Search results for: Cement Resistant to Sulfate (CRS)

Authors: Samaneh Soroush, Tommy Golczynski, Tony Spratt

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One of the new technologies for CO₂ capture, storage, and utilization (CCSU) is forming clathrate hydrate. This technology has some unknowns and challenges that make it difficult to apply in the real world. The low formation rate is one of the main difficulties of CO₂ hydrate. In this work, the effect of different promotors on the hydrate formation rate has been studied. Two surfactants, sodium dodecyl sulfate (SDS), tetra-n-butylammonium bromide (TBAB), and cyclopentane (CP) as a thermodynamic promotor and their combination have been used for the experiments. The results showed that the SDS is a powerful kinetic promotor and its combination with CP helps to convert more CO₂ to hydrate in a short time.

Keywords: carbon capture, carbon dioxide, hydrate, promotor

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Authors: E. Samain, T. Aussenac, D. van Tuinen, S. Selim

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Plant growth promoting rhizobacteria are known as potential biofertilizers and plant resistance inducers. The present work aims to study the durability of the resistance induced as a response to wheat seeds inoculation with PB2 and its influence by Z. tritici strains. The internal and external roots colonization have been determined in vitro, seven days post inoculation, by measuring the colony forming unit (CFU). In planta experimentations were done under controlled conditions included four wheat cultivars with different levels of resistance against Septoria Leaf Blotch (SLB) and four Z. tritici strains with high aggressiveness and resistance levels to fungicides. Plantlets were inoculated with PB2 at sowing and infected with Z. tritici at 3 leaves or tillering growth stages. The infection level with SLB was evaluated at 17 days post inoculation using real-time quantitative polymerase chain reaction (PCR). Results showed that PB2 has a high potential of wheat root external colonization (> 10⁶ CFU/g of root). However, the internal colonization seems to be cultivar dependent. Indeed, PB2 has not been observed as endophytic for one cultivar but has a high level of internal colonization with more than 104 CFU/g of root concerning the three others. Two wheat cultivars (susceptible and moderated resistant) were used to investigate PB2-induced resistance (PB2-IR). After the first infection with Z. tritici, results showed that PB2-IR has conferred a high protection efficiency (40-90%) against SLB in the two tested cultivars. Whereas the PB2-IR was effective against all tested strains with the moderate resistant cultivar, it was higher with the susceptible cultivar (> 64%) but against three of the four tested strains. Concerning the durability of the PB2-IR, after the second infection timing, it has been observed a significant decrease (10-59%) depending strains in the moderate resistant cultivar. Contrarily, the susceptible cultivar showed a stable and high protection level (76-84%) but against three of the four tested strains and interestingly, the strain that overcame PB2-IR was not the same as that of the first infection timing. To conclude, PB2 induces a high and durable resistance against Z. tritici. The PB2-IR is pathogen strain, plant growth stage and genotype dependent. These results may explain the loss of the induced resistance effectiveness under field conditions.

Keywords: induced resistance, Paenibacillus sp. strain B2, wheat genotypes, Zymoseptoria tritici

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Authors: S. J. Sirima, C. Thirawan, R.Puntharikorn, K. Ungsumalin, J. Kaemwich

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Acinetobacter spp. is a gram negative bacterium causing the high incidence of multi-drug resistance in patients admitted to an intensive care unit. A hundred isolates of Imipenem-resistant Acinetobacter spp. isolated from patients admitted at tertiary health care center, Northeastern region, Ubon Ratchathani, Thailand, were subjected to modified Hodge test and combined disc test in order to evaluate the production of carbapenemases. The results revealed that about 35% of isolates were found to be carbapenemases producers. In addition, multiplex polymerase chain reactions were performed to detect blaOXA-like genes. It showed that 92% of isolates possess blaOXA-51-like and blaOXA-23-like genes. However, blaOXA-58-like gene was detected in only 8 isolates. No detection of blaOXA-24-like gene was observed in all isolates. In conclusion, an ability to produce carbepenemases would be an important mechanism of multi-drug resistance among clinical isolates of Acinetobacter spp. at tertiary health care center, Northeastern region, Ubon Ratchathani, Thailand. Furthermore, it was likely that the class D carbapenemases genes, blaOXA-51-like and blaOXA-23-like, might contribute to imipenem-resistance exhibiting among isolates.

Keywords: Acinetobacter spp., blaOXA-like genes, carbapenemases, tertiary health care center

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Authors: Danylo Brindak, Viktor Liashko, Olexander Chepurniy

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Despite considerable experience in implementation of the best international approaches and services within response to epidemy of multi-drug resistant tuberculosis, the results of situation analysis indicate the presence of faults in this area. In 2014, Ukraine (for the first time) was included in the world’s five countries with the highest level of drug-resistant tuberculosis. The effectiveness of its treatment constitutes only 35% in the country. In this context, the increase in allocation of funds to control the epidemic of multidrug-resistant tuberculosis does not produce perceptible positive results. During 2001-2016, only the Global Fund to fight AIDS, Tuberculosis, and Malaria allocated to Ukraine more than USD 521,3 million for programs of tuberculosis and HIV/AIDS control. However, current conditions in post-Semashko system create little motivation for rational use of resources or cost control at inpatient TB facilities. There is no motivation to reduce overdue hospitalization and to target resources to priority sectors of modern tuberculosis control, including a model of care focused on the patient. In the presence of a line-item budget at medical institutions, based on the input factors as the ratios of beds and staff, there is a passive disposal of budgetary funds by health care institutions and their employees who have no motivation to improve quality and efficiency of service provision. Outpatient treatment of tuberculosis is being implemented in Ukraine since 2011 and has many risks, namely creation of parallel systems, low consistency through dependence on funding for the project, reduced the role of the family doctor, the fragmentation of financing, etc. In terms of reforming approaches to health system financing, which began in Ukraine in late 2016, NGO Infection Control in Ukraine conducted piloting of a new, motivating method of remuneration of employees in primary health care. The innovative aspect of this funding mechanism is cost according to results of treatment. The existing method of payment on the basis of the standard per inhabitant (per capita ratio) was added with motivating costs according to results of work. The effectiveness of such treatment of TB patients at the outpatient stage is 90%, while in whole on the basis of a current system the effectiveness of treatment of newly diagnosed pulmonary TB with positive swab is around 60% in the country. Even though Ukraine has 5.24 TB beds per 10 000 citizens. Implemented pilot model of ambulatory treatment will be used for the creation of costs system according to results of activities, the integration of TB and primary health and social services and their focus on achieving results, the reduction of inpatient treatment of tuberculosis.

