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An investigation of the metastable unimolecular dissociation channels and decay fractions of Zr[sub x]C[sup +, sub y] is made using a reflectron time-of-flight mass spectrometer coupled with a laser vaporization source. Useful information pertaining to the decay channels is elucidated. Evidence pertaining to the source of the delayed atomic ion (a phenomenon only observed in the Met-Car system) as a fragmentation event in the acceleration region is also uncovered. [ABSTRACT FROM AUTHOR]

Objective:  Chronic hypertension is a known risk factor for the development of preeclampsia and obstetrical morbidity. However, recent risk estimates, particularly in the era of use of low-dose acetylsalicylic acid for preeclampsia prevention, are lacking. This study aimed to estimate the association between chronic hypertension and preeclampsia and other adverse pregnancy outcomes in a contemporary cohort of births spanning the period, since the introduction of a low-dose acetylsalicylic acid protocol. The secondary outcome was to estimate trends in preeclampsia and preterm birth among patients with chronic hypertension during the study period., Study Design:  A retrospective, population-based cohort study was conducted using the National Inpatient Sample Database to identify individuals discharged from hospitals in the United States following obstetrical delivery from 2014 to 2019. Pregnancies complicated by chronic hypertension were identified using ICD 9/10 (International Classification of Diseases 9th and 10th editions) codes. Multivariable logistic regression models were used to estimate the adjusted odds ratios for the association between chronic hypertension and adverse pregnancy outcomes compared with pregnancies not complicated by chronic hypertension. Temporal trends in preeclampsia and preterm birth among patients with chronic hypertension were estimated over the study period., Results:  Among 4,451,667 obstetrical delivery-related admissions, 139,556 (3.1%) included pregnancies complicated by chronic hypertension. Of these, 27,146 (19.4%) admissions included pregnancies with superimposed preeclampsia, compared with 222,351 (5.2%) of admissions that included pregnancies with preeclampsia without prior diagnosis of chronic hypertension. Pregnancies complicated by chronic hypertension were associated with 3.29 times the odds of preeclampsia compared with pregnancies without chronic hypertension (95% confidence interval: 3.22-3.36), but the odds of preeclampsia ( p -value for linear trend <0.0001) and preterm birth ( p -value for linear trend = 0.0001) in this subgroup decreased over the study period., Conclusion:  While the odds of preeclampsia are increased among pregnancies complicated by chronic hypertension, the odds of preeclampsia in this population have decreased over time., Key Points: · Pregnancies complicated by chronic hypertension are at significantly higher odds of preeclampsia.. · Recent guidelines have recommended low-dose acetylsalicylic acid for preeclampsia prevention in these pregnancies.. · In a nationwide cohort, the odds of preeclampsia among these pregnancies are decreasing over time.., Competing Interests: C.M.N. and J.S. report no conflicts of interest related to the content of this study. D.L.R. has received funding related to this topic from the National Health and Medical Research Council (Australia), the International Society of Ultrasound in Obstetrics and Gynecology (ISUOG), and Thermo-Fisher Scientific., (Thieme. All rights reserved.)

Objective: Our objective was to estimate the association between in vitro fertilization (IVF) pregnancy and adverse pregnancy outcomes during delivery hospital admission in a contemporary, nation-wide cohort of births in the United States., Study Design: This retrospective, population-based cohort study used the National Inpatient Sample database to identify patients discharged from the hospital following delivery from 2014 to 2019. IVF pregnancies were identified using the International Classification of Disease-Revision 9/10 codes. Crude and adjusted odds ratios of preterm birth and other clinically significant adverse pregnancy outcomes were evaluated using multivariable logistic regression models. Trends in preterm birth and multiple pregnancy were estimated over the study period. The contribution of multiple pregnancy to preterm birth in IVF pregnancy was estimated in a mediation analysis., Results: Among 4,451,667 delivery-related discharges, IVF pregnancies were associated with 3.25 times the odds of preterm birth (95% confidence interval [CI]: 3.05-3.46, p  < 0.001) compared with non-IVF pregnancy deliveries. Odds of preterm birth in IVF pregnancy delivery discharges decreased over the study period ( p -value for linear trend = 0.009). The proportion of multiple pregnancies decreased in IVF pregnancy delivery discharges but remained stable in non-IVF pregnancy deliveries. The proportion of the adjusted effect of IVF pregnancy on preterm birth mediated through multiple pregnancy was 67.6% (95% CI: 62.6-72.7%)., Conclusion: While the odds of adverse pregnancy outcomes are increased compared with non-IVF pregnancies, the odds of preterm birth and multiple gestation have decreased among IVF pregnancies in the United States., Key Points: · Pregnancies conceived by in vitro fertilization (IVF) are at significantly higher risk of multiple gestation, preterm birth, and other pregnancy complications.. · Recent guidelines for artificial reproductive treatments recommend single-embryo transfer in IVF.. · Using population-wide data, we demonstrate a significant gradual decline in the rates of preterm birth and other pregnancy complications following IVF in the last decade, mostly mediated by a reduction in multiple pregnancies.., Competing Interests: None declared., (Thieme. All rights reserved.)

