Search results for: biological events

Authors: Ihab Elaff

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Simulating the heart’s electrical stimulation is essential in modeling and evaluating the electrophysiology behavior of the heart. For achieving that, there are two structures in concern: the ventricles’ Myocardium, and the ventricles’ Conduction Network. Ventricles’ Myocardium has been modeled as anisotropic material from Diffusion Tensor Imaging (DTI) scan, and the Conduction Network has been extracted from DTI as a case-based structure based on the biological properties of the heart tissues and the working methodology of the Magnetic Resonance Imaging (MRI) scanner. Results of the produced activation were much similar to real measurements of the reference model that was presented in the literature.

Keywords: diffusion tensor, DTI, heart, conduction network, excitation propagation

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Authors: Mohammad Kazem Mohammadi

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The use of anticancer agents forms an important part of the treatment of cancer of various types. Uranyl Complexes with DPHMP ligand have been used for the prevention and treatment of cancers. U(IV) metal complexes prepared by reaction of uranyl salt UO2 (NO3)2.6H2O with DPHMP in dry acetonitrile. Characterization of the ligand and its complexes was made by microanalyses, FT-IR, 1H NMR, 13C NMR and UV–Visible spectroscopy. These new complex showed excellent antitumor activity against two kinds of cancer cells that that are HT29:Haman colon adenocarcinoma cell line and T47D:human breast adenocarcinoma cell line.

Keywords: uranyl complexes, DPHMP ligand, antitumor activity, HT29, T47D

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Authors: Charalabos Antonatos, Mariza Panoutsopoulou, Georgios K. Georgakilas, Evangelos Evangelou, Yiannis Vasilopoulos

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The extended tissue damage and severe clinical outcomes of autoimmune diseases, accompanied by the high annual costs to the overall health care system, highlight the need for an efficient therapy. Increasing knowledge over the pathophysiology of specific chronic inflammatory diseases, namely Psoriasis (PsO), Inflammatory Bowel Diseases (IBD) consisting of Crohn’s disease (CD) and Ulcerative colitis (UC), and Rheumatoid Arthritis (RA), has provided insights into the underlying mechanisms that lead to the maintenance of the inflammation, such as Tumor Necrosis Factor alpha (TNF-α). Hence, the anti-TNFα biological agents pose as an ideal therapeutic approach. Despite the efficacy of anti-TNFα agents, several clinical trials have shown that 20-40% of patients do not respond to treatment. Nowadays, high-throughput technologies have been recruited in order to elucidate the complex interactions in multifactorial phenotypes, with the most ubiquitous ones referring to transcriptome quantification analyses. In this context, a random effects meta-analysis of available gene expression cDNA microarray datasets was performed between responders and non-responders to anti-TNFα therapy in patients with IBD, PsO, and RA. Publicly available datasets were systematically searched from inception to 10th of November 2020 and selected for further analysis if they assessed the response to anti-TNFα therapy with clinical score indexes from inflamed biopsies. Specifically, 4 IBD (79 responders/72 non-responders), 3 PsO (40 responders/11 non-responders) and 2 RA (16 responders/6 non-responders) datasetswere selected. After the separate pre-processing of each dataset, 4 separate meta-analyses were conducted; three disease-specific and a single combined meta-analysis on the disease-specific results. The MetaVolcano R package (v.1.8.0) was utilized for a random-effects meta-analysis through theRestricted Maximum Likelihood (RELM) method. The top 1% of the most consistently perturbed genes in the included datasets was highlighted through the TopConfects approach while maintaining a 5% False Discovery Rate (FDR). Genes were considered as Differentialy Expressed (DEGs) as those with P ≤ 0.05, |log2(FC)| ≥ log2(1.25) and perturbed in at least 75% of the included datasets. Over-representation analysis was performed using Gene Ontology and Reactome Pathways for both up- and down-regulated genes in all 4 performed meta-analyses. Protein-Protein interaction networks were also incorporated in the subsequentanalyses with STRING v11.5 and Cytoscape v3.9. Disease-specific meta-analyses detected multiple distinct pro-inflammatory and immune-related down-regulated genes for each disease, such asNFKBIA, IL36, and IRAK1, respectively. Pathway analyses revealed unique and shared pathways between each disease, such as Neutrophil Degranulation and Signaling by Interleukins. The combined meta-analysis unveiled 436 DEGs, 86 out of which were up- and 350 down-regulated, confirming the aforementioned shared pathways and genes, as well as uncovering genes that participate in anti-inflammatory pathways, namely IL-10 signaling. The identification of key biological pathways and regulatory elements is imperative for the accurate prediction of the patient’s response to biological drugs. Meta-analysis of such gene expression data could aid the challenging approach to unravel the complex interactions implicated in the response to anti-TNFα therapy in patients with PsO, IBD, and RA, as well as distinguish gene clusters and pathways that are altered through this heterogeneous phenotype.

Keywords: anti-TNFα, autoimmune, meta-analysis, microarrays

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Authors: Emad Kouhestani

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Background: Despite the enormous success of anterior cruciate ligament (ACL) reconstruction, acute neuropathic pain can develop postoperatively and is both distressing and difficult to treat once established. Pregabalin, as an anticonvulsant agent that selectively affects the nociceptive process, has been used as a pain relief agent. The purpose of this systematic review of randomized controlled trials (RCTs) was to evaluate the pain control effect of pregabalin versus placebo after ACL reconstruction. Method: A search of the literature was performed from inception to June 2022, using PubMed, Scopus, Google Scholar, Web of Science, Cochrane, and EBSCO. Studies considered for inclusion were RCTs that reported relevant outcomes (postoperative pain scores, or cumulative opioid consumption, adverse events) following the administration of pregabalin in patients undergoing ACL reconstruction. Result: Five placebo-controlled RCTs involving 272 participants met the inclusion criteria. 75 mg and 150 mg of oral pregabalin were used in included trials. Two studies used a single dose of pregabalin one hour before anesthesia induction. Two studies used pregabalin 1 hour before anesthesia induction and 12 hours after. One study used daily pregabalin 7 days before and 7 days after surgery. Out of five papers, three papers found significantly lower pain intensity and cumulative opioid consumption in the pregabalin group compared with the placebo group. However, a decrease in pain scores was found in all trials. Pregabalin administration was associated with dizziness and nausea. Conclusion: The use of pregabalin may be a valuable asset in pain management after ACL reconstruction. However, future studies with larger sample sizes and longer follow-up periods are required.

