Recent progress and future prospects of hyperon nucleon scattering experiment

A new hyperon-proton scattering experiment, dubbed J-PARC E40, was performed to measure differential cross sections of the Σ+p, Σ−p elastic scatterings and the Σ−p → Λn scattering by identifying a lot of Σ particles in the momentum ranging from 0.4 to 0.8 GeV/c produced by the π±p → K+Σ± reactions. We successfully measured the differential cross sections of these three channels with a drastically improved accuracy with a fine angular step. These new data will become important experimental constraints to improve the theories of the two-body baryon-baryon interactions. Following this success, we proposed a new experiment to measure the differential cross sections and spin observables by using a highly polarized Λ beam for providing quantitative information on the ΛN interaction. The results of three Σp channels and future prospects of the Λp scattering experiment are described.

Optimal timing for measuring cerebral blood flow after acetazolamide administration to detect preexisting cerebral hemodynamics and metabolism in patients with bilateral major cerebral artery steno-occlusive diseases: 15O positron emission tomography studies

The present study determined the optimal timing of scanning for measurement of cerebral blood flow (CBF) after acetazolamide (ACZ) administration for detection of preexisting cerebral hemodynamics and metabolism in bilateral major cerebral artery steno-occlusive diseases. Thirty three patients underwent ¹⁵O gas positron emission tomography (PET) and each parameter was obtained in the bilateral middle cerebral artery (MCA) territories. CBF was also obtained using H₂ ¹⁵O PET scanning performed at baseline and at 5, 15, and 30 min after ACZ administration. Relative CBF at each time point after ACZ administration to baseline CBF was calculated. For MCA territories with normal cerebral blood volume (CBV) and cerebral metabolic rate of oxygen (CMRO₂), CBF continued increasing until 15 min after ACZ administration. For MCA territories with abnormally increased CBV, CBF decreased 5 min after ACZ administration. After that, CBF continued increasing until 30 min after ACZ administration. For MCA territories with abnormally decreased CMRO₂, CBF did not change 5 min after ACZ administration. Ten min later, CBF increased. The accuracy to detect abnormally increased CBV was significantly greater for relative CBF₅ than for relative CBF₁₅. The accuracy to detect abnormally decreased CMRO₂ was significantly greater for relative CBF₅ or CBF₁₅ than for relative CBF₃₀. For detecting abnormally increased oxygen extraction fraction, the accuracy did not differ among each relative CBF. These findings suggested that CBF measurement at 5 min after ACZ administration is the optimal timing for detection of preexisting cerebral hemodynamics and metabolism in bilateral major cerebral artery steno-occlusive diseases.

Early and chronic phased local coagulative responses following bioresorbable-polymer drug-eluting stent implantation

Background

Neointimal maturation after bioresorbable-polymer (BP) drug-eluting stent (DES) implantation will not be complete in the absorption phase of the polymer. We have previously reported local persistent hypercoagulation after sirolimus-eluting stent (SES) implantation by measuring local plasma prothrombin fragment 1+2 (F1+2) levels. The aim of this study is to examine time-dependent local coagulative response after BP-DES implantation.

Methods

Sixty-four patients who were treated about ten months earlier with coronary angioplasty, with no evidence of restenosis, were studied [durable-polymer (DP)-DES {SES; Cypher®: 26pts and everolimus-eluting stent (EES); Xience®: 16pts} and BP-DES (BP-EES; Synergy®: 10pts and BP-SES; Ultimaster®: 12pts)]. We measured plasma levels of F1+2 sampled in coronary sinus (CS) and sinus of Valsalva (V) at the early (2±1 months) and chronic (10±2 months) phases. The transcardiac gradient (Δ) was defined as CS level minus V level.

Results

No significant differences were observed in the percent diameter stenosis between the DP- and BP- DES groups (11.5±15.5 vs 14.1±11.9%). The ΔF1+2 was significantly lower in the BP-DES group than in the DP-DES group at the chronic phase (7.5±16.1 vs 16.4±17.1pmol/l, p<0.05). In the BP-DES group, the ΔF1+2 did not differ significantly between the early and chronic phases (7.0±14.1 vs 7.5±16.1pmol/l, NS).

Conclusion

Lower local coagulative response was observed at the chronic phase after BP-DES implantation compared to DP-DES implantation, and local hypercoagulation after BP-DES implantation was not observed at the early phase compared to the chronic phase. These findings might lead to the possibility of shorter dual antiplatelet therapy after BP-DES implantation.

Funding Acknowledgement

Type of funding sources: None.

Five-Year Outcomes of Medical Management Alone for Adult Patients with Ischemic Moyamoya Disease without Cerebral Misery Perfusion

INTRODUCTION

No clear guidelines for treating adult patients with ischemic moyamoya disease (MMD) without cerebral hemodynamic compromise such as misery perfusion have been established. Our previous prospective cohort study of adult patients with MMD without misery perfusion who were treated with medical management alone, including an antiplatelet drug, showed a recurrent ischemic event rate of 3% per 2 years. The present prospective study aimed to elucidate the 5-year clinical, cerebral perfusion, and cognitive outcomes of medical management alone for Japanese adult patients with ischemic MMD without cerebral misery perfusion by following the same patients for another 3 years.

METHODS

In total, 68 patients without recurrent events at a 2-year follow-up were prospectively followed up for another 3 years. Cerebral blood flow (CBF) in the symptomatic cerebral hemisphere was measured using brain perfusion single-photon emission computed tomography at inclusion and at the end of the subsequent 3-year follow-up. Neuropsychological testing was performed at inclusion and at the end of the initial 2- and subsequent 3-year follow-ups.

RESULTS

During the subsequent 3-year follow-up, 2 patients (3%) developed further ischemic events. In patients without further ischemic events, CBF was significantly greater at the end of the subsequent 3-year follow-up than at inclusion (p = 0.0037), and all neuropsychological test scores improved or remained unchanged at the end of initial 2- and subsequent 3-year follow-ups compared with that at inclusion.

CONCLUSION

In adult patients receiving medical management alone for ischemic MMD without cerebral misery perfusion, the incidence of further ischemic events was 6% per 5 years and did not change between the initial 2 years after the last is-chemic event and the subsequent 3 years. In patients without further ischemic events, CBF and cognitive function had not deteriorated at 5 years after the last ischemic event.

P–632 Examination of temporal changes in phenotype and gut microbiome during the process of growth in polycystic ovary syndrome (PCOS) model induced by prenatal androgen exposure

Study question

From when do abnormality in gut microbiome and phenotypes of PCOS appear during the process of growth?

Summary answer

Reproductive phenotypes of PCOS appear from 6 weeks and metabolic phenotypes from 12 weeks onward. Alteration in gut microbiome appears as early as 4 weeks.

