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Institute of Public Health Newsletter- Volume4, Issue2
Get PDFhttps://scholarworks.uaeu.ac.ae/iphnl/1011/thumbnail.jp
HEAVY METAL BIOACCUMULATION IN BENTHIC FLATFISHES FROM TERRITORIAL WATERS OF FUJAIRAH, UNITED ARAB EMIRATES
Get PDFMarine pollution from anthropogenic sources is a major threat to many coastal and offshore species. A variety of potentially harmful elements are released from wastewater runoff, leached from landfills or industrial effluents. I measured trace metal concentrations in the liver, gills, and muscles of two benthic flatfish species, the halibut (Hippoglossus hippoglossus), and the Dover sole (Solea solea). The primary objective of this thesis was to evaluate the status of the benthic fish species in the Fujairah waters to understand the pollution status of regional waters and assess their effects on human consumption. Inductively Coupled Plasma Optical Emission spectroscopy was used to measure the following trace metals As, Ca, Cd, Co, Cr, Cu, Pb, Mg, Mn, Hg, Mo, Ni, K, P, Na, S, Sr, V, and Zn in a total of 129 prepared samples. The concentration of metals in the liver was higher than the other two organs followed by gills and then muscles. The Dover sole samples generally had higher metal concentrations than the halibut. Differences in the two species could be because of differences in their habitat use and feeding habit. This study offers knowledge and a basis for understanding the level of metal pollution present in the benthic fishes of Fujairah. Although concentrations of heavy metals did not exceed dangerous levels, some of the values appear to indicate rising pollution in the region. Regular monitoring of harmful elements in fish collected from this region and better monitoring of pollution in the environment could help safe guard marine species and human consumers alike
ENERGY-AWARE RESOURCE CONTROL FOR DUAL CONNECTIVITY DEVICES RUNNING MULTIPATH TCP
Get PDFThe introduction of Multipath Transmission Control Protocol (MPTCP) allows uninterrupted data transmission through different wireless interfaces simultaneously. It surpasses the performance and reliability of conventional Transmission Control Protocol (TCP). Alternatively, Software Defined Networking (SDN) has revolutionized traditional network management and control by introducing significant changes. It enables the networks to be programmed through a centralized controller that oversees the entire network. Despite that, energy consumption is a remarkable issue when using dual-connectivity wireless devices, most of which are battery-powered. This thesis work primarily investigates the energy value differences of devices under different congestion control algorithms by using different interface configurations such as WiFi alone, LTE alone and both interfaces together.
Furthermore, the study proposes an algorithm to choose the least energy-consuming combination of node interfaces with the addition of the SDN paradigm. Then, a tuning algorithm using Deep Neural Networking (DNN) is also developed to fine-tune the result into the most accurate version. A real hardware setup with networks of various radio access technologies is used to experimentally assess the algorithm\u27s effectiveness. This research shows that incorporating SDN and neural networks can lower the energy consumption of dual-homed wireless devices. Thus, the efficacy of the proposed algorithms has been confirmed through comprehensive hardware testing
ESTABLISHING A SCOOTABILITY INDEX TO PRIORITISE ROAD AND FOOTWAY INFRASTRUCTURE IMPROVEMENTS FOR SMOOTH AND SAFE E-SCOOTER USAGE
Get PDFThe intensifying use of electric scooters as a form of transportation calls for new infrastructure assessment methods to improve the smoothness and safety of facilities in which these devices are ridden. Despite the extensive research on the infrastructure requirements of bicycles, there is a dearth of studies on electric scooters. This study aims to define the main infrastructure requirements for electric scooters in an urban context. A mixed-methods approach is employed combining quantitative and qualitative data collection and regression analysis. To provide a basis for a so-called multi-dimensional “scootability” index that covers all aspects pertaining to the safety and smoothness of escooter rides, this study extracts the main Scootability features through a comprehensive literature review, combined with the analysis of 139 micro-mobility crashes that occurred in the city of Abu Dhabi in years 2020 and 2021, as well as an analysis of 1230 questionnaire participants\u27 responses. Feature extraction was followed by assessments of roadway and footway conditions, through site observations of those facilities, and actual rider experience appraisals of e-scooter trips made along 93 most common road and footway sub-segments used by Abu Dhabi e-scooter riders. The study modeled the contribution of Scootability features assessed by the researcher on the overall ride quality through linear regression equations, which identified “aesthetic quality” to have the most powerful effect on user satisfaction, followed by “footpath width”, “pathway connectivity”, and “obstacle presence”. The results of the sensitivity analysis showed that all features had a salutary influence on the overall user rating, with “aesthetic quality” having the greatest effect. These results provide invaluable insights for policymakers and urban planners looking to prioritize improving urban facilities to improve e-scooter users experience
