The present paper is dedicated to the mechanical and fracture characterisation of a specific earthen material, that is, the shot-earth 772. Although such a material has been recently characterised from a microstructural, chemical and physical point of view, the knowledge of its mechanical and fracture properties (essential for extending its use in construction industry) is still lacking. Such characterisations are here performed both experimentally, through laboratory tests, and numerically, through a FE model. The experimental tests (i.e. flexural, compression and fracture tests) are carried out on shot-earth specimens according to Recommendations available for concrete and a method proposed by some of the present authors, named Modified Two-Parameter Model. The numerical analyses are performed by employing a micromechanical model (implemented in a non-linear 2D FE homemade code), which allows to simulate both flexural and fracture behaviour of the shot-earth examined. Finally, the obtained numerical results are compared with the experimental ones.

In this study, mulberry branch from 12 planting areas in China were collected, and the contents of 12 compositions in these mulberry branch and their differences in bioactivities were compared. The effects of climate characteristics (environmental factors) in the planting areas on the compositions and the bioactivities of mulberry branch were analyzed by partial least square regression and multiple factor analysis. We found that the precipitation and temperature difference in the planting areas were important influencing factors, which could change the content and ratio of key compositions in mulberry branch, which in turn lead to differences in bioactivities. Planting environments with smaller temperature difference will make the anti-apoptotic effect of mulberry branch more prominent, and adequate irrigation will promote anti-oxidative effect of mulberry branch. These research results provide evidence for improving mulberry planting conditions and rational use of resources from the perspective of mathematical analysis.

A document by Xinxiang Xu. Click on the document to view its contents.

Hypervirulent Klebsiella pneumoniae (hvKP) is recognized as a life-threatening community-acquired infection associated with pyogenic liver abscess. However, rhabdomyolysis secondary to hvKP infection is rare. We report the first case of rhabdomyolysis due to hvKP infection in a patient who survived. rhabdomyolysis and pyogenic liver abscess becoming septic shoc

Increasing the yield of rice has always been one of the primary purposes of rice breeding. However, panicle degeneration, a complex characteristic regulated by many genes and commonly encountered in rice production, seriously reduces yield. In this study, we obtained a new apical panicle degeneration mutant named ym48, which induces a marked degeneration rate and reduces grain yield in rice. Cellular and physiological analyses revealed that the apical panicle in ym48 undergoes programmed cell death, accompanied by the accumulation of higher levels of peroxide. Next, the OsCAX1a gene, which is responsible for Ca 2+ transportation, was identified, and a highly conserved A to G substitution was noted at the 190 th nucleotide in ym48, which seriously damaged Ca 2+ transport. Through hydroponics assays and Ca 2+ quantification, we found that Ca 2+ transportation and distribution from the underground part to apical tissues was blocked and overaccumulated in mutant stems. In general, this Ca 2+ deficiency mediated by OsCAX1a induced peroxide accumulation and resulted in programmed cell death in the apical panicle of the ym48 mutant. Our results demonstrate the essential role of OsCAX1a in Ca 2+ transportation and distribution, laying a foundation to further explore the genetic and molecular mechanisms of panicle development and differentiation in rice.

Ovine papillomavirus (OaPV) comprises four genotypes; OaPV1, OaPV2, and OaPV4 are fibropapillomaviruses within the genus Delta-papillomavirus ( Delta-PV ), whereas OaPV3 is an epitheliotropic virus that belongs to the genus Dyokappa-papillomavirus ( Dyokappa-PV ). To date, all of them have been known to infect sheep only. OaPV1, OaPV2, and OaPV4 have been associated with ovine cutaneous and mucosal fibropapillomas, while OaPV3 is a key factor in the squamous cell carcinoma (SCC) pathway of the sheep skin. Peripheral blood mononuclear cell (PBMC) samples obtained from 128 cattle at public slaughterhouses were investigated using droplet digital polymerase chain reaction (ddPCR). ddPCR is a new-generation PCR technique that enables accurate and absolute quantification of target molecules with high sensitivity and specificity. All OaPVs were detected by identification and quantification of nucleic acids using specific fluorescent probes. Of 128 PBMC samples, 100 (~78%) showed OaPV infections. Further, 42, 35, and 23 PBMC samples showed single, double, and triple OaPV infections, respectively. OaPV1 was responsible for 22 single infections, OaPV2 caused 16 single infections, and OaPV3 and OaPV4 caused two single infections each. OaPV1 and OaPV2 were the most frequent ovine viruses in dual and triple infections. In many PBMC samples, both ovine Delta-PV and Dyokappa-PV were found to be transcriptionally active, as shown by the detection and quantification of E5 oncogene transcripts for OaPV1, L1 transcripts for OaPV2, E6 and E7 transcripts for OaPV3, and E6 for OaPV4. OaPVs were found in the blood samples from cattle that shared grasslands rich in bracken ferns known to contain immunosuppressant substances. Furthermore, OaPVs were also found in cattle from intensive livestock farming without any contact with sheep. Because OaPV DNA was detected in both grass hay and corn silage, it is conceivable that these feed may be the viral sources.

