Exergy of passive states: Waste energy after ergotropy extraction.

Work extraction protocol is always a significant issue in the context of quantum batteries, in which the notion of ergotropy is used to quantify a particular amount of energy that can be extracted through unitary processes. Given the total amount of energy stored in a quantum system, quantifying wasted energy after the ergotropy extraction is a question to be considered when undesired coupling with thermal reservoirs is taken into account. In this paper, we show that some amount of energy can be lost when we extract ergotropy from a quantum system and quantified by the exergy of passive states. Through a particular example, one shows that ergotropy extraction can be done by preserving the quantum correlations of a quantum system. Our study opens the perspective for new advances in open system quantum batteries able to explore exergy stored as quantum correlations.

Entanglement, coherence, and charging process of quantum batteries.

Quantum devices are systems that can explore quantum phenomena, such as entanglement or coherence, for example, to provide some enhancement performance concerning their classical counterparts. In particular, quantum batteries are devices that use entanglement as the main element in their high performance in powerful charging. In this paper, we explore quantum battery performance and its relationship with the amount of entanglement that arises during the charging process. By using a general approach to a two- and three-cell battery, our results suggest that entanglement is not the main resource in quantum batteries, where there is a nontrivial correlation-coherence tradeoff as a resource for the high efficiency of such quantum devices.

Effects of intrathecal triamincinolone-acetonide treatment in MS patients with therapy-resistant spasticity.

OBJECTIVES: Multiple sclerosis (MS) is an autoimmune disease affecting young people and is a major cause of disability. In the course of time, disability progresses and symptoms like spasticity may occur. Spasticity is a major cost factor in MS patients. Various agents are approved for the treatment of spasticity, but each of those agents may have several side effects. Intrathecally administered steroids (triamcinolone-acetonide (TCA)) may be efficient in treating spasticity in patients with lesions in the spinal cord and no response to first-line therapeutics. The aim of this study is to show effects of TCA treatment on clinical parameters in patients with MS. METHODS: This multicentre open label study included 54 patients with MS. The clinical outcome parameters were spasticity, disability, maximum walking distance, bladder function and quality of life. All patients received physiotherapy in addition to TCA treatment to obtain optimal effects on clinical parameters. RESULTS: Spasticity, maximum walking distance as well as disability improved significantly (P ⩽ 0.001) during TCA applications. Bladder function improved in every seventh patient. CONCLUSION: We observed the effects of intrathecally administered TCA on different clinical parameters including bladder function. TCA administration is a safe method to treat different symptoms in MS patients. Longitudinal trials with repeated TCA cycles are needed to show long-term effects. Besides TCA treatment, physiotherapy contributes to the improvement of clinical parameters.

Effects of repeated intrathecal triamcinolone-acetonide application on cerebrospinal fluid biomarkers of axonal damage and glial activity in multiple sclerosis patients.

BACKGROUND AND OBJECTIVES: Multiple sclerosis (MS) is the most common inflammatory disease of the central nervous system in young adults. Over time, the disease progresses and, with accumulating disability, symptoms such as spasticity may occur. Although several treatment options are available, some patients may not respond to first-line therapeutics. However, some of these patients may benefit from intrathecally administered triamcinolone-acetonide (TCA), a derivative of glucocorticosteroids (GCS). GCS may have neurotoxic effects, and cell apoptosis may occur. The aim of this study was to investigate the effects of TCA on biomarkers in the cerebrospinal fluid (CSF) suggestive of neurodegeneration. METHODS: In order to assess neurotoxic effects of TCA, neurofilament heavy-chain (NfH)(SMI35), tau protein, and S-100B protein levels were determined before and during treatment with TCA in 54 patients with primary progressive MS, as well as relapsing MS (relapsing-remitting and secondary progressive MS). RESULTS: NfH(SMI35) levels in the CSF of patients treated with TCA intrathecally did not increase significantly during the treatment cycle (p = 0.068). After application of TCA, tau protein levels were increased significantly at day 4 (p = 0.03) and at day 8 (p ≤ 0.001). S-100B protein levels decreased significantly (p ≤ 0.05) during treatment with TCA. CONCLUSION: NfH(SMI35) levels did not change significantly; however, tau protein levels did increase significantly within the reference range. Taking these findings together, the long-term effects of TCA on NfH(SMI35) and tau protein levels need to be investigated further to understand whether levels of both biomarkers will change over repeated TCA applications. Interestingly, S-100B protein levels decreased significantly during the first applications, which may have represented reduced astrocytic activity during TCA treatment.