Frozen and Invariant Quantum Discord under Local Dephasing Noise

In this chapter, we intend to explore and review some remarkable dynamical properties of quantum discord under various different open quantum system models. Specifically, our discussion will include several concepts connected to the phenomena of time invariant and frozen quantum discord. Furthermore, we will elaborate on the relation of these two phenomena to the non-Markovian features of the open system dynamics and to the usage of dynamical decoupling protocols.Comment: 29 pages, 8 figure

Accessible quantification of multiparticle entanglement

Entanglement is a key ingredient for quantum technologies and a fundamental signature of quantumness in a broad range of phenomena encompassing many-body physics, thermodynamics, cosmology and life sciences. For arbitrary multiparticle systems, entanglement quantification typically involves nontrivial optimisation problems, and it may require demanding tomographical techniques. Here, we develop an experimentally feasible approach to the evaluation of geometric measures of multiparticle entanglement. Our framework provides analytical results for particular classes of mixed states of N qubits, and computable lower bounds to global, partial, or genuine multiparticle entanglement of any general state. For global and partial entanglement, useful bounds are obtained with minimum effort, requiring local measurements in just three settings for any N. For genuine entanglement, a number of measurements scaling linearly with N are required. We demonstrate the power of our approach to estimate and quantify different types of multiparticle entanglement in a variety of N-qubit states useful for uantum information processing and recently engineered in laboratories with quantum optics and trapped ion setups

Deficient nitric oxide signalling impairs skeletal muscle growth and performance : involvement of mitochondrial dysregulation

Background: Nitric oxide (NO), generated in skeletal muscle mostly by the neuronal NO synthases (nNOS mu), has profound effects on both mitochondrial bioenergetics and muscle development and function. The importance of NO for muscle repair emerges from the observation that nNOS signalling is defective in many genetically diverse skeletal muscle diseases in which muscle repair is dysregulated. How the effects of NO/nNOS mu on mitochondria impact on muscle function, however, has not been investigated yet. Methods: In this study we have examined the relationship between the NO system, mitochondrial structure/activity and skeletal muscle phenotype/growth/functions using a mouse model in which nNOS mu is absent. Also, NO-induced effects and the NO pathway were dissected in myogenic precursor cells. Results: We show that nNOS mu deficiency in mouse skeletal muscle leads to altered mitochondrial bioenergetics and network remodelling, and increased mitochondrial unfolded protein response (UPRmt) and autophagy. The absence of nNOS mu is also accompanied by an altered mitochondrial homeostasis in myogenic precursor cells with a decrease in the number of myonuclei per fibre and impaired muscle development at early stages of perinatal growth. No alterations were observed, however, in the overall resting muscle structure, apart from a reduced specific muscle mass and cross sectional areas of the myofibres. Investigating the molecular mechanisms we found that nNOS mu deficiency was associated with an inhibition of the Akt-mammalian target of rapamycin pathway. Concomitantly, the Akt-FoxO3-mitochondrial E3 ubiquitin protein ligase 1 (Mul-1) axis was also dysregulated. In particular, inhibition of nNOS/NO/cyclic guanosine monophosphate (cGMP)/cGMP-dependent-protein kinases induced the transcriptional activity of FoxO3 and increased Mul-1 expression. nNOS mu deficiency was also accompanied by functional changes in muscle with reduced muscle force, decreased resistance to fatigue and increased degeneration/damage post-exercise. Conclusions: Our results indicate that nNOS mu/NO is required to regulate key homeostatic mechanisms in skeletal muscle, namely mitochondrial bioenergetics and network remodelling, UPRmt and autophagy. These events are likely associated with nNOS mu-dependent impairments of muscle fibre growth resulting in a deficit of muscle performance

Italian survey on the clinical management of non-small cell lung cancer patients during the COVID-19 pandemic: A lesson for the second wave

This study investigated the clinical management of non small cell lung cancer (NSCLC) patients during the first wave of coronavirus disease 2019 (COVID-19) outbreak in Italy. A 29-questions survey was sent to 95 Italian thoracic oncologists, with 77 % of them declaring significant changes in the outpatients management and treatment. The results of this survey pointed out a significant delay of lung cancer diagnosis along with a relevant reduction of patients’ accrual within clinical trials. Telemedicine emerged as a valid support for patient-healthcare interactions. Therapeutic indications followed the guidelines for adjuvant chemotherapy and concurrent chemo-radiation. Clinical indications to first-line therapies were largely confirmed, while major changes regarded the selection of second line treatment options as well as the management of elderly population. This work may represent a valid source of information to improve the clinical management of NSCLC patients during second wave of COVID-19 pandemic

A cross-sectional study evaluating the exercise discussion with oncologist during cancer consultation: the CONNECT study

Background: Evidence demonstrates that physical exercise confers several psycho-physical benefits on patients with cancer. This study aims to investigate the role of oncologists in exercise promotion. Patients and methods: A multicenter, cross-sectional study was conducted by distributing an anonymous, self-administered questionnaire to patients with cancer. The questionnaire enclosed demographic, health, and exercise variables. The exercise-related questions included in the study used the Godin-Shephard Leisure-Time Physical Activity Questionnaire to measure the amount of physical exercise. In addition, the survey gathered information on whether exercise was discussed with patients, and whether oncologists followed the assess, advise, reinforce, and refer (AARR) process regarding exercise. The survey also asked if patients preferred that exercise be discussed during their consultations. Descriptive statistics and logistic regression were applied. Results: With a response rate of 75%, a total of 549 patients completed the survey. Regarding the exercise discussion, 38% of patients stated that their oncologist initiated an exercise discussion, 14% started the discussion themselves, and 48% said that the issue was not considered. Overall, 35% of patients reported that the oncologist assessed their exercise level, 22% and 42% received advice or reinforcement to increase their exercise, respectively, and 10% were referred to a dedicated service. Regarding preferences, 72% of patients thought that the oncologists should initiate an exercise discussion, 2% that only patients should start the discussion, and 26% thought that the issue should not be discussed. Similarly, 74% of patients are willing to receive the exercise assessment, 59% and 75% the advice and reinforcement to increase their exercise, and 46% to be referred to an exercise service. Conclusions: Although exercise promotion rates are low, patients are willing to receive exercise information. Dedicated strategies should be developed to support oncologists in promoting exercise to their patients