Changes in species interactions due to species loss are threatening ecological networks. To explore the responses of arthropod networks to global changes, we conducted a multifactorial field experiment in temperate grassland, in which nitrogen (N) deposition, drought and snowmelt timing were manipulated. We constructed modular networks for arthropod functional groups and assessed their complexity by connectance, interaction diversity and interaction strength. Specifically, the pattern of reduction of network complexity was different in N and drought conditions: (a) increased foliar N strengthened single pathway and weakened the net effect of other pathways in N treatment; (b) filtered plant species and changed micro-habitats in drought conditions. Whereas delayed snowmelt increased arthropod abundance only in early spring, but its interaction with N treatment or drought showed various impacts on functional groups. Therefore, it is suggested that the co-effect of multiple global change factors, occurring in different seasons, should be considered as a panorama.

How first-time animal migrants find specific destinations remains an intriguing ecological question. Migratory marine species use geomagnetic map cues acquired as juveniles to aide long-distance migration, but less is known for long-distance migrants in other taxa. We test the hypothesis that naïve Eastern North American fall migratory monarch butterflies (Danaus plexippus), a species that possesses a magnetic sense, locate their overwintering sites in Central Mexico using inherited geomagnetic map cues. We examined whether overwintering locations and the abundance of monarchs changed with the natural shift of Earth’s magnetic field from 2004 to 2018. We found that migratory monarchs continued to overwinter at established sites in similar abundance despite significant shifts in the geomagnetic field, which is inconsistent with monarchs using fine scale geomagnetic map cues to find overwintering sites. It is more likely that monarchs use geomagnetic cues to assess migratory direction rather than location and use other cues to locate overwintering sites.

Determining what factors influence the distribution and abundance of wildlife populations is crucial for implementing effective conservation and management actions. Yet, for species with dynamic seasonal, sex-, and age-specific spatial ecology, like the diamondback terrapin (Malaclemys terrapin; DBT), doing so can be challenging. Moreover, environmental factors that influence the distribution and abundance of DBT in their northernmost range have not been quantitatively characterized. We investigated proximity to nesting habitat as one potential driver of spatiotemporal variation in abundance in a three-step analytical approach. First, we used a scale selection Resource Selection Function (RSF) approach based on NLCD landcover data to identify the scale at which DBT are selecting for (or avoiding) landcover types to nest. Next, we used RSF to predict areas of suitable nesting habitat and created an index of nest suitability (NSI). Finally, analyzing visual count data using a generalized linear mixed model (GLMM), we investigate spatiotemporal drivers of relative abundance, with a specific focus on whether similar factors affect offshore abundance and onshore nest site selection. We found the scale of selection for developed and saltmarsh land use classes to be 500 m and 525 m and coniferous, beach and open water land use classes to be 100 m. Selection was positive for nesting areas proximal to saltmarsh and beach habitat and negative for developed, coniferous and open water. Expected relative abundance was best explained by the interaction between NSI and day of season, where expected relative abundance was greater within high NSI areas during the nesting season (2.30 individuals, CI: 1.29 – 4.10) compared to areas of low NSI (1.99 individuals, CI: 1.27 – 3.13). Our results provide evidence that inferred spatial patterns of suitable nesting habitat explain spatiotemporal patterns of terrapin movement and abundance.

