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There is a major political commitment at the European Union level to providing good quality sexuality education in schools. Multiple studies in the World Health Organization (WHO) European Region have demonstrated the importance of sexuality education for the health and well-being of children and adolescents. Parents’ role in providing information about sex, sexuality and relationships has also been widely recognised, though we know little about the involvement of parents in school-based sexuality education and the possible outcomes. We conducted a scoping review to systematically identify initiatives within the WHO European Region that involve parents in school-based sexuality education. We identified five programmes – four of which had been implemented in the UK and one in Turkey. In addition, online expert consultations provided professional insights and resources related to the topic. This review indicates that initiatives to involve parents in school-based SE exist within the region. Although our results refer to the benefits of involving parents in school-based sexuality education, such as improving communication between parents and children and contributing to parental trust in a school’s approach to sexuality education, it also indicates barriers, for example, lack of time on the part of parents and teachers. [ABSTRACT FROM AUTHOR]

Thermal stress assessment inside steam reactor to prevent future damage is necessary due to the high temperatures of the hot gases used for endothermic reactions. This study combined solid mechanics equations, mass, energy, and fluid flow to develop a model could describe the thermal stress and deformation inside hydrocarbon-steam reactors. The model results were validated and compared to experimental results over a range of operating temperatures with an error of less than 2%. The results show that the temperature of the inlet gas in the reactor bed decreases in the early stages of the reactor, then increases later causing simultaneous gas velocity increase proportional with the temperature. The study shows that both hot gases temperature and gas velocity could control endothermic reactions rates. Where, at T = 900 K of inlet hot gases, full propane consumption is achieved at the reformer outlet and the velocity could reach twice that of the inlet. Furthermore, at a certain temperature, the non-uniform thermal stress distribution within the steam-propane reformer unit can cause deflections, which lead to cracks. [Display omitted] • The thermal stress inside steam reactors was described by a novel model. • The study combined solid mechanics equations with mass, energy, and fluid flow. • Inlet gas velocity inside reactor increase proportionally coincide with temperature. • Both temperature and velocity of hot gases can affect endothermic reactions. • In a certain temperature range, thermal stress causes cracks inside a reactor. [ABSTRACT FROM AUTHOR]

Objective: Pelvic organ prolapse (POP) is a common condition. With increasing lifespan and emphasis on quality of life worldwide, older women with POP may prefer surgical treatment, including colpocleisis. We reviewed the outcome of POP in a case series of colpocleisis. Methods: This study was conducted between 2006 and 2011. Patients had confirmed POP on examination and underwent partial and total colpocleisis. We compared patients’ demographic characteristics, POP severity and surgical outcomes. Results: In total, 55 patients were included. The patients were aged 78.9 + 6.7 years and had body mass index (BMI) of 26.9 ± 4.2. Among the total, 44 (80%) and 11 patients (20%) underwent partial and total colpocleisis respectively. Patients undergoing partial colpocleisis had procidentia less often than those undergoing total colpocleisis (18% v 64%, p=0.01). Mean blood loss and operative time were 157.6 ml ± 119.0 and 65.1 ± 20.3 minutes respectively. Partial colpocleisis had less blood loss (mean 135.7 v 227.2 ml, p=0.02) and shorter operative time (mean 62.6 v 75.0 min, p=0.18). Conclusion: Partial compared to total colpocleisis was associated with shorter operative time and less blood loss. Colpocleisis is a suitable surgical treatment for POP in elderly women who do not wish to preserve the vagina for sexual intercourse. [ABSTRACT FROM AUTHOR]

Recently, the oscillators and hidden attractors have become so important in many fields, like biomedical, electrical and electronics engineering applications. Chaos can be exhibited mathematically by systems of nonlinear differential equations which is recognized widely. This paper investigates a three-dimensional autonomous oscillator with sinusoidal nonlinearities in each dimension of the proposed oscillator model. Such nonlinearities maximize the chaotification properties of such a model and therefore increase complexity performance accordingly. We show 2D-bifurcation diagram with new hidden attractor. It shows that the proposed oscillator can produce a variety of dynamical behaviors, including limit cycle, torus, and strange attractor. Our goal is to find chaotic attractor. [ABSTRACT FROM AUTHOR]

Polymer electrolyte membrane (PEM) fuel cells are promising eco-friendly and sustainable power generation technology. Thermal management of these cells is one of the main challenges facing their commercialization. Alumina nanofluids, in addition to others, have been proposed to overcome excess heat generated within the PEM fuel cell stacks. However, most the previous studies investigated the hydrothermal performance of the nanofluids as a function of Reynolds number (Re). It is evident that all parameters must be kept constants except one to examine its effect on the performance. To this end, choosing Re as a parameter (independent variable) is problematic as it is a function not only of nanofluid's velocity, but also its density and viscosity. In this study, a well-validated CFD model has been built to simulate the hydrothermal performance of alumina nanofluids of different volumetric concentrations (0%, 0.05%, 0.1% and 0.2%) as functions of Re (170 < Re < 530), flow rate (20 ml/min ≤ V f ≤ 50 ml/min), and pumping power (0.025 mW < Pp < 0.3 mW). This study shows a maximum reduction of 7.9% in the thermal effectiveness and a maximum increase of 6% in the pumping power when using the nanofluids instead of water. This deterioration in the hydrothermal performance is due to the reduction in the effective specific heat capacity and increase in viscosity of the nanofluids. Also, it is concluded that it is incorrect to use Re as an independent variable in analysing the hydrothermal performance of nanofluids because of the dependency of Re on some of the thermophysical properties of the nanofluids, which are functions of the concentration. Adopting such analysing procedure leads to false conclusions. [Display omitted] • Al 2 O 3 –H 2 O nanofluids are prepared and characterised and a CFD model is built. • Hydrothermal performance of the nanofluids is evaluated. • New evaluation methods – effectiveness (ε) and pumping cost (Pc) – are developed. • Using Re for thermal analysis is misleading while ε and Pc are more appropriate. • Hydrothermal performance of water is better than Al 2 O 3 – H 2 O coolants. [ABSTRACT FROM AUTHOR]

