Search results for: particle mass concentration

Authors: Dipanshu Sur, Ratnabali Chakravorty

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Introduction: Polycystic ovary syndrome (PCOS) is the most common metabolic abnormality such as changes in lipid profile, diabetes, hypertension and metabolic syndrome occurring in women. Hypovitaminsis D was found to be associated with the development of obesity and insulin resistance in women with PCOS. Aim: To evaluate the association of vitamin D levels in obese and non-obese patients with PCOS in an East Indian populations. Methods: A case control study was conducted. It enrolled 100 cases of PCOS based on Rotterdam criteria and 100 ovulatory normal cases matched for their age and BMI. Vitamin D levels were compared in the obese and non-obese PCOS groups and also with the controls. Results: The mean age of subjects was 29.48 ± 3.29 years in the PCOS group and 26.24 ± 2.56 years in the control group. Hypovitaminosis D was present in 75 out of 100 PCOS women (75.0%) and 25 women (25.0%) showed sufficient 25OHD levels ≥30 ng/ml. Women with PCOS had significantly lower total serum calcium (8.4 ± 0.25 mg/dl versus 9.8 ± 0.17 mg/dl in controls), and 25 OHD (21.2 ± 2.56 ng/ml versus 32.6 ± 2.23 ng/ml in control group) than ovulatory normal women. This difference remained significant for both groups after adjustment for BMI. Obese women in both groups had significantly lower concentration of calcium and 25OHD than normal weight patients in this study. Conclusion: Our study shows majority of the patients and controls had vitamin D deficiency and there was significant difference in the vitamin D levels in PCOS group and controls as well as obese and non-obese groups. This may reflect the vitamin D deficiency status of the community. Vitamin D deficiency should demands immediate attention as it is a severe problem among the East Indian population.

Keywords: vitamin D deficiency, polycystic ovary syndrome, obese, hypovitaminsis D

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Authors: Ladislav Écsi, Roland Jančo

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Contemporary multiplicative plasticity models assume that the body's intermediate configuration consists of an assembly of locally unloaded neighbourhoods of material particles that cannot be reassembled together to give the overall stress-free intermediate configuration since the neighbourhoods are not necessarily compatible with each other. As a result, the plastic deformation gradient, an inelastic component in the multiplicative split of the deformation gradient, cannot be integrated, and the material particle moves from the initial configuration to the intermediate configuration without a position vector and a plastic displacement field when plastic flow occurs. Such behaviour is incompatible with the continuum theory and the continuum physics of elastoplastic deformations, and the related material models can hardly be denoted as truly continuum-based. The paper presents a proper continuum-based reformulation of current problems in finite strain plasticity. It will be shown that the incompatible neighbourhoods in real material are modelled by the product of the plastic multiplier and the yield surface normal when the plastic flow is defined in the current configuration. The incompatible plastic factor can also model the neighbourhoods as the solution of the system of differential equations whose coefficient matrix is the above product when the plastic flow is defined in the intermediate configuration. The incompatible tensors replace the compatible spatial plastic velocity gradient in the former case or the compatible plastic deformation gradient in the latter case in the definition of the plastic flow rule. They act as local imperfections but have the same position vector as the compatible plastic velocity gradient or the compatible plastic deformation gradient in the definitions of the related plastic flow rules. The unstressed intermediate configuration, the unloaded configuration after the plastic flow, where the residual stresses have been removed, can always be calculated by integrating either the compatible plastic velocity gradient or the compatible plastic deformation gradient. However, the corresponding plastic displacement field becomes permanent with both elastic and plastic components. The residual strains and stresses originate from the difference between the compatible plastic/permanent displacement field gradient and the prescribed incompatible second-order tensor characterizing the plastic flow in the definition of the plastic flow rule, which becomes an assignment statement rather than an equilibrium equation. The above also means that the elastic and plastic factors in the multiplicative split of the deformation gradient are, in reality, gradients and that there is no problem with the continuum physics of elastoplastic deformations. The formulation is demonstrated in a numerical example using the regularized Mooney-Rivlin material model and modified equilibrium statements where the intermediate configuration is calculated, whose analysis results are compared with the identical material model using the current equilibrium statements. The advantages and disadvantages of each formulation, including their relationship with multiplicative plasticity, are also discussed.

Keywords: finite strain plasticity, continuum formulation, regularized Mooney-Rivlin material model, compatibility

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Authors: R. Charoen, S. Tipkanon, W. Savedboworn, N. Phonsatta, A. Panya

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Rice bran protein hydrolysates (RBPH) were prepared from defatted rice bran of two different Thai rice cultivars (Plai-Ngahm-Prachinburi; PNP and Khao Dok Mali 105; KDM105) using an enzymatic method. This research aimed to optimize enzyme-assisted protein extraction. In addition, the functional properties of RBPH and their stabilities to environmental stresses including pH (3 to 8), ionic strength (0 mM to 500 mM) and the thermal treatment (30 °C to 90 °C) were investigated. Results showed that enzymatic process for protein extraction of defatted rice bran was as follows: enzyme concentration 0.075 g/ 5 g of protein, extraction temperature 50 °C and extraction time 4 h. The obtained protein hydrolysate powders had a degree of hydrolysis (%) of 21.05% in PNP and 19.92% in KDM105. The solubility of protein hydrolysates at pH 4-6 was ranged from 27.28-38.57% and 27.60-43.00% in PNP and KDM105, respectively. In general, antioxidant activities indicated by total phenolic content, FRAP, ferrous ion-chelating (FIC), and 2,2’-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) of KDM105 had higher than PNP. In terms of functional properties, the emulsifying activity index (EAI) was was 8.78 m²/g protein in KDM105, whereas PNP was 5.05 m²/g protein. The foaming capacity at 5 minutes (%) was 47.33 and 52.98 in PNP and KDM105, respectively. Glutamine, Alanine, Valine, and Leucine are the major amino acid in protein hydrolysates where the total amino acid of KDM105 gave higher than PNP. Furthermore, we investigated environmental stresses on the stability of 5% oil in water emulsion (5% oil, 10 mM citrate buffer) stabilized by RBPH (3.5%). The droplet diameter of emulsion stabilized by KDM105 was smaller (d < 250 nm) than produced by PNP. For environmental stresses, RBPH stabilized emulsions were stable at pH around 3 and 5-6, at high salt (< 400 mM, pH 7) and at temperatures range between 30-50°C.

