FORT WORTH -- A Fort Worth woman found slain inside her Fort Worth apartment in December 2011 had been strangled with so much pressure "that it damaged everything all the way back to her spine," the doctor who performed her autopsy testified Thursday.Dr. Marc Krouse said while he determined Jo Beth Marchand died from ligature strangulation, the woman also had blunt trauma to her head, had been struck hard enough in the nose to fracture cartridge and had a number of bruises on her body.Krouse's description of Marchand's injuries came during the second day of testimony in James Wesley Brooks Jackson's capital murder trial in State District Judge Scott Wisch's court.Jackson is accused of killing Marchand while in the course of sexually assaulting her and burglarizing her home. Friends found Marchand's body Dec. 2, 2011.Krouse testified that Marchand had injuries to her vaginal area indicative of sexual assault.He said he also found chemical burns on her thighs that occurred sometime after her death."It could be almost anything. Chicken soup could probably do that," Krouse said."What about household cleaners?" asked Sheila Wynn, who is prosecuting the case along with Bryan Hoeller."Yes," Krouse replied.Witnesses have testified that a green towel found near Marchand's body was damp and smelled of household cleaner, suggesting that Marchand's killer may have tried to clean up evidence of the crime.Sundaye Lopez, a forensic scientist with the Fort Worth police crime lab, testified that swabs she tested from a rape kit tested positive for blood but not seminal fluid. She testified that the absence of seminal fluid, however, does not rule out that sex occurred. Explanations, she said, could be that ejaculation did not occur, a condom was used, or cleaning was done to remove such fluids.A DNA analyst with the University of North Texas Center for Human Identification testified that Jackson could not be excluded as of one or at least two minor contributors to a mixed DNA profile found on a blood-stained cushion cover.A DNA analyst with Cellmark Forensics in Dallas then testified that DNA profiles derived from four hairs found on a blanket and one hair located on a comforter matched Jackson.