BIOCHEMICAL CHARACTRIZATION OF A FRUCTOSYLTRANSFERASE ENZYME FROM A HALOPHILIC ARCHAEON, HALOARCULA MARISMOTUI, FOR BIOTECHNOLOGICAL APPLICATIONS
No full textFructosyltransferase enzymes are involved in the production of fructans, which are polymers of fructose and naturally present in many foods like fruits, vegetables, legumes, and cereals. Fructans with short chain lengths are called Fructooligosaccharides (FOS), which are small dietary fibers having low caloric values and are known as “prebiotics”. Fructans have a broad range of applications in the food, pharmaceutical, cosmetics, and chemical industries. They have unique physiochemical properties and functionalities depending on the source of enzyme used for their production. The present study aimed at the utilization of a recently discovered unique fructosyltransferase enzyme from an extremely halophilic microorganism, Haloarcula marismortui, to produce novel fructans for biotechnological applications. A 1.4 kb fructosyltransferase (ftf) gene from Haloarcula marismortui was cloned in a pET15b vector having a 6xHis Tag at its N-terminus and expressed in the mesophilic host, E.coli, under different growth conditions to optimize the expression of the recombinant enzyme. The expression of the ftf gene in the E.coli BL21(DE3) strain produced an insoluble protein in the form of inclusion bodies. However, soluble, and active recombinant protein has been successfully obtained in the E.coli BL21(DE3) Rosetta strain, which provides rare codons for the expression of recombinant proteins in a heterologous host. Almost 90% pure enzyme was obtained by affinity purification using Ni-NTA column. The detailed biochemical characterization (pH dependence, salt dependence, thermostability, and metal ions stability) of the recombinant enzyme showed that the enzyme works optimally in 2.5 M NaCl and is stable in 1 M, NaCl for 10 days at 4 oC. The pH and temperature optima are 7 in KPi buffer and 40 oC, respectively. The enzyme lost its activity and stability when heated at 60oC and above for 5 minutes. None of the metals tested supported the enzyme activity. The enzyme synthesized more product in the presence of 1 M sucrose compared to 500 mM under optimum assay conditions. The TLC analysis of the product exhibited the presence of a polymer which was found to be inulin by further analysis through NMR. Production of the recombinant halophilic enzyme in a larger quantity to obtain more product for the detailed analysis of linkages among fructose monomers to explore its biotechnological potential remains a challenge for the future
HEAT TRANSFER IN MINI-CHANNEL HEAT EXCHANGER WITH SMOOTH AND PIN-FINS SURFACES
No full textThis research aims to investigate heat transfer of single-phase and two-phase fluids in mini-channel heat exchanger with smooth and pin-fins surfaces. The main goal of the study is to develop a high-performance heat exchanger for thermal management in various processing applications. This research is carried out using computational fluid dynamics (CFD) modeling and experimentations. The proposed method is to use enhanced structured pin-fins surfaces in a mini-channel heat exchanger to improve heat transfer. The pin-fin microchannel heat exchanger is investigated using a CFD method with single-phase fluid (water, air). The experimental investigations are conducted using single-phase and two-phase fluid involving condensation. The obtained experimental results show improvement of heat transfer coefficients in the mini-channel heat exchanger with micro pin-fin surfaces at the expense of increased pressure drop. The theoretical modeling study and experimental investigation provides heat transfer results that are useful in understanding enhanced heat transfer and are valuable to the heat transfer research field. The CFD analysis is carried out for Reynold numbers between 50 – 250. The inlet temperatures for hot and cold fluids are set to 335 K and 285 K, respectively. It was found that the maximum effectiveness occurs at lowest Reynolds number, and it is 47.4%, 64.8%, and 65.8% for surface without fins, surface with circular fins, and surface with square fins respectively.