Keywords: functional properties, oil in water emulsion, protein hydrolysates, rice bran protein

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Authors: Shadi Fathi, Moura Mehravar, Mujib Rahman

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The railwaytransportation network in the UK is over 100 years old and is known as one of the oldest mass transit systems in the world. This aged track network requires frequent closure for maintenance. One of the main reasons for closure is inadequate drainage due to the leakage in the buried drainage pipes. The leaking water can cause localised subgrade weakness, which subsequently can lead to major ground/substructure failure.Different condition assessment methods are available to assess the railway substructure. However, the existing condition assessment methods are not able to detect any local ground weakness/damageand provide details of the damage (e.g. size and location). To tackle this issue, a hybrid back-analysis technique based on artificial neural network (ANN) and genetic algorithm (GA) has been developed to predict the substructurelayers’ moduli and identify any soil weaknesses. At first, afinite element (FE) model of a railway track section under Falling Weight Deflection (FWD) testing was developed and validated against field trial. Then a drainage pipe and various scenarios of the local defect/ soil weakness around the buried pipe with various geometriesand physical properties were modelled. The impact of the soil local weaknesson the track surface deflection wasalso studied. The FE simulations results were used to generate a database for ANN training, and then a GA wasemployed as an optimisation tool to optimise and back-calculate layers’ moduli and soil weakness moduli (ANN’s input). The hybrid ANN-GA back-analysis technique is a computationally efficient method with no dependency on seed modulus values. The modelcan estimate substructures’ layer moduli and the presence of any localised foundation weakness.

Keywords: finite element (FE) model, drainage defect, falling weight deflectometer (FWD), hybrid ANN-GA

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Authors: L. Cesari, L. Canabady-Rochelle, F. Mutelet

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The thermal conversion of lignin produces bio-oils that contain many compounds with high added-value such as phenolic compounds. In order to efficiently extract these compounds, the possible use of choline bis(trifluoromethylsulfonyl)imide [Choline][NTf2] ionic liquid was explored. To this end, a multistep approach was implemented. First, binary (phenolic compound and solvent) and ternary (phenolic compound and solvent and ionic liquid) solutions were investigated. Eight binary systems of phenolic compound and water were investigated at atmospheric pressure. These systems were quantified using the turbidity method and UV-spectroscopy. Ternary systems (phenolic compound and water and [Choline][NTf2]) were investigated at room temperature and atmospheric pressure. After stirring, the solutions were let to settle down, and a sample of each phase was collected. The analysis of the phases was performed using gas chromatography with an internal standard. These results were used to quantify the values of the interaction parameters of thermodynamic models. Then, extractions were performed on synthetic solutions to determine the influence of several operating conditions (temperature, kinetics, amount of [Choline][NTf2]). With this knowledge, it has been possible to design and simulate an extraction process composed of one extraction column and one flash. Finally, the extraction efficiency of [Choline][NTf2] was quantified with real bio-oils from lignin pyrolysis. Qualitative and quantitative analysis were performed using gas chromatographic connected to mass spectroscopy and flame ionization detector. The experimental measurements show that the extraction of phenolic compounds is efficient at room temperature, quick and does not require a high amount of [Choline][NTf2]. Moreover, the simulations of the extraction process demonstrate that [Choline][NTf2] process requires less energy than an organic one. Finally, the efficiency of [Choline][NTf2] was confirmed in real situations with the experiments on lignin pyrolysis bio-oils.

Keywords: bio-oils, extraction, lignin, phenolic compounds

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Authors: Shreya Ghosh, Akansha Garg, Chayanika Kala, Ashwani Kumar Thakur

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Background: Granuloma formation is one of the characteristic features of tuberculosis. Besides, chronic inflammation underlying tuberculosis is often indicated by an increase in the concentration of serum amyloid A (SAA) protein. The connection between tuberculosis and SAA-driven secondary amyloidosis is well documented. However, SAA-derived amyloid deposition start sites are not well understood in tuberculosis and other chronic inflammatory conditions. It was hypothesized that granuloma could be a potential site for an amyloid deposition because both SAA protein and proteases that cleave SAA into aggregation-prone fragments are reported to be present in the granuloma. Here the authors have shown the presence of SAA-derived amyloid deposits in the granuloma of tuberculosis patients. Methodology: Over a period of two years, tuberculosis patients were screened, and biopsies were collected from the affected organs of the patients. The gold standard, Congo red dye staining, was used to identify amyloid deposits in the tissue sections of tuberculosis patients containing granulomatous structure. Results: 11 out of 150 FFPE biopsy specimens of tuberculosis patients showed eosinophilic hyaline-rich deposits surrounding granuloma. Upon Congo red staining, these deposits exhibited characteristic apple-green birefringence under polarized light, confirming amyloid deposits. Further, upon immunohistochemical staining with anti-SAA, the amyloid enriched areas showed positive immunoreactivity. Conclusion: In this pilot study, we have shown that granuloma can be a potential site for serum amyloid A-derived amyloid formation in tuberculosis patients. Moreover, the presence of amyloid gave significant cues that granuloma might be a probable amyloid deposition start in tuberculosis patients. This study will set a stage to expand the clinical and fundamental research in the understanding of amyloid formation in granuloma underlying tuberculosis and chronic inflammatory conditions.

Keywords: amyloid, granuloma, periphery, serum amyloid A, tuberculosis

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Authors: Nadia H. Mohammed, Anmar Al-Taie, Fadia H. Al-Sultany

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Although breast cancer prevalence continues to increase, mortality has been decreasing as a result of early detection and improvement in adjuvant systemic therapy. Nevertheless, this disease required further efforts to understand and identify the associated potential risk factors that could play a role in the prevalence of this malignancy among Iraqi women. The objective of this study was to assess the perception of certain predictive risk factors on the prevalence of breast cancer types among a sample of Iraqi women diagnosed with breast cancer. This was a retrospective observational study carried out at National Cancer Research Center in College of Medicine, Baghdad University from November 2017 to January 2018. Data of 100 patients with breast cancer whose biopsies examined in the National Cancer Research Center were included in this study. Data were collected to structure a detailed assessment regarding the patients’ demographic, medical and cancer records. The majority of study participants (94%) suffered from ductal breast cancer with mean age 49.57 years. Among those women, 48.9% were obese with body mass index (BMI) 35 kg/m². 68.1% of them had positive family history of breast cancer and 66% had low parity. 40.4% had stage II ductal breast cancer followed by 25.5% with stage III. It was found that 59.6% and 68.1% had positive oestrogen receptor sensitivity and positive human epidermal growth factor (HER2/neu) receptor sensitivity respectively. In regard to the impact of prediction of certain variables on the incidence of ductal breast cancer, positive family history of breast cancer (P < 0.0001), low parity (P< 0.0001), stage I and II breast cancer (P = 0.02) and positive HER2/neu status (P < 0.0001) were significant predictive factors among the study participants. The results from this study provide relevant evidence for a significant positive and potential association between certain risk factors and the prevalence of breast cancer among Iraqi women.

