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For a long time, electricity is supplied by means of firing the fossil fuels in thermal power plants. Now, it is well-known that the activity has many environmental and health issues, which are sharply menace the future of earth and humanity. Photovoltaic (PV) system is one of the popular renewable types of energy generation, which is available in most parts of the earth. Unfortunately, temperature rise in a PV module, leads to a significant reduction in its electrical efficiency. In this paper, two methods of wind blowing and mounting fins are considered separately and simultaneously, to overcome the mentioned weak-point. The wind velocity is set to 2 km/h. So, four cases are assessed, experimentally. As results, it was revealed that wind blowing of 2 km/h is more effective than fins in cooling PV module, so that, it can create more than 15 °C lower temperature than mounting fins. The mentioned temperature reduction leads to enhance the electrical efficiency and output power by 2.4% and 21.7%, respectively. In order to show the accuracy of results, all experimental outcomes in electrical efficiency were compared with the analytical formula. Moreover, the environmental evaluation of commissioning a 10 kW PV power plant with the proposed cases are reported, too. [ABSTRACT FROM AUTHOR]

Zircon U-Pb-Hf isotopes, integrated with bulk-rock major, trace element, and isotopic compositions of amphibolites from the Makran ophiolitic mélange complex (OMC), carry implications on the evolution of the Neo-Tethys Ocean. Field and petrographical-geochemical data confirm these amphibolites as products of the metamorphism of a mafic protolith. Zircons from the amphibolites have U-Pb ages of Late Early Permian (273 Ma) to Late Triassic (210 Ma), and their εHf(t) values vary from +6.32 to +15.4. The Makran amphibolites are geochemically similar to transitional- or enriched-MORBs. The 143Nd/144Nd(t) ratios for amphibolites range from 0.51260 to 0.512551, and 87Sr/86Sr(t) from 0.704433 to 0.706244. The Pb-isotope composition of these rocks is radiogenic, ranging from 15.61-15.64 for 207Pb/204Pb(t), 18.98-19.21 for 206Pb/204Pb(t) and 38.88-39.36 for 208Pb/204Pb(t). The isotopic and geochemical signatures of these rocks suggest that they were most likely formed during continental rifting and originated from a relatively enriched mantle source. This is also attested by their high zircon Ce/Ce* ratios. We interpret these amphibolites related to the Permian-Triassic plumes that triggered Gondwana rifting to open the Neo-Tethyan Ocean before metamorphosed, fragmented, and accreted into the Makran accretionary complex probably during Early to Late Cretaceous time. [ABSTRACT FROM AUTHOR]

The Makran complex in southeast Iran provides a spectacular subduction-related accretionary complex to understand the mechanism of oceanic accretion and the evolution of subduction zones. In this paper, we present new major and trace element data as well as isotopic compositions of mafic volcanic blocks from the Makran ophiolitic mélange complex (OMC). Our aim is to assess the genesis of these rocks and discuss their implications on the evolution of Neotethys Ocean. These volcanic blocks are composed mainly of basalts with minor trachytes. The Makran lavas are occasionally interlayered with tuff layers. Zircons from these tuffs give U-Pb ages of 95 Ma, which is well in accordance with the reposted microfossil data for the interlayered pelagic limestones with pillow lavas. Makran basalts can be geochemically subdivided into four groups; normal to transitional MORB, enriched-MORB, Plume-type MORB and alkaline (-OIB-like) basalts. The OIB-like pillow lavas are represented by high values of Th/Tb (6.3–7.4) which are higher than other basalts (group 1 = 0.3–0.8; groups 2 = 0.7–1.6; group 3 = 1.58–1.36).143Nd/144Nd(t) ratios for basalts ranges from 0.51247 to 0.51292, whereas 87Sr/86Sr(t) isotopic composition of the OMC lavas varies from 0.704433 to 0.709466. The Pb isotopic composition of the lavas are quite high, ranging from 15.49–15.66 for 207Pb/204Pb(t), 18.09–19.12 for 206Pb/204Pb(t) and 37.80–39.23 for 208Pb/204Pb(t). The chemistry of these rocks suggests that they were formed most likely in an oceanic setting with clear plume-ridge interaction. These rocks can form from partial melting of a highly heterogeneous mantle source, which is extensively metasomatized with deep mantle OIB-type components. We suggest these rocks have been generated in an oceanic ridge with plume-ridge interaction, similar to the Iceland-Reykjanes Ridge, before being fragmented and accreted into the Makran accretionary complex. [ABSTRACT FROM AUTHOR]

