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This research centered on enhancing the mechanical properties of sustainable composite materials made from short flax fibers. Challenges associated with fiber–matrix adhesion and moisture absorption were systematically addressed. A water–alginate pre-treatment, combined with plasma modification, was employed to stabilize the fibers, ensuring their optimal preparation and improved compatibility with biopolymers. A thorough investigation of the effect of the plasma modulation using a duty cycle (DC) was conducted, and extensive physicochemical and mechanical analyses were performed. These efforts revealed conditions that preserved fiber integrity while significantly improving surface characteristics. Techniques such as optical emission spectroscopy (OES), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and Dynamic Mechanical Analysis (DMA) were utilized, providing a comprehensive understanding of the transformations induced by the plasma treatment. The findings underscored the critical role of alginate and precise plasma settings in enhancing the mechanical properties of the composites. Ultimately, this study made a substantial contribution to the field of eco-friendly materials, showcasing the potential of short flax fibers in sustainable composite applications and setting the stage for future advancements in this area.

Significant progress has been made in recent years in the use of atmospheric pressure plasma techniques for surface modification. This research focused on the beneficial effects of these processes on natural by-products, specifically those involving natural fiber-based materials. The study explored the deposition of hydrophobic organosilicon-like thin films onto flax fibres through plasma-enhanced chemical vapour deposition (PECVD), using tetramethylcyclotetrasiloxane (TMCTS) as the precursor. After the successful deposition of hydrophobic organosilicon-like thin films onto the flax fibres, polylactic acid (PLA) composite materials were fabricated. This fabrication process sets the stage for an in-depth analysis of the modified materials. Subsequently, these flax fabrics were subjected to meticulous characterization through scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and contact angle measurements. The results demonstrated successful TMCTS deposition on the surface which led to a complete hydrophobization of the flax fibers. Mechanical tests of the PLA/flax fibre composites revealed a significant improvement in load transfer and interfacial compatibility following the surface modification of the flax fibres. This improvement was attributed to the enhanced adhesion between the modified fibres and the PLA matrix. The findings highlight the potential of TMCTS-based PECVD as a practical surface modification technique, effectively enhancing the mechanical properties of PLA/flax fibre composites. These developments open exciting possibilities for sustainable and high-performance composite materials in various industries.

Ammonium polyphosphate (APP) was grafted onto the surface of exfoliated graphite nanoplatelet (GNP) to obtain a novel flame retardant, GNP-g-APP, and thereafter was incorporated into the ethylene vinyl acetate (EVA) to improve its flame retardancy. The chemical structures of the precursors and the target product were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and energy dispersive X-ray spectroscopy (EDS) techniques. FTIR spectra appeared at 1056 and 1103 cm−1 were attributed to POC asymmetric stretching bond, that conformed formation of GNP-g-APP. Thermal stability behaviour and flame retardancy performance of the samples were evaluated by TGA, UL-94, micro-calorimetry, and cone calorimetry. TGA measurements revealed the superiority of GNP-g-APP over GNP. The micro-calorimetry analyses indicated a sharp fall in both the total heat release (THR) and the peak of heat release rate (pHRR) of EVA containing 30 wt.% GNP-g-APP, evidenced by a thick char layer formed as barrier. Cone calorimetry confirmed flame-retardant effect of GNP-g-APP featured by a reduction in pHRR (−63 %) and THR (−31.6 %) due to the formation of a cohesive char layer. Although GNP addition sharply decreased the elongation at break of 70/30 (w/w) composites from 500% for neat EVA to 71%, a very promising value of 364% for EVA/GNP-g-APP sample preserved superior flexibility.

The destructive effects of sun UV radiation on human skins are now very clear to everyone. Most of the present studies were focused on the fabrics’ structural parameters such as density, warp and weft yarns finenesses, fabric pattern and printing or finishing treatments applied to the fabrics. The aim of this work is achieving a technique through which the produced fabrics possess a higher UV-protection ability. For this purpose, two different metals including aluminium and copper yarns were employed in fabrics production process and their effects on UV-protection ability of the produced fabrics were investigated. Six different fabric samples comprised of either cotton/polyester, nylon yarns as the warp yarns as well as either aluminium or copper yarns as the weft yarns were produced. Using the spectrophotometer technique, which is known as one of the UPF measuring method, the absorbency and reflectivity of fabrics within the specified range of electromagnetic waves (specially the UV radiation) were determined. The results illustrated that the higher UV absorbency was related to the fabric possessing the copper yarns in their structures. It was concluded that the absorption ability of nylon fabrics is higher than that of the cotton/polyester samples.

Objective:One of the most common joint dislocations presented to the emergency department (ED) is anterior shoulder dislocation (ASD). Various techniques for the treatment of this abnormality have been suggested. In this study, we evaluated the efficacy and success rate of modified scapular manipulation (MSM) as a painless procedure compared to traction-countertraction (TCT) for reduction of ASD. Methods:Patients with ASD who were presented to ED of Baqiyatallah Hospital, Tehran during 2011 were included. They were randomly divided into MSM group or TCT group and then pain at reduction, time of reduction, duration of hospitalization, and success rate were compared. In TCT group, reduction was performed using sedative and antipain medications. Results: Ninety seven patients (81.6% male) with a mean age of 34.15 years±13.48 years were studied. The reduction time between both groups showed a significant difference (470.88 seconds±227.59 seconds for TCT group, 79.35 seconds±82.49 seconds for MSM group, P

