Spins in silicon quantum devices are promising candidates for large-scale quantum computing. Gate-based sensing of spin qubits offers a compact and scalable readout with high fidelity, however, ...further improvements in sensitivity are required to meet the fidelity thresholds and measurement timescales needed for the implementation of fast feedback in error correction protocols. Here, we combine radio-frequency gate-based sensing at 622 MHz with a Josephson parametric amplifier, that operates in the 500-800 MHz band, to reduce the integration time required to read the state of a silicon double quantum dot formed in a nanowire transistor. Based on our achieved signal-to-noise ratio, we estimate that singlet-triplet single-shot readout with an average fidelity of 99.7% could be performed in 1 μs, well below the requirements for fault-tolerant readout and 30 times faster than without the Josephson parametric amplifier. Additionally, the Josephson parametric amplifier allows operation at a lower radio-frequency power while maintaining identical signal-to-noise ratio. We determine a noise temperature of 200 mK with a contribution from the Josephson parametric amplifier (25%), cryogenic amplifier (25%) and the resonator (50%), showing routes to further increase the readout speed.
We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of ...physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Efficient and selective molecular syntheses are paramount to inter alia biomolecular chemistry and material sciences as well as for practitioners in chemical, agrochemical, and pharmaceutical ...industries. Organic electrosynthesis has undergone a considerable renaissance and has thus in recent years emerged as an increasingly viable platform for the sustainable molecular assembly. In stark contrast to early strategies by innate reactivity, electrochemistry was recently merged with modern concepts of organic synthesis, such as transition-metal-catalyzed transformations for inter alia C–H functionalization and asymmetric catalysis. Herein, we highlight the unique potential of organic electrosynthesis for sustainable synthesis and catalysis, showcasing key aspects of exceptional selectivities, the synergism with photocatalysis, or dual electrocatalysis, and novel mechanisms in metallaelectrocatalysis until February of 2021.
We perform a new global analysis of spin-dependent parton distribution functions with the inclusion of Ioffe time pseudo-distributions computed in lattice QCD (LQCD), which are directly sensitive to ...the gluon helicity distribution, Δg. These lattice data have an analogous relationship to parton distributions as do experimental cross sections, and can be readily included in global analyses. We focus in particular on the constraining capability of current LQCD data on the sign of Δg at intermediate parton momentum fractions x, which was recently brought into question by analysis of data in the absence of parton positivity constraints. We find that present LQCD data cannot discriminate between positive and negative Δg solutions, although significant changes in the solutions for both the gluon and quark sectors are observed.
Merons which are topologically equivalent to one-half of skyrmions can exist only in pairs or groups in two-dimensional (2D) ferromagnetic (FM) systems. The recent discovery of meron lattice in ...chiral magnet Co
Zn
Mn
raises the immediate challenging question that whether a single meron pair, which is the most fundamental topological structure in any 2D meron systems, can be created and stabilized in a continuous FM film? Utilizing winding number conservation, we develop a new method to create and stabilize a single pair of merons in a continuous Py film by local vortex imprinting from a Co disk. By observing the created meron pair directly within a magnetic field, we determine its topological structure unambiguously and explore the topological effect in its creation and annihilation processes. Our work opens a pathway towards developing and controlling topological structures in general magnetic systems without the restriction of perpendicular anisotropy and Dzyaloshinskii-Moriya interaction.
Failure of T cells to protect against cancer is thought to result from lack of antigen recognition, chronic activation, and/or suppression by other cells. Using a mouse sarcoma model, we show that ...glucose consumption by tumors metabolically restricts T cells, leading to their dampened mTOR activity, glycolytic capacity, and IFN-γ production, thereby allowing tumor progression. We show that enhancing glycolysis in an antigenic “regressor” tumor is sufficient to override the protective ability of T cells to control tumor growth. We also show that checkpoint blockade antibodies against CTLA-4, PD-1, and PD-L1, which are used clinically, restore glucose in tumor microenvironment, permitting T cell glycolysis and IFN-γ production. Furthermore, we found that blocking PD-L1 directly on tumors dampens glycolysis by inhibiting mTOR activity and decreasing expression of glycolysis enzymes, reflecting a role for PD-L1 in tumor glucose utilization. Our results establish that tumor-imposed metabolic restrictions can mediate T cell hyporesponsiveness during cancer.
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•Tumor cells and TILs compete for glucose within the tumor niche•Metabolic competition can drive cancer progression•Checkpoint blockade antibodies alter the metabolic balance in a tumor•PD-L1 promotes Akt/mTOR activation and glycolysis in tumor cells
Glucose consumption by antigenic tumors can metabolically restrict T cells, directly dampening their effector function and allowing tumor progression. Checkpoint blockade therapy may correct this resource imbalance through a direct effect in the tumor cells.
