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Comparative study on shear strength and life cycle assessment of reinforced concrete beams containing different types of fibers
Get PDFA variety of fibers currently exists in the construction market; however, their effect on concrete performance, cost, and environment are not being evaluated systematically. This study investigates the influence of different fibers (polypropylene, glass, basalt, polyvinyl alcohol, and steel), having different aspect ratios, on shear strength of reinforced concrete beams designed without stirrups. A life cycle assessment for each fiber type highlighting the environmental emissions and production costs is performed. Test results showed that the shear strength increased by 38.6% with the use of polypropylene fibers possessing low aspect ratio of 42, while such increase was limited to 11.5% with the incorporation of basalt fibers possessing an aspect ratio of 700. The polyvinyl alcohol fibers exhibited the highest ductility and energy transfer in the post-peak region, while the load versus deflection curves sharply dropped for concrete containing steel fibers reflecting reduced adhesion with the cement paste. The life cycle assessment showed higher environmental impact varying from 4% to 9% due to fibers additions, together with increased cost ranging between 34% and 150%. When taking all factors into account (performance, cost, and environmental impact), the polyvinyl alcohol fibers were most efficient followed by the polypropylene ones. © 2023 The Author
The Effect of Chronic Cigarette Smoking on the Kidneys in Male Mice and In Ovariectomized and Non-Ovariectomized Female Mice
No full textChronic Cigarette Smoking (CS), a well-known risk factor for numerous diseases, has been shown to play a significant influence in renal disorders in both females and males. The progression of chronic kidney disease (CKD) may change depending on gender. According to national US reports, men died from CKD at a higher rate than women in most states. In accordance, premenopausal women are less prone to CKD due to the presence of estrogen. Estrogen is known to be nephroprotective and exerts its effect on several aspects. The objective of this study is to examine the effects of CS on the kidneys and to assess the involvement of estrogen in that regard. Age-matched C57BL/6J female and male mice were divided into 5 groups: 1) Male control group; 2) Male CS group; 3) Female control group; 4) Female CS group, and 5) Ovariectomized female CS group. Cardiac systolic function was evaluated, and kidneys were subjected to histological and molecular analysis. Hemodynamic cardiac assessment revealed an enhanced heart workload characterized by a marked elevation in blood pressure and cardiac output in ovariectomized female group. Our renal findings indicate that females are more prone to morphological alterations and fibrosis following CS as evidenced by a significant increase in bowman’s capsule area, a remarkable retraction in the glomerular capillary area, and a remarkable decrease in the proximal tubule area in both CS females and CS ovariectomized groups. On the other hand, these parameters weren’t affected following CS in males. Moreover, CS female and CS ovariectomized female groups exhibited a significant increase in renal fibrosis paralleled with a decrease in renal mRNA expression of MMP-2 and MMP-9 levels. These expressions were reversed in CS male group. In addition, there was a significant decrease in α-smooth muscle actin (α-SMA) protein level, a renal pro-fibrotic marker, in males. However, renal inflammatory assessment showed that CS males are more prone to inflammation with a marked decrease in the anti-inflammatory IL-4 protein levels and a substantial rise in the pro-inflammatory TNF-α mRNA expression levels. In Conclusion, following 8 weeks of CS, the female kidneys seem to experience prominent morphological alterations while males seem to have an imbalanced inflammatory profile. Although the ovariectomized CS females were hemodynamically affected two days post-CS cessation, at the level of the kidneys, the estrogen effect seems to be masked in the presence of CS as such results were more likely consistent with the ovariectomized CS female
Impact of diagenesis and pore aspects on the petrophysical and elastic properties of carbonate rocks from southern Lebanon
