Search results for: sky exposure plane

Authors: Sonia Mannan

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A qualitative study was conducted in a rural area of the southwestern region of Bangladesh to identify perceptions, practices, and the role of first-time mothers surrounding acute respiratory infections (ARI) in infants and children aged under four years. The study reveals that all mothers had knowledge of ARI and were able to identify a number of signs and symptoms. They also recognized pneumonia and thought it to be caused by exposure to cold or weather change, supernatural causes, evil influences, mothers’ negligence, and failure to observe ‘purdah’. They were able to identify chest retractions, difficult breathing, and inability to feed as signs of severe disease needing treatment outside the home. In these cases, spiritual healers were sought, and allopathic treatment was delayed or avoided. Home care practices involved massaging the child with oil and avoiding 'cooling' foods, including water. With the presence of fever and breathing difficulty, mothers tended to increase the number and diversity of medicines, although more concern was expressed about fever than about breathing difficulty. Effective medical care was more likely to be delayed for infants than for older children (they often waited 2-5 days after signs of illness appeared); infants were also more likely to be taken to a spiritual healer as the first-choice provider. The reasons for these perceptions and practices and their implications on the ARI of infants and young children are discussed. Community intervention is identified as viable, effective, and practical to address the body of local socio-cultural knowledge about family practices and the role of the mother regarding the mitigation of ARI in infants and young children.

Keywords: acute respiratory infections , public health, pneumonia, Bangladesh

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Authors: Priyanka Kumari Gupta, Punya Prasanna Paltani, Shrivishal Tripathi

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This paper proposes a nonlinear photonic crystal ring resonator-based all-optical 2 × 2 switch. The nonlinear Kerr effect is used to evaluate the essential 2 x 2 components of the photonic crystal-based optical switch, including the bar and cross states. The photonic crystal comprises a two-dimensional square lattice of dielectric rods in an air background. In the background air, two different dielectric materials are used for this comparison study separately. Initially with chalcogenide glass rods, then with GaAs rods. For both materials, the operating wavelength, bandgap diagram, operating power intensities, and performance parameters, such as the extinction ratio, insertion loss, and cross-talk of an optical switch, have also been estimated using the plane wave expansion and the finite-difference time-domain method. The chalcogenide glass material (Ag20As32Se48) has a high refractive index of 3.1 which is highly suitable for switching operations. This dielectric material is immersed in an air background with a nonlinear Kerr coefficient of 9.1 x 10-17 m2/W. The resonance wavelength is at 1552 nm, with the operating power intensities at the cross-state and bar state around 60 W/μm2 and 690 W/μm2. The extinction ratio, insertion loss, and cross-talk value for the chalcogenide glass at the cross-state are 17.19 dB, 0.051 dB, and -17.14 dB, and the bar state, the values are 11.32 dB, 0.025 dB, and -11.35 dB respectively. The gallium arsenide (GaAs) dielectric material has a high refractive index of 3.4, a direct bandgap semiconductor material highly preferred nowadays for switching operations. This dielectric material is immersed in an air background with a nonlinear Kerr coefficient of 3.1 x 10-16 m2/W. The resonance wavelength is at 1558 nm, with the operating power intensities at the cross-state and bar state around 110 W/μm2 and 200 W/μm2. The extinction ratio, insertion loss, and cross-talk value for the chalcogenide glass at the cross-state are found to be 3.36.19 dB, 2.436 dB, and -5.8 dB, and for the bar state, the values are 15.60 dB, 0.985 dB, and -16.59 dB respectively. This paper proposes an all-optical 2 × 2 switch based on a nonlinear photonic crystal using a ring resonator. The two-dimensional photonic crystal comprises a square lattice of dielectric rods in an air background. The resonance wavelength is in the range of photonic bandgap. Later, another widely used material, GaAs, is also considered, and its performance is compared with the chalcogenide glass. Our presented structure can be potentially applicable in optical integration circuits and information processing.

Keywords: photonic crystal, FDTD, ring resonator, optical switch

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Authors: Doufoungognon Carine Kone

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Heavy metals present in large quantities in ecosystems can alter biological and cellular functions and disrupt trophic functions. However, their toxicity can change according to thermal conditions, as toxicity depends on their bioavailability and thermal optimum of organisms. Organisms can develop different tolerance strategies to maintain themselves in a stressful environment, but these strategies are often studied in a single-stressor context. This study evaluates the responses of the ciliate Tetrahymena thermophila to copper, high temperature, and their interaction. Six genotypes were exposed to a gradient of copper concentrations ranging from 0 to 350mg/L in synthetic media at three temperatures: 15°C, 23°C, and 31°C. Cell density, cell shape and size (and their variance), swimming speed and trajectory, and copper uptake rate were measured. Depending on the genotype, swimming speed, trajectory, and cell size were highly affected by stress gradients. One gets bigger, while two genotypes get smaller and the other remain unchanged. Some genotypes swam less rapidly, while others speed up as copper and temperature increased. Concerning copper uptake, the two genotypes accumulating the best and the worst, whatever the copper concentration or temperature, were also those that had the highest densities. Finally, very few temperature x copper interactions were observed on phenotypic parameters. The diversity of phenotypic responses revealed in this study reflects the existence of divergent strategies adopted by Tetrahymena thermophila to resist to copper and thermal stress, which suggests an important role of intraspecific variability in biodiversity response to environmental stress. One general and the surprising pattern was a global absence of interactive effects between copper and high temperature exposure on the observed phenotypic responses.

Keywords: ciliate, copper, intraspecific variability, phenotype, temperature, tolerance, multiple stressors

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Authors: Maryam Ghavam Sadri, Maryam Shahrooz

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Background: Nowadays the prevalence of metabolic syndrome (Mets) has taken on a growing trend. Studies have shown the relationship between vitamin D deficiency (VDD) status and Mets in children. Also studies have recorded that exerting strategies for vitamin D status improvement can help prevent Mets in children. This study investigated multiple strategies of prevention of Mets resulting from VDD in children. Methods: This review study has been done by using keywords related to the topic and 54 articles were found (2000-2015) that 25 were selected according to the indicators of Mets, supplementation and fortification of foods with vitamin D and attention to children environment and life style. Results: Studies have suggested the correlation between serum levels of vitamin D with waist circumference (p < 0.0001), systolic blood pressure (p=0.01), HOMA-IR (p=0.001) and HDL cholesterol (p < 0.0001). An inverse correlation between serum 25 (OH) D and HOMA-IR (p = 0.006) and insulin (P = 0.002) has been proved in overweight group. Higher HOMASDS and triglycerides found in vitamin D deficient obese children compared to control group without VDD (p=0.04). After supplementation with vitamin D, serum TG concentration decreases significantly (p=0.04), and improves insulin resistance (p=0.02). The prevalence of VDD is associated with time of watching TV (P < 0.01), hours of physical activity per week (P = 0.01), skipping breakfast (P < 0.001) soda intake (P < 0.001), and milk intake per day (P < 0.01). Conclusion: According to the beneficial role of vitamin D in prevention of Mets and proven relationship between serum levels of vitamin D and Mets indicators, we can prevent childhood Mets through the application of appropriate strategies such as supplementation and food fortification with vitamin D and positive changes in children life style with especial attention to physical activity in exposure of sunlight and their environment condition.