Advancements in reconstructive microsurgery have evolved into supermicrosurgery; connecting vessels with diameter between 0.3 and 0.8 mm for reconstruction of lymphatic flow and vascularized tissue ...transplantation. Supermicrosurgery is limited by the precision and dexterity of the surgeon's hands. Robot assistance can help overcome these human limitations, thereby enabling a breakthrough in supermicrosurgery. We report the first-in-human study of robot-assisted supermicrosurgery using a dedicated microsurgical robotic platform. A prospective randomized pilot study is conducted comparing robot-assisted and manual supermicrosurgical lymphatico-venous anastomosis (LVA) in treating breast cancer-related lymphedema. We evaluate patient outcome at 1 and 3 months post surgery, duration of the surgery, and quality of the anastomosis. At 3 months, patient outcome improves. Furthermore, a steep decline in duration of time required to complete the anastomosis is observed in the robot-assisted group (33-16 min). Here, we report the feasibility of robot-assisted supermicrosurgical anastomosis in LVA, indicating promising results for the future of reconstructive supermicrosurgery.
Purpose
Breast cancer-related lymphedema (BCRL) is caused by an interruption of the lymphatic system after breast cancer treatment. Lymphaticovenous anastomosis (LVA), by which one or more patent ...lymphatic collecting vessels are connected to subcutaneous veins, shows promising results. Postoperatively, the patency of these anastomosis can be evaluated; however, little is known concerning the long-term patency after LVA in patients with BCRL. The aim of this study was to analyse the long-term patency, quality of life (QoL) and arm circumference after LVA, and to explore differences between patent and non-patent anastomosis and its correlation with clinical improvement.
Methods
Twenty-five patients underwent indocyanine green (ICG) lymphography, lymph ICF-questionnaire, and arm circumference measurement preoperatively and 12 months after the LVA procedure.
Results
Seventy-six percent of the patients showed at least one patent anastomosis after 12 months. Quality of life according to the Lymph-ICF increased significantly (
p
< 0.000); however, arm circumference showed no significant decrease. Sixty-five percent discontinued wearing compression stockings. The patent anastomosis group, compared with the non-patent anastomosis group showed, without significance, more improvement in QoL, arm circumference, and discontinuation of compression stockings, as well as a lower rate of infections both pre- and postoperatively, a shorter duration of lymphedema preoperatively, and a higher rate of early lymphedema and ICG stage.
Conclusions
LVA showed an acceptable patency and positive correlation between a patent anastomosis and clinical improvement after 12 months. Further research with a larger study population is required to determine whether outcomes or patient characteristics significantly correlate with a patent anastomosis after LVA operation.
Breast cancer related lymphedema (BCRL) is a chronic condition with a detrimental impact on psychosocial and physical well-being. Lymphaticovenous anastomosis has shown promising results in ...alleviating physical symptoms and increasing quality of life in patients with BCRL. The aim of the study is to evaluate the effect on health related quality of life (HrQol) after LVA surgery versus conservative treatment in patients with BCRL. The study is a prospective, multicenter randomized controlled trial. Adult women with unilateral BCRL, with early stage lymphedema and viable lymphatic vessels were included. The primary outcome measure was HrQol measured by the lymphedema functioning disability and health (Lymph-ICF) questionnaire. The secondary outcomes were volume difference measured by the water displacement method; the Upper Extremity Lymphedema (UEL) index; and daily use of the compression garments after 3 and 6 months. For this interim analysis 46 patients per group were included. There was a significant improvement in the domains in physical and mental function in the Lymph-ICF questionnaire in the LVA group after 6 months, (- 16.46 ± 18.5, p < 0.05, - 10.12 ± 29.5, p < 0.05 respectively). However, there was no statistical difference in the total score of the Lymph-ICF after 6 months in both groups (LVA-group; - 8.57 ± 22.6, p > 0.05, CDT-group; - 2.65 ± 18.2, p < 0.05). Furthermore, there was no significant volume reduction in both groups (LVA-group: 20.04 ± 196.40, p = 0.497, CDT: 33.98 ± 189.87, p = 0.236). In the LVA group, 41% partially of completely stopped wearing the compression garments after six months whereas in the CDT group 0% discontinued to use of compression garments. LVA resulted in improvement of the domains physical and mental function of the Lymph-ICF. Limb volume did not significantly improve after 6 months. However, around 42% could completely or partially stopped with the use of compression garments in the LVA group. The current results are promising, however longer follow up is required to assess long term effect of LVA for secondary lymphedema. Clinical Trial Registration: NCT02790021 registered on 03/06/2016.
Thermal fluid dynamics and experiments have been used to study the evolution of pores during selective laser melting of Ti-6Al-4V. Scanning electron micrographs show that the morphology of pores ...changed from near-spherical to elongated shape as the laser scan speed increased. Computational fluid dynamics suggests that this is caused by the change of flow pattern in the melt pool which is dictated by forces such as vapour pressure, gravitational force, capillary and thermal capillary forces exerted on the metallic/gaseous interface.
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