The nanostructured SnS thin films were obtained by a low-cost chemical spray pyrolysis method (CSP). The optical and structural parameters of SnS nano films were studied by different thickness. X-ray diffraction showed that films were of orthorhombic structure with preferred orientation in the (111) direction. These films reveal a decrease in crystallite due to thickness film increasing. Results indicated that films showed < 70% of transparency in visible region. The same behavior was noticed for the optical bandgap. Results obtained by dispersion parameters mention thickness dependency. [ABSTRACT FROM AUTHOR]

The work of solar cells and their production of electrical energy have been affected by climate change, especially in hot regions which became significantly hotter and still receive relatively high levels of solar radiation throughout the year. Higher ambient temperature and solar radiation result in higher PV cell temperature and, therefore, the reduction in PV module power output and efficiency. This study investigates how a PV module performs throughout the year in a hot region by considering the variations in cell temperature resulting from changes in ambient temperature and solar radiation every day. The tilt angles and two-axis tracking have also been examined. Results indicate that the two-axis solar tracking system is critical to use in hot regions for obtaining higher output power. Therefore, part of this power can be used to cool solar panels using various methods to keep their efficiency high, such as operating air fans or operating pumps to cool them with coolant. [ABSTRACT FROM AUTHOR]

Recently, location-based social networks, that involve both social and spatial information, have received much attention in many real-world applications such as location-based services (LBS), map utilities, business planning, and so on. In this paper, we seamlessly integrate both social networks and spatial road networks, resulting in a so-called spatial-social network, and study an important and novel query type, named group planning query over spatial-social networks (GP-SSN), which is very useful for applications such as trip recommendations. In particular, a GP-SSN query retrieves a group of friends with common interests on social networks and a number of spatially close points of interest (POIs) on spatial road networks that best match group’s preferences and have the smallest traveling distances to the group. In order to tackle the GP-SSN problem, we design effective pruning methods, matching score pruning, user pruning, and distance pruning, to rule out false alarms of GP-SSN query answers and reduce the problem search space. We also propose effective indexing mechanisms to facilitate the GP-SSN query processing, and develop efficient GP-SSN query answering algorithms via index traversals. Extensive experiments have been conducted to evaluate the efficiency and effectiveness of our proposed GP-SSN query processing approaches. [ABSTRACT FROM AUTHOR]

The nanostructured SnS thin films were obtained by a low-cost chemical spray pyrolysis method (CSP). The optical and structural parameters of SnS nano films were studied by different thickness. X-ray diffraction showed that films were of orthorhombic structure with preferred orientation in the (111) direction. These films reveal a decrease in crystallite due to thickness film increasing. Results indicated that films showed < 70% of transparency in visible region. The same behavior was noticed for the optical bandgap. Results obtained by dispersion parameters mention thickness dependency. [ABSTRACT FROM AUTHOR]

Objective: This study examined gynaecologists' experience and views on the management of vaginal vault prolapse (VVP) using laproscopic sarcocolpopexy (LSCP) versus open sarcocolpopexy (OSCP). Methods: In a qualitative study conducted at the University of Surrey and Homerton University Hospital, UK, from 2016 to 2017, semi-structured interviews were conducted with 15 consultants experienced in minimal access surgery or urogynecology. Interviews were recorded and transcripts were analyzed using the qualitative description (QD) approach. Results: Eight broad themes emerged: VVP management, LSCP for management of VVP, OSCP and vaginal surgery with or without mesh use in VVP management, laparoscopic training and support as well as surgeons' attitude towards LSCP. All participants acknowledged the importance of LSCP in the management of posthysterectomy VVP as benefits outweighed risks in their view. OSCP was considered suitable in very specific circumstances. Vaginal surgery could be an excellent alternative to OSCP bearing in mind long-term efficacy and sexual activity in young women. Most participants agreed with national recommendations to avoid use of mesh in vaginal surgery for VVP and expressed the view that it should be done in specialised centres by trained surgeons who do such operations. Conclusions: This study showed that the acceptability of LSCP was dependent on participants' experience and consideration of the balance between patient's goals and potential risks. It provides useful guidance for future large-scale projects. [ABSTRACT FROM AUTHOR]

In this paper, the topography properties as layer thickness, porosity, and shape are studied for porous silicon prepared by using electro‐chemical etching method from p‐type bulk silicon like one side mirror with hydrofluoric acid (39%–43%) and ethanol (99.9%) (2:1), the etching time is (2, 4, 6, 8, and 10) min, with potential (6 V DC), the porosity and layer thickness can determine by using gravimetric method and SEM image to study the comparison between the image for different etching time. [ABSTRACT FROM AUTHOR]

Replacing fossil fuels with hydrogen helps us cut our carbon footprint and turn into green transportation. Hydrogen is an essential fuel for our secure and clean energy future. Hydrogen will be the future fuel, and gradually it will replace all current fossil fuels. The present work provides an overview of combating climate change with hydrogen as an alternative fuel for transportation, which can be used in internal combustion engines and fuel cells [ABSTRACT FROM AUTHOR]

