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Introduction Septic knee arthritis after elective arthroscopic procedures is a rare surgical emergency, with Pseudomonas aeruginosa even more rarely causing the infection. The treatment by arthroscopic debridement and lavage with diluted Povidone-Iodine has potential benefits that may be useful in improving the prognosis for patients. This case report discusses the potential benefits of using antiseptics like Povidone-Iodine in the washout of the affected joint. Presentation of case We present a patient with post arthroscopic septic knee arthritis caused by P. aeruginosa treated successfully by arthroscopic synovectomy and washout with normal saline and diluted povidone‑iodine, and prolonged antimicrobial therapy. Discussion Preceding reports of P. aeruginosa suggest intraoperative factors, postoperative factors, and host factors that may lead to this uncommon infection. There is controversy over the optimal management regarding arthroscopic versus open debridement, and the choice of the irrigating fluid. Conclusion The use of antiseptics like Povidone-Iodine in the washout procedure may lead to improved outcomes if used for a short controlled period of time and followed by copious irrigation with saline. Further studies must be done to determine the efficacy and risk-to-benefit ratio of this method., Highlights • Pseudomonas aeruginosa causing septic arthritis without any risk factors are unusual. • Treatment approach for septic knee arthritis is controversial. • The type of irrigating fluid used in septic arthritis washout is not well defined by international guidelines • Use of 2.5% Povidine-Iodine in joint lavage for a short time is safe and effective in treating septic arthritis.

In the present study, aqueous extracts were obtained from the leaves and flowers of Vitex pseudo-negundo. The effects of these extracts were examined on the germination percentage and several developmental factors of three plant species, namely, Lepidium sativum, Amaranthus retroflexus and Taraxacum officinale. The major phenolic compounds of the leaf extract were Trans-ferulic acid (913.71 mg/L), Chloregenic acid (235 mg/L) and Hesperedin (115.68 mg/L), while those of the flower were Chloregenic acid (333 mg/L), p-Coumaric acid (256.04 mg/L) and Hesperedin (185.72 mg/L), as recognized by HPLC. The stock extract had a concentration of 10% (w/v) and was made from dried powders of the Vitex flower and leaf. The extract at 2.5% had a stimulatory effect on the seed germination of Lepidium sativum. A substantial increase (P ≤ 0.05) was observed in the germination percentage (98.3 and 96.6%, when using flower and leaf extract, respectively). The 7.5% extract (either leaf or flower) reduced root length to zero in A. retroflexus and T. officinale. However, in Lepidium sativum, there was a significant difference between leaf and flower extracts. At the same concentration (2.5%), leaf extract reduced fresh weight (0.43 g) more than the flower extract did (0.68 g). Taraxacum officinale and Amaranthus retroflexus showed a significant increase in the fresh weight of seedlings (0.2 g and 0.06 g, respectively) in response to the leaf extract (2.5%), compared to the control treatment, which indicates a stimulatory effect. In contrast, the highest concentration (7.5%) caused a significant inhibition (P ≤ 0.05%).