What is known already

The etiology of PCOS remains largely unknown, however PCOS is considered as a complex multigenic disorder with strong epigenetic and environmental influence. Previous studies have suggested that fetal over-exposure to androgens could be the main factor of the development of PCOS after birth. On the other hands, recent studies on both human and PCOS rodent models have demonstrated the association between PCOS and alteration of gut microbiome in adulthood. Furthermore, it was recently reported that gut microbiome in obese adolescent with PCOS is different from obese adolescent without PCOS.

Study design, size, duration

A rodent PCOS model induced by prenatal dehydroepiandrosterone (DHT) exposure was applied to this study. Phenotypes and gut microbiome were compared between PCOS model mice (n = 12/group) and control mice (n = 10/group) at each stage of growth; 4 weeks (prepuberty), 6 weeks (puberty), 8 weeks (adolescent), 12 weeks (young adult), and 16 weeks (adult). The determinants for PCOS phenotypes are onset of puberty, estrous cycle, morphology of ovaries, serum testosterone level, body weight, and insulin resistance.

Participants/materials, setting, methods

Pregnant dams were subcutaneously injected on days of 16, 17, and 18 of gestation with either sesame oil for control groups or sesame oil containing 250µg of DHT for prenatal DHT groups. The evaluation of PCOS phenotypes and gut microbiome in female offspring were performed at each stage of growth. For examination of gut microbiota, next generation sequencing and bioinformatics analysis of 16S rRNA genes were performed on DNA extracted from mouse fecal samples.

Main results and the role of chance

Prenatal DHT mice exhibited delayed puberty onset, disrupted estrous cycle, and significantly increased testosterone levels from 6 weeks onward. Significantly increased atretic antral follicles were observed in prenatal DHT mice at 6, 12, and 16 weeks. Prenatal DHT mice showed significantly decreased body weight at 4, 6, 8 weeks and increased body weight from 12 weeks onward. As for gut microbiome, alpha-diversity was significantly different between control and prenatal DHT mice from 8 weeks onward and beta-diversity was significantly different at 6 and 8 weeks. Altered composition of gut microbiota was observed as early as 4 weeks. At phylum level, Firmicutes are significantly increased in prenatal DHT mice at 4 and 8 weeks and decreased at 16 weeks. Actinobacteria phylum showed significant decrease at 6 and 8 weeks in prenatal DHT mice. At genus level, relative abundance of several bacterial taxa significantly differed between control and prenatal DHT mice; some taxa, such as Allobaculum, Adlercreutzia, Bilophila, Clostridium, Gemella, Gemmiger, Roseburia, Ruminococcus, Staphylococcus, and Sutterella, exhibited constant increase or decrease in prenatal DHT mice during the process of growth. Interestingly, Roseburia was never detected in prenatal DHT mice, while approximately half of control mice harbored Roseburia at 12 and 16 weeks.

Limitations, reasons for caution

It is not clearly determined whether alteration in gut microbiome is cause or result of PCOS development, although the changes in gut microbiome seemed to precede the appearance of typical PCOS phenotypes in the present study. Mouse model does not completely recapitulate human PCOS.

Wider implications of the findings: Our findings suggest that prenatal androgen exposure causes alteration of gut microbiome from pre-puberty onward, even before PCOS phenotypes become apparent. Intervention for girls at risk of PCOS with pre/pro-biotics may prevent them from developing PCOS in future.

Trial registration number

Not applicable

P–651 Strict embryo-endometrial synchrony does not contribute to the successful pregnancy during vitrified-warmed embryo transfer with hormone replacement cycles

Study question

Does strict embryo-endometrium synchronization relate to pregnancy during vitrified-warmed embryo transfer (ET) with hormone replacement (HRT) cycles?

Summary answer

A 12-hour delay in the embryo-endometrial synchrony was acceptable, and this delay was not an independent predictor of pregnancy during vitrified-warmed ET with HRT cycles.

What is known already

Embryo-endometrium synchrony is considered to be necessary for successful pregnancy in both fresh and frozen-thawed cycles. Until now, the date of ET has been determined by the synchronization of the embryo developmental stage and the endometrium on a daily basis. To date, with the advent of the time-lapse incubator, it is possible to observe the embryo development from fertilization over time and to calculate the exact time from fertilization of the transferred embryo. However, there are very few studies on the extent to which increases the accuracy of synchronization between embryo and endometrium contributes to a successful pregnancy.

Study design, size, duration

This retrospective cohort study included 319 consecutive cycles during vitrified-warmed ET with HRT between August 2016 and August 2018. This study was conducted in an academically affiliated private practice.

Participants/materials, setting, methods

We analyzed 319 vitrified-warmed single-blastocyst transfer cycles. All frozen expanded blastocysts were inseminated by intracytoplasmic sperm injection (ICSI) and cultured in a time-lapse incubator. We calculated time for the in vitro culture of the embryo after ICSI (t1) and time for progesterone-priming (t2) up to ET. The difference between t1 and t2 (delta-t) was used as an indicator of embryo-endometrium synchrony. We examined the relationship between delta-t and treatment outcomes using multivariate logistic analysis.

Main results and the role of chance

The mean patient’s age at oocyte retrieval was 35.7 (SD 4.3). The number of pregnant cycles was 157 in all treatment cycles (pregnancy rate, 49.2%). The mean value of delta-t was 9.9 h (SD 2.6) in all cycles. There was no significant difference of delta-t in pregnant (mean, SD: 10.0 h, 2.8 h) and non-pregnant cycles (mean, SD: 10.0 h, 2.3 h). Treatment cycles were classified according to the quartile of delta-t, and we examined the percentages of pregnant cycles in each group. There were no significant differences in pregnancy rates among the groups (p = 0.75). On multivariate logistic analysis, patient’s age (adjusted odds ratio [aOR]: 0.94, 95% confidence interval [CI]: 0.89–0.99), previous treatment cycles (aOR: 0.74, 95% CI: 0.56–0.99), endometrial thickness at ET (aOR: 1.19, 1.04–1.36), and good quality blastocysts (>3BB according to Gardner’s classification) at vitrification (aOR: 2.49, 95% CI: 1.23–5.05) were independent predictive factors for pregnancy. On the other hand, delta-t did not contribute to pregnancy (aOR: 1.00, 95% CI: 0.99–1.00).

Limitations, reasons for caution

We did not examine the effects of embryo-endometrium synchrony during vitrified-warmed ET in a natural cycle. Therefore, careful interpretation of the significance of embryo-endometrium synchrony during the vitrified-warmed ET should be taken.