Background: Colonization of human nose by Staphylococcus aureus represent up to 30% of the human population. S. aureus must defeats the host's defense mechanisms in order to colonize the nasal epithelial cells of human. Some factors such as bacterial interaction in human nose can prevent such colonization. Aim: The aim of current study was to determine the prevalence of nasal colonization by S. aureus among the staff and students of University of Science & Technology, Aden; as well as the associated risk factors for nasal carriage. Subjects and Methods: The type of study was an institution-based cross-sectional study which performed during the period from January to March 2020. The total samples were 1030 nasal swabs obtained from all the staff and students, the specimens were transported to the laboratory and the swabs were processed within 4 hrs. of collection. Results: The mean age of the study sample was 21.4 (±5.8 SD). The prevalence S. aureus isolated from nasal carriages was 31%. S. aureus nasal carriage show high frequency among age group 27-36 (32.4%) followed by those at age of 17-26 years (31%), however, there was no a statistically significant association in relation to the age groups (P=0.9). Regarding gender, it was considered a risk factor. S. aureus more common in male than female. The pattern of sleep, smoking, and frequent touching the nose were statistically associated with the S. aureus nasal colonization. Those who had nasal sensitivity was considered risk factor (RR=1.3) but with non-significant association with S. aureus nasal colonization (P=0.4). Conclusion: The current study revealed that community acquired was the potential colonizers of S. aureus. With the prevalence of 31% of the study sample, age, gender, and smoking, and other were potential risks. Regular screening of carriers is required for prevention of community acquired infections. [ABSTRACT FROM AUTHOR]

The performance of photovoltaic cells is affected by the cell's temperature resulting from the ambient temperature. The solar cell's efficiency decreases significantly in hot regions due to its high temperature. In this work, the effect of cell temperature on the performance and efficiency of a photovoltaic cell consists of three layers is studied using a three-dimensional CFD model. A serpentine circular pipe has been fixed behind the aluminium plate and used as a heat exchanger to transfer the heat from the photovoltaic cell to the pipe fluid and reduces the photovoltaic cell temperature. Alumina nanoparticles (Al2O3) has been chosen due to the good chemical stability in the base fluid (water), relatively low cost compared to other nanoparticles, and most importantly, a lot of literature concluded that using Al2O3 nanofluid can improve the heat transfer in heat exchangers. Nanoparticles of Al2O3 were added to the water at a rate of 4% to improve the thermal performance and efficiency of the heat exchange. The results showed an improvement of approximately 10% in the photovoltaic electrical efficiency when using the water cooling method and about 12% when using the nanofluid. The importance of the results in this study illustrates the possibility of increasing the performance and efficiency of the photovoltaic cell by cooling it in hot environment conditions with water alone and also with nanofluids by using a small percentage of nanoparticles. [ABSTRACT FROM AUTHOR]

The energy crisis and pollution are vital issues today, which have led to researchers investigating nonpetroleum, renewable, sustainable, and non-polluting fuels to reduce fuel consumption and reduce toxic compounds in combustion products. Hydrogen and methanol can be alternatives to conventional energy sources such as natural gas, oil, and coal since they can be coupled with renewable and sustainable sources. The purpose of this study is to investigate the engine performance and pollutant emission of a spark ignition engine using hydrogen-methanol blended fuels with various blended rates for hydrogen (0%, 2%, 4%, 6%, 8%, 10% 12% by mass). The usage of hydrogen as supplementary fuel to the methanol-air mixture for spark ignition engine results in considerable improvement of the engine performance and in the reduction of the toxic components in the exhaust gases in comparison with the conventional spark ignition gasoline engine. The important improvement of hydrogen addition is to reduce the s.f.c and CO emission of methanol engines. The Possibility of the engine power quality adjustment has also been studied. [ABSTRACT FROM AUTHOR]

To colonize and infect the host, arthroconidial yeasts must avoid being killed by the host's defenses. The formation of biofilms on implanted devices allows fungi to avoid host responses and to disseminate into the host. To better study the mechanisms of infection by arthroconidial yeasts, adherence and biofilm formation were assayed using patient samples collected over 10 years. In clinical samples, adherence varies within species, but the relative adherence is constant for those samples isolated from the same infection site. Herein we document, for the first time, in-vitro biofilm formation by Trichosporon dohaense, T. ovoides, T. japonicum, T. coremiiforme, Cutaneotrichosporon mucoides, Cutaneotrichosporon cutaneum, Galactomyces candidus, and Magnusiomyces capitatus on clinically relevant catheter material. Analysis of biofilm biomass assays indicated that biofilm mass changes less than 2-fold, regardless of the species. Our results support the hypothesis that most pathogenic fungi can form biofilms, and that biofilm formation is a source of systemic infections. [ABSTRACT FROM AUTHOR]

Droplets and aerosolized viral particles expelling from the body through coughing or sneezing and it is spreading to nearby surroundings. Two-phases, three-dimensional, Computational Fluid Dynamics (CFD) model using Reynolds Average Navier Stokes (RANS) equations has been developed to simulate the air flow and the transport and dispersion of the aerosolized viral particles and fine droplets suspended in the air particles through the office. The study presents two cases involving the spreading limits and pathways of the aerosolized viral particles and fine droplets suspended in the air in a place; without and with air conditioning unit. The results showed that the use of air conditioning systems can increase the chances of spreading COVID-19 virus infection. The air-conditioning unit recirculates the same air inside a room, and this has the potential to create a virus-laden environment. Air circulation indoors such as using air conditioning units should be avoided in closed places. Existing ventilation systems should be expanded to include extraction and air filtration systems and/or germicidal, ultraviolet light. Also, opening a window can help bring in fresh air from the outside and disperse stale air inside, and that could help reduce the possibility of the spread of the virus particles in the closed place. Lastly, crowds of people in closed public places should be avoided. This work is beneficial for the ventilation strategy design for mitigating COVID-19. [ABSTRACT FROM AUTHOR]

