291 research outputs found
June 20, 1990 Earthquake of Northern Iran: An Overview
On the day of June 20, 1990 at 21:00 GMT (June 21, 1990, at 00:30 local time) a destructive earthquake of magnitude 7.6 shook Northern provinces of Iran. It caused widespread geotechnical and structural damages covering an approximate area of 10,000 sq. km resulting in 37,000 life losses, 100,000 injuries, and 100,000 building failures leaving more than 400,000 people homeless. This paper summarizes the post-earthquake investigations and discusses the general engineering aspects of the June 20, 1990 seismological, geotechnical, and structural aspects of the event. Lessons learned are also discussed
Establishment of a New Urban Solid Waste Management Programs in Mazandaran Province, North of Iran
This study reports residentsā preferences to establish a new urban solid waste management programs results from a double-bounded dichotomous choice contingent valuation method and choice experiment in Mazandaran province, north of Iran. In order to analysis the residentsā preferences, a dichotomous hypothetical market and a choice sets with different attributes and options were used For estimation of two mentioned methods, the normal logit and conditional logit were applied. In addition, an empirical comparison of the welfare measures derived from the doublebounded DC-CVM and CE is conducted. The main results show that there is no significant difference between the values derived from the two methods. The mean of WTP to establish a new solid waste management programs in CV and CE were estimated 2.45 and 2.61 US per a month. The results suggest that both double-bounded DC-CVM and CE can be successfully stablished for improvement environmental level quality in Mazandaran province. This paper could provide the basis for further development of other new programs on sustainable urban management of solid waste in Mazandaran province.Keywords: Dichotomous choice, Willingness to pay, Solid waste management, Mazandaran province, Ira
Essential Oil Variability of Superior Myrtle (Myrtus communis L.) Accessions Grown under Same Conditions
Myrtle (Myrtus communis L., Myrtaceae) has numerous applications in pharmacology, food technology, and cosmetic industry. The current research aimed at measuring variations in the leaf essential oil (EO) compositions of 14 superior myrtle accessions originating in natural habitats of south Iran. The plants were grown under greenhouse conditions. Fresh leaf samples were harvested in June 2021. Based on dry matter, the extractable amount of EO in the accessions ranged from 0.42% (BN2) to 2.6% (BN5). According to GC/MS analysis, the major compounds in the EO were Ī±-pinene (2.35ā53.09%), linalyl acetate (0ā45.3%), caryophyllene oxide (0.97ā21.8%), germacrene D (0ā19.19%), Ī±-humulene (0ā18.97%), 1,8-cineole (0ā18.0%), limonene (0ā17.4%), and p-cymene (0ā13.2%). These myrtle accessions were classified into four groups, including I: caryophyllene oxide/germacrene D/Ī±-humulene/methyl eugenol chemotype; II: Ī±-pinene/p-cymene/Ī±-humulene and (E)-Ī²-caryophyllene; III: Ī±-pinene/1,8-cineole, and linalool; IV: linalyl acetate/Ī³-terpinene/1,8, cineole/limonene. These classifications were established by considering the main EO components using hierarchical cluster analysis (HCA) and principal component analysis (PCA). In summary, this study provided new insights into available opportunities of selecting suitable genotypes for commercial cultivation purposes and planning breeding programs in the future
Allometric Scaling Reveals Evolutionary Constraint on Odonata Wing Cellularity via Critical Crack Length
Scaling in insect wings is a complex phenomenon that seems pivotal in maintaining wing functionality. In this study, the relationship between wing size and the size, location, and shape of wing cells in dragonflies and damselflies (Odonata) is investigated, aiming to address the question of how these factors are interconnected. To this end, WingGram, the recently developed computerāvisionābased software, is used to extract the geometric features of wing cells of 389 dragonflies and damselfly wings from 197 species and 16 families. It has been found that the cell length of the wings does not depend on the wing size. Despite the wide variation in wing length (8.42 to 56.5 mm) and cell length (0.1 to 8.5 mm), over 80% of the cells had a length ranging from 0.5 to 1.5 mm, which was previously identified as the critical crack length of the membrane of locust wings. An isometric scaling of cells is also observed with maximum size in each wing, which increased as the size increased. Smaller cells tended to be more circular than larger cells. The results have implications for bioāmimetics, inspiring new materials and designs for artificial wings with potential applications in aerospace engineering and robotics