Keywords: pregabalin, anterior cruciate ligament, postoperative pain, clinical trial

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Authors: Anderson Rocha-Buelvas, Jaqueline Mena Huertas, Edith Burbano Rosero, Arsenio Hidalgo Troya, Mauricio Casas Cruz

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COVID-19 is a disruptive pandemic for the public health and economic system of whole countries, including Colombia. Nariño Department is the southwest of the country and draws attention to being on the border with Ecuador, constantly facing demographic transition affecting infections between countries. In Nariño, the early routine diagnosis of SARS-CoV-2, which can be handled at BSL-2, has affected the transmission dynamics of COVID-19. However, new emerging and re-emerging viruses with biological flexibility classified as a Risk Group 3 agent can take advantage of epidemiological opportunities, generating the need to increase clinical diagnosis, mainly in border regions between countries. The overall objective of this project was to assure the quality of the analytical process in the diagnosis of high biological risk pathogens in Nariño by building a laboratory that includes biosafety level (BSL)-2 and (BSL)-3 containment zones. The delimitation of zones was carried out according to the Verification Tool of the National Health Institute of Colombia and following the standard requirements for the competence of testing and calibration laboratories of the International Organization for Standardization. This is achieved by harmonization of methods and equipment for effective and durable diagnostics of the large-scale spread of highly pathogenic microorganisms, employing negative-pressure containment systems and UV Systems in accordance with a finely controlled electrical system and PCR systems as new diagnostic tools. That increases laboratory capacity. Protection in BSL-3 zones will separate the handling of potentially infectious aerosols within the laboratory from the community and the environment. It will also allow the handling and inactivation of samples with suspected pathogens and the extraction of molecular material from them, allowing research with pathogens with high risks, such as SARS-CoV-2, Influenza, and syncytial virus, and malaria, among others. The diagnosis of these pathogens will be articulated across the spectrum of basic, applied, and translational research that could receive about 60 daily samples. It is expected that this project will be articulated with the health policies of neighboring countries to increase research capacity.

Keywords: medical laboratory science, SARS-CoV-2, public health surveillance, Colombia

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Authors: S. Henine, A. Youkana

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This work is devoted to study the global existence and asymptotic behavior of solutions for Gierer-Meinhardt systems arising in biological phenomena. We prove that the solutions are global and uniformly bounded by a positive constant independent of the time. Our technique is based on Lyapunov functional argument. Under suitable conditions, we established a result on the asymptotic behavior of solutions. These results are valid for any positive continuous initial data, and improve some recently results established.

Keywords: asymptotic behavior, Gierer-Meinhardt systems, global existence, Lyapunov functional

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Authors: Edward Poluyi, Eghosa Morgan, Charles Poluyi, Chibuikem Ikwuegbuenyi, Grace Imaguezegie

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Background: Current epidemiological studies have examined the associations between moderate and severe traumatic brain injury (TBI) and their risks of developing neurodegenerative diseases. Concussion, also known as mild TBI (mTBI), is however quite distinct from moderate or severe TBIs. Only few studies in this burgeoning area have examined concussion—especially repetitive episodes—and neurodegenerative diseases. Thus, no definite relationship has been established between them. Objectives : This review will discuss the available literature linking concussion and amyotrophic lateral sclerosis (ALS) and Alzheimer’s disease (AD). Materials and Methods: Given the complexity of this subject, a realistic review methodology was selected which includes clarifying the scope and developing a theoretical framework, developing a search strategy, selection and appraisal, data extraction, and synthesis. A detailed literature matrix was set out in order to get relevant and recent findings on this topic. Results: Presently, there is no objective clinical test for the diagnosis of concussion because the features are less obvious on physical examination. Absence of an objective test in diagnosing concussion sometimes leads to skepticism when confirming the presence or absence of concussion. Intriguingly, several possible explanations have been proposed in the pathological mechanisms that lead to the development of some neurodegenerative disorders (such as ALS and AD) and concussion but the two major events are deposition of tau proteins (abnormal microtubule proteins) and neuroinflammation, which ranges from glutamate excitotoxicity pathways and inflammatory pathways (which leads to a rise in the metabolic demands of microglia cells and neurons), to mitochondrial function via the oxidative pathways.

Keywords: amyotrophic lateral sclerosis, Alzheimer's disease, mild traumatic brain injury, neurodegeneration

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Authors: Fuad Alzahrani, Yiannis Kyratsis

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Although emergency nurses, being the frontline workers in mass-gatherings, are essential for providing an effective public health response, little is known about the skills that emergency nurses have, or require, in order to respond effectively to a disaster event. This paper is designed to address this gap in the literature by conducting an empirical study on emergency nurses’ preparedness at the mass-gathering event of Hajj in Mecca city. To achieve this aim, this study conducted a cross-sectional survey among 106 emergency department nurses in all the public hospitals in Mecca in 2014. The results revealed that although emergency nurses’ role understanding is high; they have limited knowledge and awareness of how to respond appropriately to mass-gathering disaster events. To address this knowledge gap, the top three most beneficial types of education and training courses suggested are: hospital education sessions, the Emergency Management Saudi Course and workshop; and short courses in disaster management. Finally, recommendations and constructive strategies are developed to provide the best practice in enhancing disaster preparedness. This paper adds to the body of knowledge regarding emergency nurses and mass gathering disasters. This paper measures the level of disaster knowledge, previous disaster response experience and disaster education and training amongst emergency nurses in Mecca, Saudi Arabia. It is anticipated that this study will provide a foundation for future studies aimed at better preparing emergency nurses for disaster response. This paper employs new strategies to improve the emergency nurses’ response during mass gatherings for the Hajj. Increasing the emergency nurses’ knowledge will develop their effective responses in mass-gathering disasters.