The University of Technology in Baghdad addresses problems related to the corrosion of metals. In the present investigation, a thiophene derivative, namely, 2-acetylthiophene thiosemicarbazone (2-AT), was synthesized and examined as a corrosion inhibitor for mild steel in a 1-M hydrochloric acid environment by using weight loss and scanning electron microscopic techniques. The inhibition efficiency of this inhibitor increases with increase in concentration, which offered an inhibition efficiency up to 96%. It was found that the inhibition efficiency decreases with long immersion time. The temperature effect on the inhibition performance was studied at various immersion times and revealed that the inhibition efficiency decreases with increasing temperature. The adsorption of the inhibitor on the surface of mild steel in the corrosive environment followed the Langmuir isotherm. The results of scanning electron microscopy (SEM) reveal that the 2-AT molecules confirmed the presence of a protective layer on the surface of a mild steel sample. The density-functional theory as a quantum modeling technique which is used to study the electronic structure reveals that the obtained findings were found to be consistent with the experimental results. [ABSTRACT FROM AUTHOR]

The viscosity and flow rate as rheological characteristics are fundamental in evaluating the nanofillers in processing the polyethylene-nanotube (PE-NT) composite in injecting molding. The purpose of this investigation is to study the rheological conduct of PE-NT composite plastic feedstock through capillary rheometry. For the purpose of obtaining a flawless component, the feedstock is used as a critical parameter, and care must be taken while introducing the raw materials with high solid load and hence perfect flowability. The shear rate viscosity of different feedstocks at an NT ratio extending at 0–3 wt.% has been determined at L/D equal to 10 die and a load extending at 40.0–80.0 KGF at temperatures 140.0, 150.0 and 160.0°C. The three specimens' viscosity was measured in order to exhibit that the corresponding flow conduct factor varies from 0.40 to 0.70, demonstrating the non-Newtonian behavior of the specimens. The three specimens' activation energies at the studied temperature degrees were evaluated and turned out to be 36.5–69.88 kJ/mol according to the applied load. [ABSTRACT FROM AUTHOR]

Hydrogen is a very important fuel of our secure and clean energy future. Hydrogen will be the fuel of the future and gradually it will replace all current fossil fuels. Hydrogen can be used as a fuel for vehicles, to heat homes and offices, to produce electricity, and to fuel ships and aircraft. The present work provides an overview of hydrogen as an alternative fuel, which can be used in internal combustion engines and in fuel cells. [ABSTRACT FROM AUTHOR]

A human arm makes many functions that a robotic arm always programmed to make same functions. The human limbs motion can be captured using sensors that they will always copy hand movement. The rapid spread of the Coronavirus (COVID-19) virus and contacting the infections make the number of patients doubled in short time. The system proposed in this research can protect clinicians against infection with virus by reducing the contact with the infected and treat them remotely. This system type can be useful in different other fields of industrial works and defense where dangerous and delicate task can be done remotely without actual touch. Xbee shield is used to allow a hand glove flex sensor to communicate with the robotic arm using Zigbee wirelessly. Zigbee here is based on Xbee module from Max stream that can be communicate outdoor for 300 feet with the line of sight and indoor for 100 feet. Proportional, integral and derivative (PID) controller used in the proposed system to achieve smooth movement of limbs. The desired signal comes from flex sensor that connected to each limb. Kalman estimator proposed to find current state of each limb. In order to get better performance, particle swarm optimization (PSO) is used. [ABSTRACT FROM AUTHOR]

Thermal management is essential in electronics, as it improves reliability and enhances performance by removing heat generated by the devices. Thermal management of handheld systems such as laptops is becoming increasingly challenging due to increasing power dissipation. The power dissipated per unit area on the laptop electronic chips is increasing while the area of the chips itself it decreasing, resulting a high heat flux that causes an increase in temperature. The increasing temperature adversely affects the performance of laptops and in many cases leads to failure through such modes as thermal fatigue and dielectric breakdown. In this work, three dimensional steady state CFD model of a laptop motherboard is presented. The model accounts for heat transfer for both natural convection and radiation to the ambient air temperature. The present CFD study allow accurate, rapid, physical modelling to make decisions on materials, components and layout beside power control feedback to achieve performance and target lifetime with reduced testing requirements. An alternative design for the cooling of laptop microprocessor using only passive cooling is proposed. The results showed that the assembled a thin plate of a copper material coated with graphene and use it as a heat sinks with the microprocessor of the laptop providing an efficient and economical solution in thermal management. Considerable drop in microprocessor temperature is obtained through the heat dissipation path suggested in the new design. The proposed passive cooling solution has the advantages of fanless operation compared to the existing active cooling solutions such as the noise-free operation, lower energy consumption and higher reliability. We hope this work may open the way for huge boost in the technology of electric cooling by innovative manufacturing techniques. [ABSTRACT FROM AUTHOR]

The present paper present a study on the influence of polymer density on fiber formation by different polymers when using the electro-hydrodynamic (EHD) process. Parameters, such as the internal pressure, radius of fibers and the viscosity force were determined in function of the distance between electrodes. The studies were done for different polymer densities (0.481, 0.529, 0.609, 0.705, 0.9249) g/cm3. It was found that it is an important parameter influencing internal polymer pressure, diameter of produced nanofibers. The polymer density impacts also on the viscosity force. All these parameter: internal polymer pressure, radius of nanofibers depend on the distance between the electrodes. [ABSTRACT FROM AUTHOR]

Thermal management is essential in electronics, as it improves reliability and enhances performance by removing heat generated by the devices. Maintaining safe chip and device skin temperatures in small form-factor mobile devices (such as smartphones) while continuing to add new functionalities and provide higher performance has emerged as a key challenge. A significant increase in reliability and smartphones life can be achieved by a small reduction in operating temperature. With the limitations of space and power, radiation and natural convection plays an important role in heat removal mechanisms in smartphones engineering designs. A case study on an iPhon5 using CFD is provided to relate the device performance to the skin temperature and investigate the thermal path design. Three dimensional CFD model of an iPhone5 has been presented. The model accounts for heat transfer for conduction through the phone components materials and for both natural convection and radiation to the ambient air temperature. The comparison between the CFD simulation and the thermal image obtained by the thermal camera shows some similarities like, for example, hot-spots located in the same places. The present CFD study allow accurate, rapid, physical modelling to make decisions on materials, components and layout beside power control feedback to achieve performance and target lifetime with reduced testing requirements. Parametric study considered operating time, ambient temperatures, and materials to investigate the impact of each on the temperature distribution in smartphones has been presented. [ABSTRACT FROM AUTHOR]

