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Climate change impacts, sustainable food production and conserve the natural sources and energy create the drive forces to create new techniques in agricultural systems pay more consideration to the environmental.The study was conducted during two successive seasons 2012/2013 and 2013/2014 at Central Laboratory for Agriculture Climate plastic house (CLAC), Agriculture ResearchCenter (ARC), Dokki,Gizagovernorate, Egypt. The main objectives of the study were alternating the natural fertilizers instead of synthetic chemical fertilizers, maximize the yield production and qualitybeside conserve the environmental and energy. The investigation studied the effect of different three rates of feldspar fertilizer (100%, 125%, 150%) from recommended dose, twoforms of feldspar (granule and fine powder fertilizer)compared to standard potassium sulfate 100% combined withtwo cultivars (Alhamma and Moralida)in pots culture on productivity and podquality of climbing snap bean (Phaseolus vulgarisL.) in factorial experiment grown under unheated plastic house. Vegetative growth (number of leaves, plant height, stem diameter and number of branches), chemical constituents of plant leaves (N, P and K), total yield per plantphysical quality of pods (pod diameter, pod length and pod weight), fibers (%) were recorded. The obtained results indicated that increasing the rate of feldspar from 100 to 150 % had no positive effect on the yield. Otherwise, using bothK-Granulee feldspar and K-fine feldsparat 100%gave the highest total yield per plant.Snap bean cv.Moralida recorded higher total yield per plant (16% more) than cv. Al-Hamma under unheated plastic house. The use of natural feldspar was more efficient on different scales (environment, economic, energy and etc.) than K-chemical fertilizer to match sustainable production of snap bean under plastic house. [ABSTRACT FROM AUTHOR]

Sustainable horticulture production, recycling organic wastes, mitigate climate change impacts and greenhouse gas emission and save natural resources under urban and rural areas are a serious issues need to create new strategies. Rooftop garden and vermicomposting technologies performed an integrated strategy to share in achieving resilience city. The study was conducted out during two successive winter seasons (2015 and 2016) under urban conditions at Central Laboratory for Agricultural Climate (CLAC), Giza, Egypt. The study investigated the use and the effect of vermicompost as an amendable substrate in different proportions (10 and 20% V/V) with sand: peat moss (1:1 V/V) and sand combined with two nutrient solution sources (chemical nutrient solution and vermi-liquid) with two EC levels (1 and 1.5 dS m-1) on lettuce yield under urban condition. Iceberg lettuce type cv. Robinson F1 hybrid was cultivated in split split plot design with three replicates. The study aimed to alternate or minimize the use of peat moss by vermicompost and chemical fertilizers by organic source via vermi-liquid to provide more sustainable production and mitigate climate change impacts via converting urban organic wastes through vermicomposting technology into vermicompost and vermi-liquid. Results revealed that using vermicompost as a substrate amendment combined with different substrates had a significant effect on lettuce yield through enhancing the physical and chemical properties of substrate and support plant nutrition. The use of chemical nutrient solution + EC level 1.5 dS m-1 + substrate sand: peat moss: vermicompost ((40: 40: 20% V/V) for producing the highest yield of lettuce under the investigation conditions. While for environmentally and safety, vermi-liquid + Ec level 1.5 dSm-1 + substrate sand: peat moss: vermicompost (40: 40: 20% V/V) was recommended. The study supported the micro and small scale urban farm to match the food security and safety needs via using vermicomposting outputs and simple substrate culture in top roof garden technique. Recycling urban organic wastes and mitigating greenhouse gases (GHG's) emission as well as sustainable food production need more efficient efforts and real contribution. Ecology food could be sustained under urban condition. [ABSTRACT FROM AUTHOR]

