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Quantum computing crucially relies on the ability to efficiently characterize the quantum states output by quantum hardware. Conventional methods which probe these states through direct measurements and classically computed correlations become computationally expensive when increasing the system size. Quantum neural networks tailored to recognize specific features of quantum states by combining unitary operations, measurements and feedforward promise to require fewer measurements and to tolerate errors. Here, we realize a quantum convolutional neural network (QCNN) on a 7-qubit superconducting quantum processor to identify symmetry-protected topological (SPT) phases of a spin model characterized by a non-zero string order parameter. We benchmark the performance of the QCNN based on approximate ground states of a family of cluster-Ising Hamiltonians which we prepare using a hardware-efficient, low-depth state preparation circuit. We find that, despite being composed of finite-fidelity gates itself, the QCNN recognizes the topological phase with higher fidelity than direct measurements of the string order parameter for the prepared states. Quantum neural networks could help analysing the output of quantum computers and quantum simulators of growing complexity. Here, the authors use a 7-qubit superconducting quantum processor to show how a quantum convolutional neural network can correctly recognise the phase of a quantum many-body state.

We study entanglement of the motional degrees of freedom of two tethered and optically trapped microdisks inside a single cavity. By properly choosing the position of the trapped objects in the optical cavity and driving proper modes of the cavity, it is possible to equip the system with linear and quadratic optomechanical couplings. We show that a parametric coupling between the fundamental vibrational modes of two tethered microdisks can be generated via a time-modulated input laser. For a proper choice of the modulation frequency, this mechanism can drive the motion of the microdisks into an inseparable state in the long time limit via a two-mode squeezing process. We numerically confirm the performance of our scheme for current technology and briefly discuss an experimental setup that can be used for detecting this entanglement by employing the quadratic coupling. We also comment on the perspectives for generating such entanglement between the oscillations of optically levitated nanospheres.

Tocopherols are lipid-soluble antioxidants synthesized in plastids of plants and other photosynthetic organisms. The four known tocopherols, 𝛼-, 𝛽-, 𝛾-, and 𝛿-tocopherol, differ in number and position of methyl groups on their chromanol head group. In unstressed Arabidopsis (Arabidopsis thaliana) leaves, 𝛼-tocopherol constitutes the main tocopherol form, whereas seeds predominantly contain 𝛾-tocopherol. Here, we show that inoculation of Arabidopsis leaves with the bacterial pathogen Pseudomonas syringae induces the expression of genes involved in early steps of tocopherol biosynthesis and triggers strong accumulation of 𝛾-tocopherol, moderate production of 𝛿-tocopherol, and generation of the benzoquinol precursors of tocopherols. The pathogen-inducible biosynthesis of tocopherols is promoted by the immune regulators ENHANCED DISEASE SUSCEPTIBILITY1 and PHYTOALEXIN-DEFICIENT4. In addition, tocopherols accumulate in response to bacterial flagellin and reactive oxygen species. By quantifying tocopherol forms in inoculated wild-type plants and biosynthetic pathway mutants, we provide biochemical insights into the pathogen-inducible tocopherol pathway. Notably, vitamin E deficient2 (vte2) mutant plants, which are compromised in both tocopherol and benzoquinol precursor accumulation, exhibit increased susceptibility toward compatible P. syringae and possess heightened levels of markers of lipid peroxidation after bacterial infection. The deficiency of triunsaturated fatty acids in vte2-1 fatty acid desaturase3-2 (fad3-2) fad7-2 fad8 quadruple mutants prevents increased lipid peroxidation in the vte2 background and restores pathogen resistance to wild-type levels. Therefore, the tocopherol biosynthetic pathway positively influences salicylic acid accumulation and guarantees effective basal resistance of Arabidopsis against compatible P. syringae, possibly by protecting leaves from the pathogen-induced oxidation of trienoic fatty acid-containing lipids.

Observing quantum phenomena in strongly correlated many-particle systems is difficult because of the short length- and timescales involved. Exerting control over the state of individual elements within such a system is even more so, and represents a hurdle in the realization of quantum computing devices. Substantial progress has been achieved with arrays of Josephson junctions and cold atoms in optical lattices, where detailed control over collective properties is feasible, but addressing individual sites remains a challenge. Here we show that a system of polaritons held in an array of resonant optical cavities—which could be realized using photonic crystals or toroidal microresonators—can form a strongly interacting many-body system showing quantum phase transitions, where individual particles can be controlled and measured. The system also offers the possibility to generate attractive on-site potentials yielding highly entangled states and a phase with particles much more delocalized than in superfluids.

