This study aimed to investigate the effects of stiffeners on buckling of thin cylindrical shells under uniform axial compression. To this end, more than 300 finite element models of stiffened cylindrical shells were prepared. The variables considered are shell thickness, number, dimension and the location of the vertical and horizontal stiffeners as well as circular symmetrical imperfections. R...

http://dx.doi.org/10.1016/j.anbehav.2014.10.004 0003-3472/© 2014 The Association for the Study of A In resource defence polygyny, where males defend resources that females use for reproduction, the resource characteristics preferred by the two sexes are expected to match. We tested this expectation by comparing the shell characteristics preferred by males and females in the shell-brooding cichl...

Phosphorus is an essential nutrient for aquatic plants and animals. The acceptable range phosphorus in water from 0.01 to 0.03 mg/L. However, excessive use can result biodiversity loss pollution endanger creatures human health because the pollutants are non-biodegradable thus accumulate over time. This work investigated removal of synthetic wastewater containing KH2PO4 via adsorption using calc...

in this work, efficiency and performance of hazelnut shells (hs) adsorbent was examined for the removal and recovery of direct red 12b (dr12b) from wastewater. the absorbance of dr12b was measured spectrophotometrically at λmax=523 nm before and after adsorption of dr12b. the maximum removal was 99.8% for 30 mg l –1 ofdr12b concentration on 0.3 gr hs adsorbent. acidic ph was favourable for the ...

kopet-dagh basin is located in north and northeast of iran. khangiran formation is one of the most important formations of paleogene deposits. for study of khangiran formation bivalves, chehelkaman syncline section has been selected. this section located in west of sarakhs city, east of kopet-dagh basin. lithology of this formation in the sarakhs region composed of marl, marly limestone and sil...

In the Bay of Saint-Brieuc, a 3110 ha tidal bay in NW France, English channel, the cockle (Cerastoderma edule) has been collected by traditional fishing methods for many decades without any evaluation or management of this resource taking place. Since 2001, the national Natural Reserve of the bay of Saint-Brieuc has carried out an evaluation of the stock and a mapping of the cockle fishing grou...

Ecosystem engineering research has recently demonstrated the fundamental importance of non-trophic interactions for food-web structure. Particularly, by creating benign conditions in stressful environments, ecosystem engineers create hot beds of elevated levels of recruitment, growth, and survival of associated organisms; this should fuel food webs and promote production on the ecosystem scale....

The present study aims to describe the population dynamics and state of the fishery of the mud cockle Anadara tuberculosa (locally know as piangua) in three harvesting areas along the Pacific coast of Costa Rica (Chomes, Purruja and Rincón) and to put the results in context with this species in other Costa Rican areas as well as with other Anadara spp. around the globe. The study is based on a ...