PURPOSE: The Targeted Agent and Profiling Utilization Registry (TAPUR) Study identifies signals of antitumor activity of commercially available targeted agents in patients with advanced cancers that harbor genomic alterations known as drug targets. In this article, data from two cohorts of patients with pancreatic and biliary cancers with CDKN2A loss or mutation treated with palbociclib are reported. METHODS: Eligible patients age 12 years and older with advanced measurable or evaluable solid tumors are provided treatment according to protocol-specified genomic matching rules. The primary study end point is objective response or stable disease of at least 16 weeks duration. For each cohort, a Simon two-stage design was used with a futility evaluation after 10 patients. Secondary end points include safety, progression-free survival (PFS), and overall survival (OS). RESULTS: Between July 2016 and November 2017, 12 and 10 patients with pancreatic and biliary cancer, respectively, with CDKN2A loss or mutation were treated with palbociclib. Twenty evaluable patients (10 per cohort) were included in the analysis. No patients had objective response or stable disease at 16 weeks, and both cohorts were closed. Two patients, neither with response, were determined to be ineligible. All patients were evaluated for safety, PFS, and OS. A median PFS of 7.2 weeks (90% CI, 4.0 to 8.0 weeks) and median OS of 12.4 weeks (90% CI, 4.7 to 23.1 weeks) were observed in the pancreatic cohort. A median PFS of 7.3 weeks (90% CI, 3.9 to 7.9 weeks) and median OS of 11.1 weeks (90% CI, 5.1 to 14.0 weeks) were observed in the biliary cohort. No unexpected toxicities were observed. CONCLUSION: Palbociclib monotherapy does not have clinical activity in patients with advanced pancreatic or biliary cancers with CDKN2A loss or mutation. Toxicity is similar to reported experience with palbociclib in other tumor types. [ABSTRACT FROM AUTHOR]

The current study has evaluated Shatt Al-Arab water using organic pollution index. The study included three stations, the first Al-Sharash, the second Al- Salhiya and the third area Al-Dweab. Water samples were monthly collected from December 2017 to November 2018. Five environmental parameters were used to calculate the organic pollution index (OPI) including Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Active nitrate (NO3), Ammonium ion (NH4) and Total Phosphate (TP). The highest biological oxygen demand was 9 mg.l-1 at Al- Sharash station in July and the lowest values 1mg.l-1 in the Al- Dweab station during December, January, February and April. The highest chemical oxygen demand (250 mg.l-1 was recorded at Al-Sharash station in September and the lowest value was 6.2 mg.l-1 in Al-Dweab station during December. Nitrates was recorded the highest value 41.51 mg nitrogen-nitrate.l-1 at Al-Salhiya station in May and lowest value 1.49 mg nitrogen- nitrate.l-1 at Al-Sharash station during December. The ammonium ion was recorded in highest value 7.7 mg.l-1 at Al- Salhiya station in December and the lowest value 0.5 mg. l-1 at Al-Sharash station during June, while phosphate value was 0.23 and 1.99 mg.l-1 were recorded at Al-Sharash station in August and July respectively. The highest value of organic pollution index was 2.56 at Al-Salihiya station in August and lowest value 0.69 in the Al-Dweab station in April, while the annual rate of organic pollution index for the first, second and third stations were 1.55, 1.81 and 1.47 respectively, and 1.61 for Shatt Al-Arab water. [ABSTRACT FROM AUTHOR]

Inlet and outlet keys are the main two components of piano key weir. Understanding the phenomena of flow over these two components is an important factor in the design of this structure. In this article, 2D investigation into the velocity and pressure distributions of the flow over individual inlet and outlet keys under different discharges has been performed using CFD technique. Analysis of the results provided information about the critical areas that should be taken into account when designing the PKW structure. [ABSTRACT FROM AUTHOR]

Recently, great development in 3D technologies facilitates digital preservation of cultural heritage. Najaf holy city in Iraq has a rich ancient cultural history, which includes historic groups of buildings, monuments, sites, natural heritage, and energy and sustainability systems in the heritage's buildings. The Center of Preserving of the Cities Heritage and Identity (CPCHI) at International Energy and Environment Foundation (IEEF) founded a first roadmap in preserving Iraqi cultural heritage and identity with 3D scanning, 3D virtual reality, and 3D printing technologies. Part of this project was dedicated to the holy city of Najaf because of its rich cultural heritage. In this part, we intend to share how these three dimensional technologies can be the first step of intervention to save Najaf history. Furthermore, this work highlights the accelerating risks threatening Najaf cultural treasures. We also aim to get our local peoples to think about what we as a community can do to save heritage within our reach, before it is lost to us forever. Not knowing about Najaf heritage is of course a key risk. Moreover, this work is intended to raise awareness of heritage issues in Najaf city by identifying those heritage places, monuments, sites, and the important objects. [ABSTRACT FROM AUTHOR]

This paper aims to investigate and quantify the effect of changing the crest length of a piano key weir on its discharge coefficient. Empirical equation relating the discharge coefficient with the crest length has been developed based on dimensional analysis by means of statistical computer software. Data were gathered by physical modeling of five 2-unit piano key weir models in an experimental flume 15 m long, 0.3 m wide and 0.45 m deep. Results showed that increasing the crest length has a major influence on the discharge capacity that may reach as much as 100%. The empirical equation estimates the value of discharge coefficient in terms of the dimensionless ratio of (crest length to the weir width), as well as the ratio of (total head to the weir height). It has showed good agreement with experimental results. [ABSTRACT FROM AUTHOR]