1. Omnivores utilise dietary sources which differ in nutrients, hence dietary restrictions due to environmental change or habitat alteration should cause nutrient limitations; and thus, deterioration of body condition if omnivory is obligate. 2. We investigated how the body condition of the Village weaver Ploceus cucullatus (weavers), which forages predominantly on grains, responds to insects and fruits deprivation. 3. Forty wild-caught weavers held in aviaries were fed a combination of grains and fruits, or grains and insects ad libitum for eight weeks. We confirmed diet preference by recording the number of foragers on each diet option per minute for one hour and the amount of food left-over after 3 hours of foraging. Fortnightly, we assessed indices of body condition including body mass, pectoral muscle, and fat scores, Packed Cell Volume (PCV) and Haemoglobin Concentration (HBC). We modelled the number of foragers, food left-over and body condition as functions of diet, while accounting for time (weeks) and sex effects. 4. We confirmed grains as the preferred diet and found that males ate more fruits and insects than females. Weavers fed on grains and fruits lost body and pectoral muscle mass and accumulated less fat than those fed on grains and insects. This effect was sex-dependent: females deprived of insects lost more pectoral muscle mass than males of the same group and males but not females, deprived of fruits accumulated more fat reserve than those deprived of insects. PCV and HBC did not differ between diets but increased over the eight weeks. 5. Weavers are likely obligate rather than facultative omnivores, with insects as being a more nutritive supplement than fruits. We conclude that nutrient limitation arising from environmental change or habitat alteration can impair body condition and affect physiological response to environmental seasonality in other obligate omnivores like the weavers.

Abstract: This study was conducted in Gerba Dima Forest, South Western Ethiopia to formulate allometric equations for Pouteria adolfi-friederici. Prior to collecting data for tree allometry, the study forest was stratified into 3 forest strata based on altitudinal variation. By employing semi-destructive technique, 30 individuals were systematically selected and sampled for measuring biomass along the three forest strata. Based on the data collected, several equations were developed. Before establishing the allometric equation, scatter plots were used to see whether the relationship between independent and dependent variables was linear. Furthermore, several allometric relationships between independent and dependent variables were tested. The best-fit model developed was validated by testing the regression assumptions. AGB was regressed against the various forms of predictors (i.e., DBH, H and WD) and three allometric models showed significant performance (p < 0.05) on their F-test. Among the three allometric equations which showed significant performance, the selection of the best-fit model was conducted based on their P-value, adjusted r2, AIC, RMSE. The two models are nested to the third model and hence the complete model, lnAGB=1.806+1.419×lnDBH+0.628×lnWD, is selected as the best-fit model against the other two nested models since the p-values of coefficients of the complete model are significant (p < 0.05).

Ecological theory aims to understand how and why species differences allow competitors to coexist, but explanations remain inconsistent with data. Tightly constrained parameter tradeoffs needed for coexistence in models contrast with evidence that forests can support high diversity and be invaded repeatedly by species that lack specialized tradeoffs. By translating environmental responses to individual covariance, a universal coexistence hypothesis shows i) that species differences lead to a natural tendency to concentrate competition within the species, the common feature needed to promote coexistence in models, and ii) the fingerprint of this effect is available in covariances between individuals that can be observed in nature. The many ways in which species differ make high diversity almost inevitable. This covariance not only provides the evidence for this mechanism; it further provides a new direction for earth surface models that currently cannot sustain diverse communities despite large numbers of evidence-based parameters.

In the presented study, a combined physiology, proteomics and gene expression study was performed using P. massoniana seedlings cultivated at various calcium levels. The aim of the study is to investigate the impacts of exogenous calcium on P. massoniana seedling growth and development and to reveal the underlying molecular mechanisms. The results showed that calcium deficiency lead to severe seedling growth and development inhibition while adequate exogenous calcium markedly improved the growth and development. The underlying mechanisms involved diverse calcium influenced biological processes and metabolism pathways including photosynthesis, carbohydrate metabolism and energy production, protein metabolism, secondary metabolism and calcium signal transduction and calcium ion homeostasis. In general, calcium deficiency inhibited or impaired these pathways and processes, while sufficient exogenous calcium improved and benefited these cellular events through regulating a number of related enzymes and proteins. Besides, adequate exogenous calcium supply relieved oxidation stress which occurred at low calcium level. Enhanced cell wall formation and consolidation and cell division also play a role in exogenous calcium improved P. massoniana seedling growth and development. Our study facilitates the elucidation of the potential regulatory role of calcium in P. massoniana physiology and biology and is of guiding significance in pinaceae plants forestry.

The electromagnetic scattering problem over a wide incident angle can be rapidly solved by introducing the compressive sensing theory into the method of moments, whose main computational complexity is comprised of two parts: a few calculations of matrix equations and the recovery of original induced currents. To further improve the method, a novel construction scheme of measurement matrix is proposed in this paper. With help of the measurement matrix, one can obtain a sparse sensing matrix, and consequently the computational cost for recovery can be reduced by at least half. The scheme is described in detail, the analysis of computational complexity and numerical experiments are provided to demonstrate the effectiveness.