A series of samples based on poly(3-hydroxybutyrate) (PHB) containing five different additives were prepared and their thermal stability and flammability were discussed. The samples first underwent flammability screening by using Pyrolysis Combustion Flow Calorimeter (PCFC) analyses. Then, four samples were selected for further investigations. PHB composites containing sepiolite (Sep.) inorganic nanofiller, and also organic ammonium polyphosphate (APP) were examined for flammability and thermal behavior using PCFC, thermogravimetric analysis (TGA), flame test, and Differential Scanning Calorimetry (DSC) analyses. Moreover, burning behavior of samples were captured on a digital camera to give a deeper sense of their flammability character for comparison. The results revealed a significant improvement of flammability and thermal stability of composites, particularly in the presence of sepiolite with respect to the value obtained for unfilled PHB. Regarding TGA results, the char residue yield was increased to ca. 20.0 wt.% in the presence of sepiolite, while 0.0 wt.% was observed for PHB. PCFC measurements uncovered higher performance of PHB-Sep. sample as signaled by 40% reduction in the peak of heat release rate with respect to PHB. According to observations, PHB-Sep. sample showed non-dripping behavior with high capacity of charring in the presence of Sep. in a vertical flame test.

Study on collapsibility of oriental beech (Fagus orientalis) and paulownia (Paulownia fortune) woods due to their hydrothermal modification as well as the wettability and the water absorption were the main concerns of this research work. Out of these species, blocks of sizes 50×6×6cm were prepared and treated at temperatures of 130 and 150°C with a holding time of 30min in a stainless steel reactor containing the water. Oven dried weights and dimensions of the blocks were measured before and after the hydrothermal treatment to determine the density, collapsibility and mass loss due to applied treatment. Furthermore, small blocks of the treated wood were prepared and soaked in water for 1000-hr to determine their water absorption. The wettability of the woods were also measured to determine the water repellency. Results revealed that any raise of treatment temperature up to 150°C increases the density and the collapsibility. Treated wood collapsed in all directions; however, tangential collapse was much worse than the other directions. The contact angle was increased by rise of the treatment temperature. Hydrothermal treatment has reduced water absorption and increased the hydrophobicity of the woods.

Background: Pneumothorax is a potential life-threatening condition especially in patients with underlying disorders. In this study we compared the diagnostic accuracy of general practitioners and emergency medicine specialists in interpreting chest x-rays (CXR) suspected of having iatrogenic pneumothorax in emergency departments. Methods: This cross-sectional study was conducted in Shahid Chamran Hospital in Tehran, Iran during 2008- 2010. The study was designed to compare the ability of general practitioners and emergency medicine specialists in diagnosing iatrogenic pneumothorax regarding 500 CXRs of one-hundred patients admitted for upper central venous catheterization. Results: General practitioners and emergency medicine specialists could accurately (P0.05). Conclusion: These findings indicate that the diagnostic accuracy of emergency medicine specialists is significantly higher than those of general physicians. The diagnostic accuracy of both physician groups was higher than the values in similar studies that signifies the role of relevant training given in the emergency departments of the Hospital.

Abstract Background and Objective: Propionibacterium acne is one of the main causes of acne. Due to the spread of drug resistance, it is not responsive to treatment. This study aimed to determine antibiotic sensitivity of strains of the Propionibacterium acne. Material and Methods: seventy samples of acne lesions were collected to study the presence of Propionibacterium acne. Microbial Culture technique was used to detect and identify Propionibacterium acne. Antibiotic resistance of the isolates to the antibiotics of Doxycyclin, Azithromycin, Erythromycin, Tetracycline, Clindamycin and Trimethoprim sulfamethoxazole was studied by Antibiogram method. Results: Of 70 samples, 14 (20%) were positive for Propionibacterium acne. The results of phenotypic test were confirmed using molecular method. Rate of resistance to Azithromycin and Erythromycin (50%), Clindamycin (35.71%), Trimethoprim sulfamethoxazole (28.57%), Doxycycline and Tetracycline (14.29%) was determined. Conclusion: Outbreak of antibiotic resistance to Azithromycin, Erythromycin, and Clindamycin is high. Since the Propionibacterium acne is sensitive to Doxycycline and Trimethoprim Sulfamethoxazole, it is recommended using them to treat acne. Keywords: Antibiotic susceptibility, Propionibacterium Acne, Ance Protein.

The identification of Mycobacteria in the species level has great medical importance. Biochemical tests are laborious and time-consuming, so new techniques could be used to identify the species. This research aimed to the comparison of biochemical and sequencing 16S rDNA gene methods to identify nontuberculous Mycobacteria in patients suspected to tuberculosis in Golestan province which is the most prevalent region of tuberculosis in Iran. Among 3336 patients suspected to tuberculosis referred to hospitals and health care centres in Golestan province during 2010-2011, 319 (9.56%) culture positive cases were collected. Identification of species by using biochemical tests was done. On the samples recognized as nontuberculous Mycobacteria, after DNA extraction by boiling, 16S rDNA PCR was done and their sequencing were identified by NCBI BLAST. Of the 319 positive samples in Golestan Province, 300 cases were M.tuberculosis and 19 cases (5.01%) were identified as nontuberculous Mycobacteria by biochemical tests. 15 out of 19 nontuberculous Mycobacteria were identified by PCR and sequencing method as similar by biochemical methods (similarity rate: 78.9%). But after PCR, 1 case known as M.simiae by biochemical test was identified as M. lentiflavum and 3 other cases were identified as Nocardia. Biochemical methods corresponded to the 16S rDNA PCR and sequencing in 78.9% of cases. However, in identification of M. lentiflavum and Nocaria sp. the molecular method is better than biochemical methods.