Single-wall carbon nano tubes (SWCNTs) encourage the biosynthesis of bioactive compounds in plants. The current study examined how SWCNTs affect morphological, physiological and biochemical properties of Thyme (Thymus daenensis) callus culture. Sterilized seeds were cultured in Murashige and Skoog (MS) medium. Ten-day-old seedlings were used as explants and were cultured on MS media containing 2, 4-dichlorophenoxy acetic acid (2, 4-D) (2 mg l−1) and benzyl amino purine (BAP) (4 mg l−1). These media were treated with various concentrations of SWCNTs (25, 50, 100, 125, and 250 μg ml−1). A medium without SWCNTs was considered as the control. This study finding revealed that SWCNTs induce changes in callus morphology (i.e. color changes, area, fresh, and dry weight) and physiology (i.e. water content and dehydrogenase activity) as SWCNTs activate antioxidant molecules and some related enzymes (e.g. peroxidase (POD), polyphenol oxidase (PPO), phenylalanine ammonia-lyase (PAL), and Dehydrogenase (DHA)). SWCNTs contribute to the accumulation of compounds that are pharmacologically active (e.g. phenolic acids and flavonoids) in a concentration-dependent manner. Adding SWCNTs to the extracts of callus created a variety of 1, 1-diphenyl-2-picrylhydrazyl radical (DPPH) free radical scavenging activities in the extracts. At the cellular level, optical microscopic images indicated that SWCNTs can reasonably promote cell elongation and reduce chloroplast numbers. Following the addition of SWCNTs to the media, after 30 and 60 days, SWCNTs (50 μg ml−1) were found to encourage better growth in terms of both fresh (0.683 ± 0.50 g, 1.667 ± 1.18 g) and dry biomass (0.058 ± 0.12 g, 0.266 ± 0.17 g), respectively. Also, SWCNTs (50 μg ml−1) increased total phenolic content (TPC) (1.290 ± 0.19 mg GAE g −1 DW), total flavonoids content (TFC) (2.113 ± 0.05 mg QUE g −1 DW), antioxidant activity (74.93 ± 3.1 %), Rosmarinic acid (22.10 ± 0.011 mg. g−1DW), Trans-ferulic acid (0.29 ± 0.02 mg. g−1DW), Catechin (0.44 ± 0.002 mg. g−1DW), Hesperedin (0.45 ± 0.02 mg. g−1DW), Vanilin (0.13 ± 0.01 mg. g−1DW), Carvacrol (0.068 ± 0.01 mg. g−1DW) and enzymes that facilitate the biosynthesis of phenolic compounds like PAL (32.94 ± 13.2 mM cm g −1 FW). In addition, Transmission electron microscopy (TEM) images of T. daenensis callus cells revealed how SWCNTs nano materials can penetrate callus cells and then aggregate together in the cytoplasm and in the cell wall.

Medicinal plants are rich in secondary metabolites that constitute the composition of many drugs. The quantity and quality of these valuable materials are affected by climatic factors and ontogenetic growth stages. In the present study, the effects of climatic factors and different plant parts (leaf, flower and fruit) were examined on the quantity and quality of vitex essential oil (EO) (Vitex pseudo-negundo (Hausskn.) Hand.-Mzt.) in eight different regions where the plant grows. Analysis of EO samples was performed by using GC and GC–MS. Results show that the main EO compounds in vitex are α-pinene (29.5–48.9%), limonene (9.2–14.3%), α-terpinyl acetate (0.6–22%) and (E)-caryophyllene (8.1–17.7%) in different plant organs and ecotypes. The principal component analysis (PCA) was applied to develop a model of the distribution of total EO content in different plant organs based on a complex of environmental factors. The main components were the longitude, latitude, altitude, annual average precipitation and annual average temperature. These components explained about 67% of the variations. Temperature, rainfall and elevation did not show significant independent regression relationships (P ≤ 0.05) with the EO content, but had a significant correlation with some of the compounds in the EO. In different regions where the plant grows, the variations among EO contents ranged from 0.21 to 0.76% in different plant organs. The maximum and minimum EO contents were found in the leaves and fruits, respectively.

In in vitro process of this study, protoscoleces of the hydatid cysts were exposed to two concentrations of nano emulsion (NE) of Zataria multiflora essential oil (ZMEO) (1 and 2mg/mL) for 10 and 20min. Viability of protoscoleces was confirmed using 0.1% eosin staining. For in vivo studies, sixteen laboratory mice were infected intraperitoneally by 1500 live protoscoleces. Five months after infection, the infected mice were divided into treatment and control groups. The mice of treatment group received the NE of ZMEO (20mg/kg) orally via their drinking water while the mice of control group received no treatment. Two months after the start of treatment, all of the mice were necropsied and the hydatid cysts were collected. Subsequently, the numbers, sizes and weights of the collected cysts were compared between the mice of two groups. The results of in vitro scolicidal assays showed that the scolicidal power of NE of a ZMEO at concentration of 1mg/mL was 88.01%, and 100% after 10 and 20min respectively. NE of ZMEO showed 100% scolicidal power at a concentration of 2mg/mL after 10min (comparing to 4.46% for the control group). The results of in vivo studies revealed that the size of the largest cysts as well as the total number of the cysts were significantly lower in the mice treated with NE of ZMEO (P

There is literature detailing the effects of travel motivation, risks perceptions, and travel constraints on the destination image and travel behaviour of individuals. However, literature explainin...