This study evaluated factors that influence the cost-effectiveness of talazoparib, particularly for patients with a germline breast-cancer-gene-(brca)-mutation and locally advanced or metastasized breast cancer within the context of the German healthcare system. We constructed a partitioned survival model to compare medical costs and treatment effectiveness for patients with such cancers over 45 months. Transition probabilities were derived from survival data from a randomized Phase-III EMBRACA trial, utilities based on published reports, and costs in Euros, which included costs for drug acquisition, clinical monitoring, and treatment of adverse events. Willingness-to-pay thresholds were set to be multiples of the current German per capita gross domestic product. Treatment with talazoparib led to a gain of 0.32 life-years (0.22 quality-adjusted life-years). The mean total cost of €84,003 for talazoparib and €12,741 for standard therapy resulted in an incremental cost-effectiveness ratio of €223,246 per life-year and €323,932 per quality-adjusted life-year gained, indicating that talazoparib is unlikely to be cost-effective at current pricing.

There is indication that the fallopian tubes might be involved in ovarian cancer pathogenesis and their removal reduces cancer risk. Hence, bilateral salpingectomy during hysterectomy or sterilization, so called opportunistic salpingectomy (OS), is gaining wide acceptance as a preventive strategy. Recently, it was discussed whether implementation of OS at other gynecologic surgery, e.g., cesarean section, endometriosis excision or myomectomy and even at non-gynecologic abdominal surgery such as cholecystectomy or appendectomy for women with completed family could be feasible. This modeling analysis evaluated the clinical and economic potential of OS at gynecologic and abdominal surgeries. A state transition model representing all relevant health states (healthy, healthy with hysterectomy or tubal ligation, healthy with other gynecologic or non-gynecologic abdominal surgery, healthy with hysterectomy and salpingectomy, healthy with salpingectomy, healthy with hysterectomy and salpingo-oophorectomy, ovarian cancer and death) was developed and informed with transition probabilities based on inpatient case numbers in Germany (2019). Outcomes for women aged 20-85 years were simulated over annual cycles with 1,200,000 million individuals. We compared four strategies: (I) OS at any suitable abdominal surgery, (II) OS only at any suitable gynecologic surgery, (III) OS only at hysterectomy or sterilization, and (IV) no implementation of OS. Primary outcome measures were prevented ovarian cancer cases and deaths as well as the incremental cost-effectiveness ratio (ICER). Volume of eligible interventions in strategy I was 3.5 times greater than in strategy III (286,736 versus 82,319). With strategy IV as reference, ovarian cancer cases were reduced by 15.34% in strategy I, 9.78% in II, and 5.48% in III. Setting costs for OS to €216.19 (calculated from average OS duration and operating room minute costs), implementation of OS would lead to healthcare cost savings as indicated by an ICER of €-8,685.50 per quality-adjusted life year (QALY) gained for strategy I, €-8,270.55/QALY for II, and €-4,511.86/QALY for III. Sensitivity analyses demonstrated stable results over a wide range of input parameters with strategy I being the superior approach in the majority of simulations. However, the extent of cancer risk reduction after OS appeared as the critical factor for effectiveness. Preventable ovarian cancer cases dropped to 4.07% (I versus IV), 1.90% (II versus IV), and 0.37% (III versus IV) if risk reduction would be <27% (hazard ratio [HR] > 0.73). ICER of strategies I and II was lower than the 2× gross domestic product per capita (GDP/C) (€94,366/QALY, Germany 2022) within the range of all tested parameters, but strategy III exceeded this threshold in case-risk reduction was <35% (HR > 0.65). The study is limited to data from the inpatient sector and direct medical costs. Based on our model, interdisciplinary implementation of OS in any suitable abdominal surgeries could contribute to prevention of ovarian cancer and reduction of healthcare costs. The broader implementation approach demonstrated substantially better clinical and economic effectiveness and higher robustness with parameter variation. Based on a lifetime cost saving of €20.89 per capita if OS was performed at any suitable abdominal surgery, the estimated total healthcare cost savings in Germany could be more than €10 million annually.

This study evaluated factors that influence the cost-effectiveness of talazoparib, particularly for patients with a germline breast-cancer-gene-(brca)-mutation and locally advanced or metastasized breast cancer within the context of the German healthcare system. We constructed a partitioned survival model to compare medical costs and treatment effectiveness for patients with such cancers over 45 months. Transition probabilities were derived from survival data from a randomized Phase-III EMBRACA trial, utilities based on published reports, and costs in Euros, which included costs for drug acquisition, clinical monitoring, and treatment of adverse events. Willingness-to-pay thresholds were set to be multiples of the current German per capita gross domestic product. Treatment with talazoparib led to a gain of 0.32 life-years (0.22 quality-adjusted life-years). The mean total cost of €84,003 for talazoparib and €12,741 for standard therapy resulted in an incremental cost-effectiveness ratio of €223,246 per life-year and €323,932 per quality-adjusted life-year gained, indicating that talazoparib is unlikely to be cost-effective at current pricing.