Fine-Structure Qubit Encoded in Metastable Strontium Trapped in an Optical Lattice

We demonstrate coherent control of the fine-structure qubit in neutral strontium atoms. This qubit is encoded in the metastable ^{3}P_{2} and ^{3}P_{0} states, coupled by a Raman transition. Using a magnetic quadrupole transition, we demonstrate coherent state initialization of this THz qubit. We show Rabi oscillations with more than 60 coherent cycles and single-qubit rotations on the μs scale. With spin echo, we demonstrate coherence times of tens of ms. Our results pave the way for fast quantum information processors and highly tunable quantum simulators with two-electron atoms.

Radial localization of electron temperature pedestal and ELM-like events using ECE measurements at Wendelstein 7-X

A magnetic configuration scan was performed at Wendelstein 7-X stellarator by varying the rotational transform to analyze the plasma confinement for magnetic configurations with different edge magnetic island locations and sizes. For the magnetic configurations, where the 5/5 island chain was moved inside the last closed flux surface, it was observed with electron cyclotron emission measurements that an electron temperature, Te, pedestal develops in the plasma buildup phase and followed by the edge localized mode (ELM)-like crashes. From the mapping of the island to the plasma radius from HINT equilibrium, it was found that the Te pedestal is formed at the island location on the high field side of the plasma. The ELM-like crashes occur at the location of the pedestal and the transport barrier is broken typically with an energy loss of 3-4% during a single ELM-like event. The frequency and the amplitude of the ELM-like crashes were observed to be changing with island size, plasma heating power and density. Additionally during the plasma decay, after the heating was switched-off, a transition to degraded plasma confinement state was observed with changed Te profile gradients, faster decay rate of diamagnetic energy, and increased H-alpha levels.

Tumor mimicking gastric ulcer penetrating asymptomatically into the pancreas

Gastroduodenal ulcer disease is characterized by ulceration of the stomach or duodenum, with ulcer lesions occurring more frequently in the duodenum. Serious complications of this disease include bleeding, perforation of the ulcer and penetration into surrounding organ. Our report presents the case of an older man who had a gastric ulcer penetrating into the pancreas. This was not diagnosed at the time of the penetration. The patient came to our care for recurrent hematemesis without a proven source of bleeding. During the diagnostic process, the presence of an intramural gastric tumor was suspected. An excision of the suspected lesion was successfully performed at our clinic, followed by histological confirmation of perforated ulcer. The postoperative course was complicated by the development of a pancreatic fistula. However, conservative treatment resulted in complete recovery of the patient.

Impact of Magnetic Field Configuration on Heat Transport in Stellarators and Heliotrons

We assess the magnetic field configuration in modern fusion devices by comparing experiments with the same heating power, between a stellarator and a heliotron. The key role of turbulence is evident in the optimized stellarator, while neoclassical processes largely determine the transport in the heliotron device. Gyrokinetic simulations elucidate the underlying mechanisms promoting stronger ion scale turbulence in the stellarator. Similar plasma performances in these experiments suggests that neoclassical and turbulent transport should both be optimized in next step reactor designs.

Demonstration of reduced neoclassical energy transport in Wendelstein 7-X

Research on magnetic confinement of high-temperature plasmas has the ultimate goal of harnessing nuclear fusion for the production of electricity. Although the tokamak1 is the leading toroidal magnetic-confinement concept, it is not without shortcomings and the fusion community has therefore also pursued alternative concepts such as the stellarator. Unlike axisymmetric tokamaks, stellarators possess a three-dimensional (3D) magnetic field geometry. The availability of this additional dimension opens up an extensive configuration space for computational optimization of both the field geometry itself and the current-carrying coils that produce it. Such an optimization was undertaken in designing Wendelstein 7-X (W7-X)2, a large helical-axis advanced stellarator (HELIAS), which began operation in 2015 at Greifswald, Germany. A major drawback of 3D magnetic field geometry, however, is that it introduces a strong temperature dependence into the stellarator's non-turbulent 'neoclassical' energy transport. Indeed, such energy losses will become prohibitive in high-temperature reactor plasmas unless a strong reduction of the geometrical factor associated with this transport can be achieved; such a reduction was therefore a principal goal of the design of W7-X. In spite of the modest heating power currently available, W7-X has already been able to achieve high-temperature plasma conditions during its 2017 and 2018 experimental campaigns, producing record values of the fusion triple product for such stellarator plasmas3,4. The triple product of plasma density, ion temperature and energy confinement time is used in fusion research as a figure of merit, as it must attain a certain threshold value before net-energy-producing operation of a reactor becomes possible1,5. Here we demonstrate that such record values provide evidence for reduced neoclassical energy transport in W7-X, as the plasma profiles that produced these results could not have been obtained in stellarators lacking a comparably high level of neoclassical optimization.