Wider implications of the findings: We showed the embryo-endometrium synchrony did not contribute to the pregnancy during vitrified-warmed ET with HRT cycles. These results cast doubt on the existence of an optimal implantation window by changing the timing of ET with the results of gene expression testing of the endometrium.

Trial registration number

Not applicable

Deexcitation Dynamics of Muonic Atoms Revealed by High-Precision Spectroscopy of Electronic K X Rays

We observed electronic K x rays emitted from muonic iron atoms using superconducting transition-edge sensor microcalorimeters. The energy resolution of 5.2 eV in FWHM allowed us to observe the asymmetric broad profile of the electronic characteristic Kα and Kβ x rays together with the hypersatellite K^{h}α x rays around 6 keV. This signature reflects the time-dependent screening of the nuclear charge by the negative muon and the L-shell electrons, accompanied by electron side feeding. Assisted by a simulation, these data clearly reveal the electronic K- and L-shell hole production and their temporal evolution on the 10-20 fs scale during the muon cascade process.

Nutritional value of suckler beef from temperate pasture systems

The role of beef in human diets has been questioned over the last few decades, due largely to its typically high mass-based carbon footprint. However, recent advancements in sustainability literature challenge this paradigm based on the new theory that climate impacts of food commodities should be measured relative to their overall nutritional value rather than their nominal mass. This shift has opened a new opportunity for the global beef industry, and especially for pasture-based systems that can avoid food-feed competition for land and other resources, as beef is a nutritionally dense food. Nonetheless, the sector's true capability to supply a wide range of nutrients for humans, consistently across multiple systems under multiple weather patterns, has not been well-documented. Using whole-system datasets from the North Wyke Farm Platform in the South West of England, we investigated the nutritional value of beef produced from the three most common pasture systems in temperate regions: permanent pasture (PP), grass and white clover (GWC) and a short-term monoculture grass ley (MG). Beef produced from these three pasture systems was analysed for key nutrients (fatty acids, minerals and vitamin E) over three production cycles (2015-2017) to determine potential differences between systems. Fatty acid, mineral and vitamin E profiles of the pasture and silage fed to each group were also assessed, with subtle differences between pastures reported. For beef, subtle differences were also observed between systems, with GWC having higher omega-6 polyunsaturated fatty acid (PUFA) concentrations than PP and MG. However, the overall nutritional quality of beef was found to be largely comparable across all systems, suggesting that temperate pasture-based beef can be classified as a single commodity in future sustainability assessments, regardless of specific sward types. A 100 g serving of temperate pasture-based beef was found to be a high source (>20% recommended daily intake: RDI) of protein, monounsaturated fatty acids, saturated fatty acids, vitamins - B2, B3, B12 and minerals - Fe, P, Zn; a good source (10-19% RDI) of vitamin - B6 and mineral - K; and a complementary source (5-9% RDI) of omega-3 PUFA, vitamin - B9 and minerals - Cu, Mg, Se. The nutritional value of a food item should be used in defining its environmental cost (e.g. carbon footprint) to make fair comparisons across different food groups (e.g. protein sources). Here, we showed that pasture-based beef had a nutrient indexed carbon footprint of between 0.19 and 0.23 Kg CO2-eq/1% RDI of key nutrients.

Revealing x-ray and gamma ray temporal and spectral similarities in the GRB 190829A afterglow

Gamma-ray bursts (GRBs), which are bright flashes of gamma rays from extragalactic sources followed by fading afterglow emission, are associated with stellar core collapse events. We report the detection of very-high-energy (VHE) gamma rays from the afterglow of GRB 190829A, between 4 and 56 hours after the trigger, using the High Energy Stereoscopic System (H.E.S.S.). The low luminosity and redshift of GRB 190829A reduce both internal and external absorption, allowing determination of its intrinsic energy spectrum. Between energies of 0.18 and 3.3 tera-electron volts, this spectrum is described by a power law with photon index of 2.07 ± 0.09, similar to the x-ray spectrum. The x-ray and VHE gamma-ray light curves also show similar decay profiles. These similar characteristics in the x-ray and gamma-ray bands challenge GRB afterglow emission scenarios.

Immunohistochemical expression levels of cyclin D1 and CREPT reflect the course and prognosis in oral precancerous lesions and squamous cell carcinoma

Cyclin D1 is the most essential progressive regulator of the cell cycle, and its transcription is enhanced by CREPT (cell cycle-related and expression-elevated protein in tumour). These molecules regulate cell growth, and their aberrant expression can cause malignant transformation. In this study, the expression of these molecules was explored to investigate the molecular alterations in oral precancerous lesions and squamous cell carcinoma. Cyclin D1 and CREPT expression was examined immunohistochemically in tissue specimens from 55 patients with oral epithelial precursor lesions (OEPLs) and 84 patients with oral squamous cell carcinoma (OSCC). Associations between the results and clinicopathological variables were examined. Cyclin D1 and CREPT expression levels were higher in OSCC than in OEPLs. Furthermore, there were statistically significant differences in cyclin D1 expression among the different grades of OEPLs and OSCC lesions. In OSCC, there were statistically significant differences in CREPT expression according to sex, T stage, and degree of differentiation. In addition, the expression of both molecules was significantly correlated with postoperative metastasis and modes of invasion. The expression of cyclin D1 and CREPT was found to depend upon the state of development and progression of the oral epithelial lesions, and clinicopathological behaviours might be affected by these molecules in OSCC.

Data to identify key drivers of animal growth and carcass quality for temperate lowland sheep production systems

With the growing demand for animal-sourced foods and a serious concern over climate impacts associated with livestock farming, the sheep industry worldwide faces the formidable challenge of increasing the overall product supply while improving its resource use efficiency. As an evidence base for research to identify key drivers behind animal growth and carcass quality, longitudinal matched data of 741 ewes and 2978 lambs were collected at the North Wyke Farm Platform, a farm-scale grazing trial in Devon, UK, between 2011 and 2019. A subset of these data was subsequently analysed in a study to assess the feasibility of using a lamb's early-life liveweight as a predictor of carcass quality [1]. The data also have the potential to offer insight into key performance indicators (KPIs) for the sheep industry, or what variables farmers should measure and target to increase profitability.

Multicenter prospective trial of total gastrectomy versus proximal gastrectomy for upper third cT1 gastric cancer

BACKGROUND

The appropriate surgical procedure for patients with upper third early gastric cancer is controversial. We compared total gastrectomy (TG) with proximal gastrectomy (PG) in this patient population.

METHODS

A multicenter, non-randomized trial was conducted, with patients treated with PG or TG. We compared short- and long-term outcomes between these procedures.

