ARCH Venture Partners announced Monday that it has promoted Kristina Burow and Paul Thurk to Partners at the firm. The venture capital firm invests in early-stage technology companies in the life, physical, and information sciences areas. Burow works out of ARCH's San Francisco office, and is a co-founder of Saaphire Energy. She has also been involved with Ensemble Discovery, Lycera, Achaogen, Kythera Biopharmaceuticals, Ikaria, and Quanterix. Thurk is in the firm's Austin offices, and was co-founder of Innovalight.