Feasibility of non-gated dynamic fetal cardiac MRI for identification of fetal cardiovascular anatomy

Funding Acknowledgements

Type of funding sources: None.

Purpose

We sought to retrospectively evaluate the feasibility of identifying the fetal cardiac and thoracic vascular structures with non-gated dynamic balanced steady-state free precession MRI sequences.

Methods

We retrospectively assessed the visibility of cardiovascular anatomy in 66 fetuses without suspicion of congenital heart defect (mean gestational age 27+/- 4, range 21-38 weeks). Non-gated dynamic balanced steady-state free precession (SSFP) sequences were acquired in three planes (axial, coronal and sagittal) of the fetal thorax (slice thickness 4-5mm, FOV 400, FA 60°, matrix 256x256). The images were analysed following a segmental approach in consensus reading by an experienced paediatric cardiologist and radiologist. An imaging score was defined by giving one point to each visualized structure. Basic diagnostic structures included the atria, ventricles, systemic veins, right and left ventricular outflow tracts (RVOT/LVOT), aortic arch, descending aorta (DAO), ductus arteriosus and thymus (12 points); advanced diagnostic features included the atrioventricular (AV) valves, pulmonary arteries and veins, supraaortic arteries and trachea, yielding a maximum score of 21 points. Image quality was rated from 0 (poor) to 2 (good). The influence of gestational age (GA), field strength, placenta position, and maternal panniculus on image quality and imaging score were tested.

Results

34 scans were performed at 1.5 T, 32 at 3 T. Heart position, atria and ventricles could be seen in all 66 fetuses. Basic diagnosis (>12 points) was achieved in 60 (90%) cases, with visualization of the IVC and SVC in 65 (98%) and 63 (95%), RVOT in 62 (94%), LVOT in 61 (92%), aortic arch in 60 (91%), DAO in 64 (97%), ductus arteriosus in 59 (89%) and thymus in 50 (76%) fetuses. The AV valves were recognised in 55 (83%), the pulmonary arteries in 35 (53%), at least one pulmonary vein in 46 (70%), the supraaortic arteries in 42 (64%), and the trachea in 59 (89%) fetuses. The mean imaging score was 16.8 +/- 3.7. Maternal panniculus (r -0.3; p 0.01) and gestational age (r 0.6; p < 0.001) correlated with imaging score. Field strength influenced image quality, with 1.5 T being better than 3T images (p 0.04), but not the total imaging score. Imaging score or quality were independent from placenta position.

Conclusions

Fetal heart MRI with a non-gated SSFP sequence in multiple planes enables recognition of basic cardiovascular anatomy. Advanced diagnostics may be limited by thick maternal panniculus, lower GA and higher field strength.

Deep learning for diagnosis and survival prediction in soft tissue sarcoma

BACKGROUND

Clinical management of soft tissue sarcoma (STS) is particularly challenging. Here, we used digital pathology and deep learning (DL) for diagnosis and prognosis prediction of STS.

PATIENTS AND METHODS

Our retrospective, multicenter study included a total of 506 histopathological slides from 291 patients with STS. The Cancer Genome Atlas cohort (240 patients) served as training and validation set. A second, multicenter cohort (51 patients) served as an additional test set. The use of the DL model (DLM) as a clinical decision support system was evaluated by nine pathologists with different levels of expertise. For prognosis prediction, 139 slides from 85 patients with leiomyosarcoma (LMS) were used. Area under the receiver operating characteristic (AUROC) and accuracy served as main outcome measures.

RESULTS

The DLM achieved a mean AUROC of 0.97 (±0.01) and an accuracy of 79.9% (±6.1%) in diagnosing the five most common STS subtypes. The DLM significantly improved the accuracy of the pathologists from 46.3% (±15.5%) to 87.1% (±11.1%). Furthermore, they were significantly faster and more certain in their diagnosis. In LMS, the mean AUROC in predicting the disease-specific survival status was 0.91 (±0.1) and the accuracy was 88.9% (±9.9%). Cox regression showed the DLM's prediction to be a significant independent prognostic factor (P = 0.008, hazard ratio 5.5, 95% confidence interval 1.56-19.7) in these patients, outperforming other risk factors.

