Flow General Inc., of McLean, reported a second-quarter loss of $636,000 (7 cents per share) for the three months ended Dec. 31. The applied sciences and biotechnology firm lost $1.5 million (18 cents) in the same period of the previous year.

Second-quarter sales were $36.1 million, up from $33.5 million the year before.

For the six months ended Dec. 31, Flow reported a loss of $2.6 million (29 cents), down from $9.4 million ($1.12) in the first half of the preceding fiscal year. Sales were $69.1 million, up from $65.3 million the year before.

* Cerberonics Inc. reported second-quarter profits of $499,000 (33 cents), up 29 percent from $387,000 (24 cents) for the same period a year before.

Sales for the quarter dropped to $10.8 million, compared with $11.2 million the year before.

For the first six months of its fiscal year, the firm reported earnings of $884,000 (59 cents), up 20 percent from $734,000 (44 cents) the year before. Sales declined to $19.1 million from $20.6 million the year before.

Cerberonics, based in Bailey's Crossroads, provides defense-related engineering, analytical and technical support services to the federal government. It attributed the earnings increase to improved cost control and blamed the revenue decrease on the expiration last year of a logistics contract.