RESULTS

Between 2009 and 2014, we enrolled 254 patients from 22 institutions; data from 252 were included in the analysis. These 252 patients were assigned to either the PG (n = 159) or TG (n = 93) group. Percentage of body weight loss (%BWL) at 1 year after surgery, i.e., the primary endpoint, in the PG group was significantly less than that of the TG group (- 12.8% versus - 16.9%; p = 0.0001). For short-term outcomes, operation time was significantly shorter for PG than TG (252 min versus 303 min; p < 0.0001), but there were no group-dependent differences in blood loss and postoperative complications. For long-term outcomes, incidence of reflux esophagitis in the PG group was significantly higher than that of the TG group (14.5% versus 5.4%; p = 0.02), while there were no differences in the incidence of anastomotic stenosis between the two (5.7% versus 5.4%; p = 0.92). Overall patient survival rates were similar between the two groups (3-year survival rates: 96% versus 92% in the PG and TG groups, respectively; p = 0.49).

CONCLUSIONS

Patients who underwent PG were better able to control weight loss without worsening the prognosis, relative to those in the TG group. Optimization of a reconstruction method to reduce reflux in PG patients will be important.

Observation of Coulomb-Assisted Nuclear Bound State of Ξ^{-}-^{14}N System

In an emulsion-counter hybrid experiment performed at J-PARC, a Ξ^{-} absorption event was observed which decayed into twin single-Λ hypernuclei. Kinematic calculations enabled a unique identification of the reaction process as Ξ^{-}+^{14}N→_{Λ}^{10}Be+_{Λ}^{5}He. For the binding energy of the Ξ^{-} hyperon in the Ξ^{-}-^{14}N system a value of 1.27±0.21  MeV was deduced. The energy level of Ξ^{-} is likely a nuclear 1p state which indicates a weak ΞN-ΛΛ coupling.

Changes in muscle activity with exercise-induced fatigue in Thoroughbred horses

Understanding the effects of fatigue can provide guidance for training regimens and injury prevention. We have previously reported that the integrated-electromyogram (iEMG) values of the M. gluteus medius and brachiocephalicus decreased with exercise-induced fatigue, whereas those of the M. longissimus dorsi and infraspinatus were not affected. We hypothesised that exercise-induced fatigue would decrease the activities of the muscles associated with propulsive force but not associated with joint stabilisation. Surface EMG recordings of the forelimb muscles (M. triceps brachii, common digital extensor, ulnaris lateralis), and hindlimb muscles (M. semitendinosus, extensor digitorum longus, extensor digitorum lateralis and flexor digitorum lateralis) were conducted on eight Thoroughbreds. Horses galloped on a treadmill (grade, 3%) at a constant speed (12.6-14.8 m/s) until they could not maintain their position with minimal human encouragement (~5 min). The stride frequency, iEMG for a stride and median frequency during muscle discharge were calculated every 30 s. These parameters were compared between the start and end of the test phase for the leading and trailing limbs. The stride frequency (P<0.01) and iEMG values of the M. semitendinosus in both the leading (P<0.01) and trailing limbs (P<0.05) and those of the M. extensor digitorum longus in the trailing limbs (P<0.05) significantly decreased at the end of the test. No median frequency changes were observed in the assessed muscles. Although muscular fatigue itself was not detected, observed fatigue caused by high-intensity exercise resulted in inability to maintain speed, which was associated with decreased iEMG values in the hip extensor muscles that generate propulsive force. In contrast, almost all muscles that stabilise joints were unaffected by fatigue. One exception was the decreased muscle activity observed in the M. extensor digitorum longus of the trailing limb, which may suggest unstable ground contact. Muscle activity changes with fatigue might be associated with muscle functions.

Development of cerebral microbleeds in patients with cerebral hyperperfusion following carotid endarterectomy and its relation to postoperative cognitive decline

OBJECTIVE

A primary cause of cognitive decline after carotid endarterectomy (CEA) is cerebral injury due to cerebral hyperperfusion. However, the mechanisms of how cerebral hyperperfusion induces cerebral cortex and white matter injury are not known. The presence of cerebral microbleeds (CMBs) on susceptibility-weighted imaging (SWI) is independently associated with a decline in global cognitive function. The purpose of this prospective observational study was to determine whether cerebral hyperperfusion following CEA leads to the development of CMBs and if postoperative cognitive decline is related to these developed CMBs.

METHODS

During the 27-month study period, patients who underwent CEA for ipsilateral internal carotid artery stenosis (≥ 70%) also underwent SWI and neuropsychological testing before and 2 months after surgery, as well as quantitative brain perfusion SPECT prior to and immediately after surgery.

RESULTS

According to quantitative brain perfusion SPECT and SWI before and after surgery, 12 (16%) and 7 (9%) of 75 patients exhibited postoperative cerebral hyperperfusion and increased CMBs in the cerebral hemisphere ipsilateral to surgery, respectively. Cerebral hyperperfusion was associated with an increase in CMBs after surgery (logistic regression analysis, 95% CI 5.08-31.25, p < 0.0001). According to neuropsychological assessments before and after surgery, 10 patients (13%) showed postoperative cognitive decline. Increased CMBs were associated with cognitive decline after surgery (logistic regression analysis, 95% CI 6.80-66.67, p < 0.0001). Among the patients with cerebral hyperperfusion after surgery, the incidence of postoperative cognitive decline was higher in those with increased CMBs (100%) than in those without (20%; p = 0.0101).

CONCLUSIONS

Cerebral hyperperfusion following CEA leads to the development of CMBs, and postoperative cognitive decline is related to these developed CMBs.

Using a lamb's early-life liveweight as a predictor of carcass quality

The commercial value of lamb carcasses is primarily determined by their weight and quality, with the latter commonly quantified according to muscle coverage and fat depth. The ability to predict these quality scores early in the season could be of substantial value to sheep producers, as this would enable tailored flock management strategies for different groups of animals. Existing methods of carcass quality prediction, however, require either expensive equipment or information immediately before slaughter, leaving them unsuitable as a decision support tool for small to medium-scale enterprises. Using seven-year high-resolution data from the North Wyke Farm Platform, a system-scale grazing trial in Devon, UK, this paper investigates the feasibility of using a lamb's early-life liveweight to predict the carcass quality realised when the animal reaches the target weight. The results of multinomial regression models showed that lambs which were heavier at weaning, at 13 weeks of age, were significantly more likely to have leaner and more muscular carcasses. An economic analysis confirmed that these animals produced significantly more valuable carcasses at slaughter, even after accounting for seasonal variation in lamb price that often favours early finishers. As the majority of heavier-weaned lambs leave the flock before lighter-weaned lambs, an increase in the average weaning weight could also lead to greater pasture availability for ewes in the latter stage of the current season, and thus an enhanced ewe condition and fertility for the next season. All information combined, therefore, a stronger focus on ewes' nutrition before and during lactation was identified as a key to increase system-wide profitability.