Keywords: emergency nurses, mass-gatherings, hajj, disaster preparedness, disaster knowledge, perceived role, disaster training, previous disaster response experience

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Authors: Malani Herath, Sohan Wijesekera, Jagath Munasingha

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The impact of recent floods become significant, and the extraordinary flood events cause considerable damage to lives, properties, environment and negatively affect the whole development of Colombo urban region. Even though the Colombo urban region experiences recurrent flood impacts, several spatial planning interventions have been taken from time to time since early 20th century. All past plans have adopted a traditional approach to flood management, using infrastructural measures to reduce the chance of flooding together with rigid planning regulations. The existing flood risk management practices do not operate to be acceptable by the local community particular the urban poor. Researchers have constantly reported the differences in estimations of flood risk, priorities, concerns of experts and the local community. Risk-based decision making in flood management is not only a matter of technical facts; it has a significant bearing on how flood risk is viewed by local community and individuals. Moreover, sustainable flood management is an integrated approach, which highlights joint actions of experts and community. This indicates the necessity of further societal discussion on the acceptable level of flood risk indicators to prioritize and identify the appropriate flood management measures in Colombo. The understanding and evaluation of flood risk by local people are important to integrate in the decision-making process. This research questioned about the gap between the acceptable level of flood risk to spatial planners and to the local communities in Colombo. A comprehensive literature review was conducted to prepare a framework to analyze the public perception in Colombo. This research work identifies the factors that affect the variation of flood risk and acceptable levels to both local community and planning authorities.

Keywords: Colombo basin, public perception, urban flood risk, multi-criteria analysis

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Authors: Ibrahim Magaji

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WhatsApp messaging platform brings about new opportunities for users to participate in unique storytelling experiences and audience engagement, particularly to Students of Mass communication who receive training to report events and issues accurately and objectively in accordance with official controls. Also, the complex nature of society today made it possible to use the WhatsApp platform that revolutionizes the means of sharing information, ideas, and experiences. This paper examined the WhatsApp messaging platform and how it influenced the academic performance of students in the Department of Mass Communication, Abdu Gusau Polytechnic, Talata Mafara. It used in-depth interview techniques and focus group discussion with students, as well as the use of published materials as well as unpublished materials to gather related and relevant data. Also, the paper used procedures involved to analyze long interview content. This procedure includes observation of a useful utterance, development of expanded observation, the examination of the interconnection of observed comments, collective scrutiny of observation for patterns and themes, and review and analysis of the themes across all interviews for development of the thesis. The result revealed that the majority of students used WhatsApp messenger for making friends and chatting. Also, the students experienced negative effects such as poor grammar and spelling, less study time, and poor academic performance because of active participation in the use of WhatsApp messaging platform. Surprisingly, there was a high addiction rate among students in the usage of WhatsApp messenger. However, other students experienced an improvement in their readings skills as a result of participation in the use of the platform. Also, students shared ideas, discussed, and shared examination questions among themselves on WhatsApp messenger.

Keywords: WhatsApp messenger, students, participation, group

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Authors: Akram Khelaifia, Salah Guettala, Nesreddine Djafar Henni, Rachid Chebili

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Recent seismic events have underscored the significant influence of masonry infill walls on the resilience of structures. The irregular positioning of these walls exacerbates their adverse effects, resulting in substantial material and human losses. Research and post-earthquake evaluations emphasize the necessity of considering infill walls in both the design and assessment phases. This study delves into the presence of soft stories in reinforced concrete structures with infill walls. Employing an approximate method relying on pushover analysis results, fiber-section-based macro-modeling is utilized to simulate the behavior of infill walls. The findings shed light on the presence of soft first stories, revealing a notable 240% enhancement in resistance for weak column—strong beam-designed frames due to infill walls. Conversely, the effect is more moderate at 38% for strong column—weak beam-designed frames. Interestingly, the uniform distribution of infill walls throughout the structure's height does not influence soft-story emergence in the same seismic zone, irrespective of column-beam strength. In regions with low seismic intensity, infill walls dissipate energy, resulting in consistent seismic behavior regardless of column configuration. Despite column strength, structures with open-ground stories remain vulnerable to soft first-story emergence, underscoring the crucial role of infill walls in reinforced concrete structural design.

Keywords: masonry infill walls, soft Storey, pushover analysis, fiber section, macro-modeling

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Authors: Stephen M. Magu

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The 9/11 and Christmas bombing attacks in the United States are mostly associated with the inability of intelligence agencies to connect dots based on intelligence that was already available. The 1998, 2002, 2013 and several 2014 terrorist attacks in Kenya, on the other hand, are probably driven by a completely different dynamic: the invisible hand of corruption. The World Bank and Transparency International annually compute the Worldwide Governance Indicators and the Corruption Perception Index respectively. What perhaps is not adequately captured in the corruption metrics is the impact of corruption on terrorism. The World Bank data includes variables such as the control of corruption, (estimates of) government effectiveness, political stability and absence of violence/terrorism, regulatory quality, rule of law and voice and accountability. TI's CPI does not include measures related to terrorism, but it is plausible that there is an expectation of some terrorism impact arising from corruption. This paper, by examining the incidence, frequency and total number of terrorist attacks that have occurred especially since 1990, and further examining the specific cases of Kenya and Nigeria, argues that in addition to having major effects on governance, corruption has an even more frightening impact: that of facilitating and/or violating security mechanisms to the extent that foreign nationals can easily obtain identification that enables them to perpetuate major events, targeting powerful countries' interests in countries with weak corruption-fighting mechanisms. The paper aims to model interactions that demonstrate the cost/benefit analysis and agents' rational calculations as being non-rational calculations, given the ultimate impact. It argues that eradication of corruption is not just a matter of a better business environment, but that it is implicit in national security, and that for anti-corruption crusaders, this is an argument more potent than the economic cost / cost of doing business argument.

Keywords: corruption, global south, identification, passports, terrorism

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Authors: Majed Sanan, Mohammad Rammal, Wassim Rammal

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Today, security is a major concern. Intrusion Detection, Prevention Systems and Honeypot can be used to moderate attacks. Many researchers have proposed to use many IDSs ((Intrusion Detection System) time to time. Some of these IDS’s combine their features of two or more IDSs which are called Hybrid Intrusion Detection Systems. Most of the researchers combine the features of Signature based detection methodology and Anomaly based detection methodology. For a signature based IDS, if an attacker attacks slowly and in organized way, the attack may go undetected through the IDS, as signatures include factors based on duration of the events but the actions of attacker do not match. Sometimes, for an unknown attack there is no signature updated or an attacker attack in the mean time when the database is updating. Thus, signature-based IDS fail to detect unknown attacks. Anomaly based IDS suffer from many false-positive readings. So there is a need to hybridize those IDS which can overcome the shortcomings of each other. In this paper we propose a new approach to IDS (Intrusion Detection System) which is more efficient than the traditional IDS (Intrusion Detection System). The IDS is based on Honeypot Technology and Anomaly based Detection Methodology. We have designed Architecture for the IDS in a packet tracer and then implemented it in real time. We have discussed experimental results performed: both the Honeypot and Anomaly based IDS have some shortcomings but if we hybridized these two technologies, the newly proposed Hybrid Intrusion Detection System (HIDS) is capable enough to overcome these shortcomings with much enhanced performance. In this paper, we present a modified Hybrid Intrusion Detection System (HIDS) that combines the positive features of two different detection methodologies - Honeypot methodology and anomaly based intrusion detection methodology. In the experiment, we ran both the Intrusion Detection System individually first and then together and recorded the data from time to time. From the data we can conclude that the resulting IDS are much better in detecting intrusions from the existing IDSs.

