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Continuously increasing demand for plant and animal products causes unsustainable depletion of biological resources. It is estimated that one-quarter of sharks and rays are threatened worldwide and although the global fin trade is widely recognized as a major driver, demand for meat, liver oil, and gill plates also represents a significant threat. This study used DNA barcoding and 16 S rRNA sequencing as a method to identify shark and ray species from dried fins and gill plates, obtained in Canada, China, and Sri Lanka. 129 fins and gill plates were analysed and searches on BOLD produced matches to 20 species of sharks and five species of rays or – in two cases – to a species pair. Twelve of the species found are listed or have been approved for listing in 2017 in the appendices of the Convention on International Trade in Endangered Species of Fauna and Flora (CITES), including the whale shark ( Rhincodon typus ), which was surprisingly found among both shark fin and gill plate samples. More than half of identified species fall under the IUCN Red List categories ‘Endangered’ and ‘Vulnerable’, raising further concerns about the impacts of this trade on the sustainability of these low productivity species.

Surgery is a core element of the clinical practice of gynaecology. Bonney's Gynaecological Surgery has been a firm favourite for gynaecological surgical practice since 1911. Specifically tailored for trainees in obstetrics and gynaecology, the text focuses on the most commonly performed procedures. The 12th edition will include a colour photo section. With greater emphasis on fundamental clinical skills and major updates on laparoscopic and robotic surgery, this classic text will be brought right up to date for the current trainee or junior consultant physician. Each chapter follows a consistent plan, guiding the reader through each procedure from anatomy and indications to post-op considerations and complications. The text is also accompanied by surgical illustrations of unparalleled quality, ensuring that this volume will remain a valuable resource for all clinicians specializing in gynaecological surgery.

It has long been held as conventional wisdom that urogenital fistulae in low-income and middle-income countries are almost exclusively of obstetric aetiology, related to prolonged neglected obstructed labour, whereas those seen in high-income countries are largely iatrogenic in nature. There is, however, a growing perception amongst those working in the field that an increasing proportion of urogenital fistulae in low-income and middle-income countries may be iatrogenic, resulting from caesarean section. Recent studies suggest that adverse patterns of care may also be emerging in high-income countries; an increase in the risk of both vesicovaginal and ureterovaginal fistulae following hysterectomy has been reported, concurrently with the reduction in overall use of the procedure. These apparent secular trends are discussed in the context of evolution of practice, teaching and training in obstetrics and gynaecology.

In 2005, noted historian Nancy Bernkopf Tucker advanced the thesis that President Richard M. Nixon and National Security Advisor Henry Kissinger viewed Taiwan as an expendable asset in their rush to promote Sino-American normalization, resulting in the administration conceding more than necessary in disregard for Taiwan's future or status. This article examines documents declassified since Tucker's study to argue that this interpretation is no longer tenable. Nixon and Kissinger applied to their Taiwan policy a set of principles remarkably consistent with their broader views on foreign policy, namely an emphasis on peoples directly involved in conflicts undertaking gradual, peaceful changes, while maintaining in the interim some form of security arrangement to maintain peace. Moreover, both Nixon and Kissinger understood the myriad benefits of the u.s. relationship with the Republic of China in advancing American interests and maintaining credibility in a volatile world, and, in fact, did consider the future status of Taiwan and its government. This culminated in the Kissinger-Zhou Enlai discussions in 1971 where the former deftly defended, to the extent possible, a principled commitment to Taiwan. Ultimately, the administration's insistence on establishing rapprochement with Beijing did not mean that Washington simply would cave to every Chinese demand. Taiwan was not expendable.

