Spider, the

Example 5.2 In a plunger-type injection moulding machine the torpedo has a length of 40 mm, a diameter of 23 mm and is supported by three spiders. If, during moulding of polythene at ITO C, the plunger moves forward at a speed of 13 mm/s, estimate the pressure drop along the torpedo and the shear force on the spiders. The barrel diameter is 25 mm. 

Spiders The component of the elevator that latches onto the hoisted item. 

Current is transferred to these meshes using distributors called spiders . The spiders have legs which distribute current to the mesh. The location of the spiders and the distribution of the anode and cathode spider legs has been developed via extensive calculation and trial to minimise the resistance of the spider/membrane/ mesh combination and to ensure that the resistance to current flow is equal across the whole membrane area, thus ensuring that there are no localised non-uniform current paths. The spiders are shown in Fig. 18.5 and the distribution pattern is shown in Fig. 18.6. 

Spiders use their venom to paralyze prey while they feast on the victim s body fluids. They primarily feed on insects and other spiders. The venom of about 200 out of the 30,000 species of spiders represents a risk to humans. The venom of spiders is a complex mixture of neuroactive proteins and other chemicals. Researchers have studied venoms both to understand the mechanism of their effects and in search of new drugs. If spiders were bigger they would be truly dangerous. Fortunately they are small, with only a very small amount of venom. Because of our much larger size we receive only a small dose, but when a spider bites another insect it delivers a very large dose indeed. 

Figure 2.2 Fear elicits both physical and emotional changes that are coordinated by the amygdala. When a person sees a fear-inducing stimulus (the spider), the image reaches the thalamus, which is relayed to the cortex and hippocampus and projected to the lateral nucleus of the am dala. Once the information reaches the amygdala s central nucleus, the thalamus, hippocampus, and cortex each produce a different fear response.

As regards receipt of PA from the male, there is also the interesting fact that the female herself, rather than only the eggs, may benefit from the acquisition. Female Utetheisa devoid of alkaloid (raised on pinto bean diet), if mated with a PA-laden male, become unacceptable to wolf spiders. The effect takes hold promptly and endures females are unacceptable to spiders from the moment they uncouple from the male and they remain unacceptable as they age. Chemical data showed that the female allocates the received PA quickly to all body parts (Gonzalez et al., 1999a Rossini et al., 2001). 

Mr. Plex nods and drops the ant. A cleaning spider, the size of a human hand, makes a twittering sound and starts toward the fallen ant. Bob points a... 

Lactrodectus mactans (lactrodectism is produced by a bite from the female spider). The female is larger than the male. It is noted for a black color that is shiny, with a rounded abdomen and a red hourglass mark on the ventral surface. The black widow spider produces neurotoxic venom. Alpha latrotoxin is the protein of the neurotoxin. 

Envenomation occurs subcutaneously due to the small biting apparatus of the spider. The Brown Recluse Loxosceles reclusa) spider, as its name implies, is found in secluded areas. Bites occur most frequently to the hands and arms while reaching into woodpiles or other well-protected areas. 

The Brazilian Wandering Spider has another well known common name. Banana Spider. The spider was given the name Banana Spider because there have been many cases where these spiders unintentionally hitched a ride on the banana boats heading for the United States and other countries. Though they can only survive a short time in cool weather. They thrive in the temperatures of the Southern United States and Mexico. 

Other organisms in which RNAi-mediated gene inactivation has been successful include Drosophila, many kinds of plants, zebrafish, spiders, the frog Xenopus, and mice. Although most other organisms do not appear to be as sensitive to the effects of RNAi as C. elegans, the method does have general use when the dsRNA is injected directly into embryonic tissues. 

Chitin, a polysaccharide similar to cellulose, is Earth s second most abrmdant polysaccharide (after cellulose). It is present in the cell walls of fungi and is the fundamental substance in the exoskeletons of crustaceans, insects, and spiders. The structure of chitin is identical to that of cellulose, except for the replacement of the OH group on the C-2 carbon of each of the glucose units with an -NHCOCH3 group. The principal source of chitin is shellfish waste. Commercial uses of chitin waste include the making of edible plastic food wrap and cleaning up of industrial wastewater. 

Salzberg and Dietz combined the lauryl chain with the rhodanate as lauryl rhodanate (United States patents 1,963,100 (1934) and 1,992,040 (1935). They found the lauryl derivative to be of uniformly high toxicity to several Insects. Against the red spider the lauryl derivative was more effective than the capric or nyristic rhodanates. On the other hand, the green chrysanthemum ajhid was killed almost as well by the 8-, 10-and 14- carbon rhodanates as by the 12-carbon one. 

Don t think that such things happen only in Greece. A similar incident occurred in Nova Scotia, Canada. A lady complained to her doctor of a buzzing in her ear — she feared that a fly had somehow flown in. Once again, a stunned physician came face to face with a spider. The Nova Scotia doctor initiated the usual treatment for bugs in the ear, squirting a little water into the ear canal. But the spider didn t take kindly to this at all. It jumped... 

Argiotoxins. Acylpolyamines from the venom of various Argiope spiders (Araneidae, round web spiders) The numbers after the names give the molec-... 

The samples used here were mainly draglines secreted from Nephila clavata spiders (Japanese golden web spider). The samples were automatically wound with a 5 cm X 10 cm rectangular frame covered with plastic tube, as shown in Fig. 4.42. The samples were then used for thermal, optical and aging measurements. 

Fig. 4.45 Electron microphotograph of a dragline from a Nephila clavata spider. The dragline consists of double filaments, (a) side view, (b) cross section view.

Fig. 4.53 Spider s weight (W) dependence of safety coefficient (5C) for the draglines secreted from N. clavata spiders. The SC is defined as the ratio of the elastic limit strength of the dragline to the spider s weight. The standard error in the observed values of elastic limit strength and cross section area was 5%.

D-Glucosamine can be obtained by hydrolysis of chitin, a polysaccharide found in the shells of lobsters and crabs and in the external skeletons of insects and spiders. The amino group of D-glucosamine as it occurs in chitin, however, is acetylated thus, the repeating unit is actually W-acetylglucosamine (Fig. 22.18). The glycosidic linkages in chitin are jS(l 4). X-Ray analysis indicates that the structure of chitin is similar to that of cellulose. 

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