Urban horticulture has become one of the most important constitute actions to address poverty and fight against hunger, especially in the mega cities like Cairo, which suffering from limited availability of agricultural land as well as used in mitigating greenhouse gases (GHG's) and climate change mitigation and adaptation measures. The use of green roof technique via soilless culture systems and vermicomposting improve the efficiency of urban horticulture under the expected climate change conditions. The study was carried out during two successive winter seasons of 2014/2015 and 2015/2016 under green roof system condition at the Central Laboratory for Agricultural Climate, Agricultural Research Center, Egypt. The study aimed to optimize the use of local substrates (sand and rice husk) and provide vermicomposting technique for recycling the urban organic wastes through investigate different vermicompost rates (10, 20 and 30%) as a substrate amendment mixed with sand: rice husk (1:1 V/V) compared to peat moss : perlite (1:1 V/V) (control) combined with three different volume of pots (4, 6, and 8 L) on vegetative growth, yield and quality of celery and red cabbage. Physical and chemical properties of substrates, vegetative growth, yield characteristics and N, P and K contents of celery and red cabbage were determined. The physical and chemical properties of different substrate mixtures were affected by vermicompost implement rate. The obtained results indicated that increasing pot volume from 4 to 8 L of substrate led to increase the vegetative and yield of celery and red cabbage in reverse to the economic efficiency. The medium pot volume of substrate gave the highest economic yield of celery and red cabbage compared to the other volumes. Increasing the rate of vermicompost from 10 to 20% led to increase the vegetative and yield characteristics of celery and red cabbage while increasing up to 30% had a negative impact. Increasing the vermicompost rate from 10 to 30% led to increase the N, P and K contents of celery and red cabbage compared to the control treatment while increasing the pot volume from 4 to 8 L/plant decreased N, P and K contents of celery and red cabbage. The best vegetative growth and yield of celery were given by using sand + rice husk + vermicompost (40: 40: 20 V/V) in pot volume 8 L for producing more healthy, economically and environmentally food. The economic results had a different view point, pot volume 4 L/plant combined with vermicompost rate 10% followed in ascending order by 20% and pot volume 8 L/ plant combined with vermicompost rate 10% followed by 20% for celery and red cabbage, respectively. While the lowest economic use was given by 8 L/plant combined with peat + perlite substrate (control) in both of celery and red cabbage. [ABSTRACT FROM AUTHOR]

To investigate the effect of active roll stabilizer system performance on vehicle stability, it is needed to study the effects of varying speeds of the on-road vehicles under different wheel steer angle on the roll angle, side slip angle and yaw rate on the vehicle stability. For a safe drive, when a vehicle is cornering it should not lose its stability on road. In this paper the response of passive and active roll stabilizer vehicle systems are simulated and compared against each other. The results of the simulation model showed a significant influence of the vehicle speed on the vehicle stability under different wheel steer angles. [ABSTRACT FROM AUTHOR]

This paper presents a theoretical model for simulation of driving torque distribution control to improve off-road vehicle mobility on split adhesion conditions. The model is constructed and then validated with experimental test rig results. A MATLAB simulink modeling of an electronically controlled device is used to modulate the applied force over multi-plate clutches located between the automotive driven axle shafts and the stationary hub. On driving over split adhesion roads, the control device brakes the spinning axle wheel running over ground low adhesion side and accordingly biases more torque to the other wheel with good adhesion side. This would improve the vehicle off-road mobility and save the power losses on low adhesion wheels. The proposed control model had been validated with experimental results obtained from an experimental tests conducted on a specially designed and built test rig. Consequently, the proposed control system has been embedded within a full car theoretical model to predict the vehicle performance on split adhesion drive conditions. The results showed that the constructed simulink model is suitable for simulating the proposed controlled device for torque distribution after matching the simulation results with experimental test rig results. Moreover, the proposed control model could be implemented to improve the transmitted traction power to the road from a conventional deferential. [ABSTRACT FROM AUTHOR]

The ability of aquatic macrophytes to bioaccumulate toxic metals relative to the concentrations of these metals in wastewater has led to their use as phytoremediators. Lead (Pb) is among the most serious environmental contaminants. This study assesses the gibbous duckweed (Lemna gibba L.) as a bioaccumulator and bioindicator of Pb pollution. The plant recovery from a 12-d exposure period in terms of re-releases of Pb from its tissues, and recovery of pigmentation was monitored. Duckweed was exposed to Pb-contaminated water by adding PbCO3 at concentrations from 10 to 100 mg/L. At 2-d intervals, bioaccumulation, contaminant removal efficiency, pigment content, and bleaching were assessed. The efficiency of Pb removal after 12 d reached nearly 50% at the lowest Pb treatment (10 mg/L), but decreased at higher levels of Pb up to 100 mg/L. The highest bioconcentration factors (BCF) were achieved at low Pb treatment of 10 mg/L, which increased from nearly 200 mg/L after 2 d, to 943 mg/L after 12 d of exposure. Recovery from bleaching was around 50% for all photosynthetic pigments in plants exposed to 10-40 mg/L concentrations of Pb. The response of duckweed to Pb treatment and recovery from stress suggest its possible use as biosensor or biomonitor of Pb pollution, considering that active uptake, rather than low concentration gradient, is driving the absorption of Pb from the water medium. [ABSTRACT FROM AUTHOR]