Impact of body mass index on the clinical outcomes in heart failure patients undergoing cardiac rehabilitation

Background

Increased body mass index (BMI) has recently shown to have a favorable effect on the prognosis in heart failure (HF) patients. However, the impact of BMI on clinical events and mortality in HF patients who underwent cardiac rehabilitation (CR) remains unclear.

Purpose

This study aimed to investigate whether the obesity paradox is present in HF patients who have undergone CR.

Methods

This study enrolled 238 consecutive HF patients who had undergone CR at our university hospital between November 2015 and October 2017. The clinical characteristics and anthropometric data of these patients, including BMI, were collected at the beginning of the CR. The major adverse cardiovascular event (MACE) was defined as a composite of all-cause mortality and unplanned hospitalization for HF. Follow-up data regarding the primary endpoints were collected until November 2018.

Results

Patients (mean age 68.7 years, male 61%) were divided into four groups as per BMI quartiles. More patients in the highest BMI group were women, were significantly younger, and had a higher prevalence of hypertension, dyslipidemia, and diabetes mellitus; however, no significant differences were observed in the prevalence of chronic kidney disease, left ventricular ejection fraction, and brain natriuretic peptide levels of the four groups. During a median follow-up duration of 583 days, 28 patients experienced all-cause mortality, and 42 were hospitalized for HF. Kaplan–Meier analysis showed that patients in the highest BMI quartiles had lower rates of MACE (Log-rank P&lt;0.05) (Figure 1). After adjusting for confounding factors, Cox regression multivariate analysis revealed that BMI was negatively and independently associated with the incidence of MACE (hazard ratio: 0.89, 95% confidence interval: 0.83–0.96, P&lt;0.05).

Conclusion

Increased BMI was associated with better clinical prognosis even in HF patients who have undergone CR Therefore, BMI assessment may be useful for risk stratification in HF patients who have undergone CR.

Figure 1. Kaplan-Meier survival curve

Funding Acknowledgement

Type of funding source: None

Elevated serum carboxy-terminal telopeptide of type I collagen predicts clinical outcome in patients with acute coronary syndrome who underwent percutaneous coronary intervention

Introduction

Serum carboxy-terminal telopeptide of type I collagen (I-CTP) is a collagen degradation product of type I collagen in the extracellular matrix of the heart, blood vessels, and bone. The serum levels of I-CTP were reportedly a predictive marker for cardiac remodeling after acute myocardial infarction. However, it remains unclear whether I-CTP can predict poor clinical outcome in patient with acute coronary syndrome (ACS).

Purpose

The aim of this study was to investigate the association between serum levels of I-CTP and clinical outcome in patients with ACS.

Methods

Serum levels of I-CTP were measured in 200 patients with ACS who underwent percutaneous coronary intervention (PCI). All patients were prospectively followed during the median follow-up period of 1312 days with the end point of major adverse cardiovascular events (MACE). We divided the patients into tertiles according to serum I-CTP level: low I-CTP group (≤4.4 ng/ml, n=72), middle I-CTP group (4.4–6.4 ng/ml, n=65), and high I-CTP group (≥6.5 ng/ml, n=63).

Results

There were 44 MACE, including 24 all-cause death and 9 rehospitalization due to heart failure. I-CTP was significantly higher in patients with MACE than those without (4.90 [interquartile range (IQR): 3.80–6.38] ng/ml vs. 6.65 [IQR: 5.00–10.08] ng/ml, p&lt;0.001). Kaplan-Meier analysis demonstrated that patients in the highest tertile of I-CTP had the greatest risk of MACE. In a univariate analysis, age, Albumin, estimated glomerular filtration rate (eGFR), low-density lipoprotein cholesterol (LDL-C), brain natriuretic peptide (BNP), high-sensitivity C-reactive protein (hsCRP) and I-CTP were significant predictors of MACE. A multivariate Cox proportional hazard analysis showed that the high I-CTP group had a higher risk for MACE (Hazard ratio [HR] 2.6, p=0.049) compared with the low I-CTP group after adjusting for confounding factors.

Conclusions

I-CTP was significantly associated with MACE, suggesting that I-CTP could be a reliable marker for clinical outcome in patients with ACS who underwent PCI.

Figure 1

Funding Acknowledgement

Type of funding source: None

Sex-related differences in clinical features and in-hospital outcomes of acute aortic dissection type b

Background

Acute aortic dissection (AAD) is a life-threatening medical condition with high morbidity and mortality. The association between female sex and poorer outcomes following surgery for AAD type A has been reported; however, the sex-related differences in clinical features and in-hospital outcomes of AAD type B remain to be elucidated.

Methods

We studied a total of 1877 patients with AAD type B who were enrolled in the Tokyo Acute Aortic Super-network from January 2013 to December 2016. Clinical features and in-hospital outcomes were compared between sexes. Independent predictors of in-hospital mortality were assessed using a multivariable analysis.

Results

The mean age of the patients was 69±13 years and 549 (29%) were females. Female patients were older than males (74±13 years vs 67±13 years; p&lt;0.001). Females had lower systolic blood pressure on admission (158±37 mmHg vs 164±38 mmHg; p=0.007) and were more likely to have altered consciousness level at presentation (8.7% vs 3.9%; p&lt;0.001), intramural hematoma (IMH)-type AAD (62.7% vs 53.6%; p&lt;0.001), and DeBakey type IIIa (28.4% vs 21.8%; p=0.002) compared with males. Females were treated with medical therapy alone more frequently (90.3% vs 85.9%; p=0.009) and had a higher in-hospital mortality rate (5.3% vs 2.6%; p=0.036). A multivariable analysis revealed that age [per year, odds ratio (OR) 1.06; 95% CI 1.04–1.09; p&lt;0.001], altered consciousness level (OR 3.28; 95% CI 1.54–6.98; p=0.002), shock/hypotension (OR 14.0; 95% CI 5.92–33.1; p&lt;0.001), classic-type AAD (OR 2.54; 95% CI 1.36–4.73; p=0.003), and medical therapy alone (OR 0.28; 95% CI 0.15–0.54; p&lt;0.001) were independent predictors of in-hospital mortality, whereas female sex was not predictive of in-hospital mortality (OR 1.64; 95% CI 0.91–2.96; p=0.10).

Conclusion

In AAD type B, females were older and had altered consciousness level, IMH-type, and a less widespread dissection more frequently than males. The overall in-hospital mortality was higher in females; however, female sex was not associated with in-hospital mortality after multivariable adjustment.

