61 research outputs found

    Effects of Plastering and Ferrocement on the Shear Properties of Masonry Triplets

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    Masonry triplet is formed by three and half bricks keeping the same type of bond exhibited in a brick wall.  The triplet has been investigated by researchers as an indicator of lateral loading capacity of masonry wall.  Although strength is an important parameter in determining the property of triplet, displacement capacity is significant specially for the cases of lateral loads such as wind load or earthquake load.  Experimental investigations carried out to determine the effect of plastering and ferrocement in masonry triplets in terms of both shear strength and strain at maximum stress.  The study identified several parameters that affect these properties e.g. mortar strength, mortar thickness, compressive strength of brick, plastering layer thickness, diameter of the wire mesh, and amount of wire mesh.  Equations have been proposed to determine the shear strength and strain at maximum stress of the triplet based on these factors.  Bond strength was found to be the key factor for the failure of the triplets.  It can be inferred that the construction in Bangladesh lack the bond strength in the horizontal bed surface, decreasing both the load and displacement capacity of the brick wall.  Ferrocement can be used as a retrofitting technique as it has been found from the tests that laminating the triplet surface with ferrocement prevents sudden collapse and confines the triplet so that the shear strength and strain at maximum stress increase.

    Evaluation of Three Chitin Metal Silicate Co-Precipitates as a Potential Multifunctional Single Excipient in Tablet Formulations

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    The performance of the novel chitin metal silicate (CMS) co-precipitates as a single multifunctional excipient in tablet formulation using direct compression and wet granulation methods is evaluated. The neutral, acidic, and basic drugs Spironolactone (SPL), ibuprofen (IBU) and metronidazole (MET), respectively, were used as model drugs. Commercial Aldactone®, Fleximex® and Dumazole® tablets containing SPL, IBU and MET, respectively, and tablets made using Avicel® 200, were used in the study for comparison purposes. Tablets of acceptable crushing strength (>40 N) were obtained using CMS. The friability values for all tablets were well below the maximum 1% USP tolerance limit. CMS produced superdisintegrating tablets (disintegration time < 1 min) with the three model drugs. Regarding the dissolution rate, the sequence was as follow: CMS > Fleximex® > Avicel® 200, CMS > Avicel® 200 > Dumazole® and Aldactone® > Avicel® 200 > CMS for IBU, MET and SPL, respectively. Compressional properties of formulations were analyzed using density measurements and the compression Kawakita equation as assessment parameters. On the basis of DSC results, CMS co precipitates were found to be compatible with the tested drugs. Conclusively, the CMS co-precipitates have the potential to be used as filler, binder, and superdisintegrant, all-in-one, in the design of tablets by the direct compression as well as wet granulation methods

    Development and evaluation of a novel, multifunctional, coprocessed excipient via roller compaction of α-Lactose Monohydrate and Magnesium Silicate

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    This study investigates co-processing lactose with synthetic amorphous magnesium silicate with the aim of expanding the use of directly compressible excipients based on native lactose. The co-processing was performed using roller compaction. The co-processed excipient was characterized using particle size analysis and compression properties (Kawakita equation). The co-processed excipient demonstrated plastic behavior upon compression, good flowability and crushing strength and a shorter disintegration time. Compatibility between the different ingredients of the co-processed excipient, as well as, between the co-processed excipient and model drugs was tested using Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared spectroscopy (FTIR). The interaction between lactose and magnesium silicate proved to be of a physical nature. Formulating this co-processed excipient with Mebeverine HCl and Losartan Potassium as model drugs, indicated its suitability as a single multi-functional excipient. Co-processed lactose with magnesium silicate could be used as a single direct compression excipient for tablet manufacturing

    A bio-sustainable approach for reducing Eucalyptus tree-caused agricultural ecosystem hazards employing Trichoderma bio-sustained spores and mycorrhizal networks

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    The presence of the exotic Eucalyptus tree in crop-growing soil and the accumulation of its undecomposed leaves is a significant ecological hazard. The waxy coating on the leaves and the phenolic compounds takes a long time to break down under normal conditions. It is necessary to explore various fungi that can degrade these leaves for an eco-friendly solution to this problem. In this study, spores of nine native Trichoderma strains were produced on wheat agar using a lactic acid-induced sporulation strategy (LAISS). Trichoderma biosustained spores and Serendipita indica (SI) spores were applied to a rice field with accumulated Eucalyptus leaves under continuous ponding (CP) and alternate flooding and wetting conditions (AFW). Among the strains, TI04 (Trichoderma viride) and TI15 (Trichoderma citrinoviride) showed faster (5 days) and massive sporulation (1.06–1.38 × 1011 CFU/g) in LAISS. In vitro, TI04 and TI15 biosustained on Eucalyptus leaves and improved rice seedling growth and SI infection under greenhouse conditions. In the rice-field experiment, Trichoderma-treatment had a threefold yield (percentage) increase from control, with TI04 (CP) increasing the yield by 30.79, TI04 (AFW) by 29.45, TI15 (CP) by 32.72, and TI15 (AFW) rising by 31.91. Remarkably, unfilled grain yield significantly decreased in all the Trichoderma treatments. Under AFW conditions, TI04 and TI15 showed a higher pH increase. Furthermore, TI04 and TI15 under AFW had higher water productivity (t ha−1 cm−1) of 0.0763 and 0.0791, respectively, and the highest rates (percentage) of SI colonization of 86.36 and 83.16, respectively. According to the findings, LAISS-produced Trichoderma spores can be applied to break down persistent wastes and restore agricultural ecosystems through increased mycorrhizae networking