A numerical mesh-free model applied to a strong formulation for simulating elasto-plastic structures with contact is developed in the context of large deformation. This numerical mesh-free model is based on the Asymptotic Numerical Method (ANM) which is used in the meshless collocation framework to extend its application field to elasto-plastic problems with contact. The efficiency of this model is to take into account of large deformations and to avoid the meshing distortion problem. According to (ANM) techniques, the development in Taylor series is performed to obtain a sequence of linear systems to be solved. These linear systems are then discretized by a collocation meshless approach by using the Moving Least Squares (MLS) functions and a continuation method is adopted to evaluate the solution. The unilateral contact problem is identified to boundary conditions which are replaced by force-displacement relations through a regularization technique. The performance of the proposed approach is tested on several elasto-plastic bi-dimensional examples without and with contact. The obtained results are compared to those computed by the Newton–Raphson method.

The aim of the present study was to obtain an oil/water (O/W) nanoemulsion (NE) containing garden savory (Satureja hortensis) essential oil (EO) and evaluating its herbicidal activity against Amaranthus retroflexus and Chenopodium album. Gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) were employed to determine the chemical composition of the EO. Carvacrol (55.6%) and γ-terpinene (31.9%) were the major EO components. Low energy method was applied, allowing achievement of EO nanodroplets. The NE also presented low polydispersity, and the mean droplet was below 130nm even after storage for 30d. Laboratory tests showed that the NE at different concentrations (100, 200, 400, 800, and 1000μL.L-1) significantly (P≤0.05) reduced the germination indices and the seedling's growth in dose-response. The inhibitory effect was the greatest at 800μL.L-1 NE. Overall, root length was more inhibited as compared to shoot length. Post-emergence application of NE at different concentrations (1000, 2000, 3000, 4000 and 5000μL.L-1 of EO) on 2-4 true leaves' stage of the weeds caused significant (P≤0.05) decrease in the growth factors in dose-dependent manner. Complete lethality was observed by 4000μL.L-1 NE sprayed on the weeds. Spraying of NE significantly (P≤0.05) reduced chlorophyll content in the tested weeds. Increasing in relative electrolyte leakage (REL) 1 and 5d after treatment represented significant cell membrane disruption and increased cell membrane permeability. Transmission electron microscope (TEM) pictures confirmed NE droplet size and demonstrated membrane destruction. The study approved that the NE of S. hortensis EO has herbicidal properties as it has high phytotoxic effect, and interferes with the germination, growth and physiological processes of the weeds. The production of NE from S. hortensis EO is a low energy method that offers a promising practical natural herbicide for weed control in organic agricultural systems.

The safety and efficacy of oral azithromycin and topical adapalene are well documented. In this study, concomitant use of oral azithromycin pulse therapy and daily topical adapalene in the treatment of acne vulgaris is assessed. A total of 37 patients fulfilled the inclusion criteria were enrolled. Azithromycin, 500 mg orally once daily first 3 days of 10 days' cycle for 9 cycle & topical Adapalene (0.5%) at night. Patients evaluated at 4 weeks' interval by using Michaelsson acne severity index. The overall assessment was made by percent reduction of acne lesions and severity score. At the end of 12 weeks' treatment 99.8% of comedones, 98.7% papular lesion, 94.3% pustular lesion and 88.8% infiltrated lesion were cleared. Only 2.9% cystic lesion responded to the regimens. Percent reduction of Michaelsson acne severity index was 87%, which was statistically highly significant. Overall assessment revealed acne lesion cleared in 22% cases, excellent improvement observed in 65% and 13% showed good response. Adverse effect was minimal. So, azithromycin pulse therapy and topical adapalene is indeed effective and safe in the treatment of acne vulgaris.Medicine Today 2016 Vol.28(2): 52-56