Keywords: health care reform, multi-drug resistant tuberculosis, outpatient treatment efficiency, tuberculosis

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Authors: Li Guoyou, Zhang Tao, Ji Wenzhan, Huo Liang, Lin Xiqiang, Zhang Nan

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The three dimensional (3D) printing technology has undergone rapid development in the last few years and it is possible to print engineering structures. 3D printing buildings use wastes from constructions, industries and mine tailings as “ink”, and mix it with property improved materials, such as cement, fiber etc. This paper presents a study of the Thermodynamic performance of 3D printed walls using cement and steel slag powder. Analyses the thermal simulation regarding 3D printed walls and solid brick wall by the way of the hot-box methods and the infrared technology, and the results were contrasted with theoretical calculation. The results show that the excellent thermodynamic performance of 3D printed concrete wall made it suitable as the partial materials for self-thermal insulation walls in residential buildings. The thermodynamic performance of 3D printed concrete walls depended on the density of materials, distribution of holes, and the filling materials. Decreasing the density of materials, increasing the number of holes or replacing the filling materials with foamed concrete could improve its thermodynamic performance significantly. The average of heat transfer coefficient and thermal inertia index of 3D printed steel slag powder concrete wall all better than the traditional solid brick wall with a thickness of 240mm.

Keywords: concrete, 3D printed walls, thermodynamic performance, steel slag powder

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Authors: Oktira Roka Aji, Maelita R. Moeis, Ihsanawati, Ernawati A. Giri-Rachman

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Globally, tuberculosis (TB) remains a leading cause of death. The emergence of multidrug-resistant strains and extensively drug-resistant strains have become a major public concern. One of the potential candidates for drug target is the cytoplasmic domain of PhoR Histidine Kinase, a part of the Two Component System (TCS) PhoR-PhoP in Mycobacterium tuberculosis (Mtb). TCS PhoR-PhoP relay extracellular signal to control the expression of 114 virulent associated genes in Mtb. The 3D structure of PhoR cytoplasmic domain is needed to screen novel drugs using structure based drug discovery. The PhoR cytoplasmic domain from Mtb H37Rv was overexpressed in E. coli BL21(DE3), then purified using IMAC Ni-NTA Agarose his-tag affinity column and DEAE-ion exchange column chromatography. The molecular weight of the purified protein was estimated to be 37 kDa after SDS-PAGE analysis. This sample was used for pre-crystallization screening by applying sitting drop vapor diffusion method using Natrix (HR2-116) 48 solutions crystal screen kit at 25ºC. Needle-like crystals were observed after the seventh day of incubation in test solution No.47 (0.1 M KCl, 0.01 M MgCl2.6H2O, 0.05 M Tris-Cl pH 8.5, 30% v/v PEG 4000). Further testing is required for confirming the crystal.

Keywords: tuberculosis, two component system, histidine kinase, needle-like crystals

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Authors: Francesca Lombardi, Francesca Rosaria Augello, Benedetta Cinque, Maria Grazia Cifone, Paola Palumbo

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Glioblastoma multiforme (GBM) is a high-grade primary brain tumor refractory to current forms of treatment. The survival benefits of patients with GBM remain unsatisfactory due to the intrinsic or acquired resistance to temozolomide (TMZ), an alkylating agent, used as the first-line chemotherapeutic drug to treat GBM patients. Its cytotoxic effect is visualized by the induction of O6-methylguanine (O6MeG) within DNA. Cyclooxygenase-2 (COX-2), an inflammation-associated enzyme, has been implicated in tumorigenesis and progression of GBM, its inhibition shows anticancer activities. In the present study, it was verified if the combination of a COX-2 selective inhibitor, NS398, with TMZ could counteract the TMZ resistance. In particular, the effect of NS398 mixed with TMZ was investigated in the GBM TMZ-resistant cell line, T98G. Cells were pretreated with NS398 (100µM, 24 hours) and then exposed to TMZ alone (200µM), NS398 alone, or both for 72 hours, after which cell growth rate and cycle phases, as well as apoptosis level, were evaluated. Coadministration of NS398 and TMZ caused a significant decrease in cell growth and a progressive increase of dead cells detected by trypan blue staining. Moreover, a significant level of apoptotic cell percentage and alteration of cell cycle phases were observed in T98G treated with TMZ-NS398 combination when compared to untreated cells or TMZ-treated cells. TMZ-resistant tumors, as GBM, express elevated levels of DNA repair enzyme O6-methylguanine-DNA methyltransferase (MGMT). The mixture drastically reduced MGMT expression in the TMZ-resistant cell line T98G, known to express high levels of MGMT basically. Moreover, while TMZ alone did not influence the COX-2 protein expression, the combination successfully reduced it. In conclusion, these results demonstrated that NS398 enhanced the efficacy of TMZ through cell number reduction, apoptosis induction, and decreased MGMT levels, suggesting the ability of drug combination to reduce the chemoresistance. This drug combination deserves attention and could be considered as a promising therapeutic strategy for GBM patients.

Keywords: COX-2, COX-2 inhibitor, glioblastoma, NS398, T98G, temozolomide

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Authors: Guna Raj Dhungana, Roshan Nepal, Apshara Parajuli, , Archana Maharjan, Shyam K. Mishra, Pramod Aryal, Rajani Malla

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Introduction: Klebsiella pneumoniae is a well-known opportunistic human pathogen, primarily causing healthcare-associated infections. The global emergence of carbapenemase-producing K. pneumoniaeis a major public health burden, which is often extensively multidrug resistant.Thus, because of the difficulty to treat these ‘superbug’ and menace and some term as ‘apocalypse’ of post antibiotics era, an alternative approach to controlling this pathogen is prudent and one of the approaches is phage mediated control and/or treatment. Objective: In this study, we aimed to isolate novel bacteriophage against carbapenemase-producing K. pneumoniaeand characterize for potential use inphage therapy. Material and Methods: Twenty lytic phages were isolated from river water using double layer agar assay and purified. Biological features, physiochemical characters, burst size, host specificity and activity spectrum of phages were determined. One most potent phage: Phage TU_Kle10O was selected and characterized by electron microscopy. Whole genome sequences of the phage were analyzed for presence/absence of virulent factors, and other lysin genes. Results: Novel phage TU_Kle10O showed multiple host range within own genus and did not induce any BIM up to 5th generation of host’s life cycle. Electron microscopy confirmed that the phage was tailed and belonged to Caudovirales family. Next generation sequencing revealed its genome to be 166.2 Kb. bioinformatical analysis further confirmed that the phage genome ‘did not’ contain any ‘bacterial genes’ within phage genome, which ruled out the concern for transfer of virulent genes. Specific 'lysin’ enzyme was identified phages which could be used as 'antibiotics'. Conclusion: Extensively multidrug resistant bacteria like carbapenemase-producing K. pneumoniaecould be treated efficiently by phages.Absence of ‘virulent’ genes of bacterial origin and presence of lysin proteins within phage genome makes phages an excellent candidate for therapeutics.