Newcomer populations face many barriers accessing healthcare, including language barriers. Language-concordant care has been shown to enhance equity and optimize health outcomes for underserved populations. This paper describes a sexual and reproductive health (SRH) animation for newcomer populations. The animation was created collaboratively by the Department of Obstetrics and Gynaecology Global Health Unit, the Halifax Newcomer Health Clinic, and student volunteers. Integrating this animation into other healthcare settings may help improve inclusion, trust, and patient-centred care for newcomer patients. Institutions may also consider creating further SRH animations based on the needs of the patients they serve., Competing Interests: KW has received speaker honoraria from Merck. The remaining authors have no conflicts of interest to disclose., (© 2024 Sivakumar, Willows, Behroozan, Stairs; licensee Synergies Partners.)

Objectives: Surgical site infections (SSI) are common causes of postoperative morbidity at cesarean delivery (CD). The objective of this study was to compare the risk of SSI and other wound complications associated with different suture materials for subcuticular skin closure at CD., Data Sources: We searched Cochrane Library, MEDLINE, Embase, and Clinicaltrials.gov from inception to June 3, 2021, and limited our search to English, peer-reviewed, randomized controlled trials and cohort studies., Study Selection: Of 1541 titles identified, 4 studies met the selection criteria and were included. Studies were included if the population was pregnant individuals undergoing transverse incision primary or repeat, elective or emergent CD with subcuticular skin closure, and if outcomes related to SSI, wound seroma, hematoma, or dehiscence were reported. We completed the assessment using Covidence review management software., Data Extraction and Synthesis: Two authors independently reviewed studies and assessed the risk of bias using the Cochrane 'Risk of bias' tool for randomized trials (RoB 2.0) and the Cochrane Risk of Bias in Non-Randomized Studies-of Interventions (ROBINS-I) tools for cohort studies. We compared SSI risk and secondary outcomes of hematoma, seroma, and dehiscence between skin closure with monofilament (poliglecaprone 25 or polypropylene) versus multifilament (polyglactin 910) sutures using a fixed-effects meta-analysis. Statistical heterogeneity was estimated using the I 2 statistic. Monofilament sutures were associated with a reduced risk of SSI (RR = 0.71, 95% CI 0.52-0.98, I 2  = 0%) compared to multifilament sutures. There was no difference in the risk of secondary outcomes., Conclusion: Monofilament suture for subcuticular skin closure at CD was associated with decreased risk of SSI compared to multifilament suture., (Copyright © 2023 The Society of Obstetricians and Gynaecologists of Canada/La Société des obstétriciens et gynécologues du Canada. Published by Elsevier Inc. All rights reserved.)

Introduction and Hypothesis: Urinary incontinence (UI) is common in the postpartum period; however, most studies focus on the early postpartum period and assess prevalence at only one or two time points. We hypothesized that UI would be prevalent across the first 2 years postpartum. Our secondary objective was to evaluate risk factors for postpartum UI among a nationally representative, contemporary sample., Methods: This cross-sectional, population-based study used National Health and Nutrition Examination Survey (2011-2018) data for parous women within 24 months following delivery. Prevalence of UI, UI subtypes, and severity were estimated. Multivariate logistic regression was used to estimate adjusted odds (aOR) of UI for exposures of interest., Results: Among 560 postpartum women, prevalence of any UI was 43.5%. Stress UI was most common (28.7%), and most women (82.8%) experienced mild symptoms. There was no significant change in prevalence of UI across the 24 months following delivery (R 2  = 0.004). Individuals with postpartum UI tended to be older (30.3 ± 0.5 versus 28.8 ± 0.5 years) and had higher BMI (31.1 ± 0.6 versus 28.9 ± 0.6). In multivariate analysis, odds of postpartum UI were higher for women who had had a prior vaginal delivery (aOR 2.0, 95% CI: 1.3-3.3), prior delivery of a baby weighing 9 lb (4 kg) or more (aOR 2.5, 95% CI: 1.3-4.8), or who reported current smoking (aOR 1.5, 95% CI: 1.0-2.3)., Conclusions: During the first 2 years postpartum 43.5% of women report UI, with relatively stable prevalence over this period. This high prevalence supports screening for UI after delivery regardless of risk factors., (© 2023. The International Urogynecological Association.)