Grains and milling products constitute a major part of the daily diet of human and animal. The primary factor in grains and by products losses is the depredation of stored-product beetles. The objective of this trial was the evaluation of insecticidal and repellent activity of essential oils (EOs) from three Satureja spp (S. khuzestanica, S. rechingeri and S. bachtiarica) which grow wild in Iran, against the red flour beetle, Tribolium castaneum (Coleoptera: Tenebrionidae), known as one of the most common stored-product pests worldwide. Methodology EOs were extracted from aerial parts of three Satureja spp using a Clevenger type apparatus. Their chemical compositions were analyzed by gas chromatography–mass spectrometry (GC/MS). Results Results indicated that phenolic compounds, such as thymol and carvacrol, are the main constituents of the EOs. Insecticidal activity on the T. castaneum adult was evaluated by direct contact and fumigation bioassays. S. khuzestanica EO was the most efficient with the lowest estimated LD50 and LC50 as 20.11 μg/adult 2.51 mg/L air, respectively. All the tested EOs were strongly repellent to the T. castaneum adult at the tested concentration (1% v/v). Similarly, S. khuzestanica oil at 1% (v/v) showed the highest repellent activity (98% to 100%) after 4 h of exposure. Conclusion Considering the potential toxicity and repellency of the mentioned Satureja spp EOs to the red flour beetle, future studies could investigate the practical application of this potential bio-insecticide for the control of this pest.

In order to produce an autotetraploid population of anise hyssop (Agastache foeniculum L.), different concentrations of antimitotic agents including colchicine (0, 5000, 12,500 and 17,500 μM), oryz...

Literature available have already discussed in detail about motivations and perceived risks of international medical travelers in terms to their decision making, however, literature largely failed to discuss differences in motivations and the perceived risks of international medical travelers’ based on their countries of origin. Literature in leisure travel has already explained the influence of country of origin on motivation and perceived risk of travelers and their influence on visit intentions. The aim of the research study was to extensively review the literature and find out the differences in motivations and perceived risks among international medical travelers belong to developed regions and less developed regions of the world. The study also aimed to find out that in the context of categorization of intentions in psychology literature what type of intentions international patients may acquire based on the socio-economic conditions of their countries. Findings of rigorous literature review...

The aim of this paper is to present results of testing class F fly-ash and its potential application for oil and gas cementing applications. The main challenge in applications of these material is due to lack of research in understanding how these materials react in downhole conditions. Therefore, the methodology followed in this paper is based on experiments to understand geopolymer reactions with activator(s) and second compare some of their properties such as morphology and shear bond strength with Portland cement samples. Furthermore, we investigate the effects of chemical changes of alkaline activators on the shear bond and compressive strength and to analyze the microstructure and morphology of the slurry through SEM (Scan Electron Microscopy), and EDS (Energy Dispersive Spectroscopy). Experimental workflow includes testing several mix designs of geopolymers with different molarity. Observations from experiments confirmed increase in the specimen strength as the molarity increases. In addition, the analysis of the microstructure through SEM and EDS indicated that the Al and Si had considerable influence on the structure of the slurry. Further, we present results for shear bond tests conducted on two different pipe surfaces. Test results showed geopolymers have potentials to be applied for cementing pourposes with good morphology and shear bond strength Albeit, mix design plays a key role where excessive plasticizer concentration is determental to their performance. Additionally, an increase in Shear Bond Strength of fly ash-based geopolymer with a molar concentration of NaOH from 8 M to 10 M.

In this paper, we propose a new explicit analytical formula of the critical buckling load of double-walled carbon nanotubes (DWCNT) under axial compression. This formula takes into account van der Waals interactions between adjacent tubes and the effect of terms involving tube radii differences generally neglected in the derived expressions of the critical buckling load published in the literature. The elastic multiple Donnell shells continuum approach is employed for modelling the multi-walled carbon nanotubes. The validation of the proposed formula is made by comparison with a numerical solution. The influence of the neglected terms is also studied.

