Green synthesis, characterization and biofunctionalisation of nanoparticles for medical applications

In the presented work, the phytochemicals existent in the aqueous extract of (Hypericum perforatum L.) St. John's wort was harnessed to prepare silver nanoparticles. Many conditions have been tried and changed until we reached the final protocol, through which we obtained the desired nanoparticles in terms of size, shape and effectiveness. The organic compounds present in the St. John's wort plant played an important role in reducing the silver ions in the solution to metallic silver, as well as in protecting the formed silver nanoparticles in nano dimensions and preventing them from growing to millimeter dimensions by forming a protective layer on the surfaces of these nanoparticles and finally maintaining the stability of these formed nanoparticles in colloidal solutions. This green chemistry approach for the preparation of AgNPs is a simple, safe, sustainable, credible and eco-friendly protocol and the resulting silver nanoparticles are considered promising for later application in the treatment of various infectious and non-communicable diseases. green synthesized silver nanoparticles have been characterized using various techniques such as ultraviolet-visible spectroscopy (UV-Vis), dynamic light scattering (DLS), zeta potential, Fourier transform infrared (ATR-FTIR) spectroscopy, X-Ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), energy dispersive X-Ray (EDX), nanoparticle tracking analysis (NTA), atomic force microscopy (AFM), thermogravimetric analysis (TGA) and atomic absorption spectroscopy (AAS), and all results proved that biosynthesized silver nanoparticles are spherical in shape, stable in colloidal solution, the size of their particles ranges between 20 to 50 nm, have a face-centered cubic (fcc) and crystalline in nature and on the surfaces of these particles, there is a protective layer consisting of a group of St. John's wort compounds, the percentage of which varies according to the number of washing times. It is known that reducing agents and the chemical composition of nanoparticle surfaces are the most influential factors in determining the activity and toxicity of these nanoparticles later because they affect cellular uptake, biodistribution, penetration into biological barriers and the resulting therapeutic effects. Therefore, the second objective of this study was to identify the organic compounds from the aqueous extract of the St. John’s wort, which is present on the surfaces of silver nanoparticles as a protective agent. To achieve this goal, it was necessary to analyze the plant itself, i.e. develop a protocol in HPLC to separate the components of the extracts for this plant well. The aerial parts of the plant were extracted using 8 different solvents. A simple protocol has been developed to obtain isolated peaks in the HPLC spectrum. Detection was carried out at 260 for phloroglucinols (Hyperforin and derivates), 350 for Flavonols and 590 nm for naphthodianthrones (Hypericins). Various standards were selected for this, which also represent the most important and best-known compounds of St. John's wort and the mass spectrometric analysis in positive ion mode was performed to allow in-line analysis coupled directly to the HPLC system used for the separation of the molecular ions according to mass to charge (m/z). Finally, the major ingredients (Hyperforin, Adhyperforin, Hypericin, Rutin, Quercetin, Quercitrin, Quercitrin-hydrate, Hyperoside, Biapigenin and Chlorogenic acid) have been identified. Total phenolic, antioxidant activity (DPPH and ABTS assays.) and their relationship for different extracts were also presented in this study. In another study, the layer on the surfaces of silver nanoparticles was isolated using a mixture of solvents and following a specific protocol. After that, LC–ESI-Q-TOF–MS/MS analysis was carried out to determine these substances, and they have already been identified, which are 1=Neochlorogenic acid; 2=Hyperoside; 3=Isoquercitrin; 4=l3,II8-biapigenin; 5=Furohyperforin; 6= Hyperforin; 7=Furoadhyperforin; 8=Adhyperforin. Antioxidant activity of the biologically prepared AgNPs was studied using 3 different methods: DPPH, ABTS and SO assays, and the results were very impressive and better than all that was mentioned by other researchers. The antimicrobial effect on about 20 types of microbes (Gram-positive bacteria, Gram-negative bacteria, Pathogenic yeast and leishmaniasis tropica Syrian strain (LT_SYR_24)) has been studied in multiple areas and using different methods. In fact, the results were very excellent compared to antibiotics, silver nitrate, as well as silver nanoparticles prepared by other researchers, as they were mostly lethal at very low concentrations. Anti-cancer activity against 3 types (Hela, Hep G2 and A549 cells) at various concentrations and various exposure times, and the results were very distinctive and promising for use as a future treatment for cancer. After the prepared silver nanoparticles achieved great success in treating different types of cancer cells, the last and most important step was how to modify these particles to be selectivity, that is, when injected in vivo, they go directly to the tumor or cancer cells without affecting healthy cells. Since oligonucleotide-based aptamers (APTs) are excellent ligands for targeting cancer cells, we have already developed a special protocol to conjugate silver nanoparticles prepared in our method with a specific aptamer as a selective targeting part for uptake by A549 cells. Many conditions and factors have been tried to reach a high coupling ratio without affecting the effectiveness of the aptamer. the cytotoxicity of aptamer-conjugated AgNPs against A549 (human non-small cell lung cancer) and BEAS-2B (normal human bronchial epithelial ) were studied using CTB test, cellular uptake, viability staining (using Calcein AM and Propidium Iodide), Quantitation of Apoptosis and Necrosis cells (using Annexin V and Propidium Iodide) and Cellular morphological changes (laser scanning confocal microscope and normal microscope). All results indicated that the effect of aptamer conjugated AgNPs was very large on cancer cells (A549 cells) compared to healthy cells (BEAS2B) at the same or lesser concentrations. This indicates that these nanoparticles exhibited selective binding and internalization to target A549 cells, but not by normal human bronchial epithelium BEAS2B, thus exhibiting high selective specificity