Keywords: children, metabolic syndrome, prevention strategies, vitamin D

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Authors: M. E. Joret, F. Germeys, P. Van de Craen

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Background: Previous studies have shown that ‘full’ bilingualism seems to enhance the executive functions in children, young adults and elderly people. Executive functions refer to a complex cognitive system responsible for self-controlled and planned behavior and seem to predict academic achievement. The present study aimed at investigating whether similar effects could be found in children learning their second language at school in immersion education programs. Methods: In this study, 44 children involved in immersion education for 4 to 5 years were compared to 48 children in traditional schools. All children were between 9 and 11 years old. To assess executive functions, the Simon task was used, a neuropsychological measure assessing executive functions with reaction times and accuracy on congruent and incongruent trials. To control for background measures, all children underwent the Raven’s coloured progressive matrices, to measure non-verbal intelligence and the Echelle de Vocabulaire en Images Peabody (EVIP), assessing verbal intelligence. In addition, a questionnaire was given to the parents to control for other confounding variables, such as socio-economic status (SES), home language, developmental disorders, etc. Results: There were no differences between groups concerning non-verbal intelligence and verbal intelligence. Furthermore, the immersion learners showed overall faster reaction times on both congruent and incongruent trials compared to the traditional learners, but only after 5 years of training, not before. Conclusion: These results show that the cognitive benefits found in ‘full’ bilinguals also appear in children involved in immersion education, but only after a sufficient exposure to the second language. Our results suggest that the amount of second language training needs to be sufficient before these cognitive effects may emerge.

Keywords: bilingualism, executive functions, immersion education, Simon task

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Authors: Shakila Singh

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Dominant discourses constitute heterosexuality as natural, normal and the only legitimate sexuality, and diverse sexual subjectivities as abnormal, unnatural and socially taboo. Similarly, the cisgender subject is reified. There are ongoing debates about the inclusion and suitability of sexuality education in the school curriculum and research show that teachers are not adequately prepared to teach about such issues in the classroom. Not surprising then, that many young people enter these institutions having had limited previous exposure to, or education about, sex, gender and sexuality diversity. This paper discusses the presence of heterosexism and cissexism at multiple layers in higher education institutions, impacting students and staff. Increasing knowledge and awareness of sex, gender and sexuality diversities is also crucial to challenging existing perceptions of sex, gender and sexuality diversities that marginalise and subordinate a large proportion of students and staff. There is a persistent disjuncture between dominant discourses that generally position higher education institutions as socially progressive, open environments and the discourses that legitimate the ascendency of heterosexual and cisgender identities. This paper argues that such disjuncture must be addressed by providing inclusive physical and emotional spaces if universities are to affirm every individual and produce graduates across all disciplines with the cultural capability to engage with increasingly diverse communities. Given the key role of language in shaping cultural and social attitudes, using gender-inclusive language is a powerful way to promote gender equality and eradicate gender bias. This means speaking and writing in a way that does not discriminate against a particular sex, gender or sexual identity and does not perpetuate gender stereotypes. Individuals must be allowed to present themselves and identify in ways they choose and be addressed by their chosen pronouns.

Keywords: heteronormativity, inclusivity, gender, universities

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Authors: Tri Wisudawati, Radita Dwi Putera

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The role of human resources is the basic capital in determining the purpose of a business place. Without the role of human resources, activities in the company will not run smoothly. Every business place always has a risk of accidents. The magnitude of the risk that occurs depends on the type of industry, technology, and risk control efforts made. Work-related accidents are accidents that occur due to work or while carrying out work. Welding MSMEs have a fairly high risk to health, safety and the environment both from the side of workers who can cause accidents and from the side of the work environment, which has the potential to become a hazard and risk. Participatory ergonomic intervention can be a feasible and effective approach to reducing exposure to work-related risk factors in developing country industries. Complaints about occupational health and safety experienced by workers in the welding workshop industry should be able to be overcome by implementing an ergonomic intervention approach. The analysis process includes HIRARC analysis, participatory ergonomics analysis, and SEM-PLS analysis. Hierarch analysis is carried out by assessing the level of severity and likelihood, as well as risk control. At the participatory ergonomics analysis stage, it is obtained from the organizational culture and organizational stakeholders. At the SEM-PLS stage, an analysis is carried out to see whether there is a strong relationship between the research variables in order to produce occupational health and safety (K3) and worker productivity in the welding shop better and in accordance with welding safety standards. So that the output of this study is how participatory ergonomics interventions affect working conditions to improve occupational health and safety and the productivity of welding workers.

Keywords: ergonomic partisipatory, health and safety, welding workers, welding safety

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Authors: Hyeon-Kyo Lim, Hyunjung Kim, Kune-Woo Lee

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Decommissioning process of nuclear facilities can be said to consist of a sequence of problem solving activities, partly because there may exist working environments contaminated by radiological exposure, and partly because there may also exist industrial hazards such as fire, explosions, toxic materials, and electrical and physical hazards. As for an individual hazard factor, risk assessment techniques are getting known to industrial workers with advance of safety technology, but the way how to integrate those results is not. Furthermore, there are few workers who experienced decommissioning operations a lot in the past. Therefore, not a few countries in the world have been trying to develop appropriate counter techniques in order to guarantee safety and efficiency of the process. In spite of that, there still exists neither domestic nor international standard since nuclear facilities are too diverse and unique. In the consequence, it is quite inevitable to imagine and assess the whole risk in the situation anticipated one by one. This paper aimed to find out an appropriate technique to integrate individual risk assessment results from the viewpoint of experts. Thus, on one hand the whole risk assessment activity for decommissioning operations was modeled as a sequence of individual risk assessment steps, and on the other, a hierarchical risk structure was developed. Then, risk assessment procedure that can elicit individual hazard factors one by one were introduced with reference to the standard operation procedure (SOP) and hierarchical task analysis (HTA). With an assumption of quantification and normalization of individual risks, a technique to estimate relative weight factors was tried by using the conventional Analytic Hierarchical Process (AHP) and its result was reviewed with reference to judgment of experts. Besides, taking the ambiguity of human judgment into consideration, debates based upon fuzzy inference was added with a mathematical case study.