Geopolymers are a new class of binder materials suitable for applications in civil industry and Oil and Gas well cementing. Although these materials are widely applied in civil industry applications, they still need more research and development before they can be fully applied for Oil and Gas well cementing. Specifically, these materials have potential to reduce wellbore isolation problems reported by use of ordinary Portland cement (OPC). The study here first presents a comprehensive literature study of geopolymers and results of laboratory testing of class Fly ash geopolymer mixtures under various experimental conditions. We conducted a sensitivity analysis of various factors on specimen's strength as well as selection of plasticizer type and dosage, the effect of Sodium Hydroxide molarity, the effect of shear mixing and rate, mixing time, and effects of solid to liquid ratio. Study results show a strong impact of temperature and curing time on geopolymer mixture's strength whereas mixing condition were not found as a significant factor. Finally, this paper investigates the effect of drilling fluid's contamination on the performance of geopolymers when compared with ordinary Portland cement.

Tecomella undulata is an ecologically and economically important tree in arid areas of southwestern Asia. It has important ornamental and medicinal uses. In this study, aqueous extracts from roots, leaves, inner stem barks and flowers of T. undulata were studied for their allelopathic effects on seed germination and early seedling growth of four important monocotyledonous and dicotyledonous ornamental plants. The flower and root extracts of T. undulata significantly (P

Understanding the mode of action of allelochemicals, as the cause of oxidative stress and induction of antioxidant mechanism, is one of the challenging aspects in allelopathic studies. Accordingly, the aim of the present study was to analyze the effect of allelochemical stress, induced by peppermint water extract (WE), on radish (Raphanus sativus L.) growth. The peppermint WE concentrations were 0, 2, 4, 6, 8, and 10% (v/v). Some phenolic compounds of the peppermint WE determined by HPLC were trans-ferulic acid (10.8 mg/g), hesperidin (9.3 mg/g), ellagic acid (6.8 mg/g), and sinapic acid (4.2 mg/g). The maximum inhibitory effect of peppermint extract on germination and growth was obtained at 8% WE concentration. The results showed that the compounds in the extract of peppermint had significant effect on the amount of proline (PRO), soluble sugars and total phenols, as well as on the activity of antioxidant enzymes, and relative membrane permeability (RMP) (P

This research was aimed at determining the effects of multi-walled carbon nanotubes (MWCNTs) on seed germination, seedling growth parameters and secondary metabolite (SM) production of Thymus daenensis in vitro. Seeds were aseptically cultured in Murashige and Skoog medium (MS) with various concentrations of MWCNTs (0, 125, 250, 500, 1000 and 2000 μg ml−1). Seed germination and morphological changes in seedlings were measured. The measurements were aimed at quantifying the total phenolic contents (TPC) and flavonoids (TFC), antioxidant activities and the activity of polyphenol oxidase (PPO), l -phenylalanine ammonia-lyase (PAL), dehydrogenase (DHA) and peroxidase enzyme (POD) of the seedling extract. Seedling biomass and seedling height grew significantly as the MWCNTs level increased. The biomass and height peaked at 250 μg ml−1 (0.41 ± 0.01 gr FW, 5.99 ± 0.55 cm) and then rapidly decreased to 0.040 ± 0.1 gr FW and 1.42 ± 0.24 cm in response to 1000 μg ml−1, 30 days after the treatment. Additionally, SM and the analyses of enzyme activity revealed that the highest amounts of TPC (6.70 ± 0.06 mg GAE g−1 DW), TFC (8.19 ± 0.01 mg QUE g−1 DW), antioxidant activities (73.88 ± 0.47%) and maximum PAL activity (1.25 ± 0.08 mM cm g−1 FW) were detected in plants grown on MS media fortified with 250 μg ml−1 MWCNTs. The results reveal that MWCNTs in low doses (250 μg ml−1) can encourage the production of biomass, elicit more SM from seedlings and enhance the biosynthesis of antioxidants. TEM images showed that MWCNTs could cross the plant cell wall and enter the cellular cytoplasm.

