CONTENTS 1
1．The Sex Change of Fish 1
2．Spider 6
3．The Asian Cockroach 11
4．The Ozone Problem 15
5．The Greenhouse Effect 20
6．The Treatment of Waste Water 24
7．Polar Bears ard Solar Heating Systems 27
8．The Utilization of Ocean Energy 35
9．The Superconducting Supercollider 40
10．The Effects ofthe Chernobyl Accident 46
11．Space Exploration 52
12．An Unusual Planet 59
13．The Mars Observer 64
14．The Markarian 348 Galaxy 68
15．A Wonderland in the Atlantic Ocean 73
16．The Temperature of the Center of the Earth 77
17．The Cause of Earthquakes 80
18．The Great Changes of the Surface of the Earth 85
19．New Discoveries in Antarctica 98
20．The Earliest Tools with Handles 103
21．Promising Ways of Controlling Weeds 106
22．Groundnuts（1） 111
23．Groundnuts（2） 115
24．Small Farm Grain Storage 119
25．The Prediction of the World Population 123
26．The Fear of AIDS 126
27．The Only Effective Weapon in Fighting AIDS 132
28．An AIDS-Fighting Protein 137
29．An AIDS-Fighting Drug 141
30．The Early Discovery of Cancer 145
31．A Cancer-Fighting Protein 151
32．The Proper Use of Vitamins 155
33．Home Health Tests 159
34．Passive Smoking 164
35．Osteoporosis 170
36．The Examination of the Prostate 174
37．Depression 177
38．Parkinson's Disease 181
39．Down's Syndrome 186
40．Listeriosis 190