Keywords: decommissioning, risk assessment, analytic hierarchical process (AHP), fuzzy inference

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Authors: Selen Unaldi, Emmanuel Richaud, Matthieu Gervais, Laurent Berthe

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Aircrafts are painted with several layers to guarantee their protection from external attacks. For aluminum AA 2024-T3 (metallic structural part of the plane), a protective primer is applied to ensure its corrosion protection. On top of this layer, the top coat is applied for aesthetic aspects. During the lifetime of an aircraft, top coat stripping has an essential role which should be operated as an average of every four years. However, since conventional stripping processes create hazardous disposals and need long hours of labor work, alternative methods have been investigated. Amongst them, laser stripping appears as one of the most promising techniques not only because of the reasons mentioned above but also its controllable and monitorable aspects. The application of a laser beam from the coated side provides stripping, but the depth of the process should be well controlled in order to prevent damage to a substrate and the anticorrosion primer. Apart from that, thermal effects should be taken into account on the painted layers. As an alternative, we worked on developing a process that includes the usage of shock wave propagation to create the stripping via mechanical effects with the application of the beam from the substrate side (back face) of the samples. Laser stripping was applied on thickness-specified samples with a thickness deviation of 10-20%. First, the stripping threshold is determined as a function of power density which is the first flight off of the top coats. After obtaining threshold values, the same power densities were applied to specimens to create large stripping zones with a spot overlap of 10-40%. Layer characteristics were determined on specimens in terms of physicochemical properties and thickness range both before and after laser stripping in order to validate the substrate material health and coating properties. The substrate health is monitored by measuring the roughness of the laser-impacted zones and free surface energy tests (both before and after laser stripping). Also, Hugoniot Elastic Limit (HEL) is determined from VISAR diagnostic on AA 2024-T3 substrates (for the back face surface deformations). In addition, the coating properties are investigated as a function of adhesion levels and anticorrosion properties (neutral salt spray test). The influence of polyurethane top-coat thickness is studied in order to verify the laser stripping process window for industrial aircraft applications.

Keywords: aircraft coatings, laser stripping, laser adhesion tests, epoxy, polyurethane

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Authors: Fadwa Chtioui

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Vital Pulp Therapy (VPT) is nowadays challenging the deep-rooted dogma of root canal treatment, being the only therapeutic option for permanent teeth diagnosed with irreversible pulpitis or carious pulp exposure. Histologic and clinical research has shown that compromised dental pulp can be treated without the full removal or excavation of all healthy pulp, and the outcome of the partial or full pulpotomy followed by a Tricalcium-Silicate-based dressing seems to show promising results in maintaining pulp vitality and preserving affected teeth in the long term. By reviewing recent advances in the techniques of VPT and their clinical effectiveness and safety in permanent teeth with irreversible Pulpitis, this work provides a new understanding of pulp pathophysiology and defense mechanisms and will reform dental practitioners' decision-making in treating irreversible pulpits from root canal therapy to vital pulp therapy by taking advantage of the biological effects of Tricalcium Silicate materials. Biography of presenting author: Fadwa Chitoui graduated from the school of Dental Medicine of Monastir, Tunisia, in 2015. After getting her DDS degree with honors, she earned her Postgraduate master's Degree in Endodontics and Restorative Dentistry from her Faculty. Since 2021, she has Started her own private and specialized practice based in the capital Tunis. She enjoys the sphere of associative life, worked with national and international associations, and got engaged in scientific dental research, whereby she tailored her passion for her field of specialty towards broadening her knowledge and ambitions, holding conferences and workshops nationally and internationally and publishing scientific articles in several journals.

Keywords: irreversible pulpitis, permanenet teeth, vital pulp therapy, pulpotomy

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Authors: Renan De Caldas Honorato, Ana Augusta Ferreira De Freitas

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Homosexuality is still criminalized in a large number of countries. In some of them, being gay or lesbian can even be punished by death. Added to this context, the experiences of social discrimination faced by the LGBT population, including homophobia, machismo and misogyny, cause numerous restrictions throughout their lives. The possibility of confronting these challenges in moments that should be pleasant, such as on a trip or on vacation, is unpleasant, to say the least. In the current scenario of intensifying the use of Social network sites (SNSs) to search for information, including in the tourist area, this work aims to analyze the sharing of tourist experiences with situations of confrontation and perceptions of homophobia, machismo and misogyny, and restrictions suffered in tourist destinations. The fieldwork is a community of LGBT backpackers based on Facebook. Netnography was the core method adopted. A qualitative approach was conducted and 463 publications posted from January to December 2020 were assessed through the computer-mediated discourse analysis (CMDA). The results suggest that these publications exist to identify the potential exposure to these offensive behaviors while traveling. Individuals affirm that the laws, positive or not, in relation to the LGBT public are not the only factors for a place to be defined as safe or not for gay travelers. The social situation of a country and its laws are quite different and this is the main target of these publications. The perception of others about the chosen destination is more important than knowing your rights and the legal status of each country and it also lessens uncertainty, even when they are never totally confident when choosing a travel destination. In certain circumstances, sexual orientation also needs to be protected from the judgment of hosts and residents. The systemic treatment of homophobic behavior and the construction of a more inclusive society are urgent.

Keywords: homophobia, hospitality, machismo, misogyny

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Authors: Fangyuan Shao, Wei Liu, Deli Gao

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With the increasing speed of oil and gas exploration, development and production at home and abroad, the demand for drilling speed up technology is becoming more and more critical to reduce the development cost. Highly efficient and personalized PDC bit is important equipment in the bottom hole assembly (BHA). Therefore, improving the rock-breaking efficiency of PDC bits will help reduce drilling time and drilling cost. Advances in PDC bit technology have resulted in a leapfrogging improvement in the rate of penetration (ROP) of PDC bits over roller cone bits in soft to medium-hard formations. Recently, with the development of PDC technology, the diameter of the PDC tooth can be further expanded. The maximum diameter of the PDC cutter used in this paper is 22 mm. According to the theoretical calculation, under the same depth of cut (DOC), the 22mm-PDC cutter increases the exposure of the cutter, and the increase of PDC cutter diameter helps to increase the cutting area of the PDC cutter. In order to evaluate the cutting performance of the 22 mm-PDC cutter and the existing commonly used cutters, the 16 mm, 19 mm and 22 mm PDC cutter was selected put on a vertical turret lathe (VTL) in the laboratory for cutting tests under different DOCs. The DOCs were 0.5mm, 1.0 mm, 1.5 mm and 2.0 mm, 2.5 mm and 3 mm, respectively. The rock sample used in the experiment was limestone. Results of laboratory tests have shown the new 22 mm-PDC cutter technology greatly improved cutting efficiency. On the one hand, as the DOC increases, the mechanical specific energy (MSE) of all cutters decreases, which means that the cutting efficiency increases. On the other hand, under the same DOC condition, the larger the cutter diameter is, the larger the working area of the cutter is, which leads to higher the cutting efficiency. In view of the high performance of the 22 mm-PDC cutters, which was applied to carry out full-scale bit field experiments. The result shows that the bit with 22mm-PDC cutters achieves a breakthrough improvement of ROP than that with conventional 16mm and 19mm cutters in offset well drilling.