Keywords: bacteriophage, Klebsiella pneumoniae, MDR, phage therapy, carbapenemase,

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Authors: N. Bakradze, T. Dumbadze, N. Gagelidze, L. Amiranashvili, A. D. L. Batako

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Cereals are considered as a strategic product in human life and it demand is increasing with the growth of world population. There is always shortage of cereals in various areas of the globe. For example, Georgia own production meets only 15-20% of the demand for grain, despite the fact that the country is considered one of the main centers of wheat origin. In Georgia, there are 14 types of wheat and more than 150 subspecies, and 40 subspecies of common wheat. Increasing wheat production is important for the country. One of the ways to solve the problem is to develop and implement new, environmentally and economically acceptable technologies. Such technologies include pre-sowing treatment of seed with a laser and associative nitrogen-fixing of the Azospirillum brasilensse bacteria. In the region there are Dika and Lomtagora which are among the most common in Georgia. Dika is a frost-resistant wheat, with a high ability to adapt to the environment, resistant to falling and it is sown in highlands. Dicka excellent properties are due to its strong immunity to fungal diseases; Dicka grains are rich in protein and lysine. Lomtagora 126 differs with its winter and drought resistance, and, it has a great ability to germinate. Lomtagora is characterized by a strong root system and a high budding capacity. It is an early variety, fall-resistant, easy to thresh and suitable for mechanized harvesting with large and red grains. The plant is moderately resistant to fungal diseases. This paper presents some preliminary experimental results where, a continuous CO2 laser at a power of 25-40 W/cm2 was used to radiate grains at a flow rate of 10-15 cm/sec. The treatment was carried out on grains of the Triticum aestivum L. var. of Lutescens (local variety name - Lomtagora 126), and Triticum carthlicum Nevski (local variety name - Dika). Here the grains were treated with Azospirillum brasilensse isolate (108-109 CFU / ml), which was isolated from the rhizosphere of wheat. It was observed that the germination of the wheat was not significantly influenced by either laser or bacteria treatment. In the case of the variety Lomtagora 126, when irradiated at an angle of 90°, it slightly improved the growth within 38 days of sawing, and in the case of irradiation at an angle of 90°+1, by 23%. The treatment of seeds with Azospirillum brazilense in both irradiated and non-irradiated variants led to an improvement in the growth of ssprouts. However, in the case of treatment with azospiril alone - by 22%, and with joint treatment of seeds with azospiril and irradiation - by 29%. In the case of the Dika wheat, the irradiation only led to an increase in growth by 8-9%, and the combine treatment of seeds with azospiril and irradiation - by 10-15%, in comparison with the control. Thus, the combine treatment of wheat of different varieties provided the best effect on the growth. Acknowledgment: This work was supported by Shota Rustaveli National Science Foundation of Georgia (SRNSFG) (Grant number CARYS 19-573)

Keywords: laser treatment, Azospirillum brasilensse, seeds, wheat varieties, Lomtagora, Dika

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Authors: Kotbia Labiod, Mohamed Mouldi Tlili

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The presence of different mineral salts in natural waters may precipitate and form hard deposits in water distribution systems. In this respect, we have developed numerous works on scaling by Algerian water with a very high hardness of 102 °F. The aim of our work is to study the influence of water dynamics and its composition on mineral salts on the precipitation of calcium carbonate (CaCO3). To achieve this objective, we have adopted two precipitation techniques based on controlled degassing of dissolved CO2. This study will identify the causes and provide answers to this complex phenomenon.

Keywords: calcium carbonate, controlled degassing, precipitation, scaling

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Authors: Sandra C. L. Dorea, Joann K. Whalen, Yixin Shao, Oumarou Savadogo

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The major challenge for industries that rely on fossil fuels in manufacturing processes or to provide goods and services is to lower their CO2 emissions, as the case for the manufacture of Portland cement. Feasible materials for this purpose can include agro-industrial or agricultural wastes, which are termed 'biosilica' since the silica was contained in a biological matrix (biomass). Corn cob (CC) has some characteristics that make it a good candidate as biosilica source: 1) it is an abundant grain crop produced around the world; 2) more production means more available residues is left in the field to be used. This work aims to evaluate the CC collected from different farms in Canada during the corn harvest in order to see if they can be used together as a biosilica source. The characterization of the raw CC was made in the physical, chemical, and thermal way. The moisture content, the granulometry, and the morphology were also analyzed. The ash content measured was 2,1%. The Thermogravimetric Analysis (TGA) and its Derivative (DTG) evaluated of CC as a function of weight loss with temperature variation ranging between 30°C and 800°C in an atmosphere of N2. The chemical composition and the presence of silica revealed that the different sources of the CC do not interfere in its basic chemical composition, which means that this kind of waste can be used together as a source of biosilica no matter where they come from. Then, this biosilica can partially replace the cement Portland making sustainable cementitious mixtures and contributing to reduce the CO2 emissions.

Keywords: biosilica, characterization, corn cob, sustainable cementitious materials

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Authors: B. M. Y. I. Basnayake, G. G. T. Nisansala, P. I. J. B. Wijewickrama, U. S. Weerathunga, K. W. M. Y. D. Gunasekara, N. K. Jayasekera, A. W. Kalupahana, R. S. Kalupahana, A. Silva- Fletcher, K. S. A. Kottawatta