To Be Ethical Or Not To Be: An International Code Of Ethics For Leadership

To be ethical or not to be that is the question? Leadership is about setting the right example and making a difference in people's lives. You do not have to do great things to make a difference (Ayres, 2004). Honesty, tell the truth no matter what, respect, punctuality, not judgmental, just, humble, and dignity can be international code of ethics every leader should follow. Much has changed in our world in the past several decades including people’s beliefs of what is right and wrong. Have their ethics changed as well? This paper introduces an international code of ethics that can guide all different international leadership styles. What is the definition of Ethical Leadership? How can we introduce an international code of ethics for leadership? Finally, leadership is all about example. While an extensive review of literature was not conducted, this researcher was unable to identify an international code of ethics for leadership. Consequently, it is the opinion of this researcher that the following leader characteristics may apply beyond international and cultural boundaries in most instances— honesty, tell the truth no matter what, respect, punctuality, not judgmental, just, humble, and dignity

Using Low-cost IoT-based inclinometers for damage detection of a Bridge model

Nowadays, researchers are paying close attention to using inclinometers for Structural Health Monitoring (SHM) applications. Moreover, the applications based on using inclinometers can detect the magnitude and location of bridge pathologies. However, as these applications are based on expensive commercial inclinometers, their use is typically exclusive to the SHM of structures with a high monitoring budget. There is a gap in the literature with the development and validation of low-cost accurate angular-meters for decreasing the monitoring cost of inclinometer-based damage detection applications. This work aims to develop low-cost IoT-based inclinometers for detecting damage in bridge structures. The Low-cost Adaptable Reliable Angle-meter (LARA) is a novel inclinometer that accurately measures an induced inclination by combining the measurements of five gyroscopes and five accelerometers. The accuracy, resolution, Allan variance, and standard deviation of LARA are examined through laboratory experiments and are compared with those obtained by numerical slope calculations and a commercial inclinometer (HI-INC). For further experimental validation, a robotic vehicle model is designed and developed to simulate a moving load over a bridge model. The vehicle model integrates IoT technology and can be utilized in different damage detection experiments. The outcomes of a load test experiment using a simple beam model demonstrate the high accuracy (0.003 degrees) of LARA measurements. LARA may be used for structural damage identification and location in bridges utilizing inclinometers because of its low cost and high accuracy