Keywords: polycrystalline diamond compact, 22 mm-PDC cutters, cutting efficiency, mechanical specific energy

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Authors: Ragy Raafat Gaber Attaalla

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For cardiovascular illness, oral P2Y12 inhibitors including clopidogrel, prasugrel, and ticagrelor are frequently recommended. Each of these medications has advantages and disadvantages. In the absence of genotyping, it has been demonstrated that the stronger platelet aggregation inhibitors prasugrel and ticagrelor are superior than clopidogrel at preventing significant adverse cardiovascular events following an acute coronary syndrome and percutaneous coronary intervention (PCI). Both, nevertheless, come with a higher risk of bleeding unrelated to a coronary artery bypass. As a prodrug, clopidogrel needs to be bioactivated, principally by the CYP2C19 enzyme. A CYP2C19 no function allele and diminished or absent CYP2C19 enzyme activity are present in about 30% of people. The reduced exposure to the active metabolite of clopidogrel and reduced inhibition of platelet aggregation among clopidogrel-treated carriers of a CYP2C19 no function allele likely contributed to the reduced efficacy of clopidogrel in clinical trials. Clopidogrel's pharmacogenetic results are strongest when used in conjunction with PCI, but evidence for other indications is growing. One of the most typical examples of clinical pharmacogenetic application is CYP2C19 genotype-guided antiplatelet medication following PCI. Guidance is available from expert consensus groups and regulatory bodies to assist with incorporating genetic information into P2Y12 inhibitor prescribing decisions. Here, we examine the data supporting genotype-guided P2Y12 inhibitor selection's effects on clopidogrel response and outcomes and discuss tips for pharmacogenetic implementation. We also discuss procedures for using genotype data to choose P2Y12 inhibitor therapies as well as any unmet research needs. Finally, choosing a P2Y12 inhibitor medication that optimally balances the atherothrombotic and bleeding risks may be influenced by both clinical and genetic factors.

Keywords: inhibitors, cardiovascular events, coronary intervention, pharmacogenetic implementation

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Authors: Sudeshna Mukherjee, Leena Fageria, R. Venkataramana Dilip, Rajdeep Chowdhury, Jitendra Panwar

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Metal nanoparticles in recent years have gained importance in cancer therapy due to their enhanced permeability retention effect. Among various nanomaterials, silver nanoparticles (AgNPs) have received considerable attention due to their unique properties like conductivity, chemical stability, relative lower toxicity and outstanding therapeutic potential, such as anti-inflammatory, antimicrobial and anti-cancerous activities. In this study, we took a greener approach to synthesize silver nanoparticle from fungus and analyze its effects on both epithelial and mesenchymal derived cancer cells. Much research has been done on nanoparticle-induced apoptosis, but little is known about its role in autophagy. In our study, the silver nanoparticles were seen to induce autophagy which was analyzed by studying the expression of several autophagy markers like, LC3B-II and ATG genes. Monodansylcadaverine (MDC) assay also revealed the induction of autophagy upon treatment with AgNPs. Inhibition of autophagy by chloroquine resulted in increased cell death suggesting autophagy as a survival strategy adopted by the cells. In parallel to autophagy induction, silver nanoparticles induced ROS accumulation. Interestingly, autophagy inhibition by chloroquine increased ROS level, resulting in enhanced cell death. We further analyzed MAPK signaling upon AgNP treatment. It was observed that along with autophagy, activation of JNK signaling served as pro-survival while ERK signaling served as a pro-death signal. Our results provide valuable insights into the role of autophagy upon AgNP exposure and provide cues to probabilistic strategies to effectively sensitize cancer cells.

Keywords: autophagy, JNK signalling, reactive oxygen species, silver nanoparticles

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Authors: Samuel Kwaku Essien, Catherine Trask, Niels Koehncke, Brenna Bath

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Background: Low back disorder (LBD) is the most common musculoskeletal problem among farmers, with higher prevalence than other occupations. Operators of tractors and other farm machinery such as combines or all-terrain vehicles (ATV) can have considerable cumulative exposure to whole body vibration (WBV). Although there appears to be an association between LBD and WBV, lack of prospective studies makes the relationship between LBD and WBV unclear. Purpose: This study investigates the association between WBV and LBD among Saskatchewan farmers using a prospective cohort study Methods: The Saskatchewan Farm Injury Cohort Study Phase I (2007) and II (2013) data were used. Baseline data were collected via postal questionnaire on accumulated yearly tractor, combine, and ATV use as well as several covariates to support a biopsychosocial model of LBD. Follow-up data on musculoskeletal symptoms were collected for the 6-year with sample size of 1149. Questions on ‘low back trouble’ (ache, pain, discomfort) experienced in the last 12 months answered by farmer participants as ‘yes’ or ‘no’. A GEE-modified Poisson approach was performed using SPSS 22 and SAS 9.4. Results: Twelve-month Prevalence of LBD was 59.8%. In multivariate analysis of the 6-year follow-up, LBD was associated with ATV operation and tractor operation, with a dose-response relationship for annual accumulated tractor operation. Although combine operation ≥ 61 hrs/year was related to LBD in bivariate analysis, this difference did not persist after adjustment for confounder. Age was found to be a confounder in relationship between WBV and LBD and no interactions were found. Conclusion: Longer annual tractor operation and older age are important predictors of LBD symptoms in farmers. Future research involving direct measurement can help identify appropriate prevention strategies.