    Pyrazole derivatives of pyridine and naphthyridine as proapoptotic agents in cervical and breast cancer cells

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    Cancer is one of the leading causes of death worldwide. The increasing prevalence and resistance to chemotherapy is responsible for driving the search of novel molecules to combat this disease. In search of novel compounds with pro-apoptotic potential, pyrazolo-pyridine and pyrazolo-naphthyridine derivatives were investigated against cervical cancer (HeLa) and breast cancer (MCF-7) cells. The anti-proliferative activity was determined through the MTT assay. Potent compounds were then analyzed for their cytotoxic and apoptotic activity through a lactate dehydrogenase assay and fluorescence microscopy after propidium iodide and DAPI staining. Flow cytometry was used to determine cell cycle arrest in treated cells and pro-apoptotic effect was verified through measurement of mitochondrial membrane potential and activation of caspases. Compounds 5j and 5k were found to be most active against HeLa and MCF-7 cells, respectively. G0/G1 cell cycle arrest was observed in treated cancer cells. Morphological features of apoptosis were also confirmed, and an increased oxidative stress indicated the involvement of reactive oxygen species in apoptosis. The compound-DNA interaction studies demonstrated an intercalative mode of binding and the comet assay confirmed the DNA damaging effects. Finally, potent compounds demonstrated a decrease in mitochondrial membrane potential and increased levels of activated caspase-9 and -3/7 confirmed the induction of apoptosis in treated HeLa and MCF-7 cells. The present work concludes that the active compounds 5j and 5k may be used as lead candidates for the development of lead drug molecules against cervical and breast cancer

    Efficient Congestion Minimisation by Successive Load Shifting in Multilayer Wireless Networks

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    Congestion in wireless networks is one of the major causes of system inefficiency, and with router load being the main contributor to overall network traffic flow, congestion is very dependent on the level of router load and how it can be effectively managed. This paper presents a novel low-complexity Successive Load Shifting (SLS) technique for intelligently shifting router load between network routers by predicting the probability of congestion occurrences in the network and exploiting the topology to reassign load to minimise congestion. Crucially, SLS does not compromise the data rate in avoiding congestion and is able to be seamlessly embedded into existing protocols with only a small increase incurred in system overheads. The performance of SLS has been extensively tested and critically evaluated using the widely adopted TCP and UDP protocols, with results confirming both significant throughput gains and superior packet loss performance

    Early loss of Crebbp confers malignant stem cell properties on lymphoid progenitors.

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    Loss-of-function mutations of cyclic-AMP response element binding protein, binding protein (CREBBP) are prevalent in lymphoid malignancies. However, the tumour suppressor functions of CREBBP remain unclear. We demonstrate that loss of Crebbp in murine haematopoietic stem and progenitor cells (HSPCs) leads to increased development of B-cell lymphomas. This is preceded by accumulation of hyperproliferative lymphoid progenitors with a defective DNA damage response (DDR) due to a failure to acetylate p53. We identify a premalignant lymphoma stem cell population with decreased H3K27ac, which undergoes transcriptional and genetic evolution due to the altered DDR, resulting in lymphomagenesis. Importantly, when Crebbp is lost later in lymphopoiesis, cellular abnormalities are lost and tumour generation is attenuated. We also document that CREBBP mutations may occur in HSPCs from patients with CREBBP-mutated lymphoma. These data suggest that earlier loss of Crebbp is advantageous for lymphoid transformation and inform the cellular origins and subsequent evolution of lymphoid malignancies

    Evolving trends in the management of acute appendicitis during COVID-19 waves. The ACIE appy II study

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    Background: In 2020, ACIE Appy study showed that COVID-19 pandemic heavily affected the management of patients with acute appendicitis (AA) worldwide, with an increased rate of non-operative management (NOM) strategies and a trend toward open surgery due to concern of virus transmission by laparoscopy and controversial recommendations on this issue. The aim of this study was to survey again the same group of surgeons to assess if any difference in management attitudes of AA had occurred in the later stages of the outbreak. Methods: From August 15 to September 30, 2021, an online questionnaire was sent to all 709 participants of the ACIE Appy study. The questionnaire included questions on personal protective equipment (PPE), local policies and screening for SARS-CoV-2 infection, NOM, surgical approach and disease presentations in 2021. The results were compared with the results from the previous study. Results: A total of 476 answers were collected (response rate 67.1%). Screening policies were significatively improved with most patients screened regardless of symptoms (89.5% vs. 37.4%) with PCR and antigenic test as the preferred test (74.1% vs. 26.3%). More patients tested positive before surgery and commercial systems were the preferred ones to filter smoke plumes during laparoscopy. Laparoscopic appendicectomy was the first option in the treatment of AA, with a declined use of NOM. Conclusion: Management of AA has improved in the last waves of pandemic. Increased evidence regarding SARS-COV-2 infection along with a timely healthcare systems response has been translated into tailored attitudes and a better care for patients with AA worldwide
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