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Antimicrobial resistance (AMR) has attracted significant attention worldwide as an emerging threat to public health. Understanding the role of livestock and wildlife with the shared environment in the maintenance and transmission of AMR is of utmost importance due to its interactions with humans for combating the issue in one health approach. This study aims to investigate the extent of AMR distribution among wild animals, livestock, and environment cohabiting in a rural ecosystem in Sri Lanka: Hambegamuwa. One square km area at Hambegamuwa was mapped using GPS as the sampling area. The study was conducted for a period of five months from November 2020. Voided fecal samples were collected from 130 wild animals, 123 livestock: buffalo, cattle, chicken, and turkey, with 36 soil and 30 water samples associated with livestock and wildlife. From the samples, Escherichia coli (E. coli) was isolated, and their AMR profiles were investigated for 12 antimicrobials using the disk diffusion method following the CLSI standard. Seventy percent (91/130) of wild animals, 93% (115/123) of livestock, 89% (32/36) of soil, and 63% (19/30) of water samples were positive for E. coli. Maximum of two E. coli from each sample to a total of 467 were tested for the sensitivity of which 157, 208, 62, and 40 were from wild animals, livestock, soil, and water, respectively. The highest resistance in E. coli from livestock (13.9%) and wild animals (13.3%) was for ampicillin, followed by streptomycin. Apart from that, E. coli from livestock and wild animals revealed resistance mainly against tetracycline, cefotaxime, trimethoprim/ sulfamethoxazole, and nalidixic acid at levels less than 10%. Ten cefotaxime resistant E. coli were reported from wild animals, including four elephants, two land monitors, a pigeon, a spotted dove, and a monkey which was a significant finding. E. coli from soil samples reflected resistance primarily against ampicillin, streptomycin, and tetracycline at levels less than in livestock/wildlife. Two water samples had cefotaxime resistant E. coli as the only resistant isolates out of 30 water samples tested. Of the total E. coli isolates, 6.4% (30/467) was multi-drug resistant (MDR) which included 18, 9, and 3 isolates from livestock, wild animals, and soil, respectively. Among 18 livestock MDRs, the highest (13/ 18) was from poultry. Nine wild animal MDRs were from spotted dove, pigeon, land monitor, and elephant. Based on CLSI standard criteria, 60 E. coli isolates, of which 40, 16, and 4 from livestock, wild animal, and environment, respectively, were screened for Extended Spectrum β-Lactamase (ESBL) producers. Despite being a rural ecosystem, AMR and MDR are prevalent even at low levels. E. coli from livestock, wild animals, and the environment reflected a similar spectrum of AMR where ampicillin, streptomycin, tetracycline, and cefotaxime being the predominant antimicrobials of resistance. Wild animals may have acquired AMR via direct contact with livestock or via the environment, as antimicrobials are rarely used in wild animals. A source attribution study including the effects of the natural environment to study AMR can be proposed as this less contaminated rural ecosystem alarms the presence of AMR.

Keywords: AMR, Escherichia coli, livestock, wildlife

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Authors: Mohammad Momeenul Islam, U. Johnson Alengaram, Mohd Zamin Jumaat, Iftekhair Ibnul Bashar

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Palm oil industry produces millions of tonnes of industrial wastes and these wastes create huge storage and environmental problems. In order to solve these problems various research works have been performed for past decades. The commonly available wastes are Oil palm shells (OPS) and Palm oil fuel ash (POFA). These materials have already acquired well recognition as alternate of conventional construction materials. OPS has been used as coarse aggregate and compressive strength was found up to 56 MPa for 56-day. It is said that 30 grade Oil Palm shell concrete (OPSC) is possible without adding any cementitious materials. The maximum modulus of elasticity for OPSC was found 18.6 GPa. The Oil palm shell concrete (OPSC) are used in country areas and nearby areas where the palm oil factories are located for houses, road-kerbs, drain blocks, etc. In case of superstructure like beams and slab are also produced by utilizing OPS. Many experimental works have been performed to establish POFA as a substituting binding material in replace of Ordinary Portland cement (OPC). Throughout the research it has been showed that up to 20% of cement by mass can be replaced by POFA. POFA is one of the most enriched pozzolanic materials. The main purpose of this review is to discuss the usage and opportunity of the palm oil industrial wastes as construction materials following the previous experimental research work.

Keywords: construction materials, oil palm shells (OPS), palm oil fuel ash (POFA), aggregates

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Authors: M. Mirmohammadi, S. Taghdisi, F. Anali

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Gossypol is a yellow anti-nutritional compound found in the cotton plant. This substance exists in the cottonseed and other parts of the cotton plant, such as bark, leaves, and stems. Chemically, gossypol is a very active polyphenolic aldehyde compound, and due to this polyphenolic structure, it has antioxidant and therapeutic properties. On the other hand, this compound, especially in free form, has many toxic effects, that its excessive consumption can be very dangerous for humans and animals. In this study, gossypol was extracted as a derivative compound of gossypol acetic acid from cottonseed using the n-hexane solvent with an efficiency of 0.84 ± 0.04, which compared to the Gossypol extracted from cottonseed oil with the same method (cold press) showed a significant difference with its efficiency of 1.14 ± 0.06. Therefore, it can be suggested to use cottonseed oil to extract this valuable compound. In the other part of this research, cottonseed extracts and cotton bolls extracts were obtained by two methods of soaking and Soxhlet with hydroalcoholic solvent taken with a ratio of (25:75), then by using extracts and corn starch powder, four herbal medicine code was created and after receiving the code of ethics (IR.SSU.REC.1398.136) the therapeutic effect of each one on the Cutaneous leishmaniasis resistant to drugs (caused by the leishmaniasis parasite) was investigated in real patients and its results was compared with the common drug glucantime (local ampoule) (n = 36). Statistical studies showed that the use of herbal medicines prepared with cottonseed extract and cotton bolls extract has a significant positive effect on the treatment of the disease’s wounds (p-value > 0.05) compared to the control group (only ethanol). Also, by comparing the average diameter of the wounds after a two-month treatment period, no significant difference was found between the use of ointment containing extracts and local glucantime ampoules (p-value < 0.05). Bolls extract extracted with the Soxhlet method showed the best therapeutic effects, although there was no significant difference between them (p-value < 0.05). Therefore, there is acceptable reliability to recommend this medicine for the treatment of Cutaneous leishmaniasis resistant to drugs without the side effects of the chemical drug glucantime and the pain of injecting the ampoule.

Keywords: cottonseed oil, gossypol, cotton boll, cutaneous leishmaniasis

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Authors: Ganesh B. Shinde, Vijaya B. Musande

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Cotton crop identification based on the timely information has significant advantage to the different implications of food, economic and environment. Due to the significant advantages, the accurate detection of cotton crop regions using supervised learning procedure is challenging problem in remote sensing. Here, classifiers on the direct image are played a major role but the results are not much satisfactorily. In order to further improve the effectiveness, variety of vegetation indices are proposed in the literature. But, recently, the major challenge is to find the better vegetation indices for the cotton crop identification through the proposed methodology. Accordingly, fuzzy c-means clustering is combined with neural network algorithm, trained by Levenberg-Marquardt for cotton crop classification. To experiment the proposed method, five LISS-III satellite images was taken and the experimentation was done with six vegetation indices such as Simple Ratio, Normalized Difference Vegetation Index, Enhanced Vegetation Index, Green Atmospherically Resistant Vegetation Index, Wide-Dynamic Range Vegetation Index, Green Chlorophyll Index. Along with these indices, Green Leaf Area Index is also considered for investigation. From the research outcome, Green Atmospherically Resistant Vegetation Index outperformed with all other indices by reaching the average accuracy value of 95.21%.