Background : We aimed to investigate food allergen sensitization as a prognostic factor of new onset wheezing episodes as well as of wheezing severity during follow up in young children with recurrent wheezing. Our secondary aim was to compare serum levels of Club Cell-16 (CC-16) and surfactant protein D (SP-D) among wheezing children with and without food allergen sensitization as potential pathogenetic indicators of the association between food allergen sensitivity and wheezing. Methods : This was a prospective cohort study among children with recurrent wheezing; specific-IgE to five common foods allergens was assessed at baseline and children were followed-up for one year for new onset wheezing episodes. Baseline wheezing severity score, CC-16 and SP-D levels were measured. Results : We enrolled 295 children among which 44 were food specific IgE (Fx5) (+). Poisson regression analysis with food allergen sensitivity, age and wheezing score at presentation revealed that Fx5 positivity changed yearly frequency of wheeze by a factor of 1.66 (p=0.05, 95%CI: (0.99-2.75)). Age changed the yearly frequency of wheeze by a factor of 0.95 (p=0.005, 95%CI: (0.92-0.99)). One-point change in wheezing score at presentation changed the wheezing frequency in the following year by a factor of 1.11 (p=0.005, 95%CI: (0.67-1.99)). Levels of CC-16 and SP-D were not significantly different between the two groups (p=0.679 and p=0.988). Conclusion : Food allergen sensitization defined as serum specific IgE positivity irrespective of food associated clinical allergy findings is associated with worse prognosis of wheezing in children.

Introduction: Bronchopulmonary dysplasia (BPD) is characterized by lung injury with varying degrees of disrupted alveolarization, vascular remodeling, inflammatory cell proliferation, and pulmonary edema. Diuretics are often used to ameliorate the symptoms or progression of BPD. Our primary objective was to use lung ultrasound (LUS) to determine if diuretics decrease pulmonary edema in infants with BPD. The secondary objective was to assess changes in respiratory support during the first week after initiation of diuretics. Methods: Premature infants requiring non-invasive respiratory support and starting diuretic therapy for evolving BPD were compared with a similar group of infants not receiving diuretics (control). For the diuretic group, LUS exams were performed before and on days 1, 3 and 6 after initiation of treatment. For the control group, LUS was performed at equivalent time points. A composite pulmonary edema severity (PES) score of 0 to 5 was calculated based on the total number of B-lines in 6 scanned areas. Respiratory support parameters (FiO2, nasal cannula flow or CPAP) were also recorded. Results: Infants in the diuretic (n=28) and control (n=23) groups were recruited at median corrected gestational ages of 34.2 (33.3-35.9) and 34.0 (33.4-36.3) weeks, respectively ( p=0.82). PES scores, FiO2, and respiratory flow support decreased significantly from day 0 to 6 ( p<.0001, p=0.001, and p=0.01, respectively) in the diuretic group, but not in the control group. Conclusion: Diuretic use is associated with decreased pulmonary edema and improved oxygenation in infants with BPD during the first week of treatment.

Cytomegalovirus (CMV) is the most common congenital and perinatal viral infection. It can occur in utero, during delivery, by blood transfusion or by breast milk. These are usually asymptomatic in term infants due to the presence of maternally derived, trans placental CMV (Ig)G antibodies, but in premature neonates, can lead to severe disease because of lack of sufficient quantities of these antibodies 1. In lactating CMV seropositive mothers, transmission occurs in 22.8% premature infants, with symptomatic disease in 34.5%. 2 We report 3 cases of neonates with atypical CMV infection involving lungs and requiring treatment with antivirals.

Background. Anaphylaxis is a severe and potentially life-threatening allergic reaction which has a detrimental impact on quality of life (QoL), however little is known about the impact of anaphylaxis, across the various causes, on adults. The aim of this study was to assess the impact of anaphylaxis on QoL and mental health in adults. Methods. Participants (n=142; 60% female) were recruited from a regional allergy centre (Birmingham, U.K) following systematic specialist evaluation. They completed measures of generic QoL (WHOQoL BREF), anaphylaxis specific QoL (A-QoL-Adults), anxiety and depression (HADS) and stress (PSS). Results. Anaphylaxis triggers were mainly to medication or during general anaesthesia (29.6%), food (29.6%), wasp or bee venom (16.2%), or were spontaneous (21.1%). Adults with anaphylaxis had significantly poorer general QoL and stress than published data from a healthy population. Females had significantly poorer anxiety and depression than norm data (all p<0.01). Poorer anaphylaxis specific QoL was significantly related to greater stress, depression, anxiety, poorer general QoL and demographic and clinical variables such as age, gender, severity of anaphylaxis, presence of other atopic conditions (all p<0.05). Regression analysis showed that anxiety, depression and number of anaphylactic reactions were significant predictors for anaphylaxis specific QoL. Conclusions. Anaphylaxis has an adverse impact on QoL and mental health of adults across different triggers. Anxiety, depression and number of reactions in particular seem to be important in explaining the impact on QoL and should be of particular note for clinicians managing adults with this condition, and when considering specialist psychological support.