The experimental testing is carried out on aluminum surface with a channel that has a length of 270, width of 30 mm, and height of 1.3 mm. Both smooth and surface with pin-fins are tested experimentally, with pin-fins are on the bottom in inline arrangement, and they have a height and diameter of 1 mm. The inlet temperature at hot fluid and cold fluid are fixed to 293 K and 353 K, respectively. It was found that pressure drop increased as the Reynolds number increased, and turbulent flow showed an even greater increase in pressure drop. The flow rates of air varied from 35 LPM to 77 LPM, and the cold fluid has different flow rates, which are chosen based on the heat capacity ratios of 0.25, 0.5, 0.75, and 1. The experiment showed that an increase in the ratio of heat capacity causes an increase in the convective and overall heat transfer coefficients. Increasing the ratio increased the cooling rate, which also increased the difference in temperatures between the two loops and increased the heat transfer rate. It was found the heat transfer rate is greater in enhanced surfaces with pin-fins in all single phase and two-phase fluids with condensation
ASSESSING THE PERCEPTIONS OF SCHOOL CHILDREN WITH AUTISM SPECTRUM DISORDER OF ARTIFICIAL GREEN ELEMENTS IN HOT ARID REGION
No full textRecently, global statistics demonstrated a continued increase in Autism Spectrum Disorder (ASD) worldwide, especially in Gulf countries, where the United Arab Emirates (UAE) ranks second in terms of autism prevalence. Studies emphasized the positive effects of green elements on the academic performance and skills of school children. The presence of indoor plants can lead to benefits such as stress reduction and positive health and well-being in children with ASD. However, green elements are less utilized in Al Ain schools due to difficulty in maintaining natural plants in buildings. This study aims to examine the perceptions of children with Autism Spectrum Disorder (ASD) of Artificial Green Elements (AGEs). We hypothesize that AGEs will exert the same positive impact as Real Green Elements (RGEs) on the psychological and emotional health of children with ASD. Toward this end, the study recruited 17 children with ASD and 20 children without ASD aged 5–11 years. This study employed Personal Construct Psychology (PCP) by using Qualitative Grids for construing children’s meanings. The results showed that children with Autism Spectrum Disorder enjoyed spending long periods in spaces with AGEs, which is considered a positive response. The findings contribute to reflect the green elements importance for children with and without ASD, that can enhance the school design guideline in Al Ain city
THE ASSOCIATION BETWEEN ADDED SUGAR AND ABDOMINAL OBESITY IN ADULTS
No full textExcessive body fat accumulation is a complicated medical condition known as obesity. Obesity increases the risk of chronic diseases including type 2 diabetes mellitus, cardiovascular disease, and several types of cancer. Numerous studies have shown that adults who regularly consume added sugar, mostly from sugar sweetened beverages, are more likely to be overweight or obese and/or abdominal obesity, however results remain controversial. The primary objective was to evaluate the relationship between Greek adults’ consumption of added sugar and abdominal obesity. The primary outcome was to investigate the intakes of added sugars in relation to weight status, fat mass, and specific biomarkers in adults. Data were analyzed from a representative population based survey of 968 adults (365 males and 603 females) in the Hellenic National Nutrition and Health Survey (HNNHS). Computer-Assisted Personal Interview (CAPI) software was used to gather the data of sociodemographic and lifestyle. Two 24-hour recalls were collected to calculate nutrient consumption. Multiple logistic regression analysis was conducted to assess the association accounting for multiple sociodemographic factors associated with weight status and that differed by sugar percentage consumption. the 10% cutoff of added sugar intake in relation to total energy intake was used for the final analysis. By analyzing the data utilizing the regression models encompassing dietary habits, this study investigated the association between added sugar consumption and abdominal obesity in Greek adults, finding no significant association on waist size or body mass index, regardless of whether added sugar intake exceeded 10% of total calories. Factors like physical