A combination of GFRP sheets and steel cage for seismic strengthening of shear-deficient corner RC beam-column joints
International Institute of Earthquake Engineering and Seismology (IEES), project number 7342
Ī±4Ī²1 integrin and erythropoietin mediate temporally distinct steps in erythropoiesis: integrins in red cell development
Erythropoietin (Epo) is essential for the terminal proliferation and differentiation of erythroid progenitor cells. Fibronectin is an important part of the erythroid niche, but its precise role in erythropoiesis is unknown. By culturing fetal liver erythroid progenitors, we show that fibronectin and Epo regulate erythroid proliferation in temporally distinct steps: an early Epo-dependent phase is followed by a fibronectin-dependent phase. In each phase, Epo and fibronectin promote expansion by preventing apoptosis partly through bcl-xL. We show that Ī±4, Ī±5, and Ī²1 are the principal integrins expressed on erythroid progenitors; their down-regulation during erythropoiesis parallels the loss of cell adhesion to fibronectin. Culturing erythroid progenitors on recombinant fibronectin fragments revealed that only substrates that engage Ī±4Ī²1-integrin support normal proliferation. Collectively, these data suggest a two-phase model for growth factor and extracellular matrix regulation of erythropoiesis, with an early Epo-dependent, integrin-independent phase followed by an Epo-independent, Ī±4Ī²1-integrinādependent phase
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A combination of GFRP sheets and steel cage for seismic strengthening of shear-deficient corner RC beam-column joints
International Institute of Earthquake Engineering and Seismology (IEES), project number 7342
Interactive effect of replacing Dunaliella salina algae by agricultural by-products and probiotic Lactobacillus rhamnosus on digestive enzymes activity of Artemia franciscana
This study was carried out to evaluate the effect of replacing Dunaliella salina algae by agricultural by-products (wheat bran, rice bran and wheat/rice bran) and probiotic bacteria Lactobacillus rhamnosus on digestive enzymes activity of Artemia franciscana in a 17-day period post hatch. The study was a 4Ć2 factorial experiment carried out as a completely randomized design trial consisting of different dietary treatments (combinations of various substitution levels of Dunaliella salina by wheat bran, rice bran and wheat/rice bran along with probiotic Lactobacillus rhamnosus). All treatments were performed in triplicates. At the end of the trial, digestive enzymes activity was assayed. The results revealed that Artemia fed wheat bran without any dietary probiotic supplementation showed significantly higher amylase activity (2.06Ā±0.3Ī¼mol maltose mg protein-1 min-1) (p<0.05). Treatment fed Dunaliella salina algae and probiotic showed significantly higher alkaine protease activity (7.11Ā±0.87 U mg protein-1 min-1) and those fed wheat/rice bran with probiotic had significantly higher lipase activity (0.09Ā±0.005 mmol p-nitrophenol mg protein-1 min-1 ) (p<0.05). It was revealed that dietary probiotic inclusion resulted in decreased amylase activity whilst its effect on the alkaline protease and lipase activities were totally dependent upon the feed ingredients (e.g., simultaneous feeding of artemia by Dunaliella salina algae and probiotic led to higher alkaline protease activity, while receiving probiotic resulted in higher lipase activity in group fed wheat/rice bran). Our results also showed that digestive enzyme profile of Artemia franciscana was responsive to dietary treatment. Conclusively, using wheat/rice bran in artemia pond culture would result in inferior digestive enzymes activity especially alkaline protease and lipase with subsequent effects on nutrient digestion/absorption efficiency and undesirable effects on pond productivity and final product quality
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