Keywords: Ductal Breast Cancer, Hormone Sensitivity, Iraq, Risk Factors

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Authors: Gerald Gwamba

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Formation and oil well sand production is one of the greatest and oldest concerns for the Oil and gas industry. The production of sand particles may vary from very small and limited amounts to far elevated levels which has the potential to block or plug the pore spaces near the perforated points to blocking production from surface facilities. Therefore, the timely and reliable investigation of conditions leading to the onset or quantifying sanding while producing is imperative. The challenges of sand production are even more elevated while producing in Waxy and Heavy wells with Clay Fine sands (WHFC). Existing research argues that both waxy and heavy hydrocarbons exhibit far differing characteristics with waxy more paraffinic while heavy crude oils exhibit more asphaltenic properties. Moreover, the combined effect of WHFC conditions presents more complexity in production as opposed to individual effects that could be attributed to a consolidation of a surmountable opposing force. However, research on a combined high WHFC system could depict a better representation of the surmountable effect which in essence is more comparable to field conditions where a one-sided view of either individual effects on sanding has been argued to some extent misrepresentative of actual field conditions since all factors act surmountably. In recognition of the limited customized research on sand production studies with the combined effect of WHFC however, our research seeks to apply the Design of Experiments (DOE) methodology based on latest literature to analyze the relationship between various interparticle factors in relation to selected sand control methods. Our research aims to unearth a better understanding of how the combined effect of interparticle factors including: strength, cementation, particle size and production rate among others could better assist in the design of an optimal sand control system for the WHFC well conditions. In this regard, we seek to answer the following research question: How does the combined effect of interparticle factors affect the optimization of sand control systems for WHFC wells? Results from experimental data collection will inform a better justification for a sand control design for WHFC. In doing so, we hope to contribute to earlier contrasts arguing that sand production could potentially enable well self-permeability enhancement caused by the establishment of new flow channels created by loosening and detachment of sand grains. We hope that our research will contribute to future sand control designs capable of adapting to flexible production adjustments in controlled sand management. This paper presents results which are part of an ongoing research towards the authors' PhD project in the optimization of sand control systems for WHFC wells.

Keywords: waxy-heavy oils, clay-fine sands, sand control optimization, interparticle factors, design of experiments

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Authors: Adeshina Fadeyibi

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Application of pure thermoplastic film in food packaging is greatly limited because of its poor service performance, often enhanced by the addition of organic or inorganic particles in the range of 1–100 nm. Thus, this study was conducted to develop cassava starch zinc-nanocomposite films for applications in food packaging. Three blending ratios of 1000 g cassava starch, 45–55 % (w/w) glycerol and 0–2 % (w/w) zinc nanoparticles were formulated, mixed and mechanically homogenized to form the nanocomposite. Thermoplastic were prepared, from a dispersed mixture of 24 g of the nanocomposite and 600 ml of distilled water, and heated to 90oC for 30 minutes. Plastic molds of 350 ×180 mm dimension and 8, 10 and 12 mm depths were used for film casting and drying at 60oC and 80 % RH for 24 hour. The average thicknesses of the dried films were found to be 15, 16 and 17 µm. The films were characterized based on their barrier, thermal, mechanical and structural properties. The results show that the oxygen and water vapor barrier properties increased with glycerol concentration and decreased with thickness; but the full width at half maximum (FWHM) and d- spacing increased with thickness. The higher degree of d- spacing obtained is a consequence of higher polymer intercalation and exfoliation. Also, only 2 % weight degradation was observed when the films were exposed to temperature between 30–60oC; indicating that they are thermally stable and can be used for packaging applications in the tropics. The mechanical properties of the film were higher than that of the pure thermoplastic but comparable with the LDPE films. The information on the characterized attributes and optimization of the cassava starch zinc-nanocomposite films justifies their alternative application to pure thermoplastic and conventional films for food packaging.

Keywords: synthesis, characterization, casaava Starch, nanocomposite film, packaging

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Authors: Luís Rocha, Adam Gąska, Enrico Savio, Michael Marxer, Christoph Battaglia

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The changes observed in the last years in the field of manufacturing and production engineering, popularly known as "Fourth Industry Revolution", utilizes the achievements in the different areas of computer sciences, introducing new solutions at almost every stage of the production process, just to mention such concepts as mass customization, cloud computing, knowledge-based engineering, virtual reality, rapid prototyping, or virtual models of measuring systems. To effectively speed up the production process and make it more flexible, it is necessary to tighten the bonds connecting individual stages of the production process and to raise the awareness and knowledge of employees of individual sectors about the nature and specificity of work in other stages. It is important to discover and develop a suitable education method adapted to the specificities of each stage of the production process, becoming an extremely crucial issue to exploit the potential of the fourth industrial revolution properly. Because of it, the project “Train4Dim” (T4D) intends to develop complex training material for digital manufacturing, including content for design, manufacturing, and quality control, with a focus on coordinate metrology and portable measuring systems. In this paper, the authors present an approach to using an active learning methodology for digital manufacturing. T4D main objective is to develop a multi-degree (apprenticeship up to master’s degree studies) and educational approach that can be adapted to different teaching levels. It’s also described the process of creating the underneath methodology. The paper will share the steps to achieve the aims of the project (training model for digital manufacturing): 1) surveying the stakeholders, 2) Defining the learning aims, 3) producing all contents and curriculum, 4) training for tutors, and 5) Pilot courses test and improvements.

Keywords: learning, Industry 4.0, active learning, digital manufacturing

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Authors: Anoff Anim, Lila Mahmoud, Maria Katsikogianni, Sanjit Nayak

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Sustained and controlled delivery of antimicrobial drugs have been largely studied recently using metal organic frameworks (MOFs)and different polymers. However, much attention has not been given to combining both MOFs and biodegradable polymers, which would be a good strategy in providing a sustained gradual release of the drugs. Herein, we report a comparative study of the sustained and controlled release of widely used antibacterial drugs, cephalexin and metronidazole, from zinc-based MOF-5 incorporated in biodegradable polycaprolactone (PCL) and poly-lactic glycolic acid (PLGA) membranes. Cephalexin and metronidazole were separately incorporated in MOF-5 post-synthetically, followed by their integration into biodegradable PLGA and PCL membranes. The pristine MOF-5 and the loaded MOFs were thoroughly characterized by FT-IR, SEM, TGA and PXRD. Drug release studies were carried out to assess the release rate of the drugs in PBS and distilled water for up to 48 hours using UV-Vis Spectroscopy. Four bacterial strains from both the Gram-positive and Gram-negative types, Staphylococus aureus, Staphylococuss epidermidis, Escherichia coli, Acinetobacter baumanii, were tested against the pristine MOF, pure drugs, loaded MOFs and the drug-loaded MOF-polymer composites. Metronidazole-loaded MOF-5 composite of PLGA (PLGA-Met@MOF-5) was found to show highest efficiency to inhibit the growth of S. epidermidis compared to the other bacteria strains while maintaining a sustained minimum inhibitory concentration (MIC). This study demonstrates that the combination of biodegradable MOF-polymer composites can provide an efficient platform for sustained and controlled release of antimicrobial drugs and can be a potential strategy to integrate them in biomedical devices.