Keywords: Fuzzy C-Means clustering (FCM), neural network, Levenberg-Marquardt (LM) algorithm, vegetation indices

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Authors: Devinder Sharma, Sanjay Sharma, Ajay Goyal, Ashish Kapoor

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The present research paper discussed the durability properties of high strength concrete (HSC) using Foundry Slag(FD) as partial substitute for fine aggregates (FA) and Alccofine (AF) in addition to portland pozzolana (PPC) cement. Specimens of Concrete M100 grade with water/binder ratio 0.239, with Foundry Slag (FD) varying from 0 to 50% and with optimum quantity of AF(15%) were casted and tested for durability properties such as Water absorption, water permeability, resistance to sulphate attack, alkali attack and nitrate attack of HSC at the age of 7, 14, 28, 56 and 90 days. Substitution of fine aggregates (FA) with up to 45% of foundry slag(FD) content and cement with 15% substitution and addition of alccofine showed an excellent resistance against durability properties at all ages but showed a decrease in these properties with 50% of FD contents. Loss of weight in concrete samples due to sulphate attack, alkali attack and nitrate attack of HSC at the age of 365 days was compared with loss in compressive strength. Correlation between loss in weight and loss in compressive strength in all the tests was found to be excellent.

Keywords: alccofine, alkali attack, foundry slag, high strength concrete, nitrate attack, water absorption, water permeability

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Authors: Katharigatta N. Venugopala, Melendhran Pillay, Bander E. Al-Dhubiab

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Tuberculosis (TB) infection is caused mainly by Mycobacterium tuberculosis (MTB) and it is one of the most threatening and wide spread infectious diseases in the world. Benzothiazole derivatives are found to have diverse chemical reactivity and broad spectrum of pharmacological activity. Some of the important pharmacological activities shown by the benzothiazole analogues are antitumor, anti-inflammatory, antimicrobial, anti-tubercular, anti-leishmanial, anticonvulsant and anti-HIV properties. Keeping all these facts in mind in the present investigation it was envisaged to synthesize a series of novel {2-(benzo[d]-thiazol-2-yl-methoxy)-substitutedaryl}-(substitutedaryl)-methanones (4a-f) and characterize by IR, NMR (1H and 13C), HRMS and single crystal x-ray studies. The title compounds are investigated for in vitro anti-tubercular activity against two TB strains such as H37Rv (ATCC 25177) and MDR-MTB (multi drug resistant MTB resistant to Isoniazid, Rifampicin and Ethambutol) by agar diffusion method. Among the synthesized compounds in the series, test compound {2-(benzo[d]thiazol-2-yl-methoxy)-5-fluorophenyl}-(4-chlorophenyl)-methanone (2c) was found to exhibit significant activity with MICs of 1 µg/mL and 2 µg/mL against H37Rv and MDR-MTB, respectively when compared to standard drugs. Single crystal x-ray studies was used to study intra and intermolecular interactions, including polymorphism behavior of the test compounds, but none of the compounds exhibited polymorphism behavior.

Keywords: benzothiazole analogues, characterization, crystallography, anti-TB activity

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Authors: Yu-Chen Chang, Yen-Ping Peng, Wei-Yu Chen, Ku-Fan Chen

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Contamination of soil and groundwater has become a serious and widespread environmental problem. In this study, sustained-release persulfate tablets were developed using persulfate powder and a modified cellulose binder for organic-contaminated groundwater remediation. Conventional cement-based persulfate-releasing materials were also synthesized for the comparison. The main objectives of this study were to: (1) evaluate the release rates of the remedial tablets; (2) obtain the optimal formulas of the tablets; and (3) evaluate the effects of the tablets on the subsurface environment. The results of batch experiments show that the optimal parameter for the preparation of the persulfate-releasing tablet was persulfate:cellulose = 1:1 (wt:wt) with a 5,000 kg F/cm2 of pressure application. The cellulose-based persulfate tablet was able to release 2,030 mg/L of persulfate per day for 10 days. Compared to cement-based persulfate-releasing materials, the persulfate release rates of the cellulose-based persulfate tablets were much more stable. Moreover, since the tablets are soluble in water, no waste will be produced in the subsurface. The results of column tests show that groundwater flow would shorten the release time of the tablets. This study successfully developed unique persulfate tablets based on green remediation perspective. The efficacy of the persulfate-releasing tablets on the removal of organic pollutants needs to be further evaluated. The persulfate tablets are expected to be applied for site remediation in the future.

Keywords: sustained-release persulfate tablet, modified cellulose, green remediation, groundwater

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Authors: Margita Čanigová, Jana Račková, Miroslav Kročko, Viera Ducková, Vladimíra Kňazovická

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The aim of the study was to test the milk samples in terms of enterococci presence and their counts. Tested samples were as follows: raw cow milk, raw cow milk stored at 10°C for 16 hours and milk pasteurised at 72°C for 15 seconds. The typical colonies were isolated randomly and identified by classical biochemical test - EN-COCCUS test (Lachema, CR) and by PCR. Isolated strains were tested in terms of antibiotic resistance by well diffusion method. Examined antibiotics were: vancomycin (30 μg/disc), gentamicin (120 μg/disc), erythromycin (15 μg/disc), teicoplanine (30 μg/disc), ampicillin (10 μg/disc) and tetracycline (30 μg/disc). Average value of enterococci counts in raw milk cistern samples (n=30) was 8.25 ± 1.37 ×103 CFU/cm3. Storage tank milk samples (n=30) showed an increase (P > 0.05) and average value was 9.16 ± 1.49 × 103 CFU/cm3. Occurrence of enterococci in pasteurized milk (n=30) was sporadic and their counts were mostly below 10 CFU/cm3. Overall, 96 enterococci strains were isolated. In samples of raw cow milk and stored raw cow milk, Enterococcus faecalis was a dominant species (58.1% and 71.7%, respectively), followed by E. faecium (16.3% and 0%, respectively). Enterococcus mundtii, E. casseliflavus, E. durans and E. gallinarum were isolated, too. Resistances to ampicillin, erythromycin, gentamicin, tetracycline and vancomycin were found in 7.29%, 3.13%, 4.00%, 13.54% and 10.42% of isolated enterococci strains, respectively. Resistance to teicoplanine was not found in any isolated strain. All Vancomycin-Resistant Enterococci (VRE) belonged to E. faecalis. Obtained results confirmed that raw milk is a potential risk of enterococci resistant to antibiotics transmission into the food chain.