CONCLUSIONS

DL can be used to accurately diagnose frequent subtypes of STS from conventional histopathological slides. It might be used for prognosis prediction in LMS, the most prevalent STS subtype in our cohort. It can also help pathologists to make faster and more accurate diagnoses. This could substantially improve the clinical management of STS patients.

Clinical application of ultrashort echo-time MRI for lung pathologies in children

Lung magnetic resonance imaging (MRI) is considered to be challenging, because the low proton density of the tissue, fast signal decay, and respiratory artefacts hamper adequate image quality. MRI of the lungs and thorax is increasingly used in the paediatric population, because it is a radiation-free alternative to chest CT. Recently, ultrashort echo-time (UTE) sequences have been introduced into clinical MRI protocols, in order to improve the contrast-to-noise ratio due to reduced susceptibility artefacts and to depict structural alterations comparable to CT. The purpose of this review is to provide an overview of various clinical conditions and pathologies in the paediatric chest depicted by an UTE sequence, the so-called three-dimensional (3D) Cones sequence, in comparison with conventional MRI sequences. Besides describing typical features of cystic fibrosis, we present UTE application in other more or less common paediatric lung pathologies, for instance, interstitial pneumopathies, pulmonary infections, and congenital pulmonary malformations.

Morgagni hernia - case reports

Morgagni hernia is a rare form of diaphragmatic hernia. It is a congenital defect of the diaphragm, often asymptomatic in adulthood and thus usually found only incidentally. Its treatment is predominantly surgical. This article presents three case reports of patients operated in our department.

Turbulence Mechanisms of Enhanced Performance Stellarator Plasmas

We theoretically assess two mechanisms thought to be responsible for the enhanced performance observed in plasma discharges of the Wendelstein 7-X stellarator experiment fueled by pellet injection. The effects of the ambipolar radial electric field and the electron density peaking on the turbulent ion heat transport are separately evaluated using large-scale gyrokinetic simulations. The essential role of the stellarator magnetic geometry is demonstrated, by comparison with a tokamak.

Stellarators Resist Turbulent Transport on the Electron Larmor Scale

Electron temperature gradient (ETG)-driven turbulence, despite its ultrafine scale, is thought to drive significant thermal losses in magnetic fusion devices-but what role does it play in stellarators? The first numerical simulations of ETG turbulence for the Wendelstein 7-X stellarator, together with power balance analysis from its initial experimental operation phase, suggest that the associated transport should be negligible compared to other channels. The effect, we argue, originates essentially from the geometric constraint of multiple field periods, a generic feature of stellarators.

Mixed-methods assessment of surgical capacity in two regions in Ethiopia

Background

Surgery is among the most neglected parts of healthcare systems in low- and middle-income countries. Ethiopia has launched a national strategic plan to address challenges in the surgical system. This study aimed to assess surgical capacity in two Ethiopian regions to inform priority areas for improvement.

Methods

A mixed-methods study was conducted using two tools adapted from the Lancet Commission's Surgical Assessment Tools: a quantitative Hospital Assessment Tool and a qualitative semistructured interview tool. Fifteen hospitals selected by the Federal Ministry of Health were surveyed in the Tigray and Amhara regions to assess the surgical system across five domains: service delivery, infrastructure, workforce, information management and financing.

Results

Service delivery was low across hospitals with a mean(s.d.) of 5(6) surgical cases per week and a narrow range of procedures performed. Hospitals reported varying availability of basic infrastructure, including constant availability of electricity (9 of 15) and running water (5 of 15). Unavailable or broken diagnostic equipment was also common. The majority of surgical and anaesthesia services were provided by non-physician clinicians, with little continuing education available. All hospitals tracked patient-level data regularly and eight of 15 hospitals reported surgical volume data during the assessment, but research activities were limited. Hospital financing specified for surgery was rare and the majority of patients must pay out of pocket for care.

Conclusion

Results from this study will inform programmes to simultaneously improve each of the health system domains in Ethiopia; this is required if better access to and quality of surgery, anaesthesia and obstetric services are to be achieved.