Keywords: antimicrobial resistance, biodegradable polymers, cephalexin, drug release metronidazole, MOF-5, PCL, PLGA

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Authors: Soukaina Ounss, Hamid Mounir, Abdellatif El Marjani

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Sandwich materials with composite reinforced skins are mostly required in advanced construction applications with a view to ensure resistant structures. Their lightweight, their high flexural stiffness and their optimal thermal insulation make them a suitable solution to obtain efficient structures with performing rigidity and optimal energy safety. In this paper, the mechanical behavior of a sandwich beam with composite skins reinforced by unidirectional carbon fibers is investigated numerically through analyzing the impact of reinforcements specifications on the longitudinal elastic modulus in order to select the adequate sandwich configuration that has an interesting rigidity and an accurate convergence to the analytical approach which is proposed to verify performed numerical simulations. Therefore, concerned study starts by testing flexion performances of skins with various fibers orientations and volume fractions to determine those to use in sandwich beam. For that, the combination of a reinforcement inclination of 30° and a volume ratio of 60% is selected with the one with 60° of fibers orientation and 40% of volume fraction, this last guarantees to chosen skins an important rigidity with an optimal fibers concentration and a great enhance in convergence to analytical results in the sandwich model for the reason of the crucial core role as transverse shear absorber. Thus, a resistant sandwich beam is elaborated from a face-sheet constituted from two layers of previous skins with fibers oriented in 60° and an epoxy core; concerned beam has a longitudinal elastic modulus of 54 Gpa (gigapascal) that equals to the analytical value by a negligible error of 2%.

Keywords: fibers orientation, fibers volume ratio, longitudinal elastic modulus, sandwich beam

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Authors: Cody Stolle, Mojdeh Asadollahipajouh, Khaleb Pafford, Jada Iwuoha, Samantha White, Becky Mueller

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Battery-electric vehicles (BEVs) are growing in sales and popularity in the United States as an alternative to traditional internal combustion engine vehicles (ICEVs). BEVs are generally heavier than corresponding models of ICEVs, with large battery packs located beneath the vehicle floorpan, a “skateboard” chassis, and have front and rear crush space available in the trunk and “frunk” or front trunk. The geometrical and frame differences between the vehicles may lead to incompatibilities with gasoline vehicles during vehicle-to-vehicle crashes as well as run-off-road crashes with roadside barriers, which were designed to handle lighter ICEVs with higher centers-of-mass and with dedicated structural chasses. Crash data were collected from 10 states spanning a five-year period between 2017 and 2021. Vehicle Identification Number (VIN) codes were processed with the National Highway Traffic Safety Administration (NHTSA) VIN decoder to extract BEV models from ICEV models. Crashes were filtered to isolate only vehicles produced between 2010 and 2021, and the crash circumstances (weather, time of day, maximum injury) were compared between BEVs and ICEVs. In Washington, 436,613 crashes were identified, which satisfied the selection criteria, and 3,371 of these crashes (0.77%) involved a BEV. The number of crashes which noted a fire were comparable between BEVs and ICEVs of similar model years (0.3% and 0.33%, respectively), and no differences were discernable for the time of day, weather conditions, road geometry, or other prevailing factors (e.g., run-off-road). However, crashes involving BEVs rose rapidly; 31% of all BEV crashes occurred in just 2021. Results indicate that BEVs are performing comparably to ICEVs, and events surrounding BEV crashes are statistically indistinguishable from ICEV crashes.

Keywords: battery-electric vehicles, transportation safety, infrastructure crashworthiness, run-off-road crashes, ev crash data analysis

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Authors: Abdalraheem Huwaysh, Khalil Al Samarrai, Yasmin ElAhmar

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Water quality is an important factor that determines its usage for domestic, agricultural and industrial uses. This study was carried out through the Tajoura Area, Jifarah Plain, Northwest Libya. Chemical and physical parameters were measured and analyzed for groundwater samples collected in 2021 from twenty-six wells distributed throughout the investigation area. Overexploitation of groundwater caused considerable deterioration in the water quality, especially at Tajoura Town (20 Km east of Tripoli). The aquifer shows an increase in salinization, which has reached an alarming level in many places during the past 25 years as a result of the seawater intrusion. The chemical composition of the water samples was compared with the drinking water standards of WHO and Libyan Standards. Groundwater from this area was not suitable to be a source for direct drinking based on Total Dissolved Solids. The dominant cation is sodium, while the dominant anion is chloride. Based on the Piper trilinear diagram, most of the groundwater samples (90%) were identified as sodium chloride type. The best groundwater quality exists at the southern part of the study area. Serious degradation in the water quality, expressed in salinity increase, occurs as we go towards the coastline. The abundance of NaCl waters is strong evidence to attribute the successive deterioration of the water quality to the seawater intrusion. Considering the values of Cl- concentration and the ratio of Cl-/HCO3-, about 70% of the groundwater samples were strongly affected by the saline water. Car wash stations in the study area as well as the unlined disposal pond used for the collection of untreated wastewater, contribute significantly to the deterioration of water quality. The water quality in this area needs to be monitored regularly and it is crucial to treat the water before consumption.

Keywords: Tajoura, groundwater, seawater intrusion, water quality

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Authors: Harukuni Tokuda, Takanari Arai, Xu FengHao, Nobutaka Suzuki

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In our continuous search for anti-tumor promoting, chemopreventive active potency from natural source material, a kind of healthy tea, Gromwell seed (Coix lachryma-jobi) ext., and including compounds Monoolein and Trilinolein have been screened using the in vitro synergistic assay indicated by inhibitory effects on the induction of Epstein-Barr virus early antigen (EBV-EA) by TPA. In assay, Gromwell seed aqueous extract and hot aqueous extract exhibited the potential inhibitory effects on EBV-EA activation without strong cytotoxicity on Raji cells. In our experimental system, the inhibitory effects of both Gromwell extracts and compounds were greater than that of beta-carotene, which is known anti-tumor promoting agent and/or chemopreventive agent. These compounds were evaluated for their in vitro inhibitory effect on EBV-EA activation induced by TPA. The percentages of the inhibition of TPA-induced EBV-EA activation for these materials were 60% and 30% at concentration 100 μg. Based on the results obtained in vitro, we studied the inhibitory effect of compounds, in an in vivo two-stage carcinogenesis test of mouse skin papilloma using DMBA as an initiator and TPA as a potential promoter. The control animals showed a 100% incidence of papilloma at 20 weeks after DMBA-TPA tumor promotion, while treatment with compounds reduced the percentage of number of tumor to 60 % after 20 weeks. Results from in vitro and in vivo studies showing chemopreventive activity against TPA promoting stage and these data support the effective potency of carcinogenic stage in clinical evaluation of integrative oncology.