In this paper we apply methods of prediction with expert advice to real-world foreign exchange trading data with the aim of finding effective investment strategies. We start with the framework of the long-short game, introduced by Vovk and Watkins (1998), and then propose modifications aimed at improving the performance with respect to standard portfolio performance indicators. [ABSTRACT FROM AUTHOR]

Extensive experimental investigation has been performed to analyse the behaviour of piano key weir under submerged flow conditions. More than 2500 runs were performed on 14 physical models in an experimental rectangular flume, 15 m long and 0.3 m by 0.45 m cross-section. Effect of submergence phenomenon on the discharge capacity was studied for different discharge values. It was found that the discharge reduction factor Cs is mainly influenced by the submergence factor S. This effect starts when S is greater than the modular submergence limit which proved to be around 0.4 to 0.6. Models with different geometrical parameters were compared to each other and final conclusions about their effect on discharge capacity were achieved. However, the influence of all the geometrical parameters was small (less than 12%). [ABSTRACT FROM AUTHOR]

Mechanical degradation is often studied in single-cell proton exchange membrane (PEM) fuel cell stack models in assembly process. This however, can increase substantially when moving from assembly process to operation conditions; and also from single-cell to multiple cells. In this study, PEM fuel cell stacks consisting of 1, 3, and 5 cells with an active area of 25 cm² per cell have been simulated in operation mode. Three dimensional non-isothermal solid mechanics-CFD model of a PEM fuel cell stack, integrating the real full scale geometry of all components have been used to study the influence of the number of cells on the stress distribution in a running PEM fuel cell stack. Simulation of a running multi cells stack was successful and has not been previously seen in literatures work. The results showed that the center of the electrode tends to un-displacement. This un-displacement area increases by increasing the clamping torque. The deformations in the stack components during operation were about ten times higher than during assembly process. During assembly process, the increasing in the number of cells increases the total displacement distribution. These status were different during operation, the increasing in the number of cells enhances the uniformity of the total displacement. Increasing the number of cells enhances the uniformity of the mechanical state. The better contact pressure homogeneity was obtained with the greater number of cells and leads to the lower contact resistance. In general, the results showed lower stresses values with lower distributions and more homogeneous and uniformity in the stack that consisting of multi cells. [ABSTRACT FROM AUTHOR]

PEM fuel cell stack assembly process, including clamping pressure, material properties of each component, design (component thickness and cell active area), and number of cells in the stack are important factors influencing the performance and durability of the PEM fuel cell stack. Furthermore, when temperature and relative humidity increase during operation, the membrane absorbs water and swells. Since the relative position between the top and bottom end plates is fixed, the polymer membrane is spatially confined. Thus the GDL will be further compressed under the land and the intrusion into channel becomes more significant. Assembly pressure, contact resistance, membrane swelling and operating conditions, etc., combine to yield an optimum assembly pressure. The clamping pressure is therefore a critical parameter for optimal fuel cell performance and durability. Too high, too low, or inhomogeneous compressions have negative effects on the performance and durability of the stack. In this study, full three-dimensional, non-isothermal computational fluid dynamics (CFD) detailed model of a PEM fuel cell stack has been developed and coupled with a solid mechanics model to simulate the stress distribution inside the stack, which are occurring during fuel cell assembly (bolt assembling), and membrane swelling and cell materials expansion during fuel cell running due to the changes of temperature and relative humidity. The PEM fuel cell stack model simulated includes the following all components in full details; two end-plates, two current plates, two bi-polar plates with straight flow channels for reactants and cooling serpentine water flow channel on the upper face of cathode bi-polar plate, two GDLs, two gaskets, and, an MEA (membrane plus two CLs). The model is shown to be able to understand the many interacting, complex electrochemical, transport phenomena, with stress distribution inside the stack during operation on the performance and durability of the stack that have limited experimental data. Furthermore, the model is shown to be able to provide a computer-aided tool for design and optimize future fuel cell stack with much higher power density, long stack life, and lower cost. [ABSTRACT FROM AUTHOR]

3D printing and 3D scanning are increasingly used in archeology and in cultural heritage preservation. These 3D technologies provide museum curators, researchers and archeologists with new tools to capture in 3D ancient objects, artifacts or art pieces. They can then study, replicate, restore or simply archive them with much more details than traditional 2D pictures. It is even possible to 3D scan entire archeological sites to get a full 3D mapping. Iraq is too rich in ancient cultural heritage but unfortunately much of the hundreds of thousands of artifacts remain in archives of the museums worldwide. Having the exact copies of these ancient artifacts will allow the audience here to learn more about our heritage. The Center of Preserving of the Cities Heritage and Identity (CPCHI) at International Energy and Environment Foundation (IEEF) started a roadmap in preserving our ancient history with 3D scanning, 3D virtual reality and 3D printing technologies. As part of the project create high-quality 3D replicas of our cultural heritage, which are located in our museums and sites and most of them are spread around the world and then exhibit it in several venues throughout our country Iraq. Promising results were obtained in this project through printing of 3D models and generating 3D virtual reality models for our cultural heritage, based on the 3D scan of the original objects that submitted by some international museums and heritage institutes. We expect that this project will not only become vital in the field of replicate or reconstruction of ancient objects, but also for research, documentation, preservation and educational purposes, and it has the potential to serve these purposes in an accessible and all-inclusive way. [ABSTRACT FROM AUTHOR]

