Simulation-based Evaluation of Mobile Ad Hoc Network Routing Protocols: Ad hoc On-Demand Distance Vector, Fisheye State Routing, and Zone Routing Protocol

Mobile ad hoc network (MANET) is an infrastructure-less and decentralized network without any physical connections. Nodes are mobile, free to move, and independent of each other which makes routing a difficult task. Hence, a dynamic routing protocol is needed to make MANET reliable and function properly. Several routing protocols have been proposed with different working mechanisms and performance levels. Therefore, the performance study of those protocols is needed. This paper evaluates the performance of MANET routing protocols using simulation based experiments to observe the behavior of the network as the density of the nodes increases. The paper evaluates the performance of proactive (fisheye state routing), reactive (ad hoc on-demand distance vector), and hybrid (zone routing protocol) routing protocols in terms of the packet delivery fraction, average throughput, and average end-to-end delay. The simulations of protocols to analyze their performance in different conditions were performed using the network simulator 2 (NS 2)

Optoelectronically active sensitisers for the selective detection of nucleic acid biomarkers

This thesis presents biophysical studies of new optoelecronically active DNA-binders. Chapter one gives a brief overview of the importance of DNA in medicine, of DNA structure and of the mode of interactions of small molecules with double-stranded DNA, including electrostatic, intercalation and groove interactions. Various examples of small-molecule binding to DNA are discussed. Additionally, this chapter briefly describes the biophysical techniques which can be exploited to quantify the interaction between small-molecules and duplex DNA. Chapter two describes the results of studies of the interactions of a group of 1,8-naphthalimide derivatives with double-stranded DNA using a variety of techniques viz. spectroscopy, calorimetry, viscosity and molecular docking studies. Additionally, this chapter also presents sequence selectivity studies of this group of compounds for specific sequences (dAdT)12●(dAdT)12 and (dGdC)12●(dGdC)12 through UV-visible spectroscopy. The 1,8-napthtalimide unit is shown to be a useful element for inducing DNA-binding. Chapter three describes studies of the interactions of a family of dendrimeric compounds with double-stranded DNA, again using spectroscopy, calorimetry, viscosity and molecular docking studies. Furthermore, this chapter includes sequence selectivity studies of this group of compounds for (dAdT)12●(dAdT)12 and (dGdC)12●(dGdC)12 via UV-visible spectroscopy. The charge and the length of the dendritic structures is shown to strongly affect nucleic acid affinities of this series of molecules. Chapter four describes the results of studies of the interactions of miscellaneous compounds with double-stranded DNA using variety of techniques viz. spectroscopy, calorimetry, viscosity and molecular docking studies. In addition, this chapter displays sequence selectivity studies of this group of compounds for specific sequences (dAdT)12●(dAdT)12 and (dGdC)12●(dGdC)12 via UV-visible spectroscopy. Chapter five gives an overview and general conclusions about the DNA binding studies presented in Chapters 2, 3 & 4 and finishes with suggestions for future work

Sustainable performance and disaster management in the oil and gas industry: An intellectual capital perspective

In the post-COVID era and amidst the ongoing Ukraine conflict, the natural resource extraction sector, particularly oil and gas, faces unprecedented challenges in maintaining its sustainability. Disasters in this sector, ranging from environmental catastrophes to operational disruptions, further exacerbate these challenges, eroding environmental integrity and aggravating social issues. These events underscore the urgency of strengthening disaster management capabilities in the oil and gas sector to safeguard against future uncertainties and sustain its operational viability. Against this context, this study aims to examine two critical facets of disaster management in the oil and gas sector. The first objective is to assess the role of intangible resources, particularly intellectual capital, in improving an organization's disaster management capabilities. Intellectual capital, encompassing human, relational, and structural capital, is posited as a key driver in managing complex and unpredictable challenges. The second objective is to investigate the role of supply chain risk management in mediating the impact of intellectual capital on disaster management. Data for this study were collected from firms in the oil and gas sector of Pakistan through a structured questionnaire Partial Least Squares Structural Equation Modeling (PLS-SEM) was employed for data analysis. The results reveal a significant impact of intellectual capital on improving both the responsiveness and alertness aspects of disaster management. Further, supply chain risk management emerges as a crucial factor in channeling the influence of intellectual capital on disaster management effectiveness. Findings of the study not only contributes to the theoretical understanding of disaster management in the natural resource sector but also offers practical insights for industry practitioners. The novelty of this study lies in its empirical examination of the interplay between intellectual capital, supply chain risk management, and disaster management capabilities, win the context of the oil and gas sector

