Mutual interaction of salinity and dietary protein level on growth, survival and body composition of narrow clawed cray fish (Astacus leptodactylus)

In this study Astacus leptodactylus were tested for 8 week with three practical diets containing three crude protein (30, 35 and 40%) and isoenergetic level (370kcal/100 g) in fresh water and brackish water of Caspian Sea. In this test, 6 treatments were used with three replicates in 18 fiberglass tank (110 liter). Each tank had 5 narrow clawed Cray fish (mean (±SD) individual weight=17±2.3g) and totally 90 clawed Cray fish were stocking. Result indicates mean weight of Cray fish in fresh water and brackish water were 14.82 and 12.73, respectively, that were significantly different. The highest survival occurred in interaction between protein (30%) and salinity (0) (95.55%) and lowest survival occurred in protein 40 – salinity (12) that were significantly different. The highest specific growth rate (SGR), weight gain (WG), Protein Efficiency Ratio (PER), Net Protein Utilization (NPU) and lowest Feed Conversion Ratio (FCR), demonstrated that dietary (protein 30% and fresh water) which had no significantly differences. Result of this study showed that the highest protein of body composition were in practical diet containing 30% protein and 0 salinity (freshwater) that were significantly different with other treatment

Sustainable high strength steel flush end plate beam-tocolumn composite joints with deconstructable bolted shear connectors

The design of engineering structures for deconstructability can reduce the energy and cost required for their demolition and the disposal of their construction waste, and it also enhances the sustainability of a building by allowing for easy dismantling and the reuse or recycling of structural components and construction materials at the end of the service life of the building. In addition, using high performance materials such as High Strength Steel (HSS) can improve the sustainability of a structure by providing for higher design stresses and accordingly reducing the self-weight of the structure. This paper describes the results of four full-scale beam-to-column deconstructable composite joints with HSS S690 flush end plates. The structural behaviour of the new system in conjunction with application of post-installed friction-grip bolted shear connectors for developing deconstructable composite floors is investigated. The test results show that the proposed composite beam-tocolumn joints can provide the required strength and ductility according to EC3 and EC4 specifications, and that the system can be easily deconstructed at the end of the service life of the structure as a proof of concept

The performance of a cable-stayed bridge pylon under close-range blast loads

Recent bridge collapses have raised an awareness of, and a concern for, the safety and robustness of bridges subjected to blast loading scenarios. The incident pressure generated by the explosion can cause severe structural damage and a loss of critical structural members, resulting in partial collapse of the bridge. Previously, most relevant research effort has been devoted to understanding the response of buildings under blast loading and to develop guidelines to increase the resistance of such structures, while relatively little research attention has been focused on bridge structures. Recent advancements in numerical methods have enabled the viable and cost-effective simulation of complicated blast scenarios, and hence these methods provide a useful reference for safeguarding design and assessment of critical infrastructure. To reduce the computational costs, previous studies on long span bridges under blast loads typically take advantage of sub-structuring techniques, in which only part of the structure is modelled. However, such oversimplifications can lead to erroneous results. Accordingly, this study is an attempt to simulate the dynamic response of an entire cable-stayed bridge subjected to blast loading based on best practice techniques obtained from the literature. The response of a steel bridge, designed according to the minimum requirements of the Australian Standard AS5100, is investigated when subjected to blast loads ranging from small to large explosions at different positions above the deck using numerical simulations. In addition, the potential effects of blast loads on different structural components (i.e. the deck and pylons) are discussed and possible blast mitigation strategies such as the application of FRP and optimization of the geometry of the pylons are investigated

The predictive model for strength of inclined screws as shear connection in timber-concrete composite floor