Tendon healing induced by chemically modified mRNAs

Tendon disorders are frequent both in human and veterinary medicine with high re-injury rates and unsatisfactory therapeutic treatments. Application of naked, chemically-modified mRNA (cmRNA), encoding for therapeutic proteins, is an innovative approach to address tendon healing. In the current study, we demonstrated that injection of naked cmRNA, diluted in a glucose-containing solution, into tendons resulted in high protein expression in healthy and experimentally-injured tendons. Injection of bone morphogenetic protein 7 (BMP-7)-encoding cmRNA resulted in a significantly higher expression of BMP-7 protein and reduced formation of collagen type III, compared to vehicle control. Moreover, in a large animal model, reporter protein expression was detectable not only in healthy, but also in experimentally-injured, severely inflamed tendons. Summarising, these results demonstrated the potential of cmRNAs encoding for therapeutic proteins as a new class of drugs for the treatment of tendon disorders.

MicroRNAs in metabolism

MicroRNAs (miRNAs) have within the past decade emerged as key regulators of metabolic homoeostasis. Major tissues in intermediary metabolism important during development of the metabolic syndrome, such as β-cells, liver, skeletal and heart muscle as well as adipose tissue, have all been shown to be affected by miRNAs. In the pancreatic β-cell, a number of miRNAs are important in maintaining the balance between differentiation and proliferation (miR-200 and miR-29 families) and insulin exocytosis in the differentiated state is controlled by miR-7, miR-375 and miR-335. MiR-33a and MiR-33b play crucial roles in cholesterol and lipid metabolism, whereas miR-103 and miR-107 regulates hepatic insulin sensitivity. In muscle tissue, a defined number of miRNAs (miR-1, miR-133, miR-206) control myofibre type switch and induce myogenic differentiation programmes. Similarly, in adipose tissue, a defined number of miRNAs control white to brown adipocyte conversion or differentiation (miR-365, miR-133, miR-455). The discovery of circulating miRNAs in exosomes emphasizes their importance as both endocrine signalling molecules and potentially disease markers. Their dysregulation in metabolic diseases, such as obesity, type 2 diabetes and atherosclerosis stresses their potential as therapeutic targets. This review emphasizes current ideas and controversies within miRNA research in metabolism.

Overview of diagnostic performance and results for the first operation phase in Wendelstein 7-X (invited)

Wendelstein 7-X, a superconducting optimized stellarator built in Greifswald/Germany, started its first plasmas with the last closed flux surface (LCFS) defined by 5 uncooled graphite limiters in December 2015. At the end of the 10 weeks long experimental campaign (OP1.1) more than 20 independent diagnostic systems were in operation, allowing detailed studies of many interesting plasma phenomena. For example, fast neutral gas manometers supported by video cameras (including one fast-frame camera with frame rates of tens of kHz) as well as visible cameras with different interference filters, with field of views covering all ten half-modules of the stellarator, discovered a MARFE-like radiation zone on the inboard side of machine module 4. This structure is presumably triggered by an inadvertent plasma-wall interaction in module 4 resulting in a high impurity influx that terminates some discharges by radiation cooling. The main plasma parameters achieved in OP1.1 exceeded predicted values in discharges of a length reaching 6 s. Although OP1.1 is characterized by short pulses, many of the diagnostics are already designed for quasi-steady state operation of 30 min discharges heated at 10 MW of ECRH. An overview of diagnostic performance for OP1.1 is given, including some highlights from the physics campaigns.

[Diagnosis and treatment of billiary ileus]

INTRODUCTION

Biliary ileus represents only 14% of mechanical obstructions of the gastrointestinal tract. However, the rate of non-strangulated small bowel obstructions reaches as much as 25% in patients over 65 years of age. Usually, a pressure necrosis is created by a large gallstone that passes through the developed biliodigestive fistula, subsequently obturating the gastrointestinal tract.