There has been a growing interest in assessing the condition and quality of life in older adult population, and factors contributing to it. In this context, fear of falling syndrome is introduced as one of the main factors that can affect the quality of life in the general adult population. However, little is known about the relationship between fear of falling and other disorders in older adults, particularly among the Middle East population. Here we investigated the associations between fear of falling and anxiety and depression disorders. A standardized questionnaire was used to assess sociodemographic variables and physical health condition. Subsequently, fear of falling and anxiety and depression scales were assessed using the Falls Efficacy Scale International and the Hospital Anxiety Depression Scale, respectively. Our results highlighted the high risk of having anxiety and depression disorders among older adults. The findings also indicate that physical and mental health disorders play a significant role in incident fear of falling. Therefore, improving mental health might lend controlling fear of falling syndrome, which then preventing falls incident and subsequent injury in older adult population. [ABSTRACT FROM AUTHOR]

Exposure to extremely low-frequency electromagnetic fields (ELF-EMF) is inevitable in some industries. There are concerns about the possible effects of this exposure. The present study aimed to investigate the effect of chronic exposure to extremely low-frequency electromagnetic fields on sleep quality, stress, depression and anxiety among power plant workers. In this cross-sectional study, 132 power plant workers were included as the exposed group and 143 other workers were included as the unexposed group. The intensity of ELF-EMF at work stations was measured by using the IEEE Std C95.3.1 standard and then the time weighted average was calculated. Sleep quality, stress, depression and anxiety were measured by using the Pittsburgh Sleep Quality Index Questionnaire; and the Depression, Anxiety and Stress Scale. The workers in the exposed group experienced significantly poorer sleep quality than the unexposed group. Depression was also more severe in the exposed group than the unexposed group (P = 0.039). Increased exposure to ELF-EMF had a direct and significant relation with increased stress, depression, and anxiety. Sleep quality in technicians with the highest exposure was significantly lower than the other groups. This study suggests that long-term occupational exposure to ELF-EMF may lead to depression, stress, anxiety and poor sleep quality. [ABSTRACT FROM AUTHOR]

Essential oils from three species of plants comprising three plant families were obtained by Clevenger-type water distillation. The major compounds in these essential oils were identified with GC-MS and their insecticidal activity against adult cotton aphid,Aphis gossypiiGlover tested with dosage-mortality bioassays. We examined mortality only for viviparous adults because sizeable aphid populations on cucumber (Cucurbitaceae) hosts are largely produced by these wingless, parthenogenic females. Three of the oils were directly applied to aphid females in randomised blocks at 25 ± 2 °C and 60 ± 5% R.H. and under a L16:D8 photoperiod. Essential oils were mixed with a non-toxic emulsifying agent, Tween 80. Results show adverse contact effects of essential oils studied in the control of cotton aphid. Probit analysis and LC50at concentrations at different exposures showed aphids were incapacitated and killed by aliphatic aldehydes, phenols and monocyclic terpenes contained inAzadirachta indica, Eucalyptus camaldulensisandLaurus nobilis. LC50on cotton aphid, for azadirachtin eucalyptus and laurel essential oils were respectively 5389, 9515 and 13730 ppm. In the current study, efficacy in respect to the contact toxicity (LC50) followed the order:A. indica > E. camaldulensis > L. nobilisafter 24 h treatment. Our results show quantitative and qualitative differences in the chemical composition and insecticidal activities of our essential oils. All oils became insect toxic as concentration increased. According to the results, essential oils of all the three plants have the potential to be employed in the pest management programmes that can be used in protection of greenhouse conditions against cotton aphid. [ABSTRACT FROM PUBLISHER]

The cotton aphid,Aphis gossypiiGlover (Hem: Aphididae), is one of the most injurious pests of fruits, vegetables and ornamental plants worldwide, both outdoor and indoor. Currently, the main method of control of this pest is through application of pesticides which is mostly accompanied by the resistance of the pest against pesticide(s). The resurgence of resistant aphid populations brings about further contamination of foodstuff and environment. Essential oils obtained from the aerial parts of plants may have the potential to be an alternative to synthetic pesticides, since they have been demonstrated to possess a wide range of bioactivities against insects and mites. So, the aim of the current study was to investigate the effect of essential oils extracted from three different plants namely:Azadirachta indicaAdr. Juss. (Meliaceae),Eucalyptus camaldulensisDehn. (Myrtaceae) andLaurus nobilisL. (Lauraceae) againstA. gossypii. The LC50values of essential oils ofA. indica,E. camaldulensisandL. nobilisagainstA. gossypiiwere 1.96, 2.28 and 3.16 μl L−1air, respectively. This shows thatA. indicapossesses the highest lethal activity whereasL. nobilisthe lowest. These data suggest that essential oils of all the three plants have the potential to be employed in the pest management programmes designed for a control ofA. gossypiiunder greenhouse conditions. [ABSTRACT FROM PUBLISHER]