Keywords: antibiotic resistance, enterococci, milk, biosystems engineering

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Authors: Recep Keşli, Hayriye Tokay, Cengiz Demir, İsmail Ceyhan

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Objective: In many countries, tuberculosis (TB) is still one of the most important diseases. Tuberculosis is among top 10 causes of death worldwide. The early diagnosis of active tuberculosis still depends on the presence of acid resistant bacilli (ARB) in stained smears. In this study, we aimed to investigate the diagnostic performances of Erlich Ziehl Neelsen (EZN), Kinyoun and two different fluorescent stains. Methods: The specimens were obtained from the patients who applied to Chest Diseases Departments of Ankara Atatürk Chest Diseases and Thoracic Surgery Training and Research Hospital, and Afyon Kocatepe University, ANS Research and Practice Hospital. The study was carried out in the Medical Microbiology Laboratory, School of Medicine, Afyon Kocatepe University. All the non-sterile specimens were homogenized and decontaminated according to the EUCAST instructions. Samples were inoculated onto the Löwenstein-Jensen agars (bio-Merieux Marcy l'Etoile, France) and then incubated at 37˚C, for 40 days. Four smears were prepared from each specimen. Slides were stained with commercial EZN (BD, Sparks, USA), Kinyoun (SALUBRIS Istanbul, Turkey), Auramine (SALUBRIS Istanbul, Turkey) and Rhodamine (SALUBRIS Istanbul, Turkey) kit. While EZN and Kinyoun stainings were examined by light microscope, Auramine and Rhodamine slides were examined by fluorescence microscopy. Results: A total of 158 respiratory system samples (sputum, broncho alveolar lavage fluid…etc) were enrolled into the study. A hundred and two of the samples that processed were found as culture positive. The sensitivity, specificity, positive predictive, and negative predictive values were detected as 100%, 67.5%, 73.5%, and 100% for EZN, 100%, 70.9%, 77.4%, and 100% for Kinyoun, 100%,77.8%, 84.3%, 100% for Auramine, and 100%, 80% , 86.3%, and 100% for Rhodamine respectively. Conclusions: According to our study auramine and rhodamine staining methods showed the best diagnostic performance among the four investigated staining methods. In conclusion, the fluorochrome staining method may be accepted as the most reliable, rapid and useful method for diagnosis of the mycobacterial infections truly.

Keywords: acid resistant bacilli (ARB), auramine, Ehrlich-Ziehl-Neelsen (EZN), Kinyoun, Rhodamine

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Authors: Zohra Benfodda, Valentin Duvauchelle, Chaimae Majdi, David Bénimélis, Catherine Dunyach-Remy, Patrick Meffre

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New antibiotics are necessary to treat microbial pathogens, especially ESKAPE pathogens that are becoming increasingly resistant to available treatment. Despite the medical need, the number of newly approved drugs continues to decline. The majority of antibiotics under clinical development are natural products or derivatives thereof. 43 juglone/naphthazarin derivatives were synthesized using Minisci-type direct C–H alkylation and evaluated for their antibacterial properties against various clinical and reference Gram-positive MSSA, clinical Gram-positive MRSA. Different compounds of the synthesized series showed promising activity against clinical and reference MSSA (MIC: 1–8 μg/ml) and good efficacy against clinical MRSA (MIC: 2–8 μg/ml) strains. The synergistic effects of active compounds were evaluated with reference antibiotics (vancomycin and cloxacillin), and it was found that the antibiotic combination with those active compounds efficiently enhanced the antimicrobial activity and consequently the MIC values of reference antibiotics were lowered up to 1/16th of the original MIC. These synthesized compounds did not present hemolytic activity on sheep red blood cells. In addition to the in silico prediction of ADME profile parameter which is promising and encouraging for further development.

Keywords: juglone, naphthazarin, antibacterial, clinical MRSA, synergistic studies, MIC determination

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Authors: Ajmal Khan Kassi, Humayun Javed, Tariq Mukhtar

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The research was conducted to screen out resistance and susceptibility of okra varieties against Helicoverpa armigera under field conditions 2016. In this experiment, the different management practices viz. release Trichogramma chilonis, hoeing, and weeding, clipping, and lufenuron were tested individually and with all possible combinations for the controlling of American bollworm at 3 diverse localities viz. University research farm Koont, National Agriculture Research Centre (NARC) and farmer field Taxila by using resistant variety Arka Anamika. All the treatment combinations regarding damage of shoot and fruit showed significant results. The minimum fruit infestation, i.e., 3.20% and 3.58% was recorded with combined treatment (i.e., T. chilonis + hoeing + weeding + lufenuron) in two different localities. The minimum shoot infestation, i.e., 7.18%, 7.08%, and 6.85% was also observed with (T. chilonis + hoeing + weeding + lufenuron) combined treatment at all three different localities. The above-combined treatment (T. chilonis + hoeing + weeding + lufenuron) also resulted in maximum yield at NARC and Taxila, i.e., 57.67 and 62.66 q/ha respectively. On the basis of combined treatment (i.e., T. chilonis + hoeing + weeding + lufenuron) in three different localities, Arka Anamika variety proved to be comparatively resistant against H. armigera. So this variety is recommended for the cultivation in Pothwar region to get maximum yield and minimum losses against H. armigera.

Keywords: okra, screening, combine treatment, Helicoverpa armigera

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Authors: Sinethemba Yakobi, Lindiwe Zuma, Ofentse Pooe

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Gonococcal infections present a notable public health issue, and the major approach for treatment involves using β-lactam antibiotics that specifically target penicillin-binding protein 2 (PBP2) in Neisseria gonorrhoeae. This study examines the influence of flavonoids, namely rutin, on the structural changes of PBP2 in both penicillin-resistant (FA6140) and penicillin-susceptible (FA19) strains. The research clarifies the structural effects of particular mutations, such as inserting an aspartate residue at position 345 (Asp-345a) in the PBP2 protein. The strain FA6140, which is resistant to penicillin, shows specific changes that lead to a decrease in penicillin binding. These mutations, namely P551S and F504L, significantly impact the pace at which acylation occurs and the stability of the strain under high temperatures. Molecular docking analyses investigate the antibacterial activities of rutin and other phytocompounds, emphasizing its exceptional binding affinity and potential as an inhibitor of PBP2. Quercetin and protocatechuic acid have encouraging antibacterial effectiveness, with quercetin displaying characteristics similar to those of drugs. Molecular dynamics simulations offer a detailed comprehension of the interactions between flavonoids and PBP2, highlighting rutin's exceptional antioxidant effects and strong affinity for the substrate binding site. The study's wider ramifications pertain to the pressing requirement for antiviral treatments in the context of the ongoing COVID-19 epidemic. Flavonoids have a strong affinity for binding to PBP2, indicating their potential as inhibitors to impair cell wall formation in N. gonorrhoeae. Ultimately, this study provides extensive knowledge on the interactions between proteins and ligands, the dynamics of the structure, and the ability of flavonoids to combat penicillin-resistant N. gonorrhoeae bacteria. The verified simulation outcomes establish a basis for creating potent inhibitors and medicinal therapies to combat infectious illnesses.