CASE REPORTS

35 patients underwent a surgical procedure at the Department of Surgery, Teaching Hospital Pilsen for biliary ileus from January 1, 2000 to January 31, 2015. Mean age was 79 years (median 78 years; min. 58 years; max. 92 years). Aerobilia was visible in abdominal X-ray scans in 7 cases (26%) of 27 acquired images. Preoperatively, colonoscopy was done 2 times and esophagogastroduodenoscopy 9 times. Regarding surgical procedures, enterolithotomy was done in 21 cases, extraction of the gallstone from gastrotomy was done 3 times, small bowel resection 7 times, Hartmann resection 1 time, resection of ileoascendentoanastomosis 1 time, and extraction of the gallstone from duodenotomy with duodenojejunoanastomosis and cholecystectomy was done in 1 case. Ileotransversoanastomosis was performed in 1 case. Postoperative 30-day mortality was 14.3%. Postoperative morbidity according Clavien-Dindo was 22.8% for grade 1, 5.7% for grade 2, 11.5% for grade 3, and 11.5% for grade 4. A recurrence was observed in 8.8%. Primary treatment of the fistula and cholecystectomy were done in 1 case.

CONCLUSION

The indication of primary biliodigestive fistula treatment always depends on the general condition of the patient and on the local finding in the gallbladder area. Residual fistula increases the risk of reccurence, but primary treatment is associated with higher mortality. It is also important to duly revise the entire bowel to avoid an early reccurence due to multiple gallstones.

KEY WORDS

biliary ileus diagnosis treatment.

[Coincidence of colonic lymphoma and gallstone ileus - case report]

INTRODUCTION

Primary colonic lymphoma is a very rare malignant disease of the gastrointestinal tract, accounting for 14% of all malignant diseases in this location. It is classified in the group of extranodal lymphomas; its long-term asymptomatic progression makes it different from common colorectal carcinomas making its diagnosis very difficult, more often accidental. Gallstone ileus is quite an uncommon complication of cholecystolithiasis diagnosed with difficulty. Up to 50% of cases are diagnosed during surgery. The obturated location depends on the size of the stone, location of the conjunction between the biliary and gastrointestinal tracts, and also on any preexisting stenosis due to another unknown pathology.

CASE REPORT

We present a case of an 86-year-old man treated for acute diverticulitis with typical clinical symptoms. Following further examination (colonoscopy, computed tomography) revealed a tumour-like infiltration in the sigmoid colon wall and a voluminous polyp was suspected according to the colonoscopy. Computed tomography described an obstruction by a biliary stone tumbling through the cholecystocolonic fistula. Subsequent biopsy supported the suspected malignant etiology. The patient underwent resection of the sigmoid colon sec. Hartmann; an infiltration was found in the subhepatic space, which corresponded to the described fistulisation between the biliary tract and the colon. A large 40 mm gallstone was found in the resected sigmoid colon over the stenosis and the bowel wall showed diffuse thickening with several polyps; final histopathological assessment confirmed malignant lymphoma of the plasmocytoma type. No serious complications occurred in the postoperative period; after healing, the patient was transferred to hematooncology care.

CONCLUSION

The article describes the presence of two rare diseases - colonic lymphoma and gallstone ileus. Clearly, without the biliary stone obstruction in the preexisting tumorous stenosis in the sigmoid colon, the malignant hematooncology disease would not have been diagnosed.

KEY WORDS

primary colonic lymphoma - gallstone ileus - complication of the cholecystolithiasis - extranodal lymphoma - acute diverticulitis.

[Mediastinitis after esophageal perforation]

INTRODUCTION

Assessment of therapy in patients with mediastinal infection resulting from esophageal perforation.

MATERIAL AND METHODS

Retrospective (2008-2012) processing of a group of surgically treated patients. The aspects assessed were aetiology, the surgical methods applied and the length of therapy.

RESULTS

The total number of patients treated was 16. In 8 cases, the aetiology was iatrogenic (3 cases of leaking esophageal anastomosis in consequence of resection of the esophagus, 2 cases of perforation after fundoplication, 1 case of esophageal cardiomyotomy, and 2 cases of perforation during endoscopy). In 4 patients, the aetiology was spontaneous perforation, impacted foreign bodies caused difficulties to 3 patients, and the last cause was acid corrosive esophagitis. A stent was applied in all the patients at the site of the defect. The mediastinitis was drained through the access from thoracotomy or left thoracolaparotomy, respectively (8 cases), or by combination of laparotomy/laparostomy and pleural drainage (5 cases). Pleural (in 3 cases) and neck (1 case) drainage meant minimum intervention. Esophagectomy was not carried out in any of the patients. 4 patients died. The average period of time for which the stent was left in situ was 53.7 days; the average time of hospitalization in surviving patients was 53.4 days.

CONCLUSION

Stent application does not show any difference regarding patients' survival (25% mortality), but enables shortening the total therapy time and, predominantly, preserving the native esophagus.