Keywords: agriculture, low back disorder, low back pain, occupational health

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Authors: Amir Ali, Laura Yael Mendoza

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The application of nanomaterials is becoming the most effective strategy of elicitation to produce a desirable level of plant biomass with complex medicinal compounds. This study was designed to check the influence of phytosynthesized iron nanoparticles (FeNPs) on physical growth characteristics, antioxidant status, and production of steviol glycosides of in vitro grown Stevia rebaudiana. Effect of different concentrations of iron nanoparticles replacement of iron sulfate in MS medium (stock solution) on invitro stevia plant growth following positive control (MS basal medium), negative control (iron sulfate devoid medium), iron sulfate devoid MS medium and supplemented with FeNPs at different concentrations (5.6 mg/L, 11.2 mg/L, 16.8 mg/L, 22.4 mg/L) was evaluated. The iron deficiency leads to a drastic reduction in plant growth. In contrast, applying FeNPs leads to improvement in plant height, leave diameter, improved leave morphology, etc., in a concentration-dependent manner. Furthermore, the stress caused by FeNPs at 16.8 mg/L in cultures produced higher levels of total phenolic content (3.7 ± 0.042 mg/g dry weight: DW) and total flavonoid content (1.9 ± 0.022 mg/g DW and antioxidant activity (78 ± 4.6%). In addition, plants grown in the presence of FeNPs at 22.4 mg/L resulted in higher enzymatic antioxidant activities (SOD = 3.5 ± 0.042 U/mg; POD = 2.6 ± 0.026 U/mg; CAT = 2.8 ± 0.034 U/mg and APx = 3.6 ± 0.043 U/ mg), respectively. Furthermore, exposure to a higher dose of FeNPs (22.4 mg/L) exhibited the maximum amount of stevioside (stevioside: 4.6 ± 0.058 mg/g (DW) and rebaudioside A: 4.9 ± 0.068 mg/g DW) as compared to other doses. The current investigation confirms the effectiveness of FeNPs in growth media. It offers a suitable prospect for commercially desirable production of S. rebaudiana biomass with higher sweet glycosides profiles in vitro.

Keywords: cell culture, stevia, iron nanoparticles, antioxidants

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Authors: Sharmin Ferdewsi Rakhi, A. H. M. Mohsinul Reza, Brynley Davies, Jianzhong Wang, Youhong Tang, Jian Qin

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Mass production of microalgae has become a focus of research owing to their promising aspects for sustainable food, biofunctional compounds, and biofuel feedstock. However, low lipid content with optimum algal biomass is still a challenge that must be resolved for commercial use. This research aims to determine the effects of light spectral shift and reactive oxygen species (ROS) on growth and lipid biosynthesis in a green microalga, Chlamydomonas reinhardtii. Aggregation Induced Emission (AIE)-based photosensitisers, CN-TPAQ-PF6 ([C₃₂H₂₃N₄]+) with high ROS productivity, was introduced into the algal culture media separately for effective conversion of the green-yellow-light to the red spectra. The intense photon energy and high-photon flux density in the photosystems and ROS supplementation induced photosynthesis and lipid biogenesis. In comparison to the control, maximum algal growth (0.15 g/l) was achieved at 2 µM CN-TPAQ-PF6 exposure. A significant increase in total lipid accumulation (146.87 mg/g dry biomass) with high proportion of 10-Heptadecanoic acid (C17:1) linolenic acid (C18:2), α-linolenic acid (C18:3) was observed. The elevated level of cellular NADP/NADPH triggered the Acetyl-Co-A production in lipid biogenesis cascade. Furthermore, MTT analysis suggested that this nanomaterial is highly biocompatible on HaCat cell lines with 100% cell viability. This study reveals that the AIE-based approach can strongly impact algal biofactory development for sustainable food, healthy lipids and eco-friendly biofuel.

Keywords: microalgae, photosensitiser, lipid, biomass, aggregation-induced-emission, reactive oxygen species

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Authors: Khodzhaberdi Allaberdiev

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Aromaticity, one of the most important concepts in organic chemistry, has attracted considerable interest from both experimentalists and theoreticians. The geometry optimization of p-substituted o-(N-dialkyl)aminomethylphenols, o-DEAMPH XC₆ H₅CH ₂Y (X=p-OCH₃, CH₃, H, F, Cl, Br, COCH₃, COOCH₃, CHO, CN and NO₂, Y=o-N (C₂H₅)₂, o-DEAMPHs have been performed in the gas phase using the B3LYP/6-311+G(d,p) level. Aromaticities of the considered molecules were investigated using different indices included geometrical (HOMA and Bird), electronic (FLU, PDI and SA) magnetic (NICS(0), NICS(1) and NICS(1)zz indices. The linear dependencies were obtained between some aromaticity indices. The best correlation is observed between the Bird and PDI indices (R² =0.9240). However, not all types of indices or even different indices within the same type correlate well among each other. Surprisingly, for studied molecules in which geometrical and electronic cannot correctly give the aromaticity of ring, the magnetism based index successfully predicts the aromaticity of systems. 1H NMR spectra of compounds were obtained at B3LYP/6–311+G(d,p) level using the GIAO method. Excellent linear correlation (R²= 0.9996) between values the chemical shift of hydrogen atom obtained experimentally of 1H NMR and calculated using B3LYP/6–311+G(d,p) demonstrates a good assignment of the experimental values chemical shift to the calculated structures of o-DEAMPH. It is found that the best linear correlation with the Hammett substituent constants is observed for the NICS(1)zz index in comparison with the other indices: NICS(1)zz =-21.5552+1,1070 σp- (R²=0.9394). The presence intramolecular hydrogen bond in the studied molecules also revealed changes the aromatic character of substituted o-DEAMPHs. The HOMA index predicted for R=NO2 the reduction in the π-electron delocalization of 3.4% was about double that observed for p-nitrophenol. The influence intramolecular H-bonding on aromaticity of benzene ring in the ground state (S0) are described by equations between NICS(1)zz and H-bond energies: experimental, Eₑₓₚ, predicted IR spectroscopical, Eν and topological, EQTAIM with correlation coefficients R² =0.9666, R² =0.9028 and R² =0.8864, respectively. The NICS(1)zz index also correlates with usual descriptors of the hydrogen bond, while the other indices do not give any meaningful results. The influence of the intramolecular H-bonding formation on the aromaticity of some substituted o-DEAMPHs is criteria to consider the multidimensional character of aromaticity. The linear relationships as well as revealed between NICS(1)zz and both pyramidality nitrogen atom, ΣN(C₂H₅)₂ and dihedral angle, φ CAr – CAr -CCH₂ –N, to characterizing out-of-plane properties.These results demonstrated the nonplanar structure of o-DEAMPHs. Finally, when considering dependencies of NICS(1)zz, were excluded data for R=H, because the NICS(1) and NICS(1)zz values are the most negative for unsubstituted DEAMPH, indicating its highest aromaticity; that was not the case for NICS(0) index.