Background Cystic Fibrosis (CF) and autism spectrum disorder (ASD) are life-long conditions with intense treatment burdens for patients and families. Patients with a concurrent diagnosis (CF-ASD) experience unique challenges to CF care. This study describes the experiences of our multidisciplinary CF team in caring for patients with CF-ASD and provides insight into provider and parental perspectives on clinical management. Methods This is a three-part IRB-approved study involving 1) retrospective chart review of patients with CF-ASD, 2) qualitative interviews with multi-disciplinary care teams, and 3) qualitative interviews with caregivers of patients with CF-ASD. Challenges in clinical management of this specific cohort were compiled using data from chart review and care team interviews. Strategies to address these challenges were identified and rated by individual families based on relevance and practicality. Results Within our CF center, 12 patients have an official diagnosis of ASD. Median age of patients with CF-ASD was 8.5 years (range 3-20 years), 75% were male, and 83% were on highly effective modulator therapy. Clinical challenges included sensory processing issues, environmental overstimulation, intolerance to procedures and disrupted routines. Potentially impactful strategies include patient-specific coping plans, guided behavioral interventions, parental advocacy, and improved communication between the family and multidisciplinary team. Conclusions Children with CF-ASD face extraordinary challenges beyond the experience of neurotypical children with CF. Increased awareness of this complex dual diagnosis will help providers be sensitive to the unique needs of these patients, to help build consistent and trustworthy relationships with families, and to provide effective clinical care despite limitations.

Abstract Objective: To investigate serum human epididymis-4 (HE4) as a predictive biomarker of intrauterine progestin response in endometrial cancer and atypical endometrial hyperplasia (AEH). Design: Prospective observational study. Setting: Consecutive sample of women attending a tertiary gynaecological oncology centre in the North West of England. Population: Women with AEH or early stage, low grade endometrial cancer who were unfit or declined primary surgical management; 48 in the discovery cohort and 28 in the validation cohort. Methods: Women were treated with a levonorgestrel intrauterine system (LNG-IUS) for 12 months. Endometrial biopsies and imaging were performed to assess treatment response. Pre-treatment serum HE4 was analysed by chemiluminescence immunoassay and diagnostic accuracy and logistic regression analyses performed. Main outcome measure: Progestin response at 12 months defined by histology and imaging. Results: Baseline serum HE4 was significantly higher in non-responders than responders in both discovery [134.6pmol/L (IQR:94.0-292.4) vs 76.5pmol/L (IQR:59.7-87.3), p<0.001] and validation cohorts [108.2pmol/L (IQR:80.3-119.2) vs 64.4pmol/L (IQR:53.0-73.0), p=0.004]. An HE4≥77pmol/L had a sensitivity and specificity for progestin treatment response of 83.3% and 53.3% in the discovery cohort, and 85.7% and 76.2% and in the validation cohort, respectively. When expressed as a continuous variable, the AUC was 0.81 (95%CI:0.67-0.95) and 0.87 (95%CI:0.73-1.00) for the discovery and validation cohorts, with every 1pmol/L of HE4 increasing the likelihood of progestin treatment failure by 2% and 5%, after adjustment for age and histology, respectively (p=0.02 and p=0.18). Conclusion: Serum HE4 shows promise as a predictive biomarker of progestin treatment response in endometrial cancer and AEH.