Keywords: security, intrusion detection, intrusion prevention, honeypot, anomaly-based detection, signature-based detection, cloud computing, kfsensor

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Authors: Anna Stoutenburg

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With the rise of the so-called 'new left' within the United States, marked by social democratic figures such as Bernie Sanders and Alexandria Ocasio-Cortez, significant questions have been raised in response to those who would identify with the term 'socialist'. These queries typically revolve around the negatively perceived legacy of past and present countries that share the term in question, with the stark conclusion that not only is socialism a structure that does not work economically, but that it also tends to inflict more harm on those living under it that would be endured in a country functioning under capitalism. In order to examine these claims, the goal of this paper is to examine the legacy of anti-communist historiography in a western context, with the Union of Soviet Socialist Republics, China, and modern Venezuela used as case studies for how this phenomenon operates. Not only will key portions of each nation’s history be re-examined, but there will also be a critical analysis of source cultivation and usage among western historians. The intent of this paper is not merely to deride previous attempts at historicizing and reporting on the events of the nations, but rather to attempt to glean a clearer picture that is free from anti-communist sentiments. Theoretical works that will be consulted in order to define this project are 'The Historiography of Communism' by Michael Brown, as well as 'Beyond Philosophy: Ethics, History, Marxism, and Liberation Theology' by Enrique Dussel. The latter will provide insights concerning why these questions are relevant in a larger context, namely by articulating how the means of liberation understood through an analectic method can be achieved structurally. For a majority of leftists, this question is integral, and by using history as a tool, the ways that political organizing can be used can be better understood, bridging the gap between the common assumption that the communist legacy is a dire one and the idea that it is something which needs to be completely lauded.

Keywords: anti-communism, history, ideology, Marxism

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Authors: Yujie Wei

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Twitter uses a variety of narrative methods (e.g., messages, featured videos, music, and actual events) to strengthen its cultivation effect. Consumers are receiving mass-produced brand stores or images made by brand managers according to strict market specifications. Drawing on the cultivation theory, this quantitative research investigates how following a brand on Twitter for 12 weeks can cultivate their attitude toward the brand and influence their purchase intentions. We conducted three field experiments on Twitter to test the cultivation effects of following a brand for 12 weeks on consumer attitude toward the followed brand. The cultivation effects were measured by comparing the changes in consumer attitudes before and after they have followed a brand over time. The findings of our experiments suggest that when consumers are exposed to a brand’s stable, pervasive, and recurrent tweets on Twitter for 12 weeks, their attitude toward a brand can be significantly changed, which confirms the cultivating effects on consumer attitude. Also, the results indicate that branding activities on Twitter, when properly implemented, can be very effective in changing consumer attitudes toward a brand, increasing the purchase intentions, and increasing their willingness to spread the word-of-mouth for the brand on social media. The cultivation effects are moderated by brand type and consumer age. The research provides three major marketing implications. First, Twitter marketers should create unique content to engage their brand followers to change their brand attitude through steady, cumulative exposure to the branding activities on Twitter. Second, there is a significant moderating effect of brand type on the cultivation effects, so Twitter marketers should align their branding content with the brand type to better meet the needs and wants of consumers for different types of brands. Finally, Twitter marketers should adapt their tweeting strategies according to the media consumption preferences of different age groups of their target markets. This empirical research proves that content is king.

Keywords: tweeting, cultivation theory, consumer brand attitude, purchase intentions, word-of-mouth

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Authors: Ágota Ladó

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Miercurea Ciuc is a town in the historical region of Szeklerland in Transylvania, Romania, with a predominantly Hungarian population (its name in Hungarian being Csíkszereda) having an urban landscape and environment that has been shaped dramatically by different perceptions of urbanization during the history. The town has been part of Hungary and the Austro-Hungarian Empire before the First World War. It even got an important role, becoming in 1876 the seat and administrative center of the historical Csík county. This marks the beginning of the first urbanization process: new administrative buildings, railways, a railway station, a hospital, a Redoute and new schools have been built, new streets have been opened. However, not only the public facilities have changed: the center of the town with its private houses has also transformed, new, modern decorative and lifestyle elements have appeared. One of the streets from the town center, Kossuth street, has been featured on many postcards of the time; even a novel has mentioned it as a symbol of modern urbanization. Right after the First World War, the town became part of Romania and aside from a short interruption (between 1940 and 1944), it is still part of it. The beginning of the second major urbanization process – exactly one hundred years later - is marked by the visit of the communist leader Nicolae Ceaușescu in Miercurea Ciuc on the 6th of October 1976. In the upcoming years, he decided and started to demolish the old Kossuth street and to construct a new avenue with tall blocks of flats according to the principles of socialist urbanization. No other Transylvanian settlement has gone through such systematic abolition of its historical center and urban history during the Communist era. Not only the urban landscape has been affected. The collective memory and contemporary identity of the locals are also violated by this recent transformation of the town: important spaces, buildings, venues of activities and events simply cannot be localized, thus understood - by the younger generations.