The Effect of Adding Stiffener on Deflection of Loading Arm by Using BEM & FEM

In this study we are concerned to improve the deflection of the loading arm with new suggested style , where the BEM techniques has been used to estimate a deflection at each distance (x) for the main part of loading arm pipe (3'') , thereafter a simplified stiffener has been added to optimize a moment of inertia of this main part thereby the deflection will be better , for this purpose a case study has been considered according to international standard for the pipe specification that  investigated to illustrate the goal of this work, adding to this ANSYS  program  has been used to verify the calculation

Chansu inhibits the expression of cortactin in colon cancer cell lines in vitro and in vivo

Background: Chansu is a transitional Chinese medicine that has been used for centuries as therapy for inflammation, anaesthesia and arrhythmia in China and other Asian countries. Recently, it has also been used for anti-cancer purposes. We have previously shown that Chansu has a huge pro-apoptotic potential on colon cancer cells, but to date the detailed mechanism of this action is not well understood. Methods: One of the major components of Chansu, Cinobufagin (CBF) was used to treat cancer cells. The expressions of levels of cortactin, an important factor in tumour progression and cancer invasion, were assessed in in vitro and in vivo experiments. Additional analyses were performed in subcellular protein fractions and immune-fluorescent staining was used to define cortactin protein expression and the changes of location in CBF-treated cells. Results: CBF strongly inhibited the expression of cortactin in HCT116 cells. There were reductions of both mRNA transcription and protein synthesis, which were more significant in the absence of oxygen in vitro. In addition, nuclear translocation of cortactin was observed in HCT116 cells post CBF exposure but not in the negative control, indicating that CBF is likely to interrupt co-localisation of cortactin to cytoskeletal proteins. Most importantly, CBF could diminish the expression of cortactin in human HCT116 xenograft tumours in nude mouse in vivo. Conclusions: CBF inhibits cortactin expression and nuclear translocation in colon cancer cells in vitro and in mouse models bearing human colon tumour in vivo, suggesting it might disrupt actin-regulated cell movement. Thus, CBF or Chansu could be developed as an effective anti-cancer therapy to stop local invasion and metastasis

The mechanisms of Chansu in inducing efficient apoptosis in colon cancer cells

Chansu is one of the most widely used traditional Chinese medicines in China, Japan, and other Southeast Asian countries primarily for antipain, anti-inflammation, and recently anticancer. Over 10 recipes and remedies contained Chansu, which are easily available in pharmacies and hospitals, but the mechanisms of action were not clearly articulated. In the present study, Cinobufagin (CBF), the major compound of Chansu, was employed as a surrogate marker to determine its ability in inducing cancer cell death. As expected, CBF has significant cancer-killing capacity for a range of cancers, but such ability differs markedly. Colon and prostate cancers are more sensitive than skin and lung cancers. Interestingly, cancer cells die through apoptotic pathway either being biphasic caspase- 3-dependent (HCT116) or independent (HT29). Multipathway analysis reveals that CBF-induced apoptosis is likely modulated by the hypoxia-inducing factor-1 alpha subunit (HIF-

A surgical technology comparison between belarus and Yemen [comparative study]

This comparative study aims to analyze and compare the state of surgical technology in Belarus and Yemen. By examining the current advancements, challenges, and healthcare infrastructure in each country, this article provides insights into the similarities and differences in surgical technology adoption and implementation. The study highlights the importance of technological advancements in improving surgical outcomes and discusses potential strategies for bridging the technological gap between the two countries. The findings of this study can inform policymakers and healthcare professionals in Belarus and Yemen as they work towards enhancing surgical care and patient outcomes