Introduction and hypothesis Mid-urethral tape procedures brought a paradigm shift in surgery for stress incontinence; little research into the development and maintenance of surgical competence for the procedure exists. The hypothesis behind this study is that the  “learning curve” for retropubic mid-urethral sling procedures, judged by the surrogate of bladder perforation, is longer than previously thought. Methods This was a retrospective single-centre database and case note review of retropubic mid-urethral tape procedures. Unadjusted rates of bladder perforation, operating time, postoperative voiding difficulty, tape extrusion, and patient reported outcome were calculated; progress was evaluated using the cumulative sum method. Outcomes were assessed for 1 consultant, 2 subspecialty trainees (fellows), 7 advanced training skills module (ATSM) trainees (senior residents) and 6 core specialty trainees (residents) in years 4–7 of training. Results A total of 1,568 women were identified as having mid-urethral tape procedures; 568 (36 %) had additional procedures concurrently; 259 (20 %) were secondary procedures. The overall perforation rate for individual surgeons varied between 0 and 31 % and averaged 10.3 % amongst the core and ATSM trainees (a mean of 11 procedures), 4.5 % amongst the subspecialty trainees (a mean of 66 procedures) and 1.3 % for the consultant (1,284 procedures). The number of perforations for individual surgeons peaked at between 10 and 30 procedures undertaken. The number of cases performed to reach a target level of ≤5 % perforations varied between 20 and 80. Conclusions Whilst seductively simple in concept, mid-urethral tape procedures are not without risk; their inherently “blind” nature makes them difficult to teach. The “learning curve” to independent practice may be longer than previously considered.

Background INVESTIGATE-I (INVasive Evaluation before Surgical Treatment of Incontinence Gives Added Therapeutic Effect?) was a mixed methods study to assess the feasibility of a future randomised controlled trial of invasive urodynamic testing (IUT) prior to surgery for stress urinary incontinence (SUI) in women. Here we report one of the study’s five components, with the specific objectives of (i) exploring the cost-effectiveness of IUT compared with clinical assessment plus non-invasive tests (henceforth described as ‘IUT’ and ‘no IUT’ respectively) in women with SUI or stress-predominant mixed urinary incontinence (MUI) prior to surgery, and (ii) determining the expected net gain (ENG) from additional research. Methods Study participants were women with SUI or stress-predominant MUI who had failed to respond to conservative treatments recruited from seven UK urogynaecology and female urology units. They were randomised to receive either ‘IUT’ or ‘no IUT’ before undergoing further treatment. Data from 218 women were used in the economic analysis. Cost utility, net benefit and value of information (VoI) analyses were performed within a randomised controlled pilot trial. Costs and quality-adjusted life years (QALYs) were estimated over 6 months to determine the incremental cost per QALY of ‘IUT’ compared to ‘no IUT’. Net monetary benefit informed the VoI analysis. The VoI estimated the ENG and optimal sample size for a future definitive trial. Results At 6 months, the mean difference in total average cost was £138 ( p  = 0.071) in favour of ‘IUT’; there was no difference in QALYs estimated from the SF-12 (difference 0.004; p  = 0.425) and EQ-5D-3L (difference − 0.004; p  = 0.725); therefore, the probability of IUT being cost-effective remains uncertain. The estimated ENG was positive for further research to address this uncertainty with an optimal sample size of 404 women. Conclusions This is the largest economic evaluation of IUT. On average, up to 6 months after treatment, ‘IUT’ may be cost-saving compared to ‘no IUT’ because of the reduction in surgery following invasive investigation. However, uncertainty remains over the probability of ‘IUT’ being considered cost-effective, especially in the longer term. The VoI analysis indicated that further research would be of value. Trial registration ISRCTN. ISRCTN71327395 . Registered 7 June 2010.