Funding Acknowledgement

Type of funding source: None

Diagnostic markers for discriminating between acute aortic dissection and acute myocardial infarction during the pre-hospital phase: analysis of 3,195 cases

 

Both acute aortic dissection (AAD) and acute myocardial infarction (AMI) present with chest pain and are life-threatening diseases that require early diagnosis and treatment for better clinical outcome. However, two critical diseases in the very acute phase are sometimes difficult to differentiate, especially prior to arrival at the hospital for urgent diagnosis and selection of specific treatment.

The aim of our study was to clarify the diagnostic markers acquired from the information gathered from medical history taking and physical examination for discriminating AAD from AMI by using data from the Tokyo Cardiovascular Care Unit (CCU) Network database.

We examined the clinical features and laboratory data of patients with AAD and AMI who were admitted to the hospital in Tokyo between January 2013 and December 2015 by using the Tokyo CCU Network database. The Tokyo CCU Network consists of &gt;60 hospitals that fulfil certain clinical criteria and receive patients from ambulance units coordinated by the Tokyo Fire Department. Of 15,061 patients diagnosed as having AAD and AMI, 3,195 with chest pain within 2 hours after symptom onset (537 AAD and 2,658 AMI) were examined. The patients with out-of-hospital cardiac arrest were excluded.

We compared the clinical data of the patients with chest pain who were diagnosed as having AAD and AMI. The following indicators were more frequent or had higher values among those with AAD: female sex (38% vs. 20%, P&lt;0.001), systolic blood pressures (SBPs) at the time of first contact by the emergency crew (142 mmHg vs. 127 mmHg), back pain in addition to chest pain (54% vs. 5%, P&lt;0.001), history of hypertension (73% vs. 58%, P&lt;0.001), SBP ≥150 mmHg (39% vs. 22%, P&lt;0.001), back pain combined with SBP ≥150 mmHg (23% vs. 0.8%, P&lt;0.001), and back pain with SBP &lt;90 mmHg (4.5% vs. 0.1%, P&lt;0.001). The following data were less frequently observed among those with AAD: diabetes mellitus (7% vs. 28%, P&lt;0.001), dyslipidaemia (17% vs. 42%, P&lt;0.001), and history of smoking (48% vs. 61%, P&lt;0.001). The multivariate regression analysis suggested that back pain with SBP ≥150 mmHg (odds ratio [OR] 47; 95% confidence interval [CI] 28–77; P&lt;0.001), back pain with SBP &lt;90 mmHg (OR 68, 95% CI 16–297, P&lt;0.001), and history of smoking (OR 0.49, 95% CI 0.38–0.63, P&lt;0.001) were the independent markers of AAD. The sensitivity and specificity of back pain with SBPs of ≥150 mmHg and back pain with SBPs &lt;90 mmHg for detecting AAD were 23% and 99%, and 4% and 99%, respectively.

In patients with chest pain suspicious of AAD and AMI, “back pain accompanied by chest pain with SBP ≥150 mmHg” or “back pain accompanied by chest pain with SBP &lt;90 mmH” is a reliable diagnostic marker of AAD with high specificity, although the sensitivity was low. The two SBP values with back pain are markers that may be useful for the ambulance crew at their first contact with patients with chest pain.

Funding Acknowledgement

Type of funding source: None

The mechanisms of age-realted difference of annual changes in ankle-brachial pressure index

 

In addition to both pulse wave velocity (PWV; a marker of arterial stiffness) and augmentation index (AI; a marker of central hemodynamics), not only the decrease of ankle-brachial pressure index (ABI) but also its increase predict the future cardiovascular events. While arterial stiffness and central hemodynamics have been proposed to affect the increase in ABI logically, their effects on increase in ABI have not been fully clarified. The present cross-sectional and longitudinal studies were conducted to examine the associations of arterial stiffness and central hemodynamics with increase in ABI and also examine the age-related difference of those associations. In 4016 men (42±9 years old), ABI, brachial-ankle PWV (baPWV) and radial AI (rAI) were measured annually for 9 years' observation period. In the cross-sectional analyses adjusted with age, heart rate and mean blood pressure, both baPWV and rAI were associated with ABI in men aged &lt;50, but not in men aged &gt;50. As shown in Figure, ABI was annually increased in subjects aged &lt;50 (n=2870), but not in those aged &gt;50 (n=1146) during the follow-up period. The mixed model linear regression analysis (MMA) conducted in 9 years' annual repeated measurement data demonstrated that increased baPWV (estimate = 0.017, p&lt;0.05) and increased rAI (estimate 0.254, p&lt;0.05) were significant determinant of annual increase of ABI (p&lt;0.01) in men aged &lt;50, but not in men aged &gt;50. In conclusion, the arterial stiffness and central hemodynamics may individually affect the increase in ABI in men aged &lt;50, but not in men &gt;50. Thus, further studies are needed to clarify whether ABI, arterial stiffness, and central hemodynamics individually predicts future cardiovascular events, and their age-related difference of their predictabilities.

figure1

Funding Acknowledgement

Type of funding source: Private hospital(s). Main funding source(s): Tokyo Medical University

Deep learning for screening of pulmonary hypertension using standard chest X-ray

Background

Early detection of pulmonary hypertension (PH) is crucial to ensure that patients receive timely treatment for the progressive clinical course. The chest X-ray (CXR), a routine method at hospitals, has recommended in order to reveal features supportive of a diagnosis of PH. However, it is well known that the sensitivity and specificity are low.

Purpose

We tested the hypothesis that application of artificial intelligence (AI) to the CXR could identify PH.

Methods

We retrospectively enrolled 900 data with paired CXR and right heart catheter (RHC), including the pulmonary artery pressure, from October 2009 to December 2018. We trained a convolutional neural network to identify patients with PH as actual value of pulmonary artery pressure, using the CXR alone (Figure). The diagnosis of PH was performed using hemodynamic measurements according to the most recent World Symposium standards: mean PAP ≥20 mmHg. We have compared the area under the curve (AUC) by human observers, measurements of CXR images, and AI for detection of PH.

Results

Subjects were divided into two groups with PH (439 patients; mean age, 66±14 years; 233 male) and without PH (461 patients; mean age, 68±12 years; 278 male). In an independent set, AI was the highest diagnostic ability for detection of PH (AUC: 0.71). The AUC by the AI algorithm was significantly higher than the AUC by measurements of CXR images and human observers (0.71 vs. 0.60 and vs. 0.63, all compared p&lt;0.05).

Conclusion

Applying AI to the CXR (a classical, universal, low-cost test) permits the CXR images to serve as a powerful tool to screen for PH.