Keywords: gromwell seed, medicinal plant, chemoprevention, pharmaceutical medicine

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Authors: Arundhuti Devi, Gitumani Devi, Krishna G. Bhattacharyya

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The goal of this study was to assess the characteristics of the airborne dust created by opencast coal mining and its relation to population hospitalization risk for skin and lung diseases in Margherita Coalfield, Assam, India. Air samples were collected for 24 h in three 8-h periods. For the collection of particulate matter (PM10) and total suspended particulate matter (SPM) samples, respiratory dust samplers with glass microfiber filter papers were used. PM10 was analyzed for Cu, Cd, Cr, Mn, Zn, Ni, Fe and Pb with Flame Atomic Absorption Spectrophotometer (FAAS). SPM and PM10 concentrations were respectively found to be as high as 1,035 and 265.85 μg/m³ in work zone air. The concentration of metals associated with PM10 showed values higher than the permissible limits. It was observed that the average concentrations of the metals Fe, Pb, Ni, Zn, and Cu were very high during the winter month of December, those of Cd and Cr were high during the month of May and Mn was high during February. The morphology of the particles studied with scanning electron microscopy (SEM) gave significant results. Due to opencast coal mining, the air in the work zone, as well as the general ambient air, was found to be highly polluted with respect to dust. More than 8000 patient records maintained by the hospital authority were collected from three hospitals in the area. The highest percentage of people suffering from lung diseases are found in Margherita Civil Hospital (~26.77%) whereas most people suffering from skin diseases reported for treatment in the ESIC hospital (47.47%). Both PM10 and SPM were alarmingly high, and the results were in conformity with the high incidence of lung and other respiratory diseases in the study area.

Keywords: heavy metals, open cast coal mining, PM10, respiratory diseases

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Authors: Fabiha Tanzeem

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BACKGROUND: Osteoporosis is a skeletal disease that is associated with a reduction in bone mass and microstructures of the bone and deterioration of bone tissue. Fragility fracture due to osteoporosis is the most significant complication of osteoporosis. The increasing prevalence of fragility fractures presents a growing burden on the global economy. There is a rapidly evolving need to improve awareness of the costs associated with these types of fractures and to review current policies and practices for the prevention and management of the disease. This systematic review will identify and describe the direct and indirect costs associated with osteoporotic fragility fractures from a global perspective from the included studies. The review will also find out whether the costs required for the treatment of fragility fractures due to osteoporosis impose an economic burden on the global healthcare system. METHODS: Four major databases were systematically searched for direct and indirect costs of osteoporotic fragility fracture studies in the English Language. PubMed, Cochrane Library, Embase and Google Scholar were searched for suitable articles published between 1990 and July 2020. RESULTS: The original search yielded 1166 papers; from these, 27 articles were selected for this review according to the inclusion and exclusion criteria. In the 27 studies, the highest direct costs were associated with the treatment of pelvic fractures, with the majority of the expenditure due to hospitalization and surgical treatments. It is also observed that most of the articles are from developed countries. CONCLUSION: This review indicates the significance of the economic burden of osteoporosis globally, although more research needs to be done in developing countries. In the treatment of fragility fractures, direct costs were the main reported expenditure in this review. The healthcare costs incurred globally can be significantly reduced by implementing measures to effectively prevent the disease. Raising awareness in children and adults by improving the quality of the information available and standardising policies and planning of services requires further research.

Keywords: systematic review, osteoporosis, cost of illness

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Authors: G. Pelozo, N. Quaranta

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The assessment of environmental hazard and ecotoxicological potential of industrial wastes has become an issue of concern in many countries. Therefore, the aim of this work is to develop a methodology, adapting an Argentinian standard, which allows analyze the ecotoxicological effect of various metallurgical and steel wastes. Foundry sand, white mud, red mud, electric arc furnace dust, converter slag, among others, are the studied wastes. The species used to analyze the ecotoxicological effects of wastes is rye grass (Lolium Perenne). The choice of this kind lies, among other things, in its easy and rapid germination making it possible to develop the test in a few days. Moreover, since the processes involved are general for most seeds, the obtained results with this kind are representative, in general, of the effects on seeds or seedlings. Since the studied residues are solids, prior to performing the assay, an eluate is obtained by stirring for 2 hours and subsequent filtration of a solution of waste in water in a relationship of 1:4. This represents 100% of eluate from which two dilutions in water (25% and 50%) are prepared. A sample with untreated solid waste and water is also performed. The test is performed by placing two filter papers in a Petri dish that are saturated with 3.5ml of the prepared dilutions. After that 20 rye grass seeds are placed, and the Petri dishes are covered and the seeds are incubated for 120 hours at 24 °C. Reference controls are carried out by distilled water. Three replicates are performed for each concentration. Once the exposure period is finished, inhibiting elongation of the root is measured (IR). The results of this test show that all the studied wastes produce an unfavorable effect on the development of the seedlings, being the electric arc furnace dust which more affects the germination.

Keywords: ecotoxicity, industrial wastes, environmental hazard, seeds

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Authors: Anoff Anim, Lila A. M. Mahmoud, Maria Katsikogianni, Sanjit Nayak

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Sustained and controlled delivery of antimicrobial drugs have been largely studied recently using metal organic frameworks (MOFs)and different polymers. However, much attention has not been given to combining both MOFs and biodegradable polymers, which would be a good strategy in providing a sustained gradual release of the drugs. Herein, we report a comparative study of the sustained and controlled release of widely used antibacterial drugs, cephalexin and metronidazole, from zinc-based MOF-5 incorporated in biodegradable polycaprolactone (PCL) and poly-lactic glycolic acid (PLGA) membranes. Cephalexin and metronidazole were separately incorporated in MOF-5 post-synthetically, followed by their integration into biodegradable PLGA and PCL membranes. The pristine MOF-5 and the loaded MOFs were thoroughly characterized by FT-IR, SEM, TGA and PXRD. Drug release studies were carried out to assess the release rate of the drugs in PBS and distilled water for up to 48 hours using UV-Vis Spectroscopy. Four bacterial strains from both the Gram-positive and Gram-negative types, Staphylococus aureus, Staphylococuss epidermidis, Escherichia coli, Acinetobacter baumanii, were tested against the pristine MOF, pure drugs, loaded MOFs and the drug-loaded MOF-polymer composites. Metronidazole-loaded MOF-5 composite of PLGA (PLGA-Met@MOF-5) was found to show highest efficiency to inhibit the growth of S. epidermidis compared to the other bacteria strains while maintaining a sustained minimum inhibitory concentration (MIC). This study demonstrates that the combination of biodegradable MOF-polymer composites can provide an efficient platform for sustained and controlled release of antimicrobial drugs and can be a potential strategy to integrate them in biomedical devices.