activity and education level were identified as crucial influencers of these outcomes. With an average added sugar intake of 5.7%, falling within the recommendations, the study suggests a complex interplay of lifestyle factors affecting abdominal obesity. The findings of this study contribute to a more comprehensive understanding of the intricate role of lifestyle in terms of physical activity, and education as the sociodemographic determinant of abdominal obesity, paving the way for targeted strategies aimed at mitigating its prevalence. Differences in findings observed compared to other studies may be related to the food vehicle that contributes to added sugar intake. This research bridges a critical gap by investigating the association of added sugar intake on abdominal obesity in Greek adults, addressing a scarcity of studies in this specific population. The study\u27s focus on nuanced dietary assessments and lifestyle factors fills a crucial void, providing a more comprehensive understanding of the complex relationship between added sugar consumption and obesity outcomes. Type of foods and dietary patterns may be critical in this association
IMPACT OF PHYSICAL INACTIVITY ON GLUCOSE METABOLISM AND SKELETAL MUSCLE SECRETIONS IN HEALTHY TRAINED RATS AND POTENTIAL COUNTERACTING EFFECT OF EXERCISE AND PROTOCATECHUIC ACID
No full textModern societies have significantly transformed people\u27s lifestyles, leading to a substantial increase in physical inactivity, which concerns 23% of adults and 81% of adolescents worldwide. Physical inactivity is a major factor contributing to the emergence of chronic diseases, most prominently Type 2 Diabetes (T2D), which exhibits a high prevalence in many countries. T2D is characterized by elevated blood glucose levels due to cells’ responsiveness to insulin. The shift towards inactivity likely occurred more rapidly than the genome\u27s capacity to adapt, resulting in the metabolic dysfunctions underlying the development of T2D. Skeletal muscle is crucial in the onset of these metabolic dysfunctions, not solely because of its high metabolic activity but also owing to its endocrine function. The skeletal muscle can release a range of proteins to establish communication with peripheral organs to regulate metabolism. Nevertheless, the T2D underlying mechanisms encompassing the detrimental alterations in muscle secretions resulting from physical inactivity still require a comprehensive understanding. In addition to physical activity, phenolic compounds, particularly protocatechuic acid (PCA), affects insulin sensitivity and glucose metabolism. The contribution of PCA to the regulation of glucose metabolism and its potential synergy with physical activity still require exploration.
This study seeks to examine the shifts in metabolic processes that transpire in the transition from an active lifestyle to a state of physical inactivity, to ascertain the contribution of muscle secretions to these alterations, and to assess whether aerobic activity and PCA can ameliorate the adverse consequences linked to inactivity, independently and in combination. A five-arm trial was conducted on 47 healthy male Wistar rats, trained for 4-weeks (T0-T4), then randomly divided into 5 groups: 8-weeks physical inactivity without PCA (AT4) or with PCA (AT4-PCA); physical activity (1 hour/day, 5 days/week at 25 meter/minutes) for 4 more weeks without PCA (AT8) or with PCA (AT8-PCA); and vehicle control (VC). The study continued for 12-weeks, sacrificed 6 rats at T0 and T4, 4 per group at T8, and 3 per group at T12. Body weight, feed intake, intraperitoneal glucose tolerance test (IPGTT), glucose, serum lipid profile, liver enzymes, serum insulin, muscle secretions (interleukin-6 (IL-6), insulin-like growth factor-1 (IGF-1), fibroblast growth factor-21 (FGF-21), myostatin, and irisin), phosphofructokinase (PFK) and hexokinase (HK) activity, muscle glycogen, pyruvate, and expression of insulin signaling pathways, glucose transporter type-4 (GLUT-4), lipoprotein lipase (LPL), adipose triglyceride lipase (ATGL), and fatty acid transport protein-4 (FATP-4) were analyzed in muscle at T0, T4, T8, and T12. Additionally, for the in vitro experiment, C2C12 myotubes were cultured and received four treatments: control, PCA, insulin resistance (IR), and IR-PCA. Conditioned media from treated C2C12 myotubes was used to incubate HepG2 cells and 3T3-L1 adipocytes. Glucose uptake and protein expressions of signaling pathways were analyzed in all three cell lines.