Background: New scolicidal agents and novel therapeutic drugs are essential for better management of the zoonotic infection, hydatid disease. This study evaluated the effect of a nanoemulsion (NE) of Satureja hortensis essential oil (SHEO) on protoscoleces and germinal layer of hydatid cysts. Methods: This study was conducted from July to October 2016 in Shiraz University, Shiraz, Iran. Gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) were performed to identify the main components of SHEO. To determine the scolicidal power of the NE of SHEO, live protoscoleces of hydatid cysts were exposed to two concentrations (1 and, 2 mg/mL) of the NE and incubated at 37 °C for 10 and 20 min. To evaluate the anti-hydatid effect of the NE of SHEO, the collected hydatid cysts from the abdominal cavities of the experimentally infected mice were immersed in the NE (0.5 mg/ml) and incubated at 22 °C for 24 h. Results: Carvacrol and γ-terpinene were the major components of the SHEO. NE of SHEO at the concentrations of 1 and 2 mg/mL showed 100% scolicidal power after 20 and 10 min respectively. Exposure of the hydatid cysts to the NE of SHEO resulted in crumpling of their germinal layer and detachment of this layer from the laminated layer. Conclusion: NE of SHEO showed a strong scolicidal activity as well as a profound lethal effect on the germinal layer of hydatid cysts. Accordingly, this product may be used as a natural scolicidal agent in hydatid cyst surgery. Furthermore, it may be used as a therapeutic tool for treatment of hydatid disease.

This paper aims to investigate, in large displacement and torsion context, the nonlinear dynamic behavior of thin-walled beams with open cross section subjected to various loadings by high-order implicit solvers. These homotopy transformations consist to modify the nonlinear discretized dynamic problem by introducing an arbitrary invertible pre-conditioner \begin{document}$ [K^\star] $\end{document} and an arbitrary path following parameter. The nonlinear strongly coupled equations of these structures are derived by using a \begin{document}$ 3D $\end{document} nonlinear dynamic model which accounts for large displacements and large torsion without any assumption on torsion angle amplitude. Coupling complex structural phenomena such that warping, bending-bending, and flexural-torsion are taken into account. Two examples of great practical interest of nonlinear dynamic problems of various thin-walled beams with open section are presented to validate the efficiency and accuracy of high-order implicit solvers. The obtained results show that the proposed homotopy transformations reveal a few number of matrix triangulations. A comparison with Abaqus code is presented.

Reflective cracking at transverse joints is considered as a predominant distress in composite pavements. Various interlayers have been used previously to prevent or retard reflective cracking. Engineered cementitious composite (ECC) is a special type of high-performance fiber-reinforced cementitious material that is expected to perform better as an interlayer due to its higher tensile strength and ductility. This study aims to evaluate the effectiveness of ECC as an interlayer system experimentally. A laboratory test protocol was designed to simulate repeated traffic loads to measure the fatigue performance of ECC interlayer system using digital image correlation (DIC) technique. It was found that the composite pavement specimens with ECC interlayer provided significantly higher fatigue life as compared to the control specimens without interlayer. This result indicates that ECC could be used as a potential effective interlayer system to retard or mitigate reflective cracking.

Rosemary is one of the most important medicinal plants. In order to study the effect of plant growth promoting rhizobacteria (PGPR), Azolla compost and Azolla biochar on dry matter, nutrient uptake, physiological parameters and essential oil of rosemary, a greenhouse experiment was conducted in a completely randomized design with 6 replications. Treatments consisted of T1 (control), T2 (1% (1 g 100 g-1 dry soil) Azolla compost), T3 (1% Azolla biochar), T4 (PGPR (P. fluorescens)), T5 (1% compost + PGPR) and T6 (1% biochar + PGPR). Results indicated a significant enhancement of dry matter, nutrient uptake, photosynthetic pigments, carbohydrate, flavonoid and essential oil contents of rosemary influenced by organic fertilizers compared to control, particularly with co-appli­cation of PGPR + compost or biochar. Proline content decreased in all treatments in comparison with control. Results indicated positive impacts of PGPR, compost and boichar of Azolla on rosemary production by increasing nutrient uptake and protecting chlorophyll from degradation and enhancing its content in leaves. DOI: 10.5073/JfK.2019.01.01, https://doi.org/10.5073/JfK.2019.01.01, Journal of Cultivated Plants, Bd. 71 Nr. 1 (2019)

Purpose Methods and materials Results Conclusion Personal information and conflict of interest References, Purpose: Background: Multidisciplinary team (MDT) meetings are well established as a core component of medical care and are mandatory within NHS hospitals providing cancer cervices. In England, it is estimated that 55,000 MDT meetings take place each year...