Keywords: antimicrobial resistance, biodegradable polymers, cephalexin, drug release metronidazole, MOF-5, PCL, PLGA

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Authors: N. Allouache, W. Elgahri, A. Gahfif, M. Belmedani

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Solar radiation is by far the largest and the most world’s abundant, clean and permanent energy source. The amount of solar radiation intercepted by the Earth is much higher than annual global energy use. The energy available from the sun is greater than about 5200 times the global world’s need in 2006. In recent years, many promising technologies have been developed to harness the sun's energy. These technologies help in environmental protection, economizing energy, and sustainable development, which are the major issues of the world in the 21st century. One of these important technologies is the solar cooling systems that make use of either absorption or adsorption technologies. The solar adsorption cooling systems are a good alternative since they operate with environmentally benign refrigerants that are natural, free from CFCs, and therefore they have a zero ozone depleting potential (ODP). A numerical analysis of thermal and solar performances of an adsorption solar refrigerating system using different adsorbent/adsorbate pairs, such as activated carbon AC35 and activated carbon BPL/Ammoniac; is undertaken in this study. The modeling of the adsorption cooling machine requires the resolution of the equation describing the energy and mass transfer in the tubular adsorber, that is the most important component of the machine. The Wilson and Dubinin- Astakhov models of the solid-adsorbat equilibrium are used to calculate the adsorbed quantity. The porous medium is contained in the annular space, and the adsorber is heated by solar energy. Effect of key parameters on the adsorbed quantity and on the thermal and solar performances are analysed and discussed. The performances of the system that depends on the incident global irradiance during a whole day depends on the weather conditions: the condenser temperature and the evaporator temperature. The AC35/methanol pair is the best pair comparing to the BPL/Ammoniac in terms of system performances.

Keywords: activated carbon-methanol pair, activated carbon-ammoniac pair, adsorption, performance coefficients, numerical analysis, solar cooling system

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Authors: V. Kuzhandai Velu, R. Ramesh

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Background and objectives: Acute myocardial infarction (AMI) is the most common cause of mortality and morbidity. Over the last decade, microRNAs (miRs) have emerged as a potential marker for detecting AMI. The current study evaluates the kinetics and importance of miRs in the differential diagnosis of ST-segment elevated MI (STEMI) and non-STEMI (NSTEMI) and its correlation to conventional biomarkers and to predict the immediate outcome of AMI for arrhythmias and left ventricular (LV) dysfunction. Materials and Method: A total of 100 AMI patients were recruited for the study. Routine cardiac biomarker and miRNA levels were measured during diagnosis and serially at admission, 6, 12, 24, and 72hrs. The baseline biochemical parameters were analyzed. The expression of miRs was compared between STEMI and NSTEMI at different time intervals. Diagnostic utility of miR-1, miR-133, miR-208, and miR-499 levels were analyzed by using RT-PCR and with various diagnostics statistical tools like ROC, odds ratio, and likelihood ratio. Results: The miR-1, miR-133, and miR-499 showed peak concentration at 6 hours, whereas miR-208 showed high significant differences at all time intervals. miR-133 demonstrated the maximum area under the curve at different time intervals in the differential diagnosis of STEMI and NSTEMI which was followed by miR-499 and miR-208. Evaluation of miRs for predicting arrhythmia and LV dysfunction using admission sample demonstrated that miR-1 (OR = 8.64; LR = 1.76) and miR-208 (OR = 26.25; LR = 5.96) showed maximum odds ratio and likelihood respectively. Conclusion: Circulating miRNA showed a highly significant difference between STEMI and NSTEMI in AMI patients. The peak was much earlier than the conventional biomarkers. miR-133, miR-208, and miR-499 can be used in the differential diagnosis of STEMI and NSTEMI, whereas miR-1 and miR-208 could be used in the prediction of arrhythmia and LV dysfunction, respectively.

Keywords: myocardial infarction, cardiac biomarkers, microRNA, arrhythmia, left ventricular dysfunction

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Authors: André Jesus, Yanjie Zhu, Irwanda Laory

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Structural health monitoring is one of the most promising technologies concerning aversion of structural risk and economic savings. Analysts often have to deal with a considerable variety of uncertainties that arise during a monitoring process. Namely the widespread application of numerical models (model-based) is accompanied by a widespread concern about quantifying the uncertainties prevailing in their use. Some of these uncertainties are related with the deterministic nature of the model (code uncertainty) others with the variability of its inputs (parameter uncertainty) and the discrepancy between a model/experiment (systematic uncertainty). The actual process always exhibits a random behaviour (observation error) even when conditions are set identically (residual variation). Bayesian inference assumes that parameters of a model are random variables with an associated PDF, which can be inferred from experimental data. However in many Bayesian methods the determination of systematic uncertainty can be problematic. In this work systematic uncertainty is associated with a discrepancy function. The numerical model and discrepancy function are approximated by Gaussian processes (surrogate model). Finally, to avoid the computational burden of a fully Bayesian approach the parameters that characterise the Gaussian processes were estimated in a four stage process (modular Bayesian approach). The proposed methodology has been successfully applied on fields such as geoscience, biomedics, particle physics but never on the SHM context. This approach considerably reduces the computational burden; although the extent of the considered uncertainties is lower (second order effects are neglected). To successfully identify the considered uncertainties this formulation was extended to consider multiple responses. The efficiency of the algorithm has been tested on a small scale aluminium bridge structure, subjected to a thermal expansion due to infrared heaters. Comparison of its performance with responses measured at different points of the structure and associated degrees of identifiability is also carried out. A numerical FEM model of the structure was developed and the stiffness from its supports is considered as a parameter to calibrate. Results show that the modular Bayesian approach performed best when responses of the same type had the lowest spatial correlation. Based on previous literature, using different types of responses (strain, acceleration, and displacement) should also improve the identifiability problem. Uncertainties due to parametric variability, observation error, residual variability, code variability and systematic uncertainty were all recovered. For this example the algorithm performance was stable and considerably quicker than Bayesian methods that account for the full extent of uncertainties. Future research with real-life examples is required to fully access the advantages and limitations of the proposed methodology.