Keywords: communist era, historical urban landscape, urban identity, urbanization

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Authors: Scott Draper, Nat Benjanuvatra, Grant Landers, Terry Griffiths, Justin Geldard

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Open water swimming has been an Olympic sport since 2008 and is growing in popularity world-wide as a low impact form of exercise. Unlike pool swimming, open water swimmers experience a range of different environmental conditions, including surface waves, variable water temperature, aquatic life, and ocean currents. This presentation will describe experimental research to investigate how freestyle swimming behaviour and performance is influenced by surface waves. A group of 12 swimmers were instructed to swim freestyle in the 54 m long wave flume located at The University of Western Australia’s Coastal and Offshore Engineering Laboratory. A variety of different regular waves were simulated, varying in height (up to 0.3 m), period (1.25 – 4s), and direction (with or against the swimmer). Swimmer’s velocity and acceleration, respectively, were determined from video recording and inertial sensors attached to five different parts of the swimmer’s body. The results illustrate how the swimmers stroke rate and the wave encounter frequency influence their forward speed and how particular wave conditions can benefit or hinder performance. Comparisons to simplified mathematical models provide insight into several aspects of performance, including: (i) how much faster swimmers can travel when swimming with as opposed to against the waves, and (ii) why swimmers of lesser ability are expected to be affected proportionally more by waves than elite swimmers. These findings have implications across the spectrum from elite to ‘weekend’ swimmers, including how they are coached and their ability to win (or just successfully complete) iconic open water events such as the Rottnest Channel Swim held annually in Western Australia.

Keywords: open water, surface waves, wave height/length, wave flume, stroke rate

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Authors: Melanie Ostermann, Eivind Birkeland, Ying Xue, Alexander Sauter, Mihaela R. Cimpan

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Background: New reliable and robust techniques to assess biological effects of nanomaterials (NMs) in vitro are needed to speed up safety analysis and to identify key physicochemical parameters of NMs, which are responsible for their acute cytotoxicity. The central aim of this study was to validate and evaluate the applicability and reliability of an impedance-based flow cytometry (IFC) technique for the high-throughput screening of NMs. Methods: Eight inorganic NMs from the European Commission Joint Research Centre Repository were used: NM-302 and NM-300k (Ag: 200 nm rods and 16.7 nm spheres, respectively), NM-200 and NM- 203 (SiO₂: 18.3 nm and 24.7 nm amorphous, respectively), NM-100 and NM-101 (TiO₂: 100 nm and 6 nm anatase, respectively), and NM-110 and NM-111 (ZnO: 147 nm and 141 nm, respectively). The aim was to assess the biological effects of these materials on human monoblastoid (U937) cells. Dispersions of NMs were prepared as described in the NANOGENOTOX dispersion protocol and cells were exposed to NMs at relevant concentrations (2, 10, 20, 50, and 100 µg/mL) for 24 hrs. The change in electrical impedance was measured at 0.5, 2, 6, and 12 MHz using the IFC AmphaZ30 (Amphasys AG, Switzerland). A traditional toxicity assay, Trypan Blue Dye Exclusion assay, and dark-field microscopy were used to validate the IFC method. Results: Spherical Ag particles (NM-300K) showed the highest toxic effect on U937 cells followed by ZnO (NM-111 ≥ NM-110) particles. Silica particles were moderate to non-toxic at all used concentrations under these conditions. A higher toxic effect was seen with smaller sized TiO2 particles (NM-101) compared to their larger analogues (NM-100). No interferences between the IFC and the used NMs were seen. Uptake and internalization of NMs were observed after 24 hours exposure, confirming actual NM-cell interactions. Conclusion: Results collected with the IFC demonstrate the applicability of this method for rapid nanotoxicity assessment, which proved to be less prone to nano-related interference issues compared to some traditional toxicity assays. Furthermore, this label-free and novel technique shows good potential for up-scaling in directions of an automated high-throughput screening and for future NM toxicity assessment. This work was supported by the EC FP7 NANoREG (Grant Agreement NMP4-LA-2013-310584), the Research Council of Norway, project NorNANoREG (239199/O70), the EuroNanoMed II 'GEMN' project (246672), and the UH-Nett Vest project.

Keywords: cytotoxicity, high-throughput, impedance, nanomaterials

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Authors: Monika Dmitrzak-Weglarz, Aleksandra Rajewska-Rager, Maria Skibinska, Natalia Lepczynska, Piotr Sibilski, Joanna Pawlak, Pawel Kapelski, Joanna Hauser

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Epidermal growth factor (EGF) is a well-known neurotrophic factor that involves in neuronal growth and synaptic plasticity. The proteomic research provided in order to identify novel candidate biological markers for mood disorders focused on elevated EGF serum level in patients during depression episode. However, the EGF association with mood disorder spectrum among adolescents and young adults has not been studied extensively. In this study, we aim to investigate the serum levels of EGF in adolescents and young adults during hypo/manic, depressive episodes and in remission compared to healthy control group. In our study, we involved 80 patients aged 12-24 years in 2-year follow-up study with a primary diagnosis of mood disorder spectrum, and 35 healthy volunteers matched by age and gender. Diagnoses were established according to DSM-IV-TR criteria using structured clinical interviews: K-SADS for child and adolescents, and SCID for young adults. Clinical and biological evaluations were made at baseline and euthymic mood (at 3th or 6th month of treatment and after 1 and 2 years). The Young Mania Rating Scale and Hamilton Rating Scale for Depression were used for assessment. The study protocols were approved by the relevant ethics committee. Serum protein concentration was determined by Enzyme-Linked Immunosorbent Assays (ELISA) method. Human EGF (cat. no DY 236) DuoSet ELISA kit was used (R&D Systems). Serum EGF levels were analysed with following variables: age, age under 18 and above 18 years old, sex, family history of affective disorders, drug-free vs. medicated. Shapiro-Wilk test was used to test the normality of the data. The homogeneity of variance was calculated with Levene’s test. EGF levels showed non-normal distribution and the homogeneity of variance was violated. Non-parametric tests: Mann-Whitney U test, Kruskall-Wallis ANOVA, Friedman’s ANOVA, Wilcoxon signed rank test, Spearman correlation coefficient was applied in the analyses The statistical significance level was set at p<0.05. Elevated EGF level at baseline (p=0.001) and at month 24 (p=0.02) was detected in study subjects compared with controls. Increased EGF level in women at month 12 (p=0.02) compared to men in study group have been observed. Using Wilcoxon signed rank test differences in EGF levels were detected: decrease from baseline to month 3 (p=0.014) and increase comparing: month 3 vs. 24 (p=0.013); month 6 vs. 12 (p=0.021) and vs. 24 (p=0.008). EGF level at baseline was negatively correlated with depression and mania occurrence at 24 months. EGF level at 24 months was positively correlated with depression and mania occurrence at 12 months. No other correlations of EGF levels with clinical and demographical variables have been detected. The findings of the present study indicate that EGF serum level is significantly elevated in the study group of patients compared to the controls. We also observed fluctuations in EGF levels during two years of disease observation. EGF seems to be useful as an early marker for prediction of diagnosis, course of illness and treatment response in young patients during first episode od mood disorders, which requires further investigation. Grant was founded by National Science Center in Poland no 2011/03/D/NZ5/06146.