Introduction and Hypothesis: Patients with vaginal pessaries can learn to care for their pessary by themselves or they can have provider-led care, which requires more frequent follow-up visits. We aimed to understand motivations for and barriers to learning self-care of a pessary to inform strategies to promote pessary self-care., Methods: In this qualitative study, we recruited patients recently fitted with a pessary for stress incontinence or pelvic organ prolapse, and providers who perform pessary fittings. Semi-structured, one-on-one interviews were completed to data saturation. A constructivist approach to thematic analysis using the constant comparison method was used to analyze interviews. A coding frame was created following independent review of a subset of interviews by three members of the research team and this frame was used to code interviews and develop themes through interpretive engagement with the data., Results: Ten pessary users and four health care providers (physicians and nurses) participated. Three major themes were identified: motivators, benefits, and barriers. There were several motivators for learning self-care, including care provider advice, personal hygiene, and ease of care. Benefits of learning self-care included autonomy, convenience, facilitation of sexual relations, avoidance of complications, and decreased burden on the health care system. Barriers to self-care included physical, structural, mental, and emotional barriers; lack of knowledge; lack of time; and social taboo., Conclusions: Promotion of pessary self-care should focus on patient education about benefits and ways of mitigating common barriers while focusing on normalizing patient engagement in pessary self-care., (© 2023. The International Urogynecological Association.)

Importance and Objectives: Epidemiologic studies of incontinence largely focus on parous women, and there are limited data regarding nulliparous women. Our objectives were to evaluate risk factors for urinary incontinence among a nationally representative, contemporary sample of nulliparous women of all ages in the United States and to describe the prevalence and subtypes of urinary incontinence and nocturia in this population., Study Design: This cross-sectional, population-based study used the National Health and Nutrition Examination Survey cycles 2011-2018 to assemble a sample of nulliparous women 20-80 years old. Crude and adjusted odds ratios were estimated using multivariable logistic regression for the exposures of interest: body mass index (BMI), age, physical activity, prior hysterectomy, and current smoking. Prevalence of urinary incontinence and nocturia were estimated., Results: Among 1,603 nulliparous women, prevalence of any urinary incontinence was 29.38%. Prevalence of stress, urgency, and mixed urinary incontinence and nocturia, respectively, were 27.68%, 19.64%, 10.57%, and 58.95%. Women with a BMI ≥25 (calculated as weight in kilograms divided by height in meters squared; adjusted odds ratio [aOR], 1.57; 95% confidence interval [CI], 1.11-2.23), at least 45 years (aOR, 3.75; 95% CI, 2.31-5.83), and current smoking (aOR, 1.63; 95% CI, 1.07-2.49) had increased the odds of incontinence compared with women without these risk factors. When stress urinary incontinence (SUI) was considered alone, only women with a BMI ≥25 (aOR, 1.66; 95% CI, 1.20-2.31) and age at least 45 years (aOR, 3.17; 95% CI, 2.01-5.00) had increased odds of SUI compared with women without these risk factors., Conclusions: Urinary incontinence and nocturia are prevalent in nulliparous women, and age, elevated BMI, and current smoking may represent risk factors for incontinence in this population., Competing Interests: The authors have declared they have no conflicts of interest., (Copyright © 2022 American Urogynecologic Society. All rights reserved.)