Interest in timber-concrete composite (TCC) floors has increased over the last 30 years. TCC technology relies on timber and concrete members acting compositely together. Both timber and concrete exhibit a quite brittle behaviour in bending/tension and compression respectively whilst the shear connection is identified as the only contributor of ductile behaviour. Therefore, the strength, stiffness and arrangement of the shear connection play a crucial role in the structural design of TCC. There are only few investigations on analytical closed-form equation to predict the stiffness and strength of TCC joints as input values to design a partially composite floor. For example, Johansen's yield theory was adopted as European yield model in Eurocode 5. However, the equations are limited to vertically inserted dowels or screws and Eurocode 5 recommends that the strength and stiffness of unconventional joints should be determined by push-out tests. Previous investigations reported that the inclined shear connector significantly increase the initial stiffness and ultimate strength of the TCC joints and consequently composite floor. This paper presents a model for the strength ofTCC joint using crossed (±45°) proprietary screws (SFS Intec). The Johansen yield theory is extended to derive the strenght model of TCC joint with crossed (±45°) screws which are loaded in tension and compression. The model is an upper bound plastic collapse model that assumes the behaviour of timber and screw perfectly plastic with undamaged concrete. The failure modes considers of yield of screw, in tension or shear, and some combined modes assuming screw withdrawal, lateral crushing of the timber and the development of plastic hinges in the screw. The experimental aspect of the research consists of push-out tests and aims to verify the strength model of TCC joints with inclined screws. The failure modes are also investigated. The model seems to be reasonably accurate in predicting both the characteristic strength and failure mode. This research suggests the model to facilitate the design of inclined screw shear connections for TCC construction. © 2013 Taylor & Francis Group

Ultrasound - guided access during percutaneous nephrolithotomy: Entering desired calyx with appropriate entry site and angle

Objectives: To evaluate the success of ultrasonography directed renal access in entering the target calyx from proper entry site and in the direction of renal pelvis during percutaneous nephrolithotomy (PCNL). Materials and Methods: PCNL cases who were operated on by one fellow from May- June 2014 were included in this study. A vertically placed ultrasound probe on the patient flank in prone position was used to identify the preselected target calyx. Needle was advanced through needle holder and fluoroscopy was used to document the entered calyx, site and angle of entry. Results: Successful entering to the target calyx was achieved in 43 cases (91). Successful entry with appropriate entry site and angle was observed in 34 cases (72). Reasons for failure were minimal hydronephrosis, upper pole access and high lying kidneys. Conclusions: Although it is feasible to access a preselected calyx by ultrasonography guidance during PCNL, but entry to the calyx from the appropriate site and direction is another problem and needs more experience. In cases of minimal hydronephrosis, superior pole access or high lying kidneys, ultrasonography is less successful and should be used with care

Investigating the environmental impact of reinforced-concrete and structural-steel frames on sustainability criteria in green buildings

Reducing the detrimental impact of human activities on our environment is an essential need. Buildings have a significant role in accomplishing this need, which necessitates the conduction of comprehensive research that adequately identifies the underlying factors and then seeks sustainable solutions. Green buildings have been one of the critical initiatives to lessen the negative impact of human endeavors on the environment. The structural frame is one of the most critical elements of buildings, especially owing to their impact on the environment. This study investigates how structural building frames perform according to sustainability criteria. A questionnaire was used to identify the relevant sustainability criteria, and a hybrid Delphi-SWARA model was used to determine the relative importance of eight comprehensive prioritized criteria. A building was simulated with DesignBuilder software to quantify the environmental impact of two main types of structural frames, reinforced concrete (RC) and structural steel (SS) frames, on sustainability criteria. Results illustrated that RC-framed buildings have a less detrimental impact on the environment due to less energy consumption and carbon emissions. The energy consumption in RC-framed buildings was 2.3% less in electricity consumption and 2.7 less in natural gas consumption. In addition, 88 tonnes of CO2 emission can be reduced with this type of frame in a 50-year lifecycle which is more than 5% of the total CO2 production of the building. The methodological approach used in this research introduces a novel way for decision-makers to consider the sustainability criteria in the design stage

Limitations of spinal anesthesia for patient and surgeon during percutaneous nephrolithotomy