Keywords: bayesian, calibration, numerical model, system identification, systematic uncertainty, Gaussian process

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Authors: J. E. O. Hernandez

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In the next 20 years, energy production by burning fuels will increase and so will the atmospheric concentration of CO2 and its well-known threats to life on Earth. The technologies available for capturing CO2 are still dubious and this keeps fostering an interest in bio-inspired approaches. The leading one is the application of carbonic anhydrase (CA) –a superfast biocatalyst able to convert up to one million molecules of CO2 into carbonates in water. However, natural CA underperforms when applied to real smoky CO2 in chimneys and, so far, the efforts to create superior CAs in the lab rely on screening methods running under pristine conditions at the micro level, which are far from resembling those in chimneys. For the evolution of man-made enzymes, selection rather than screening would be ideal but this is challenging because of the need for a suitable artificial environment that is also sustainable for our society. Herein we present the stepwise design and construction of a bioprocess (from bench-scale to semi-pilot) for evolutionary selection experiments. In this bioprocess, reaction and adsorption took place simultaneously at atmospheric pressure in a spray tower. The scrubbing solution was fed countercurrently by reusing municipal pressure and it was mainly prepared with water, carbonic anhydrase and calcium chloride. This bioprocess allowed for the enzymatic carbonation of smoky CO2; the reuse of process water and the recovery of solid carbonates without cooling of smoke, pretreatments, solvent amines and compression of CO2. The average yield of solid carbonates was 0.54 g min-1 or 12-fold the amount produced in serum bottles at lab bench scale. This bioprocess could be used as a tailor-made environment for driving the selection of superior CAs. The bioprocess and its match CA could be sustainably used to reduce global warming by CO2 emissions from exhausts.

Keywords: biological carbon capture and sequestration, carbonic anhydrase, directed evolution, global warming

Procedia PDF Downloads 181

Authors: Manar Y. Abd El-Aziz, Alyaa E. Morgham, Amira A. El-Fallal, Heba Tolla E. Abo El Naga

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Different textile materials are usually used in upholstery. However, upholstery parts may become unhealthy when dust accrues and bacteria raise on the surface, which negatively affects the user's health. Also, leather and artificial leather were used in upholstery but, leather has a high cost and artificial leather has a potential chemical risk for users. Researchers have advanced vegie leather made from bacterial cellulose a symbiotic culture of bacteria and yeast (SCOBY). SCOBY remains a gelatinous, cellulose biofilm discovered floating at the air-liquid interface of the container. But this leather still needs some enhancement for its mechanical properties. This study aimed to prepare SCOBY, produce bamboo rib knitted fabrics with two different stitch densities, and cotton woven fabric then laminate these fabrics with the prepared SCOBY film to enhance the mechanical properties of the SCOBY leather at the same time; add anti-microbial function to the prepared fabrics. Laboratory tests were conducted on the produced samples, including tests for function properties; anti-microbial, thermal conductivity and light transparency. Physical properties; thickness and mass per unit. Mechanical properties; elongation, tensile strength, young modulus, and peel force. The results showed that the type of the fabric affected significantly SCOBY properties. According to the test results, the bamboo knitted fabric with higher stitch density laminated with SCOBY was chosen for its tensile strength and elongation as the upholstery of a bed model with antimicrobial properties and comfortability in the headrest design. Also, the single layer of SCOBY was chosen regarding light transparency and lower thermal conductivity for the creation of a lighting unit built into the bed headboard.

Keywords: anti-microbial, bamboo, rib, SCOPY, upholstery

Procedia PDF Downloads 49

Authors: Guanghua Lu, Zhenhua Yan

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To investigate the estrogenic contamination and potential risk of Taihu Lake, eight active biomonitoring points in the northern section of Taihu Lake were set up and located in Wangyuhe River outlet (P1), Gonghu Bay (P2 and P3), Meiliang Bay (P4 and P5), Zhushan Bay (P6 and P7) and Lake Centre (P8). A suite of biomarkers in caged fish after in situ exposure for 28 days, coupled with six selected exogenous estrogens in water, were determined in May and December 2011. Six target estrogens, namely estrone (E1), 17b-estradiol (E2), ethinylestradiol (EE2), estriol (E3), diethylstilbestrol (DES) and bisphenol A (BPA), were quantified using UPLC/MS/MS. The concentrations of E1, E2, E3, EE2, DES and BPA ranged from ND to 3.61 ng/L, ND to 17.3 ng/L, ND to 1.65 ng/L, ND to 10.2 ng/L, ND to 34.6 ng/L, and 3.95 to 207 ng/L, respectively. BPA was detected at all sampling points at all test periods, E2 was detected at 95% of samples, E1 and EE2 was detected at 75% of samples, and E3 was detected only in December 2011 with quite low concentrations. Each individual estrogen concentration measured at each sampling point was multiplied by its relative potency to gain the estradiol equivalent (EEQ). The total EEQ values in all the monitoring points ranged from 5.69 to 17.8 ng/L in May 2011, and from 4.46 to 21.1 ng/L in December 2011. E2 and EE2 were thought to be the major causal agents responsible for the estrogenic activities. Serum vitellogenin and E2 levels, gonadal DNA damage, and gonadosomatic index were measured in the in situ exposed fish. An enhanced integrated biomarker response (EIBR) was calculated and used to evaluate potential feminization risk of fish in the polluted area of Taihu Lake. EIBR index showed good agreement with the observed total EEQ levels in water. Our results indicated that Gong bay and the lake center had a low estrogenic risk, whereas Wangyuhe River, Meiliang Bay, and Zhushan Bay might present a higher risk to fish.

Keywords: active biomonitoring, estrogen, feminization risk, Taihu Lake

Procedia PDF Downloads 266

Authors: Vinh Duy Cao, Shima Pilehvar, Anna M. Szczotok, Anna-Lena Kjøniksen

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The total energy consumption is dramatically increasing on over the world, especially for building energy consumption where a significant proportion of energy is used for heating and cooling purposes. One of the solutions to reduce the energy consumption for the building is to improve construction techniques and enhance material technology. Recently, microcapsulated phase change materials (MPCM) with high energy storage capacity within the phase transition temperature of the materials is a potential method to conserve and save energy. A new composite materials with high energy storage capacity by mixing MPCM into concrete for passive building technology is the promising candidate to reduce the energy consumption. One of the most untilized building materials for mixing with MPCM is Portland cement concrete. However, the emission of carbon dioxide (CO2) due to producing cement which plays the important role in the global warming is the main drawback of PCC. Accordingly, an environmentally friendly building material, geopolymer, which is synthesized by the reaction between the industrial waste material (aluminosilicate) and a strong alkali activator, is a potential materials to mixing with MPCM. Especially, the effect of MPCM on the thermal and mechanical properties of geopolymer concrete (GPC) is very limited. In this study, high thermal energy storage capacity materials were fabricated by mixing MPCM into geopolymer concrete. This article would investigate the effect of MPCM concentration on thermal and mechanical properties of GPC. The target is to balance the effect of MPCM on improving the thermal performance and maintaining the compressive strength of the geopolymer concrete at an acceptable level for building application.