Keywords: biological marker, epidermal growth factor, mood disorders, prediction

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Authors: Akpobome Harrison

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Community radio serves as a potent vehicle for amplifying local voices and driving community progress worldwide. It facilitates grassroots communication, empowers residents, and significantly contributes to social, cultural, and economic development. This study investigates the pivotal roles of community radio in elevating local voices and advancing development within Emuoha, Obio-Akpor, and Ikwerre Local Government Areas in Rivers State. Employing a quantitative methodology, the research involved random sampling of respondents via questionnaires. The findings underscore the transformative power of community radio in promoting local voices and fostering development, particularly within Rivers State. Moreover, community radio platforms empower marginalized populations, providing them with a voice and an opportunity to actively participate in the media landscape, share their stories, and express their concerns. This empowerment holds the potential to enhance civic engagement and communal harmony. Community radio stations often prioritize local news, events, and subjects that may not receive adequate coverage in mainstream media, thus facilitating the dissemination of vital community information, including local news, weather updates, and emergency alerts. In light of these observations, this paper advocates for the encouragement of community radio by both the state government and private media entities to facilitate seamless information dissemination. Additionally, the paper highlights the significant role played by the use of Pidgin English as a communication tool, particularly in providing understanding and a voice to marginalized individuals in rural communities.

Keywords: community radio, local voices, marginalized populations, information dissemination, pidgin english, grassroots communication

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Authors: Svetlana Cojocaru, Mircea Petic, Inga Titchiev

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Humanity faces more and more often with different social disasters, which in turn can generate new accidents and catastrophes. To mitigate their consequences, it is important to obtain early possible signals about the events which are or can occur and to prepare the corresponding scenarios that could be applied. Our research is focused on solving two problems in this domain: identifying signals related that an accident occurred or may occur and mitigation of some consequences of disasters. To solve the first problem, methods of selecting and processing texts from global network Internet are developed. Information in Romanian is of special interest for us. In order to obtain the mentioned tools, we should follow several steps, divided into preparatory stage and processing stage. Throughout the first stage, we manually collected over 724 news articles and classified them into 10 categories of social disasters. It constitutes more than 150 thousand words. Using this information, a controlled vocabulary of more than 300 keywords was elaborated, that will help in the process of classification and identification of the texts related to the field of social disasters. To solve the second problem, the formalism of Petri net has been used. We deal with the problem of inhabitants’ evacuation in useful time. The analysis methods such as reachability or coverability tree and invariants technique to determine dynamic properties of the modeled systems will be used. To perform a case study of properties of extended evacuation system by adding time, the analysis modules of PIPE such as Generalized Stochastic Petri Nets (GSPN) Analysis, Simulation, State Space Analysis, and Invariant Analysis have been used. These modules helped us to obtain the average number of persons situated in the rooms and the other quantitative properties and characteristics related to its dynamics.

Keywords: lexicon of disasters, modelling, Petri nets, text annotation, social disasters

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Authors: Khairul Abid Awang

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Happiness and life satisfaction are the vital components in assessing the well-being of the societies and their social progress. These components varies and changes within communities and across time. Thus, due to low level of happiness and life satisfaction, it might affect mental health status psychologically and generally disrupt the health pattern of the individual. Hence, this present study aims to identify the happiness determinants, assessing the happiness and life satisfaction level, as well as examine the relation between happiness among Kampung Jaya Bakti adult community. Quantitative and cross-sectional study with total of 100 observations of 18 years old and above was participated in this study. The study was done in a semi-rural village which is geocentric towards river that branched from South East Asia Sea. Several happiness and life satisfaction instruments was used, inclusive of Individual Determinants of Happiness Scale (IDoHS) that had been developed in this study, in order to identify the determinants of happiness in the area based on the listed determinants. The listed determinants in IDoHS are: i) Daily activities. ii) Adaptation. iii) Goals. iv) Life Events. v) Living condition. vi) Self-confidence. vii) Personality traits. viii) Religion. The results revealed that 98% of the respondents agreed that the listed determinants in IDoHS are statistically significant in determining the happiness. The happiness level revealed that 71 percent (%) of the respondents are ‘very happy’, followed by 26% (‘moderately happy’) and 3% (‘neutral’), while life satisfaction level revealed that 70% of the respondents are ‘very highly satisfied’, followed by 29% (‘highly satisfied’) and 1% (‘moderately satisfied’). Pearson Correlation (Pearson’s r) shows that; happiness determinants listed in IDoHS are affecting happiness level (Pearson’s r: .514, p < 0.01) and life satisfaction level (Pearson’s r: .504, p < 0.01) respectively, as well as happiness that are statistically significant in affecting life satisfaction (Pearson’s r: .653, p < 0.01; Pearson’s r; .546, p < 0.01). It is concluded that the listed determinants in IDoHS are the determinants that affecting happiness and it is also noted that happiness are affecting life satisfaction and vice versa.

Keywords: adult community, determinants, happiness, life satisfaction, subjective well-being

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Authors: Romeu Bonk Mesquita

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Argentina is the South American number 1 country of destiny to intraregional migration flows. This research aims to shed light on the main trends of the Argentine immigrant policy from 2016 on, when Mauricio Marci was elected President, taking the approval of the current and fairly protective of human rights Ley de Migraciones (2003) as an analytical starting point. Foreign Policy Analysis (FPA) serves as the theoretical background, highlighting decision-making processes and institutional designs that encourage or constraint political and social actors. The analysis goes through domestic and international levels, observing how immigration policy is formulated as a public policy and is simultaneously connected to Mercosur and other international organizations, such as the International Organization for Migration (IOM) and the United Nations High Commissioner for Refugees (UNHCR). Thus, the study revolves around the Direccion Nacional de Migraciones, which is the state agency in charge of executing the country’s immigrant policy, as to comprehend how its internal processes and the connections it has with both domestic and international institutions shape Argentina’s immigrant policy formulation and execution. Also, it aims to locate the migration agenda within the country’s contemporary social and political context. The methodology is qualitative, case-based and oriented by process-tracing techniques. Empirical evidence gathered includes official documents and data, media coverage and interviews to key-informants. Recent events, such as the Decreto de Necesidad y Urgencia 70/2017 issued by President Macri, and the return of discursive association between migration and criminality, indicate a trend of nationalization and securitization of the immigration policy in contemporary Argentina.