Neural network

Funding Acknowledgement

Type of funding source: None

Identification of predictors of response to initial oral combination therapy in WHO-functional class II or III PAH patients: a post-hoc analysis of the AMBITION study

Background

AMBITION Study (NCT01178073) provided the first long-term clinical evidence for initial combination therapy with ambrisentan and tadalafil (COMB) compared with monotherapy of either agent (MONO), and the results contributed to the ESC/ERS guidelines recommending initial combination therapy in PAH patients with low and intermediate risk. However, predictors of response to initial oral combination therapy to identify PAH patients who benefit most from it have not been assessed.

Purpose

To identify potential predictors of response to initial combination therapy with ambrisentan and tadalafil (COMB) in PAH patients with WHO-FC II or III in the AMBITION study.

Methods

We examined 302 COMB patients from the modified intention to treat (mITT) population enrolled in the AMBITION study (n=605). The mITT population includes PAH patients with risk factors related to heart failure with preserved ejection fraction (Ex-PAS) who were excluded from the primary analysis set (PAS). A responder (i.e. event-free subject) was defined as not having a clinical failure event. Univariate and multivariate analyses were performed to identify the factors associated with responders. Multivariate logistic regression analysis was used to determine independent risk for each factor that showed a significant difference between cohorts by interactive backward selection. Odds ratio (OR), 95% confidence intervals (CIs) and p-values are presented.

Results

Univariate analysis showed that responders tended to be lower age, female, typical PAH (i.e. PAS), absence of coronary artery disease, non-use of oxygen therapy, and have better baseline parameters (i.e., lower NT-proBNP, longer 6-minute walk distance, low Borg index, high SaO2, WHO-FC II). A multivariate logistic regression analysis showed that female gender (OR=2.669, 95% CI: 1.291–5.518, P=0.0081), use of aldosterone antagonist diuretics (OR=2.535, 95% CI: 1.027–6.257, P=0.0436), lower log NT-proBNP (OR=0.704, 95% CI: 0.524–0.944, P=0.0190), and longer 6-minute walk distance (OR=1.006, 95% CI: 1.002–1.010, P=0.0039) were independent predictors of response to initial combination therapy.

Conclusion

These findings suggest that initial combination therapy with ambrisentan and tadalafil is beneficial, especially in less severe typical PAH patients. It also demonstrates that there is a potential contributing factor (i.e. use of aldosterone antagonist diuretics) which is not listed in the risk assessment table of the ESC/ERS guidelines.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): AMBITION study was funded by GlaxoSmithKline (GSK; study number 112565; trial registration number: NCT01178073) and Gilead Sciences, Inc. This analysis was funded by both companies.

Early detection of Niemann-pick disease type C with cataplexy and orexin levels: continuous observation with and without Miglustat

Study objectives

Niemann-Pick type C (NPC) is an autosomal recessive and congenital neurological disorder characterized by the accumulation of cholesterol and glycosphingolipids. Symptoms include hepatosplenomegaly, vertical supranuclear saccadic palsy, ataxia, dystonia, and dementia. Some cases frequently display narcolepsy-like symptoms, including cataplexy which was reported in 26% of all NPC patients and was more often recorded among late-infantile onset (50%) and juvenile onset (38%) patients. In this current study, we examined CSF orexin levels in the 10 patients of NPC with and without cataplexy, which supports previous findings.

Methods

Ten patients with NPC were included in the study (5 males and 5 females). NPC diagnosis was biochemically confirmed in all 10 patients, from which 8 patients with NPC1 gene were identified. We compared CSF orexin levels among NPC, narcoleptic and idiopathic hypersomnia patients.

Results

Six NPC patients with cataplexy had low or intermediate orexin levels. In 4 cases without cataplexy, their orexin levels were normal. In 5 cases with Miglustat treatment, their symptoms stabilized or improved. For cases without Miglustat treatment, their conditions worsened generally. The CSF orexin levels of NPC patients were significantly higher than those of patients with narcolepsy-cataplexy and lower than those of patients with idiopathic hypersomnia, which was considered as the control group with normal CSF orexin levels.

Discussion

Our study indicates that orexin level measurements can be an early alert of potential NPC. Low or intermediate orexin levels could further decrease due to reduction in the neuronal function in the orexin system, accelerating the patients’ NPC pathophysiology. However with Miglustat treatment, the orexin levels stabilized or improved, along with other general symptoms. Although the circuitry is unclear, this supports that orexin system is indeed involved in narcolepsy-cataplexy in NPC patients.

Conclusion

The NPC patients with cataplexy had low or intermediate orexin levels. In the cases without cataplexy, their orexin levels were normal. Our study suggests that orexin measurements can serve as an early alert for potential NPC; furthermore, they could be a marker of therapy monitoring during a treatment.

Elucidating three-way interactions between soil, pasture and animals that regulate nitrous oxide emissions from temperate grazing systems

Pasture-based livestock farming contributes considerably to global emissions of nitrous oxide (N2O), a powerful greenhouse gas approximately 265 times more potent than carbon dioxide. Traditionally, the estimation of N2O emissions from grasslands is carried out by means of plot-scale experiments, where externally sourced animal excreta are applied to soils to simulate grazing conditions. This approach, however, fails to account for the impact of different sward types on the composition of excreta and thus the functionality of soil microbiomes, creating unrealistic situations that are seldom observed under commercial agriculture. Using three farming systems under contrasting pasture management strategies at the North Wyke Farm Platform, an instrumented ruminant grazing trial in Devon, UK, this study measured N2O emissions from soils treated with cattle urine and dung collected within each system as well as standard synthetic urine shared across all systems, and compared these values against those from two forms of controls with and without inorganic nitrogen fertiliser applications. Soil microbial activity was regularly monitored through gene abundance to evaluate interactions between sward types, soil amendments, soil microbiomes and, ultimately, N2O production. Across all systems, N2O emissions attributable to cattle urine and standard synthetic urine were found to be inconsistent with one another due to discrepancy in nitrogen content. Despite previous findings that grasses with elevated levels of water-soluble carbohydrates tend to generate lower levels of N2O, the soil under high sugar grass monoculture in this study recorded higher emissions when receiving excreta from cattle fed the same grass. Combined together, our results demonstrate the importance of evaluating environmental impacts of agriculture at a system scale, so that the feedback mechanisms linking soil, pasture, animals and microbiomes are appropriately considered.

Sign of Hard-X-Ray Pulsation from the γ-Ray Binary System LS 5039

To understand the nature of the brightest γ-ray binary system LS 5039, hard x-ray data of the object, taken with the Suzaku and NuSTAR observatories in 2007 and 2016, respectively, were analyzed. The two data sets jointly gave tentative evidence for a hard x-ray periodicity, with a period of ∼9  s and a period increase rate by ∼3×10^{-10}  s s^{-1}. Therefore, the compact object in LS 5039 is inferred to be a rotating neutron star, rather than a black hole. Furthermore, several lines of arguments suggest that this object has a magnetic field of several times ∼10^{10}  T, two orders of magnitude higher than those of typical neutron stars. The object is hence suggested to be a magnetar, which would be the first to be found in a binary. The results also suggest that the highly efficient particle acceleration process, known to be operating in LS 5039, emerges through interactions between dense stellar winds from the massive primary star, and ultrastrong magnetic fields of the magnetar.