Get PDFCarbonate rocks form under widely variable depositional settings and are susceptible to complicated diagenetic processes which influence their petrophysical and elastic properties. Understanding the controlling factors on these rock parameters is crucial for the interpretation of sonic logs and seismic reflection profiles. Herein, we collect a large number of carbonate rock samples exposed at southern Lebanon to examine the lithofacies, pore types, diagenetic processes, and their impact on the petrophysical and elastic properties. Collected samples belong to the Upper Cretaceous, Eocene, and Miocene limestone beds and are dominated by bioclastic packstone/wackestone from carbonate shelf deposits which are more susceptible to early diagenesis. Measured porosity is generally moderate to high and varies between 10 and 40%, with a pore system dominated by intraparticle, moldic, and vuggy pores. A small amount of porosity is represented by fractures and interparticle pores. Permeability is very low due to the dominance of isolated intraparticle porosity and small micropores. The measured density and the seismic wave velocities are low due to the moderate/high porosity and the presence of a significant (~ 17%) non-carbonate matrix. Many diagenetic features, such as micritization, cementation, compaction, and dissolution, impacted porosity and permeability differently (dependent on the pore throat size) and led also to the widely variable but generally low seismic wave velocities. The wide scatter observed in the porosity-velocity data cannot be explained solely by the microfacies, pore types, or mineralogy. Instead, we used effective medium theories to explain the variability of seismic velocities with porosity and the petrographic characteristics of the studied rocks. Modeling results show that, in addition to porosity, composition, rock texture, pore types, and the pore aspect ratios have significant impacts on the elastic properties of the studied samples which could explain the observed variations of seismic wave velocities at a given porosity. These findings are crucial for a better characterization of both onshore and offshore carbonate rocks which may host hydrocarbon, groundwater, and geothermal energy resources. © 2023, Springer-Verlag GmbH Germany, part of Springer Nature
NOVEL APPROACH FOR EX-VIVO EXPANSION OF HEMATOPOIETIC STEM CELLS USING DECELLULARIZED HUMAN UMBILICAL CORD EXTRACTS
No full textHematopoietic stem cell transplantations (HSCT) represent so far, the only efficient reconstructive tool for damaged bone marrow (BM) in hematological disorders. The success of these regenerative strategies relies on the hematopoietic stem cells’ (HSC) availability, quality, stemness, and potency. Many constraints can hinder these therapies whether through the limited success in the ex-vivo expansion of HSCs, their different sources, or their substandard engraftment outcomes, which ultimately restrain HSCs from reaching their utmost clinical therapeutic potential. The central hub of adult HSCs, the BM niche, compartmentalizes supporting cells, the extracellular matrix (ECM), and soluble factors which collectively dictate the fate of HSCs. For this reason, recent investigations have relied on the application of umbilical cord-derived ECM (UC-ECM) as an alternative source to expand HSCs, owing to their similarities with BM-ECM in their biochemical composition, their ease of accessibility as biological leftovers, and their ability to surpass ethical concerns. Hence, our study is focused on establishing a multifaceted culture system comprised of mobilized peripheral blood-derived HSCs, seeded on BM-derived MSCs (BM-MSC) supporting monolayer, both of which are supported by decellularized UC-derived ECM. Therefore, by remaining faithful to the native HSC milieu, we have successfully established a BM mimetic culture system that supports the survival and maintenance of CD34+ HSCs. We have found that UC-ECM-treated BM-MSC monolayers create an in-vivo mimicry microenvironment that aids in preserving CD34+ HSC stemness. Thus, our culture system employs low-cost, easily accessible, biocompatible, and biochemically active scaffold material capable of competing with the modern, highly complex, and expensive expansion strategies that can ultimately serve the uprise of regenerative therapies for BM regeneration
Glyphosate Alters Mammary Lobular and Ductal Epithelial Cell Differentiation and Triggers Tumor Initiation Events
Get PDFCancer remains a threat for patients around the world, with an estimated 19.3 million peo-ple diagnosed in 2020. Specifically, breast cancer has been recently found to be the most prominently diagnosed cancer globally, accounting for 15.5% of deaths related to cancer in females. The cellular change toward oncogenesis is closely linked to environmental fac-tors such as herbicides, tobacco, and alcohol.