Introduction and Hypothesis: Articles are getting published on the use of tissue adhesive for vesicovaginal fistula. The objective is to carry out a systematic review on their effectiveness and complications., Methods: A systematic review of the literature was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Two reviewers screened abstracts and full-text and extracted data independently. A narrative synthesis was conducted given the heterogeneity of studies., Results: A total of 1032 studies were identified after searching the database, and 14 articles were included in this systematic review. Of the 84 women included, 12 (14.3%) presented failure or recurrence of their fistula tract. The mean time of follow-up was 11.46 months. The average size of the fistula was 1.05 (range 0.1 to 3.9) cm. Most fistulas (81) included were vesicovaginal fistulas. Nine papers reported the usage of fibrin glue in which only three (6.5%) women reported recurrence of the fistula in a delay of 2 weeks to 26 months. The other studies used cyanoacrylate (14 women) and autologous fibrin injection from the patients' blood (31 women). No significant complications were reported. Complications reported were urinary tract infections in 3 women (3.6%), hematuria in 2 women (2.4%), overactive bladder symptoms in 6 women (7.2%) and septic pelvic thrombosis in one woman (1.2%)., Conclusions: Tissue adhesive appears to be a promising alternative for management of urogenital fistulas without reported important complications., (© 2022. The International Urogynecological Association.)

Importance: Apical suspension, including uterosacral ligament suspension (USLS) and sacrospinous ligament fixation (SSLF), is the standard of care at vaginal hysterectomy. Although the equivalence of anatomic and clinical outcomes after USLS and SSLF is established, comparing surgical complications specific to patients undergoing concurrent vaginal hysterectomy further informs decision making regarding operative approach., Objective: This study aims to compare complications in the first 30 days after surgery in patients undergoing USLS and SSLF at vaginal hysterectomy for pelvic organ prolapse., Study Design: This retrospective, population-based cohort study used the American College of Surgeons National Surgical Quality Improvement Program database to identify patients undergoing USLS or SSLF at vaginal hysterectomy for pelvic organ prolapse between 2012 and 2019. The primary outcome was a composite of surgical complications excluding urinary tract infection (UTI). Odds of the primary outcome, readmission, reoperation, and UTI were evaluated by multivariable logistic regression models., Results: Of 10,210 eligible patients, 7,127 patients underwent USLS and 3,083 patients underwent SSLF. Uterosacral ligament suspension was associated with a 25% lower odds of the composite complication outcome that excluded UTI compared with SSLF (adjusted odds ratio, 0.75; 95% confidence interval, 0.63-0.90). Urinary tract infection was the most common complication and occurred more commonly in patients undergoing USLS (6.5% vs 4.9%; adjusted odds ratio, 1.29; 95% confidence interval, 1.06-1.56). There was no significant difference in Clavien-Dindo class IV complications, readmission, or reoperation between approaches., Conclusion: Uterosacral ligament suspension was associated with a lower odds of complications excluding UTI compared with SSLF. Urinary tract infection was more common among patients having USLS. The odds of serious complications, readmission, and reoperation were low and comparable between groups., Competing Interests: The authors have declared they have no conflicts of interest., (Copyright © 2022 American Urogynecologic Society. All rights reserved.)

Introduction and Hypothesis: Identification and prompt management of postpartum urinary retention after vaginal birth is essential to minimize long-term morbidity. Obstetrical anal sphincter injuries (OASIS) have been identified as a possible risk factor for urinary retention. The objective of this study was to estimate the association between OASIS and postpartum urinary retention and compare the length of hospital stay and cost of admission between postpartum patients who experienced urinary retention and those who did not., Methods: We conducted a population-based, retrospective cohort study of pregnant individuals delivering singleton fetuses via vaginal birth in the United States using the National Inpatient Sample (NIS) database. Multivariate logistic regression models were used to estimate the odds ratio (OR) for the association between OASIS and postpartum urinary retention. Simple linear regression was used to compare means., Results: A total of 2,013,052 delivery admissions were included, which was representative of a population size of 10,065,253 utilizing the complex sampling design of the NIS database. 47,192 (2.34%) admissions sustained OASIS and 5,339 (0.27%) admissions experienced overt urinary retention. After adjusting for potential confounders, vaginal deliveries where OASIS occurred had 3.60 times the odds of postpartum urinary retention compared with vaginal deliveries where OASIS was not sustained (95% CI 3.26-3.97). Postpartum urinary retention was associated with an increased mean length of stay (2.94 vs 2.28 days, p<0.001) and 1.37 times the mean total cost of admission (US$22,946.38 vs US$16,758.85, p<0.001)., Conclusions: Obstetrical anal sphincter injuries are associated with increased odds of postpartum urinary retention compared with vaginal deliveries where OASIS did not occur., (© 2022. The International Urogynecological Association.)