Keywords: aminomethylphenols, DFT, aromaticity, correlations

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Authors: Emily Rabe, Stephanie Candelaria, Rachel Malone, Olivia Lenz, Greg Newbloom

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Electrodialysis (ED) is a well-developed technology for ion removal in a variety of applications. However, many industries generate harsh wastewater streams that are incompatible with traditional ion exchange membranes. Membrion® has developed novel ceramic-based ion exchange membranes (IEMs) offering several advantages over traditional polymer membranes: high performance in low pH, chemical resistance to oxidizers, and a rigid structure that minimizes swelling. These membranes are synthesized with our patented silane-based sol-gel techniques. The pore size, shape, and network structure are engineered through a molecular self-assembly process where thermodynamic driving forces are used to direct where and how pores form. Either cationic or anionic groups can be added within the membrane nanopore structure to create cation- and anion-exchange membranes. The ceramic IEMs are produced on a roll-to-roll manufacturing line with low-temperature processing. Membrane performance testing is conducted using in-house permselectivity, area-specific resistance, and ED stack testing setups. Ceramic-based IEMs show comparable performance to traditional IEMs and offer some unique advantages. Long exposure to highly acidic solutions has a negligible impact on ED performance. Additionally, we have observed stable performance in the presence of strong oxidizing agents such as hydrogen peroxide. This stability is expected, as the ceramic backbone of these materials is already in a fully oxidized state. This data suggests ceramic membranes, made using sol-gel chemistry, could be an ideal solution for acidic and/or oxidizing wastewater streams from processes such as semiconductor manufacturing and mining.

Keywords: ion exchange, membrane, silane chemistry, nanostructure, wastewater

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Authors: Shuko Takeshita

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This study investigates the identity formation of mixed-race children in Japan. From the latter half of the 1980s to the mid-2000s, Japan experienced an 'intermarriage boom,' which was soon followed by a fairly significant number of children born to these unions. These children are now coming of age. Among mixed-race children, some embraced both cultural traditions, while others chose a monocultural path despite exposure to two cultural traditions as they grew up. What factors are involved in shaping the identity of mixed-race children? How does identity formation actually occur in these children? This study addresses these questions through an interview survey of 139 cross-cultural families since 1999, including 23 Pakistani-Japanese families, 20 Turkish-Japanese families, 26 families comprising other international Muslim husbands and Japanese wives, 33 Filipino-Japanese families, and 37 Brazilian-Japanese families. The results of this two-decade-long study reveal that in cases where one cannot tell at first glance that children are mixed race, there is a tendency for them to hide their mixed background due to fear of bullying at school, as well as for their parents to encourage them to do this. To pass as a Japanese is one strategy for avoiding discrimination and prejudice, and it can provide a measure of ethnic security or a way of coping with social intolerance. Certainly, among my informants, there are some children who were bullied or teased at school, and as a result, they stopped attending or transferred to other schools. But the mixed-race experience is not always a negative thing in Japan. There is clearly a double standard involved in that mixed-race children of a Caucasian parent are more readily accepted by society than those of a non-Caucasian parent. The perceived social status of mixed-race individuals is usually understood in relation to the hierarchical positionings of monoracial groups. Mixed-race children could be guaranteed the right to enjoy the benefit of maintaining and developing an identity as a Japanese, in addition to one more identity. We need to encourage a new awareness of the children as agents for a transition from a monocultural system to a multicultural system in Japanese society.

Keywords: identity formation, intermarriage, mixed race, multicultural children

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Authors: M. Caporale

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French Curricula across the US have recently suffered low enrollment and have experienced difficulties with retention, thus resulting in fewer students minoring and majoring in French and enrolling in upper-level classes. Successful undergraduate programs offer French courses with a strong cultural and interdisciplinary or multidisciplinary component. The World Language Curriculum in liberal arts colleges in America needs to take into account the cultural aspects of the language and encourage students to think critically about the country or countries they are studying. Limiting the critical inquiry to language or literature narrowly defined provides and incomplete and stagnant picture of France and the Francophone world in today's global community. This essay discusses the creation and implementation of a hybrid interdisciplinary L1/L2 course titled "Topics in Francophone Cinema" (subtitle "Francophone Women on Screen and Behind the Camera"). Content-based interdisciplinary courses undoubtedly increase the profile of French and Francophone cultural Studies by introducing students of other disciplines to fundamental questions relating to the French and Francophone cultures (in this case, women's rights in the Francophone world). At the same time, this study determines that through targeted reading and writing assignments, sustained aural exposure to L2 through film,and student participation in a one-credit supplementary weekly practicum (creative film writing workshop), significant advances in L2 competence are achieved with students' oral and written production levels evolving from Advanced Low to Advanced-mid, as defined by the ACFL guidelines. Use of differentiated assessment methods for L1/L2 and student learning outcomes for both groups will also be addressed.

Keywords: interdisciplinary, Francophone cultural studies, language competency, content-based

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Authors: Gurkirandeep Kaur, Rana Pratap Yadav

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This experimental study is aimed to examine the radiation characteristics of different plasma structures of a surface wave-driven plasma antenna by an automated measuring system. In this study, a 30 cm long plasma column of argon gas with a diameter of 3 cm is excited by surface wave discharge mechanism operating at 13.56 MHz with RF power level up to 100 Watts and gas pressure between 0.01 to 0.05 mb. The study reveals that a single structured plasma monopole can be modified into an array of plasma antenna elements by forming multiple striations or plasma blobs inside the discharge tube by altering the values of plasma properties such as working pressure, operating frequency, input RF power, discharge tube dimensions, i.e., length, radius, and thickness. It is also reported that plasma length, electron density, and conductivity are functions of operating plasma parameters and controlled by changing working pressure and input power. To investigate the antenna radiation efficiency for the far-field region, an automation-based radiation measuring system has been fabricated and presented in detail. This developed automated system involves a combined setup of controller, dc servo motors, vector network analyzer, and computing device to evaluate the radiation intensity, directivity, gain and efficiency of plasma antenna. In this system, the controller is connected to multiple motors for moving aluminum shafts in both elevation and azimuthal plane whereas radiation from plasma monopole antenna is measured by a Vector Network Analyser (VNA) which is further wired up with the computing device to display radiations in polar plot forms. Here, the radiation characteristics of both continuous and array plasma monopole antenna have been studied for various working plasma parameters. The experimental results clearly indicate that the plasma antenna is as efficient as a metallic antenna. The radiation from plasma monopole antenna is significantly influenced by plasma properties which provides a wider range in radiation pattern where desired radiation parameters like beam-width, the direction of radiation, radiation intensity, antenna efficiency, etc. can be achieved in a single monopole. Due to its wide range of selectivity in radiation pattern; this can meet the demands of wider bandwidth to get high data speed in communication systems. Moreover, this developed system provides an efficient and cost-effective solution for measuring the radiation pattern in far-field zone for any kind of antenna system.