Treatment of skin injuries is still facing major challenges, such as chronicity and infections, particularly those caused by multi-drug resistance pathogens. An effective treatment of such wounds should accelerate the wound healing process while preventing bacterial contamination. Here, a novel core–shell nanofiber mat was fabricated comprising gelatin/polyvinyl alcohol (as a core) and aloe vera/arabinose/polyvinylpyrrolidone (as a shell) for accelerating the healing process of bacteria-infected wounds. Trachyspermum Ammi (Ajwain) essential oil (EO), as a potent and natural antimicrobial agent against microorganisms, was incorporated into the core of nanofiber mats using coaxial electrospinning. The microscopy images demonstrated the successful fabrication of the core–shell structure with a uniform fiber size of 564 ± 106.35 nm. Moreover, Ajwain EO-loaded nanofiber mat (core–shell/EO) provided excellent antimicrobial activity and antioxidant ability. The in vitro and ex vivo release of Ajwain EO from the fabricated nanofiber mat corroborated a prolonged release profile. Furthermore, in vivo antibacterial activity, wound closure, and histomorphological examinations showed the high efficacy of the core–shell/EO mat in the treatment of Staphylococcus aureus-infected full-thickness rat wounds compared to standard control treatment with a gauze. Overall, these results represent the core–shell/EO mat's potential as a newly developed wound dressing for bacteria-infected full-thickness skin injuries.

An experimental investigation was conducted to determine the effect of internal curing of natural lightweight aggregates (LWAs) on the shrinkage, mechanical properties, and durability of high-performance concrete (HPC). Conventional aggregates were partially substituted with prewetted coarse and fine LWA at dosages of 5, 10, and 20% by volume. The early age autogenous shrinkage and drying shrinkage of the HPC mixtures were monitored for up to 180 days. The investigated properties of the HPC mixtures included compressive strength, modulus of elasticity, and splitting tensile strength at 28 days, as well as rapid chloride permeability and water absorption. The results revealed that, at a replacement level of 20% for both coarse and fine aggregates, the reduction in autogenous shrinkage of the HPC mixtures was approximately 118% at 28 days and 65% at 18 days. Furthermore, the test results indicated that the autogenous shrinkage measured between 15 h and 7 days after casting was reduced by approximately 75%. Fine LWAs were more effective in reducing autogenous shrinkage than coarse LWAs. This was attributed to the small particles, which allowed a good distribution of the water-filled internal curing within the cement matrix. It was also found that using up to 20% LWA could modify the 28-day autogenous shrinkage of HPC by reducing the cube compressive strength up to 70 MPa as compared to 86 MPa for the control mixture. In addition, the obtained strength values of the concrete mixes were found to be within the acceptable range specified by the ACI standard to be categorized as HPC. The findings of the study revealed that the utilization of LWA is feasible as an internal curing method for decreasing the volume changes, particularly at the early ages, and for avoiding the formation of cracks in HPC.

In this research mechanical characteristics of roller compacted geopolymer concrete (RCGPC) and roller compacted cement concrete (RCC) using 100% recycled concrete aggregate (RCA) were investigated and compared. The surface morphology and formation of chemical compounds of the selected RCGPC composite mixtures were also analyzed using Scanning electron microscopy (SEM), X-Ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR). It was revealed from the investigation that the compressive strength of the RCGPC material was dependent on the mixture variables like the molar concentration of sodium hydroxide (NaOH), sodium silicate (Na2SiO3) to NaOH ratio (alkali activator), curing time and temperature, and dosage of fly ash. The experimental results depicted that the compressive strength, modulus of elasticity, and flexural strength of RCGPC composites varied in the range of 7.5 to 27.6 MPa, 16 to 46.8 GPa, and 2.1 to 3.8 MPa, respectively. While RCC using 12% ordinary cement yielded a compressive strength, modulus, and flexural strength of 18.9 MPa, 32.7 GPa, and 2.1 MPa, respectively. SEM, XRD, and FTIR analysis also revealed the formation of geopolymer compounds and their relative presence in the new composite based on the mixture variables. It is believed that the developed RCA based roller compacted geopolymer concrete could be used as an alternative material for pavement construction.