Keywords: Argentine foreign policy, human rights, immigrant policy, Mercosur

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Authors: Magdalena B. Kaziuk, Waldemar Kosiba

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Background: In the XXI century we have to deal with the epidemic of obesity which is important risk factor for the cardiovascular and kidney diseases. Lipo proteins are directly involved in the atherosclerotic process. Non-high-density lipo protein (non-HDL) began following widespread recognition of its superiority over LDL as a measurement of vascular event risk. Non-HDL includes residual risk which persists in patients after achieved recommended level of LDL. Materials and Methods: The study covered 111 patients (52 females, 59 males, age 51,91±14 years), hospitalized on the intern department. Body composition was assessed using the bioimpendance method and anthropometric measurements. Physical activity data were collected during the interview. The nutritional status and the obesity type were determined with the Waist to Height Ratio and the Waist to Hip Ratio. A function of the kidney was evaluated by calculating the estimated glomerular filtration rate (eGFR) using MDRD formula. Non-HDL was calculated as a difference between concentration of the Total and HDL cholesterol. Results: 10% of patients were found to be underweight; 23.9 % had correct body weight; 15,08 % had overweight, while the remaining group had obesity: 51,02 %. People with the android shape have higher non-HDL cholesterol versus with the gynoid shape (p=0.003). The higher was non-HDL, the lower eGFR had studied subjects (p < 0.001). Significant correlation was found between high non-HDL and incorrect dietary habits in patients avoiding eating vegetables, fruits and having low physical activity (p < 0.005). Conclusions: Android type of figure raises the residual risk of the heart disease associated with higher levels of non-HDL. Increasing physical activity in these patients reduces the level of non-HDL. Non-HDL seems to be the best predictor among all cholesterol measures for the cardiovascular events and worsening eGFR.

Keywords: obesity, non-HDL cholesterol, glomerular filtration rate, lifestyle

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Authors: Javed Mohammed

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Right now, bio-medical infrastructure lags well behind the curve. Our healthcare system is dispersed and disjointed; medical records are a bit of a mess; and we do not yet have the capacity to store and process the crazy amounts of data coming our way from widespread whole-genome sequencing. And then there are privacy issues. Despite these infrastructure challenges, some researchers are plunging into bio medical Big Data now, in hopes of extracting new and actionable knowledge. They are doing delving into molecular-level data to discover bio markers that help classify patients based on their response to existing treatments; and pushing their results out to physicians in novel and creative ways. Computer scientists and bio medical researchers are able to transform data into models and simulations that will enable scientists for the first time to gain a profound under-standing of the deepest biological functions. Solving biological problems may require High-Performance Computing HPC due either to the massive parallel computation required to solve a particular problem or to algorithmic complexity that may range from difficult to intractable. Many problems involve seemingly well-behaved polynomial time algorithms (such as all-to-all comparisons) but have massive computational requirements due to the large data sets that must be analyzed. High-throughput techniques for DNA sequencing and analysis of gene expression have led to exponential growth in the amount of publicly available genomic data. With the increased availability of genomic data traditional database approaches are no longer sufficient for rapidly performing life science queries involving the fusion of data types. Computing systems are now so powerful it is possible for researchers to consider modeling the folding of a protein or even the simulation of an entire human body. This research paper emphasizes the computational biology's growing need for high-performance computing and Big Data. It illustrates this article’s indispensability in meeting the scientific and engineering challenges of the twenty-first century, and how Protein Folding (the structure and function of proteins) and Phylogeny Reconstruction (evolutionary history of a group of genes) can use HPC that provides sufficient capability for evaluating or solving more limited but meaningful instances. This article also indicates solutions to optimization problems, and benefits Big Data and Computational Biology. The article illustrates the Current State-of-the-Art and Future-Generation Biology of HPC Computing with Big Data.

Keywords: high performance, big data, parallel computation, molecular data, computational biology

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Authors: Muhammad A. Ashraf, Scott Steinmetz, Matthew J. Dunn, Assaad R. Masri

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This study focuses on the evolution of soot and soot precursors in three different piloted diffusion turbulent flames. The fuel composition is as follow flame A (ethylene/nitrogen, 2:3 by volume), flame B (ethylene/air, 2:3 by volume), and flame C (pure methane). These flames are stabilized using a 4mm diameter jet surrounded by a pilot annulus with an outer diameter of 15 mm. The pilot issues combustion products from stoichiometric premixed flames of hydrogen, acetylene, and air. In all cases, the jet Reynolds number is 10,000, and air flows in the coflow stream at a velocity of 5 m/s. Time-resolved laser-induced fluorescence (LIF) is collected at two wavelength bands in the visible (445 nm) and UV regions (266 nm) along with laser-induced incandescence (LII). The combined results are employed to study concentration, size, and growth of soot and precursors. A set of four fast photo-multiplier tubes are used to record emission data in temporal domain. A 266nm laser pulse preferentially excites smaller nanoparticles which emit a fluorescence spectrum which is analysed to track the presence, evolution, and destruction of nanoparticles. A 1064nm laser pulse excites sufficiently large soot particles, and the resulting incandescence is collected at 1064nm. At downstream and outer radial locations, intermittency becomes a relevant factor. Therefore, data collected in turbulent flames is conditioned to account for intermittency so that the resulting mean profiles for scattering, fluorescence, and incandescence are shown for the events that contain traces of soot. It is found that in the upstream regions of the ethylene-air and ethylene-nitrogen flames, the presence of soot precursors is rather similar. However, further downstream, soot concentration grows larger in the ethylene-air flames.

