55 research outputs found
Evaluation of antifungal and antibacterial activities of monoesters of succinic anhydride
Monoester of succinic acid (1-29), synthesised and characterised at our laboratory, were investigated with reference to their antifungal and antibacterial activities. The results concluded that though almost all the compounds were bioactive but the degree of activity was dependent over the substituent attached to benzyl group and order of their bioactivity was iodo > chloro > methoxy > nitro substituted monoesters against the considered microbes. KEY WORDS: Succinic anhydride, Aryl alcohols, Monoesters of succinic acid, Antifungal and antibacterial activity Bull. Chem. Soc. Ethiop. 2014, 28(1), 131-136.DOI: http://dx.doi.org/10.4314/bcse.v28i1.1
Road Traffic Accident Analysis and Identification of Black Spot Locations on Highway
Road safety is the main problem in developing countries. Every year, millions of people die in road traffic accidents, resulting in huge losses of humankind and the economy. This study focuses on the road traffic accident analysis and identification of black spots on the Lahore-Islamabad Highway M-2. Official data of road traffic accidents were collected from National Highway and Highway Police (NH & MP) Pakistan. The data was digitized on MS Excel and Origin Pro. The accident Point weightage (APW) method was employed to identify the black spots and rank of the top ten black spots. The analysis shows that the trend of road traffic accidents on M-2 was characterized by a high rate of fatal accidents of 35.3%. Human errors account for 66.8% as the major contributing factors in road traffic accidents, while vehicle errors (25.6%) and environmental factors (7.6%) were secondary and tertiary contributing factors. The main causes of road traffic accidents were the dozing on the wheel (27.9%), the careless driving (24.6%), tyre burst (11.7%), and the brakes failure (7.4%). Kallar Kahar (Salt Range) was identified as a black spot (223 km, 224 km, 225 km, 229 km, and 234 km) due to vehicle brake failure. The human error was a major contributory factor in road traffic accidents, therefore public awareness campaign on road safety is inevitable and use of the dozen alarm to overcome dozing on the wheel. Doi: 10.28991/cej-2020-03091629 Full Text: PD
Detection and Antibiotic Susceptibility Pattern of Biofilm Producing Gram Positive and Gram Negative Bacteria Isolated From a Tertiary Care Hospital of Pakistan
Microorganisms adhere to non-living material or living tissue, and form biofilms made up of extracellular polymers/slime. Biofilm-associated microorganisms behave differently from free-floating bacteria with respect to growth rates and ability to resist antimicrobial treatments and therefore pose a public health problem. The objective of this study is to detect the prevalence of biofilm producers among Gram positive and Gram negative bacteria isolated from clinical specimens, and to study their antimicrobial susceptibility pattern. The study was carried out from October 2009 to March 2010, at the Department of Microbiology, Army Medical College/ National University of Sciences and Technology (NUST), Rawalpindi, Pakistan. Clinical specimens were received from various wards of a tertiary care hospital. These were dealt by standard microbiological procedures. Gram positive and Gram negative bacteria isolated were subjected to biofilm detection by congo red agar method (CRA). Antimicrobial susceptibility testing of those isolates, which showed positive results (slime production), was done according to the Kirby-Bauer disc diffusion technique. A total of 150 isolates were tested for the production of biofilm/slime. Among them, 81 isolates showed positive results. From these 81, 51 were Gram positive and 30 were Gram negative. All the 81(54%) slime producers showed reduced susceptibility to majority of antibiotics. Bacterial biofilms are an important virulence factor associated with chronic nosocomial infection. Detection of biofilm forming organisms can help in appropriate antibiotic choice
Imaging the scattering field of a single GaN nanowire