Keywords: phytochemicals, penicillin-binding protein 2, gonococcal infection, ligand-protein interaction, binding energy, neisseria gonorrhoeae FA19, neisseria gonorrhoeae FA6140, flavonoids

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Authors: M. Eckert, M. Oliveira, A. Bettencourt Ribeiro

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The intensive use of natural aggregate, near the towns, associated to the increase of the global population, leads to its depletion and increases the transport distances. The uncontrolled deposition of construction and demolition waste in landfills and city outskirts, causes pollution and take up space for noblest purposes. The main problem of recycled aggregate lies in its high water absorption, what is due to the porosity of the materials which constitute this type of aggregate. When the aggregates are dry, water flows from the inside to the engaging cement paste matrix, and when they are saturated an inverse process occurs. This water flow breaks the aggregate-cement paste bonds and the greater water concentration, in the inter-facial transition zone, degrades the concrete properties in its fresh and hardened state. Based on the water absorption over time, it was optimized an staged mixing method, to regulate the said flow and manufacture recycled aggregate concrete with levels of work-ability, strength and shrinkage equivalent to those of conventional concrete.The physical, mechanical and geometrical properties of the aggregates where related to the properties of concrete in its fresh and hardened state. Three types of commercial recycled aggregates and two types of natural aggregates where evaluated. Six compositions with different percentages of recycled coarse aggregate where tested.

Keywords: recycled aggregate, water absorption, interfacial transition zone, compressive-strength, shrinkage

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Authors: R. Malathy

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High performance concrete is not only characterized by its high strength, workability, and durability but also by its smartness in performance without human care since the first day. If the concrete can cure on its own without external curing without compromising its strength and durability, then it is said to be high performance self-curing concrete. In this paper, an attempt is made on the performance study of internally cured concrete using biomaterials, namely Spinacea pleracea and Calatropis gigantea as self-curing agents, and it is compared with the performance of concrete with existing self-cure chemical, namely polyethylene glycol. The present paper focuses on workability, strength, and durability study on M20, M30, and M40 grade concretes replacing 30% of fly ash for cement. The optimum dosage of Spinacea pleracea, Calatropis gigantea, and polyethylene glycol was taken as 0.6%, 0.24%, and 0.3% by weight of cement from the earlier research studies. From the slump tests performed, it was found that there is a minimum variation between conventional concrete and self-cured concrete. The strength activity index is determined by keeping compressive strength of conventionally cured concrete for 28 days as unity and observed that, for self-cured concrete, it is more than 1 after 28 days and more than 1.15 after 56 days because of secondary reaction of fly ash. The performance study of concretes in aggressive environment like acid attack, sea water attack, and chloride attack was made, and the results are positive and encouraging in bio-self-cured concretes which are ecofriendly, cost effective, and high performance materials.

Keywords: bio materials, Calatropis gigantea, self curing concrete, Spinacea oleracea

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Authors: Fatima Ghebghoub

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The solvent extraction of cobalt (II) from sulfate medium using di(2-ethylhexy1) phosphoric acid (D2EHPA, HL) at 25°C has been investigated. The influence of the following parameters was studied: the equilibrium pH, the concentration of the extractant and the nature of diluent. The effect of the diluent using polar and non-polar solvents in the extraction of nickel(II) is discussed. The extracted nickel (II species were found to be CoL2 in 1-octanol and methyl isobutyl ketone and CoL2.2HL in toluene, dichloromethane, chloroform, carbon tetrachloride and cyclohexane. The extraction constants are evaluated for the different diluents.

Keywords: liquid-liquid extraction, cobalt(II), di(2-ethylhexyl) phosphoric acid, diluent effect

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Authors: Alsulami H., Alghamdi N., Alasker A., Almohen N., Shome D.

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Most conventional chemotherapeutic agents which are used for the treatment of cancers not only eradicate cancer cells but also affect normal hematopoietic Stem cells (HSCs) that leads to severe pancytopenia during treatment. Therefore, a need exists for novel approaches to treat cancer without or with minimum effect on normal HSCs. Parthenolide (PTL), a herbal product occurring naturally in the plant Feverfew, is a potential new chemotherapeutic agent for the treatment of many cancers such as acute myeloid leukemia (AML) and chronic lymphocytic leukemia (CLL). In this study we investigated the effect of different PTL concentrations on the viability of normal HSCs and also on the ability of these cells to form colonies after they have been treated with PTL in vitro. Methods: In this study, 24 samples of bone marrow and cord blood were collected with consent, and mononuclear cells were separated using density gradient separation. These cells were then exposed to various concentrations of PTL for 24 hours. Cell viability after culture was determined using 7ADD in a flow cytometry test. Additionally, the impact of PTL on hematopoietic stem cells (HSCs) was evaluated using a colony forming unit assay (CFU). Furthermore, the levels of NFҝB expression were assessed by using a PE-labelled anti-pNFκBP65 antibody. Results: this study showed that there was no statistically significant difference in the percentage of cell death between untreated and PTL treated cells with 5 μM PTL (p = 0.7), 10 μM PTL (p = 0.4) and 25 μM (p = 0.09) respectively. However, at higher doses, PTL caused significant increase in the percentage of cell death. These results were significant when compared to untreated control (p < 0.001). The response of cord blood cells (n=4) on the other hand was slightly different from that for bone marrow cells in that the percentage of cell death was significant at 100 μM PTL. Therefore, cord blood cells seemed more resistant than bone marrow cells. Discussion &Conclusion: At concentrations ≤25 μM PTL has a minimum or no effect on HSCs in vitro. Cord blood HSCs are more resistant to PTL compared to bone marrow HSCs. This could be due to the higher percentage of T-lymphocytes, which are resistant to PTL, in CB samples (85% in CB vs. 56% in BM. Additionally, CB samples contained a higher proportion of CD34+ cells, with 14.5% of brightly CD34+ cells compared to only 1% in normal BM. These bright CD34+ cells in CB were mostly negative for early-stage stem cell maturation antigens, making them young and resilient to oxidative stress and high concentrations of PTL.