Keywords: laser induced incandescence, laser induced fluorescence, soot, nanoparticles

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Authors: Lisete Barlach, Guilherme Ary Plonski

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Innovative ideas are not always synonymous with business opportunities. Any idea can be creative and not recognized as a potential project in which money and time will be invested, among other resources. Even in firms that promote and enhance innovation, there are two 'check-points', the first corresponding to the acknowledgment of the idea as creative and the second, its consideration as a business opportunity. Both the recognition of new business opportunities or new ideas involve cognitive and psychological frameworks which provide individuals with a basis for noticing connections between seemingly independent events or trends as if they were 'connecting the dots'. It also involves prototypes-representing the most typical member of a certain category–functioning as 'templates' for this recognition. There is a general assumption that these kinds of evaluation processes develop through experience, explaining why expertise plays a central role in this process: the more experienced a professional, the easier for him (her) to identify new opportunities in business. But, paradoxically, an increase in expertise can lead to the inflexibility of thought due to automation of procedures. And, besides this, other cognitive biases can also be present, because new ideas or business opportunities generally depend on heuristics, rather than on established algorithms. The paper presents a literature review about the Einstellung effect by tracking famous cases of rejected ideas, extracted from historical records. It also presents the results of empirical research, with data upon rejected ideas gathered from two different environments: projects rejected during first semester of 2017 at a large incubator center in Sao Paulo and ideas proposed by employees that were rejected by a well-known business company, at its Brazilian headquarter. There is an implicit assumption that Einstellung effect tends to be more and more present in contemporaneity, due to time pressure upon decision-making and idea generation process. The analysis discusses desirability, viability, and feasibility as elements that affect decision-making.

Keywords: cognitive biases, Einstellung effect, recognition of business opportunities, rejected ideas

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Authors: Fereshteh M. Haskouei, Habib Alimohammadian

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Magnetic susceptibility (χ) is operational to identify of late quaternary glacial-interglacial cycles in loess-paleosol sequences. It is well accepted that many loess-paleosol sequences bear witness to cold-dry/warm-humid periods, well known as glacial-interglacial cycles, respectively. For this study, loess-paleosol sequence of north-east of Iran was magnetically investigated. The study area is situated at about 8 km away of Neka city, on the main road of Sari-Behshahr, in Mazandaran Province, north of Iran. The youngest deposits of study area are the late Quaternary wind-blown accumulations. In this study, the total number of 117 samples was collected from loess-paleosols units. After that, the natural remnant magnetization (NRM) and magnetic susceptibility (MS) of the samples were measured. Variation of MS of more than 110 loess samples was plotted to reveal the correlation of the MS and paleoclimatic changes. This study aims reconstruction of climatic changes (glacial-interglacial and stadials-interstadials cycles). To confirm our results we compared MS (χ) and the curves of other investigations in paleoclimatology. This correspondence abled us to recognize worldly events in the study area such as: Younger Dryas, the Last Glacial Maximum (LGM), deglaciation of Northern Hemisphere etc. The obtained magnetic data indicate that during almost 50 ka, at least two glacial-interglacial periods occurred in north-east of Iran. Further, variation of χ values revealed short period of climatically cycles known as stadials-interstadials. We recognized 4 stadials and a single stadial as colder sub-periods for S₀ (recently soil-paleosol) and S₂ (lower paleosol), respectively, Moreover, we recognized 6 warmer sub-periods (interstadials) for L₁ (upper loess) and one interstadial L₂ (lower loess).

Keywords: glacial-interglacial cycles, Iran, last glacial maximum (LGM), loess, magnetic susceptibility (χ), Neka, stadials-interstadials sub-periods, younger dryas

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Authors: Huan-Chieh Chiu, Hung-Shuo Wu, Chien-Hao Wang, Yu-Cheng Yang, Ching-Ya Tseng, Joe-Air Jiang

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Power failure resulting from tower collapse due to violent seismic events might bring enormous and inestimable losses. The Chi-Chi earthquake, for example, strongly struck Taiwan and caused huge damage to the power system on September 21, 1999. Nearly 10% of extra high voltage (EHV) transmission towers were damaged in the earthquake. Therefore, seismic hazards of EHV transmission towers should be monitored and evaluated. The ultimate goal of this study is to establish a damage level assessment model for EHV transmission towers. The data of earthquakes provided by Taiwan Central Weather Bureau serve as a reference and then lay the foundation for earthquake simulations and analyses afterward. Some parameters related to the damage level of each point of an EHV tower are simulated and analyzed by the data from monitoring stations once an earthquake occurs. Through the Fourier transform, the seismic wave is then analyzed and transformed into different wave frequencies, and the data would be shown through a response spectrum. With this method, the seismic frequency which damages EHV towers the most is clearly identified. An estimation model is built to determine the damage level caused by a future seismic event. Finally, instead of relying on visual observation done by inspectors, the proposed model can provide a power company with the damage information of a transmission tower. Using the model, manpower required by visual observation can be reduced, and the accuracy of the damage level estimation can be substantially improved. Such a model is greatly useful for health and construction monitoring because of the advantages of long-term evaluation of structural characteristics and long-term damage detection.

Keywords: damage level monitoring, drift ratio, fragility curve, smart grid, transmission tower

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Authors: B. Niez, B. Moulia, J. Dlouha, E. Badel

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Trees adjust their development to the environmental conditions they experience. Storms events of last decades showed that acclimation of trees to mechanical stresses due to wind is a very important process that allows the trees to sustain for long years. In the future, trees will experience new wind patterns, namely, more often strong winds and fewer daily moderate winds. Moreover, these patterns will go along with drought periods that may interact with the capacity of trees to adjust their growth to mechanical stresses due to wind. It is necessary to understand the mechanisms of wood functional acclimations to environmental conditions in order to predict their behaviour and in order to give foresters and breeders the relevant tools to adapt their forest management. This work aims to study how trees adjust the mechanical and hydraulic functions of their wood to environmental stresses and how this acclimation may be beneficial for the tree to resist to future stresses. In this work, young poplars were grown under controlled climatic conditions that include permanent environmental stress (daily mechanical stress of the stem by bending and/or hydric stress). Then, the properties of wood formed under these stressed conditions were characterized. First, hydraulic conductivity and sensibility to cavitation were measured at the tissue level in order to evaluate the changes in water transport capacity. Secondly, bending tests and Charpy impact tests were carried out at the millimetric scale to locally measure mechanical parameters such as elastic modulus, elastic limit or rupture energy. These experimental data allow evaluating the impacts of mechanical and water stress on the wood material. At the stem level, they will be merged in an integrative model in order to evaluate the beneficial aspect of wood acclimation for trees.

Keywords: acclimation, environmental stresses, hydraulics, mechanics, wood

Procedia PDF Downloads 192