Background: Germline pathogenic variants in BRCA1/2 have been established in hereditary breast and ovarian cancer (HBOC) syndrome and result in significantly elevated lifetime risk of ovarian cancer. Risk reduction interventions are presently the only effective means of improving survival and specialized counselling clinics have been established as an effective means of aiding this population in navigating complex decisions surrounding these interventions. This study sought to evaluate patient perceptions of a specialized counselling clinic for patients with HBOC Syndrome and referral patterns to this clinic., Methods: We completed a retrospective review of 200 patients with HBOC in Nova Scotia, Canada seen through Maritime Medical Genetics Services between 2006 and 2016. Data were collected on referral pattern to the Hereditary Gynaecologic Risk Reduction Clinic (HGRRC), demographics, health history, and uptake of risk-reducing interventions. Participants were invited to complete a questionnaire about their experience., Results: 156/200(78%) women were referred to HGRCC and 135/156 (85.9%) of those referred attended their appointment. 124/200 (62%) were over age 40 at the time of testing. The mean time from referral to HGRCC appointment was 134.68 days (SD 85.78). 85/135 (63%) underwent risk-reducing bilateral salpingo-oophorectomy following their HGRCC appointment. The questionnaire was completed by 94/188 (50.3%) women. Most participants found information received from genetics clinics (81/94; 91%) and genetic counsellors (87/94; 95%) most helpful in making choices around risk-reduction strategies. 83/94 (88%) participants felt they had sufficient information to make an informed decision., Conclusion: The majority of women with HBOC in Nova Scotia during the study period were referred to and counselled through HGRRC. Genetic counselling was found most valuable in risk-reduction decision making, which highlights the importance of a multidisciplinary team. Patients viewed this clinic as an effective care model to support informed choice about risk-reducing intervention., (© 2022. The Author(s).)

Importance: Overweight and obese women represent a growing share of pelvic floor reconstruction surgeons' practices. Determining perioperative risk specific to this population is essential to inform decision making regarding operative approach in this population., Objective: The aim of the study was to compare surgical complications among overweight and obese women undergoing apical compartment prolapse surgery by either minimally invasive abdominal or vaginal approach., Study Design: The American College of Surgeons National Surgical Quality Improvement Database was used to identify overweight and obese patients (body mass index ≥ 25) undergoing either minimally invasive sacrocolpopexy (MISC) or vaginal vault suspension (VVS) in the form of a sacrospinous vault fixation or uterosacral ligament fixation for pelvic organ prolapse from 2012 to 2019. Odds ratios for surgical complications, readmission, and reoperation were estimated using multivariable logistic regression., Results: Of 8,990 eligible patients, 5,851 underwent a VVS and 3,139 patients underwent MISC. There was a greater odds of any complication in the first 30 days following VVS (n = 608 [10.4%]) compared with MISC (n = 247 [7.9%]; odds ratio, 1.27; 95% confidence interval, 1.08-1.48) on multivariable analysis. Urinary tract infections (UTIs) were the most common complication and were more likely following VVS (112 (3.6%) versus 350 (6.0%), P < 0.001). When UTIs were excluded, there was no difference in complications between approaches (1.00; 95% CI, 0.82-1.22). There were no statistically significant odds of readmission, reoperation, or serious complications between approaches., Conclusions: Vaginal vault suspension may be associated with a higher odds of any complication compared with MISC in overweight and obese women, but the rate of serious complications, readmission, and reoperation are low, and approaches were comparable when considering complications other than UTI., Competing Interests: The authors have declared they have no conflicts of interest., (Copyright © 2022 American Urogynecologic Society. All rights reserved.)

