ET Intelligence Group: Shares of most listed wire and cable makers have lost 3-11% in the past two trading sessions amid concerns over the impact of Aditya Birla Group's foray into the sector under the brand Ultravolt. The entry of a well-funded company with a focus on strengthening pan-India distribution is expected to intensify competition in the retail segment, which is currently dominated by Polycab Industries, Havells India, KEI Industries, and RR Kable.On the other hand, companies catering to the mid-to-extra high voltage segments including Diamond Power Infrastructure are likely to show lesser impact given higher entry barriers due to…