Keywords: antenna radiation characteristics, dynamically reconfigurable, plasma antenna, plasma column, plasma striations, surface wave

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Authors: Elmira Ghanbari, Jan Van Esch, Stephen J. Picken, Sahil Aggarwal

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Low-molecular-weight organogelators form gels by self-assembly into the crystalline network which immobilizes the organic solvent. For single bisamide organogelator systems, the effect of the molecular structure on the molecular interaction and their self-assembly behavior has been explored. The spatial arrangement of bisamide molecules in the gel-state is driven by a combination of hydrogen bonding and Van der Waals interactions. The hydrogen-bonding pattern between the amide groups of bisamide molecules is regulated by the number of methylene spacers; the even number of methylene spacers between two amide groups, in even-spaced bisamides, leads to the antiparallel position of amide groups within a molecule. An even-spaced bisamide molecule with antiparallel amide groups can make two pairs of hydrogen bonding with the molecules on the same plane. The odd-spaced bisamide with a parallel directionality of amide groups can form four independent hydrogen bonds with four other bisamide molecules on different planes. The arrangement of bisamide molecules in the crystalline state and the interaction of these molecules depends on the molecular structure, particularly the parity of the spacer length between the amide groups in the bisamide molecule. In this study, the directionality of amide groups has been exploited as a structural characteristic to affect the arrangement of molecules in the crystalline state and produce different binary bisamide gelators with different degrees of crystallinities. Single odd- and even-spaced single bisamides were synthesized and blended to produce binary bisamide organogelators to be characterized in order to understand the effect of the different directionality of amide groups on the molecular interaction in the crystalline state. The pattern of molecular interactions between these blended molecules, mixing or phase separation, has been monitored via differential scanning calorimetry (DSC) and crystallography techniques; X-ray powder diffraction (XRD) and Small-angle X-ray scattering (SAXS). The formation of lamellar structures for odd- and even-spaced bisamide gelators was confirmed by using SAXS and XRD techniques. DSC results have shown that binary bisamide organogelators with different parity of methylene spacers (odd-even binary blends) have a higher tendency for phase separation compared to the binary bisamides with the same parity (odd-odd or even-even binary blends). Phase separation in binary odd-even bisamides was confirmed by the presence of individual (100) reflections of odd and even lamellar structures. The structural characteristic of bisamide organogelators, the parity of spacer length in binary systems, is a promising tool to control the arrangement of molecules and their crystalline structure.

Keywords: binary bisamide organogelators, crystalline structure, phase separation, self-assembly behavior

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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: Flora Tajiki

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This study investigates the effectiveness of non-surgical and non-medical interventions in treating infertile women with severely diminished ovarian reserve (below one), low Anti-Müllerian Hormone (AMH) levels, and symptoms of early menopause. The intervention included yoga, sunlight exposure, vitamin and mineral supplementation, relaxation techniques, and daily prayers performed both before sleep and upon waking. These methods were applied to women who had shown poor response to high-dose fertility treatments, such as IVF and microinjection cycles, leading to low-quality egg production. The focus was on women with severely reduced ovarian reserve and early menopause symptoms, some of whom continued to experience relatively regular menstrual cycles despite the onset of these symptoms. This treatment was aimed at women for whom conventional fertility methods had been ineffective. The study sample consisted of 120 married women, aged 25 to 45, from the provinces of Tehran, Alborz, and western Iran, with 35 participants completing the intervention. Individual factors such as residence, education, employment status, marriage duration, family infertility history, and previous infertility treatments were examined, with income considered as a contextual variable. The results indicate that AMH may not be a definitive marker of ovarian reserve, as lifestyle modifications, such as those implemented in this study, were associated with increased AMH levels, the return of regular menstrual cycles, and successful pregnancies. No short- or long-term complications were reported during the two-year follow-up, highlighting the potential benefits of non-surgical interventions for women with early menopause symptoms and diminished ovarian reserve.

Keywords: anti-müllerian hormone, infertility, ovarian reserve, early menopause, fertility, women’s health, lifestyle modification, pregnancy

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Authors: Rupam Saikia, Ashim Kanti Dey

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Sonapur is an intense hilly region on the border of Assam and Meghalaya lying in North-East India and is very near to a seismic fault named as Dauki besides which makes the region seismically active. Besides, these recently two earthquakes of magnitude 6.7 and 6.9 have struck North-East India in January and April 2016. Also, the slope concerned for this study is adjacent to NH 44 which for a long time has been a sole important connecting link to the states of Manipur and Mizoram along with some parts of Assam and so has been a cause of considerable loss to life and property since past decades as there has been several recorded incidents of landslide, road-blocks, etc. mostly during the rainy season which comes into news. Based on this issue this paper reports a static and dynamic slope stability analysis of Sonapur which has been carried out in MIDAS GTS NX. The slope being highly unreachable due to terrain and thick vegetation in-situ test was not feasible considering the current scope available so disturbed soil sample was collected from the site for the determination of strength parameters. The strength parameters were so determined for varying relative density with further variation in water content. The slopes were analyzed considering plane strain condition for three slope heights of 5 m, 10 m and 20 m which were then further categorized based on slope angles 30, 40, 50, 60, and 70 considering the possible extent of steepness. Initially static analysis under dry state was performed then considering the worst case that can develop during rainy season the slopes were analyzed for fully saturated condition along with partial degree of saturation with an increase in the waterfront. Furthermore, dynamic analysis was performed considering the El-Centro Earthquake which had a magnitude of 6.7 and peak ground acceleration of 0.3569g at 2.14 sec for the slope which were found to be safe during static analysis under both dry and fully saturated condition. Some of the conclusions were slopes with inclination above 40 onwards were found to be highly vulnerable for slopes of height 10 m and above even under dry static condition. Maximum horizontal displacement showed an exponential increase with an increase in inclination from 30 to 70. The vulnerability of the slopes was seen to be further increased during rainy season as even slopes of minimal steepness of 30 for height 20 m was seen to be on the verge of failure. Also, during dynamic analysis slopes safe during static analysis were found to be highly vulnerable. Lastly, as a part of the study a comparative study on Strength Reduction Method (SRM) versus Limit Equilibrium Method (LEM) was also carried out and some of the advantages and disadvantages were figured out.