Glyphosate is the most widely used herbicide globally, with usage increasing over the years, from 16 million kg spread in the world in 1994 to 79 million kg spread in 2014, including 15% in the United States alone. The International Agency for Research on Can-cer (IARC) classified glyphosate as "probably carcinogenic to humans" (Group 2A) in March 2015, based on "limited" evidence of cancer in humans and "sufficient" evidence of cancer in experimental animals.
Although some studies have looked into its effect on the progression of cancer in tumor-igenic cells, it is still unknown whether glyphosate may initiate cancer and disrupt differ-entiation in normal cells. In this study, we opted to investigate the impact of glyphosate in initiating tumor-like phenotypes in non-tumorigenic estrogen-positive lobular mouse (SCp2) and ductular human estrogen-negative (HMT-3522 S1) breast epithelial cells and disrupting differentiation markers. Our results show that long-term glyphosate exposure did not affect growth rate, but enhanced the invasion compared to the untreated control (~8-fold increase upon 10-11 M glyphosate; p <0.05), matrix metalloproteinase-9 (MMP-9) release, and triggered a 4-fold miR-183 upregulation (preliminary), the most overex-pressed miRNA in early-stage Lebanese breast cancer patients, in SCp2 cells. Long-term as well as short-term glyphosate treatments of human derived S1 cells exhibited an en-hanced cell invasion across a reconstituted basement membrane, whereas long-term expo-sure disrupted lumen formation in their 3D cultures, compared to non-treated cells (~1.3-fold and 1.2-fold increase upon 10-5 and 10-11 M glyphosate, respectively; p <0.05). Short and long-term treatments with glyphosate disrupted the distribution of cell polarity marker β-catenin from and apical to a basolateral distribution. Moreover, we showed the effect of the herbicide on the differentiation markers of SCp2 and S1 cells by evaluating levels of β-casein expression and assessing the effect of treatment on lumen formation, respectively. β-casein expression significantly decreased upon 10-11 M glyphosate treat-ment (p <0.05). We additionally propose a possible pathway for the effect of glyphosate on the activation of breast cancer-related signaling pathways using Ingenuity Pathway Analysis (IPA) in estrogen-dependent cells.
In conclusion, our findings may provide insight on the function of glyphosate in tumor initiation events, suggesting that such chemicals might "injure" nontumorigenic breast epi-thelial cells. Further research may be necessary to fully understand the extent of these ef-fects and to develop alternative methods for weed control that do not rely on glyphosate
A flurry of feminist knowledge production in the SWANA region and the emergence of a robust young intersectional movement
Get PDFConception of efficient key-dependent binary diffusion matrix structures for dynamic cryptographic algorithms
No full textThe existing static cryptographic algorithms suffer from different performance and security challenges. These limitations are attributed to their fixed structure, where the substitution and diffusion primitives maintain the same values throughout the process. In this paper, we present a new framework of a dynamic binary diffusion matrix with flexible dimensions (n×n). The proposed solution replaces the static diffusion primitives, in existing symmetric and un-keyed cryptographic algorithms, with dynamic primitives. We define six different dynamic and flexible binary diffusion forms, four that are invertible, and two that are non-invertible, and hence, they could be used for different security services. However, using a single diffusion form does not always guarantee the required cryptographic properties. To that effect, we propose a binary multiplication scheme of a dynamic primary matrix and its transposed form, which yields the desired efficiency, and provides good resistance against recent implementation attacks, yet without degrading the system performance. We conduct security and performance analyses to validate the effectiveness of the proposed solution. The results confirm the cryptographic performance in terms of the linear branch number and the number of fixed points. In this context, the best-obtained branch number is 4 for n=8 and 5 for n=12 for the invertible forms, while for the non-invertible ones, the best branch number is 3 for n=8 and 4 for n=12. Moreover, in terms of the number of fixed points, the obtained numbers are very close to 0 for the invertible and non-invertible forms. © 2023 Elsevier Lt
Utilizing NGS in AMR Surveillance in North Lebanon - A One Health Approach
Get PDFBackground: The global rates of antimicrobial resistance (AMR) are rising at an alarming rate with dreadful circumstances of more than 10 million deaths per year by 2050. In the Eastern Mediterranean Region (EMR), reported rates of resistance have reached dangerous levels both in healthcare settings and the community, threatening the hard-won gains in health and development, and the sustainability of public health response to many communicable diseases. AMR surveillance systems are the core component of infectious disease management and the foundation for a better understanding of the spread of antimicrobial resistance. In Lebanon, data on AMR surveillance is fragmented and lack representativeness. To this, we propose using Next-Generation Sequencing (NGS) in a One Health Approach to determine the spread of AMR and identify the threats in North Lebanon.