Wounds are prone to bacterial infections, which cause a delayed healing process. Regarding the emergence of bacterial resistance to common antibiotics, using natural antimicrobial agents can be beneficial. Chitosan is a biological polymer, which has shown partial antioxidant and antimicrobial activities. In this study, core-shell nanofibrous scaffolds composed of chitosan (CS)/polyvinyl alcohol (PVA) as the core and polyvinylpyrrolidone (PVP)/ maltodextrin (MD) as the shell were developed. Satureja mutica (S. mutica) or Oliveria decumbens (O. decumbens) essential oil (EO) was encapsulated into the core of the produced scaffolds. The broth microdilution analysis showed significant antimicrobial activity of the EOs. The SEM analysis indicated that the unloaded and loaded core-shell scaffolds with S. mutica or O. decumbens EO had a uniform, beadless structure with fiber mean diameters of 210 ± 50, 250 ± 45, and 225 ± 46 nm, respectively. The CS/PVA-PVP/MD and CS/PVA/EO-PVP/MD scaffolds indicated suitable mechanical properties. The addition of the studied EOs enhanced the antioxidant activity of the scaffolds. The antimicrobial test of produced scaffolds showed that loading of 10% S. mutica or O. decumbens EO could broaden the microbicidal activity of the CS/PVA-PVP/MD scaffolds. These results revealed that the CS/PVA/EO-PVP/MD nanofibrous scaffolds are promising candidates for wound dressing.

In this paper, the linear bending response of straight, thin to moderately thick functionally graded (FG) composite beams reinforced with graphene oxide powder (GOP) and subjected to two types of static mechanical loads, with various boundary conditions is investigated using a meshfree collocation method based on multiquadric radial basis functions. The weight fractions of the GOP are considered to vary continuously through the thickness direction of the composite beams. To determine the effective Young's modulus of the FG-GOP reinforced composite beams, a modified Halpin–Tsai model is used, whereas the rule of mixture is adopted to estimate the equivalent Poisson's ratio. The first-order shear deformation (FSDT) beam theory is adopted to model the functionally graded graphene oxide powder (FG-GOP) reinforced composite beams. The static equilibrium equations and associated boundary conditions of the FG-GOP reinforced composite beams are obtained by using the principle of minimum potential energy. The governing equations are rewritten in a matrix-vector strong form and discretized using the multiquadric radial basis functions. Various comparisons studies are performed to demonstrate the robustness and accuracy of the proposed numerical model. Parametric studies are conducted to examine the effects of length-to-thickness ratio, GOP distribution patterns, weight fraction, and size of GOP, types of loads, and boundary conditions on the bending behavior of the FG-GOP reinforced composite beams.

This paper analyses the various configuration for the emergency ventilation system consisting of an air curtain and exhaust fan to manage the dispersion of heat and toxicity inside an enclosure for different fire scenarios. Employing this ventilation system is helpful to secure an escape route or extinguishing the fire. The air curtain discharge velocity is 10, 18, and 30 m / s and its discharge angle is set to be 0 ° , 15 ° , and 30 ° . Three values of 0.5, 1, and 2 m 3 / s are considered for the exhaust flow rate. Computational Fluid Dynamics simulations have been conducted with a steady laminar flamelet model and buoyant standard k − e turbulence model to assess the performance of the air curtain and emergency exhaust system for smoke confinement. Evaluation of an optimized state of the emergency ventilation system is provided by the Taguchi method due to computational limitations in solving various cases for the ventilation system configuration. Results show that for each location and heat release rate of fire, it is possible to manage heat, CO, and CO2 dispersion with the adjustment air curtain parameters and emergency exhaust system. Finally, the optimum state of the system is reported for each scenario, and the temperature and concentration of toxic gas have been compared. Results show that for the 200 kW fire, 2 m 3 / s exhaust flow rate with air curtain discharge velocity of 18 m/s and 15 ° would be adequate. However, 500 kW fire requires 30 m/s with 30 ° discharge velocity to contain the fire inside the compartment.