Keywords: dynamic analysis, factor of safety, slope stability, strength reduction method

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Authors: Svetlana Guryeva, Inna Kornienko, Elena Petersen

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At present, translational medicine is a rapidly developing branch of biomedicine. The main idea of translational medicine is a practical application of fundamental research. One of the possible applications for translational medicine is researching therapies that improve human age-related organism condition. To fill the gap between experiments and clinical practice, it is necessary to create the standardized system for the investigation of different effects on cellular aging models. In this study, primary human fibroblasts derived from patients of different ages were used as a cellular aging model. The senescence-associated β-galactosidase activity, lipofuscin, γ-H2AX, the reactive oxygen species level, and cell death markers (annexin V/propidium iodide) were used as biomarkers of the cell functional state. The effects of damaging exposures (oxidative stress and heat shock), potential positive factors (metformin and acetaminophen), and their combinations were investigated using the described biomarkers. Oxidative stress and heat shock caused the increase in the levels of all biomarkers, and only the cells from young patients partly coped with stress 3 days after the exposures. Metformin improved the state of pretreatment cells from young and old patients. The acetaminophen did not show significant changes in the biomarker levels compare to the action of metformin. This study proved the opportunity to develop a standardized screening system based on biomarkers of the cell functional state to identify potential positive or negative effects of some physical and chemical exposures. Moreover, such a system can be useful for the aims of regenerative medicine to determine the effect of cell pretreatment before transplantation.

Keywords: biomarkers, primary fibroblasts, regenerative medicine, senescence, test system, translational medicine

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Authors: Pei-Ying Lo, Jing-Hao Ciou, Kai-Cheng Yang, Jia-Huei Zheng, Shih-Hsiang Huang, Kuen-Chan Lee, Er-Chieh Cho

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As-produced CNTs are insoluble in all organic solvents and aqueous solutions have imposed limitations to the use of CNTs. Therefore, how to debundle carbon nanotubes and to modify them for further uses is an important issue. There are several methods for the dispersion of CNTs in water using covalent attachment of hydrophilic groups to the surface of tubes. These methods, however, alter the electronic structure of the nanotubes by disrupting the network of sp2 hybridized carbons. In order to keep the nanotubes’ intrinsic mechanical and electrical properties intact, non-covalent interactions are increasingly being explored as an alternative route for dispersion. Apart from conventional surfactants such as sodium dodecylsulfate (SDS) or sodium dodecylbenzenesulfonate (SDBS) which are highly effective in dispersing CNTs, biopolymers have received much attention as dispersing agents due to the anticipated biocompatibility of the dispersed CNTs. Also, The pyrenyl group is known to interact strongly with the basal plane of graphene via π-stacking. In this study, a highly re-dispersible biopolymer is reported for the synthesis of pyrene-modified poly-L-lysine (PBPL) and poly(D-Glu, D-Lys) (PGLP). To provide the evidence of the safety of the PBPL/CNT & PGLP/CNT materials we use in this study, H1299 and HCT116 cells were incubated with PBPL/CNT & PGLP/CNT materials for toxicity analysis, MTS assays. The results from MTS assays indicated that no significant cellular toxicity was shown in H1299 and HCT116 cells. Furthermore, the fluorescence marker fluorescein isothiocyanate (FITC) was added to PBPL & PGLP dispersions. From the fluorescent measurements showed that the chemical functionalisation of the PBPL/CNT & PGLP/CNT conjugates with the fluorescence marker were successful. The fluorescent PBPL/CNT & PGLP/CNT conjugates could find application in medical imaging. In the next step, the GFP gene is immobilized onto PBPL/CNT conjugates by introducing electrostatic interaction. GFP-transfected cells that emitted fluorescence were imaged and counted under a fluorescence microscope. Due to the unique biocompatibility of PBPL modified CNTs, the GFP gene could be transported into H1299 cells without using antibodies. The applicability of such soluble and chemically functionalised polypeptide/CNT conjugates in biomedicine is currently investigated. We expect that this polypeptide/CNT system will be a safe and multi-functional nanomedical delivery platform and contribute to future medical therapy.

Keywords: carbon nanotube, nanotoxicology, GFP transfection, polypeptide/CNT hybrids

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Authors: Salma Maher, Ahmed Elseragy, Sally Eldeeb

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Nowadays, Urbanism and climate change lead to the rapid growth in energy consumption and the increase of using air-conditioning for cooling. In a hot climate area, there is a need for a new sustainable alternative that is more convenient for an existing situation. The Building envelope controls the heat transfer between the outside and inside the building. While the building façade is the most critical part, types of façade material play a vital role in influences of the energy demand for heating and cooling due to exposure to direct solar radiation throughout the day. Since the beginning of the twentieth century, the use of curtain walls in office buildings façades started to increase rapidly, which lead to more cooling loads in energy consumption. Integrating the living wall system in urban areas as a sustainable renovation and energy-saving method for the built environment will reduce the energy demand of buildings and will also provide environmental benefits. Also, it will balance the urban ecology and enhance urban life quality. The results show that the living wall systems reduce the internal temperature up to 4.0 °C. This research carries on an analytical study by highlighting the different types of living wall systems and verifying their thermal performance, energy-saving, and life potential on the building. These assessing criteria include the reason for using the Living wall systems in the building façade as well as the effect it has upon the surrounding environment. Finally, the paper ends with concluding the effect of using living wall systems on building. And, it suggests a system as long-lasting, and energy-efficient solution to be applied in curtain wall façades in a hot climate area.

Keywords: living wall systems, energy consumption, curtain walls, energy-saving, sustainability, urban life quality

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Authors: Abdulmalik Altuwayjiri, Milad Pirhadi, Mohammed Kalafy, Badr Alharbi, Constantinos Sioutas

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In this study, we investigated the chemical and toxicological characteristics of PM10 in the metropolitan area of Riyadh, Saudi Arabia. PM10 samples were collected on quartz and teflon filters during cold (December 2019–April 2020) and warm (May 2020–August 2020) seasons, including dust and non-dust events. The PM10 constituents were chemically analyzed for their metal, inorganic ions, and elemental and organic carbon (EC/OC) contents. Additionally, the PM10 oxidative potential was measured by means of the dithiothreitol (DTT) assay. Our findings revealed that the oxidative potential of the collected ambient PM10 samples was significantly higher than those measured in many urban areas worldwide. The oxidative potential of the collected ambient PM¹⁰⁻ samples was also higher during dust episodes compared to non-dust events, mainly due to higher concentrations of metals during these events. We performed Pearson correlation analysis, principal component analysis (PCA), and multi-linear regression (MLR) to identify the most significant sources contributing to the toxicity of PM¹⁰⁻ The results of the MLR analyses indicated that the major pollution sources contributing to the oxidative potential of ambient PM10 were soil and resuspended dust emissions (identified by Al, K, Fe, and Li) (31%), followed by secondary organic aerosol (SOA) formation (traced by SO₄-² and NH+₄) (20%), and industrial activities (identified by Se and La) (19%), and traffic emissions (characterized by EC, Zn, and Cu) (17%). Results from this study underscore the impact of transported dust emissions on the oxidative potential of ambient PM10 in Riyadh and can be helpful in adopting appropriate public health policies regarding detrimental outcomes of exposure to PM₁₀-

Keywords: ambient PM10, oxidative potential, source apportionment, Riyadh, dust episodes

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