Keywords: microencapsulated phase change materials, geopolymer concrete, energy storage capacity, thermal performance

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Authors: Hong-Min Kim, Da-Som Han, Myong-Hoon Lee

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CLCs (Cholesteric liquid crystals) draw tremendous interest due to their potential in various applications such as cholesteric color filters in LCD devices. CLC possesses helical molecular orientation which is induced by a chiral dopant molecules mixed with nematic liquid crystals. The efficiency of a chiral dopant is quantified by the HTP (helical twisting power). In this work, we designed and synthesized a series of new chiral dopants having a Schiff’s base imine structure with different alkyl chain lengths (butyl, hexyl and octyl) from chiral naphthyl amine by two-step reaction. The structures of new chiral dopants were confirmed by 1H-NMR and IR spectroscopy. The properties were investigated by DSC (differential scanning calorimetry calorimetry), POM (polarized optical microscopy) and UV-Vis spectrophotometer. These solid state chiral dopants showed excellent solubility in nematic LC (MLC-6845-000) higher than 17wt%. We prepared the CLC(Cholesteric Liquid Crystal) cell by mixing nematic LC (MLC-6845-000) with different concentrations of chiral dopants and injecting into the sandwich cell of 5μm cell gap with antiparallel alignment. The cholesteric liquid crystal phase was confirmed from POM, in which all the samples showed planar phase, a typical phase of the cholesteric liquid crystals. The HTP (helical twisting power) is one of the most important properties of CLC. We measured the HTP values from the UV-Vis transmittance spectra of CLC cells with varies chiral dopant concentration. The HTP values with different alkyl chains are as follows: butyl chiral dopant=29.8μm-1; hexyl chiral dopant= 31.8μm-1; octyl chiral dopant=27.7μm-1. We obtained the red, green and blue reflection color from CLC cells, which can be used as color filters in LCDs applications.

Keywords: cholesteric liquid crystal, color filter, display, HTP

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Authors: Seong Woon Lee, Soo Min Lim, Sung Sik Jeong, Jung Hoon Park

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The atmospheric concentration of greenhouse gas (GHG, Green House Gas) is increasing continuously as a result of the combustion of fossil fuels and industrial development. In response to this trend, many researches have been conducted on the reduction of GHG. Landfill gas (LFG, Land Fill Gas) is one of largest sources of GHG emissions containing the methane (CH₄) as a major constituent and can be considered renewable energy sources as well. In order to use LFG by connecting to the city pipe network, it required a process for removing impurities. In particular, oxygen must be removed because it can cause corrosion of pipes and engines. In this study, methane oxidation was used to eliminate oxygen from LFG and perovskite-type ceramic catalysts of La-Sr-Co-Fe-O composition was selected as a catalyst. Hollow fiber catalysts (HFC, Hollow Fiber Catalysts) have attracted attention as a new concept alternative because they have high specific surface area and mechanical strength compared to other types of catalysts. HFC was prepared by a phase-inversion/sintering technique using commercial La-Sr-Co-Fe-O powder. In order to measure the catalysts' activity, simulated LFG was used for feed gas and complete oxidation reaction of methane was confirmed. Pore structure of the HFC was confirmed by SEM image and perovskite structure of single phase was analyzed by XRD. In addition, TPR analysis was performed to verify the oxygen adsorption mechanism of the HFC. Acknowledgement—The project is supported by the ‘Global Top Environment R&D Program’ in the ‘R&D Center for reduction of Non-CO₂ Greenhouse gases’ (Development and demonstration of oxygen removal technology of landfill gas) funded by Korea Ministry of Environment (ME).

Keywords: complete oxidation, greenhouse gas, hollow fiber catalyst, land fill gas, oxygen removal, perovskite catalyst

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Authors: Boularas El Alia, H. Rezk-Allah, S. Chaoui, A. Chama, B. Rezk-Allah

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Aims: To assess the current exposure to the PHA among various workers in the sector of asphalt and road paving. Methods: The assessment of the exposure to PHA has been performed on workers (n=14) belonging to two companies, allocated into several activities such as road paving, manufacturing of coated bituminous warm, manufacturing of asphalt cut-back, manufacturing of emulsion of asphalt. A group of control subjects (n=18) was associated. The internal exposure to PHA was investigated by measurement of the urinary excretion of 2-naphtol, urine metabolite of naphtalene, one of the biomarkers of total PHA exposure. Urine samples were collected from the exposed workers, at the beginning of the week, at the beginning of the work shift (BWBS) and at the end of the work shift, at the end of the week (ESEW). In the control subjects, single samples of urine were collected after the end of the work shift.Every subject was invited to answer a questionnaire for the collection of technical and medical data as well as smoking habits and food intake. The concentration of 2-naphtol in the hydrolysate of urine was determined spectrophotometrically, after its reaction with the Fast Blue BB salt (diazotized 4-benzoylamino-2,5-diethoxyaniline). Results: For all the workers included in the study, the 2-urinary naphtol concentrations were higher than those in the control subjects (Median=9,55 µg/g creatinine) whether it is at (BWBS) (Md=16,2 µg/g creatinine) or at (ESEW) (n=18,Median=32,22 µg/g creatinine). Considerable differences are observed according to the category of job. The concentrations are also higher among smokers. Conclusion:The results show a significant exposure, mainly during manual laying, reveals an important risk particularly for the respiratory system.Considering the current criteria, carcinogenic risk due to the PHA seems not insignificant.

Keywords: PHA, asphalt, assessment, occupational, exposure

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Authors: Manpreet Kaur, Badaruddoza, Sandeep Kaur Brar

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The increasing prevalence of adolescent obesity is one of the major causes to be hypertensive in adulthood. Various statistical methods have been applied to examine the performance of anthropometric indices for the identification of adverse cardiovascular risk profile. The present work was undertaken to determine the significant traditional risk factors through principal component factor analysis (PCFA) among population based Punjabi adolescents aged 10-18 years. Data was collected among adolescent children from different schools situated in urban areas of Punjab, India. Principal component factor analysis (PCFA) was applied to extract orthogonal components from anthropometric and physiometric variables. Association between components were explained by factor loadings. The PCFA extracted four factors, which explained 84.21%, 84.06% and 83.15% of the total variance of the 14 original quantitative traits among boys, girls and combined subjects respectively. Factor 1 has high loading of the traits that reflect adiposity such as waist circumference, BMI and skinfolds among both sexes. However, waist circumference and body mass index are the indicator of abdominal obesity which increases the risk of cardiovascular diseases. The loadings of these two traits have found maximum in girls adolescents (WC=0.924; BMI=0.905). Therefore, factor 1 is the strong indicator of atherosclerosis in adolescents. Factor 2 is predominantly loaded with blood pressures and related traits (SBP, DBP, MBP and pulse rate) which reflect the risk of essential hypertension in adolescent girls and combined subjects, whereas, factor 2 loaded with obesity related traits in boys (weight and hip circumferences). Comparably, factor 3 is loaded with blood pressures in boys and with height and WHR in girls, while factor 4 contains high loading of pulse pressure among boys, girls and combined group of adolescents.

Keywords: adolescent obesity, cvd, hypertension, punjabi population

Procedia PDF Downloads 359