Study Objective: Development of a prediction tool for histopathological adenomyosis diagnosis after hysterectomy based on MRI and clinical parameters. Design: Single-centre retrospective cohort study Setting: Gynaecological department of a referral hospital from 2007-2022. Population: 296 women undergoing hysterectomy with preoperative pelvic MRI Methods: MRI’s were retrospectively assessed for adenomyosis markers (junctional zone (JZ) parameters, high signal intensity foci (HSI) foci) in a blinded fashion. A multivariate regression model for histopathological adenomyosis diagnosis was developed based on MRI and clinical variables from univariate analysis with p>0.10 and factors deemed clinically relevant. Results: 131/296 women (44.3%) had histopathological adenomyosis. Patients were of comparable age at hysterectomy, BMI and clinical symptoms, p>0.05. Adenomyosis patients more often had undergone a curettage (22.1% vs. 8.9%, p=0.002), a higher mean JZ thickness (9.40 vs. 8.35mm, p <.001), maximal JZ thickness (16.00 vs. 13.40mm, p<.001), mean JZ/myometrium ratio (0.56 vs. 0.49, p=.040), and JZ differential (8.60 vs. 8.15mm, p=.003). Presence of HSI foci was a strong predictor for adenomyosis (39.7% vs. 8.9%, p<.001). Based on the parameters age and BMI, history of curettage, dysmenorrhoea, abnormal uterine bleeding (AUB), mean JZ, JZ Differential  5mm, JZ/myometrium ratio >.40, and presence of HSI Foci, a predictive model was created with a good Area Under the Curve (AUC) of .776. Conclusions: This is the first study to create a diagnostic tool based on MRI and clinical parameters for adenomyosis diagnosis. After sufficient external validation, this model could function as a useful clinical-decision making tool in women with suspected adenomyosis.

Rationale: Cystic Fibrosis (CF) newborn screening (NBS) algorithms in the USA vary by state. Differences in CF NBS algorithms could potentially affect the detection rate of CF newborns and lead to disparities in CF diagnosis amongst different racial and ethnic groups. Objectives: Generate a database of CF NBS algorithms in the USA and identify processes that may potentially lead to missed diagnoses or lead to health care disparities. Methods: We sent an online survey to state and regional CF and NBS leaders about the type and threshold of immunoreactive trypsinogen (IRT) cutoff used and methods used for CFTR gene variant analysis. Follow-up by email and phone was done to ensure a response from every state, clarify responses, and resolve discordances . Results: There was wide variation in the NBS algorithms employed by different states. Approximately half the states use a floating IRT cutoff and half use a fixed IRT cutoff. CFTR variant analysis also varied widely, with 2 states analyzing only for the F508del variant and 4 states incorporating CFTR gene sequencing. The other states used CFTR variant panels ranging from 23 to 365 CFTR variants. Conclusions: CF NBS algorithms vary widely amongst the different states in the USA, which affects the ability of CF NBS to diagnose newborn infants with CF consistently and uniformly across the country and potentially may miss more infants with CF from minority populations. Our results identify an important area for quality improvement in CF NBS.

Although COP is idiopathic by definition, it is important to investigate each diagnosed case for potential causes, such as iatrogenic from radiation or known causative medications [1], connective tissue diseases, inflammatory bowel disease, malignancies, history of lung transplant or bone marrow graft. OP may present weeks to months before other signs of connective tissue disorders and therefore the patient should undergo serologic testing for these diseases. [6] In the case presented, the specific etiology was unyielding and so remains cryptogenic in nature. This patient’s symptoms quickly improved following the use of steroids and tolerated tapering off completely without relapse one year out from initial diagnosis.

Objective: To assess the impact of an oocyte retrieval simulation training program (ORSTP) on the clinical performance of residents. Design: Prospective comparative study. Setting: A tertiary care center. Population: All OR performed by residents between May 2017 and November 2020. Methods & main outcome measures: The Simulation (S) group included OR performed by residents who had undergone an ORSTP before performing them on patients (n=422) and the control (C) group included OR performed by residents who had not received prior simulation training (n= 329). Our main outcome measure was the OR rate (ORR) (number of oocytes collected/number of follicles aspirated) during the first 3 months of the rotation. Results: In the S group, 6 residents aspirated 657 ovaries while in the C group, 5 residents aspirated 508 ovaries. The mean ORR during the first 3 months of rotation were comparable between the S and C groups (59% vs 58%). ORR during the first and second month, and at the end of the rotation were also comparable between the S and C groups (54% vs 63%, 58% vs 59% et 58% vs 58%, respectively). There was no significant difference in the rate of failed OR (3.3% vs 1.8%) between the S and C groups. Finally, 16% of residents in the S group reported being stressed before their first OR compared to 40% in the C group. Conclusions: The ORSTP does not improve the residents’ clinical performance, but it could decrease their stress in clinical practice.