An Investigation of Academic Integrity in Jordanian Universities

This study aimed to describe current practices employed by public and private four-year universities in Jordan in promoting academic integrity and addressing academic dishonesty. This quantitative research provided a framework for the current practices that promote academic integrity in higher education in the Middle Eastern country of Jordan. The survey questionnaire developed by Kibler (1992) was utilized to collect data to answer the research questions. This instrument was tested for reliability and validity by Kibler (See Appendix C). In addition, the Cronbach\u27s Alpha was utilized later to check for reliability. The Cronbach\u27s Alpha for the data collected was 0.85. The items included in the questionnaire were constructed to ensure that each item could be measured by using specific criteria. The survey was distributed to 242 (N) participants. Sixty (60) participants completed the survey, which represented a response rate of 25%. In order to analyze the descriptive profile of the 60 participants, all deans and associate deans, a frequency distribution was determined for types of institution, public, and private. Of the participants, 21 were serving in four-year private colleges, while 39 were serving in four year public colleges. The data collected from the deans and associate deans indicated that not all of their institutions have policies that promote academic integrity and address academic dishonesty. In addition, the data received indicated that the mean number of cases of academic dishonesty of the universities that offered educational programs and training were statistically significantly different from universities that did not offer educational programs and training

REVIEW OF OXIDATIVE STRESS AND ANTIOXIDATIVE

Oxidative stress is one of the causative factors of many diseases. According to the pathophysiology, monocytes, macrophages, and normal white cells are produced in large quantities that produce reactive oxygen species (ROS) as well as cytokines that can stimulate cell and tissue damage. Oxidative stress occurs when there is an imbalance between free radicals and antioxidants within the body. ROS (free radicals) are produced by normal cellular metabolism and interact with biomolecules such as protein, lipids, and DNA to cause cellular damage and are responsible for degenerative changes. These processes are responsible for causing many diseases such as cardiovascular diseases. The agents responsible for this damage are reactive oxygen and nitrogen species resulting from various processes that destroy intracellular components such as nucleic acids, proteins, and lipids. These agents can lead to necrotic cell death or apoptosis by activating specific intracellular signaling pathways

Measuring financial reporting quality of non-financial firms listed in Amman Stock Exchange

Purpose- The purpose of this study is to measure financial reporting quality of non-financial firms listed in ASE. As the financial information accuracy and transparency is vital for internal and external users, this study insures that financial reporting quality and financial information published for non-financial firms in ASE is not manubulated, accurate, combitable, timely published, adequate, and free of earning management, to be usefull for decision making for all users, especially for new investors. Methodology- The period 2010 – 2019 forms the data for the statistical analysis. In addition, and to measure the FRQ, the paper uses time series analysis techniques, including descriptive analysis, frequencies and multiple OLS regression were used. Using data from 910 firm-years observation of companies listed on Amman Stock Exchange for the period of 2010 to 2019. Findings- The analysis reveals that The probability for F-Statistics < 0.05, this led to accept the statistical model. on the other hand, R square is 31.3 % which means that the explanatory power of modified Jones model (Dechow et al., 1995) reach 31.3% in explain the practices of earnings management in Jordanian companies. on the other hand, the VIF values are lower than 10 and tolerances higher than 10% which mean there is no multicollinearity problem in the model. as for the 1/A_(i,t-1) shows a significant and negative relationship with total accruals, were 〖∆(Sales-AR)〗_it/A_(i,t-1) and 〖PPE〗_it/A_(i,t-1) 1/A_(i,t-1) shows a significant and positive relationship with total accruals. Conclusion- the highest number of companies practicing earnings management in the year (2012 and 2014) was 60%, while the lowest number of companies that practice earnings management in the year (2015) and it was 32%, on the other hand, the highest number of companies do not practicing earnings management in the year (2015) was 68%, while the lowest number of companies that do not practice earnings management in the year (2012 and 2014) and it was 40%.Publisher's Versio