When the guard honey bees, Apis mellifera L., form a clump at the hive entrance or on the flight board, the oriental hornet, Vespa orientails L., either creeps toward the clump or hovers over it in order to take a bee. Once the hornet creeps, only few bees facing the hornet become alert, rock their heads and antennae, open their wings, and take a posture of defense. The rest of the clump stays listless without any signal of concern. However, the clump stays dense and the defending bees do not detach themselves neither from the rest of the clump nor from each other. For this reason, it is very difficult for the hornet to grab a bee unless the latter makes a “mistake” by detaching herself from other adjacent bees. If the hornet grabs such a bee, the other defending bees will not attack the hornet to free that bee even when the latter is one centimeter from the others. The defending bees can capture the hornet only when the latter grabs one of them which stands very close to the others. The hornet seems very “aware” of such a situation; hence she seldom becomes a captive. On the other hand, hovering over the clump makes it easier for the hornet to grab a bee. The hovering puts all the clump, rather than part of it, on alert. If the hornet is persistent, which is not often the case, then the clump will no longer be dense. The bees will panicly disperse all over the flight board; hence the hornet can find a detached bee and grabs it easily. The hornet also waits on wing in front of the hive to capture an outgoing or incoming flying bee but the latter usually maneuver to escape. Also, foraging bees reduce their activity during main hours of hornet presence. Among the main factors reducing the hornet impact are the continuous chasing of hornets to each other and the non-persistent attempts of the hornets when they attack bee clumps.
The finite element method has been used in this paper to investigate the behavior of precast reinforced concrete dapped-ends beams (DEBs) numerically. A parametric investigation was performed on an experimental specimen tested by a previous researcher to show the effect of numerous parameters on the strength and behavior of RC dapped-end beams. Reinforcement details and steel arrangement, the influence of concrete compressive strength, the effect of inclined load, and the effect of support settlement on the strength of dapped-ends beams are examples of such parameters. The results revealed that the dapped-end reinforcement arrangement greatly affects the behavior of dapped end beam. The failure load decreases by 25% when
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Thrust blocks and restraint joints are the two most popular methods of counteracting the thrust force that generated at pipe fittings (bends, Tee, wye, reducers, dead ends, etc…). Both systems perform the same function, which is to prevent the joints from separating from the pipes. The aim of the study is to review previous studies and scientific theories related to the study and design of thrust blocks and restraint joints to study the behavior of both systems under thrust force and to study the factors and variables that affect the behavior of these systems. The behavior of both systems must be studied because they cannot be abandoned, as each system has conditions whose use is more feasible, scientific, and economic
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Drug –induced nephrotoxicity is an important cause of renal failure. Aminoglycoside antibiotics, such as amikacin, which causes ototoxicity and nephrtotoxicity as a main side effects, this is focused on the use of natural materials as antioxidants against the toxic oxidative action that exert a cell damaging effect. The most important one of these materials is the honey. The aim of this work is to evaluate the antioxidant effects of honey against amikacin – induced nephrotoxicity.18 albino rats divided into 3 groups (6 rats per each group), group 1 received I.P daily dose of normal saline (control), group 2 received (35 mg/kg/day) I.P dose of amikacin ,and group 3 received (35mg/kg/day) of amikacin I.P dose in combina
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The city suffers from the weakness of the civil defense to provide services where there are clusters of residential Guy covered services for that requires the study of the geographic distribution of the civil defense centers in Baghdad care great because they take care of Protect the population and their own property and protect state institutions. Through a review of the problems faced it is expected that this study will help decision-makers to take appropriate steps to develop this service core
A protocol has been developed for micropropagation of Arachis hypogea L. under in
vitro conditions. Nodal explants gave rise to multiple shoots when cultured on MS medium
supplemented with different concentrations of BA (benzyladenine) with Kin (Kinetin) or GA3
(gibberellic acid). The highest response of shoot multiplication was obtained in MS
containing 1.5 mg.l¯¹ BA and 0.5 mg.L¯¹ Kin. The regenerated shootlets were rooted on MS
(Murashige and Skoog) basal medium with different concentrations of IBA (indolbutyric
acid) and IAA (indol acetic acid). The highest response of rooting was achieved with IBA at
0.05 + IAA at 0.05 mg.L¯¹. The maximum frequency of rooting and highest number of roots
This work presents a five-period chaotic system called the Duffing system, in which the effect of changing the initial conditions and system parameters d, g and w, on the behavior of the chaotic system, is studied. This work provides a complete analysis of system properties such as time series, attractors, and Fast Fourier Transformation Spectrum (FFT). The system shows periodic behavior when the initial conditions xi and yi equal 0.8 and 0, respectively, then the system becomes quasi-chaotic when the initial conditions xi and yi equal 0 and 0, and when the system parameters d, g and w equal 0.02, 8 and 0.09. Finally, the system exhibits hyperchaotic behavior at the first two conditions, 0 and 0, and the bandwidth of the chaotic
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A Laced Reinforced Concrete (LRC) structural element comprises continuously inclined shear reinforcement in the form of lacing that connects the longitudinal reinforcements on both faces of the structural element. This study conducted a theoretical investigation of LRC deep beams to predict their behavior after exposure to fire and high temperatures. Four simply supported reinforced concrete beams of 1500 mm, 200 mm, and 240 mm length, width, and depth, respectively, were considered. The specimens were identical in terms of compressive strength ( 40 MPa) and steel reinforcement details. The same laced steel reinforcement ratio of 0.0035 was used. Three specimens were burned at variable durations and steady-state temperatures (one
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The purpose of this article is to identify and evaluate the importance of birds of the genus Merops (European Bee-eater -Merops apiaster and Blue-cheeked Bee-eater -Merops persicus) in Uzbekistan, as well as to develop recommendations aimed at solving some problems associated with its conservation. As a result of the study, in the aspect of biocenotic relations, the natural significance of these species was revealed. The economic value is determined and analyzed in beekeeping farms. From the study of the remains of food contained in the stomachs, throats and nests of M.apiaster, a preliminary list of the main species of the food spectrum has been compiled. Based on the bioacoustic repellent "Korshun-8"
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Background: ?-L-Fucose is a methyl pentose sugar similar to L-galactose except for the loss of alcohol group on carbon number 6. The objective of this study is to evaluate the biochemical and antioxidant effect of intracrevicular injection of fucose into rabbits periodontium, throughout measuring the levels of total protein (TP), total fucose (TF), protein bound fucose PBF) , Malondialdehyde (MDA) , and vitamin C in sera of fucose injected rabbit groups. ) Materials and Methods: The existing study was carried out on 55 male rabbits and were divided randomly into three groups ; first group was injected with 50µl of 150mM fucose solution into gingival sulcus ; second group was injected with 50 µl of normal saline ; while the third group was
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