G. Kingsley Noble reported the possibility of orbital gland involvement in reproduction of spelerpine salamanders, particularly Eurycea, through rudimentary gross examination of the heads of male and female salamanders. In his report, Noble provided details from only one taxon of salamander, E. bislineata. To examine the variability of orbital glands with secondary sexual function in Eurycea, orbital glands of E. longicauda were assessed for sexual dimorphism and a distinct seasonal secretory cycle that mirrored the reproductive cycle. Orbital glands were found not to be sexually dimorphic in E. longicauda and possessed constant secretory activity in males and females throughout the year. Known secondary sexual glands (mental glands, caudal courtship glands, and cloacal glands) were sexually dimorphic between males and females and possessed a secretory cycle that could be correlated with events of the reproductive cycle, particularly mating activity. Thus, no evidence was found for orbital gland involvement in reproduction in E. longicauda. Orbital glands of both male and female E. longicauda are morphologically identical and produce copious lipoproteins throughout the year. Orbital gland secretions are potentially involved in lubrication of the eye and the prevention of fluid evaporation from the eye as described for lipoprotein secretions in other vertebrate lineages. [ABSTRACT FROM AUTHOR]

The offshore wind energy sector faces new challenges as it moves into deeper water deployment. To meet these challenges, new and efficient foundation solutions are required. One potential solution is to upscale onshore screw piles but they require verification of performance for new geometries and demanding loading regimes. This paper presents a three-dimensional finite-element analysis investigation of screw pile behaviour when subjected to combined vertical and lateral loading in sand. In the investigation, the screw pile length and helical plate diameter were varied on piles with a fixed core diameter while subjecting the piles to combined axial and lateral loading. The results were compared with results from straight shafted piles with the same core diameter. The results of the analysis revealed that vertical compression loads increased the lateral capacity of the screw piles whereas vertical uplift loads marginally reduced the lateral capacity. The downside of this enhanced lateral capacity is that the screw piles experience higher bending moments. This suggests that, when using screw piles for offshore foundation applications, structures should be designed to maintain axial compressive loads on the piles and induced bending moments need to be adequately assessed when deciding on appropriate structural sections. [ABSTRACT FROM AUTHOR]

Obesity increases risk for liver toxicity by the anti-leukemic agent asparaginase, but the mechanism is unknown. Asparaginase activates the integrated stress response (ISR) via sensing amino acid depletion by the eukaryotic initiation factor 2 (eIF2) kinase GCN2. The goal of this work was to discern the impact of obesity, alone versus alongside genetic disruption of the ISR, on mechanisms of liver protection during chronic asparaginase exposure in mice. Following diet-induced obesity, biochemical analysis of livers revealed that asparaginase provoked hepatic steatosis that coincided with activation of another eIF2 kinase PKR-like endoplasmic reticulum kinase (PERK), a major ISR transducer to ER stress. Genetic loss of Gcn2 intensified hepatic PERK activation to asparaginase, yet surprisingly, mRNA levels of key ISR gene targets such as Atf5 and Trib3 failed to increase. Instead, mechanistic target of rapamycin complex 1 (mTORC1) signal transduction was unleashed, and this coincided with liver dysfunction reflected by a failure to maintain hydrogen sulfide production or apolipoprotein B100 (ApoB100) expression. In contrast, obese mice lacking hepatic activating transcription factor 4 (Atf4) showed an exaggerated ISR and greater loss of endogenous hydrogen sulfide but normal inhibition of mTORC1 and maintenance of ApoB100 during asparaginase exposure. In both genetic mouse models, expression and phosphorylation of Sestrin2, an ATF4 gene target, was increased by asparaginase, suggesting mTORC1 inhibition during asparaginase exposure is not driven via eIF2-ATF4-Sestrin2. In conclusion, obesity promotes a maladaptive ISR during asparaginase exposure. GCN2 functions to repress mTORC1 activity and maintain ApoB100 protein levels independently of Atf4 expression, whereas hydrogen sulfide production is promoted via GCN2-ATF4 pathway. [ABSTRACT FROM AUTHOR]

Proton Exchange membrane (PEM) fuel cells are still undergoing intense development, and the combination of new and optimized materials, improved product development, novel architectures, more efficient transport processes, and design optimization and integration are expected to lead to major gains in performance, efficiency, durability, reliability, manufacturability and cost-effectiveness. PEM fuel cell assembly pressure is known to cause large strains in the cell components. All components compression occurs during the assembly process of the cell, but also during fuel cell operation due to membrane swelling when absorbs water and cell materials expansion due to heat generating in catalyst layers. Additionally, the repetitive channel-rib pattern of the bipolar plates results in a highly inhomogeneous compressive load, so that while large strains are produced under the rib, the region under the channels remains approximately at its initial uncompressed state. This leads to significant spatial variations in GDL thickness and porosity distributions, as well as in electrical and thermal bulk conductivities and contact resistances (both at the ribe-GDL and membrane-GDL interfaces). These changes affect the rates of mass, charge, and heat transport through the GDL, thus impacting fuel cell performance and lifetime. In this study, computational fluid dynamics (CFD) model of a PEM fuel cell has been developed to simulate the pressure distribution inside the cell, which are occurring during fuel cell assembly (bolt assembling), and membrane swelling and cell materials expansion during fuel cell running due to the changes of temperature and relative humidity. The PEM fuel cell model simulated includes the following components; two bi-polar plates, two GDLs, and, an MEA (membrane plus two CLs). This model is used to study and analyse the effect of channel geometrical configuration on the mechanical behaviour of the PEM fuel cell components. The analysis helped identifying critical parameters and shed insight into the physical mechanisms leading to a fuel cell durability under various conditions. The model is shown to be able to understand the effect of pressure distribution inside the cell on the performance and durability that have limited experimental data. [ABSTRACT FROM AUTHOR]