Purpose: To evaluate the intraoperative pain score of patients who undergo percutaneous nephrolithotomy under spinal anesthesia and to evaluate surgeons' and patients' convenience with this type of anesthesia. Materials and Methods: PCNL cases who were performed by two endourology fellows under spinal anesthesia during June to July 2014 were included. Spinal anesthesia was performed using injection of 0.25mg/kg bupivacaine 0.5 in the intrathecal space. All procedures were performed with the patient in the prone position. Stone access was made by using fluoroscopic guidance, and the tract was dilated using a single-stage technique. Visual analogue pain score was used to assess patients' pain during operation, immediately after, and 2 hours later. Results: 50 patients were enrolled during the study period. Visual analogue pain score of 10 and 8 were observed in 5 and three patients respectively. In two patients the operation was terminated because of patient anxiety and pain. In another patient a second access was not obtained to remove a staghorn stone because of patient's agitation. Gross agitation was observed in six patients. Apart from flank pain, intraoperative pain was felt in the flank, scapula, abdomen and/or chest. Conclusion: Spinal anesthesia does not provide enough analgesia for the patient in a limited frequency of percutaneous nephrolithotomy operations. We could not find statistically significant predictors of insufficient analgesia based on patients' demographics, stone characteristics or access location. © 2017, Urology and Nephrology Research Centre

Evaluation of Silicon Supplementation for Drought Stress under Water-Deficit Conditions: An Application of Sustainable Agriculture

Drought is a key abiotic stress that confines agriculture development worldwide. Silicon (Si) is commonly considered to be a valuable element for resistance against drought and for sustainable agriculture. To investigate the morpho-physiological and biochemical characteristics of Gerbera jamesonii plants, a pot experiment was conducted under greenhouse conditions and exposed to water stress (60% FC) and well-watered (100% FC) conditions. Foliar application of Si was carried out after ten days (48 days after sowing) of drought treatment and was repeated weekly, while well-water was regarded as control. Water deficiency significantly abridged the morphological attributes, pigments, and stress-related metabolites and negatively affected the photosynthetic apparatus in drought-stressed gerbera plants. However, Si supplementation by 40 mg L-1 produced increased leaf area (31%), stem length (25%), flower diameter (22%), plant fresh biomass (17%), total chlorophyll (48%), and concentration of carotenoids (54%) in water-stressed plants. Similarly, the accretion of a total free amino acid (41%) and the activities of peroxidase, catalase, superoxide dismutase, ascorbate peroxidase, glycinebetaine, total soluble proteins, total free proline, and malondialdehyde were enhanced by 44%, 31%, 53%, 33%, 330%, 61%, 51%, and 66%, respectively, under drought stress in comparison with control conditions. Meanwhile, the photosynthetic rate (89%), the transpiration rate (12%), and stomatal conductance (55%) were significantly enhanced in water-deficit gerbera leaves with Si supplementation. This study proposes that the foliar application of Si is a viable and convenient method of improving the performance of elegant gerbera flower plants in regions of the world that are facing severe water deficiency

Hydrometeorology: Review of Past, Present and Future Observation Methods

Hydrometeorology aims at measuring and understanding the physics, chemistry, energy and water fluxes of the atmosphere, and their coupling with the earth surface environmental parameters. Accurate hydrometeorological records and observations with different timelines are crucial to assess climate evolution and weather forecast. Historical records suggest that the first hydrometeorological observations date back to ca 3500 BC. Reviewing these observations in the light of our modern knowledge of the dynamic of atmospheres is critical as it can reduce the ambiguities associated to understanding major fluctuations or evolutions in the earth climate. Today, the ambiguities in hydrometeorological observations have significantly improved due to the advances in monitoring, modeling, and forecasting of processes related to the land-atmosphere coupling and forcing. Numerical models have been developed to forecast hydrometeorological phenomena in short-, medium- and long-term horizons, ranging from hourly to annual timescales. We provide herein a synthetic review of advances in hydrometeorological observations from their infancy to today. In particular, we discuss the role of hydrometeorological records, observations, and modeling in assessing the amplitude and time-scale for climate change and global warming