In this work, a single gallium nitride (GaN) nanowire has been examined by our previously reported technique parametric indirect microscopic imaging (PIMI). Mapping of the nanoscale scattering signals from GaN nanowire has been achieved with PIMI system. A comparison with classical far field microscopy and FDTD simulations is included to show the relevant differences and the strength of this technique. In PIMI, highly defined modulated illumination, far field variation quantification, and filtering process resolve the nanoscale scattering field distribution in the form of polarization parameters. We believe that our system provides us a platform to understand the physics of these nanoscale scattering fields from optical nanoantennas.The authors wish to acknowledge the financial support National Key Research and Development Program of China (2017YFF0107100), National Natural Science Foundation of China (NSFC) (61501239), NSFC-2017 (International Young Scientist Research Fund No. 61750110520) and the 'Zijin Professor Project' of Nanjing University of Science and Technology. B G C wants to thank the financial support from Agencia Estatal de Investigación and FEDER for the Project TEC2016-77242-C3-1-R AEI/FEDER, UE and Comunidad de Madrid for the SINFOTON-CM Research Program (S2013/MIT-2790).Publicad
Effect of Job Environment on Pulmonary Functions of Railway Employees
Background: To seek relationship between job related exposure of Pakistan Railways workers and the development of respiratory diseases. Methods: One hundred (100) exposed railway workers and a reference group of 100 office workers were recruited in the study. Respiratory symptoms, smoking habits, physical examination findings, chest x-ray and spirometry results were recorded on standard proforma. Results: The FEV1/FVC ratio was significantly lower in the Railway workers than in the reference group (p<0.001). Exposed Railway employees had significantly high (p<0.001) incidence of pulmonary diseases as compared to the reference group. Disproportionately higher incidence of chronic obstructive airway disease was observed in the exposed Railway employees who smoked as compared to the non-smokers in the same group (p<0.001). Conclusion: In exposed Railway workers there is an increased risk of respiratory symptoms, decline in lung functions and chronic obstructive pulmonary disease (COPD) as compared to referents. There is disproportionately higher incidence of COPD among the smokers in the Railway workers as compared to the non-smokers in the same group
Modelling, Simulation, and Control of a Flexible Space Launch Vehicle
Modern Space Launch Vehicles (SLVs), being slender in shape and due to the
use of lightweight materials, are generally flexible in nature. This structural
flexibility, when coupled with sensor and actuator dynamics, can adversely
affect the control of SLV, which may lead to vehicle instability and, in the
worst-case scenario, to structural failure. This work focuses on modelling and
simulation of rigid and flexible dynamics of an SLV and its interactions with
the control system. SpaceX's Falcon 9 has been selected for this study. The
flexible modes are calculated using modal analysis in Ansys. High-fidelity
nonlinear simulation is developed which incorporates the flexible modes and
their interactions with rigid degrees of freedom. Moreover, linearized models
are developed for flexible body dynamics, over the complete trajectory until
the first stage's separation. Using classical control methods, attitude
controllers, that keep the SLV on its desired trajectory, are developed, and
multiple filters are designed to suppress the interactions of flexible
dynamics. The designed controllers along with filters are implemented in the
nonlinear simulation. Furthermore, to demonstrate the robustness of designed
controllers, Monte-Carlo simulations are carried out and results are presented.Comment: Presented at 20th International Bhurban Conference on Applied
Sciences and Technology (IBCAST), 202
Mechanical Performance of Polymeric ARGF-Based Fly Ash-Concrete Composites: A Study for Eco-Friendly Circular Economy Application
At present, low tensile mechanical properties and a high carbon footprint are considered the chief drawbacks of plain cement concrete (PCC). At the same time, the combination of supplementary cementitious material (SCM) and reinforcement of fiber filaments is an innovative and eco-friendly approach to overcome the tensile and environmental drawbacks of plain cement concrete (PCC). The combined and individual effect of fly ash (FA) and Alkali resistance glass fiber (ARGF) with several contents on the mechanical characteristics of M20 grade plain cement concrete was investigated in this study. A total of 20 concrete mix proportions were prepared with numerous contents of FA (i.e., 0, 10, 20, 30 and 40%) and ARGF (i.e., 0, 0.5, 1 and 1.5%). The curing of these concrete specimens was carried out for 7 and 28 days. For the analysis of concrete