Cervical ectopic pregnancy is implantation of an embryo into the cervical mucosa below the level of the internal os. Cervical pregnancy is an infrequent form of ectopic gestation both in naturally conceived pregnancies and even after assisted reproductive technology (ART). It accounts for less than 1% of all ectopic pregnancies. The Transvaginal ultrasonographic diagnosis rests upon empty uterus, trophoblastic invasion of the cervix below the internal os and enlarged barrel shaped cervix containing a gestational sac present below the level of internal os. Early detection is desirable in order to plan the management early and to avoid serious and often life threatening complications. Management options vary and depend on the gestational age at diagnosis, general condition of the patient and woman's desire to maintain fertility. Medical treatment with methotrexate is the therapy of choice in early gestation with hemodynamically stable patient. Surgical intervention is indicated in late gestation, unstable cases or failed medical treatment. [ABSTRACT FROM AUTHOR]

The off-road vehicles have much higher rolling resistance due to tire sinkage. This paper presents a proposed system for automatic adaptation for tire inflation/deflation, according to operating conditions. The tire inflation pressure is manually changed by the driver to some prefixed pressure values. The proposed control system is based on calculating the instantaneous wheel slip ratio. As the slip ratio increases, the tire pressure decreases automatically to increase the contact area and to decrease the dynamic sinkage and vice versa. An algorithm for the control strategy is developed. The proposed system provides a continuous monitoring of tire pressures inside the tire and then to inflate/deflate according to terrain types. The results show that a low inflation pressure has a considerable effect on the net traction ratio where it improves the performance by 20% and the buffed tire has a better traction than lugged tire on sand. [ABSTRACT FROM AUTHOR]

This paper presents the effect of the suspension working space, body displacement, body acceleration and wheel displacement for the non-controlled suspension system (passive system) and the controlled suspension system of a quarter car model (semi-active system), and comparison between them. The quarter car passive and semi-active suspension systems are modelled using Simulink. Proportional Integral Derivative controllers are incorporated in the design scheme of semi-active models. In the experimental work, the influence of switchable damper in a suspension system is compared with the passive and semi-active suspension systems. [ABSTRACT FROM AUTHOR]

This study was carried out during 2013-2014 and 2014-2015 seasons at a private farm located at Tokh district, Qalubia Governorate. Strawberry fruits ˝festival cultivar˝ to study the effect of active (7.5% O2 +15% CO2 or 10% O2 +10% CO2) and passive modified atmosphere packaging (MAP) on preserving the quality parameters and extend the shelf life of fruits during storage at 0˚C plus shelf life at 10˚C.The results showed that active MAP inhibit the weight loss and decay percentage, maintained fruit texture, ascorbic acid, titratable acidity (TA) and decrease in color development during storage and shelf life. Passive MAP was less effective in reducing the loss of fruits texture, TA and ascorbic acid content. Untreated MAP (control) gave the highest values of weight loss and decay percentage and lowest values of texture, becoming more red and poor appearance after 15 days of storage at 0˚C + 2 days at 10˚C. The results showed also that the optimum gas composition of MAP tests for strawberry was 7.5% O2 +15% CO2. No decay was observed in active MAP at 7.5% O2 +15% CO2 during the storage period plus shelf life. Furthermore, it also retarded texture, color, titratable acidity and ascorbic acid content. Finally, the study concluded that storage of strawberry fruits at active MAP of 7.5% O2+ 15% CO2 improved storability of fruits, and maintained fruit quality and gave fruits with good appearance till of 15 days at 0˚C + 2 days at 10˚C without decay. The shelf life of strawberry after harvest can be extended to 3 days at 0˚C + 2 days at 10˚C by this treatment. [ABSTRACT FROM AUTHOR]