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Because of a lack of information about the rates of growth of aortic aneurysms, such rates in thoracic and abdominal aortic aneurysms were determined. One hundred seventy-one patients with atherosclerotic aortic aneurysm managed nonoperatively were followed up for more than 6 months with sequential computed tomography (CT). There were 211 aneurysms (thoracic aortic, 82; abdominal aortic, 129). The growth rates of thoracic and abdominal aortic aneurysms were 0.42 and 0.28 cm/y, respectively. Aneurysms at the aortic arch (n = 34) grew at a faster average rate (0.56 cm/y) than aneurysms arising at other levels, even when the rate was corrected for the initial diameter. It is recommended that thoracic aortic aneurysms, especially aortic arch aneurysms, be followed frequently with CT examination of size.

SUMMARY Echocardiographic examinations were performed in 60 professional bicyclists and control subjects to determine the effects of exercise on left ventricular hypertrophy and function. The athletes were separated by age into three groups: group I (n = 14), 20-29 years; group 2 (n = 17), 30-39 years; and group 3 (n = 29), 40-49 years.Echocardiograms showed enlargement of the left ventricular end-diastolic dimensions in all three groups compared with age-matched control groups (p < 0.001). Thickness of the interventricular septum and the left ventricular posterior wall was more prominent in group 3 of the athletes than groups I and 2 of the athletes and control group (p < 0.001). Resting left ventricular function evaluated with fractional shortening, ejection fraction and mean velocity of circumferential fiber shortening was significantly depressed in group 3 compared with the other groups. Moreover, 14% of group 3 subjects showed enlargement of left atrial dimension and T-wave inversion in the left precordial leads of the ECG. We conclude that left ventricular hypertrophy is an important ventricular adaptation in relatively young athletes. However, middle-aged athletes may be more susceptible to electrocardiographic abnormalities and prominent hypertrophy, and some may have slightly depressed left ventricular function.TRAINED ATHLETES often have bradycardia, systolic murmurs, radiographic evidence of cardiac enlargement, and a variety of electrocardiographic alterations.'-3 However, there has been controversy as to whether the athlete's heart is diseased, because the athletes usually do not have symptoms and remain active. Echocardiography provides a noninvasive and sensitive means of assessing cardiac dimension and function,4-7 and studies in relatively younger athletes have been reported.8 '3 However, few reports have noted the long-term effects of exercise on left ventricular hypertrophy and function in both young and middle-aged athletes. We used echocardiography to determine a pattern of hypertrophy and left ventricular function in professional bicyclists who had been under continuous training from youth to middle age.

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A new method for the total asymmetric synthesis of antitumor agent Taxol is described. Baccatin III, a complex carbon framework, is synthesized by way of B to BC to ABC ring construction. Further, a method of forming Taxol from baccatin III and a β‐amino acid is also demonstrated.

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Abstract-A novel robotic gripper with soft surfaces and underactuated joints was proposed. The soft surface was fabricated from a deformable rubber bag filled with incompressible fluid and a microgripper inside the fluid. A ratchet was installed at the underactuated joint so that the joint's rotation caused by contact with an environment, such as a supporting surface, can be preserved, and the actions of scooping and enveloping an object are realized. With one actuator, the gripper realized three modes i.e., parallel gripper, pinching, and enveloping. The range of graspable objects was wide and included soft, rigid, deformable, fragile, small (boundary length less than 30 mm), large (more than 80 mm long), thin (less than 0.5 mm) and heavy (more than 3 kg) objects.

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