Los Angeles-based Spark Networks Inc. was this week’s biggest mover. The niche-focused online site operator gained 42 percent to end at $1.35. Guess was also among this week’s biggest movers. The Los Angeles-based clothing brand and retailer rose 22.34 percent to end at $15.66. Temple City-based Fulgent Genetics was this week’s biggest loser, dropping 11.22 percent to end at $5.22.