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The properties of Extra Low Interstitials (ELI) Ti6Al4V components fabricated via the laser-based powder bed fusion (L-PBF) process are prone to variation, particularly throughout a powder reuse regime. Interstitial pick-up of interstitial elements within the build chamber during processing can occur, most notably, oxygen, nitrogen, and hydrogen, which can impair the mechanical properties of the built component. This study analyses ELI Ti6Al4V components manufactured by the L-PBF process when subjected to a nine-stage powder reuse sequence. Mechanical properties are reported via hardness measurement and tensile testing. Results showed that from 0.099 wt.% to 0.126 wt.% oxygen content, the mean hardness and tensile strength increased from 367.8 HV to 381.9 HV and from 947.6 Mpa to 1030.7 Mpa, respectively, whereas the ductility (area reduction) reduced from around 10% to 3%. Statistical analysis based on the empirical model from Tabor was performed to determine the strength-hardness relationship. Results revealed a significant direct relationship between tensile strength and Vickers hardness with a proportionality constant of 2.61 (R-square of 0.996 and p -value of 6.57 × 10 -6 ).

We report a case of idiopathic spontaneous intraperitoneal haemorrhage (ISIH) in a 31-year-old patient at 37 weeks gestation in her second pregnancy. The patient presented to the labour ward with abdominal pain and uterine contractions. The initial complain was of sudden onset, severe sharp pain in left iliac fossa. She started having uterine contractions within 30 min of her presentation. Examination confirmed early labour with a footling breech presentation. Urgent caesarean section was performed that confirmed peritoneal bleeding of unknown origin with safe delivery of the baby. Mother and baby were safely discharged on day 5. 'Abdominal apoplexy' (ISIH), is a rare obstetric emergency with increased risk of fetal and maternal morbidity and mortality. With various clinical presentations as a possibility, diagnosis is challenging. High index of suspicion with prompt management of suspected cases can be pivotal life saving measure for the fetus and mother., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Given the paucity of published data regarding reaction rates in younger teenaged donors, we evaluated the reaction rates in all of our first time teenaged donors after New York Blood Center lowered the minimum permissible age for blood donations from 17 to 16 yr in 2005. The overall rates of vaso-vagal reactions in donors aged 16 to 19, and those resulting in syncope, occurring in 72,769 consecutive first time whole blood, 3,822 double red cell, and 777 platelet apheresis donations were calculated. They were correlated with age and compared to those found in donors aged 20-29. Separate rates were calculated by gender, age in yr, and donation type, and then compared to each other. The overall reaction rate among first time teenaged whole blood donors was 8.2% and was significantly greater than among plateletpheresis donors (4.0%; p <0.0002). The rate in female whole blood donors (10.0%) was significantly higher than in males (6.4%; p <0.0002). In male double red cell donors the overall reaction rate of 3.5% was significantly lower than that found in male whole blood donors (p <0.002). Among both male and female whole blood donors a significant correlation with decreasing donor age between 19 and 16 yr was found (r(2) = 0.981; p = 0.01) and (r(2) = 0.988; p = 0.006), respectively. We conclude that teenaged donors have increased reaction rates when compared to adults and the reaction rates increase with decreasing age. In addition, females have higher reaction rates than males. Finally, reaction rates associated with apheresis donations are significantly lower than those associated with whole blood donations.

Objective: We prospectively evaluated the risk of recurrence of anal sphincter disruption ("third degree tear") at next vaginal delivery and whether this complication was predictable by antepartum anal functional assessment., Study Design: Among 20,111 consecutive vaginal deliveries, where midline episiotomy was not performed, 342 (1.7%) third degree tears occurred, significantly more often in primiparae (2.9%) than multiparae (0.8%; P<0.001), all of whom underwent postpartum anal manometry and endosonography. Similar testing was performed antepartum and postpartum in 56 of 342 women who delivered again during the study period., Results: Eleven of 56 women were delivered by caesarean in next pregnancy. Third degree tears recurred in 2 (4.4%) of 45 women at next vaginal delivery. Both recurrent injuries occurred in asymptomatic women with normal antepartum manometry and following spontaneous deliveries and were satisfactorily repaired., Conclusion: Although anal sphincter injury was increased five-fold at next delivery, compared with all multiparae, 95% of women delivering vaginally after previous third degree tear did not sustain further overt sphincter damage. Recurrence was not predictable using pre-delivery anal physiology testing.

Objective: To assess the effects of delayed vs immediate pushing in second stage of labour with epidural analgesia on delivery outcome, postpartum faecal continence and postpartum anal sphincter and pudendal nerve function., Design: Prospective, randomised, controlled trial.Tertiary referral maternity teaching hospital., Population: One hundred and seventy nulliparous women randomised at full dilatation to immediate or delayed pushing., Methods: A total of 178 nulliparous women, all with continuous epidural analgesia, were randomised at full cervical dilatation, but before the fetal head had reached the pelvic floor, to either immediate pushing or 1 hour delayed pushing. Labour outcome was analysed and all women underwent postpartum assessment of anal sphincter function, including anal manometry. Those women who had a normal delivery underwent neurophysiology studies, while those women who had an instrumental delivery underwent endoanal ultrasound., Main Outcome Measures: Mode of delivery; altered faecal continence., Results: Ninety women were randomised to immediate pushing and 88 to delayed pushing. The spontaneous delivery rate was 56% (50/90) in the immediate pushing group and 52% (46/88) in the delayed pushing group. Mean duration of labour for the immediate pushing group was 427 minutes compared with 480 minutes for the delayed pushing group (P = 0.005). Eighty-four percent (76/90) of women in the immediate pushing group received oxytocin to augment labour, 21/76 (28%) in the second stage only. Eighty-one percent (71/88) of women in the delayed pushing group received oxytocin to augment labour, 22/71 (31%) in the second stage only. Fetal outcome did not differ between the two groups. Episiotomy rates were 73% and 69% in the immediate pushing and delayed pushing groups, respectively. 26% (23/90) of the immediate pushing group and 38% (33/88) of the delayed pushing group complained of altered faecal continence after delivery (NS). Manometry, ultrasound and neurophysiology studies did not differ significantly between the two groups. Overall, 55% of women after instrumental delivery had endosonographic evidence of damage to the external anal sphincter, while 36% of women after spontaneous delivery had abnormal neurophysiology studies., Conclusions: Rates of instrumental delivery were similar following immediate and delayed pushing, in association with epidural analgesia. Delayed pushing prolonged labour by 1 hour but did not result in significantly higher rates of altered continence or anal sphincter injury, when compared with immediate pushing.