Introduction and Hypothesis: Obstetrical anal sphincter injury (OASIS) is a common consequence of vaginal delivery in nulliparas and carries the risk of short- and long-term morbidity. The objective of this study was to estimate the association between the duration of the second stage of labour and OASIS risk., Methods: A population-based, retrospective cohort of nulliparas delivering singleton, vertex, non-anomalous fetuses at term in Nova Scotia, Canada, from 2005 to 2019, were identified using the Nova Scotia Atlee Perinatal Database. Poisson regression models were used to estimate risk ratios (RR) with robust 95% confidence intervals (CI) adjusting for confounding variables to investigate the association between the length of the second stage and OASIS in the entire cohort and in operative vaginal deliveries., Results: Of 36,662 participants, 7.6% sustained an OASIS (6.8% third-degree, 0.8% fourth-degree tear). The proportion of participants who sustained an OASIS increased over the study period. For each 30-min increase in the length of second stage, the OASIS risk increased by 11% (RR 1.11, 95% CI 1.10-1.12). When stratified by mode of delivery, second stage length ≥ 90 min was associated with an increased OASIS risk in spontaneous (RR 1.35, 95% CI 1.15-1.58) and vacuum-assisted vaginal deliveries (RR 1.42, 95% CI 1.11-1.81). In forceps-assisted vaginal deliveries, OASIS risk was increased, with shorter and longer durations of the second stage., Conclusion: Increasing length of the second stage of labour was associated with increasing risk of OASIS overall, but the association was heterogeneous between modes of delivery. Length of the second stage should be considered in counseling about OASIS risk., (© 2022. The International Urogynecological Association.)

Background The Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) is the patient-reported outcome (PRO) that is routinely used in clinical practice to monitor and measure disease activity in axial spondyloarthropathy (axSpA). BASDAI scores greater than four are thought to indicate active disease and require better control. Magnetic resonance imaging (MRI) is the most objective measure of disease activity in axSpA with its ability to pick up active inflammation both in the spine and sacroiliac joints. Previous studies have shown conflicting correlations between BASDAI and MRI, and therefore, there is the question of whether BASDAI is the best tool to monitor disease activity when it is subjective and potentially influenced by other patient factors. We, therefore, conducted a retrospective study to investigate the correlation between BASDAI and MRI in axSpA patients. Methodology Data were collected by retrospective analysis of axSpA patients attending University of Leicester (UHL) axSpA services. BASDAI scores were done within a year and closest to the time of MRI spine + sacroiliac joints were collected. The results prior to the initiation of biologic therapy were used. Data of one hundred and forty-nine patients were collected on their MRI results and BASDAI scores. Data were analysed using Statistical Package for the Social Sciences (SPSS) software and Pearson's chi-squared applied to assess the correlation between BASDAI and MRI findings. Results Out of one hundred and forty-nine patients, 61.7% had active sacroiliitis on their MRI, 57.7% had chronic sacroiliitis, 53% had active spinal inflammation, and 17.4% had other MRI findings of active disease. There was a significant correlation between active sacroiliitis and BASDAI (p=0.014), but similar results were not found with other radiological features. A significant correlation was also found with males having higher BASDAI scores compared to females (p=0.027). Conclusion This study demonstrates a statistically significant correlation between BASDAI and active sacroiliitis with those having higher scores more likely to have active disease on their MRI., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2021, Byravan et al.)

The COVID-19 pandemic resulted in changes to clinical clerkship delivery including decreased surgical exposure. The Department of Obstetrics and Gynaecology at Dalhousie University developed a novel, resident-led learning experience using a curated presentation of operative footage. This session aimed to improve medical students' orientation to the operative environment and supplement teaching on pelvic anatomy and gynaecologic surgery in response to decreased exposure during the COVID-19 pandemic. Medical students perceived this session as valuable and felt it improved their preparedness for the operating room. This initiative has the potential to improve medical student orientation to the operative environment., Competing Interests: Conflicts of Interest: None., (© 2021 Stairs, Amir, Vair; licensee Synergies Partners.)

Objective: Competency based medical education (CBME) requires novel approaches to surgical education. Significant investment has been made in laparoscopic simulation, which has been shown to foster skill development prior to patient encounters. However, research suggests variable voluntary use of these resources by residents, and little is known about the motivational factors that influence their utilization. The purpose of this study was to characterize factors that motivate residents to seek laparoscopic simulation experience outside of the formal curriculum., Design: We developed a questionnaire grounded in Expectancy Value Theory, an established psychological theory of motivation, by adapting validated measures to fit the study context. We conducted a cross sectional survey of Canadian obstetrics and gynecology residents., Setting: We invited residents enrolled in English-language obstetrics and gynecology training programs in Canada to participate., Participants: All residents engaged in clinical duties during Winter 2018 were invited to complete the questionnaire. Forty-four Obstetrics and Gynecology (Ob/Gyn) residents participated in the study., Results: Residents reported limited use of simulation resources and identified multiple barriers including lack of time, access, and supervision. They expressed concern about development of bad habits during independent practice, and simulation use was positively correlated with perceived utility. Compared to junior residents, senior residents reported greater enjoyment of laparoscopic surgery, less emotional costs, and higher self-efficacy for learning laparoscopy., Conclusions: Residents' perception of utility and barriers impede voluntary simulation use and overall use was limited. As programs undertake curricula redevelopment for CBME, mitigating barriers and improving perceived utility of laparoscopic simulation is vital to increase use and enhance skill development., Competing Interests: The authors have declared that no competing interests exist.