Methods: A total of 83 samples was received from wild animals, sewage, water, and soil samples. Samples were streaked on MacConkey agar plates supplemented with meropenem. Identification of bacterial spp. was primarily done by API20E for all isolated bacteria. Antimicrobial Susceptibility profile was determined by disk diffusion against 5 different antimicrobial agents. Carbapenem resistant Gram- negative bacteria were further characterized by Whole genome sequencing. Bacterial type, international clone, sequence type, resistance genes, and plasmids were detected using sequence data.
Results: We successfully isolated 76 bacterial isolates from different samples. The most common were E. coli (14 %), Pseudomonas spp. (33 %), and Acinetobacter baumanii (8.7 %). Disk diffusion results showed high resistance to meropenem among identified bacterial organisms which is about 75.5 %. Sequence results detected the presence of E. coli strains harboring NDM-5 along with IncFIA, IncFIB (AP001918), IncFII, IncI2(Delta), Incl (Gamma), IncY plasmids. E. coli strains were of ST 405 (n=1), ST361 (n=2), and ST648 (n=1). Acinetobacter baumanii detected by sequencing all belongs to ST2 in IC2. Some of these strains harbored both OXA-23 and OXA-66. A key finding in this study was the isolation of MDR E. coli strain harboring both NDM-5 and OXA-1 from wild animal (Otter).
Conclusion: This project effectively isolated Carbapenem resistant Enterobacteriaceae, Acinetobacter baumanii, and Pseudomonas spp. from animals and environmental samples (sewage, soil, water). The detection of similar clones in both environmental and clinical samples explain the possible transmission of ARG among species and across ecosystem which was further validated by the presence of plasmids that are common plasmids to humans
FIELD DEVELOPMENT PLANNING – INTEGRATED DYNAMIC DRILLING SCHEDULE AND WELL TRAJECTORY DESIGN
No full textField Development Planning (FDP) included finding the appropriate location and design of wells, drilling activities schedule, and other infrastructures’ placement (such as drilling centers, gathering centers, processing units and pipelines). It is usually performed to maximize the economic recovery of a hydrocarbon reservoir while minimizing the environmental footprint. Among multiple decisions during this stage, two important factors should be investigated: well placement and scheduling throughout time and wellbore trajectory design. The drilling schedule outlines the ideal timing and order for drilling activities to maximize the return on investments from proven hydrocarbon reserves. Such a plan considers several parameters like the time-lapse reservoir’s physical properties (e.g. fluid saturations), the prescribed number of wells to be drilled at a given time (based on rig availability), and their types (injectors and/or producers).
In this work, we incorporate a drilling schedule module in a field development planning platform, where a specified number and types of predefined wells are set to meet a certain production target rate. The implemented algorithms enable optimal placement of the development wells through time, hence minimizing the number of wells while maximizing the recovery. We build a time-dependent Net Hydrocarbon Thickness Map (NHCTM) that change throughout the life of the hydrocarbon reservoir due to change in fluid saturations. This NHCTM is used to optimally place wells from a drilling schedule. Well trajectories for the proposed wells are then designed and the overall system is modeled using a commercial reservoir simulator that is controlled from the field development planning framework.
This proposed workflow is applied to the Olympus optimization benchmark which illustrates a complex green field development challenge and results are compared to existing “static” well placement optimization results where wells are placed beforehand at the beginning of the life of the oil or gas field