Publisher Correction: A weak topological insulator state in quasi-one-dimensional bismuth iodide

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Radial Spin Texture in Elemental Tellurium with Chiral Crystal Structure

The chiral crystal is characterized by a lack of mirror symmetry and inversion center, resulting in the inequivalent right- and left-handed structures. In the noncentrosymmetric crystal structure, the spin and momentum of electrons are expected to be locked in the reciprocal space with the help of the spin-orbit interaction. To reveal the spin textures of chiral crystals, we investigate the spin and electronic structure in a p-type semiconductor, elemental tellurium, with the simplest chiral structure by using spin- and angle-resolved photoemission spectroscopy. Our data demonstrate that the highest valence band crossing the Fermi level has a spin component parallel to the electron momentum around the Brillouin zone corners. Significantly, we have also confirmed that the spin polarization is reversed in the crystal with the opposite chirality. The results indicate that the spin textures of the right- and left-handed chiral crystals are hedgehoglike, leading to unconventional magnetoelectric effects and nonreciprocal phenomena.

An artificial impact on the asteroid (162173) Ryugu formed a crater in the gravity-dominated regime

The Hayabusa2 spacecraft investigated the small asteroid Ryugu, which has a rubble-pile structure. We describe an impact experiment on Ryugu using Hayabusa2's Small Carry-on Impactor. The impact produced an artificial crater with a diameter >10 meters, which has a semicircular shape, an elevated rim, and a central pit. Images of the impact and resulting ejecta were recorded by the Deployable CAMera 3 for >8 minutes, showing the growth of an ejecta curtain (the outer edge of the ejecta) and deposition of ejecta onto the surface. The ejecta curtain was asymmetric and heterogeneous and it never fully detached from the surface. The crater formed in the gravity-dominated regime; in other words, crater growth was limited by gravity not surface strength. We discuss implications for Ryugu's surface age.

Transanal repair of rectocele: prospective assessment of functional outcome and quality of life

AIM

This study aimed to assess the functional outcome of transanal repair of rectocele using patient symptom scores and quality of life (QOL) instruments.

METHOD

Patients who underwent transanal repair for symptomatic rectocele between February 2012 and August 2017 were included. This study was a retrospective analysis of prospectively collected data. A standard questionnaire including the Constipation Scoring System (CSS), the Fecal Incontinence Severity Index (FISI) and QOL instruments [Patient Assessment of Constipation (PAC)-QOL, Fecal Incontinence QOL Scale, Short-Form 36 Health Survey (SF-36)] was administered before and after the operation. Physiological assessment and proctography were performed before and after the operation.

RESULTS

Thirty patients were included. The median follow-up was 36 (6-72) months. Postoperative proctography showed a reduction in rectocele size [34 mm (14-52 mm) vs 10 mm (0-28 mm), P < 0.0001]. Physiological assessment showed no significant postoperative changes. Constipation was improved in 15/21 patients (71%) at 1 year and 14/20 patients (70%) at the mid-term follow-up. The CSS score reduced at 3 months [12 (8-12) vs 6 (1-12), P < 0.0001] and remained significantly reduced over time until the mid-term follow-up. Faecal incontinence was improved in two-thirds patients at 1 year. Four patients developed new-onset faecal incontinence. All the PAC-QOL scale scores significantly improved over time until 1 year, while two of the eight SF-36 scale scores showed significant postoperative improvement.

CONCLUSION

Transanal repair for rectocele improves constipation and constipation-specific QOL.

Conversion of a conventional superconductor into a topological superconductor by topological proximity effect

Realization of topological superconductors (TSCs) hosting Majorana fermions is a central challenge in condensed-matter physics. One approach is to use the superconducting proximity effect (SPE) in heterostructures, where a topological insulator contacted with a superconductor hosts an effective p-wave pairing by the penetration of Cooper pairs across the interface. However, this approach suffers a difficulty in accessing the topological interface buried deep beneath the surface. Here, we propose an alternative approach to realize topological superconductivity without SPE. In a Pb(111) thin film grown on TlBiSe₂, we discover that the Dirac-cone state of substrate TlBiSe₂ migrates to the top surface of Pb film and obtains an energy gap below the superconducting transition temperature of Pb. This suggests that a Bardeen-Cooper-Schrieffer superconductor is converted into a TSC by the topological proximity effect. Our discovery opens a route to manipulate topological superconducting properties of materials.

Realizing topological superconductivity is essential for applicable fault-tolerant quantum computation. Here, Trang et al. report migration of Dirac-cone from TlBiSe₂ substrate to top surface of superconducting Pb film due to topological proximity effect, suggesting realization of topological superconductivity.

540 Assessment of left ventricular ejection fraction from echocardiographic images using machine learning algorithm

Background

Precise and reliable echocardiographic assessment of LVEF is needed for clinical decision-making. LVEF is currently determined through an observer dependent process that requires manual tracing. To remove this manual tracing step, which is both time-consuming and user dependent, automatic computer aided diagnosis systems may be useful in the clinical setting.

Purpose

The aim of this study was to evaluate whether a 3-dimensional convolutional neural networks (3DCNN) could estimate left ventricular ejection fraction (LVEF) and differentiate types of heart failure (preserved EF/reduced EF) using conventional 2-dimensional echocardiographic images.

Methods

We developed a deep learning model to automatically estimate LVEF from echocardiographic data. The 3DCNN model was trained on a dataset of 340 patients. The dataset creation consisted of three main steps: firstly, for each exam, cine-loops showing the parasternal and apical views were manually selected; then, 10 sequential frames were extracted from each 1 beat and; finally, each frame was pre-processed to fit the learning model. Each patient has 2 views, resulting in a total of 6,800 images. Reference LVEF measurement was calculated by two highly experienced readers in each case.

Results

A good correlation was found between estimated LVEF based on apical 2 and 4 chamber views and reference LVEF (r =0.88, p &lt;0.001) (Figure). For classification of heart failure types based on LVEF (LVEF ≥50% or &lt;50%), the area under the receiver-operating characteristic curve by the 3DCNN algorithm was over 0.95.

Conclusions

The 3DCNN can be applied to estimate and classify the LVEF in the clinical setting. Furthermore, this work will serve as a driver for future research using million image databases.

Abstract 540 Figure.