mechanical characteristics, the following flexural, split tensile, and compressive strength tests were applied to these casted specimens. The outcomes reveal that the mechanical properties increase with the addition of fibers and decrease at 30 and 40% replacement of cement with fly ash. Replacement of cement at higher percentages (i.e., 30 and 40) negatively affects the mechanical properties of concrete. On the other hand, the addition of fibers positively enhanced the flexural and tensile strength of concrete mixes with and without FA in contrast to compressive strength. In the end, it was concluded that the combined addition of these two materials enhances the strength and toughness of plain cement concrete, supportive of the application of an eco-friendly circular economy. The relationship among the mechanical properties of fiber-reinforced concrete was successfully generated at each percentage of fly ash. The R-square for general relationships varied from (0.48–0.90) to (0.68–0.96) for each percentage of FA fiber reinforced concrete. Additionally, the accumulation of fibers effectively boosts the mechanical properties of all concrete mixes.publishedVersio
Agricultural trade, foreign direct investment and inclusive growth in developing countries: evidence from West Africa
This study examines how agricultural trade and Foreign Direct Investment (FDI) influence inclusive growth in developing countries, using the case of West Africa. It engages data obtained from various World Bank sources for 15 West African countries that are members of the Economic Community of West African States (ECOWAS) for the period 2000–2019. The study calculates inclusive growth using the Principal Component Analysis (PCA) and applies the Two-
stage Least Squares (2SLS) to resolve the possible issue of endogeneity. The findings show, among others, that agricultural trade is significant in explaining the level of inclusive growth. It implies that a 1% increase in agricultural trade may increase inclusive growth by 0.88% (first stage) and 0.99% (second stage), respectively. In contrast, FDI is insignificant in explaining inclusive growth. Therefore, the study recommends that effective policies such as flexible trade policies to enhance the exchange of goods and services should be implemented, which is crucial given the need for more resilience in post-COVID-19 ECOWAS
Three-Pond Model with Fuzzy Inference System-Based Water Level Regulation Scheme for Run-of-River Hydropower Plant
Power generation from river hydropower plants depends mainly on river flow. Water fluctuations in the river make the yield process unpredictable. To reduce these fluctuations, building a small reservoir at the river flow of the hydropower plant is recommended. Conventionally, classic single-pond models are commonly used to design run-of-river hydropower plants. However, such models are associated with fluctuations, sagging, and irregular power fluctuations that lead to irregular water fluctuations. This research proposes a novel idea to replace the single-pond model with a three-pond model to increase the plant’s overall efficiency. The three-pond model is developed as a three-tank nonlinear hydraulic system that contains the same amount of water as a conventional single pond. It also has the advantage of minimizing the run-of-river power plant’s dependence on river flow and increasing efficiency by trapping swell and turbulence in the water. To further increase the efficiency, the developed model was tested for smooth and effective level control using fuzzy control.publishedVersionPeer reviewe
Terminal Galactose as Cancer Recognition Marker: Computing Analysis With Implications of Vicinal Sugars, Linkage and Anomery
Abstract.-Carbohydrate structures on proteins play vital role as recognition markers in several diseases including cancer. The carbohydrate chains are dramatically altered in cancer cells compared to normal cells, both in structure and quantity. The mucin O-glycans show several cancer associated structures like T-(Gal-GalNAc-Ser/Thr) and Tn-antigen (GalNAc-Ser/Thr). Terminal galactose (Gal) in mucin type O-glycan oligosaccharide structures is known to act as a recognition marker for several cancer-associated lectins like galectin and mistletoe lectins. This study describes the role of terminal Gal, inclusive of its anomery, linkage and that of sugar residues vicinal to terminal Gal in oligosaccharide structures of glycoproteins, as an epitope or as a recognition marker in cancer
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