68.5% in the total biomass and ~2.60 Log in the viable cell count (CFU/mL) in relation to the untreated biofilm (p<0.0001). Next, RNA was extracted from untreated and CAPE-treated biofilms and analyzed by real-time qPCR. A series of genes analyzed (ALS1, ECE1, EPA1, HWP1, YWP1, BCR1, BGR1, CPH1, EFG1, NDT80, ROB1, TEC1, UME6, SAP2, SAP5, PBL2, and LIP9) were downregulated by CAPE compared to the untreated control group (p<0.0001). In in vivo studies using Galleria mellonella, the treatment with CAPE prolonged survival of larvae infected by C. albicans by 44.5% (p < 0.05) and accompanied by a 2.07-fold increase in the number of hemocytes. Flow cytometry revealed the most prominent increases were in types P2 and P3 hemocytes, granular cells, which phagocytize pathogens. In addition, CAPE treatment decreased the fungal load in the hemolymph and stimulated the expression of antifungal peptide genes such as galiomicin and gallerimycin. The antifungal and immunomodulatory activities observed in G. mellonella were extended to a murine model of oral candidiasis, in which CAPE decreased the levels of C. albicans colonization (~2 log CFU/mL) in relation to the untreated control group. In addition, CAPE treatment significantly reduced pseudomembranous lesions, invasion of hyphae on epithelium surfaces, tissue damage and inflammatory infiltrate (p < 0.05). CAPE was also able to increase the expression of β-defensin 3 compared to the infected and untreated group by 3.91-fold (p < 0.0001). Taken together, these results show that CAPE has both antifungal and immunomodulatory effects, making it a promising natural antifungal agent for the treatment and prevention of candidiasis and shows impact to oral candidiasis.

Mechanical and physical properties of boards made from recycled paper

Due to the increasing accumulation of wastes around the world, the demand for sustainable products is increasing. Paper is a commonly disposed of material that can pose problems even when it is recycled. The concept of using cardboard (CB) as a material for furniture production has been around for many years, but CB furniture does not last long. This study examined the feasibility of using post-consumer recycled paper to produce paper-based boards for furniture design. Cardboard (CB) and office paper (OP) were the main post-consumer materials that were used. The CB and OP were mixed with polylactic acid (PLA) and limestone. The boards were made at a temperature of 200 °C and pressed at a pressure of 3.5 N/mm2 using a single opening hydraulic press. The physical and mechanical properties were tested according to the European standards for wood-based panels. Tests that are critical for furniture parts, such as the modulus of rupture (MOR), the modulus of elasticity (MOE), the internal bond, the screw withdrawal resistance, the thickness swelling, and the water absorption were examined. The paperboard samples exceeded some of the requirements for the general use of boards for interior fitments (including furniture) for use in dry conditions (Type P2) and for non-load bearing boards for use in humid conditions (Type P3).

Oversized Planer Shavings for the Core Layer of Lightweight Particleboard.

Planer shavings (PS) are side-products generated during the processing of solid wood, typically used for heating, packaging, or insulation purposes. PS has been used for decades in particleboard manufacture, particularly in the core layer. The aim of this research is to investigate the use of PS with a length over 4 mm in low-density one-layer particleboard manufacturing with a thickness of 10 mm, as an option to reduce the raw material demand for wood-based panels. Correlations towards the mechanical properties of the particleboards, fabricated at a density of 475 kg/m3, could be drawn by analyzing the effects of different urea-formaldehyde adhesive contents (6%, 9%, and 12%). Two methods of adhesive application (pouring and spraying) and two types of blending of PS with adhesive (plowshare mixer and drum mixer) were investigated, with the aim that PS will have controlled resin application. The difference between the adhesive application methods was examined by analyzing the mechanical properties as an internal bond, modulus of rupture, and modulus of elasticity as well as indirectly by visualizing the adhesive distribution by adding a green pigment to the adhesive before application. PS demonstrated reduced bending properties in comparison with the EN 312 standard requirements of particleboards for internal use in dry conditions (type P2), due to the low density. The internal bond strength in the case of the particleboard without pigment application (up to 0.5 N/mm2) was higher compared to the P2 requirements (0.4 N/mm2), and significantly lower (0.15 N/mm2) in combination with the pigment (2.5% based on the board weight, compared to 0.1%, specific for such industry applications), but still superior to the values of the reference panel manufactured with wood particles.

Properties of particleboards made from sugarcane bagasse particles

The objective of this work was to evaluate the physical-mechanical properties and the density profile of panels produced with sugarcane bagasse particles with two sizes (0.50 and 0.85 mm) and with pre-treatment (particles treated in hot water at 70 °C for two hours) and without pre-treatment. The nominal density of the panels was 0.65 g cm-3. The cycle parameters were 35 kgf cm-2 of pressure, temperature of 180 °C and 10 min of pressing. The physical and mechanical tests were performed according to the requirements of NBR 14810-2006. The density profile of the particleboards was obtained by X-ray densitometry. The water absorption in two hours was higher in the panels produced with particles treated in hot water. The other physical and mechanical properties were not influenced by the evaluated factors. The apparent density varied along the thickness of the panels, with more pronounced peaks in the outer layers, thus presenting a vertical density gradient within the normal range for this type of panel. The physical-mechanical properties do not meet the minimum requirements by the NBR 14810 (2006) for nonstructural panels for indoor use in dry conditions (Type P2).

The P-y Response of Laterally Loaded Flexible Piles in Residual Soil

This paper describes the main features related to lateral displacements with depth after successive lateral loading–unloading cycles applied to the top of reinforced-concrete flexible bored piles embedded in naturally bonded residual soil. The bored piles under study have a cylindrical shape, with 0.40-m in diameter and 8.0-m in length. Both bored piles types (P1 and P2) include an embedded steel pipe section in their center as longitudinal steel reinforcements: pile type P1 has another 16 steel rods as steel reinforcement to concrete while pile type P2 has no further steel reinforcement. Pile type P1 has three times as much stiffness (EI) and four and a half times the plastic moment (My) than pile type P2. A similar load–displacement performance was observed at initial loads as for small displacements of both piles. At this initial loading stage, the response of the reinforced concrete piles is a function of the soil characteristics and of a linear elastic pile deformation. During this stage, piles can even be understood as probes for evaluating soil reactions. For larger horizontal displacements, after the concrete section starts undergoing large deformations, approaching the ultimate bending moment, pile behavior and consequently the load–displacement relation starts to diverge for both piles. For pile P1 the values of relevant lateral displacements are extended to about 2.5-m in depth, while for pile P2 lateral displacements are mostly constrained to about 2.0-m in depth. Measurements of horizontal displacements of pile P1 against depth recorded with a slope indicator show that, after unloading, lateral loads at distinct stages (small and near failure loads), exhibits a much higher elastic phase of the system response. An analytical fitting model of soil reaction is proposed based on the measured displacements from slope indicator. The integration of a continuous model proposed for the soil reaction agrees fairly well with the measured displacements up to moments close to plastic limit. Results of load–displacement show that the stiffer pile (P1) was able to mobilize twice as much lateral load compared to pile P2 for a service limit displacement of about 20 mm. The paper shows results that enable the isolation of the structural variable through real scale pile load tests, thus granting understanding of its importance and enabling its quantitative visualization in examples of piles embedded in residual soil sites.