Keywords: stem cell, parthenolide, NFKB, CLL

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Authors: Ahmed Al-Mansour, Qiang Zeng

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Recycling waste plastics in the form of concrete components, i.e. fine aggregates, has been an attractive topic among the society of civil engineers. Not only does the recycling of plastics reduce the overall cost of concrete production, but it also takes part in solving environmental issues. Nevertheless, the incorporation of recycled plastics into concrete results in an increasing reduction in the mechanical properties of concrete as the percentage of replacement of natural aggregates increases. In order to overcome this reduction, Ethylene-vinyl acetate (EVA) was used as an additive in concrete with recycled plastic aggregates. The aim of this additive is to: 1) increase the interfacial interaction at the interfacial transition zone (ITZ) between plastic pellets and cement matrix, and 2) mitigate the loss in mechanical properties. Three different groups of samples (i.e. cubes and prisms) were tested according to the plastics substituting fine aggregates. 5, 10, and 15% of fine aggregates were substituted for recycled plastic pellets, and 2 – 4% of the cement was substituted for EVA that produces a flexible agent when mixed properly with water. Compressive and tensile strength tests were conducted for the mechanical properties, while SEM and X-CT scan were implemented for further investigation of calcium-silicate-hydrate (C–S–H) formation and ITZ analysis. The optimal amount of plastic particles with EVA is suggested to get the most compact and dense matrix structure according to the results of this study.

Keywords: the durability of concrete, ethylene-vinyl acetate (EVA), interfacial transition zone (ITZ), recycled plastics

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Authors: Kanchan Maji, Debasmita Pani, Sudip Dasgupta

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Calcium phosphate cement (CPC) due to its high bioactivity and optimum bioresorbability shows excellent bone regeneration capability. Despite it has limited applications as bone implant due to its macro-porous microstructure causing its poor mechanical strength. The reinforcement of apatitic CPCs with biocompatible fibre glass phase is an attractive area of research to improve its mechanical strength. Here we study the setting behaviour of Si-doped and un-doped alpha tri-calcium phosphate (α-TCP) based CPC and its reinforcement with the addition of E-glass fibre. Alpha tri-calcium phosphate powders were prepared by solid state sintering of CaCO3, CaHPO4 and tetra ethyl ortho silicate (TEOS) was used as silicon source to synthesise Si doped α-TCP powders. Alpha tri-calcium phosphate based CPC hydrolyzes to form hydroxyapatite (HA) crystals having excellent osteoconductivity and bone-replacement capability thus self-hardens through the entanglement of HA crystals. Setting time, phase composition, hydrolysis conversion rate, microstructure, and diametral tensile strength (DTS) of un-doped CPC and Si-doped CPC were studied and compared. Both initial and final setting time of the developed cement was delayed because of Si addition. Crystalline phases of HA (JCPDS 9-432), α-TCP (JCPDS 29-359) and β-TCP (JCPDS 9-169) were detected in the X-ray diffraction (XRD) pattern after immersion of CPC in simulated body fluid (SBF) for 0 hours to 10 days. The intensities of the α-TCP peaks of (201) and (161) at 2θ of 22.2°and 24.1° decreased when the time of immersion of CPC in SBF increased from 0 hours to 10 days, due to its transformation into HA. As Si incorporation in the crystal lattice stabilised the TCP phase, Si doped CPC showed a little slower rate of conversion into HA phase as compared to un-doped CPC. The SEM image of the microstructure of hardened CPC showed lower grain size of HA in un-doped CPC because of premature setting and faster hydrolysis of un-doped CPC in SBF as compared that in Si-doped CPC. Premature setting caused generation of micro and macro porosity in un-doped CPC structure which resulted in its lower mechanical strength as compared to that in Si-doped CPC. This lower porosity and greater compactness in the microstructure attributes to greater DTS values observed in Si-doped CPC. E-glass fibres of the average diameter of 12 μm were cut into approximately 1 mm in length and immersed in SBF to deposit carbonated apatite on its surface. This was performed to promote HA crystal growth and entanglement along the fibre surface to promote stronger interface between dispersed E-glass fibre and CPC matrix. It was found that addition of 10 wt% of E-glass fibre into Si-doped α-TCP increased the average DTS of CPC from 8 MPa to 15 MPa as the fibres could resist the propagation of crack by deflecting the crack tip. Our study shows that biocompatible E-glass fibre in optimum proportion in CPC matrix can enhance the mechanical strength of CPC without affecting its bioactivity.

Keywords: Calcium phosphate cement, biocompatibility, e-glass fibre, diametral tensile strength

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Authors: A. O. David, A. A. Akaho, M. A. Abah, J. O. Ogunjimi

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This study focuses on the growing concerns about the quality of groundwater found around cement factories, which have caused several health issues for residents located within two (2) kilometer radius. The qualities of groundwater were determined by an investigative study that involved the determination of some heavy metals and physicochemical properties in drinking water samples. Eight (8) samples of groundwater were collected from the eight sampling sites. The samples were analysed for the following parameters; iron, copper, manganese, zinc, lead, color, dissolved solids, electrical conductivity, pH, dissolved oxygen (DO), biological oxygen demand (BOD), chemical oxygen demand (COD), temperature, turbidity and total hardness using standard methods. The test results showed the variation of the investigated parameters in the samples as follows: temperature 26-31oC, pH 5.9-7.2, electrical conductivity (EC) 0.37 – 0.78 µS/cm, total hardness 181.8 – 333.0 mg/l, turbidity 0.00-0.05 FTU, colour 5-10 TCU, dissolved oxygen 4.31-5.01 mg/l, BOD 0.2-1.0 mg/l, COD 2.0 -4.0 mg/l, Cu 0.04 – 0.09 mg/l, Fe 0.006-0.122 mg/l, Zn 0.016-0.306 mg/l, Mn 0.01-0.05 mg/l and Pb < 0.001 mg/l. The World Health Organization's standard for drinking water quality guidelines was exceeded in several of the analyzed parameters' amounts in the drinking water samples from the study area. The dissolved oxygen was found to exceed 5.0 mg/l, which is the WHO permissible limit; also, Limestone was found to exceed the WHO maximum limit of 170 mg/l. All the above results confirmed the high pollution of the groundwater sources, and hence, they are not suitable for consumption without any prior treatment.

Keywords: groundwater, quality, heavy metals, parameters

Procedia PDF Downloads 68