Infrastructure means the basic structure of an organization or system. A company's infrastructure would include all the fixed assets, i.e., the building, equipment, machinery and tools required to manufacture their product. Although people are not fixed assets they would be included in the company's infrastructure too.
Rarely a serious problem. Look-alikes: Jumping oak gall, tubakia leaf spot, oak leaf blister, other fungal leaf spots. Jumping oak gall Brown leaves appear on trees in the white oak group in late spring. Severe infections may cause the leaves to turn black, curl up and fall. On the underside are brown galls with the larva of a small wasp inside.
Christmas Cactus - leaves get limp and fall off. I have trouble with my Christmas Cacti every winter. I keep the plants outside all summer where they flourish. After bringing them in, they usually do well for a month or so, then I see leaves get limp and sometimes they appear to dry up and fall off. I water lightly ever couple weeks. My house is very dry - I have a woodstove. I do not see any pests.