Fuel cell technology is expected to play an important role in meeting the growing demand for distributed power generation. In an ongoing effort to meet increasing energy demand and to preserve the global environment, the development of energy systems with readily available fuels, high efficiency and minimal environmental impact is urgently required. A fuel cell system is expected to meet such demands because it is a chemical power generation device, which converts the chemical energy of a renewable clean fuel (e.g. Hydrogen) directly into electrical energy. Still a maturing technology, fuel cell technology has already indicated its advantages, such as its high-energy conversion efficiency, modular design and very low environmental intrusion, over conventional power generation equipment. Among all kinds of fuel cells, proton exchange membrane (PEM) fuel cells have many superior advantages. These advantages have sparked development efforts in various quarters of industry to open up new field of applications for PEM fuel cells. Three key issues limiting the widespread commercialization of the PEM fuel cells technology which are better performance, lower cost, and long cell life. The strategy of the Fuel Cell Research Center at the International Energy and Environment Foundation (IEEF) is to develop the PEM fuel cells to improve their lifetime with a much higher power density and lower cost. An overview of innovations in this field is presented using the published results of the center over the last decade. These innovative improvements will show a new scenario for the future fuel cell market of the next years. [ABSTRACT FROM AUTHOR]

Self-management ( SM) programmes are commonly used for initial treatment of patients with temporomandibular disorders ( TMD). The programmes described in the literature, however, vary widely with no consistency in terminology used, components of care or their definitions. The aims of this study were therefore to construct an operationalised definition of self-management appropriate for the treatment of patients with TMD, identify the components of that self-management currently being used and create sufficiently clear and non-overlapping standardised definitions for each of those components. A four-round Delphi process with eleven international experts in the field of TMD was conducted to achieve these aims. In the first round, the participants agreed upon six principal concepts of self-management. In the remaining three rounds, consensus was achieved upon the definition and the six components of self-management. The main components identified and agreed upon by the participants to constitute the core of a SM programme for TMD were as follows: education; jaw exercises; massage; thermal therapy; dietary advice and nutrition; and parafunctional behaviour identification, monitoring and avoidance. This Delphi process has established the principal concepts of self-management, and a standardised definition has been agreed with the following components for use in clinical practice: education; self-exercise; self-massage; thermal therapy; dietary advice and nutrition; and parafunctional behaviour identification, monitoring and avoidance. The consensus-derived concepts, definitions and components of SM offer a starting point for further research to advance the evidence base for, and clinical utility of, TMD SM. [ABSTRACT FROM AUTHOR]

A three-dimensional, multi-phase, non-isothermal computational fluid dynamics model of a proton exchange membrane fuel cell has been used and developed to investigate the hygro and thermal stresses in polymer membrane, which developed during the cell operation due to the changes of temperature and relative humidity. The behaviour of the membrane during operation of a unit cell has been studied and investigated under real cell operating conditions. The results show that the non-uniform distribution of stresses, caused by the temperature gradient in the cell, induces localized bending stresses, which can contribute to delaminating between the membrane and the gas diffusion layers. These stresses in the membrane may explain the occurrence of cracks and pinholes in the membrane under steady-state loading during regular cell operation. The results show that the maximum displacements in membrane for the low, intermediate and high load conditions were 2.58, 2.66, and 2.78 µ m respectively. [ABSTRACT FROM AUTHOR]

This paper investigates mechanical and thermal stresses that arise in the exhaust valve due to its operating with and without thermal coating layer (ceramic) on face exhaust valve. Three dimensional models of an exhaust valve four cylinders, four stroke, and direct injection diesel engine have been presented. The governing equations were discretized using a finite-volume method (FVM) and solved using multi-physics COMSOL® package Version 5. The engine's exhaust valve crown is coated with various materials in different thermal conductivity such as (Gd2Zr2O7), over a 150µm thickness of bond coat. The maximum thickness of coating is about 300 µm. Results indicate that after creating a coating layer exhaust valve the temperature distribution, temperature gradients distribution, von-Mises stress distribution and displacement distribution are decreased. [ABSTRACT FROM AUTHOR]

A PEM fuel cell stack is laminated with a number of plate-type cells, and the latest model is assembled by compression from both ends of plates.PEM fuel cells are exposed to high magnitude vibrations, shocks, and cyclic loads in many applications. Vibrations during operation show significant impact in the longer run of the fuel cells. Frequencies which are not close to the resonant frequencies or natural frequencies show very little effect on the overall performance. However, if the frequency ranges of operation approaches the resonant frequency range, the probability of component failure increases. It is possible that there will be lateral transition of cells or leakage of fuel gas and coolant water. Therefore, it is necessary to evaluate the effects vibration has on the fuel cell. This work aims to understand the vibration characteristics of a PEM fuel cell stack and to evaluate their seismic resistance under a vibration environment. Natural frequencies and mode shapes of the PEM fuel cell stack are modelling using finite element methods (FEM).A parametric study is conducted to investigate how the natural frequency varies as a function of thickness, Young's modulus, and density for each component layer. In addition, this work provides insight into how the natural frequencies of the PEM fuel cell stack should be tuned to avoid high amplitude vibrations by modifying the material and geometric properties of individual components. The mode shapes of the PEM fuel cell stack provide insight into the maximum displacement exhibited under vibration conditions that should be considered for transportation and stationary applications. [ABSTRACT FROM AUTHOR]

Experimental investigation has been performed to understand the hydraulic behaviour of non-rectangular piano key weir where either the side wall angle or the side wall inclination angle is greater than zero. Five physical models were prepared: one standard type-A rectangular model, and four non-rectangular models designed in similar dimensions to the rectangular one. Tests were conducted in a 15m long, 0.3m wide and 0.45 m deep rectangular glass-walled experimental flume. Effects of side wall angle and side wall inclination angle on discharge coefficient were investigated, so that the head-discharge relationship for each model is achieved. It was concluded that changing those angle to about 10° has negative effect on discharge capacity, while changing them around 5° can increase the capacity when appropriate change in the inlet and outlet keys widths ratio. [ABSTRACT FROM AUTHOR]