Competing Interests: Conflicts of interest: There are no conflicts of interest for any authors.

Identification of the fragment ion species associated with the ion reaction mechanism of triacetone triperoxide (TATP), a homemade peroxide-based explosive, is presented. Ion mobility spectrometry (IMS) has proven to be a key analytical technique in the detection of trace explosive material. Unfortunately, IMS alone does not provide chemical identification of the ions detected; therefore, it is unknown what ion species are actually formed and separated by the IMS. In IMS, ions are primarily characterized by their drift time, which is dependent on the ion׳s mass and molecular cross-section; thus, IMS as a standalone technique does not provide structural signatures, which is in sharp contrast to the chemical and molecular information that is generally obtained from other customary analytical techniques, such as NMR, Raman and IR spectroscopy and mass spectrometry. To help study the ion chemistry that gives rise to the peaks observed in IMS, the hardware of two different commercial IMS instruments has been directly coupled to triple quadrupole (QQQ) mass spectrometers, in order to ascertain each ion׳s corresponding mass/charge (m/z) ratios with different dopants at two temperatures. Isotope labeling was then used to help identify and confirm the molecular identity of the explosive fragment and adduct ions of TATP. The m/z values and isotope labeling experiments were used to help propose probable molecular formulas for the ion fragments. In this report, the fragment and adduct ions m/z 58 and 240 of TATP have been confirmed to be [C3H6NH·H](+) and [TATP·NH4](+), respectively; while the fragment ions m/z 73 and 89 of TATP are identified as having the molecular formulas [C4H9NH2](+) and [C4H9O2](+), respectively. It is anticipated that the work in this area will not only help to facilitate improvements in mobility-based detection (IMS and MS), but also aid in the development and optimization of MS-based detection algorithms for TATP., (Published by Elsevier B.V.)

We present a comparative study on the structural properties of the coinage metal icosamers Cu(20)(+/-), Ag(20)(+/-), and Au(20)(+/-). Using trapped ion electron diffraction measurements in combination with density functional structure calculations we find distinct structural differences depending on the cluster material and the charge state: Cu(20)(-), Cu(20)(+), as well as Ag(20)(+) prefer icosahedral structures. Ag(20)(-) adopts a rearranged, distorted icosahedral structure. While Au(20)(-) is tetrahedral, Au(20)(+) cannot be described satisfyingly by a single isomer alone. Here a mixture of tetrahedral and distorted icosahedral structures is suggested. The influence of material and charge on the structural properties of the coinage metal icosamers is discussed.

The highly pyramidalized alkene, pentacyclo[4.3.0.0(2,4).0(3,8).0(5,7)]non-4-ene (9), has been generated via treatment of 4,5-diiodopentacyclo[4.3.0.0(2,4).0(3,8).0(5,7)]nonane (12) with n-butyllithium and tert-butyllithium. The title alkene has also been trapped as its Diels-Alder adduct with 1,3-diphenylisobenzofuran, 2,5-dimethylfuran, and spiro[2.4]hepta-4,6-diene. Products resulting from alkyllithium addition to the pyramidalized double bond of 9 have been isolated and fully characterized spectroscopically. The geometry, olefin strain energy, heat of hydrogenation, and relative HOMO/LUMO energies of 9 have been obtained by ab initio calculations at the MP2 and B3LYP levels using the 6-31G* basis set.

The structures of mass selected silver cluster cations Ag19 +, Ag38 +, Ag55 +, Ag59 +, Ag75 +, and Ag79 + have been probed at a temperature of 100 K by trapped ion electron diffraction. The structure assignment is carried out by comparison of the experimental scattering intensity with theoretical scattering functions of calculated candidate structures obtained by density functional theory. For the cluster sizes studied the resulting experimental data are invariably best described by structures based on the icosahedral motif, while closed packed structures can be ruled out.