Aerobic activity for 4-weeks improved glucose tolerance, lipid profile, liver enzymes, enhanced muscular HK activity, LPL and ATGL expression, myokines (IGF-1, IL-6, and FGF-21), insulin signaling pathways, and reduced myostatin in muscle, but a greater improvement was observed after 8 weeks of physical activity. In contrast, the beneficial effects of physical activity disappeared after only 4-weeks of inactivity (at T8 and T12), resulting in a reduction of IGF-1, IL-6, HK activity, LPL, and ATGL expression and increased pyruvate, glycogen, myostatin, and FGF-21 in muscle, which led to a negative alteration of the signaling pathway and glucose metabolism. Further, PCA treatment for 8-weeks mitigated the negative effects of inactivity by modulating insulin, myostatin, FGF-21, glucose tolerance, and GLUT-4 expression. Combining PCA dose with training (8-weeks) improved irisin level, IRS-1 expression, glycogen, and reduced PFK. The in vitro experiment highlighted the potential of PCA to regulate the crosstalk between muscle and other organs, ultimately regulating glucose metabolism. GLUT-4 expression was increased in the liver and adipose cells cultivated in the conditioned media obtained from PCA-treated C2C12 myotubes, enhancing glucose uptake in both cells.
In conclusion, reduced muscle contraction due to inactivity hindered skeletal muscle secretions, negatively influencing insulin signaling pathways and increasing the risk for T2D via a potential disruption of organs-crosstalk. PCA was highlighted as a potential counteracting agent against the metabolic alterations associated with inactivity. In addition to advocating for a phenolic-rich diet and regular engagement in aerobic physical activity, these findings can play a pivotal role in shaping novel therapeutic and preventive strategies for T2D
موقف القانون الإماراتي من الصياغة النموذجية للعقود
Get PDFStandard form contracts are widely used in various economic transactions, which contributes to a convenient and time saving method to create agreements that are compatible with contractual terms. The importance of this study is that when the consumer wants to obtain a good or service, the seller will offer him a standard form contract to sign, and this consumer may be forced to enter into this contract to satisfy his needs, even if this good or service is not one of the basics for society as a whole, but it is necessary for him as an individual.
Additionally, this study explores the concept of standard form contracts, their legal adaptation, and their impact on the freedom of contracting. The study sheds light on how these contracts affect the principle of will power, which may lead to the spread of arbitrary terms. In addition, the study looks at the extent to which the contracting parties are aware of the terms of standard form contracts, and the role of each of the legislators, the judiciary, and the administrative authorities in addressing these issues.
Clearly, the study concluded that the UAE law did not regulate standard form contracts with specific articles, but rather they were regulated by the general rules in the Civil Transactions Law, and these rules are not compatible with these contracts, also the UAE judiciary did not adopt the modern concept of compliance, although the legislative articles allow it, and the modern concept compliance has evolved in response to the need to protect the consumer. According to modern principles, the contract is considered compliance once the contract is prepared by the other party, and it is he who defines the rights and obligations arising from the contract in a manner that achieves his interest, and does not accept discussion or negotiation in these terms