In this paper, a computational fluid mechanics model is developed for full penetration laser welding of titanium alloy Ti6Al4V. This has been used to analyze possible porosity formation mechanisms, based on predictions of keyhole behavior and fluid flow characteristics in the weld pool. Numerical results show that when laser welding 3 mm thickness titanium alloy sheets with given laser beam focusing optics, keyhole depth oscillates before a full penetration keyhole is formed, but thereafter keyhole collapses are not predicted numerically. For lower power, lower speed welding, the fluid flow behind the keyhole is turbulent and unstable, and vortices are formed. Molten metal is predicted to flow away from the center plane of the weld pool, and leave a gap or void within the weld pool behind the keyhole. For higher power, higher speed welding, fluid flow is less turbulent, and such vortices are not formed. Corresponding experimental results show that porosity was absent in the melt runs made at higher power and higher welding speed. In contrast, large pores were present in melt runs made at lower power and lower welding speed. Based on the combination of experimental results and numerical predictions, it is proposed that porosity formation when keyhole laser welding may result from turbulent fluid flow behind the keyhole, with the larger the value of associated Reynolds number, the higher the possibility of porosity formation. For such fluid flow controlled porosities, measures to decrease Reynolds number of the fluid flow close to the keyhole could prove effective in reducing or avoiding porosity.

Repeated symptomatic urinary tract infections (UTIs) affect 25% of people who use clean intermittent self-catheterisation (CISC) to empty their bladder. We aimed to determine the benefits, harms, and cost-effectiveness of continuous low-dose antibiotic prophylaxis for prevention of recurrent UTIs in adult users of CISC. In this randomised, open-label, superiority trial, we enrolled participants from 51 UK National Health Service organisations. These participants were community-dwelling (as opposed to hospital inpatient) users of CISC with recurrent UTIs. We randomly allocated participants (1:1) to receive either antibiotic prophylaxis once daily (prophylaxis group) or no prophylaxis (control group) for 12 months by use of an internet-based system with permuted blocks of variable length. Trial and laboratory staff who assessed outcomes were masked to allocation but participants were aware of their treatment group. The primary outcome was the incidence of symptomatic, antibiotic-treated UTIs over 12 months. Participants who completed at least 6 months of follow-up were assumed to provide a reliable estimate of UTI incidence and were included in the analysis of the primary outcome. Change in antimicrobial resistance of urinary and faecal bacteria was monitored as a secondary outcome. The AnTIC trial is registered at ISRCTN, number 67145101; and EudraCT, number 2013-002556-32. Between Nov 25, 2013, and Jan 29, 2016, we screened 1743 adult users of CISC for eligibility, of whom 404 (23%) participants were enrolled between Nov 26, 2013, and Jan 31, 2016. Of these 404 participants, 203 (50%) were allocated to receive prophylaxis and 201 (50%) to receive no prophylaxis. 1339 participants were excluded before randomisation. The primary analysis included 181 (89%) adults allocated to the prophylaxis group and 180 (90%) adults in the no prophylaxis (control) group. 22 participants in the prophylaxis group and 21 participants in the control group were not included in the primary analysis because they were missing follow-up data before 6 months. The incidence of symptomatic antibiotic-treated UTIs over 12 months was 1·3 cases per person-year (95% CI 1·1–1·6) in the prophylaxis group and 2·6 (2·3–2·9) in the control group, giving an incidence rate ratio of 0·52 (0·44–0·61; p<0·0001), indicating a 48% reduction in UTI frequency after treatment with prophylaxis. Use of prophylaxis was well tolerated: we recorded 22 minor adverse events in the prophylaxis group related to antibiotic prophylaxis during the study, predominantly gastrointestinal disturbance (six participants), skin rash (six participants), and candidal infection (four participants). However, resistance against the antibiotics used for UTI treatment was more frequent in urinary isolates from the prophylaxis group than in those from the control group at 9–12 months of trial participation (nitrofurantoin 12 [24%] of 51 participants from the prophylaxis group vs six [9%] of 64 participants from the control group with at least one isolate; p=0·038), trimethoprim (34 [67%] of 51 vs 21 [33%] of 64; p=0·0003), and co-trimoxazole (26 [53%] of 49 vs 15 [24%] of 62; p=0·002). Continuous antibiotic prophylaxis is effective in reducing UTI frequency in CISC users with recurrent UTIs, and it is well tolerated in these individuals. However, increased resistance of urinary bacteria is a concern that requires surveillance if prophylaxis is started. UK National Institute for Health Research.